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Spatial And Temporal Distribution Of Larval Fishes In A Large Tidal River., Harold Seelig Apr 2010

Spatial And Temporal Distribution Of Larval Fishes In A Large Tidal River., Harold Seelig

Theses and Dissertations

There are few published studies of larval fish assemblages from unregulated, tidal freshwater rivers. Patterns in the spatial and temporal distribution of larval fishes in the Mattaponi River were examined. Sampling took place on a weekly basis from February through August, 2006 and 2007. Larval fishes were categorized by taxa, reproductive guild, and residency guild. Group comparisons using multi-response permutation procedures (MRPP) indicated significant spatial and temporal differences in assemblage composition on multiple scales. Differences in assemblage composition were analyzed using non-metric multidimensional scaling (NMS). Interannual differences were attributable to anadromous and semi-migratory species. Seasonal differences were attributable to herrings, …

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Family Preservation In Families’ Ecological Systems: Factors That Predict Out-Of-Home Placement And Maltreatment For Service Recipients In Richmond City, Jody Hearn Apr 2010

Family Preservation In Families’ Ecological Systems: Factors That Predict Out-Of-Home Placement And Maltreatment For Service Recipients In Richmond City, Jody Hearn

Theses and Dissertations

Family preservation services are intended to prevent the out-of-home placement (into foster care or some other alternative arrangement) of children and youth in families at risk of maltreating them. An Ecological Systems perspective of these families might suggest that a family’s context (represented by the variables of poverty, agency services, family history, and individual/caretaker characteristics) must be considered as an over-arching influence in families’ risk and outcomes. The purpose of this cross-sectional secondary data analysis study was to identify layered factors that distinguish family preservation cases in Richmond, VA that experience removal or subsequent abuse or neglect from those that …

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Tied Together: A Molecular Role For Tie1 In Angiopoietin Tie2 Signaling, Tom Cm Seegar Apr 2010

Tied Together: A Molecular Role For Tie1 In Angiopoietin Tie2 Signaling, Tom Cm Seegar

Theses and Dissertations

The primary function of the vascular system is the maintenance of oxygen homeostasis for all metazoan tissue. Angiogenesis, the remodeling and maintenance of new blood vessels from an existing vessel, is primarily controlled through the endothelial specific receptor tyrosine kinase Tie2, and the orphan receptor tyrosine kinase, Tie1. Although these receptors share highly conserved, genetic and biochemical analysis has shown these receptors have distinct and essential roles in angiogenesis. Tie2 activation typically results in vessel stability and quiescences and has further been shown to interact with all four sub-types of the angiopoietin signaling factors, Ang1-4. Conversely, Tie1 is involved in …

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Commonwealth Times 2010-04-29 Apr 2010

Commonwealth Times 2010-04-29

Commonwealth Times, 1969-

No abstract provided.

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The Mechanism Of Mitochondrial Folate Transport By The Mitochondrial Folate Transporter, Scott Alan Lawrence Apr 2010

The Mechanism Of Mitochondrial Folate Transport By The Mitochondrial Folate Transporter, Scott Alan Lawrence

Theses and Dissertations

The mitochondrial folate transport protein (MFT) functions to transport folates into the mitochondrial matrix. The MFT is a member of a mitochondrial carrier family (MCF) of proteins that have a high degree of sequence and structural similarities, yet they transport vastly different substrates at high specificities. In this dissertation research, the folate-specific transport mechanism of the MFT was explored using experimental and computational techniques. MFT residues that differed from MCF consensus residues in conserved PxD/ExxK/R motifs and at a predicted substrate-binding site common to all MCF proteins were investigated. Site-directed mutagenesis of these anomalous residues in the MFT revealed that …

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Insulin-Like Growth Factor Binding Protein-3 (Igfbp-3) Plays An Essential Role In Cellular Senescence: Molecular And Clinical Implications., Amanda Garza Apr 2010

Insulin-Like Growth Factor Binding Protein-3 (Igfbp-3) Plays An Essential Role In Cellular Senescence: Molecular And Clinical Implications., Amanda Garza

Theses and Dissertations

Normal somatic cells have a limited proliferative capacity in vivo and in vitro, termed senescence and later, thought to contribute to molecular and cellular organismal aging. There are several studies that demonstrate the importance of the GH/IGF axis in longevity, aging and cellular senescence. One primary component of the IGF signaling involves IGFBP-3. It is well documented that IGFBP-3 levels are significantly increased in senescent human diploid fibroblasts however IGFBP-3 function is not known in this system. Interestingly, Werner syndrome fibroblasts, commonly used as a model of cellular aging, have upregulated IGFBP-3 levels in young and late passage cells compared …

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Duality Of A Cage, Younseal Eum Apr 2010

Duality Of A Cage, Younseal Eum

Theses and Dissertations

My thesis is about the dualistic connotation of the cage. The original intention of a cage is to create a boundary to enclose a target. However, a cage has a positive intent for protection. With this idea, I created kinetic sculpture and installation pieces referencing cages. While I understand the negative association of cages, I made them seductive through the careful consideration of lightness, fragility, and sheen. I have been exploring forms and material qualities to express the contradictory connotation of cages. Most of my work is made of wire because I have a great interest in the delicate nature …

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Expression & Purification Of Recombinant Plasmodium Falciparum Erythrocyte-Binding Ligands, Seward Joann Cofie Apr 2010

Expression & Purification Of Recombinant Plasmodium Falciparum Erythrocyte-Binding Ligands, Seward Joann Cofie

Theses and Dissertations

Plasmodium falciparum, the most virulent malarial parasite, is capable of invading all known human blood types. Erythrocyte invasion depends on specific parasite ligand and erythrocyte receptor interactions. These interactions are mediated by Region II of the P. falciparum erythrocyte binding ligands. Although invasion does not seem dependent upon a singular ligand, their individual contributions to the invasion process are yet to be explained. In this study, Region II of P. falciparum binding ligands BAEBL and JESEBL were transiently expressed as hexahistidyl recombinant proteins in COS-1 cells. Purification by column chromatography yielded 0.52 mg of BAEBL and 0.433 mg of JESEBL. …

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You're Gonna Be Ok: A System To Control The Uncontrollable, John Hendershot Apr 2010

You're Gonna Be Ok: A System To Control The Uncontrollable, John Hendershot

Theses and Dissertations

This is a written defense to accompany the MFA Thesis Exhibition You’re Gonna Be Ok, an installation encompassing video, and other sensory components. This defense provides background for the artist’s motivation to make this work, along with a theoretical framework used to construct the installation. Accompanying photos, video, and PowerPoint are also included to give reference and documentation of the installation event.

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An Efficient Implementation Of An Exponential Random Number Generator In A Field Programmable Gate Array (Fpga), Smitha Gautham Apr 2010

An Efficient Implementation Of An Exponential Random Number Generator In A Field Programmable Gate Array (Fpga), Smitha Gautham

Theses and Dissertations

Many physical, biological, ecological and behavioral events occur at times and rates that are exponentially distributed. Modeling these systems requires simulators that can accurately generate a large quantity of exponentially distributed random numbers, which is a computationally intensive task. To improve the performance of these simulators, one approach is to move portions of the computationally inefficient simulation tasks from software to custom hardware implemented in Field Programmable Gate Arrays (FPGAs). In this work, we study efficient FPGA implementations of exponentially distributed random number generators to improve simulator performance. Our approach is to generate uniformly distributed random numbers using standard techniques …

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The Middle School Transition In Private Schools: Student Perceptions, Eileen Atkinson Apr 2010

The Middle School Transition In Private Schools: Student Perceptions, Eileen Atkinson

Theses and Dissertations

Abstract THE MIDDLE SCHOOL TRANSITION IN PRIVATE SCHOOLS: STUDENT PERCEPTIONS By Eileen Irby Atkinson, Ph.D. A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University. Virginia Commonwealth University, 2010 Director: Cheryl Magill, Ph.D., Assistant Professor, Department of Educational Leadership Students transitioning into the middle school often experience difficulty adjusting to their new environment. During this transition, declines in academic motivation, academic achievement, and connectedness have been noted. Most research on this transition has taken place in public school settings. This research investigated the impact of the middle school transition in …

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Focal Adhesion Kinase, A Major Regulator Of Oligodendrocyte Morphological Maturation And Myelination, Audrey Lafrenaye Apr 2010

Focal Adhesion Kinase, A Major Regulator Of Oligodendrocyte Morphological Maturation And Myelination, Audrey Lafrenaye

Theses and Dissertations

The formation of the myelin sheath is a crucial step during development because it enables fast and efficient propagation of signals within the limited space of the mammalian central nervous system. During the process of myelination, oligodendrocytes actively interact with the extracellular matrix (ECM). These interactions are considered crucial for proper and timely completion of the myelin sheath. However, the exact regulatory circuits involved in the signaling events that occur between the ECM and oligodendrocytes are currently not fully understood. Therefore, in this dissertation we investigated the role of a known integrator of cell-ECM signaling, namely, focal adhesion kinase (FAK), …

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Exploring The Mechanism Of Alginate Acetylation In Pseudomonas Aeruginosa, Janice Paletta Apr 2010

Exploring The Mechanism Of Alginate Acetylation In Pseudomonas Aeruginosa, Janice Paletta

Theses and Dissertations

The opportunistic pathogen P. aeruginosa is the leading cause of morbidity and mortality in cystic fibrosis patients. During chronic infection of the cystic fibrosis lung, P. aeruginosa undergoes conversion to a mucoid phenotype, constitutively producing the exopolysaccharide alginate, composed of the uronic acids D-mannuronate and L-guluronate. This alginate production contributes significantly to virulence in the cystic fibrosis lung. Evidence suggests that the acetylation state of the mannuronate component of the alginate influences the ability of components of the immune system to phagocytose the organism. To garner new and relevant information regarding the mechanism of alginate acetylation in Pseudomonas aeruginosa, a …

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Patterns In Fish Community Structure In A Regulated River, Richard Davis Apr 2010

Patterns In Fish Community Structure In A Regulated River, Richard Davis

Theses and Dissertations

I examined the abundance, composition, and distribution of fish communities in the lower Roanoke River, a hydropeaking system in North Carolina. Fishes were sampled at before and after peaking events over three years; 2007 to 2009. I evaluated trends in species richness, diversity, and assemblage composition. There were no significant differences in either richness or diversity suggesting consistent trends in richness and diversity throughout the study. I used non-metric multidimensional scaling (NMDS) to create a community composition model. Fish composition was noticeably greater post-peaking and changed minimally across time and event. There were no statistically significant differences in species composition …

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A Survey Of The Usage Of Topical Anesthesia Among Dentist, Lawrence Shults Apr 2010

A Survey Of The Usage Of Topical Anesthesia Among Dentist, Lawrence Shults

Theses and Dissertations

Purpose: The purposes of this study were four-fold: 1) to determine the types and effectiveness of various topical anesthetics being used among dentists currently treating children, 2) to determine the types of procedures for which topical anesthetics are being used among children, 3) to understand the awareness and use of a relatively newer compounded topical gel Oraqix (Dentsply Caulk) among children, 4) to understand the adverse reactions to topical anesthesia that are seen among children. Methods: A cross sectional survey was designed, regarding the type, procedural use, effectiveness, and adverse reactions noted among children to various topical anesthetics. The survey …

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Mechanisms Associated With Aging And Age-Related Disease In Drosophila, Melanie Jones Apr 2010

Mechanisms Associated With Aging And Age-Related Disease In Drosophila, Melanie Jones

Theses and Dissertations

Aging is an intrinsic process that is independent of obvious disease. In contrast to normal aging, age-related diseases are conditions that typically manifest at advanced ages, are associated with explicit pathology and cause disability and premature death. We used Drosophila as a model to investigate the molecular-genetic mechanisms associated with aging and age-related disease. Age-related locomotor impairment (ARLI) is a serious condition for the elderly and greatly impacts their quality of life. Toward identifying genes and mechanisms that influence ARLI, we performed a forward genetic screen using Drosophila mutants. This screen identified a loss of function mutant in PDK1, a …

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Oral Health Status Of Children In The Child Health Investment Partnership (Chip) Program, Latrice Foster Apr 2010

Oral Health Status Of Children In The Child Health Investment Partnership (Chip) Program, Latrice Foster

Theses and Dissertations

Purpose: The purpose of this study is to describe children’s dental disease status and functional health literacy of families enrolled in the Child Health Investment Partnership program in Roanoke Valley. Methods: This was a prospective cohort study of children (n=166) enrolled in the Child Health Investment Partnership of Roanoke Valley, Virginia (CHIP). The parents of the 166 children completed the Life Skills Progression (LSP) survey at enrollment between September 2004 and September 2008 to assess their functional health literacy levels. Their LSP scores were used to determine their subsequent health care literacy (HCL), personal health literacy (PHL), and dental-child utilization …

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Seasonal Patterns Of Nutrient Retention In A Restored Tidal Freshwater Stream Of The Mid-Atlantic Coastal Plain, Joseph Wood Apr 2010

Seasonal Patterns Of Nutrient Retention In A Restored Tidal Freshwater Stream Of The Mid-Atlantic Coastal Plain, Joseph Wood

Theses and Dissertations

Nutrient retention is governed by the interplay between physical processes that control the throughput of water and materials (i.e., water residence time), and by biological processes that govern transformation and uptake (e.g., microbial denitrification). A partial breach of the dam located on Kimages Creek (VA) re-established the historical (pre-1920) connection to the James River and provided a well-defined channel to gauge tidal exchange. We quantified tidal exchange as well as non-tidal (watershed) inputs on a monthly basis to assess Nitrogen (N) retention. Water and N fluxes were dominated by tidal exchange which was typically three times greater than inputs from …

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Mineralization Potential Of Electrospun Pdo-Nha-Fibrinogen Scaffolds Intended For Cleft Palate Repair, Isaac Rodriguez Apr 2010

Mineralization Potential Of Electrospun Pdo-Nha-Fibrinogen Scaffolds Intended For Cleft Palate Repair, Isaac Rodriguez

Theses and Dissertations

The overall goal of this study was to identify mineralized scaffolds which can serve as potential alternatives to bone graft substitutes intended for cleft palate repair. The aim of this preliminary study was to evaluate the role of fibrinogen (Fg) and nano-hydroxyapatite (nHA) in enhancing mineralization potential of polydioxanone (PDO) electrospun scaffolds. Scaffolds were fabricated by blending PDO:nHA:Fg in the following weight ratios: 100:0:0, 50:25:25, 50:50:0, 50:0:50, 0:0:100 and 0:50:50. Scaffolds were immersed in different simulated body fluids for 5 and 14 days to induce mineralization. The inclusion of fibrinogen induced sheet-like mineralization while individual fiber mineralization was noticed in …

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Characterization Of Adherence, Cytotoxicity And Biofilm Formation By Gardnerella Vaginalis, Jennifer Patterson Apr 2010

Characterization Of Adherence, Cytotoxicity And Biofilm Formation By Gardnerella Vaginalis, Jennifer Patterson

Theses and Dissertations

Worldwide, bacterial vaginosis (BV) is the most common vaginal disorder in women of childbearing age. BV is of major clinical importance due to its ability to significantly affect pregnancy outcome and enhance the transmission and acquisition of HIV. BV is characterized by a dramatic shift in the vaginal microflora; in most BV cases, the predominant bacterial species is Gardnerella vaginalis. It has been demonstrated that G. vaginalis forms an adherent biofilm on the vaginal epithelium of women with BV. Furthemore, evidence suggests that the high rate of recurrence associated with BV is related to incomplete eradication of the biofilm. The …

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A Numerical Method For Estimating The Variance Of Age At Maximum Growth Rate In Growth Models, Semhar Ogbagaber Apr 2010

A Numerical Method For Estimating The Variance Of Age At Maximum Growth Rate In Growth Models, Semhar Ogbagaber

Theses and Dissertations

Most studies on maturation and body composition using the Fels Longitudinal data mention peak height velocity (PHV) as an important outcome measure. The PHV is often derived from growth models such as the triple logistic model fitted to the stature (height) data. The age at PHV is sometimes ordinalized to designate an individual as an early, average or late maturer. In theory, age at PHV is the age at which the rate of growth reaches the maximum. Theoretically, for a well behaved growth function, this could be obtained by setting the second derivative of the growth function to zero and …

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Fundamental Work Toward An Image Processing-Empowered Dental Intelligent Educational System, Grace Olsen Apr 2010

Fundamental Work Toward An Image Processing-Empowered Dental Intelligent Educational System, Grace Olsen

Theses and Dissertations

Computer-aided education in dental schools is greatly needed in order to reduce the need for human instructors to provide guidance and feedback as students practice dental procedures. A portable computer-aided educational system with advanced digital image processing capabilities would be less expensive than current computer-aided dental educational systems and would also address some of their limitations. This dissertation outlines the development of novel components that would be part of such a system. This research includes the design of a novel image processing technique, the Directed Active Shape Model algorithm, which is used to locate the tooth and drilled preparation from …

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The Effects Of Motivational Interviewing In Pregnancy On Knowledge And Retention Of Infant Oral Health Information, Andrew Zima Apr 2010

The Effects Of Motivational Interviewing In Pregnancy On Knowledge And Retention Of Infant Oral Health Information, Andrew Zima

Theses and Dissertations

THE EFFECTS OF MOTIVATIONAL INTERVIEWING IN PREGNANCY ON KNOWLEDGE AND RETENTION OF INFANT ORAL HEALTH INFORMATION By Andrew D. Zima, Jr., B.S., M.S., D.D.S. A thesis submitted in partial fulfillment of the requirements for the degree of Masters of Science in Dentistry at Virginia Commonwealth University. Virginia Commonwealth University, 2010 Major Director: Tegwyn H. Brickhouse, D.D.S., Ph.D Associate Professor, Department of Pediatric Dentistry Purpose: The purpose was to examine the effect of motivational counseling in pregnancy with readiness and acceptance of infant oral health information. Methods: The study used a prospective cohort design to examine the effect of prenatal education …

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Small Molecule Inhibitors Of Mapk And Pi3k Pathways Enhance Mda-7 Lethality In Renal Cell Carcinoma, Patrick Eulitt Apr 2010

Small Molecule Inhibitors Of Mapk And Pi3k Pathways Enhance Mda-7 Lethality In Renal Cell Carcinoma, Patrick Eulitt

Theses and Dissertations

Renal cell carcinoma accounted for an estimated 57,760 new cases and estimated 12,980 deaths in the United States in 2009. Current treatment options for systemic renal cell carcinoma yield markedly low response percentages; however, recent cytokine therapy experiments have produced promising results. A novel adenovirus, Ad.5/3-mda-7, has been synthesized to efficiently infect renal cancer cells with the mda-7 gene. This gene encodes for the cytokine MDA-7/IL-24 that has the ability to specifically target transformed cells. Assays performed with this adenovirus resulted in an increased percentage of cell death in renal cancer cells when compared to infection with Ad.5/3-cmv empty vector. …

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Differential Roles Of The Two Major Endocannabinoid Hydrolyzing Enzymes In Cannabinoid Receptor Tolerance And Somatic Withdrawal, Joel Schlosburg Apr 2010

Differential Roles Of The Two Major Endocannabinoid Hydrolyzing Enzymes In Cannabinoid Receptor Tolerance And Somatic Withdrawal, Joel Schlosburg

Theses and Dissertations

While there is currently active debate over possible therapeutic applications of marijuana and cannabis-based compounds, consistently their primary drawbacks have been the psychoactive properties, dependence, and abuse potential. Prolonged administration of ∆9-tetrahydrocannabinol (THC), the primary psychoactive constituent in marijuana, demonstrates both tolerance and physical withdrawal in both preclinical and clinical studies. Repeated THC administration also produces CB1 receptor adaptations in the form of reduced activation of receptors, along with a downregulation of membrane surface receptors, in many brain regions involved in THC-associated behaviors. The increased need for drug to maintain therapeutic effects, and a withdrawal syndrome following discontinuation of use, …

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Implication Of Gender Stereotypes For Public Policy, Sharon Smith Apr 2010

Implication Of Gender Stereotypes For Public Policy, Sharon Smith

Theses and Dissertations

Stereotypes continue to be present and impact the assessment of women’s leadership effectiveness. Using a data set of senior executives in the public sector from The Leadership Circle multi-rater assessment tool, research supports the theory that gender influences how bosses rate their direct reports on leadership effectiveness. Survey data identifying leadership characteristics in the assessment as communal or agentic substantiate role congruence theory that women are still penalized for behaving contrary to the feminine stereotype. Role congruence theory seeks to explain the barriers that prevent women from rising into leadership positions. Representative bureaucracy explains the consequence in public policy when …

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Proteasome-Dependent Entry Of Herpes Simplex Virus, Mark Delboy Apr 2010

Proteasome-Dependent Entry Of Herpes Simplex Virus, Mark Delboy

Theses and Dissertations

Herpes simplex virus entry into cells is a multistep process that engages the host cell machinery. The proteasome is a large, ATP-dependent, multisubunit protease that plays a critical role in the maintenance of cell homeostasis. A battery of assays were used to demonstrate that proteasome inhibitors blocked an early step in herpes simplex virus entry that occurred after capsid penetration into the cytosol but prior to capsid arrival at the nuclear periphery. Proteasome-dependent viral entry was not reliant on host or viral protein synthesis. MG132, a peptide aldehyde that competitively inhibits the degradative activity of the proteasome, had a reversible …

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From The Old To The New World: The Transformation Of Kongo Minkisi In African American Art, Mary Mccurnin Apr 2010

From The Old To The New World: The Transformation Of Kongo Minkisi In African American Art, Mary Mccurnin

Theses and Dissertations

Minkisi (sing. nkisi) were sacred objects that housed ancestral spirits and were used for divination, healing and social justice by the Kongo people of Central Africa. When the Kongo were brought as slaves to the New World, they contributed significantly to the development of African American artistic and spiritual culture. In the Caribbean, aspects of minkisi have been retained in the creolized spiritual beliefs of Haitian Vodou, Cuban Palo Monte Mayombe and Brazilian Candomble. In North America, evidence of Kongo influence is apparent in examples of folk art and culture, including quilts, mojo hands, Afro-Carolinian face vessels, memory jugs and …

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The Influence Of Organizational Culture On The Existence Of Systems Employed To Improve Quality Of Care In Medical Office Practices, Donna Dugan Apr 2010

The Influence Of Organizational Culture On The Existence Of Systems Employed To Improve Quality Of Care In Medical Office Practices, Donna Dugan

Theses and Dissertations

A frequently cited reason for poor quality of care in the ambulatory care setting is the lack of optimally designed systems to address care for those with preventive or chronic care needs. Organizational theory suggests that culture plays an important role in the shaping of these types of programs. The purpose of this cross-sectional study is to understand through descriptive and regression analysis of secondary data, the relationship between the existence of cultural characteristics such as collegiality, quality emphasis and autonomy, and the systems employed to improve quality of care within primary care practices. The study uses an integrated theoretical …

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Commonwealth Times 2010-04-15 Apr 2010

Commonwealth Times 2010-04-15

Commonwealth Times, 1969-

No abstract provided.

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