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Full-Text Articles in Life Sciences

Distribution And Abundance Of Anopheles Spp. In The Lower Rio Grande Valley, South Texas, Norma Hermelinda Martinez Dec 2013

Distribution And Abundance Of Anopheles Spp. In The Lower Rio Grande Valley, South Texas, Norma Hermelinda Martinez

Theses and Dissertations - UTB/UTPA

This study investigated the relationship between Anopheles abundance, collection sites and environmental variables in the Lower Rio Grande Valley, South Texas. In addition, species composition in the Lower Rio Grande Valley was determined in 2011. A total of 6772 female mosquitoes were identified to six genera and 27 species. The most prevalent genera collected were Culex (53.9%), Ochlerotatus (25.6%) and Aedes (13.6%). Anopheles mosquitoes were collected using resting boxes during summer 2012 at multiple locations along the Lower Rio Grande Valley. ArcGIS was used to identify land cover characteristics and nearest water sources at mosquito collection sites. Estero Llano Grande …


Greater Sage-Grouse (Centrocercus Urophasianus) Habitat Selection In Northwestern Wyoming And Stable Isotope Analysis Of Fecal Material, Andrea Renee Green Dec 2013

Greater Sage-Grouse (Centrocercus Urophasianus) Habitat Selection In Northwestern Wyoming And Stable Isotope Analysis Of Fecal Material, Andrea Renee Green

Graduate Theses and Dissertations

Dramatic range-wide declines in Greater Sage-Grouse populations have prompted efforts to determine habitat characteristics that are selected by sage-grouse for foraging, nesting and brood-rearing areas in an effort to conserve this species. Managers at Heart Mountain and Y U Bench in northwestern Wyoming expressed the need to quantify various habitat characteristics and to determine key use areas at both study sites. Data were collected on a variety of habitat variables in spots selected by grouse for foraging, nesting, and brood-rearing activities. These variables were compared to the same variables measured at random points at both study sites. Significant differences existed …


Characterization Of Caxck31, A Bacterial Calcium/Proton Antiporter, Marc Robert Ridilla Oct 2013

Characterization Of Caxck31, A Bacterial Calcium/Proton Antiporter, Marc Robert Ridilla

Open Access Dissertations

To better understand a class of transporters known as Calcium/Cation Antiporters (CaCAs), the bacterial calcium/proton antiporter CAXCK31 was purified and characterized. New methods were developed for its heterologous overexpression and purification. These methods help to define stress responses to toxic membrane overproduction in E. coli and may be broadly applicable to studies of membrane proteins. The results from a variety of biochemical and biophysical experiments demonstrated that CAXCK31 exists as a dimer in the membrane and can be purified in the dimeric state. The methods used include chemical cross-linking, FRET, and SEC-MALS. In addition, various transport properties of CAXCK31, including …


Examination Of Dietary Habits And Fruit And Vegetable Intake In A Chronic Disease Program, Qian Kuang Aug 2013

Examination Of Dietary Habits And Fruit And Vegetable Intake In A Chronic Disease Program, Qian Kuang

Theses and Dissertations - UTB/UTPA

The AHB program is a chronic disease prevention program which provides resources for community health centers along the U.S.-Mexico border. Healthy dietary habits and fruit/ vegetable intake play important roles in maintaining human health. Eight factors were used to evaluate the success of the AHB program. Another twenty factors were considered to predict dietary habits and fruit/vegetable intake status. Chi-square and multinomial logistic regression were used to study their correlation. Results from analysis showed that factors like birth country, employment, diabetes, baseline HbA1c, limited by problems, overall program quality, group, and program duration were correlated to the dietary habits, and …


Srs2 Prevents Rad51 Filament Formation By Repetitive Motion On Dna, Yupeng Qiu, Edwin Antony, Sultan Doganay, Hye Ran Koh, Timothy M. Lohman, Sua Myong Aug 2013

Srs2 Prevents Rad51 Filament Formation By Repetitive Motion On Dna, Yupeng Qiu, Edwin Antony, Sultan Doganay, Hye Ran Koh, Timothy M. Lohman, Sua Myong

Biological Sciences Faculty Research and Publications

Srs2 dismantles presynaptic Rad51 filaments and prevents its re-formation as an anti-recombinase. However, the molecular mechanism by which Srs2 accomplishes these tasks remains unclear. Here we report a single-molecule fluorescence study of the dynamics of Rad51 filament formation and its disruption by Srs2. Rad51 forms filaments on single-stranded DNA by sequential binding of primarily monomers and dimers in a 5′–3′ direction. One Rad51 molecule binds to three nucleotides, and six monomers are required to achieve a stable nucleation cluster. Srs2 exhibits ATP-dependent repetitive motion on single-stranded DNA and this activity prevents re-formation of the Rad51 filament. The same activity of …


Thorns Of Native Lower Rio Grande Valley Plants Are Colonized By Potentially Pathogenic Bacteria, Felicia A. Charles Aug 2013

Thorns Of Native Lower Rio Grande Valley Plants Are Colonized By Potentially Pathogenic Bacteria, Felicia A. Charles

Theses and Dissertations - UTB/UTPA

Epiphytic pathogenic bacteria on the thorns of native LRGV plants may provide a defense mechanism for the plants. To test this, plant thorns were collected from LRGV plant species and aerobic and anaerobic bacteria were isolated in thioglycollate medium. Tests were performed to characterize the bacterial cultures. The 16S rRNA gene was sequenced to allow for species identification. Sixty-nine bacterial cultures were isolated, including gram-positive and gram-negative cell types. All utilized a variety of carbon sources for nutrients and 23% of isolates displayed hemolysis. Bacterial identification included members of the genus Bacillus, Pseudomonas, Serratia, and others. Most were opportunistic pathogens. …


Sfmtp1 And Spmtp1 Cloning And Expression In Saccharomyces Cerevisiae: Potential For The Genetic Engineering Of Arabidopsis Thaliana, Elyssa Rae Garza Jul 2013

Sfmtp1 And Spmtp1 Cloning And Expression In Saccharomyces Cerevisiae: Potential For The Genetic Engineering Of Arabidopsis Thaliana, Elyssa Rae Garza

Theses and Dissertations - UTB/UTPA

To evaluate metal tolerance conferred by the overexpression of Metal Tolerance Protein 1 (MTP1) in transgenic non-accumulator plants such as Arabidopsis thaliana, a model system was developed in Saccharomyces cerevisiae containing either SfMTP1 cDNA, from the metal tolerant plant Streptanthus farnsworthianus, or SpMTP1 cDNA, from the hyperaccumulator Streptanthus polygaloides. Nonquantitative RT-PCR showed constitutive expression of MTP1 in both plant species. Alignment of SfMTP1 and SpMTP1 protein sequences shows a gap in SpMTP1 in a variable histidine region known to affect metal transport. Disk assays revealed SfMTP1 cDNA imparted greater Ni tolerance to yeast than SpMTP1 cDNA; however, SpMTP1 showed higher …


Predicted Effects Of Climate Change On The Distribution Of The Invasive Grass Dichanthium Annulatum, Cynthia Isabel Garcia May 2013

Predicted Effects Of Climate Change On The Distribution Of The Invasive Grass Dichanthium Annulatum, Cynthia Isabel Garcia

Theses and Dissertations - UTB/UTPA

Kleberg bluestem (Dichanthium annulatum) is an invasive grass species native to Africa but now found in southern United States, Mexico, and other tropical and subtropical countries throughout the world. Using the modeling software MaxEnt, climatic variables from WorldClim, the Intergovernmental Panel on Climate Change (IPCC) scenario A1B, and two General Circulatory Models: the Canadian model (Canadian Centre for Climate Modelling and Analysis or CCCMA), and the Australian model (Commonwealth Scientific and Industrial Research Organisation or CSIRO), several models were developed to determine the possible implications of climatic change on the suitable habitat for D. annulatum, in the year 2050. Models …


Evaluation Of Human Fecal Pollution In Mississippi Coastal And Creek Waters Using Library Independent Markers, Christopher John Flood May 2013

Evaluation Of Human Fecal Pollution In Mississippi Coastal And Creek Waters Using Library Independent Markers, Christopher John Flood

Dissertations

The objective of this study was to determine whether statistically valid correlations could be elucidated between standard indicator bacteria (enterococci and fecal coliforms) from coastal creek and marine samples and the presence of four library independent molecular markers that are human or sewage specific. Eight hundred and nineteen samples were collected between August 2007 and July 2010 to determine enterococcal and fecal coliform counts and the presence of genetic markers for sewage indicator organisms Methanobrevibacter smithii, human specific Bacteroides sp., Bacteroides thetaiotaomicron, and Fecalibacterium sp. During the course of this study environmental parameters were measured and statistically analyzed to determine …


Effects Of Food Dispersion On Dominance Related Behaviors In Garnett's Bushbaby (Otolemur Garnettii)?, Kyle Daniel Edens May 2013

Effects Of Food Dispersion On Dominance Related Behaviors In Garnett's Bushbaby (Otolemur Garnettii)?, Kyle Daniel Edens

Dissertations

Socio-ecological theorists tie primate social structure diversity to variations in habitats within which primate species reside. This premise permits laboratory researchers to investigate specific factors that influence or relate to social structure formation and maintenance. The focus of the current investigation was three fold. We first aimed to determine the relationships between traditional and non-traditional behavioral measures of dominance, then evidence for dominance hierarchy formation was examined, and various hypotheses were tested to discern if adjustments in the foraging context altered social behaviors in Garnett’s bushbaby (Otolemur garnettii). It was determined that animals likely to displace conspecifics were …


Interrelationships Between Testosterone, Aggression, And Parental Care Of A Temperate-Zone, Resident Songbird, The Northern Cardinal (Cardinalis Cardinalis), Margaret Susan Devries May 2013

Interrelationships Between Testosterone, Aggression, And Parental Care Of A Temperate-Zone, Resident Songbird, The Northern Cardinal (Cardinalis Cardinalis), Margaret Susan Devries

Dissertations

Interrelationships among testosterone (T), aggression, and parental care have received much investigative attention. Within birds, many studies have focused on examining such relationships using species characterized by relatively brief periods of territoriality and breeding. Few have investigated links between circulating T and reproductive behavior in birds that are year-round territorial residents and have lengthy breeding seasons, such as the Northern Cardinal (Cardinalis cardinalis). The following six chapters report and discuss findings from this dissertation’s examination of aspects of T production and potential interconnections with circulating T, aggression, and parental care in male and female cardinals. This work suggests …


Community Metrics And Trophic Dynamics In Tidal Creeks In An Anthropogenically Fragmented, Coastal Landscape, Michael Robert Lowe May 2013

Community Metrics And Trophic Dynamics In Tidal Creeks In An Anthropogenically Fragmented, Coastal Landscape, Michael Robert Lowe

Dissertations

Salt marsh landscapes are among the most anthropogenically altered ecosystems in the world. Urbanization (i.e., accumulation of impervious cover and man made structrues) of the coastal landscape can disrupt the delivery of numerous ecosystem services. Among the many services provided by salt marsh habitats, they serves as the primary habitats for distinct macroinfauna (i.e., benthic and epibenthic macrofauna) and nekton (i.e., fish and decapod crustaceans) assemblages. In this dissertation, I used a number of metrics to test the overarching hypothesis that coastal urbanization has negative consequences for salt marsh faunal assemblages. Chapter I uses a landscape ecology approach to show …


A Bird In The Binoculars: Understanding Birdwatchers' Potential To Contribute To Sustainable Development And Biological Conservation, Sheri Lynn Glowinski May 2013

A Bird In The Binoculars: Understanding Birdwatchers' Potential To Contribute To Sustainable Development And Biological Conservation, Sheri Lynn Glowinski

Dissertations

The three studies comprising this research drew from local economic development and environmental sociology to understand aspects of human dynamics that influence the conservation of birds. Using survey data collected from birdwatchers visiting coastal Alabama, the first study examined the local economic impact of birdwatching tourism and the factors that participants deemed important with respect to their recreation. Birdwatchers spent $103,305 during the four month study period. The total annual economic impact of this recreation on the area was estimated at $937,470, producing a multiplier of 1.48 and the equivalent of 20.3 full time jobs. Infrastructural variables (parking, bathrooms, site …


Internet Reviews: Ben (Biosciednet) Portal, John Creech Apr 2013

Internet Reviews: Ben (Biosciednet) Portal, John Creech

Library Scholarship

Review of the University of Michigan's BioSciEdNet Portal for use by undergraduates, graduate students, faculty instructors, and researchers.