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Full-Text Articles in Physical Sciences and Mathematics

Predation On Juvenile Blue Crabs, Callinectes Sapidus Rathbun, In Lower Chesapeake Bay: Patterns, Predators, And Potential Impacts, Kirt E. Moody Jan 1994

Predation On Juvenile Blue Crabs, Callinectes Sapidus Rathbun, In Lower Chesapeake Bay: Patterns, Predators, And Potential Impacts, Kirt E. Moody

Dissertations, Theses, and Masters Projects

Various investigations of the population dynamics of blue crabs in Chesapeake Bay indicate that predator-induced mortality in the juvenile phase may determine year-class strength. In a tethering study, which spanned three seasons in shallow-water habitats of the lower York River, daily mortality rates of juvenile crabs were measured across three variables: crab size (30-70 mm carapace width), habitat type (seagrass, mud, and sand), and month (May-November). Vulnerability to predation was consistently lower for larger crabs, approaching a size refuge from predation at approximately 90 mm carapace width. Predation was most intense in unvegetated sand habitats, and significantly lower in seagrass …


The Synthesis Of 5-Benzoyl-1,3-Benzendediacids For The Double-Capping Of Beta-Cyclodextrin, Daniel Macdougall Williams Jan 1994

The Synthesis Of 5-Benzoyl-1,3-Benzendediacids For The Double-Capping Of Beta-Cyclodextrin, Daniel Macdougall Williams

Dissertations, Theses, and Masters Projects

No abstract provided.


Direct Determination Of Trace Metals In Saline Water Samples Using Gfaas, Michael Joseph Wassell Jan 1994

Direct Determination Of Trace Metals In Saline Water Samples Using Gfaas, Michael Joseph Wassell

Dissertations, Theses, and Masters Projects

No abstract provided.


Muon Transfer From Muonic Deuterium To Carbon, David William Viel Jan 1994

Muon Transfer From Muonic Deuterium To Carbon, David William Viel

Dissertations, Theses, and Masters Projects

Negative muons were brought to rest in a gas mixture of 30 torr CH$\sb4$ and 570 torr D$\sb2$, using the cyclotron trap at PSI. The muons formed muonic deuterium atoms which diffused through the mixture and transferred their muons to the carbon of the CH$\sb4$ molecules. A planar germanium detector and a silicon detector were used to observe x-rays from the initial muon cascade in the deuterium, and from subsequent cascade in the muonic carbon after transfer. A transfer rate of (4.5 $\pm$ 1.8) $\times$ 10$\sp{10}$/sec was found which agrees well with a previous result measured at 50 bar of …


The Requirements Of Patentability As Applied To The Chemical Arts, Joy L. Bryant Jan 1994

The Requirements Of Patentability As Applied To The Chemical Arts, Joy L. Bryant

Dissertations, Theses, and Masters Projects

No abstract provided.


Size-Specific Fecundity Of The Sea Scallop, Placopecten Magellanicus, During One Spawning Period In The Mid-Atlantic Resource Area, Ryan B. Carnegie Jan 1994

Size-Specific Fecundity Of The Sea Scallop, Placopecten Magellanicus, During One Spawning Period In The Mid-Atlantic Resource Area, Ryan B. Carnegie

Dissertations, Theses, and Masters Projects

No abstract provided.


Alternative Management Programs Within The Atlantic Sea Scallop Placopecten Magellanicus Fishery: Property Rights, Transferable Quotas And Fishing Effort, Niels E. Moore Jan 1994

Alternative Management Programs Within The Atlantic Sea Scallop Placopecten Magellanicus Fishery: Property Rights, Transferable Quotas And Fishing Effort, Niels E. Moore

Dissertations, Theses, and Masters Projects

No abstract provided.


Investigations Into Cataract Formation In Sciaenid Fish Species From The Elizabeth River, Chesapeake Bay, Virginia, Christopher D. Williams Jan 1994

Investigations Into Cataract Formation In Sciaenid Fish Species From The Elizabeth River, Chesapeake Bay, Virginia, Christopher D. Williams

Dissertations, Theses, and Masters Projects

Cataract formation in the Elizabeth River (ER) has been reported since 1986. Previous studies have concentrated on describing cataract as a function of exposure to polluted sediments, especially polycyclic aromatic hydrocarbons (PAH). These studies, however, have not examined what processes might be involved in fish cataractogenesis. The overall objective of this research was to identify important processes associated with the early development of cataract in feral fish populations. Field studies were used to systematically examine cataract development. Cataract in sciaenids was not associated with previously described cataractogenic factors, but could be linked to contaminated sediments of the ER. Cataract was …


Effects Of Methyl Parathion On The Cellular Immune Responses In Giant Black Tiger Shrimp, Penaeus Monodon, Nantarika. Bodhipaksha Jan 1994

Effects Of Methyl Parathion On The Cellular Immune Responses In Giant Black Tiger Shrimp, Penaeus Monodon, Nantarika. Bodhipaksha

Dissertations, Theses, and Masters Projects

The effects of an organophosphorus pesticide, methyl parathion, on cellular immune defense mechanisms of the giant black tiger shrimp (Penaeus monodon) were studied. Animals were exposed for 96 hours at concentrations equal to, above and below the LC&\sb{lcub}50{rcub}& (3 ppb). Phagocytes were obtained from the heart and circulating hemolymph. Cellular immune responses, including chemotaxis, phagocytosis and the respiratory burst were examined. Chemotactic activity was determined by means of a modified Boyden double chamber technique. There was a dose-dependent decrease in the chemotactic activities of both circulating hemocytes and cardiac phagocytes. Phagocytic activity (percent phagocytosis) was examined by the microscopic enumeration …