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Isotropic And Anisotropic Metallic And Bimetallic Nanoparticles And Their Potential Applications In Biology, Minghong Liu

Dissertations

The development of synthetic procedures that produce nanoscale materials with controlled morphology is a significant area of investigation in nanotechnology. We have developed new synthetic procedures for fabrication of isotropic and/or anisotropic nanomaterials composed of palladium, ruthenium, nickel and alloys of palladium-ruthenium. The nanomaterials were fully characterized and were found to display unique size dependent properties. The electrochemical properties of isotropic palladium, ruthenium and palladium-ruthenium nanoparticles were investigated and the results showed that the particles were capable of charge storage and charge transfer on demand. Anisotropic palladium, ruthenium and palladium ruthenium nanoparticles were also fabricated and fully characterized. The nanoparticles …

Temporal And Spatial Assessment Of Evaporation, Transpiration, And Soil Moisture Redistribution, Brian M. Bird

UNLV Theses, Dissertations, Professional Papers, and Capstones

At a native stand of creosote bush (Larrea tridentata) in North Las Vegas, a rainfall simulation study was conducted over a 12 month period from October 2005 to October 2006. Simulated rainfall occurred during the winter, spring, summer, and fall periods. Rainfall simulation systems were positioned on each of 12 plots, each containing a single creosote bush. Simulated rainfall events occurred at night with multiple short pulses designed to maximize infiltration while minimizing ponding. Yearly simulated rainfall amounts were set at 0, 15, 30 and 60 cm (replicated three times) and were approximately 0, 1.5, 3.0 and 6.0 times the …

The Larval Salivary Gland Of Drosophila Melangogaster: A Model System For Temporal And Spatial Steroid Hormone Regulation, Benjamin Constantino

UNLV Theses, Dissertations, Professional Papers, and Capstones

Drosophila melanogaster provides an ideal model organism to test genetic and molecular biological mechanisms within the context of a living animal. For over one hundred years Drosophila continues to produce a boundless extent of informative and important scientific data providing crucial insight into development, disease progression and genetic interactions. A century as a model organism allowed for the development of an abundance of unique genetic and molecular tools allowing researchers to tease apart cellular mechanisms with very little limitation. From the whole adult body to tissue function to molecular networks, if a biological question arises it most likely can be …

Pre-Service Elementary Science Teaching Self-Efficacy And Teaching Practices: A Mixed-Methods, Dual-Phase, Embedded Case Study, Cheryl Ramirez Sangueza

UNLV Theses, Dissertations, Professional Papers, and Capstones

This mixed-method, dual-phase, embedded-case study employed the Social Cognitive Theory and the construct of self-efficacy to examine the contributors to science teaching self-efficacy and science teaching practices across different levels of efficacy in six pre-service elementary teachers during their science methods course and student teaching experiences. Data sources included the Science Teaching Efficacy Belief Instrument (STEBI-B) for pre-service teachers, questionnaires, journals, reflections, student teaching lesson observations, and lesson debriefing notes. Results from the STEBI-B show that all participants measured an increase in efficacy throughout the study. The ANOVA analysis of the STEBI-B revealed a statistically significant increase in level of …

Initial Development Of A Healthy Living Curriculum Within Family Behavior Therapy For Substance Abuse, Holly B. Lapota

UNLV Theses, Dissertations, Professional Papers, and Capstones

A mother referred for child maltreatment and substance abuse treatment after her son tested positive for methamphetamines at birth participated in an in-home Family Behavior Therapy-Healthy Lifestyle intervention to eliminate substance use, improve parenting behaviors, lose weight, and develop better exercise habits. Twenty sessions were completed in 6 months that targeted familial communication, self-control, goal setting with contingency management, job getting skills, and stimulus control techniques. Upon termination from treatment, the participant’s self-report and urine testing was consistent with substance cessation, and she evidenced substantial improvements in her level of stress, family communication and relationships, and child maltreatment potential. She …

Cascading Simulation: A Critical Perspective On Barack Obama‘S Foreign Policy During The 2008 Presidential Election, Ian P. Beier

UNLV Theses, Dissertations, Professional Papers, and Capstones

Entering the 2008 presidential election, Barack Obama had little to no foreign policy experience. On face, this would seem to make Obama an unlikely choice for President. Yet, he was able to defeat Hilary Clinton and John McCain, the two candidates with significant foreign policy experience. My thesis examines Barack Obama's speech "A World That Stands as One" as a case study for understanding how simulation operates in the context of presidential campaigns. Using Robert Entman's theory of "cascading activation," I develop a theory of "cascading simulation," arguing that image construction descends downward from the president through the media. In …

Transcriptional Regulation Of The Shigella Flexneri Icsp Promoter: Silencing And Anti-Silencing By H-Ns And Virb, Dustin Harrison

UNLV Theses, Dissertations, Professional Papers, and Capstones

Shigella species are gram-negative intracellular pathogens that cause bacillary dysentery in humans. Many genes required for virulence of Shigella are carried on a large 230 kb plasmid and many of these are under the transcriptional control of the histone-like nucleoid structuring protein (H-NS) and by the major virulence regulator VirB. At the non-permissive temperature of 30⁰C, H-NS represses transcription, while at 37⁰C VirB alleviates this repression. This mechanism of gene regulation has been coined "silencing/anti-silencing" and is commonly found in many important bacterial pathogens including Salmonella spp. and Yersinia spp. The icsP gene, encoded by the Shigella virulence plasmid, is …

Stereotype Threat’S Effect On Women’S Achievement In Chemistry: The Interaction Of Achievement Goal Orientation For Women In Science Majors, Janice M. Conway-Klaassen

UNLV Theses, Dissertations, Professional Papers, and Capstones

"Stereotype threat is being at risk of confirming, as a self-characteristic, a negative stereotype about one's group" (C. M. Steele & Aronson, 1995, p. 797). A stereotype threat effect then is described as the detrimental impact on a person's performance or achievement measurements when they are placed in a stereotype threat environment.

For women, the negative stereotype that exists in our culture states that women are typically not as capable as men in mathematics or science subjects. This study specifically explored the potential impact of stereotype threat on women who have chosen a science-based college major. They were tested in …

Use Of Task-Value Instructional Inductions For Facilitating Engagement And Conceptual Change, Marcus L. Johnson

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this study, 166 undergraduates from an Educational Psychology subject pool were randomly assigned to different task value instructional inductions (utility, attainment, and control) to determine whether inducing students with differing task values would be effective and result in different degrees of engagement for a learning task, as well as result in different degrees of conceptual change on the topic of the causes of the common cold. It was hypothesized participants would adopt characteristics that were consistent with the task value with which they were induced, that the participants in the utility, attainment, and control conditions would differ in their …

Evaluating The Impacts Of Water Conservation Policies On Water Demand, Availability And Outdoor Water Use In The Las Vegas Valley, Kamal Qaiser

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Las Vegas Valley, located in the arid Southern Nevada region, with a growing population, limited water resources, and a prolonged drought, faces a challenge in meeting its future water needs. Southern Nevada Water Authority (SNWA), the main water management agency in the Valley, is focusing on water conservation to reduce water demand. Current water use is 945 lpcd (250 gpcd) which SNWA aims to reduce to 752 lpcd (199 gpcd) by 2035. Presently the indoor outdoor water use proportion is about 40:60 in the Valley. An important component of the Valley's supply are the return flow credits which SNWA …

The Live Experience Of Non-Degree Learners From A Time Modified Traditional Baccalaureate In Nursing Program, Stephanie S. Deboor

UNLV Theses, Dissertations, Professional Papers, and Capstones

By the year 2016, it is projected that a million new and replacement nurses will be needed throughout the United States. The traditional 4-year baccalaureate program alone cannot adequately sustain this demand. The immediacy of the current nursing shortage demands our educational systems respond by building and maintaining a workforce that is sufficient to support the health care needs of our society. In an attempt to meet this challenge, nursing schools around the country began exploring the option of creating accelerated programs for those who already possess a bachelor's degree in another field without compromising the integrity and quality of …

Presenilin Is Necessary For The Function Of Cbp In The Adult Drosophila Cns, Randy S. Boyles

UNLV Theses, Dissertations, Professional Papers, and Capstones

Dominant mutations in Presenilin (Psn) have been correlated with the formation of Aß- containing plaques in patients with inherited forms of Alzheimer's disease (AD). However, a clear mechanism directly linking amyloid plaques to the pathology of familial or sporadic forms of AD has remained elusive. Thus, recent discoveries of several new substrates for Psn protease activity have sparked alternative hypotheses to explain the preclinical symptoms of AD. CBP (CREB-binding protein) is a haplo- insufficient transcriptional co-activator with histone acetyltransferase (HAT) activity that has been proposed to be a downstream target for Psn signaling. Individuals with reduced CBP levels have cognitive …

Alteration Of Microbial Communities Colonizing Leaf Litter In A Temperate Woodland Stream By Growth Of Trees Under Conditions Of Elevated Atmospheric Co2, John J. Kelly, Amit Bansal, Jonathan Winkelman, Lori R. Janus, Shannon Hell, Marie Wencel, Patricia Belt, Kevin A. Kuehn, Steven T. Rier, Nancy C. Tuchman

Faculty Publications

Elevated atmospheric CO₂ can cause increased carbon fixation and altered foliar chemical composition in a variety of plants, which has the potential to impact forested headwater streams because they are detritus-based ecosystems that rely on leaf litter as their primary source of organic carbon. Fungi and bacteria play key roles in the entry of terrestrial carbon into aquatic food webs, as they decompose leaf litter and serve as a source of nutrition for invertebrate consumers. This study tested the hypothesis that changes in leaf chemistry caused by elevated atmospheric CO₂ would result in changes in the size and …

Tongueless: Representation Of The Mentally Disabled And The Novel, Brent Walter Cline

Dissertations

This study examines the representation of the mentally disabled in the novel for two related outcomes. The first is to prove that the representation of the mentally disabled is not merely a subset of the representation of the disabled in general. This is intended less as a political statement as it is a literary one. Acknowledging and building off the work of writers in disability studies such as David Mitchell, Sharon Snyder, and Tobin Siebers who concentrate on the body of the disabled, this study shows that attempts to represent the mentally disabled are fundamentally different than those who are …

Lgb-Affirmative Therapists' Use Of Developmental Models Of Lgb-Identity In Therapy. A Phenomenological Investigation, Victoria E. Cane

Dissertations

Socially sanctioned hostility toward sexual minority persons continues to be a reality in the United States and worldwide. Therapists working with sexual minorities have responsibility to provide non-pathologizing, affirmative therapy to these clients. A central aspect of affirmative therapy is therapists' recognition and understanding of sexual orientation (SO) identity and developmental models of sexual minority identity have a played a vital role in promoting this understanding. Although such models have been central to the practice and training of affirmative therapy, therapists' applied use of the models has not been empirically investigated. For this phenomenological study, nine affirmative therapists were interviewed …

Gold Nanoparticle - Modified Zinc Oxide Nanoparticles As Novel Photocatalytic Materials, Nayane Udawatte

Dissertations

The current study entails the construction of a novel nano-composite catalyst based on ZnO and Au nanoparticles and demonstrates its distinctive photocatalytic characteristics. Monodisperse gold nanoparticles (GNPs) passivated with monolayers of tiopronin or glutathione were synthesized via facile methods, and they were assembled on ZnO nanoparticles to form the nanocatalyst.

Steady state and time resolved photoluminescent studies on the nanocomposite revealed interesting charge transfer characteristics within the nanocomposite. Enhanced photooxidation of rhodamine 6G was observed for the nano-composite over bare ZnO, and modulation of photoactivity with the extent of GNP loading was illustrated. Photoreduction of thionine over the nanocomposite was …

Contribution Of Membrane Elastic Energy To Rhodopsin Function, Olivier Soubias, Walter E. Teague, Kirk G. Hines, Drake C. Mitchell, Klaus Gawrisch

Physics Faculty Publications and Presentations

We considered the issue of whether shifts in the metarhodopsin I (MI)-metarhodopsin II (MII) equilibrium from lipid composition are fully explicable by differences in bilayer curvature elastic stress. A series of six lipids with known spontaneous radii of monolayer curvature and bending elastic moduli were added at increasing concentrations to the matrix lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and the MI-MII equilibrium measured by flash photolysis followed by recording UV-vis spectra. The average area-per-lipid molecule and the membrane hydrophobic thickness were derived from measurements of the 2H NMR order parameter profile of the palmitic acid chain in POPC. For the series of ethanolamines …

Teaching For Social Justice With Students From Privileged Groups: Integrating Social Justice Into Middle School Curriculum, Bong Seok Jang

Boise State University Theses and Dissertations

This dissertation research focuses on the teaching for social justice with privileged middle school students. A need for this research was established based on the limited findings specific to teaching for social justice in mathematics.

This research was implemented with junior high level students in a public charter school. The socio-economic status and ethnic diversity of the class in which this study took place is primarily middle to upper middle class and ten percent nonwhite.

Qualitative research methods were used because this study focuses more on human interactions in the natural setting of a classroom. First, my observations of the …

The Elderly Somali Bantu Experience Of American Health Care: The New Way, Cathy Marie Deckys

Boise State University Theses and Dissertations

A paucity of research exists involving the emic, or insider perspective, of the elderly Somali Bantu as it pertains to their experience of health care.  The purpose of this qualitative, descriptive study is to gain insight into the factors that influence the elderly Somali Bantus’ experience of American health care in Boise, Idaho based on their perspective.  The elderly Somali Bantu refugee has experienced many changes since their resettlement to the United States from United Nations’ refugee camps in Kenya four to seven years ago.  The majority of this population is illiterate and has no native written language.  This is …

Aryl Boronic Acid Inhibition Of Synthetic Melanin Polymerization, Jason M. Belitsky

Faculty & Staff Scholarship

Inhibitors of melanin formation are sought after for a range of applications. Boronophenylalanine is known to inhibit melanogenesis via boronic acid-catechol interactions. A spectroscopic assay was developed to study the polymerization of L-dopa to synthetic melanin in the presence of para-substituted aryl boronic acids. The best inhibition was observed for aryl boronic acids with electron-withdrawing substituents. The IC50 values exhibit a correlation with the Hammett sigma(p) parameter (rho = 0.97, r(2) = 0.92).

Macrophages Loaded With Gold Nanoshells For Photothermal Ablation Of Glioma: An In Vitro Model, Amani Riad Makkouk

UNLV Theses, Dissertations, Professional Papers, and Capstones

The current median survival of patients with glioblastoma multiforme (GBM), the most common type of glioma, remains at 14.6 months despite multimodal treatments (surgery, radiotherapy and chemotherapy). This research aims to study the feasibility of photothermal ablation of glioma using gold nanoshells that are heated upon laser irradiation at their resonance wavelength. The novelty of our approach lies in improving nanoshell tumor delivery by loading them in macrophages, which are known to be recruited to gliomas via tumor-released chemoattractive agents. Ferumoxides, superparamagnetic iron oxide (SPIO) nanoparticles, are needed as an additional macrophage load in order to visualize macrophage accumulation in …

Maintaining The Faith: Factors That Promote A Muslim Religious Identity, Majdouline Aziz

All Dissertations

Utilizing data collected from 194 past and present members of Muslim Student Associations located across the United States, this study examined predictors of Muslim religious identity. Multivariate linear regression analysis was used to examine the relationship between Muslim religious identity and self-identification, sense of belonging, affirmation, religious involvement in ritual practices, family characteristics, peer characteristics, structured organizational involvement, area of residence, college, and the experience of a terror event such as September 11, 2001. Hierarchical regression analysis was used to assess whether the experience of a terror event explained a significant proportion of the variance in Muslim religious identity. The …

The Mechanical Stress–Strain Properties Of Single Electrospun Collagen Type I Nanofibers, Christine C. Helms, Corentin Coulais, Martin Guthold

Physics Faculty Publications

Knowledge of the mechanical properties of electrospun fibers is important for their successful application in tissue engineering, material composites, filtration and drug delivery. In particular, electrospun collagen has great potential for biomedical applications due to its biocompatibility and promotion of cell growth and adhesion. Using a combined atomic force microscopy (AFM)/optical microscopy technique, the single fiber mechanical properties of dry, electrospun collagen type I were determined. The fibers were electrospun from a 80 mg ml⁻¹ collagen solution in 1,1,1,3,3,3-hexafluro-2-propanol and collected on a striated surface suitable for lateral force manipulation by AFM. The small strain modulus, calculated from three-point …

Meiotic Insurance: Designing A System To Study Crossover Control In Yeast, Kate V. Karfilis

Master's Theses

Meiosis is a specialized form of cell division in which haploid gametes are produced from diploid progenitors. This reduction in ploidy results from proper meiotic chromosome segregation and is ensured by crossover recombination events. Given their importance, it is no surprise that crossover formation is regulated in most eukaryotes. Crossover assurance is a regulatory mechanism that helps to ensure that each pair of chromosomes gets at least one crossover during meiosis.

We seek to better understand how crossover assurance works. To do so, we have developed a system in which crossover formation between a pair of chromosomes is restricted to …

Integration Of Microfluidics With Surface Plasmon Resonance, Scott B. Fratzke

Master's Theses

This thesis successfully integrates laminate microfluidic devices with an analytic Surface Plasmon Resonance (SPR) instrument. Integration was accomplished at low-cost using materials such as polydimethylsiloxane (PDMS), Poly(methyl methacrylate) (PMMA), Tygon tubing, and a 3-way stopcock. The main components of this thesis are the design and fabrication of the low-cost, in-house fluidics that can integrate with upstream microfluidics and the validation of the in-house fluidics using the Biosensing Instruments BI-2000 SPR instrument. The low-cost fluidics was designed and fabricated “in-house” using a novel investment casting technique that required the use of laser cutting technology to make a master cast, and candle …

Grown Men, Daniel Charles Crocker

Dissertations

Grown Men is a collection of short fiction that articulates the themes of poverty, adulthood, alcoholism and faith. Some of the stories use the same characters in order to further explore place and economic and social status. Set in small towns in Missouri and Mississippi, Grown Men seeks to examine the way men deal with their changing roles when they lose their jobs, relationships and families. The collection is accompanied by a critical introduction. ii

Assessing Mississippians’ Preparedness For Disasters Using The Citizen Corps National Survey 2009, Carl Huston Mangum Ii

Dissertations

Disaster preparedness, a shared responsibility of all citizens and disaster agencies, is the most critical component in minimizing risk and damage from disaster. Mississippi has been affected by some of the most devastating disasters in American history, both in terms of physical destruction and human life. The purpose of this study was to assess Mississippians’ disaster preparedness by replicating The 2009 Citizen Corps National Survey (CCNS). The 65 question 2009 CCNS was slightly modified to survey 678 randomly selected Mississippians about the Citizen Corps Personal Disaster Preparedness Model: Demographics, Volunteering, Drills/Exercises, Community Plan, Household Plan, Disaster Supplies, Prevention, Self-efficacy, Reliance, …

Synthesis And Characterization Of Monolayer Protected Gold Nanoparticles And A Gold-Titanium Dioxide Nanocomposite Intended For Photocatalytic Degradation Of Environmental Pollutants, Piyadarsha Amaratunga

Dissertations

Semiconductor and metal clusters in the nanometer size regime display interesting optical, electronic and chemical properties that are size dependant. Highly monodisperse gold nanoparticles of different sizes have been synthesized and isolated by newly developed methodologies, using tiopronin as the capping ligand. Titanium dioxide nanoparticles (Ti0₂) have been used as the photocatalytic center and gold nanoparticles have been attached on Ti0₂ to make a nanocomposite. According to the findings, gold nanoparticles play a vital role in enhancing the photocatalytic activity of Ti0₂, by facilitating the charge separation. Further, the photocatalytic activity also can be tuned …

Development Of A Task Assignment Tool To Customize Job Descriptions And Close Person-Job Fit Gaps, Bryan W. Booker

Dissertations

Does the knowledge worker fit the job or should the job fit the knowledge worker? This research developed a methodology and a tool to customize a knowledge worker’s job design to better fit their knowledge, skills, abilities and characteristics. The research outcomes support the customization of the job design to improve person-job fit, the documentation of the customized job design as a position description, and the use of a structured person-task assignment process. The recommended task assignment process includes a job aid that uses multivariate equations to predict expected task performance. Data were collected from two knowledge worker sub-groups: lean …

Malware Type Recognition And Cyber Situational Awareness, Thomas E. Dube, Richard A. Raines, Gilbert L. Peterson, Kenneth W. Bauer, Michael R. Grimaila, Steven K. Rogers

Faculty Publications

Current technologies for computer network and host defense do not provide suitable information to support strategic and tactical decision making processes. Although pattern-based malware detection is an active research area, the additional context of the type of malware can improve cyber situational awareness. This additional context is an indicator of threat capability thus allowing organizations to assess information losses and focus response actions appropriately. Malware Type Recognition (MaTR) is a research initiative extending detection technologies to provide the additional context of malware types using only static heuristics. Test results with MaTR demonstrate over a 99% accurate detection rate and 59% …