Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

2012

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 4501 - 4530 of 19135

Full-Text Articles in Entire DC Network

Regulation Of To Xin Synthesis By Clostridium Difficile, Charles Darkoh Aug 2012

Regulation Of To Xin Synthesis By Clostridium Difficile, Charles Darkoh

Dissertations and Theses (Open Access)

Clostridium difficile is the leading definable cause of nosocomial diarrhea worldwide due to its virulence, multi-drug resistance, spore-forming ability, and environmental persistence. The incidence of C. difficile infection (CDI) has been increasing exponentially in the last decade. Virulent strains of C. difficile produce either toxin A and/or toxin B, which are essential for the pathogenesis of this bacterium. Current methods for diagnosing CDI are mostly qualitative tests that detect the bacterium, the toxins, or the toxin genes. These methods do not differentiate virulent C. difficile strains that produce active toxins from non-virulent strains that do not produce toxins or produce …


Direct Effects Of Metformin On Pi3k And Ras Signaling In Endometrial Cancer, David A. Iglesias M.D. Aug 2012

Direct Effects Of Metformin On Pi3k And Ras Signaling In Endometrial Cancer, David A. Iglesias M.D.

Dissertations and Theses (Open Access)

Metformin has antiproliferative effects through the activation of AMPK and has gained interest as an antineoplastic agent in several cancer types, although studies in endometrial cancer (EC) are limited. The aims of this project were to evaluate pathways targeted by metformin in EC, investigate mechanisms by which metformin exerts its antiproliferative effects, and explore rational combination therapies with other targeted agents.

Three EC cell lines were used to evaluate metformin’s effect on cell proliferation, PI3K and Ras-MAPK signaling, and apoptosis. A xenograft mouse model was also used to evaluate the effects of metformin treatment on in vivo tumor growth. These …


Ikkalpha Mediated Notch1 Activation Promotes Tumorigenesis Via Foxa2 Suppression, Mo Liu Aug 2012

Ikkalpha Mediated Notch1 Activation Promotes Tumorigenesis Via Foxa2 Suppression, Mo Liu

Dissertations and Theses (Open Access)

Proinflammatory cytokine TNFa plays critical roles in promoting malignant cell proliferation, angiogenesis, and tumor metastasis in many cancers. However, the mechanism of TNFa-mediated tumor development remains unclear. Here, we show that IKKa, an important downstream kinase of TNFa, interacts with and phosphorylates FOXA2 at S107/S111, thereby suppressing FOXA2 transactivation activity and leading to decreased NUMB expression, and further activates the downstream NOTCH pathway and promotes cell proliferation and tumorigenesis. Moreover, we found that levels of IKKa, pFOXA2 (S107/ 111), and activated NOTCH1 were significantly higher in hepatocellular carcinoma tumors than in normal liver tissues and that pFOXA2 (S107/111) expression was …


Enzyme Actuated Bioresponsive Hydrogels, Andrew Wilson Aug 2012

Enzyme Actuated Bioresponsive Hydrogels, Andrew Wilson

All Theses

Bioresponsive hydrogels are emerging with technological significance in targeted drug delivery, biosensors and regenerative medicine. Conferred with the ability to respond to specific biologically derived stimuli, the design challenge is in effectively linking the conferred biospecificity with an engineered response tailored to the needs of a particular application. Moreover, the fundamental phenomena governing the response must support an appropriate dynamic range and limit of detection. The design of these systems is inherently complicated due to the high interdependency of the governing phenomena that guide the sensing, transduction, and the actuation response of hydrogels. To investigate the dynamics of these materials, …


Factors Affecting The Production Of Concentrated Blue Cheese Flavorings, Jason Raines Aug 2012

Factors Affecting The Production Of Concentrated Blue Cheese Flavorings, Jason Raines

All Theses

The effects of media type and culture selection on the aroma profile of Blue cheese flavorings produced using submerged culture fermentation were studied. Fermentations were carried out for 16 hours then compared using sensory analysis and GC/MS SPME. The differences between samples were minimal. Samples produced with adjunct media were found to have higher concentrations of methyl ketones and more &ldquo'creamy'&rdquo aroma character than samples produced from standard media. Higher levels of free fatty acids were found in standard media samples. Adjunct cultures appear to enhance the &ldquo'creamy'&rdquo character of Blue cheese flavorings.
Near-critical and supercritical carbon dioxide were used …


Continuum Limbed Robots For Locomotion, Alper Mutlu Aug 2012

Continuum Limbed Robots For Locomotion, Alper Mutlu

All Theses

This thesis focuses on continuum robots based on pneumatic muscle technology. We introduce a novel approach to use these muscles as limbs of lightweight legged robots. The flexibility of the continuum legs of these robots offers the potential to perform some duties that are not possible with classical rigid-link robots. Potential applications are as space robots in low gravity, and as cave explorer robots.
The thesis covers the fabrication process of continuum pneumatic muscles and limbs. It also provides some new experimental data on this technology. Afterwards, the designs of two different novel continuum robots - one tripod, one quadruped …


Development And Characterization Of Shellac-Hydroxypropyl Methyl Cellulose Composite Films With Acid Catalyst, Sana Asrar Aug 2012

Development And Characterization Of Shellac-Hydroxypropyl Methyl Cellulose Composite Films With Acid Catalyst, Sana Asrar

All Theses

The objective of this research was to develop a shellac-hydroproyl methyl cellulose (Sh-HPMC) composite film with enhanced water vapor barrier. Citric acid (CA) was used as an acid catalyst, to promote miscibility between HPMC and shellac. In a preliminary test, three different concentrations of CA (1000:1, 200:1, 100:1) were tested to identify the best Sh:CA ratio. Based on the Water vapor permeability properties and mechanical properties, Sh-CA (1000:1 ratio) had the most enhanced water vapor barrier and the lowest reduction in tensile strength compared to the pure HPMC film (control). In the later part of the research, the effect of …


Assessment Of Viability Of Probiotic Bacteria In Non Dairy Food Matrices Under Refrigeration Storage, Muthu Dharmasena Aug 2012

Assessment Of Viability Of Probiotic Bacteria In Non Dairy Food Matrices Under Refrigeration Storage, Muthu Dharmasena

All Theses

Functional foods serve nutrients and physiologically active components for a healthy living. In most countries, the products related to having a healthy gut dominate the functional foods market. These products are prebiotics, probiotics and synbiotics. Concerning the health benefits, various probiotics are introduced to food matrices. Though dairy is the ideal food matrix for probiotics, the trend of non-dairy probiotics is growing among consumers.
This study included two research objectives: surveying the commercial probiotic containing products for probiotic level and developing a practical home-made probiotic fermentation process. The first part of this study was mainly based on assessing viability of …


Chromosomal Patterns In Populations Of The Black Fly Simulium Fibrinflatum Twinn (Diptera: Simuliidae), Kyle Parks Aug 2012

Chromosomal Patterns In Populations Of The Black Fly Simulium Fibrinflatum Twinn (Diptera: Simuliidae), Kyle Parks

All Theses

Cryptic species are an important component of biodiversity, although most cryptic species have yet to be discovered. Cytogenetic studies of polytene chromosomes offer a unique level of resolution for detecting cryptic species in the family Simuliidae. Simulium fibrinflatum is a black fly morphospecies that is suspected to contain cryptic species because of its broad geographic range and variable pupal gill structure. Populations of Simulium fibrinflatum from the Saugahatchee River, AL; Anthony Shoals, GA; LaHave River, Nova Scotia; Westfield River, MA; Chauga River, SC; and Enoree River, SC, were sampled and cytogenetically analyzed to test for the presence of cryptic species. …


The Effect Of Food Ingredients On The Oxygen Barrier Properties Of Retort Materials, Amanda Ward Aug 2012

The Effect Of Food Ingredients On The Oxygen Barrier Properties Of Retort Materials, Amanda Ward

All Theses

An unexplored area in research is addressing how retorted food ingredients interact with retort packaging's oxygen barrier. Ten common food ingredients (whey protein isolate, soy protein isolate, bovine gelatin, fish gelatin, high molecular weight fish gelatin, water, air, oil, potato starch, and hydroxypropyl methylcellulose) were assessed to find their effect on the barrier properties of CPP, PET, and high barrier commercial retort pouches. OxySense Gen III 300 and Mocon OxTran 2/21 were used to evaluate the samples. CPP pouches were first assessed with the OxTran 2/21 and indicated that treatments affected the OTR's of the film materials. However, results from …


Fluid Uptake By The Lepidopteran Proboscis In Relation To Structure, Karena Kwauk Aug 2012

Fluid Uptake By The Lepidopteran Proboscis In Relation To Structure, Karena Kwauk

All Theses

Three species of butterflies--eastern tiger swallowtail (Papilio glaucus L.), monarch (Danaus plexippus L.), and painted lady (Vanessa cardui L.)--were used to investigate the effect that exposing multiple regions of the proboscis to fluid has on feeding rate. Although the lepidopteran proboscis historically has been considered a sealed tube with a specialized region near the tip for fluid uptake, droplets of 1% sucrose solution were shown to enter multiple locations along the proboscis. Feeding experiments were conducted comparing fluid uptake rates of butterflies with their proboscises either fully or partially submerged in 1% or 15% sucrose solutions. Only one significant relationship …


The Social Psychology Of Evil: A Look At Abu Ghraib, Kristin Richardson Aug 2012

The Social Psychology Of Evil: A Look At Abu Ghraib, Kristin Richardson

All Theses

In the spring of 2004, the military police assigned to guard the Abu Ghraib prison in Baghdad, Iraq found themselves at the center of numerous investigations regarding the abuse, torture, rape, and murder of detainees in United States custody. Their behavior was influenced and encouraged by U.S. officials, including President George W. Bush and Secretary of Defense Donald Rumsfeld. The Bush administration effectively created a reality for the military police that fostered increasingly violent and aggressive tendencies beyond what is expected or allowed in similar circumstances. Existing literature and conclusions from previous studies support the claim that social and situational …


Biomass And Lipid Production From Heterotrophic And Mixotrophic Fed-Batch Cultivations Of Microalgae Chlorella Protothecoides Using Glycerol, Shwetha Sivakaminathan Aug 2012

Biomass And Lipid Production From Heterotrophic And Mixotrophic Fed-Batch Cultivations Of Microalgae Chlorella Protothecoides Using Glycerol, Shwetha Sivakaminathan

All Theses

Chlorella protothecoides is a microalga that can grow both photo-autotrophically and/or heterotrophically under different culture and environmental conditions. In this study both the heterotrophic growth and mixotrophic growth have been conducted. The heterotrophic experiments were conducted completely in the dark while the mixotrophic experiments had the dark cycles with periodic light exposure. The aim of the study was to independently understand the effect of each mode on biomass and lipid yields.
For the heterotrophic experiments, glycerol was used as an external organic carbon source while yeast extract was used as the nitrogen source. The carbon and nitrogen source were added …


Methods For Producing Stereoscopic Imagery, Matias Volonte Aug 2012

Methods For Producing Stereoscopic Imagery, Matias Volonte

All Theses

This paper describes methodologies for creating computer graphics stereoscopic imagery. This thesis details the positive and negative aspects for producing and post-producing stereoscopic imagery using different stereoscopic tools provided by Autodesk Maya and The Foundry Nuke. Also, in order to increase efficiency and decrease production time, Python tools were developed both for Maya and Nuke. Finally, the methodology proposed in this paper is fully functional and can be adopted by any production.


From Confederate Expatriates To New South Neo-Filibusters: Major Edward A. Burke And The Americas, Michael Powers Aug 2012

From Confederate Expatriates To New South Neo-Filibusters: Major Edward A. Burke And The Americas, Michael Powers

All Theses

The traditional historiography of the American South presents the New South creed as a vision emphasizing national reconciliation based upon the advancement of Southern commerce and industry. In addition, scholars broadly define New South spokesmen as men who came to maturity after the Civil War and did not involve themselves in state or national politics. An examination of Major Edward Austin Burke, however, reveals that at least one pivotal New South booster was a Confederate veteran and leading political figure; it also suggests the presence of an international component inherent in the New South paradigm of the 1880s. It is …


Microstructural And Mechanical Characterization Of Soy-Based Polyethylene Fibers, Ozgun Ozdemir Aug 2012

Microstructural And Mechanical Characterization Of Soy-Based Polyethylene Fibers, Ozgun Ozdemir

All Theses

Bio-composite fibers have attracted increasing attention from environmentally-conscious consumers because of their low cost and biodegradability. Soy protein isolates and other purified forms have been proposed as bio-based substitutes for pure synthetic polymers for use in textiles. However, fibers from pure soy proteins do not possess adequate properties for use as textile fibers. Therefore, this research aimed to investigate composite fibers consisting of soy and polyethylene for their microstructure and mechanical properties. Changes in properties with increasing filler content and long-term properties of fibers were systematically examined.
First, the microstructure of the fibers was investigated by optical analysis. Six different …


Relating Burst Pressure To Seal Peel Strength In Pouches, William Bernal Aug 2012

Relating Burst Pressure To Seal Peel Strength In Pouches, William Bernal

All Theses

This work was aimed at studying the relationship between burst pressure and seal peel strength. Past researchers developed a force balance equation based on the analysis of a force diagram to relate burst pressure to seal strength. The theoretical formula S=P(D/2) (S=Seal Strength, P=Burst Pressure, D=Restraining Plate Gap) has been studied by past researchers with contrasting results.
The theoretical formula was tested by varying dwell time to produce seals of varying strength. Pouches were burst tested at each of these dwell times to obtain burst pressures, burst peeling times, and burst locations. Corresponding peel tests were performed with crosshead speeds …


Arsenic Affects Muscle Development And Structure In Fundulus Heteroclitus, Angela D'Amico Aug 2012

Arsenic Affects Muscle Development And Structure In Fundulus Heteroclitus, Angela D'Amico

All Theses

Arsenic is a naturally occurring metalloid that can enter rivers and ground water. Epidemiological studies have correlated arsenic exposure with adverse developmental outcomes such as low birth weight, delays in the use of musculature, and altered locomotor activity. Previously in our lab, embryonically exposed killifish (Fundulus heteroclitus) were found to have changes in muscle development. Microarray analysis showed several genes involved in muscle development and formation altered and histological analysis showed an increase in small muscle fiber size. In this study, killifish were used to help understand if changes in muscle formation and fiber density after embryonic exposure persist, are …


The Formulation Of A Bone Targeted Drug Delivery System Of Poly(Glycolic Acid)-Poly(Ethylene Glycol) Coated Hydroxyapatite Nanoparticles For The Delivery Of Statins, Erika Jelen Aug 2012

The Formulation Of A Bone Targeted Drug Delivery System Of Poly(Glycolic Acid)-Poly(Ethylene Glycol) Coated Hydroxyapatite Nanoparticles For The Delivery Of Statins, Erika Jelen

All Theses

Bone is a form of mineralized connective tissue that provides strength and rigidity to the skeleton. The two primary components within bone tissue are an organic extracellular matrix, containing type I collagen, and an inorganic mineral component composed mainly of calcium phosphate hydroxyapatite crystals. Over time the microarchitecture of bone can break down due to a variety of different factors, mainly the onset of osteoporosis in post-menopausal women, Paget's disease, and the experience of a loss of gravity during space flight. Currently there are about ten million people in the United States alone suffering from osteoporosis.
The prevention of further …


Foraging Challenges: Unsuitable Prey And Limited Information, Travis M. Hinkelman Aug 2012

Foraging Challenges: Unsuitable Prey And Limited Information, Travis M. Hinkelman

School of Biological Sciences: Dissertations, Theses, and Student Research

Food acquisition is a complicated task. The profitability of potential food items depends on numerous factors, including the spatial distribution, probability of detection and capture, and suitability of the food. Animals faced with such challenges can use relatively simple mechanisms to maximize foraging efficiency. However, mechanisms that maximize foraging efficiency under some ecological conditions (e.g., prey scarcity) may produce ostensibly suboptimal behavior under different ecological conditions (e.g., prey abundance). In the work presented here, we explore two facets of foraging: (1) consuming unsuitable prey, and (2) searching for resources with limited information about resource location. To explore the consequences of …


Annual Review Of The World Pheasant Association, 2011/2012, World Pheasant Association Aug 2012

Annual Review Of The World Pheasant Association, 2011/2012, World Pheasant Association

Galliformes Specialist Group and Affiliated Societies: Reports and Other Materials

Chairman of Trustees' report, Richard Carden

Obituary: Reinhard Kruger (1938?-June 14, 2012)

Treasurer's report for the year ended April 30, 2012, Jon Riley

Achieving our charitable objectives, Philip J. K. McGowan

Galliformes Specialist Group, Peter J. Garson and Ilse Storch

Conserving Djibouti's priority land animals, Philip J.K. McGowan

Assessing the future of species on the brink, Matt Grainger

Myanmar workshop, Philip J. K. McGowan

What is the status of peafowl in Vietnam? Tommaso Savini, Vy Nguyen, and Niti Sukumal

Highlights from the European Conservation Breeding Group, Ludo Pinceel

Pipar project


Synergistic Effects Of Nanosecond Pulsed Electric Fields Combined With Low Concentration Of Gemcitabine On Human Oral Squamous Cell Carcinoma In Vitro, Jing Wang, Jinsong Guo, Shan Wu, Hongqing Feng, Shujun Sun, Jie Pan, Jue Zhang, Stephen J. Beebe Aug 2012

Synergistic Effects Of Nanosecond Pulsed Electric Fields Combined With Low Concentration Of Gemcitabine On Human Oral Squamous Cell Carcinoma In Vitro, Jing Wang, Jinsong Guo, Shan Wu, Hongqing Feng, Shujun Sun, Jie Pan, Jue Zhang, Stephen J. Beebe

Bioelectrics Publications

Treatment of cancer often involves uses of multiple therapeutic strategies with different mechanisms of action. In this study we investigated combinations of nanosecond pulsed electric fields (nsPEF) with low concentrations of gemcitabine on human oral cancer cells. Cells (Cal-27) were treated with pulse parameters (20 pulses, 100 ns in duration, intensities of 10, 30 and 60 kV/cm) and then cultured in medium with 0.01 mu g/ml gemcitabine. Proliferation, apoptosis/necrosis, invasion and morphology of those cells were examined using MTT, flow cytometry, clonogenics, transwell migration and TEM assay. Results show that combination treatments of gemcitabine and nsPEFs exhibited significant synergistic activities …


Dissolute Pluralism: An Ethics Of Queer Thought, Kristin P. Mccartney Aug 2012

Dissolute Pluralism: An Ethics Of Queer Thought, Kristin P. Mccartney

College of Liberal Arts & Social Sciences Theses and Dissertations

Every practice has a theory, but multiracial queer social movements have centered theory in their praxis. In consciousness-raising and affinity groups, listservs and electronic forums, zines and community action research projects, participants frame the task of thought itself as collective and interactive, subject not just to evolving norms, but also to vicissitudes of duration, location, and timing, medium, ritual, and personality. I argue that the ephemeral character of these interventions is not incidental or regrettable, but designed to encourage organic participation and obstruct institutional codification. In turn, these values and tactics call academics to interrogate how they enter into this …


Oil, Politics, Society And The State In The Middle East: Enduring Authoritarianism In Iran And Saudi Arabia, Benjamin E. Martorell Aug 2012

Oil, Politics, Society And The State In The Middle East: Enduring Authoritarianism In Iran And Saudi Arabia, Benjamin E. Martorell

College of Liberal Arts & Social Sciences Theses and Dissertations

This thesis examines the relationship between oil and the persistence of authoritarianism in the Middle East. Specifically, it analyzes and critiques the rentier state theory and argues that oil is one of several other, arguably more consequential, factors (political structures, religion, history/actions of external actors, and state mechanisms and strategies) that account for the persistence of authoritarianism in the Middle East


Yeast Surface Display Of Cd154, Iaryna Masniuk Aug 2012

Yeast Surface Display Of Cd154, Iaryna Masniuk

Graduate Theses and Dissertations

The CD154 (CD40L) is a member of tumor necrosis factor (TNF) family that plays a crucial role in regulation of both cell-mediated and humoral immunity by activating antigen presenting cells (APCs). Previously, studies in the laboratory demonstrated that yeast surface display system allows the expression of biologically functional antigen, such as subunit HA, against influenza virus. Yeast surface display system seems to be an excellent system to be utilized to develop anti-influenza virus vaccine. Thus, it is of interest to study the adjuvant function of CD154 on the subunit HA vaccine against influenza virus. In this project, the CD154 encoding …


Patronage Employment: Limiting Litigation, Susan Lorde Martin Aug 2012

Patronage Employment: Limiting Litigation, Susan Lorde Martin

San Diego Law Review

First, this Article describes the development of the patronage and civil service systems with a reflection on how they work in tandem. Then, the trio of cases, Elrod v. Burns, Branti v. Finkel, and Rutan v. Republican Party of Illinois, is reviewed. How the federal circuit courts have responded to these three cases is examined both in their immediate aftermath and in decisions in more recent cases. Finally, the Article discusses some specific examples of how the current law creating First Amendment rights against negative employment decisions for patronage appointees is not working and how it should be changed.


Managing Pasture As A Crop - Darrell Emmich, Darrell Emmick Aug 2012

Managing Pasture As A Crop - Darrell Emmich, Darrell Emmick

Faculty & Staff Scholarship

No abstract provided.


Ethical Issues In Religious And Spiritual Diversity Training., Mark R. Mcminn Aug 2012

Ethical Issues In Religious And Spiritual Diversity Training., Mark R. Mcminn

Faculty Publications - Doctor of Psychology (PsyD) Program

No abstract provided.


Long-Term Survival Of Anoxia Despite Rapid Atp Decline In Embryos Of The Annual Killifish Austrofundulus Limnaeus., Jason Podrabsky, Michael Menze, Steven Hand Aug 2012

Long-Term Survival Of Anoxia Despite Rapid Atp Decline In Embryos Of The Annual Killifish Austrofundulus Limnaeus., Jason Podrabsky, Michael Menze, Steven Hand

Faculty and Staff Scholarship

Embryos of the annual killifish Austrofundulus limnaeus can survive for months in the complete absence of oxygen. Survival of anoxia is associated with entry into a state of metabolic dormancy known as diapause. However, extreme tolerance of anoxia is retained for several days of post-diapause development. Rates of heat dissipation in diapause II and 4 days post-diapause II embryos were measured under aerobic conditions and during the transition into anoxia. Phosphorylated adenylate compounds were quantified in embryos during entry into anoxia and after 12 hr of aerobic recovery. Rates of heat dissipation were not affected by exposure to anoxia in …


Socio-Economic Determinants Of Out-Of-Pocket Payments On Healthcare In Pakistan, Ashar Muhammad Malik, Syed Iqbal Azam Shah Aug 2012

Socio-Economic Determinants Of Out-Of-Pocket Payments On Healthcare In Pakistan, Ashar Muhammad Malik, Syed Iqbal Azam Shah

Community Health Sciences

BACKGROUND:

Out-of-pocket (OOP) payment on healthcare is dominant mode of financing in developing countries. In Pakistan it is 67% of total expenditure on healthcare. Analysis of determinants of OOP health expenditure is a key aspect of equity in healthcare financing. It helps to formulate an effective health policy. Evidence on OOP in Pakistan is sparse. This paper attempts to fill this research gap.

METHODS:

We estimated determinants of OOP payments on healthcare in Pakistan. We used data sets of Pakistan Household Integrated Economic Survey (HIES) and Pakistan Standard of Living Measurement (PSLM) Survey for the year 2004-05. We developed a …