Life Sciences Commons^™

An Evaluation Of Methicillin Resistant Staphylococcus Aureus Survival On Five Environmental Surfaces Under Two Different Humidities, With And Without The Addition Of Bovine Serum Albumin, Courtney Ann Coughenour

UNLV Theses, Dissertations, Professional Papers, and Capstones

The spread of antibiotic resistant bacteria is a major public health concern, as they result in greater healthcare costs and increased morbidity and mortality rates. Methicillin resistant Staphylococcus aureus (MRSA) is one organism of particular concern, with the number of infections increasing in epidemic proportion. Bacterial surface contamination with MRSA is significant, as it may serve as a reservoir for transmission and have negative health implications. The purpose of this study was to evaluate survival of MRSA on five environmental surface materials; glass, wood, vinyl, plastic, and cloth. The effect of relative humidity (RH) and bovine serum albumin (BSA) were …

Identifying Biomarkers For Resistance To Novel Cisplatin Analogues In Human Lung, Breast And Prostate Cancers, Becky Michelle Hess

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cisplatin is a common therapeutic agent used in cancer treatment. Unfortunately, resistance to cisplatin in addition to severe side effects limits its use in cancer treatment. Two novel cisplatin analogues, 4DB and 4TB were shown to have varying cytotoxicity in lung, breast and prostate cancer cells. The hypothesis for this study states that the differences in 4DB and 4TB cytotoxicity among different tissue types is due to the type and efficiency of DNA repair mechanisms involved in response to these drugs.

To test the hypothesis, proteins involved in the rate limiting step of nucleotide excision repair (NER) and mismatch repair …

Mercury Concentrations In Muscle Tissue From Sportfish In Lake Mead, Nevada, Joanna L. Kramer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lake Mead is the largest reservoir by volume in the United States and provides fishing opportunities for numerous anglers. Considerable attention has been given to the bioaccumulation of methylmercury in fish tissues, however, no formal study utilizing approved USEPA methodology has been conducted to quantify the amount of mercury present in fish tissue from Lake Mead. The purpose of this study is to determine the concentrations of mercury present in the most commonly consumed fish from Lake Mead and to identify if any of the 4 major basins contain fish with elevated concentrations of mercury. Largemouth bass (n=49), striped bass …

Water Quality Changes In A Constructed Wetland At The Springs Preserve In Las Vegas, Nevada, Aaron Mathis Miller

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Springs Preserve near downtown Las Vegas, Nevada contains a seven-acre constructed wetland. Springs Preserve managers are planning to use water from the constructed wetland to irrigate creeks immediately north of the wetland. These creeks will be used by a variety ofaquatic wildlife, including endangered amphibians sensitive to harmful metalloids, such as selenium, lead, and arsenic.

In an attempt to answer toxicological questions about contaminant concentrations in the constructed wetland, three metals and metalloids (selenium, arsenic, and lead), two nutrients (nitrogen and phosphorus), and the major ionic species were analyzed at four sampling locations for aqueous concentrations, in two separate …

Distribution And Site Selection Of Le Conte's And Crissal Thrashers In The Mojave Desert: A Multi-Model Approach, Dawn Marie Fletcher

UNLV Theses, Dissertations, Professional Papers, and Capstones

Information on the distribution and habitat requirements of a species are critical components to the development of meaningful conservation plans. Such knowledge, however, is particularly difficult to obtain for species that are elusive and occur at low densities, such as the Le Conte's ( Toxostoma lecontei ) and Crissal (Toxostoma crissale ) thrashers. In association with a regional conservation plan, I evaluated the distribution and habitat selection of these thrashers within Clark County, Nevada in the eastern Mojave Desert. I used a call-broadcast approach to sample 432 stratified random locations, detecting Le Conte's thrashers at 45 locations and Crissal …

The Role Of Larval Fat Cells In Starvation Resistance And Reproduction In Adult Drosophila Melanogaster, Jerell Roland Aguila

UNLV Theses, Dissertations, Professional Papers, and Capstones

The intricate life cycle of holometabolous insects includes well-defined larval and adult stages associated with feeding and non-feeding periods. The larval stage is distinguished by prevalent feeding and is necessary for supporting the animal as it quickly grows. The larval stage also serves as the period for the animal to obtain adequate energy stores, primarily in the larval fat body, to fuel the animal through the non-feeding pupal and immature adult stages. Acquiring sufficient energy stores is paramount for the success of the adult animal. In fact, certain insects, such as silkworms and mayflies, do not feed as adults and …

An Examination Of Body Composition Measurement Methods In Children, Robert Kaplan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction . Body-composition methods include underwater weighing (UWW), skinfold thickness (SKF), bioelectrical impedance (BIA), and the BOD POD. Although these techniques are used routinely, each has its inherent limitations, especially in children. Purpose . The purpose of this study was to examine the various methods of body composition in children. Methods . The body composition of 7 boys between the ages of 12-14 (13.1 +/- 1.1 years) was determined using the BOD POD, UWW, SKF, and BIA. Results . Percent body fat estimated from the BOD POD (21.9 +/- 7.8%BF) was not significantly different than the estimated percent fat from …

Molecular Epidemiology Of Methicillin-Resistant Staphylococcus Aureus (Mrsa), Ilene Bautista

UNLV Theses, Dissertations, Professional Papers, and Capstones

Staphylococcus aureus is a frequent cause of a myriad of infections in hospitals, healthcare facilities and community settings. It is often related to skin and soft tissue infection, but it can also cause other diseases varying from food poisoning to endocarditis and toxic shock syndrome. According to a study by Kuehnert et al. (2006) there has been a strong association between Staphylococcus aureus (S. aureus) carriage and risk factors for subsequent infections. Subsequent infection from S. aureus , including methicillin-resistant S. aureus (MRSA) infection, can be projected by looking at the presence of S. aureus nasal colonization. The purpose of …

The Effect Of Concurrent Cell Phone Use And Walking On Gait Characteristics, Jennifer Marie Aldridge

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study examined the effects that cell phone use has on gait and situation awareness. Subjects (n=18; 24.67±3.60 yrs) completed three five-minute treadmill walking conditions (self-selected speed): (1) CONTROL (walking only), (2) TALK (walking and talking), and (3) TEXT (walking and texting). The number of detected lights presented in the visual field was recorded, as were kinematic data of the feet. Using a one-way repeated measure ANOVA it was determined light detection (F _(2,17) =39.777, p<0.001) and TC_min (F_(2,17) =8.574, p=0.001) were different between conditions. Specifically, light detection decreased during TEXT (2.6±2.2 lights) versus TALK (5.8±0.05 lights, p<0.001) or CONTROL (5.9±0.05 lights, p<0.001); TC_min decreased …

Arid Climate Decomposition And Decay: A Taphonomic Study Using Swine, James William Munkres

UNLV Theses, Dissertations, Professional Papers, and Capstones

The present project analyzes the taphonomic processes and variables involved in the decomposition and desiccation of animal remains in an arid/hyper-arid environment. The study and the derived data will assist in determining postmortem intervals for remains in modern contexts, inform judgments made regarding mortuary habits and techniques in archaeological contexts, and will improve our knowledge regarding taphonomic processes. Manner of deposition, the depositional surface/medium and arid-climate specific variables (temperature, water, insect activity, weathering, pH levels, and soil characteristics) were examined in this study. Reported observations are limited to the first ten months following death from early December through early October …

The Influence Of Carbon Source Types And Nitrate On The Performance Of The Enhanced Biological Phosphorus Removal Systems, Shamim Ara Begum

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research focuses on two issues in enhanced biological phosphorus removal (EBPR). The first issue encompasses the effect of the type of carbon sources (i.e. volatile fatty acids and non volatile fatty acids) on the microbiology of EBPR. The second issue deals with the influence of denitrification on EBPR. Few studies have been performed to investigate these two issues. The recent findings on these areas are summarized below to establish the knowledge gaps this dissertation attempted to address. Details on the specific findings can be found in the literature review portion of this proposal.

Investigation Of Plant Water Use In The Great Basin, Nv, Benjamin Conrad

UNLV Theses, Dissertations, Professional Papers, and Capstones

Global climate change in addition to a growing population can have a strong impact on our natural resources. In particular, cities in the semi-arid and arid southwestern US are currently faced with the challenge of providing sustainable fresh water to a growing population. In Las Vegas, dwindling water levels in Lake Mead have forced water managers to seek water resources from Spring Valley and Snake Valley, NV, which are located 402 km north of the city. The goals of this research were to investigate the water use of shrubs located in these valleys by using a large aperture scintillometer (LAS) …

Identification Of Arid Soil Inducible Genes In Pseudomonas Fluorescens Strain Pf0-1, Katila Pipitone

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis contains three major sections: introduction, literature review and the project entitled: 'Identification of Arid Soil Inducible Genes in Pseudomonas fluorescens Strain Pf0-1'. The introduction section describes a general background, the current and potential applications of P. fluorescens and the main goal of this dissertation. The literature review chapter discusses two main areas. The first area offers insights about different types of in vivo expression technology (IVET) as a tool in gene identification. This section also describes the limitations of IVET, as well as the benefits over other methods for gene identification. The second part of the literature review …

System Architecture For An Intelligent Implantable Bio-Telemetry Device, Karthik Kumar Nattamai Kumaresan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biotelemetry has long been used for environmental and life science research to study animal populations and behavior. The use of implantable bio-telemetric techniques makes it possible to record and study physiological variables during long-term experiments with a minimum disturbance to the animal. Fully implantable telemetric techniques greatly reduce the risk of infection associated with leads and catheters protruding from the skin. In this research the design and implementation of a completely programmable bio-implantable digital system which can measure two physiological signals extended over a period of time is considered. The proposed system consists of a standalone implantable transmitter unit and …

Protection Of Macrophages J774a.1 By Purine Nucleoside Analogues From Bacillus Anthracis Mediated Necrosis, Zadkiel R. Alvarez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Eight years after the lamentable anthrax attacks, major scientific effort continues to be done, in order to stop imminent acts of bioterrorism. Innovative ways of therapy against the anthrax disease are being investigated. B. anthracis, the etiological agent of the infection, has a dormant stage in its life cycle known as the endospore. When conditions become favorable spores germinate, transforming into vegetative bacteria. In inhalational anthrax, the most fatal manifestation of the disease, spores enter the organism through the respiratory track, and are phagocytosized by alveolar macrophages of the lungs. Spores are able to sense nutrient availability, activating their germination …

Experimental And Natural Variation In Hovering Flight Capacity In Bees, Hymenoptera: Apidae, Jason Thomas Vance

UNLV Theses, Dissertations, Professional Papers, and Capstones

In honey bees, the capacity for flight underlies many behaviors which impact fitness and longevity, such as the ability to forage or evade predators. However, flight capacity is not fixed across bees' lifespan, which is punctuated by a suite of physiological changes that accompany age and the transition from in-hive to foraging behaviors; thus, flight capacity may vary during periods of development, senescence, or in response to morphological damage such as wing wear. This dissertation describes the biomechanics and aerodynamics which contribute to the scope of honey bee flight performance, and investigates how age, behavioral development, and wing-wear affects flight …

Characterization Of Aerobic Respiration In Great Basin Hot Springs, Caitlin N. Murphy

UNLV Theses, Dissertations, Professional Papers, and Capstones

Despite a wide diversity of possible electron donors available to fuel chemolithotrophy, it has been proposed that hydrogen is the single most important electron donor in geothermal ecosystems. To directly test this hypothesis, a simple system was devised to determine whether microorganisms in hot spring water and sediment are capable of using hydrogen and other electron donors for aerobic respiration using microrespirometry. The protocol for these experiments was developed using pure cultures of Thermocrinis ruber to determine the effect of growth conditions on the rate of oxygen consumption following the addition of electron donors. For field experiments, samples were collected …

Ground Reaction Forces For Children Running In Different Shoes, Dana Forrest

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to determine whether certain ground reaction force parameters such as impact force (F1), second maximum force (F2), loading rate, stance time and average vertical ground reaction force (Fzavg) differ when 11-13 year old children run in a neutral shoe (Nike Air Pegasus+ 25) that is either a child or adult style.

Shoes were impact tested in an impact test instrument to determine any performance differences between the two shoes. Next, 10 healthy female subjects aged 12.03 ± 1.14 years with a height of 154.6 ± 4.90 cm and a mass of 46.18 ± 14.33 …

When Did The Ancestors Of Polynesia Begin To Migrate To Polynesia? The Mtdna Evidence, David Lesniewski

UNLV Theses, Dissertations, Professional Papers, and Capstones

The timing and nature of the migration of the ancestors of the Polynesian people is debated by two competing theories. The "Express Train" and "Slow Boat" theories assert that the migration of the Proto-Polynesian people began around 6,000 years before present (BP) or around 10,000 years BP respectively. Through the use of haplogroups and specific genetic mutations a direct relationship between the Proto-Polynesians and modern Polynesians was attempted to test which of these theories was correct. The ancient skeletal remains from the island of Borneo currently housed at UNLV were used in this study as their dates fall within both …

Neurocognitive Deficits And Functional Outcome In Bipolar Disorder, Danielle T. Bello

UNLV Theses, Dissertations, Professional Papers, and Capstones

Bipolar disorder affects approximately 1% of the population. It is a severe and debilitating illness, causing serious impairment of interpersonal, occupational and social functioning. The disorder is characterized by marked mood swings as well significant neurocognitive deficits. Based on work with other psychiatric and neurological disorders, neurocognitive deficits in bipolar disorder are expected to be strong predictors of functional capacity. However, few studies have evaluated the consequences of neurocognitive deficits in this disorder. Most available studies have focused on the clinical correlates of functional outcome, such as number of hospitalizations, age of disorder onset, and severity of symptoms. While useful, …

Integrated Responses Of Crustaceans Inhabiting Estuaries To The Challenges Of Feeding And Digestion In Low Salinity, Daniel Luke Curtis

UNLV Theses, Dissertations, Professional Papers, and Capstones

Estuaries are highly productive and serve as vital habitats for numerous decapod crustacean species. However, the environmental conditions within estuaries are often highly dynamic and subject to large changes in salinity and temperature that occur on seasonal and tidal scales. Not all of the species occupying these habitats are adept in coping with changes in these environmental conditions. This dissertation describes the influence of low salinity conditions on the 1) habitat preference, 2) feeding behaviour and 3) digestive physiology of crustaceans inhabiting estuaries. I have primarily focussed on a weak osmoregulator, the Dungeness crab, Cancer magister , but have also …

Effects Of Plant Uptake And Micro-Topography On Chloride Transport In Arid Soils, Wenming Nie

UNLV Theses, Dissertations, Professional Papers, and Capstones

Chloride concentration profiles to depths of 1 m were evaluated on a young alluvial fan in Eldorado Valley, NV. It was found that chloride beneath plant canopies were 11 to 222 times higher than adjacent (1 - 2 m away) bare soil locations. Two-dimensional numerical simulations using HYDRUS 2D/3D model were used to further explore the impact of plants on chloride transport. The simulation results indicated that lateral flow driven by root uptake concentrated chloride toward root zones, leading to the accumulation of chloride under plant canopies. Results also suggest that locally micro-topography can have a substantial impact on chloride …

Molecular Systematics And Phylogeography Of The Genus Richardsonius, Derek Dee Houston

UNLV Theses, Dissertations, Professional Papers, and Capstones

The complex geological and climatic events that significantly altered the landscape throughout the Cenozoic Era impacted the diversification of many North American taxa, including freshwater fishes. Here, I employ an array of phylogenetic analyses using a multiple gene tree approach to address several questions regarding the phylogenetic relationships of the North American cyprinid genus Richardsonius and two other closely related genera, Clinostomus and Iotichthys. I also use divergence time estimates generated using fossil calibrations to qualitatively assess the phylogeographic implications of evolution within and among these three genera. Mitochondrial and nuclear DNA sequences show a sister relationship between Iotichthys and …