UNT Libraries - 622 Matching Results

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open access

Evaluating the Role of UV Exposure and Recovery Regimes in PAH Photo-Induced Toxicity to Daphina Magna

Description: Polyaromatic hydrocarbons (PAHs) are contaminants synthesized through incomplete combustion of carbon based substances. PAHs are known to be photodynamic and toxicity increases exponentially when in contact with ultraviolet radiation (UV). The effect of UV absent recovery periods and potential for latent toxicity during photo-induced toxicity are previously unknown and are not included within the toxicity model. Results of equal interval tests further support the current reciprocity model as a … more
Date: August 2017
Creator: Gnau, Jennifer Leigh
Item Type: Refine your search to only Thesis or Dissertation
open access

Generating Molecular Biology Tools to Investigate the Ca2+ Binding Ability of Arabidopsis TON2

Description: The position of the cell division plane in plants is determined by the position of the preprophase band. The pre prophase band (PPB) is a ring of microtubules centered around the nucleus on the inner side of plasma membrane that establishes the cortical division site. The PPB forms at the end of G2 and breaks down at the end of prophase leaving behind protein markers of its position that are collectively called the cortical division site. During cytokinesis the phragmoplast expands towards the … more
Date: August 2017
Creator: Shao, Danyang
Item Type: Refine your search to only Thesis or Dissertation
open access

Investigating Human Gut Microbiome in Obesity with Machine Learning Methods

Description: Obesity is a common disease among all ages that has threatened human health and has become a global concern. Gut microbiota can affect human metabolism and thus may modulate obesity. Certain mixes of gut microbiota can protect the host to be healthy or predispose the host to obesity. Modern next-generation sequencing technique allows accessing huge amount of genetic information underlying microbiota and thus provides new insights into the functionality of these micro-organisms and their interac… more
Date: August 2017
Creator: Zhong, Yuqing
Item Type: Refine your search to only Thesis or Dissertation
open access

Neurological Responses to a Glucose Diet in Caenorhabditis elegans

Description: TRPV channels play a role in both mammalian insulin signaling, with TRPV1 expression in pancreatic beta-cells, and in C. elegans insulin-like signaling through expression of OSM-9, OCR-1, and OCR-2 in stress response pathways. In response to a glucose-supplemented diet, C. elegans are know to have sensitivity to anoxic stress, exhibit chemotaxis attraction, and display reduced egg-laying rate. Transcriptome analysis reveals that glucose stimulates nervous system activity with increased transcri… more
Date: August 2017
Creator: Dumesnil, Dennis
Item Type: Refine your search to only Thesis or Dissertation
open access

Respiratory Responses in the Freshwater Snail (Pomacea Bridgesii) are Differently Affected by Temperature, Body Mass,and Oxygen Availability

Description: Pomacea bridgesii is a snail species native to tropical and sub-tropical regions, where it usually faces variability in water, temperature and oxygen level. This study of the effect of temperature on mass-specific oxygen consumption (ṀO2) and its relation to body weight shows that the ṀO2 of juvenile snails in normoxia (18-21 kPa) acclimated at temperature of 25°C ranged from 5 to 58 µMol O2/g/h, with a mean of 41.4 ± 18.3 µMol O2/g/h (n=7). Adult snails in normoxia at 25°C show less variat… more
Date: August 2016
Creator: Frifer, Wenasa Salem
Item Type: Refine your search to only Thesis or Dissertation
open access

The Effect of Post-exercise Ethanol Consumption on the Acute Hormonal Response to Heavy Resistance Exercise in Women

Description: The purpose of this study was to examine the hormonal response to acute ethanol ingestion following a bout of heavy resistance exercise in women. Eight resistance trained women completed two identical acute heavy resistance exercise tasks (AHRET). From 10-20 minutes post-AHRET, participants consumed either a grain ethanol or a placebo beverage. Blood was collected before (PRE) and immediately after the AHRET (IP) and then every 20 minutes for five hours. Blood collected after beverage ingestion… more
Date: December 2015
Creator: Budnar, Ronald Gene, Jr.
Item Type: Refine your search to only Thesis or Dissertation
open access

A High-fat Meal Alters Post-prandial mRNA Expression of SIRT1, SIRT4, and SIRT6

Description: Sirtuins (SIRT) regulate the transcription of various genes involved in the development of diet-induced obesity and chronic disease; however, it is unknown how they change acutely following a high-fat meal. The purpose of this study was to determine the effect of a high-fat meal (65% kcals/d; 85% fat recommendation), on SIRT1-7 mRNA expression in blood leukocytes at 1, 3, and 5-h post-prandial. Men and women (N=24) reported to the lab following an overnight fast (>12H). Total RNA was isolated a… more
Date: December 2015
Creator: Best Sampson, Jill Nicole
Item Type: Refine your search to only Thesis or Dissertation
open access

Phenotypic Morphological Plasticity Induced by Environmental Salt Stress in the Brine Shrimp, Artemia franciscana

Description: Phenotypic plasticity is the ability of an organism to express different phenotypes in response to biotic or abiotic environmental cues. The ability of an organism to make changes during development to adjust to changes in its environment is a key to survival. Sexually reproducing organisms that have short life cycles and that are easy to raise in the laboratory are more conducive for developmental phenotypic plasticity. Considerable research has already been carried out on the brine shrimp, Ar… more
Date: December 2015
Creator: Jones, Shaun Gray
Item Type: Refine your search to only Thesis or Dissertation
open access

The Role of Cysteinyl Leukotriene Receptor 2 in Thrombocyte Aggregation

Description: Cysteinyl leukotriene receptor 2, a G-protein coupled receptor known to be expressed and functional on human platelets. However, it seems that upon ligand activation the cysteinyl leukotriene receptor 2 activates a variety of signaling pathways in multiple cell types among different species. Previously, a former laboratory member Vrinda Kulkarni found cysteinyl leukotriene receptor 2 to be expressed on the surface of adult zebrafish thrombocytes. In this work I studied the characteristics of ag… more
Date: December 2015
Creator: Reyna, Julianna
Item Type: Refine your search to only Thesis or Dissertation
open access

Cytotoxicity and Functional Toxicity of Mefloquine and the Search for Protective Compounds

Description: Mefloquine hydrochloride is an antimalarial agent that has been used for the past 40 years. Numerous reports of neurological side effects have recently led the FDA to issue a strong warning regarding long-term neurological effects. This warning lead to the U.S. Army’s Special Forces and other components to discontinue its use in July of 2013. Despite reported adverse side effects, mefloquine remains in circulation and is recommended to travelers going to specific Asian countries. Mefloquine … more
Date: May 2015
Creator: Holmes, Katelyn
Item Type: Refine your search to only Thesis or Dissertation
open access

Neurotoxicity of the Industrial Solvent 4-Methylcyclohexanemethanol: Involvement of the GABA Receptor

Description: A recent chemical spill of 4-Methylcyclohexanemethanol (4-MCHM) in West Virginia left 300,000 people without water. Officials claimed that this compound is not lethally toxic, but potentially harmful if swallowed or inhaled, and can cause eye and skin irritation. Sittig's Handbook of Toxic and Hazardous Chemical Carcinogens reports high exposures from skin contact or inhalation may cause damage to the heart, liver, kidneys, and lungs, and may result in death. However, no quantitative data seem… more
Date: May 2015
Creator: Gibson, Jason (Jason Robert)
Item Type: Refine your search to only Thesis or Dissertation
open access

Acute Effects of the Antibiotic Streptomycin on Neural Network Activity and Pharmacological Responses

Description: The purpose of this study is to find out that if antibiotic streptomycin decreases neuronal network activity or affects the pharmacological responses. The experiments in this study were conducted via MEA (multi-electrode array) technology which records neuronal activity from devices that have multiple small electrodes, serve as neural interfaces connecting neurons to electronic circuitry. The result of this study shows that streptomycin lowered the spike production of neuronal network, and also… more
Date: December 2014
Creator: Zeng, Wei Rong
Item Type: Refine your search to only Thesis or Dissertation
open access

Effects of Sertraline Exposure on Fathead Minnow (Pimephales promelas) Steroidogenesis

Description: Sertraline is a selective serotonin reuptake inhibitor (SSRI) that is widely used for the treatment of depression and anxiety. Due to the abundant therapeutic use of sertraline, low levels have been detected in municipal wastewater effluents suggesting that aquatic organisms may be exposed. The purpose of this study was to evaluate the steroidogenic effects of sertraline on larval (FHM) and adult female fathead minnows (FFHM), Pimephales promelas. Larval FHM were exposed to 0.1, 1, and 10 µg/L … more
Date: December 2014
Creator: Carty, Dennis R.
Item Type: Refine your search to only Thesis or Dissertation
open access

In Vitro Investigations of Antibiotic Influences on Nerve Cell Network Responses to Pharmacological Agents

Description: Neuronal networks, derived from mouse embryonic frontal cortex (FC) tissue grown on microelectrode arrays, were used to investigate effects of gentamicin pretreatment on pharmacological response to the L-type calcium channel blocker, verapamil. Gentamicin is a broad spectrum antibiotic used to control bacterial contamination in cell culture. The addition of gentamicin directly to medium affects the pharmacological and morphological properties of the cells in culture. A reproducible dose respons… more
Date: December 2014
Creator: Sawant, Meera
Item Type: Refine your search to only Thesis or Dissertation
open access

Measuring Biomarkers From Dried Blood Spots Utilizing Bead-based Multiplex Technology

Description: Dried blood spots is an alternative method to collect blood samples from research subjects. However, little is known about how hemoglobin and hematocrit affect bead-based multiplex assay performance. The purpose of this study was to determine how bead-based multiplex assays perform when analyzing dried blood spot samples. A series of four experiments outline the study each with a specific purpose. A total of 167 subject samples were collected and 92 different biomarkers were measured. Median fl… more
Date: December 2014
Creator: Prado, Eric A.
Item Type: Refine your search to only Thesis or Dissertation
open access

Monitoring Monocyte Oxldl Phagocytosis As a Cardiovascular Disease Risk Factor Following a High-fat Meal

Description: Macrophage-derived foam cells play a predominant role in the deposition of arterial plaques during the early stages of atherosclerosis. The deposition of arterial plaques is known to be effected by several factors, including a person’s dietary habits. The consumption of a high-fat (>60% of calories from fat) meal is known to elevate serum LDL and triglycerides, which have been previously implicated in the formation pf foam cells. One limitation of current research models is that it is not possi… more
Date: December 2014
Creator: Henning, Andrea L.
Item Type: Refine your search to only Thesis or Dissertation
open access

Optimization of Novel Culturing and Testing Procedures for Acute Effects on Acartia Tonsa and Tisbe Biminiensis

Description: Copepods comprise an ecologically important role in freshwater and marine ecosystems, which is why they are often considered an important ecotoxicological model organism. The International Organization for Standardization’s (ISO) 14669 protocol is the only guideline for the determination of acute toxicity in three European marine copepod species: Acartia tonsa. The goal of this project was to assess the feasibility of establishing and maintaining cultures of Acartia tonsa, as well as to refine … more
Date: December 2014
Creator: Ussery, Erin J.
Item Type: Refine your search to only Thesis or Dissertation
open access

Women Have Higher Skin Temperature on the Back during Treadmill Exercise in a Hot, Humid Environment

Description: A common measurement of body temperature during exercise in a hot, humid environment is mean skin temperature collected from 3-12 sites on the body. However, such an approach fails to demonstrate localized differences in skin temperature that are likely to exist as a function of gender. The purpose of this study was to examine potential differences in skin temperature between men and women at 17 different locations on the body. Young women (21 ± 1 y; n = 11) and men (23 ± 3; n = 10) were recrui… more
Date: August 2014
Creator: Venable, Adam Steven
Item Type: Refine your search to only Thesis or Dissertation
open access

The Effect of Menthol on Nicotine Metabolism: a Cross Species Evaluation

Description: The effect of menthol on nicotine metabolism was examined in liver S9 fractions of four different species and in the in vivo mouse model. The purpose of this study was to investigate three parameters: (1) biotransformation of nicotine to cotinine in various species (human, mouse, rat and trout) using in vitro methods; (2) to determine if the addition of menthol with nicotine altered biotransformation of nicotine to cotinine; (3) and to assess similar parameters in an in vivo mouse model. The… more
Date: December 2013
Creator: Pace, Wendy Lee
Item Type: Refine your search to only Thesis or Dissertation
open access

Effects of Airway Pressure, Hypercapnia, and Hypoxia on Pulmonary Vagal Afferents in the Alligator (Alligator Misssissippiensis)

Description: The American alligator (Alligator mississippiensis) is an aquatic diving reptile with a periodic breathing pattern. Previous work has identified pulmonary stretch receptors (PSR), both rapidly- and slowly-adapting, and intrapulmonary chemoreceptors (IPCs) that modulate breathing patterns in alligators. The purpose of the present study was to identify the effects of prolonged lung inflation and deflation (simulated dives) on PSR and/or IPC firing characteristics in the alligator. The effects of … more
Date: December 2013
Creator: Marschand, Rachel E.
Item Type: Refine your search to only Thesis or Dissertation
open access

Immunohistochemistry of the Gills of the Channel Catfish Ictalurus Punctatus: Cells and Neurochemicals That May Be Involved in the Control of Cardioventilatory Reflexes

Description: In teleost fishes the neurochemicals involved in sensing and responding to hypoxia are unresolved. Serotonergic branchial neuroepithelial cells (NECs) are putative O2 chemoreceptors believed to be homologous to the neural crest (NC) derived APUD (amine-precursor uptake and decarboxylation) pulmonary NECs and carotid body type-1 glomus cells. Branchial NECs contain serotonin (5-HT), thought to be central to the induction of the hypoxic cardioventilatory reflexes. However, application of 5-HT … more
Date: December 2013
Creator: Oden, David S.
Item Type: Refine your search to only Thesis or Dissertation
open access

Phototoxic Effects of Titanium Dioxide Nanoparticles on Daphnia Magna

Description: Titanium dioxide nanoparticles (TiO2-NP) are one of the most abundantly utilized nanomaterials in the world. Studies have demonstrated the mechanism of acute toxicity in TiO2-NP to be the production of reactive oxygen species (ROS) leading to oxidative stress and mortality in exposed organisms. It has also been demonstrated that the anatase crystalline conformation is capable of catalyzing the cleavage of water molecules to further increase the concentration of ROS in the presence of ultraviole… more
Date: December 2013
Creator: Mansfield, Charles M.
Item Type: Refine your search to only Thesis or Dissertation
open access

Shortened in Vivo Bioconcentration Factor Testing in Cyprinus Carpio

Description: Bioconcentration factor testing serves as the most valuable surrogate for the assessment of bioaccumulation. The assessment of potentially harmful chemicals is crucial to not only the health of aquatic environments, but to humans as well. Chemicals that possess the ability to persist in the environment or that have the potential to bioaccumulate, pose a greater risk to organisms that are exposed to these chemicals. The Organization for Economic Cooperation and Development Guideline 305 outlines… more
Date: December 2013
Creator: Cantu, Mark
Item Type: Refine your search to only Thesis or Dissertation
open access

Developing a Collection Digitization Workflow for the Elm Fork Natural Heritage Museum

Description: Natural history collections house immense amounts of data, but the majority of data is only accessible by locating the collection label, which is usually attached to the physical specimen. This method of data retrieval is time consuming and can be very damaging to fragile specimens. Digitizing the collections is the one way to reduce the time and potential damage related to finding the collection objects. The Elm Fork Natural Heritage Museum is a natural history museum located at the University… more
Date: August 2013
Creator: Evans, Colleen R.
Item Type: Refine your search to only Thesis or Dissertation
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