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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.
91

Population structure and microphylogeographic patterns of dolly varden (Salvelinus malma) along the Yukon North Slope /

Rhydderch, James Gareth, January 2001 (has links) (PDF)
Thesis (M.S.)--University of Guelph, 2001. / Includes bibliographical references. Also available via the Internet.
92

Reproducing the River: Historic Context and Resource Survey of Oregon’s State Fish Hatchery System

Bohner, Rodney 31 October 2018 (has links)
Oregon’s fish hatchery system developed in the late 1800’s in response to salmon fishery losses. Salmon hatcheries consist of a number of built components. ‘Growing fish’ requires a variety of building types which support the hatchery process as well as constant input of resources. In addition to surveying and inventorying fish hatchery resources, this study will analyze the social, economic, cultural, and environmental conditions under which these fish hatcheries were organized and commissioned. Ultimately, this survey will not only serve as a baseline for future, more intensive-level surveys, but will also provide a foundation for a National Register Multiple Property Submission. The use of hatcheries to sustain native Oregon fish species constitutes a major aspect of Oregon’s fishing and environmental conservation efforts. Oregon’s heritage hatcheries stand as physical reminders of early conservation activity and while their preservation provides a more complete picture of Oregon’s relationship with natural resources
93

Aspects of the morphology, parasite host specificity and genetics of selected Labeobarbus polylepis populations

Austin, Amanda 13 April 2011 (has links)
M.Sc. / The Bushveld smallscale yellowfish, Labeobarbus polylepis (Boulenger, 1907), is an ecologically, socially and economically important species. These indigenous freshwater fish are found above an altitude of 600m, and occur in the Inkomati and Phongolo River Systems and the southern tributaries of the Limpopo River System. In the past, it was suspected that morphological differences exist between the different L. polylepis populations, due to the occurrence of the rubberlip formation of individuals from the Elands River. Specimens of five L. polylepis populations were collected from the Phongolo, Assegaai, Elands and Komati rivers and Ngodwana Dam, Mpumalanga, South Africa. A L. natalensis population was collected from the Umvoti River and used as an out-group. Nine meristic counts and 46 morphometric measurements were taken. The measurements were changed into percentage ratios based on the fork length of each individual. The data was statically analysed and includes Multidimensional scaling techniques (MSD’s) and Principle Component Analysis (PCA’s). Statistical analysis split the five populations into three groups. The one group consists of fish from the Phongolo and Assegaai rivers, the second group consists of fish from the Elands River and Ngodwana Dam and the third group is mainly Komati River fish. The third group is the only group that does not overlap with any other group. There were morphological differences between the groups, but they were not significant. The L. natalensis population is morphologically similar to L. polylepis populations obtained from the Phongolo and Assegaai rivers. Twenty enzyme coding loci in two L. polylepis populations from the Phongolo and Elands rivers were analysed by horizontal starch gel-electrophoresis. Electrophoretic analysis of heart, muscle and liver tissue samples revealed genetic variation at 15% (Elands River) and 35% (Phongolo River) of the protein coding loci studied. Average heterozygosity values based on Hardy-Weinberg expectation were 0.019 (Elands River) and 0.059 (Phongolo River), with a genetic distance value of 0.004 between these populations.
94

A microchemical analysis of native fish passage through Brandon Road Lock and Dam, Des Plaines River, Illinois

Snyder, Claire 01 August 2019 (has links)
Modifications to Brandon Road Lock and Dam (BRLD), located on the Des Plaines River in northeastern Illinois, have been proposed to prevent the upstream transfer of aquatic invasive species, particularly Asian carps, into the Great Lakes Basin. These modifications, including the installation of an electric barrier, acoustic fish deterrent, and air bubble curtain, are designed to completely eliminate all upstream fish passage and may negatively impact native fish populations in the Des Plaines River by reducing upstream movement and potentially fragmenting populations. BRLD is situated just 21 km upstream of the Des Plaines River mouth, and fish are only able to pass upstream via the lock chamber. Fish species richness within the Des Plaines River watershed has increased over the last 35 years. It has been suggested that the majority of new species to the upper Des Plaines River have migrated upstream past Brandon Road Lock and Dam (BRLD), from the Illinois, Kankakee, and lower Des Plaines rivers. However, documentation of emigration needed to support that contention is lacking and there is limited knowledge of the current rate of BRLD passage by native species. To assess native fish passage through the lock, a microchemical study was conducted using fin rays from fish collected from the Des Plaines, Illinois, and Kankakee Rivers. The edge of each fin ray, which contained the most recently deposited material, was assumed to contain a microchemical signature reflective of residency in the river where the fish was sampled. Fin ray edge strontium:calcium ratio (Sr:Ca) was used to define taxonomic and river-specific signature ranges for four taxonomic groups: centrarchids, catostomids, ictalurids, and lepisosteids. Fin ray edge Sr:Ca data were input into a random forest classification model, and the classification accuracy of fish to their river of capture based on their fin ray edge Sr:Ca was > 97% in each taxonomic group. The classification model was then applied to the entire fin ray of each fish sampled upstream of Brandon Road to infer retrospective environmental history. Upstream BRLD lock passage was suggested by the presence of Sr:Ca signatures indicative of prior downstream residency in the Illinois or Kankakee rivers in a fish sampled upstream of BRLD. Results indicated some evidence of downstream residency that suggested upstream BRLD lock passage for centrarchids, catostomids, ictalurids, and lepisosteids, ranging from 15 – 37% of individuals sampled depending on taxa. An additional 19 – 80% of individuals within each taxonomic group were classified as fish with uncertain downstream residency, whereby the possibility of BLRD lock passage could not be rejected, but there was higher uncertainty in establishing downstream residency in the Illinois or Kankakee rivers. The impact of BRLD modifications and passage restriction on Des Plaines River fish populations is unknown and merits further investigation.
95

Establishing and Evaluating Agricultural Plantings and Supplemental Cover on Reservoir Mudflats as a Means to Increase Juvenile Game Fish Abundance and Growth

Hatcher, Hunter R 14 December 2018 (has links)
Reservoirs throughout the country exhibit degraded shorelines and simplified littoral habitats because of aging. This study evaluated the establishment of agricultural plantings on reservoir mudflats and the effectiveness of supplemental brush pile structures in providing recruitment habitat for juvenile fish. The mudflats of Enid Reservoir, Mississippi were seeded during the winter drawdown in October of 2016 and 2017 with agricultural plantings. Monitoring of plantings found grasses performed best in terms of establishment and providing potential fish habitat. During Summer 2017 brush piles and control sites, without brush, were sampled in Enid Reservoir using rotenone to evaluate juvenile fish use. Juvenile fish exhibited greater abundances and larger sizes, on average, in brush pile sites. Larger brush piles placed in shallower water provided the greatest benefit to juvenile fish.
96

Accleration of fish sauce fermentation using proteolytic enzymes

Chaveesuk, Ravipim January 1991 (has links)
No description available.
97

Non-targeted Effects of lonizing Radiation in Fish Cell Lines

O'Neill, Alicia 01 1900 (has links)
<p> This study is one of the first to examine non-targeted effects of radiation in fish cell lines, with the aim of identifying a reliable reporter system for evaluating radiation damage in fish. The ability of the fish cell lines to clone was determined as the clonogenic assay was a major end point used to measure survival. A direct survival curve was completed for all cell lines that were deemed clonogenic using a cobalt-60 γ-radiation source. Non-targeted effects of radiation were evaluated by conducting bystander experiments on all fish cell lines. Delayed Cell Death (DCD) experiments were completed on the fish cell line that showed evidence of a cell death associated bystander effect as these phenomena may be linked. Four of the eight cell lines were found to be clonogenic. The cell line, RTG-2, was found to be the most radiosensitive at lower doses. All of the clonogenic cell lines, with the exception ofRTG-2 cells, generally showed increased Plating Efficiency (P.E.) when Irradiated Cell Conditioned Media (ICCM) was tested on unirradiated autologous cells. ICCM from the clonogenic and non-clonogenic cells was also tested on the mammalian cell line. This resulted in increased cell survival, with the exception of the RTS-pBk+ (p<O.OOl), RTS-34st (p<O.Ol) and ZEB 2J (p<0.05) cell lines. Since RTG-2 showed the most prominent cell killing bystander effect, DCD experiments were performed on this cell line. DCD was found in the progeny of irradiated parental cells at all doses tested. Cell kinetics also showed the generation of possible DCD. The results show that both bystander signal production and cellular responses vary depending on the cell line and that DCD and bystander effects are tentatively linked through genomic instability. The RTG-2 cell line may be a suitable model for a reliable reporter system to aid in determining the nontargeted effects of radiation in fish in the environment. </p> / Thesis / Master of Science (MSc)
98

The biosynthesis of C14- labeled lipids by isolated spermatozoa of man and fish

Minassian, Elaine Shakay January 1965 (has links)
Thesis (M.A.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / The incorporation of C14 label into the lipids of the spermatozoa of man and fish (the alewife, Alosa pseudoharengus,) was studied. Washed spermatozoa of man and the alewife were incubated in vitro under aerobic conditions with glucose-C14 (r.1.). The sperm cells were extracted with chloroform-methanol, and the crude lipid extracts were purified to remove radioactive contaminants. The lipid extracts were fractionated into the major classes of lipids by column chromatography and further separated by thin-layer chromatography. Glycerides, phosphatides and cholesterol were isolated and identified and their radioactivity was determined. C14 label was found exclusively in the lycerol portion of the glycerolipids of the spermatozoa of both man and the alewife. The rates of incorporation of glucose-C14 into the total lipids were 54.4 ummoles/1010 human spermatozoa/hour and 1.8 ummoles/10^10 alewife spermatozoa/hour. In the sperm lipids of both species the glycerides were the most actively labeled components with the diglycerides having the highest specific activities and the triglycerides being the most abundant components. Whereas in human spermatozoa the glyceride content was 20% of the total lipids, in the alewife spermatozoa the fraction constituted only 4% Cholesterol, 14 - 15% of the total sperm lipids in both species, was not labeled. The polyglycerophosphatide fraction was the most abundant and the most actively C14-labeled component in the phosphatides of alewife spermatozoa. Most of the radioactivity incorporated in the phosphatides of human spermatozoa was found in the lecithin and cephalin fractions. Lecithin was the phosphatide of highest specific activity. By means of infrared spectroscopy, evidence of the presence of plasmalogen was found in the phosphatides of human, but not of alewife spermatozoa. Unlike mammalian spermatozoa, fish spermatozoa have poor glycolytic capacity. Nevertheless, the present work shows that fish spermatozoa can utilize glucose for the synthesis of glyceride glycerol at adequate rates. The demonstration of the biosynthesis of lipids from glucose by the spermatozoa of man and fish suggests that sperm may utilize carbohydrate not only for the maintenance of motility through the energy generated by glycolysis, but also for the replenishment of lipid reserves. / 2999-01-01
99

Nutritional and physiological effects of dietary NaCl on rainbow trout (Salmo gairdneri Richardson) and its application in fish culture

Salman, Nadir Abd January 1987 (has links)
No description available.
100

Ecological studies of Antarctic fish with emphasis on early development of inshore stages at South Georgia

North, Anthony William January 1990 (has links)
No description available.

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