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Section Abstracts: Medical Sciences

Virginia Journal of Science

Abstracts of the Medical Sciences Section for the 92nd Annual Meeting of the Virginia Academy of Science, May 13-15, 2014, Virginia Commonwealth University, Richmond, Virginia

Phytoplankton In Virginia Lakes And Reservoirs: Part Ii, Harold G. Marshall

Virginia Journal of Science

Phytoplankton composition from 16 Virginia lakes and reservoirs are discussed with emphasis on the dominant taxa, algal bloom producers, and potentially harmful species at these locations. This is a companion study to the more comprehensive publication regarding Virginia freshwater phytoplankton by Marshall (2013).

A 'Fundamental Theory' Of Education Grounded In Ontology? A Phenomenological Rejoinder, James M. Magrini

Reconstruction: Studies in Contemporary Culture

This paper explores the phenomenological possibility of transcending the impoverished ontological state of contemporary "standardized" education (social efficiency), which forecloses original ways of Being-and-learning. Focused on the notion of phenomenological self-hood, I elucidate a fundamental educational theory, which holds the potential of inspiring a renewed conception of curriculum design and praxis. Envisioning a reconceived notion of world and human being, I look to the realm of "absorbed coping," a mode of Being-in-the-world that antedates both practical comportment and theoretical comportment. It is a mode of existence wherein we literally "learn" to respond to the "address" of …

Kant's Theory Of Reason: Is It Metaphysics After All? Kant, Rousseau, Yoga, And The Operations Of Reason In Light Of Understanding And Knowing, Guillemette Johnston

Reconstruction: Studies in Contemporary Culture

This paper defines steps in Kant's understanding of perception. A detailed account of Kant's transcendental aesthetics explains why philosophers associate Kant's theory of knowledge with the death of metaphysics. Kant's philosophy, a reaction to Hume's observations on cause/effect relations, determines the very nature of contemporary metaphysics. A review of Kant's interpretation of knowledge in light of reason and perception, however, reveals that for Kant, knowledge acquisition occurs via an introverted vision relating to inner and outer environment. This justifies interpreting his work as metaphysics, and supports comparison of Kant's views to Rousseau's perspectives, which are associated with yogic concepts of …

Who Emerges In Conversation? An Abolitionist Interruption That Teaches, Cathrine Ryther

Reconstruction: Studies in Contemporary Culture

I draw on Maurice Blanchot's distinction between dialogue and conversation in order to argue for reconsidering conversation as a distinct resource for encountering and attending to otherness rather than sameness. Using Blanchot's concepts as a guide, I compare the figures that emerge in a platonic dialogue with those that emerge in a conversation constructed from the work of two contemporary philosophers: Adriana Cavarero and Jacques Rancière. Allowing these philosophers to do most of the talking, I highlight the emergence in conversation of abolitionist figures with symbolic freedom, in contrast to the emergence in dialogue of substantive and symbolically ordered figures.

A Collaborative International Research Program On The Coupled North Atlantic-Arctic System: Science Plan, Eileen E. Hoffmann, Mike St. John, Heather M. Benway

CCPO Publications

This North Atlantic-Arctic science plan is derived from an international workshop held in April 2014 with support from the National Science Foundation Division of Ocean Sciences and the European Union (EU). The workshop was designed to facilitate development of a core vision for advancing the next phase of research on the North Atlantic-Arctic system and strengthening international collaborations within and between the EU and North America.

Current Status And Long-Term Trends In Water Quality And Living Resources In The Virginia Tributaries And Chesapeake Bay Mainstem From 1985 Through 2012, Daniel M. Dauer, Todd A. Egerton, John R. Donat, Michael F. Lane, Suzanne C. Doughten, Cindy Johnson

Status and Trends for Virginia Chesapeake Bay

The period prior to the implementation of the Chesapeake Bay Monitoring Program was characterized by a marked decline in the water quality of the Chesapeake Bay. The disappearance of submerged aquatic vegetation in certain regions of the Bay, declines in the abundance of some commercially and recreationally important species, increases in the incidence of low dissolved oxygen events, changes in the Bay's food web, and other ecological problems have been related to the deteriorating water quality (e.g. USEPA, 1982,1983;Officer et al.,1984; Orth and Moore, 1984). The results of concentrated research efforts in the late 1970s and early 1980s stimulated the …

Helicopter Parents Of Community College Students: How Community College Professionals Operationally Define And Address This Phenomenon, Helen C. Hightower

Educational Leadership & Workforce Development Theses & Dissertations

This study examined whether the phenomenon of parental over-involvement occurred in the Virginia Community College System. Concern has been expressed in the popular and academic literature in recent years over the increased level of parental involvement at four year institutions whose student bodies consist almost exclusively of traditional-aged students. With a mix of traditional-aged and non-traditional students at community colleges, this study investigated whether or not community college employees expressed similar concerns as their counterparts at senior institutions.

The study was designed using a mixed methods approach and utilized a triangulation of results in order to answer four research questions. …

Relationship Between Virginia's Fiscal Effort And Public School Graduation Rates, Bryce Ryan Johnson

Educational Leadership & Workforce Development Theses & Dissertations

Prior education finance studies have measured the effect of funding on various student achievement variables. These studies demonstrate the need for resources in education, but this need requires further exploration. Previous literature shows several limitations regarding study length, scope and fiscal resources analyzed. This study further investigates school funding by analyzing the relationship between school funding and high school graduation rates over a nine-year time frame.

This research examines what role Virginia's school districts' division fiscal effort (the proportion of its wealth invested in K-12 public education) plays in determining several identified measurable student outcomes from 2003 to 2012. The …

The Ethnobotany Of Pistacia Eurycarpa Yalt. In Iraqi-Kurdistan: Its Uses, Chemical Composition, And Anti-Biotic Activity Of Its Resin, Peter W. Schafran

Biological Sciences Theses & Dissertations

Pistacia eurycarpa Yalt. is a wild relative of pistachio (P. vera L.} that grows in the Zagros Mountains. For the Kurds who inhabit these mountains the tree has practical and cultural applications. All parts of this tree have a use, for structural materials, food, and medicine. While weII known in this region, the ethnobotany of P. eurycarpa is unknown in the outside world. I spent May and June of 2011 - 2013 in Sulaimani, Kurdistan, Iraq, collecting information on this tree. In this time period I was able to witness the harvest of unripe fruits. Information about the tree …

A Study Of The Factors That Predict Academic Success And Retention Of Student-Athletes, April A. Brecht

Educational Leadership & Workforce Development Theses & Dissertations

Institutions across the country and the National Collegiate Athletic Association (NCAA) are continuously looking for ways to improve the academic success and retention of students. Most research focuses on the use of cognitive factors as predictors; however, there has been an increase in the use of non-cognitive factors in this research. This study used logistical regression in the examination of non-cognitive, cognitive, and demographic factors as predictors of academic success and retention of Division I first year student-athletes at a large, public, moderately selective, research extensive institution. The population consisted of 275 students who participated in 16 intercollegiate teams. The …

Characterization Of An Impulse Radiating Antenna In The Near Field, Chandra Barjracharya

Electrical & Computer Engineering Theses & Dissertations

The biological effects of intense sub-nanosecond pulses on tissues or cells are in the dielectric domain and not based on thermal loading as in the conventional microwave radiation, which may lead to an entirely new approach of modifying cell functions. Moreover, the resulting cell functional change may be detected with higher resolution by broadband, sub-nanosecond pulses than conventional narrowband systems. The delivery of intense sub-nanosecond pulses to near-field biological tissues, however, has not been studied, not mentioning the focal depth and volume. In this dissertation, for the first time, an impulse radiating antenna with a balanced feed structure is studied …

Ray- And Wave-Theoretic Approach To Electromagnetic Scattering From Radially Inhomogeneous Spheres And Cylinders, Michael A. Pohrivchak

Mathematics & Statistics Theses & Dissertations

With applications in the areas of chemistry, physics, microbiology, meteorology, radar, astronomy, and many other fields, electromagnetic scattering is an important area of research. Many everyday phenomena that we experience are a result of the scattering of electromagnetic and acoustic waves. In this dissertation, the scattering of plane electromagnetic waves from radially inhomogeneous spheres and cylinders using both ray- and wave-theoretic principles is considered. Chapters 2 and 3 examine the use of the ray approach. The deviation undergone by an incident ray from its original direction is related to the angle through which the radius vector turns from the point …

Modeling Stem Cell Population Dynamics, Samiur Arif

Computer Science Theses & Dissertations

Because of the stochastic nature of biological systems, mathematical and computational modeling approaches have become more acceptable to experimentalists and clinicians in recent years as contributing to new understandings of complicated cell mechanisms and tissue physiology. Indeed, even single cell or small tissue samples are complex dynamic systems that adapt to environmental challenges in space and time which is poorly understood. Mathematical models and computer simulations can explain and uncover unknown aspects of cell behavior and tissue functions. Models based on key biological mechanisms can give interesting insights and formulate predictions that cannot be derived from physical experiments or statistical …

Benthic And Planktonic Microalgal Community Structure And Primary Productivity In Lower Chesapeake Bay, Matthew Reginald Semcheski

Biological Sciences Theses & Dissertations

Microalgal populations are trophically important to a variety of micro- and macroheterotrophs in marine and estuarine systems. In Chesapeake Bay, microalgae facilitate the survival and development of ecologically and economically relevant fauna, including shellfish and finfish populations. While regarded as significant components of coastal environments, microphytobenthic communities are historically understudied. In Chesapeake Bay, the importance of phytoplankton to the ecosystem is understood, but the contribution of microphytobenthos remains unclear. This project surveys intertidal microphytobenthic communities, in relation to phytoplankton communities, around lower Chesapeake Bay describing the taxonomic makeup of these populations, coupled with quantification of cell abundance, biomass, and primary …

Analyzing Cholera Dynamics In Homogeneous And Heterogeneous Environments, Drew Posny

Mathematics & Statistics Theses & Dissertations

Cholera continues to be a serious public health concern in developing countries and the global increase in the number of reported outbreaks suggests that activities to control the diseases and surveillance programs to identify or predict the occurrence of the next outbreaks are not adequate. Mathematical models play a critical role in predicting and understanding disease mechanisms, and have long provided basic insights in the possible ways to control infectious diseases. This dissertation is concerned with mathematical modeling and analysis of cholera dynamics. First, we study an autonomous model in a homogeneous environment with added controls that involves both direct …

Markov Chain Monte Carlo Bayesian Predictive Framework For Artificial Neural Network Committee Modeling And Simulation, Michael S. Goodrich

Computational Modeling & Simulation Engineering Theses & Dissertations

A logical inference method of properly weighting the outputs of an Artificial Neural Network Committee for predictive purposes using Markov Chain Monte Carlo simulation and Bayesian probability is proposed and demonstrated on machine learning data for non-linear regression, binary classification, and 1-of-k classification. Both deterministic and stochastic models are constructed to model the properties of the data. Prediction strategies are compared based on formal Bayesian predictive distribution modeling of the network committee output data and a stochastic estimation method based on the subtraction of determinism from the given data to achieve a stochastic residual using cross validation. Performance for Bayesian …

Balancing Parenthood: Men's Prenatal Expectations And The Family System, Ralitsa Stoyneva Maduro

Psychology Theses & Dissertations

Positive coparenting expectations of new parents have been related to positive coparenting experiences for both mothers and fathers during the transition to parenthood. Furthermore, positive coparenting in the family system has been linked to better and more stable relationship satisfaction for couples, which in turn has resulted in lower postpartum depression and divorce rates. Despite evidence of the positive impact of coparenting balance on the couple's mmantic life, few investigators have examined the manner in which predictors of relationship satisfaction for one parent cross over to affect the other. Furthermore, less in known regarding which family-wise factors increase fathers'ulnerability to …

Determination Of The Ecological Condition Of Benthic Communities Affected By Polycyclic Aromatic Hydrocarbons In The Elizabeth River, Chesapeake Bay, Usa, Adam M. Webb

Biological Sciences Theses & Dissertations

The Southern Branch of the Elizabeth River, a tributary of Chesapeake Bay, has historically been polluted with hydrocarbon based industrial by-products. My study compared benthic community condition from two locations in the Southern Branch: the subtidal region near Money Point, historically affected by pollution of polycyclic aromatic hydrocarbons (PAHs), to a subtidal region near Blows Creek on the opposite shore that is putatively designated as unimpacted by P AH contamination. Samples from both study sites in the Southern Branch were compared to the benthic community condition of samples from the same habitat type designations collected as part of the Chesapeake …

Generation Of Bipolar Nanosecond Pulses, Sambasiva Rao Rajulapati

Electrical & Computer Engineering Theses & Dissertations

Bipolar pulse generation has been studied using transmission line technology, which was mainly used for monopolar pulse generation. In this thesis, low impedance, high current, nanosecond pulse generators were designed, constructed and tested. Five transmission lines were connected in parallel, so the impedance was 10 n. The transmission lines were switched by a spark gap switch operated in air. The closing of the switch creates a matched condition on one side of the transmission lines and a short circuit on the other side of the transmission lines. When the transmission lines are precharged, one of the two waves in opposite …

Comparison Of Two Separation Methods For Biological Particles: Field-Flow Fractionation (Fff) And Sucrose Density Gradients, Cody E. Garrison

OES Theses and Dissertations

Sucrose gradient centrifugation and Field-flow fractionation (FFF) are two different particle separation methods that overcome the problems of similar size microorganisms clumping together during standard filtration methods. FFF separates particles based on size and density via the parabolic velocity profile of laminar flow in a ribbon-like channel. The sucrose method separates particles via centrifugation in a density gradient. Both techniques worked well in separating eukaryotic from prokaryotic microbes, with the preferred method depending on the type and relative abundance of organisms to be separated. Minicells were separated from mother cells in transformed Escherichia coli cultures, heterotrophic flagellates (e.g., Diplonema papillatum …

Modeling And Simulation Of Shape Changes Of Red Blood Cells In Shear Flow, John Gounley

Mathematics & Statistics Theses & Dissertations

A description of the biomechanical character of red blood cells is given, along with an introduction to current computational schemes which use deformable capsules to simulate red blood cell shape change. A comprehensive two- and three-dimensional framework for the fluid-structure interaction between a deformable capsule and an ambient flow is provided. This framework is based on the immersed boundary method, using lattice Boltzmann and finite element methods for the fluid and structure, respectively. The characteristic response and recovery times of viscoelastic circular and spherical capsules are compared, and their dependence on simulation parameters is shown. The shape recovery of biconcave …

The Effects Of Changing Winds And Temperatures On The Oceanography Of The Ross Sea In The 21st Century, Walker O. Smith, Michael S. Dinniman, Eileen E. Hofmann, John M. Klinck

CCPO Publications

The Ross Sea is critically important in regulating Antarctic sea ice and is biologically productive, which makes changes in the region's physical environment of global concern. We examined the effects of projected changes in atmospheric temperatures and winds on aspects of the ocean circulation likely important to primary production using a high-resolution sea ice-ocean-ice shelf model of the Ross Sea. The modeled summer sea-ice concentrations decreased by 56% by 2050 and 78% by 2100. The duration of shallow mixed layers over the continental shelf increased by 8.5 and 19.2days in 2050 and 2100, and the mean summer mixed layer depths …

The Toxavapa Toxin-Antitoxin Locus Contributes To The Survival Of Nontypeable Haemophilus Influenzae During Infection, Dabin Ren, Alexis A. Kordis, Daniel E. Sonenshine, Dayle A. Daines

Biological Sciences Faculty Publications

Nontypeable Haemophilus influenzae (NTHi) is an opportunistic pathogen that is a common cause of acute and recurrent mucosal infections. One uncharacterized NTHi toxin-antitoxin (TA) module, NTHI1912-1913, is a host inhibition of growth (higBA) homologue. We hypothesized that this locus, which we designated toxAvapA, contributed to NTHi survival during infection. We deleted toxAvapA and determined that growth of the mutant in defined media was not different from the parent strain. We tested the mutant for persistence during long-term in vitro co-culture with primary human respiratory tissues, which revealed that the DeltatoxAvapA mutant was attenuated for survival. We then …

Bulk Elastic Moduli And Solute Potentials In Leaves Of Freshwater, Coastal, And Marine Hydrophytes. Are Marine Plants More Rigid?, Brant W. Touchette, Sarah E. Marcus, Emily C. Adams

Biological Sciences Faculty Publications

Bulk modulus of elasticity (ɛ), depicting the flexibility of plant tissues, is recognized as an important component in maintaining internal water balance. Elevated ɛ and comparatively low osmotic potential (Ψ_π) may work in concert to effectively maintain vital cellular water content. This concept, termed the ‘cell water conservation hypothesis’, may foster tolerance for lower soil-water potentials in plants while minimizing cell dehydration and shrinkage. Therefore, the accumulation of solutes in marine plants, causing decreases in Ψ_π, play an important role in plant–water relations and likely works with higher ɛ to achieve favourable cell …

Geotraces: Changing The Way We Explore Ocean Chemistry, Robert F. Anderson, Edward Mawji, Gregory A. Cutter, Christopher I. Measures, Catherine Jeandel

OES Faculty Publications

GEOTRACES is an international study of the marine biogeochemical cycles of trace elements and their isotopes (TEIs), designed by marine geochemists to accelerate TEI research under a global program. Combining ocean sections, process studies, data synthesis, and modeling, GEOTRACES will identify and quantify the processes that supply TEIs at ocean boundaries as well as the physical and biological processes that redistribute TEIs within and between ocean basins. Constraining processes that remove TEIs from the ocean will enable complete mass budgets to be generated. Anticipated beneficiaries of GEOTRACES products include scientists studying the sustained health of marine ecosystems and their sensitivity …

Rums: Research For Undergraduates In Math And Science, David Gauthier

Undergraduate Research Symposium

Chair: Dr. David Gauthier, Department of Biological Sciences

Presenters: Elizabeth Smith, Jessica Vincent, Amarilis Dyer, Amy Johnson, Joseph Brown

Poster Session 2, Honors College, Odu

Undergraduate Research Symposium

Featuring Biochemistry, Physics, Engineering, Computer Science, Ocean & Earth Sciences and Modeling & Simulation

Poster Session 1, Honors College, Odu

Undergraduate Research Symposium

Featuring Political Science, Psychology, English, Recreation & Tourism Studies and Biology

Role Of Peripheral Immune Response In Microglia Activation And Regulation Of Brain Chemokine And Proinflammatory Cytokine Responses Induced During Vsv Encephalitis, Christina D. Steel, Kimberly Breving, Susan Tavakoli, Woong-Ki Kim, Larry D. Sanford, Richard P. Ciavarra

Biological Sciences Faculty Publications

We report herein that neuroinvasion by vesicular stomatitis virus (VSV) activates microglia and induces a peripheral dendritic cell (DC)-dependent inflammatory response in the central nervous system (CNS). VSV neuroinvasion rapidly induces multiple brain chemokine and proinflammatory cytokine mRNAs that display bimodal kinetics. Peripheral DC ablation or T cell depletion suppresses the second wave of this response demonstrating that infiltrating T cells are primarily responsible for the bimodal characteristics of this response. The robust infiltrate associated with VSV encephalitis likely depends on sustained production of brain CCL19 and CCR7 expression on infiltrating inflammatory cells. © 2013 Elsevier B.V. All rights reserved.