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Actinoplanes Philippinensis: Effect of Carbon Sources on Zoospore Production
Actinomycetes are able to utilize a great variety of carbohydrates, like sugar. The particular kind of sugar and its concentration has decisive effect on the growth of microorganisms. The proper nutritional media aids also in the production of spores. Based on this generalization, that the growth and sporulation of microorganisms are greatly influenced by the nature and the concentration of carbohydrates, an attempt has been made to study Actinoplanes philippinensis with respect to this influence.
The Adaptability and Present Status of Andropogon Ischaemum L. in Denton County, Texas
This investigation has been made with reference to the adaptability of Andropogon ischaemum, King Ranch bluestem, to various soils, various slopes, and various erosion conditions in Denton County.
Assimilation of Inorganic Nitrogen by Aquatic Actinomycetes
It was the purpose of this investigation to present laboratory data concerning the assimilation of inorganic nitrogen by the aquatic actinomycetes. The strains of aquatic actinomycetes under consideration represented a cross section of those currently under culture at North Texas State University.
The Autecology of Celtis Laevigata in Flood Plain Forests of Denton County, Texas
This thesis describes the present nature of one facet of some of the flood plain forest stands in Denton County, Texas. The specific purpose was to demonstrate the presence or absence of difference between the Celtis laevigata (commonly known as the hackberry, southern hackberry or sugarberry) populations in stands on Denton Creek and Elm Fork of the Trinity River.
Bacteriological Studies of the Campus Drinking Fountains of North Texas State Teachers College Denton, Texas
"In order to gain an adequate idea of the sanitary condition of the drinking fountains on the North Texas State Teachers College campus, it was found necessary to approach these bacteriological studies from a seasonal point of view."--1.
A Bio-Chemical Comparative Study of the Plankton in Lake Dallas and Pecan Creek
The purpose of this investigation is to compare the dissolved and suspended organic material in Lake Dallas to that coming into the lake through Pecan Creek.
The Biological Elimination of Phenols in the Effluent of a Wood Preserving Plant
The removal of phenols from the waste waters of wood preserving plants has always presented problems. The purpose of this paper is to investigate the possibility of employing a biological system to reduce the phenol content of effluent from these plants.
Comparative Chemistry of Thermally Stressed North Lake and Its Water Source, Elm Fork Trinity River
To better understand abiotic dynamics in Southern reservoirs receiving heated effluents, water was analyzed before and after impoundment in 330 ha North Lake. Macronutrients, metals, and chlorinated hydrocarbons were measured. Concentrations of nutrients and metals in sediments were quantified in this 2 yr study. River water prior to impoundment contained 16 times more total phosphorus, and supported 23 times more Selenastrum capricornutum cells in an algal assay than reservoir water. The reservoir has essentially no drainage and since evaporation is high, the concentrations of many dissolved solids have increased since the reservoir was filled in 1958. North Lake is now phosphorus limited. Apparently altered chemical equilibria have caused precipitation or adsorption of phosphorus with calcium and iron.
A Comparison of Predicted and Actual Trophic Status of Lake Ray Roberts, Texas Based on Chlorophyll A
Two years before impoundment, the trophic status of Lake Ray Roberts was predicted by applying the total phosphorus input into the Organization for Economic Cooperation and Development (OECD) eutrophication model. Predicted mean summer epilimnetic (MSE) chlorophyll a of Elm Fork arm, Isle duBois arm and Main Body were in the eutrophic category of the OECD model. Observed MSE chlorophyll a two years after impoundment of Elm Fork arm, Isle duBois and Main Body had not reached their predicted means and were at the mesotrophic-eutrophic boundary of the OECD model. Six years after impoundment, observed MSE chlorophyll a for Main Body, was closer to its predicted mean and in the eutrophic category of the OECD model. Six years after impoundment, Elm Fork arm was the most productive area of Lake Ray Roberts. Observed means of chlorophyll a, total phosphates, suspended solids and turbidity were often highest in the Elm Fork arm. Wastewater effluent from Gainesville and Valley View, TX, had an impact on productivity in Elm Fork arm.
A Comparison of the Carbon Dioxide and Oxygen Rate of Change Methods for Measuring Primary Productivity
The purpose of this study was to demonstrate the variability of oxygen and carbon dioxide rate of change methods for measuring primary productivity and respiration in an aquatic environment.
Composition and Distribution of the Vegetation in Farm Pastures in Denton County, Texas
This investigation has for its aim the determination and the evaluation of the vegetational composition in certain farm pastures in Denton County, Texas.
Degradation of Phenolic Acids by Azotobacter Species Isolated from Sorghum Fields
Sorghum plants excrete phenolic acids which reduce subsequent crop yields. These acids accumulate in field soil by combining with soil and clay particles to form stable complexes which remain until degraded by bacterial metabolism. The amount of phenolic acids in soil samples were obtained by gas chromatography measurements, while Azotobacter populations were obtained by plate counts in 40 sorghum field samples from Denton County, Texas. One can conclude that increasing the Azotobacter population in the soil increased the degradation rate of phenolic acids proportionally. It is proposed that seed inoculation will introduce selected strains of Azotobacter into the soil. The presence of Azotobacter should increase crop size in subsequent plantings.
Distribution of Phosphates in a Sewage Plant and its Receiving Waters
The purpose of this paper is to detail the distribution and quantity of soluble phosphates in an activated sludge plant, its discharge creek, and receiving reservoir. The resultant analyses and comparison of data should provide some better understanding of the fate of phosphorus in a Southwestern waterway system.
The Dynamics of a Planktonic Microcrustacean Community in a Small North Central Texas Pond Ecosystem
Seven species of planktonic microcrustacea were identified from the North Texas State University Golf Course Pond. Total adult microcrustacean community density, biomass and biocontent, and seasonal cycles of each species were compared with northern populations. Species diversity and evenness indices were highest in summer and lowest in spring. Variations in microcrustacean density showed a positive correlation with density of phytoplankton. Temperature had a direct effect on metabolic rates of two species of copepods. Metabolic rates of pond species were lower at common temperatures than those of northern populations. An estimate of annual energy flow through the pond ecosystem showed cladocerans contributed the greater percentage of total energy to the next trophic level.
Edaphic Factors Which Control the Distribution of the Common Mesquite, Prosopis Chilensis (Molina) Stuntz in Denton County, Texas
This paper deals with the distributional outgrowths of Prosopis chilensis (Molina) Stuntz, the common mesquite, in Denton County, Texas.
Evaluation in Soil Moisture in Soil and Water Conservation Practices in Denton, Texas
This investigation has attempted to show that soil and water conservation practices do increase the amount of soil moisture in five of Denton County, Texas soils: Denton clay, Durant clay, San Saba clay, Kirvin fine sandy loam, and Tabor fine sandy loam.
Evaluation of a Constructed Wetland to Reduce Toxicity from Diazinon at the Pecan Creek Wastewater Treatment Plant, Denton, TX
The City of Denton Pecan Creek Wastewater Treatment Facility has periodically failed effluent toxicity testing. A Toxicity Identification Evaluation has determined that Diazinon in the effluent is contributing to the observed toxicity. Chlorpyrifos is also implicated as a factor. The City of Denton constructed a half acre experimental wetland to remove Diazinon related toxicity. Results from spiking and microcosm experiments indicate that the wetland can reduce the Diazinon.
In Vitro Determination of the Cellulose-Decomposing Rates of Twelve Denton County, Texas Soils
In this study twelve types of top soil were collected under aseptic conditions. The cellulose-decomposing rates of these were compared in order to determine the relative rates in the cellulose-decomposing potential of the microorganisms involved. Furthermore, this investigation is designed to acquire pertinent information on the rate at which natural cellulose materials are returned to available plant food.
The Incidence of Colon Bacteria on the Hands of North Texas State Teachers College Students
This investigation has for its aim the determination, in a measure, of the degree of personal sanitation existent among students at North Texas State Teachers College, Denton, Texas.
The Incidence of Escherichia Coli and other Coliform Organisms on Seventy-One Samples of Fresh Fruits and Vegetables Purchased from Eight Grocery Stores in Denton, Texas
This investigation has for its aim the explanation of the incidence of colon bacteria on a number of food samples purchased in grocery stores of Denton, Texas, by an analysis of correlative sanitary factors.
An Investigation of Microbial Antagonism in Ten Denton County, Texas Soils
This thesis is concerned primarily with the growth and detection of soil microorganisms in ten Denton County, Texas, soils antagonistic to a specific gram-positive and a specific gram-negative bacterial organism.
The Isolation and Identification of Micro-Organisms from Spoons of Public Eating Establishments in Denton, Texas
This investigation deals with the isolation and identification of bacteria found on selected samples of spoons in various eating establishments in the vicinity of Denton, Texas.
The Larval Lipids of the Chironomid Midge Glyptotendipes Barbipes (Staeger)
This problem was concerned with determining the total lipid content and individual lipid composition of the larvae of a local chironomid, Glyptotendipes barbipes (Staeger).
Microflora Found in a Selected Group of Food Products Enclosed in a Protective Wrapper
The purposes of this study are, first, to determine relative numbers and predominant types of bacterial organisms in the various food products studied; second, to evaluate the efficiency of the paper coverings of these foods; and third, to determine whether these products are potential sources of food poisoning.
Microflora of Frozen Fruits and Vegetables Dispensed from Grocery Stores in Denton, Texas
This investigation was carried out in order to determine whether or not blanching and freezing tends to reduce the incidence of bacteria, particularly those of the coliform group, and also the yeasts and molds.
Parasites of the Cricket Frog, Acris Crepitans, of Denton County, Texas
The purpose of this study was threefold. The literature concerning parasites of A. crepitans was to be brought up to date. Contributions to the general body of knowledge pertaining to the parasitic fauna of host specimens of A. crepitans and specifically those found in Denton County, Texas, were to be made. Finally, specimens found parasitizing host specimens of A. crepitans were to be preserved and classified.
The Phototropic Properties of Lactuca Ludoviciana (Nutt.) DC. and Silphium Laciniatum L.
This paper deals with certain phases of phototropic properties of two exceptional plants, the pertinent behavior of each being decidedly individualistic and in remarkable contrast to that of herbaceous plants in general. The prickly lettuce, Lactuca ludoviciana (Nutt.) DC. and the rosinweed, Silphium laciniatum L., two common Denton County, Texas, plants, have been selected for this study.
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.
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.
A Qualitative Survey of the Airborne Algae, Protozoa, and Bacteria at the Denton Sewage Treatment Plant
This study had a three-fold purpose. First, it was decided to determine if algae and protozoa were emitted to the air at the Denton sewage treatment plant. The information obtained could be of future importance in the fields of algal and protozoan ecology and public health. Second, it was decided to make a survey of the airborne bacteria at this plant. Some researchers have described bacterial air contamination at similar sewage treatment plants, but the one in Denton has not been studied. Third, it was hoped that in this research some relationships could be found between the bacteria and the algae and protozoa in the air in the vicinity of the sewage aeration basin. It was hypothesized that pathogenic bacteria were carried in the air with these other organisms.
A Quantitative and Qualitative Bacterial Analysis of Pecan Creek
Since Pecan Creek receives sewage wastes from an obviously inadequate disposal system, it seemed possible that it could receive pathogenic bacteria. The fact that these might be present in numbers sufficient to cause epidemics, provided the proper natural vectors were present, stimulated an interest in and the pursuance of this study.
Sanitary Aspects of the Swimming Pool of North Texas State Teachers College, Denton, Texas
This investigation was conducted in order to show that insanitary conditions may exist in the swimming pool at North Texas State Teachers College provided the proper precautions are not taken; and, in contrast that this pool can be sanitary and entirely safe when operated and used according to the necessary sanitary specifications.
Seasonal Survey of Actinomycetes in Twenty Denton County, Texas, Soils
This investigation has had for its aim a further study of actinomycete flora of twenty Denton County, Texas, soils. The problem has evolved itself into, first, a seasonal analysis for the number of actinomycetes in each of the twenty soils; second, a determination of the types of soils that contain the greatest number of actinomycetes in each cultivated and uncultivated land; third, a determination of soil moisture and pH; and fourth, an attempt to correlate these factors with the number of actinomycetes found in each soil type.
Seasonal Variations in Microflora of Four Denton County, Texas, Clay Soils
This investigation has for its aim the confirmation of the correlation between soil moisture and the microflora of soils, and a lesser relation between the soil temperature and the microflora. The soils used in this study are typical clay soils of Denton County, Texas. The samples were taken from virgin pasture lands and analyses made monthly or semimonthly. The wide seasonal variation of temperature and rainfall afford a good opportunity for this study.
Seasonal Variations in the Microflora of Four Denton County, Texas, Sandy Soils
This investigation has been made to see whether there is a correlation between microorganisms present and the water content and temperature of four Denton County, Texas, sandy soils.
A Solution for High Bacterial Counts in a Local Dairy, Denton, Texas
It is the aim of this investigation to determine through routine checks if the bacterial count in the milk from Brooks Dairy Company is high and if so to determine the source. If it is found that the laboratory plate counts are unnecessarily high, it is the further purpose of this paper to make recommendations for improvements in the quality of milk produced by this dairy plant.
Studies of Fungal Antagonism in a Norfolk Fine Sand, Denton County, Texas
This investigation has had for its primary purpose the noting of the incidence of antagonists as occurring in a Denton County, Texas, Norfolk Fine Sand. A further interest has been the determination of the effect of these antagonists upon known beneficial soil organisms.
Studies of the Bird Life of Denton County, Texas
"As a means of defining the purpose of the problem, the following objectives were considered: (1) to list the species of birds observed in Denton and neighboring counties; (2) to assign a descriptive status to each species; (3) to estimate the relative abundance of each species (4) to annotate the list with data from other sources, when additional data provide a more accurate and complete description of the status of the species in Denton County; (5) to designate the section of the county in which each species was most frequently observed; and (6) to briefly summarize the changes in bird populations during the period 1950-1956, and to suggest some hypotheses which help explain these changes." -- leaf 6.
A Study of a Branchiobdellid from Denton County, Texas
In this study, branchiobdellids were collected from crayfish captured from two adjacent sites in Denton County, Texas. Identification of the branchiobdellid, Cambarincola vitrea Ellis, was first made and then work was extended to include several topics of ecological interest.
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 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.
Survival and Growth of Bacteria in Chlorine Treated Water
In this problem, an attempt was made to determine the fate of various species of bacteria which had previously been isolated from other sources when inoculated into Denton tap water.