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Development Of Free-Label Sensing In Plastic Microfluidic Platforms Using Pulsed Streaming Potentials (Psp), Vera Fernando Luna May 2011

Development Of Free-Label Sensing In Plastic Microfluidic Platforms Using Pulsed Streaming Potentials (Psp), Vera Fernando Luna

Theses and Dissertations

This work deals with the development of a new label-free detection technique called Pulsed Streaming Potential (PSP). Its novelty relies on the adaptation of a classical electrokinetic phenomenon (streaming potential) into a tool which can evaluate molecular interplay in label-free fashion. Implementation of PSP to microfluidic platforms allowed the label-free sensing of binding events to plastic (modified and unmodified) surfaces. It was demonstrated the use of real time PSP in plastic microfluidic platforms for determination of kinetic parameters of the interaction of proteins and plastic surfaces. Moreover, initial change of PSP after adsorption of proteins showed to be proportional to …

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Social Support Received Online And Offline By Individuals Diagnosed With Cancer, Jessye Cohen May 2011

Social Support Received Online And Offline By Individuals Diagnosed With Cancer, Jessye Cohen

Theses and Dissertations

Life after treatment for cancer has become a primary focus for health service provider communities as the number of individuals living longer grows. The medical and psychosocial needs of cancer survivors have been prominent in the popular and scientific literature. A major focus for psychologists has been the relationships and social support networks of individuals diagnosed with cancer. The current study explored a recent phenomenon within this realm, the use of Internet resources for online support. The purpose of this study was to compare social support received online and social support received offline among people diagnosed with cancer who use …

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A Framework For Digital Emotions, Meghan Rosatelli May 2011

A Framework For Digital Emotions, Meghan Rosatelli

Theses and Dissertations

As new media become more ubiquitous, our emotional experiences in digital space are increasing exponentially as well. While there is much talk of “affective” computing and “affective” new media art, a disconnect exists between networked emotions and the popular media that they inhabit. This research presents a theoretical framework for assessing “digital emotions”—a term that describes the feedback process between digital technologies and the body with respect to short, networked inscriptions of emotion and the (re)experience of those inscriptions within the body and through digital space. Digital emotions display five basic characteristics that can be applied to a variety of …

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The Superfund Program Past And Present Funding Implications, Nicole Franklin May 2011

The Superfund Program Past And Present Funding Implications, Nicole Franklin

Theses and Dissertations

The present research examines the impact of not reauthorizing the Superfund taxes on the operations of the program. EPA NPL site status data were obtained from the EPA CERCLIS database for analysis in this study. Data were selected for the fiscal years 1981 to 2009 in four NPL listing status categories: proposal to the NPL, final NPL listing, deletion from the NPL, and achievement of construction completion. Since the Superfund tax expired in 1995, data from the 1981 to 1995 fiscal years and data from the 1996 to 2009 fiscal years were analyzed to determine if there were mean differences …

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Application Of Pharmacometric Methods To Improve Pediatric Drug Development, Mallika Lala May 2011

Application Of Pharmacometric Methods To Improve Pediatric Drug Development, Mallika Lala

Theses and Dissertations

Pharmacometrics is a quantitative science that is rapidly changing the landscape of drug development, and particularly so for the pediatric population. The motivation behind the research underlying this dissertation is to contribute towards the improvement of pediatric drug development by the astute application of pharmacometric methods. Two distinct research areas have been focused upon: 1- improving pediatric pharmacokinetic (PK) trial design and 2- improving pediatric dosing of warfarin by using a genetics-based dosing regimen. The first project examined in detail the feasibility of and simulation-based methodology for implementing a recent regulatory PK quality standard. The focus was on designing pediatric …

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Craft Cyborg, Laina Seay May 2011

Craft Cyborg, Laina Seay

Theses and Dissertations

By merging the ancient associations that clay has with the human form and prosthetic science I question the relevancy and role of the human body in the future. As prosthetics heighten the awareness of the body through absence these additive limbs further this relevancy by presence. With greater advances in genetic engineering and plastic surgery biology will no longer dominate and these ridged clay extensions could become flesh.

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Analysis Of The Mechanism By Which Ykl-40 Promotes Glioma Cell Migration, Bahiya Osrah May 2011

Analysis Of The Mechanism By Which Ykl-40 Promotes Glioma Cell Migration, Bahiya Osrah

Theses and Dissertations

This thesis elucidates the crucial role of YKL-40 in enhancing glioma cell migration and invasion in vitro. Increased levels of YKL-40 are specifically associated with the increased invasive capacity of glioma multiforme (GBM) tumors and lower survival rate of GBM patients. In order to examine the effects of YKL-40 on the migration and invasion of GBM cells, we overexpressed YKL-40 in three different glioma cell lines. The overexpression of YKL-40 significantly enhanced glioma cells migration and invasion in vitro and also increased ERK phosphorylation, which is believed to enhance glioma cell survival, and invasiveness. Although receptors for YKL-40 are still …

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Comparison Of Adhesion Of Gutta Percha/Ah Plus® And Resilon/Epiphany® Se™ After A Final Rinse With Different Concentrations Of Ethanol, Suren Paravyan May 2011

Comparison Of Adhesion Of Gutta Percha/Ah Plus® And Resilon/Epiphany® Se™ After A Final Rinse With Different Concentrations Of Ethanol, Suren Paravyan

Theses and Dissertations

The purpose of this study was to evaluate effect of final rinse of ethanol on bond strength in teeth obturated with Gutta Percha (GP)/AH Plus® or Resilon/Epiphany®SE™. Thirty-two extracted human anterior teeth were shaped to size 30, 0.06 taper and subjected to an identical irrigation protocol. Specimens were randomly divided into eight groups according to final irrigating solution (saline, 70%, 95%, 100% ethanol) and obturation material. Two millimeter thick slices were obtained by sectioning each obturated root. Bond strength was determined using micropush-out assay. Data was analyzed using Student’s t-test. Obturation with GP/AH Plus® formed a statistically significant stronger bond …

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Comparison Of Epiphany® And Ah-Plus® Root Canal Sealer Penetration Of Dentinal Tubules: A Sem Study, Kalisha Jordan May 2011

Comparison Of Epiphany® And Ah-Plus® Root Canal Sealer Penetration Of Dentinal Tubules: A Sem Study, Kalisha Jordan

Theses and Dissertations

The purpose of this study was to evaluate the effect of a final rinse of ethanol on depth of sealer penetration in teeth obturated with Gutta Percha (GP)/AH-Plus® (Dentsply, De Trey GmbH, Konstanz, Germany) or Resilon/Epiphany® SE™ (Pentron Clinical Technologies, LLC, Wallingford, CT). Extracted human anterior teeth (n= 32) were shaped to size 30, 0.06 taper using nickel-titanium rotary files and subjected to an identical irrigation protocol. Specimens were randomly divided into eight groups according to final irrigating solution (saline, 70%, 95%, or 100% ethanol) and obturation material (GP/AH-Plus® or Resilon/EpiphanyÒ SE™). A 2mm thick slice was obtained by sectioning …

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Vapor Transport And Aerosol Dynamics In The Respiratory Airways, Geng Tian May 2011

Vapor Transport And Aerosol Dynamics In The Respiratory Airways, Geng Tian

Theses and Dissertations

Predicting vapor transport and aerosol dynamics in the respiratory airways is important for analyzing both environmental exposure and respiratory drug delivery. A large number of analytical models, computational studies, and experiments on vapor and aerosol transport in the respiratory tract have been conducted previously. However, a number of critical questions remain unanswered. In this study, computational fluid dynamics (CFD) is primarily employed with frequent comparisons to existing and new experimental data sets to address previously unanswered issues related to the transport of vapors and aerosol in the respiratory tract. The three objectives of this study are further described below. Objective …

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A Parallel Genetic Algorithm For Placement And Routing On Cloud Computing Platforms, Jacob A. Berlier May 2011

A Parallel Genetic Algorithm For Placement And Routing On Cloud Computing Platforms, Jacob A. Berlier

Theses and Dissertations

The design and implementation of today's most advanced VLSI circuits and multi-layer printed circuit boards would not be possible without automated design tools that assist with the placement of components and the routing of connections between these components. In this work, we investigate how placement and routing can be implemented and accelerated using cloud computing resources. A parallel genetic algorithm approach is used to optimize component placement and the routing order supplied to a Lee's algorithm maze router. A study of mutation rate, dominance rate, and population size is presented to suggest favorable parameter values for arbitrary-sized printed circuit board …

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Analysis Of Nfi-X3 And Stat3 Interaction And Its Functions, Etsegenet Tizazu May 2011

Analysis Of Nfi-X3 And Stat3 Interaction And Its Functions, Etsegenet Tizazu

Theses and Dissertations

YKL-40 is a secreted protein that is highly up-regulated in malignant glioblastoma (GBM). Its expression is correlated with the invasive nature of GBMs and poor diagnosis of patients (Nigro et al., 2005). Previous research has shown that in astrocytes and GBM cells, YKL-40 expression is regulated by two transcription factors, NFI-X3 and STAT3, which form a complex with each other (Singh et al., 2011). Here, we show that the N-terminal domain of NFI-X3 is sufficient and required for its interaction with STAT3. We also show that the DNA-binding domain of NFI-X3 is required to induce YKL-40 expression. Thus, the interaction …

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Computational Modeling Of Mulitsensory Processing Using Network Of Spiking Neurons, Hun Ki Lim May 2011

Computational Modeling Of Mulitsensory Processing Using Network Of Spiking Neurons, Hun Ki Lim

Theses and Dissertations

Multisensory processing in the brain underlies a wide variety of perceptual phenomena, but little is known about the underlying mechanisms of how multisensory neurons are generated and how the neurons integrate sensory information from environmental events. This lack of knowledge is due to the difficulty of biological experiments to manipulate and test the characteristics of multisensory processing. By using a computational model of multisensory processing this research seeks to provide insight into the mechanisms of multisensory processing. From a computational perspective, modeling of brain functions involves not only the computational model itself but also the conceptual definition of the brain …

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The Impact Of Overt And Relational Victimization On Adolescents' Well Being: Moderating Effects Of Ethnicity At The Individual And School Level, Krista Mehari May 2011

The Impact Of Overt And Relational Victimization On Adolescents' Well Being: Moderating Effects Of Ethnicity At The Individual And School Level, Krista Mehari

Theses and Dissertations

The sociocultural influence of ethnicity on peer victimization among youth has received little attention in the research literature. Individual ethnicity within school ethnic composition may influence the frequency of victimization and the effect of victimization on adolescents’ well being. The current study investigated these issues using a data set of 5,581 sixth grade students attending 37 schools located in four sites. Multilevel models examined the extent to which individual ethnicity within school ethnic composition influenced the frequency and impact of overt and relational victimization on changes in life satisfaction. Ethnic differences were found in the frequency of victimization, but these …

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Changes In Leaf Morphology, Photosynthesis And Nitrogen Content In Two Coastal Shrubs, Elizabeth Kost May 2011

Changes In Leaf Morphology, Photosynthesis And Nitrogen Content In Two Coastal Shrubs, Elizabeth Kost

Theses and Dissertations

It is important to understand mechanisms that facilitate expansion of two common shrubs, Morella cerifera and Baccharis halimifolia in coastal environments. The purpose of my study was to investigate the physiological and structural changes that occur as leaves age. Photosynthesis, incident light, chlorophyll, and leaf C:N ratios were quantified for young, intermediate, and old leaves (distal, central and proximal leaves, respectively). Leaf structural differences were also compared. Leaves did not change morphologically with age. Light decreased with leaf age and during winter months. Photosynthesis showed no seasonal or age related patterns. Chlorophyll increased initially and then declined with age due …

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Turning To The Bottle For Answers: Identifying Racial Differences In Predictors Of Risk Drinking Among College Women, Melody Mickens May 2011

Turning To The Bottle For Answers: Identifying Racial Differences In Predictors Of Risk Drinking Among College Women, Melody Mickens

Theses and Dissertations

Epidemiological data suggest that alcohol use and related problems have increased among college women. The current study examined psychosocial predictors of risk drinking in a sample of college women (N=360), whether race moderated this relationship. Potential predictors included: daily smoker; premenstrual syndrome (PMS) symptom severity; age at first alcohol use, negative affect, parental history of alcohol problems and minority status. Analyses found that somatic PMS symptom severity score, age of first alcohol use, daily smoking, age of first alcohol use and non-minority status were related. Findings suggest that minority group membership was associated with low risk drinking, while somatic PMS …

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Cumulative Risks To Eastern Oysters, Crassostrea Virginica In The James River, Va, Vrushali Lele May 2011

Cumulative Risks To Eastern Oysters, Crassostrea Virginica In The James River, Va, Vrushali Lele

Theses and Dissertations

In an effort to apply Cumulative Risk Assessment (CRA) as developed by the U.S. EPA, the present study investigates the cumulative risks to Eastern oysters due to multiple stressors such as salinity, temperature and oxygen and carbon dioxide. I also compared the effectiveness of the Hazard Quotient Method (HQ) in CRA. Ambient conditions in the James River, VA were obtained from the Virginia DEQ database and respiratory responses were estimated using values from the literature. The multiple environmental stresses are evaluated using a probabilistic analysis that combines the environmental conditions. It was concluded that salinity was the most influential stressor …

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A Novel Bioactive Glass-Enhanced Orthodontic Bonding Resin: A Shear Bond Strength Study, Cole Johnson May 2011

A Novel Bioactive Glass-Enhanced Orthodontic Bonding Resin: A Shear Bond Strength Study, Cole Johnson

Theses and Dissertations

Enamel decalcification caused by poor oral hygiene is a significant problem in orthodontics. Bioactive glass-containing resins have been shown to release Ca2+ ions into surrounding solution. The purpose of this study was to determine the shear bond strength of four different compositions of orthodontic resin prepared with bioactive glass (N=20). Premolars were bonded using one of four BAG-BOND compositions. Brackets were debonded and ARI scores were given. The mean shear bond strength was 7.23 ± 2.47 MPa (62 BAG-BOND), 8.25 ± 2.87 MPa (65 BAG-BOND), 8.78 ± 3.08 MPa (81BAG-BOND) and 5.80 ± 2.27 MPa (85 BAG-BOND). 65 and 81 …

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Commonwealth Times 2011-05-02 May 2011

Commonwealth Times 2011-05-02

Commonwealth Times, 1969-

No abstract provided.

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The Natural Polyphenol Resveratrol Potentiates The Lethality Of Hdac Inhibitors In Acute Myelogenous Leukemia Cells Through Multiple Mechanisms., Alae Abod Yaseen May 2011

The Natural Polyphenol Resveratrol Potentiates The Lethality Of Hdac Inhibitors In Acute Myelogenous Leukemia Cells Through Multiple Mechanisms., Alae Abod Yaseen

Theses and Dissertations

This study examined the mechanisms underlying the interactions between the natural polyphenol Resveratrol and HDAC inhibitors in both U937 myelomonocytic leukemia cell line and blood samples from AML patients and normal cord blood. Simultaneous exposure to Resveratrol and HDAC inhibitors (Vorinostat-SAHA or Panobinostat-LBH589) resulted in potentiating the lethality caused by any single agent of the combination, this interaction found to be synergistic at multiple concentrations. Exposing U937 cells to minimal toxic doses of Resveratrol and HDACIs results in release of mitochondrial pro-apoptotic proteins AIF and cytochrome c, pro-apoptotic caspase activation especially caspase-8, and induction of DNA damage. These events were …

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Defining The Bacterial Flora Of Periodontal Pockets In Chronic Periodontitis Patients, Rafael Rodriguez May 2011

Defining The Bacterial Flora Of Periodontal Pockets In Chronic Periodontitis Patients, Rafael Rodriguez

Theses and Dissertations

PURPOSE: The purpose of this study is to describe the subgingival bacterial biodiversity in untreated chronic periodontitis patients through the use of next generation 16S rRNA molecular analysis, and to determine similarities or differences between deep and shallow pockets within the same patients. METHODS: The analysis involved paired subgingival plaque samples from 24 subjects diagnosed with Generalized Moderate to Severe Chronic Periodontitis. One sample was selected from a single site having a probing depth >5 mm (i.e. Deep Site), and the other from a site with a probing depth <3mm (i.e. Shallow Site) within each subject. Bacterial DNA amplification of the V4-V6 region of the 16S rRNA was performed. The amplicons were sequenced via 454 Roche Genome Sequencer FLX System. The identified sequences were evaluated, and then compared to calculated false discovery rates. RESULTS: A total of 119 independent microbial genera were identified within the samples analyzed. Seven genera were identified to be statistically significant (p<0.05) in their association to deep or shallow sites following t-test and boot strap randomization: Actinomyces (p=0.004), Methylobacterium (p=0.028), Veillonella (p=0.028), and Rothia (p=0.038), and Streptococcus (p=0.033) in Shallow sites; while Mycoplasma (p=0.007) and Fusobacterium (p=0.016) were associated with deep sites. However, taking into account the calculated false discovery rates, it is suggested that none of the 119 microbial genera identified in this study were significantly associated with either deep nor shallow sites. CONCLUSION: The microbial genera identified within this study to be associated with deep and shallow sites follows the traditional pattern anticipated from the literature. However, the calculated false discovery rates suggest that these results may have occurred by chance and not due to a true difference.

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What Are The Educational Aspirations Of African American Males Raised In Mother-Only Households?, Patsy Chavis May 2011

What Are The Educational Aspirations Of African American Males Raised In Mother-Only Households?, Patsy Chavis

Theses and Dissertations

The purpose of this study is to examine the relationship of Black males being raised in a mother-only household and their career aspirations. The absence of the father in a home stands at the forefront as the cause of family dysfunction, which subsequently leads to the destruction of many hopes and dreams of the Black male.Is a mother-only household a preconceived environment for failure for the Black male?

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Ink (2011-05) May 2011

Ink (2011-05)

Ink, 2008-

The student-run features magazine covering the fashion, art, music and culture worlds at VCU and in Richmond. Published annually in print and updated regularly online.

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The Influence Of Family Structure And Transitions On Parenting, Income, Residential Mobility, And Substance Initiation In Early Adolescence: A Comparison Of Caucasian And African American Youth, Sally Mays Apr 2011

The Influence Of Family Structure And Transitions On Parenting, Income, Residential Mobility, And Substance Initiation In Early Adolescence: A Comparison Of Caucasian And African American Youth, Sally Mays

Theses and Dissertations

The effect of family structure on youth adjustment has received increasing attention as historical trends in single parenting, divorce, remarriage, and cohabitation with partners and extended family members have produced a diverse constellation of structures. African American youth are less likely than Caucasian youth to live in an “intact” family. Links between family structure and a variety of indices of youth adjustment have been established, although a relatively understudied outcome is that of substance initiation, despite its association with dependence and other negative sequelae. The dynamic effect of transitions has additionally been less studied than the static effect of structure. …

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Discriminative Stimulus Properties Of 3-Substituent Rimonabant Analogs, D. Matthew Walentiny Apr 2011

Discriminative Stimulus Properties Of 3-Substituent Rimonabant Analogs, D. Matthew Walentiny

Theses and Dissertations

Cannabinoid agonists (e.g., THC) dose-dependently decrease locomotor activity and body temperature and produce antinociception and catalepsy. Drugs that produce this tetrad of effects within a limited dose range are likely to function as CB1 receptor agonists. A structure activity relationship study from our laboratory investigating analogs of the CB1 antagonist rimonabant revealed that certain alterations in the 3-substituent of rimonabant’s pyrazole core conferred agonist-like properties in the tetrad. Interestingly, these effects were present in CB1 -/- mice, and were not reversed by rimonabant in wild-type mice. The present study evaluated two novel 3-substituent rimonabant analogs, O-6629 and O-6658 in the …

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Phytoremediation Of Pcb Contaminated Soil: Effectiveness And Regulatory Policy, Nathan Pinsker Apr 2011

Phytoremediation Of Pcb Contaminated Soil: Effectiveness And Regulatory Policy, Nathan Pinsker

Theses and Dissertations

The purpose of this paper was to combine available peer-reviewed literature on PCB phytoremediation and make direct comparisons using ANCOVA statistics in order to determine if and what plants are presently a viable option for the remediation of PCB contaminated soils. Pumpkin (Curbita pepo cv Howden) consistently had the top root and shoot concentrations, as well as total plant accumulation. Their consistency shows that they can be reliable in the field and the most viable option. Tall fescue and sedge were also top contenders. Due to the small sample size for many plants and accounting for several confounding variables, very …

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Sulfatide Is Required For Organization Of The Paranode In The Myelinated Axon In The Peripheral Nervous System, Eva Kwong Apr 2011

Sulfatide Is Required For Organization Of The Paranode In The Myelinated Axon In The Peripheral Nervous System, Eva Kwong

Theses and Dissertations

Myelin facilitates the timely, efficient conduction of action potentials along axons. Made by Schwann cells (SCs) in the PNS, myelin is unique in that it is composed of a high percentage of lipids, particularly galactolipids. Sulfatide, one such galactolipid, is made by cerebroside sulfotransferase (CST) and has been shown to play a role in organizing paranodal domains in myelinated axons. However less is known regarding the involvement of sulfatide in the establishment and maintenance of the node, of particular interest as it is responsible for the potentiation of action potentials along the axon. Using immunohistochemical and, to a lesser extent, …

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Role Of Two-Component System Response Regulators In Virulence Of Streptococcus Pneumoniae Tigr4 In Infective Endocarditis, My Trinh Apr 2011

Role Of Two-Component System Response Regulators In Virulence Of Streptococcus Pneumoniae Tigr4 In Infective Endocarditis, My Trinh

Theses and Dissertations

Streptococci resident in the oral cavity have been linked to infective endocarditis (IE). While viridans streptococci are commonly studied and associated with IE, less research has been focused on Streptococcus pneumoniae. Two-component systems (TCSs), consisting of a histidine kinase (HK) protein and response regulator (RR) protein, are bacterial signaling systems that may mediate S. pneumoniae TIGR4 strain virulence in IE. To test this hypothesis, TCS RR mutants of TIGR4 were examined in vivo through use of rabbit models. There were 14 RR proteins identified and 13 RR mutants synthesized because SP_1227 was found to be essential. The requirement of the …

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Determining The Effect Of Double-Stranded Rna Treatment In Ovarian Cancer, Charlotte Roberts Apr 2011

Determining The Effect Of Double-Stranded Rna Treatment In Ovarian Cancer, Charlotte Roberts

Theses and Dissertations

DETERMINING THE EFFECT OF DOUBLE-STRANDED RNA TREATMENT IN OVARIAN CANCER By Charlotte Faye Roberts, B.A. A thesis submitted in partial fulfillment of the requirements for the degree of Masters of Science in Biochemistry at Virginia Commonwealth University.Virginia Commonwealth University, 2011Major Director: Jessica K. Bell, Ph.D.Assistant Professor, Department of Biochemistry & Molecular Biology. Epithelial ovarian cancer is a lethal gynecological malignancy. Due to its asymptomatic nature it is typically detected in the latter metastatic stages. Standard treatment protocol involves surgical cytoreduction, followed by a combination of taxane and platinum-based chemotherapeutics. Initially this treatment is successful however, most patients face recurring tumors …

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Trends In Dental Care For Individuals With Ectodermal Dysplasia, Justin Edwards Apr 2011

Trends In Dental Care For Individuals With Ectodermal Dysplasia, Justin Edwards

Theses and Dissertations

Purpose: The specific aim of this study is to evaluate the trends in dental health care for individuals with ectodermal dysplasia. Methods: This was a cross sectional analysis of subjects recruited through the National Foundation of Ectodermal Dysplasia (NFED). From 1997 to 2000, individuals with ectodermal dysplasia or their caregiver (if the individuals were too young to selfreport) voluntarily completed questionnaires. The questionnaire consisted of 37 items consisting of demographics, ectodermal dysplasia diagnosis, access to dental care, level of dental utilization, and type of dental services received. Descriptive statistics were used in addition to ANOVA analyses to evaluate the changing …

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