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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Contributions to the knowledge of the young-Caenozoic Ostracoda from the Malayan region

Kingma, Jacobus Theodorus. January 1948 (has links)
Proefschrift--Utrecht. / "Stellingen": [2] p. inserted. Bibliography: p. 103-106.
12

Contributions to the knowledge of the young-Caenozoic Ostracoda from the Malayan region

Kingma, Jacobus Theodorus. January 1948 (has links)
Proefschrift--Utrecht. / "Stellingen": [2] p. inserted. Bibliography: p. 103-106.
13

Ostracodes of the family Beyrichiidae from the Silurian of Gotland

Martinsson, Anders. January 1962 (has links)
Thesis--Uppsala, 1962. / Includes bibliographical references.
14

Type Saline Bayou ostracoda of Louisiana

Howe, Robert Crombie, January 1962 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1962. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 90-94).
15

Taxonomy of Ordovician ostracodes from western Newfoundland, Anticosti Island and the St. Lawrence lowlands of Québec /

Pitman, David John, January 1991 (has links)
Thesis (Ph. D.)--Memorial University of Newfoundland. / Restricted until October 1992. Typescript. Bibliography: leaves 242-281. Also available online.
16

The holocene ostracods of the Agulhas Bank, South Africa : their classification, distribution and ecology

Conway-Physick, Jessica Ann January 1995 (has links)
Bibliography: pages 69-77. / An analysis of the Holocene ostracod fauna of the Agulhas Bank has been carried out on seventy-three surficial sediment samples. Sixty-six species of Ostracoda have been recorded, of which fifty-nine species are accounted for in forty genera and the remaining seven species are of indeterminate classification. The species are described and their distribution and ecology is given. An. analysis of the sedimentology, as well as an oceanographic analysis of the bottom water on the Agulhas Bank, has provided environmental parameters for each sediment sample location, enabling relationships to be described between ostracod faunas and environmental conditions. Quantitative factor analysis has been carried out on the twenty-four most abundant species, generating seven factor associations relating ostracod assemblages to a set of environmental parameters. The independent variables analyzed were the temperature, salinity and dissolved-oxygen content of the bottom water, as well as the sand content of the sediment. Contour maps of these variables have been drawn up using SADCO data for the oceanographic variables, and the sediment samples to calculate the sand content. The overall oceanography of the Agulhas Bank has been analyzed by relating the environmental parameters generated at each location to the water masses present on the shelf, and to the oceanic currents affecting them. Finally, the seven factor associations generated have been related directly to the substrate types, the water masses, and the currents present on the Agulhas Bank.
17

A study of the taxonomy and some aspects of the ecology of marine ostracods in the plankton of Indian Arm, British Columbia

McHardy, Robert Alexander January 1961 (has links)
In 1960 a program was carried out to study some aspects of the distribution of planktonic ostracods in Indian Arm, an inlet of the coast of British Columbia. As a result, Paradoxostoma striungulum Smith, Phllomedes sp., Conchoecia elegans Sars, and C. pseudohamata n.sp. were collected, described and illustrated. Of these species, C. elegans and C, pseudohamata were abundant in the plankton, and provided material for the diagnoses of growth stages and for the comparison of the adult stages with those collected from other British Columbia inlets and from the Ocean Weather Station ”P” (50° N., 145° W.) The distributions of Conehoecia elegans and C. pseudohamata were studied in relation to temperature, salinity, oxygen, and light. The species were seldom found in water above the thermocline and halocline. The general distributions of Conehoecia elegans and C. pseudohamata may have been partly influenced by the mixing between water long resident in Indian Arm and water entering by way of the mouth of the Inlet. . Both species generally inhabited waters having temperatures from 7 to 9° C, and salinities from 26 to 27°/₀₀. Both occurred at depths greater than the shallow sill at the mouth; the one living more deeply seems to have been more restricted to the inlet than the other. Diurnal vertical migration differed for the two species except within the shallower part of the water column, where both seem to have descended in the presence of light. The time of maximal breeding seems to have been in the early summer for Conchoecia elegans and from early summer to early autumn for C. pseudohamata. Examination of stomach contents shows that both species were omnivorous. / Science, Faculty of / Zoology, Department of / Graduate
18

Palaeogene ostracods from the South African continental shelf

Frewin, J January 1987 (has links)
Bibliography: pages 147-155. / 92 cytheracean species, representing 44 genera are recorded from the Palaeogene Agulhas Bank and west coast margin of South Africa. 11 genera and 3 species are common with the Upper Cretaceous faunas. 12 genera (18 species) are left in open nomenclature. The following genera are represented:- Bythoceratina, Incongruellina, Ruggieria, Eucythere, Krithe, Parakrithe, Eucytherura, Cytheropteron, Ambostracon, Urocythereis, Muellerina, Leguminocythereis, Loxoconcha, Schlerochilus, Poseidonamicus, Bradleya, Agrenocythere, Australileberis, Chrysocythere, Costa, Echinocythereis, Haughtonileberis, Henryhowella, Parvacythereis, Phacorhabdotus, Soudanella, Stigmatocythere, Togoina, Trachyleberis, Veenia, Atlanticythere, Xestoleberis. Data on South African Cretaceous and Palaeogene ostracod faunas are discussed in terms of: faunal associations for the South African Palaeogene JC-1, Agulhas Bank and west coast provinces; characteristic species of Upper Eocene and Upper Eocene to Oligocene strata; generic variations across the Cretaceous/Tertiary boundary. Palaeo-environmental trends from a Cytheracea, Cypridacea + Bairdiacea, Cytherellidae (CCBC) plot indicate a sea level change from <100m (Palaeocene- Eocene), to shallower water with restricted circulation (Upper Eocene) to moderate depth, 100 - 200m (Lower Oligocene). South African faunas are compared with those from adjacent Palaeogene ostracod faunal provinces. Strong generic links occur with West Africa (8 genera in common) and Pakistan (9 genera in common) with only 3 genera in common with Australia and 3 with Argentina.
19

A discussion of the Cytherinae (Ostracoda) with description of two new species

Watling, Leslie Edward 01 January 1969 (has links)
This paper is concerned with the description of two new ostracod species, and the discussion of their affinities with other species in the subfamily Cytherinae. In this discussion reference is made to the morphological features of several genera. At this point it must be made clear that although the original type descriptions were used, the author has never seen the type specimens. Thus, all discussion is based on these original descriptions as well as on available supplementary material.
20

Uso da espectroscopia no infravermelho com transformada de Fourier na avaliação de efeitos ecotoxicológicos subletais sobre Ostracodes Chlamydoteca sp. / Use of Fourier-transform infrared spectroscopy in the assessment of sublethal ecotoxicological effects on Ostracods Chlamydoteca sp.

Sepúlveda, Priscila dos Santos 30 July 2018 (has links)
Com o crescimento populacional e aumento das atividades humanas, grandes quantidades de poluentes são despejadas diariamente no meio ambiente. Nos ecosssistemas aquáticos, organismos são expostos por longos períodos à baixas concentrações de contaminantes. Assim estudos que focam em novas metodologias que sejam rápidas e não invasivas, são necessários para a avaliação de efeitos subletais. Um exemplo é a espectroscopia no infravermelho com transformada de Fourier (FTIR). Esta técnica é capaz de detectar alterações macromoleculares em amostras biológicas de forma rápida e não destrutiva, sendo uma ferramenta atrativa para análises ecotoxicológicas. Assim, o objetivo deste estudo foi verificar a aplicabilidade do FTIR como metodologia alternativa, utilizando perfis de composição macromoleculares como indicadores de efeitos subletais, em organismos expostos a elementos-traço. Para tal, ostrácodes (Chlamydoteca sp.) foram expostos aos elementos Cu, Cd, Hg e Mn. As alterações em perfis biomoleculares foram avaliadas em ostrácodes expostos por 48h ao Mn. Os resultados revelaram uma correlação negativa entre concentração de exposição e proporção de ácidos graxos saturados e insaturados com relação à proteína em organismos expostos ao Mn e a mesma correlação foi observada para o conteúdo de ácidos nucléicos. Isto sugere que os organismos tiveram seu metabolismo lipídico e sua capacidade de produção de proteína celular alterados devido à exposição ao Mn. Ademais, foram realizados testes crônicos (9 dias) com ostrácodes expostos ao Cu, Cd, Hg e Mn. Foi observada a diminuição de lipídios saturados e insaturados em relação à proteína em organismos expostos ao Cd, sugerindo o uso de reservas lipídicas devido ao estresse fisiológico. Ostrácodes expostos ao Cu, tiveram o aumento dos ácidos nucléicos, no qual o DNA pode ter sido o componente dominante. Alterações significativas relacionadas ao conteúdo de carbonato de cálcio foram reveladas nos organismos expostos ao Cd e ao Cu, o que sugere mudanças na composição da carapaça e possível alteração na capacidade de muda e crescimento dos organismos. Portanto, este estudo permite concluir que a espectroscopia de FTIR é capaz de detectar indícios de efeitos subletais em organismos expostos a contaminantes e que as alterações de composição macromolecular são uma ferramenta complementar promissora para futuras avaliações ecotoxicológicas. / With population growth and increases in human activities, large amounts of pollutants are released daily into the environment. In aquatic ecosystems organisms are exposed for long periods at low concentrations of contaminants. Therefore, studies that focus on fast and non-invasive new methodologies are necessary for the assessment of sublethal effects in organisms. An example is the Fourier Transform Infrared Spectroscopy (FTIR). This technique can detect macromolecular changes of biological samples in a fast, inexpensive and non-destructive way, all of which lend to the attractiveness of this methodology for ecotoxicological analyzes. Thus, the aim of this study was to verify the applicability of FTIR as an alternative methodology, using the composition of macromolecular profiles as an indicator of sublethal effects in organisms exposed to trace elements. For this, ostracods (Chlamydoteca sp.) were exposed to the elements Cu, Cd, Hg and Mn. Changes in biomolecular profiles were evaluated in ostracods exposed for 48h to Mn. The results showed a negative correlation between the concentration of exposure and the proportion of saturated and unsaturated fatty acids for protein in organisms exposed to Mn and the same correlation was observed for the content of nucleic acids. This suggests that the organisms had their lipid metabolism and their cellular protein production capacity altered due to Mn exposure. In addition, four chronic tests (9 days) were performed on ostracods exposed to the trace elements Cu, Cd, Hg and Mn. A decrease in saturated and unsaturated lipids in relation to the protein was observed in organisms exposed to Cd, suggesting that the use of lipid reserves was due to the physiological stress. Ostracods exposed to Cu had an increase in nucleic acids, in which DNA may have been the dominant component. Significant changes related to the calcium carbonate content were revealed in the organisms exposed to Cd and Cu, which suggests changes in carapace composition and the possible alteration in the organism capacity of molting and growth. Therefore, this study concludes that FTIR spectroscopy can detect indications of sublethal effects in organisms exposed to contaminants and that changes in macromolecular composition are a promising complementary tool for future ecotoxicological assessments.

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