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Full-Text Articles in Life Sciences

Constraints On Patterns Of Abundance And Aggregation In Biological Systems, Kenneth J. Locey Dec 2013

Constraints On Patterns Of Abundance And Aggregation In Biological Systems, Kenneth J. Locey

All Graduate Theses and Dissertations

Understanding the mechanisms that structure biological systems is a primary goal of biology. My research shows that the biological structure is constrained in important ways by general variables such as the number of base pairs in a genome and the number of individuals and species in a community. I used a combination of macroecology, bioinformatics, statistics, mathematics, and advanced computing to pursue my research and published several peer-reviewed scientific manuscripts and open-source software as a result.
I was funded through a combination of fellowships and scholarships awarded by the Utah State University School of Graduate Studies, College of Science, and ...


The Ecology And Genetics Of Schoenoplectus Maritimus, An Important Emergent Macrophyte, Across Diverse Hydrologic Conditions--Implications For Restoration, Amanda Clare Sweetman Aug 2013

The Ecology And Genetics Of Schoenoplectus Maritimus, An Important Emergent Macrophyte, Across Diverse Hydrologic Conditions--Implications For Restoration, Amanda Clare Sweetman

All Graduate Theses and Dissertations

Revegetation projects in wetlands are challenging due to questions surrounding where to obtain plant materials and how hydrologic conditions, which are often unpredictable at restoration sites, may impact restoration success. We used a two-pronged approach to inform decisions on seed sourcing. Our study species, Schoenoplectus maritimus (alkali bulrush), is a widely distributed wetland plant. First, we investigated how genetic diversity was partitioned within and among populations of S. maritimus. We found five weakly differentiated populations and one distinct population. We found high levels of genetic diversity with the majority (92%) of diversity found within rather than among sites (8%). Also ...


Utilizing Remote Sensing And Geospatial Techniques To Determine Detection Probabilities Of Large Mammals, Patricia A. Terletzky Aug 2013

Utilizing Remote Sensing And Geospatial Techniques To Determine Detection Probabilities Of Large Mammals, Patricia A. Terletzky

All Graduate Theses and Dissertations

Whether a species is rare and requires protection or is overabundant and needs control, an accurate estimate of population size is essential for the development of conservation plans and management goals. Wildlife censuses in remote locations or over extensive areas are logistically difficult, frequently biased, and time consuming. My dissertation examined various techniques to determine the probability of detecting animals using remotely sensed imagery. We investigated four procedures that integrated unsupervised classification, texture characteristics, spectral enhancements, and image differencing to identify and count animals in remotely sensed imagery. The semi-automated processes had relatively high errors of over-counting (i.e., greater ...


Presence And Function Of Tetrodotoxin In Terrestrial Vertebrates And Invertebrates, Amber N. Stokes Aug 2013

Presence And Function Of Tetrodotoxin In Terrestrial Vertebrates And Invertebrates, Amber N. Stokes

All Graduate Theses and Dissertations

Tetrodotoxin (TTX) is a potent neurotoxin that acts by blocking the pore region of voltage-gated sodium channels in nerve and muscle tissue. This causes paralysis, and often death due to asphyxiation. Interestingly, TTX is found in an array of organisms ranging from bacterial species to vertebrates. Further, TTX is found in both aquatic and terrestrial environments. This range of taxa and environments has led to three common lines of study for ecological research on this toxin: production, predation, and identification of novel TTX bearing taxa. I began my research by also refining a Competitive Inhibition Enzymatic Immunoassay technique for fast ...


The Distribution Of Fruit And Seed Toxicity During Development For Eleven Neotropical Trees And Vines, Noelle G. Beckman Jul 2013

The Distribution Of Fruit And Seed Toxicity During Development For Eleven Neotropical Trees And Vines, Noelle G. Beckman

Biology Faculty Publications

Secondary compounds in fruit mediate interactions with natural enemies and seed dispersers, influencing plant survival and species distributions. The functions of secondary metabolites in plant defenses have been well-studied in green tissues, but not in reproductive structures of plants. In this study, the distribution of toxicity within plants was quantified and its influence on seed survival was determined in Central Panama. To investigate patterns of allocation to chemical defenses and shifts in allocation with fruit development, I quantified variation in toxicity between immature and mature fruit and between the seed and pericarp for eleven species. Toxicity of seed and pericarp ...


Climate Change And Plant Demography In The Sagebrush Steppe, Aldo Compagnoni Jul 2013

Climate Change And Plant Demography In The Sagebrush Steppe, Aldo Compagnoni

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


Local And Regional Drivers Of Biodiversity: From Life-History Traits To System-Level Properties, Sarah R. Supp May 2013

Local And Regional Drivers Of Biodiversity: From Life-History Traits To System-Level Properties, Sarah R. Supp

All Graduate Theses and Dissertations

Biodiversity research aims to understand and predict the occurrence, abundance, and distribution of species and the diversity of species traits, body sizes, and functional roles in a community. Ecologists lack a comprehensive understanding of the interplay between processes driving biodiversity at differing spatiotemporal scales, hindering the ability to predict response to change. A crucial challenge facing ecologists is to incorporate knowledge of the regional dynamics and temporal stability of communities in biodiversity research. This dissertation investigates the role that species traits and system-level properties play in determining biodiversity at local sites and evaluates biodiversity response to change.

Local and regional ...


Fatty Acid Induced Insulin Resistance In The Brain, Hyoung Il Oh May 2013

Fatty Acid Induced Insulin Resistance In The Brain, Hyoung Il Oh

All Graduate Theses and Dissertations

The prevalence of obesity, which is considered as a disease, has been increasing uncontrollably over the last two decades. Obesity is a state of disregulated energy homeostasis characterized by hypothalamic resistance to adiposity signals (insulin and leptin). While many factors are involved in the development of obesity, excess dietary fat has been proposed as one of the main causal factors. This causes disrupted energy homeostasis by inducing both leptin and insulin resistance in the central nervous system. Although brain tissue was considered to be insulin independent for a long time, insulin is now recognized to have important functions in the ...


Apoptotic And Epigenetic Induction Of Embryo Failure Following Somatic Cell Nuclear Transfer, Aaron Patrick Davis May 2013

Apoptotic And Epigenetic Induction Of Embryo Failure Following Somatic Cell Nuclear Transfer, Aaron Patrick Davis

All Graduate Theses and Dissertations

Somatic cell nuclear transfer (SCNT) is a useful tool for selective breeding, conservation, and production of transgenic animals. Despite the successful cloning of several species, high rates of embryo failure following SCNT prevent the wide-scale use of the technique. Embryos produced through cloning have a higher incidence of developmental arrest, decreased developmental potential, frequent implantation failures, and increased incidence of abortion. The objective of this dissertation research was to characterize the factors that lead to SCNT failures by examining epigenetic and apoptotic pathways that can negatively influence the development of cloned preimplantation embryos. Aberrant genome reprogramming is generally considered to ...


A Data-Intensive Assessment Of The Species Abundance Distribution, Elita Baldridge May 2013

A Data-Intensive Assessment Of The Species Abundance Distribution, Elita Baldridge

All Graduate Theses and Dissertations

The hollow curve species abundance distribution describes the pattern of large numbers of rare species and a small number of common species in a community. The species abundance distribution is one of the most ubiquitous patterns in nature and many models have been proposed to explain the mechanisms that generate this pattern. While there have been numerous comparisons of species abundance distribution models, most of these comparisons only use a small subset of available models, focus on a single ecosystem or taxonomic group, and fail to use the most appropriate statistical methods. This makes it difficult to draw general conclusions ...


Evaluating Eriogonum Corymbosum Tolerance To Frequent Irrigation And Evaluating Its Significant Morphological Variations For Potential Cultivars, Graham C. Hunter May 2013

Evaluating Eriogonum Corymbosum Tolerance To Frequent Irrigation And Evaluating Its Significant Morphological Variations For Potential Cultivars, Graham C. Hunter

All Graduate Theses and Dissertations

Two separate experiments were designed to assess the value of Lacy Buckwheat (Eriogonum corymbosum ) as a low water landscape plant. Low water use landscapes can contribute to water conservation in arid climates. Developing a palette of plants that are both attractive and drought tolerant can promote the acceptance of low water use landscapes as an alternative to the traditional bluegrass landscapes of the Intermountain West. Eriogonum corymbosum is an attractive subshrub species native to low rainfall areas of the Colorado Plateau. A strip plot design containing four repetitions with four randomly assigned plants each of Eriogonum corymbosum , Eriogonum thompsoniaeand the ...


Reproductive Biology And Impacts Of Energy Development On Physaria Congesta And Physaria Obcordata (Brassicaceae), Two Rare And Threatened Plants In The Piceance Basin, Colorado, Sarah Lynn Clark May 2013

Reproductive Biology And Impacts Of Energy Development On Physaria Congesta And Physaria Obcordata (Brassicaceae), Two Rare And Threatened Plants In The Piceance Basin, Colorado, Sarah Lynn Clark

All Graduate Theses and Dissertations

The Piceance Basin in western Colorado has undergone a drastic increase in oil and gas development over the last two decades. This increase has escalated concerns about the effects of development on the Basin’s flora and fauna, especially the rare plant community. Potential impacts from oil and gas development on rare plants may be found through decrease in plant habitat or by a decrease in plant reproductive success through changes to important pollinator communities. Here, we observed the pollinator community on two rare mustard plants, Physaria congesta and Physaria obcordata (Brassicaceae), both listed as threatened by the US Fish ...


Winter Ecology Of Waterfowl On The Great Salt Lake, Utah, Josh L. Vest May 2013

Winter Ecology Of Waterfowl On The Great Salt Lake, Utah, Josh L. Vest

All Graduate Theses and Dissertations

I designed a suite of studies in coordination with Utah Division of Wildlife Resources (UDWR) to evaluate waterfowl use of the GSL in winter and ecological aspects associated with GSL use. These studies provided insight into key information gaps previously identified by UDWR regarding management of GSL resources. Population surveys indicated total duck abundance was low when GSL surface elevations were low and wetland resources diminished because of persistent drought in the system. Also, ducks appear to use hypersaline parts of GSL more when freshwater habitats are limited from either drought or ice conditions. Common goldeneye, northern shoveler, and green-winged ...


Novel Aminoglycosides: Bioactive Properties And Mechanism Of Action, Sanjib K. Shrestha May 2013

Novel Aminoglycosides: Bioactive Properties And Mechanism Of Action, Sanjib K. Shrestha

All Graduate Theses and Dissertations

Fungicide discovery is relatively neglected when compared to the investment in the development of antibacterial, antiviral, and anti-cancer therapeutics. Due to extensive use of currently available fungicides in agriculture and medicine, resistance is emerging among plant and animal pathogenic fungi. This necessitates the search for novel antifungal agents that are effective and less toxic and that do not promote resistance.

FG08 and K20 are novel aminoglycoside analogs synthesized from kanamycin B and A, respectively. The antimicrobial properties of these analogs were tested in vitro against a wide range of agriculturally and clinically important fungal pathogens. Both compounds showed broad-spectrum antifungal ...


An Environmental History Of The Bear River Range, 1860-1910, Bradley Paul Hansen May 2013

An Environmental History Of The Bear River Range, 1860-1910, Bradley Paul Hansen

All Graduate Theses and Dissertations

The study of environmental history suggests that nature and culture change all the time, but that the rate and scale of such change can vary enormously. During the late 19th and early 20th centuries, Anglo settlement in the American West transformed landscapes and ecologies, creating new and complex environmental problems. This transformation was particularly impressive in Cache Valley, Utah's Bear River Range. From 1860 to 1910, Mormon settlers overused or misused the Bear River Range's lumber, grazing forage, wild game, and water resources and introduced invasive plant and animal species throughout the area. By the turn of the ...


Kisspeptins - Expression, Purification, And Biological Assays, Mathew Puthayathu Kurian May 2013

Kisspeptins - Expression, Purification, And Biological Assays, Mathew Puthayathu Kurian

All Graduate Theses and Dissertations

Kisspeptins are an arginine-phenylalanine-amide family of neuroactive peptide hormones encoded by the KISS1 gene, which, along with its receptor GPR54, are essential for the initiation of puberty in adolescents and maintenance of reproductive function in adults. Kisspeptins are also involved in the sexual dimorphism of the brain. Kisspeptin signaling defects are implicated in reproductive disorders like idiopathic hypogonadotropic hypogonadism, precocious puberty and polycystic ovarian syndrome. Kisspeptins were originally discovered as metastasis suppressors in melanoma cell lines and have also been found to down regulate metastasis in breast and ovarian cancers. They have been found to inhibit the colonization of secondary ...


Study Of Genes Relating To Degradation Of Aromatic Compounds And Carbon Metabolism In Mycobacterium Sp. Strain Kms, Chun Zhang May 2013

Study Of Genes Relating To Degradation Of Aromatic Compounds And Carbon Metabolism In Mycobacterium Sp. Strain Kms, Chun Zhang

All Graduate Theses and Dissertations

Polycyclic aromatic hydrocarbons, produced by anthropological and natural activities, are hazardous through formation of oxidative radicals and DNA adducts. Growth of Mycobacterium sp. strain KMS, isolated from a contaminated soil, on the model hydrocarbon pyrene induced specific proteins. My work extends the study of isolate KMS to the gene level to understand the pathways and regulation of pyrene utilization. Genes encoding pyrene-induced proteins were clustered on a 72 kb section on the KMS chromosome but some also were duplicated on plasmids. Skewed GC content and presence of integrase and transposase genes suggested horizontal transfer of pyrene-degrading gene islands that also ...


Synthetic Piriform Spider Silk Protein Production, Jordan Ballam, Cole Peterson Jan 2013

Synthetic Piriform Spider Silk Protein Production, Jordan Ballam, Cole Peterson

Biology Posters

No abstract provided.


Determination Of Female Mate Selection In Guppies Based On Male Color Versus Length, Lauren Mcmillan, Sydney Olson, Kim Rawlins, Jacob Stewart, Ariel Tayson Jan 2013

Determination Of Female Mate Selection In Guppies Based On Male Color Versus Length, Lauren Mcmillan, Sydney Olson, Kim Rawlins, Jacob Stewart, Ariel Tayson

Biology Posters

No abstract provided.


In The News, Joe N. Caudell Jan 2013

In The News, Joe N. Caudell

Human–Wildlife Interactions

No abstract provided.


A Novel Sodium Channel In The Mammalian Taste System, Melissa N. Fillmore Jan 2013

A Novel Sodium Channel In The Mammalian Taste System, Melissa N. Fillmore

Biology Posters

Salty taste, one of the five taste qualities recognized in the mammalian peripheral gustatory system is thought to be mediated by an ion channel receptor. The epithelial sodium channel, ENaC, is thought to be the channel for salt taste transduction. ENaC is crucial in regulating salt reabsorption, helps control overall salt and water homeostasis in an organism, and contributes to blood pressure. While ENaC plays an important role in salt taste perception, it is responsible for only part of the total sodium transduction pathway in humans, suggesting that there may be another component in the salt transduction mechanism. We have ...


Teaching The Teachers: Creating Learning Modules For Presentations At The Willow Park Zoo, Erica Littledike Jan 2013

Teaching The Teachers: Creating Learning Modules For Presentations At The Willow Park Zoo, Erica Littledike

Biology Posters

No abstract provided.


Temperature Effects On Cutaneous Healing In Rough-Skinned Newts (Taricha Granulosa), Sydney Greenfield, Geoff Smith, Lori Neuman-Lee, Susannah French Jan 2013

Temperature Effects On Cutaneous Healing In Rough-Skinned Newts (Taricha Granulosa), Sydney Greenfield, Geoff Smith, Lori Neuman-Lee, Susannah French

Biology Posters

No abstract provided.


Interactive Signage At The Willow Park Zoo, Haley Duston Jan 2013

Interactive Signage At The Willow Park Zoo, Haley Duston

Biology Posters

No abstract provided.


Village Weavers, Ploceus Cucullatus: It Takes A Village To Weave A Nest, Eliza Browning Jan 2013

Village Weavers, Ploceus Cucullatus: It Takes A Village To Weave A Nest, Eliza Browning

Biology Posters

No abstract provided.


Phylogenetic Placement Of The Genus Tricholosporum By Dna Sequencing, Katelyn Heaton Jan 2013

Phylogenetic Placement Of The Genus Tricholosporum By Dna Sequencing, Katelyn Heaton

Biology Posters

No abstract provided.


Kids, Zoo Animals, And Education, Michelle Shook Jan 2013

Kids, Zoo Animals, And Education, Michelle Shook

Biology Posters

No abstract provided.


Parallel Evolution In The Northern Scorpion Paruroctus Boreus, Zachary J. Valois Jan 2013

Parallel Evolution In The Northern Scorpion Paruroctus Boreus, Zachary J. Valois

Biology Posters

No abstract provided.


Effects Of Glutamine Synthetase On Indigoidine Production In Escherichia Coli, David Gage, Fuchao Xu, Dayu Yu, Jixun Zhan Jan 2013

Effects Of Glutamine Synthetase On Indigoidine Production In Escherichia Coli, David Gage, Fuchao Xu, Dayu Yu, Jixun Zhan

Biology Posters

No abstract provided.


Comparison Between The Effects Of Size And Color In Mate Choice Among Guppies, Makda Gebre Jan 2013

Comparison Between The Effects Of Size And Color In Mate Choice Among Guppies, Makda Gebre

Biology Posters

No abstract provided.