Biology Commons^™

Observer Effects In Dna Profiling, Dan E. Krane

Biological Sciences Faculty Publications

No abstract provided.

Statistical Weights Of Mixed Dna Profiles, Dan E. Krane

Biological Sciences Faculty Publications

Presentation recording from December 2012 can be found at http://youtu.be/daRBTopFA1A.

Part of the Forensic DNA Profiling Video Series.

Implications Of Database Searches For Dna Profiling Statistics, Dan E. Krane

Biological Sciences Faculty Publications

No abstract provided.

Models Of Experimental Competitive Intensities Predict Home And Away Differences In Invasive Impact And The Effects Of An Endophytic Mutualist, Sa Xiao, Ragan M. Callaway, George Newcombe, Erik T. Aschehoug

Biological Sciences Faculty Publications

Understanding the role of competition in the organization of communities is limited in part by the difficulty of extrapolating the outcomes of small-scale experiments to how such outcomes might affect the distribution and abundance of species. We modeled the community-level outcomes of competition, using experimentally derived competitive effects and responses between an exotic invasive plant, Centaurea stoebe, and species from both its native and nonnative ranges and using changes in these effects and responses elicited by experimentally establishing symbioses between C. stoebe and fungal endophytes. Using relative interaction intensities (RIIs) and holding other life-history factors constant, individual-based and spatially explicit …

Positive Relationships Between Association Strength And Phenotypic Similarity Characterize The Assembly Of Mixed-Species Bird Flocks Worldwide, Hari Sridhar, Umesh Srinivasan, Robert A. Askins, Julio Cesar Canales Delgadillo, Chao-Chieh Chen, David N. Ewert, George A. Gale, Eben Goodale, Wendy K. Gram, Patrick J. Hart, Keith A. Hobson, Richard L. Hutto, Sarath W. Kotagama, Jessie Knowlton, Tien Ming Lee, Charles A. Munn, Somchai Nimnuan, B. Z. Nizam, Gillaume Péron, V. V. Robin, Amanda D. Rodewald, Paul G. Rodewald, Robert L. Thomson, Pranav Trivedi, Steven L. Van Wilgenburg, Kartik Shanker

Biological Sciences Faculty Publications

Competition theory predicts that local communities should consist of species that are more dissimilar than expected by chance. We find a strikingly different pattern in a multicontinent data set (55 presence-absence matrices from 24 locations) on the composition of mixed-species bird flocks, which are important sub-units of local bird communities the world over. By using null models and randomization tests followed by meta-analysis, we find the association strengths of species in flocks to be strongly related to similarity in body size and foraging behavior and higher for congeneric compared with noncongeneric species pairs. Given the local spatial scales of our …

A Study On The Function Of 14-3-3sigma In Regulating Cancer Energy Metabolism, Liem M. Phan, Liem M. Phan

Dissertations and Theses (Open Access)

Metabolic reprogramming has been shown to be a major cancer hallmark providing tumor cells with significant advantages for survival, proliferation, growth, metastasis and resistance against anti-cancer therapies. Glycolysis, glutaminolysis and mitochondrial biogenesis are among the most essential cancer metabolic alterations because these pathways provide cancer cells with not only energy but also crucial metabolites to support large-scale biosynthesis, rapid proliferation and tumorigenesis. In this study, we find that 14-3-3σ suppresses all these three metabolic processes by promoting the degradation of their main driver, c-Myc. In fact, 14-3-3s significantly enhances c-Myc poly-ubiquitination and subsequent degradation, reduces c-Myc transcriptional activity, and down-regulates …

Morphological Description Of Telaepolella Tubasferens N. G. N. Sp., Isolate Atcc©50593™, A Filose Amoeba In The Gracilipodida, Amoebozoa, Daniel J.G. Lahr, Gabriela M. Kubik, Anastasia L. Gant, Jessica Grant, O. Roger Anderson, Laura A. Katz

Biological Sciences: Faculty Publications

We describe the amoeboid isolate ATCC©50593™ as a new taxon, Telaepolella tubasferens n. g. n. sp. This multinucleated amoeba has filose pseudopods and is superficially similar to members of the vampyrellids (Rhizaria) such as Arachnula impatiens Cienkowski, 1876, which was the original identification upon deposition. However, previous multigene analyses place this taxon within the Gracilipodida Lahr and Katz 2011 in the Amoebozoa. Here, we document the morphology of this organism at multiple life history stages and provide data underlying the description as a new taxon. We demonstrate that T. tubasferens is distinct from Arachnula and other rhizarians (Theratromyxa, Leptophrys) in …

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

UNLV Theses, Dissertations, Professional Papers, and Capstones

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

Spatial And Temporal Trends Of Freshwater Mussel Assemblages In The Meramec River Basin, Missouri, Usa, J. E. Hinck, Stephen E. Mcmurray, Andrew D. Roberts, M. Christopher Barnhart, Christopher G. Ingersoll, Ning Wang, Tom Augspurger

College of Natural and Applied Sciences

The Meramec River basin in east-central Missouri has one of the most diverse unionoid mussel faunas in the central United States with .40 species identified. Data were analyzed from historical surveys to test whether diversity and abundance of mussels in the Meramec River basin (Big, Bourbeuse, and Meramec rivers, representing .400 river miles) decreased between 1978 and 1997. We found that over 20 y, species richness and diversity decreased significantly in the Bourbeuse and Meramec rivers but not in the Big River. Most species were found at fewer sites and in lower numbers in 1997 than in 1978. Federally endangered …

Mir-786 Regulation Of A Fatty-Acid Elongase Contributes To Rhythmic Calcium-Wave Initiation In C. Elegans, Benedict J. Kemp, Erik Allman, Lois Immerman, Megan Mohnen, Maureen A. Peters, Keith Nerhke, Allison L. Abbott

Biological Sciences Faculty Research and Publications

Background: Rhythmic behaviors are ubiquitous phenomena in animals. In C. elegans, defecation is an ultradian rhythmic behavior: every ∼50 s a calcium wave initiating in the posterior intestinal cells triggers the defecation motor program that comprises three sequential muscle contractions. Oscillatory calcium signaling is central to the periodicity of defecation. The posteriormost intestinal cells function as the pacemaker for this rhythmic behavior, although it is unclear how the supremacy of these cells for calcium-wave initiation is controlled.

Results: We describe how the loss of the mir-240/786 microRNA cluster, which results in arrhythmic defecation, causes ectopic intestinal calcium-wave initiation. mir-240/786 expression …

Effects Of A Chronic Increase In Plasma Corticosterone On The Brooding Behavior Of The Prairie Skink, Plestiodon Septentrionalis , Alexander James Anton

Student Work

The effects of chronic corticosterone (CORT) increases on the maternal behavior of the Prairie Skink, Plestiodon septentrionalis were studied in the laboratory during the summer of 2012. It was hypothesized that chronic increases in plasma CORT would result in decreased maternal effort and higher egg mortality, with similar results to analogous studies in birds. Plasma CORT was elevated using a non-invasive, exogenous treatment and behaviors were observed using video recordings. CORT treatments significantly reduced the amount of time spent tightly coiled around eggs in experimental individuals, and significantly decreased the amount of time experimental females spend in contact with their …

Fungal Biofilm Colonization And Succession On Artificial Reefs In The North-Central Gulf Of Mexico, Amy Leigh Salamone

Master's Theses

This study represents the first characterization of natural mixed-species fungal biofilm communities on artificial reefs in the marine environment. Previous fungal biofilm studies have failed to observe the naturally-occurring biodiversity in coastal areas, which comprise the most utilized zone of the marine environment. Artificial reefs can increase fishing yields, amplify oyster habitats, contribute to shoreline stabilization, promote good water quality, and deter pollution. Proper management practices of artificial reefs require knowledge of the colonization of these new habitats by marine organisms and their subsequent succession. Fungi, along with bacteria, archaea, protists, algae, and diatoms, quickly form a complex biofilm on …

Effect Of Rising Temperature Due To Ozone Depletion On The Dynamics Of A Prey-Predator System: A Mathematical Model, O. P. Misra, Preety Kalra

Applications and Applied Mathematics: An International Journal (AAM)

It is well recognized that the greenhouse gas such as Chlorofluoro Carbon (CFC) is responsible directly or indirectly for the increase in the average global temperature of the Earth. The presence of CFC is responsible for the depletion of ozone concentration in the atmosphere due to which the heat accompanied with the sun rays are less absorbed causing increase in the atmospheric temperature of the Earth. The increase in the temperature level directly or indirectly affects the dynamics of interacting species systems. Therefore, in this paper a mathematical model is proposed and analyzed using stability theory to asses the effects …

A Time Series Analysis Method Using Hidden Variables For Gene Network Reconstruction, Xi Wu

Dissertations

The DNA microarray technology can be applied to obtain time series data which contains thousands of genes and tens of time points. When confront the great amount of data points a fast and effective method must be constructed to extract useful information. The assumption that the interactions between genes are static in the time series data is made. After made the assumption how to reconstruct those interactions becomes a difficulty problem. Since the underlying interactions between genes are complicated, which involve transcription, translation and protein-protein interaction, to construct a model from physicochemistry is almost impossible/effortless. The popular methods constructed from …

The Role Of The Cysteine/Glutathione Regulatory Genes Cdo1, Gsh1, And Gsh2 In Yeast-Mold Dimorphism Of The Pathogenic Fungus Histoplasma Capsulatum, Melissa Anne Adams

Dissertations

The dimorphism of Histoplasma capsulatum (Hc) from a mold to yeast is regulated by many environmental factors such as temperature and thiol concentrations. Histoplasma exists in the soil (or in vitro at 25ºC) as a multicellular saprophytic mold. In the lungs of an infected host (or in vitro at 37ºC), a shift to the unicellular parasitic yeast occurs. Sulfhydryl groups (-SH), especially cysteine, are necessary in the culture medium for the mold to yeast transition. Cysteine is the precursor for the synthesis of glutathione. Enzymes involved in the cysteine metabolism pathway are being studied in order to evaluate …

Resistance Is Futile: The Bacteriocin Model For Addressing The Antibiotic Resistance Challenge, Margaret A. Riley, Sandra M. Robinson, Christopher M. Roy, Morgan Dennis, Vivian Liu, Robert Dorit

Biological Sciences: Faculty Publications

Pathogenic bacteria resistant to many or all antibiotics already exist. With the decline in microbiological research at pharmaceutical companies, the high rate at which resistance has evolved and spread has demanded a novel approach to addressing this critical human health issue. In the present paper, we propose a new paradigm in antibiotic discovery and development, one that applies ecological and evolutionary theory to design antimicrobial drugs that are more difficult and/or more costly to resist. In essence, we propose to simply adopt the strategies invented and applied by bacteria for hundreds of millions of years. Our research focuses on bacteriocins, …

Biogenic Amine Levels Correlate With Time Of Day, Age, Light Cycle, And Aggressive State In The Flesh Fly, Sarcophaga Crassipalpis, Veronica L. Fregoso

Electronic Theses and Dissertations

The biogenic amines serotonin (5HT), dopamine (DA), and octopamine (OA) have been indicated in the regulation of behaviors, including aggression. The flesh fly, Sarcophaga crassipalpis, was used to investigate ontogenetic and circadian changes in amines and aggression. Heads of male flies were analyzed for amine content using high performance liquid chromatography with electrochemical detection (HPLC-ECD) at 3 time points on each of 4 consecutive days in 2 light cycles, 12:12 LD and 15:9 LD. Both DA and OA levels decreased with age. Light-cycle dependent differences were observed for all amines in overall levels and patterns of change throughout the …

Molecular Phylogeny Of Microhylid Frogs (Anura: Microhylidae) With Emphasis On Relationships Among New World Genera, Rafael O. De Sá, Jeffrey W. Streicher, Relebohile Sekonyela, Mauricio C. Forlani, Simon P. Loader, Eli Greenbaum, Stephen Richards, Célio F.B. Haddad

Biology Faculty Publications

Background: Over the last ten years we have seen great efforts focused on revising amphibian systematics. Phylogenetic reconstructions derived from DNA sequence data have played a central role in these revisionary studies but have typically under-sampled the diverse frog family Microhylidae. Here, we present a detailed phylogenetic study focused on expanding previous hypotheses of relationships within this cosmopolitan family. Specifically, we placed an emphasis on assessing relationships among New World genera and those taxa with uncertain phylogenetic affinities (i.e., incertae sedis).

Results: One mitochondrial and three nuclear genes (about 2.8 kb) were sequenced to assess phylogenetic relationships. We utilized an …

Mutations In Stat3 Associated With Human Hyper Ige Syndrome Enhance Nfκb And Mapk-Mediated Gene Expression, Nathaniel Greeley

Dissertations and Theses (Open Access)

Hyper IgE syndrome (HIES) is a multisystem disorder resulting in bone and immune system abnormalities. It is associated with mutations in STAT3, which disrupt protein domains responsible for transcriptional function. Patients with HIES display osteoporosis and enhanced inflammatory cytokine production similar to hematopoietic Stat3-deficient mice. Since osteoclast and inflammatory cytokine genes are NFκB targets, these observations indicate a possible deregulation of NFκB signaling in both mice and humans with STAT3-deficiency. Here, we sought to examine the role of STAT3 in the regulation of NFκB-mediated gene expression through analysis of three HIES STAT3 point mutations in both hematopoietic and non- hematopoietic …

Tet1: A Unique Dna Demethylase For Maintenance Of Dna Methylation Pattern, Chunlei Jin

Dissertations and Theses (Open Access)

DNA methylation at the C5 position of cytosine (5-methylcytosine, 5mC) is a crucial epigenetic modification of the genome and has been implicated in numerous cellular processes in mammals, including embryonic development, transcription, X chromosome inactivation, genomic imprinting and chromatin structure. Like histone modifications, DNA methylation is also dynamic and reversible. However, in contrast to well defined DNA methyltransferases, the enzymes responsible for erasing DNA methylation still remain to be studied. The ten-eleven translocation family proteins (TET1/2/3) were recently identified as Fe(II)/2-oxoglutarate (2OG)-dependent 5mC dioxygenases, which consecutively convert 5mC into 5-hydroxymethylcytosine (5hmC), 5-formylcytosine and 5-carboxylcytosine both in vitro and in mammalian …

Gene Duplication And The Evolution Of Hemoglobin Isoform Differentiation In Birds, Michael T. Grispo

School of Biological Sciences: Dissertations, Theses, and Student Research

The majority of bird species co-express two functionally distinct hemoglobin (Hb) isoforms in definitive erythrocytes: HbA (the major adult Hb isoform, with α-chain subunits encoded by the α^A-globin gene) and HbD (the minor adult Hb isoform, with α-chain subunits encoded by the α^D-globin gene). The α^D-globin gene originated via tandem duplication of an embryonic α-like globin gene in the stem lineage of tetrapod vertebrates, which suggests the possibility that functional differentiation between the HbA and HbD isoforms may be attributable to a retained ancestral character state in HbD that harkens back to a primordial, …

Engineered, Harnessed, And Hijacked: Synthetic Uses For Cytoskeletal Systems, Brian S. Goodman, Nathan D. Derr, Samara L. Reck-Peterson

Biological Sciences: Faculty Publications

Synthetic biology re-imagines existing biological systems by designing and constructing new biological parts, devices, and systems. In the arena of cytoskeleton-based transport, synthetic approaches are currently used in two broad ways. First, molecular motors are harnessed for non-physiological functions in cells. Second, transport systems are engineered in vitro to determine the biophysical rules that govern motility. These rules are then applied to synthetic nanotechnological systems. We review recent advances in both of these areas and conclude by discussing future directions in engineering the cytoskeleton and its motors for transport.

Laboratory And Field Performance Of The Biosand Point Of Use Water Filtration System In The Artibonite Valley, Haiti, Andrew John Sisson

Masters Theses

The research presented here is summary two years of studying the Biosand filter (BSF) both in Haiti during March 2011 and in the laboratory. In Chapter 2, we examined the long term use and sustainability 55 BSF systems near Deschapelles, Haiti and 47% were found to be no longer in use. Interviews with BSF owners revealed problems related to intermittent filter use. A review of 17 BSF field studies also was included to compare and substantiate observations made in Haiti. Together, previous field studies and our observations point toward the importance of providing culturally appropriate technologies and education materials explaining …

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

UNLV Theses, Dissertations, Professional Papers, and Capstones

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

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

UNLV Theses, Dissertations, Professional Papers, and Capstones

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

Community Structure And Ecological Specialization In Plant-Ant Interactions, Paola Barriga

Graduate Theses and Dissertations

Positive associations among species have contributed to the maintenance of biodiversity. These interactions are typically studied in pairwise fashion where two interacting organisms are the focus. This dissertation uses network theory to analyze positive plant-ant associations in three Neotropical forests. Obligate plant-ant mutualisms were used, where plants host the ants in domatia and provide food bodies while the ants protect the plants and can feed them. A network approach was used to depict all obligate plant-ant interactions within a community. The main questions asked at the community level were: 1) Do network structure and levels of specialization change geographically and, …

Energy Development And Conservation Of Sympatric Wildlife: New Approaches To Meet Growing Challenges, William Christian Dunn

Biology ETDs

Conflicts between energy development and conservation of sympatric wildlife are becoming more acute as demand for energy increases. Resolving these conflicts is complex-- solutions must address the role of location, scale, and connectivity in persistence of populations. In Chapter 1, I use the MaxEnt species distribution model and pertinent climate variables to predict the natural distribution of the Lesser Prairie Chicken (LPC) (Tympanuchus pallidicinctus), a prairie grouse adversely affected by habitat loss from energy development. Within the geographic range of LPC, precipitation was strongly associated with its distribution in the north, whereas temperature was strongly associated with its distribution in …

Effects Of Climate Change Upon Birds In The Mojave And Sonoran Deserts, Harinamsimran Kaur Khalsa

Biology ETDs

Climate change has increasingly become an area of concern in relation to ecological communities. In this study, climatic signals were investigated to determine whether bird diversity indices in the Breeding Conservation Region (BCR) of the Mojave and Sonoran Deserts were related (1) to the oceanic/atmospheric systems El Nino Southern Oscillation (ENSO), the Pacific Decadal Oscillation (PDO), and/or the Atlantic Multidecadal Oscillation (AMO); (2) to regional moisture influences determined by the Palmer Drought Severity Index (PDSI); and (3) to local precipitation and temperature. Specifically, an examination was conducted to determine the relationship between climatic variables for thirteen bird species, total abundance …

Genetic Diversity, Local Differentiation, And Adaptive Evolution In Introduced Populations Of The Invasive Plant Isatis Tinctoria L. (Brassicaceae), Heather L. Simpson

Biology ETDs

Populations of invasive species are often characterized as genetically depauperate, an inherent consequence of the colonization process. It has also been suggested that species that are able to avoid these reductions in genetic diversity may be better able to adapt to their introduced range. Evolutionary change can play an important role in the invasion process if novel selective pressures drive adaptive evolution. Species that are able to avoid reductions in genetic diversity associated with colonization may be better able to adapt to their introduced range. To better understand the genetic processes following invasion, introduced populations of the invasive mustard, Isatis …

Conservation Genetics Of A Spotted Salamander (Ambystoma Maculatum (Shaw 1802)) Local Population In Southeast Tennessee, Daniel Scott Armstrong

Masters Theses and Doctoral Dissertations

Currently there is a worldwide amphibian decline with numerous causes. Because of this, it is important to understand how genetic variation in local amphibian populations is affected by disturbance. The goal of this study was to assess the genetic impacts of past chemical and ammunition storage and present industrialization on a local population of Ambystoma maculatum (Shaw 1802) using thirteen microsatellite markers. Most loci exhibited no loss of heterozygosity but the low effective population size may indicate vulnerability to future declines. No population substructure or sex-biased dispersal was detected. Possible explanations for the reduction in genetic diversity at four loci …