Life Sciences Commons^™

Characterization Of Beryllium Ion Complexation In The Presence Of Biological Buffers Using Isothermal Titration Calorimetry, Guillermo Alexander Ramirez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Be2+ ion is a biologically active metal that is capable of binding to proteins and has been shown to affect various cellular processes. When treated with Be2+, certain cancer cells display cytostatic effects. GSK3β is a regulatory kinase involved in the β-catenin pathway that may be involved in producing these cytostatic effects when Be2+ binds to it. In order to determine binding parameters between Be2+ and GSK3β, isothermal titration calorimetry (ITC) can be utilized. However, titrations at physiological pH cannot be carried out due to Be2+ unique speciation at neutral pH ranges. Significant precipitation occurs at pH 6 and higher …

Investigating The Mechanisms Responsible For Cephalosporin Resistance In Clostridioides Difficile Strain 630, Lara Anna Turello

UNLV Theses, Dissertations, Professional Papers, and Capstones

Clostridioides difficile infection (CDI) is one of the most common nosocomial infections worldwide. A major risk factor for CDI is antibiotic therapy, due to C. difficile’s resistance to a myriad of antibiotics—one of which are cephalosporins. Cephalosporins are ß-lactam antibiotics that function by binding to the active site of penicillin-binding proteins (PBPs), thus inhibiting peptidoglycan synthesis and leading to cell lysis. Gram-positive bacteria can counteract ß-lactams by (i) producing ß-lactamases, (ii) expressing modified PBPs, or (iii) by expressing efflux pumps.

Genomic analysis of C. difficile strain 630 revealed the presence of at least 31 putative ß-lactam resistance genes that encode …

Paleoecology Of Columbian And Pygmy Mammoths In Southern Nevada And California: How Terminal Pleistocene Ecosystems Shaped Mammoths At The Individual, Population, And Community Level, Lauren Elizabeth Parry

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this dissertation research is to examine the paleoecology of the Columbian mammoth (Mammuthus columbi) and the pygmy mammoth (M. exilis) on the individual, population, and community level, emphasizing factors internal to their ecosystem that may have contributed to their extinction. I focus specifically on mammoths from Southern Nevada and Southern California to add regional data to the complex and evolving study of North American mammoth paleoecology.

Chapter 2 documents the permitted excavation of a partial mammoth (Mammuthus sp.) between 2016-2018 from late Pleistocene groundwater-discharge deposits near Fairbanks Spring in the Amargosa Valley, Nevada. A preliminary radiocarbon date …

The Relationship Between Tree Canopy And Social Capital On Physical Activity In Unlv Students, Melissa Bartshe

UNLV Theses, Dissertations, Professional Papers, and Capstones

Despite the numerous health benefits, rates of physical activity are low, especially among the college student population. Neighborhood tree canopy is one aspect of the built environment that has been shown to positively impact physical activity. Social capital has also been correlated with higher rates of physical activity. The sprawling urban design and arid desert climate of Las Vegas pose unique challenges to both tree canopy and social capital. Additionally, the relationship between tree canopy, social capital, and physical activity is understudied in the college student population. The purpose of this study was to assess the relationship of tree canopy …

Oral Localization Of Scardovia Wiggsiae, Graydon Ramos Carr

UNLV Theses, Dissertations, Professional Papers, and Capstones

Early childhood caries is one of the most prevalent diseases in the United States among children. The formation of caries is a complex, multifactorial process that is still being studied. Researchers have thought for years that Streptococcus mutans was the primary causative agent of early childhood caries. The recent discovery of a novel cariogenic pathogen, Scardovia wiggsiae and its significant contribution to the etiology of early childhood caries has led oral health researchers to re-evaluate this microorganism and its link to this disease. While there have been several projects undertaken within the University of Nevada, Las Vegas School of Dental …

Utilizing Breathing Techniques To Maximize Training Performance, Peyton Cater

UNLV Theses, Dissertations, Professional Papers, and Capstones

Anaerobic exercise causes metabolic acidosis to occur in the muscle, which is unfavorable for sustaining high intensity activity, as fatigue starts to set in. In order to compensate for the onset of fatigue produced by an acidic environment, respiratory alkalosis, induced by hyperventilation, can be performed to mitigate these effects. In contrast, research has shown that slowing down the breath rate, such as a two second inhale and three second exhale, has led to an increase in performance outcomes. Purpose: To investigate power output and the physiological responses after implementation of different breathing techniques during the recovery periods of intermittent …

Do Compression Garments Work? The Effect Of Compression Garments On Biomechanical And Physiological Factors, Andrew Craig-Jones

UNLV Theses, Dissertations, Professional Papers, and Capstones

New and innovative technology is consistently being introduced to help runners gain an edge over their competition. One of the more popular ergogenic aids in running today is compression garments. It is estimated that the compression garment market will surpass $5 billion by the year 2022. Despite the popularity, there is no clear consensus as to if or why compression is effective as an ergogenic aid. Although there has been a large variety of variables tested, there is little agreement on any of them as to the effect compression has. It appears as if the rate at which compression is …

Can Desert Mosses Hide From Climate Change? The Ecophysiological Importance Of Habitat Buffering & Water Relations To A Keystone Biocrust Moss In The Mojave Desert, Theresa Ann Clark

UNLV Theses, Dissertations, Professional Papers, and Capstones

Empirical and observational studies suggest a keystone biocrust moss, Syntrichia caninervis, may be sensitive to future climate change in the American Southwest due to its uniquely sensitive water relations that appear particularly challenged during summer hydration-desiccation cycles. However, the potential mitigating roles of habitat buffering, acclimatization, and winter recovery on the vulnerability of this species remain largely unexplored. I investigated potential abiotic and biotic resiliency factors driving summer stress resistance and recovery in S. caninervis along present-day aridity gradients in the Mojave Desert to strengthen the climate change vulnerability assessment for this species common to biocrusts of North America, northern …

Partitioning The Mechanical Cost Of Human Walking: Unveiling Cost Asymmetries For Bionic Technologies, Michael Richard Isaacs

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biomechanics studies over the past 150 years, suggest that animals, including humans, move at speeds that “optimize” their cost of transport. These optimizations can be metabolic, mechanical, or a mixture of the two; however, the consensus on the relationship between metabolic and mechanical cost has been muddied by our current conceptualizations of mechanical cost. Our prior considerations in assessing mechanical cost of transport for animal locomotion often rely upon the exchange of potential and kinetic energy for a rising and falling center of mass that is supported by rigid legs. As a result, our understanding of the mechanical costs associated …

The Influence Of G4 Dna Structures On Stationary Phase Mutagenesis In Bacillus Subtilis, Tatiana Ermi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Until the late 1980’s it was widely understood that bacterial variance emerges randomly during growth. Research that followed has convincingly shown evidence for mutations arising in non-growing conditions, a phenomenon known as stationary-phase mutagenesis. In Bacillus subtilis, an elegant mutagenic mechanism has been elucidated in non-growing cells that biases mutations to transcribed regions of a subpopulation. One interesting possibility is that mutations can be further biased to hotspots within genes through alternate DNA structures known as non-B DNA. Non-B DNA have been linked to genomic instability and disease in humans, lesser is known about its role in bacteria. Here we …

Rapid Detection Of Toxin-Producing Cyanobacteria, Timothy Alba

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lake Mead provides drinking water to millions of people in Nevada, California, and Arizona. In 2015, the Southern Nevada Water Authority detected the cyanobacteria-produced toxin microcystin in the lake for the very first time. This toxin is lethal in large doses, and in small doses it causes a myriad of serious health effects. Detecting microcystin directly is a time-consuming and expensive process that requires liquid chromatography tandem mass spectrometry or immunological analyses, which require a full day or more to process samples. In order to provide water managers with the methodology for a toxin monitoring plan, this work developed a …

The Significance Of Mfd And Oxidative Damage In Stationary-Phase Mutagenesis In Bacillus Subtilis, Holly Anne Martin

UNLV Theses, Dissertations, Professional Papers, and Capstones

The process of stationary-phase mutagenesis, also known as adaptative or stress-induced mutagenesis, is a phenomenon where bacterial cells accumulate mutations in non-replicative conditions. This process has mainly been studied in Escherichia coli and Bacillus subtilis; however, the underlying mechanisms found in each of these systems differ. Here, I use B.msubtilis to study previously understudied aspects of stationary-phase mutagenesis. In this dissertation, I describe work that has led to three major discoveries which are described below.

First in B. subtilis, Mfd is important for stationary-phase mutagenesis and its mutagenic function at regions of the genome that are transcriptionally upregulated has been …

Stereotactic Radiosurgery Implementation At Utah Valley Hospital, Ryan Sharp

UNLV Theses, Dissertations, Professional Papers, and Capstones

Utah Valley Hospital (UVH) implemented a stereotactic radiosurgery (SRS) program as an additional line of service. SRS as defined by the American College of Radiology is radiation therapy delivered via stereotactic guidance with approximately 1 mm targeting accuracy to intracranial targets in 1-5 fractions. Effectively implementing the SRS program at UVH requires the adoption and implementation of hardware and software technologies, a review of the clinical workflow with appropriate quality assurance tests, and the assessment of additional technologies that will further enhance the capabilities of the program. The scope of this work is to include a comprehensive writeup of the …

Respiratory And Perceptual Responses To High Intensity Interval Exercise In Obese Adults, Nicholas Andrew Ross

UNLV Theses, Dissertations, Professional Papers, and Capstones

Purpose: Obese adults experience low lung volume breathing at rest and during exercise, which provokes ventilatory constraints and dyspnea on exertion. High-intensity interval exercise (HIIE) has emerged as an alternative to continuous exercise (CE); however, the effects of HIIE on lung volumes, ventilatory constraints and dyspnea on exertion have not been studied in obese adults and thus tolerability of HIIE remains unknown. Therefore, the purpose of this study was to examine the differences in respiratory and perceptual responses during HIIE versus CE in obese adults when compared with nonobese adults. Methodology: Ten healthy, nonobese (24.1 ± 6.2 yr., BMI: 23 …

Validity And Reliability Of Three Commercially Available Smart Sports Bras During Treadmill Walking And Running, James W. Navalta, Gabriela Guzman Ramirez, Crystal Maxwell, Kara N. Radzak, Graham R. Mcginnis

Kinesiology and Nutrition Sciences Faculty Research

A variety of wearable technology devices report heart rate. Heart rate sensing smart bras are manufactured for females who participate in activity, however accuracy has not been determined. The purpose was to determine the validity of heart rate measures in three commercially available sports bras during walking and running. Twenty-four healthy females completed bouts of treadmill exercise. The Adidas Smart sports bra, Berlei sports bra, and Sensoria Fitness biometric sports bra were tested. Participant perception of each garment was obtained immediately after the participant divested the sports bra. The Adidas Smart sports bra was valid only during rest (Intraclass correlation …

Integrating The Functional Movement Screen ® Into Strength And Conditioning Programs, Quincy Johnson, Chantel C. Coleman, Timothy Baghurst

Topics in Exercise Science and Kinesiology

• The purpose of this article is to provide an overview of the Functional Movement Screen (FMS®) and how it can be integrated into strength and conditioning programs of all levels.
• We utilized current literature and previous FMS ® field experience to develop and recommend approaches for implementing FMS® protocols into strength and conditioning programs.
• Description of FMS® Movements: The FMS® is a comprehensive biomechanical efficiency screen which is comprised of seven movements that have been deemed fundamental to athletic performance (7). Those movements include the; deep squat, hurdle step, in-line lunge, shoulder mobility, active straight-leg raise, trunk stability push-up, and …

Insight On Thermal Stability Of Magnetite Magnetosomes: Implications For The Fossil Record And Biotechnology, Jefferson Cypriano, Mounib Bahri, Kassioge Dembele, Walid Baaziz, Pedro Leao, Dennis A. Bazylinski, Fernanda Abreu, Ovidiu Ersen, Marcos Farina, Jacques Werckmann

Life Sciences Faculty Research

Magnetosomes are intracellular magnetic nanocrystals composed of magnetite (Fe3O4) or greigite (Fe3S4), enveloped by a lipid bilayer membrane, produced by magnetotactic bacteria. Because of the stability of these structures in certain environments after cell death and lysis, magnetosome magnetite crystals contribute to the magnetization of sediments as well as providing a fossil record of ancient microbial ecosystems. The persistence or changes of the chemical and magnetic features of magnetosomes under certain conditions in different environments are important factors in biotechnology and paleomagnetism. Here we evaluated the thermal stability of magnetosomes in a temperature range between 150 and 500 °C subjected …

Comatose Within 6 Weeks, But Still Alive After 3 Years, Creutzfeldt‐Jakob Disease With Unusual Progression, Julia Kathleen Christopher, Brian Khong, Amin Abolfazli, Antonio Liu

School of Medicine Faculty Research

Creutzfeldt‐Jakob disease (CJD) should still be considered in a patient presenting with rapidly progressive dementia and negative CSF 14‐3‐3 protein and RT‐QulC. Treatable causes of encephalopathy must be ruled out. Neurodegenerative diseases must also be considered.

Effects Of Acute Dietary Polyphenols And Post-Meal Physical Activity On Postprandial Metabolism In Adults With Features Of The Metabolic Syndrome, Dustin W. Davis, James W. Navalta, Graham R. Mcginnis, Reimund Serafica, Kenneth Izuora, Arpita Basu

Kinesiology and Nutrition Sciences Faculty Research

Approximately 22% of U.S. adults and 25% of adults globally have metabolic syndrome (MetS). Key features, such as dysglycemia and dyslipidemia, predict type 2 diabetes, cardiovascular disease, premature disability, and death. Acute supplementation of dietary polyphenols and post-meal physical activity hold promise in improving postprandial dysmetabolism. To our knowledge, no published review has described the effects of either intervention on postprandial glucose, insulin, lipids, and markers of oxidative damage and inflammation in adults with features of MetS. Thus, we conducted this review of controlled clinical trials that provided dietary polyphenols from oils, fruits, teas, and legumes during a dietary challenge, …

Impact Of Health Promoting Nutrition Intervention Package On Severe Malnutrition Among Under-Five Children In Rural Northern India, Poonam Khanna, Tejinder P. Singh, Rajbir Kaur, Jill Miller, Thakur Mejie, Sonia Minhas, Jyoti Dixit, Manoj Sharma

Environmental & Global Health Faculty Research

Globally, 17 million children under 5 years of age are affected with severe malnutrition. Severe wasting is a key contributor (12.6%) to child deaths due to nutritional deficiencies and is responsible for several morbid conditions. The purpose of this paper was to assess the impact of nutritional counseling intervention on severe malnutrition among rural under-five children in Northern India. Nine villages in an ongoing project were included in the study to include all the under-five children (N=573) from these villages. Nutritional assessment was performed as per World Health Organization (WHO) child growth standards. Based on their z-scores of malnourishment indicators, …

Microrna Profiling In The Weddell Seal Suggests Novel Regulatory Mechanisms Contributing To Diving Adaptation, Luca Penso-Dolfin, Wilfried Haerty, Allyson Hindle, Federica Di Palma

Life Sciences Faculty Research

Background:The Weddell Seal (Leptonychotes weddelli) represents a remarkable example of adaptation to diving among marine mammals. This species is capable of diving... (See full abstract in article).

Ensemble Modeling Of Auditory Streaming Reveals Potential Sources Of Bistability Across The Perceptual Hierarchy, David F. Little, Joel S. Snyder, Mounya Elhilali

Psychology Faculty Research

Perceptual bistability—the spontaneous, irregular fluctuation of perception between two interpretations of a stimulus—occurs when observing a large variety of ambiguous stimulus configurations. This phenomenon has the potential to serve as a tool for, among other things, understanding how function varies across individuals due to the large individual differences that manifest during perceptual bistability. Yet it remains difficult to interpret the functional processes at work, without knowing where bistability arises during perception. In this study we explore the hypothesis that bistability originates from multiple sources distributed across the perceptual hierarchy. We develop a hierarchical model of auditory processing comprised of three …

Kinematic Analyses Of Parkour Landings From As High As 2.7 Meters, Boyi Dai, Jacob S. Layer, Taylour J. Hinshaw, Ross F. Cook, Janet S. Dufek

Integrated Health Sciences Faculty Research

During landing tasks, forces and moments are generated by the musculoskeletal system at surface contact to progressively decelerate the velocity of the body (Dufek and Bates, 1990; McNitt-Gray, 1993). When landing after a forward jump, the body’s downward velocity must be decelerated by an upward acceleration, while its forward velocity needs to be decelerated by a backward acceleration. Inappropriate landing patterns can cause excessive loading to the body, resulting in musculoskeletal injuries. The anterior cruciate ligament is commonly injured by abnormal landing patterns during athletic activities (Dai et al., 2015b; Krosshaug et al., 2007). Military training also involves jump-landing tasks …

Developing Minimal-Input Techniques For Invasive Plant Management: Perimeter Treatments Enlarge Native Grass Patches, Scott R. Abella, Lindsay P. Chiquoine, Jeremy M. Moss, Eric D. Lassance, Charles D. Schelz

Hospitality Faculty Research

There is a continual need for invasive plant science to develop approaches for cost-effectively benefiting native over nonnative species in dynamic management and biophysical contexts, including within predominantly nonnative plant landscapes containing only small patches of native plants. Our objective was to test the effectiveness of a minimal-input strategy for enlarging native species patches within a nonnative plant matrix. In Pecos National Historical Park, New Mexico, USA, we identified 40 native perennial grass patches within a matrix of the nonnative annual forb kochia [Bassia scoparia (L.) A.J. Scott]. We mechanically cut B. scoparia in a 2-m-wide ring surrounding the perimeters …

Non-Native Spiders Change Assemblages Of Hawaiian Forest Fragment Kipuka Over Space And Time, Julien Pétillon, Kaїna Privet, George K. Roderick, Rosemary G. Gullespie, Don K. Price

Life Sciences Faculty Research

We assessed how assemblages of spiders were structured in small Hawaiian tropical forest fragments (Hawaiian, kipuka) within a matrix of previous lava flows, over both space (sampling kipuka of different sizes) and time (comparison with a similar study from 1998). Standardized hand-collection by night was carried out in May 2016. In total, 702 spiders were collected, representing 6 families and 25 (morpho-)species. We found that the number of individuals, but not species richness, was highly correlated with the area of sampled forest fragments, suggesting that kipuka act as separate habitat islands for these predatory arthropods. Species richness was significantly lower …

Mob Family Proteins: Regulatory Partners In Hippo And Hippo-Like Intracellular Signaling Pathways, Juan Carlos Duhart, Laurel A. Raftery

Life Sciences Faculty Research

Studies in yeast first delineated the function of Mob proteins in kinase pathways that regulate cell division and shape; in multicellular eukaryotes Mobs regulate tissue growth and morphogenesis. In animals, Mobs are adaptors in Hippo signaling, an intracellular signal-transduction pathway that restricts growth, impacting the development and homeostasis of animal organs. Central to Hippo signaling are the Nuclear Dbf2-Related (NDR) kinases, Warts and LATS1 and LATS2, in flies and mammals, respectively. A second Hippo-like signaling pathway has been uncovered in animals, which regulates cell and tissue morphogenesis. Central to this emergent pathway are the NDR kinases, Tricornered, STK38, and STK38L. …

Global Trends And Gaps In Research Related To Latent Tuberculosis Infection, Liling Chaw, Lung-Chang Chien, Justin Wong, Ken Takahashi, David Koh, Ro-Ting Lin

Environmental & Global Health Faculty Research

Background There is a global commitment to eliminating tuberculosis (TB). It is critical to detect and treat cases of latent TB infection (LTBI), the reservoir of new TB cases. Our study assesses trends in publication of LTBI-related research. Methods We used the keywords (“latent tuberculosis” OR “LTBI” OR “latent TB”) to search the Web of Science for LTBI-related articles published 1995–2018, then classified the results into three research areas: laboratory sciences, clinical research, and public health. We calculated the proportions of LTBI-related articles in each area to three areas combined, the average rates of LTBI-related to all scientific and TB-related …

Regeneration Dynamics Of Great Basin Bristlecone Pine In Southern Nevada, Philip J. Burton, Jesy Simons, Steve Brittingham, Daniel B. Thompson, Darin W. Brooks, Lawrence R. Walker

Library Faculty Research

Great Basin bristlecone pine (Pinus longaeva D.K. Bailey) is an important and long-lived tree species found at high elevations in the interior southwest of the United States, but little is known about its regeneration requirements and response to disturbance. We conducted extensive surveys of seedling regeneration and environmental attributes of regeneration sites in undisturbed forest dominated by this species in the Spring Mountains of southern Nevada. Additional surveys tallied new seedling densities and site attributes 4 years after a wildfire in the same area. Seedlings, saplings, and juvenile trees were less abundant than adult trees in the unburned forest, and …

Non-Amyloid Approaches To Disease Modification For Alzheimer’S Disease: An Eu/Us Ctad Task Force Report, Serge Gauthier, P. S. Aisen, J. Cummings, M. J. Detke, F. M. Longo, R. Raman, M. Sabbagh, L. Schneider, R. Tanzi, P. Tariot, M. Weiner, J. Touchon, B. Vellas

School of Medicine Faculty Research

© 2020, The Author(s). While amyloid-targeting therapies continue to predominate in the Alzheimer’s disease (AD) drug development pipeline, there is increasing recognition that to effectively treat the disease it may be necessary to target other mechanisms and pathways as well. In December 2019, The EU/US CTAD Task Force discussed these alternative approaches to disease modification in AD, focusing on tau-targeting therapies, neurotrophin receptor modulation, anti-microbial strategies, and the innate immune response; as well as vascular approaches, aging, and non-pharmacological approaches such as lifestyle intervention strategies, photobiomodulation and neurostimulation. The Task Force proposed a general strategy to accelerate the development of …

Step Count Reliability And Validity Of Five Wearable Technology Devices While Walking And Jogging In Both A Free Motion Setting And On A Treadmill, Jeffrey Montes, Richard Tandy, John Young, Szu-Ping Lee, James W. Navalta

Kinesiology and Nutrition Sciences Faculty Research

Wearable technology devices are used by millions of people who use daily step counts to promote healthy lifestyles. However, the accuracy of many of these devices has not been determined. The purpose was to determine reliability and validity of the Samsung Gear 2, FitBit Surge, Polar A360, Garmin Vivosmart HR+, and the Leaf Health Tracker when walking and jogging in free motion and treadmill conditions. Forty volunteers completed walking and jogging free motion and treadmill protocols of 5-minute intervals. The devices were worn simultaneously in randomized configurations. The mean of two manual steps counters was used as the criterion measure. …