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  • 1965-1969  (7,841)
  • 1890-1899  (2,322)
  • General Chemistry  (8,626)
  • Chemical Engineering  (1,448)
  • Cat  (55)
  • Insulin  (35)
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  • 1
    Electronic Resource
    Electronic Resource
    Über Wirkungen von N-Amidino-3,5-diamino-6-chloro-pyrazin-carboxamid (Amilorid) auf den Glucosetransport und den Leucineinbau in Proteine des epididymalen Fettgewebes der Ratte (1969)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 262 (1969), S. 139-151 
    Details
    ISSN: 1432-1912
    Keywords: Amiloride ; Insulin ; Glucose Transport ; Leucine Incorporation ; Isolated Adipose Tissue ; Amilorid ; Insulin ; Glucosetransport ; Leucineinbau ; isoliertes Fettgewebe
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 1. Die Aufnahme von Glucose ins isolierte epididymale Fettgewebe und die Bildung von 14CO2 aus [1-14C]-Glucose wurde als Maß von Transportvorgängen, die Incorporation von [1-14C]-Leucin ins Fettgewebsprotein als Maß der Proteinsynthese vor und nach Zusatz von Amilorid in vitro verwendet. 2. Amilorid setzt den Transport durch die Membran sowohl ohne als auch mit Stimulierung durch Insulin halbmaximal in 10−4 M-Konzentration herab. Aus der Kinetik des Transportes kann geschlossen werden, daß Amilorid die maximale Geschwindigkeit des gesamten Vorganges verlangsamt, ohne die Transportkonstante zu verändern. 3. Der Einbau von Leucin ins Fettgewebsprotein wird durch Amilorid in 3 · 10−4 M-Konzentration auf ein Zehntel herabgesetzt. Das Verhalten von [1-14C]-α-Aminoisobuttersäure läßt den Schluß zu, daß der Aminosäuretransport durch die Membran des Fettgewebes nicht beeinflußt wird. 4. Die Wirkungen des Amilorids am Fettgewebe entsprechen im Prinzip denjenigen des Triamterens und des 6-Aminonicotinsäureamids. Ebenso ist allen gemeinsam, daß sie den renalen Natrium- und Kaliumtransport im distalen Abschnitt des Nephrons hemmen. 5. Es ist möglich, daß ein Zusammenhang zwischen den hemmenden Wirkungen dieser Pharmaka auf den Leucin-Einbau in das Fettgewebsprotein und der Störung von Transportvorgängen durch biologische Membranen besteht.
    Notes: Summary 1. The uptake of glucose and the formation of 14CO2 from [1-14C]-glucose were used as a measure of transport processes, and the incorporation of [1-14C]-leucine into the protein of adipose tissue served as a measure of protein synthesis before and after the addition of amiloride to the isolated epididymal adipose tissue of the rat in vitro. 2. In a concentration of 10−4 M, amiloride decreases the glucose transport through tissue membranes by 50% with and without stimulation by insulin. It can be deduced from the kinetics of the transport that amiloride slows down the maximal velocity of the complete process without influencing the transport constant. 3. The incorporation of leucine into adipose tissue protein was diminished to 10% by amiloride in a concentration of 3 × 10−4 M. Experiments with [1-14C]-α-aminoisobutyric acid allow the conclusion that the amino acid transport through the membrane of the adipose tissue remains uninfluenced. 4. The effects of amiloride on the adipose tissue are similar to those of triamterene and of 6-aminonicotinamide. In addition, they all inhibit renal sodium and potassium transport in the distal part of the nephron. 5. It is possible, that there is a connection between the inhibiting effects of these drugs on the incorporation of leucine into the protein of adipose tissue and the disturbance of transport processes through biological membranes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00537655
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  • 2
    Electronic Resource
    Electronic Resource
    Die Bestimmung der intestinalen Resorption von Herzglykosiden durch Messung der3H-markierten Glykoside im Portalvenenblut und in der Darmlymphe bei Katzen (1969)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 264 (1969), S. 406-419 
    Details
    ISSN: 1432-1912
    Keywords: Intestinal Absorption ; Cardiac Glycosides ; Blood of Portal Vein ; Intestinal Lymph ; Cat ; Intestinale Resorption ; Herzglykoside ; Portalvenenblut ; Darmlymphe ; Katze
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. The cardiac glyoosides digitoxin, ouabain, digoxin and peruvosid labelled with3H were injected into tied intestinal loops of anaesthetized cats in situ. The absorbed glycosides were measured in the blood of the portal vein and in the intestinal lymph. At the same time the3H-activity was measured in the blood of the peripheral circulation, in the bile and in the urine. 2. Calculation of the amount of glycosides totally absorbed from the3H-concentration in the blood of the portal vein and the circulation volume (bubble-flow-meter) gave the following absorption rates as a percentage of the administered dose per hour: digitoxin 56%, digoxin 42%, peruvosid 26% and ouabain 10%. 3. The amount of glycosides passing into the lymph during 1 hour was found to be only 0.006 to 0.02% of the amount offered. In lymph3H-activity cannot be measured earlier than 5 min after the administration of the labelled glycosides. The3H-concentration in the lymph did not equal that measured in the blood of the peripheral circulation until at least 1 hour after the administration and always remained below the3H-concentration of the blood in the portal vein. This proportion remained unchanged even if digitoxin was administered as an emulsion in oil instead of an aqueous solution. From the time course of3H-concentration it might be concluded that the glycosides do not pass directly to the lymph after absorption but indirectly by way of the blood. 4. The amount of glycoside excreted in the bile is for peruvosid 15,5% of the amount absorbed, for ouabain 1,9%, for digoxin 1,4% and for digitoxin 0,8%. The3H-activity excreted in urine is very small and can be disregarded. 5. Chromatographic analyses of the bile revealed, that in the case of digoxin, 4/5 of the amount excreted were unchanged, in the case of digitoxin and ouabain 2/3 and in the case of peruvosid only 1/4. In the lumen of the tied intestinal loops and in the tissue of the small intestine the glycosides were hardly metabolised.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01002379
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  • 3
    Electronic Resource
    Electronic Resource
    Über die Gefäßversorgung des Corpus callosum der Katze (1969)
    Springer
    Anatomy and embryology 128 (1969), S. 28-39 
    Details
    ISSN: 1432-0568
    Keywords: Arterial supply ; Corpus callosum ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung An 27 Katzen beiderlei Geschlechts wurde die Blutversorgung des Corpus callosum untersucht. Dabei wurden folgende Befunde erhoben: Der Balken der Katze wird im Bereich des Rostrum und Genu sowie im vorderen und mittleren Truncuabschnitt aus der Arteria cerebri anterior versorgt und zwar über Äste, die den Arteriae pericallosae und den Arteriae genu corporis callosi entstammen. Diese Äste wurden als Arteriae callosi superiores und inferiores bezeichnet. Lediglich im hinteren Truncusabschnitt und im Splenium erfolgt die Versorgung neben Ästen der A. pericall. auch über solche der Arteriae cerebri mediae und posteriores. Die Blutgefäße treten dolchartig in den Balken ein, teilen sich dann baumartig weiter auf und gehen in ein Capillarnetz über, das in Richtung des Nervenfaserverlaufes ausgezogen ist. Auf in der Literatur bereits bekannte, aber oft vernachlässigte Besonderheiten der Arteria carotis interna und des Circulus arteriosus wird hingewiesen.
    Notes: Summary In investigations on 27 cats of both sexes, the arterial supply of the corpus callosum was studied. The findings are as follows: In the region comprising rostrum and genu as well as in the fore and middle trunk sections, blood supplied by branches of the arteriae pericallosae and the arteriae genu corporis callosi which originate from the arteria cerebri anterior. These branches were designated arteriae callosi superiores and inferiores. However, in the posterior section of the trunk and in the splenium the blood is supplied by branches of the aa. pericall. and, in addition, by branches of the arteriae cerebri media and posteriores. The blood vessels penetrate the corpus callosum in bayonet fashion, then arborise and finally become a capillary network which is elongated in the direction of the course of the nerve fibres. Attention is drawn to peculiarities of the arteria carotis interna and the circle of Willis which, although known in the literature, are rarely referred to.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00522492
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  • 4
    Electronic Resource
    Electronic Resource
    Quantitative Untersuchungen an Gliazellen im Corpus callosum wachsender Katzen nach Perfusions- und Immersionsfixierung (1969)
    Springer
    Anatomy and embryology 128 (1969), S. 222-234 
    Details
    ISSN: 1432-0568
    Keywords: Postnatal development ; Fixation ; Neuroglia ; Corpus callosum ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Gehirne von Tieren aus 4 verschieden alten Würfen junger Katzen wurden teils lebensfrisch durch Perfusion, teils nach 24 Std durch Immersion fixiert und für Vergleichsuntersuchungen in Paraffin eingebettet. Bei Betrachtung der Gliazellen des Corpus callosum ergab sich: 1. Nach Perfusionsfixierung sind die Kerne der Gliazellen groß und elliptisch. Sie sind wasserklar und haben eine scharf gezeichnete Chromatinstruktur. Nach Immersionsfixierung 24 Std p.m. sind die Kerne dagegen klein und rund, homogen dunkel gefärbt und haben ein kaum zu erkennendes Chromatingerüst. 2. Nach Perfusionsfixierung sieht man im Balken der ganz jungen Tiere zahlreiche Mitosen. Sie fehlen bei den durch Immersion fixierten Geschwistertieren desselben Wurfes. 3. Die nach verschiedener Fixierung beobachteten Unterschiede in der Form der Gliazellkerne werden durch Messungen der Quer- und Längsachsen erfaßt.
    Notes: Summary In four litters of young cats, some of the brains were fixed by perfusion and the others by immersion. The material was embedded in paraffin and the neuroglia was investigated in sections through the corpus callosum. It was found that: 1. After fixation by perfusion the nuclei of the glia cells are large and elliptic. The caryoplasm is clear and there is a distinct structure of the chromatin. After fixation by immersion the nuclei of the same cells are small and round. The caryoplasm is dense and the structure of the chromatin is not clearly visible. 2. After fixation by perfusion mitotic figures are present. They are absent in the brains fixed by immersion. 3. Following different fixation, there are differences in the shape of the nuclei of the glial cells. These differences have been investigated in detail by measuring the diameters of the nuclei.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00521281
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  • 5
    Electronic Resource
    Electronic Resource
    Effect of insulin on glucagon enhanced lipolysis in vitro (1969)
    Springer
    Diabetologia 5 (1969), S. 195-197 
    Details
    ISSN: 1432-0428
    Keywords: Insulin ; glucagon ; adipose tissue ; lipolysis ; FFA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé A des concentrations proches de celles qui sont rencontrées dans le plasma humain, le glucagon stimule fortement la lipolyse au niveau de la graisse épididymaire du rat, étudiéein vitro. Les effets de telles concentrations de glucagon sont réduits, voire abolis par l'insuline aux concentrations de 25 et 100μU/ml. Rapprochées de l'effet insulinogénique puissant du glucagon, ces observations peuvent fournir une explication quant au caractère retardé de l'élévation du taux sanguin des acides gras libres observée après injection de glucagonin vivo.
    Abstract: Zusammenfassung Glucagon stimuliert in Konzentrationen, wie sie auch im menschlichen Plasma vorkommen, die Lipolyse im Ratten-Nebenhodenfettgewebein vitro stark. Die Effekte derartiger Glucagonkonzentrationen werden durch Insulin (25–100μE/ml) verringert bis aufgehoben. Unter Berücksichtigung der ausgeprägten Wirkung von Glucagon auf die Insulinfreisetzung können diese Beobachtungen eine Erklärung für die Verzögerung des Anstiegs der freien Fettsäuren im Serum liefern, die man nach Glucagoninjektionenin vivo beobachtet.
    Notes: Summary Glucagon in concentrations similar to those found in human plasma markedly stimulates lipolysis in rat adipose tissuein vitro. The effects of these “physiological” concentrations of glucagon are reduced or abolished by insulin at concentrations of 25 and 100μU/ml. Considering the marked insulinogenic effect of glucagon these observations may provide an explanation for the delayed increase of blood FFA observed after glucagon injectionin vivo.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01213680
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  • 6
    Electronic Resource
    Electronic Resource
    Insulin release by isolated pancreatic islets of the mouse incubated in vitro (1969)
    Springer
    Diabetologia 5 (1969), S. 61-66 
    Details
    ISSN: 1432-0428
    Keywords: Insulin ; islets of Langerhans ; mouse ; collagenase ; glucose ; mannoheptulose ; glucagon ; adrenaline ; phentolamine ; theophylline ; tolbutamide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé La libération de l'insuline pendant l'incubation des îlots de Langerhans de la souris, isolés après digestion du pancréas par la collagénase, a été étudiée, et l'influence de divers facteurs sur la vitesse de libération a été recherchée. Le glucose à 3.0 mg/ml (glucose élevé) stimulait la libération d'insuline, mais n'avait pas d'effet à 0.6 mg/ml (taux bas). Le mannoheptulose bloquait la stimulation provoquée par du glucose élevé, comme le faisait l'adrénaline. L'effet de l'adrénaline était aboli par la phentolamine, un agent bloquant alpha adrénergique. Le glucagon seul, ainsi qu'en pre'sence d'un taux de glucose bas, stimulait la libération d'insuline, mais non de façon constante avec un taux de glucose élevé. L'adrénaline abolissait la stimulation provoquée par le glucagon. La théophylline stimulait la libération lorsque le glucose était bas, mais beaucoup moins lorsque le glucose était élevé et pas du tout avec le glucagon, quelle que soit la concentration de glucose. Le tolbutamide stimulait la libération d'insuline avec une faible concentration de glucose et cet effet n'était pas inhibé par l'adrénaline. La convenance de cette préparation pour des études sur le métabolisme des cellules insulaires et sa relation avec la sécrét ion d'insuline est discutée.
    Abstract: Zusammenfassung Es wurde die Insulinausschüttung aus Langerhans'schen Inseln von Mäusen, die durch Kollagenase-Behandlung des Pankreas gewonnen worden waren, untersucht und der Einfluß verschiedener Faktoren auf die Freisetzungsgeschwindigkeit überprüft. Eine hohe Glucose-Konzentration von 3.0 mg/ml förderte die Insulin-Ausschüttung, während die niedrige Konzentration von 0.6 mg/ml keine Wirkung ergab. Mannoheptulose und Adrenalin blockierten die Stimulation durch die hohe Glucosekonzentration. Der AdrenalinEffekt konnte durch Phentolamin, eine alpha-Rezeptoren blockierende Substanz, wieder aufgehoben werden. Glucagon führte allein und in Gegenwart der niedrigen Glucosekonzentration zu einer verstärkten Insulininkretion: dies war jedoch bei Kombination mit der hohen Glucosekonzentration nicht konstant der Fall. Adrenalin hob die Stimulierung durch Glucagon auf. Theophyllin führte bei Gegenwart der niedrigen Glucosekonzentration zu einer gesteigerten Ausschüttung, dieser Effekt trat unter der höheren Glucosekonzentration in wesentlich geringerem Umfang und bei Zusatz von Glucagon und einer der beiden verwandten Glucosekonzentrationen überhaupt nicht auf. Bei niedriger Glucosekonzentration stimulierte Tolbutamid die Insulinfreisetzung; dieser Effekt ließ sich durch Adrenalin nicht aufheben. Die Aussagefähigkeit dieses Präparates für Untersuchungen des Inselzell-Stoffwechsels und seiner Beziehungen zur Insulininkretion wird diskutiert.
    Notes: Summary The release of insulin during incubation of mouse islets of Langerhans, isolated after digestion of the pancreas with collagenase, has been studied, and the influence of various factors on the rate of release investigated. Glucose at 3.0 mg/ml (high glucose) stimulated insulin release, but had no effect at 0.6 mg/ml (low glucose). Mannoheptulose blocked the stimulation by high glucose, as did adrenaline. The adrenaline effect was abolished by phentolamine, an alpha-adrenergic blocking agent. Glucagon alone, stimulated insulin release, and also with low glucose, but not consistently with high glucose. Adrenaline abolished the stimulation by glucagon. Theophylline stimulated release with low glucose, much less so with high glucose and not at all with glucagon at either glucose concentration. Tolbutamide stimulated release with low glucose, and this effect was not inhibited by adrenaline. The suitability of this preparation for studies of islet cell metabolism and its relationship to secretion of insulin is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01211999
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  • 7
    Electronic Resource
    Electronic Resource
    Insulin in bile (1969)
    Springer
    Diabetologia 5 (1969), S. 304-308 
    Details
    ISSN: 1432-0428
    Keywords: Insulin ; bile ; rabbit ; 125I-insulin ; glucose ; galactose ; fructose ; tolbutamide ; phenformin ; liver
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé On trouve de l'insuline immunoréactive dans la bile hépatique de lapins normaux. Moins de 1% d'une dose injectée d'insuline bovine atteint la bile. Quand de l'insuline bovine 125I, seule ou liée à l'anticorps, est administrée par voie intraveineuse, seulement 40% de la radioactivité retrouvée dans la bile est précipitable avec l'acide trichloracétique et moins de 10% réagit avec le sérum anti-insuline de cobaye. Le glucose, le fructose le galactose, le tolbutamide et la phenformine provoquent tous une élévation de l'insuline dans la bile, qui atteint son maximum 40 à 50 min après l'injection. L'alloxane atténue ou abolie ces réponses.
    Abstract: Zusammenfassung Immunoreaktives Insulin wird in der Leber-Galle normaler Kaninchen gefunden. Weniger als 1% einer injizierten Dosis von Rinder-Insulin erreicht die Galle. Wenn man reines oder an Antikörper gebundenes 125I-Rinderinsulin intravenös verabreicht, lassen sich mit Hilfe von Trichloressigsäure nur 40% der Radioaktivität ausfällen, die in der Galle gefunden wird, und weniger als 10% reagieren mit Meerschweinchen-Anti-Insulinserum. Glucose, Fructose, Galaktose, Tolbutamide und Phenformin verursachen ein Ansteigen von Insulin in der Galle, welches ein Maximum innerhalb von 40 bis 50 Min. nach der Injektion erreicht. Alloxan vermindert oder hebt diese Effekte auf.
    Notes: Summary Immuno-reactive insulin is found in the hepatic bile of normal rabbits. Less than 1% of an injected dose of bovine insulin reached the bile. When 125I-bovine insulin alone or complexed with antibody was given intravenously, only 40% of the radioactivity recovered in the bile was precipitable with trichloracetic acid, and less than 10% reacted with guinea pig anti-insulin serum. Glucose, fructose, galactose, tolbutamide and phenformin all caused an elevation in bile insulin, which reached a maximum 40 to 50 min after the injection. Alloxan attenuated or abolished these responses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00452903
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  • 8
    Electronic Resource
    Electronic Resource
    Experimentelle Untersuchungen über die blutzuckersenkende Wirkung von Rinder-Proinsulin (1969)
    Springer
    Diabetologia 5 (1969), S. 325-330 
    Details
    ISSN: 1432-0428
    Keywords: Insulin ; proinsulin ; blood sugar ; mice ; rats ; pancreatectomy ; nephrectomy ; hepatectomy (partial) alloxan diabetes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Chez les rats et les souris le taux du sucre sanguin est abaissé par une proinsuline obtenue à partir de l'insuline bovine (Schmidt et Arens [6]). Chez les rats alimentés et les souris à jeun, le rapport d'activité proinsuline: insuline est de 1∶4, chez les rats à jeun de 1∶2, dans le cas de dose équimolaire et en mesurant l'abaissement maximum du sucre sanguin. L'abaissement du sucre sanguin évolue de façon plus lente après proinsuline qu'après insuline. La proinsuline, incubée in vitro avec la trypsine, agit quantitativement et au point de vue temps, comme l'insuline. Chez les rats pancréatectomisés, chez les rats néphrectomisés ainsi que chez ceux hépatectomisés aux deux tiers, l'action de la proinsuline est la même que chez les animaux normaux. Les souris rendues diabétiques par l'alloxane répondent également à la proinsuline comme les souris intactes. L'action hypoglycémiante de la proinsuline se manifeste de façon retardée probablement parce que l'insuline active doit tout d'abord se former par un processus protéolytique dépendant du facteur temps. Ceci pourrait être aussi la raison pour laquelle, Rubenstein et coll. [5] signalent l'absence d'effet de la proinsuline dans le test de convulsion chez la souris.
    Abstract: Zusammenfassung An Ratten und Mäusen wird der Blutzucker durch ein aus Rinderinsulin gewonnenes Proinsulin (Schmidt und Arens [6]) gesenkt. Bei gefütterten Ratten und nüchternen Mäusen ist das WirkungsVerhältnis Proinsulin: Insulin = 1∶4, bei nüchternen Ratten 1∶2, wenn äquiznolar dosiert und das Maximum der Blutzuckersenkung gewertet wird. Die Blutzuckersenkung verläuft nach Proinsulin protrahierter als nach Insulin. Proinsulin, welches in vitro mit Trypsin inkubiert wurde, wirkt quantitativ und zeitlich wie Insulin. Bei pankreatektomierten, bei nephrektomierten und bei zweidrittelhepatektomierten Ratten wirkt Proinsulin ebenso wie an Normaltieren. Auch alloxandidbetische Mäuse sprechen auf Proinsulin wie intakte Mäuse an. Die hypoglykämische Wirkung des Proinsulins tritt wahrscheinlich deshalb verzögert ein, weil das aktive Insulin in einem zeitabhängigen proteolytischen Prozeß erst entstehen muß. Dies könnte auch die Ursache für eine von Rubenstein et al. [5] zitierte, fehlende Wirkung von Proinsulin im Mäusekrampftest sein.
    Notes: Summary Proinsulin obtained from bovine insulin (Schmidt and Arens [6]) lowered the blood sugar level of rats and mice. The activity ratio proinsulin: insulin was 1∶4 in fed rats and fasted mice, and 1∶2 in fasted rats, based on an equimolar dosage and measuring the effect in terms of maximum lowering of the blood sugar value. After proinsulin the decrease of the blood sugar was more protracted than after insulin. Proinsulin which was incubated with trypsin in vitro, resembled insulin in degree and onset of action. In pancreatectomized, nephrectomized and two-thirds hepatectomized rats proinsulin acted as in normal animals. Alloxan-diabetic mice responded to proinsulin like intact mice. The reason why the onset of the hypoglycaemic action of proinsulin was delayed is probably due to the fact that the active insulin must first be produced by a time-dependent proteolytic process. This may also be the cause of the ineffectiveness of proinsulin in the mouse convulsion test which was quoted by Rubenstein et al. [5].
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00452907
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  • 9
    Electronic Resource
    Electronic Resource
    Localization of insulin in mouse tissues using fluorescence microscopy and light microscope and high resolution autoradiography. (1969)
    Springer
    Diabetologia 5 (1969), S. 67-78 
    Details
    ISSN: 1432-0428
    Keywords: Insulin ; mouse tissues ; kidney fluorescence microscopy ; microscopy ; autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé La localisation d'insuline marquée avec I125 ou avec de l'isothiocyanate de fluorescéine a été étudiée au moyen d'autohistoradiographie au microscope optique, au microscope électronique et au moyen de microscopie à fluorescence dans les tissus de souris à jeun et de souris alimentées normalement. L'hormone fluorescente a été trouvée dans les cellules des tubules proximaux du rein de souris à jeun seulement, tandis que l'hormone radioactive a été repérée aussi dans le rein de souris alimentées, bien qu'en quantité inférieure à celle trouvée chez les souris à jeun. Au microscope électronique la radioactivité est présente dans le rein dans la bordure en brosse, les vacuoles et les mitochondries apicales et le noyau, mais pas dans l'appareil de Golgi ou dans les lysosomes. —L'hormone radioactive est aussi présente dans les autres tissus mais sans différence quantitative entre les souris à jeun et les souris alimentées. Les auteurs concluent que le procédé de ré-absorption de l'insuline par les cellules des tubules proximaux du rein est spécifique: l'hormone n'est pas dégradée de la même façon que les autres protéines mais probablement stockée afin de contrôler les processus métaboliques relevant des organelles subcellulaires dans lesquelles elle se trouve.
    Abstract: Zusammenfassung Gefütterte und fastende Mäuse erhielten fluoreszierendes oder mit125J markiertes Insulin i.v. Die Lokalisation des Insulins in den Geweben wurde untersucht. Nur bei Tieren im Hungerzustand fand sich das fluoreszierende Hormon in den Nieren, während sich das radioaktive Insulin bei gefütterten und fastenden Tieren in den proximalen Tubulusschlingen der Nieren nachweisen ließ. Die fastenden Tiere schienen dabei mehr Radioaktivität aufzuweisen. Wurden die Nieren unter Verwendung von Techniken mit hohem Auflösungsvermögen untersucht, so fand sich die Radioaktivität im Bürstensaum, in den apikalen Vakuolen und Mitochondrien und dem Kern, jedoch nicht im Golgi-Apparat oder den Lysosomen. Alle anderen Gewebe enthielten Hormon-Radioaktivität, aber weder ihre Menge noch ihre Lokalisation unterschieden sich bei gefütterten und fastenden Tieren. Es wird gefolgert, daß der Prozeß der Insulinabsorption durch die Zellen der proximalen Tubulusschlingen spezifisch ist und daß das Hormon nicht in ähnlicher Weise wie andere Eiweißkörper abgebaut wird. Wahrscheinlich kommt es über eine Speicherung zu einer Steuerung der entsprechenden Stoffwechselprozesse in den subzellulären Organellen, in denen das Hormon sich befindet.
    Notes: Summary Starved and fed mice were injected intravenously with either fluorescent or125I-insulin and the localization of the hormone was investigated in various tissues. The fluorescent hormone was found in the kidney of starved animals only, whereas the radioactive hormone was found in the proximal convoluted tubule cells of the kidney of both fed and fasted animals, although the latter group appeared to contain more radioactivity than the first. With high resolution techniques the radioactivity in the kidney was found in the brush border, the apical vacuoles, the apical mitochondria and the nucleus, and never in the Golgi apparatus or the lysosomes. All other tissues contained radioactivity due to the hormone, but no difference in either the amount or the localization was found between fed an starved animals. It is concluded that the process of absorption of insulin by the cells of the proximal convoluted tubules is specific and that the hormone is not degraded in a way similar to other proteins, but is likely to be stored and to control cellular metabolic processes from its sites of localization.
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    URL: http://dx.doi.org/10.1007/BF01212000
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    Electronic Resource
    The stimulatory effect by insulin on the incorporation of32P radioactive inorganic phosphate into intracellular inorganic phosphate, adenine nucleotides and guanine nucleotides of the intact isolated rat diaphragm (1969)
    Springer
    Diabetologia 5 (1969), S. 79-87 
    Details
    ISSN: 1432-0428
    Keywords: Insulin ; 32P incorporation ; adenine nucleotides ; guanine nucleotides ; Na+K+ ATP-ase ; ouabain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Le but de ces investigations a été de contribuer à la compréhension du mécanisme d'action de l'insuline, en provoquant un turn-over accru du phosphate inorganique marqué au32P, en ATP et autres mononucléotides, dans le diaphragme du rat. Pendant l'incubation du diaphragme intact de rat dans un milieu bicarbonaté de Krebs Ringer, sans addition de substrat, on n'a pas observé d'effet de l'insuline sur le contenu en adénine-nucléotides, en guanine-nucléotides, y compris le 3′5′ AMP cyclique et le 3′5′ GMP cyclique. Quand du phosphate inorganique radioactif marqué au32P était présent dans le milieu, l'insuline augmentait l'activité spécifique du phosphate inorganique intracellulaire et provoquait une incorporation accrue du32P dans l'ATP et le GTP. L'effet sur l'ADP était moins prononcé. Il a été montré que ces effets de l'insuline dépendent de la composition ionique du milieu et du transport membranaire des ions. L'augmentation due à l'insuline de l'activité spécifique du phosphate inorganique intracellulaire et du marquage accru au32P de l'ATP (et du GTP) était en grande partie inhibée par l'ouabaïne. Pendant l'incubation dans les milieux où le chlorure de sodium a été remplacé isoosmotiquement par le chlorure de potassium ou de choline, les effets de l'insuline décrits ci-dessus étaient abolis. Les résultats indiquent que le marquage accru de l'ATP (et du GTP) provoqué par l'insuline, peut être en premier lieu attribué à des phénomènes survenant au niveau de la membrane cellulaire. L'augmentation de l'activité spécifique du phosphate inorganique intracellulaire en présence d'insuline, peut s'expliquer par une captation accrue du phosphate inorganique marqué au32P, à partir du milieu. Apparemment le marquage accru au32P de l'ATP (et du GTP) est une conséquence secondaire. On suggère que cet effet de l'insuline est d'abord en rapport avec un effet sur les enzymes de la membrane, en particulier sur l'ATP-ase activée par Na+, K+ et Mg2+.
    Abstract: Zusammenfassung Ziel dieser Untersuchungen war es, zu einem besseren Verständnis der stimulierenden Wirkung von Insulin auf den Einbau von anorganischem32P Phosphat in ATP und andere Mononucleotide im Rattenzwerchfell beizutragen. Während der Inkubation intakter Rattenzwerchfelle in Krebs-Ringer-Bicarbonat Puffer ohne Substratzusatz konnte kein Insulineffekt auf den Gehalt an Adenonucleotiden und Guaninnucleotiden, sowie von cyclischem 3′,5′ AMP und cyclischem 3′,5′ GMP beobachtet werden. In Gegenwart von anorganischem32P Phosphat steigerte Insulin die spezifische Aktivität von intrazellulärem anorganischen Phosphat und bewirkte einen verstärkten Einbau von32P in ATP und GTP. Die Wirkung auf ADP war weniger ausgeprägt. Es konnte gezeigt werden, daß diese Insulineffekte von dem IonenGehalt des Mediums und dem Membrantransport der Ionen abhängen. Die Steigerung der spezifischen Aktivität des anorganischen Phosphates und der Markierung von ATP (und GTP) mit32P ließ sich weitgehend durch Ouabain wieder aufheben. Bei Inkubation in Pufferlösungen, die statt NaCl isoosmolare Mengen von KCl oder Cholinchlorid enthielten, waren die oben erwähnten Insulineffekte nicht mehr nachweisbar. Die Resultate sprechen dafür, daß die verstärkte Markierung von ATP (und GTP) unter Insulin in erster Linie auf Vorgängen an der Zellmembran beruht. Die erhöhte spezifische Aktivität des intrazellulären anorganischen Phosphates in Gegenwart von Insulin läßt sich durch einen verstärkten Einstrom von32P Phosphat aus dem Medium erklären. Augenscheinlich kommt es dadurch sekundär zu einer gesteigerten32P Markierung von ATP (und GTP). Wir möchten annehmen, daß dieser Insulineffekt vorwiegend über die Membranenzyme erfolgt und sich vor allem auf die Na+, K+ und Mg++ aktivierbare ATPase erstreckt.
    Notes: Summary The aim of these investigations has been to contribute to an understanding of the mechanism of action of insulin in promoting increased turn over of32P inorganic phosphate into ATP and other mononucleotides in the rat diaphragm. During incubation of the intact rat diaphragm in Krebs Ringer bicarbonate medium without addition of substrate, no effect of insulin on the content of adenine nucleotides and guanine nucleotides including cyclic 3′,5′ AMP and cyclic 3′,5′ GMP has been observed. When32P radioactive inorganic phosphate was present in the medium, insulin increased the specific activity of intracellular inorganic phosphate and promoted an increased incorporation of32P into ATP and GTP. The effect on ADP was less pronounced. It has been shown that these effects of insulin depend upon the ionic composition of the medium and on ion membrane-transport. The insulin-promoted increase of specific activity of intracellular inorganic phosphate and of increased32P labelling of ATP (and GTP) was to a great extent inhibited by ouabain. During incubation in media where sodium chloride had been iso-osmotically replaced by potassium chloride or choline chloride, the above mentioned effects by insulin were abolished. The results indicate that the increased labelling of ATP (and GTP) promoted by insulin can be primarily attributed to events occuring at the cell membrane. The increased specific activity of intracellular inorganic phosphate in the presence of insulin can be explained by increased uptake of32P inorganic phosphate from the medium. Apparently the increased32P labelling of ATP (and GTP) occur as a secondary consequence. It is suggested that this insulin effect is primarily concerned with an effect on membrane enzymes, particularly the Na+, K+, Mg2+ activated ATP-ase.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01212001
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    Electronic Resource
    Inability of galactose to mobilize insulin in galactokinase-deficient individuals (1969)
    Springer
    Diabetologia 5 (1969), S. 143-145 
    Details
    ISSN: 1432-0428
    Keywords: Insulin ; galactose ; galactokinase ; deficiency
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Chez deux adultes souffrant d'une déficience en galactokinase la charge orale de galactose a été suivie d'une hypergalactosémie prolongée sans aucune élevation de l'insuline immunoréactive plasmatique.
    Abstract: Zusammenfassung Orale Belastung mit Galactose führte bei zwei Erwachsenen mit Galactokinasemangel zu einer prolongierten Hypergalactosämie, aber nicht zu einem Anstieg des immunoreaktiven Insulins im Plasma.
    Notes: Summary Oral galactose loading in two galactokinase-deficient adults produced the expected high and prolonged rise of galactose in peripheral blood, but no rise of circulating immunoreactive insulin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01213671
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  • 12
    Electronic Resource
    Electronic Resource
    The lateral cervical nucleus in the cat IV. A light and electron microscopical study after midbrain lesions with demonstration of indirect wallerian degeneration at the ultra-structural level (1969)
    Springer
    Experimental brain research 7 (1969), S. 51-67 
    Details
    ISSN: 1432-1106
    Keywords: Lateral cervical nucleus ; Midbrain lesions ; Nauta method ; Ultrastructural investigation ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The lateral cervical nucleus (LCN) has been studied with the light and electron microscope after midbrain lesions in kittens of different ages, and in adult cats. It has been shown that nerve cells remain within the contralateral LCN after hemisection of the midbrain. performed on 1 day old kittens. The estimated number of these remaining cells was 3–19% in the different cases. No fibers descending to the LCN from levels rostral to the midbrain could be demonstrated in adult cats with the Nauta technique. A combined Nauta and electron microscopical investigation was performed on kittens operated on at different ages and allowed to survive varying times postoperatively. At the operations the LCN-axons were transected at midbrain level. The Nauta investigation demonstrated silver impregnation of degenerating LCN-neurons on the affected side of the same type as has been described recently in other neuronal systems following axonal transection. The ultrastructural study revealed electron dense degenerating dendrites and probably also nerve cells within the LCN. The dense degenerative changes were very similar to the dense degeneration in terminal boutons following transection of parent axons. The potential value of the findings for electron microscopical research in neuroanatomy is discussed. The results in terms of connections of the LCN are discussed in the light of known anatomical and physiological data of the LCN.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00236107
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  • 13
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    Electronic Resource
    Integration konvergierender Afferenzen in der bulbären Formatio Reticularis der Katze (1969)
    Springer
    Experimental brain research 7 (1969), S. 143-157 
    Details
    ISSN: 1432-1106
    Keywords: Reticular formation ; Convergence ; Inhibition ; Cat ; Chloralose
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 1. Ein konditionierender corticaler Reiz inhibiert den somatischen Startlereflex bei Katzen unter Chloralosenarkose für eine Dauer von mehr als 200 ms. Die Interaktionen zwischen beiden Reizen laufen in der bulbären und pontinen Formatio reticularis ab. 2. Dem Startlereflex liegt eine polysynaptische Erregungsschleife zugrunde, die die bulbäre und pontine Formatio reticularis durchzieht. Die Resistenz der reticulären Neurone gegenüber repetitiver Stimulation wurde als Kriterium ihrer funktionellen Lokalisation auf dem polysynaptischen Reflexbogen gewertet. 3. Die corticale Inhibition wird im Verlaufe der polysynaptischen Erregungsschleife zunehmend stärker. Neurone, die von den Startlereflexafferenzen direkt erregt werden, werden durch den corticalen Reiz nicht inhibiert. Dies schliebt eine präsynaptische Inhibition der reticulopetalen Fasersysteme aus.
    Notes: Summary 1. The startle reflex evoked by cutaneous stimulation in cats under chloralose anesthesia is inhibited for more than 200 ms by a conditioning cortical volley. The interaction between the cutaneous and the cortical volley takes place in the bulbar and pontine reticular formation. 2. The startle reflex involves a series of reticular neurones. Resistance to repetitive stimulation has been determined to evaluate the functional localization of each neurone within this polysynaptic path. 3. Inhibition following the cortical volley becomes increasingly more effective along the course of the polysynaptic path and is completed within 5–6 ms. Reticular neurones excited directly by the spino-reticular afferents are not inhibited, thus excluding a presynaptic inhibition of the spinoreticular fibres.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00235440
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  • 14
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    Electronic Resource
    Inhibitory and excitatory factors influencing the receptive fields of lamina 5 spinal cord cells (1969)
    Springer
    Experimental brain research 9 (1969), S. 284-306 
    Details
    ISSN: 1432-1106
    Keywords: Cutaneous receptive fields ; Spinal cord ; Cat ; Pain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Examination of cutaneous receptive fields (RFs) of lamina 5 cells in the lumbar spinal cord of decerebrate cats shows them to have three distinct zones with respect to mechanical and electrical stimulation. The mean response rate to both mechanical and electrical stimulation in zone 1 increases steadily up to the highest strengths used; in zone 2, surrounding zone 1 mainly proximally, mild stimuli reduce the mean rate, stronger stimuli increase it; in zone 3, mainly proximal to zone 2, all stimuli reduce the rate. Temporally, zone 1, electric shocks near threshold produce bursts of firing followed by inhibition. With increased stimulus strength, the bursts lengthen to a second or more. In zones 2 and 3, inhibition at all strengths is preceded at higher strengths by bursts of firing. Cold-blocking the spinal cord at lower thoracic levels reversibly increases the ongoing activity of these cells, increases the area of zones 1 and 2, and almost completely suppresses all inhibition. Stimulation of dorsal columns and threshold stimulation of distant dorsal roots inhibits ongoing and induced activity. Barbiturate decreases ongoing activity and the duration of firing produced by cutaneous electrical stimulation but does not decrease inhibition. These results are consistent with a model in which low-threshold fibres are excitatory only over a small central area of the RF of a lamina 5 cell (zone 1), high threshold fibres are excitatory over a larger area (zones 1 and 2), and low threshold fibres are inhibitory over the entire receptive field (zones 1, 2 and 3) with a slower time-course. This inhibition is tonically enhanced by descending influences in the decerebrate cat. It is suggested that the high and low threshold fibres correspond approximately to the small and large diametre fibres whose balance is the basis for the coding of pain in the theory of melzack and wall.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00235240
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  • 15
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    Electronic Resource
    Die Bedeutung der Vorderhirnkommissuren für die Koordination bilateraler EEG-Muster (1969)
    Springer
    Experimental brain research 7 (1969), S. 195-213 
    Details
    ISSN: 1432-1106
    Keywords: Corpus callosum ; EEG synchronization ; Homolateral sensory evoked potentials ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Spontaneous EEG-patterns and evoked potentials (EP's) of symmetrical cortical areas were recorded in chronic and acute cats before and after section of the corpus callosum, the commissura anterior and posterior and the massa intermedia. The spontaneous EEG was recorded without and with anesthesia, EP's after electrical stimulation of the fore-paws only during nembutal anesthesia. — No changes in the bilateral coordination of spontaneous and evoked EEG-patterns could be seen after commissurotomy (CT). The bilateral coherence of EEG-waves as revealed by cross-correlation is low already in the normal cats and does not change significantly after CT. The values of cross-correlation coefficients at T = ± 15 msec vary during one EEG-record between -0.25 and +0.25 in the somatosensory, suprasylvian and temporal areas (mean values slightly above 0). In the visual area occasionally positive values between 0.5 and 0.8 were seen, but also here a large variation was found in all animals and the mean values were below 0.1. No consistent phase shift between both sides was observed. EEG-patterns like spindles or arousal, still occurred together in both hemispheres after CT, the variability of their exact beginning or end was the same as in controls. Spontaneous spindles often lasted longer after section of the massa intermedia. Homolateral EP's in the somato-sensory area were still present after CT. Rhythmical afterdischarges could be restricted to the contralateral somato-sensory cortex even before CT.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00239029
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  • 16
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    Electronic Resource
    Functional organization of the vestibular afferents to the cerebellar cortex of frog and cat (1969)
    Springer
    Experimental brain research 9 (1969), S. 30-52 
    Details
    ISSN: 1432-1106
    Keywords: Climbing fibers ; Mossy fibers ; Vestibulo-cerebellar input ; Cat ; Frog ; Golgi cell inhibition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Field and unitary potentials evoked in the vestibulo-cerebellum of frog and cat following vestibular nerve stimulation were recorded with microelectrodes and correlated with their site of origin in the various layers of the cerebellar cortex. 2. In the frog, primary vestibular fibers project both as mossy and as climbing fibers onto the cerebellar auricular lobe. Secondary vestibulo-cerebellar fibers seem to end exclusively as mossy fibers in the auriculum. As a consequence of this dual projection, extra- and intracellular recordings from Purkinje cells in the auricular lobe show two kinds of responses to vestibular nerve stimulation: a) graded, repetitive firing mediated through mossy fiber-granule cell-parallel fiber pathways, and b) all-or-none burst responses caused by monosynaptic impingement of vestibular climbing fibers on Purkinje cells. 3. The field and unitary potentials evoked in the cat nodulus, flocculus and uvula following vestibular nerve stimulation are shown to be generated by mossy fibers exclusively. Considerable convergence of the two labyrinthine mossy fiber inputs to a given cerebellar area was found. 4. Interaction of contralateral and ipsilateral mossy fiber input at the level of the flocculus suggests that Golgi cell inhibition might operate not only as a simple inhibitory feedback loop, but also as a complex gating operator at the granule layer. 5. No short latency climbing fiber activation of Purkinje cells was observed following VIIIth nerve stimulation. Stimulation of the contralateral inferior olive evoked short latency climbing fiber EPSPs in Purkinje cells of the vestibulo-cerebellum. Suggestions are made as to the possible role of mossy and climbing fiber inputs to this area of the cerebellum.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00235450
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  • 17
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    Electronic Resource
    Pyramidal control of fusimotor neurons supplying extensor muscles in the cat's forelimb (1969)
    Springer
    Experimental brain research 9 (1969), S. 96-115 
    Details
    ISSN: 1432-1106
    Keywords: Pyramidal tract ; Fusimotor Neurons ; Forelimb ; Extensor ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effects of cortical stimulation upon dynamic and static sensitivities of the sensory endings in muscle spindles have been analyzed. 63 single afferent fibers from the muscle spindles of the forelimb extensors: M. flexor carpi radialis, M. flexor digitorum communis and M. palmaris longus were isolated in dorsal root filaments in 20 adult cats under chloralose-urethane anesthesia. They were identified by their response to stimulation of the median nerve. 1. Surface anodal repetitive stimulation of the anterior sigmoid gyrus was found to produce an enhancement of static response of single Group II fibers. Effective area was localized in a restricted region which corresponded to the forelimb motor area. The effect was obtained without any concomitant muscle contraction. Similarly, the stimulation increased the resting discharges of the Group Ia fibers from the same muscles. 2. Stimulation of the same area in the cerebral cortex was also found to increase the dynamic sensitivities of primary sensory endings. The increase was revealed by an enhancement of initial burst discharge during relaxation period of a twitch contraction caused by median nerve stimulation. 3. These results indicate that stimulation of the forelimb motor area has a facilitatory effect on both the static and dynamic fusimotor neurons innervating the muscle spindles of the test muscles. 4. The effects were reproduced in pyramidal tract preparations in which the brainstem was cut either at the level of the midbrain except for the cerebral peduncle or at the level of caudal medulla oblongata sparing the pyramid. 5. The threshold for the fusimotor effects was less than 1.3–1.5 times threshold of the pyramidal tract discharge, when the best spot for eliciting the fusimotor response was chosen. These results indicate that the effects of cortical stimulation are mainly mediated by the fast conducting pyramidal tract fibers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00238324
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  • 18
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    Electronic Resource
    Contrôle de l'activité des fibres fusimotrices dynamiques et statiques par la formation réticulée mésencéphalique chez le chat (1969)
    Springer
    Experimental brain research 9 (1969), S. 307-324 
    Details
    ISSN: 1432-1106
    Keywords: Muscle spindle ; Gamma motor control ; Mesencephalic reticular formation ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Effects of repetitive stimulation of the mesencephalic reticular formation (MRF) on the static discharge and dynamic sensitivity of muscle spindle primary endings (soleus muscle) were studied in cats anaesthetized with Halothane (Fluothane). By progressive increasing the depth of anaesthesia three different fusimotor effects could be observed: 1. A static effect; the static discharge of the primary endings was strongly increased; the response to phasic stretch was decreased or remained unaltered. 2. A dynamic effect; the dynamic sensitivity of the primary endings was powerfully increased while the rate of discharge under static conditions was only slightly augmented. 3. A depressant effect; the static discharge and the dynamic sensitivity of primary endings were decreased. Repeated stimulation elicited successive static and dynamic effects. No specific regions within the MRF could be related to a particular effect.
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    URL: http://dx.doi.org/10.1007/BF00235241
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  • 19
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    Electronic Resource
    Etude fonctionnelle du contrôle de l'activité des fibres fusimotrices dynamiques et statiques par les formations réticulées mésencéphalique, pontique et bulbaire chez le chat (1969)
    Springer
    Experimental brain research 9 (1969), S. 325-345 
    Details
    ISSN: 1432-1106
    Keywords: Muscle spindle ; Gamma motor control ; Reticular formations ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. During a progressive increase of Fluothane (Halothane) anaesthesia, repetitive stimulation of the mesencephalic retioular formation (MRF) produces several fusimotor effects — static, dynamic or depressant — on primary endings of soleus muscle spindles (Vedel et Mouillac-Baudevin 1969). 2. Transection of the brain immediately rostral to the site of stimulation may increase the dynamic effect but does not alter the static or the depressant effects. 3. A section of the rubrospinal tract does not modify the fusimotor effects elicited by stimulation of the MRF. 4. Transections of the spinal cord have shown that the pathways responsible for the transmission of these effects are mainly situated in the ipsilateral ventral and ventrolateral funiculi which contain the efferent fibers from the pontine reticular formation (PRF), from the bulbar reticular formation (BRF) and from the vestibular nucleus. 5. Contra and ipsilateral PRF stimulation produces the static fusimotor effect; contralateral stimulation from a small anterior region produces the dynamic effect. 6. Stimulation of the lateral part of the ipsilateral BRF elicits the dynamic effect while stimulation of the medial part elicits the static effect.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00235242
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  • 20
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    Electronic Resource
    Die asynchrone und lokal umschriebene Reizwirkung von Mittelfrequenz-Dauerströmen im Hypothalamus der Katze (1969)
    Springer
    Experimental brain research 9 (1969), S. 164-182 
    Details
    ISSN: 1432-1106
    Keywords: Emotional behaviour ; Hypothalamus ; Electricalstimulation ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. In order to compare the selective value of repetitive cathodal pulses of 8 c.p.s. and of continuous sine-wave alternating currents of 5000 c.p.s. (middle frequency current) when applied to brain tissue, explorations were made in the region of the hypothalamus that had yielded defence and/or flight reactions in earlier experiments. The region was explored by stimulating each point in turn with both current forms. At the same time measurement was made of the impedance of the brain tissue, and the effects produced by altering the time of rise of the middle frequency current on threshold of responses were also studied. The experiments were carried out on unanaesthetized, freely moving cats. 2. Both stimulation types produced affective (“emotional”) responses. The patterns elicited by low frequency cathodal pulse stimulation were often associated with stimulus-bound phasic muscle activity, i.e., flapping of ears, and twitching of whiskers, or, rotation of the head. Such extraneous motor effects were rarely obtained when continuous middle frequency currents were applied, and were tonic in character when present. 3. Mapping of reactive points revealed that the area producing defence or flight following middle frequency stimulation is smaller in size than the field delimited by means of repetitive cathodal pulse stimulation. These results strongly suggest that spread of current can be reduced by using middle frequency current stimulation. This apparently local (and hence highly selective) action is paralleled by a lower impedance of the brain tissue to the rapidly changing polarity of this current. 4. The hissing (and/or growling) associated with the defence pattern showed adaptation to suddenly rising middle frequency currents of 30 secs duration. An increase in threshold of hissing occurred when the time of rise of the current was prolonged. Flight, in contrast, was obtained at the same critical intensity regardless of the time of rise of current. 5. The nature of the stimulatory action of middle frequency current (examined in the peripheral nerve by Wyss) and the advantages presented by this new method of brain stimulation are briefly discussed.
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    URL: http://dx.doi.org/10.1007/BF00238329
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  • 21
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    Electronic Resource
    The lateral cervical nucleus in the cat III. An electron microscopical study after transection of spinal afferents (1969)
    Springer
    Experimental brain research 7 (1969), S. 32-50 
    Details
    ISSN: 1432-1106
    Keywords: Lateral cervical nucleus ; Spinal lesions ; Ultrastructural investigation ; Degenerating boutons ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructure of terminal degeneration within the lateral cervical nucleus (LCN) after transection of its spinal afferent fibers 2 days–2 years earlier is described. The degeneration after 2 days was of both the neurofilamentous and dense type. The highest number of degenerating terminals, about 15%, was found after 4–5 days. Then most of the degenerating boutons were of the dense type. The degenerating terminals had synaptic contact with cell bodies and dendrites of LCN-neurons. Removal of the degenerating boutons seemed to be effected by a phagocytic cell present in increased number compared to the normal LCN. In cases with long survival times an increase in the number of astroglial filaments was observed. In an animal where the spinal afferents to the LCN had been cut 2 years earlier a decrease in medium size of the neurons was observed. The amount of dendritic spines was also considerably smaller than normally.
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  • 22
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    Electronic Resource
    Inhibition in the medial geniculate body of the cat (1969)
    Springer
    Experimental brain research 7 (1969), S. 68-83 
    Details
    ISSN: 1432-1106
    Keywords: Medial geniculate body ; Inhibition ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Inhibitory activity in the cat medial geniculate body (MG) was examined by stimulating electrically and acoustically the input and output of the MG. 2. A longer and more profound depression of excitability occurs following a click-evoked potential in the MG than in the inferior colliculus (IC) in both anesthetized and unanesthetized states. Recovery is cyclic in the barbiturate MG preparation. 3. Electrical stimulation of the brachium of the inferior colliculus (BIG) evokes a field potential in the MG consisting of clearly distinguishable presynaptic and postsynaptic components. The presynaptic component recovers rapidly, while the postsynaptic component requires 100–200 msec for full recovery. This depression of excitability is localized within the MG since cortical ablation does not alter its occurrence. 4. Stimulation of the BIC mimics the effects of click stimulation on single units. Excitatory, inhibitory and reverberatory responses are evoked by the BIC shock. Suppression of single unit activity correlates with the depression of excitability following a BIC-evoked field response. 5. Cortical stimulation can evoke antidromic and trans-synaptic unit responses in the MG, as well as causing a variety of inhibitory effects and reverberation. In view of the fact that cortical ablation does not impair the recording of these responses to afferent stimuli, it is suggested that the cortical-evoked responses are at least partly mediated by antidromic conduction to MG. 6. Evidence is presented that inhibitory effects of both afferent and cortical stimulation are due to active inhibition of MG unit activity. Speculations are made as to the mechanisms producing inhibition and reverberation in the MG.
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    URL: http://dx.doi.org/10.1007/BF00236108
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  • 23
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    Electronic Resource
    Electronmicroscopic observations on the structure of the pontine nuclei and the mode of termination of the corticopontine fibres an experimental study in the cat (1969)
    Springer
    Experimental brain research 7 (1969), S. 95-110 
    Details
    ISSN: 1432-1106
    Keywords: Electron microscopy ; Pontine nuclei ; Experimental neuroanatomy ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The electron microscopical changes occurring in the pontine nuclei following unilateral lesions of the primary sensorimotor cortex have been studied in 7 cats with a survival time from 2–23 days. A description is also given of the fine structure of the pontine regions in receipt of the fibres. These regions are shown in Fig. 1. The study shows that the boutons are practically only in synaptic contact with dendrites. The bouton density on these is only 16%. The boutons are of the en passage and terminal type, with the latter as the most common (Figs. 4a-e). The synaptic vesicles are rounded or elongated. The formaldehyde fixed material had 17.8% boutons with vesicles of the elongated type; the material fixed with a mixture of formaldehyde and glutaraldehyde had only 11.5% of such boutons. The degenerating boutons show the dark type of reaction and the majority of the corticopontine fibres are of the type shown in Figs. 4d and 4e. Astrocytes and microglial cells participate in the removal of degenerating boutons and terminal fibres. Degenerating boutons are present even at the 23 day stage and some have apparently only started to degenerate.
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  • 24
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    Electronic Resource
    Eine faktorenanalyse von schwellen subcorticaler reizantworten (1969)
    Springer
    Experimental brain research 8 (1969), S. 79-96 
    Details
    ISSN: 1432-1106
    Keywords: Evoked potential thresholds ; Factor analysis ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Zur Beschreibung von Korrelationen zwischen zahlreichen elektrophysiologischen Daten aus verschiedenen Hirngebieten wurde eine Faktorenanalyse nach der Hauptachsenmethode gerechnet. Ausgangsmaterial dieser Analyse waren Schwellen subcortical ausgelöster und abgeleiteter Antwortpotentiale auf Einzelreize. Das resultierende Faktorenmuster ermöglicht ein quantitatives Konzept der Schwellendetermination subcorticaler Reizantworten und zugleich ein Modell von Funktionsbeziehungen zwischen einigen Hirnstrukturen. Die Reizungen und Ableitungen erfolgten bei 35 encéphale isolé-Katzen mit Hilfe bipolarer Elektroden in folgenden Arealen: Amygdala, Hippocampus, Septum, N. dorsomedialis Thalami, Hypothalamus posterior und Formatio reticularis mesencephali. Es wurden 435 Korrelationskoeffizienten zwischen den Schwellen von 30 subcorticalen Verbindungen gebildet und zum Zwecke einer Datenreduktion durch eine Matrix von 5 Faktoren reproduziert. 1. Jeder Faktor repräsentierte hohe Schwellenkorrelationen zwischen den efferenten Projektionen jeweils eines Kerngebietes. Demnach nimmt im allgemeinen die Aktivität des Reizortes den größten Einfluß auf die Schwelle eines Antwortpotentials. Diese Hypothese ist durch pharmakologische Untersuchungen belegt worden [27] 2. Kovariationen von Reizantworten mit identischen Ableiteorten ergaben sich ausnahmslos, wenn die Latenzzeiten mehr als 11 msec betrugen. 3. Zusätzlich zeigte die Faktorenmatrix Schwellenkorrelationen zwischen: a) den hypothalamischen Efferenzen und mehreren hippokampalen Afferenzen langer Latenz (positive Korrelationen) b) retikulo-limbischen Verbindungen und „primären” Efferenzen von Amygdala und Hippocampus (positive Korrelationen) c) Antwortpotentialen, die durch Reizung der Formatio reticularis, und solchen, die durch Reizung des N. Amygdalae ausgelöst waren (negative Korrelationen) d) den Efferenzen des N. dorsomedialis Thalami und limbischen Projektionen langer Latenz zur mesencephalen Formatio reticularis (positive Korrelationen) Die Interpretation dieser Zusammenhänge bestätigt und erweitert einige bekannte Modelle von Beziehungen zwischen subcorticalen Kerngebieten. Abschließend wird mit Rücksicht auf die Linearität der mathematischen Methode die Anwendbarkeit der Faktorenanalyse auf Schwellen von Reizantworten diskutiert.
    Notes: Summary In 35 cats (encéphale isolé) evoked responses were elicited and recorded with bipolar electrodes from the amygdala, hippocampus, septum, dorsomedial thalamic nucleus, posterior hypothalamus, and mesencephalic reticular formation. Correlations between the thresholds of responses in different areas following stimulation of other areas were described by a factor analysis according to the principal axis method. 435 coefficients of correlation were calculated and reproduced by a matrix of 5 factors for the purpose of data reduction. Each factor represented high threshold correlations between the efferent projections of one region, which suggests that the activity of the stimulated site exerts a major influence on the evoked potential threshold. This is supported by pharmacological studies [27, 49]. Covariations of responses recorded in the same nucleus were always found, if the latencies exceeded 11 msec. The factor matrix indicated threshold correlations between: the efferent projections of the hypothalamus and several long latency afferent projections to the hippocampus (positive correlations); reticulo-limbic connections and “primary” efferent connections of the amygdala and hippocampus (positive correlations); evoked potentials following reticular and amygdaloid stimulation (negative correlations); the efferent projections of the dorsomedial thalamic nucleus and long latency limbic projections to the mesencephalic reticular formation (positive correlations). The interpretation of these relationships confirms and extends some well known models of relations between subcortical regions. The applicability of factor analysis to evoked potential thresholds is discussed with regard to the linearity of the mathematical method.
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  • 25
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    Electronic Resource
    Interaction of defence and flight reactions produced by simultaneous stimulation at two points in the hypothalamus of the cat (1969)
    Springer
    Experimental brain research 8 (1969), S. 130-149 
    Details
    ISSN: 1432-1106
    Keywords: Emotional Behaviour ; Hypothalamus ; Electrical stimulation ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. The results presented in the present paper are an extension of preceding work devoted to exploration of the hypothalamic defence and flight fields using coaxial electrodes with small cathode. In 33 cats simultaneous stimulation was applied to two points which upon single stimulation had yielded defence, flight, or defence and flight respectively. Results were compared with those produced at either point alone. In 2 cats combined stimulation of a defence and a flight point was carried out with a stuffed cat present. 2. The latencies and rates of the vocal effects associated with defence (growling and hissing), and the latencies of flight (jump from the table) were measured. 3. Simultaneous stimulation of two points which had yielded defence, or of two points which had yielded flight resulted in facilitation (spatial summation) of the effects evoked: a more complete defence response associated with decrease of the latencies and increase in the rates of the vocal effects; decrease of flight latencies and increase of flight impetuosity. 4. Simultaneous stimulation of a defence point which had yielded growling at lower threshold than hissing, and of a point which had yielded flight resulted in facilitation of hissing. Growling and flight were often suppressed; when they occurred, latencies were lengthened and growling rates were increased somewhat. 5. Stimulation of a defence point with a dummy present produces striking (fending off). Simultaneous stimulation of a flight point resulted in facilitation of both hissing and striking. 6. It is concluded that the complex patterns obtained when defence is combined with flight are the result of facilitatory and inhibitory interaction between the elements of the individual patterns.
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    URL: http://dx.doi.org/10.1007/BF00234535
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  • 26
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    Electronic Resource
    Räumliche summation und hemmungsvorgänge im receptiven feldzentrum von retina-neuronen der katze (1969)
    Springer
    Experimental brain research 8 (1969), S. 37-52 
    Details
    ISSN: 1432-1106
    Keywords: Retinal Ganglion Cells ; Spatial Summation ; Center Inhibition ; Dynamic Organisation of Receptive Fields ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 1. An retinalen Ganglienzellen der Katze wurde die räumliche Summation im receptiven Feldzentrum (KFZ) bei Dunkeladaptation und Helladaptation durch mittelpunktzentrierte Lichtreize verschiedener Flächengrößen untersucht. Als Kriterium dienten die Entladungsraten der ersten 200 und 500 msec nach Licht-an oder Licht-aus. Das Summationsverhalten wurde sowohl für Einzelneurone als auch gruppenstatistisch für die beiden Neuronen-Systeme B (on-Zentrum) und D (off-Zentrum) untersucht. 2. Die räumliche Summation ist auf den inneren Bereich des RFZ beschränkt: bei on-Zentrum-Neuronen steigt die Entladungsrate nur bis zu Reizflächen, die etwa 1/5 der Fläche des RFZ belichten, bei off-Zentrum-Neuronen bis zu Reizflachen von ca. 1/10 des RFZ. Bei Variation der Reizfläche zwischen 20 und 100% der Fläche des RFZ bleibt das Entladungsniveau konstant (asymptotischer Verlauf der Summationskurve). 3. Die Begrenzung der räumlichen Summation auf einen kleinen Bereich des RFZ beweist eine bereits im Feldzentrum wirksame Hemmung. Diese Zentrum-Inhibition begrenzt die Erregungssummation im RFZ bei zunehmender Flächengröße des Lichtreizes. 4. On- und off-Zentrum-Neurone unterscheiden sich in beiden Adaptationszuständen in der Höhe des Entladungsniveaus. Die Entladungsraten der on-Zentrum-Neurone nach Licht-an übertreffen um ein Mehrfaches die Entladungsraten der off-Zentrum-Neurone nach Licht-aus. Die Unterschiede sind gruppenstatistisch hoch signifikant. Die interneuronale Variabilität der Entladungsraten ist bei den onZentrum Neuronen erheblich geringer als bei den off-Zentrum-Neuronen. 5. Dunkel -und Helladaptation führt zu signifikantem Unterschied der Entladungsraten: bei Helladaptation liegt die Impulsrate beider Neuronentypen höher als bei Dunkeladaptation und der Summationsbereich ist um 5–10% größer. 6. Für die mathematische Beschreibung der Summationsverläufe ist die Hyperbel besser geeignet als die logarithmische und Potenzfunktion. Logarithmus- und Potenzfunktionen beschreiben den konstanten asymptotischen Teil der Summationskurven ungenügend und eigenen sich nur für den Kurventeil im innersten Summationsbereich. Die Bedeutung der Befunde für eine dynamische Interpretation der visuellen Feldorganisation und mögliche Beziehungen zur lateralen Umfeldhemmung werden diskutiert.
    Notes: Summary 1. Spatial summation of suprathreshold light stimuli within receptive field centers (RFZ) of retinal ganglion cells was investigated during dark and light adaptation in cats. The mean discharge rates for 200 and 500 msec following light on or off were the computed response criteria. The summation effects were analyzed for single neurones and statistically for grouped neuron populations of the two neuronal subsystems B (on-center-neurones) and D (off-center-neurones). 2. Spatial summation is restricted to a small part of the RFZ. On-centerneurones increase their on-discharge rates with increasing spot sizes, only if the stimulus illuminates less than 1/5 of the RFZ. The summating area of the off-centerneurones is smaller (about 1/10 of the RFZ). 3. The limitation of spatial summation to a small part of the RFZ indicates the existance of inhibition within the RFZ. This center-inhibition sets a constant limit for excitation summation in the RFZ. 4. The mean neuronal response rates for the 2 subsystems show significant differences: The on-discharges of the on-center-neurones exceed the off-discharges of the off-center-neurones by a factor of 3–5. These highly significant differences occur at both adaptation levels and are not due to different spontaneous activity. Interneuronal response variability of the off-center-neurones was twice as large as that of the on-center-neurones. 5. Change from dark to light adaptation had only a small but significant influence on summation properties. The poststimulus discharge rates were higher during light adaptation and the summating area was slightly larger (about 5–10%). 6. A comparative curve fitting procedure for three suitable mathematical functions revealed that the hyperbola describes the neuronal summation curves better than a logarithmic or power function. The latter do not fit the constant asymptotic part of the curve. The significance of the results for a dynamic interpretation of the organisation of visual receptive fields is discussed.
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  • 27
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    Räumliche summation im receptiven feldzentrum von neuronen des geniculatum laterale der katze (1969)
    Springer
    Experimental brain research 8 (1969), S. 53-65 
    Details
    ISSN: 1432-1106
    Keywords: Lateral geniculate body ; Spatial summation ; Off-center-characteristics ; Geniculate transfer ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 1. Die räumliche Summation im receptiven Feldzentrum von Neuronen des Corpus geniculatum laterale (CG-L) wird beschrieben und mit entsprechenden Untersuchungen an retinalen Ganglienzellen verglichen. Neben größerer interneuronaler Variabilität ergeben sich ausgeprägtere Unterschiede der Summationseigenschaften der on-und off-Zentrum-Neurone. Der effektive Summationsbereich von etwa 1/5 der Fläche des RFZ ist in Retina und CGL etwa gleich. 2. Die on-Zentrum-Neurone des CGL zeigen in beiden Adaptationszuständen einen ähnlichen Summationsverlauf wie in der Retina. Das Entladungsnieau ist im CGL jedoch erheblich geringer und nicht durch Unterschiede in der Spontanaktivität zu erklären. 3. Die Mehrzahl der off-Zentrum-Neurone des CGL zeigt bei DA inverse Summationsverläufe wie in der Retina: durchgehende Verminderung der Entladungsrate der off-Antworten bei Vergrößerung der Reizfläche im RFZ. Eine kleine Gruppe zeigt einen parabelförmigen Summationsverlauf mit Entladungszunahme bis zu Reizflächen von 10–30% der Fläche des RFZ und darauffolgender Entladungsminderung. Bei Helladaptation zeigen fast alle off-Zentrum-Neurone diesen Parabelverlauf. Das durchschnittliche Entladungsniveau ist von dem retinaler offZentrum-Neurone nicht signifikant verschieden. 4. Die interneuronale Variabilität der Summationsvorgänge im RFZ von CGLNeuronen ist gegenüber den retinalen Ganglienzellen deutlich größer. Dies gilt insbesondere für die off-Zentrum-Neurone. Das Summationsverhalten von CGLNeuronen läßt sich daher nicht wie in der Retina durch einen Funktionstyp beschreiben. 5. Die Befunde sprechen für eine Transformation des retinalen Eingangs der off-Zentrum-Neurone im CGL, während die on-Zentrum-Neurone außer der bekannten Frequenzuntersetzung keine wesentliche Umformung erkennen lassen.
    Notes: Summary 1. Spatial summation in the receptive field center of neurones of the lateral geniculate body (CGL) is limited by inhibition to a small part of field center. Variations of stimulus size are only effective if the stimulus is smaller than about 1/5 of the area of receptive field center. Thus, the active summating area of the field center in the CGL corresponds to that of the retina. Geniculate neurones, however, show less homogeneous responses and the summation properties of the two neuronal subsystems (on-center-and off-center-cells), show greater differences than in the retina. 2. The form of summation curves for the on-center-neurones of the CGL is similar to those of the retina at both adaptation levels. However, the average responses rates in the CGL are considerably lower. This is not due to differences of spontaneous activity. 3. The summation characteristics of off-responses of off-center-neurones of the CGL are quite different from those in the retina. In dark adaptation the majority of CGL neurones respond with decreasing discharge rates to increasing spot-sizes within the field center. A small number show an initial increase of discharge rates up to stimulus sizes of about 1/10 of the receptive field center before a decrease occurs. This parabolic summation type is typical for most off-center-neurones in light adaptation. The mean discharge levels are the same as those of the retinal offcenter-neurones. 4. The higher interneuronal variability of summation curves especially of the off-center-neurones of the CGL indicates a more complex determination of the discharge properties of CGL neurones. This functional differentiation of single neurones is congruent with the more complex structural and synaptic organisation in CGL. 5. With respect to spatial summation, the results indicate a transformation of the retinal input of the off-center-neurones at the geniculate level, whereas the oncenter-neurones are nearly unchanged.
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    Electronic Resource
    Langfristige Verträglichkeitsprüfung mit Benperidol an der Katze (1969)
    Springer
    Psychopharmacology 14 (1969), S. 164-166 
    Details
    ISSN: 1432-2072
    Keywords: Benperidolum ; Cat ; Extrapyramidal Side Effect ; EEG ; Toxicity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Daily doses of 1–10 mg Benperidol were given perorally to cats during 26 months. The general behaviour and the EEG were unchanged during the treatment, in particular no signs of dyskinesia were observed. After discontinuation of the administration, the behaviour and the EEG of the animals stayed normal. Thus no lasting and irreversible side effects could be observed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00403690
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  • 29
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    Electronic Resource
    Effects of LSD on the spontaneous and evoked activity of retinal and geniculate ganglion cells (1969)
    Springer
    Psychopharmacology 15 (1969), S. 382-391 
    Details
    ISSN: 1432-2072
    Keywords: LSD ; Retina ; LGN ; Single Unit Activity ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effect of LSD 25 (i. v. injection) on the spontaneous and evoked activity of the visual system was investigated in cats. 50 γ/kg did not change significantly the ERG and the visual cortical evoked potential. The spontaneous discharge rate of 14 out of 21 retinal ganglion cells showed an increase which reached its maximum within 20–30 min and which could still be present 1 hour following the injection. One third of the retinal units showed a slight depression of their spontaneous dischaRge rate with about the same time course. Single units of the LGN showed about the same behaviour. The response to light stimulation was slightly increased in some units and light induced inhibition was slightly shortened. The possible mechanism of the LSD-effect on retinal ganglion cell activity is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00403713
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  • 30
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    Electronic Resource
    Responses of neurones in cat's abducens nuclei to horizontal angular acceleration (1969)
    Springer
    Pflügers Archiv 309 (1969), S. 285-309 
    Details
    ISSN: 1432-2013
    Keywords: Labyrinthine Stimulation ; Types of Abducens Neurones ; Frequency Analysis ; Cat ; Labyrinthreizung ; Abducensneurone ; Frequenzanalyse ; Katze
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Single cell activity was recorded extracellularly from neurones in cat's abducens nuclei in unanesthetized, decerebrate preparations. Two types of neurones were found. i) The motoneurones (type IIA) increased their firing linearly or exponentially to contralateral constant angular accelerations and decreased firing to ipsilateral rotation. The increased frequency was maintained at a constant level without any sign of adaptation. This constant level of maximum frequency was proportional to the logarithm of the acceleration applied. No significant differences of the frequency responses of tonic and silent motoneurones were found. The conduction velocities of the axons of spontaneously firing type IIA cells were slower than in silent neurones. Electrical stimulation of the contralateral VIIIth nerve led to activation of the type IIA cells; stimulation of the ipsilateral nerve resulted in inhibition of both spontaneous discharge and antidromic invasion of the motoneurones. ii) The type IA units increased their firing rate to ipsilateral rotation and ceased to discharge in response to contralateral rotation. They never were excited antidromically by stimulation of the VIth nerve. However, they were excited by stimulation of the ipsilateral VIIIth nerve. Their possible functional role in the vestibulo-ocular system was discussed.
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    URL: http://dx.doi.org/10.1007/BF00587754
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  • 31
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    Die Rolle „spezifischer” und unspezifischer Afferenzen für den Antrieb der Atmung, untersucht durch Reizung und Blockade von Afferenzen an der decerebrierten Katze (1969)
    Springer
    Pflügers Archiv 312 (1969), S. 189-205 
    Details
    ISSN: 1432-2013
    Keywords: Cat ; Decerebration ; Afferents to Respiratory Centers ; Medulla Oblongata ; Reticular Formation ; Katze ; Decerebrierung ; Afferenzen zu Atemzentren ; Medulla oblongata ; Formatio reticularis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung An 11 intercolliculär decerebrierten Katzen wurde geziegt, daß Kälteblockade eines eng umschriebenen Feldes auf der ventralen Oberfläche der Medulla oblongata, wie früher für anaesthesierte Tiere beschrieben, zu Atemstillstand führt, wenn die kontralaterale Stelle auf der Medulla oblongata, die Sinusnerven und die Vagi ausgeschaltet sind. Zu Atemstillstand kam es auch, wenn statt der Kälteblockade 2% Novocain durch lokale Superfusion bei gleichzeitiger Gegenspülung der Umgebung mit künstlichem Liquor angewandt wurde, oder wenn ein mit 1% Novocain getränkter Tupfer lokal aufgelegt wurde. Außerdem führte Kälteblockade zu Atemstillstand, wenn durch kontinuierliche auch während der Kälteblockade anhaltende elektrische Reizung eines N. femoralis oder hinterer Lumbalwurzeln an decerebrierten Katzen oder des Hypothalamus an einer anaesthesierten Katze Steigerungen der Ventilation ausgelöst worden waren. Elektrische Reizung eines Sinusnerven führte zu Atemsteigerungen. Bei Sinusnervenreizung während eines durch Kälteblockade ausgelösten Atemstillstands kam es zu rhythmischer Atmung. Aus diesen Untersuchungen wird geschlossen, daß mit der Ausschaltung der beschriebenen Felder auf der ventralen Oberfläche der Medulla oblongata am sonst desafferentierten Tier die Gesamtheit der für die zentrale CO2-Empfindlichkeit verantwortlichen Strukturen erfaßt ist, daß nach Ausschaltung der zentralen und der peripheren Chemosensibilität eine unspezifische Aktivierung der Atmungszentren unwirksam ist und daß die Atmungszentren zur Ausbildung einer rhythmischen Atmung von spezifischen Antrieben abhängig sind.
    Notes: Summary It was shown in 11 decerebrated cats, that cooling of a small and well defined area on the ventral surface of the medulla will cause respiratory arrest if the contralateral area of the medulla, the vagi and sinus nerves are eliminated. This confirms earlier observations obtained in anesthetized cats. Apnea was also produced by local superfusion of 2% procain with simultaneous flushing of the immediate surrounding area with mock spinal fluid. Local application of a small sponge soaked with 1% procain had the same effect. Electrical stimulation of femoral nerves or posterior roots which results in hyperventilation on the decerebrated cat failed to show any effect during periods of cold blockade. There was no respiratory response to direct stimulation of the hypothalamus in an anesthetized cat during cooling. Electrical stimulation of one sinus nerve caused an increase of ventilation. Sinus nerve stimulation during apnea induced by cold blockade resulted in rhythmical respiration. It is concluded from these experiments: Blocking of the area under discussion on the ventral surface of the medulla, inhibits all structures responsible for the central CO2-sensitivity in the deafferentiated animal. There was no response to non-specific stimuli of the respiratory center after elimination of central and peripheral chemosensitivity. The respiratory centers apparently depend on specific stimuli to support rhythmical respiration.
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  • 32
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    Relevance of sodium transport pool measurements in toad bladder tissue for the elucidation of the mechanism whereby hormones stimulate active sodium transport (1969)
    Springer
    Pflügers Archiv 313 (1969), S. 197-221 
    Details
    ISSN: 1432-2013
    Keywords: Toad Bladder ; Sodium Transport Pool ; Aldosterone ; Insulin ; Vasopressin ; Krötenblase ; Natrium-Transport-Pool ; Aldosteron ; Insulin ; Vasopressin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The size of toad bladder sodium transport pool, defined as that amount of sodium of apical origin and recovered in tissue at equilibrium, was compared with sodium transport rate, derived from short-circuit current read immediately before tissue analysis. Provided certain precautions be taken, the relationship between both variables can be described by a curve starting at the intersect ofX (pool, in μEq) andY (transport, in μEq/hr) axes, with a tendency forX to increase faster thanY. Assuming sodium transport pool forms one compartment, its calculated half-life averages 2–3 min. sodium transport pool measurements are thought to shed light on mechanism of sodium transport by toad bladder because pool size was large with respect to transport rate when tissue was exposed to several inhibitors of sodium transport. Conversely, upon stimulation of activity of (substrate — depleted) preparations by glucose, a relative reduction of pool size was observed. Aldosterone, vasopressin (and adenosine 3′,5′-phosphate) increased sodium pool size and transport rate, proportionately; insulin stimulated sodium transport more than it increased pool size. Thus, insulin presumably exerts its effect at the sodium “pump” while such a site of action need not be postulated for aldosterone and vasopressin: these 2 hormones would instead induce, permeability changes faciliting sodium movement at the apical border of toad bladder epithelial cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00586744
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    Electronic Resource
    Defence, attack, and flight elicited by electrical stimulation of the hypothalamus of the cat (1969)
    Springer
    Experimental brain research 8 (1969), S. 113-129 
    Details
    ISSN: 1432-1106
    Keywords: Emotional behaviour ; Hypothalamus ; Electrical stimulation ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Affective behaviour patterns produced by electrical stimulation of the hypothalamus were studied in unanaesthetized, freely-moving cats. Bipolar stimulation with coaxial electrodes and small cathode was used to elicit defence, attack or flight. The development of these responses was studied by varying stimulation strength. In some experiments a stuffed animal was introduced in order to study the reactions of the cat to changes in the environment during stimulation. 2. The following responses were evoked at threshold intensity: (i) growling reaction; (ii) hissing reaction; (iii) two types of flight — type a preceded by hastily looking to and fro as if in search of an exit, type b preceded by inspection of surroundings, in most cases associated with sniffing. 3. Increasing stimulation 1.5 times threshold often yielded combined patterns. At points yielding the growling reaction a defence response in which growls alternated with hisses was obtained. The points yielding flight type a sometimes yielded hissing followed by flight. Increasing stimulation at hissing points yielded either a defence reaction or the combined effect hissing-flight. 4. The growling reactions were obtained from the tuber region. The hissing responses were obtained from points above the tuber. The flight reactions, type a, were produced from the intermediate zone extending from the level of the preoptic area to the mamillary bodies and type b from the caudo-lateral hypothalamus. 5. The reactions of the cats to a dummy during stimulation varied depending on the type of response which had been evoked in the absence of the dummy. The defence reaction was converted into threatening and striking of the dummy, the combined effects into threatening, striking or biting, culminating in sudden flight. The dummy was ignored during stimulation of points yielding flight type a, but examined by sniffing during stimulation of points yielding flight type b.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00234534
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    Electronic Resource
    Evidence for mediated transport of chloride in cat cerebral cortex in vitro (1969)
    Springer
    Experimental brain research 8 (1969), S. 219-231 
    Details
    ISSN: 1432-1106
    Keywords: Cerebral cortex in vitro ; Chloride transport ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The kinetics of the uptake of chloride by slices of cat cerebral cortex incubated in vitro have been studied for a wide range of concentrations of chloride and potassium in the incubation media. 1. In studies with 36Cl at a constant concentration of external K+, the rate of entry of chloride into slices of cat cerebral cortex (after equilibration with the fluid of the extracellular space) followed Michaelis-Menten kinetics with Vmax=7.7 μmoles/g/min and Km=245 mM. The kinetic data so described differ significantly from a curve describing simple diffusion (P 〈 0.02). 2. A clear dependence on concentration of K+ in the incubation medium was demonstrated. When external chloride was held constant at 6.8 mM and concentrations of potassium were varied over a range of 27–100 mM, the apparent rate of entry of chloride followed Michaelis-Menten kinetics with Vmax=0.191 μmoles/ g/min and Km=30.3 mM. 3. Under similar equilibrium conditions, the rate of influx of chloride was not statistically different from the rate of efflux, and the value for extracellular space (355 μl/g) derived by extrapolation from efflux data was of an identical order of magnitude to the value (352 μl/g) obtained from influx data. These values are essentially identical to those previously determined for chloride space of cat cerebral cortex in vivo (Bourke, Greenberg and Tower 1965). 4. The total, membrane-delimited content of chloride in cerebral cortex, as defined in these studies in vitro, was a function of the concentration of K+ in the incubation medium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00234250
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    Electronic Resource
    Studies of the development and subsequent reduction of swelling of mammalian cerebral cortex under isosmotic conditions in vitro (1969)
    Springer
    Experimental brain research 8 (1969), S. 232-248 
    Details
    ISSN: 1432-1106
    Keywords: Cerebral cortex in vitro ; Edema ; Fluid compartmentation ; Chloride transport ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ionic parameters of incubation media which foster both the development and subsequent reduction of swelling of slices of cerebral cortex under isosmotic conditions of incubation in vitro are described. A linear relationship between increasing chloride concentrations in incubation media and progressive swelling of tissue slices (under conditions of constant temperature and K+ concentrations and isotonicity of incubation media) is demonstrated. Subsequent reduction of chloride concentration in incubation media together with reciprocal replacement by isethionate is associated with significant and characteristic reduction in the volume of tissue swelling when all other conditions of incubation, including isotonicity of the media, are kept constant. The ionic composition of the fluid of swelling under different conditions of incubation is derived together with the ionic composition and expected transmembrane potentials of the neuronal compartment of cerebral cortex in vitro. Mechanisms involved in the development and subsequent reduction of swelling of cerebral cortex in vitro are discussed, and proposals for possible clinical applications are suggested.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00234251
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  • 36
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    Verbesserung der Resorption von Helveticosid und Helveticosol durch Substitution der Hydroxylwasserstoffe an der Digitoxose (1969)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 262 (1969), S. 73-86 
    Details
    ISSN: 1432-1912
    Keywords: Strophanthidine Derivatives ; Toxicity ; Absorption ; Guinea-Pig ; Cat ; Strophanthidinderivate ; Toxicität ; Resorption ; Meerschweinchen ; Katze
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Es wurde die Wirksamkeit verschiedener Ester und Äther von Helveticosid und Helveticosol bei i.v. und intraduodenaler Zufuhr an Katzen und Meerschweinchen geprüft. 1. Bei i.v. Dauerinfusion waren Helveticosol und seine Derivate bei Meerschweinchen etwa doppelt so wirksam wie die analogen Helveticosidverbindungen. Bei der Katze bestand kein Unterschied. Die Monomethyläther Cymarin und Cymarol waren gleich oder sogar stärker wirksam, alle übrigen Derivate deutlich schwächer als die Ausgangssubstanzen. 2. Die tödlichen Dosen bei intraduodenaler Injektion lagen beim Meerschweinchen für einige Substanzen in gleicher Größenordnung oder niedriger als die Titer bei i.v. Infusion. Diese hohe enterale Wirksamkeit kann bei Helveticosid und seinen Derivaten durch eine Reduktion zu dem wirksameren Helveticosol, bei Estern außerdem durch eine Hydrolyse zu wirksameren Glykosiden vorgetäuscht werden. 3. Bei intraduodenaler Infusion an Katzen waren alle geprüften Ester und Äther wirksamer als Helveticosid und Helveticosol. Die aus dem Verhältnis der toxischen Dosen bei i.v. und intraduodenaler Infusion berechnete enterale Wirksamkeit lag zwischen 20 und 50%. 4. Unterschiede in der Dauer der intraduodenalen Infusion bei Katzen lassen sich berücksichtigen, wenn man von der theoretischen Annahme einer exponentiellen und vollständigen Resorption ausgeht und die Halbwertszeit für die Resorption berechnet. Die minimale Resorptionsgeschwindigkeit lag bei einigen Derivaten in gleicher Größenordnung wie bei Digoxin und Digitoxin. Es wird auf den Unterschied zwischen der auf Grund der pharmakologischen Wirkung bestimmten relativen enteralen Wirksamkeit und der Resorptionsquote hingewiesen. Letztere ist für die Verläßlichkeit der therapeutischen Wirkung eines Glykosids bei oraler Gabe maßgebend.
    Notes: Summary The efficacy of several esters and ethers of Helveticosid and Helveticosol was assayed by intravenous and intraduodenal administration to cats and guinea-pigs. 1. In guinea-pigs, Helveticosol and its derivatives were approximately twice as active on intravenous infusion as the analogous derivatives of Helveticosid; in cats there was no significant difference. The monomethylethers Cymarin and Cymarol were equally or slightly more potent, all other derivatives were weaker than the original compound. 2. In guinea-pigs the lethal doses of some compounds on intraduodenal injection were equal to or even lower than those on intravenous infusion. This may partly be accounted for by a reduction of Helveticosid and its derivatives to the more potent Helveticosol analogues, partly by a hydrolysis of the esters, yielding compounds of higher activity. 3. On intraduodenal infusion in cats, all the investigated esters and ethers were more active than Helveticosid and Helveticosol. The relative enteral activity calculated from the ratio of the toxic doses on intravenous and intraduodenal infusion varied between 20 and 50%. 4. Due to a delayed absorption from the gastrointestinal tract, the toxic dose falls with a reduced speed of intraduodenal infusion. Assuming an exponential and complete absorption, the half time of absorption was calculated. For some of the compounds investigated, the speed of absorption was comparable to that of Digoxin and Digitoxin. The difference between the relative enteral activities determined by comparing equiactive doses on enteral and parenteral administration and the percentages of the glycosides which are absorbed from the gastrointestinal tract is pointed out. The latter is of prime importance for obtaining reproducible effects after enteral administration.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00536819
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    Electronic Resource
    Procedure for double antibody immunoassay of insulin (1969)
    Springer
    Acta diabetologica 6 (1969), S. 371-388 
    Details
    ISSN: 1432-5233
    Keywords: Insulin ; Insulin antibodies ; Insulin assay ; Laboratory technique
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01548060
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    Electronic Resource
    Variaciones diurnas de la eliminación de insulina en orina (1969)
    Springer
    Acta diabetologica 6 (1969), S. 197-205 
    Details
    ISSN: 1432-5233
    Keywords: Diurnal variations ; Food intake ; Glucose load ; Insulin ; Tolbutamide test
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Resume On a étudié l'effet de la lumière et de la période d'ingestion des aliments sur l'élimination d'insuline par les urines. On peut démontrer l'existence d'un rythme circadien et la présence de deux facteurs de régulation pour cette élimination. On présente quelques hypothèses concernant ces phénomènes.
    Abstract: Resumen Se estudió el efecto que sobre la eliminación de insulina urinaria ejercen los períodos de luzoscuridad y el horario de administración del alimento. Se demuestra la existencia de un ritmo circadiano de eliminación de dicha hormona, describiéndose dos reguladores del mismo. Se hacen especulaciones fisiopatológicas acerca de su significado.
    Notes: Riassunto E' stato studiato l'effetto della luce e del periodo di ingestione del cibo sull'eliminazione di insulina nelle urine. Si può dimostrare l'esistenza di un ritmo circadiano e la presenza di due fattori di regolazione per questa eliminazione. Vengono presentate alcune ipotesi concernenti questi fenomeni.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01548049
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    Proprietà insulino-stimolanti della glibenclamide (HB 419) in soggetti normali. Studi comparativi con la tolbutamide (1969)
    Springer
    Acta diabetologica 6 (1969), S. 283-298 
    Details
    ISSN: 1432-5233
    Keywords: Glybenclamide ; Insulin ; Insulin secretion ; Sulfonylureas ; Tolbutamide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Resume Les effets métaboliques de la glybenclamide et de la tolbutamide ont été étudiés chez deux groupes de sujets normaux traités avec des doses comparables des deux sulphanylurées. En rapport aussi à la dose de 1:400, la glybenclamide a démontré une activité insuline-sécrétive bien majeure de celle de la tolbutamide. La réponse insulinique a été suivie par une rapide et prolongée diminution des NEFA sériques et par un moins persistant effet hypoglycémique. Les effets métaboliques de l'HB 419 sont encore évidents 10–12 heures après l'administration du médicament, tandis que l'activité de la tolbutamide est terminée géneralement entre 4–6 heures. Quand l'administration des médicaments a été pratiquée en concomitance avec une charge veineuse de glucose, le coéfficient de Conard était élevé d'une façon significative par toutes les deux sulphanylurées.
    Abstract: Resumen Los efectos metabólicos de la glibenclamida y de la tolbutamida han sido investigados en dos grupos de sujetos normales tratados con dosis comparables de las dos sulfanilúreas. Inclusive en una relación de dosificación de 1:400, la glibenclamida ha demostrado una actividad insulinosecretora mucho mayor de la tolbutamida. La respuesta insulínica ha sido seguida de una disminución pronta y prolongada de los NEFA séricos y de un efecto hipoglucemiante menos persistente. Los efectos metabólicos del HB 419 son aún evidentes a las 10–12 horas después de la administración del medicamento, mientras la actividad de la tolbutamida es anulada por lo general dentro de 4–6 horas. Cuando la suministración de los medicamentos ha sido practicada en coincidencia con una carga venosa de glucosa, el coeficiente de Conard apareció significativamente elevado por ambas sulfanilúreas.
    Notes: Riassunto Gli effetti metabolici della glibenclamide e della tolbutamide sono stati indagati in 2 gruppi di soggetti normali trattati con dosi comparabili delle due sulfaniluree. Anche in un rapporto di dosaggio di 1:400, la glibenclamide ha mostrato un'attività insulino-secretiva assai maggiore di quella della tolbutamide. La risposta insulinica è stata seguita da una pronta e prolungata diminuzione dei NEFA serici e da un meno persistente effetto ipoglicemico. Gli effetti metabolici del-l'HB 419 sono ancora evidenti 10–12 h dopo la somministrazione del farmaco mentre l'attività della tolbutamide si annulla generalmente entro 4–6 h. Quando la somministrazione dei farmaci è stata praticata in coincidenza con un carico venoso di glucosio, il coefficiente di Conard è apparso significativamente innalzato da entrambe le sulfaniluree.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01548054
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    Electronic Resource
    Studies on the transport of insulin antibodies across the placenta to the fetus and their effect on the fetal pancreatic islet system (1969)
    Springer
    Acta diabetologica 6 (1969), S. 573-584 
    Details
    ISSN: 1432-5233
    Keywords: Insulin ; Insulin antibodies ; Islets of Langerhans ; Placenta ; Transport
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Resume Ce travail est la continuation des communications préliminaires sur la résistance insulinique des nouveaux-nés de mères insuline-résistantes. Les recherches ont été conduites sur cobayes et sur sujets humains. Les AA. ont démontré que les anticorps anti-insuline passent dans la circulation fœtale et provoquent l'apparition d'une insuline-résistance passive qui va disparaître dans les premières semaines de la vie. Les anticorps contre l'insuline bovine lient en partie l'insuline endogène des cobayes, ce qui est mis en evidence par l'hyperglycémie élevée des cobayes jeunes nées de mères insuline-résistantes. Les anticorps anti-insuline n'ont aucun effet important sur la structure du pancréas des cobayes dans la période périnatale.
    Abstract: Resumen Este trabajo representa la continuación de las comunicaciones preliminares sobre la resistencia insulínica que presentan las personas nacidas de madres insulino-resistentes. Las investigaciones han sido efectuadas en cobayas y hombres. Se ha demostrado que los anticuerpos anti-insulina pasan al círculo fetal, provocando la aparición de insulino-resistencia pasiva, que desaparece durante las primeras semanas de vida. Los anticuerpos contra la insulina bovina ligan en parte la insulina endógena de cobayas, como lo demuestra la hiperglucemia elevada de las cobayas jóvenes nacidas de madres insulino-resistentes. Los anticuerpos anti-insulina no ejercen ningún efecto apreciable sobre la estructura del páncreas de las cobayas durante el período peri-natal.
    Notes: Riassunto Questo lavoro rappresenta la continuazione delle comunicazioni preliminari sulla resistenza insulinica dei nati di madri insulino-resistenti. Le ricerche sono state condotte su cavie e su uomini. E' stato dimostrato che gli anticorpi anti-insulina passano nel circolo fetale inducendovi la comparsa di una insulino-resistenza passiva che scompare nelle prime settimane di vita. Gli anticorpi contro l'insulina bovina legano in parte l'insulina endogena di cavie, come è evidenziato dall'elevata iperglicemia delle cavie giovani nate da madri insulino-resistenti. Gli anticorpi anti-insulina non esercitano alcun effetto di rilievo sulla struttura del pancreas delle cavie nel periodo perinatale.
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    URL: http://dx.doi.org/10.1007/BF01548073
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    Electronic Resource
    Insulin allergy. Clinical and immunological effects of specific desensitization (1969)
    Springer
    Acta diabetologica 6 (1969), S. 796-808 
    Details
    ISSN: 1432-5233
    Keywords: Desensitization ; Immunoglobulins ; Insensitivity ; Insulin ; Insulin allergy ; Insulin antibodies ; Macroglobulins ; Porcine insulin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Resume Cinq patients atteints d'allergie à l'insuline ont été désensibilisés par de l'insuline de porc selon la méthode d'Urbach et Gotlieb. Le diagnostic d'allergie à l'insuline a été posé sur la base des manifestations cliniques, de la positivité des réactions cutanées et, dans 2 cas, des réactions de Prausnitz-Küstner (P.K.). On a obtenu dans 3 cas une désensibilisation. La présence d'anticorps anti-insuline a été révélée par la méthode immunoautoradiographique en employant de l'insuline131J. Avant la désensibilisation la présence d'anticorps IgG a été enregistrée chez 3 patients tandis que chez 2 on a démontré également des anticorps IgA. Une réaction de P.K. positive a été observée chez des patients dont les sérums contenaient des anticorps IgA. Pendant la désensibilisation on a observé une apparition transitoire de macroglobulines capables de lier l'insuline131J. Après la désensibilisation on a constaté la persistance de la positivité aux réactions cutanées immédiates à l'insuline de porc et de boeuf. En même temps les réactions retardées et la réaction de P.K. à l'insuline de porc étaient interverties, bien que les mêmes réactions à l'insuline bovine restaient positives.
    Abstract: Resumen Cinco pacientes que padecían de alergia a la insulina han sido desensibilizados con insulina porcina según el método de Urbach y Gotlieb. El diagnóstico de alergia a la insulina ha sido puesto teniendo en cuenta las manifestaciones clínicas, el positivismo de las reacciones cutáneas, y, en 2 casos, las reacciones de Prausnitz-Küstner (P.K.). En 3 casos se ha obtenido desensibilización. La presencia de anticuerpos anti-insulina ha sido puesta en evidencia con el método inmunoautoradiográfico, empleando insulina131J. Antes de la desensibilización, la presencia de anticuerpos IgG ha sido hallada en 3 pacientes, mientras que en 2 han sido demostrados también anticuerpos IgA. Una reacción de P.K. positiva ha sido observada en pacientes cuyos sueros contenían anticuerpos IgA. Durante la desensibilización se ha observado aparición transitoria de macroglobulinas capaces de ligar la insulina131J. Al cabo de la desensibilización se ha notado la persistencia del positivismo a las respuestas cutáneas inmediatas a la insulina porcina y bovina. Al mismo tiempo, las respuestas retardadas y la reacción de P.K. a la insulina porcina cstaban invertidas, no obstante que las mismas reacciones a la insulina bovina hubieran quedado positivas.
    Notes: Riassunto Cinque pazienti con allergia all'insulina sono stati desensibilizzati con insulina suina secondo il metodo di Urbach e Gotlieb. La diagnosi di allergia all'insulina è stata posta sulla base delle manifestazioni cliniche, della positività delle reazioni cutanee e, in 2 casi, delle reazioni di Prausnitz-Küstner (P.K.). In 3 casi si è ottenuta una desensibilizzazione. La presenza di anticorpi anti-insulina è stata rivelata con il metodo immunoautoradiografico impiegando insulina131J. Prima della desensibilizzazione la presenza di anticorpi IgG è stata riscontrata in 3 pazienti mentre in 2 sono stati dimostrati anche anticorpi IgA. Una reazione di P.K. positiva è stata osservata in pazienti i cui sieri contenevano anticorpi IgA. Durante la desensibilizzazione si è osservata una comparsa transitoria di macroglobuline capaci di legare l'insulina131J. Dopo la desensibilizzazione si è riscontrata la persistenza della positività delle risposte cutanee immediate all'insulina suina e bovina. Al tempo stesso le risposte ritardate e la reazione di P.K. all'insulina suina erano invertite, sebbene le stesse reazioni all'insulina bovina rimanessero positive.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01548086
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    Electronic Resource
    Morphologische Untersuchungen an der Glandula bulbourethralis der Katze (1969)
    Springer
    Cell & tissue research 101 (1969), S. 607-620 
    Details
    ISSN: 1432-0878
    Keywords: Glandula bulbourethralis ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Parenchym der Glandula bulbourethralis der Katze besteht aus weitlumigen, gebuchteten intraglandulären Gängen, in welche kurze, englumige, zumeist unverzweigte Tubuli einmünden. Der Drüse fehlt eine äußere Organkapsel, so daß ihre peripheren Tubuli stellenweise direkt zwischen den Fasern des quergestreiften M. bulboglandularis liegen. Die Drüsentubuli und die Buchten der intraglandulären Gänge sind mit einem einschichtigen Zylinderepithel ausgekleidet, auf den Gangfalten ist das Epithel abschnittsweise mehrreihig, Die sezernierende Epitheloberfläche ist durch die Ausbildung von interzellulären Sekretkapillaren vergrößert. Breite Zwischenzellspalten (Durchmesser etwa 1,5μ), in welche schlanke interdigitierende Cytoplasmafortsätze hineinragen, erstrecken sich von der Basalmembran bis kurz unter das Tubulusbzw. Ganglumen. Die lumenseitigen Zellgrenzen tragen einige stummelförmige Mikrovilli und besitzen zerklüftete Außenkonturen, die durch glykogenreiche Cytoplasmaprojektionen bedingt sind. Alle Epithelzellen sind reich an Mitochondrien. Die supranuklearen Abschnitte der meisten Gang- und Tubuluszellen enthalten Sekretgranula, welche im Elektronenmikroskop unterschiedliche optische Dichten aufweisen können. Die Granula enthalten ein PAS-positives, neuraminsäurehaltiges epitheliales Muzin, das in einzelnen Sekretkörnchen auch eine histochemische Reaktion auf Sulfatgruppen gibt. Alle Epithelzellen reagieren sehr stark auf unspezifische Esterase und stark auf β-D-Glucuronidase, β-D-Glactosidase sowie die Enzyme des Citronensäurezyklus, der Glykolyse und der Atmungskette (NAD-ICDH, SDH, ALD, LDH, ADH, GDH, NADH-T-Red, Cyt-Ox).
    Notes: Summary The bulbourethral glands of sexually mature male cats are studied with the light and electron microscope. The parenchyma consists of spacious, sinus-like intraglandular ducts and short, narrow, mostly unbranched tubular endpieces. The gland has no complete connective tissue capsule, consequently some of the peripheral tubules are situated directly in between the fibers of the surrounding bulboglandularis muscle. The endpieces and the sinus of the intraglandular ducts are lined by a simple columnar epithelium, whereas the folds of the ducts are generally covered by a low pseudostratified epithelium. The secretory surface of the cells is increased by intercellular canaliculi which communicate with the gland lumen. These canaliculi are identified on the light microscopic level by their strong 5′-nucleotidase activity. Furthermore widened intercellular spaces (approximately 1,5 μ in diameter) filled with slender, interdigitating cytoplasmic processes extend from the basal lamina to the apical junctional complexes. The luminal cell pole exhibits some short microvilli and forms irregularly shaped, glycogen containing protrusions. Within the cytoplasm of the gland cells numerous spherical mitochondria, some dense bodies, a typical Golgi apparatus, free ribosomes and a poorly developed endoplasmic reticulum are to be observed. Secretory granules which can be grouped into three types on the basis of their electron density occur in the supranuclear regions of most of the cells. According to histochemical tests all granules contain a periodate reactive sialomucin and some of them also sulfate groups. The glandular parenchyma is site of an exceptionally strong unspecific esterase activity and is rich in β-D-glucuronidase, β-D-glactosidase, aldolase, α-glycerophosphate dehydrogenase, lactate dehydrogenase, alcohol dehydrogenase, NAD-dependent isocitrate dehydrogenase, succinate dehydrogenase and cytochrome oxydase.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00335273
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    Electronic Resource
    Mass transfer operations, Second Edition, Robert E. Treybol, Mcgraw-Hill, New Yark (1968). 717 pages. $15.75 (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 155-156 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150105
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  • 44
    Electronic Resource
    Electronic Resource
    Effects of pore diffusion in the catalytic oxidation of ethylene (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 18-24 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Effects of pore diffusion in the catalytic oxidation of ethylene on copper oxide-alumina have been studied by varying the catalyst size and maintaining constant the ratio of the tube to the pellet diameter. Hydrocarbon analysis was determined with a flame ionization detector; infrared analyzers were used to determine carbon monoxide and carbon dioxide concentrations. Other reaction products were analyzed with a gas chromatograph. Curvature of the Arrhenius plots and increase in reaction order with temperature indicated a transition region between kinetic control at lower temperatures and pore diffusion control at higher temperatures. A calculation procedure which was developed to predict the conversion considering pore diffusion effects provided satisfactorily agreement between calculated and experimental results.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150109
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  • 45
    Electronic Resource
    Electronic Resource
    On the particle size distribution function and the attrition of cracking catalysts (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 35-39 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The rate of attrition of a catalyst sample, of a single particle size, can be expressed by a simple function of initial diameter and time. The initial rate is a function of initial diameter, whereas the decrease in attrition rate of a catalyst of a given size as it ages depends only on time.The attrition equation for a single size of particles is introduced into the particle size distribution function and, through mathematical analyses, yields a relationship for the attrition of a full size-range catalyst. The form of this relationship, which includes terms for attritability and severity of attrition conditions, is verified by laboratory and commercial attrition data on two full-range catalysts. The size distribution of an attrited sample is not expressible in simple analytical form, but is readily obtained by numerical analysis.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150112
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  • 46
    Electronic Resource
    Electronic Resource
    Structuring design computations (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 94-100 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Process design computations are represented by directed graphs whose edges correspond to streams of information flow between computational units. Algorithm I-R extends existing algorithms for finding the minimal sized blocks of units between which no recycle exists. Algorithm II-R orders the sequence of unit computations within a block to minimize the number of recycle parameters. Algorithm III-R uses the concept of indexing to order computations which evade algorithm II-R. This work is directed toward the evolution of efficient programs for computer-aided process design.
    Additional Material: 17 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150122
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  • 47
    Electronic Resource
    Electronic Resource
    The effect of pressure on the permeation of gases and vapors through polyethylene. Usefulness of the corresponding states principle (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 64-73 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The permeation of carbon dioxide through polyethylene membranes has been studied at pressures up to 54.4 atm. and at temperatures above and below the critical temperature of the gas (31.0°C.). The permeability coefficient is independent of pressure at the highest experimental temperature (61.0°C.), but becomes increasingly pressure-dependent as the temperature is lowered. The principle of corresponding states can be used to correlate the solubility of both gases and vapors in polyethylene over a wide range of temperatures. This principle can also be invoked to obtain an upper limit for the penetrant pressure above which the permeability coefficient becomes pressure-dependent. The effect of pressure on the permeability, solubility, and diffusivity of gases and vapors in polyethylene is discussed in some detail.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150117
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  • 48
    Electronic Resource
    Electronic Resource
    Quantum theory of matter, Second Edition, John C. Slater, Mcgraw-Hill, New York (1968) (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 3-3 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150102
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  • 49
    Electronic Resource
    Electronic Resource
    Axial dispersion of gases in packed beds (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 146-149 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150136
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  • 50
    Electronic Resource
    Electronic Resource
    Vaporization at the base of bubbles of different shape during nucleate boiling of water (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 214-219 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Differently shaped bubbles were observed growing during nucleate boiling of water at atomspheric pressure. The surface temperature beneath the bubbles was measured simultaneously with a fast response surface thermocouple. The evaporation from the base necessary to account for the observed cooling was calculated. A comparison of the ratio of vapor volume formed at the base to the total volume of the bubble shows a dependency on bubble shape. The ratio is smallest for spherical bubbles, largest for hemispherical and intermediate for oblate bubbles.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150217
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  • 51
    Electronic Resource
    Electronic Resource
    Diffusion and solution of gases into thermally softened or molten polymers: Part II. Relation of diffusivities and solubilities with temperature pressure and structural characteristics (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 106-110 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Solubilities and diffusivities of various gases (helium, nitrogen, carbon dioxide, argon, neon, krypton, and monochlorodifluoromethane) in molten or thermally softened polymers (polyethylene, polypropylene, polyisobutylene, polystyrene, and polymethylmethacrylate) have been correlated with structural characteristics, temperature, and pressure. Temperature dependence of both Henry's Law constants and diffusivities were of the Arrhenius equation form. No appreciable effect of pressure was found for either Henry's Law constants or diffusivities up to 300 atm. Earlier correlations for Henry's Law constants in solid polymer systems were found to be inapplicable for molten and thermally softened polymers. New correlations were developed individually for the latter systems. The correlating factor used was the gas Lennard-Jones force constant. Existing correlations for diffusivities were also found not to apply to molten and thermally softened systems. New correlations were again developed on an individual polymer basis. These related diffusivity to gas Lennard-Jones collision diameter or molecular diameter. Generalized correlations were also developed that held for a number of polymers. These were for both Henry's Law constants and diffusivities.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150124
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  • 52
    Electronic Resource
    Electronic Resource
    Relationships between process equations for processes in connection with Newtonian and non-Newtonian substances (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 303-305 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150236
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  • 53
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    Electronic Resource
    Masthead (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969) 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150301
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  • 54
    Electronic Resource
    Electronic Resource
    Numerical optimization of large interconnected systems (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 276-281 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: This paper describes a numerical procedure for optimizing a large set of interconnected systems with respect to a given index of performance. The method automatically constructs the vector differential equation of the complete system from (a) the vector differential equations describing the behavior of the components of the system and (b) the manner of their interconnection. A hill-climbing method is then used to select optimum values of the system's parameters to maximize a given index of performance. An example of the procedure applied to a high order system is included.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150228
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  • 55
    Electronic Resource
    Electronic Resource
    Crystallization kinetics of pure and binary melts (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 442-449 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: An absolute rate theory based on a plausible model of the activated state, was developed for the interfacial kinetics of crystal growth from the melt. Except for liquid metals the theory predicts the growth rates of pure materials within about an order of magnitude. A microinterferometric technique was employed to observe liquid compositions near the faces of crystals growing from binary melts. For the simple eutectic system composed of salol and thymol, the theory represents the composition and temperature dependence of the growth rate.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150326
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  • 56
    Electronic Resource
    Electronic Resource
    The control of nonlinear systems VI. Computational use of nonlinear programming (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 308-311 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150239
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  • 57
    Electronic Resource
    Electronic Resource
    The laminar boundary layer on a moving continuous flat sheet immersed in a non-Newtonian fluid (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 327-333 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The laminar boundary layers on a moving continuous flat surface in non-Newtonian fluids characterized by the power law model are investigated using exact and approximate methods. Both pseudoplastic and dilatant fluids are considered. Numerical solutions of the boundary-layer equations are obtained for values of the parameter n in the power law model ranging from 0.1 to 2.0. An integral solution of the momentum equation, which can be used to obtain values of the dimensionless shearing stress that are in good agreement with the exact values, is developed. An integral solution to the energy equation is also presented.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150307
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  • 58
    Electronic Resource
    Electronic Resource
    Heat transfer from a cylinder in an air-water spray flow stream (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 357-362 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Forced convection heat transfer from vertical cylinders normal to an air-water spray flow stream was measured over an air velocity range from 60 to 140 ft./sec. and a water spray density range from 0.03 to 0.50 lb.m/(min.) (sq. in.). Local heat transfer coefficients were determined at 15 deg. intervals around the circumference of both a 1.5 and a 1.0 in. diam. cylinder. It was found that the addition of 0.426 lb.m/(min.) (sq. in.) of water spray to a 133 ft./sec. air stream raised the stagnation point heat transfer coefficient from 45 to 1,650 B.t.u./(hr.) (sq. ft.) (°F.). Similar intensification was found for other angles around the cylinder circumference; however, the magnitude decreased with increasing distance from the stagnation point. Local heat transfer coefficients were normalized with respect to their corresponding stognation point values and plotted parametrically as a function of angle and air velocity. These profiles showed that the normalized heat transfer coefficients decreased with increasing air velocity at angles other than the stagnation point. Average cylinder heat transfer coefficients were calculated from the air-water data and two correlations were obtained relating these coefficients to the air and the water spray Reynolds number.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150311
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  • 59
    Electronic Resource
    Electronic Resource
    The aqueous phase oxidation of cyclohexane using gamma radiation (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 387-392 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A study was made of the radiolytic oxidation of cyclohexane in aqueous solution by using cobalt 60 gamma radiation. In the presence of dissolved oxygen gas the reaction proceeds irreversibly with the formation of a number of oxidation products. Those identified were cyclohexanol, cyclohexanone, and hydrogen peroxide. Trace quantities of carbon dioxide were also detected in the liquid phase. Using a constant dose rate of 15 × 104 rad./hr. in all runs, radiation yields were G(C6H11OH) = 0.49, and G(C6H10O) = 1.08. When molecular oxygen was excluded from the system, neither cyclohexanol nor cyclohexanone was formed on irradiation. A simplified kinetic model based on competition by the various solutes in the system for a single primary radical species produced by radiolysis of the solvent molecules is developed. Results generated using the mathematical model are compared with the experimental data. Excellent agreement between the observed and computed trends is noted at radiation doses up to 50 × 104 rad.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150317
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  • 60
    Electronic Resource
    Electronic Resource
    Optimal control of tubular reactors. Part II. Jacketed configuration with step feed disturbance (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 414-418 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The optimal unsteady control of a jacketed tubular reactor with and without heat generation due to chemical reaction in response to a step disturbance in the feed stream concentration is computed. More rigorous control action was found to be necessary for the case with heat generation than without heat generation. Convergence of the method was also investigated with fixed and free final time.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150322
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  • 61
    Electronic Resource
    Electronic Resource
    Mutually dependent heat and mass transfer in laminar duct flow (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 434-441 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: An analysis is performed of the strongly coupled heat and mass transfer processes which result from sublimation of mass from the walls of a duct into a flowing gas, the latent heat being provided solely by convective transfer from the gas. The flow is assumed to be laminar and hydrodynamically developed. Results are given for the streamward variations of the bulk and wall temperatures and mass fractions, of the heat and mass transfer rates, and of the local heat transfer coefficient. Representative temperature and mass fraction profiles are also presented. Entrance lengths characterizing the near approach to fully developed conditions are tabulated. Comparisons are made of the present results (based on a parabolic velocity profile) with those based on a slug flow velocity profile. A subsidiary analysis using the Lévěque model is also performed and the results compared with those of the principal solution.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150325
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  • 62
    Electronic Resource
    Electronic Resource
    Base film over which roll waves propagate (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 712-715 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The liquid that moves along the duct walls in the annular regime observed in gas-liquid flows often consists of a series of flow surges (roll waves) moving over a thin liquid film (base film). At a given gas velocity there is a critical flow rate of the liquid below which roll waves are not present. Measurements of the height and wall stress are presented to support the notion that the conditions in the base film are close to those which exist at the critical liquid flow rate.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150515
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  • 63
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    Electronic Resource
    Transport of heat and mass between liquids and spherical particles in an agitated tank (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 727-733 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Data are reported for heat transfer from water to melting ice spheres and for mass transfer in the case of dissolving spheres of pivalic acid suspended in water agitated in a stirred vessel. The transport coefficients are found to depend on agitator power input but not on agitator design, in agreement with the Kolmogoroff theory. These experimental results are used with others in the literature to develop a correlation involving Nusselt and Prandtl or Schmidt numbers together with a dimensionless group involving agitation power. The correlation is essentially independent of solid-liquid density ratio in the range 0.8 to 1.25, and in this range the gravity group also appears to be unimportant.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150518
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  • 64
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    Electronic Resource
    A study of the effects of internal rib and channel geometry in rectangular channels. Part II. Heat transfer (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 592-596 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Heat transfer and pressure drop data were taken on commercial plate heat exchange equipment. Nusselt and Euler correlations were determined for each of the six commercial heat exchangers investigated. These correlations were combined to establish a single heat transfer-pressure drop relationship for any plate type of heat exchanger channel.The results of this investigation were tested by using the correlations developed in Part I of this series to predict pressure drop data for the commercial unit based on their channel geometries. These predicted pressure drops were then used with the results of this part of the series to predict and compare heat transfer data.The correlations developed in this work allow one to determine the heat transfer characteristics in a ribbed rectangular channel from the pressure drop characteristics of the channel in question.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150422
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  • 65
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    Isothermal enthalpy difference for saturated liquid mixture via isobaric Gibbs-Duhem equation (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 615-617 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150426
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  • 66
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    Some general equations for reverse osmosis process design (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 829-836 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A generalized approach to reverse osmosis process design is presented for solution-membrane-operating systems characterized by the dimensionless parameters γ, θ, and λ defined in terms of the pure water permeability constant A, solute transport parameter (DAM/Kδ), mass transfer coefficient k on the high pressure side of the membrane, and the properties of the solution. Analytical expressions are derived, in terms of dimensionless quantities, for the change of volume of solution, concentration of the bulk solution and that of the concentrated boundary solution on the high pressure side of the membrane, the change in the permeating velocity of solvent water through the membrane, solute separation, and the other related quantities, at any instance, as a function of concentration of the product solution on the atmospheric pressure side of the membrane, or time from the start of the operation for reverse osmosis systems specified by γ, θ, and λ. The equations are applicable to membranes for which (DAM/Kδ) is independent of solute concentration and feed flow rate, and for aqueous feed solutions whose molar density can be assumed constant and whose osmatic pressure is proportional to mole fraction. The equations are developed first for the case of batch-by-batch operation, and their applicability to the flow case is then indicated.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150608
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  • 67
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    The kinetics of condensation polymerization (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 861-865 
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    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The final stages of condensation polymerization are characterized by a rapid rise in molecular weight, as the condensation product is formed and diffuses out of the polymer. The process occurring is one of desorption accompanied by a chemical reaction. The penetration theory equations for a generalized condensation polymerization reaction have been solved and some solutions are presented. The penetration theory solution, obtained by finite-difference computations, is compared with an analytical solution for the special case of no diffusional resistance.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150612
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  • 68
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    Correlation of liquid slug velocity and frequency in horizontal cocurrent gas-liquid slug flow (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 933-935 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: No Abstracts.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150623
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  • 69
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    Flow properties of suspensions with high solids concentration (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 815-822 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Equations were developed for evaluating the laminar flow behavior of high-solids suspensions from the physical properties of the liquid and solid components. A technique was developed for calculating suspension flow rates as a function of pressure drop. The technique is applicable to the design of pipe lines. Flow measurements were made in pipe-line viscometers of a unique design that minimized entrance and exit effects. Experimental flow data were obtained for suspensions consisting of nickel, alumina, copper, or glass solids in sodium, xylene, or glycerine vehicles with solids concentrations of 28 to 55 vol. %. The basis for the correlation of the data was an analytical investigation of the flow behavior that considered the particle-particle interaction that takes place in a settled suspension. The correlation equations fit all systems investigated. They take into account the effects of liquid viscosity, liquid and solid densities, particle size, size distribution, particle surface area, volume fraction of solids in the suspension, and volume fraction of solids at maximum settled conditions.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150606
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    Electronic Resource
    The dynamic modeling, stability, and control of a continuous stirred tank chemical reactor (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 853-860 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A realistic CSTR model was developed and verified experimentally. The reaction studied was the exothermic, base sodium hydroxide catalyzed decomposition of hydrogen peroxide. The model was used to evaluate the usefulness of the following stability analyses: steady state analysis, local linearization and Liapunov's direct method through Krasovskii's theorem. The effect of control valve hysteresis on the system was also investigated.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150611
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  • 71
    Electronic Resource
    Electronic Resource
    Single-phase flow through porous media (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 866-872 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The local volume average of the equation of motion is taken for an incompressible fluid flowing through a porous structure under conditions such that inertial effects may be neglected. The result has two terms beyond a pressure gradient: g, the force per unit volume which a flowing fluid exerts on a porous structure, and the divergence of the local volume-averaged extra stress tensor (viscous portion of the stress tensor).Constitutive equations for g are examined with the aid of the principle of material indifference. When g is assumed to be a function of the velocity of the fluid relative to the solid as well as various scalars, the usual results for a nonoriented (isotropic) porous structure are obtained. When g is assumed to be a function of the local porosity gradient as well, we derive a new expression for g applicable to oriented (anisotropic) porous structures.For a Newtonian fluid with a constant viscosity, the divergence of the local volume-averaged extra stress tensor is proportional to the Laplacian of the averaged velocity vector. Boundary conditions for the averaged velocity vector are discussed. Three problems are solved for the flow of an incompressible Newtonian fluid in a nonoriented permeable medium. These solutions, as well as an order-of-magnitude analysis, suggest that we may often neglect both the Laplacian of average velocity and the boundary conditions for the tangential components of averaged velocity at an impermeable wall.Two specific constitutive equations for g are proposed for the flow of incompressible Noll simple fluids in nonoriented porous structures. Flow through a porous medium bounded by an impermeable cylindrical surface is solved for these two constitutive equations, and the results are compared with previously available experimental data.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150613
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  • 72
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    Thermodynamics, Second Edition, William C. Reynolds, Mcgraw-Hill, New York (1968). 496 pages. $11.50 (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 3-155 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150104
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  • 73
    Electronic Resource
    Electronic Resource
    Residence time distribution of the dispersed phase in a spray column (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 4-10 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A dye tracer technique was utilized to measure the residence time distribution of the drops in a spray column, operating with a dispersed or a dense packing of drops, for a wide range of flow rates, in a 15 cm.in diameter, 150 to 160 cm. long column proper.For dispersed packing of drops and for flow rates below the onset of coalescence, the flow of the drops was approximately plug flow, with a variance of the residence time distribution of 0.095. For flow rates above the onset of coalescence within the column, the variance increased sharply to 0.55 and decreased at higher flow rates.For dense packing of drops the variance of the residence time distribution was in the range of 0.1 to 0.5. This variance is attributed to the effect of bypassing water and kerosene near the wall of the column. A mathematical model based on this effect showed reasonable fit with the experimental results. This model predicts an approach to plug flow of the drops for large diameter columns.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150107
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  • 74
    Electronic Resource
    Electronic Resource
    Sensitivity of a class of distributed parameter control systems (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 57-63 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A sensitivity matrix is defined as a measure of trajectory deviations to small parameter variations of both open and closed loop controlled nonlinear parabolic and first-order hyperbolic systems. In general the parameters may enter through the system equations or the boundary conditions and may be time or spatially dependent. The introduction of a positive measure of the sensitivity, the norm of the sensitivity matrix, into the performance index is shown to be effective in limiting the trajectory deviations due to the parameter variations. The open and closed loop control of a double pipe heat exchanger is analyzed with the open loop problem solved by an approximate procedure. The sensitivity reformulation is successful in reducing trajectory sensitivity, however at the cost of decreased overall performance.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150116
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  • 75
    Electronic Resource
    Electronic Resource
    Axial dispersion in turbulent flow through standard 90 degree elbows (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 81-85 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Axial dispersion was studied experimentally for turbulent flow through a 1 1/4-in. piping system containing 90 deg. elbows. The Reynolds number range was 15,400 to 96,555. The imperfect pulse tracer technique was used with the axial dispersion numbers being obtained from the difference in variances of concentration-time curves observed at two points in the system.Elbows interconnected by short lengths of pipe with each succeeding one reversed so as to cause a change in the direction of flow, increased axial dispersion by 35 to 61% over that expected for straight pipe, while the same elbows turned so as to form a helix decreased the dispersion substantially; however, the amount of axial dispersion was still 8 to 22% greater than that observed for straight pipe.The equivalent lengths of the elbows depend upon both their arrangement and the Reynolds number. Closely placed, helically arranged elbows required equivalent lengths of from 2.9 to 5.1 diam., while a reversed arrangement required 6.9 to 11.6 diam. Elbows separated by a developing length and randomly arranged yielded an equivalent length range of 3.6 to 10.6 diam. The geometical l/d ratio of the elbows used was 2.05.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150119
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  • 76
    Electronic Resource
    Electronic Resource
    The estimation of parameters for a commonly used stochastic model (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 100-105 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A region into which particles arrive in a random manner, remain a random amount of time, and then leave is considered. This model is used in penetration theories of heat and mass transfer. From observations of the number of particles present at any time, it is desired to estimate arrival and exit statistics, residence time statistics, and average rates of transfer across the region. Assuming arrival is a Poisson process, equations governing the above statistics are derived. Some problems in spectral analysis arising from the use of nondifferentiable stochastic processes are solved. Estimators for important parameters are discussed, and it is shown that generally they are biased. A derivation linking the rate of transfer across the region with the rates of transfer of particles is obtained and compared with other such results.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150123
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  • 77
    Electronic Resource
    Electronic Resource
    Digital resolution of residence time distributions from pulse response data (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 126-127 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150128
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  • 78
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    Oxidation of hydrogen in a helium stream by copper oxide: Analysis of combined film and pore diffusion with rapid irreversible reaction in a fixed-bed process (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 116-123 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Differential equations were derived to describe the system characterized by a rapid, irreversible reaction of a fluid species in a flowing fluid with a fixed bed of solids in which the reaction rate was controlled by mass transfer of the reacting fluid from the bulk fluid to the reaction site in the solid. Two kinds of mass transfer resistances were assumed, external or film diffusion resistance, and internal pore diffusion resistance. The set of differential equations were solved by a finite-difference method for both the generalized case and for the specific case of reaction of hydrogen in a stream of helium with fixed beds of copper oxide pellets.The hydrogen-copper oxide reaction is one step in a proposed method for removal of hydrogen as a contaminant in the helium coolant of nuclear reactors. This reaction was experimentally investigated in tests with both differential and deep beds of copper oxide in the temperature range of 400 to 600°C., at pressures of 10.2 to 30.0 atm., with gas mass flow rates of 0.0050 to 0.050 g./sq.cm.-sec, and with inlet hydrogen concentrations of 0.0008 to 1.21 vol. %. These tests showed that the system could be described by the two rate-limiting steps: film and pore diffusion of hydrogen. Differential-bed tests were used to establish hydrogen transport properties within the porous copper oxide pellets, and tests with deep beds were used to establish external mass transport properties.Generalized breakthrough curves were determined by a computer solution of the mathematical model. These curves can be the basis for design of fixed-bed copper oxide oxidizers for gas-cooled, nuclear reactor purification systems and for design of any fixed-bed system which follows the assumed reaction mechanism.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150126
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  • 79
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    Electronic Resource
    On the height of incipience of boiling in tubes of small diameter for a liquid in laminar flow (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 133-135 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150131
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  • 80
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    Electronic Resource
    Diffusion-controlled rate mechanisms in gas-solid reaction systems (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 136-137 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150132
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  • 81
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    Electronic Resource
    Two-phase friction factor for nitrogen between one atmosphere and the critical pressure (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 144-146 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150135
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  • 82
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    Electronic Resource
    Masthead (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969) 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150201
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  • 83
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    Computer calculotions for high-pressure vapor-liquid equilibria, J. M. Prausnitz and P. L. Chueh, Prentice Hall, Inc., Englewood Cliffs, N. J. (1968). 239 pages. $12.95 (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 319-320 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150205
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  • 84
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    Electronic Resource
    Stability of high dimensional nonlinear systems using Krasovskii's theorem (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 171-177 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Liapunov's direct method is used to establish a finite region of asymptotic stability for nonlinear systems with an arbitrary number of state variables. The procedure is a geometric one in multidimensional space which uses the Fletcher-Powell minimization technique to find the maximum time derivative of the Liapunov function on the closed Liapunov hypersurface. Three detailed examples are presented, the first being the classical 2-variable CSTR with heat transfer and the third being a 32-variable 16-stage model of an adiabatic tubular reactor with axial diffusion.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150209
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  • 85
    Electronic Resource
    Electronic Resource
    Maximum temperature rise in gas-solid reactions (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 194-199 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A shell progressive kinetic model is used to determine the temperature rise in a spherical pellet for a gas-solid diffusion controlled reaction. The effects of heat and mass transfer resistances in the gas film as well as inside the pellet are investigated. The predicted temperature rise may be severe enough to cause sintering to catalyst pellets in which reactions such as combustion of coke occur.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150213
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  • 86
    Electronic Resource
    Electronic Resource
    Process dynamics of distributed parameter counterflow systems in laminar flow (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 220-226 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150218
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  • 87
    Electronic Resource
    Electronic Resource
    Transport of toluene through fully swollen polyethylene (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 208-214 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Experiments have been carried out to measure the permeation of tritium-labeled toluene through polyethylene films fully swollen with chlorobenzene, mesitylene, cumene, toluene, ethylbenzene, cyclohexane, tetrahydronaphthalene, and decahydronaphthalene. The results show characteristic Arrhenius temperature dependence over the range 25 to 40°C. The permeation of toluene through the films appears to be enhanced by increased solubility of the swelling agent (estimated from the work of others) in the film and there also appears to be a rough correlation between permeability of toluene and the boiling points and vapor pressures of the swelling agents. The range of permeabilities measured at 25°C. is 2.09 × 10-7 to 0.51 × 10-7 sq.cm./sec., the extremes of measured permeation activation energy, Ep, are 11.41 to 16.68 kcal./mole, and the pre-exponential factor, Po, falls within the interval 36.59 to 1.29 × 105 sq.cm./sec. A very definite linear relationship or compensation effect is evident between Po and Ep. Except as mentioned above, none of these quantities appears to correlate uniformly with the following properties of swelling solvent: molecular weight, dipole moment, specific gravity, vapor pressure, boiling point, heat of vaporization, critical temperature, viscosity, surface tension, molar volume, molecular area or other molecular dimensions.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150216
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  • 88
    Electronic Resource
    Electronic Resource
    Oxidation-reduction reactions in stirred liquid-liquid systems (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 245-249 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Oxidation-reduction rates have been determined in stirred liquid-liquid systems wherein tetravalent cerium ions in a continuous aqueous phase were reduced by tetrachlorohydroquinone contained in dispersed organic droplets. Kinetic data obtained (using low volume fractions (〈0.06) of dispersed organic phase) indicate that the rate of reduction of ceric cerium is proportional to the extent of the interfacial area of the stirred liquid-liquid system. Two possible rate-limiting mechanisms are discussed to explain the observed kinetic behavior.This liquid-liquid electron exchange system might find potential use as a chemical tool for measuring changes in interfacial area as influenced by various mixing parameters.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150222
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  • 89
    Electronic Resource
    Electronic Resource
    Joule-Thomson effects in gas mixtures: The nitrogen-methane-ethane system (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 256-263 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Pressure-temperature data were obtained along isenthalps for nitrogen, methane, and three ternary nitrogen-methane-ethane mixtures. These data were differentiated to obtain Joule-Thomson coefficients over the temperature range from ambient to 200°K. and at pressures from 165 atm. to about 5 atm. Data for nitrogen was obtained down to 140°K.The resulting Joule-Thomson coefficients were compared with predictions based on the Beattie-Bridgeman and Benedict-Webb-Rubin equations of state and on the virial equation of state truncated after the third virial coefficient. These comparisons show that the Benedict-Webb-Rubin equation could predict the data with a deviation averaging 1.7%. The Beattie-Bridgeman predictions were highly dependent upon the mixture rules used, with the best set of mixture rules giving an absolute average deviation of 4.8%. Predictions using the virial equation with virial constants obtained from the Lennard-Jones potential energy function using a geometric mean minimum potential energy deviated from the experimental data by 5%.In all of these comparisons, the virial coefficients of ethane appear to be in greatest uncertainty, and the predictions of mixture data high in ethane least satisfactory. Thus it appears that improved data on the pure components, particularly ethane, are vital to any satisfactory evaluation of mixture properties.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150224
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  • 90
    Electronic Resource
    Electronic Resource
    Effects of ultrasonic vibrations on heat transfer to liquids by natural convection and by boiling (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 281-288 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The effects of ultrasonic vibrations on heat transfer to water and methanol by natural convection and by boiling were measured at three ultrasonic energy levels with frequency ranging from 20.6 to 306 kcycles/sec., using electrically heated platinum wires of diameters 0.007 and 0.010 in. Up to an eight-fold increase in heat transfer coefficient was obtained in natural convection, but the effects diminished with increased temperature difference and became negligible in the well-developed nucleate boiling region. High-speed photographs showed that the increase was due to the motion of cavitation bubbles on the wire surface. The heat transfer results were correlated by local cavitation activity values measured by a technique developed for this work.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150229
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  • 91
    Electronic Resource
    Electronic Resource
    On the wave characteristics of falling films (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 301-303 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150235
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  • 92
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    Cost effectiveness - the economic evaluation of engineered systems, J. Morley English, Editor, John Wiley, New York (1968). 301 pages (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 475-476 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150303
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  • 93
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    Electronic Resource
    Laminar velocity profiles in developing flows using a laser doppler technique (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 323-327 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A laser doppler flowmeter is used to obtain velocity profiles in circular glass tubes downstream from a plug composed of brass screens. The apparatus for measuring point velocities of particles suspended in a fluid is described. Measurements were made very close to the plug at Reynolds numbers of 16.5, 47, and 274, and the flow development followed down the tube. The results show that the entrance flow development is dependent on the inlet profile shape and the Reynolds number for Reynolds numbers below 300.The flow development at Reynolds numbers less than 300 was considerably slower than that predicted by the boundary-layer solution of the equations of motion starting with a flat profile.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150306
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  • 94
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    Electronic Resource
    The change in pore size distribution from surface reactions in porous media (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 339-350 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: When a porous solid is penetrated by a reactive fluid which changes the pore geometry, the macroscopic properties of that porous material may be greatly changed. A model is proposed in which the matrix is visualized as being a number of short cylindrical pores dispersed randomly throughout the solid. The change in the distribution of these cylindrical pores is then represented by a integrodifferential equation which is solved for two special cases.The evolution of the pore size distribution is determined by the particular way in which the solid-liquid boundary takes place. The case considered here is that of a surface reaction which dissolves the solid thus continuously enlarging the pores. The rate of reaction is calculated theoretically using a laminar flow diffusion model and this growth rate expression is then taken as the basis for numerical calculations relating to the action of dilute hydrochloric acid on limestone.A comparison is made with experimental results and it is found that the model behaves in much the same way as the real system although the observed rate of pore growth was two to three times that predicted by the diffusion model. Several possible explanations for this discrepancy are being tested.An exact solution of the integrodifferential equation for highly retarded reaction rates has been found with the change in permeability being given in terms of the change in porosity. This result will permit a prediction of the stimulation that can be achieved in acidizing oil wells with retarded acids.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150309
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  • 95
    Electronic Resource
    Electronic Resource
    Newtonian jet stability: The role of air resistance (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 379-383 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The stability of high speed laminar Newtonian jets is studied as a function of ambient air pressure. For Weber numbers less than 5.3 (based on air density) air pressure has no effect on stability. Ambient viscosity, through the effect of shear stresses acting on the jet surface, gives rise to the maximum in the breakup curve. For large Weber numbers ambient pressure effects can alter, and eventually control, the appearance of the maximum.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150315
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  • 96
    Electronic Resource
    Electronic Resource
    Optimization of complex chemical plants by a gradient technique (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 393-400 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The gradient technique and Lagrange multiplier are used to obtain the optimum of complex chemical plants. The advantage of this approach is its ability to handle nearly all types of complex stages in a natural way. This approach is used to solve a heterogeneous complex chemical process with recycle. It is shown that although there are many different iteration loops, the convergence rate is fast even with rough starting values and only 0.3 minute is needed to obtain the optimum operating conditions.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150318
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  • 97
    Electronic Resource
    Electronic Resource
    Optimal control of tubular reactors. Part I. Computational considerations (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 410-414 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The necessary conditions for optimization of a system governed by a nonlinear vector first-order partial differential equation with two (space and time) independent variables, such as governs the unsteady behavior of tubular flow reactors, are derived. Rather general objective functionals and boundary conditions, such as the recycle of unconverted reactant with an appropriate time delay for separation and a free choice of final time, are allowed. A gradient technique in control space is formulated, and it is shown that distinct computational advantages can accrue from the use of the method of characteristics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150321
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  • 98
    Electronic Resource
    Electronic Resource
    Turbulence phenomena in drag reducing systems (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 426-434 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: An analysis based on the Townsend-Bakewell model of the eddies in the wall regions of turbulent shear flows shows that viscoelastic fluid properties must lead to significant reductions in the rate of production of turbulent energy. This analysis in turn leads to the proper form of the similarity laws for drag reducing fluids, heretofore deduced empirically.Measurements of the axial and radial turbulence intensities for flow through smooth round tubes are reported, as are measurements of the time-averaged velocity profiles and the drag coefficients. These indicate that for solutions exhibiting drag reduction at all Reynolds numbers the flow may be transitional to Reynolds numbers of the order of 105. This transitional flow consists of alternating patches of laminar and turbulent fluid, within each of which the flow characteristics are approximately similar to those of Newtonian fluids. At high Reynolds number conditions with the turbulent field fully developed the velocity profile in the core is flatter under drag-reducing conditions than for turbulent Newtonian fluids, a change dependent on the increased isotropy of the turbulent field of the drag-reducing fluid. These effects appear to be a result of increases in the time scales of the radial fluctuations caused by the fluid properties.Design calculations based upon the present results suggest that in large diameter pipelines, or in boundary layers on large objects, drag reduction may not be attainable under conditions of practical interest until fluids having relaxation times an order of magnitude larger than those presently available, but with comparable viscosity levels, are developed or, alternately, until fluids exhibiting Weissenberg numbers which do not change with deformation rate, can be found.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150324
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  • 99
    Electronic Resource
    Electronic Resource
    Clapeyron equation of a multicomponent solution (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 460-460 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150329
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  • 100
    Electronic Resource
    Electronic Resource
    Chemical engineering, Volume 2, Second Edition, J. M. Coulson and J. F. Richardson, Pergamon Press, Oxford (1968). 790 pages. $9.50 (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 482-636 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150402
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