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Biology and Energetics of Tropisternus Lateralis Nimbatus (SAY) (Coleoptera: Hydrophilidae) in a Playa on the Southern High Plains of Texas and Aquatic Coleoptera Diversity from Seven Playas on the Southern High Plains of Texas (open access)

Biology and Energetics of Tropisternus Lateralis Nimbatus (SAY) (Coleoptera: Hydrophilidae) in a Playa on the Southern High Plains of Texas and Aquatic Coleoptera Diversity from Seven Playas on the Southern High Plains of Texas

A study of the biology of Tropisternus lateralis, a hydrophilid beetle, was conducted during the flood period of a single playa on the Southern High Plains of Texas from early June 1995 through early September 1995. Mechanism of colonization, tolerance/avoidance to drought, larval density, and secondary production were analyzed. T. lateralis colonized playas from surrounding aquatic habitats and avoided drought through aerial dispersion. Once in the playa, larval density increased over time. Secondary production was 1.31 g/m2/.25 yr. In addition, aquatic Coleoptera diversity was studied in seven playas on the Southern High Plains of Texas. A total of twenty three species were identified from the study region. Nine species not reported in playa literature were identified.
Date: December 1997
Creator: Cook, Robert E. (Robert Edward), 1969-
System: The UNT Digital Library
Comparison of Risk Assessment-Predicted Ecologically Safe Concentrations of Azinphos-Methyl and Fenvalerate to Observed Effects on Estuarine Organisms in a South Carolina Tidal Stream Receiving Agricultural Runoff (open access)

Comparison of Risk Assessment-Predicted Ecologically Safe Concentrations of Azinphos-Methyl and Fenvalerate to Observed Effects on Estuarine Organisms in a South Carolina Tidal Stream Receiving Agricultural Runoff

A prospective ecological risk assessment method was developed evaluating the cumulative probabilistic impact of chemical stressors to aquatic organisms. This method was developed in response to the need to evaluate the magnitude, duration and episodic nature of chemical stressors on aquatic communities under environmental exposure scenarios. The method generates a probabilistic expression of the percent of an ecosystem's species at risk from a designated chemical exposure scenario.
Date: August 1997
Creator: Morton, Michael Gerard, 1957-
System: The UNT Digital Library
Descriptions, Life History and Case-Building Behavior of Culoptila cantha (Trichoptera: Glossosomatidae) in the Brazos River, Texas (open access)

Descriptions, Life History and Case-Building Behavior of Culoptila cantha (Trichoptera: Glossosomatidae) in the Brazos River, Texas

Larval, pupal and adult samples of Culoptila cantha, from a large riffle of the Brazos River in north-central Texas from January, 1995 to March, 1997, indicated a predominately trivoltine cycle during both years; the over-wintering generation spanned 6-7 months and warm-season generations spanned 2-3 months. Eggs, larvae of all instars, larval cases, case reconstruction progression and behavior, pupae, and adults are described.
Date: August 1997
Creator: Houghton, David Charles
System: The UNT Digital Library
Distribution of a Novel Gram Negative, Capsule-Forming Bacterium (open access)

Distribution of a Novel Gram Negative, Capsule-Forming Bacterium

A novel Gram negative, capsule-forming bacterium was previously isolated in Dr. G. Roland Vela's laboratory. The distribution of this bacterium in soils from various locations was investigated. Soil samples from 188 locations around the world were examined. Isolates of the bacterium were obtained from 50 of these soils, with 48 of the isolates found in soils from the southwestern United States and northern Mexico. This suggests that this region is the natural habitat of the bacterium. The other two isolates were obtained from Madrid, Spain and Taipei, Taiwan. None were found in soils from South America or Australia. A lack of variation in morphology and physiological properties in the isolates suggests that a homogeneous population exists, even from widespread geographical locations.
Date: December 1997
Creator: Hughes, Roxana Bejarano
System: The UNT Digital Library
DNA Typing of HLA-B by PCR with Primer Mixes Utilizing Sequence-Specific Primers (open access)

DNA Typing of HLA-B by PCR with Primer Mixes Utilizing Sequence-Specific Primers

The aim of this study was to design a resolution typing system for the HLA-B gene. This technique involves a one-step PCR reaction utilizing genomic DNA and sequence-specific primers to determine the specificity of each allele and to produce a larger primer data base ideal for serological analysis. The application of this technique to serological analysis can improve serology detection which is currently hindered by antibody cross-reactivity and the unavailability of useful typing reagents.
Date: August 1997
Creator: Chiu, Angela Chen-Yen
System: The UNT Digital Library
Evaluation of the Use of the Bivalves Ischadium recurvum Rafinesque, 1820 and Corbicula fluminea Muller, 1774 as Biological Indicators of Relative Water Quality in Terms of Growth and Upper Temperature Tolerance (open access)

Evaluation of the Use of the Bivalves Ischadium recurvum Rafinesque, 1820 and Corbicula fluminea Muller, 1774 as Biological Indicators of Relative Water Quality in Terms of Growth and Upper Temperature Tolerance

Growth of mussels under laboratory conditions was examined under various food regimes in different water types and temperatures. Growth was less than would be useful as an indicator and comparisons with field exposures were of minimal value. The effects of organophosphates on bivalves were examined via toxicity tests, tissue concentration, and by controlling exposure through the use of physical constraints. Upper temperature tolerance of both bivalve species was examined with respect to different acclimation temperatures and organophosphate exposures. Deviations from control exposures occurred at some temperatures. Copper effectively lowered the mean heat coma temperatures of C. fluminea at some concentrations, however, chlorine exposures did not alter heat coma temperature.
Date: December 1997
Creator: Hemming, Jon Michael
System: The UNT Digital Library
Life History of Mayatrichia ponta Ross (Trichoptera: Hydroptilidae) in Honey Creek, Turner Falls Park, Oklahoma (open access)

Life History of Mayatrichia ponta Ross (Trichoptera: Hydroptilidae) in Honey Creek, Turner Falls Park, Oklahoma

The life history and ontogenetic microhabitat change of Mayatrichia ponta Ross were investigated in Honey Creek, Turner Falls Park, Murray Co., Oklahoma, U.S.A. from August 1994 to August 1995. The shape of larval cases changed from a small cone to a cylinder. M. ponta had an asynchronous multivoltine life history with considerable cohort and generation overlap; five generations were estimated. The development rate was reduced in winter. The winter generations of M. ponta had wider head capsule widths (136-165 μm) than summer generations (121-145 μm). The sex ratio of adults was 1.43 ♂ : 1 ♀. Fecundity ranged from 46 to 150 eggs/female. Fifth instar larvae and pupae aggregated on the bottom side of substrates. Early instars were distributed evenly on all sides of substrates. General patterns of ontogenetic microhabitat shift in aquatic insects are categorized as flow mediated, flow independent, and population interactions and other resources mediated.
Date: December 1997
Creator: Wang, Yi-Kuang
System: The UNT Digital Library
Nicotinic Acetylcholine Receptor α3 mRNA in Rat Visual System After Monocular Deprivation (open access)

Nicotinic Acetylcholine Receptor α3 mRNA in Rat Visual System After Monocular Deprivation

In situ hybridization was used to examine effects of monocular enucleation on nicotinic acetylcholine receptor subunit cc3 mRNA in the rat dLGNand visual cortex. After 28 days postoperative, there were no significant differences in α3 mRNA density between the contralateral (deprived) and ipsilateral (non-deprived) sides. The lack of obvious effects of visual deprivation on α3 mRNA density suggests that other factors, possibly intrinsic to dLGNand visual cortex, govern the postnatal expression of α3 mRNA.
Date: August 1997
Creator: Taylor, James H. (James Harvey), 1970-
System: The UNT Digital Library
Phagocytosis by Earthworm Coelomocytes : A Biomarker for Immunotoxicity of Hazardous Waste Site Soils (open access)

Phagocytosis by Earthworm Coelomocytes : A Biomarker for Immunotoxicity of Hazardous Waste Site Soils

Several biomarkers (cell viability and phagocytosis) based on earthworm (Lumbricus terrestris) immune cells (coelomocytes), together with whole-worm mortality (LC/LD50's), were used to assess a bioremediation attempt to reduce pentachlorophenol (PCP) toxicity in a former wood processing hazardous waste site (HWS).
Date: December 1997
Creator: Giggleman, Marina A.
System: The UNT Digital Library
The Role of Gabergic Inhibition in Modulating Receptive Field Size of Cuneate Neurons (open access)

The Role of Gabergic Inhibition in Modulating Receptive Field Size of Cuneate Neurons

A blockade of GABAergic inhibition increases the receptive field(RF) size of most somatosensory cortex (SI) and some ventrobasal thalamus (VB) neurons. The results suggest RF size of cuneate neurons may be modulated through GABAa and GABAb receptors, independent of firing frequency.
Date: August 1997
Creator: Tennison, Cullen F.
System: The UNT Digital Library
Subcloning and Nucleotide Sequence of the xylO/PUWCMA Region from the Pseudomonas putida TOL Plasmid pDK1 (open access)

Subcloning and Nucleotide Sequence of the xylO/PUWCMA Region from the Pseudomonas putida TOL Plasmid pDK1

The TOL plasmids of Pseudomonas putida encode enzymes required for the oxidation of toluene and other related aromatic compounds. These genes are organized into two operons, the xylUWCMABN operon (upper), and the xylXYZLTEGFJQKIH operon (lower). Here we report the nucleotide sequence of a 7107 bp segment of the TOL pDK1 plasmid encoding the region just upstream of the "upper" operon through the genes encoding xylUWCMA. Sequence analysis, comparison of base-usage patterns, codon-usage patterns, and intergenic distances between genes help support the idea that the "upper" and "lower" operons have evolved independently in different genetic backgrounds and have only more recently been brought together in TOL and related catabolic plasmids.
Date: December 1997
Creator: Guigneaux, Michelle M. (Michelle Marie)
System: The UNT Digital Library