Life Sciences Commons^™

Evidence For The Sensory Receptor(S) Of The Mounting Sex Pheromone In Two Species Of Ixodid Ticks, Dermacentor Variabilis (Say) And Dermacentor Andersoni Stiles, James Stephen Phillips

Biological Sciences Theses & Dissertations

The foreleg claw sensilla were determined to be the receptors of the female contact sex pheromone, MSP (mounting sex pheromone), in D. variabilis, D. andersoni and A. americanum male ticks. In all three tick species, the claw sensilla consists of six anteriorly-directed setae arranged in three symmetrical pairs, two each on the opposite sides of the apotele of the claw and one on the ventral side. Behavioral bioassays and morphological study of these setae revealed that only the dorsal and middle (= lateral) pairs of claw sensilla are mechanogustatory, while the ventral pair are strictly mechanoreceptors. The dorsal and …

Retention Of Cellular Viability And Growth Potential In Cryopreserved Bovine Arterial Tissue: Implications For Clinical Use Of Cryopreserved Vascular Allografts, Kip G. Gardner

Biological Sciences Theses & Dissertations

Segments of bovine calf aortas and pulmonary arteries were cryopreserved at -196° C for two weeks to 18 months and subsequently thawed. Cellular morphology, viability, and growth potential in these segments were then compared with the same attributes in segments from fresh (control) arteries. Scanning electron microscopy revealed no disruption of intimal surfaces attributable to cryopreservation. Endothelial cells were successfully cultured from all cryopreserved arterial segments. Endothelial monolayers grown from cryopreserved arteries had a cobblestone appearance and expressed Factor VIII antigen but not smooth muscle alpha-actin. Plating efficiency in primary cultures of endothelial cells was lower for cryopreserved arteries than …

A Multivariate Characterization Of Assemblages Of Planktonic Mysids Decapods And Sergestids In The Chesapeake Bay Mouth Area, John Charles Seibel

Biological Sciences Theses & Dissertations

This study is the first to focus on the assemblages of the planktonic mysids, decapods, and sergestids found in the lower Chesapeake Bay. The assemblages of these organisms in the lower Chesapeake Bay and nearby shelf were characterized using three different statistical approaches, and the methods used were evaluated for their effectiveness at delineating ecologically meaningful assemblages. Three stations were sampled across the Chesapeake mouth and one offshore, with oblique and neuston net tows. Twenty-seven larval stages, representing at least 23 species, were found in sufficient numbers to be analyzed statistically. The statistical approaches were each based upon a different …

Differential Utilization Of Allochthonous And Autochthonous Carbon By Aquatic Insects Of Two Shrub-Steppe Desert Spring-Streams: A Stable Carbon Isotope Analysis And Critique Of The Method, Alfred Lynn Mize

Biological Sciences Theses & Dissertations

Stable carbon isotope analysis, a technique that measures the ratio of stable carbon-12 to stable carbon-13 in abiotic and biotic components of ecosystems, was used to assess the differential utilization of autochthonous and allochthonous carbon by aquatic insects of two cold desert spring-streams in the Columbia Basin of Washington State. The aquatic insects of Snively Springs, a heavily overgrown and densely shaded stream, has isotopic values close to that of stream aufwuchs (substrata scrubate) indicating substantial autochthonous carbon dependence. Aquatic insects of Douglas Creek, the more open and less shaded of the two streams, were equally dependent upon autochthonous and …

Seasonal Changes In Brown Adipose Tissue And Pelage Of The Southern Short-Tailed Shrew Blarina Carolinensis, Elisa Michelle Dew

Biological Sciences Theses & Dissertations

Winter survival mechanisms in the southern short-tailed shrew, Blarina carolinensis, were studied by examining cellular changes in interscapular brown adipose tissue (ISBAT) and pelage characteristics in specimens collected each month of the year in eastern Virginia. On capture, each specimen was anesthetized with ether and then perfused with a 2.5% glutaraldehyde-2% formaldehyde solution. ISBAT tissues were examined histologically with the transmission electron microscopy. Because BAT is know to produce heat by nonshivering thermogenesis and is more developed in winter animals than summer animals, it was hypothesized that mitochondrial area of BAT would be relatively greater in winter than in summer. …

Mat Movement In Coastal Louisiana Marshes: Effect Of Salinity And Inundation On Vegetation And Nutrient Levels, Christopher Martin Swarzenski

Biological Sciences Theses & Dissertations

The present research compared and contrasted the physical structure of floating and rooted marshes, their differing responses to open-water salinities and inundation, as well as the nutrient distribution in the porewaters and sediment. The effects of the physical differences in the two marsh types on the ocurrence of the dominant emergent vegetation was discussed.

The main difference in physical structure of the two marsh types was the presence of a mineral, non-buoyant layer at 25-45 cm depth in the rooted marsh, which could serve as an anchor for the overlying highly organic mat layer found in both marsh types. Porewater …

The Functional Role Of Peripheral Nerves In Ige-Mediated Inflammation, Gary Wright Miller

Biological Sciences Theses & Dissertations

IgE-mediated inflammation was measured in mouse footpads with and without sciatic innervation. Mice were passively sensitized with IgE anti-dinitrophenol, a monoclonal antibody. Antigen-induced swelling was reduced by 26% by sciatic nerve transection. Whether transection occurred 10 days prior or immediately prior to antigen challenge did not affect the swelling response. The full inflammatory response was restored by antidromic stimulation of the distal portion of the cut nerve, but only in the freshly cut nerve. Antigen-induced swelling was unaffected by rhizotomy or spinal nerve transection. Pre-treatment with capsaicin reduced the swelling to a level similar to sciatic nerve transection. Treatment with …

Biodegradation Of Crude Oil By Marine Higher Fungi, Brian J. Dyer

Biological Sciences Theses & Dissertations

Four experiments were performed to determine the ability of marine higher fungi to grow in and degrade crude oil. Eight species, previously determined to be hydrocarbonoclastic, were grown in artificial sea water medium (ASM) and southern Louisiana crude oil. The dry mycelial weights were measured and consumption of crude oil was measured gravimetrically. The two species with the best growth, Corollospora maritima and Zalerion maritimum, were grown in ASM containing crude oil spiked with three known hydrocarbons. To this was added glucose (0.15%) and incubated 49 days to test for possible cometabolism of hydrocarbons. Hydrocarbons remaining in the growth …