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An Examination Of The Inhibitory Effects Of Antibiotic Combinations On Ribosome Biosynthesis In Staphylococcus Aureus, Justin Beach

Electronic Theses and Dissertations

Bacteremia initiated by Staphylococcus aureus infections can be a serious medical problem. Although a number of different antibiotics are used to combat staphylococcal infections, resistance has continued to develop. Combination therapy for certain infections has been used to reduce the emergence of resistance when a single agent has become ineffective. We hypothesize that the use of rifampicin and ciprofloxacin in combination with azithromycin, known for its inhibitory effects on the bacterial ribosome, can create potential synergistic effects resulting from indirect effects on ribosomal subunit synthesis.

To determine this we measured the effects of single and multiple antibiotics on cell growth …

Methylphenidate Conditioned Place Preference In Juvenile And Adolescent Male And Female Rats, Elizabeth D. Freeman

Electronic Theses and Dissertations

This investigation was an analysis of the effects of methylphenidate (MPH; trade name: Ritalin) on drug reward using the conditioned place preference (CPP) behavioral paradigm in a rodent model and underlying mechanisms of this effect. Animals were conditioned in adolescence from postnatal day (P)33-39) or P44-49 with saline, 1 or 5 mg/kg MPH. Rats administered 5 mg/kg but not 1 mg/kg MPH, resulted in a significant preference that was more robust in younger male adolescent rats. The 5 mg/kg dose of MPH also resulted in a significant decrease of the dopamine transporter in both the nucleus accumbens and striatum, revealing …

Co2 Capture On Porous Adsorbents Containing Surface Amino Groups, Odette Amana Esam

Electronic Theses and Dissertations

The potential impact of carbon dioxide as a major source of global warming has led to extensive research in order to mitigate the greenhouse effect. In this work, four adsorbents were synthesized and studied. The adsorbents were obtained by grafting and sol-gel of amino-containing molecules such as bis[3-(trimethoxysilyl)propyl]amine as monoamine and [3-(2-aminoethylamino)propyl]- trimethoxysilane as diamine on the surface of silica gel. CO2 passed through adsorbents at room temperature for its capture, then desorbed at moderate heating, and stored in the form of insoluble BaCO3. The adsorbent synthesized by sol-gel synthesis was found to be more efficient due to its high …

“Between The Dream And Reality”: Divination In The Novels Of Cormac Mccarthy, Robert A. Kottage

Electronic Theses and Dissertations

Divination is a trope Cormac McCarthy employs time and again in his work. Augury, haruspicy, cartomancy, voodoo, sortition and oneiromancy all take their places in the texts, overtly or otherwise, as well as divination by bloodshed (a practice so ubiquitous as to have no formal name). But mantic practices which aim at an understanding of the divine mind prove problematic in a universe that often appears godless—or worse.

My thesis uses divination as the starting point for a close reading of each of McCarthy’s novels. Research into Babylonian, Greek, Roman and African soothsaying practices is included, as well as the …

The Sustainability Of Agriculture In Nigeria Using Rubber As A Case Study, Owen Osahon Ogbebor

Electronic Theses and Dissertations

The study is an investigation of the sustainability of agriculture in Nigeria using Rubber as case study. Edo and Abia states were sampled for the study with 300 questionnaires administered in 10 communities among rubber farmers. The study is an investigation of the socio-demographic distribution of the rubber farmers, perception of rubber farmers, and influence of government activities. Sources of information and the data were cumulated for Nigeria as a whole. The data were analyzed using statistical analysis.

Findings indicated the distribution of rubber farmers on socio-demographic distribution, sources of funds, and the effects on agricultural sustainability in Nigeria. Farmers’ …

Effect Of The Insecticide Lambda-Cyhalothrin On Rice Spider Populations In Southern Brazil, Everton N. L. Rodrigues, Milton De S. Mendonça Jr., Leila L. Fritz, Elvis A. Heinrichs, Lídia Fiuza

Department of Entomology: Faculty Publications

The adverse effect that insecticides have on spider populations is of major concern since these predators are a component in the biological control of rice insect pest populations. This study was designed to determine the effect of the pyrethroid insecticide Lambda-cyhalothrin on spider populations in rice fields. Treatments consisted of plots treated once with the insecticide and untreated plots (control). Spiders were sampled four times per crop year over a two-year period in each of three sites in the state of Rio Grande dol Sul, Brazil. Treatments were replicated four times. Sweep net sampling was conducted to sample the araneofauna. …

Plasma Antibodies To Oral Bacteria And Risk Of Pancreatic Cancer In A Large European Prospective Cohort Study, Dominique S. Michaud, Jacques Izard, Charlotte S. Wilhelm-Benartzi, Doo-Ho You, Verena A. Grote, Anne Tjønneland, Christina C. Dahm, Kim Overvad, Mazda Jenab, Veronika Fedirko, Marie Christine Boutron-Ruault, Françoise Clavel- Chapelon, Antoine Racine, Rudolf Kaaks, Heiner Boeing, Jana Foerster, Antonia Trichopoulou, Pagona Lagiou, Dimitrios Trichopoulos, Carlotta Sacerdote, Sabina Sieri, Domenico Palli, Rosario Tumino, Salvatore Panico, Peter Siersema, Petra Hm Peeters, Eiliv Lund, Aurelio Barricarte, José-María Huerta, Esther Molina-Montes, Miren Dorronsoro, J. Ramón Quirós, Eric J. Duell, Weimin Ye, Malin Sund, Björn Lindkvist, Dorthe Johansen, Kay-Tee Khaw, Nick Wareham, Ruth C. Travis, Paolo Vineis, H. Bas Bueno-De-Mesquita, Elio Riboli

Department of Food Science and Technology: Faculty Publications

Objective: Examine the relationship between antibodies to 25 oral bacteria and pancreatic cancer risk in a prospective cohort study.

Design: We measured antibodies to oral bacteria in prediagnosis blood samples from 405 pancreatic cancer cases and 416 matched controls, nested within the European Prospective Investigation into Cancer and Nutrition study (EPIC). Analyses were conducted using conditional logistic regression and additionally adjusted for smoking status and body mass index.

Results: Individuals with high levels of antibodies against Porphyromonas gingivalis ATTC 53978, a pathogenic periodontal bacteria, had a 2-fold higher risk of pancreatic cancer than individuals lower levels of …

The Mir-17/92 Cluster: A Comprehensive Update On Its Genomics, Genetics, Functions And Increasingly Important And Numerous Roles In Health And Disease., Elena Mogilyansky, Isidore Rigoutsos

Computational Medicine Center Faculty Papers

The miR-17/92 cluster is among the best-studied microRNA clusters. Interest in the cluster and its members has been increasing steadily and the number of publications has grown exponentially since its discovery with more than 1000 articles published in 2012 alone. Originally found to be involved in tumorigenesis, research work in recent years has uncovered unexpected roles for its members in a wide variety of settings that include normal development, immune diseases, cardiovascular diseases, neurodegenerative diseases and aging. In light of its ever-increasing importance and ever-widening regulatory roles, we review here the latest body of knowledge on the cluster's involvement in …

Remote Estimation Of Nitrogen And Chlorophyll Contents In Maize At Leaf And Canopy Levels, Michael Schlemmer, Anatoly A. Gitelson, James S. Schepers, Richard B. Ferguson, Y. Peng, J. Shanahan, Donald Rundquist

Department of Agronomy and Horticulture: Faculty Publications

Leaf and canopy nitrogen (N) status relates strongly to leaf and canopy chlorophyll (Chl) content. Remote sensing is a tool that has the potential to assess N content at leaf, plant, field, regional and global scales. In this study, remote sensing techniques were applied to estimate N and Chl contents of irrigated maize (Zea mays L.) fertilized at five N rates. Leaf N and Chl contents were determined using the red-edge chlorophyll index with R2 of 0.74 and 0.94, respectively. Results showed that at the canopy level, Chl and N contents can be accurately retrieved using green and red-edge Chl …

Optimal Copper Supply Is Required For Normal Plant Iron Deficiency Responses, Brian M. Waters, Laura C. Armbrust

Department of Agronomy and Horticulture: Faculty Publications

Iron (Fe) and copper (Cu) homeostasis are tightly linked across biology. Understanding crosstalk between Fe and Cu nutrition could lead to strategies for improved growth on soils with low or excess metals, with implications for agriculture and phytoremediation. Here, we show that Cu and Fe nutrition interact to increase or decrease Fe and/or Cu accumulation in leaves and Fe uptake processes. Leaf Cu concentration increased under low Fe supply, while high Cu lowered leaf Fe concentration. Ferric reductase activity, an indicator of Fe demand, was inhibited at insufficient or high Cu supply. Surprisingly, plants grown without Fe were more susceptible …

Repeated Elevational Transitions In Hemoglobin Function During The Evolution Of Andean Hummingbirds, Joana Projecto-Garcia, Chandrasekhar Natarajan, Hideaki Moriyama, Roy E. Weber, Angela Fago, Zachary A. Cheviron, Robert Dudley, Jimmy A. Mcguire, Christopher C. Witt, Jay F. Storz

School of Biological Sciences: Faculty Publications

Animals that sustain high levels of aerobic activity under hypoxic conditions (e.g., birds that fly at high altitude) face the physiological challenge of jointly optimizing blood-O₂ affinity for O₂ loading in the pulmonary circulation and O₂ unloading in the systemic circulation. At high altitude, this challenge is especially acute for small endotherms like hummingbirds that have exceedingly high mass-specific metabolic rates. Here we report an experimental analysis of hemoglobin (Hb) function in South American hummingbirds that revealed a positive correlation between Hb-O₂ affinity and native elevation. Protein engineering experiments and ancestral- state reconstructions revealed that this …

Towards Operationalizing Complexity Leadership: How Generative, Administrative And Community-Building Leadership Practices Enact Organizational Outcomes, James K. Hazy, Mary Uhl-Bien

Department of Management: Faculty Publications

Over five years ago, The Leadership Quarterly published a special issue on complexity to advance a new way of thinking about leadership. In shifting attention away from the individual to the organizing process itself, complexity added an important focus on process and context to leadership and management research. Yet, the complexity approach creates challenges for researchers who must combine or replace individual level constructs—like those built through surveys or factor analysis—with richer theories that investigate networked meso dynamics, multilevel phenomena, emergent processes, and organizational outcomes. To address this challenge, the present analysis draws on theoretical and empirical work over the …

On Head Lice And Social Interaction In Archaic Andean Coastal Populations, Bernardo Arriaza, Vivien Standen, Karl Reinhard, Aduto Araújo, Jörg Heukelbach, Katharina Dittmar

Karl Reinhard Publications

Archaic mummies from northern Chile were examined for the presence of Pediculus humanus capitis. The excellent preservation of mummies and louse nits/eggs permitted a study of the degree of head lice infestation. We studied 63 Chinchorro mummies (ca. 5000–3000 years B.P.) from the Arica-Camarones coast. An area of 2 cm × 2 cm on each mummy’s head was systematically inspected for louse nits/eggs. Hairs with nits/eggs and lice were collected and analyzed using optic and scanning electronic microscopy. About 79% (50/63) of the mummies resulted positive for pediculosis, with an average of 2.1 nits/ eggs/cm2 per positive individual. Microscopic …

Mechanisms Of Hemolysis-Associated Platelet Activation, Christine C. Helms, M. Marvel, W. Zhao, M. Stahle, R. Vest, G. J. Kato, J. S. Lee, G. Christ, M. T. Gladwin, R. R. Hantgan, D. B. Kim-Shapiro

Physics Faculty Publications

Background

Intravascular hemolysis occurs after blood transfusion, in hemolytic anemias, and in other conditions, and is associated with hypercoagulable states. Hemolysis has been shown to potently activate platelets in vitro and in vivo, and several mechanisms have been suggested to account for this, including: (i) direct activation by hemoglobin (Hb); (ii) increase in reactive oxygen species (ROS); (iii) scavenging of nitric oxide (NO) by released Hb; and (iv) release of intraerythrocytic ADP.

Objective

To elucidate the mechanism of hemolysis-mediated platelet activation.

Methods

We used flow cytometry to detect PAC-1 binding to activated platelets for in vitro experiments, and a …

Scanned Ion Beam Therapy For Thoracic Tumors, John Gordon Eley

Dissertations and Theses (Open Access)

Although frequently cured of Hodgkin lymphoma, adolescents and young adults can develop radiation induced second cancers. These patients could potentially benefit from scanned ion radiotherapy yet likely would require motion mitigation strategies. In theory, four-dimensional (4D) optimization of ion beam fields for individual motion states of respiration can enable superior sparing of healthy tissue near moving targets, compared to other motion mitigation strategies. Furthermore, carbon-ion therapy can sometimes provide greater relative biological effectiveness (RBE) for cell sterilization in a target but nearly equivalent RBE in tissue upstream of the target, compared to proton therapy. Thus, we expected that for some …

Methylmercury Fate In The Hypersaline Environment Of The Great Salt Lake: A Critical Review Of Current Knowledge, Danielle Barandiaran

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Methylmercury (MeHg) is a highly potent neurotoxic form of the environmental pollutant Mercury (Hg). The processes that are responsible for the conversion of Hg to MeHg are known to be both biotic and abiotic in freshwater systems. Although MeHg contamination is well documented in Great Salt Lake (GSL), the conversion of Hg into MeHg is not well-understood in saline environments much less in hypersaline waters such as GSL. The GSL is a broad, shallow high altitude (1280 m above sea level) lake that is exposed to large amounts of ultraviolet radiation and evaporation, which lead to great volatilization losses of …

The Modern Language Classroom: Individuality, Technology, And Context, Eric Sims

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This portfolio is a compilation of the author’s research-supported ideas on what good language teaching looks like. The central component is the teaching philosophy, in which the author explains that respect for individuality, use of technology, and use of culture as context for learning are the three elements seen as most important for successful language learning.
The teaching philosophy is supported by artifacts about peer feedback in language learning, literacy in adult English as a Second Language learners, and autonomy in culture learning. Finally, in three annotations the author branches out from the pillars of the teaching philosophy and examines …

Evaluating The Smart Steps For Stepfamilies: Embrace The Journey Program, A Hierarchical Examination, Katie L. Reck

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over the past decade, relationship education has grown as a means of enhancing couple relations. This study examines the experiences of 2,828 ethnically diverse and low-income adults who participated in the Smart Steps for Stepfamilies: Embrace the Journey program, a 12-hour stepfamily education program. Self-report measures of relationship quality, couple commitment, and relationship instability were gathered prior to and immediately after the Smart Steps intervention as well as six weeks, six months, and one year post-program. Results suggest that stepfamily participants experienced increases in relationship quality; however, these increases reduced to near pre-program levels one year after the programs completion. …

Computer Self-Efficacy, Cognitive Actions, And Metacognitive Strategies Of High School Students While Engaged In Interactive Learning Modules, Harry Budi Santoso

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research was to investigate high school students’ computer self-efficacy, cognitive actions, and metacognitive strategies in a self-regulated learning (SRL) framework while utilizing an interactive learning module. The researcher hypothesized that computer self-efficacy is correlated positively with cognitive actions and metacognitive strategies while the students are engaged with interactive learning modules. This research used a mixed-methods approach to answer the research questions. Two research questions guided this research: (1) How is students’ computer self-efficacy related to cognitive actions and metacognitive strategies while using interactive learning modules?; and (2) How do students plan monitor their cognitive actions, and …

Will A Confederate's Initial Decline Of Assistance Influence People's Willingness To Help Others?, Israel Vela

Theses and Dissertations - UTB/UTPA

Observational study testing the effect a confederate has on social influence. The study examined whether overhearing a prior refusal to assist from a confederate had an influence on a subsequent person’s willingness to help in time of need. Similarity characteristics between model and participant were also examined to determine if they contributed to an increased likelihood of helping. Observation was held at the University of Texas-Pan American and consisted of 60 male participants. Participants were approached, and asked for assistance, in two separate conditions: Experimental (confederate) condition (n=30) and Control (non-confederate) condition (n=30). Assistance was determined by a participant’s willingness …

Constructing The Rod Bipolar Cell Signalplex Using Animal Models Of Retinal Dysfunction., Thomas Andrew Ray 1986-

Electronic Theses and Dissertations

Glutamate mediated neurotransmission from the rod photoreceptors to rod bipolar cells is critical for vision under low light levels. Disruption of this pathway results in the blinding disorder Congenital Stationary Night Blindness (CSNB), which is hallmarked by the inability to see under dim light. Mouse models of CSNB have been critical to identifying proteins required for glutamate signaling and understanding the mechanism of signaling. Currently, our understanding of rod bipolar signaling is incompletely understood because not all of the protein components of the signalplex have been identified. It was known that the glutamate receptor mGluR6 is coupled to the TRPM1 …

Territoriality And Landscape Of Aggression., Piyumika Sureshni Suriyampola

Electronic Theses and Dissertations

Behavioral adjustments in response to the presence of landmarks can exert strong effects on population dynamics of territorial species as well as the evolution of behavior and social systems. Hence, an understanding of the role of landmarks in animal contests provides a link between behavioral decision-making and population dynamics, which has been viewed as a major goal in ecology. This dissertation investigates the effects of landmarks on territory defense, focusing on how landmarks affect differences in sex roles, the landscape of aggression and fundamental territory properties. To investigate these ideas, I used three different cichlid fish species as model systems. …

A Semi-Empirical Hamiltonian For Boron, Phosphorus And Compounds Containing Boron, Phosphorus And Silicon., Paul S. Tandy

Electronic Theses and Dissertations

In this work, a 25 parameter semi-empirical Hamiltonian for boron and phosphorus is developed. The Hamiltonian contains both environment-dependent terms and electron-correlation terms with the on-site charge calculated self-consistently. One of the goals of this work is to obtain the parameterized Hamiltonian for boron and phosphorus by fitting the properties of small boron and phosphorus clusters and the bulk phases, as obtained by our method, to ab-initio calculations. The general structure of this Hamiltonian and all phenomenological functions contained within have been successful in predicting the properties of intermediate silicon clusters as well as extended structures of silicon with great …

Discursive Affordances : Police, Transfer, And The Performance Of Identity., Robert John Terry

Electronic Theses and Dissertations

This dissertation is an analysis of how the performance of identity affects the possibilities for the transfer of writing strategies. It begins with a literature review of the existing research on transfer within the field of composition and posits that an undertheorized understanding of identity may be leading to misunderstandings related to the transfer of knowledge. It then provides a framework for understanding the performance of identity developed through James Paul Gee's Discourse theory and provides a framework for understanding and identifying Discourse conflicts related to the performance of identity. After providing an overview of the research site, the Administrative …

A Microreactor Approach For Chemoselective Capture And Analysis Of Carbonyl Compounds In Air And Exhaled Breath., Mingxiao Li

Electronic Theses and Dissertations

Detection of volatile organic compounds (VOCs) at trace level (parts per billion volume (ppbv) to parts per trillion (pptv)) has become an important research area because of demanding applications in homeland security, environmental monitoring, and noninvasive diagnosis of diseases. The analysis of trace VOCs challenges existing analytical instruments because their concentrations are beyond current instrument limits of detection. In this dissertation, we have investigated an innovative microreactor that is suitable for quantitative analysis of volatile carbonyl compounds in ambient air as well as in human exhaled breath. The approach is based on microreactor chips fabricated from four inch silicon wafers. …

Predictors Of Hiv Risk Behaviors Among Older Adults : A Multilevel Analysis., Laneshia Rae' Mccord

Electronic Theses and Dissertations

Over the past thirty years, HIV has become a worldwide epidemic. Given the surge in the rate of sexually transmitted diseases including HIV, this sheds light as a new worry for sexually active older adults, raising questions about risk behaviors among this group. The issues facing older adults are three-fold in that they are 1) not identifying themselves as being at risk; 2) not identifying risk behaviors; and 3) are not largely being identified in the public realm as participating in risk behaviors. For these reasons, understanding both environmental and individual factors and their unique influences on HIV risk behaviors …

Navigating The Field : An Examination Of Rhetorical Spaces In The Journal Of Sex Research., Deanna Mcgaughey-Summers

Electronic Theses and Dissertations

In this dissertation, I adopt a praxical theory of rhetorical space to identify and examine how members of The Society for the Scientific Study of Sexuality draw on or invoke rhetorical spatiality in their research published in the Journal of Sex Research. My specific research questions were: (1) What types of rhetorical spaces do sexologists create? and, (2) What rhetorical strategies do sexologists use to create rhetorical spaces? The dissertation is divided into five chapters that present different investigations of the production of rhetorical space in The Journal of Sex Research. Chapter One introduces the theoretical and methodological foundation for …

Community Level Impacts Of Microstegium Vimineum On Arthropod Community Structure And Foodweb Dynamics In A Temperate Deciduous Forest., Judith L. Metcalf

Electronic Theses and Dissertations

Invasion by non-native primary producers are generally expected to lead to a decline in native species richness, however in some cases, these invasions can actually lead to an increase in diversity and abundance of certain groups of organisms. Arthropods are extremely sensitive to changes in the plant community, particularly herbivores, and the response of these primary consumers can influence predator populations. Microstegium vimineum is an invasive C4 grass that has developed strong populations in the understory of temperate deciduous forests along the east coast of the U.S. This work evaluates the influence that this invader may have on insect and …

Success On Their Own Terms : Youths' Perspectives On What It Means To Be Successful In Foster Care., Justin Miller

Electronic Theses and Dissertations

Foster care is a fundamental component of the child welfare system. Traditionally, foster care has been viewed as the primary mechanism for caring for children placed outside of their home, and is considered one of the central intervention strategies for child welfare practitioners. Foster care services are regularly recommended for children who are abused and neglected. In 2011, there were an estimated 401,000 youths in foster care and approximately 646,000 youth were served by the foster care system. Yet, despite the importance of foster care to child welfare, social work literature in general, and child welfare literature specifically, is devoid …

Repair Of The Airway Epithelium After Chlorine-Induced Injury., Sadiatu Musah

Electronic Theses and Dissertations

Chlorine is a widely used toxic chemical that is considered a chemical threat agent. Chlorine inhalation injures airway epithelium, and efficient epithelial repair is necessary to restore normal lung structure and function. Regeneration of injured tissues typically proceeds through the proliferation and differentiation of stem or progenitor cells. Knowledge of underlying mechanisms that regulate these processes during airway epithelial repair is lacking. This dissertation characterizes respiratory epithelial repair after chlorine injury to investigate potential signaling pathways that could be manipulated to regulate stem/progenitor cells in airway repair. Repair of the pseudostratified tracheal epithelium after chlorine-induced injury was characterized in C57BL/6 …