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Comparative Toxicity of Refuse-Derived Fuel Fly Ash on Two Species of Earthworms, Lumbricus terrestris and E. foetida, Using an Artificial Soil Exposure Protocol

Description: Research estimated toxicity of refuse-derived fuel fly ash (RDF-FA) on two earthworms species, Lumbricus terrestris and Eisenia foetida. Specific objectives were to: (1) Compare their 14-day LC50s under light and dark conditions; (2) separate toxicity due to osmotic, pH and physical factors from that of heavy metal contaminants; (3) compare relative differences of artificial soil and commercial soil as exposure media for evaluating toxicity to earthworms. The 14-d LC50s for L. terrestris in dark and light were 57.0 and 48.34 % RDF-FA, and 59.25 and 41.00 % RDF-FA for E. foetida using artificial soil. All of the toxicity resulted from heavy metals within the RDF-FA. Using L. terrestris, the LC50s for artificial soil and commercial soil were 52.30 and 64.34%.
Date: May 1991
Creator: Jahani, Aghamolla

Biodiversity of Dragonflies and Damselflies (Odonata) of the South-Central Nearctic and Adjacent Neotropical Biotic Provinces

Description: The south-central United States serves as an important biogeographical link and dispersal corridor between Nearctic and Neotropical elements of western hemisphere odonate faunas. Its species are reasonably well known because of substantial collections, but there has been no concerted effort to document the extent of biodiversity and possible geographic affinities of dragonflies and damselflies of this region. The recent discoveries of Argia leonorae Garrison, Gomphus gonzalezi Dunkle and Erpetogomphus heterodon Garrison from southern and western Texas and northern Mexico suggest that Odonata species remain to be discovered in this area, particularly from far south Texas and northern Mexico. I have documented a total of 12,515 records of Odonata found in 408 counties within the south-central U.S. A total of 73 species of damselflies and 160 species of dragonflies was revealed in the region. The 233 (197 in Texas) Odonata species are distributed among 10 families and 66 genera. Illustrated family, generic, and species-level keys are provided. Since the beginning of this work in the Fall of 1993, one species has been added each to the Louisiana and Oklahoma faunas, and 12 species have been added, previously unreported from Texas, including four new to the U.S. The area of highest Odonata biodiversity overall (161 spp.) is in the Austroriparian biotic province. The greatest degree of faunal similarity between the south-central U.S. and other intra-continental regions was observed for the eastern (64%) United States. Diversity is a function of area, and as expected, the numbers of breeding birds and Odonata, in each contiguous U.S. state are positively correlated (r=0.376, n=33, p=0.031). There is, however, no strong correlation between land area and species diversity within the region, but those natural biotic provinces (Austroriparian, Texan, Balconian) where aquatic systems and topographic heterogeneity are the greatest provide a broader spectrum of potential Odonata habitats and ...
Date: May 1999
Creator: Abbott, John C.

Comparative Biochemistry and Evolution of Aspartate Transcarbamoylase from Diverse Bacteria

Description: Aspartate transcarbamoylase (ATCase) catalyzes the first committed step in pyrimidine biosynthesis. Bacterial ATCases are divided into three classes, A, B and C. Class A ATCases are largest at 450-500, are. dodecamers and represented by Pseudomonas ATCase. The overlapping pyrBC' genes encode the Pseudomonases ATCase, which is active only as a 480 kDa dodecamer and requires an inactive pyrC'-encoded DHOase for ATCase activity. ATCase has been studied in two non-pathogenic members of Mycobacterium, M. smegmatis and M. phlei. Their ATCases are dodecamers of molecular weight 480 kDa, composed of six PyrB and six PyrC polypeptides. Unlike the Pseudomonas ATCase, the PyrC polypeptide in these mycobacteria encodes an active DHOase. Moreover, the ATCase: DHOase complex in M. smegmatis is active both as the native 480 kDa and as a 390 kDa complex. The latter lacks two PyrC polypeptides yet retains ATCase activity. The ATCase from M. phlei is similar, except that it is active as the native 480 kDa form but also as 450,410 and 380 kDa forms. These complexes lack one, two, and three PyrC polypeptides, respectively. By contrast,.ATCases from pathogenic mycobacteria are active only at 480 kDa. Mycobacterial ATCases contain active DHOases and accordingly. are placed in class A1 . The class A1 ATCases contain active DHOases while class A2 ATCases contain inactive DHOases. ATCase has also been purified from Burkholderia cepacia and from an E. coli strain in which the cloned pyrB of B. cepacia was expressed. The B. cepacia ATCase has a molecular mass of 550 kDa, with two different polypeptides, PyrB (52 kDa) and PyrC of (39 kDa). The enzyme is active both as the native enzyme at 550 kDa and as smaller molecular forms including 240 kDa and 165 kDa. The ATCase synthesized by the cloned pyrB gene has a molecular weight of 165 kDa composed ...
Date: May 1999
Creator: Hooshdaran, Massoumeh Ziba

Mutagenized HLA DNA Constructs: Tools for Validating Molecular HLA Typing Methodologies

Description: This study describes the development and validation of mutagenized cloned DNA constructs, which correspond to the polymorphic regions of the class II region of the HLA complex. The constructs were used to verify the allelic specificity of primers and probes in polymerase chain reaction (PCR)-based HLA typing assays such as Sequence Specific Primers (SSP) and Sequence Specific Oligonucleotide Probes (SSOP). The constructs consisted of the entire polymorphic region of exon 2 of class II HLA allele sequences that included primer annealing sites or probe hybridization sites. An HLA allele sequence was inserted into a plasmid, cloned, then mutagenized to match a specific HLA allele, and finally, the correct clone was verified by bidirectional sequencing of the insert. Thus, the construct created a cloned reference DNA sample for any specific allele, and can be used to validate the accuracy of various molecular methodologies.
Date: May 1999
Creator: Schulte, Kathleen Q.

Isolation and Characterization of a New Capsule-Forming Bacterium

Description: A unique, previously undescribed Gram-negative bacterium was isolated from several soils in Texas and extensively characterized in this study. The cells measured 1-2 by 4-6 μm. The distinguishing characteristic of the bacterium is the extraordinary capsular material which surrounds the cells. The new isolates are aerobic, mesophilic, non motile and have the ability to utilize a variety of organic compounds as the sole source of carbon and energy. The organism grows optimally at 30° C and the optimal pH lies between 7.0-8.0. The isolates produce catalase but oxidase is not produced. They do not produce indole or hydrogen sulfide. The organism can hydrolyze gelatin and Tween 80 but not starch, esculin and casein. The major cellular fatty acid is anteiso 15:0. The guanine and cytosine content is 58-62 mole%. The organism's taxonomic position was further established by specific gene probes, 16S rRNA homology, DNA homology and "ribotyping." These data showed that it was most closely related to members of the genus Paenibacillus, although somewhat divergent from other species classified in this genus. After careful evaluation of the results obtained during this study, it is proposed that this unique bacterium be named Paenibacillus velasolus sp. nov.
Date: May 1999
Creator: Thongmee, Acharawan

Biogeographic Relationships of Pocket Gophers (Geomys breviceps and Geomys bursarius) in the Southeastern Portion of Their Ranges

Description: This research utilized population genetic analyses (protein starch-gel electrophoresis and DNA sequencing of the cytochrome b mtDNA gene), host-parasite specificity (lice coevolution), remote sensing of satellite data, and geographic information systems (GIS) to characterize newly discovered populations of pocket gophers (genus: Geomys) in Arkansas. These populations are isolated and occur in seemingly unsuitable habitat in the Ozark Mountains of Arkansas. Analyses of electrophoretic and ectoparasite data suggested the populations in the Ozark Mountains represented isolates allied to Geomys bursarius, a species not known to occur in Arkansas. Comparison of mitochondrial DNA sequence data of the cytochrome b gene with that of other taxa and morphometric analyses confirmed that these populations are most closely allied to G. bursarius occurring to the north in Missouri. Moreover, these mtDNA sequence analyses indicated a degree of differentiation typical of that between other subspecies of pocket gophers. Therefore, these populations represent a distinct genetic entity in an intermediate stage of speciation and should be designated as a new subspecies, Geomys bursarius ozarkensis. Molecular clock analysis revealed a time of lineage divergence for this new subspecies as approximately 511,000 YBP. Due to the isolated nature and limited distribution of this subspecies, an evaluation of critical habitat needs was initiated. Remote sensing and GIS technologies were used to identify and describe suitable habitat Computerized classification of satellite imagery of suitable vegetation, integrated with ancillary digital information on soil associations, roads, and water systems, revealed that human activity had played a positive role in the establishment and dispersal of pocket gophers in this area. This research represents an initial combination of classical systematic tools with remote sensing and GIS to investigate biogeographic patterns and evolution. This project establishes a framework for using an interdisciplinary approach to studying organisms with limited distributions, determining evolutionary status, and providing recommendations for ...
Date: August 1998
Creator: Elrod, Douglas Allen

Dalbergia and Albizia: Plantlet Production via Tissue Culture, Karyological Evaluation, and Seed Anatomy with Scanning Electron Microscopy

Description: A publication by the National Academy of Sciences, USA (1979) outlined some of the research need for a great variety of economically important woody species whose remaining genetic resources need urgently to be collected and conserved. A viable regeneration system was established via tissue and cell suspension culture for Albizia falcataria and A. lebbeck, two important wood yielding leguminous tree species. The culture medium was standardized after several trials to obtain callus from the leaflet explants of these two tree species. The optimum use of casein hydrolysate (w/v) and coconut milk (v/v) in addition to 6-Benzylaminopurine and Indole-3-butyric acid could induce morphogenesis and somatic embryogenesis in the cultured tissue. This reports the first observation on somatic embryogenesis ofA. lebbeck using leaflets as the explants. Scanning Electron Microscopy and histological studies were done on the different stages plant development following standard techniques. Embryogenesis in suspension culture followed regeneration of plantlets in A. lebbeck. In A.falcaaria the regenerative process followed via organogenesis from the shoot buds developed on the leaf explants. After hardening the regenerated plants were transferred to the greenhouse. Some of the trees grew more than 25 feet tall within a few months outside the greenhouse. Karyotype of the three leguminous trees Albizia lebbeck, A. falcataria, and Dalbergia sissoo was analyzed. In D. sissoo, various chromosomal anomalies were observed in the cultured tissue. The abnormality indices and ploidy level varied with the age and the frequency of the subculture. In the aged culture the regenerative potential declined but was reinstated to some extent with the addition of two complex growth factors, coconut milk and casein hydrolysate. Seed anatomy of 26 species of 4 leguminous genera was studied with SEM. The main distinguishing anatomical features observed in the seed sections were uniseriate or multiseriate epidermis, epidermal projections, and number of rows ...
Date: December 1998
Creator: Ghosh, Nabarun

Role of α-Keto Acids In Cyanide Detoxification and Assimilation by Pseudomonas Bacteria

Description: Cyanide was rapidly removed when added to culture supernatants of seven different Pseudomonas. The ability to remove cyanide was correlated with the accumulation of α-keto acids (pyruvate and α-ketoglutarate). These compounds react with cyanide forming less toxic cyanohydrins, thus conferring a mechanism for bacterial cyanide tolerance. When added to growth media the α-keto acids were shown also to serve as effective cyanide antagonists. While all bacteria tested accumulated α-keto acids, only those capable of utilizing cyanide as a nutritional nitrogen source were able to metabolize cyanohydrins. In P. fluorescens NCIMB 11764, the same enzyme (cyanide oxygenase) shown previously to be involved in cyanide metabolism appears responsible for cyanohydrin transformation. Keto acid excretion is believed to represent a new mechanism of bacterial cyanide detoxification with further enzymatic metabolism of the cyanohydrins helping to explain how cyanide can satisfy the nitrogen requirement in cyanide-utilizing bacteria.
Date: December 1998
Creator: Pan, Guangliang

Regulation of an S6/H4 Kinase in Crude Lymphosarcoma P1798 Preparations

Description: Purified S6/H4 kinase (Mr 60,000) requires autophosphorylation for activation. A rabbit anti-S6/H4 kinase peptide (SVIDPVPAPVGDSHVDGAAK) antibody recognized both the S6/H4 kinase holoenzyme and catalytic domain. Immunoreactivity with p60 kinase protein, and S6/H4 kinase activity were precisely correlated in fractions obtained from ion exchange chromatography of P1798 lymphosarcoma extracts. An enzyme which catalyzed the MgATP-dependent phosphorylation and activation of S6/H4 kinase coeluted with immunoreactivity from Mono 5, but not Mono Q chromatography. Since S6/H4 kinase is homologous with rac-activated PAK65, the observation that phosphorylation is also required for activation suggests a complex mechanism for in vivo activation of the S6/H4 kinase.
Date: December 1998
Creator: Taylor, Allison Antoinette

Distribution of a Novel Gram Negative, Capsule-Forming Bacterium

Description: 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

SFE Fractionation and RP-HPLC Characterization of Aquatic Fulvic Acid

Description: The Supercritical Fluid Extraction (SFE) technique was used to fractionate Suwannee River reference fulvic acid (FA). The fractions were characterized by gas chromatography (GC) and reversed-phase high performance liquid chromatography (RP-HPLC). A SFE fractionation method was developed using stepwise gradient of supercritical CO₂ and methanol. Three FA fractions were separated. The average mass recovery was 102% with the coefficient of variation of 2.8%. The fractionation dynamics and the difference in the ratios of UV absorption to fluorescence emission indicate the real fractionation of the FA. The HPLC chromatographic peak patterns and the spectra of the corresponding peaks were almost indistinguishable. The overall results of this research support the argument that FA exhibits polymer-like molecular structure.
Date: May 1994
Creator: Shao, Peimin

Habitat Evaluation Procedures at Ray Roberts Lake: an Analysis of the Relationship with Ecological Indicators and a Study of Observer and Temporal Variability

Description: Habitat Evaluation Procedure data gathered at Ray Roberts Lake in 1989 and 1990 were analysed for temporal variability, observer variability and relationships between Habitat Units (HUs) and species density/diversity. observer variability within a group was analysed by cluster analysis and bootstrapping. Five out of 36 sites showed significant differences in Habitat Suitability Index (HSI) values within the group. A nonparametric Mann-Whitney test was used to analyze temporal variability. One of 6 sites showed a significant difference in HSI values between years. Using Spearman's Rank Correlation Coefficient, a correlation was found between indicator species density and HUs. No significant correlation was indicated between species diversity and HUs.
Date: December 1993
Creator: Wattrus, Jane M. (Jane Marie)

An Interpretation of Archaic Medical Treatises

Description: Ancient peoples did not distinguish between philosophy, religion, and science. Scientific truth did not exist apart from divine truth. Any new idea, finding, or theory was assimilated into a monolithic mythological structure. This is one of the causes of the underestimation of ancient science: it is always packaged in a myth - the method of preserving information in an oral culture. The mythological medium allowed the preservation and dissemination of hard-won, empirical, scientific knowledge through generations of preliterate peoples. The context for mythological memorization, or simply tradition, needed to be easily and naturally acquired. The ideal context was the anthropomorphic context, the ontogenic context. This is the Grand Allegory - the anthropomorphization of information. Biomyths are essentially biological texts allegorized in esoteric language.
Date: May 1993
Creator: Wagers, William D. (William Delbert)

Structural Analysis of the Genes Encoding the Oxalocrotonate Branch of the Pseudomonas putida TOL Plasmid pDKI meta-cleavage Pathway and the Expression of the xy1G Gene Product in Escherichia coli

Description: Three overlapping DNA fragments from the lower operon of Pseudomonas putida TOL plasmid pDK1, covering the xy1IH genes and downstream flanking region, were cloned into pUC19. They include a 2.8 kbp XhoI fragment, a 2.7 kbp PstI fragment and a 2.0 kbp EcoRI-HindIII fragment. They were subjected to DNA sequence analysis. The xy1I (4-oxalocrotonate decarboxylase) and xy1H (4-oxalocrotonate tautomerase) genes were found to possess coding regions of 792 and 189 nucleotides, respectively. A possible transcriptional terminator resembling E. coli rho-independent terminators was identified downstream of the translational stop of xy1H. An additional stem and loop structure was found in the intergenic region between xy1I and xy1H. The individual ORF's of the oxalocrotonate branch (xy1G, xy1I and xy1H) have been cloned into pUC18/19. The expression of the xy1G gene in E. coli was successfully assayed spectrophotometrically.
Date: December 1992
Creator: Luo, Xuebin

Immunotoxicity of Chromium Contaminated Soil in the Earthworm, Lumbricus Terrestris

Description: Objective was to assess the toxicity of chromium (Cr) contaminated soil (CS) using the earthworm Lumbricus terrestris. Specific aims were to determine: (1) survival (LC50); .(2) immunotoxicity as indicated by lysozyme activity, coelomocyte counts, secretory (SR) and erythrocyte rosette (ER) formation, and phagocytosis; and (3) compare effects of CS exposure with those of Cr spiked artificial soil (AS) . CS Cr concentration was 8.78 mg/g with 98.2% being Cr^3+ and 1.8% being Cr^6+. Using 14 d AS protocol the LC50 was 6.49% CS: AS mixture. CS concentrations of 0.5, 1.0, 2.5 and 5.0% were sublethal, whereas 6.25, 12.5, 25, 50 and 100% CS were lethal. Sublethal exposure caused no immuno- modulation. Exposure to 50% CS: AS mixture for 5 d caused reduced SR and ER formation. Exposure to AS spiked with 0.27% Cr for 5 d resulted in immunomodulation equivalent to 50% CS: AS mixtures. Results indicated the CS to be acutely toxic.
Date: May 1993
Creator: Mohammadian, Gholamreza

Evaluation of Diet, Water, and Culture Size for Ceriodaphnia Dubia Laboratory Culturing

Description: Six reagent waters, eleven diets, and two culture sizes were evaluated for culturing C. dubia. Different filtration techniques were used to prepare the reagent waters. The eleven diets were comprised of two algae augmented with eight supplements. Reproduction and growth were assessed to discern differences among C. dubia raised in mass cultures and cultured in individual cups, during which, bacterial population densities, lipid, protein, and carbohydrate concentrations of the diets were measured. Results showed that a glass-distilled, carbon filtered, deionized reagent water and a Selenastrum capricornutum- Cerophyl® diet were optimum for culturing. Mass culturing supported the highest reproduction and growth, while no correlation was found between nutritional measurements and production.
Date: December 1992
Creator: Allen, Jerry D. (Jerry Dee)

Ephippia Production, Activation, and Use of Ex-Ephippio Neonates of Ceriodaphnia Dubia as Toxicity Test Organisms

Description: Ceriodaphnia dubia is widely used as a test organism in monitoring water quality. At the present time, cultures must be continuously maintained in the laboratory. In an attempt to avoid continuous culture and maintenance, the hatching of ephippial eggs of C. dubia would provide test organisms when needed. In order to determine the parameters required for maximum hatching, approximately ninety-four thousand ephippia were exposed to a variety of conditions ranging from light and temperature regimes to drying and freezing. A low hatching yield occurred which is believed to be caused by diminished ephippia viability and/or fertility. To evaluate factors influencing the viability and fertility rate, stains of embryos were examined as were male to female ratios and mating experiments.
Date: August 1992
Creator: Poage, Duane W.

The Effect of Nine Diet and Water Combinations on the Culture Health of Ceriodaphnia Dubia

Description: Culture health of Ceriodaphnia dubia was evaluated for organisms cultured using all combinations of three foods and three waters. Criteria used to assess health of cultures included adult and neonate weights, time required to produce first broods, neonate production, adult survival, and resistance to hexavalent chromium. Diet/water combinations which produced the most neonates were not found to produce adults which were more resistant to chromium than those which produced fewer neonates. Of those evaluated, a diet of Selenastrum capricornutum and a yeast-trout chow-cereal leaf mixture was best for culturing and testing Ceriodaphnia. The best synthetic water tested was a mixture of nine parts reconstituted hard water and one part bottled mineral water.
Date: May 1990
Creator: Patterson, Paul W. (Paul William)

Responses of Pristina leidyi Smith 1896 (Naididae: Oligochaeta) to Cadmium, Vanadium, and Some Environmental Factors

Description: Concern over sediment toxicity has increased the need for toxicity test information with organisms that inhabit sediments. Oligochaetes are exposed to toxicants through feeding and direct body contact with aquatic sediments. Chronic testing with oligochaetes has historically focused on tubificids with test lengths of one year or more to encompass several generations. Most naidid oligochaetes have generation times of three to seven days and could provide chronic information in a matter of weeks. The cosmopolitan distributed naidid, Pristina leidyi, was evaluated for use as a toxicity test organism. Results of research conducted includes culture methods, effects of temperature on reproduction, growth rates in a reference sediment, acute toxicity tests, and chronic toxicity tests.
Date: May 1990
Creator: Smith, David P. (David Paul), 1956-

Interactions among Temperature, pH, and Cyfluthrin on Survival of the Fathead Minnow Pimephales promelas

Description: The 96-hr LC50 of cyfluthrin in Pimephales promelas ata temperature of 23*C and a pH of 8 was 1.08 g/L. The toxicity of cyfluthrin was inversely related to temperature and pH. A temperature of 10*C and a pH of 6 significantly decreased the 96-hr LC50 to 0.009 gg/L. Likewise, sublethal exposures to cyfluthrin significantly affected the fathead minnow's ability to tolerate high and low temperatures. Cyfluthrin compromised the fathead minnow's lower temperature tolerance (CTMin) by 60C and the upper temperature tolerance (CTMax) by 20C. Although cyfluthrin may not be present in the environment in large amounts due to its physical and chemical properties, small concentrations ( g/L) may adversely affect fish populations.
Date: December 1991
Creator: Heath, Susan M.

Site Directed Mutagenesis Of Dienelactone Hydrolase

Description: The role of individual amino acid residues of the enzyme dienelactone hydrolase was investigated. Using the polymerase chain reaction (PCR), a 1.9 kbp clcD fragment was amplified and subcloned yielding a 821 bp BamHI to EcoRI clcD subclone in the plasmid pUC19. Site-specific mutants of dienelactone hydrolase were created using mismatched oligonucleotides to prime DNA synthesis. Specifically modified proteins from mutated clcD genes (Arg 81 to alanine, Tyr 85 to phenylalanine and Arg 206 to alanine), were encoded by the mutant clones. Enzyme assays showed that dienelactone hydrolase activity of the mutants Arg 81 and Arg 206 was totally abolished. The DLHase enzyme activity of mutant Tyr 85 is greatly decreased by approximately two thirds.
Date: December 1992
Creator: Chen, Wei, 1965-

Investigation of Inhibitory Influences in Neuronal Monolayer Networks Cultured from Mouse Spinal Cord

Description: The effects of the inhibitory neurotransmitters gammaamino butyric acid (GABA) and glycine were characterized on spontaneous activity recorded from mouse spinal cord cultures. The GABA concentration which completely inhibited burst activity was chosen as a quantifiable measure of culture drug response and was used to 1) assess interculture and intraculture variability, 2) determine the influence of culture age and initial activity on GABA responses, and 3) compare the GABA responses between networks obtained from whole spinal cord and ventral half spinal cord. Results showed that 1) no significant variability existed either within or among cultures, 2) the initial culture activity directly affected GABA responses, 3) the culture age had no effect on GABA responses, and 4) there was no significant difference in GABA responses between the two spinal cord tissues.
Date: August 1992
Creator: Jordan, Russell S. (Russell Stall)

Pyrethroid Insecticide Effects on Bluegill Sunfish (Lepomis Macrochirus) and the Impacts of Bluegill Predation on Invertebrates in Microcosms

Description: Concurrent outdoor aquatic 1950 L microcosm and 0.04 ha mesocosm experiments with bluegill sunfish evaluated the ecological impact of cyfluthrin. Cyfluthrin effects were not observed on mesocosm bluegill; a slight decrease in growth was observed in the microcosm bluegill. Otolith weight to length relationships between bluegill size-classes from microcosms, local streams, and a fish hatchery revealed no differences. Our results indicated bluegill predation impacts were slight on benthic invertebrates. Extensive predation on emerging insects was observed. Microcosm bluegill impacts on zooplankton populations followed expected predation effects, resulting in larger populations of smaller taxa. Bluegill functioned as "keystone" predators for microcosm taxa and improved taxa richness for benthic colonizing invertebrates and zooplankton.
Date: May 1991
Creator: Morris, Rodney Gregg

The Effects of Long Term Modernate Ethanol Intake on Plasma Levels of ACTH, Beta Endorphin, and Corticosterone in Rats

Description: The effects of single injections and daily oral administration of ethanol on plasma levels of ACTH, beta endorphin, and corticosterone in response to cold stress were examined. The long-term experimental animals were given 0.25 ml of 28% ethanol or water orally once a day, five days a week, for fourteen months. Plasma levels of ACTH, beta endorphin, and corticosterone were lower in alcohol-treated rats as compared with water-treated rats when exposed to cold stress. The effects of a single injection of ethanol significantly elevated plasma levels of all three hormones. Mortality in sham-treated males was higher than ethanol-treated.
Date: December 1990
Creator: Breedlove, Kenneth