The relationships among body weight, body composition, adipose tissue cellularity and the onset of sexual maturity were studied in Japanese quail (Coturnix coturnix japonica). In an initial experiment, body composition and sexual maturity were examined in response to photoperiodic and hormonal manipulations. Attempts were made to modify body composition, and thereby age at sexual maturity, by feeding diets containing PTU (4-phenyl-2 thiouracil), by imposing a daily photoperiod (IP) of four hours, by the subcutaneous implantation of estrogen to females and testosterone to males, and by the intramuscular injection of turkey growth hormone and anti-sera to turkey growth hormone. The quail were sacrificed at 63 days of age and body composition was examined. Quail subjected to the IP treatment failed to enter sexual maturity by 63 days of age, while about 50% of the controls receiving a photoperiod of 14 hours were sexually mature at this age. The failure of these quail to mature was associated with a reduction in body fat. The effects of the other treatments on sexual maturity, however, were not consistently associated with differences in body weight and/or body composition. In the second phase of this study, adipocyte hyperplasia was examined in relation to sexual maturity. Total DNA concentrations in the stromal and lipocyte fractions of collagenase-digested abdominal fat depots were determined on a chronological age basis from 28 to 240 days of age. In both males and females, significant increases in abdominal fat weights at ages beyond the age at sexual maturity were associated with increased DNA concentrations in abdominal fat adipose tissue. These results suggested that mature Japanese quail were capable of hyperplastic fat deposition. In the final phase of this study, the incorporation of methyl-³H-thymidine into DNA of lipid and non-lipid fractions of collagenase-digested abdominal fat from both ad libitum and restricted-fed (70% of ad libitum intake) quail was examined. Regardless of the feeding regime and stage of maturity, substantial radioactivity was recovered from both the stromal and lipocyte fractions when the quail were examined 24 hours after the administration of tritiated thymidine. When quail were examined five days after the administration of tritiated thymidine, an apparent migration of radioactivity from stromal to lipocyte DNA occurred. It was concluded that this pattern represented mitotic activity of adipocyte progenitor cells located in non-lipid fractions of adipose tissue, and the subsequent maturation of these cells into lipocytes as they accumulated lipid. The hypothesis that adipocyte progenitors reside in both the stromal and lipocyte fraction, however, was not disproven. Nevertheless, the similarity of results obtained prior to, at, and subsequent to the onset of lay indicated that adipocyte hyperplasia contributes to increases in adipose tissue mass in mature Japanese quail. / Ph. D.

McLaughlin et al (1977), Dressel et al (1970, Corson (1975), and others characterized departmental administrators in four-year colleges and universities on a continuum ranging (1) from a"static" administrator, somewhat passively maintaining the status quo , to a"leader-like" individual aggressively pursuing change. In a related (1979) study, Terry encountered the suggestion that the activities and behaviors of administrators in reality may not be one dimensional as described in the literature. Consequently, in this doctoral analysis, Terry formally examined the following possibilities: 1) that the manner in which department heads discharge their major duties and responsibilities may lie in more than one dimension, and 2) that multiple department heads may be dimensional differences among demonstrated operationally in a sample of former state colleges where change may be valued both in institutional programs and in traditional faculty roles of teaching and public service. The study contradicted significant parts of the extant literature describing administrative style. Moreover, the study raised a serious question about the progress made by former state teachers colleges in their transition to comprehensive university status. / Doctor of Education

This study presents some analysis concepts and decision tools for the problems encountered in designing and implementing a flexible manufacturing system. SIM-Q, an input-generator for simulation modelling developed in this study provides a powerful and expedient tool for resolving the material handling system selection, work scheduling, input control, and real time operation problems. The problem of input control is examined using SIM-Q and the viability of operating a flexible manufacturing system as a programmable transfer line is explored. SIM-Q is also used in this study to test the robustness of CAN-Q in modelling an existing FMS. A linear zero-one linear programming model is formulated for the machine mapping and pooling problem. The system synthesis problem is solved by applying CAN-Q in an interactive computer program developed in this study. This model provides an integrated approach to the product selection and machine requirements planning problems. Finally, a dynamic decision approach to the justification of the FMS is developed and presented by imbedding queueing theory with simulation in a decision analysis framework. / Ph. D.

In an introductory physics course, problem solving skills are not traditionally taught. The instructor explains the physical theory and works example problems. Many students, however, are not able to develop the ability to solve problems implicitly. The program of Explicitly Structured Physics Instruction (ESPI) was developed to teach problem solving skills explicitly. It is designed to help students organize their work, increase their accuracy, eliminate initial panic or lack of direction in approaching a problem, increase confidence in problem solving, promote understanding instead of rote memory, and improve the students' ability to communicate with the instructor and other students. It provides not only an explicit strategy for problem solving, but also a structure for examining formulas called the formula fact sheet, and an opportunity for practice and feedback in a problem solving session which involves the use of out loud thinking. The program of ESPI was developed over five academic quarters of testing. A statistical analysis was performed on the data obtained, but the qualitative data obtained from student interviews and questionnaires, as well as the instructor reaction to the program, provided the main source of input in the development of the program and the measurement of its success. Reaction to the program in its final revised form was very positive. Over 90% said that they would use the strategy even if it were not required, and that the formula fact sheet had been very helpful. Over 75% said that the problem solving session was very helpful. Final grades of those who used the strategy were significantly higher than those who did not. Retention of students in the course was raised from 70% to 86%. The study indicates that a well integrated program built around the use of a problem solving strategy can help students focus on understanding physics and the problem sovling process. / Ph. D.

The purpose of this study was to determine why some counselor educators seek specialized accreditation for their programs, and some others do not. The relationship between institutional size, institutional control and faculty publication record and the decision to seek accreditation was also studied. The basic design of this study involved a national survey completed by 122 chairpersons in counselor education programs. This represented a 75.3% response. Both parametric and non-parametric statistical analyses were performed. Ten institutions were selected for site visits and/or follow-up interviews by telephone. The results of the study indicated that many reasons account for voluntary application for specialized accreditation. A high correlation between expectations and achieved outcomes was reported. The interview data indicated that economic and status reasons are the most important motivating factors in seeking accreditation, even more important relating to quality assurance and program improvement. The two most frequent reasons for not seeking accreditation were related to cost and lack of perceived benefits. A correlation was found between institutional size, control, and faculty publication record and the decision to seek accreditation. Large graduate schools tended to be recognized by more than one accrediting agency. Small graduate schools tended not to have recognition by any specialized agency. A majority of private institutions did not have any specialized accreditation. Institutions without specialized accreditation or those accredited by NCATE reported fewer faculty publications than those institutions recognized by two or more agencies. There was strong agreement by respondents that the self-study and accreditation review helps to sustain or enhance program quality. / Ed. D.

By the addition of selected impurities to silicon it is possible to affect its physical, optical and electrical properties to a remarkable extent. Of great technological importance are the elements of groups III and V which introduce shallow acceptor and donor levels and control the equilibrium charge density. These levels have been studied extensively and are well understood. However, other impurities and structural defects are known to introduce deep levels. These levels may act as acceptors or donors in the traditional sense but they can also control the recombination of non-equilibrium charge carriers. The properties of these recombination levels reflect the processes of energy exchange and provide information on the defect structure and energy spectrum and are thus of physical interest. Also since they control the excess carrier lifetime which is a critical parameter in many semiconductor devices they are of interest to the technologist. The major difficulty in analyzing these levels arises from the catalytic nature of the recombination centers which allows an extremely low density of centers to significantly affect the recombination lifetime. Most bulk single crystal silicon techniques applied to date use activation processes with high resistivity, high recombination center density samples. This severely limits the range and sensitivity of analysis. In this dissertation is detailed a new approach to more accurately determine lifetime parameters in conjunction with a phenomenological model which describes the recombination using a set of characterizing parameters. The technique is used to characterize the levels responsible for recombination in single crystal silicon after controlled heat treatments and, also, in gamma irradiated and impurity containing silicon. / Ph. D.

Lactation records of cows born since 1964 were used to compute Cow Indexes (CI) for 581,519 Holsteins and 352,758 Jerseys. CI were used to predict Modified Contemporary Deviations (MCD) of daughters at three levels each of herd mean (µ) and standard deviation (σ), and regressions were compared to expected values. For Holsteins, regressions were greater than expected in herds with average µ or high σ, suggesting that heritability (h²) should be higher for cows in those herds. Heritability estimates agreed with observed regressions for herd σ (h2 of .178, .193, and . 206 as herd σ increased) but not for herd µ (h² of . 222, .163, and .206). For Jerseys, regression results indicated that h² should increase with herd µ, but there was no trend for herd σ. Heritability estimates agreed with the observed regressions for µ (h² of .246, .291, and .331) but not for σ, as h² increased substantially ( .254, .293, and .371) as herd σ increased. Eight adjustments were made for CI: two varied h² to adjust for genetic effects, two adjusted MCD for environmental effects, and four were combinations of these. For Holsteins, regressions of daughter MCD on darn CI were greater than expected for all CI, but regressions of son MCD on darn CI were less than expected. Rankings of CI, based on R² , differed considerably for the three groups examined (all daughters, daughters of elite cows, and sons). For Jerseys, CI of elite darns predicted offspring MCD as expected, but for several CI, regressions for all daughters were less than expected. There were smaller differences in rankings of CI than for Holsteins. Under the assumption that large true breed differences are unlikely, the best CI for both breeds had MCD standardized to a common variance, with h² of .20. This was nearly optimal for Jersey groups, although less than optimal for Holsteins. This CI adjusted for environmental effects of herd a, ignoring differences in genetic variation. It decreased differences among CI for cows in high variance herds, and increased differences in low variance herds. / Ph. D.

In order to extract a drainage network from a LANDSAT scene of mountainous terrain, it is necessary to use an illumination model to separate the reflectance information from the topographic information in the LANDSAT data. From the reflectance information, visible stream segments can be detected. From the topographic information, ridges and valleys can be located and assigned relative elevations by an elevation growing model. Based on these, a complete elevation model can be estimated by interpolating between ridges and valleys and this estimate can be improved by making it consistent with the topographic information. Also the LANDSAT imagery can be reconstructed to evaluate the illumination model. In order to label flow directions of visible stream segments, constraints at junctions based on orientations and lengths are defined and a consistent labeling technique is used. / Ph. D.

Two studies were conducted to determine the visual elements that influence visual compatibility between natural and built environments. In the first study subjects (N=109) rated one of three versions of color slides of 20 western United States landscape scenes on how much they consisted of 11 simple visual elements (Round, Square, Conical, Cylindrical, Vertical, Horizontal, Diagonal, Curvey, Smooth, Rough, and Relative Size). The first version was a Pre-impact scene without human-made structures. The second version was a Post-impact version of the same scene but with a structure on it. The third version was a Structure-alone version, consisting of only the structure. Subjects rated either the Pre-impact or the Structure-alone scenes on the 11 design element dimensions. For each scene the absolute value of the difference between the mean pre-impact rating and the mean structure rating on each dimension were the measures of compatibility between the structures and their environments to be used as predictors in subsequent regression analyses. Independent groups of subjects rated the Pre-impact scenes on scenic beauty, while others rated the post-impact scenes on scenic beauty, overall compatibility, and severity of impact (of the structure). These mean values for each scene provided the criteria values for the regression analyses. In general, the results showed that the compatibility measures of Rough texture and Relative Size were strong predictors of the criteria. Diagonal and Conical element compatibility were less pervasive but significant predictors, as well. The second study (N=l36) was similar to the first but used 45 simple line drawings of and Square and landscapes. Vertical In this study Relative element compatibility Size, were significant predictors of the criteria, but accounted for less variance than the study one models. Some predictors (e.g., Square elements) predicted in opposite directions across the two studies. / Doctor of Philosophy

A nonlinear three-dimensional vortex-lattice method which treats the steady separated flow over prolate bodies with open separation moving through an inviscid incompressible fluid is developed. The strength and position of the body wake are found as part of the solution. Specifically, flows with smooth-surface separation are considered as opposed to flows with sharp-edge separation treated· with the vortex-lattice concept in the past. To demonstrate the technique, results for the flow over an inclinded ogive-cylinder are presented. In the case of attached flow, comparsions are presented of the results from the vortex-lattice method using optimal and average control point locations with the results of the source-distribution method and with experimental data. Significantly, the same panel arrangement is used in the calculations for both methods. The results demonstrate that the results of the present method is somewhat more sensitive to panel arrangement than are those of the source-distribution method. Also, the effect of control point location varies dramatically as the incidence of the body is changed. In the case of separated flow, comparsions of the results of the vortex-lattice method are made with experimental data and with the results of a typical two-dimensional analogy. The results demonstrate that the present method agrees most favorably with the experimental data windward of a separation line. / Doctor of Philosophy