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Green Improvements: A Consumer's Guide to Environmentally and Economically Responsible Home Repairs and Improvements for the North Central Texas Region

Description: The Consumer's Guide is designed to help consumers by providing guidelines for the purchase of specific energy-efficient household appliances- water heaters, air conditioning and heating systems, windows, dishwashers, refrigerators, clothes washers, and dryers. This serves two major purposes: to decrease the environmental impact of those products and to save consumers money over the lifetime of the products. The seven major appliances covered in this work are things that consumers tend to purch… more
Date: August 2004
Creator: Dickason, Deborah
Item Type: Refine your search to only Thesis or Dissertation
open access

Histological age estimation of the midshaft clavicle using a new digital technique.

Description: Histological methods to estimate skeletal age at death, in forensic cases, are an alternative to the more traditional gross morphological methods. Most histological methods utilize counts of bone type within a given field for their estimation. The method presented in this paper uses the percentage area occupied by unremodeled bone to estimate age. The percentage area occupied by unremodeled bone is used in a linear regression model to predict skeletal age at death. Additionally, this method use… more
Date: August 2004
Creator: Ingraham, Mark R.
Item Type: Refine your search to only Thesis or Dissertation
open access

Hematocrit, hematocrit Regulation and its effect on oxygen consumption in the late stage chicken embryo (Gallus domesticus).

Description: Hematocrit and hematocrit regulation have the potential to affect developing embryos. To examine the ability of chicken embryos at day 15 to regulate hematocrit, they were subjected to either repeated saline injections (5% of total blood volume) or repeated blood removal (5% of total blood volume). Embryos showed an ability to maintain hematocrit (~20%) despite blood volume increases up to 115% of initial blood volume. Embryos were not able to maintain hematocrit in the face of dramatic blood v… more
Date: August 2004
Creator: Khorrami, Sheva
Item Type: Refine your search to only Thesis or Dissertation
open access

Use of luminescence energy transfer probes to detect genetic variants.

Description: The purpose of this research was to study the hybridization of molecular beacons under different conditions and designs. Data collected suggest that the inconsistency found in the emission intensity of several of these probes may be caused by 3 important factors: length of the probe, nucleotide sequence and, the formation of an alternative complex structure such as a dimer. Of all three factors, dimer formation is the most troublesome, since it reduces the emission of the reporter molecules. A … more
Date: August 2004
Creator: Vaccaro, Carlos
Item Type: Refine your search to only Thesis or Dissertation
open access

Concentrations of Triclosan in the City of Denton Wastewater Treatment Plant, Pecan Creek, and the Influent and Effluent of an Experimental Constructed Wetland

Description: The Pecan Creek Waste Reclamation Plant in Denton, Texas, an activated sludge WWTP, was sampled monthly for ten months to determine seasonal and site variation in concentrations of triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol), an antibacterial additive. SNK separation after the highly significant ANOVA on ranked data were: summer = fall > winter = spring and influent > downstream = effluent = wetland inflow > wetland outflow (a=0.05). After the plant converted to ultraviolet disinfection… more
Date: August 2004
Creator: Waltman, Elise Lyn
Item Type: Refine your search to only Thesis or Dissertation
open access

Heart rate and oxygen consumption during the critical prenatal period in chicken embryos (Gallus gallus): Influence of light cues and the onset of pulmonary ventilation.

Description: To examine if a rhythm can be entrained in either heart rate or oxygen consumption in late stage embryos (days 17-19.5) with light as a zeitgeber, chicken embryos were incubated in complete darkness (D:D) and 12:12 light:dark cycle (L:D). Light had no impact on oxygen consumption (390 µL O2∙min-1∙egg-1) but increased heart rate for non-internally pipped embryos (260 to 270 beats∙min-1 during light cycle). Oxygen consumption increased independent of pipping while heart rate increased (255 to 2… more
Date: December 2004
Creator: Brown, Jessie W.
Item Type: Refine your search to only Thesis or Dissertation
open access

Isolation of a Pseudomonas aeruginosa Aspartate Transcarbamoylase Mutant and the Investigation of Its Growth Characteristics, Pyrimidine Biosynthetic Enzyme Activities, and Virulence Factor Production

Description: The pyrimidine biosynthetic pathway is an essential pathway for most organisms. Previous research on the pyrimidine pathway in Pseudomonas aeruginosa (PAO1) has shown that a block in the third step of the pathway resulted in both a requirement for exogenous pyrimidines and decreased ability to produce virulence factors. In this work an organism with a mutation in the second step of the pathway, aspartate transcarbamoylase (ATCase), was created. Assays for pyrimidine intermediates, and virule… more
Date: December 2004
Creator: Hammerstein, Heidi Carol
Item Type: Refine your search to only Thesis or Dissertation
open access

Concentration-dependent Effects of D-Methylphenidate on Frontal Cortex and Spinal Cord Networks in vitro

Description: Spontaneously active frontal cortex and spinal cord networks grown on microelectrode arrays were used to study effects of D-methylphenidate. These central nervous system tissues have relatively low concentrations of dopaminergic and noradrenergic neurons compared to the richly populated loci, yet exhibit similar neurophysiological responses to methylphenidate. The spontaneous spike activity of both tissues was inhibited in a concentration-dependent manner by serial additions of 1-500 µM methylp… more
Date: December 2004
Creator: Miller, Benjamin R.
Item Type: Refine your search to only Thesis or Dissertation
open access

Determination of Habitat Preferences of Pronghorn (Antilocapra americana) on the Rolling Plains of Texas Using GIS and Remote Sensing

Description: The Rocker b Ranch on the southern Rolling Plains has one of the last sizeable populations of pronghorn (Antilocapra americana) in Texas. To investigate habitat utilization on the ranch, pronghorn were fitted with GPS/VHF collars and were released into pastures surrounded by a variety of fences to determine how fence types affected habitat selection. Habitat parameters chosen for analysis were vegetation, elevation, slope, aspect, and distances to water, roads, and oil wells. Results showed … more
Date: May 2005
Creator: Aiken, Robin A.
Item Type: Refine your search to only Thesis or Dissertation
open access

Functional and Categorical Analysis of Waveshapes Recorded on Microelectrode Arrays

Description: Dissociated neuronal cell cultures grown on substrate integrated microelectrode arrays (MEAs) generate spontaneous activity that can be recorded for up to several weeks. The signature wave shapes from extracellular recording of neuronal activity display a great variety of shapes with triphasic signals predominating. I characterized extracellular recordings from over 600 neuronal signals. I have preformed a categorical study by dividing wave shapes into two major classes: (type 1) signals in … more
Date: May 2005
Creator: Schwartz, Jacob C.
Item Type: Refine your search to only Thesis or Dissertation
open access

Assessing Outcomes of a Recycling Education and Service Program within an Elementary School

Description: During the spring 2004 a pilot school recycling program was implemented within Robert E. Lee Elementary. The primary goal of the program was to determine how recycling education in the school would affect curbside recycling rates within the surrounding community. The program was a cooperative effort between the University of North Texas, City of Denton Solid Waste Department and Keep Denton Beautiful. Throughout the first months of the study during the spring 2004, an increase in curbside rec… more
Date: August 2005
Creator: Cunningham-Scott, Carey Beth
Item Type: Refine your search to only Thesis or Dissertation
open access

Mutation of Polaris, an Intraflagellar Transport Protein, Shortens Neuronal Cilia

Description: Primary cilia are non-motile organelles having 9+0 microtubules that project from the basal body of the cell. While the main purpose of motile cilia in mammalian cells is to move fluid or mucus over the cell surface, the purpose of primary cilia has remained elusive for the most part. Primary cilia are shortened in the kidney tubules of Tg737orpk mice, which have polycystic kidney disease due to ciliary defects. The product of the Tg737 gene is polaris, which is directly involved in a microtub… more
Date: August 2005
Creator: Mahato, Deependra
Item Type: Refine your search to only Thesis or Dissertation
open access

The Life History and Contributions to the Ecology of Camelobaetidius variabilis Wiersema 1998 (Ephemeroptera: Baetidae) in Honey Creek, Oklahoma

Description: A study of the life history and ecology of Camelobaetidius variabilis was conducted in Honey Creek, OK from February 2003-April 2004. Nymph development was assessed using changes in external morphology. Laboratory reared nymphs were used to calculate number of degree days to complete development (772 degree days at 20.8° C ±.38° C), which was used to determine voltinism. Field collected nymph microhabitat distribution was used in assessing microhabitat distribution. Nymphal thermoregulation … more
Date: December 2005
Creator: Perry, Heather A.
Item Type: Refine your search to only Thesis or Dissertation
open access

Rainfall-runoff changes due to urbanization: a comparison of different spatial resolutions for lumped surface water hydrology models using HEC-HMS.

Description: Hydrologic models were used to examine the effects of land cover change on the flow regime of a watershed located in North-Central Texas. Additionally, the effect of spatial resolution was examined by conducting the simulations using sub-watersheds of different sizes to account for the watershed. Using the Army Corps of Engineers, Hydrologic Engineering Center Hydrologic Modeling System (HEC-HMS), two different modeling methods were evaluated at the different sub-watershed resolutions for four … more
Date: December 2005
Creator: Redfearn, Howard Daniel
Item Type: Refine your search to only Thesis or Dissertation
open access

Analysis of the One-Horned Rhinoceros (Rhinoceros Unicornis) Habitat in the Royal Chitwan National Park, Nepal.

Description: This study analyzes the remaining suitable habitat of the one-horned rhinoceros, Rhinoceros unicornis, in Royal Chitwan National Park of Nepal. An April 2003 Landsat image was classified into eight land cover types: wetland, sand, water, mixed forest, sal forest, agriculture, settlement, and grassland. This image was converted into habitat suitability maps using cover, food, and water. The rhinoceros prefers grassland habitat with oxbow lakes and closed canopy during the monsoon season. Nomina… more
Date: December 2005
Creator: Thapa, Vivek
Item Type: Refine your search to only Thesis or Dissertation
open access

FLP-mediated conditional loss of an essential gene to facilitate complementation assays

Description: Commonly, when it is desirable to replace an essential gene with an allelic series of mutated genes, or genes with altered expression patterns, the complementing constructs are introduced into heterozygous plants, followed by the selection of homozygous null segregants. To overcome this laborious and time-consuming step, the newly developed two-component system utilizes a site-specific recombinase to excise a wild-type copy of the gene of interest from transformed tissues. In the first componen… more
Date: December 2007
Creator: Ganesan, Savita
Item Type: Refine your search to only Thesis or Dissertation
open access

The role of prostaglandins, nitric oxide and oxygen in the ductus arteriosi of the pre-term chicken embryo (Gallus domesticus).

Description: The chicken ductus arteriosi (DA) are two embryonic blood vessels that shunt blood away from the non-ventilated lungs and towards the body and chorioallantoic membrane. I show that prostaglandins have a diminished role in maintaining chicken DA patency and nitric oxide inhibits oxygen induced contraction of the day 19 proximal DA in a time dependent manner. The pathways governing oxygen induced contraction in the chicken DA are similar to those found in mammals and include contributions from RO… more
Date: December 2007
Creator: Greyner, Henry José
Item Type: Refine your search to only Thesis or Dissertation
open access

Home range analysis of rehabilitated and released great horned owls (Bubo virginianus) in Denton County, Texas, through radio telemetry.

Description: Raptor rehabilitation has become commonplace globally, yet studies on the survival and adaptation of great horned owls (Bubo virginianus) after release has been neglected to an appreciable extent. The primary objective of this study is to provide quantitative data on the success of rehabilitated and released great horned owls in the North Texas region. Owls (N=12) were rehabilitated and released onto the Ray Roberts Greenbelt Corridor in Denton County, Texas, and monitored using radio telemetry… more
Date: December 2007
Creator: Johnston, Jennifer Lynn
Item Type: Refine your search to only Thesis or Dissertation
open access

Physical Map between Marker 8O7 and 146O17 on the Medicago truncatula Linkage Group 1 that Contains the NIP Gene

Description: The Medicago truncatula NIP gene is located on M. truncatula Linkage Group 1. Informative recombinants showed crossovers that localize the NIP gene between markers 146O17 and 23C16D. Marker 164N9 co-segregates with the NIP gene, and the location of marker 164N9 is between markers 146O17 and 23C16D. Based upon data from the Medicago genome sequencing project, a subset of the model legume Medicago truncatula bacterial artificial chromosomes (BACs) were used to create a physical map on the DNA in … more
Date: December 2007
Creator: Lee, Yi-Ching
Item Type: Refine your search to only Thesis or Dissertation
open access

Optimization of Cell Culture Procedures for Growing Neural Networks on Microelectrode Arrays

Description: This thesis describes the development of an optimized method for culturing dissociated, monolayer neuronal networks from murine frontal cortex and midbrain. It is presented as a guidebook for use by cell culture specialists and laboratory personnel who require updated and complete procedures for use with microelectrode array (MEA) recording technology. Specific cell culture protocols, contamination prevention and control, as well common problems encountered within the cell culture facility, are… more
Date: December 2007
Creator: Santa Maria, Cara L.
Item Type: Refine your search to only Thesis or Dissertation
open access

Leaf elemental analysis and growth characteristics of mycorrhizal treated post oak seedlings via particle induced X-ray emission spectroscopy.

Description: Growth and element assimilation was investigated in post oak seedlings exposed to four different treatment combinations of fertilization and ectomycorrhizal inoculation. Element concentration in excised leaves was analyzed via particle induced X-ray emission spectrometry with a 1.8 MeV proton macrobeam. Mean growth was significantly different across the treatment groups as well as mean concentration of Mg, Al, S, K, Ca, Fe, Cu, and Zn. The data suggest that fertilization rather than mycorrhizal… more
Date: May 2006
Creator: Boling, Blake C.
Item Type: Refine your search to only Thesis or Dissertation
open access

Gene Flow among Populations of the Mayfly Epeorus pleuralis (Banks 1910) (Ephemeroptera: Heptageniidae) in Three Adjacent Appalachian Headwater Streams

Description: Dispersal of aquatic insects is difficult to measure with traditional direct trapping methodologies. However, genetic markers are an ideal surrogate to indirectly infer dispersal and gene flow. For this research, a portion of the cytochrome oxidase I gene was used to evaluate gene flow and dispersal of Epeorus pleuralis located in the northern Appalachian headwater streams of the Allegheny, Genesee, and Susquehanna watersheds. A total of 536 basepairs from 16 individual insects were used for… more
Date: May 2006
Creator: Dunlap, Rebecca
Item Type: Refine your search to only Thesis or Dissertation
open access

N-Acylethanolamine (NAE) Profiles Change During Arabidopsis Thaliana Seed Germination and Seedling Growth

Description: An understanding of the potential roles as lipid mediators of a family of bioactive metabolites called N-acylethanolamines (NAEs) depends on their accurate identification and quantification. The levels of 18C unsaturated NAEs (e.g. NAE18:2, NAE 18:3, etc.) in wild-type seeds (about 2000 ng/g fw) generally decreased by about 80% during germination and post-germinative growth. In addition, results suggest NAE-degradative fatty acid amide hydrolase (FAAH) expression does not play a major role in … more
Date: August 2006
Creator: Wiant, William C.
Item Type: Refine your search to only Thesis or Dissertation
open access

Coelomic Fluid Protein Profile in Earthworms Following Bacterial Challenge.

Description: Proteomic techniques were used to evaluate the protein profile of the earthworm, (Lumbricus terrestris), following a bacterial challenge. One control group received no injection; a second control group received injections of phosphate buffer solution (PBS). The experimental group received injections of PBS containing (Aeromonas hydrophila). After incubation for 12 hours at 20°C, coelomic fluid was collected from each group for analysis by 2-D electrophoresis. There were significant differences… more
Date: December 2006
Creator: Brooks, Geoffrey Lance
Item Type: Refine your search to only Thesis or Dissertation
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