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2019

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Synthesis And Bioevaluation Of Methionine Depletion Agents, Houssine Ikhlef Jan 2019

Synthesis And Bioevaluation Of Methionine Depletion Agents, Houssine Ikhlef

Electronic Theses and Dissertations

The native polyamines (putrescine, spermidine, and spermine) are low molecular weight amines that exist as polycations at physiological pH. These polycations interact with DNA, RNA, and influence many cellular processes. Intracellular polyamine levels are maintained via a balance of polyamine biosynthesis, catabolism, and transport. Ornithine, an amino acid obtained from L-arginine, is decarboxylated by ornithine decarboxylase (ODC) to form putrescine. The biosynthesis of the higher polyamines, spermidine and spermine, requires the addition of an amino-propyl group donated by decarboxylated S-adenosylmethionine (dc-SAM), which itself is derived from the amino acid L-methionine (Met). Tumor cells are heavily reliant on methionine because it …

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Tumor-Targeted Conjugated Polymer Nanoparticles With Encapsulated Iron And Its Biomedical Application For In Vitro Killing Of Melanoma Cell Lines Through Ferroptosis Assisted Chemodynamic Therapy (Cdt), Khalaf Jasim Jan 2019

Tumor-Targeted Conjugated Polymer Nanoparticles With Encapsulated Iron And Its Biomedical Application For In Vitro Killing Of Melanoma Cell Lines Through Ferroptosis Assisted Chemodynamic Therapy (Cdt), Khalaf Jasim

Electronic Theses and Dissertations

Melanoma represents one of the most aggressive and lethal forms of skin cancer, with annually rising incidences throughout the world. Although chemotherapy modalities remain the mainstay of treatment, the therapeutic potential of chemotherapy typically is hampered by multidrug resistance (MDR) and nonspecific drug distribution that causes side-effects. To surmount such limitations, novel nanoformulations of low band-gap poly ({4,8-bis [(2-ethylhexyl) oxy] benzo [1,2-b:4,5-b?] dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl) carbonyl] thieno [3,4-b] thiophenediyl}) (PTB7) and poly [2,1,3-benzothiadiazole- 4,7- diyl [4,4-bis (2-ethylhexyl)- 4H-cyclopenta [2,1-b:3,4-b'] dithiophene-2,6-diyl]] (PCPDTBT) were fabricated by a reprecipitation method. These conjugated polymer nanoparticles were functionalized with the polypeptide endothelin-3 (EDN3-CPNPs) to target melanoma. The …

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Structure Of Reflectin Protein Probed By Solid-State Nuclear Magnetic Resonance, Tommy Boykin Jan 2019

Structure Of Reflectin Protein Probed By Solid-State Nuclear Magnetic Resonance, Tommy Boykin

Electronic Theses and Dissertations

An unusual protein found in squids, termed reflectin, possesses the unique ability for optical reflectivity and proton conductivity. Reflectin has the potential to become optically and electronically tunable, however, the molecular structure of reflectin has yet to be determined. Previous literature has considered using reflectin proteins as diffraction gratings, protonic transistors, and substrates for neural stem cell growth. Applying recombinant protein techniques, we purified the reflectin 4Ax4 protein. We determined the leucine, tryptophan, and threonine amino acids are in an ordered state by solid-state nuclear magnetic resonance (NMR). Knowing these ordered amino acids is possibly the key to understanding reflectin's …

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Kindergarten Is Not Child's Play: An Exploration Of Pedagogical Approaches Related To Learning In A Play-Based And A Contemporary Classroom At A Title I Elementary School, Karyn Allee-Herndon Jan 2019

Kindergarten Is Not Child's Play: An Exploration Of Pedagogical Approaches Related To Learning In A Play-Based And A Contemporary Classroom At A Title I Elementary School, Karyn Allee-Herndon

Electronic Theses and Dissertations

This dissertation is divided into three separate, related, naturalistic, quasi-experimental research studies, all using data from two kindergarten classes at Gator Elementary, a public Title I elementary school in Sunshine District in Central Florida. Each of these studies tested hypotheses that kindergarten children, especially those from low socioeconomic backgrounds, will show greater gains in receptive vocabulary, executive function, and academic achievement when purposeful play is used as a pedagogical approach than similar children in typical, contemporary kindergarten classrooms. The first study explored the effects of play-based and contemporary pedagogical approaches on students' receptive vocabulary using the PPVT-4, the second explored …

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Modeling Disease Impact Of Vibrio-Phage Interactions, Christopher Botelho Jan 2019

Modeling Disease Impact Of Vibrio-Phage Interactions, Christopher Botelho

Electronic Theses and Dissertations

Since the work of John Snow, scientists and medical professionals have understood that individuals develop cholera by means of consuming contaminated water. Despite the knowledge of cholera's route of infection, many countries have experienced and still experience endemic cholera. Cholera is caused by the Vibrio cholerae (V. cholerae) bacterium and presents with acute diarrhea and vomiting. If untreated, infected individuals may die due to dehydration. Cholera is a disease that most commonly affects countries with poor infrastructure and water sanitation. Despite efforts to control cholera in such countries, the disease persists. One such example is Haiti which has been experiencing …

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Hurricane Maria: A Qualitative Study Of Recently Displaced Students To The State Of Florida, Esmeralda Cabrera Jan 2019

Hurricane Maria: A Qualitative Study Of Recently Displaced Students To The State Of Florida, Esmeralda Cabrera

Electronic Theses and Dissertations

Over the past ten years Puerto Rico has been experiencing a severe economic crisis that was worsened when Hurricane Maria made landfall on September 20, 2017. Maria hit Puerto Rico as a category 4 storm, devastating the whole island and its 3.4 million residents. Many students were left with minimal educational choices after Hurricane Maria hit Puerto Rico. Research on Latino/a students shows that they are met with unique experiences and challenges as they pursue higher education. The current study uses qualitative data to investigate what are the unique challenges and needs of displaced students from Puerto Rico? and what …

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Hybrid Integration Of Second- And Third-Order Highly Nonlinear Waveguides On Silicon Substrates, Guillermo Fernando Camacho Gonzalez Jan 2019

Hybrid Integration Of Second- And Third-Order Highly Nonlinear Waveguides On Silicon Substrates, Guillermo Fernando Camacho Gonzalez

Electronic Theses and Dissertations

In order to extend the capabilities and applications of silicon photonics, other materials and compatible technologies have been developed and integrated on silicon substrates. A particular class of integrable materials are those with high second- and third-order nonlinear optical properties. This work presents contributions made to nonlinear integrated photonics on silicon substrates, including chalcogenide waveguides for over an octave supercontinuum generation, and rib-loaded thin-film lithium niobate waveguides for highly efficient second-harmonic generation. Through the pursuit of hybrid integration of the two types of waveguides for applications such as on-chip self-referenced optical frequency combs, we have experimentally demonstrated fabrication integrability of …

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Semi-Analytical Solutions Of Non-Linear Differential Equations Arising In Science And Engineering, Mangalagama Dewasurendra Jan 2019

Semi-Analytical Solutions Of Non-Linear Differential Equations Arising In Science And Engineering, Mangalagama Dewasurendra

Electronic Theses and Dissertations

Systems of coupled non-linear differential equations arise in science and engineering are inherently nonlinear and difficult to find exact solutions. However, in the late nineties, Liao introduced Optimal Homotopy Analysis Method (OHAM), and it allows us to construct accurate approximations to the systems of coupled nonlinear differential equations. The drawback of OHAM is, we must first choose the proper auxiliary linear operator and then solve the linear higher-order deformation equation by spending lots of CPU time. However, in the latest innovation of Liao's "Method of Directly Defining inverse Mapping (MDDiM)" which he introduced to solve a single nonlinear ordinary differential …

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Preservice Teachers And Perceived Stress: A Comparative Study, Kelsey Evans Jan 2019

Preservice Teachers And Perceived Stress: A Comparative Study, Kelsey Evans

Electronic Theses and Dissertations

Teachers are being pushed to the brink of burnout and leaving the profession, placing teachers' health and wellness in jeopardy (Daniels & Strauss, 2009; Maslach & Leiter, 2008; Stephenson, 2012; Vladut & Kallay, 2010; Wilkerson, 2009). Yet, it has become increasingly clear teacher stress may start prior to entering the profession (Brown & Ryan, 2003, Darling-Hammond, 2006). The researcher used a non-experimental design to evaluate the perceived stress among pre-service teachers enrolled in internship, and if the coping style of mindfulness had any correlation on self-reported stress levels. The quantitative study surveyed 332 student interns using the Perceived Stress Survey …

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Mathematical Investigation Of The Spatial Spread Of An Infectious Disease In A Heterogeneous Environment, Arielle Gaudiello Jan 2019

Mathematical Investigation Of The Spatial Spread Of An Infectious Disease In A Heterogeneous Environment, Arielle Gaudiello

Electronic Theses and Dissertations

Outbreaks of infectious diseases can devastate a population. Researchers thus study the spread of an infection in a habitat to learn methods of control. In mathematical epidemiology, disease transmission is often assumed to adhere to the law of mass action, yet there are numerous other incidence terms existing in the literature. With recent global outbreaks and epidemics, spatial heterogeneity has been at the forefront of these epidemiological models. We formulate and analyze a model for humans in a homogeneous population with a nonlinear incidence function and demographics of birth and death. We allow for the combination of host immunity after …

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An Exploration Of The Relationship Between Work Climate, The Utilization Of Support Resources, And Compassion Fatigue Level In Child Protective Investigators, Shannon Holliker Jan 2019

An Exploration Of The Relationship Between Work Climate, The Utilization Of Support Resources, And Compassion Fatigue Level In Child Protective Investigators, Shannon Holliker

Electronic Theses and Dissertations

The impact of child maltreatment is far reaching, affecting the abused child, the family system, and the professionals tasked with providing support during the moments of crisis. As child protective investigators (CPIs) provide care and support to others, they are at high risk of experiencing secondary traumatic stress and/or burnout, both aspects of compassion fatigue. Researchers suggest that work climate, utilization of resources, and worker characteristics can impact CPI compassion-fatigue level. Drawing on extant literature, this study examined three research questions and seven hypotheses aiming to explore the relationship between work climate, resource utilization, CPI characteristics, and CPI compassion-fatigue level. …

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Atp Induced Molecular Disassembly Of Cytolethal Distending Toxin's B/C Heterodimer, George Huhn Jan 2019

Atp Induced Molecular Disassembly Of Cytolethal Distending Toxin's B/C Heterodimer, George Huhn

Electronic Theses and Dissertations

Cytolethal distending toxin (CDT) is a virulence factor produced by many Gram-negative bacteria, including Haemophilus ducreyi. This fastidious pathogen is the causative agent of genital cancroid. CDT is a heterotrimeric toxin with an AB2 structure consisting of a cell-binding "B" domain (CdtA + CdtC) and a catalytic "A" domain (CdtB) that has DNase activity. This toxin assembles in the bacterial periplasm that lacks ATP and is secreted into the extracellular environment. After cell binding, CDT is internalized by endocytosis and travels through the endosomes and Golgi before arriving in the endoplasmic reticulum (ER). CdtA is lost from the holotoxin before …

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It Takes Two To Tango: The Toxin-Chaperone Relationship, Alisha Kellner Jan 2019

It Takes Two To Tango: The Toxin-Chaperone Relationship, Alisha Kellner

Electronic Theses and Dissertations

Cholera toxin (CT) enters the cell via receptor-mediated endocytosis and travels in a retrograde fashion to the endoplasmic reticulum (ER). The catalytic A1 subunit (CTA1) is then displaced from the rest of the holotoxin, unfolds, and is exported to the cytosol where it regains an active conformation for the ADP-ribosylation of its G-protein target. We have shown that the cytosolic chaperones Hsp90 and Hsc70 are required for CTA1 translocation to the cytosol. We have also shown that both are able to independently bind and refold CTA1. Using libraries of CTA1-derived peptides, we have identified a single Hsc70 binding site, YYIYVI …

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Science Occupational Images And Aspirations Of African American/ Black Elementary Students, Saron Lamothe Jan 2019

Science Occupational Images And Aspirations Of African American/ Black Elementary Students, Saron Lamothe

Electronic Theses and Dissertations

Within the United States, more than a million jobs in science and engineering (S&E) are projected over the next few years; yet, the Nation lacks the workforce to meet these demands. Despite the need for a more diverse, qualified workforce, African Americans/Blacks remain disproportionately underrepresented in science occupations, science degree attainment, and in science postsecondary majors. The lack of science participation is reflective of how minority secondary students view science and science occupations as many consider the pursuit of a science career as unfavorable. Moreover, minority secondary students, who do choose to pursue science occupations, seem to possess inaccurate (or …

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Ultrasound Measured Flexor Muscle Thickness In The Forearms Of Rock Climbers, Michael Marsala Jan 2019

Ultrasound Measured Flexor Muscle Thickness In The Forearms Of Rock Climbers, Michael Marsala

Electronic Theses and Dissertations

PURPOSE: To examine differences in the forearms of rock climbers using ultrasound to measure the muscle thickness of the finger flexors. METHODS: A total of 33 participants were recruited, 22 climbers (22.23 years; 68% male) and 11 controls (21.8; 55% male). Climbers provided self-reported ratings of their climbing ability, skill level, and preferred mode of climbing (e.g. sport climbing vs. bouldering). Anthropometric measures, including body fat percentage, were measured in all participants. Ultrasound measurements were taken with the participant lying on their back on a padded table with their dominant hand supinated. Muscle thickness measurements were taken at the forearm …

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If A Virtual Tree Falls In A Simulated Forest, Is The Sound Restorative? An Examination Of The Role Of Level Of Immersion In The Restorative Capacity Of Virtual Nature Environments, Jessica Michaelis Jan 2019

If A Virtual Tree Falls In A Simulated Forest, Is The Sound Restorative? An Examination Of The Role Of Level Of Immersion In The Restorative Capacity Of Virtual Nature Environments, Jessica Michaelis

Electronic Theses and Dissertations

Stress and cognitive fatigue have become a pervasive problem, especially in Western society. Stress and cognitive fatigue can have deleterious effects not only on performance, but also on one's physical and mental health. This dissertation presents a study in which the aim is to investigate the effects of virtual nature on stress reduction and cognitive restoration. Specifically, this study assessed the effects of Immersion (Non-immersive, Semi-immersive, Fully-immersive) and Exploration (Passive vs Active) on stress reduction and cognitive restoration. Additionally, restoration from the most effective virtual nature environment was compared to that of taking an active coloring break. Eighty-three university students …

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Protective Behavioral Strategies And Alcohol-Related Sex Among College Students, Roselyn Peterson Jan 2019

Protective Behavioral Strategies And Alcohol-Related Sex Among College Students, Roselyn Peterson

Electronic Theses and Dissertations

Adverse sexual outcomes (e.g., sexual regret, sexual risk, and sexual assault) are a common experience among college students. In particular, regretted sex is reported by a third of college students and may result in psychological harm. Previous literature has found that alcohol is involved in approximately one third of regretted sex experienced by college students. A gap exists in the literature identifying who is more susceptible to experiencing a regretted sexual experience. Previous research has shown that students who implement protective behavioral strategies (PBS) while drinking are able to reduce alcohol-related negative consequences, including regretted sexual experiences. Three sub-types of …

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The Life Experiences Of Women With An Intellectual Disability Who Were Sexually Assaulted, Jillian Schreffler Jan 2019

The Life Experiences Of Women With An Intellectual Disability Who Were Sexually Assaulted, Jillian Schreffler

Electronic Theses and Dissertations

The views of those with an intellectual disability (ID) on sexuality is not a topic many are willing to broach. Many challenges exist for those identified with ID when it comes to sexual education, including a lack of appropriate curricula; a lack of trained school personnel; the inability of school, state, and national stakeholders to agree on policy or curriculum content; and the generalizability of the content. These challenges are heightened by an increase in sexual assault of women with ID. To improve sexual assault prevention skills, the researcher conducted a phenomenological study to identify the current status of sexual …

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Electing Or Appointing School District Superintendents In The State Of Florida: A Comparison Of Characteristics And Performance Of Districts Led By Elected Superintendents Versus Districts Led By Appointed Superintendents, Timothy Smith Jan 2019

Electing Or Appointing School District Superintendents In The State Of Florida: A Comparison Of Characteristics And Performance Of Districts Led By Elected Superintendents Versus Districts Led By Appointed Superintendents, Timothy Smith

Electronic Theses and Dissertations

Florida and Alabama are the only two states in the United States of America with school districts led by either elected superintendents or appointed superintendents. The other 48 states only have appointed superintendent-led school districts. The current study was conducted to examine the impact of the superintendent governance structure on student learning by analyzing differences in student achievement between Florida school districts led by elected superintendents and Florida school districts led by appointed superintendents. The conceptual framework of the study was the tension between democratic localism and professionalism. Dynamics associated with the conceptual framework are relevant to the current debate. …

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Biochemical Characterization Of Rv2633c From Mycobacterium Tuberculosis And The Effects Of Mutagenesis On Iron Binding, Kyle Strickland Jan 2019

Biochemical Characterization Of Rv2633c From Mycobacterium Tuberculosis And The Effects Of Mutagenesis On Iron Binding, Kyle Strickland

Electronic Theses and Dissertations

Mycobacterium tuberculosis (Mtb) is a pathogenic bacterium that is the causative agent of the disease Tuberculosis (TB). TB kills an estimated 1.8 million people annually and roughly one third of the world's population carries Mtb in a dormant state. Drug resistant Mtb strains are on the rise, thus a new method of combating this disease is paramount. Mtb survival inside of macrophages requires overcoming various stressors such as; iron restriction, reactive oxygen species, and hypoxic conditions. Mtb employs the use of catalases, nitric oxide reductase, superoxide dismutase, and siderophores to aid in survival. These functions have also been found in …

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Stress, Coping, And Quality Of Life Among Parental Caregivers Of Children With Autism Spectrum Disorder, Dawn Turnage Jan 2019

Stress, Coping, And Quality Of Life Among Parental Caregivers Of Children With Autism Spectrum Disorder, Dawn Turnage

Electronic Theses and Dissertations

Purpose: Parental caregivers of children with Autism Spectrum Disorder (ASD) are exposed to stressors associated with the daily care of raising a child with a developmental disability, which may negatively impact parental quality of life (QOL). The specific aim of this study was to examine the relationships between demographic factors, stress, and coping among parental caregivers of children with ASD to determine whether predictors of QOL exist. Methodology: This study was descriptive, and an electronic survey was distributed to Florida parents of children, age 3-21 years old, diagnosed with ASD. The survey measured parent reported demographic factors, severity of the …

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Magnesium-Based Treatment For The Degradation Of Octachlorodibenzofuran And Trinitrotoluene, Amal Mogharbel Jan 2019

Magnesium-Based Treatment For The Degradation Of Octachlorodibenzofuran And Trinitrotoluene, Amal Mogharbel

Electronic Theses and Dissertations

The aim of the present research is to investigate the efficacy of using ball-milled zero-valent magnesium (ZVMg) with and without activated carbon (AC) for the dechlorination of polychlorinated dibenzofurans. Three different solvent systems are presented here which are ethanol, ethanol/ethyl lactate (90:10), and 2-butoxyethanol. These solvents in combination with ZVMg with and without activated carbon were tested towards the degradation of octachlorodibenzofuran (OCDF, the most highly chlorinated PCDF congener). All the tested systems were very powerful and reductively dechlorinated OCDF to less chlorinated congeners. However, the system of ball-milled ZVMg and ethanol was the only system which converted OCDF and …

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Comparative Analysis Of Zebrafish And Planarian Model Systems For Developmental Neurotoxicity Screens Using An 87-Compound Library, D. Hagstrom, L. Truong, S. Zhang, R. Tanguay, Eva-Maria S. Collins Jan 2019

Comparative Analysis Of Zebrafish And Planarian Model Systems For Developmental Neurotoxicity Screens Using An 87-Compound Library, D. Hagstrom, L. Truong, S. Zhang, R. Tanguay, Eva-Maria S. Collins

Biology Faculty Works

There is a clear need to establish and validate new methodologies to more quickly and efficiently screen chemicals for potential toxic effects, particularly on development. The emergence of alternative animal systems for rapid toxicology screens presents valuable opportunities to evaluate how systems complement each other. In this article, we compare a chemical library of 87-compounds in two such systems, developing zebrafish and freshwater planarians, by screening for developmental neurotoxic effects. We show that the systems’ toxicological profiles are complementary to each other, with zebrafish yielding more detailed morphological endpoints and planarians more behavioral endpoints. Overall, zebrafish was more sensitive to …

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Understories: A Common Ground For Art And Science, Scott F. Gilbert, S. R. Gilbert Jan 2019

Understories: A Common Ground For Art And Science, Scott F. Gilbert, S. R. Gilbert

Biology Faculty Works

No abstract provided.

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Extending The Morpheme Order Studies: Acquisition Of Modal And Non-Modal Verbal Morphemes By Esl Learners, Amal Alshehry Jan 2019

Extending The Morpheme Order Studies: Acquisition Of Modal And Non-Modal Verbal Morphemes By Esl Learners, Amal Alshehry

All Master's Theses

The morpheme order studies have long prevailed in the field of second language acquisition. However, these studies are often undermined by their extent and focus on a limited number of morphemes. Thus, the present study extends the scope of morphemes to include modal verbs within other verbal morphemes and studies the order of their acquisition. Discourse Completion Tests (DCTs) were used to examine a total of twenty-seven ESL learners from a wide range of L1 backgrounds: Japanese, Arabic, Chinese, Thai, Spanish, Turkish, Urdu, and Vietnamese. The study reveals a universal pattern in ESL learners’ acquisition of English verb morphology. …

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Sea Star Wasting Disease In Pisaster Ochraceus On The Washington Coast And In Puget Sound, Caitlin Wilkes Jan 2019

Sea Star Wasting Disease In Pisaster Ochraceus On The Washington Coast And In Puget Sound, Caitlin Wilkes

All Master's Theses

Pisaster ochraceus is a common west coast sea star whose predation of Mytilus californianus (the California mussel) increases the biodiversity of its intertidal community. Sea star wasting disease is an illness that causes sea star tissues to become necrotic until the creature wastes away and dies. In 2013, a coast wide outbreak of sea star wasting disease caused a mass mortality event in P. ochraceus. The goals of this study were to try to identify some of the possible causes for the outbreak, as well as analyze the impact that sea star wasting disease prevalence has on biodiversity. In this …

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The Chemical Analysis And Biological Activities Of The Secondary Metabolites From Dalea Mollis And Dalea Albiflora, Nicholas Peter Hansen Jan 2019

The Chemical Analysis And Biological Activities Of The Secondary Metabolites From Dalea Mollis And Dalea Albiflora, Nicholas Peter Hansen

All Master's Theses

Multidrug resistance has increased since the introduction of drugs used to prevent growth and kill microorganisms in a host. This has caused a worldwide search to discover new drugs effective against microorganisms. Mechanisms of drug resistance include, but are not limited to, the production of biofilms and efflux pumps. Efflux pumps prevent antimicrobial drugs from reaching their biological target, so the coordinated use of efflux pump inhibitors and antimicrobial drugs has been identified as a potential treatment for multidrug-resistant microorganisms. The secondary metabolites of Dalea mollis and Dalea albiflora were tested against multidrug-resistant (MDR) and engineered strains of the fungi …

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Blood, Water And Mars: Soviet Science And The Alchemy For A New Man, Sophie Y. Andarovna Jan 2019

Blood, Water And Mars: Soviet Science And The Alchemy For A New Man, Sophie Y. Andarovna

All Master's Theses

The themes of blood, water and Mars in Soviet science and technology show the strong utopian and even religious foundations of Soviet society, which invariably centered around forging a new environment and, in so doing, a new variety of human to inhabit it. In the minds and experiments of some of the radical men behind Russia’s Revolution, blood was to create a more advanced, biologically “equal” humanity capable of potential immortality, while water was harnessed with the millenarian aim of transforming the Soviet Union’s vast landscape into fields of bountiful fertility, as well as cities of efficient industry. Mars represents …

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Estimating The Economic Value Of Rock Climbing In Smith Rock: An Individual Travel Cost Approach, Cassandra Koefod Jan 2019

Estimating The Economic Value Of Rock Climbing In Smith Rock: An Individual Travel Cost Approach, Cassandra Koefod

All Master's Theses

In this study I estimate the economic value of rock climbing in Smith Rock State Park, Oregon. This area has seen an increase in recreational visits over the years, especially in rock climbing, necessitating economic valuation of the site in order to assist park managers in optimal management of this resource. Given regular conflicts over use of rock climbing areas by a variety of stakeholders (recreational users, habitats, cultural uses, etc.) this study will help in understanding how benefits of recreation is affected when policies limit access to such areas. I collect original survey data on travel to Smith Rock …

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Cold Tolerance, Temperature Mediated Discontinuous Gas Exchange, And Emergence Of The Blue Orchard Mason Bee (Osmia Lignaria), Logan Kral Jan 2019

Cold Tolerance, Temperature Mediated Discontinuous Gas Exchange, And Emergence Of The Blue Orchard Mason Bee (Osmia Lignaria), Logan Kral

All Master's Theses

The relationship between low temperatures, emergence and supercooling point of Osmia lignaria were the subject of this study. One hundred sixty-eight bees were subjected to 5 pre-wintering temperature treatments (two constant temperature controls - 22oC, 14oC, one of which with and one without a 12h photoperiod, and three 12h:12h thermoperiod treatments – 14:10oC, 14:5oC, and 14:0oC) and were then evaluated in terms of emergence time and post-emergence vigor. An additional 70 bees were tested for metabolic rate and discontinuous gas exchange in response to test temperature conditions. An additional sample …

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