Life Sciences Commons^™

The Evolution Of Cave Mapping And Cartography, Pat Kambesis

Mammoth Cave Research Symposia

“Does it go?” Is the initial question that has inspired many a cave explorer to push the extent of a cave system. But the answer only brings more questions…how far, how long, how deep does it go? During the exploration process, as a cave system reveals its complexity, the questions also change – what is the cave’s relationship to the surface, and to surrounding caves? What are the features and obstacles that the cave contains? Those involved in cave exploration know that the only way to answer these questions is with systematic documentation in the form of cave and surface …

Mammoth Cave National Park's Max Kaemper Centennial Symposium & 9th Science Symposium: Cultural History And Research, Shannon Trimboli , Editor

Mammoth Cave Research Symposia

No abstract provided.

Woody Biomass Energy Solutions, Scott Bell

UNLV Renewable Energy Symposium

The 2008 UNLV Renewable Energy Symposium was presented by the Office of Strategic Energy Programs and co-sponsored by the Division of Research and Graduate Studies on August 20, 2008 on the UNLV campus.

The event focused on renewable energy production in Nevada, the US Southwest, and renewable research projects nationwide. It was a great opportunity for anyone working on renewable projects to collaborate with others in this field and exchange information. Over 230 individuals attended the event this year.

The Regulation Of The Icsp Promoter Of Shigella Flexneri By The Virulence Factor Virb, Maria Castellanos, Dustin Harrison, Helen Wing

Undergraduate Research Opportunities Program (UROP)

Shigella flexneri is a pathogenic bacterium that causes severe dysentery in humans commonly known as shigellosis. Shigella encodes an outer membrane protease called IcsP. The regulation of icsP expression is under direct control of a transcriptional factor called VirB, which controls the expression of many virulence genes in Shigella. Previous work has shown through deletion analysis of the icsP promoter region that sequences as far as 1368 base pairs upstream of the transcription starting site are important for the regulation of the icsP gene by VirB. However, it is still unclear whether VirB activation requires sequences within the icsP promoter …

Microbial Nitrogen Cycling In Nevada Geothermal Springs, Mitchell G. Chaires, Jeremy A. Dodsworth, Brian P. Hedlund

Undergraduate Research Opportunities Program (UROP)

Hot spring habitats above maximum photosynthetic temperature (73 ºC) are not well understood with respect to nitrogen (N) cycling. Few predictions have been made, and even fewer measurements of in situ activities have been reported. Thermodynamic calculations based on in situ chemical and temperature measurements will be used to predict the occurrence of the specific N-cycling reactions. In addition, these measurements in two springs will aid in an attempt to cultivate ammonia oxidizing species.

Gender Variation In The Prezygotic Reproductive Effort Of The Common Silver Moss, Kimberley Horsley, Lloyd Stark

Undergraduate Research Opportunities Program (UROP)

The bryophyte Bryum argenteum is a vigorous moss with a cosmopolitan distribution and high tolerance to desiccation and temperature stress. Due to its widespread nature, B. argenteum has been highly investigated (e.g., Chopra and Bhatla 1981). However, very little research has been done on the reproductive aspects of this moss with respect to gender differences. This project will address the prefertilization reproductive efforts of the moss, and look for any differences in the rate of growth and sexual expression between the sexes. The hypothesis to be tested is that males actually have a higher prefertilization reproductive effort than females and …

Construction Of A Thif Genetic Disruption In Bacillus Subtilis, Kathleen Bradley, Christine Pybus, Ronald Yasbin, Eduardo Robleto

Undergraduate Research Opportunities Program (UROP)

The goal of our research is to determine whether the level of transcription of a gene is correlated with the level of mutation in that gene. One factor involved in the mutability of a transcribed gene is the ability of the single stranded DNA to form secondary stem loop structures (SLS), in the wake of the transcription bubble, that contain unpaired mutable bases. We are interested in correlating the levels of mutation with transcription in the thiF gene, which is predicted by bioinformatic analysis to be highly mutable. To achieve this goal, Kathleen will first construct a non-polar thiF genetic …

Aerobic Respiration By Two Sulfate Reducing Magnetotactic Bacteria, Strains Rs-1 And Fh-1, Paul Howse, Sabrina Schubbe, Dennis A. Bazylinski

Undergraduate Research Opportunities Program (UROP)

Magnetotactic bacteria is the categorical name for a group of prokaryotes that biomineralize magnetosomes which are intracellular, membrane-bounded magnetic iron mineral crystals. The focus of this study is on two magnetiteproducing, magnetotactic sulfate-reducing bacteria (SRB), Desulfovibrio magneticus strain RS-1 and strain FH-1 which also belongs in the genus Desulfovibrio in the δ-Proteobacteria. SRB utilize sulfate as a terminal electron acceptor under anaerobic conditions reducing sulfate to sulfide. A large number of organic compounds as well as some inorganic compounds have been shown to provide electrons for sulfate reduction. Traditionally, because no SRB have been shown to convincingly grow with O2 …

Characterization Of The Omptin Protease, Ompt, In Escherichia Coli, Amanda Yates, Eun-Hae Kim, Helen Wing

Undergraduate Research Opportunities Program (UROP)

Omptins are outer membrane proteases found in gram negative bacteria that cause diseases in humans, such as pathogenic Escherichia coli, Shigella flexneri, Salmonella typhimurium, and Yersinia pestis. Bacterial species that express omptins cause diseases such as highly fatal plague and severe diarrhea and dysentery. The genes that encode these proteases are ompT, icsP, pgtE, and pla, respectively. These proteases are highly related in structure and share approximately 50% sequence identity. In S. flexneri, IcsP has been shown to cleave a key virulence determinant, IcsA (Egile et al., 1997). IcsA recruits host actin and allows for intracellular movement within host cells …

Assessment Of Coliform Bacteria From Point And Nonpoint Sources In The Las Vegas Wash, Susan O'Neill, Kumud Acharya

Undergraduate Research Opportunities Program (UROP)

This project focuses on an assessment of coliform bacteria from point and non point sources in Las Vegas Wash. Correlations between land use related runoffs, nutrients and organic matter loading and total coliform will be studied. Data will be collected for both daily low and high flow events. Sampling locations will cover all major land use types such as golf course, hotels, hospitals, residential areas, etc., at both the main Wash and its tributaries.

The Effects Of Host Physiological Conditions On The Expression Of Icsp In Shigella Flexneri, Karen Levy, Helen Wing

Undergraduate Research Opportunities Program (UROP)

Shigella flexneri is a gram-negative bacterium capable of causing diarrhea and dysentery known as shigellosis. It is estimated there are 167.4 million shigellosis episodes throughout the world each year causing 1.1 million deaths. Shigella invades cells in the lower intestine through an induced phagocytosis. Once in the cytoplasm, bacteria move from one cell to another using actin-based motility. The Shigella outer membrane protease IcsP regulates actin-based motility and cell-to-cell spread by cleaving the actin assembly protein IcsA from the bacterial cell surface. We hypothesize that IcsP may serve additional functions during infection. By examining which environmental signals trigger icsP expression, …

Investigation Of Gene And Protein Expression Based On Honey Bee (Apis Mellifera) Aging, Flight Experience, And Behavior, Azucena A. Benito, G. E. Mancinelli, A. Ammons, Michelle M. Elekonich

Undergraduate Research Opportunities Program (UROP)

Honeybees undergo a process of adult behavioral development, spending their first 2-3 weeks working inside the constant environment of the hive. At about 3 weeks of age workers leave the hive as foragers who gather pollen and nectar. Previous research found that bees show an enormous decline in immunity as a result of their transition from regular hive jobs to more difficult foraging activities. Foragers can be forced to go back into hive-tasks, thus becoming “reverted nurses” which may also allow a reversal of immunosenescence. Understanding how this happens could prove to be useful because if there is flexibility in …

The Effect Of Cody On Stationary Phase Mutagenesis In Bacillus Subtilis, May Yared, Holly Martin, Eduardo A. Robleto, Ronald E. Yasbin

Undergraduate Research Opportunities Program (UROP)

We examine the notion that cells in conditions of stress accumulate mutation is in genes under selection via transcription processes. CodY is a global transcriptional regulator in many Gram positives, including soil and pathogenic microbes. In conditions of exponential growth and when branch chain amino acids and GTP are in abundance CodY acts as a transcriptional repressor of many metabolic operons. This transitional repression saves the cell energy and allows efficient use of resources. In conditions of starvation, CodY relieves repression of genes involved in acquisition of nutrients and degradation of carbon sources (genes under selection). Here, we compare the …

Potential Antimicrobial Properties Of The Cyanobacterium Microcoleus Vaginatus In Relationship To The Moss Bryum Argenteum, Crystal Erickson, Lloyd Stark

Undergraduate Research Opportunities Program (UROP)

Biological soil crusts play important ecological roles in arid desert regions. These crusts cycle nutrients, prevent wind/water erosion, and form the basis of food chains and soil formation in desert communities. Primary components of these structures include two desert moss species Bryum argenteum and Syntrichia caninervis, and Microcoleus vaginatus, a cyanobacterium. Our Phase I experiment strongly suggests that in an environment of intense light, a condition of stress to Syntrichia caninervis, there is an increase in shoot regeneration when cyanobacteria are present compared to when they are absent. Microcoleus is a highly motile species and our lab observations of fewer …

Expression Of Thor Does Not Increase Desiccation Resistance In Drosophila Melanogaster, Robert L. Kobey, Deborah K. Hoshizaki, Allen G. Gibbs

Undergraduate Research Opportunities Program (UROP)

Using microarray analysis of Drosophila melanogaster, the Gibbs lab has identified several hundred candidate genes that may be involved in desiccation resistance. One of these genes is Thor, an important downstream target of the TOR/insulin signaling pathway. Preliminary results confirm that Thor plays a role in desiccation resistance. Further research will be needed to verify these results and understand the mechanism by which Thor increases desiccation resistance. This research will also serve as a proof-of-principle for testing microarray-derived hypotheses.

A previous microarray analysis found evidence that down-regulation of protein synthesis might be a cellular response to desiccation through the up-regulation …

Denitrification In Great Basin Hot Springs, Austin Mcdonald, Brian P. Hedlund

Undergraduate Research Opportunities Program (UROP)

Hydrogen has been proposed to fuel primary production in the Aquificae dominated hot springs of Yellowstone National Park (Spear, et al. 2005), a finding the authors generalized to all hot springs. However, clone libraries derived from Great Basin springs contain few 16S ribosomal RNA (rRNA) gene sequences from Aquificae and many from unknown microorganisms. In the same springs, alternative electron donors rival the reducing power of hydrogen. This project will try to cultivate the uncharacterized microbes of two Great Basin springs and determine which electron donors they can use.

Nitrogen is key to life. In its reduced form, ammonia, it …

Kinetics Of Bacillus Anthracis And Bacillus Cereus Spore Germination In Soil And The C. Elegans Intestine, Maclean Hall, Ernesto Abel-Santos

Undergraduate Research Opportunities Program (UROP)

Bacillus anthracis and Bacillus cereus are both described as soil bacteria, but are almost exclusively found as spores within the soil. Soil is generally not a nutrient-rich environment and may lack the amino acids and nucleosides necessary for spore germination and vegetative reproduction. We aim to determine if soil alone can cause germination in these two species in order to produce vegetative cells that can reproduce. In addition, nematodes, decaying meat, maggots, and plant roots will be tested for their ability to cause germination in these species.

Microbial Ecology Of Keane Wonder Spring, Death Valley National Park, Alexander B. Michaud, Duane P. Moser

Undergraduate Research Opportunities Program (UROP)

This research is focused on developing a better understanding of he physiological and phylogenetic diversity as well as environmental abundance of bacteria of the genus: Shewanella in selected desert ecosystems. Prior research from this laboratory has revealed that these bacteria are very abundant in sulfurand organic-rich aquatics habitats. We have selected a number of habitats for detailed investigation (cultivation, molecular ecology and relevant environmental chemistry) including the Tropicana Wash, spring in Death Valley, the lower Virgin River and possibly Big Soda Lame, Nevada.

Genomic Foundations Of Carbon Fixation In Bacteria Living In Hot Springs, Rachel K. Skinner, Brian P. Hedlund, Jeremy A. Dodsworth

Undergraduate Research Opportunities Program (UROP)

Photosynthesis does not occur above 73°C, so organisms living above this temperature must obtain useable carbon by some other mechanism. It is generally assumed that carbon is fixed by thermophiles through the process of chemolithoautotrophy; however, primary production has never been demonstrated to occur in hot springs >73°C. We have shown that two organisms, Thermocrinis and Pyrobaculum, make up more than 90% of the cells in an 80°C Great Basin hot spring, Great Boiling Spring. We hypothesize that these organisms fix carbon in the hot spring via the reverse tricarboxylic acid (rTCA) cycle. To test this hypothesis we will: i) …

Decoding The Protein Interaction Network - An Approach Integrating Biology And Math, Ryan Huang, Lingkun Gu, Qingxi J. Shen

Undergraduate Research Opportunities Program (UROP)

The WRKY super family is known to play a major role during the plant stress response and development. My project focuses on the protein-protein interaction of an Oryzasativa (rice) transcription factor, OsWRKY71 which functions as the repressor of gibberellins signaling pathway. Previous literature revealed that OsWRKY71 can interact with itself or OsWRKY51 to form dimmers by using bimolecular fluorescence complementation (BiFC). To confirm this result, we use yeast two-hybrid system. As our data showed, OsWRKY71 seems to suppress the reporter gene expression of the conventional yeast two-hybrid system, so we use a modified yeast two-hybrid, Mating-based Split Ubiquitin System (MbSUS). …

Constructing An Argf- Strain Of Bacillus Subtilis, Allison Faucher, Christine Pybus, Ronald E. Yasbin, Eduardo A. Robleto

Undergraduate Research Opportunities Program (UROP)

The goal of our research is to determine whether the level of transcription of a gene is correlated with the level of mutation in that gene. One factor involved in the mutability of a transcribed gene is the ability of the single stranded DNA to form secondary stem loop structures (SLS), in the wake of the transcription bubble, that contain unpaired mutable bases. We are interested in correlating the levels of mutation with transcription in the argF gene, which is predicted by bioinformatic analysis to be highly mutable. To achieve this goal, Allison will first construct a non-polar argF genetic …

Undergraduate Research Opportunities Program, University Of Nevada Las Vegas

Undergraduate Research Opportunities Program (UROP)

No abstract provided.

The Guacamole Fund Presents...

Native American Forum on Nuclear Issues

Special Bonnie Raitt Benefit Tickets

10th Annual Pacific Research Day Abstracts, University Of The Pacific

Excellence Day

No abstract provided.

Developing Accurate Spatial Maps Of Cotton Fiber Quality Parameters, Gretchen F. Sassenrath

Conference on Applied Statistics in Agriculture

Awareness of the importance of cotton fiber quality (Gossypium, L. sps.) has increased as advances in spinning technology require better quality cotton fiber. Recent advances in geospatial information sciences allow an improved ability to study the extent and causes of spatial variability in fiber parameters. However, these studies are often harvested by hand and ginned on small research gins. Fiber quality from cotton lint harvested and ginned in this manner is different from that machine-harvested and ginned on production-scale equipment. The objective of this study was to develop a method of correcting for error introduced into cotton fiber quality parameters …

Nonlinear Mixed Models To Evaluate Effects Of Environment Conditions, Hair Coat, And Anchor Length On Body Temperature During Afternoon Milking Of Holstein Cows In Hawaii, N Aitha, A. M. Parkhurst, C. N. Lee, P. E. Hillman

Conference on Applied Statistics in Agriculture

A hot thermal environment is one factor that causes loss of activity, productivity and even death in cows. One reason may be the effect of hair coat (black or white) on body temperature during different activities and environment conditions. In this study, we attempt to characterize the relationship between body temperature over time using activity, physiological and environmental effects with a nonlinear regression model. The fixed and mixed versions of models are examined. We also examine the effect of the measuring device, anchor length (long or short). Environmental effects, such as, air temperature, thermal heat index (THI), relative humidity, solar …

A Two-Stage Approach For Estimating The Effect Of Dna Methylation On Differential Expression Using Tiling Array Technology, Suk-Young Yoo, R. W. Doerge

Conference on Applied Statistics in Agriculture

Epigenetics is the study of heritable alterations in gene function without changing the DNA sequence itself. It is known that epigenetic modifications such as DNA methylation and histone modifications are highly correlated with the regulation of gene expression. A twostage analysis is proposed that employs a hidden Markov model and a linear model to evaluate differential expression as related to DNA methylation for the purpose of examining the effects of DNA methylation on gene regulation using tiling array technology. In the first stage, a hidden Markov model (HMM) is employed to estimate the methylation status per tile by utilizing information …

Spatial Clustering Using The Likelihood Function, April Kerby, David Marx, Ashok Samal, Viacheslav Adamchuk

Conference on Applied Statistics in Agriculture

Clustering has been widely used as a tool to group multivariate observations that have similar characteristics. However, most attempts at formulating a method to group similar multivariate observations while taking into account their spatial location are relatively ad hoc and do not account for the underlying spatial structure of the variables measured [12, 13, 14]. This paper proposes a method to spatially cluster similar observations based on the likelihood function. The geographic or spatial location of the observations can be incorporated into the likelihood of the multivariate normal distribution through the variance-covariance matrix. The variance-covariance matrix can be computed using …

Statistical Issues In Efficacy Evaluation For Companion Animal Drug Development, Zhanglin Lin Cui, Wherly Hoffman

Conference on Applied Statistics in Agriculture

Companion animals, commonly called pets, are animals such as dogs, cats, and horses. The companion animal drug market has expanded rapidly in recent years. Two major points of focus in companion animal drug development are therapeutics and parasiticides. From a statistics point of view, experimental design, experimental unit determination, sample size estimation and reestimation, treatment design, data transformation, multiple testing, and proper modeling are major statistical issues when efficacy evaluation in a companion animal study is conducted. These major statistical issues are addressed using two clinical studies as examples: Reconcile® (Fluoxetine) for the treatment of separation anxiety in dogs and …

Modeling Seasonal Wine Grape Development Using A Mixture Technique, William J. Price, Bahman Shafii, Paul E. Blom, Julie M. Tarara, Nick Dokoozlian, Luis J. Sanchez

Conference on Applied Statistics in Agriculture

Biological growth data typically display an increasing sigmoidal pattern over time. Grape development is no exception and shows a similar general trend. A detailed examination of the growth process in grapes, however, reveals a few systematic deviations from this pattern. Specifically, grape development is often characterized by localized areas of growth plateaus leading to an overall growth pattern referred to as a double sigmoidal curve. Capturing and characterizing these local changes in growth is important as they represent important phases in grape development such as veraison. This paper utilizes a model adapted from the technique of mixture models to estimate …