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The Biotech Century (Book Review), Philip A. Reed Jan 1999

The Biotech Century (Book Review), Philip A. Reed

STEMPS Faculty Publications

No abstract provided.


Pfiesteria Piscicida And Dinoflagellates Similar To Pfiesteria, Harold G. Marshall Jan 1999

Pfiesteria Piscicida And Dinoflagellates Similar To Pfiesteria, Harold G. Marshall

Biological Sciences Faculty Publications

Pfiesteria pisiccida is a microscopic, unicellular organism that is classified as both a mixotrophic and heterotrophic dinoflagellate, which has been associated with both fish deaths and a cause of human illness (Burkholder et al., 1992; Glasglow et al., 1995; Burkholder and Glasgow, 1997). This species possesses a complex life cycle that includes motile forms (e.g. zoospores, gametes, amoebae) and a cyst stage that may remain dormant in the sediment (Burkholder et al, 1995b). Pfiesteria piscicida is known to have toxin and non-toxin producing populations, where cyst transformation into the toxic motile zoospores may be initiated by the presence of certain …


Water Quality Relationships To Concentrations Of Pfiesteria-Like Organisms In Virginia Estuaries For 1998., Everett P. Weber, Harold G. Marshall Jan 1999

Water Quality Relationships To Concentrations Of Pfiesteria-Like Organisms In Virginia Estuaries For 1998., Everett P. Weber, Harold G. Marshall

Biological Sciences Faculty Publications

A series of statistical analyses were performed to identify the relationship between abundance of dinoflagellates grouped as Pfiesteria-like organisms and a set of 25 water quality variables from May through October of 1998 at 41 estuarine locations. Although regions were identified in relation to seasonal density of cells present, there were no strong relationships to specific water quality variables. Factors that may have influenced these results included: a) several species were included in the group analyzed and this composite did not respond as a unit to changing environmental conditions; b) cell concentrations were low and there were a large …


Absorption Efficiencies And Biochemical Fractionation Of Assimilated Compounds In The Cold Water Appendicularian Oikopleura Vanhoeffeni, Alexander B. Bochdansky, Don Deibel, Richard B. Rivkin Dec 1998

Absorption Efficiencies And Biochemical Fractionation Of Assimilated Compounds In The Cold Water Appendicularian Oikopleura Vanhoeffeni, Alexander B. Bochdansky, Don Deibel, Richard B. Rivkin

OES Faculty Publications

Using Ge-68:C-14 dual-labeling, we investigated the absorption efficiency of diatom carbon for the cold water appendicularian Oikopleura vanhoeffeni. The absorption efficiency of bulk carbon (mean = 67%) was not influenced by body size or ingestion rate. For the first time for a pelagic tunicate, food and feces were fractionated into their major biochemical constituents (i.e., low-molecular-weight compounds, lipid, protein, and polysaccharide), allowing calculation of absorption efficiencies for each fraction. Low-molecular-weight compounds and proteins were preferentially absorbed over lipids and polysaccharides. However, predicted C:N ratios of the fecal pellets of O. vanhoeffeni were in the lower range of C:N ratios …


The Effect Of Jogging On Anterior Knee Laxity After Anterior Cruciate Ligament Reconstruction, Fawzi F. Bouzubar Dec 1998

The Effect Of Jogging On Anterior Knee Laxity After Anterior Cruciate Ligament Reconstruction, Fawzi F. Bouzubar

Rehabilitation Sciences Theses & Dissertations

Jogging is commonly performed in the latter stages of the rehabilitation program (2½-3 months) following ACL reconstruction. However, its cyclic loading effect on the ACL graft, 4-6 months after surgery has not been examined. Therefore, the purpose of this study was to examine changes in anterior knee laxity before and after 15 minutes of jogging on the treadmill. Subjects (N=l 1) were 8 males and 3 females (X age= 30.27 ± 4.76 years; heights= 175.7 ± 10.7 cm; weights= 81.1 ± 15.9 kg) with unilateral ACL reconstruction (central 1/3 patellar tendon graft, postoperation range = 4-6 months). Measurements were made …


Accurate Classification Of Juvenile Weakfish Cynoscion Regalis To Estuarine Nursery Areas Based On Chemical Signatures In Otoliths, Simon R. Thorrold, Cynthia M. Jones, Peter K. Swart, Timothy E. Targett Nov 1998

Accurate Classification Of Juvenile Weakfish Cynoscion Regalis To Estuarine Nursery Areas Based On Chemical Signatures In Otoliths, Simon R. Thorrold, Cynthia M. Jones, Peter K. Swart, Timothy E. Targett

OES Faculty Publications

We investigated the ability of trace element and isotopic signatures in otoliths to record the nursery areas of juvenile (young-of-the-year) weakfish Cynoscion regalis from the east coast of the USA. Juvenile C. regalis were captured with otter trawls at multiple sites in Doboy Sound (Georgia), Pamlico Sound (North Carolina), Chesapeake Bay (Virginia), Delaware Bay (Delaware) and Peconic Bay (New York), from July to September 1996. One sagittal otolith from each specimen was assayed for Mg/Ca, Mn/Ca, Sr/Ca and Ba/Ca ratios using inductively coupled plasma mass spectrometry (ICP-MS), while delta 13 C and delta 18 O values from the other sagittal …


Circulation, Vol. 6, No. 1, Center For Coastal Physical Oceanography, Old Dominion University Oct 1998

Circulation, Vol. 6, No. 1, Center For Coastal Physical Oceanography, Old Dominion University

CCPO Circulation

Fall 1998 issue of CCPO Circulation featuring article "Renewed Effort by Mexican Oceanographers to Understand the Dynamics of Coastal Lagoons"


Vertical Profiles Of Virus-Like Particles And Bacteria In The Water Column And Sediments Of Chesapeake Bay, Usa, Lisa A. Drake, Keun-Hyung Choi, A. G. Edward Haskell, Fred C. Dobbs Oct 1998

Vertical Profiles Of Virus-Like Particles And Bacteria In The Water Column And Sediments Of Chesapeake Bay, Usa, Lisa A. Drake, Keun-Hyung Choi, A. G. Edward Haskell, Fred C. Dobbs

OES Faculty Publications

Vertical profiles of virus-like particles (VLPs) and bacteria were determined by near-synoptic sampling through the water column and 15 to 25 cm into the sediment at 5 stations across the mouth of Chesapeake Bay, USA. VLPs were about 10 times more abundant in the pore water (grand mean = 3.6 x 10(8) VLPs ml(-1)) than in the water column (grand mean = 3.8 x 10(7) VLPs ml(-1)). Similarly, bacteria counts were about 3 times higher in the pore water (grand mean = 6.5 x 10(6) bacteria ml(-1)) than in the water column (grand mean = 2.4 x 10(6) bacteria ml(-1)). …


Changes In Small Mammal Community Attributes Associated With Increasing Pine Stand Age In Managed Pine Plantations In Southeastern Virginia, James Douglas Dolan Oct 1998

Changes In Small Mammal Community Attributes Associated With Increasing Pine Stand Age In Managed Pine Plantations In Southeastern Virginia, James Douglas Dolan

Biological Sciences Theses & Dissertations

Loblolly pine plantations were examined at different ages to identify small mammal community attributes in relation to the succession of the plant community. Forest floor and understory plant communities were characterized. Small mammals were collected by Fitch (live) traps and pitfall traps in four age classes during five seasons of study. Fitch live traps and pitfall traps were used in conjunction with one another to obtain the most accurate depiction of the small mammal community. Fitch traps accounted for 65 % of small mammal captures and 7 of 9 species captured. Small mammal abundance and biomass declined with increasing stand …


Radiocarbon From Nuclear Testing Applied To Age Validation Of Black Drum, Pogonias Cromis, Steven E. Campana, Cynthia M. Jones Aug 1998

Radiocarbon From Nuclear Testing Applied To Age Validation Of Black Drum, Pogonias Cromis, Steven E. Campana, Cynthia M. Jones

OES Faculty Publications

Radiocarbon ((14)C) in the world's oceans increased sharply between 1950 and 1970 as a result of the atmospheric testing of nuclear weapons. Through comparison with the (14)C time series reconstructed from atmospheric measurements and marine carbonates, Kalish, in 1993, used the (14)C concentration measured in fish otolith cores as a means of confirming the annulus-based age estimates for some South Pacific fish species. Here we report the pre-and postbomb (14)C chronology of North Atlantic adult black drum (Pogonias cronis), assumed to be between 15 and 42 yr of age on the basis of otolith annulus counts. According to …


Circulation, Vol. 5, No. 4, Center For Coastal Physical Oceanography, Old Dominion University Jul 1998

Circulation, Vol. 5, No. 4, Center For Coastal Physical Oceanography, Old Dominion University

CCPO Circulation

Summer 1998 issue of CCPO Circulation featuring article "Bay Mouth Climatology"


Expression, Isolation And Purification Of Human Zona Pellucida Protein 3, Ting-Fung Chi Jul 1998

Expression, Isolation And Purification Of Human Zona Pellucida Protein 3, Ting-Fung Chi

Theses and Dissertations in Biomedical Sciences

Mammalian fertilization involves interactions of sperm surface receptors with the ligands of the zona pellucida, an extracellular matrix surrounding the ovulated oocytes. In humans, the zona pellucida is composed of three major glycoproteins. One of them, ZP3, participates in the primary sperm binding and in the subsequent triggering of the spermatozoa's acrosome reaction. Studies on the role of this specific protein in the human fertilization process are hampered by the limited amount of available biologically functional proteins.

By use of a pcDNA 3.1(+) expression vector, a transfecting-vector was constructed containing a 1.3 kb histidine tagged hZP3 cDNA. This histidine tagged …


A Psychophysiological Assessment Of The Efficacy Of Event-Related Potentials And Electroencephalogram For Adaptive Task Allocation, Lawrence J. Prinzel Iii Jul 1998

A Psychophysiological Assessment Of The Efficacy Of Event-Related Potentials And Electroencephalogram For Adaptive Task Allocation, Lawrence J. Prinzel Iii

Psychology Theses & Dissertations

The present study was designed to test the efficacy of using Electroencephalogram (EEG) and Event-Related Potentials (ERPs) for making task allocations decisions. Thirty-six participants were randomly assigned to an experimental, yoked, or control group condition. Under the experimental condition, a compensatory tracking task was switched between manual and automatic task modes based upon the participant's EEG. ERPs were also gathered to an auditory, oddball task. Participants in the yoked condition performed the same tasks under the exact sequence of task allocations that participants in the experimental group experienced. The control condition consisted of a random sequence of task allocations that …


Effect Of Pulsed Electric Fields On Aquatic Nuisance Species, Amr Abou-Ghazala Jul 1998

Effect Of Pulsed Electric Fields On Aquatic Nuisance Species, Amr Abou-Ghazala

Electrical & Computer Engineering Theses & Dissertations

Clinical and theoretical evidence indicate that electric fields have biological effects ranging from recoverable disturbance to mortality induction depending on the field parameters and time of exposure. In this thesis, the effect of electrical field in pulsed form on aquatic nuisance species is investigated. Pulse parameters in terms of amplitude, width, shape, and repetition rate that stimulate the species to desirable levels are to be defined. Applying the electrical pulses with appropriate parameters to stun aquatic nuisance species entering marine cooling systems will prevent it from attaching to pipe walls. The use of electrical fields to seek efficient, environmentally friendly, …


An Injection Modelocked Titanium-Sapphire Laser, James C. Hovater Jul 1998

An Injection Modelocked Titanium-Sapphire Laser, James C. Hovater

Electrical & Computer Engineering Theses & Dissertations

I have investigated the possibility of using an injection modelocked Ti-sapphire laser as a illumination source for GaAs photocathodes. A commercial Ti-sapphire laser was modified to accept a seed pulse from a gain-switched diode laser. Modelocked operation was obtained through gain modulation within the Ti-sapphire crystal as a result of injection seeding with a modelocked pulse train from a gain-switched diode laser. The Ti-sapphire laser essentially becomes a pulse amplifier for the diode laser. Unlike conventional modelocked lasers, the pulse repetition rate of this laser can be discretely varied by setting the seed laser repetition rate equal to multiples of …


The Effect Of Ethanol And Hypoglycemia On Rat Performance In The Radial Arm Maze, Monica Ann Gaffney Jul 1998

The Effect Of Ethanol And Hypoglycemia On Rat Performance In The Radial Arm Maze, Monica Ann Gaffney

Psychology Theses & Dissertations

Both hypoglycemia (HG) and ethanol (ETH) intoxication can cause serious impairment in physiological and psychological functioning. Their combination could cause more severe cognitive impairment than either condition alone. This experiment investigated the effects of hypoglycemia, ethanol intoxication, and their combination on rat radial arm maze performance. Eleven male rats were trained to a stable, low error rate performance in achieving food rewards in an eight arm radial arm-maze. Rats were then given either insulin (2 units/kg) or saline in combination with ETH doses of 250, 500, 1000, or 1500 mg/kg 20 minutes prior to the maze run. Treatment order was …


Development Of Fluorescent Techniques In The Kinetic Characterization Of Reverse Transcriptase, Kevin Kevin Howerton Jul 1998

Development Of Fluorescent Techniques In The Kinetic Characterization Of Reverse Transcriptase, Kevin Kevin Howerton

Chemistry & Biochemistry Theses & Dissertations

Reverse transcriptase (RT) is an RNA-directed DNA polymerase isolated from human immunodeficiency virus (HIV) and other retroviruses. It has been the primary target for anti-HIV research since the discovery of its vital role in the retroviral life-cycle. The conventional method for carrying out kinetic characterization and inhibition studies of reverse transcriptase involves the use of radioactive materials. Although this method is effective, it is both time consuming, due to a necessary repeated washing step, and hazardous to the worker and environment. Furthermore, strict laws limit the use of radioactive materials to licensed workers and laboratories. In response to these concerns, …


Shoreline Change Modeling As A Tool In Coastal Environmental Management, Jorge Espinoza Amaguana Jul 1998

Shoreline Change Modeling As A Tool In Coastal Environmental Management, Jorge Espinoza Amaguana

Civil & Environmental Engineering Theses & Dissertations

The one-line numerical model GENESIS has been calibrated to evaluate its performance as a tool in providing insights into the physical components to manage the coastal environment. To calibrate the model, physical environmental data, literature research, and computer modeling methodologies were utilized in addressing the objectives of this thesis. The model was applied at three beaches of the Virginia Beach City with different man-made structures by using the actual field wave data for wave year J 997. Waves are the main environmental component affecting the coastal system; however, additional environmental data and the best engineering decision were used as model …


Determination Of The N-Terminal Amino Acid Residues On Polypeptides In Secondary Wastewaters, Edward L. Creecy Jul 1998

Determination Of The N-Terminal Amino Acid Residues On Polypeptides In Secondary Wastewaters, Edward L. Creecy

Chemistry & Biochemistry Theses & Dissertations

The N-terminal amino acid residues on polypeptides and proteins were determined in wastewaters prior to chlorination. The terminal amino groups'ere first derivatized with the well known derivatizing agent dansyl chloride, and then the resulting dansyl amino acid hydrolyzed from the peptide chain by a propionic acid/ hydrochloric acid mixture. The resulting dansyl amino acids were then separated and detected using reversed phase high performance liquid chromatography with fluorescence detection. The majority of N-terminal residues detected were the more polar amino acids. Concentrations ranged from 1 x 10-10 to 3 x 10-7 moles/liter. It is suggested that the shorter …


Efficacy Of AllowashTm Solution In Solubilization Of Bone Marrow, Alyce Marie Linthurst Jul 1998

Efficacy Of AllowashTm Solution In Solubilization Of Bone Marrow, Alyce Marie Linthurst

Biological Sciences Theses & Dissertations

LifeNet currently cleans allograft bone utilizing AllowashTM Technology, which encompasses the use of a closed continuous circulation chamber to remove bone marrow by flushing it with AllowashTM Solution for a prescribed time and temperature after which, it is rinsed with various solutions to remove residual detergent that could be toxic to the recipient. A portion of this process employs AllowashTM Solution to improve the solubilization and removal of protein and cellular elements in the red bone marrow. This study examines the effectiveness of AllowashTM Solution in comparison to its component detergents Nonidet P40, Nonoxynol 9 and …


Measurement Of Hospital Performance: Environmental And Organizational Factors Associated With Cost, Debra Kay Dierksmeier Anderson Jul 1998

Measurement Of Hospital Performance: Environmental And Organizational Factors Associated With Cost, Debra Kay Dierksmeier Anderson

Health Services Research Dissertations

As U.S. health care expenditures top the $1 trillion mark, there is increased interest in measuring the performance of health care providers. For bottom line oriented payors such as government and business, the focus is on measuring cost. As hospitals account for over one-third of health care expenses, hospital cost per admission is a common measure of performance.

Many environmental and organizational factors come into play in determining hospital cost per admission. This research examines several of these factors, using Raymond Zammuto's model of organizational effectiveness assessment. Using Zammuto's framework, this research looks at the relationship of social, physical, and …


Characterization Of The Biological Functions Of Human Recombinant Zona Pellucida Protein 3, Yu Wen Juan Jul 1998

Characterization Of The Biological Functions Of Human Recombinant Zona Pellucida Protein 3, Yu Wen Juan

Theses and Dissertations in Biomedical Sciences

Recombinant human zona pellucida protein 3 (rhZP3), expressed. isolated and purified from PA-1 cells, is characterized for its biological activity and the role in the signal transduction pathway. Characterization of the biological activity of rhZP3 was detected by hemizona assay and immunofluorescence staining of acrosome reaction The results indicated that rhZP3 exhibited an inhibition in the binding assay (HZI 43.6 +/-3.3; n = 9; 30 ng/mL rhZP3) and induction of acrosome reaction (198.6% +/- 77.2% increase from baseline; n = 29; 30 ng/mL rhZP3). It was further confirmed by the transmission electron microscopy that there was no difference in morphology …


The Relationship Of Antifat Attitudes To Other Prejudicial Attitudes: Construct Validation Of The Antifat Attitudes Test, Mark S. Perez-Lopez Jul 1998

The Relationship Of Antifat Attitudes To Other Prejudicial Attitudes: Construct Validation Of The Antifat Attitudes Test, Mark S. Perez-Lopez

Psychology Theses & Dissertations

There are many negative effects of obesity in our society. As a result, a new measure of antifat attitudes was developed. This study examined the construct, discriminant, and convergent validity of the Antifat Attitudes Test by relating antifat attitudes to racism, sexism, and homophobia.

Participants included 179 college undergraduate students. Multiple regression analyses revealed significant contributions of sex-role egalitarianism, racism, masculine ideology, body mass, and social desirability in the prediction of antifat attitudes. Several one-way analyses of variance revealed that men expressed stronger antifat attitudes than women and African-Americans were more accepting of fat individuals than were Whites. Additionally, androgynous …


Leukemia Inhibitory Factor (Lif): Murine Preimplantation Embryo Development, Implantation Rates, And Skeletal Development, Michael Hayes Mitchell Jul 1998

Leukemia Inhibitory Factor (Lif): Murine Preimplantation Embryo Development, Implantation Rates, And Skeletal Development, Michael Hayes Mitchell

Theses and Dissertations in Biomedical Sciences

Leukemia inhibitory factor (LIF) is a pleiotropic cytokine which demonstrates perplexing physiological effects. It has been demonstrated that LIF is essential for implantation in mice. Little is known relating to the manner by which LIF effects pre-implantation and post-implantation development. The objectives of this project were to determine the effects LIF on pre-implantation development, to determine the effects that it may have on implantation rates, successful pregnancy rates, and resorption rates, and to determine the effects that LIF has on the skeletal development of mice. For the embryo transfer experiments, embryos were exposed to test compounds in the transfer medium …


Circulation, Vol. 5, No. 3, Center For Coastal Physical Oceanography, Old Dominion University, Louis Codispoti, Steve Gaurin Apr 1998

Circulation, Vol. 5, No. 3, Center For Coastal Physical Oceanography, Old Dominion University, Louis Codispoti, Steve Gaurin

CCPO Circulation

Spring 1998 issue of CCPO Circulation CCPO Circulation featuring article "Steve and Lou's Excellent Antarctic Adventure: Anectodal Observations of Birds, Ocean, and Human Zaniness at the Polar Front"


Mathematical Models Of Tumors And Their Remote Metastases, Carryn Bellomo Apr 1998

Mathematical Models Of Tumors And Their Remote Metastases, Carryn Bellomo

Mathematics & Statistics Theses & Dissertations

Clinical observations and indications in the literature have led us to investigate several models of tumors. For example, it has been shown that a tumor has the ability to send out anti-growth factors, or inhibitors, to keep its remote metastases from growing. Thus, we model the depleting effect of such a growth inhibitor after the removal of the primary tumor (thus removing the source) as a function of time t and distance from the original tumor r.

It has also been shown clinically that oxygen and glucose are nutrients critical to the survival and growth of tumors. Thus, we model …


Studies On The Biology Of Striga Aspera (Scrophulariaceae) In Nigeria, Emmanuel Izaka Aigbokhan Apr 1998

Studies On The Biology Of Striga Aspera (Scrophulariaceae) In Nigeria, Emmanuel Izaka Aigbokhan

Biological Sciences Theses & Dissertations

Studies on Striga aspera are few and little information exists on its relationship with the morphologically similar and much studied S. hermonthica. Both species are sympatric in West Africa and if they hybridize, may serve as virulent gene reservoirs for each other.

The primary focus of this study was on the biology of S. aspera in Nigeria. The research focussed on its distribution, phenology, cytology, hybridization, seed dormancy, viability and germination in relation to S. hermonthica. Related studies involving the hybrids include genetic and morphological variability, pathogenicity and the simultaneous dual infection of a maize plant by both species.

In …


Material Evaluation By Pulsed Diode Laser Optoacoustics, Xiaodong Xu Apr 1998

Material Evaluation By Pulsed Diode Laser Optoacoustics, Xiaodong Xu

Electrical & Computer Engineering Theses & Dissertations

Pulsed diode laser optoacoustic diagnostics were carried out to characterize solid sample materials. The apparatus developed is compact, portable, cost-effective and therefore very promising for both industrial as well as laboratory applications. To our knowledge, this is the first time that optoacoustic characterization and measurement have been performed with a diode laser. The method was successfully applied to measure the thickness of a multilayer structure non-intrusively. Internal cracks of the material were detected by this technique.

A theory for optoacoustic signal generation, propagation and detection is given. A numerical analysis technique is developed to solve for the expected signal. In …


Electrocortical Output And Hemispheric Contributions To The Alert State During A Sustained Attention Task, Treven Curtis Pickett Apr 1998

Electrocortical Output And Hemispheric Contributions To The Alert State During A Sustained Attention Task, Treven Curtis Pickett

Psychology Theses & Dissertations

This study investigated the relative electrocortical contributions of specified cerebral locations and the potential motoric influence of handedness in a biocybernetic feedback environment. Thirty six right-handed subjects engaged in two sixteen minute trials of a compensatory tracking task by guiding (via a joystick) a circle over a stationary target presented on a computer screen, performing one trial with their preferred (right) and one using their non-preferred (left) hand.

For each subject, a Macintosh computer interpreted electrocortical activity through an engagement index (20*beta/(alpha+theta)) and changed the task mode, i.e. manual (subject guides the task) or automatic (computer guides the task) as …


A Needs Assessment For A Distance Education Baccalaureate Degree Completion Program For Associate Degree Level Dental Hygienist, Joan Gugino Ellison Apr 1998

A Needs Assessment For A Distance Education Baccalaureate Degree Completion Program For Associate Degree Level Dental Hygienist, Joan Gugino Ellison

Dental Hygiene Theses & Dissertations

The purpose of this descriptive research was to determine the need for a distance education program for geographically dispersed dental hygienists to complete a baccalaureate degree program in dental hygiene. The sample consisted of randomly selected licensed dental hygienists in the Commonwealth of Virginia. A self-designed instrument, titled The Distance Education for a Dental Hygiene Degree Completion Program Questionnaire, was mailed to the study participants after establishing validity and reliability. The questionnaire asked participants to provide information concerning personal demographics, educational background, and interest in completing a dental hygiene baccalaureate degree via distance education. Frequencies, percentages, crosstabulations, chi-square test …