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Characterization Of Microsatellite Loci And Pilot Population Genetic Analysis In Hickory Shad, Alosa Mediocris, Fnu Vishakha Aug 2012

Characterization Of Microsatellite Loci And Pilot Population Genetic Analysis In Hickory Shad, Alosa Mediocris, Fnu Vishakha

Theses and Dissertations

The hickory shad (Alosa mediocris) is a relatively understudied species of the anadromous fish sub-family Alosinae. This study, the first population genetic analysis of this species, employed 12 neutral microsatellite loci to estimate genetic diversity and population structure in tributaries of lower Chesapeake Bay, Virginia including James River and its tributaries (Appomattox and Chickahominy Rivers), Rappahannock River, and Pamunkey River. Genetic variation was extremely low. Estimates of observed heterozygosity were lower than expected heterozygosity. Significant population structure was detected among the six samples (FST = 0.093, p = 0.01). Effective population sizes were low (Ne ranged from 2 to 134). …


Ocean Acidification: Understanding The Coastal Carbon Pump In A High Co2 World, Rachel Cooper Aug 2012

Ocean Acidification: Understanding The Coastal Carbon Pump In A High Co2 World, Rachel Cooper

Theses and Dissertations

Since the 1800s, carbon dioxide emissions due to human activities have contributed significantly to the amount of carbon in the atmosphere. Approximately a third of this carbon is absorbed by the ocean, through air-sea fluxes at the ocean surface (Sabine, 2004). Increased CO2 has changed the carbon chemistry of the ocean and hence the pH. pH is expected to drop by 0.4 by the year 2100. It is unclear how this lower pH will affect carbon cycling and sequestration with respect to the biological carbon pump. Most studies have focused on open ocean phytoplankton or bacterial communities in large, stationary …


Effects Of Leaf Litter Diversity On Nutrients And Mosquito Communities In Neotropical Artificial Tree Holes, Rachel Komosinski Jul 2012

Effects Of Leaf Litter Diversity On Nutrients And Mosquito Communities In Neotropical Artificial Tree Holes, Rachel Komosinski

Theses and Dissertations

Inputs from terrestrial habitats to aquatic habitats are important for structuring aquatic communities. Terrestrial producer diversity in the tropics may decline due to anthropogenic causes. I investigated how tree diversity affects aquatic communities. We used leaves from three timber-producing species (Dalbergia retusa, Pachira quinata, and Tectona grandis) to test the effects of leaf litter species composition and richness on invertebrate aquatic communities in Gamboa, Panama. We quantified macroinvertbrate species richness and abundances, leaf litter mass loss, and dissolved carbon to nitrogen ratios (C:N) after 4 weeks. We found that litter types differed in breakdown and C:N. Tectona grandis had lower …


Sex-Specific Habitat Use And Responses To Fragmentation In An Endemic Chameleon Fauna, Philip Shirk Jul 2012

Sex-Specific Habitat Use And Responses To Fragmentation In An Endemic Chameleon Fauna, Philip Shirk

Theses and Dissertations

Chameleons are an understudied taxon facing many threats, including collection for the international pet trade and habitat loss and fragmentation. A recent field study reports a highly female-biased sex ratio in the Eastern Arc Endemic Usambara three horned chameleon, Trioceros deremensis, a large, sexually dimorphic species. This species is collected for the pet trade, and local collectors report males bring a higher price because only this sex has horns. Thus, sex ratios may vary due to differential rates of survival or harvesting. Alternatively, they may simply appear to be skewed if differences in habitat use biases detection of the sexes. …


The Role Of A And B Vitamins During Orofacial Development Of Xenopus Laevis, Allyson Kennedy Jun 2012

The Role Of A And B Vitamins During Orofacial Development Of Xenopus Laevis, Allyson Kennedy

Theses and Dissertations

Orofacial anomalies make up about a third of the 120,000 birth defects each year in the United States. Children born with these abnormalities must undergo immense physical and emotional strain in order to correct the defects. In fact, about $697 million is spent every year surgically treating children with cleft lip and/or cleft palate (2011). In countries where surgery is not an option, this abnormality causes immense difficulties in eating, hearing, speech, and psychosocial development. The causes of cleft lip/palate are extremely complex. Genetics play a role in the anomaly; however, 95% of cleft palate cases are non-syndromic and likely …


Impacts Of Rdx Soil Contamination Across An Age Gradient For The Native Shrub Morella Cerifera., Stephen Via May 2012

Impacts Of Rdx Soil Contamination Across An Age Gradient For The Native Shrub Morella Cerifera., Stephen Via

Theses and Dissertations

Understanding the impacts of explosive contamination on vegetation is key to understanding explosives behavior in the environment. I quantified shrub growth responses to 1,3,5-trinitroperhydro-1,35-triazine (RDX) soil contamination across three life stages and I hypothesized that RDX would have the greatest impact on seed germination. Morella cerifera seeds were germinated on soils amended with RDX up to 1500 mg RDX kg-1 dry soil. Juvenile and adult individuals were exposed for 6 weeks to soil amended with RDX up to 750 and 1500 mg RDX kg-1 dry soil, respectively. Morphological responses were quantified for juveniles while physiological measurements were quantified for adults. …


Functional And Biochemical Consequences Of Single Nucleotide Polymorphisms In The Human Vesicular Monoamine Transporter 1 Gene (Slc18a1) By Sally Gamal Shukry, B.S., Sally Gamal Shukry May 2012

Functional And Biochemical Consequences Of Single Nucleotide Polymorphisms In The Human Vesicular Monoamine Transporter 1 Gene (Slc18a1) By Sally Gamal Shukry, B.S., Sally Gamal Shukry

Theses and Dissertations

Abstract FUNCTIONAL AND BIOCHEMICAL CONSEQUENCES OF SINGLE NUCLEOTIDE POLYMORPHISMS IN THE HUMAN VESICULAR MONOAMINE TRANSPORTER 1 GENE (SLC18A1) By Sally Gamal Shukry, B.S. A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Biology at Virginia Commonwealth University. Virginia Commonwealth University, 2012 Major Advisor: Jennifer K. Stewart Associate Professor and Graduate Director, Department of Biology Single nucleotide polymorphisms (SNP) in the human VMAT1 gene (SLC18A1) have been associated with schizophrenia in three different populations: Han Chinese, Western European and Japanese. Effects of these mutations on transport function of the hVMAT1 protein have not …


Assessing The Genotoxicity Of Triclosan In Tadpoles Of The American Bullfrog, Lithobates Catesbeianus., David Emery Apr 2012

Assessing The Genotoxicity Of Triclosan In Tadpoles Of The American Bullfrog, Lithobates Catesbeianus., David Emery

Theses and Dissertations

Amphibians are particularly sensitive to environmental degradation and, therefore, serve as effective environmental quality indicators. Research has suggested that amphibian declines are exacerbated by manmade environmental toxicants, especially those found in high concentrations in urban areas. The NIH has pinpointed genotoxicity as a major route of cancer causation, and has since developed stringent testing procedures for potentially hazardous chemicals. One such method, recognized for its simplicity and economy, is the micronucleus assay. A study was conducted assessing the genotoxicity of the widely used antimicrobial agent Triclosan to American Bullfrog tadpoles. Lithobates catesbeianus tadpoles were reared in glass aquaria containing ultra-high …


Adam10: A Novel Regulator Of Mast Cell Function And Activation, Travis Faber Jan 2012

Adam10: A Novel Regulator Of Mast Cell Function And Activation, Travis Faber

Theses and Dissertations

In this study we show, to our knowledge, the first description of the role ADAM10 plays on mast cells. ADAM10 is abundantly expressed on mast cells both in vitro and in vivo. Its expression is inhibited by IL-10, a suppressive cytokine. siRNA depletion of ADAM10 on bone marrow-derived mast cells (BMMC) caused decreased IL-6 production following IgE cross-linking and also impaired BMMC stem cell factor (SCF)-induced migration through collagen IV. Mast cells and T helper cells (Th cells) in the peritoneum were reduced in ADAM10 KO mice. In addition, ADAM10 KO BMMC produced significantly less of all cytokines measured following …