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

This study was concerned with the assessment and analysis of legal information needs of the major administrators in the public higher education system of the District of Columbia. The study further sought to provide a model Request for Proposal (RFP) with a performance specification suitable for inclusion in a public contract which ultimately would result in a study and handbook of the identified legal aspects. The administrators' needs and desires for legal information were assessed through a questionnaire survey. The questionnaire was divided into three section emphasizing: a. What information was generally known. b. What additional information was needed. c. What information was desired. Results of the survey indicated that there was a generally low awareness of the more popular aspects of college and university law. However, the administrators appeared to be generally aware of the specific legal aspects pertaining to the instruction or classroom activity. Most of the administrators felt that they were not equipped with sufficient legal information to make decisions on matters with legal implication that could withstand a challenge in court. Constitutional rights, employment contracting, fiscal administration, and policy conflicts were viewed as the most frequent problem areas, while accreditation and tenure problems were viewed as the least frequent. The survey also resulted in a priority listing of legal topics for which additional information was desired. The survey results were used as a basis for developing a draft outline of legal information topics and sub-topics for inclusion in a study and handbook. A panel of experts in higher education administration and law was effective in producing a final qualified outline. Using the final topic outline, a draft model RFP, containing a performance specification, was designed. A second panel, comprised of experts in contracting, reviewed, modified and validated the model RFP as being usable to actually obtain the required services through a public contract, to conduct a study and produce a handbook with emphasis upon the District of Columbia public higher education system. It was concluded that: a. Administrators of the public colleges in the District of Columbia do want and need additional legal information. b. Administrators of the public colleges in the District of Columbia can specifically identify their needs and desires for legal information. c. Expressed or identified legal information needs can be converted into a public contract performance specification. Key recommendations for further study included the development of objective evaluation criteria applicable to performance contracts and the actualization of the study results by the appropriate offices of the District of Columbia Government. / Ed. D.

John L. Holland has developed a theory which states that people can be characterized by their resemblance to each of six personality types: realistic, investigative, artistic, social, enterprising, and conventional. Holland further indicates that the environments in which people live can be characterized by their resemblance to six model environments which correspond to the six personality types. Finally, the pairing of persons and environments leads to predictable outcomes relative to vocational choice, vocational stability and achievement, educational choice, and susceptibility to influence. The purpose of this study was to determine the extent to which Holland's model of occupational classification could be applied to an inner-city high school population. In order to determine the applicability of Holland's model to the population being tested, four hypotheses were formulated. 1. There are significant relationships between the occupational classifications of Holland's model when applied to an inner city high school population. 2. There are significant relationships between the intercorrelations of the occupational classifications of Holland's national sample and the intercorrelationR of the occupational classifications of the present study. 3. There is a significant relationship between the rank ordering I of the intercorrelations of the occupational classifications of Holland's study and the rank ordering of the intercorrelations occupational classifications of the present study. 4. There are dominant personality types in an inner-city high school population as measured by the Vocational Preference Inventory. The subjects for the study were 492 high school sophomores (218 male, 274 female) from Region I of the Baltimore Public·School System. To test the first hypothesis, data collected by the VPI were treated by the correlation program BMDO3D. This treatment resulted in a correlation matrix. The data were then displayed on a hexagonal model. The relationships among the scales on the hexagon were treated by Spearman and Kendall correlation coefficients. The results indicated that the relationships were significant at the .001 level. The second hypothesis required a comparison of the hexagon which resulted from testing the first hypothesis with Holland's hexagonal model. The results revealed higher correlations among the six scales of the present study than for Holland's study. The third hypothesis was tested by treating the rank ordered correlations from the present study and Holland's model with the Spearman coefficient of rank correlation, The results indicated that the two rank orderings were significant at the .01 level. The fourth hypothesis 'Was tested by using the SPSS program Codebook. The results yielded means and standard deviations for male and female subjects. 'l'his made it possible to determine the three highest variables for male and female subjects. The dominant variables for the male subjects were Realistic, Enterprising, and Conventional, and for female subjects, social, Artistic, and Conventional. The results of statistically treating the data from this study revealed similarities between Holland's findings and the findings of this study. Thus, it could be suggested that the VP! is an appropriate instrument to use with inner-city high school students. / Ed. D.

The amount of change in self-concept during the first term of attendance of 267 students in a rural, Appalachian community college was explored. Sixteen subscales of the Tennessee Self-Concept Scale (TSCS) were employed, in a pre-test/post-test design, as the indicator of change in self-concept. Students were stratified by assignment to one of two groups within 11 demographic variables: Curricula, Age, Sex, Marital Status, Employment Status, Fathers I Education Level, Fathers' Occupation Level, Student Financial Aid, Special Services Program for the Disadvantaged, Level of Choice of the Community College, and Enrollment Status. The null hypotheses were tested by multivariate analysis of covariance (MANCOVA), univariate analysis of covariance (ANCOVA), and calculation of simultaneous confidence intervals. Adjusted mean scores of variable groups were compared through these statistical procedures, in order to discover if there were significant differences in self-concept change at an alpha level of .05. Significant differences were not noted at the .05 level, dictating a failure to reject the null hypotheses which stated that there would be no significant differences in the level of self-concept between the groups comprising the demographic variables. It was noted, however., that there were trends toward significant differences (p less than .10). The Total Positive Score subscale revealed significant differences at this level between 14 variable groups. The subscales of Self-Satisfaction, Physical Self, Distribution Scores, Identity, Personal Self, Social Self, Total Variability, and Self Criticism also yielded significant differences at this level., although between a lesser number of variable groups. Trends toward significant differences (p less than .10) were most evident on the variables of Age, Sex, Employment Status, Student Financial Aid, and on the comparison of the variable group combinations of Curricula/Fathers' Education Level. Exploration of self-concept change of the total sample., on each TSCS subscale, revealed a minor change, in a positive directio., on each subscale. Although self-concept is believed by many to be a major determinant of behavior and performance., findings of this study implied that self-concept development was not a principal classroom objective. It was also believed that since all subjects were commuting students., the environment which was external to the campus could have served as a counter-influence on individual self-concepts. Further investigation of this problem. using the TSCS and other self-report instruments. was recommended. / Doctor of Education

Research was initiated in the spring of 1972 to evaluate the effects of the Smith Mountain Pumped Storage Project on the spawning success of centrarchid fishes in the lower impoundment, Leesville Lake. Hydroelectric power generation operations at the Smith Mountain Dam power plant create high water velocities with daily flow reversals, and water level and temperature fluctuations in Leesville Lake. Water levels in Leesville fluctuate as much as 3.5 m (11 ft) per day and 4 m (13 ft) per week during spawning periods of centrarchid fishes. In addition, daily intrusions of subsurface water from Smith Mountain Lake into Leesville Lake during periods of power generation average less than 20 C in temperature. At night and on weekends, surface waters from Leesville Lake are pumped back to Smith Mountain Lake. These project operations create three fluctuating, relatively unstable sections in Leesville Lake; a cool upper reservoir zone, a mid reservoir temperature mixing zone, and a warmer lower reservoir zone. Centrarchid fishes were collected from the three reservoir zones in Leesville Lake and gonads were examined. Generally, gonadal maturation and the presence of fish in spawning condition occurred earliest in the warmer lower zone, later in the mid reservoir, and last in the cooler upper zone of Leesville Lake during 1972 and 1974. During 1974, trained divers located and inspected 2010 centrarchid fish spawning nests in Leesville Lake. Based on a constant unit of diving effort, 40 percent of nests occurred in lower Leesville, 57 percent in mid, and about 3 percent in the upper reservoir zone. High water velocities restricted spawning activity in the mid and upper reservoir zones almost entirely to cove areas. Water velocities in lower Leesville had negligible effects on the distribution of spawning activity. A stepwise regression model indicated that water velocities during power generation at Smith Mountain Dam was the single most important factor affecting the distribution of spawning nests in the main lake. Vertical distribution of centrarchid fish spawning nests suggested that adjustment to the spawning depth had occurred in response to the fluctuation in water levels. Nearly 40 percent of all spawning nests in Leesville Lake were located 0.3 to 1.5 m below minimum pool elevation or about 4. 5 m below maximum pool level. Laboratory and field studies were conducted to evaluate hatching success of bluegill (Lepomis macrochirus) eggs under controlled water temperatures and exposures to air. Average hatching success increased as hatching temperatures increased from 16 to 28 C. Hatching success of naturally spawned bluegill eggs exposed during night and daytime hours in natural spawning nests in Leesville Lake decreased with increased exposure to air. SUCCESS, a computer-implemented mathematical model using data generated in this study, indicated that the average spawning success of bluegill would be about two times higher in the lower zone than in upper Leesville Lake. Predicted estimates of spawning success of bluegill for the entire reservoir were about 31 percent. Based on the current levels of exploitation, natural spawning success of largemouth bass and bluegill in Leesville Lake appears adequate to maintain the densities of these centrarchid fish stocks. / Ph. D.

In 1974 the state of Virginia began a legislative study of the methods utilized to fund teacher aides and developed accreditation standards for elementary and secondary schools permitting employment of teacher aides. Prior to this time, the Virginia State Department of Education had no state program for training or certification. However, it had suggested (in 1969) limited personnel policies for selection of teacher aides, which proved to be a stimulus for several local school districts in the state to develop limited personnel policies relating to the employment of teacher aides. This study was designed to present descriptive data concerning areas of existing local teacher aide personnel policy. The study also delineated, as normative data, those policy areas considered important for inclusion in future local and state guidelines. A study was made of the teacher aide policy handbooks received from an inquiry addressed to the directors of 141 local Career Opportunities Programs in the United States. Similarly, a study was made of the status of teacher aides as indicated in responses elicited from the Department of Certification and Teacher Training in each of the 50 states. With the data received from these studies, a three-part survey instrument was developed which contained 40 policy items under each of three major areas of concern, "current local policy," "opinion for future local policy," and "opinion for future state policy." An additional item was included to ascertain legal status and opinions relative to certification. The instrument was mailed to all (131) of the local district superintendents in Virginia, selected (24) administrative and instructional personnel in the Virginia State Department of Education, and all (67) of the teacher aides who were members of the Department of Teacher Aides, Virginia Education Association, in 1974. The rate of return for superintendents was 92.4 percent, for state department personnel, 87.5 percent, and for teacher aides, 61.2 percent. Statistical procedures of frequency distribution and percentage were utilized in analysis of the data. Of those items which are currently part of local policy, 15 were unanimously recommended for inclusion in both future local and state guidelines. Inclusion of 40 policy items was recommended by a majority of the superintendents for future local policy, while state department personnel recommended 38 and teacher aides, 34. For inclusion in future state policy, a majority of superintendents recommended 35 policy items, state department personnel, 22, and teacher aides, 33. The study revealed that for Virginia instructional teacher aides there should be developed a comprehensive set of local and state policy guidelines for training, certification and related personnel practices. These were seen as means of providing for shared accountability between state and local policymakers in those areas of funding and permanacy of the instructional teacher aide position. Policy guidelines for certification, training and related personnel areas have further implications for the individual instructional teacher aide. These were seen as means for providing greater job security, higher salaries, status, and availability of financial assistance for pre-service and in-service career training programs. / Ed. D.

In the relatively young sub-discipline of Public Choice, there are a number of theoretical models predicting the type of equilibrium that would be expected in the production of goods and services in the public sector. These models arrive at a number of different conclusions; but one major class of models predicts that public sector output will cater to the demands of the median voter, while another class of models predicts that the amount of public sector output will exceed that level most preferred by the median voter. More information can be generated about the nature of equilibrium in the production of public education than for most other goods and services produced in the public sector, because of the existence of millage issue elections that are held in many states. Two aspects of millage issue ·elections are emphasized in this analysis. First, millage issue elections . act as a constraint on the behavior of school boards, since the school board cannot enact a millage rate without first receiving the approval of the voters. Second, millage issue elections act as a revealed preference experiment, since voters are being asked to state their preferences on the millage issue presented in the referendum. These two aspects of millage issue elections generate information about the nature of equilibrium in the production of public education, and provide the basis for using millage issue elections as a vehicle for studying the nature of equilibrium in the production of public education. A model for interpreting the results of millage issue elections is developed, followed by a survey of institutional differences in public school finance from state to state. Some empirical propositions are forwarded, based on the hypothesis that there is a general tendency for school expenditures to exceed the level most preferred by the median voter. Two empirical analyses fail to support the propositions, but are in agreement with the results that would be expected if public education were being produced at close to the level most preferred by the median voter. / Ph. D.

A study was made to ascertain the mechanism by which ortho-positronium reacts with nitroaromatics in solution. These reactions are two to three orders of magnitude faster than expected by simple pickoff. Conjugation of the nitro group with the aromatic ring was found to be a necessary condition for this behavior. The rate constant for each of these reactions was measured in suitable solvents over a wide temperature range, 200-500°K. Distinct departure from the Arrhenius law was found. In general, the rate constant increased linearly with increasing temperature up to a point, and then decreased linearly as the temperature was raised further. The following mechanism is postulated: Ps + M [stacked right and left arrows with k₁ above and k₋₁ below] PsM [right arrow with k₂ above] M + 2γ. Ortho-Positronium reacts with the nitroaromatic, M, to form a complex in a reversible step. The complex may either decompose into a positronium atom and nitroaromatic molecule or it may go on to annihilate the positron. A steady-state concentration ot the complex is assumed and the observed rate constant for the process is K_obs = k₁k₂ /(k₋₁+ k₂) The two limiting cases are: (1) k₂ >> k₋₁ causing k_obs = k₁ . Typical Arrhenius behavior is expected and observed in this region, and (2) k₋₁ >> k₂ causing k_obs = K_EQk₂ . In this region H_EQ + E_a(2) <O and the observed rate constant decreases with increasing temperature. This corresponds to a stable but temperature sensitive PsM complex. An approximate molecular orbital study has been made to study the possible existence of positron and positronium complexes with a select number of organic molecules. The CND0/2 approximation is used for all electronic integrals and for electron positron Coulomb integrals. The core Hamiltonian matrix elements for the positron were estimated by combining the Wolfsberg-Helmholtz and Cusachs-Cusachs approximations. This approach shows that the positron should become bound to the molecules. Using the same criteria, the formation of stable positronium complexes is more improbable. The calculated binding energies are strongly dependent on the value of the Wolfsberg-Helmholtz proportionality constant for positrons. / Doctor of Philosophy

A procedure has been developed for solving flutter problems of simply supported laminated plates using linear small deflection theory. The plate construction may be arbitrary as long as it satisfies the assumptions of linear small deflection theory. For such plates, the bending and extensional governing equations are coupled and have cross-stiffness terms which do not appear in classical plate theory. The coupling and cross-stiffness terms occur as a result of the lamina principal directions (fibers) not coinciding with the neutral surface of the plate. The extended Galerkin method is used to obtain approximate solutions to the governing equations where the aerodynamic pressure loading used in the analysis is that given by linear piston theory with flow at arbitrary cross-flow angles. Flutter solutions were obtained for typical symmetric, angle-ply, and general laminated composite plates, and a limited parametric study was conducted. The parameters studied include the number, orientation, and orthotropy of the lamina; the plate length-width ratio; the inplane normal and shear loads; and the cross-flow angle. In addition, flutter solutions for several composite stiffened aluminum plate designs were obtained to determine the most flutter resistant design. The bending-extensional coupling and the cross-stiffness terms both have a large destabilizing effect on the flutter of unstressed laminated plates, but increasing the number of laminas, reducing the lamina orthotropy, and stacking the laminas in the"best" order reduce the destabilizing effect. For a square plate, aligning the fibers with the direction of flow (x-axis) results in the highest flutter stability, but for a plate with a length-width ratio of 2, large improvements in flutter stability may be obtained by rotating the fibers away from the x-axis. For angle-ply plates, inplane normal and shear loads and crossflow have a destabilizing effect on flutter similar to that obtained for orthotropic plates. However, for symmetric plates with the fibers not aligned with the x-axis, the cross-stiffness terms give rise to an improvement of the flutter stability with cross-flow angle. Flutter calculations for equivalent symmetric, angle-ply, and general unsymmetric plates indicate that for no cross-flow and no inplane shear loads, plates with an angle-ply construction will have the highest flutter stability. If cross-flow or inplane shear loads are present, symmetrically constructed plates may have higher flutter stability. Classical plate theory does not consider bending-extensional coupling and cross-stiffness terms, and therefore gives inaccurate and usually nonconservative flutter boundaries for laminated plates. Reduced bending stiffness theory, an approximate flutter theory which accounts for the coupling by reducing the plate bending stiffness as determined by the coupling terms and then neglects the coupling in solving the equations, gives flutter solutions that are adequate for all plates for which numerical results were obtained. / Doctor of Philosophy