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Population Studies of Ulmus Crassifolia in Flood-Plain Forests of Denton County, Texas
The problem with which this investigation was concerned was the comparison of cedar elm populations in different stands along creeks in Denton County, Texas, and the relationship of certain population parameters to various substrates present at stand sites, Parameters investigated eluded average basal area, basal-area density, transect-segment density, intertree distance, lateral distance, frequency, diameter breast-high, diameter breast-high size-class distribution, and immature-tree density. Variations among populations of Ulmus crassifolia Nutt were noted and analyzed in terms of soil particle size and existing community conditions.
A Preliminary Report on the Effect of Roentgen Rays on the Formed Elements of Avian Blood
This problem consists primarily in determining the numerical value of the leukocytes after different amounts of roentgen rays had been applied to the subjects. The Atomic Energy Commission set up a problem concerning the effects of roentgen rays on the fertility in chickens, and grants were given to two institutions to study this. The blood work in this paper was an off-shoot from one of these five fertility grants.
Presence of Krebs Cycle Intermediates in Primary Mycelia of an Actinomycete
The purpose of this study is to determine the presence or absence of a typical Krebs cycle metabolism in the primary mycelia of an aquatic streptomycete.
Properties of Normal Rat Kidney Cells Transformed by a Temperature-Sensitive Mutant (LA31) of Rous Sarcoma Virus
The basis of this investigation is to characterize growth property differences in normal versus virally transformed cells. Using a temperature-sensitive mutant of Rous sarcoma virus, the cells' transformation state is regulated by the growth temperature; at 33°C the cells are transformed, while at 39°C the cells have normal characteristics. The morphology of NRK cells is elongated and fibroblastic; when transformed the cells are rounded. Normal cells grow to a monolayer and stop, while transformed cells grow to saturation densities greater than just a monolayer amount. Transformed cells can form foci when grown in mixture with normal cells. Normal cells must be in contact with the culture vessel in order to grow, but transformed cells lack anchorage dependence for growth.
Protective Effect of Specific Heterologous Anti-Mouse Tumor Serum
The principal purpose of this work was to determine the effect of immunized guinea pig serum upon the survival time of tumor infected mice, and to make a correlation between this effect and the complement titer.
Purification and Characterization of Ascaris Suum Aldolase : An Initial Phylogenetic Study of Aldolases
An efficient purification procedure of Ascaris suum muscle utilizing ion exchange column chromatography has been developed.
Qualitative and Quantitative Chromatographic Determination of Muscle Myosin Production in Control and Chronically Accelerated Chick Embryos
The purpose of this investigation was to employ newly improved qualitative and quantitative chromatographic techniques to obtain purified myosin from 1 G and 3 G chick embryos and to determine if muscle myosin production either follows or precedes the unparallel bone growth during chronic acceleration as reported by several investigators.
A Quantitative and Qualitative Bacterial Analysis of the Sewage Disposal System of Perryton, Texas
This investigation had for its purpose the determination of first, the inefficiency of the Perryton, Texas, sewage disposal plant proper; and second the potential effectiveness of a lagoon now used to complete the sewage purification; and consequently, offset an apparent health hazard. The problem, as pursued, has consisted of first, the collection of sewage samples from the six stations listed in Table 1 over the period of time from September 23, 1949 to May 14, 1950; second, a quantitative analysis of each sample in order to determine the number of bacterial organisms present; third, a qualitative analysis of each sample in order to determine more expecially the presence of members of the genera Aerobacter, Escherischia, Salmonella and Shigella; and fourth, an attempt to evaluate the potentialities of the natural purification factors of the lagoon.
Rectal Temperatures of the Cotton Rat, Sigmodon Hispidus (Rodentia : Cricetidae)
This investigation has been concerned with determining the extent to which a small mammal, the cotton rat, may become acclimated to environmental temperatures, and the influence acclimation has upon a population. The study was also designed to determine if acclimation effects on a population can be seen in individual rats.
Relationship of Certain Fungi to Azotobacter in Nitrogen-Free Media
Azotobacter and various fungi were grown together in nitrogen-free media. Maximal fungal growth in the medium used was possible only at the expense of Azotobacter cells and growth was always accompanied by acid production. When the medium reached a pH of 2, the bacterial cells were aggregated on fungal hyphae and the culture fluid appeared to be free of Azotobacter. Aspergillus niger grew well at the expense of viable bacteria and other fungi grew well on heat-killed cells of A. vinelandii. Members of the genus Hormodendrum, although not causing significant decrease in pH, were also able to clear turbid cultures of Azotobacter. However, clearing, which involved the attachment of bacteria to fungal hyphae, was dependent on acid production by the fungi. Bacterial aggregation was followed by hyphal attachment, bacterial inactivation, and finally, bacterial cell lysis.
Resistance of Some Soil Bacteria to Pentachlorophenol and Sodium Pentachlorophenate
The purpose of this study was to see if any soil bacteria were able to use pentachlorophenol or sodium pentachlorophenate either aerobically or anaerobically as a sole carbon source, to see if any soil bacteria could survive in high concentrations of sodium pentachlorophenate, to determine the maximum concentration of sodium pentachlorophenate which permitted the growth of some soil bacteria, to see the effects of varying concentrations of sodium pentachlorophenate on the growth curves of soil bacteria capable of growing in its presence, and to see if any soil bacteria could degrade sodium pentachlorophenate.
Serological Characteristics of Morphologically and Biochemically Similar Streptomyces Species
It is the purpose of this investigation to test for serological characteristics of six Streptomyces species which exhibit identical and/or very closely similar morphological and biochemical characteristics.
A Serological Study of the Aerobic Actinomycetes
The purpose of this work is to find an adequate immunizing procedure for aerobic actinomycetes and a suitable method of testing for antibodies produced. Some of the factors which influence the antigenicity of the organisms, and the demonstration of specific antibodies have been included.
Some Effects of X-irradiation on the Plasma Corticosterone, Adrenal Weights, and Differential Leukocyte Count in the Rat
The purpose of the present study was twofold: (1) to determine if X-irradiation can be considered a direct stress agent, and if so, to what extent it differs from other stressors; and (2) to further elucidate the role of the adrenal cortex in the radiation syndrome by determining the more immediate responses of this system to X-irradiation.
Some Physiological Characteristics of Vitreoscilla stercoraria
The purpose of this study was to elucidate some of the physiological characteristics of V. stercoraria with regard to oxygen requirements, growth, nutritional requirements, pH effects on growth and growth factors.
Some Relationships between Certain Aquatic Actinomycetes and Bacillus Cereus
The purpose of this investigation is to determine if there was a metabolic relationship between the actinomycetes and the gram positive, spore-forming becilli in surface waters, and, if such a relationship was evident, to relate the association to the disappearances of typical actinomycete tastes and odors from waters.
Spring Food Habits of Corydalus Cornutus L. in the Brazos River, Texas
The objective of this study was to determine the kinds and numbers of food organisms consumed by Corydalus cornutus, and to investigate its periodicity of feeding during the spring months in the Brazos River, Palo Pinto County, Texas. A total of 468 larvae were collected at two-week intervals from February 29 to May 14, 1971. Larvae were taken at opportunity during three periods of the day, 6am.-12pm., 12pm.-6pm., and 6pm.-12am. A total of 23 different food items was observed in the 121 stomachs containing food. An expedient method of dissection of the digestive tract is included.
The Stoneflies (Plecoptera) of Oklahoma
Distributional data and taxonomic keys art presented for thirty-four species of Plecoptera known to occur in Oklahoma. Ten species are new records for the state. Descriptions are provided for two species new to science, Zealeuctra cherokee and Isoperla brevis, and for the previously unknown male of Strophopteryx cucullata Frison and female of Helopicus nalatus (Frison).
Studies of Mouse Hypersensitivities
Having considered the data collected thus far concerning immediate and delayed hypersensitivity reactions in the mouse, the experimentation following is devised essentially to follow the pattern of Crowle in the production and testing for immunoresponse. Instead of using the normal solvent, that is, acetone, this work is also intended to partially evaluated the use of dimethyl sulfoxide as a solvent for the contact allergin, dinitroflurobenzene.
Studies of Odor-Producing Actinomycete Response to Selected Geosmin Concentrations
The purpose of this investigation was to explore how geosmin, an odorous compound produced by certain algae and actinomycetes, may affect the growth of a selected, odor producing actinomycete of the genus Streptomyces.
Studies on the Bacterial Flora of Milk, Ice Cream, and Beverages in Denton, Texas
The purpose of this study is to observe the frequency of occurrance of members of the colon group in various brands of milk, milk products, and soft drinks marketed in the city of Denton, and to determine the total number of bacterial organisms occuring in these products from week to week.
Studies on the Nutrition of Rhodospirillum Rubrum
The purpose of this study has been to examine the nutritional requirements of Rhodospirillum rubrum and, on the basis of the results, develop a culture medium which could be use to promote more rapid and abundant growth facilitating the laboratory cultivation and observations of the properties so exhibited.
Studies on the Purification and Phosphorylation of Phosphofructokinase from Ascaris suum
A new procedure has been developed to concentrate the phosphofructokinase from muscle of Ascaris suum with minimum loss of activity. By utilizing this method, 50 ml fraction was concentrated to a final volume of 3 ml in about 1.5 h without loss in enzyme activity. The concentrated enzyme had a specific activity of 64 units per mg. Ascaris muscle-cuticle was incubated in 50 1M solutions of either acetylcholine, serotonin, y-aminobutyric acid, levamisole, or saline alone. Phosphate analysis of the isolated phosphofructokinase from each incubation revealed that the enzyme contained the following moles of phosphate per subunit: 2.9 (acetylcholine), 2.2 (serotonin), 2.0 (y-aminobutyric acid), 1.5 (levamisole), and 3.4 (salne alone). The present study did not establish a direct correlation between degree of phosphorylation and phosphofructokinase activity. Phosphofructokinase from muscle of Ascaris suum appears to contain several phosphorylation sites, and one of these sites is required to be phosphorylated in order for the enzyme to exhibit maximum activity under physiological conditions.
A Study of a Selected Group of Science Related Characteristics of Non-Science Majors
The purpose of this study is to gather information related to the characteristics of two groups of undergraduate non-science majors; namely, those students who once considered science as a career and subsequently changed to a non-science major and those who have never considered a career in science. It is frequently observed that children in the elementary school have an intense interest in science. One of the principal concerns of this study is how and for what reasons has the interest in science changed between elementary school and college? It is also the purpose of this study to gather information related to the attitudes of these college students toward the science courses they have had in high school and toward their science teachers. In attempting to arrive at an answer, the group who once considered a science career and those who have never considered an occupational choice in a field of science will be compared in the following areas: 1. General information such as sex, age, size of high school attended, rank within their graduating classes, college classification and military experiences. 2. Occupations and hobbies of parents. 3. Experiences which may influence attitudes toward science such as elementary school science, high school science courses, high school science teachers, attitudes toward science requirements, high school courses liked most, high school courses liked least, and membership in science clubs. 4. College science courses completed. 5. Extent of the interviewees' present interest in science, Finally, the circumstances surrounding the tentative choice of a science career by those who once considered such a career will be discussed.
A Study of Aryl Hydrocarbon Hydroxylase in Cultured Human Lymphocytes
Aryl hydrocarbon hydroxylase activity was studied in cultured human lymphocytes using 3-methylcholanthrene, 1,2- benzanthracene, and 4'-bromoflavone as inducers. The substrates used to run the 60 minute assay were benzo(α)pyrene and diphenyloxazole. At the optimum bromoflavone concentration for induction of aryl hydrocarbon hydroxylase, the induced enzymatic activity compared favorably with that of aryl hydrocarbon hydroxylase induced by 3MC in a 96 hour lymphocyte culture using BP as the assay substrate. The whole cell human lymphocyte system was found to have as much or more activity in 20 ml vials using Joklik's-Modified Minimum Essential Medium at a pH optimum of 7.5 with no co-factor added as did the Roswell Park assay system. The whole cell assay showed that levels of aryl hydrocarbonhydroxylase inducibility in lumphocytes from smokers and non-smokers varied without regard to the subjects' smoking habits. The assay system also indicated that intact lymphocytes generate a similar group of benzo(α)pyrene metabolites as that produced by a hepatic microsomal preparation from C57B1/6J mice.
A Study of Plankton Dilution in Source Streams Compared with that of Lake Dallas Proper
This study was a comparative study of Plankton of Lake Dallas and the three main source streams. Based on the analysis of data, which was presented relative to the organisms taken from the lake and from the source streams, the results obtained are discussed, the Plankton seem to be largely autogenetic in Lake Dallas, the source streams Elm Fork and Clear Creek form a dilution process.
A Study of Selected Factors Influencing Science Majors Toward Science Careers
"The purpose of this study is to gather information concerning some factors which may have operated to influence science majors in North Texas State College toward science careers."--4.
A Study of Selected Factors Related to Permanency in Science Teaching
The purpose of this study is to gather information related to some factors which are considered to be characteristic of science teaching; to attempt to identify some elements of permanency in science teaching; and to analyze some relationships between the results of the above two criteria with the view of establishing some factors which may be useful as predictors of permanency, or indicative of patterns of permanency, in science teaching.
A Study of Some Congenital Anomalies of the Teeth
Anomalies of the teeth include a variety of expression such as: anodontia, hyperdontia, peg teeth. opalescent dentine, mottled enamel, and other imperfections of the teeth. This paper is concerned primarily with anodontia in human subjects, although other abnormalities of interest are mentioned. Insufficient datum is the principal difficulty encountered in determining the mechanism and means of transmission in human genetics. Small families, slow breeding, and inability to subject humans to experimentation account, in part, for this difficulty. The lack of reliable data is the second major difficulty in determining the mode of transmission. Often normal or unaffected members of a family are forgotten due to insignificance placed on them--thus an untrue pedigree is the result. The fact that one must rely on information from one or two members of a family lends itself to error. Therefore, an absolutely accurate determination of Mendelian ratios in human genetics would be impossible. This error, however, can be reduced by the gathering and compilation of large numbers of family pedigrees from which calculations can be made and results determined which will reveal the mode of transmission of various hereditary traits. With this view in mind, this paper is presented, first, to add several more cases to the literature, and, second, by analysis of the pedigrees to determine the possible modes of transmission of these anomalies.
Taxonomic Analysis of Marine Actinomycetic Isolates
Though this current study was initiated independently and was not a test laboratory for the taxonomic sub-committee's evaluative program, the problem outlined in this treatise was also designed in an effort to test certain characteristics of the actinomycetes of both a biochemical and morphological nature. This problem employed methods that might absolve or establish certain criteria for taxonomic use in the group of actinomycetes.
Teratogenesis in Inbred Strains of Mice
The purpose of this investigation is to determine if differences exist between four inbred strains of mice in susceptibility to the drug thalidomide.
Toxicity Studies of Aquatic Actinomycetes
Since Actinomycetes have been isolated from finished public drinking water, it is believed that the organisms are unaffected by the chlorination and flocculation of water treatment plants and pass as spores through the filters into the general distribution system. For this reason it was deemed imperative to study the toxic effects of these organisms.
Transferrin Inheritance in the Pigeon, Columba livia
This study investigated transferrin inheritance in homing pigeons (Columba livia), using discontinuous acrylamide gel electrophoresis on rivanol treated serum.
Transport of Viable Dissemules of Algae and Protozoa by Selected Diptera
This research was designed primarily to determine whether and to what extent several species of Dipteria (true flies) carry viable dissemules of algae and or Protozoa "in-flight."
Treatment of Akr Mouse Leukemia with Specific Heterologous Antiserum
This thesis has been an attempt to observe the role antibodies play in extending the life span of tumor infected Akr mice.
Treatment of Akr Mouse Leukemia with Specific Rabbit and Mouse Antiserum
This work is concerned with a study of the role of complement and antibodies in the serum of rabbits and of a non-susceptible strain of mice in the protection of Akr mice injected with active Akr tumor cells.
The Use of Similarity Indicies to Assess the Spatial Differences of the Phytoplankton Communities in Lake Ray Roberts, Texas
A study of the phytoplankton communities of Lake Ray Roberts was conducted at three sampling sites on two sampling dates during the summer of 1995, assessing both community structure and chlorophyll a concentrations. Eight similarity indices were then used to characterize and compare the communities of these sites. Both community similarity and chlorophyll a concentrations were evaluated using a minimum detectable difference equation to determine the amount of change that must occur in these parameters in order to be deemed statistically significant. The Bray-Curtis Index was shown to be the most adequate index evaluated, and was subsequently used in conjunction with bootstrap analysis to determine the similarity between the three sampling sites.
Variations in Soil Fungi of Ten Representative Soils of Denton, County, Texas
This study attempted to examine representative soils of Denton County in an effort to determine seasonal and soil type variations in the fungous flora both quantitatively and qualitatively.
The Vegetation and Habitat Factors of Red River County, Texas
The aim of this study has been to measure some of the ecological factors in a series of plant habitats and their relation to the existing vegetation in selected twenty soil types of Red River County, Texas.
A Vegetative Key to the Grasses of Erath County, Texas
"The orientation of this study began with a collection of the grasses of Erath County during their flowering periods. Collections were made in the Spring and Fall of 1950 and 1951 to obtain both vernal and autumnal grasses. Identifications were made from the grass floras previously mentioned and checked against specimens in the herbarium of North Texas State College for verification. In addition, the list was checked by W.A. Turney, Conservationist, United States Department of Agriculture of Dublin, Texas. Finally, the list was compared with that prepared by W.M. Cory for the plant areas of which Erath County is a part. On the basis of the above identifications, a critical study of the vegetative characteristics was made and a key based on these features prepared. The width of the blad and characteristics of the ligule, roots, culms, and sheaths were used to distinguish each of the eighty-six specimens found in the collection area. A drawing was made of the longitudinal section of the juncture of the blade and the sheath of each grass. This diagnostic section includes the collar, ligule, a part of the blade and sheath, and auricles, if present."-- leaf 5.
X-irradiation and Drug Effects on Ventral Root Potentials in Cat Spinal Cords
The purpose of the present study was sixfold: 1. To study the effects of x-irradiation on spinal cord activity. 2. To study the effects of CNS drugs on spinal cord function as reflected by changes in the ventral root potentials. 3. To ascertain whether one can alter the observed spinal response to ionizing radiation by applying CNS drugs prior to, during, and following x-irradiation of a given spinal cord segment. 4. To shed some light on the role of higher brain centers on spinal reflexes. 5. To shed some light on the loci of radiation insult to the spinal cord. 6. To establish evidence for a possible drug-irradiation interaction in mammals.
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