Life Sciences Commons^™

Effect Of Reproductive Efficiency In Regards To Workload On Peripheral Circulations Of Blood Cortisol And Leptin In The Open Mare, Michaelle K. Coker

Electronic Theses and Dissertations

ABSTRACT

Effect of Reproductive Efficiency in Regards to Workload on Peripheral Circulations of Blood Cortisol and Leptin in the Open Mare

(December, 2016)

Michaelle Kathleen Coker, B.S., Texas A&M University

Thesis Director: Dr. John Michael Mehaffey

Quarter and Paint horse mares (n= 9) were randomly assigned to 1 of 3 groups after being blocked based by expected conception date. Groups consist of mares on no work (NW), light work (LW), and moderate work (MW). Blood was taken weekly via jugular venipuncture prior to first heat cycle from each mare. Additionally, blood was taken at time of ovulation and then weekly …

An Analysis Of Gulf Of Maine Cod Metapopulation Structure And Localized Stability, With Application To Area-Based Fisheries Management, Derek Olson

Electronic Theses and Dissertations

The complex metapopulation structure of groundfish stocks in the Gulf of Maine, particularly Atlantic cod (Gadus morhua), is largely ignored under the current system of broad-scale stock assessment and management. This mismatch of biological and administrative scales has contributed to severe overall stock decline and localized serial depletion of Gulf of Maine cod. Such chronic management failure has led to growing calls for a more area-based, finer-scale approach to managing groundfish in the Gulf of Maine. A primary difficulty hindering the development of finer-scale groundfish management has been the challenge of estimating fishing mortality upon local stock components. …

The Forgotten Cousin In Freshwater Community Ecology: Tidal Freshwater Wetlands, Jack R. Mclachlan

Electronic Theses and Dissertations

Tidal freshwaters are unique in their placement in the landscape, forming where freshwater riverine flows are sufficient to overwhelm the saline water of the incoming tide, but not strong enough to suppress tidal water-height fluctuations. Tidal freshwaters and their wetlands have been overlooked by freshwater and marine researchers alike; neither discipline considers tidal freshwaters to fall under their purview. Invertebrate communities in tidal freshwaters are thought to be species depauperate; the consensus is that they support fewer taxa than nearby non-tidal freshwaters, but little is known about how these communities are structured. This study investigated how tidal hydrology, an atypical …

Roles Of Siphon Flows In Suspension Feeding, Kevin Du Clos

Electronic Theses and Dissertations

Benthic marine suspension feeders provide an important link between benthic and pelagic ecosystems. The strength of this link is determined by suspension-feeding rates. Many studies have measured suspension-feeding rates using indirect clearance-rate methods, which are based on the depletion of suspended particles. Direct methods that measure the flow of water itself are less common, but they can be more broadly applied because clearance-rate measurements are affected by properties of the cleared particles. We present pumping rates for three species of suspension feeders, the clams Mya arenaria and Mercenaria mercenaria and the tunicate Ciona intestinalis, calculated using a direct method …

The Influence Of The Invasive Chinese Tallow (Triadica Sebifera) Leaf Litter On Aquatic Chemistry And Microbial Community Composition, Raymond D. Montez

Electronic Theses and Dissertations

Global climate change and anthropogenic activity have facilitated the movement and invasive potential of nonnative plants in native environments. These invasions can have negative effects on ecosystem diversity and function. The nonnative and invasive plant, Chinese Tallow (Triadica sebifera), has already invaded much of the south eastern US where it is outcompeting native tree species and changing ecosystem diversity in a variety of habitats. Leaf litter from the Chinese tallow has been shown cause changes in dissolved oxygen and pH in the aquatic environment. Turbidity is also affected when Chinese tallow litter is present in water. A series of …

Chemical And Non-Chemical Control Of Potato Pink Rot, Xuemei (Missi) Zhang

Electronic Theses and Dissertations

Pink rot of potato (Solanum tuberosum) is a widespread soilborne disease that causes significant losses in the field and storage. It is caused by Phytophthora erythroseptica (Pethybr.), an oomycete pathogen that produces sexual spores that can survive in soil for years. The management of pink rot mainly relies on chemical control. However, the most effective chemical in pink rot control, mefenoxam, is losing its efficacy owing to the development of mefenoxam resistance in P. erythroseptica. To evaluate alternative fungicides (including chemical and biological fungicides) to mefenoxam in pink rot control, two greenhouse experiments and three field trials …

Investigating The Relationship Among Sleep, Stress, And Body Mass Index In At-Risk First-Year College Students, Grace A. Violette

Electronic Theses and Dissertations

The study objective was to investigate relationships among body mass index (BMI), sleep quality/duration, and perceived stress in 1,176 first semester college students who enrolled in Get Fruved, an 8-state social marketing intervention to prevent unwanted weight gain. Research was limited to first-year college students at-risk for unwanted weight gain. Eligibility was based on self-report of inadequate fruit and vegetable intake and subjects meeting one or more health-risk criteria (e.g., high BMI). Students (mean age=181 years; 65% white) completed physical measurements and an online survey, including the Pittsburgh Sleep Quality Index (PSQI) (score range 0-21; ˃5=disordered sleep) and the Cohen …

Structural And Functional Analysis Of Grapefruit Flavonol-Specific-3-O-Gt Mutant P145t, Sangam Kandel Mr

Electronic Theses and Dissertations

This research is focused on the study of the effect of mutating proline 145 to threonine on the substrate and regiospecificity of flavonol specific 3-O-glucosyltransferase (Cp3GT). While the mutant P145T enzyme did not glucosylate anthocyanidins, it did glucosylate flavanones and flavones in addition to retaining activity with flavonols. HPLC was used for product identification and showed mutant P145T glucosylated naringenin at the 7-OH position forming naringenin-7-O-glucoside and flavonols at the 3-OH position. Homology modeling and docking was done to predict the acceptor substrate recognition pattern and models were validated by experimental results. In other related work, …

Pharmacokinetics, Tissue Distribution, Synergistic Activity, And Antitumor Activity Of Two Isomeric Flavones, Crystal L. Whitted

Electronic Theses and Dissertations

Flavonoids are polyphenolic secondary metabolites found in plants that have bioactive properties including antiviral, antioxidant, and anticancer. Two isomeric flavone were extracted from Gnaphalium elegans and Achyrocline bogotensis, plants used by the people from the Andean region of South America as remedies for cancer. 5,7-dihydroxy-3,6,8-trimethoxy-2-phenyl-4H-chromen-4-one (5, 7–dihydroxy- 3, 6, 8 trimethoxy flavone/ flavone A) and 3,5-dihydroxy-6,7,8-trimethoxy-2-phenyl-4H-chromen-4-one (3, 5–dihydroxy-6, 7, 8–trimethoxy flavone/ flavone B) have shown antineoplastic activity against colon cancer cell lines dependent upon their differentiation status. Pharmacokinetic studies reported herein were used to determine dosing for antitumor assays, as well as determine target tissue concentration. These included the …

Environmental Dna Detection Of Invasive Species, Geneva York

Electronic Theses and Dissertations

Invasive species cause catastrophic changes to environments they are introduced into. Early detection offers the best chance at controlling the spread and mitigating any potential damages caused by the invaders. Environmental DNA (eDNA) has emerged as a more sensitive and cost effective alternative to traditional survey approaches to detection. In this study, I designed primer-probe sets for use in quantitative PCR detection of three invasive Centrarchid species, Largemouth Bass (Micropterus salmoides), Smallmouth Bass (Micropterus dolomieu) and Black Crappie (Pomoxis nigromaculatus). I surveyed 21 water bodies in Maine during two seasons (winter and spring). I …

Identification And Characterization Of Genes Involved In Metabolism Of N5 Monoene Precursors To N5 Anacardic Acids In The Trichomes Of Pelargonium X Hortorum., Richa A. Singhal

Electronic Theses and Dissertations

Unusual monoenoic fatty acids (UMFA’s) and specialized metabolites called anacardic acids (AnAc) are produced in glandular trichomes of Pelargonium ´ hortorum (geranium). The UMFA’s, 16:1^∆11 and 18:1^∆13 are precursors for the synthesis of unsaturated AnAc 22:1n5and 24:1n5 that contribute to pest resistance in geraniums. UMFAs and their derived AnAc metabolites not only provide a useful biological marker that differentiates the biosynthetic pathway for unusual mononenes from the common fatty acids (i.e. stearic, palmitic, oleic, linoleic and linolenic) but also have industrial, medical and agricultural applications. Fatty acid biosynthesis enzymes like acyl carrier proteins (ACPs); thioesterases (TEs) and β-ketoacyl-ACP …

Identification Of Residual Descending Pathways After Human Spinal Cord Injury., Darryn A. Atkinson

Electronic Theses and Dissertations

Spinal Cord Injury (SCI) in humans is a heterogeneous diagnosis, resulting in variable paralysis and paresthesia based on the mechanism, rostro-caudal location, and severity of injury. Both neurophysiological and anatomical studies have suggested that subclinical residual supraspinal-spinal connectivity exists in a subset of individuals deemed to have motor and sensory complete injuries. Recent reports of volitional movement in chronic, motor complete individuals during epidural spinal stimulation have provided compelling evidence that these residual projections may be capable of mediating volitional movement when the functional state of spinal circuitry is electrically modulated. It was the goal of this project to identify …

Determining Public Perceptions Toward Wildland Fire In The Veluwe Region Of The Netherlands, Amy Brennan

Electronic Theses and Dissertations

The Netherlands has been facing a growing threat of wildfires due to warmer

and drier weather patterns. The purpose of this study was to identify public

perceptions toward wildland fire in the forested Veluwe region of the country. The

Dutch have little experience with wildland fires or fire as a management tool. In a

collaborative effort between Stephen F. Austin State University and the Instituut

Fysieke Veiligheid, the Dutch public safety agency, a survey was distributed to

residents and visitors to the Veluwe to reveal and quantify public opinions and

perceptions regarding wildland fire and public expectations of government

agencies …

Preparing For Effective Program Dissemination And Implementation: An Analysis Of Problems And Proposals For The Icook 4-H Program, Jodi L. Randall

Electronic Theses and Dissertations

While much effort has gone into the creation of obesity prevention programs like iCook 4-H, such programs remain largely under-utilized. The disconnect between research and practice highlights the necessity of dissemination and implementation strategies to ensure programs become adopted into practice. Creating a well-informed systematic approach to implementation will ensure that the iCook 4-H program will be implemented efficaciously and sustainably to improve the health of generations to come. The goal of this research was to implement the pilot dissemination and describe the findings in the context of the Quality Implementation Framework. The objectives were to report outcomes of the …

Investigating High Speed Localization Microscopy Through Experimental Methods, Data Processing Methods, And Applications Of Localization Microscopy To Biological Questions, Andrew J. Nelson

Electronic Theses and Dissertations

Fluorescence Photoactivation Localization Microscopy(FPALM) and other super resolution localization microscopy techniques can resolve structures with nanoscale resolution. Unlike techniques of electron microscopy, they are also compatible with live cell and live animal studies, making FPALM and related techniques ideal for answering questions about the dynamic nature of molecular biology in living systems. Many processes in biology occur on rapid sub second time scales requiring the imaging technique to be capable of resolving these processes not just with a high enough spatial resolution, but with an appropriate temporal resolution. To that end, this Dissertation in part investigates high speed FPALM as …

Retinoic Acid Signaling Regulates Krt5 Independently Of Stem Cell Markers In Submandibular Salivary Gland Epithelium., Timur Maratovich Abashev

Electronic Theses and Dissertations

Vitamin A metabolism, which produces the signaling molecule Retinoic Acid (RA), has been demonstrated to be important for growth and branching morphogenesis of mammalian embryonic salivary gland epithelium. However, it is not known whether RA functions directly within epithelial cells or in associated tissues that influence morphogenesis of salivary epithelium. Moreover, downstream targets of RA transcriptional regulation have not been identified. Here we show that canonical RA signaling occurs in multiple tissues of embryonic mouse salivary glands, including epithelium, associated parasympathetic ganglion neurons, and non‑neuronal mesenchyme. By culturing epithelium explants in isolation from other tissues we demonstrate that RA influences …

Examination Of The Relevance Of Pi3k And Pten Pathway In Ustilago Maydis., Nathaniel Edward Dalton

Electronic Theses and Dissertations

Ustilago maydis is a fungal pathogen that is an obligate parasite on Zea mays (Corn) in order to undergo and complete its sexual life cycle. The cells grow as a haploid form until they meet a compatible partner and undergo a dimorphic switch from a budding yeast-like cell type to a filamentous dikaryon. Infection of the host plant is characterized by leaf chlorosis, anthocyanin content, and formation of large galls that develop on the stem, leaves, cobs, and flowers. Many signaling cascades such as MAPK and PKA are involved in the regulation of the infection lifecycle. The Phosphatidylinosotiol 3 Kinase/ …

Approaches To Arthropod Conservation : Landscape Genetics, Community Assessment, And Prediction Of Extinction Risk., Victoria Annette Prescott

Electronic Theses and Dissertations

Although urbanization is a leading cause of species extinction throughout the world, the impact of urban development on arthropods is little studied and, as a result, poorly understood. I used three distinct approaches to studying arthropod conservation in North America. First, I used landscape genetics techniques to study the impact of urbanization on gene flow among populations of Rabidosa rabida, the rabid wolf spider. While gene flow was not detrimentally reduced, urban development correlated with a reduction in migration rates among populations, and to my knowledge, this is the first study to document isolation by resistance in spiders. Next, …

Spreading Speeds Along Shifting Resource Gradients In Reaction-Diffusion Models And Lattice Differential Equations., Jin Shang

Electronic Theses and Dissertations

A reaction-diffusion model and a lattice differential equation are introduced to describe the persistence and spread of a species along a shifting habitat gradient. The species is assumed to grow everywhere in space and its growth rate is assumed to be monotone and positive along the habitat region. We show that the persistence and spreading dynamics of a species are dependent on the speed of the shifting edge of the favorable habitat, c, as well as c^*(∞) and c^*(−∞), which are formulated in terms of the dispersal kernel and species growth rates in both directions. When …

Using A Mouse Model To Investigate Male Bias In Autism Spectrum Disorder Incidence., Elizabeth Ann Gordon

Electronic Theses and Dissertations

The review (Chapter 1) overviews our current understanding of the sex bias in autism spectrum disorders (ASD), whereby males are 4 times more likely to develop the condition. The longstanding uncertainty surrounding the etiology of autism can be informed by inclusion of both sexes in future research to better understand the mechanism responsible for this sex bias. Both clinical studies and animal models are useful tools to elucidate the underlying cause(s) of sexual dimorphic morphological, physiological, and behavioral differences in the ASD phenotype. Sex differences in social behaviors are common across species, underscoring the importance of assessing baseline sex differences …

Dietary Resource Utilization Patterns And Head Morphology Among Three Sympatric Watersnake Species., Micah Warren Perkins

Electronic Theses and Dissertations

The coexistence of similar species may be related to a variety of resource utilization differences. Dietary resource utilization variation may be the most important difference allowing for the coexistence of sympatric snake species. Many watersnakes (Nerodia spp.) live in sympatry and use similar aquatic habitats feeding on similar prey. While these sympatric watersnakes may have different general foraging patterns, snake diet may be affected by a variety of factors. Therefore, I initiated an investigation to understand the coexistence of sympatric plain-bellied (N. erythrogaster), diamondback (N. rhombifer) and northern (N. sipedon) watersnakes by addressing …

Plant Community Responses To The Removal Of Lonicera Maackii From An Urban Woodland Park., Elihu H. Levine

Electronic Theses and Dissertations

Impacts of Lonicera maackii on native forest communities have been widely researched, but long-term responses of plant communities to the removal of this exotic shrub have not been extensively evaluated. The Louisville Olmsted Parks Conservancy removes exotic shrubs and vines to restore ecological processes and native species in the woodlands of Cherokee Park. Paired-plots were established in 2008 to gather baseline herb, vine, tree, and shrub community data. Honeysuckle was removed from one plot of each pair in 2009 and community data were gathered again in 2013. Native herb cover and richness, vine cover, and tree sapling abundance increased where …

Tnf-Like Weak Inducer Of Apoptosis (Tweak) : Not So Weak After All., Joseph Dekward Mcmillan Iv

Electronic Theses and Dissertations

Background: Tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) is a proinflammatory cytokine belonging to the TNF super family. TWEAK produces a variety of cellular responses through the binding to fibroblast growth factor inducible 14 (Fn14), a member of TNF receptor superfamily. Although Fn14 lacks a death domain, TWEAK has been found to induce apoptosis in some cell types by perturbing the activity of certain pathways such as TNF-receptor signaling. TWEAK is also known to regulate proliferation and differentiation of myogenic cells. We have previously reported that the TWEAK-Fn14 system causes skeletal muscle wasting both in vitro and in …

Old-Growth Characteristics Of Northern White-Cedar Stands, Nathan Wesely

Electronic Theses and Dissertations

Northern white-cedar (Thuja occidentalis; hereafter white-cedar) communities have received relatively little research attention, and managers lack the tools used in the management of other commercial tree species. This includes the recognition of old-growth characteristics and the differentiation between old-growth and partially harvested stands, particularly in the context of Forest Stewardship Council (FSC-US) certification. Specifically, there is very little information about characteristics that define old-growth white-cedar stands despite the species’ abundance and wide distribution. Regional indices for late-successional or old-growth stands (Whitman and Hagan, 2007) do not include white-cedar. Forests dominated by white-cedar represent a type that currently lacks …

Hydroacoustic Analysis Of The Effects Of A Tidal Power Turbine On Fishes, Haley Viehman

Electronic Theses and Dissertations

Tidal currents help shape coastal marine environments and are essential in life cycles of many fish species. Areas with strong tidal currents are also targeted by humans for energy extraction via tidal energy turbines. The effects of these devices on fishes are difficult to predict because fish behavior within fast tidal currents is largely unstudied. Based at a tidal energy site in Cobscook Bay, Maine, this work sought to describe fish reactions to a tidal energy device, to understand the natural presence of fish at the site, and to provide guidance for future monitoring of tidal energy device effects in …

Modeling And Forecasting The Influence Of Current And Future Climate On Eastern North American Spruce-Fir (Picea-Abies) Forests, Caitlin Andrews

Electronic Theses and Dissertations

The spruce-fir (Picea-Abies) forest type of the Acadian Region is at risk of disappearing from the United States and parts of Canada due to climate change and associated impacts. Managing for the ecosystem services provided by this forest type requires accurate forecasting of forest metrics across this broad international region in the face of the expected redistribution of tree species. This analysis linked species specific data with climate and topographic variables using the nonparametric random forest algorithm, to generate models that accurately predicted changes in species distribution due to climate change. A comprehensive dataset, consisting of 10,493,619 observations …

Transient Receptor Potential Cation Channel, Subfamilies V, Member 1 (Trpv1) And M, Member 1 (Trpm1) Contribute To Neural Signaling In Mouse Retina., Jennifer Noel

Electronic Theses and Dissertations

The retina processes light information through parallel pathways in order to extract and encode the visual scene. Light information is transmitted to the brain through approximately 30 ganglion cells (GCs), the retinal output neurons. Trp channels modulate the responses of retinal neurons within specific pathways. The study of the expression and function of the majority of Trp channels in the retina is largely in its infancy. My dissertation first investigated the expression and function of the transient receptor potential vanilloid-1 (TRPV1) receptor/channel in the retina. TRPV1, the first cloned and most highly studied Trp channel in the peripheral nervous system, …

Glutathione S-Transferase P In Glucose Homeostasis In Mice., Shubha Ghosh Dastidar

Electronic Theses and Dissertations

High calorie diets have fostered the current pandemic of obesity and comorbid conditions of non-alcoholic fatty liver disease (NAFLD), systemic insulin resistance (IR) and type 2 diabetes (T2D). Hepatic glutathione S-transferases (GSTs) are dysregulated in obesity, NAFLD and diabetes. The multifunctional GST pi isoform (GSTP) catalyzes acrolein metabolism and inhibits JNK (c-Jun NH₂-terminal kinase). The purpose of this study was to test specifically whether GSTP deficiency disturbs glucose homeostasis in mice. Hepatic GST proteins were downregulated by short-term high fat diet (HFD) in wild type (WT) mice concomitant with glucose intolerance, increased hepatic JNK activation and protein-acrolein …

A Novel Role Of Human Dna Damage Checkpoint Protein Atr In Suppressing Ca2+ Overload-Induced Parp1-Mediated Necrosis, Hui Wang-Heaton

Electronic Theses and Dissertations

Ataxia telangiectasia and Rad3-related (ATR) is well known for its regulatory role in DNA damage responses (DDR) as a checkpoint kinase that phosphorylates hundreds of protein substrates. However, its role in cellular non-DNA damage stress responses (NDDR) is unknown. Necrosis is one form of cell death and traditionally has been regarded as a passive and uncontrolled cell death. Recently, evidence has emerged to support the concept that necrosis also may occur in a programmed manner and that PARP1 can be a mediator. Active poly (ADP-ribose) polymerase 1 (PARP1) hydrolyzes nicotinamide adenine dinucleotide (NAD⁺) to produce poly (ADP-ribose) (PAR) …

Linking Rising Pco2 And Temperature To The Larval Development, Physiology And Gene Expression Of The American Lobster (Homarus Americanus), Jesica Waller

Electronic Theses and Dissertations

Anthropogenic warming and ocean acidification are occurring as CO₂ continues to accumulate in the atmosphere (OA). Few studies have evaluated the joint effects of elevated temperature and partial pressure of CO₂ (pCO₂)on marine organisms. In this study we investigated the interactive effects of Intergovernmental Panel on Climate Change (IPCC) predicted temperature and pCO₂ for the end of the 21st century on key aspects of larval development of the American lobster, Homarus americanus, an otherwise well-studied, iconic, and commercially prominent species in the northeastern United States and Atlantic Canada. Our experiments showed …