Life Sciences Commons^™

Co-Development Of Biological Soil Crusts, Soil-Geomorphology, And Landscape Biogeochemistry In The Mojave Desert, Nevada, U.S.A. – Implications For Ecological Management, Amanda Jean Williams

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biological soil crusts (BSCs) are complex matrices of soil particles, mosses, lichens, and cyanobacteria that prevent erosion and influence water and energy balances, soil fertility, and vascular plant germination. The processes that form BSCs, the factors that control their distribution, and the ecosystem feedbacks that they sustain are poorly understood. This dissertation employed a novel interdisciplinary approach to address those research unknowns through investigations of the micromorphological structure, soil-geomorphic relationships, and biogeochemical feedbacks of BSCs in the Mojave Desert.

A micromorphological study of BSCs resulted in a succession model that illustrates how crust formative processes and structures change through time. …

Agonist And Stabilizer Muscle Activity During A Push Up On Unstable Surfaces, Anthony J. Dyrek

UNLV Theses, Dissertations, Professional Papers, and Capstones

A recent trend among fitness professionals is to have clients perform resistance exercises on unstable equipment. Anecdotally, this is done with the intent that stabilizing and agonist muscles are more active while doing certain exercises on unstable surfaces. However, there are limited data as to whether or not this is the case and no studies have investigated muscle activity while doing the same exercise on surfaces that offer different levels of stability. Therefore, the purpose of this study is to measure electromyography (EMG) during push up exercise performed on unstable surfaces as well as on the ground. Surface EMG was …

Effect Of Aquastretch On Range Of Motion At Knee Joint In Total Knee Arthroplasty Patients, Raja Devinder Kochar

UNLV Theses, Dissertations, Professional Papers, and Capstones

The success of the Total Knee Arthroplasty (TKA) depends upon its functional outcomes of increase in reduction in pain, and gait ambulation and performing functional activities of daily living. Compromised range of motion, pain and weakness can reduce their ability to perform activities of daily living. Aquatic Physical Therapy may offer an alternative intervention to traditional Physical Therapy Rehabilitation and many studies have shown improvements in range of motion, swelling, pain reduction, stiffness and quality of life after TKA. AquaStretch, a relatively new form of aquatic therapy, claims to restore the functional mobility which is lost restrictions caused due to …

Analysis Of Morris Water Maze Data With Bayesian Statistical Methods, Maxym V. Myroshnychenko, Anton Westveld, Jefferson Kinney

Festival of Communities: UG Symposium (Posters)

Neuroscientists commonly use a Morris Water Maze to assess learning in rodents. In his kind of a maze, the subjects learn to swim toward a platform hidden in opaque water as they orient themselves according to the cues on the walls. This protocol presents a challenge to statistical analysis, because an artificial cut-off must be set for those experimental subjects that do not reach the platform so as they do not drown from exhaustion. This fact leads to the data being right censored. In our experimental data, which compares learning in rodents that have chemically induced symptoms of schizophrenia to …

Sustainable Alternative To Non-Biological Nitrogen Fixation To Nitrate For Fertilizers, Patrick Freeze, Glenn Miller

Festival of Communities: UG Symposium (Posters)

Currently, the industrial method of nitrogen fixation for use in fertilizers (Haber- Bosch process [N2 (g) + 3 H2 (g) <--> 2 NH3 (g)]) is our main source of non-biological conversion of atmospheric nitrogen to ammonia. The proposed research experiment utilizes the catalytic mechanism of titanium dioxide which, in the presence of heat or sunlight, undergoes fixation of atmospheric nitrogen. This method of nitrate production could serve as a sustainable source of nitrogen for fertilizers. Variables in the experiment included the manipulation of thermal pressure, heat, and base addition to counteract hydrochloric acid production, a selflimiting byproduct.

Accumulation Of Polonium-210 In Different Species Of Fish In Lake Mead, Suraj Ghevarghese John, Shungmugam Nallaperumal, Vernon Hodge

Festival of Communities: UG Symposium (Posters)

Discovered by Pierre Curie and Marie Skłodowska-Curie in 1898, polonium is a chemical element with an atomic number of 84. This rare naturally occurring radioactive element is chemically similar to bismuth and tellurium, and forms in uranium ores. Polonium-210 is an naturally occurring radioactive element with a half-life of 138.376 days(1). This element is found in trace amounts in most organisms. Our research is focused on the accumulation of polonium-210 in fish that occupy in Lake Mead.

The sample species is chosen based on varying lake stratification (layers of the lake). This gives us a good idea of the difference …

The Effects Of Climate Change On Basic Animal Cell Functions, Michelle Fulbright, Andrew Andres

Festival of Communities: UG Symposium (Posters)

Increasing global temperatures during the 21st century may have detrimental effects on basic cell functions within ectothermal animals. This project aims to systematically examine the effects of climate change on secretory cargo localization through the analysis of Rab Proteins found in the model organism Drosophila melanogaster. Rab Proteins play an essential role in vesicular transport within the cell and can be genetically manipulated to monitor the biological consequences of global warming.

Exploring The Potential Of Agave As A Biofuel Crop On Arid Land, Rhea Conlu, Diana Ha, Jeffery Shen

Festival of Communities: UG Symposium (Posters)

Worldwide awareness of global warming and depleting fossil fuel sources has made research into alternative resources, such as plant fuels imperative. Since groundwater irrigation is unsustainable, especially in desert climates, plants that are drought resistant or can utilize otherwise unusable water are more viable sources of future biofuel production. Agave nevadensis, a species belonging to the family Agavaceae are succulent plants native to Las Vegas. This experiment aims to expose A. nevadensis to both wastewater and drought conditions and observe its response. The results can help define Agave as a water-resourceful biofuel both tolerant of drought and capable of utilizing …

Oral Presentation: Plant Genes And Drought Tolerance, Norris Lam

Festival of Communities: UG Symposium (Posters)

Research has shown that a gene from C3 xerophyte Larrea tridentata (creosote bush), LtWRKY21, is involved in pathways governing creosote bush’s high tolerance to environmental stress. By understanding the way in which creosote bush adapts to drought, crop plants can be engineered to be more drought tolerant during times of imminent global climate change. To study the underlying mechanisms of creosote bush drought response, the LtWRKY21 gene was mobilized into the model organism Arabidopsis thaliana. Chlorophyll degradation, cellular electrolyte leakage, and water content in leaves will serve as indicators of drought tolerance in LtWRKY21-transgenic A. thaliana after treatment in chemically …

Construction And Use Of A Direct Calorimeter To Estimate Energy Expenditure In Hibernators, Mark S. Burger, Frank Van Breukelen

Festival of Communities: UG Symposium (Posters)

Metabolic rates have traditionally been estimated through indirect calorimetry (gas exchange or respirometry) due to its ease and availability. Oxygen consumption neglects the contributions of anaerobic metabolism, while direct calorimetry (heat production) estimates both anaerobic and aerobic metabolism. Walsberg and Hoffman (2005) report anaerobic metabolism may be more important to small rodents than was previously thought. During the non-steady state of mammalian hibernation, we hypothesize that anaerobic processes may play an even greater role in fueling metabolism. To address this question, we constructed a very sensitive calorimeter that utilizes the Seebeck effect from a thermoelectric element (Peltier device). We describe …

Has Recent Climate Change Caused A Genetic Bottleneck In A Sierra Nevada Population Of The Bushy-Tailed Woodrat?, Mitchell Gritts, Angela D. Hornsby, Majorie D. Matocq

Festival of Communities: UG Symposium (Posters)

Many montane species respond to climate change by shifting their range upslope as temperatures at lower elevations increase. An elevation range shift causes a range contraction that may result in a population bottleneck. Joseph Grinnell surveyed the fauna along the Yosemite transect from 1914 to 1920. In 2003 Craig Moritz and his colleagues began to resurvey the Yosemite transect to assess the faunal change during a century of climate change. The bushy-tailed woodrat suffered severe range contraction and population bottleneck between the two surveys. I will use evolutionary models to determine if the population has suffered a genetic bottleneck.

The Release Of Calcium In Bacillus Anthracis Pathogenicity Methods, Natiera Magnuson, Manomita Patra Bhowmik, Maria Elena Reynaga, Ernesto Abel-Santos

Festival of Communities: UG Symposium (Posters)

Anthrax infection starts with germination of Bacillus anthracis spores in macrophages. Some bacteria, including B. anthracis, can sporulate in response to environmental stress, such as starvation. During germination, large concentrations of calcium ions are released from the B. anthracis spore. Calcium ions are hydrophilic secondary messengers, and may therefore interfere with detection of the spore by confusing the cell signaling pathways. We investigated calcium release on infected macrophage viability by replacing the calcium stored in B. anthracis spores for other cations via demineralization/remineralization. It was discovered that calcium ions typically out-performed other cations in germination of B. anthracis.

Characterization Of Ips Pini Ipsdienol Dehydrogenase (Idol Dh), Heidi Pak, Claus Tittiger, William Welch

Festival of Communities: UG Symposium (Posters)

Ipsdienol is an important pheromone component for pine engraver beetle, Ips pini. Ipsdienol is a ten carbon monoterpenoid secondary alcohol and ipsdienone is the corresponding ketone. We are characterizing the activity of recombinant IDOL DH produced in Sf9 (insect) cells. The enzyme has a high stereospecificity: (-) ipsdienol was found to be a substrate while (+)-ipsdienol was neither a substrate nor inhibitor. Closely related monoterpenoids, such as nerol, geraniol, and citral, were neither substrates nor inhibitors. Smaller compounds, such as 2-propanol, also failed to act as an inhibitor or substrate. This indicates the binding site of this enzyme is highly …

Does Thermal Stress Cause Females Of The Plant Bryum Argenteum To Manipulate The Sex Ratios Of Their Offspring?, Elisha Rhodes, Lloyd Stark

Festival of Communities: UG Symposium (Posters)

About half of all moss taxa exhibit female-biased sex ratios, and bryophyte male rarity remains largely unexplained. One possible explanation is differential stress tolerance of spores due to maternal sporophyte manipulation during stress. To test this hypothesis, sporophytes of the species Bryum argenteum were subjected to thermal stress and observed for growth abnormalities and sporophyte abortions. Data display a correlation between increased temperature and increased sporophyte abortions as well as increased time to complete meiosis, possibly indicating decreased fitness. Continued global warming may create more stressful environments for sporophytes resulting in the elimination of males from local populations.

Effect Of Temperature And Oxygen Levels On Lactate Production In Palaemonetes Pugio, Robin Schofield, Teresa Mika, Carl Reiber

Festival of Communities: UG Symposium (Posters)

Oxygen delivery rates must keep pace with the increased metabolic rate observed in poikilothermic animals exposed to increased temperature if aerobic metabolism is to be maintained. Physical failure of the oxygen delivery system to meet these demands may be a mechanism of cardiac failure in crustaceans at temperature extremes. As part of the determination of the effect of temperature on the cardio-respiratory system, we are measuring whole animal lactate levels in grass shrimp acclimated to 20°C over temperature ranges in normoxic and hyperoxic conditions. Lactate levels are measured as an indicator of a switch from aerobic to anaerobic metabolism. Animals …

Stationary Phase Mutagenesis In Bacillus Subtilisis Independent Of Genome Replication, Mark Upchurch, Holly Martin, Eduardo Robleto

Festival of Communities: UG Symposium (Posters)

Stationary phase mutagenesis is defined as cellular mechanisms that produce genetic diversity in cells experiencing conditions of stress. These processes are associated with many biological phenomena, including those that produce the formation of cancers in animal cells and other degenerative diseases. Also, these mechanisms are associated with the accumulation of beneficial mutations in bacteria, but follow stochastic processes and are controlled by genetic factors. The current models explaining the generation of stress-induced mutations are predicated on the formation of DNA replication intermediates that are formed during the repair of damaged DNA or during DNA replication and transcription encounters. Here we …

Event Program, Carl Reiber, Nicholle Booker

Festival of Communities: UG Symposium (Posters)

UNLV Undergraduates from all departments, programs and colleges participated in a campus-wide symposium on April 16, 2011. Undergraduate posters from all disciplines and also oral presentations of research activities, readings and other creative endeavors were exhibited throughout the festival.

Mojave Applied Ecology Notes Spring 2011, Scott R. Abella, Ross Guida, S. D. Smith, Christopher L. Roberts, Haroon Stephen, William J. Smith, Zhongwei Liu, James S. Holland, Aurore Giguet

Mojave Applied Ecology Notes

Red brome distribution in the eastern Mojave Desert, A look at the UNLV xeric gardens and Marjorie Barrick museum, Summary of recent science synthesis efforts

Lake Mead National Recreation Area Monitoring And Evaluation Of Sensitive Wildlife: Final Project Report, Margaret N. Rees, Jef R. Jaeger Ph.D.

Wildlife Monitoring

This task agreement was originally awarded by the National Park Service (NPS), Lake Mead National Recreation Area (LMNRA) to the Public Lands Institute at the University of Nevada, Las Vegas on September 30, 2006, and was amended to run through March 31, 2011. This agreement covered several project elements focused on:

• Monitoring and conservation actions for the relict leopard frog
• Coordinating and conducting annual bald eagle counts on Lakes Mead and Mohave
• Development and assessment of a habitat map for wintering bald eagles based on observations data collected during winter counts

• Monitoring of breeding peregrine falcons and assessment of reproductive …

Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending March 30, 2011, Margaret N. Rees

Limnological Studies

Project 1

• Technical assistance with the implementation of the Interagency Monitoring Action Plan (I-MAP) for Quagga Mussels is ongoing. During this quarter, analysis was completed for 13 juvenile/adult samples and analyses of the remaining samples are underway.
• Both research projects are well underway with 14 sample sets collected for Veliger abundance and settlement at different depths of Lake Mead and 12 samples collected for Growth of adult quagga mussels within Las Vegas Wash/Las Vegas Bay.

Project 2

• Annual summary sheets are under development for the topics listed within the Limnological and Aquatic Resource Monitoring and Research Plan for Lakes Mead …

Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending January 31, 2011, Margaret N. Rees

Limnological Studies

Project 1

• Technical assistance with the implementation of the Interagency Monitoring Action Plan (I-MAP) for Quagga Mussels is ongoing. During this quarter, analysis was completed for 21 adult/juvenile samples and analyses of the remaining samples are underway. A manuscript describing the I-MAP and its history, current recommended monitoring, and recommended future monitoring and a separate manuscript describing the I-MAP’s monitoring protocol were accepted for publication in the journal Aquatic Invasions. Two other manuscripts describing other aspects of the I-MAP program were published in Lake and Reservoir Management.

Project 2

• Annual summary sheets are under development for the topics listed within …

Scireader Enables Reading Of Medical Content With Instantaneous Definitions, Patrick R. Gradie, Megan Litster, Rinu Thomas, Jay Vyas, Martin Schiller

Life Sciences Faculty Research

Background

A major problem patients encounter when reading about health related issues is document interpretation, which limits reading comprehension and therefore negatively impacts health care. Currently, searching for medical definitions from an external source is time consuming, distracting, and negatively impacts reading comprehension and memory of the material.

Methods

SciReader was built as a Java application with a Flex-based front-end client. The dictionary used bySciReader was built by consolidating data from several sources and generating new definitions with a standardized syntax. The application was evaluated by measuring the percentage of words defined in different documents. A survey was used …

Walking Box Ranch Planning And Design Quarterly Progress Report: Period Ending January 10, 2011, Margaret N. Rees

Walking Box Ranch

• UNLV participated in three project workshops and one additional meeting to assist in planning and design of the future WBR museum and field/research station.
• Weather station progress included design of programming software that will provide past weather information to website user, two abstracts have been submitted to an energy sustainability meeting, and a paper reviewing energy efficient building envelope components has been prepared and submitted for publication.
• Work has begun on a new education project titled “Multimedia Field Guides for Public Engagement at Walking Box Ranch, Mojave Desert.” The project will develop and disseminate a modern geological and environmental field …

Environmental Factors Affecting Settlement Of Quagga Mussel (Dreissena Rostriformis Bugensis) Veligers In Lake Mead, Nevada-Arizona, Usa, Dong Chen, Shawn Gerstenberger, Sara Ann Mueting, Wai Hing Wong

Environmental & Global Health Faculty Research

Environmental factors that can affect the settlement rate of quagga mussel veligers include flow velocity, water temperature, pH, dissolved oxygen (DO), conductivity, total organic carbon (TOC), and the surface roughness of monitoring substrates. In the present study, six artificial substrates, Acrylonitrile Butadiene Styrene (ABS) plastic, High Density Polyethylene (HDPE) plastic, Concrete Underlayment Board (CUB), aluminum, stainless steel and fiberglass, were used to monitor the settlement of quagga mussel veligers at different water depths in Lake Mead, Nevada-Arizona, USA. Considering the hierarchical data structure of observed mussel densities, we investigated the relationship between mussel settlement on monitoring substrates and the surrounding …

Quagga Mussels In The Western United States: Monitoring And Management, Wai Hing Wong, Shawn Gerstenberger

Environmental & Global Health Faculty Research

Dreissenid mussels including zebra mussel (Dreissena polymorpha Pallas, 1771), originating from the Ponto-Caspian area, and quagga mussel (Dreissena rostriformis bugensis Andrusov, 1897), originating from the mouths of the Rivers Southern Bug and Dnieper are both species native to Eastern Europe, which were accidently introduced into the Laurentian Great Lakes in North America in the 1980s in ballast water (Carlton 2008; Van der Velde et al 2010). Dreissenid mussels have created severe ecological, recreational and economic impacts on many systems because they are biofoulers and efficient ecological engineers that filter large quantities of water. Examples of these wide-ranging impacts are discussed …

Mojave Applied Ecology Notes Winter 2011, Scott R. Abella, Alice C. Newton, Kenneth Chittick, Pam Sinanian

Mojave Applied Ecology Notes

Lake Mead’s collaborative applied science research program; “annoying the elephant” - ruminations on active management by Alice Newton, Lake Mead NRA vegetation manager; 2012 NWRA Lake Mead symposium sneak peak; assessing forest change using dendrochronology in the Spring Mountains.

Role Of Hydrodynamic Behavior Of Dna Molecules In Dielectrophoretic Polarization Under The Action Of An Electric Field, Hui Zhao

Mechanical Engineering Faculty Research

A continuum model is developed to predict the dielectrophoretic polarizability of coiled DNA molecules under the action of an alternating current electric field. The model approximates the coiled DNA molecule as a charged porous spherical particle. The model explains the discrepancies among scaling laws of polarizability of different-sized DNA molecules with contour length and such discrepancies are attributed to different hydrodynamic behavior. With zero or one fitting parameter, theoretical predictions are in good agreement with various experimental data, even though in experiments there are some uncertainties in regard to certain parameters.

A Phylogeographic And Population Genetic Analysis Of A Widespread, Sedentary North American Bird: The Hairy Woodpecker (Picoides Villosus), John Klicka, Garth M. Spellman, Kevin Winker, Vivien Chua, Brian T. Smith

Ornithology Program (HRC)

The Hairy Woodpecker (Picoides villosus) has one of the broadest breeding distributions of any North American bird and is also one of the most morphologically variable with as many as 21 described subspecies. This wide distribution and high degree of phenotypic diversity suggests the presence of underlying genetic structure. We used ND2 sequence from 296 individuals from 89 localities throughout the Hairy Woodpecker distribution to address this question and to explore this species’ evolutionary history. Phylogenetic analyses identified three main Hairy Woodpecker clades, each ~1.5% divergent from one another. One clade was comprised of birds from boreal and eastern zones …

2011-2012 Unlv Mcnair Journal, Cyndy Anang, Sajar Camara, Pamela Cornejo, Carla Antonieta Farcello, Ilse Anahi Garcia, Natiera Magnuson, William L. Mccurdy, Lorena Munoz, Maxym V. Myroshnychenko, Ricardo Rios, Theodore Waldeck, Barbara Wallen, Ana Zuniga, Brenda M. Aguilar, Tiffany Alexandra Alvarez, Daniel N. Erosa, Paige C. Espinosa, Carla Antonieta Farcello, Julienne Jochel Paraiso, Nathaniel Derek Phillipps, Carmen Vallin, Jacent N. Wamala, Ernesto Zamora-Ramos

McNair Journal

Journal articles based on research conducted by undergraduate students in the McNair Scholars Program

Table of Contents

Biography of Dr. Ronald E. McNair

Statements:

Dr. Neal J. Smatresk, UNLV President

Dr. Juanita P. Fain, Vice President of Student Affairs

Dr. William W. Sullivan, Associate Vice President for Retention and Outreach

Mr. Keith Rogers, Deputy Executive Director of the Center for Academic Enrichment and Outreach

McNair Scholars Institute Staff

Settlement And Growth Of Quagga Mussels (Dreissenia Rostriformis Bugensis Andrusov, 1897) In Lake Mead, Nevada-Arizona, Usa, Wai Hing Wong, Shawn Gerstenberger, Wen Baldwin, Bryan Moore

Environmental & Global Health Faculty Research

Settlement and growth of quagga mussels Dreissena rostriformis bugensis were monitored in Lake Mead, NV, USA, where the first dreissenid occurrence was confirmed in the western United States. To measure the settlement rate of these invasive mussels, seven acrylonitrile butadiene styrene (ABS) pipes were attached to a line in shallow water (7.7 m below the surface) since November 23, 2007; eight ABS pipes were placed on another line in deep water (13.4 m below the surface) since January 3, 2008. Quagga mussels were sampled from these pipes on March 19, May 21, July 9, October 20, and December 19, 2008. …