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open access

The Physiology of Azotobacter Vinelandii Cysts

Description: The value of the adenylate energy charge [(ATP)+1/2(ADP)/(ATP)+(ADP)+(AMP)] in Azotobacter vinelandii cells was monitored during growth and germination in flask cultures. The miximal value of 0.88 was attained during mid-log phase; this declined gradually to 0.50 by late stationary phase. When these cultures were transferred to encystment media, the adenylate energy charge decreased to an average value of 0.40 as the vegetative cells encysted and remained unchanged during the next 20 days. Ency… more
Date: December 1980
Creator: Aladegbami, Solomon L.
open access

Taxonomy of the Azotobacteraceae

Description: The classification of the Azotobacteraceae to the level of genus and species has been uncertain since the studies of Beijerinck in 1901. This dissertation represents an effort to establish a system of classification more complete than the one now in use. In this study, both qualitative and quantitative taxonomy were used in order to establish a well founded classification scheme. Qualitative methods included certain important morphological and physiological characteristics, isoenzyme patterns, … more
Date: December 1980
Creator: Chang, Charles Shing
open access

Lizard Tail Autotomy: Some Aspects of its Ecology and Energetics

Description: Autotomy (self-induced loss) of body parts has evolved independently as a predator defense mechanism in several major animal phyla. The mechanism among vertebrates, including 13 of the 20 recognized lizard families, is tail autotomy. Its occurrence among the majority of lizard families offers an excellent opportunity to examine the effects of a major selective force on the ecology and evolution of a group of organisms. The research of this study was designed to examine experimentally (i) the fu… more
Date: December 1981
Creator: Dial, Benjamin Edward
open access

Chemically Active Odorants as Olfactory Probes

Description: The initial step in odor recognition by the nose is the binding of odorant molecules to receptor sites embedded in the dendritic membranes of olfactory receptor cells. Despite considerable interest and experimentation into the nature of these receptor sites, little is known of their specificity to different types of odorant molecules. This lack of knowledge partially stems from the fact that the nature of receptor proteins is most effectively studied when specific and irreversible inhibitors ar… more
Date: May 1982
Creator: Criswell, Darrell W. (Darrell Wayne)
open access

Lethal and Sublethal Effects of Hemoxidants, Particularly Nitrite, on Selected Aquatic Animals

Description: A research program was developed to investigate basic and applied aspects of toxicity, both lethal and sublethal, of hemoxidants, particularly nitrite, on fish, non-fish aquatic vertebrates, and crayfish. The major objectives of this research were to determine A) acute and sublethal toxicity of nitrite to selected aquatic organisms: 1. aquatic salamander larvae, Ambystoma texanum, 2. swamp crayfish, Procambarus simulans, 3. bluegill, Lepomis macrochirus, 4. bullfrog, tadpoles, Rana catesbiana, … more
Date: May 1982
Creator: Huey, David W. (David Worley)
open access

Postsynthetic Modifications of Glycolytic Enzymes of the Geriatric Immune System and in Fibroblasts from Premature Aging Diseases

Description: During mitogen-induced transformation of human lymphocytes, phosphoglycerate kinase (PGK) exhibits new electrophoretic forms (pl=8.5-8.9). Electrophoresis and electrofocusing showed that the new forms are not due to expression of the autosomally linked isozyme found in semen (PGK-B; pl=9.7). The multiple electrophoretic forms are the result of protease modification of sex-linked PGK-A isozyme.When peripheral lymphocytes from young persons are stimulated in vitro with phytohemagglutinin, a selec… more
Date: August 1982
Creator: Tollefsbol, Trygve O.
open access

The Effects of Freshet Turbidity on Selected Aspects of the Biogeochemistry and the Trophic Status of Flathead Lake, Montana U.S.A.

Description: The present study sought to falsify three distinct hypotheses about how the interactions of freshet clay turbidity with Flathead Lake may be affecting its trophic state: 1) that freshet-derived turbidity causes precipitation of organic detritus from the water column by flocculation and/or coagulation of dissolved and colloidal organic carbon and seston; 2) that flocculated clay-organic detritus complexes become increasingly infested with microbial biomass as they sink through the water column; … more
Date: August 1983
Creator: Stuart, Tom J.
open access

An Immunological Study of Adults with Down Syndrome

Description: The high susceptibility to infection in persons with Down Syndrome (DS) has led some investigators to explore the possibility of a defect in the immune system. Studies to date indicate no defect in humoral immunity suggesting that the defect might be in the cellular immune functions, but no specific defect has been found. Our investigation of the cellular immune system of adult DS patients was conducted by examining (1) the number and function of T-lymphocytes, (2) the phagocytic function of gr… more
Date: August 1983
Creator: White, Olivia Masih
open access

Fate of Endothall in Aquatic Environments

Description: Hazard assessment of pesticides in aquatic environments requires accurate predictions of persistence and compartmentalization. A strategy for developing confidence in predictive fate models, such as the Exposure Analysis Modeling System (EXAMS) and the Simplified Lake and Stream Analysis model (SLSA), is to test the models using carefully chosen chemicals in semi-controlled and field situations. An objective of this approach would be to isolate the variability in a particular fate process and t… more
Date: December 1984
Creator: Reinert, Kevin H. (Kevin Howard)
open access

Life History Energetics of The Red-Eared Turtle, Pseudemys scripta in North Central Texas

Description: A population of the red-eared slider, Pseudemys scripta, in north central Texas was studied from 1975 to 1980. A life history energy budget was developed for a typical individual in the population and the population dynamics were estimated. A growth model relating growth rate to mean plastron length (PL) was developed from recapture data and used to 1) establish age classes and 2) age individuals. Growth rate was highly variable in both sexes. Females grew more rapidly than males and attained a… more
Date: December 1984
Creator: Glidewell, Jerry Ray, 1945-
open access

A Study of Polynuclear Aromatic Hydrocarbon Carcinogen Transport and Deoxyribonucleic Acid Repair

Description: This investigation addresses the interrelated problems of A) Uptake and vascular transport of lipophilic chemical carcinogens, and intracellular interactions between lipoproteins and carcinogens; B) Biochemical mechanisms by which polynuclear aromatic hydrocarbon carcinogens inhibit the replicative and repair DNA synthesis in cells. The results observed in this study suggest that ingested benzo(a)pyrene (BaP) enters the gastrointestinal lymphatic drainage sequestered within lymphatic lipoprotei… more
Date: December 1984
Creator: Joe, Cheol O., 1949-
open access

Some Responses of Bacillus subtilis Spores to Glutaraldehyde

Description: Bacillus subtilis (ATCC 19659) were damaged by exposure to various concentrations of glutaraldehyde, as shown by decreased germination rates. The damage caused was repaired or otherwise obviated by the presence of sodium lactate in the holding medium. When two different salts of lactic acid were compared for ability to overcome the effect of glutaraldehyde, it was found that calcium salt of lactate was more effective than the sodium salt. The damage repair system involved l-alanine, lactate and… more
Date: May 1985
Creator: Crum, Morris G. (Morris Glenn)
open access

Immune Response of the Rat to Outer Membrane Proteins of Legionella Pneumophila

Description: Outer membrane proteins (OMPs) were recovered from eleven strains (eight serogroups) of Legionella pneumophila by sequential treatment with Tris buffer (pH 8), citrate buffer(pH 2.75) and Tris buffer (pH 8). Transmission electron microscopy revealed clearly the separation of the outer membrane from the bacteria. The development of delayed hypersensitivity was also noted by measuring the area of arythema and induration produced by intradermal injections of the MPSs from Chicago 8 strain. The adj… more
Date: August 1985
Creator: Ahanotu, Ejemihu Ndu
open access

Characterization of the Pigment-Protein Complex in Corynebacterium Poinsettiae

Description: The purpose of this study was to completely characterize the protein moiety in the caroteno complex in C. poinsettae, determine if the distribution and level of protein in the pigment-protein complex in membranes of the wild type and in a colorless mutant could account for the differences in the stability of the membrane, and to determine if this protein is common to other pigmented and non-pigmented organisms. Also, electron microscopy of cell membranes of C. poinsettiae which had been exposed… more
Date: May 1986
Creator: Ebadati, Nasrollah D.
open access

The Eosinophil and Lysophospholipase Responses in Mice Infected with Trichinella spiralis: A Role for the Lymphocyte and Macrophage

Description: The relationship among eosinophils, lysophospholipase activity and the immune response in animals infected with Trichinella spiralis was studied using in vivo and in vitro techniques. In an in vivo experiment, anti-thymocyte serum (ATS) was administered to mice infected with T. spiralis and its effects on intestinal lysophospholipase (EC 3.1.1.5.) activity, peripheral blood, bone marrow and intestinal eosinophilia were measured in the same experimental animal. The ATS caused a significant tempo… more
Date: August 1986
Creator: Adewusi, Iyabode Olukemi, 1958-
open access

The Genetics of Pigmentation in Corynebacterium poinsettiae ATCC 9682

Description: Corynebacterium poinsettiae mutant strains blocked in carotenoid biosynthesis were obtained by treatment with the mutagen N-methyl-N1-nitro-N-nitrosoguanidine. Additional carotenoid (Crt) mutant strains were obtained from a previous study conducted in our laboratory. Fifty-nine Crt mutants affected in carotenoid biosynthesis were examined by a normal phase high performance liquid chromatography (HPLC) system. Pigment extracts of Crt mutants and C. poinsettiae wild type strains were resolved by … more
Date: August 1986
Creator: Campbell, Alan L. (Alan Lee)
open access

Radial Compression High Performance Liquid Chromatography as a Tool for The Measurement of Endogenous Nucleotides in Bacteria

Description: High performance liquid chromatography was used to measure ribonucleoside triphosphates in microbial samples. Anion exchange columns in a radial compression module were used to separate and quantify purine and pyrimidine ribonucleotides. Endogenous ribonucleoside triphosphates were extracted from Escherichia coli and pseudomonas aeruginosa using three different solvents, namely trifluorocetic acid (TFA; 0.5M), trichloroacetic acid (TCA; 6 per cent w/v) and formic acid (1.0M) Extracts were assay… more
Date: August 1986
Creator: Dutta, Probir Kumar
open access

An Analysis of Respiratory Mechanisms Controlling Exercise Hyperpnea During Cycle Ergometry Conducted at Selected Workloads and Pedal Frequencies

Description: Respiratory and metabolic patterns in response to variations in exercise workload (WL) and pedal frequency (RPM) were examined in 10 healthy males. Each subject performed WLs of low (L), moderate (M) and high (H) intensity, equivalent to 25%, 50% and 75% V02 m a x at 7 pedal frequencies (40, 50, 60, 70, 80, 90 and 100 RPM). ANOVA ( 3 X 7 design) indicated that WL and RPM had independent and significant effects on all respiratory and metabolic measures; i.e., the greater the WL and RPM, the high… more
Date: December 1986
Creator: Wise, Charles Hamilton
open access

Fitness-Related Alterations in Blood Pressure Control: The Role of the Autonomic Nervous System

Description: Baroreflex function and cardiovascular responses to lower body negative pressure during selective autonomic blockade were evaluated in endurance exercise trained (ET) and untrained (UT) men. Baroreflex function was evaluated using a progressive intravenous infusion of phenylephrine HCL (PE) to a maximum of 0.12 mg/min. Heart rate, arterial blood pressure, cardiac output and forearm blood flow were measured at each infusion rate of PE. The reduction in forearm blood flow and concomitant rise in … more
Date: December 1986
Creator: Smith, Michael Lamar, 1957-
open access

Induction of Interferon Messenger RNA and Expression of Cellular Oncogenes in Human Lymphoblastoid Cells

Description: The purposes of this study was to demonstrate the induction of alpha interferon mRNA in Sendai virus-induced Namalava cells, to follow the level of alpha interferon mRNA synthesis at the transcriptional level, and to determine whether the Namalava cell line expresses the c-myc oncogene and to what degree. The amount of c-myc message deteted in Namalva cell RNA was about one-tenth that of Daudi cell RNA, whereas no difference in the amount of the c-Ha-ras message was observed between the two cel… more
Date: December 1986
Creator: Mahmoudi, Massoud
open access

New Descriptions, Intraspecific Variation and Systematic Importance of Drumming Behavior in Selected North American Plecoptera

Description: Drumming behavior is described for the first time in 33 North American Plecoptera species, and signals of an additional five species, Pteronarcys pictetii, Acroneuria abnormis, Paragnetina media, Clioperla clio and Isogenoides zionensis, are further detailed. An out-group comparison of behavioral characters in all 104 world species whose drumming is known showed that the behavior is more advanced in the Arctoperlaria Group Systellognatha than in the Group Euholognatha. In general, tapping, mono… more
Date: December 1986
Creator: Maketon, Monchan
open access

Roles of Calcium Ions and Cyclic AMP in Olfactory Transduction

Description: The roles of Ca2 + and cAMP in olfactory transduction were explored using agents which affect calcium channels and second messenger systems. These agents were applied at certain calculated final concentrations onto olfactory epithelia of urethane-anesthetized frogs (Sana PiPlens) by two-sec aerosol spray. During extracellular recording, saturated vapors of isoamyl acetate were delivered every 100 sec in 0.3 sec pulses to produce an electroolfactogram (EOG). Inorganic cations that block inward … more
Date: December 1986
Creator: Winegar, Bruce D. (Bruce David)
open access

Characterization of the Pigment-Protein and Pigment-ester of Xanthomonas Campestris Pv. Juglandis

Description: The objectives of this project were to develop a high performance liquid chromatographic method for separating the pigment esters mixture, to determine the locations of the pigment moiety in the isolated esters using pholosiphases, and to characterize the pigment-protein complex and determine its distribution in other bacteria. Saponification of the two pigment esters 1 and 2 with aqueous KOH yielded two free pigments on TLC plates developed by two solvent systems. The fasters moving of these t… more
Date: May 1987
Creator: Lawani, Leonard Olu
open access

Resistance and Morphology of Azotobacter Vinelandii Grown on Dialyzed Soil Agar

Description: The objectives of this research were to identify the form of Azotobacter as it exists in situ in the soil; to compare its resistance to that of laboratory grown cysts typical of those described in the literature; and to compare its resistance to that of cells grown on dialyzed soil agar. In addition, the morphology of the cells grown on dialyzed soil agar was examined by light and electron microscopy and then compared to the cysts grown on n-butanol Burk's medium. Dipicolinic acid and oxygen up… more
Date: May 1987
Creator: Gogu, Sudhir Reddy
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