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  • 21
    Electronic Resource
    Electronic Resource
    Springer
    Mineralogy and petrology 52 (1995), S. 61-73 
    ISSN: 1438-1168
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Description / Table of Contents: Zusammenfassung Die AI(Nb, Ta)Ti−2 Substitution im Titanit: Auftauchen einer neuen Mineralspecies? Die höchsten (Nb, Ta) Gehalte, die jemals für Titanit gefunden wurden, werden für den Maršíkov II Pegmatit in Nordmähren, Tschechei, berichtet. Der Intrusivgang ist Teil eines Amphibolit-faziell überprägten Pegmatitschwarms vom Beryll-Columbit Subtypus Der Pegmatit führt u.a. seltene tantalbetonte Rutile verwachsen mit titanbetontem Ixiolith, titanbetontem Columbit-Tantalit, Fersmit and Mikrolith. Deformationsbedingte Frakturen in den (Nb, Ta) Oxiden sind mit Titanit, als Folge der Reaktion der metamorphen Porenlösungen mit den Oxidmineralen, verkittet. Titanit zeigt begrenzte Substitutionen Na(Ta 〉 Nb)(CaTi)−1,(Ta 〉 Nb)4□Ti−4Si−1 and Al(OH, F)(TiO)−1, aber extensive (und gelegentlich einzig bedeutsame) Substitution (Al 〉〉 Fe3+)(Ta 〉 Nb)Ti−2, die eine weitverbreitete, oszillierende Zonierung hervorruft. Diese Substitution verringert den Anteil der Titanit-Komponentesensu stricto, CaTiSiO,O, auf weniger als 50 Mol% in vielen Analysen. Die Extremzusammensetzung entspricht Ca0.994Na0.11) (T10.436Sn0.007Al0.280Fe3+ 0.006Ta0.199Nb0.079)Si0.988O4(O0.974F0.026). Das AusmaB dieser Substitution ist unzureichend, um eine neue Mineralspecies zu definieren.
    Notes: Summary The highest (Nb, Ta) content ever encountered in titanite is reported from the Maršíkov 11 pegmatite in northern Moravia, Czech Republic. This dike is a member of a pegmatite swarm of the beryl-columbite subtype, metamorphosed under conditions of the amphibolite facies. The pegmatite carries, i.a., rare tantalian rutile intergrown with titanian ixiolite, titanian columbite-tantalite, fersmite and microlite. Fissures generated in the Nb, Ta oxide minerals during deformation are filled with titanite, formed by reaction of the oxide minerals with metamorphic pore fluids. The titanite displays limited degrees of substitutions Na(Ta 〉 Nb)(CaTi)−1, (Ta 〉 Nb)4□Ti−4Si−1 and AI(OH, F)(TiO)−1, but an extensive (and occasionally the sole significant) substitution (Al 〉 Fe3+)(Ta 〉 Nb)Ti−2, responsible for widespread oscillatory zoning. This substitution reduces the proportion of the titanite componentsensu stricto, CaTiSiO4,O, to less than 50 mole % in many analyzed spots. The extreme composition corresponds to (Ca0.994Na0.011)(Ti0.436Sn0.007Al0.280Fe3+ 0.006Ta0.199Nb0.079)Si0.988O4(O0.974F0.026). However, so far this substitution fails to generate compositions that would define a new species.
    Type of Medium: Electronic Resource
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  • 22
    ISSN: 1438-1168
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Description / Table of Contents: Zusammenfassung In 11 bis 60 Proben von Biotit, Muskovit und Lepidolith aus den Pegmatiten von Rožná (Typlokalität des Lepidoliths; 323 ± 9 Ma) in Westmähren wurden Chemie, Struktur-parameter, Polytypie, optische Eigenschaften und Rb-Sr-Isotopie untersucht. An beiden Lokalitäten wird früher Biotit an Endokontakten nach Innen von Muskovit und Lepidolith gefolgt, letzterer ist in und um den Kern konzentriert. In Rožná folgt 1M-Lepidolith auf 2M1-Muskovit, aber alle späteren Lepidolithgenerationen sind 2M2, nahe Tri50Ply50 und zum Teil mit 2M1-Muskovit vergesellschaftet. In Dobrá Voda sind alle Lepidolithe vom Typ 1M und frei von Muskovit, die späten Varietäten kommen Tri50Ply50 nahe. An beiden Lokalitäten ist während des Fortschreitens der Glimmerkristallisation eine Tendenz von steigendem μHF angezeigt, die in der Ausfällung von Topas ihren Höhepunkt findet. Die Polytypie des Lepidoliths kann nicht mit irgendeiner Eigenheit der Zusammensetzung oder des Wachstums korreliert worden, auch nicht mit einer Kombination von diesen. Während der ganzen Glimmerkristallisation nimmt Rb/Cs ab, aber die Tendenz von K/Rb ändert sich nach anfänglichem Abfall. Das Bor verteilt sich bevorzugt auf den Muskovit (bis zu 1.10 Gew. -% B2O3), aber die Be-, Zn-, Mn- und Sc-Gehalte sind im Lepidolith erhöht. Ein leichter Ansteig von Fe, Ba und Cl in der letzten Lepidolithgeneration könnte vielleicht durch eine Mischung von pegmatitischen Restlösungen mit metamorphen Porenlösungen verursacht sein.
    Notes: Summary The chemistry, structural parameters, polytypism, optical properties and Rb-Sr isotopes were examined in 11 to 60 samples of biotite, muscovite and lepidolite from the pegmatites at Rožná (the type locality of lepidolite; 323 ± 4Ma) and Dobrá Voda (306 ± 9Ma) in western Moravia. At both localities, early endocontact biotite is followed inwards by muscovite and lepidolite, which is concentrated in and around the core. At Rožná, a 1M lepidolite follows after 2M1 muscovite but all later generations of lepidolite are 2M2, close to Tri50 Ply50 and in part associated with muscovite 2M1. At Dobrá Voda, all lepidolite types are 1M and free of muscovite, and the late varieties approximate Tri30 Ply70. At both localities, a trend of increasing μHF is indicated during the progress of mica crystallization, culminating in precipitation of topaz. Polytypism of lepidolite is not correlatable with any compositional or growth feature, or their combination. Throughout the mica crystallization, Rb/Cs decreases but K/Rb becomes reversed after an initial decrease. Boron is partitioned preferentially into muscovite (up to 1.10 wt.% B2O3) but Be, Zn, Mn and Sc are enhanced in lepidolite. A slight increase in Fe, Ba and Cl in the last generation of lepidolite might be possibly due to mixing of residual pegmatite fluids with metamorphic pore solutions.
    Type of Medium: Electronic Resource
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  • 23
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 7 (1964), S. 115-119 
    ISSN: 1570-7458
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Die Kohlfliege, Hylemyia brassicae (Bouché), wurde vom Ei bis zur Imago auf keimfreiem Kohlrüben-Gewebe gezogen. Insgesamt verpuppten sich 17 aseptische Larven; und die 6 Männchen und 7 Weibchen, die später daraus schlüpften, waren ebenfalls bakterienfrei. Die Larven entwickelten sich nicht auf hitzesterilisiertem Gewebe, oder wenn dieses Gewebe mit fäulniserregenden Bakterien versetzt wurde. Ein Vergleich der Larvalentwicklung auf aseptischen Kohlrüben-Stücken, die mit verschiedenen Arten fäulniserregender Bakterien infiziert waren, zeigt, daß sich die Larven am besten entwickelten, wenn keine Bakterien anwesend waren oder wenn das Kohlrüben-Gewebe nur langsam faulte. Es kamen weniger Larven zur Verpuppung, und die Puparien waren am kleinsten, wenn die Larven mit Kohlrüben-Gewebe ernährt wurden, das infolge Befalls mit Erwinia atroseptica (van Hall) Jennison oder Erwinia carotovora (Jones) Holland rasch faulte. Die Verpuppungs-Prozentsätze der Larven nach Fütterung mit Kohlrüben-Stücken, die mit E. atroseptica, E. carotovora, einer unbekannten Erwinia-Art (die eine langsame Fäulnis verursacht) oder einem Gemisch von E. atroseptica und der Erwinia-Art infiziert waren, sowie in der Kontrolle (ohne Bakterien), betrugen 28, 55, 70, 81, und 75%. Eine unbekannte Erwinia-Art, die durchgängig von verschiedenen Entwicklungsstadien der Kohlfliege von Kohlrüben-Feldern isoliert werden konnte, hemmte die von E. atroseptica ausgelösten Fäulnisprozesse, wenn ein Gemisch der beiden Bakterien in Kohlrüben-Gewebestücke gebracht wurde. Dies vermag zum Teil das geringe Auftreten der Weichfäule auf Kohlrüben-Feldern zu erklären, die von Kohlfliegen befallen sind.
    Notes: Abstract The cabbage maggot, Hylemyia brassicae (Bouché) was reared from egg to adult under aseptic conditions on rutabaga (Swede; Brassica napus napobrassica). No larvae survived either on contaminated or uncontaminated rutabaga plugs sterilized by heat. A comparison of larval development on rutabaga inoculated with several species of decay-producing bacteria showed that larvae developed best on healthy uncontaminated rutabaga tissue or on rutabaga tissue that decayed slowly. Survival was lowest and puparia were smallest when larvae fed on plugs that were decayed rapidly by virulent soft-rot bacteria.
    Type of Medium: Electronic Resource
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  • 24
    Electronic Resource
    Electronic Resource
    Springer
    Bulletin of environmental contamination and toxicology 26 (1981), S. 513-519 
    ISSN: 1432-0800
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
    Type of Medium: Electronic Resource
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  • 25
    Electronic Resource
    Electronic Resource
    Springer
    Journal of comparative physiology 183 (1998), S. 69-76 
    ISSN: 1432-1351
    Keywords: Key words Phenotypic plasticity ; Chemoreceptors ; Antenna ; Grasshopper ; Salicin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Grasshoppers, Schistocerca americana, reared from hatching on artificial diet had fewer sensilla on the antennae in the final larval stage than insects reared on lettuce. This was true of basiconic and coeloconic sensilla (presumed olfactory) and trichoid sensilla (presumed gustatory). The degree of difference varied along the antenna and with sensillum type. Adding salicin to the diet restored the numbers of all types of sensillum to levels equal to, or approaching, those in lettuce-fed insects. The addition of some volatile compounds – carvone (monoterpene), chalcone (flavonoid), citral (monoterpene) and guaiacol (phenolic) – resulted in slight increases in number, but coumarin (phenylpropanoid) had no effect. None of the compounds, either singly or in combination, produced more sensilla than were present in plant-fed insects.
    Type of Medium: Electronic Resource
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  • 26
    ISSN: 1437-1596
    Keywords: Cranio-facial identification ; Facial reconstruction ; 3D Computer graphics ; Video superimposition ; Laser scanner
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Law
    Notes: Abstract A facial image was reconstructed from the skull, part of a complete skeleton found in woodland, of a male person who had hanged himself from a tree. In addition, video superimposition was carried out with antemortem photographs of a person suspected of being the victim, and a good match was obtained. In a further case, a cheaper video-transparency superimposition was carried out, with identity later being confirmed on the basis of dental records. The techniques and the problems encountered are discussed. According to our experience, 3D computer reconstruction and video superimposition have a useful role in the process of identification, particularly in the early stages of an investigation and when other more definitive methods may not be available.
    Type of Medium: Electronic Resource
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  • 27
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 199 (1963), S. 701-702 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] When the 'node' is stimulated by direct current there is a repetitive response. Before the first action potential a normal local potential develops, but the following action potentials arise at a level of depolarization greater than the amplitude of the first local potential. Therefore no pacemaker ...
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  • 28
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 203 (1964), S. 872-873 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Fig. 1. Tracings from original records illustrating the modification of the form of the action potential when anodal current (dashed line), and cathodal current (solid line) are applied during the repolarization phase. The normal course of repolarization is shown by the fine solid line. Action ...
    Type of Medium: Electronic Resource
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  • 29
    ISSN: 1420-908X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 30
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract To determine the origin of juvenile loggerhead turtles (Caretta caretta) that occupy the Charleston Harbor Entrance Channel at Charleston, South Carolina, USA, mitochondrial DNA restriction-fragment length polymorphisms from this feeding population were compared to haplotypes from candidate nesting populations. Previous studies have defined two major nesting populations in the southeastern USA, one corresponding to Florida and the other to Georgia/South Carolina. These nesting populations are distinguished by both unique haplotypes and frequency distributions of common haplotypes. The frequency distribution of haplotypes in the juvenile feeding-ground population was significantly different from both nesting populations, implying that the feeding aggregate is drawn from two or more nesting populations. Assuming that these turtles are derived exclusively from rookeries in the southeastern USA, a maximum likelihood estimator indicates that approximately half are from the Florida rookery and half are from the northern (Georgia/South Carolina) rookery complex. Because 91% of nesting in the southeastern USA occurs in Florida rookeries and 8% in the northern complex, the 50:50 ratio indicates that juvenile turtles from Georgia and South Carolina tend to feed preferentially near their respective rookery locations. Human encroachment on this feeding habitat may pose an especially high risk to the smaller Georgia/South Carolina rookeries.
    Type of Medium: Electronic Resource
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