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  Partner: UNT Libraries
 Department: Department of Biological Sciences
 Collection: UNT Theses and Dissertations
Applications of remote sensing and GIS to modeling fire for vegetative restoration in Northern Arizona

Applications of remote sensing and GIS to modeling fire for vegetative restoration in Northern Arizona

Date: August 2003
Creator: Hardison, Tanya
Description: An accurate fire model is a useful tool in predicting the behavior of a prescribed fire. Simulation of fire requires an extensive amount of data and can be accomplished best using GIS applications. This paper demonstrates integrative procedures of using of ArcGIS™, ERDAS Imagine™, GPS, and FARSITE© to predict prescribed fire behavior on the Kaibab-Paiute Reservation. ArcGIS was used to create a database incorporating all variables into a common spatial reference system and format for the FARSITE model. ArcGIS Spatial Analyst was then used to select optimal burn sites for simulation. Our predictions will be implemented in future interagency efforts towards vegetative restoration on the reservation.
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The aquatic insect communities of Holbrook Creek and Cochetopa Creek in Colorado.

The aquatic insect communities of Holbrook Creek and Cochetopa Creek in Colorado.

Date: December 2003
Creator: Wallace, Mark Allen
Description: The first objective for this problem in lieu of thesis project was to gather, identify to the lowest practical taxonomic level and organize all available aquatic insects collected from high altitude Colorado aquatic systems during the summers of 1994, 1996, 1998, and 2002 for the University of North Texas Environmental Science Field Course (BIOL 5650). The curated collection will be housed in the Elm Fork Natural History Museum, located at the University of North Texas. The second objective was to provide a summary and discussion of the occurrence and distribution of the aquatic insects collected from Mt. Blanca in 1994, 1996, and 1998 and to create a taxa list of aquatic insects collected from Cochetopa Creek during the summer of 2002.
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Aspartate transcarbamoylase of Aeromonas hydrophila

Aspartate transcarbamoylase of Aeromonas hydrophila

Date: December 2000
Creator: Higginbotham, Leah
Description: This study focused on the enzyme, aspartate transcarbamoylase (ATCase) from A. hydrophila, a Gram-negative bacterium found in fresh water. The molecular mass of the ATCase holoenzyme from A. hydrophila is 310 kDa. The enzyme is likely composed of 6 catalytic polypeptides of 34 kDa each and 6 regulatory polypeptides of 17 kDa each. The velocity-substrate curve for A. hydrophila ATCase is sigmoidal for both aspartate and carbamoylphosphate. The Km for aspartate was the highest to date for an enteric bacterium at 97.18 mM. The Km for carbamoylphosphate was 1.18 mM. When heated to 60 ºC, the specific activity of the enzyme dropped by more than 50 %. When heated to 100 ºC, the enzyme showed no activity. The enzyme's activity was inhibited by ATP, CTP or UTP.
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Assembly of Pseudomonas putida Aspartate Transcarbamoylase and Possible Roles of the PyrC' Polypeptide in the Folding of the Dodecameric Enzyme

Assembly of Pseudomonas putida Aspartate Transcarbamoylase and Possible Roles of the PyrC' Polypeptide in the Folding of the Dodecameric Enzyme

Date: May 1999
Creator: Hongsthong, Apiradee, 1970-
Description: Aspartate transcarbamoylase (ATCase) of Pseudomonas putida consists of two different polypeptides, PyrB and PyrC' (Schurr et al, 1995). The role of the PyrC' and the assembly of PyrB and PyrC' have been studied. The ATCase made in vitro of P.putida PyrB with P.putida PyrC', and of E.coli PyrB with P.putida PyrC ' were generated under two different conditions, denaturation and renaturation, and untreated. It was found that PyrC' plays a role in the enzymatic regulation by ATP, CTP and UTP. In addition to playing a role in substrate binding, the PyrB polypeptide is also involved in effector binding (Kumar et al., manuscript in preparation). The most energetically preferred form of the P.putida WT is a dodecamer with a molecular mass of 480 kDa. The ratio between the PyrB and the PyrC' is 1:1. In studies of nucleotide binding, it was discovered that the P.putida PyrB was phosphorylated by a protein kinase in the cell extract. In the presence of 20 mM EDTA, this phosphorylation was inhibited and the inhibition could be overcome by the addition of divalent cations such as Zn2+ and Mg2+. This result suggested that the phosphorylation reaction required divalent cations. In the CAD complex of eukaryotes, phosphorylations ...
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Assessing Outcomes of a Recycling Education and Service Program within an Elementary School

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

Date: August 2005
Creator: Cunningham-Scott, Carey Beth
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 recycling within the Robert E. Lee Elementary attendance zone was observed, with a dramatic decrease in participation over the summer and a rapid increase once again during the second full semester of the study. In a survey conducted with 3rd and 5th grade students at the pilot project school, most students expressed positive attitudes about recycling. Students whose survey responses indicated a high level of knowledge about what could be recycled were 37% more likely to claim to recycle regularly, than those students that scored low on the knowledge portion of the survey. Although the total amount of waste generation (recyclable and non-recyclable) at Robert E. Lee Elementary did not decrease during the study, the campus was able to divert recyclable material from ...
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Assessing the Effects of a Municipal Wastewater Treatment Plant Effluent on Zooplankton, Phytoplankton and Corbicula Flumina in a Constructed Wetland

Assessing the Effects of a Municipal Wastewater Treatment Plant Effluent on Zooplankton, Phytoplankton and Corbicula Flumina in a Constructed Wetland

Date: May 1995
Creator: Hymel, Stephanie Ramick
Description: Wetland wastewater treatment offers low-cost, energy efficient alternatives to conventional wastewater technologies. In this study, an artificial wetland was constructed at the City of Denton, Texas Pecan Creek Water Reclamation Plant to facilitate diazinon removal from treated effluent.
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Assessing the Spatial and Temporal Distribution of MTBE and BTEX Compounds in Lake Lewisville, Texas February 1999 - February 2000

Assessing the Spatial and Temporal Distribution of MTBE and BTEX Compounds in Lake Lewisville, Texas February 1999 - February 2000

Date: August 2000
Creator: Lee, Anne W.
Description: The spatial and temporal distribution of Methyl Tertiary-Butyl Ether (MTBE) and BTEX (Benzene, Toluene, Ethylbenzene, Xylenes) compounds were assessed in a multipurpose reservoir, Lake Lewisville, Texas between February 1999 and February 2000. Concentrations of MTBE ranged from 0.0 - 16.7 mg/L. Levels of MTBE in the lake were related to watercraft. BTEX concentrations were never detected above 2.0 mg/L during the sampling period. Finished drinking water from Denton and the Upper Trinity Regional Water District (UTRWD) Treatment Plants were also tested for MTBE and BTEX. MTBE and BTEX were not detected in UTRWD water samples. Denton's finished water samples never exceeded 2.2 mg/L for MTBE and BTEX was not detected except for one replicate of 1.1 mg/L toluene.
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An Assessment of Storm Water Toxicity from the Dallas/Fort Worth Metroplex and Denton, Texas

An Assessment of Storm Water Toxicity from the Dallas/Fort Worth Metroplex and Denton, Texas

Date: August 1995
Creator: Keating, Paul Redmond
Description: With the advent of national storm water regulations, municipalities with populations greater than 100,000 are required to obtain National Pollutant Discharge Elimination System Permits (NPDES) for storm water discharges. In addition to the sampling required for the permit process, the City of Fort Worth contracted with the University of North Texas' Institute of Applied Sciences to conduct acute toxicity testing using Pimephales prcmelas and Ceriodaphnia dubia on storm water samples received from the Dallas/Fort Worth Metroplex. A Toxicity Identification Evaluation (TIE) was performed on four samples that exhibited acute toxicity to C. dubia. High levels of metals as well as diazinon were some of the probable toxicants found.
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An Assessment of the Use of Seeding, Mowing, and Burning in the Restoration of an Oldfield to Tallgrass Prairie in Lewisville, Texas

An Assessment of the Use of Seeding, Mowing, and Burning in the Restoration of an Oldfield to Tallgrass Prairie in Lewisville, Texas

Date: August 1999
Creator: Windhager, Steven
Description: An examination of the effectiveness of seeding, burning, and mowing in the reestablishment of tallgrass prairie species on overgrazed and abandoned pastureland. The study site is a 20 acre tract on U.S. Corps of Engineers land below Lake Lewisville in Denton County, Texas. The site was partitioned into thirty-nine 40 by 40 meter plots with seeding (carried out in 1996) and management treatment (burning, mowing, and no maintenance carried out in 1998) randomly applied following a two level design. For each plot, nine stratified-random 0.1 m2 subplots were examined and shoot counts for each species recorded. The effects of the treatments on individual species and species richness were analyzed with a two-way ANOVA followed by a SNK multiple range test, both on ranked data. Community level analysis was conducted with both a MANOVA on ranked data and a Canonical Correspondence Analysis on raw data. Results indicate that seeding positively affected species richness, particularly when combined with either burning or mowing in the early spring. Mowing also significantly increased species richness in areas that were not seeded, while burning negatively affected species richness on unseeded plots. Treatments significantly affected community composition with treatments having the most clear effect on spring and ...
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Attenuation of Escherichia Coli Aspartate Transcarbamoylase Expressed in Pseudomonas Aeruginosa Mutant and Wild Type Strains

Attenuation of Escherichia Coli Aspartate Transcarbamoylase Expressed in Pseudomonas Aeruginosa Mutant and Wild Type Strains

Date: December 1994
Creator: Liu, Haiyan, 1966-
Description: No apparent repression of pyr gene expression in Pseudomonas aeruginosa is observed upon addition of exogenous pyrimidines to the growth medium. Upon introduction of the subcloned Escherichia coli pyrBI genes for aspartate transcarbamoylase (ATCase) into a P. aeruginosa pyrB mutant strain, repression was observed in response to exogenously fed pyrimidine compounds. The results proved that it is possible to bring about changes in pyrimidine nucleotide pool levels and changes in transcriptional regulation of gene expression as a result. Thus, the lack of regulatory control in P. aeruginosa pyr gene expression is not due to an inability to take up and incorporate pyrimidine compounds into metabolic pools, or to an inability of the RNA polymerase to respond to regulatory sequences in the DNA but is probably due to a lack of specific regulatory signals in the promoter of the genes themselves.
Contributing Partner: UNT Libraries