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Full-Text Articles in Life Sciences

Ecology Of The Rock Rattlesnake, Crotalus Lepidus, In The Northern Chihuahuan Desert, Vicente Mata Silva Jan 2011

Ecology Of The Rock Rattlesnake, Crotalus Lepidus, In The Northern Chihuahuan Desert, Vicente Mata Silva

Open Access Theses & Dissertations

The Rock Rattlesnake, Crotalus lepidus is a small species that is found from southern Arizona, southern New Mexico, and southern Texas, in the U.S., into northern Mexico. To date, little is known about the ecology of this species. Ecological information is becoming desperately needed for supporting the conservation and protection of species living in fragile environments such as the Chihuahuan Desert amid current local and global threats (e.g., habitat destruction and modification, urban development, and climate change). Although rattlesnakes spend a significant amount of time underground while overwintering, little is known about the physiology and behavior of these organisms during …


The Influence Of Schwartz's Values On Teachers' Internet Usage: A Quantitative Study Of Cross Cultural Differences Between European Nations, Meghana Aleti Jan 2011

The Influence Of Schwartz's Values On Teachers' Internet Usage: A Quantitative Study Of Cross Cultural Differences Between European Nations, Meghana Aleti

Open Access Theses & Dissertations

This study investigated the Impact of human values on teacher Internet usage at individual levels across various nations. Schwartz's higher order values: Openness to Change, Conservation, Self-Enhancement, and Self-Transcendence are used as value variables. Teachers' are categorized as primary education, secondary education or college level. College teachers showed heavy Internet use when compared to secondary and primary teachers. Conservation higher order value was most significant among college teachers. Openness to Change and Self-Enhancement values are positively correlated with heavy Internet use among various nations. This study should be of interest to education and policy makers interested in comparison of Internet …


Gender Differences In The Processing Of Acute And Repeated Stress, Jaidee Zavala Jan 2011

Gender Differences In The Processing Of Acute And Repeated Stress, Jaidee Zavala

Open Access Theses & Dissertations

Chronic stress is implicated in the pathogenesis of a variety of diseases, including affective, immune and cardiovascular disorders, which are differentially experienced by men and women. Corticotropin-releasing factor (CRF), arginine vasopressin (AVP), and glucocorticoid receptor (GR) are the major regulators of the stress response and are widely expressed in the paraventricular nucleus of the hypothalamus (PVH), where adaptive responses to stress are generated. Adult male and female rats were subjected to single (acute) or 14 consecutive daily (repeated) 30 min restraint sessions, or maintained as unstressed controls. Rats were perfused after their final restraint, and their brain tissues sectioned and …


Validating The Nike+ Wireless Sport Kit For Estimating Pace, Distance, And Energy Expenditure During Treadmill Walking And Running, Derek Joseph Acosta Jan 2011

Validating The Nike+ Wireless Sport Kit For Estimating Pace, Distance, And Energy Expenditure During Treadmill Walking And Running, Derek Joseph Acosta

Open Access Theses & Dissertations

The use of accelerometry based physical activity monitors among recreational athletes to meet or exceed recommended physical activity guidelines has grown in popularity. In the interest of capitalizing on this demand, Adidas developed the miCoach Pacer System which allows the user to observe pace, distance, and energy expenditure during walking or running. Purpose. To validate the accuracy of the Adidas miCoach activity monitor in estimating energy expenditure (EE) (kcal/min), pace (min/km), and distance (km) during treadmill walking and running, and for two different sensor configurations. Methods. Nine male and 9 female moderately endurance trained volunteers (mean ± SD age: 28.83 …


Prediction Of Ribonucleic Acid Secondary Structures Using A Heuristic Backtracking Search, Christopher Roman Cuellar Jan 2011

Prediction Of Ribonucleic Acid Secondary Structures Using A Heuristic Backtracking Search, Christopher Roman Cuellar

Open Access Theses & Dissertations

Ribonucleic acid (RNA) is essential for all forms of life. RNA is made up of a large chain of nucleotide bases: Guanine (G), Uracil (U), Cytosine (C), and Adenine (A). An RNA strand can fold on itself to allow G-C, A-U, and G-U bases to form hydrogen bonds, this is known as a secondary structure. Knowing the secondary structure of an RNA chain is very important because it will allow researchers to better understand its specific functions. RNA will create secondary structures that tend to minimize their free energy. RNA secondary structure prediction is the attempt to predict physical folding …


Inhibition Of Calcium Oxalate Calculi By Ndga - A Spectroscopic Study, Preethi Dacha Jan 2011

Inhibition Of Calcium Oxalate Calculi By Ndga - A Spectroscopic Study, Preethi Dacha

Open Access Theses & Dissertations

Formation of calculi in urinary tract leads to kidney stones. This process is known as Urolithiasis. Some of the causes of urolithiasis are metabolic disorders, genetic factors, and anatomic abnormalities in the urinary system. Nowadays, urolithiasis is very common disease in population of all over the world. The present study strives to understand calcium oxalate calculi formation as well as its inhibition by using Nordihydroguaiaretic acid (NDGA), which is a chemical extract of the Larrea Tridentata bush, a plant that is traditionally employed in the El paso region as a natural treatment for kidney stones and bladder diseases. Thus, in …


Monitoring Ecosystem Dynamics In An Arctic Tundra Ecosystem Using Hyperspectral Reflectance And A Robotic Tram System, Santonu Goswami Jan 2011

Monitoring Ecosystem Dynamics In An Arctic Tundra Ecosystem Using Hyperspectral Reflectance And A Robotic Tram System, Santonu Goswami

Open Access Theses & Dissertations

Global change, which includes climate change and the impacts of human disturbance, is altering the provision and sustainability of ecosystem goods and services. These changes have the capacity to initiate cascading affects and complex feedbacks through physical, biological and human subsystems and interactions between them. Understanding the future state of the earth system requires improved knowledge of ecosystem dynamics and long term observations of how these are being impacted by global change. Improving remote sensing methods is essential for such advancement because satellite remote sensing is the only means by which landscape to continental-scale change can be observed.

The Arctic …


Distributional Properties Of Inversions And Segmentation Algorithms For Rna Sequences, Sameera Dhananjaya Viswakula Jan 2011

Distributional Properties Of Inversions And Segmentation Algorithms For Rna Sequences, Sameera Dhananjaya Viswakula

Open Access Theses & Dissertations

Ribonucleic acid (RNA) is a long single stranded molecule made up of four types of nucleotide bases: Adenine (A), Cytosine(C), Guanine (G) and Uracil (U). It folds back on itself and forms C-G and A-U complementary base pairs. The set of such hydrogen-bonded pairs in an RNA molecule is called its secondary structure. Knowing the secondary structure of RNA is useful for understanding its biological function. Prediction of RNA secondary structure from the nucleotide sequence has been an important bioinformatics problem for over two decades.

The work in this thesis is motivated by the need to improve the secondary structure …


The Effects Of Tai Chi On Balance And Peripheral Somatosensation In Older Adults With Type 2 Diabetes, Elisabeth Inge Cavegn Jan 2011

The Effects Of Tai Chi On Balance And Peripheral Somatosensation In Older Adults With Type 2 Diabetes, Elisabeth Inge Cavegn

Open Access Theses & Dissertations

The increasing prevalence of type 2 diabetes in older adults is a major health concern, as older adults with diabetes have a two- to threefold risk of injurious falls and physical disability. Although studies on the effects of Tai Chi on balance and fall prevention have increased over the last two decades, the benefits for older adults with diabetes, specifically for those with impaired somatosensation in the lower extremities, are limited. Therefore, the purpose of this study was to investigate the effects of Tai Chi exercise on balance, peripheral somatosensation, and fitness in older adults with type 2 diabetes. The …


A Taxonomic Revision Of The New World Hypoponera Santschi, 1938 (Hymenoptera: Formicidae), Shawn Thomas Dash Jan 2011

A Taxonomic Revision Of The New World Hypoponera Santschi, 1938 (Hymenoptera: Formicidae), Shawn Thomas Dash

Open Access Theses & Dissertations

The New World taxa of the pantropic ant genus Hypoponera (Ponerinae: Ponerini) is revised for the first time. The 55 previously recognized taxa have been evaluated using morphological and, when possible, ecological and biogeographical data to resolve taxon validity and species limits. Currently I recognize 42 species of Hypoponera , a number of which are new. I propose the following taxonomic outline: Hypoponera agilis (Borgmeier), Hypoponera aliena (F. Smith), Hypoponera antoniensis (Forel) stat. nov., Hypoponera apateae sp. nov., Hypoponera capilosa sp. nov., Hypoponera clinei sp. nov., Hypoponera clavatula (Emery) [= fiebrigi (Forel) syn. nov., = neglecta (Santschi) syn. nov.], Hypoponera …


Altered Leptin Signaling On Dendritic Cells As A Potential Mechanism For Cancer Immunotherapy, Lorena Y. De Los Santos Jan 2011

Altered Leptin Signaling On Dendritic Cells As A Potential Mechanism For Cancer Immunotherapy, Lorena Y. De Los Santos

Open Access Theses & Dissertations

Leptin is a pleiotropic hormone synthesized primarily by white adipocytes and its receptors are expressed in a variety of tissues and cells such as in the hypothalamus and cells of the immune system. Multiple cell types can produce a considerable amount of leptin such as skeletal muscle, placenta, and osteoblasts to name a few and its synthesis has been shown to be regulated by sex hormones and a broad range of inflammatory mediators. Although leptin has been shown to directly affect immune response, we are interested in how leptin affects dendritic cell function and their ability to induce a proper …


Structural And Functional Investigation Of Φ-El-Chaperonin Mediated Protein Folding, Sudheer Kumar Molugu Jan 2011

Structural And Functional Investigation Of Φ-El-Chaperonin Mediated Protein Folding, Sudheer Kumar Molugu

Open Access Theses & Dissertations

Chaperonins are ubiquitous, sequence related protein complexes that aid in the folding of nascent and misfolded polypeptides in an ATP driven pathway. Recently a GroEL-like, 860 kilo Dalton chaperonin protein complex was identified and isolated from the bacteriophage EL, a virus that infects the Gram-negative bacterium Pseudomonas aeruginosa. The bacteriophage EL contains 201 predicted open reading frames and is the only known phage that encodes for its own chaperonin known as Φ-EL-chaperonin.

To understand the importance of Φ-EL-chaperonin in phage EL life cycle, the recombinant Φ-EL-chaperonin protein was expressed in Escherichia coli (E. coli) purified to homogeneity and the structure …


Identification And Characterization Of Fkbp52-Specific Inhibitors For The Treatment Of Prostate Cancer, Johanny Tonos De Leon Jan 2011

Identification And Characterization Of Fkbp52-Specific Inhibitors For The Treatment Of Prostate Cancer, Johanny Tonos De Leon

Open Access Theses & Dissertations

Steroid hormone receptors require the ordered assembly of various chaperone and cochaperone proteins in order to reach a functional state. The final stage in the receptor maturation process requires the formation of a mutimeric complex consisting of Hsp90 dimer, p23, and one of several large immunophilins. Studies conducted previously demonstrated that the large immunophilin FKBP52 acts to potentiate glucocorticoid, androgen, and progesterone receptor signaling pathways. The aim of these studies was to identify and characterize FKBP52-specific inhibitors that would not only serve as tools for the pharmacological analysis of FKBP52-receptor interactions, but may also lead to novel drugs with significant …


Development Of A Novel Metallo-Lipid Microparticle Delivery System For A Leishmania Mexicana Dna Vaccine Candidate, Joanna B. Valencia Jan 2011

Development Of A Novel Metallo-Lipid Microparticle Delivery System For A Leishmania Mexicana Dna Vaccine Candidate, Joanna B. Valencia

Open Access Theses & Dissertations

ABSTRACT

Background and Significance.

The leishmaniases are an important group of neglected tropical parasitic diseases caused by parasitic protozoa of the genus Leishmania. International health authorities estimate that 350 million people around the world are at risk for contracting leishmaniasis. Two million new cases occur each year and 12 million people are presently infected worldwide. Leishmaniasis is endemic throughout the Americas region including all of Central America, most of South America, Mexico and southern Texas. Leishmania is also considered a threat to the military readiness of U.S. troops deployed to the Middle East or Latin America.

First- and second-line treatments …


Causes And Consequences Of Changes In Algal Community Structure Of Arctic Tundra Ponds From Barrow, Alaska, Mariana Vargas Medrano Jan 2011

Causes And Consequences Of Changes In Algal Community Structure Of Arctic Tundra Ponds From Barrow, Alaska, Mariana Vargas Medrano

Open Access Theses & Dissertations

Algal communities in the Arctic are highly sensitive to environmental change, such as longer growing seasons and changes in ice cover. On the north slope of Alaska, ponds and lakes cover large portions of the total land area. We surveyed the periphytic algal communities in tundra ponds from Barrow, Alaska to assess environmental effects on their populations. Samples were collected in August 2008-10 from two main study areas: the IBP (the International Biological Program), which was also studied in 1970-71 but now is located near to human settlements, and the BEO (Barrow Environmental Observatory), which is within a protected area. …


Computational Methods Of Hidden Markov Models With Respect To Cpg Island Prediction In Dna Sequences, Roberto Angel Ortega Jan 2011

Computational Methods Of Hidden Markov Models With Respect To Cpg Island Prediction In Dna Sequences, Roberto Angel Ortega

Open Access Theses & Dissertations

Hidden Markov models (HMM's) are a specific case of Markov models where, contrary to Markov chains, the observer is unaware of what state the model was in when the symbol is observed. Like Markov chains, HMM's assume that the future state of a sequence is dependent only on the current state of the sequence. The parameters associated with HMM's are transition and emission probabilities, where transition probabilities are associated with the probability of transitioning from one state to another, and emission probabilities are the probabilities associated with observing a symbol given it came from a specific state.

The structure of …


Isometric Neck Strength In Concussed And Non-Concussed High School Football Players, Cameron Layne Raschke Jan 2011

Isometric Neck Strength In Concussed And Non-Concussed High School Football Players, Cameron Layne Raschke

Open Access Theses & Dissertations

Football accounts for a significant portion of the 1.275 million concussions per year. Neck strength has been theorized to possibly assist in the attenuation of severe impacts and possibly prevent football-related concussions. The purpose of this study was to investigate potential differences in isometric neck strength in flexion, extension, and lateral flexion right/left between concussed high school football players and matched non-concussed football players. Sixteen high school players that suffered a football-related concussion during the 2010 competition season comprised the research group, and were later matched to a player that did not suffer a concussion, on the basis of age, …


Phospholipid Analysis In Trypanosoma Cruzi, Melissa Rashonda Harris Jan 2011

Phospholipid Analysis In Trypanosoma Cruzi, Melissa Rashonda Harris

Open Access Theses & Dissertations

Chagas disease, caused by the flagellate protozoan Trypanosoma cruzi is one of the most endemic and deadly infectious diseases. T.cruzi is distributed throughout most of South and Central America, where it infects 12 to 19 million people, with an annual incidence of 561,000. Another 35 million are exposed to infection, 2 to 3 million people have clinical symptoms of chronic Chagas disease, and about 45,000 of these may die every year due to cardiac failure. In addition to the growing number of incidences in other countries the disease is an emerging infectious disease in the U.S due to the migration …


Synthesis, Self-Assembly And Biological Properties Of Self-Folding Cu(Ii) Coordination Polymers, Alejandro Arzola-Rubio Jan 2011

Synthesis, Self-Assembly And Biological Properties Of Self-Folding Cu(Ii) Coordination Polymers, Alejandro Arzola-Rubio

Open Access Theses & Dissertations

The synthesis of materials via molecular self-assembly is a powerful bottom-up approach for fabricating matter in the nano- and micro-meter scales. This methodology involves the spontaneous and reversible organization of small molecules that interact with one another to create larger structures driven by non-covalent interactions such as hydrogen bonding, hydrophobic forces and metal-ligand coordination interactions. In this thesis, the design, synthesis and characterization of a new set of molecules that spontaneously self-organize in water to form three-dimensional nanoscale toroidal structures was investigated. These supramolecular structures were designed with an intrinsic affinity to bind and condense DNA strands with the intent …


Phylogeography Of Northern Populations Of The Black-Tailed Rattlesnake (Crotalus Molossus Baird And Girard, 1853) With The Revalidation Of C. Ornatus Hallowell, 1854, Christopher Anderson Jan 2011

Phylogeography Of Northern Populations Of The Black-Tailed Rattlesnake (Crotalus Molossus Baird And Girard, 1853) With The Revalidation Of C. Ornatus Hallowell, 1854, Christopher Anderson

Open Access Theses & Dissertations

The black-tailed rattlesnake (Crotalus molossus Baird and Girard, 1853) is a wide-ranging species complex with representatives from the southwestern United States through the highlands of central and southern Mexico. The systematics of this group has received little attention and in the past six decades only two taxonomic revisions have been proposed (the transfer of C. basiliscus oaxacus to C. molossus and the elevation of C. m. estebanensis to full species). However, a recent revision of the Neotropical rattlesnakes (C. durissus and C. simus) recovered a polyphyletic C. molossus. Sequenced data were obtained from three mitochondrial genes …


The Role Of Dopamine In Operant Learning And Memory, Jennifer Leigh Johnson Jan 2011

The Role Of Dopamine In Operant Learning And Memory, Jennifer Leigh Johnson

Open Access Theses & Dissertations

Dopamine is a neurotransmitter that regulates many physiological processes including reward, motivation, movement, learning and memory, and reinforcement. The cognitive processes in which one associates a specific action or behavior with a positive or negative consequence is referred to as operant learning, and is a robust occurrence in everyday life. It is also believed to play a significant role in the development of drug addiction and has been shown that increased levels of dopamine are associated with the intake of addictive drugs such as cocaine and alcohol; however, the underlying cellular mechanisms of this learned behavior are not well understood. …


Free Radical Stress-Induced Parkinsonian Lewy-Like Aggregation Prevented Through Polyphenolic Phytochemical Analog Intervention: Implications For Subcellular Trafficking And Neurodegenerative Disorders, Rituraj Pal Jan 2011

Free Radical Stress-Induced Parkinsonian Lewy-Like Aggregation Prevented Through Polyphenolic Phytochemical Analog Intervention: Implications For Subcellular Trafficking And Neurodegenerative Disorders, Rituraj Pal

Open Access Theses & Dissertations

Protein disulfide isomerase (PDI), the chief endoplasmic reticulum (ER)-resident oxidoreductase chaperone, is known to catalyze the maturation of disulfide-bond-containing proteins primarily through oxidation-reduction and isomerization functions. The rate-determining step in the oxidative regeneration path of disulfide-bond-containing proteins generally couples chemical thiol-disulfide-exchange reactions to a physical conformational folding reaction. I have determined the impact of PDI and its subdomains on the rate-determining step in ribonuclease A folding and on the physical structure-forming step of select ER-processed proteins including RNase A. This was facilitated through application of a novel chemical tool to exclusively populate native-disulfide-containing intermediates in unstructured forms. The described biochemical …


Molecular Mechanisms Of Poly [Adp-Ribose] Polymerase-1 In Hiv-1 Infection, Daniel Reyes Jan 2011

Molecular Mechanisms Of Poly [Adp-Ribose] Polymerase-1 In Hiv-1 Infection, Daniel Reyes

Open Access Theses & Dissertations

Poly (ADP-ribose) polymerase-1 (PARP-1) is a cellular enzyme involved in genome stability and transcriptional regulation. The role of this protein in HIV-1 infection is largely controversial. Some reports indicated a fundamental role of PARP-1 in HIV-1 DNA integration and results from other laboratories do not support these conclusions. An important characteristic in all these experiments is that the HIV-1 target cells that were used express, in addition to PARP-1, the functional homologue PARP-2. We evaluated the role of PARP-1 in the chicken B lymphoblastoid cell line DT40. These cells naturally lack PARP-2 and support the early steps of HIV infection. …


Development And Testing Of An Unmanned Aircraft System For Environmental Science, Jerald James Brady Jan 2011

Development And Testing Of An Unmanned Aircraft System For Environmental Science, Jerald James Brady

Open Access Theses & Dissertations

For some environmental science applications, Unmanned Aircraft Systems (UASs) are increasingly recognized for their capacity to collect remotely sensed data in a safer, more efficient and effective manner than is permitted with manned aircraft and satellite remote sensing platforms. To date, however, technological, human, and other challenges have constrained adoption of UASs in the environmental sciences. This study developed and tested a new UAS for an archetypical environmental science research group (stakeholder) composed of non-UAS experts. Specifically, this thesis: 1) Assessed the research and operational needs of the stakeholder to determine the optimum UAS platform; 2) Developed an Unmanned Aerial …


Ecogeographical Distribution Of The Herpetofauna Of Indio Mountains Research Station, Hudspeth County, Texas, Ross Owen Couvillon Jan 2011

Ecogeographical Distribution Of The Herpetofauna Of Indio Mountains Research Station, Hudspeth County, Texas, Ross Owen Couvillon

Open Access Theses & Dissertations

Indio Mountain Research Station (IMRS) in Trans-Pecos, Texas is dominated by Chihuahuan Desert scrub vegetation, but a complexity of plant communities exist relating to elevation, slope, and geologic formations. Surrounding the Indio Mountains are desert grasslands with various desert scrub associations. This mosaic of habitats forms a unique assemblage of amphibians and reptiles. The goal of this study was to determine if the current number of amphibians, turtles, lizards, and snakes (43 species) of IMRS was accurate and identify which biotic and abiotic factors define the distribution of these species. Records from the last approximately 25 years were used to …


Comparison Of Four Methods Of Dietary Assessment: Food Records Vs. Combined Food Records With Digital Photography, Sara Lynne Peidle Jan 2011

Comparison Of Four Methods Of Dietary Assessment: Food Records Vs. Combined Food Records With Digital Photography, Sara Lynne Peidle

Open Access Theses & Dissertations

Methods for collecting dietary intakes of free-living individuals have been studied over the past century and there are many limitations. Collection of dietary intakes from individuals is best done in food diary format and researchers have investigated both written and photographic records. The purpose of this study was to add to the body of literature on studies of collecting dietary intakes by comparing written food records (FR), digital food records (DP), written and digital food records combined (FRDP), and digital food records with limited documentation (DPR) to one another and to a known, criterion value. This study included 50 Registered …


Computational Tool For Automated Large-Scale Gpiomic Analysis, Juan Clemente Aguilar Jan 2011

Computational Tool For Automated Large-Scale Gpiomic Analysis, Juan Clemente Aguilar

Open Access Theses & Dissertations

Liquid chromatography-tandem mass spectrometry (LC-MS/MS or MS/MS) is the most efficient tool today for the identification of glycosylphosphatidylinositol (GPI) molecules. The amount of data produced in each MS/MS experiment is a major bottleneck in high-throughput GPIomic (the entire collection of free and protein-linked GPIs) projects. Efficient computational tools can significantly reduce the amount of time analyzing MS/MS data; however, at present the automatic interpretation of these data to annotate GPI structures is absent. We propose a library-based tool to identify GPI structures by matching fragment peaks in the spectra with data derived from a theoretical database of GPI structures that …


Effect Of An Injury Prevention Training Program On Risk Factors Associated With Acl Injury, Daniel Medrano Jan 2011

Effect Of An Injury Prevention Training Program On Risk Factors Associated With Acl Injury, Daniel Medrano

Open Access Theses & Dissertations

Increased involvement in women's sports has been met with a disproportionate incidence of anterior cruciate ligament (ACL) injuries. The underlying cause of ACL injury is likely multi-factorial, with risk factors including deficits in lower extremity kinematics, kinetics, muscle activity, strength, stability, and sensitivity. Insight into risk factors has prompted several injury prevention programs. However, program outcomes have been mixed. Therefore, the purpose of this study was to examine the effect of specialized training on risk factors theorized to increase the incidence of ACL injury.

Fifty-six (28 control, 28 intervention) apparently healthy females volunteered to participate in this study. Training was …


Assessing Data Quality In A Sensor Network For Environmental Monitoring, Gesuri Ramirez Jan 2011

Assessing Data Quality In A Sensor Network For Environmental Monitoring, Gesuri Ramirez

Open Access Theses & Dissertations

Assessing the quality of sensor data in environmental monitoring applications is important, as erroneous readings produced by malfunctioning sensors, calibration drift, and problematic climatic conditions, such as icing or dust, are common.Traditional data quality checking and correction is a painstaking manual process, so the development of automatic systems for this task is highly desirable.

This study investigates machine learning methods to identify and clean incorrect data from a real-world environmental sensor network, the Jornada Experimental Range, located in Southern New Mexico. We evaluated several learning algorithms and data replacement schemes, and developed a method to identify the problematic sensor. The …