Life Sciences Commons^™

Bacterial Degradation Of Disinfection By-Products In Drinking Water, Laura Inga Fauntleroy

Chemistry & Biochemistry Theses & Dissertations

Chlorine became a major disinfectant for the removal of microbial contaminants in 1914. Current water chlorination procedures yield halogenated disinfection byproducts (DBPs), such as haloalkanes and haloacetic acids (HAAs), due to the reaction of chlorine with naturally occurring organic compounds. Various water utilities have observed decreased HAAs levels in maximum residence time locations (MRTLs), where they were expected to be higher. These MRTLs have low free chlorine residual and high heterotrophic bacteria plate counts. Xanthobacter autotrophicus, GJ-10, is a bacterium that has been shown to contain dehalogenase enzymes and, therefore, can biodegrade HAAs. A number of water-system bacteria were …

Strong Interactions Between Juvenile Caribbean Spiny Lobster (Panulirus Argus) And Caribbean Reef Octopus (Octopus Briareus) In The Florida Keys, Jennifer Anne Lear

Biological Sciences Theses & Dissertations

Coexisting species may simultaneously compete for resources and interact as predator and prey, creating a strong interaction that can alter the structure of animal communities. This type of interaction potentially occurs between juvenile Caribbean spiny lobster (Panulirus argus) and Caribbean reef octopus (Octopus briareus) within hard-bottom habitats in the Florida Keys, FL (USA), where octopuses may consume juvenile lobsters and also compete with them for limited crevice shelters. I conducted a series of field and mesocosm studies to investigate the nature of octopus-lobster interactions and their implications for the structure of their populations in the wild. …

A Staging Sequence And Analysis Of Growth In Postovipositional Embryos Of Lamprophis Fulignosus, Angela Renee Vogel Rivera

Biological Sciences Theses & Dissertations

The brown house snake, Lamprophis fuliginosus, is a small, oviparous snake found throughout much of Africa. This lamprophiine colubrid reproduces rapidly; captive females can lay clutches every three to four months for a sustained period. Thus, L. fuliginosus is an excellent model for developmental studies requiring large numbers of embryos. In addition, the embryos of oviparous species are more suitable for some procedures than are those of viviparous forms. The most widely used system for staging embryonic snakes was developed for the common gartersnake, Thamnophis sirtalis, a viviparous natricine colubrid (Zehr, 1962). Based on the examination of 135 …

Energy-Landscape-Model Analysis For Irreversibility And Its Pulse-Width Dependence In Cells Subjected To A High-Intensity Ultrashort Electric Pulse, R. P. Joshi, Q. Hu, Karl H. Schoenbach, Stephen J. Beebe

Bioelectrics Publications

We provide a simple, but physical analysis for cell irreversibility and apoptosis in response to an ultrashort (nanosecond), high-intensity electric pulse. Our approach is based on an energy landscape model for determining the temporal evolution of the configurational probability function p(q). The primary focus is on obtaining qualitative predictions of a pulse width dependence to apoptotic cell irreversibility that has been observed experimentally. The analysis couples a distributed electrical model for current flow with the Smoluchowski equation to provide self-consistent, time-dependent transmembrane voltages. The model captures the essence of the experimentally observed pulse-width dependence, and provides a possible physical picture …

The Ultrastructure Of The Olfactory System In Two Species Of Short-Tailed Shrews, Blarina Brevicauda And Blarina Carolinensis, Lisa Johnson Byrum

Theses and Dissertations in Biomedical Sciences

Several studies of the fine structure of the olfactory system of rodents have been conducted, but very little research has been done on members of the Insectivora. The olfactory systems of the northern short-tailed shrew, Blarina brevicauda, and the southern short-tailed shrew, Blarina carolinensis, were examined by light and electron microscopy. These shrews were live trapped in the vicinity of Norfolk, Virginia throughout all months of the year. Olfactory tissues were processed following standard transmission and scanning electron microscopy protocols. The olfactory system structures investigated included the olfactory epitheliumlmucosa (OEM), main olfactory bulb (MOB), accessory olfactory bulb (AOB), …

Recently Elected Fellows

Virginia Journal of Science

The Virginia Academy of Science elected three scientists at the 2004 Banquet: Harold G Marshall, Rosemary Barra, and Arthur F. Conway.

Comparative Systematics Of Subterranean Amphipod Crustaceans (Hadzioidea), Thomas R. Sawicki

Biological Sciences Theses & Dissertations

The research project presented in this doctoral dissertation is a compilation of six published papers. Therefore, instead of being a single comprehensive project, it is composed of a number of sub-projects. Introductory and summary sections provide structure for the compilation of papers.

The research for this dissertation investigates the systematics of genera within the amphipod families Hadziidae Karaman, 1943 and Melitidae Bousfield, 1973. In the family Hadziidae, Bahadzia patilarga is described from an anchialine cave on the southern coast of Cuba, B. caymanensis is described from a weakly brackish-water pool in a small cave on Grand Cayman Island in the …

The Effects Of Ankle Taping And Spatting On The Reaction Times Of The Supporting Musculature Of The Ankle Before And After Exercise In Healthy And Functionally Unstable Ankles, Jennifer I. Mckenzie

Human Movement Studies & Special Education Theses & Dissertations

Ankle taping is a common practice in the athletic training room, but there is minimal evidence to support its effectiveness in enhancing muscle activation. The purpose of this study was to examine the effects of ankle taping on muscle activation following sudden inversion in functionally unstable and healthy ankles before and after exercise. Fourteen recreational athletes with a unilateral functionally unstable ankle volunteered to participate. Surface EMG electrodes were placed on the peroneals and anterior tibialis muscles of both extremities. Each subject received four treatment conditions; ankle taping, ankle taping with spatting, spatting, and no tape in a randomly assigned, …

Effect Of Cycling Cadence On Economy At High Power, Carol Beatriz Ennser

Human Movement Studies & Special Education Theses & Dissertations

This study was designed to determine the most economical cadence for cyclists at high power outputs (> 300 W). Six cyclists and two triathletes (age 31.5 ± 8.8 yr, mass 76.9 ± 8.6 kg, VO₂max 4.84 ± 0.36 Lmin^·1, weekly training 318 ± 118 km) who were capable of riding a bicycle at a speed of 40 kph for 10 min (solo) participated in five tests on a bicycle ergometer. The preliminary test measured subjects' VO₂max. After that, subjects completed four trials, each at a predetermined cadence as follows: 60, 80, 100 and 120 …

An Assessment Of High School Coaches Knowledge Of Exercise-Induced Asthma, Shannon L. Wilson

Human Movement Studies & Special Education Theses & Dissertations

Exercise-induced asthma (EIA) is a common disorder that occurs in individuals who compete in recreational activities. The purpose of this study was to determine the knowledge of EIA for high school athletic coaches. A 22 question demographic instrument was used for background information, and an 18 question multiple-choice assessment was used to assess knowledge of prevention, recognition and management of EIA. A panel of experts reviewed and modified the survey instruments, which were piloted at a local private high school prior to distribution. The survey was distributed to 250 high school coaches in the Hampton Roads area during a fall …

The Effects Of Plyometrics Training On Neuromuscular Responses And Ground Reaction Forces Surrounding The Knee, Barbara Mcdowell

Human Movement Studies & Special Education Theses & Dissertations

Several investigations have noted altered kinetic and neuromuscular landing patterns in adolescent female athletes following various plyometrics programs. The purpose of this study was to investigate the effects of a time-limited plyometrics training program on neuromuscular responses and peak vertical ground reaction force (PVGRF) in Division I collegiate soccer players. Sixteen (8 male, age=l9.38 ± 1.4 yrs, ht= 178.44 ± 8.99 cm, mass =80.38 ± 8.37 kg; 8 female, age=19.75 ± 0.71 yrs, ht=163.83 ± 4.30 cm, mass =62.13 ± 6.29 kg) athletes completed the testing protocol and plyometric training. Seven (3 male, average age=22.00 ± 1.00 yrs, average height=171.88 …

Seed Bank Response To Fire And Successional Trajectory Of A Virginia Small Depression Pocosin, Jay F. Bolin

Biological Sciences Theses & Dissertations

Pocosins are depressional wetlands maintained by fire. Plants in fire adapted systems can use a variety of mechanisms for survival and recruitment. I examined the seed bank response to fire (500 to 700 °C) and wet heat treatments (50 and 75 °C) in a Virginia small depression pocosin. I quantified seedling abundance, richness, and Sphagnum density. Extant vegetation was sampled with a nested plot design at each seed bank sampling area. The seed flora was compared with the extant vegetation at three size classes with Sorenson similarity values. Data from the fire treatment indicates that a simulated drought burn may …

Relating Water And Otolith Chemistry In Chesapeake Bay, And Their Potential To Identify Essential Seagrass Habitats For Juveniles Of An Estuarine-Dependent Fish, Spotted Seatrout (Cynoscion Nebulosus), Emmanis Dorval

Biological Sciences Theses & Dissertations

A quantitative understanding of habitat use of estuarine-dependent fishes is critical to the conservation of their most essential habitats. Because recruitment and fitness may be influenced by the quality of juvenile habitats, developing methods to quantify habitat-specific survivorship is pivotal to such understanding. An initial step to quantify survivorship is to validate the habitat-specific natural tags contained in otoliths. To this aim I investigated the variability in the chemistry of surface waters and otoliths of juvenile spotted seatrout, Cynoscion nebulosus, in five seagrass habitats of Chesapeake Bay, namely: Potomac, Rappahannock, York, Island, and Eastern Shore. I measured Mg, Ca, …

Comparative Life Histories Of Georgia And Virginia Cotton Rats, Bradley J. Bergstrom, Robert K. Rose

Biological Sciences Faculty Publications

Adult hispid cotton rats (Sigmodon hispidus) were collected from the field monthly for >2 years from populations near the northern edge of their range in Virginia and contemporaneously from south-central Georgia. Body measurements and weights were taken at capture, and after dissection embryos, corpora lutea, and placental scars were counted and measured; testes and seminal vesicles were dissected out, measured, and weighed. This allowed comparison of several life-history parameters between the populations and tests of several life-history hypotheses. The breeding season was up to 2 months longer in Georgia than in Virginia, where there was typically a 3-month …

Graminicolous Fungi Of Virginia: Fungi In Collections 1995-2003, Curtis W. Roane

Virginia Journal of Science

Fungus-grass associations recognized in Virginia from 1995 to 2003 are recorded. Many associations are new to the United States (59), eastern United States (2), and Virginia (21); others extend the known distribution for those previously discovered. These reports contribute to the natural history of Virginia.

Prescribed Fire Impacts To Amphibians And Reptiles In Shelterwood-Harvested Oak-Dominated Forests, Patrick D. Keyser, David J. Sausville, W. Mark Ford, Donald J. Schwab, Patrick H. Brose

Virginia Journal of Science

As part of a larger study examining the role of prescribed fire in regenerating upland oaks (Quercus spp.), seasonal prescribed burns (winter, spring, summer, and unburned control) were applied to first-stage shelterwood-harvested stands on Horsepen Wildlife Management Area in the Virginia Piedmont in 1995. Because fire impacts are poorly documented for herpetofaunal communities, we surveyed these stands in 1996 capturing 133 individuals of ten species during over 12,720 pitfall trapnights. We found no significant differences in relative abundance of Eastern Red-backed Salamanders (Plethodon cinereus) (P = 0.26), American Toads (Bufo americanus) (P = 0.93), …

Response Of Small Mammal Populations To Fescue Hayfield Conversion To Native Warm Season Grasses In Bath County, Virginia, Michael T. Mengak

Virginia Journal of Science

I investigated the effect on small mammal populations of converting an existing fescue (Festuca arundinacea) hayfield to switchgrass (Panicium virgatum) on the George Washington National Forest at Hidden Valley in Bath County, Virginia. Native warm season grasses are thought to provide better habitat than fescue pastures for Northern Bobwhite (Colinus virginianus) and several species of grassland birds as well as herbivorous small mammals. I established one live-trapping grid and conducted trapping (pre-treatment) in both the switchgrass (treatment) and the fescue (control) field in March and May 1997. The treatment field was sprayed with glyphosate …

On The Ecological Status Of The Concept "Boundary Conditions" - A Few Methodological Remarks, Lubomira Burchardt, Krzystof Lastowski, Harold G. Marshall

Biological Sciences Faculty Publications

Plant and animal populations are frequently found in habitats where the environmental conditions are considered extreme or challenging for life form to exist. These conditions may be classified as either: (1) Supreme: a situation characteristic of degradation conditions where only a few species live under stress, and (2) Extra-ordinary: habitats that provide high biodiversity that are under stress conditions. Due to the differences in what we consider extreme conditions, it is necessary to distinguish between these two categories, because they are not comparable. Our presentation will include examples of these two extreme environmental categories.

A Modelling Study Of The Influence Of Environment And Food Supply On Survival Of Crassostrea Gigas Larvae, Eileen E. Hofmann, Eric N. Powell, Eleanor A. Bochenek, John M. Klinck

CCPO Publications

A biochemically based model was developed to simulate the growth, development, and metamorphosis of larvae of the Pacific oyster (Crassostrea gigas). The unique characteristics of the model are that it: (1) defines larvae in terms of their protein, neutral lipid, polar lipid, carbohydrate, and ash content; (2) tracks weight separately from length to follow larval condition; and (3) includes genetic variation in growth efficiency and egg quality to better simulate cohort population dynamics. The model includes parameterizations for filtration, ingestion, and respiration, which determine larval growth rate, and processes controlling larval mortality and metamorphosis. Changes in larval tissue …

Lagrangian Modelling Studies Of Antarctic Krill (Euphausia Superba) Swarm Formation, Eileen E. Hofmann, A. G. Edward Haskell, John M. Klinck, Cathy M. Lascara

CCPO Publications

A two-dimensional Lagrangian particle model was developed to examine the spatial distribution of Antarctic krill (Euphausia superba). The time-dependent location of particles, which represent krill individuals, is determined by random diffusion, foraging activity, and movement induced by the presence of neighbours. Foraging activity is based on prescribed food conditions and is such that krill swim slower and turn more frequently in areas of high food concentration. The presence or absence of neighbours either disperses krill, if the local concentrations become too dense, or coalesces krill, if concentrations become too dilute, respectively. Predation on krill is included and affects …

Effects Of 8 Weeks Of Flexibility And Resistance Training In Older Adults With Type 2 Diabetes, Matthew T. Herriot, Sheri R. Colberg, Henri K. Parson, Tanja Nunnold, Aaron I. Vinik

Human Movement Studies & Special Education Faculty Publications

(First paragraph) Flexibility is often downplayed as unimportant to fitness. However, flexibility training is imperative to maintain full range of motion (ROM) of joints, particularly in individuals with type 2 diabetes, who may experience limited joint mobility due to glycation of joint structures (1). Maladies such as “frozen shoulder” are common complaints in type 2 diabetes (2).

Stimulation Of Capacitative Calcium Entry In Hl-60 Cells By Nanosecond Pulsed Electric Fields, Jody A. White, Peter F. Blackmore, Karl H. Schoenbach, Stephen J. Beebe

Bioelectrics Publications

Nanosecond pulsed electric fields (nsPEFs) are hypothesized to affect intracellular structures in living cells providing a new means to modulate cell signal transduction mechanisms. The effects of nsPEFs on the release of internal calcium and activation of calcium influx in HL-60 cells were investigated by using real time fluorescent microscopy with Fluo-3 and fluorometry with Fura-2. nsPEFs induced an increase in intracellular calcium levels that was seen in all cells. With pulses of 60 ns duration and electric fields between 4 and 15 kV/cm, intracellular calcium increased 200-700 nM, respectively, above basal levels (similar to100 nM), while the uptake of …

Computational Protein Biomarker Prediction: A Case Study For Prostate Cancer, Michael Wagner, Dayanand N. Naik, Alex Pothen, Srinivas Kasukurti, Raghu Ram Devineni, Bao-Ling Adam, O. John Semmes, George L. Wright Jr.

Mathematics & Statistics Faculty Publications

Background: Recent technological advances in mass spectrometry pose challenges in computational mathematics and statistics to process the mass spectral data into predictive models with clinical and biological significance. We discuss several classification-based approaches to finding protein biomarker candidates using protein profiles obtained via mass spectrometry, and we assess their statistical significance. Our overall goal is to implicate peaks that have a high likelihood of being biologically linked to a given disease state, and thus to narrow the search for biomarker candidates.

Results: Thorough cross-validation studies and randomization tests are performed on a prostate cancer dataset with over 300 patients, obtained …

Characterization Of Association Patterns Of Coastal Migratory Bottlenose Dolphins, Tursiops Truncatus, In The Nearshore Waters Of Virginia Beach, Virginia, Holly Fearnbach

Biological Sciences Theses & Dissertations

Bottlenose dolphins, Tursiops truncatus, commonly occur in fission-fusion social systems. For this study, I analyzed photo-identification data from 1994 to 1999 to describe association patterns of bottlenose dolphins in the nearshore waters of Virginia Beach, Virginia. Bottlenose dolphins are present seasonally (late April until early November) in these waters and individuals are considered to be members of the North Atlantic coastal migratory stock. I selected 78 individuals for detailed analyses from the 972 dolphins identified in the study area. Those chosen as “select” dolphins had been sighted at least five times in three of the six study years; all …

Dissecting The Loci Of Low-Level Quinine Resistance In Malaria Parasites, Michael T. Ferdig, Roland A. Cooper, Jianbing Mu, Bingbing Deng, Deirdre A. Joy, Xin-Zhuan Su, Thomas E. Wellems

Biological Sciences Faculty Publications

Quinine (QN) remains effective against Plasmodium falciparum, but its decreasing efficacy is documented from different continents. Multiple genes are likely to contribute to the evolution of QN resistance. To locate genes contributing to QN response variation, we have searched a P. falciparum genetic cross for quantitative trait loci (QTL). Results identify additive QTL in segments of chromosomes (Chrs) 13, 7 and 5, and pairwise effects from two additional loci of Chrs 9 and 6 that interact, respectively, with the QTL of Chrs 13 and 7. The mapped segments of Chrs 7 and 5 contain pfcrt, the determinant of …

Virulence Factors Of The Group A Streptococci And Genes That Regulate Their Expression, Wayne Hines

Biological Sciences Faculty Publications

Group A streptococci produce a wide variety of extracellular (cell-associated and released) virulence factors. The function of these factors varies and includes roles in adhesion, spreading, tissue destruction, immune system evasion, and cell toxicity. How these factors are regulated with regard to one another is important for this organism's ability to bring about the variety of diseases this microbe is capable of causing. Therefore, along with the multitude of virulence factors, there are a number of regulatory systems that regulate, either directly or indirectly, the production of these factors and therefore influence the pathogenesis of group A streptococcal infections.

How Many Slides? Documented Cytotechnologist Workload, Sophie K, Thompson, Eileen Mason

School of Medical Diagnostics & Translational Sciences Publications

(First paragraph) This paper relays workload information obtained as part of an ergonomics survey.1 Data were obtained on the number of slides evaluated daily, workplace setting, hours worked, and demographic information.

Advection, Krill, And Antarctic Marine Ecosystems, Eileen E. Hofmann, Eugene J. Murphy

CCPO Publications

Advective processes are recognized as being important in structuring and maintaining marine ecosystems. In the Southern Ocean advective effects are perhaps most clearly observed because the Antarctic Circumpolar Current (ACC) provides a connection between most parts of the system, including open ocean and continental shelf regions. The ACC also provides a mechanism for large-scale transport of plankton, such as Antarctic krill (Euphousia superba Dana), which is an important component of the Southern Ocean food web. This overview provides a summary of recent observational and modelling results that consider the importance of advection to the Southern Ocean ecosystem and, in particular, …

Analytical Intercomparison Between Flow Injection-Chemiluminescence And Flow Injection-Spectrophotometry For The Determination Of Picomolar Concentrations Of Iron In Seawater, Andrew R. Bowie, Peter N. Sedwick, Paul J. Worsfold

OES Faculty Publications

A lab- and ship-based analytical intercomparison of two flow injection methods for the determination of iron in seawater was conducted, using three different sets of seawater samples collected from the Southern Ocean and South Atlantic. In one exercise, iron was determined in three different size-fractions (< 0.03 &μm, < 0.4 μm, and unfiltered) in an effort to better characterize the operational nature of each analytical technique with respect to filter size. Measured Fe concentrations were in the range 0.19 to 1.19 nM using flow injection with luminol chemiluminescence detection (FI-CL), and 0.07 to 1.54 nM using flow injection with catalytic spectrophotometric detection with N, N-dimethyl-p-phenylenediamine dihydrochloride (FI-DPD). The arithmetic mean for the FI-CL method was higher (by 0.09 nM) than the FI-DPD method for dissolved (< 0.4 μm) Fe, a difference that is comparable to the analytical blanks, which were as high as 0.13 nM ( CL) and 0.09 nM (DPD). There was generally good agreement between the FI-CL determinations for the < 0.03 μm size fraction and the FI-DPD determinations for the < 0.4 μm size fraction in freshly collected samples. Differences in total-dissolvable ( unfiltered) Fe concentrations determined by the two FI methods were more variable, reflecting the added complexity associated with the analysis of partially digested particulate material in these samples. Overall, however, the FI-CL determinations were significantly (P = 0.05) lower than the FI-DPD determinations for the unfiltered samples. Our results suggest that the observed, systematic inter-method differences reflect measurement of different physicochemical fractions of Fe present in seawater, such that colloidal and/or organic iron species are better determined by the FI-CL method than the FI-DPD method. This idea is supported by our observation that inter-method differences were largest for freshly collected acidified seawater, which suggests extended storage (>6 months) of acidified samples as a possible protocol for the determination of dissolved iron in seawater.

Physical Forcing Of Phytoplankton Community Structure And Primary Production In Continental Shelf Waters Of The Western Antarctic Peninsula, Barbara B. Prézelin, Eileen E. Hofmann, Mark Moline, John M. Klinck

OES Faculty Publications

Analyses of a multidisciplinary data set, collected in continental shelf waters of the Western Antarctic Peninsula (WAP) during austral summer of January 1993, identified a previously unrecognized forcing mechanism that sets up a physical and chemical structure that supports and assures site-specific diatom-dominated communities and enhanced biological production (Prézelin et al., 2000). This forcing is active when the southern boundary of the Antarctic Circumpolar Current (ACC) flows along the shelf edge, thereby facilitating onshelf bottom intrusions of nutrient-rich Upper Circumpolar Deep Water (UCDW), which then is upwelled or mixed into the upper water column. At times or locations where UCDW …