Life Sciences Commons^™

Measuring Population Transmission Potential For Hiv: An Alternative Metric Of Transmission Risk In Men Who Have Sex With Men (Msm) In The Us, Colleen F. Kelley, Eli S. Rosenberg, Brandon M. O'Hara, Paula M. Frew, Travis Sanchez, John L. Peterson, Carlos Del Rio, Patrick S. Sullivan

Environmental & Occupational Health Faculty Publications

Background Various metrics for HIV burden and treatment success [e.g. HIV prevalence, community viral load (CVL), population viral load (PVL), percent of HIV-positive persons with undetectable viral load] have important public health limitations for understanding disparities. Methods and Findings Using data from an ongoing HIV incidence cohort of black and white men who have sex with men (MSM), we propose a new metric to measure the prevalence of those at risk of transmitting HIV and illustrate its value. …See full text for complete abstract.

Effects Of Flight On Gene Expression And Aging In The Honey Bee Brain And Flight Muscle, Joseph Margotta, Georgina E. Mancinelli, Azucena A. Benito, Andrew Ammons, Stephen P. Roberts, Michelle M. Elekonich

Life Sciences Faculty Research

Honey bees move through a series of in-hive tasks (e.g., “nursing”) to outside tasks (e.g., “foraging”) that are coincident with physiological changes and higher levels of metabolic activity. Social context can cause worker bees to speed up or slow down this process, and foragers may revert back to their earlier in-hive tasks accompanied by reversion to earlier physiological states. To investigate the effects of flight, behavioral state and age on gene expression, we used whole-genome microarrays and real-time PCR. Brain tissue and flight muscle exhibited different patterns of expression during behavioral transitions, with expression patterns in the brain reflecting both …

Moving Forward: Preventing Water Shortage For Nevada, Sandra Blandon, Brianna Lyon

COLA 100: Feast and Famine In a Global World Poster Assignment

Southern Nevada is located in the arid Mojave Desert, which averages about 4 inches of rain each year. Southern Nevada gets about 90% of its water supply from the Colorado River. Seven western states and Mexico share the river. This means that The Colorado River provides water to 25 million people.

Shock Attenuation In Landing, Bryon Christopher Applequist

UNLV Theses, Dissertations, Professional Papers, and Capstones

Shock attenuation (SA) has been well studied in activities such as walking and running (Chu, et al. 2004; Derrick, et al. 2004; Mercer, et al. 2003); however, there is a lack of research regarding SA during landing. Furthermore, there is lack of information regarding which structures attenuate shock. The purpose of this study was to examine SA among the leg-hip, hip-head, and leg-head segments during landing. Each subject (n=10, Age 26.3 ± 2.71 years, Height 1.68 ± 0.08 m, Mass 70.49 ± 16.03 kg) was instrumented with accelerometers at the leg, hip and forehead. Subjects then performed landings from three …

Restoration Of Biological Soil Crust On Disturbed Gypsiferous Soils In Lake Mead National Recreation Area, Eastern Mojave Desert, Lindsay P. Chiquoine

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biological soil crusts (BSCs) are sensitive to anthropogenic disturbances. Natural recovery takes many years. Active restoration decreases recovery time. Native BSC inocula, which included lichens and mosses, salvaged from gypsiferous soil habitats in Lake Mead National Recreation Area (LMNRA) in the eastern Mojave Desert were stored dry for two years and applied to disturbed soil after a road reconstruction in LMNRA and also used in laboratory experiments to test inoculation technique effectiveness. After 18 months, field results revealed positive relationships between inoculation and the presence of macroscopic BSC cover, cyanobacteria abundance, soil stability, and ammonium concentrations. Chlorophyll fluorescence monitoring of …

Anti-Germinants As A New Strategy To Prevent Clostridium Difficile Infections, Amber Janece Howerton

UNLV Theses, Dissertations, Professional Papers, and Capstones

Clostridium difficileinfections (CDI) have emerged as a leading cause of hospital-associated complications. CDI is the major cause of antibiotic-related cases of diarrhea and nearly all cases of pseudomembranous colitis. The infective form of C. difficileis the spore, a dormant and hardy structure that forms under stress. Germination of C. difficile spores into toxin producing bacteria in the GI tract of susceptible patients is the first step in CDI establishment. Patient susceptibility occurs with a disruption of the natural gut microbiota by broad-spectrum antibiotics. Antibiotic treatments usually resolve CDI but refractory cases are on the rise. Of great concern is the …

Characterization Of Beryllium As A Novel Agent To Study Cell Cycle Arrest And Cellular Senescence, Priyatham Gorjala

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cancer cells evade senescence, apoptosis, and other constraints on proliferation, often via mutation of the p53 tumor suppressor gene (TP53). Normal human lung fibroblasts have been shown to enter premature senescence upon exposure to beryllium. In these cells, BeSO₄ stabilizes p53 protein, increases p21 gene expression, induces senescence-associated β-galactosidase activity and causes cell proliferation arrest. In the present study, we have investigated whether BeSO₄ is able to induce similar effects in cancer cells that have wildtype p53. We have demonstrated that beryllium salt at low concentration can induce molecular changes in the p53 signaling pathway leading to cell …

Secondary Structure, A Missing Component Of Sequence- Based Minimotif Definitions, David P. Sargeant, Michael R. Gryk, Mark W. Maciejewsk, Vishal Thapar, Vamsi Kundeti, Sanguthevar Rajasekaran, Pedro Romero, Keith Dunker, Shun-Cheng Li, Tomonori Kaneko, Martin Schiller

Life Sciences Faculty Research

Minimotifs are short contiguous segments of proteins that have a known biological function. The hundreds of thousands of minimotifs discovered thus far are an important part of the theoretical understanding of the specificity of protein-protein interactions, posttranslational modifications, and signal transduction that occur in cells. However, a longstanding problem is that the different abstractions of the sequence definitions do not accurately capture the specificity, despite decades of effort by many labs. We present evidence that structure is an essential component of minimotif specificity, yet is not used in minimotif definitions. Our analysis of several known minimotifs as case studies, analysis …

Nitrite Oxidation In Geothermal Springs: Evidence Of An Upper Temperature Limit For Thermophilic Nitrite-Oxidizing Bacteria Of 60 - 65 °C, Tara Edwards

UNLV Theses, Dissertations, Professional Papers, and Capstones

Despite growing evidence of the importance of nitrification in terrestrial geothermal environments, little is known about nitrite oxidation in these environments. In order to further our knowledge, this study combined cultivation-dependent and -independent approaches with measurements of nitrogen speciation along the outflow channels of two Great Basin geothermal springs. Enrichment cultures were inoculated with sediment slurries from sites ranging in temperature from 42 - 87 °C at the sources and along the outflows of >15 hot springs. While attempts to enrich nitrite-oxidizing bacteria (NOB) from sites greater than or equal to 61 °C were unsuccessful, NOB were enriched from five …

Evaluation Of The Tagelus® Ta 100d Sand Filter For Removing Quagga Mussel Veligers (Dreissena Rostriformis Bugensis) From Lake Water And The Effectiveness Of The Safeguard Ultraviolet Radiation System As A Biocide Against Veligers, Patricia Kathleen Delrose

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Lake Mead National Recreational Area was created by the construction of the Hoover Dam during the years 1931-1936. In January 2007, the quagga mussel (Dreissena rostriformis bugensis), was found in Lake Mead. This became the first known Dreissenid species in the southwest and the only time a large water system was first infested by the quagga mussel and not the zebra mussel (Dreissena polymorpha). This invasive species has quickly spread to Lake Mohave and further down the lower Colorado River drainage. The microscopic size (70 µm or larger) of the veliger life stage makes it impossible to see with …

Dreissena Rostiformis Bugensis: Desiccation Of Adult Quagga Mussels Found In Lake Mead As A Preventive Measure Against Overland Dispersal In The Western United States, Matthew Kappel

UNLV Theses, Dissertations, Professional Papers, and Capstones

The expansion of civilization across all borders of the world has proven to affect major components of ecosystems. Since the introduction and establishment of the aquatic invasive species (AIS),Dreissena rostiformis bugensis, commonly known as the quagga mussel, into the United States there has been an extensive amount of time and money spent on controlling and preventing their expansion across the United States. The quagga mussel is of major concern because of its ability to disrupt the ecological communities in previously non-infested bodies of water, which may cause a loss in biodiversity and effect environmental health. The quagga mussel has spread …

Natural And Lignocellulose-Enriched Microbial Communities In Great Boiling Spring, Nv, Jessica Cole

UNLV Theses, Dissertations, Professional Papers, and Capstones

The natural microbial communities present in Great Boiling Spring were investigated and contrasted against those present after in situ enrichment with lignocellulose. High-throughput cultivation-independent DNA sequencing of the V8 region of the small subunit (SSU) rRNA gene generated a total of 274,119 quality-filtered pyrosequencing fragments. Twelve natural spring samples were analyzed, including four high-temperature water samples and eight sediment samples ranging from 87 - 62 °C. Eight lignocellulosic enrichments incubated in the spring sediment and water at two high-temperature sites were analyzed. The natural water communities were found to be extremely uneven but relatively constant throughout time. The natural sediment …

A Genetic, Transgenic, And Transcriptomic Analysis Of Larval Salivary Gland Physiology In Drosophila Melanogaster, Elana A. Paladino

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cholesterol is the precursor to a unique class of lipophilic signaling molecules called steroid hormones that initiate the development of sexual characteristics, reactions to stress, and maintenance of metabolism, among many other functions. Although much progress has been made in understanding the function of these signaling hormones, we do not fully understand how a single steroid can cause many distinct, tissue-specific responses. Drosophila melanogaster is an effective model for understanding steroid hormone action because of its simplicity. The steroid molting hormone 20-hydroxyecdysone (hereafter, 20E) is the primary active steroid in Drosophila and mediates not only larval molts and the emergence …

The Abundance And Distribution Pattern Of Quagga Mussels In The Las Vegas Bay Of Lake Mead, Nevada And Potential Correlation With Environmental Parameters, Scott Rainville

UNLV Theses, Dissertations, Professional Papers, and Capstones

The non-native quagga mussel [Dreissena bugensis (Andrusov, 1897)] was initially discovered in Boulder Basin of Lake Mead, Nevada-Arizona on January 6, 2007. This occurrence marked the first biological invasion of dreissenid mussels in the Western U.S., following a significant North American range expansion of invasive quagga mussels from populations that invaded and colonized the Great Lakes Region in the Northeastern U.S. during 1991. This nonindigenous mollusk species quickly spread from Boulder Basin and became established throughout the entire reservoir by the end of 2007, with the exception of the inner Las Vegas Bay. There was an apparent absence of settled …

The Impact Of Creosote Bush (Larrea Tridentata) And Biological Soil Crust On Ca Distribution In Arid Soils Of The Mojave Desert, Brittany Myers

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ca is an important nutrient that plays a role in membrane stability and cell repair in plant life. This study examines the impact of creosote bush (Larrea tridentata) and biological soil crust on calcium cycling and distribution in desert soils in order to explore the use of Ca as a biosignature. Samples of creosote bush, biological soil crust and eolian dust were taken at two field sites in the Mojave Desert. The first site is located in Eldorado Valley, NV, a soil formed on a young (800-1200 years) alluvial fan deposit; the second site is located on a late Holocene-aged …

Frictional Forces Of A Fixed, Esthetic Orthodontic Appliance System, Brady Michael Nance

UNLV Theses, Dissertations, Professional Papers, and Capstones

Purpose: The demands of an all esthetic fixed orthodontic appliance system are ever increasing in today's world. Frictional values of an esthetic, fixed orthodontic appliance system are needed to evaluate their clinical effectiveness for orthodontic treatment. The aim of this study is to evaluate the frictional values of various esthetic orthodontic archwires ligated to an esthetic orthodontic bracket.

Methods: Three types of stainless steel and nickel titanium alloy (niti) esthetic orthodontic archwires (epoxy, poly, plastic) in four sizes (.016, .018, .017 x .025, .019 x .025 inches) were ligated to both a stainless steel bracket system and a ceramic (esthetic) …

Protecting Children From Overexposure To Lead In Candy And Protecting Children By Lowering The Blood Lead “Level Of Concern” Standard, Bryan Wagner, Colleen C. Hughes, Robert Sobsey

Nevada Journal of Public Health

The American Public Health Association: Recognizing that in April 2004, the Orange County Register in an investigative report, published for the first time information that the state of California had been testing for lead in candies for decades but had not informed the public about the high lead levels in many candies, candy wrappers and seasonings (sold as a snack item and consumed as candy) imported from Mexico, the Philippines and other countries.

Findings From The Nutrition Challenge Program, Rayleen Earney, Nicole Bungum, Timothy J. Bungum

Nevada Journal of Public Health

Obesity is an epidemic in the United States. Over 61% of U.S. adults and 58% of Nevada adults have Body Mass Index’s (BMI) that classify them as either overweight or obese (Behavioral Risk Factor Surveillance System [BRFSS], 2005). According to a recent article published in the Journal of the American Medical Association, obesity was the second leading cause of preventable death in the United States behind tobacco use (Mokdad, Marks, Stroup & Gerberding, 2004).

While obesity and overweight are complex, multi-factorial health conditions, an important contributor to the overweight and obesity epidemic is poor dietary habits. One of the major …

A Study To Determine If University Athletic Teams In Desert Environments Experience Risky Diet-Related Behaviours, Susan Meacham, Christine Bergman, Marcia M. Ditmyer, Kyle Wilson, Connie Mobley

Nevada Journal of Public Health

Training and competing in desert environments may exacerbate concerns related to disordered eating, supplement use, and hydration in some student athlete populations. A survey administered equitably to both genders solicited self-reported responses from members of 18 different teams over four years from a southwestern United States university athletic program. More than 1,700 athletes responded to 42 items on the questionnaire. Teams, not individual student athletes, were the units of measure for statistical analyses. Initial analysis of results indicated that there were no overt concerns regarding dietary behaviors due to training and competing in the desert environment. Further analysis subjected the …

The Effects Of Television Food Advertising On Childhood Obesity, Aleathia Cezar

Nevada Journal of Public Health

Children’s food choices are influenced by the media, television advertising, focusing directly at infants and toddlers. This literature review presents multiple studies that explain how TV advertising of fast food, sugary cereals and other foods high in calories, fat, sugar, sodium and low in nutrients are contributing to the increase rates of childhood obesity. It is concluded that children are exposed to high amounts of food advertisements which affect young children’s food choices and poor food consumption. Due to the growing numbers of hours that children sit in front of the television, less physical activity and the epidemic of childhood …

Carbohydrate Consumption And Fatigue: A Review, Jennifer R. Pharr

Nevada Journal of Public Health

Fatigue is a condition that negatively impacts quality of life and occurs in about twenty four percent of adults worldwide. Many factors may contribute to fatigue. One factor is the macronutrient composition of a person’s diet, particularly, the amount of simple carbohydrates. This paper is a review of the current literature and examines the relationship of carbohydrate consumption and fatigue to determine if a diet low in simple carbohydrates results in an improvement in fatigue ratings. Results of studies regarding carbohydrate consumption and fatigue vary, the preponderance demonstrate a positive relationship between simple carbohydrate consumption and fatigue. Additionally, diets low …

Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending September 30, 2012, Margaret N. Rees

Limnological Studies

Continuation of Project 1

• The research effort titled Growth of adult quagga mussels within Las Vegas Wash/Las Vegas Bay is ongoing.

Continuation of Project 2

• Additional content was contributed to the future NPS-funded U.S. Geological Survey Circular ‘state-of-the-science’ report for Lakes Mead and Mohave. UNLV performed a new co-editing and coordinating task related to this product as the major focus of this quarter’s effort; the master version of this report is on schedule for delivery to the editorial team during the first week of October 2012.

Modification Activities:

Extended Short-term Continued Limnological Assistance

Quagga Mussel Objectives:

• Most juvenile/adult quagga mussel …

Health Disparities Experienced By People With Disabilities In The Us: A Behavioral Risk Factor Surveillance System Study, Jennifer Renee Pharr, Timothy J. Bungum

Environmental & Occupational Health Faculty Publications

The Americans with Disabilities Act became law in 1990; since then research has shown that people with disabilities continue to experience barriers to health care. The purpose of this study was to compare utilization of preventive services, chronic disease rates, and engagement in health risk behaviors of participants with differing severities of disabilities to those without disabilities. This study was a secondary analysis of 2010 data collected in the Behavioral Risk Factor Surveillance System national survey in the United States. Rao Chi square test and logistic regression were employed. Participants with disabilities had significantly higher adjusted odds ratios for all …

Achieving High Accuracy Prediction Of Minimotifs, Tian Mi, Sanguthevar Rajasekaran, Jerlin Camilus Merlin, Michael R. Gryk, Martin Schiller

Life Sciences Faculty Research

The low complexity of minimotif patterns results in a high false-positive prediction rate, hampering protein function prediction. A multi-filter algorithm, trained and tested on a linear regression model, support vector machine model, and neural network model, using a large dataset of verified minimotifs, vastly improves minimotif prediction accuracy while generating few false positives. An optimal threshold for the best accuracy reaches an overall accuracy above 90%, while a stringent threshold for the best specificity generates less than 1% false positives or even no false positives and still produces more than 90% true positives for the linear regression and neural network …

Effects Of Moisture Augmentation Of Municipal Solid Waste Through Addition Of Food Waste Or Wastewater Treatment Biosolids On Bio-Gas Formation For Power Generation, Jared Michael Gore

UNLV Theses, Dissertations, Professional Papers, and Capstones

An investigation into the effect of moisture augmentation by manipulation of food waste proportion or wastewater treatment plant biosolids proportion was undertaken to determine the effects on production of methane and other biogases from municipal solid waste (MSW). Laboratory microcosm experiments were performed to determine the effect of various proportions of influent waste streams on the production of biogas. Results indicated that moisture augmentation through the addition of food waste to MSW increases the overall bio-gas and hydrogen gas formed during fermentation. Moisture augmentation through addition of wastewater treatment bio-solids lead to inconclusive results. Addition of food waste to MSW …

Scorpion Phylogeography In The North American Aridlands, Matthew Ryan Graham

UNLV Theses, Dissertations, Professional Papers, and Capstones

Understanding the geographic, geologic, and climatic forces responsible for generating current patterns of biodiversity has been a central objective of phylogeography. To develop a better understanding of these processes in the North American arid lands, I used DNA sequence data and species distribution modeling to conduct three phylogeographic assessments incorporating four species of arid-adapted scorpions:Hadrurus arizonensis, H. jedediah, H. spadix,and Paruroctonus becki. In an assessment of H. arizonensis, phylogeographic patterns indicate that Pleistocene climate cycles and associated glacial refugia played a central role in structuring the genetic diversity of this species in the Mojave and Sonoran deserts, mostly supporting predictions …

Effects Of Positive Feedback On Oxygen Consumption And Heart Rate During A 3-Minute Step Test, Leighann Dewitt

UNLV Theses, Dissertations, Professional Papers, and Capstones

The positive effects of enhanced expectancies on motor performance and learning have been demonstrated by numerous studies. A more recent study by Stoate, Wulf, and Lewthwaite (2012) showed than enhancing one's expectancy by giving positive feedback increased movement efficiency and decreased oxygen consumption in experienced runners during a 20 minute running test at 75% of max oxygen consumption, compared to those who received no feedback. The purpose of the present study was to test if enhancing expectancies can improve movement efficiency (i.e., reduce oxygen consumption) during a sub-maximal exercise test. Participants were randomly assigned to one of two groups, enhanced …

Unintentional Home Injury Risks Among The Elderly In Southern Nevada, Michelle Echauz Ching

UNLV Theses, Dissertations, Professional Papers, and Capstones

The elderly population (65 years of age and older) is one of the fastest growing populations in the US. A major public health concern involving the elderly population is unintentional injuries in the home. Since elderly adults typically spend the majority of their time in the home, minimizing unintentional home injury hazards is crucial for this population. The Nevada Healthy Homes Partnership (NHHP) program is a grant funded effort that helps to improve the quality and availability of safe and healthy homes in Nevada. Therefore, the purpose of this study is to determine the effectiveness of the NHHP program interventions …

The Effect Of Footwear On The Mechanics Of The Lower Back During Treadmill Running, Jeffrey Ray Mcclellan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Little is known regarding the effect that footwear cushioning can have on the mechanics of the low back. The purpose of this study was to 1) determine the material characteristics of a minimalist running shoe tested with and without a commercially available shoe insole, 2) determine if there are differences in lower back or knee kinematics when minimalist shoes are worn with and without a shoe insole during treadmill running, and 3) determine if there are differences in levels of muscle activation when minimalist shoes are worn with and without a shoe insole during treadmill running. Following the receipt of …

Effects Of Controlling Versus Autonomy-Supportive Language On Learning A Novel Motor Skill And Cortisol Release, Andrew Mcmahon Hooyman

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to compare how different types of instruction effect the learning of a novel motor skill and how salivary cortisol correlates to learning differences. Participants (N = 44), average age 22.3 years (standard deviation 2.37), were randomly assigned to an autonomy-supportive, controlling-language or neutral language group which was manipulated via instructional video. Saliva was collected before and after each session, and questionnaires were given after pitching was completed during each day. Results showed that there was a significant difference among groups in throwing accuracy on performance and retention. Questionnaire results also showed significant group differences …