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A Two Semester Life Science Syllabus for Use in Texas Public Schools with Seventh Grade Students

Description: The problem of using a state adopted textbook written to apply to a large body of students with varying interests and needs was overcome by using a detailed syllabus that arranged course content in a meaningful sequence that appealed to student interest. The outlined syllabus prepared a two semester life science curriculum to be used by the teacher to guide lesson planning. Both semesters were divided into three units each. Materials included in the syllabus were given to actual student groups … more
Date: May 1995
Creator: Edwards, Gail G. (Gail Graham)
Item Type: Refine your search to only Thesis or Dissertation
open access

Ultraviolet Radiation Tolerance in High Elevation Copepods from the Rocky Mountains of Colorado, USA

Description: Copepods in high elevation lakes and ponds in Colorado are exposed to significant levels of ultraviolet radiation (UV), necessitating development of UV avoidance behavior and photoprotective physiological adaptations. The copepods are brightly pigmented due to accumulation of astaxanthin, a carotenoid which has photoprotective and antioxidant properties. Astaxanthin interacts with a crustacyanin-like protein, shifting its absorbance from 473 nm (hydrophobic free form, appears red) to 632 nm (pr… more
Date: December 2011
Creator: Hudelson, Karista
Item Type: Refine your search to only Thesis or Dissertation
open access

Understanding Microbial Biodegradation of Environmental Contaminants

Description: The accumulation of industrial contaminants in the natural environments have rapidly become a serious threat for human and animal life. Fortunately, there are microorganisms capable of degrading or transforming environmental contaminants. The present dissertation work aimed to understand the genomic basis of microbial degradation and resistance. The focus was the genomic study of the following bacteria: a) Pseudomonas fluorescens NCIMB 11764, a unique bacterium with specific enzymes that allow… more
Date: May 2015
Creator: Vilo Muñoz, Claudia Andrea
Item Type: Refine your search to only Thesis or Dissertation
open access

Underwater Optical Properties of Lake Texoma (Oklahoma-Texas) Using Secchi Disk, Submarine Photometer, and High-Resolution Spectroscopy

Description: The underwater optical climate of Lake Texoma was measured at eleven fixed stations from August 1996 to August 1997. Secchi transparency and submarine photometry characterized seasonal and spatial values of secchi depth (SD), vertical attenuation coefficient (η''), and depth of euphotic zone (Zeu). Indices of Zeu:SD and η'' × SD were compared with universally applied values derived from inland and coastal waters. Turbidity explained 76% of the variation (p = 0.0001) of η'' among water quality p… more
Date: August 1998
Creator: Rolbiecki, David A. (David Alan)
Item Type: Refine your search to only Thesis or Dissertation
open access

Unique applications of cultured neuronal networks in pharmacology, toxicology, and basic neuroscience

Description: This dissertation research explored the capabilities of neuronal networks grown on substrate integrated microelectrode arrays in vitro with emphasis on utilizing such preparations in three specific application domains: pharmacology and drug development, biosensors and neurotoxicology, and the study of burst and synaptic mechanisms. Chapter 1 details the testing of seven novel AChE inhibitors, demonstrating that neuronal networks rapidly detect small molecular differences in closely related comp… more
Date: May 2001
Creator: Keefer, Edward W.
Item Type: Refine your search to only Thesis or Dissertation
open access

Upper and Lower Temperature Tolerances of Three Freshwater Game-Fish Species Exposed to Cycling Temperatures

Description: A total of 670 critical thermal maxima (CTMax) and minima (CTMin) were determined for three freshwater fishes acclimated to three constant temperatures and a diel regimen cycling between the lowest and highest acclimation temperatures. In all species temperature tolerance was directly related to acclimation temperature and slopes relating these variables indicate that acclimation temperature has a greater influence on tolerance of low rather than high temperatures. CTMax and CTMin values genera… more
Date: August 1995
Creator: Currie, Rebecca J. (Rebecca Jean)
Item Type: Refine your search to only Thesis or Dissertation
open access

Use of ATP as a Planktonic Biomass Indicator in Reservoir Limnology

Description: A series of laboratory experiments and a field investigation were conducted to closely define the application of the ATP assay and ATP as a planktonic biomass estimator for routine use in reservoir limnology. The laboratory experiments verified the published range of C:ATP ratios (i.e. 250:1) as a conversion factor for ATP to biomass in cultured selected genera of freshwater algae, except for the species of blue-green algae examined. The field investigation conducted at Moss Reservoir included… more
Date: August 1978
Creator: Perry, William B.
Item Type: Refine your search to only Thesis or Dissertation

Use of Geographic Information System and Remote Sensing Technologies to Describe Mosquito Population Dynamics in the Ray Roberts Greenbelt, Denton County, Texas

Description: A population survey was conducted from April through September 2002 on mosquito species occurring on the Ray Roberts Greenbelt, a riparian corridor used for public recreation on the Elm Fork of the Trinity River, in Denton County, Texas. ArcGIS software was used to set up a stratified random sampling design based on habitat parameters. Multivariate analyses of sampling data and climatic variables were used to describe spatial and temporal patterns of mosquito species. A total of 33 species were… more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: May 2003
Creator: Bolling, Bethany G.
Item Type: Refine your search to only Thesis or Dissertation
open access

Use of geographic information systems for assessing ground water pollution potential by pesticides in central Thailand

Description: This study employed geographic information systems (GIS) technology to evaluate the vulnerability of groundwater to pesticide pollution. The study area included three provinces (namely, Kanchana Buri, Ratcha Buri, and Suphan Buri) located in the western part of central Thailand. Factors used for this purpose were soil texture, percent slope, primary land use, well depth, and monthly variance of rainfall. These factors were reclassified to a common scale showing potential to cause groundwater co… more
Date: August 2002
Creator: Thapinta, Anat
Item Type: Refine your search to only Thesis or Dissertation
open access

Use of GIS and Remote Sensing Technologies to Study Habitat Requirements of Ocelots, Leopardus pardalis, in south Texas

Description: The goals of this study were to use Geographic Information Systems (GIS) and remote sensing technologies to gain a better understanding of habitat requirements of a population of ocelots in south Texas, and then apply this knowledge to form a predictive model to locate areas of suitable habitat in Willacy and Cameron counties, Texas. Satellite imagery from August 1991 and August 2000 were classified into four land cover types: closed canopy, open canopy, water, and urban/barren. These classifie… more
Date: August 2002
Creator: Jackson, Victoria L.
Item Type: Refine your search to only Thesis or Dissertation
open access

Use of In-Stream Water Quality Measurements and Geospatial Parameters to Predict Consumer Surfactant Toxic Units in the Upper Trinity River Watershed, Texas

Description: Surfactants are used in a wide assortment of "down-the-drain" consumer products, yet they are often discharged in wastewater treatment plant effluent into receiving water, potentially causing environmental harm. The objective of this project was to predict surfactant toxic units and in-stream nutrients in the upper Trinity River watershed. Surface and pore water samples were collected in late summer 2005. General chemistries and surfactant toxic units were calculated. GIS models of anthropo… more
Date: May 2008
Creator: Johnson, David Richard
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

Use of Satellite Imagery and GIS to Model Brood-Rearing Habitat for Rio Grande Wild Turkey Populations Occurring in the Western Cross Timbers Region of Texas

Description: Remote sensing and GIS have become standard tools for evaluating spatial components of wildlife habitats. These techniques were implemented to evaluate Rio Grande wild turkey (Meleagris gallopavo) poult-rearing habitat in the Western Cross Timbers region of Texas. Texas Parks and Wildlife (TPWD) random roving turkey counts for 1987-1989 and 1998-2000 were selected, indicating locations where hens with poults were observed. Satellite imagery from 1988 and 1999 was classified and then processed w… more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: August 2002
Creator: Miller, Christopher J.
Item Type: Refine your search to only Thesis or Dissertation
open access

Use of tRNA Gene Probes to Identify Polymorphic Loci in the Bovine Genome

Description: A 30-mer oligonucleotide probe encoding the "A box" and anticodon loop regions of a human glycine tRNA gene was used to isolate a 581bp DNA fragment from a bovine genomic DNA library. Although the cross-hybridizing segment of DNA was found not to encode any tRNA gene or pseudogene, a region with homology to the "C-element" of the "BOV-tA" type Alulike artiodactyl retroposons was identified. This cross-hybridization was determined to be the result of conserved RNA polymerase III promoter element… more
Date: August 1998
Creator: Shariat, Parvaneh
Item Type: Refine your search to only Thesis or Dissertation

Utilization of Corridor Habitat by White-tailed Deer (Odocoileus virginianus) in Denton County, Texas

Description: White-tailed deer (Odocoileus virginianus) (N=15) movements were determined with use of radio telemetry techniques to determine the utilization of corridor habitat on the Lake Ray Roberts Greenbelt Corridor (RRGC) in north central Texas. Home ranges were calculated using three estimation types. Male white-tailed deer tend to have home ranges twice that of female home ranges. Seasonal home ranges were largest during spring (Feb. - April) and fall (Aug. - Oct.) seasons. Males had greater seasonal… more
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Date: May 2004
Creator: Bruce, Troy Kenneth
Item Type: Refine your search to only Thesis or Dissertation
open access

Validation of a Coupled Herbicide Fate and Target Plant Species Effects Model

Description: A series of experiments provided data to parameterize and validate a coupled herbicide fate and target plant species effects model. This simulation model is currently designed to predict responses of water hyacinth populations to treatments of the dimethylamine formulation of 2,4- dichloro-phenoxy acetic acid (2,4-D -DMA). Experiments investigated 1) the response of water hyacinth to varying exposures of 2,4-D (DMA); 2) the role of water hyacinth density and herbicide interception in treatment … more
Date: December 1989
Creator: Clifford, Philip A. (Philip Alan)
Item Type: Refine your search to only Thesis or Dissertation
open access

The Vertical Stratification of the Macrobenthos in the Brazos River, Texas

Description: Quantification of stream macrobenthos populations has remained a perplexing problem in rivbrine ecology, despite numerous attempts at improvement. This is in part due to well documented variations in chemical and physical parameters locally and geographically, and resultant adapted macrobenthos populations. Southwood (1968) and Hynes (1970a) have reviewed the various sampling techniques developed'for the census of lotic macrobenthos populations. Needham and Usinger (1956), Chutter (1969), and o… more
Date: December 1973
Creator: Poole, Walton Charles
Item Type: Refine your search to only Thesis or Dissertation
open access

Virulence Factor Production in PyrE Mutants of Pseudomonas Aeruginosa

Description: It has been shown previously in our lab that mutations in the pyrimidine pathway reduced the ability of Pseudomonas aeruginosa to produce virulence factors. Knockout mutations in pyrB, pyrC and pyrD genes of the pyrimidine pathway showed that virulence factor production was decreased. Pyoverdin, pyocyanin, hemolysin, iron chelation, motility, and adherence are all considered virulence factors. Here I further investigate the effects of mutations in the pyrimidine pathway by studying a pyrE mutan… more
Date: May 2010
Creator: Niazy, Abdurahman
Item Type: Refine your search to only Thesis or Dissertation
open access

Water Quality Aspects of an Intermittent Stream and Backwaters in an Urban North Texas Watershed

Description: Pecan Creek flows southeast through the City of Denton, Texas. Characterized as an urban watershed, the basin covers approximately 63.5 km2. Pecan Creek is an intermittent stream that receives nonpoint runoff from urban landuses, and the City of Denton's wastewater treatment plant, Pecan Creek Water Reclamation Plant, discharges effluent to the stream. Downstream from the City of Denton and the wastewater treatment plant, Pecan Creek flows about 6,000 m through agricultural, pasture, and for… more
Date: August 2002
Creator: Taylor, Ritchie Don
Item Type: Refine your search to only Thesis or Dissertation
open access

Water Quality Mapping on Lake Texoma USA

Description: The primary objective of this study was to develop and evaluate a system capable of rapid, continuous collection of water quality and locational data on Lake Texoma. Secondary objectives included developing monthly distribution maps for chlorophyll-a, turbidity, and specific conductivity in Lake Texoma and investigating the spatial and temporal relationships between these common water quality indicators. A modified YSI multiprobe was used to develop a system capable of surveying the lake within… more
Date: December 2002
Creator: Mabe, Jeffrey A.
Item Type: Refine your search to only Thesis or Dissertation
open access

Wind Energy-related Wildlife Impacts: Analysis and Potential Implications for Rare, Threatened and Endangered Species of Birds and Bats in Texas

Description: Texas currently maintains the highest installed nameplate capacity and does not require publicly available post-construction monitoring studies that examine the impacts of wind energy production on surrounding fauna. This thesis examines potential wind energy impacts on avian and bat species in Texas through a three-part objective. The first two objectives synthesize literature on variables attractive to species within wind development areas and estimate impacted ranges outside of Texas, based … more
Date: August 2010
Creator: Graham, Tara L.
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

X-irradiation Effects on the Action Potentials of Frog Sciatic Nerves Inhibited by Carbon Monoxide and Ouabain

Description: The response of frog sciatic nerve action potentials to x-irradiation and metabolic (carbon monoxide) or transport (ouabain) inhibition was determined in an attempt to further identify the nature of radiation insult to nervous tissue. Carbon monoxide, ouabain (2 X 10-5 M), and nitrogen anoxia were shown to produce a near linear decline in action potential amplitude. The carbon monoxide and nitrogen inhibitions of activity were reversible in air; the carbon monoxide inhibition was light reversib… more
Date: December 1971
Creator: Thompson, Wesley J.
Item Type: Refine your search to only Thesis or Dissertation
open access

Zebrafish Von Willebrand Factor

Description: In humans, von Willebrand factor (vWF) is a key component in hemostasis and acts as a 'cellular adhesive' by letting the circulating platelets bind to exposed subendothelium. It also acts as a carrier and stabilizer of factor VIII (FVIII). A dysfunction or reduction of vWF leads to von Willebrand disease (vWD), resulting in bleeding phenotype which affects 1% of the population. Currently there are a variety of animal models used for the study of vWF and vWD; however, they do not possess the … more
Date: August 2012
Creator: Carrillo, Maira M.
Item Type: Refine your search to only Thesis or Dissertation
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