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open access

Interrelational Laboratory Information System for Data Storage and Retrieval

Description: The necessity for a functional user friendly laboratory data management program has become evident as the quantity of information required for modern scientific research has increased to to titanic proportions. The required union of strong computer power, ease of operation, and adaptability have until recently been outside the realm of most research laboratories. Previous systems, in addition to their high cost, are necessarily complex and require software experts in order to effect any changes… more
Date: August 1989
Creator: Gregory, Michael W. (Michael Walter)
open access

De Novo Glycogen Biosynthesis by a Glycogen Primer Complex in the Obliquely Striated Skeletal Muscle of Ascaris suum

Description: During the purification of the enzyme glycogen synthase from the muscle of the nematode Ascaris suum, approximately 70% of the glycogen synthase activity can be separated from the bulk of cellular glycogen by centrifugation for 60 min at 105,000 x . The glycogen synthase in the supernatant fraction has an Mr of 1.2 x 106 as determined by Sepharose 4B gel filtration chromatography. The glycogen synthase in this high molecular weight complex (glycogen primer complex) can be further purified by Co… more
Date: August 1987
Creator: Ghosh, Paritosh
open access

Characterization of the Self-Replicating Kirsten Murine Leukemia Viral DNA: Replication and Tetracycline Resistance

Description: This research project deals with the characterization of self-replicating Kirsten murine viral DNA. The replication of this viral DNA and tetracycline resistance conferred to bacteria by this viral DNA will be studied. The restriction endonuclease and Southern blot analysis revealed a fragment of pBR322 from the Hind III and Pst I site that is located in the 3' end of the MLV-K:E molecule. Single stranded sequencing of the two terminal ends of this fragment verified that the 3' end of MLV-K:E c… more
Date: August 1989
Creator: Najmabadi, Hossein
open access

The Suspension Cultivation of, and the use of Alternative Cell lines for the In Vitro Cultivation of, Treponema Pallidum Subspecies Pallidum

Description: This study had two objectives: to achieve suspension cultivation of Sf1Ep cells and to develop procedures for achieving the replication of T. pallidum in those cell cultures. Sf1Ep cells have been the sole cell line used for the in vitro cultivation of T. pallidum. A study was undertaken to determine if other cell lines can support growth of T. pallidum. Rabbit skin fibroblasts (RAB-9), nude mouse ear (NME) cells, and normal rebbit testis fibroblasts (RT) were compared to Sf1Ep cells for their … more
Date: May 1989
Creator: Riley, Bryan Scott
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
open access

Aspects of Fathead Minnow Reproductive Behavior

Description: Following a study of normal reproductive behavior of fathead minnows, Pimephales promelas, experiments were conducted to determine the stability/variability of behavior by sexually mature, territorial males under a variety of manipulated conditions. Collectively, these experiments indicate that although the individual behaviors of fathead minnows appear to be quite variable, the overall process, reproductive behavior, is stable.
Date: May 1988
Creator: Pyron, Mark
open access

The Effects of Diphenylhydantoin on the Lymphoreticular Tissues of the Rat

Description: A study was made of the effects of diphenylhydantoin (DPH) and the carrier solution on the spleen, lymph node, and thymus. DPH was injected i.p. at concentrations of 5 and 10 mg./100 gm. for 30 and 60 days. Hematologic effects observed were leucocytosis, neutrophilia, eosinophilia, and lymphopenia. Respiratory measurements of lymph node tissue slices were made using the oxygen electrode method. The carrier solution was found to cause a marked increase in oxygen consumption. A DPH effect on lymp… more
Date: August 1976
Creator: Gordon, Charles K.
open access

Effects of Shoot X-Irradiation on Water Uptake by Single Isolated Roots of Intact Onion Plants

Description: Using a micro-potometric method, it was ,found that X-irradiation (400 R - 18 Kr) of the shoots of the onion plant Allium cepa will produce an immediate, pronounced (200%) and reversible enhancement of the water uptake by the shielded roots. Unfiltered X-irradiation.(1200 R/min., 120 KVP, 5 ma) was delivered at right angles to the shoot. Readings were taken at 10-minute intervals before, and immediately following X-irradiation. The greatest enhancement occurred at dosages between 4.8 Kr (150%) … more
Date: December 1974
Creator: Chang, Fu-Hsian
open access

Boron Deficiency and its Associated Perturbation of Nucleotide Metabolism in Tomato Plants

Description: The effect of boron deficiency was studied in tomato plants grown hydroponically. Morphological studies showed that boron deficiency in the root system caused a cessation of root elongation, browning and thickening of root tips, the formation of branch roots close to the apex and decrease in the overall size of the root. The pyrimidine biosynthetic pathway remained intact and functional under boron limitation. The sugar nucleotide, uridine diphosphate glucose, was diminished in boron deficient… more
Date: August 1987
Creator: Dutta, Indrani
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
open access

Primary Productivity and Community Metabolism in a Small North Central Texas Pond Ecosystem

Description: Rates of primary production and community metabolism were monitored over a one year period using the diurnal oxygen method. Certain physico-chemical parameters were also measured, and autotrophic standing crops were estimated. An in-depth study was made of the phytoplankton community and various diversity indicies were calculated. Simple correlations were run between all parameters measured (biotic and abiotic), and their inter-relationships examined. Multiple linear regression analyses were us… more
Date: August 1975
Creator: Kelly, Martin H.
open access

Effects of Aging on ACTH-Stimulated Steroidogenesis in Subcellular Fractions from Rat Adrenal Glands

Description: Young, middle-aged and old rat adrenal gland steroidogenesis was measured in isolated, superfused glands and in their subcellular fractions before and after adrenocorticotropic hormone treatment. In the latter experiment, five corticosteroids were extracted from six different subcellular fractions. Superfused glands initially produced relatively high glucocorticoid levels; thereafter, production decayed asymptotically. Steroidogenesis by young and middle-aged glands was maintained at least 1.5 … more
Date: August 1982
Creator: Sawada, Tadao
open access

The Effect of Ethanol on Cardiac Activity and Brain Respiration in Chick Embryos

Description: This study concerned the effect of ethanol on cardiac activity and brain respiration in chick embryos. Ethanol dosages tested ranged from 1.0 mg to 4.0 mg/g weight. Each experiment lasted at least 150 minutes. Cardiac activity in terms of total waveform energies was integrated and printed out for plotting and analysis. The embryonic heart rates were simultaneously determined from physical graph tracings. The embryonic brain respiration was measured using a differential microrespirometer. The ef… more
Date: August 1976
Creator: Newman, James J.
open access

Effect of Calcium Channel Antagonists and Other Agents on Olfactory Reception

Description: The role of Ca++ in olfactory responses was investigated with inorganic and organic calcium channel antagonists. Electrophysiological responses to odorants were recorded from frog olfactory mucosa before and after aerosol application of different agents. Electroolfactogram responses were blocked by certain inorganic ions with the order of effectiveness Zn++ >Ln+++>Cd++>Ca++>Co++>Sr++>Mg++. Ba++ potentiated olfactory responses, and is known to potentiate calcium channel-mediated responses in oth… more
Date: August 1985
Creator: Rosick, Edward R. (Edward Rudolph)
open access

The Life History of the Mayfly Isonychia sicca (Walsh) (Ephemeroptera--Siphlonuridae) in an Intermittent Stream in North Central Texas

Description: The life history of Isonychia sicca (Walsh) was elucidated from samples collected at Clear Creek from Oct. 1976-Jun. 1978, and Elm Fork of the Trinity River from Sept. 1977-Jun. 1978, Denton County, Texas. Adaptations for existence in an intermittent stream were of primary concern. Eggs are capable of diapausing through hot, dry summers and cold, wet or dry winters. Diapause is broken in the fall after rehydration and/or in the spring. I. sicca is usually bivoltine during a Sept.-Jul. wet perio… more
Date: December 1978
Creator: Grant, Peter M., fl. 1978-
open access

Dielectric Properties of Azotobacter vinelandii in a Microwave Field

Description: A resonant frequency cavity was used to determine the dielectric properties of various preparations of Azotobacter vinelandii ATTC 12837. It was found that the bacteria investigated did interact with microwave radiation in the absence of free water. The data presented here indicate that bacteria demonstrate frequency specific dielectric properties. The techniques employed in these experiments may also be used to determine microwave spectra of other species of bacteria in different physiological… more
Date: December 1978
Creator: Hargett, John M.
open access

The Relation Between Carbon Assimilation and Biomass Dynamics in a Phytoplankton Community

Description: Production dynamics in the phytoplankton community of a mesotrophic Texas reservoir were measured weekly over a four month period using 14C incubation and ATP assay methodologies. Assimilation values of 14C ranged from 0.2 to 45 ug C 1 hr1 - . Significant positive and occasionally negative changes in biomass (i.e. viable organic carbon) were observed in short term (4 hr) in situ incubations juxtapo-sitioned with the 14C experiments; viable organic carbon production, estimated with the ATP assay… more
Date: December 1977
Creator: Wilcox, Douglas P.
open access

Food Habits, Dietary Overlap and Electivity of Non-Game Insectivorous Fishes in an Ozark Foothills Stream

Description: Etheostoma spectabile, E. punctulatum, and Cottus carolinae were sampled Mar., 1983, - Feb., 1984, in Flint Creek, Oklahoma. Immature E. spectabile ate primarily microcrustaceans, while mature fishes relied more on mayflies and amphipods. Juvenile E. punctulatum fed upon mayflies, amphipods, and Asellus. Mature E. punctulatum ate primarily mayflies, and other relatively larger prey. Cottus carolinae consumed chironomids almost exclusively in Jan. - Feb., 1984, while mayflies were predominant th… more
Date: May 1985
Creator: Todd, C. Stan (Charles Stan)
open access

Effects of Water Source, Suspended Solids, and Acclimation on Biotransformation of 2 /4-Dichlorophenoxy Acetic Acid in Aquatic Systems

Description: In recent years there has been a great deal of scientific interest in processes that affect the fate of organic chemicals in the environment. one main reason for this increased interest is due to greater environmental concern over accidental or purposeful release of these chemicals into the environment by man. A major environmental concern is the increased use of pesticides over the last few years. In the thirty years prior to 1978 the use of pesticides has increased by a factor of forty (Ridge… more
Date: August 1985
Creator: Moses, Christopher K. (Christopher Karam)
open access

Comparative Feeding Ecology of Leaf Pack-Inhabiting Systellognathan Stoneflies (Plecoptera) in the Upper Little Missouri River, Arkansas

Description: The feeding ecologies of leaf pack-associated systellognathan stoneflies were examined from 6 June 1980 21 May 1981. Species composition, seasonal abundance, nymphal growth, feeding habits and mouthpart morphology were determined for the eight dominant stonefly species. Prey preferences and predator-prey size relationships were also examined for omnivorous and carnivorous species. Foregut analysis from 2860 individuals indicated opportunistic feeding on the most abundant prey insects, usually i… more
Date: August 1983
Creator: Feminella, Jack W. (Jack William)
open access

Emergence, Growth, Drift and Microdistribution of Stoneflies (Plecoptera) in an Ozark Foothills Stream, Delaware County

Description: Adult stonefly emergence, nymphal growth, drift and microdistribution were examined in Battle Branch, a secondorder, spring-fed stream, from November, 1982 to May, 1984. Adults of 22 species emerged successionally, with specific adults present every month. Searching emergent objects and the stream margin was best for collection of winter and early spring emerging species. Sweeping the streamside and light trapping were most efficient for late spring and summer emerging species. Nymphal growth f… more
Date: May 1985
Creator: Ernst, Mark R. (Mark Richard)
open access

Size Fractionation of Metabolically Active Phytoplankton and Bacteria in Two Diverse Lentic Systems

Description: Simultaneous size fractionation of plankton populations associated with NaH^14CO_3 and ^3H-glucose uptake was employed in eutrophic Lake Texoma (Texas and Oklahoma) and oligotrophic Flathead Lake (Montana). Autoradiography was utilized to determine the role of specific microorganisms in community metabolism. Ultraplankton (0.45-10 μm) dominated plankton numbers and metabolic activity in both aquatic systems. Many of the most abundant species were not the most productive, in terms of inorganic C… more
Date: August 1980
Creator: Ellis, Bonnie K.
open access

Neuroregulation and Myosin Light Chain Phosphorylation in Ascaris Suum Obliquely Striated Skeletal Muscle

Description: Extraction and quantitation of myosin light chain two coupled with myograph recordings from Ascaris muscle perfused with calmodulin inhibitors and neurotransmitters in conjunction with their respective agonists and antagonists have been used to establish the regulation of contraction in this muscle. Densitometric tracings of isolectric focusing gels separating the regulatory light chain were used to quantitate phosphorylation in resting, contracted and flaccid muscle. These studies indicated th… more
Date: August 1985
Creator: Martin, Rex E. (Rex Edward)
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