The effect of oxidation-reduction potential (Eh) and oxygen concentration on the outgrowth of Clostridium botulinum type E spores was studied. An airtight flask containing electrodes for continuous measurement of Eh and pH and attached tubing for the exchange and mixing of various gases (i.e. prepurified nitrogen, anaerobic carbon dioxide, hydrogen, oxygen) were utilized. Prereduced media and anaerobic procedures were employed to insure controlled conditions and reproducible results. Eh measurements were made of Trypticase Soy Broth containing several concentrations of the following reducing agents which are listed in what was found to be the order of their reducing intensities: sodium formaldehyde sulfoxylate, 2-mercaptoethanol, cysteine hydrochloride, sodium thioglycolate, and ascorbic acid. Outgrowth of C. botulinum type E spores was shown to be directly related to a low Eh and a low concentration of added reducing agent. Outgrowth and Eh changes were measured in the electrode vessel described above for several growth conditions. Eh levels in the media were poised by sparging prereduced media with nitrogen gas or 0.1% oxygen in nitrogen gas or by sparging with nitrogen gas in oxidized media (media which was autoclaved under air). Under uninhibited growth conditions there were no significant growth differences between the oxidized (Eh = -80 mv), oxygen poised (Eh = -80 mv), and reduced (Eh = -190 mv) media. However, inhibition by sodium chloride (3.5% and 4.0%), hydrogen ions (pH 5.11 and 5.05), and sucrose (30% and 35%) revealed an increased lag phase and a decreased maximum absorbance for growth in the oxidized medium compared to growth in the reduced medium. Media poised by dissolved oxygen also exhibited retarded growth when compared to the reduced media. The addition of exogenous hydrogen gas to the media reduced or eliminated the growth and lag time differences described above for sucrose inhibition. It was shown that the Eh drop observed during growth of the test organism probably occurred during emergence and outgrowth of the spores and not during germination. In addition, this drop was coincident with the production of metabolic hydrogen gas by the organism. Data indicated that the presence of hydrogen gas in the medium would reflect an artificially low potential as a result of the local ionization of the hydrogen at the platinum tip of the Eh measuring electrode. This effect may obscure any actual reducing in Eh. An increased lag phase was observed when a small inoculum (10² spores/ml) was used compared to a large inoculum (10⁴ spores/ml). This difference in lag was similar to that observed between the reduced and the oxidized or oxygen poised media. It is hypothesized that the variations in growth are due to a distribution of sensitivity within each spore inoculum population to adverse conditions (e.g. low pH, high sucrose, high salt, high Eh). / Ph. D.

The purpose of this study was (1) to determine the degree of agreement among three role-defining groups concerning their perception of actual and ideal role behavior ascribed to the Director of Adult Education and (2) to determine the degree of agreement within each role-defining group concerning their perception of actual and ideal role behavior ascribed to the Director of Adult Education. The three role-defining groups were Deans of Instruction, Directors of Student Personnel Services, and Directors of Adult Education. The six role areas associated with the position of Director of Adult Education were: Planning, Organizing, Promoting, Supervising, Managing, and Controlling. A two-part questionnaire consisting of 58 role behavior statements, divided among the six role areas, was mailed to each of 48 members of the reference group. Forty-three responded to the questionnaire. Each individual was asked to select the category for each statement that best reflected his perception of the regularity with which the director actually performed the behavior. This same request was made regarding his perception of the desirability of the behavior. The results of the study indicated a significant degree of disagreement between the three role-defining groups in the areas of promoting, supervising, and managing for actual role behavior. A significant degree of disagreement existed between the three role-defining groups in the area of managing for ideal role behavior. Directors of Adult Education perceived a significant degree of difference between actual and ideal role for planning, organizing, supervising, and controlling. Deans of Instruction perceived a Significant degree of difference between actual and ideal role behavior for planning, promoting, supervising, and controlling. Directors of Student Personnel Services perceived a significant degree of difference between actual and ideal role behavior for planning, organizing, promoting, supervising, and controlling. Based on the findings of the study, the following recommendations were made: (1) the study should be replicated to add validity to the research procedure and methodology; (2) similar studies should be conducted to identify new and emerging roles of directors of adult education; (3) a comparative study would appear useful to determine if similar patterns of behavior emerge regardless of the setting. Other recommendations included: communication workshops within the institution, other studies that would include additional role-identifiers, technical institutes, four-year colleges, and more variables, and comparative studies dealing with specialized personnel within the field of adult education. / Ed. D.

An analysis is presented of the main, superharmonic, subharmonic, combination and internal resonances in a weakly nonlinear system having many degrees of freedom. The system has cubic nonlinearities, modal linear viscous damping and is subject to harmonic excitations. The method of multiple scales, a perturbation technique, is used to develop a unified method for the study of the various resonances. The effects of an internal resonance are explored in depth. The first approximation obtained by the method of multiple scales extracts the dominant features of the response and expresses them in terms of elementary functions. It is shown that in the absence of internal resonances, the steady-state response can contain only the modes which are resonantly excited. In the presence of an internal resonance, modes other than those that are resonantly excited can appear in the response. The usefulness of the method developed in this work in providing clarity and insight into nonlinear phenomena is illustrated by applications to the nonlinear vibrations of beams and circular plates. Numerical examples show that the results obtained by the first approximation compare favorably with the results obtained by a numerical integration of the governing differential equations. The numerical examples indicate that a significant transfer of energy can take place from the highest mode involved in the internal resonance to the lower modes but not vice versa. / Ph. D.

The movement of algal nutrients was studied in the Occoquan Watershed. During the period April through September 1973, weekly water samples collected by the Occoquan Monitoring Laboratory were split for chemical analysis and algal growth potential (AGP) assay. Variation in AGP observed between stations indicated that the major source of algal nutrients was sewage treatment plants in the Bull Run portion of the Occoquan Watershed. Chemical analyses, likewise, indicated that the Bull Run waters were highest in phosphate and nitrate concentration. Both phosphate and nitrate concentrations were found to correlate highly with AGP for green and blue green test species. For the green alga Selenaetrum capricornutum, the chemical nutrient most highly correlated with AGP was nitrate, whereas for the bluegreen alga Anabaena flosaquae, total phosphate gave the highest correlation coefficient. A graphic analysis of AGP versus nitrate-nitrogen concentration indicated that Selenastrum yield does not increase with nitrate concentration when orthophosphate concentration is less than 0.010 mg-P/liter. At concentrations greater than this, however, nitrate appears to control the Selenastrum AGP. A similar analysis of Anabaena AGP versus nitrate-nitrogen indicated that nitrate concentration does not affect Anabaena AGP unless the total phosphate concentration is greater than 0.150 mg-P/liter. At total phosphate concentration greater than 0.250 mg-P/liter a definite stimulation of Anabaena yield due to nitrate concentration was observed. The weekly changes in chemical nutrient flux were examined through spring and summer seasons. The nitrate and phosphate loadings of Bull Run, which receives sewage treatment effluent, were found to be high and relatively constant throughout spring and summer. The agricultural region of Occoquan Creek, however, showed high nitrate loadings only during periods of stormflow. At baseflow, Occoquan Creek nutrient loadings were found to be insignificant. A decrease in nutrient content of the Occoquan Creek tributary was observed during summer due to the influence of a small recreational lake in Occoquan Creek upstream from the reservoir. Finally, analysis of material and energy transfer between water strata in the stratified reservoir indicated that hypolimnetic nutrients do not enter the epilimnion at a rate sufficient to cause algal bloom conditions. Storm events were observed to cause mixing of the reservoir and so provided the nutrient concentration necessary for algal blooms. It is suggested that removal of phosphates from all sewage treatment effluent in the Occoquan Watershed will reduce the frequency of blue green algal blooms and allow more effective control with copper sulfate. / Ph. D.

The purpose of this study was to illustrate by using a Planning-Programming-Budgeting System how a centralized technical processing agency could eventually aid in lowering costs and in improving the efficiency and effectiveness of technical services operations, and provide interactive bibliographic means which would permit users to maximize the utilization of the available resources of the learning resource centers in West Virginia's community colleges. Prior to engaging in the application of the components of PPBS to the simulated technical services processing center, a data collection process and a comparative analysis review of the existing technical services processing costs and operating procedures in the learning resource centers were performed. Results of these two investigations provided the data base for determining the comparative costs between the existing processing cost per unit and the PPB System alternatives, and the latitude and compatibility were established concerning which alternatives would be appropriate for the existing technical services processes. Basic policy statements, program structure, program memoranda, program financial plan, and special analytic studies were the components of PPBS which were delineated and used interdependently with the program objectives and alternatives of the technical services processing center. Primary thrust of lowering the unit cost per processed item and providing better service for the users of the learning resource centers was continually re-emphasized. The two recommended alternatives evolving from the PPB System were: (1) the Ohio College Library Center System was recommended for the acquisitions and cataloging functions, and (2) a telefacsimile transmitter-receiver system was recommended for the interactive bibliographic functions. Projected cost per processed item for the OCLC System during the first operating year was approximately $6.171 less than the average cost for processing per item by the learning resource centers during 1973-74. The cost savings would be expected to be greater each ensuing year. With the cost per processed item being reduced or remaining almost steady each year during a period in history when such a financial result would be in direct contrast to inflationary practices, the accountability of the planners of the technical services processing center would be enhanced. The telefacsimile transmitter-receiver system would provide a means for relaying bibliographic information and facsimile copies of various material for users among the three learning resource centers. It would also complement the acquisitions and cataloging functions by providing a method for forwarding ordering and cataloging information to and from the processing center. / Ed. D.

The purpose of this study was to design and validate an instrument suitable for ascertaining student opinions about various economic issues. An initial pool of statements concerning various economic issues was compiled from several sources. This pool was then reduced to seventy-five items. Development of the instrument was then initiated through a pilot study. The seventy-five item pool was submitted to a group of students with no prior formal exposure to economics and not currently enrolled in an economics class. The results were then factor analyzed. The result was a forty item instrument measuring opinions concerning five economic issues. Next, this forty item survey was tested to determine if the instrument would ascertain changes in student opinions after the completion of an introductory economics course. The methodology employed was the use of two groups of students--control and treatment. Each group was administered a pretest and a posttest. Eight student characteristics were considered as independent variables. As a result of the treatment, students changed their opinions slightly concerning selected economic issues. The instrument was sensitive in detecting these small changes in opinions. The instrument also revealed that these opinion changes were related to the following student characteristics: (1) degree of dogmatism; (2) marital status; (3) college attended; and (4) whether or not a student intended to transfer to a senior college. / Ed. D.

The interest in year-round education has grown considerably since 1964, but the associated research and evaluation has not kept pace. The present status of how teachers' attitudes have been affected by changing the school calendar from a traditional nine-month term of operation to year-round operation has been widely debated. Prior information on this topic is almost non-existent. The need for such information has been evident by the increasing number of teacher organizations, school boards, lay persons, and school administrators seeking information from the National Council on Year-Round Education regarding year-round education as it relates to teachers' attitudes. This study was formulated to provide evidence related to: How selected personal and situational variables relate to teachers' attitudes toward year-round education and how can variations in those attitudes be measured. An assessment instrument, the Teacher Attitude Inventory On Year-Round Education, was designed to determine the relationship between teachers’ attitudes on year-round schools and selected personal and situational variables. Principals of participating schools provided faculty lists which made up the total population of the study and also indicated a contact teacher in the school that would receive, distribute, collect, and return the completed inventories to the researcher. Of these lists, 30% or 800 teachers were included in the sample. The teachers were from 103 operational 45-15 year-round schools in the United States. Returns were received from 75.73% of the schools and 69.50% of the teachers who agreed to participate. Data was electronically transferred to cards and analyzed using the following computer programs: (1) BMDO4D, Frequency Count; (2) BMDO2R, Stepwise Regression; and (3) BMDO8M, Factor Analysis. The analyses were performed on the IBM 370/158 computer at Virginia Polytechnic Institute and State University. The assessment instrument designed for this study was found to be unidimensional, measuring a single major attitudinal construct relating to year-round education. Four sub constructs relating to year-round education were determined that reflected teachers' attitudes toward: (1) Calendar/Program, (2) Administration, (3) Student Welfare, and (4) Teacher Welfare. The internal consistency of the instrument was determined to be 0.5565. A significant relationship was found between the following personal and situational variables and teachers’ attitudes toward year-round education: (1) favorability toward year-round schools, (2) morale, (3) fatigue, and (4) quality of the educational program related to the subconstruct on Calendar/Program; (5) providing adequate support staff related to the subconstruct on Administration, and (6) fringe benefits related to the subconstruct on Teacher Welfare. None of the personal and situational variables related to the subconstruct on Student Welfare. The following personal and situational variables were determined not to have any significant relationship to attitudes expressed by teachers toward year-round education: (1) type of school calendar utilized prior to the year-round calendar, (2) number of students enrolled, (3) population density of the school-community setting, (4) sex, (5) age, (6) marital status, (7) total teaching experience, (8) teaching experience in year-round school, (9) teaching level, (10) calendar preference, (11) student-teacher ratio, (12) level of professional attainment, (13) degree of program development participation, (14) professional association membership, (15) options on contract length, (16) work participation option, (17) vacation option, and (18) salary adjustment. / Ed. D.

A constitutive equation for whole human blood was developed using a power law functional form. This power law equation contains two parameters, the consistency index and the non-Newtonian index for the fluid. Viscometric data, utilizing a cone and plate viscometer, were obtained from anticoagulated blood samples of known hematocrit levels and chemical compositions. A multiple regression technique with apparent viscosity as the dependent variable was used to determine the consistency index and the non-Newtonian index. A model including only the shear rate as the independent variable was found to be lacking any substantial degree of significance. When hematocrit was added as an independent variable, the degree of fit increased considerably. Of the chemical variables examined, the least significant, as far as effects on viscosity is concerned, were the plasma lipids. The proteins, fibrinogen and globulin were found to have a much greater effect on viscosity than the protein, albumin. The best constitutive equation involving the chemical composition of blood was found to include the shear rate, the hematocrit level, and a variable which is the sum of fibrinogen and globulin. This model produced a statistically significant increase in the correlation between experimental and theoretical data compared with the best two variable model. / Master of Science

We begin this paper with a survey of characterizations of pseudocompact spaces and relate pseudocompactness to other forms of compactness such as light compactness, countable compactness, weak compactness, etc. Some theorems on properties of subspaces of pseudocompact spaces are presented. In particular, conditions are given for the intersection of two pseudocompact spaces to be pseudocompact. First countable pseudocompact spaces are investigated and turn out to be maximally pseudocompact and minimally first countable in the class of completely regular spaces. We define a pseudocompactification of a space X to be a pseudocompact space in which Xis embedded as a dense subspace. In particular, for a completely regular space X, we consider the pseudocompactification αX = (βX - ζX) U X. We investigate this space and in general all pseudocompact subspaces of βX which contain X. There are many pseudocompact spaces between X and βX, but we may characterize αx as follows: 1) αx is the smallest subspace of βX containing X such that every free hyperreal z-ultrafilter on X is fixed in αx. 2) αx is the largest subspace of βX containing X such that every point in αX - X is contained in a zero set which doesn't intersect X. The space αx also has the nice property that any subset of X which is closed and relatively pseudocompact in X is closed in αx. The relatively pseudocompact subspaces of a space are important and are investigated in Chapter 4. We further relate relative pseudocompactness to the hyperreal z-ultrafilter on X and obtain the following characterizations of a relatively pseudocompact zero set: 1) A zero set Z is relatively pseudocompact if and only if Z is contained in no hyperreal z-ultrafilter. 2) A zero set Z is relatively pseudocompact if and only if every countable cover of Z by cozero sets of X has a finite subcover. In the next chapter we consider locally pseudocompact spaces and obtain results analogous to those for locally compact spaces. Then we relate pseudocompactness and the property of being C* - or C-embedded in a space X. Included in this is a study of certain weak normality properties and their relationship to pseudocompact spaces. We develop two types of one-point pseudocompactifications and investigate the properties of each. It turns out that a space X is never C* -embedded in its one-point pseudocompactification. Also one space has the property that closed pseudocompact subsets are closed in the one-point pseudocompactification while the other may not have this property but will be completely regular. We present survey material on products of pseudocompact spaces and unify these results. As an outgrowth of this study we investigate certain functions which are related to pseudocompactness. / Doctor of Philosophy

Aspartate transcarbamylase (carbamylphosphate:L-aspartate carbamyltransferase, E. C. 2.1.3.2) from Chlorella sorokiniana was stabilized in vitro by uridine and UMP with 0.04 mM uridine and 0.05 mM UMP giving half maximal stability. Positive cooperative effects on stabilization were observed for UMP but not uridine. The enzyme was stabilized at all temperatures between 2° and 50°, but in the absence of the nucleotide the enzyme was both cold and heat labile and had a temperature stability optimum of 32° for an incubation time of 90 min~ The enzyme was more stable in glycylglycine buffer than in Tris-HCl buffer. The enzyme was inhibited by uridine and UMP, but concentrations of 1.6 mM uridine or 2.6 mM UMP were required for 50% inhibition. Sensitivity to inhibition was diminished by ammonium sulfate fractionation or multiple passages through a French pressure cell. The loss of sensitivity to inhibition may be due to breakdown of the enzyme into subunits or breakdown of a multienzyme complex of pyrimidine enzymes. An assay for activity of carbamyl-P synthetase (E. C. 2.7.2.5), a suspected component of the multienzyme complex, was developed for Chlorella. Neither aspartate transcarbamylase nor carbamyl-P synthetase was sedimented by centrifugation at 100,000 x g for 5.5 hours. Either a multi-enzyme complex does not exist, the complex is of low molecular weight, or the complex was destroyed during preparation of the cellular material. Synchronous Chlorella cells were used to study the regulation of aspartate transcarbamylase during the cell cycle. Under certain culture conditions (constant light intensity per cell and nitrate as the nitrogen source) the enzyme accumulated in a step pattern with the step increase in enzyme accumulation occurring during DNA replication. This pattern is consistent with two hypotheses: The structural gene is transcribed only during the S-phase, or the structural gene may be transcribed continuously if the enzyme is unstable and either under a constant level of repression or free from repression. In the second case, if the enzyme were synthesized and broken down at the same rate, the enzyme would accumulate only when the gene dosage increased as a result of DNA replication. When culture conditions were altered in such a way as to cause the light intensity per cell to oscillate during the cell cycle, accumulation of the enzyme began before the onset of DNA replication. Therefore, the structural gene for aspartate transcarbamylase is not expressed constitutively, and enzyme accumulation is not restricted to the S-phase as predicted by the first hypothesis. In another experiment, the nitrogen source was changed from nitrate to ammonium, and the effective light intensity was increased but held constant during the cell cycle. The enzyme accumulated in a continuous pattern and DNA in a step pattern, again demonstrating that DNA and enzyme accumulation are not obligately coupled. When DNA synthesis was inhibited by 74%, by the addition of 2'-deoxyadenosine, there was no corresponding effect on enzyme accumulation. / Doctor of Philosophy