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  • 1
    Electronic Resource
    Electronic Resource
    Factors affecting food consumption and growth of walleye, Stizostedion vitreum, larvae in culture ponds (1999)
    Springer
    Hydrobiologia 400 (1999), S. 129-140 
    Details
    ISSN: 1573-5117
    Keywords: fish ; energetics ; temperature ; feeding ; prey abundance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract I examined food consumption and growth of walleye larvae in extensive culture ponds using direct methods and a bioenergetics model, and compared my results with laboratory feeding and growth studies. Walleye showed a diel pattern of increasing gut fullness during daylight hours. Larvae exhibited lower maximum food consumption rates in the ponds than predicted from previous short-term laboratory feeding studies. Direct estimates and bioenergetics model estimates of daily food consumption in the culture ponds were in poor agreement and the discrepancy varied with respect to walleye size. Food consumption rates in the ponds were related to walleye size (direct estimates) or water temperature (bioenergetics model estimates) but not zooplankton abundance. Growth exceeded 0.10 g g−1 d−1 for all but one sampling interval and the maximum growth rate in the culture pond fish was double the maximum growth rate determined in the laboratory. Growth was positively related to pond temperature and negatively related to walleye mass, but was not significantly related to zooplankton abundance. Gross conversion efficiency was negatively related to walleye mass, positively related to zooplankton abundance and not related to temperature. Food consumption and growth of walleye larvae in the field may be food-limited at much lower prey abundances than previous laboratory research has suggested.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1003755115000
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  • 2
    Electronic Resource
    Electronic Resource
    Normothermic Cardiopulmonary Bypass Increases Heparin Requirements Necessary to Maintain Anticoagulation (1998)
    Springer
    Journal of clinical monitoring and computing 14 (1998), S. 323-327 
    Details
    ISSN: 1573-2614
    Keywords: heparin ; anticoagulation ; cardiopulmonary bypass ; temperature ; normothermia ; hypothermia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Medicine
    Notes: Abstract Objective. With the practice of warm cardiopulmonary bypass (CPB) at our institution we have observed an apparent increase in heparin requirements. CPB temperature predictability affects pharmacokinetics and differences in drug metabolism can be expected. We hypothesized that heparin requirements would increase with increasing CPB temperature. Methods. Following Institutional Review Board approval, we reviewed the charts of 354 patients undergoing primary coronary artery bypass graft surgery. We recorded patient demographic data, CPB duration, heparin requirements, and temperature during CPB. CPB was conducted between 24 °C and 37 °C. The Spearman's correlation coefficient, Pearson chi-square, and rank-sum tests were used for data analysis. Results. Core temperature during CPB correlated with heparin requirements (r = 0.13, p 〈 0.02). However, CPB duration was shorter in warm patients than in cold patients (r = −0.455, p 〈 0.0001). Additional heparin requirements adjusted for duration of CPB (units/minute) were also significantly greater in the warm group (p = 0.018). Conclusions. Maintenance of adequate heparin anticoagulation during CPB is clinically important. Warm CPB patients required more heparin per minute than those undergoing cold CPB. More frequent assessment of anticoagulation and administration of additional heparin should be considered in patients undergoing warm CPB.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009987505590
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  • 3
    Electronic Resource
    Electronic Resource
    Factors affecting food consumption and growth of walleye, Stizostedion vitreum, larvae in culture ponds (1999)
    Springer
    Hydrobiologia 400 (1999), S. 129-140 
    Details
    ISSN: 1573-5117
    Keywords: fish ; energetics ; temperature ; feeding ; prey abundance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract I examined food consumption and growth of walleye larvae in extensive culture ponds using direct methods and a bioenergetics model, and compared my results with laboratory feeding and growth studies. Walleye showed a diel pattern of increasing gut fullness during daylight hours. Larvae exhibited lower maximum food consumption rates in the ponds than predicted from previous short-term laboratory feeding studies. Direct estimates and bioenergetics model estimates of daily food consumption in the culture ponds were in poor agreement and the discrepancy varied with respect to walleye size. Food consumption rates in the ponds were related to walleye size (direct estimates) or water temperature (bioenergetics model estimates) but not zooplankton abundance. Growth exceeded 0.10 g g−1 d−1 for all but one sampling interval and the maximum growth rate in the culture pond fish was double the maximum growth rate determined in the laboratory. Growth was positively related to pond temperature and negatively related to walleye mass, but was not significantly related to zooplankton abundance. Gross conversion efficiency was negatively related to walleye mass, positively related to zooplankton abundance and not related to temperature. Food consumption and growth of walleye larvae in the field may be food-limited at much lower prey abundances than previous laboratory research has suggested.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1003755115000
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  • 4
    Electronic Resource
    Electronic Resource
    Conformational preferences of substituted cyclopentadienyl and heterocyclopentadienyl complexes (1978)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 111 (1978), S. 1578-1590 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Über die konformative Präferenz in substituierten Cyclopentadienyl- und Heterocyclopentadienyl-KomplexenMO-Berechnungen ergeben erhebliche Barrieren für die internen Rotationen in Thiadiborolen-Fe(CO)3- und Diazaborolen-Cr(CO)3-Komplexen. Die Gleichgewichtsgeometrien der zwei Moleküle sollten verschieden sein. Eine MO-Fragmentanalyse erklärt diese Ergebnisse und führt darüberhinaus zu einer ganz allgemeinen Analyse der Rotationsbarrieren in Heterocyclopentadienyl- und substituierten Cyclopentadienyl-ML3- und -ML2-Komplexen. Für letztere wird ein gleitender Übergang von η5- nach η2-Koordination vorhergesagt.
    Notes: Molecular orbital calculations indicate substantial barriers to internal rotation in thiadiborolene-Fe(CO)3 and diazaborolene-Cr(CO)3 complexes. The equilibrium geometry of the two molecules should also differ. A fragment analysis explains these results and leads to a general analysis of rotational barriers in heterocyclopentadienyl and substituted cyclopentadienyl-ML3 and -ML2 complexes. In the latter an interesting “slipping” from η5 toward η2 coordination is predicted.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19781110439
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  • 5
    Electronic Resource
    Electronic Resource
    Cycloheptatriene and fulvene Cr(CO)3 complexes (1978)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 111 (1978), S. 1591-1602 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloheptatrien- und Fulven-Cr(CO)3-KomplexeIm Tricarbonylchrom(0)-Komplex von 1,6-Methano[10]annulen und in einigen verwandten Komplexen nimmt die Cr(CO)3-Einheit verglichen mit allen anderen Hexatrien-Cr(CO)3-Systemen eine anomale Orientierung relativ zum Polyen ein. Eine theoretische Analyse dieses Problems zeigt, daß diese Vorzugskonformation eng mit der Cycloheptatrien-Norcaradien-Valenztautomerie zusammenhängt. Mögliche Wege, die Rotationsbarriere in derartigen Komplexen zu beeinflussen, werden aufgezeigt. Vorzugskonformation, Rotationsbarriere und Abknicken der exocyclischen Methylengruppe in Tricarbonyl(η6-fulven)chrom(0) werden diskutiert und die Analyse wird auf die analogen Benzyl-Cr(CO)3- und Cyclobutadiencarbinyl-Fe(CO)3-Kationen ausgedehnt. Die Konformation dieser Komplexe wird solchen gegenübergestellt, die zwei Elektronen mehr enthalten.
    Notes: 1,6-Methano[10]annulene-Cr(CO)3 and several related complexes adopt an anomalous orientation of the Cr(CO)3 unit with respect to the polyene, compared to all other hexatriene-Cr(CO)3 complexes. A theoretical analysis of this problem shows that these conformational preferences are closely related to the cycloheptatriene-norcaradiene valence tautomerism. Several strategies for influencing the barrier to internal rotation in these complexes are presented. An analysis of the conformational preference, rotational barrier, and bending of the exocyclic methylene group in fulvene-Cr(CO)3 is also discussed. This is extended to the analogous benzyl-Cr(CO)3 and cyclobutadiene-carbinyl-Fe(CO)3 cations. Finally, the orientations of these complexes are contrasted to those containing two more electrons.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19781110440
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  • 6
    Electronic Resource
    Electronic Resource
    Metal complexes with macrocyclic ligands. XIIIPart XII, see [1].. The complexation of Cu2+ with triazacycloalkanesHerrn Prof. Dr. E. Giovannini zum 70. Geburtstag gewidmet (1979)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 62 (1979), S. 1089-1096 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The potentiometric study of the complexation of Cu2+ with 1,4,7-triazacyclononane (1), 1,4,8-triazacyclodecane (2) 1,5,9-triazacyclododecane (3) has shown that CuL, CuL2 and (CuLOH)2 are the main species present in solution. Their stabilities (Table 1) and their absorption spectra (Table 2) indicate facial coordination of the cyclic triamines in a distorted octahedral geometry.The formation and dissociation kinetics have been measured by stopped-flow techniques. The formation in acetate buffer can be described by the reaction of Cu2+ and CuAcO+ with the monoprotonated species of the ligand. The bimolecular rate constants for these complexations (Table 3) decrease when the ring size increases. In contrast the dissociation induced by acid is only little affected by the ring size. Thus for these complexes the rate of formation and not that of the dissociation determines the overall stability.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19790620417
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  • 7
    Electronic Resource
    Electronic Resource
    Metal Complexes with Macrocyclic Ligands. IXFor part VIII see [1].. Synthesis and properties of a new class of branched N4-macrocycles with an additional ligating group in the side chain (1978)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 61 (1978), S. 1376-1387 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In the presence of Ni2+ the template reaction between 2,6-diacetylpyridine and 4-(2-dimethylaminoethyl)- or 4-(2-hydroxyethyl)-1, 7-diamino-4-azaheptane yields the complexes of either the open-chain ligand (3 and 11) or of the macrocycle (4 and 12). Reduction of the imino group in 4 and 12 with PtO2/H2 gives 5 and 13, respectively. In the case of the dimethylamino derivative 5 a mixture of at least four isomers was obtained. These were partially separated by chromatography on Sephadex SP-25 cation exchanger. Through demetalation of the Ni2+ complexes by cyanide the new macrocycles 7 and 14 were isolated, from which the corresponding Zn2+ and Cu2+ complexes were prepared.The macrocyclic Ni2+-complexes 4, 12, 5 and 13 can exist in two forms depending on the pH of the solution. At low pH protonation of the dimethylamino or hydroxy group in the side chain occurs. The metal ion is then bound to the four nitrogen atoms of the macrocycle in a square planar ligand field. At higher pH, however, the dimethylamino or hydroxy group (the last one also in its deprotonated form) can coordinate to one of the axial positions, whereby pseudooctahedral coordination geometry is induced. This reaction can be quantitatively described by a reversible acid-base equilibrium, the pKH of which greatly depends on the nature of the functional group, the degree of unsaturation of the macrocycle and the metal ion.The acid-base reaction and the concomitant structural change are a direct consequence of the unique combination of the rigid and kinetically stable structure of the macrocycle and of the flexible and kinetically labile functional group of the side chain.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19780610421
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  • 8
    Electronic Resource
    Electronic Resource
    Metal Complexes with Macrocyclic Ligands. Part XLIVPart XLIII:[1] Kinetics of the Cu2+ incorporation into a macrocyclic ligand conjugated to proteins: Model studies for the d‘post-labeling’ technique (1997)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 934-947 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the Cu2+ complexation by macrocycles 1 (4-[(l,4,8,11-tetraazacyclotetradec-1-yl)methyl]-benzoic acid) and 2 (N-propyl-4-[(1,4,8,11-tetraazacyclotetradec-1-yl)methyl]-benzamide) as well as by macrocycle 1 conjugated to bovine serum albumin (bsa) and to ribonuclease A (rnase) were studied by stopped flow techniques. For 1 and 2, the kinetics were followed in the mM range monitoring the d-d* absorption band of the Cu2+ complex. From the pH dependence of kobs, the rate law is v = [Cu2+] (kLH[LH] + kLH2[LH2]), where kLH and kLK2 are the bimolecular rate constants for Cu2+ with the diprotonated (LH2) and monoprotonated (LH1) form of the ligand, respectively. The values are kLH2 = 1.7(1) M-1s-1 and kLH = 2.3(1) 105 M-1s-1 for 1, and kLH2, = 0.28(9) M-1s-1 and kLH = 2.0(1) 105 M-1s-1 for 2. The kinetics of the Cu2+ incorporation into 1,2 and 1 conjugated to bsa and rnase, i.e., 3 and 4, respectively, were also followed using nitroso-R salt as a metal indicator in the μM range, i.e., under conditions typical for the ‘post-labeling’ technique to give radiolabeled monoclonal antibodies. In these cases, the reaction takes place between the 1:1 complex of Cu2+ with nitroso-R-salt and the macrocycle. At pH 6.5, the rates are very similar to each other indicating that the complexation properties of the macrocycle attached to a protein are not very different from those of the free ligand under comparable conditions.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19970800325
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  • 9
    Electronic Resource
    Electronic Resource
    Metal Complexes with Macrocyclic Ligands. Part XXXVIIIPart XXXVII: [1].. Steric effects in the copper(II) and nickel(II) complexes with tetra-N-alkylated 1,4,8,11-tetraazacyclotetradecanes (1995)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 78 (1995), S. 505-513 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of tetra-N-alkylated 1,4,8,11-tetraazacyclotetradecanes have been synthesized and their complexation potential towards Ni2+ and Cu2+ studied. In the case of sterically demanding alkyl substituents, such as i-Pr, PhCH2, or 2-MeC6H4CH2, no metal complexes are formed, whereas for substituents such as Me, Et, and Pr, the metal ion is incorporated into the macrocycle. The spectroscopic properties of the Ni2+ and Cu2+ complexes in aqueous solution indicate that, depending on the sterical hindrance of the N-substituents, the complexes are either square planar or pentacoordinated. All these Ni2+ and Cu2+ complexes react with N3- to give ternary species, the stability of which have been determined by spectrophotometric titrations. The tendency to bind N3- decreases with increasing steric hindrance of the alkyl substituents. The X-ray studies of the Ni2+ complex with the macrocycle 11, substituted by two Me and two Pr groups, and that of the Cu2+ complex with the tetraethyl derivative 8 show that in the solid state, the metal ions exhibit square planar coordination with a small distortion towards tetrahedral geometry.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19950780220
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  • 10
    Electronic Resource
    Electronic Resource
    Metal Complexes with Macrocyclic Ligands. Part XLIIIPart XLII [1]. Tetraazamacrocyclic nickel(II) and copper(II) complexes with aliphatic methylthio- and methoxy-substituted pendant chains (1997)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 241-252 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The 14-membered tetraazamacrocyclic Ni2+ and Cu2+ complexes of 4 (1, 4, 8-trimethyl-11-[(2-methylthio)ethyl]-1, 4, 8, 11-tetraazacyclotetradecane), 5. (1, 4-dimethyl-8, 11-bis[2-(methylthio)ethyl]-l, 4, 8, 11-tetraazacyclotetradecane), and 7 (1, 4, 8, ll-tetrakis[2-(methylthio)ethyl]-1, 4, 8, 11-tetraazacyclotetradecane), with pne, two, and four methylthio-substituted pendant chains, respectively, and the Ni2+ complex of 6 (1, 4-dimethyl-8, 11-bis (2-methoxyethyl)-1, 4, 8, 11-tetraazacyclotetradecane), with two methoxy-substituted pendant chains, were synthesized and their chemistry studied with regard to modelling F430. Solution spectra in H2O, MeCN, and DMF indicate participation of the side chain in metal coordination when the donor group is a thioether, whereas no coordination with the metal ion is observed with the ether group. Similarly the X-ray structures of the thioether-containing compounds [Ni(5)](ClO4)2, [Cu(5)](ClO4)2, and [Cu(7)](ClO4)2 show a coordination number of 5, whereas that of [Ni(6)](ClO4)2 with ether pendant chains, shows a coordination number of 4. Cyclic voltammetry of these complexes in MeCN reveals that Ni2+ is reversibly reduced to Ni+ between -0.64 and -0.77 V vs. SCE, the potential being influenced by the nature and number of the pendant chains. At more negative potentials, the thioether is cleaved, whereby a thiol is formed; the thiol is then oxidized at ca. + 0.8 V vs. SCE, when a glassy carbon electrode is used, or at ca. 0 V vs. SCE at a dropping Hg electrode. No cleavage of the ether bond in [Ni(6)](ClO4)2 is observed under similar conditions.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19970800122
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