Digital Commons Network^™

Seasonal Variation In Diet Of A Marginal Population Of The Hispid Cotton Rat, Sigmodon Hispidus, Lynn A. Walker, Robert K. Rose

Virginia Journal of Science

Cotton rats live in oldfields, habitats with a variety of mostly herbaceous plants. Based on other studies, the hispid cotton rat, Sigmodon hispidus, eats many kinds of herbaceous plants but grasses predominate. In contrast, our population of cotton rats ate many monocots but mostly they were not grasses. Our study sought to determine the diet of the cotton rat in eastern Virginia, near the northern limit of distribution on the Atlantic Coast. Fecal samples, collected each month during an on-going capture-mark-release demographic study of the rodent community, were analyzed using a standard method. A greater variety of foods (including …

Simon Leung Squatting, Waiting, Kim Paice

Reconstruction: Studies in Contemporary Culture

[Introduction]

Born in Hong Kong and raised there and in Northern California, Simon Leung is an accomplished intellectual—activist, artist, curator, writer, and editor [1]. The mainstay of his art since 1994 has been a series of squatting projects in which the chief concerns are with migration, performativity, and law. Each project was a temporary intervention in a particular city that figured in the interlinked movements of people, capital, and language. To date, there have been four squatting projects; the first was located in Berlin. Leung also created a fifth one for the Third Triennial Exhibition in Guangzhou, China …

Feminisms In Stanley Kubrick's Eyes Wide Shut, Emily G. Brown

Institute for the Humanities Theses

With Eyes Wide Shut, Stanley Kubrick examines the causes and conditions in which men are more powerful and men's production, ideas and activities are seen as having greater value and higher status than women's. Eyes Wide Shut's (EWS) renders the tension between Bill (Tom Cruise) and Alice Hartford (Nicole Kidman) in the modem struggle to find balance between the institution of marriage and their autonomous selves visible. As Bill's travels dominate the film, little beyond the first scene of Alice's disrobed body and the last scene highlighting her psychological stability are shown. We follow Bill as he meets several women; …

A Strategic Planning Decision Support Methodology In Emergency Department Preparedness For Mass Casualty Events, Adrian Spencer Benson

Computational Modeling & Simulation Engineering Theses & Dissertations

This study's objective is to design a strategic planning decision support methodology to improve Emergency Department (ED) preparedness for Mass Casualty Events (MCEs). This effort will enable hospital and medical strategic planners to evaluate alternatives which improve ED capacity. This comparative analysis illuminates the relative performance of alternatives involving three improvement scenarios for an ED, involving various increases in trauma bay, examination room, radiology, surgery, and recovery/observation study capacities. To illustrate this decision methodology, a Discrete Event Simulation (DES) was implemented in Arena, and used a mixture of Subject Matter Expert (SME) estimates and appropriate notional data. The design of …

Optics And Remote Sensing Of Bahamian Carbonate Sediment Whitings And Potential Relationship To Wind-Driven Langmuir Circulation, H. M. Dierssen, Richard C. Zimmerman, David J. Burdige

OES Faculty Publications

Regions of milky white seas or "whitings" periodically occur to the west of Andros Island along the Great Bahama Bank where the bottom sediment consists of fine-grained aragonite mud. We present measurements of inherent optical properties within a sediment whiting patch and discuss the potential for monitoring the frequency, extent, and quantity of suspended matter from ocean colour satellite imagery. Sea spectral reflectance measured in situ and remotely from space revealed highly reflective waters elevated across the visible spectrum (i.e., "whitened") with a peak at 490 nm. Particulate backscattering was an order of magnitude higher than that measured at other …

C2 Domain Ontology Within Our Lifetime, Leslie Winters, Andreas Tolk

Computational Modeling & Simulation Engineering Faculty Publications

Agile Command and Control (C2) requires agile information sharing with an increasingly wide variety of military and non-military partners. While current net-centric approaches may improve information sharing within a particular niche of C2, they do not support information sharing across the larger C2 domain. Although not a silver bullet, the development and application of a C2 domain ontology to improve C2 data and service integration appears to be increasingly realistic. In fact, there are several examples of successful ontology applications in domains such as medicine, biology, and engineering, and the new discipline of Applied Ontology is emerging. C2 data, architecture, …

Applying The Information Age Combat Model: Quantitative Analysis Of Network Centric Operations, Sean Deller, Shannon R. Bowling, Ghaith A. Rabadi, Andreas Tolk, Michael I. Bell

Computational Modeling & Simulation Engineering Faculty Publications

The nature of and the approach to command and control is evolving in order to meet the challenges of Information Age warfare. One of the main tasks of command and control is the arrangement of the assets within a combat force in order to ensure their ability to manage and exploit information. Connectivity between the various assets represents existence, capacity, reliability, and other attributes of links establishing the connectivity. The Information Age Combat Model was introduced by Cares in 2005 to contribute to the development of an understanding of the influence of connectivity on force effectiveness that can lead eventually …

The Cultural Production Of Health Inequalities: A Cross-Sectional, Multilevel Examination Of 52 Countries, Carol L. Mansyur, Benjamin C. Amick Iii, Ronald B. Harrist, Luisa Franzini, Robert E. Roberts

Community & Environmental Health Faculty Publications

In a 2001 report, the U.S. National Institutes of Health called for more integration of the social sciences into health-related research, including research guided by theories and methods that take social and cultural systems into consideration. Based on a theoretical framework that integrates Hofstede's cultural dimensions with sociological theory, the authors used multilevel modeling to explore the association of culture with structural inequality and health disparities. Their results support the idea that cultural dimensions and social structure, along with economic development, may account for much of the cross-national variation in the distribution of health inequalities. Sensitivity tests also suggest that …

Socioeconomic Disparity In Healthcare-Seeking Behavior Among Chinese Women With Genitourinary Symptoms, Qi Zhang, Diane Lauderdale, Shanshan Mou, William I. Parish, Edward O. Laumann, John Schneider

Community & Environmental Health Faculty Publications

Background: Sexually transmitted infections (STIs) are of growing concern in China. Understanding the relationship between socioeconomic status (SES) and healthcare-seeking (HCS) behavior will help design effective policies to contain the epidemic of STIs across SES.

Methods: We used the Chinese Health and Family Life Survey, a nationally representative survey of 3813 adults from 48 Chinese cities and counties during 1999-2000. We studied the 730 women with at least one genito-urinary (GU) symptom. HCS was measured by whether respondents visited a hospital or an unrecognized clinic, self-treatment, or doing nothing. Formal treatment was defined as visiting a hospital. SES was measured …

A New Pulsed Electric Field Therapy For Melanoma Disrupts The Tumor's Blood Supply And Causes Complete Remission Without Recurrence, Richard Nuccitelli, Xinhua Chen, Andrei G. Pakhomov, Wallace H. Baldwin, Saleh Sheikh, Jennifer L. Pomicter, Wei Ren, Chris Osgood, R. James Swanson, Juergen F. Kolb, Stephen J. Beebe, Karl H. Schoenbach

Bioelectrics Publications

We have discovered a new, ultrafast therapy for treating skin cancer that is extremely effective with a total electric field exposure time of only 180 mu sec. The application of 300 high-voltage (40 kV/cm), ultrashort (300 nsec) electrical pulses to murine melanomas in vivo triggers both necrosis and apoptosis, resulting in complete tumor remission within an average of 47 days in the 17 animals treated. None of these melanomas recurred during a 4-month period after the initial melanoma had disappeared. These pulses generate small, long-lasting, rectifying nanopores in the plasma membrane of exposed cells, resulting in increased membrane permeability to …

Electroporation For The Delivery Of Dna-Based Vaccines And Immunotherapeutics: Current Clinical Developments, Angela M. Bodles-Brakhop, Richard Heller, Ruxandra Draghia-Akli

Bioelectrics Publications

Electroporation (EP) has been used in basic research for the past 25 years to aid in the transfer of DNA into cells in vitro. EP in vivo enhances transfer of DNA vaccines and therapeutic plasmids to the skin, muscle, tumors, and other tissues resulting in high levels of expression, often with serological and clinical benefits. the recent interest in nonviral gene transfer as treatment options for a vast array of conditions has resulted in the refinement and optimization of EP technology. current research has revealed that EP can be successfully used in many species, including humans. clinical trials are …

Potential Export Of Unattached Benthic Macroalgae To The Deep Sea Through Wind Driven Langmuir Circulation, H. M. Dierssen, Richard C. Zimmerman, Lisa A. Drake, David J. Burdige

OES Faculty Publications

Carbon export to the deep sea is conventionally attributed to the sinking of open ocean phytoplankton. Here, we report a Langmuir supercell event driven by high winds across the shallow Great Bahama Bank that organized benthic non-attached macroalgae, Colpomenia sp., into visible windrows on the seafloor. Ocean color satellite imagery obtained before and after the windrows revealed a 588 km² patch that rapidly shifted from highly productive macroalgae to bare sand. We assess a number of possible fates for this macroalgae and contend that this event potentially transported negatively buoyant macroalgae to the deep Tongue of the Ocean …

Influence Of Irradiance And Iron On The Growth Of Colonial Phaeocystic Antarctica: Implications For Seasonal Bloom Dynamics In The Ross Sea, Antarctica, Nathan S. Garcia, Peter N. Sedwick, Giacomo R. Ditullio

OES Faculty Publications

Laboratory culture experiments were used to investigate the growth rate of colonial Phaeocystis anarctica as a function of irradiance and dissolved iron concentration. The experiments were conducted with a P. antarctica strain isolated from the southern Ross Sea, Antarctica, and made use of natural, low-iron (P. antarctica attained an average maximum cell-specific growth rate of 0.37 d^-1at an irradiance of 68 μE m^-2s^-1, above which growth rates decreased to 0.27 d^-1 at an irradiance of 314 μE m^-2s^-1. The dependence of growth rate on ambient dissolved iron concentration was …

Cirene Air-Sea Interactions In The Seychelles-Chagos Thermocline Ridge Region, J. Vialard, J. P. Duvel, M. J. Mcphaden, P. Bouruet-Aubertot, B. Ward, E. Key, D. Bourras, R. Weller, P. Minnett, A. Weil

OES Faculty Publications

A field experiment in the southwestern Indian Ocean provides new insights into ocean-atmosphere interactions in a key climatic region.

Thin Layer Formation During Runaway Stratification In The Tidally Dynamic San Francisco Estuary, Alexander B. Bochdansky, Stephen M. Bollens

OES Faculty Publications

During the course of a year, we repeatedly collected high-resolution vertical fluorometer data timed to coincide with a specific state during the tidal cycle. The time (end of the ebb during neap tide) and the location (a deep channel half-way between the Golden Gate and the point of tidally averaged bottom salinity of 2 psu) were chosen with the goal to observe runaway stratification. We consistently found at least one pronounced chlorophyll peak in the water column; however, the vertical location of these peaks varied within three types including surface, bottom and subsurface maxima. Our results showed that heterogeneity of …

Peptide Hydrolysis And The Uptake Of Dipeptides By Phytoplankton, Margaret R. Mulholland, Cindy Lee

OES Faculty Publications

Rates of peptide hydrolysis (using the fluorescent substrate, lucifer yellow anhydride-labeled tetra-alanine) and dipeptide uptake (using dually labeled, ¹⁵N and ¹³C, dialanine) were measured in phytoplankton cultures and in natural populations during algal blooms dominated by one or two taxa. During most sampling events, both peptide hydrolysis and dipeptide uptake were greatest in the size fraction containing the dominant phytoplankter, suggesting that phytoplankton contribute substantially to or may even dominate observed extracellular peptide hydrolysis and dipeptide uptake in the environment. These are the first data suggesting that dipeptides may be taken up directly by phytoplankton and this may …

Spatial Variation In Otolith Chemistry Of Atlantic Croaker Larvae In The Mid-Atlantic Bight, Jason J. Schaffler, Christian S. Reiss, Cynthia M. Jones

OES Faculty Publications

Larval Atlantic croaker Micropogonias undulatus (1 to 7 mm in standard length) were collected on the east coast of the United States from North Carolina to Delaware during 2000. We defined 3 water-mass boundaries for potential groups of spawning Atlantic croaker using temperature and salinity measured at each sampling station. We tested the hypothesis that distinct otolith chemistries existed among 3 groups of larval Atlantic croaker collected from these water masses using solution-based inductively coupled plasma-mass spectrometry. Multivariate analysis of variance indicated that otolith chemistry differed significantly among water masses. Using a quadratic discriminant function, we were able to correctly …

Patterns Of Larval Atlantic Croaker Ingress Into Chesapeake Bay, Usa, Jason J. Schaffler, Christian S. Reiss, Cynthia M. Jones

OES Faculty Publications

We compared ingress patterns of Atlantic croaker Micropogonias undulatus larvae into Chesapeake Bay, USA, with published ingress patterns through barrier island inlets, the accepted model for larval fish ingress. This model asserts that larvae ingress on night flood tides at the flooddominated side of the inlet and at all depths. At the Chesapeake Bay mouth and in the adjacent coastal waters, we compared the distribution of abundance, size, age, and growth rates of croaker prior to ingress, In contrast to the barrier island inlet model, croaker larvae were more abundant at depth than closer to the surface regardless of location. …

Synergistic Effects Of Iron And Temperature On Antarctic Phytoplankton And Microzooplankton Assemblages, J. M. Rose, Y. Feng, G. R. Ditullio, R. B. Dunbar, C. E. Hare, P. A. Lee, M. Lohan, M. Long, W. O. Smith Jr., B. Sohst, S. Tozzi, Y. Zhang, D. A. Hutchins

OES Faculty Publications

Iron availability and temperature are important limiting factors for the biota in many areas of the world ocean, and both have been predicted to change in future climate scenarios. However, the impacts of combined changes in these two key factors on microbial trophic dynamics and nutrient cycling are unknown. We examined the relative effects of iron addition (+1 nM) and increased temperature (+4° C) on plankton assemblages of the Ross Sea, Antarctica, a region characterized by annual algal blooms and an active microbial community. Increased iron and temperature individually had consistently significant but relatively minor positive effects on total phytoplankton …

Cross-Basin Comparison Of Phosphorus Stress And Nitrogen Fixation In Trichodesmium, Annette M. Hynes, P. Dreux Chappell, Sonya T. Dyhrman, Scott C. Doney, Eric A. Webb

OES Faculty Publications

We investigated the phosphorus (P) status and N₂ fixation rates of Trichodesmium populations from the North Pacific, western South Pacific, and western North Atlantic. Colonies of Trichodesmium were collected and analyzed for endogenous alkaline phosphatase (AP) activity using enzyme-labeled fluorescence ( ELF) and for nitrogenase activity using acetylene reduction. AP hydrolyzes dissolved inorganic phosphate (DIP) from dissolved organic phosphorus and is active in Trichodesmium colonies experiencing P stress. Across multiple stations in the subtropical North and South Pacific, there was low to moderate ELF labeling in Trichodesmium, although labeling was present in other taxa. In contrast, Trichodesmium ELF …

Geobiology: Evidence For Early Life On Earth And The Search For Life On Other Planets, Sherry L. Cady, Nora Noffke

OES Faculty Publications

Extensive research efforts in the subdisciplinary field of geobiology have focused on the interactions between Earth and life through time. As a consequence, gaps in our knowledge of Earth’s history are closing, and the search for life beyond Earth is expanding. A few examples of geobiology studies designed to advance our understanding of life on early Earth and to improve the chances of finding life on other planets are provided to highlight recent developments and research areas that are on the verge of new discoveries.

Is Seagrass An Important Nursery Habitat For The Caribbean Spiny Lobster, Panulirus Argus, In Florida?, Donald C. Behringer, Mark J. Butler Iv, William Herrnkind, John H. Hunt, Charles A. Acosta, William C. Sharp

Biological Sciences Faculty Publications

Caribbean spiny lobster (Panulirus argus) settle preferentially in macroalgal-covered hard-bottom habitat, but seagrass is more prevalent in Florida (United States) and the Caribbean, so even low settlement of lobsters within seagrass could contribute substantially to recruitment if post-settlement survival and growth were high. We tested the role of seagrass and hard-bottom habitats for P. argus recruitment in three ways. We first explored possible density-dependent regulation of early benthic juvenile lobster survival within cages deployed in seagrass and hard-bottom habitats. Second, we compared settlement and survival of P. argus in both habitats, by comparing the recovery of microwire-tagged early …

Regulation Of Intracellular Calcium Concentration By Nanosecond Pulsed Electric Fields, Shaka S. Scarlett, Jody A. White, Peter F. Blackmore, Karl H. Schoenbach, Juergen Kolb

Bioelectrics Publications

Changes in [Ca²⁺]_i response of individual Jurkat cells to nanosecond pulsed electric fields (nsPEFs) of 60 ns and field strengths of 25, 50, and 100 kV/cm were investigated. The magnitude of the nsPEF-induced rise in [Ca²⁺]_i was dependent on the electric field strength. With 25 and 50 kV/cm, the [Ca²⁺]_i response was due to the release of Ca²⁺ from intracellular stores and occurred in less than 18 ms. With 100 kV/cm, the increase in [Ca²⁺]_i was due to both internal release and to influx across the plasma …

Determinants Of Increased Safety Belt Use By High School Students In Motor Vehicles: The Influence Of Parents And Peers And Implications For Virginia's Graduated Driver Licensing Laws, Georjeane Linley Blumling

School of Public Service Theses & Dissertations

Motor vehicle crashes are the number one cause of injuries and fatalities for persons 15-19 years of age in the United States. The higher fatality rate is caused in part from the lack of driving experience and the increased risk taking behaviors of adolescent drivers. Graduated driver licensing laws have been enacted in most states to address the risks associated with inexperience by adding restrictions on nighttime driving and limiting the number of teen passengers in the vehicle for novice drivers.

Inconsistent use or non-use of a safety belt when riding in a motor vehicle is a prevalent risk taking …

Computational Studies On R67 Dihydrofolate Reductase: An Investigation Into Its Unique Binding Patterns, Chuanyin Shi

Theses and Dissertations in Biomedical Sciences

R67 dihydrofolate reductase (R67 DHFR) is a plasmid encoded enzyme which catalyzes the reduction of dihydrofolate (DHF) to tetrahydrofolate (THF) using NADPH as a cofactor. R67 DHFR is a homo-tetramer and D2 symmetric. It contains only one active site, which spans the central channel of the enzyme. The active site can bind either two reactants (DHF), two cofactors (NADPH) or one of each (NADPH/DHF), which is the productive ternary complex (i.e. the complex which yields product). In order to favor formation of the productive complex, this enzyme exhibits binding cooperativity. Unlike other allosteric enzymes which achieve binding cooperativity through conformational …

Wisc-Iv And Iva+Plus Pattern Analysis: Assessment Of Attention-Deficit /Hyperactivity Disorder, Kevin K. Tsang

Psychology Theses & Dissertations

Diagnosis of attention-deficit/hyperactivity disorder (ADHD) is a challenging practice with no definitive diagnostic test. This study sought to evaluate the use of a pattern of performance method of inference in ADHD assessment that examines an individual's general intellectual ability in comparison to his or her own attention skills. WISC-IV scores, IVA+Plus quotients, and basic demographic information were collected from patient files of children previously evaluated by the Eastern Virginia Medical School Neuropsychology Clinic. Children with and without ADHD were compared by analyzing the following difference or delta score discrepancies: (a) WISC-IV General Ability Index (GAI) minus WISC-IV Working Memory Index, …

Transformation Paradox: A Framework For The Analysis Of Politics In Enterprise Transformations, Cindy S. Miller

Engineering Management & Systems Engineering Theses & Dissertations

The purpose of this research is to develop a theoretical framework for the analysis of politics in enterprise transformations using a dialectical analysis approach (Hegel, 1989; Heraclitus, 1979; Pinkard, 1988; Skinner, 1978a, 1978b) and conduct an evaluation of the framework validity. The framework is constructed using a dialectical analysis of concepts stemming from the work of Alford and Friedland (1992) and considers four theoretical perspectives: autocratic, bureaucratic, pluralistic, and cognitive. The framework is then validated by means of qualitative metrics and adherence to critical ideology.

This research addresses the problem that there is no holistic theoretical framework for the analysis …

Export Of Terrestrial Dissolved Organic Matter Along A River To Ocean Transect Of The Lower Chesapeake Bay Investigated By Advanced Analytical Techniques, Rachel Leigh Sleighter

Chemistry & Biochemistry Theses & Dissertations

Ultrahigh resolution electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS) has proved essential for the complete separation of the thousands of peaks present in natural organic matter (NOM), a complex assemblage of organic molecules present in water, soils, and sediments. An improved understanding of its composition is crucial to understand how pollutants interact with NOM and how NOM cycles through global carbon cycles.

Optimizing the acquisition and handling of the FTICR mass spectra is the first step to obtaining high quality data. A simple method to internally calibrate the peaks in the complex spectra, using naturally present fatty …

Biogenic Tracers Through The Holocene On The Alaskan Shelf, Carie A. Curry

OES Theses and Dissertations

Dramatic environmental changes in the Arctic Ocean have been observed for the last two decades including changing the amount of sea ice thickness and extent, and increased river discharge. In order to put these and other current day observations into historical context and perhaps reveal mechanisms controlling them, a suite of paleo-proxies were used to analyze two high resolution cores collected on the 2005 HOTRAX expedition. The goals of this research were: (1) develop an analytical method for determining biogenic calcite, (2) identify the major sources of biogenic matter into the system over the Holocene, and (3) assemble the history …

Molecular Dynamics Study Of Single Stranded Peptide Nucleic Acids, Anna K. Manukyan

Theses and Dissertations in Biomedical Sciences

A PNA molecule is a DNA strand where the sugar-phosphate backbone has been replaced by a structurally homomorphous pseudopeptide chain consisting of N(2-aminoethyl)-glycine units. PNA binds strongly to both DNA and RNA. However, an analysis of the X-ray and NMR data show that the dihedral angles of PNA/DNA or PNA/DNA complexes are very different from those of DNA:DNA or RNA:RNA complexes. In addition, the PNA strand is very flexible. One way to improve the binding affinity of PNA for DNA/RNA is to design a more pre-organized PNA structure. An effective way to rigidify the PNA strand is to introduce …