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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

Over de ontwikkeling, de determinatie en de betekenis van de epiphyse en de paraphyse van de amphibiën

Kamer, Johan Cornelis van de. January 1900 (has links)
Proefschrift - Utrecht / Summary in English.
12

Mercury bioaccumulation and habitat relations of lotic and lentic amphibians from Acadia Aational Park, Maine, USA /

Bank, Michael S., January 2005 (has links) (PDF)
Thesis (Ph.D.) in Ecology and Environmental Science--University of Maine, 2005. / Includes vita. Includes bibliographical references (leaves 111-135).
13

Population trends, conservation and the trade in amphibians in Asia /

White, Steve, January 2005 (has links)
Thesis (M. Sc.)--University of Hong Kong, 2005.
14

The morphology of the nasal region of Amphibia and its bearing of the phylogeny of the group,

Jurgens, J. D. January 1971 (has links)
Thesis--University of Stellenbosch. / Bibliography: p. 136-146.
15

Terrestrial habitat use by pool-breeding amphibians in a suburban landscape /

Regosin, Jonathan V. January 2003 (has links)
Thesis (Ph.D.)--Tufts University, 2003. / Adviser: J. Michael Reed. Submitted to the Dept. of Biology. Includes bibliographical references (leaves 124-134). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
16

Ontogeny and phylogeny of small dissorophoid amphibians

Fröbisch, Nadia B. January 1900 (has links)
Thesis (Ph.D.). / Written for the Dept. of Biology. Title from title page of PDF (viewed 2008/01/12). Includes bibliographical references.
17

Development of the gastro-intestinal regulation in the axolotl (Ambystoma mexicanum)

Badawy, Gamal Metwally January 2002 (has links)
No description available.
18

Capitosaurid amphibians from the upper Luangwa Valley, Zambia

Chernin, Sharon 13 January 2015 (has links)
No description available.
19

Pesticides and amphibian declines in the Sierra Nevada Mountains, California

Cowman, Deborah Fay 25 April 2007 (has links)
Pacific chorus frog (Pseudacris regilla) hatchlings were translocated and placed in cages in sites (~2,200 m elevation) located in Lassen, Yosemite, and Sequoia National Parks. DDE was found in 97% of Yosemite National Park samples, 84% in Sequoia National Park samples, and 15% of Lassen Volcanic National Park samples in 2001 and 2002. Total endosulfans were detected in 3% of Sequoia samples, 9% of Lassen samples and 24% of Yosemite samples. Both pesticides were detected in tadpoles and metamorphs raised at the three parks regardless of origin. Because the tadpoles were translocated post hatching, this finding indicates that the pesticides, particularly DDE, were accumulated at the site, instead of through deposition in the egg mass. Liver cells from 108 newly metamorphosed frogs were examined with flow cytometry (FCM) techniques for evaluation of chromosome breakage as measured by the half-peak coefficient of variation (HPCV) of the G1 peak. Regardless of origin, experimental groups raised at Lassen, the reference site, had significantly less chromosomal breakage (p=0.04) than metamorphs raised at the other two parks. This is the first documented evidence of DNA damage in juvenile frogs in the Sierra Nevada Mountains. Cholinesterase (ChE) was measured in tadpoles collected at 28 days and in juvenile frogs collected upon metamorphosis. In 2001, ChE activity was significantly higher in animals raised at Lassen (reference site), than at the other two parks, indicating less exposure to cholinesterase-inhibiting pesticides. This trend was not observed in 2002, although Sequoia ChE values were consistently lower than the other two parks. Temperatures were significantly different among the three parks for both years (p<0.0001) and lower temperatures may correlate with lower ChE levels. Survivorship to metamorphosis, days to metamorphosis, snout-vent lengths (SVL), and malformations were evaluated. Animals raised in Sequoia had shorter SVLs, took longer to metamorphose, and had lower survivorship to metamorphosis than in the other two parks (p<0.0001). Effects noted in P. regilla may be magnified in long lived ranid species. These findings may be important in evaluating the overall impact of aerially transported pesticides on declining frog populations in the Sierra Nevada Mountains.
20

Pesticides and amphibian declines in the Sierra Nevada Mountains, California

Cowman, Deborah Fay 25 April 2007 (has links)
Pacific chorus frog (Pseudacris regilla) hatchlings were translocated and placed in cages in sites (~2,200 m elevation) located in Lassen, Yosemite, and Sequoia National Parks. DDE was found in 97% of Yosemite National Park samples, 84% in Sequoia National Park samples, and 15% of Lassen Volcanic National Park samples in 2001 and 2002. Total endosulfans were detected in 3% of Sequoia samples, 9% of Lassen samples and 24% of Yosemite samples. Both pesticides were detected in tadpoles and metamorphs raised at the three parks regardless of origin. Because the tadpoles were translocated post hatching, this finding indicates that the pesticides, particularly DDE, were accumulated at the site, instead of through deposition in the egg mass. Liver cells from 108 newly metamorphosed frogs were examined with flow cytometry (FCM) techniques for evaluation of chromosome breakage as measured by the half-peak coefficient of variation (HPCV) of the G1 peak. Regardless of origin, experimental groups raised at Lassen, the reference site, had significantly less chromosomal breakage (p=0.04) than metamorphs raised at the other two parks. This is the first documented evidence of DNA damage in juvenile frogs in the Sierra Nevada Mountains. Cholinesterase (ChE) was measured in tadpoles collected at 28 days and in juvenile frogs collected upon metamorphosis. In 2001, ChE activity was significantly higher in animals raised at Lassen (reference site), than at the other two parks, indicating less exposure to cholinesterase-inhibiting pesticides. This trend was not observed in 2002, although Sequoia ChE values were consistently lower than the other two parks. Temperatures were significantly different among the three parks for both years (p<0.0001) and lower temperatures may correlate with lower ChE levels. Survivorship to metamorphosis, days to metamorphosis, snout-vent lengths (SVL), and malformations were evaluated. Animals raised in Sequoia had shorter SVLs, took longer to metamorphose, and had lower survivorship to metamorphosis than in the other two parks (p<0.0001). Effects noted in P. regilla may be magnified in long lived ranid species. These findings may be important in evaluating the overall impact of aerially transported pesticides on declining frog populations in the Sierra Nevada Mountains.

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