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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.
41

Growth and population evaluation of walleye (Sander vitreus mitchill) using scales and otoliths as the aging structure in Norfork Lake and Bull Shoals Lake /

Canter, Stephen Christopher, January 1900 (has links)
Thesis (M.S.)--Missouri State University, 2009. / "May 2009." Includes bibliographical references (leaves 35-37). Also available online.
42

Development of a standard weight equation for juvenile steelhead trout and effects of temperature, turbidity, and steelhead trout biomass on relative weight /

McLaughlin, Katherine D. January 1900 (has links)
Thesis (M.S.)--Humboldt State University, 2009. / Includes bibliographical references (leaves 49-57). Also available via Humboldt Digital Scholar.
43

Headspace aroma components in raw and cooked salted-dried fishes and the effects of fish types, preparation methods and locations of purchase on the compositions of the headspace components.

January 2005 (has links)
Yeung Chi-wang. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 128-144). / Abstracts in English and Chinese. / Abstract (in English) --- p.i / Abstract (in Chinese) --- p.iv / Acknowledgement --- p.vi / Contents --- p.vii / List of Figures --- p.xi / List of Tables --- p.xiii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Literature review --- p.3 / Chapter 2.1 --- Nutritional facts of fish --- p.3 / Chapter 2.2 --- Aroma of fish --- p.5 / Chapter 2.2.1 --- Carbonyls and alcohols --- p.6 / Chapter 2.2.2 --- Sulphur-containing compounds --- p.7 / Chapter 2.2.3 --- Bromophenols --- p.9 / Chapter 2.2.4 --- Hydrocarbons --- p.9 / Chapter 2.2.5 --- Off flavor in fish --- p.9 / Chapter 2.2.6 --- Autoxidation of fish meat --- p.10 / Chapter 2.2.7 --- (Z)-4-heptenal in cooked and stored fish --- p.10 / Chapter 2.2.8 --- Volatile acids --- p.11 / Chapter 2.3 --- Salted-dried fish in Hong Kong --- p.11 / Chapter 2.3.1 --- Salted-dried fish used in this study --- p.13 / Chapter 2.3.2 --- Salting methods of the salted-dried fish used in this study --- p.14 / Chapter 2.3.3 --- Salting method used in Tai O --- p.15 / Chapter 2.4 --- Aroma analysis --- p.19 / Chapter 2.4.1 --- Extraction methods --- p.19 / Chapter 2.4.1.1 --- Steam distillation methods --- p.20 / Chapter 2.4.1.2 --- Solvent extraction methods --- p.22 / Chapter 2.4.1.3 --- Headspace methods --- p.22 / Chapter 2.4.2 --- Screening of important aroma contributing volatile compounds --- p.23 / Chapter 2.5 --- Overview --- p.26 / Chapter Chapter 3 --- Method Development --- p.28 / Chapter 3.1 --- Introduction --- p.28 / Chapter 3.2 --- Methodology --- p.29 / Chapter 3.2.1 --- Reproducibility of injection mode --- p.29 / Chapter 3.2.2 --- Optimization of the sample preparation procedure --- p.29 / Chapter 3.2.3 --- Gas chromatography-mass spectrometry coupled with cooled injection system (GC-MS-CIS) --- p.30 / Chapter 3.3 --- Results and discussion --- p.31 / Chapter 3.3.1 --- Reproducibility of the cooled injection system --- p.31 / Chapter 3.3.2 --- Efficiency of different injection modes --- p.33 / Chapter 3.3.3 --- Optimal equilibrium Time --- p.33 / Chapter 3.3.4 --- Conclusion --- p.37 / Chapter Chapter 4 --- Volatile compounds in the headspace of salted-dried fish --- p.38 / Chapter 4.1 --- Introduction --- p.38 / Chapter 4.2 --- Materials and Methods --- p.39 / Chapter 4.2.1 --- Sample preparation --- p.39 / Chapter 4.2.2 --- Headspace analysis and gas chromatography-mass spectrometry (GC-MS) --- p.42 / Chapter 4.2.3 --- "Identification, quantification and odor activity values (OAV) of compounds" --- p.43 / Chapter 4.2.4 --- Statistical analysis --- p.44 / Chapter 4.3 --- Results and discussion --- p.45 / Chapter 4.3.1 --- Headspace profiles of three salted-dried fishes in Hong Kong --- p.45 / Chapter 4.3.1.1 --- Aldehydes and alcohols --- p.63 / Chapter 4.3.1.2 --- Hydrocarbons and ketones --- p.66 / Chapter 4.3.1.3 --- Nitrogen- (N-)containing and sulfur- (S-)containing compounds --- p.68 / Chapter 4.3.1.4 --- "Esters, furans and pyrazines" --- p.72 / Chapter 4.3.1.5 --- "Acids, pyrroles and pyridine" --- p.73 / Chapter 4.3.1.6 --- Important aroma contributing compounds in salted-dried fish --- p.74 / Chapter 4.3.2 --- Influence of steaming on the salted-dried fish headspace --- p.75 / Chapter 4.3.3 --- Difference in the headspace of salted-dried fish purchased between the first and second year --- p.76 / Chapter 4.3.4 --- Influence of salting methods on the salted-dried fish aroma --- p.76 / Chapter 4.3.5 --- Difference between salted-dried fish purchased at Sai Wan and Tai O --- p.78 / Chapter 4.3.6 --- Difference between salted-dried fish produced from difference fish species --- p.78 / Chapter 4.4 --- Conclusion --- p.79 / Chapter Chapter 5 --- Aroma active compounds in salted-dried fish --- p.81 / Chapter 5.1 --- Introduction --- p.81 / Chapter 5.2 --- Materials and Methods --- p.82 / Chapter 5.2.1 --- Sample preparation --- p.82 / Chapter 5.2.2 --- Gas chromatography static headspace analysis and olfactometry GC-SHA-O and aroma extract dilution analysis (AEDA) --- p.84 / Chapter 5.2.3 --- Compound identification --- p.85 / Chapter 5.2.4 --- Calculation of flavor dilution (FD) factor --- p.85 / Chapter 5.3 --- Results and discussion --- p.86 / Chapter 5.3.1 --- Aroma active compounds in salted-dried fish --- p.86 / Chapter 5.3.1.1 --- Strong and Potent aromas --- p.87 / Chapter 5.3.1.2 --- Roasted aromatic aromas --- p.94 / Chapter 5.3.1.3 --- Floral aromas --- p.95 / Chapter 5.3.1.4 --- Vegetative aromas --- p.96 / Chapter 5.3.1.5 --- Penetrating aromas --- p.97 / Chapter 5.3.1.6 --- Common aromas --- p.98 / Chapter 5.3.2 --- Characteristic of aroma active compounds between steamed and non-steamed salted-dried fish --- p.99 / Chapter 5.3.3 --- Differences in aroma active compounds between regular and delayed salted-dried fish --- p.100 / Chapter 5.3.4 --- Characteristic aroma of different species of salted-dried fish --- p.105 / Chapter 5.3.5 --- Characteristic aroma of salted-dried fish purchased at Sai Wan and Tai O --- p.108 / Chapter 5.3.6 --- Characteristic aroma of salted-dried fish purchased in 2001 and 2002 --- p.108 / Chapter 5.4 --- Conclusion --- p.108 / Chapter Chapter 6 --- Important volatile compounds in salted-dried fish --- p.112 / Chapter 6.1 --- Comparison between OAV and SHA-O --- p.112 / Chapter 6.2 --- Overall conclusion --- p.114 / Chapter 6.2.1 --- Effects of steaming on salted-dried fish aroma --- p.114 / Chapter 6.2.2 --- Effects of salting methods on salted-dried fish aroma --- p.117 / Chapter 6.2.3 --- Characteristics aroma of salted-dried fish prepared from different fish species --- p.120 / Chapter 6.2.4 --- Characteristics aroma of salted-dried fish purchased from different locations --- p.120 / Chapter 6.2.5 --- Characteristics aroma of salted-dried fish purchased from different periods --- p.125 / References --- p.128 / Appendix --- p.145
44

Age, growth and maturity of the longnose skate (Raja rhina) for the U.S. west coast and sensitivity to fishing impacts

Thompson, Josie E. 06 September 2005 (has links)
In the past, sharks, skates and ray species have mainly occurred in incidental fisheries. Now they are increasingly being directly targeted due to the depleted status of traditionally targeted species. The life history characteristics of many elasmobranch species make them more sensitive to high rates of fishing mortality. The combination of these factors has resulted in the known local depletion of several elasmobranch species; including the barndoor skate, Raja laevis, of the Northwest Atlantic and the common skate, Raja batis, of Irish Sea. The longnose skate, Raja rhina, occurs commonly as incidental catch in trawl fisheries off the coast of California, Oregon and Washington. Commercial landings of skates, including R. rhina, have increased dramatically along the U.S. West coast. The objectives of this study have been to calculate accurate growth and maturity parameters for Raja rhina in order that the vulnerability of this species to fishing mortality can be assessed. The slow growth rates (k=0.04 to 0.06) and late ages-at-50% maturity (11 to 16 years with maximum ages between 15 and 22 years, depending on sex and region) which were calculated indicate that this species may be at great risk of depletion in the future. Survey biomass trends indicate that R. rhina populations have remained stable over the past twenty years. However, the possibility that biomass levels in the distant past were much higher than they are at present cannot be ruled out. It is recommended that the collection of fishery-dependent data for this species and other skate species begins immediately. This information, along with the results found in this are needed for a proper assessment for Raja rhina, so that the effects of current fishing pressures can be evaluated and regulated appropriately. / Graduation date: 2006
45

Effects of acute stress and exercise on subsequent seawater adaptation and cortisol dynamics in juvenile steelhead trout (Oncorhynchus mykiss)

Liebert, Anja M. 05 February 2004 (has links)
The present study investigated the effects of stress and exercise on seawater (SW) adaptation and cortisol dynamics in juvenile steelhead (Oncorhynchus mykiss). To examine the effects of stress, fish acclimated to freshwater (FW) were subjected for 3 hours to confinement stress in FW, and subsequently SW (25 ppt) was introduced to all tanks. Fish were sampled immediately after the stress treatment, and 1, 7, and 14 days after introduction of SW. Electrolytes, cortisol, glucose and lactate followed the typical pattern that we expected after stress treatment in FW. Fish regained osmotic balance within 24 hours. Glucose concentrations were increasing throughout the experiment and lactate levels stayed elevated during the time spent in SW. IGF-1 did not show an immediate response to stress but after transfer to SW we detected significantly higher concentrations for control fish at days 1 and 14. The differences in IGF-1 levels between stressed and control fish are not reflected in SW adaptability but positive correlations between IGF-1 and electrolyte levels in control fish may indicate its role for osmoregulation. Confinement stress did not impair feed intake subsequently in SW, but our results suggest that feed intake was suppressed by the change of the media from FW to SW. The second study investigated the effects of exercise treatment in FW on SW adaptation and cortisol dynamics in juvenile steelhead. Plasma cortisol and in vitro cortisol secretion by interrenal cells after a 24 hr SW challenge test were neither affected by moderate exercise nor by water temperature (13��C, 21��C), however, plasma osmolality was lower in exercised fish compared to unexercised fish. Half-life (T[subscript 1/2]) of ��H-cortisol was shorter in fish exposed to exercise whereas metabolic clearance rate (MCR) did not respond to exercise treatment. Uptake and retention of corticosteroids in liver and gall bladder were enhanced in exercised fish, and retention of corticosteroids in muscle tissue was longer in unexercised fish. Our findings suggest that exercise likely decreases stress levels in fish and improves the adaptation to seawater (SW) in juvenile steelhead. / Graduation date: 2004
46

A case study of factors impacting on marketing of South African fish oil in the animal feed market /

Stefanus, Titania Vaida. January 1900 (has links)
Thesis (MTech (Business Administration))--Peninsula Technikon, 2002. / Word processed copy. Summary in English. Includes bibliographical references (leaves 80-82). Also available online.
47

Development of a progeny marker for steelhead /

Shippentower, Gene E. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 39-42). Also available on the World Wide Web.
48

Habitat requirements and foraging ecology of the Madagascar fish-eagle /

Berkelman, James, January 1997 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1997. / Title from PDF title page (viewed on Apr. 2, 2005). Vita. Includes bibliographical references (p. 57-68).
49

A Bayesian network for prioritizing restoration of aquatic connectivity /

Andersen, Eric J. (Eric John). January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2011. / Printout. Includes bibliographical references (leaves 60-67). Also available on the World Wide Web.
50

The mating system of steelhead and the effect of length and arrival date on steelhead reproductive success /

Seamons, Todd R. January 2005 (has links)
Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (leaves 168-178).

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