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Berlin Brandenburg

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  • Kaiser, Kle  (45)
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  • 1
    Article
    Article
    Language: English
    In: Environmental health perspectives, February 2004, Vol.112(2), pp.A86; author reply A86-7
    Keywords: Environmental Exposure ; Models, Chemical
    ISSN: 0091-6765
    E-ISSN: 15529924
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  • 2
    In: Canadian Journal of Fisheries and Aquatic Sciences, 1982, Vol.39(4), pp.571-579
    Description: A detailed statistical evaluation of the levels of organochlorine contaminants in sea lamprey ( Petromyzon marinus ) and simultaneously caught lake whitefish ( Coregonus clupeaformis ) from the northern parts of Lakes Huron and Michigan is described. The analysis of residue ratios, both within each species and between, allows an immediate recognition of rising and falling trends of contamination with a high degree of confidence. This improvement over the conventional method of monitoring one species over several years is accomplished with comparatively little effort in sampling and chemical contaminant analysis. The described technique exploits the unique biological relationship of the lamprey and its host and is also based on the significantly shorter lifespan of the (adult) lamprey compared to that of the host. Rising trends in PCB and DDE contamination and declining trends for the levels of DDT, dieldrin, endrin, chlordane, hexachlorobenzene, heptachlorepoxide, and -hexachlorocyclohexane were observed in 1978, the year of collection. Key words : organochlorine, contamination, trend, ratio, Petromyzon marinus , Coregonus clupeaformis
    Description: On trouvera dans l'article qui suit la description d'une valuation statistique dtaille des niveaux de contaminants organochors chez la grande lamproie marine ( Petromyzon marinus ) et le grand corgone ( Coregonus clupeaformis ) capturs en mme temps dans les secteurs nord des lacs Huron et Michigan. L'analyse des rapports de rsidus, tant au sein de chaque espce qu'entre les espces, permet de reconnatre immdiatement, avec un haut degr de confiance, les tendances, la hausse ou la baisse, de la contamination. Cette amlioration sur la mthode conventionnelle de surveillance continue d'une espce pendant plusieurs annes est le fruit d'un chantillonnage et d'une analyse chimique des contaminants ncessitant relativement peu d'effort. La mthode met profit la relation biologique unique entre la lamproie et son hte et se base, en outre, sur la dure de vie de la lamproie (adulte), nettement plus courte que celle de l'hte. Nous avons observ en 1978, l'anne de collection, une tendance la hausse de la contamination par BPC et DDE, et la baisse des niveaux de DDT, diedrine, endrine, chlordane, hexachlorobenzne, heptachlorpoxyde et -hexachlorocyclohexane.
    Keywords: Pollution Monitoring ; Environmental Impact ; Marine Pollution ; Pesticides ; Bioaccumulation ; Pollution Monitoring ; Environmental Impact ; Marine Pollution ; Pesticides ; Bioaccumulation ; Coregonus Clupeaformis ; Petromyzon Marinus ; North America ; North America, Great Lakes ; Pollution - Organisms/Ecology/Toxicology ; Pollution Effects ; Other Aquatic Communities ; Great Lakes;
    ISSN: 0706-652X
    E-ISSN: 1205-7533
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  • 3
    In: Canadian Journal of Fisheries and Aquatic Sciences, 1980, Vol.37(2), pp.211-218
    Description: Published data on the toxicity of metal ions to aquatic biota, in particular Daphnia magna , were analyzed for their correlation with ion specific physico-chemical parameters. Significant correlations were obtained for three groups of ions with similar electron configurations in the outer orbitals. Group I ions include Na (I), Be (II), Ba (II), Al (III), and Cr (VI) with inert gas-like electron configurations; group II ions include Cr (III), Mn (II), Fe (III), Co (II), Ni (II), Cu (II), Zn (II), As (V), Cd (II), Pt (IV), Au (III), and Hg (II) with partially or completely filled d electron orbitals; group III ions include Sn (II), As (III), Se (IV), and Pb (II), with filled d and s , but unfilled p electron orbitals. The toxicity of an ion within a group can be calculated from the general equation where pT is the negative logarithm of a metal ion concentration with a certain toxicity in mol∙L 1 ; AN is the metal's atomic number; IP is the difference between the ion's ionization potential with the oxidation number ( OX ) and the ionization potential of the next lower oxidation number ( OX 1) in electron volts (eV); and E 0 is the absolute value of the electrochemical potential between the ion and the first stable reduced state. The values for the constants a 0 , a 1 , and a 2 depend on the group of ions, the biota, and the particular toxic effect determined. The equation is applied to predict the toxicities of other ions under similar test conditions. Key words : toxicity, metals, ions, correlations, Daphnia magna , aquatic tests
    Description: Nous avons analys les donnes publies sur la toxicit d'ions mtalliques dans les biocnoses aquatiques, en particulier Daphnia magna , afin de dterminer s'il y a corrlation entre ceux-ci et des paramtres physico-chimiques spcifiques aux ions. On a trouv des corrlations significatives chez trois groupes d'ions configurations lectroniques identiques dans les orbitales externes. Les ions du groupe I comprennent : Na (I), Be (II), Ba (II). Al (III) et Cr (VI) configurations lectroniques semblables celles des gas inertes; les ions du groupe II comprennent : Cr (III), Mn (II), Fe (III), Co (II), Ni (II), Cu (II), Zn (II), As (V), Cd (II), Pt (IV), Au (III) et Hg (II) orbitales lectroniques d partiellement ou entirement remplies; les ions du groupe III comprennent : Sn (II), As (III), Se (IV) et Pb (II) orbitales lectroniques d et s remplies, mais p non remplie. L'quation gnrale suivante peut servir calculer la toxicit d'un ion au sein d'un groupe : O pT est le logarithme ngatif d'une concentration d'ions mtalliques d'une toxicit donne en mol∙L 1 ; AN est le nombre atomique du mtal; IP est la diffrence entre le potentiel d'ionisation de l'ion dont le nombre d'oxydation est OX et le potentiel d'ionisation du nombre d'oxydation immdiatement au-dessous ( OX 1), en lectron volt (eV); et E 0 est la valeur absolue du potentiel lectrochimique entre l'ion et le premier tat rduit stable. Les valeurs des constantes a 0 , a 1 et a 2 dpendent du groupe d'ions, de la biocnose et de l'effet toxique particulier trouv. A l'aide de cette quation, nous prdisons la toxicit d'autres ions dans des conditions d'essais identiques.
    Keywords: Monitoring and Analysis of Water and Wastes ; Animals (Invertebrates) (See Also Individ Groups) ; Jn - Can. J. Fish Aquat. Sci. ; Jn - Canadian Journal of Fish and Aquatic Science;
    ISSN: 0706-652X
    E-ISSN: 1205-7533
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  • 4
    In: Canadian Journal of Fisheries and Aquatic Sciences, 1995, Vol.52(2), pp.268-275
    Description: This study shows that persistent organochlorine contaminants, including PCBs, reached higher concentrations in lamprey of the St. Lawrence River basin 40 years ago. A comparison was made of the concentrations of 22 organochlorine pesticides and 93 polychlorinated biphenyl (PCB) congeners in formalin-preserved lamprey ammocoetes collected between 19471950 and in 1990 in the St-Franois and Ste-Anne rivers, St. Lawrence River basin, Qubec. Eight pesticides (-BHC, -Chlordane, -Chlordane, p , p -DDD, o , p -DDE, p , p -DDE, p , p -DDT, and Heptachlor) reached higher concentrations in the earlier period, with Mirex being the only pesticide found in higher concentrations in 1990. Seventeen PCB congeners (24(27), 28, 98(84), 101, 110(77), 128, 129, 141, 149, 151, 158, 174, 177, 180, 183, 187(182), and 198) had higher concentrations in the 19471950 period compared with 1990. A significant inverse relationship was found between the concentration of the various PCB congeners and sampling date. The concentrations of DDT have decreased significantly, while its metabolites, DDD and DDE, have increased significantly over the last 40 years.
    Description: Cette tude a permis de dmontrer que les contaminants organochlors persistants, y compris les BPCs, atteignaient des concentrations plus leves dans les lamproies du bassin fluvial du St-Laurent il y a 40 ans. Nous avons compar les concentrations de 22 pesticides organochlors ainsi que les concentrations de 93 congnres de biphnyles polychlors (BPCs) dans des ammoctes de lamproies prserves dans le formol, chantillonnes en 19471950 et en 1990 dans les rivires St-Franois et Ste-Anne, bassin du fleuve St-Laurent, Qubec. Huit pesticides (-BHC, -Chlordane, -Chlordane, p , p -DDD, o , p -DDE, p , p -DDE, p , p -DDT, et Heptachlor) affichaient des concentrations plus leves dans la priode antrieure et le Mirex fut le seul pesticide atteindre une plus haute concentration en 1990. Dix-sept congnres de BPCs (24(27), 28, 98(84), 101, 110(77), 128, 129, 141, 149, 151, 158, 174, 177, 180, 183, 187(182) et 198) affichaient des concentrations plus leves dans la priode 19471950 comparativement 1990. Une relation inverse statistiquement significative existe entre la concentration des divers congnres de BPCs et la date d'chantillonnage. La concentration du DDT a diminu de faon significative tandis que ses mtabolites, le DDD et le DDE, ont augment de faon significative au cours des 40 dernires annes.
    Keywords: River Basins ; Larvae ; Organochlorine Compounds ; Pesticides ; Historical Ecology ; Bioaccumulation ; River Basins ; Larvae ; Organochlorine Compounds ; Ddt ; Dde ; Pesticides ; Pcb Compounds ; Bioaccumulation ; Polychlorinated Biphenyls ; River Basins ; Larvae ; Ddd ; Ddt ; Dde ; Pesticides ; Bioaccumulation ; Canada, Quebec ; Pollution Monitoring and Detection ; Environmental Impact ; Freshwater Pollution ; Effects of Pollution ; Fish ; Ddd ; Dde ; Ddt ; Hyperoartia ; Pcb ; Pcb Compounds ; Historical Ecology ; Organochlorine Compounds ; Pesticides (Organochlorine) ; Polychlorinated Biphenyls;
    ISSN: 0706-652X
    E-ISSN: 1205-7533
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  • 5
    Language: English
    In: Chemosphere, 1999, Vol.38(14), pp.3237-3245
    Description: The use of probabilistic neural networks (PNN) to model the acute toxicity (96 h LC50) to the fathead minnow (Pimephales promelas), based on 865 chemical data sets, is described. The octanol/water partition co-efficient was not used as an input parameter and the information fed into the PNN was solely based on simple molecular descriptors that could be derived from the chemical structure. An extensive list of functional group descriptors is provided and the development of a model and cross validation procedures is explained. Predictions resulted from procedures involved in 5 subsets, each containing 20 per cent of the data, and compared to measured (expected) output data. High values of the correlations between the measured and predicted values strongly suggested the use of linear correlation to improve the model. The excellent statistics obtained with the PNN model indicate its applicability to a great variety of compounds.
    Keywords: Fathead Minnow ; Acute Toxicity ; Neural Network ; Model ; Prediction ; Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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  • 6
    Language: English
    In: Chemosphere, 1983, Vol.12(9), pp.1159-1167
    Description: An investigation is described of the effects of increasing halogen substitution on octanol/water partition coefficients of a variety of aromatic and heterocyclic parent molecules. It is suggested that the increasing chlorine substitution of compounds such as benzene, aniline, pyridine and diphenyl results in declining increases of the octanol/water partition coefficients. Two equations are derived which allow the quick estimation of the partition coefficient of any congener from the known value of another. These equations are of particular value for compounds the partition coefficients of which are difficult to determine experimentally, for the prediction of their environmental fates and bioaccumulation potentials and for their toxicities, which often correlate with their partition coefficients.
    Keywords: Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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  • 7
    In: Canadian Journal of Fisheries and Aquatic Sciences, 1995, Vol.52(2), pp.276-282
    Description: Lamprey ammocoetes were determined to be as suitable as adult bivalve molluscs for monitoring persistent organochlorine contaminants in the freshwater environment. Ammocoetes of four lamprey species and adults of three bivalve mollusc species, collected from the same seven rivers of the St. Lawrence River basin in Qubec, were assayed for 21 organochlorine pesticides and for polychlorinated biphenyl (PCB) congeners. All organochlorine compounds assayed were detected in one or more of the 15 lamprey samples whereas Aldrin, -BHC, and PCB congeners 1, 3, 12(13), 29, 54, 189, 191, and 199 were not detected in any of the nine bivalve samples. Nine pesticides (Aldrin, Dieldrin, -BHC, -Chlordane, -Chlordane, o , p -DDD, p , p -DDD, p , p -DDT, and a-Endosulfan) had higher concentrations in the lampreys. PCB congeners 167(185) and 209 had higher concentrations in bivalves. PCBs accounted for 96.699.4% of the organochlorine lipid burden in bivalves, but only 33.476.8% in lampreys. On average, ammocoetes had 44 times more lipids per body dry weight than did bivalves. The differences observed in concentrations and types of organochlorine compounds found in the two taxa may be due to differences in the amounts (observed) and types (postulated) of body lipids they each possess.
    Description: Cette tude a dmontr que les ammoctes de lamproies sont aussi appropries que les mollusques bivalves adultes comme baromtres des niveaux de contaminants organochlors persistants dans le milieu dulaquicole. Les concentrations de 21 pesticides organochlors ainsi que celles de congnres de biphnyles polychlors (BPCs) furent dtermines chez des ammoctes de quatre espces de lamproies et des adultes de trois espces de mollusques bivalves, chantillonns de faon sympatrique dans sept rivires du bassin fluvial du St-Laurent au Qubec. Tous les composs organochlors valus furent dcels dans un ou plus des 15 chantillons de lamproies. Par contre, l'Aldrin, le -BHC et les congnres de BPCs 1, 3, 12(13), 29, 54, 189, 191 et 199 n'ont t dcels dans aucun des neuf chantillons de bivalves. Neuf pesticides (Aldrin, Dieldrin, -BHC, -Chlordane, -Chlordane, o , p -DDD, p , p -DDD, p , p -DDT et -Endosulfan) affichaient de plus hautes concentrations chez les lamproies. Les congnres 167(185) et 209 affichaient de plus hautes concentrations chez les bivalves. Les BPCs comptaient pour 96,699,4% du fardeau lipidique d'organochlors chez les bivalves, mais seulement 33,476,8% chez les lamproies. Les ammoctes avaient en moyenne 44 fois plus de lipide par unit de poids corporel sec que les bivalves. Nous formulons l'hypothse que les diffrences observes chez les deux taxons quant aux concentrations et aux types de composs organochlors retrouvs, sont dues des diffrences dans les montants (observs) et les types (postuls) de tissus lipidiques qu'ils possdent.
    Keywords: Bivalvia ; Bivalvia ; Canada, Quebec ; Canada, Quebec ; Canada, Quebec ; Bivalvia ; Bivalvia ; Organochlorine Compounds ; Organochlorine Compounds ; Lipids ; Lipids ; Bioindicators ; Bioindicators ; Pcb Compounds ; Pcb Compounds ; Pesticides ; Pesticides ; Organochlorine Compounds ; Indicator Species ; Lipids ; Pesticides ; Organochlorine Compounds ; Indicator Species ; Lipids ; Pesticides ; Pollution Monitoring and Detection ; Environmental Impact ; Freshwater Pollution ; Freshwater Pollution ; Fish ; Molluscs ; Hyperoartia ; Indicator Species ; Pesticides (Organochlorine) ; Pcb ; Hyperoartia ; Pesticides (Organochlorine) ; Pcb ; Bioindicators ; Pcb Compounds ; Hyperoartia ; Pesticides (Organochlorine) ; Pcb ; Bioindicators ; Pcb Compounds ; Hyperoartia ; Pcb ; Pcb Compounds ; Bioindicators ; Indicator Species ; Pesticides (Organochlorine);
    ISSN: 0706-652X
    E-ISSN: 1205-7533
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  • 8
    Language: English
    In: Journal of Molecular Structure: THEOCHEM, 2003, Vol.622(1), pp.85-95
    Description: This review surveys the applications of neural network (NN) methodologies to the field of Quantitative Structure–Activity Relationships (QSARs) in aquatic toxicology. Several NN methods have been applied to substantial data sets (some involving over 1000 chemicals) for acute and sublethal toxicity endpoints for fish, invertebrate, protozoan and bacterial species. The results clearly demonstrate the methods' general ability to detect and apply non-linear structure–activity relationships for the prediction of the corresponding values for compounds not part of the training sets.
    Keywords: Quantitative Structure–Activity Relationships ; Neural Networks ; Aquatic Toxicity ; Large Data Sets ; Chemistry ; Physics
    ISSN: 0166-1280
    E-ISSN: 1872-7999
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  • 9
    Language: English
    In: Chemosphere, 1993, Vol.27(7), pp.1159-1169
    Description: In comparison to traditional “index-card-type” databases, spreadsheets can hold much the same information, but allow much more manipulation and use of the data contents. Until recently, spreadsheets were limited by computer power, i.e. speed, memory and programs of the budget priced available hardware and software. With the availability of new, more effective spreadsheet software, such as Quattro ® Pro for Windows ™ , and much faster “386” and “486” desktop computers at a much reduced cost, the potential of spreadsheets to hold and manipulate scientific databases has developed into a new powerful research tool. We have now compiled a toxicity database in spreadsheet format, which contains acute and sub-chronic toxicity data on approximately 1500 chemicals for aquatic and terrestrial species, together with various physico-chemical and topological data. This paper provides an overview of the spreadsheet-type database structure and capabilities using the COMPUTOX ™ toxicity database as an example to show the development of qualitative and quantitative relationships of acute toxicities of organic chemicals between various species and/or endpoints, with emphasis on the Microtox ™ ( Photobacterium phosphoreum ) toxicity test.
    Keywords: Desktop Computer ; Spreadsheet ; Research Tools ; Acute Toxicity ; Correlations ; Plotting ; Microtox ; Photobacterium Phosphoreum ; Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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  • 10
    Language: English
    In: Science of the Total Environment, 1994, Vol.142(3), pp.179-190
    Description: The Microtox super(TM) values (acute toxicities to Photobacterium phosphoreum) of 85 nitrobenzene derivatives are reported, along with the results of ab initio (minimal basis, STO-3G) and semi-empirical (AM1) molecular orbital calculations of electronic properties. QSARs are developed between the acute toxicities and the various calculated parameters. The more rapid semi-empirical calculations are compared to the ab initio results and the advantages and disadvantages of the two methods are considered. As in earlier work, the change in the electronic charge distribution on the nitro group, (QO), in compounds with strongly electron withdrawing substituents, is found to be a significant indicator of high toxicities. The data set is comprised of di-, tri- and tetra substituted compounds. The effect of the increase in the number of substituents and their relative positions on the ring are considered as possible factors affecting acute toxicity. For compounds in which the nitro group is ortho to a substituent with which it may hydrogen-bond, the charge on the nitro group ceases to be a useful indicator of toxicity. The energy of the Highest Occupied Molecular Orbital (HOMO) is found to be highly correlated with QO and alternates with it as the significant parameter in some regressions.
    Keywords: Qsar ; Microtox TM ; Nitrobenzene Derivatives ; Molecular Orbitals ; Homo ; Lumo ; Environmental Sciences ; Biology ; Public Health
    ISSN: 0048-9697
    E-ISSN: 1879-1026
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