Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

PDF

University of Richmond

Development

Theses/Dissertations

Articles 1 - 7 of 7

Full-Text Articles in Entire DC Network

The Exploration Of Novel Symbiotic Bacteria That May Have Influential Roles In Sponge Life History, Brittany E. West Jan 2008

The Exploration Of Novel Symbiotic Bacteria That May Have Influential Roles In Sponge Life History, Brittany E. West

Honors Theses

Sponges produce an impressive variety of secondary metabolites that perform a variety of ecological functions. Many marine sponges even harbor diverse carotenoid compounds, an unusual class of secondary metabolites that animals are incapable of producing. Furthermore, sponges serve as hosts to an astonishingly diverse microbial community that can occupy up to sixty percent of a sponge's biomass. Our research ultimately hopes to link microbial species to the production of secondary compounds, like carotenoids, and to assess the ecological role of such compounds and their effect on sponge life history strategy. This study describes the ecological distribution of two species ...


Intricacies Of Development : The Impact Of Maternal Experience And Isolation On The Social Development Of Juvenile Male Rats, Lillian Maria Christon Aug 2007

Intricacies Of Development : The Impact Of Maternal Experience And Isolation On The Social Development Of Juvenile Male Rats, Lillian Maria Christon

Master's Theses

Reproductive experience induces changes in females. Parity-related differences in maternal treatment of offspring can induce enduring changes in offspring. The relationships between maternal experience, early social isolation, and development were explored in rodents in this experiment. Male rats were weaned from multiparous (MP) and primiparous (PP) mothers and placed into isolation or social housing for four weeks. They were then observed in a social-interaction test. Social behavior and neural oxytocin and vasopressin were assessed post-testing, while corticosterone levels were measured across the four weeks. Weaning was extremely stressful for all offspring. PP- and MP-raised pups exhibited differences in social behavior ...


Figuring The Refugee, Genevieve Goulding Apr 2007

Figuring The Refugee, Genevieve Goulding

Honors Theses

''Figuring the Refugee" explores humanitarian relief for refugees as a discourse; a system of communication and identity-making which creates a subhuman refugee and perpetuates the problems of assistance. Through an auto-ethnographic narrative of my experience in the camp, I consider how the space itself creates exploitative binaries between aid workers and refugees. In an analysis of the United Nations 2006 film appeal, I argue that the discourse is normalized by images of the dehumanized refugee. The rhetoric of the film appeal limits the response of the western viewer to an uncritical sympathy, and allows for ineffective models of refugee assistance ...


Modifications Of Nitric Oxide And Sexual Behavior In Prenatally Stressed Male Rats, Stephen D. Miller Aug 1999

Modifications Of Nitric Oxide And Sexual Behavior In Prenatally Stressed Male Rats, Stephen D. Miller

Master's Theses

Normal male sexual differentiation is the culmination of perfectly timed, prenatal gonadal hormone release. Prenatal stress (PS) has a detrimental effect upon this process, obstructing the natural development of brain structures and sexual behavior. Prenatally-stressed male rats exhibit many physiological and neuroendocrinological differences when compared to control males. PS has a particularly harmful effect upon male sexual behavior, to which the neurotransmitter nitric oxide (NO) has been shown to be intimately involved. The present experiment examined whether PS reduces nNOS, the rate limiting enzyme of NO, in the medial preoptic area (rnPOA) of male rats, and whether administration of the ...


The Effect Of Thyroid Hormone On The Expression Of A7 Myosin Heavy Chain Mrna In Xenopus Laevis, Bradley Thomas Butkovich Aug 1996

The Effect Of Thyroid Hormone On The Expression Of A7 Myosin Heavy Chain Mrna In Xenopus Laevis, Bradley Thomas Butkovich

Master's Theses

It has long been known that thyroid hormone (TH) is responsible for metamorphosis in tadpoles. It is also known that A7 MHC, an adult muscle isoform, is expressed in adult Xenopus laevis frogs, but not in larvae. Furthermore, the appearance of A7 corresponds with the onset of metamorphosis. The present study investigated the relationship between TH and the expression of A7 MHC mRNA in Xenopus laevis. Isolated tails in culture and 6-n-propyl 2-thiouracil (PTU) treated tails were treated with TH and the presence of A7 mRNA analyzed with in-situ hybridization, and RT-PCR. It was found that TH caused substantial regression ...


The Effects Of Thyroid Hormone On Myosin Heavy Chain A-7 Production In Xenopus Laevis Tail And Leg Muscles, Andrew R. Noble Jan 1996

The Effects Of Thyroid Hormone On Myosin Heavy Chain A-7 Production In Xenopus Laevis Tail And Leg Muscles, Andrew R. Noble

Honors Theses

The present research examines the expression of myosin heavy chain genes in muscle fibers in Xenopus laevis. Characteristically different muscle fibers are expressed before and after metamorphosis. The embryonic myosin proteins that are synthesized during the tadpole stages are replaced with adult myosin heavy chains at metamorphosis. At least one of the adult myosin genes, called A-7, is expressed only in the adult animals, not in tadpoles. The controlling factor or trigger for the expression of this adult gene still remains unknown. There are a number of possible explanations for the A-7 regulation at metamorphosis, including changes in particular hormone ...


Some Factors Involved In Growth And Sporulation Of Pilobolus Crystallinus Tode And Pilobolus Umbonatus Buller, Kenneth L. Poff Jun 1964

Some Factors Involved In Growth And Sporulation Of Pilobolus Crystallinus Tode And Pilobolus Umbonatus Buller, Kenneth L. Poff

Master's Theses

Pilobolus umbonatus Buller and P. crystallinus Tode grew normally in a nitrogen atmosphere but their sporagnia were non-pigmented. When palced in anaerobic jars along with obligately anaerobic and obligately aerobic bacteria, the fungi grew in the range of oxygen concentrations too low for growth of the aerobic bacterium, but high enough to prevent growth of the anaerobe. The fungi did not grow when the oxygen was depleted to the point that allowed growth of the anaerobic bacterium. Catalase was not produced by the hyphae and trophocysts which normally grow beneath the surface of the medium, but was present in the ...