A short-term selection experiment was conducted with ICR albino mice produced by the reciprocal crossing of two lines of unselected animals which had been random-bred for 28 generations. Lines were developed by selecting for maximum and minimum serum cholesterol (SC) (lines CH and CL), voluntary physical activity (lines AH and AL), 56-day body weight (lines WH and WL) and feed intake (lines IH and IL). An unselected, random-bred control line was maintained with each pair of divergent selected lines (CC, AC, NC and IC, respectively). In the lines selected for SC, physical activity and 56-day body weight, selection was based on individual performance. Twenty-five paired matings plus five extra paired matings were used to perpetuate the lines each generation for five generations. The feed intake lines were perpetuated by within-sex, full-sib family selection with 30 paired matings per generation for five generations. / Ph. D.

The purpose of this study was to determine if a ten week (30 hour) systematic behavior modification program for classroom teachers had an effect on the verbal interaction of these classroom teachers. A second part of this study sought to determine if this verbal change had an effect on the se1f-concept of the teachers' students. A , graduate level, 3 credit hour course was offered to Pulaski County, Virginia classroom teachers, and was based on the Robert Carkhuff model of communications. Ten teachers chosen at random from the class of 40 were selected for the experimental teachers. Ten teachers within the county not enrolled in the class were chosen at random for the control teachers. Ten students were also chosen at random (five boys and five girls) from each of these experimental and control teachers. The instruments used to collect the data were the Flanders Interaction Analysis System for the teachers; and the Piers-Harris Self-Concept Scale, "How I Feel About Myself," was administered to the experimental and control teachers' students. / Ed. D.

The Cocco idea or scale insects are among the most important pests of sylvicultural, ornamental, agricultural and greenhouse plantings throughout the world. There are 21 families comprising 6,000 species. Direct injury occurs from the withdrawal of sap while feeding and from the production of galls. Some scale insects are host specific while others are polyphagous. They feed on many different parts of plants including the roots, trunk, stems, leaves, buds and fruit. / Ph. D.

Fifteen children (mean age 10 years) who were defined as learning disabled (LD) by school authorities and were enrolled in special LD classrooms were matched with 15 children from regular school classrooms on the basis of sex, chronological age, and mental age. Each child performed individually in a two-hour reaction time (RT) session, during which four different RT tasks were administered. All children received the following tasks, ordered as listed: Simple RT (100 trials), Selective RT (100 trials), Choice RT (100 trials), and Search RT (100 trials with one digit in the memory set, 100 trials with memory-set size of 3, and 100 trials of memory-set size of 5). For Simple RT, subjects pulled a reaction trigger with their dominant hand following the symbol []; for Selective RT, the symbol [ or ] was presented and subjects pulled the dominant-hand trigger to [; and for Choice RT, subjects pulled the dominant-hand trigger to [_] and the nondominant-hand trigger to I-I. Prior to each block of 100 trials during the Search RT task certain digits were defined as critical memory-set items (i.e., 1 for Set-Size 1; 0, 2 and 5 for Set-Size 3; and 1, 3, 6, 8 and 9 for Set-Size 5); and the child was requested to pull the dominant-hand trigger if the stimulus presentation was included in the memory set and to pull the nondominant-hand trigger for stimuli not included in the memory set. For each task the stimulus presentation was preceded by a "ready" buzzer and then a random interval ranging from .5 to 1.5 sec. The RTs were equivalent between groups for the Simple RT task, but were significantly slower for the LD children during the Selective, Choice, and Search RT tasks. The between-group, RT difference was maximum for the Selective RT task, and therefore an application of Donders' Subtractive Model reflected that stimulus encoding was the only cognitive dysfunction among the LD children. Furthermore, the functions relating Search RT to Memory-Set Size demonstrated equivalent memory search rates for the normal and LD children. Such findings suggest that RT may be used to diagnose particular cognitive deficiencies or to demonstrate particular facilitative effects of cognitive-remediation programs. The finding that consecutive blocks of 25 trials did not interact with the latencies in any RT task, suggests that individual sessions to obtain diagnostic RT can be as short as 15 minutes (i.e., 25 trials per RT task). The present RT results are discussed with reference to other RT studies that compared reaction latencies between normal and abnormal subjects. / Ed. D.

The feasibility of ensiling swine waste (primarily feces) with ground orchardgrass hay or with ground corn grain was determined by mixing and ensiling the following proportions of each (as is basis): 80:20, 70;30, 60:40, 50:50, 40:60, 30:70 and 20:80. In the swine waste-orchardgrass hay trials, good fermentation occurred in the 40:60 through 60:40 mixtures as determined primarily by pH and lactic acid. Bacteria and total coliform numbers decreased and fecal coliforms were completely destroyed. In a sheep metabolism trial, organic matter digestibility was similar in 40:60 and 60:40 swine waste~orchardgrass hay silages and in orchardgrass hay fed alone, but was higher (P<.05) in an orchardgrass hay plus soybean meal diet. Crude protein digestibility was higher (P<.05) in the orchardgrass hay plus soybean meal diet than any of the other diets. Nitrogen retention was negative (P<.05) for sheep fed the silages. Organic matter digestibility of the swine waste calculated by difference was over 60 percent, In the sheep palatability trial, dry matter intake was similar between the diets. Ina swine palatability trial, dry matter intake decreased as swine waste-orchardgrass hay silages were substituted for the basal diet at levels of 25 and 50% of the dry matter. In the swine waste-ground corn trials, mixtures containing more than 30% waste exhibited good fermentation characteristics. Ensiling reduced the total bacteria numbers and completely destroyed all coliform bacteria. In a sheep metabolism trial, digestibility of dry matter, crude protein, organic matter, and NFE increased linearly CP<.01) as 20 and 40% of the 40:60 and 60:40 silages were substituted for a basal diet composed of 50% of a 14% protein corn-soybean meal mixture and 50% mixed hay. Nitrogen retention (percent of absorbed) decreased linearly for diets containing the 60:40 silage (P<.05). In the sheep palatability trial dry matter intake was greatest (P<.01) for the basal with either 20% of the 60:40 silage or 40% of the 40:60 silage. In the swine metabolism trial, digestibility of dry matter, organic matter, and crude protein decreased as 25 and 50% of the 40:60 and 60:40 swine waste-ground corn silages were substituted for a basal 14% crude protein corn-soybean meal diet. Fecal nitrogen excretion was higher (P<.01) and nitrogen retention lower in swine fed diets containing the silages. In the swine palatability trial, dry matter intake was not different between diets. Swine waste was successfully ensiled with either orchardgrass hay or ground corn grain. Ensiling was an effective way to destroy many potential pathogens. Diets containing these silages were fed to both ruminants and nonruminants. The high levels of fiber in the swine waste-orchardgrass hay silages had an adverse effect on acceptability by nonruminants, but not ruminants. Ruminants and nonruminants both consumed adequate amounts of the swine wasteground corn silages for maintenance. / Ph. D.

The purpose of this study was to investigate the effect of selected socio-demographic variables and attitudinal variables on membership vs. non-membership in the FFA. The groups under investigation were 602 black tenth grade vocational students from 66 high schools in five former NFA states. Criteria for selection of high schools were: (a) must have a high school vocational agriculture program; and (b) must have at least 10 per cent black enrollment in vocational agriculture. Data collected from the sample groups were primarily analyzed using chi-square tests between members and non-members. Pearson Product-Moment Correlation (r) coefficient was used to determine the relationship between percentage black FFA membership and percentage black vocational agriculture enrollment. Responses between FFA members and non-members differed significantly in nine of the sixteen variables. FFA members are more likely to attend rural schools, be children of farmers, live in areas of less than 2,500 population, believe that anyone can be successful in FFA, and respect farmers and farming than vocational agriculture students who are not FFA members. No significant difference between members and non-members could be found on the following variables: the name of the organization, the attitudes toward agriculture, race of student and his/her advisor and reasons for enrolling in vocational agriculture. Fifty-two percent of the students sampled were FFA members. A significant relationship was found between percentage black vocational agriculture enrollment and percentage black FFA membership. / Ed. D.

The central problem in this investigation was to explore antecedent factors associated with role conflict and role ambiguity in the office of the school superintendent. A review of the literature and related studies indicated a paucity of research which related the concepts of (a) personality and (b) organizational variables to the level of (a) role conflict and (b) role ambiguity in the office of the school superintendency. The design treated the personality and organizational variables as independent and the role conflict and role ambiguity variables as dependent. There were 8 personality variables and 15 organizational variables (a) 6 for organizational innovation, (b) 2 for administrative autonomy, (c) 1 for the position, (d) 3 for contextual factors, and (e) 3 for job satisfaction. The 25 variables were translated into operational definitions, and scales were constructed for each of them. Personality was operationalized by the Gordon Personal Profile, and Inventory. These were then used in a correlational analysis to explain the personality and organizational dimensions found. The study used a self-rating questionnaire methodology. The sample population, selected through a systematic sampling procedure, consisted of 366 school superintendents from the Southeastern Region of the United States. There was 296 usable returns on the questionnaire designed for the study. This represented an 80.87% response rate. The Gordon Personal Profile, and Inventory had 279 responses completed according to the directions. The data indicated the following: 1. There was no relationship between (a) role conflict or (b) role ambiguity and the personality variables. 2. There was no relationship between (a) role conflict or (b) role ambiguity and the organizational innovation variables. 3. There was a moderate, positive relationship between role conflict and the administrative autonomy variable of the question that the school system is under too much pressure from outside sources to determine its own course of action. 4. There was a weak, inverse relationship between role conflict and the administrative autonomy variable of the question that the school system is able to determine its own course of action. 5. There was no relationship between role ambiguity and the administrative autonomy variables. 6.There was no relationship between (a) role conflict or (b) role ambiguity and the position variable. 7. There was no relationship between (a) role conflict or {b) role ambiguity and the contextual factors. 8. There was a weak, positive relationship between role conflict and the job satisfaction variable of the likelihood of leaving their positions. 9. There was a weak, inverse relationship between role conflict and the job satisfaction variable of satisfaction with their present positions. 10. There was no relationship between role conflict and the job satisfaction variable of years in office. 11. There was no relationship between role ambiguity and the job satisfaction variables. The administrative autonomy variable of the school system is under too much pressure from outside sources to determine its own course of action accounted for the largest proportion of variance in role conflict. The highest proportion of variance in role ambiguity was accounted for by the administrative autonomy variable of the school system is able to determine its own course of action. Role conflict and role ambiguity in all cases were more directly related to organizational variables than to personality variables. However, the organizational variables did not explain as large an amount of variance in role ambiguity as they did in role conflict. The relationships between (a) role conflict and personality variables, (b) role ambiguity and personality variables, (c) role conflict and organizational variables, and (d} role ambiguity and organizational variables were not affected by partialling out individually the job satisfaction variables. / Ed. D.

The problem addressed by this study was that of determining whether significant differences existed among selected apprehensions of black and white teachers in twelve Illinois School Districts with operative staff desegregation programs. The major assumption of this study was that both black and white teachers have apprehensions related to teaching in schools which have student and staff populations predominately of the opposite race. Three hypotheses were formulated in order to investigate the problem. Data were collected via a questionnaire which was administered to 2,250 teachers. The selected apprehensions were tabulated, and the scores were tested utilizing the chi-square test for independence. The probabilities for the events were reported at the 0.01 level. The findings indicated that both black and white teachers were apprehensive about teaching in schools with populations predominately of the opposite race. The data further revealed that there were no statistically significant differences in the choice of descriptive words used by black and white respondents to identify individuals of the opposite racial groups that they would be most willing to associate with. Further analysis of the data suggests that blacks as a group were more apprehensive about their relationships in the school setting with members of the opposite racial group. / Ed. D.

Sarason has demonstrated that a model who discloses anxiety about performing on tests and at the same time outlines successful tactics for coping with this anxiety has a facilitative effect on the learning performance of high test anxious subjects. The effectiveness of the above model was determined with high test anxious female subjects who were psychologically stressed at the time that they observed the model. Using the number of correct responses per trial and the number of trials to criterion in a serial list learning task as a dependent measure. A 2 (stress - high and low) x 3 (model instruction order) x 16 (trials) analysis of variance failed to demonstrate the effectiveness of the videotape model on the learning performance regardless of whether the model was observed under conditions of stress, or prior to the stress manipulation. Assessment of the stress manipulation using groups who performed without the opportunity to observe a model indicated that the combination of ego-involving instructions plus later negative feedback to the subject about her performance midway through the task was effective, in that performance of high stress subjects later in the study was inferior to low stress subjects. Partial support was seen for earlier studies which indicated that evaluative instructions negatively affected high test anxious subjects. Some methodological differences between Sarason's 1975 study and the present study were discussed as possible sources of explanations of the differential results between the two studies. Future affects of research regarding the examination of the components of the stress manipulation, the use of live versus videotaped models, etc. were outlined. / Ph. D.

Most cattlemen in the Southeast are in the cow-calf business and sell calves at weaning. The extra cost of shipping feeder calves for finishing and then shipping the carcasses back to the East adds to the price of meat. This practice also takes away a potential source of profit by farmers who could finish these calves. Economically, it is difficult for states in the East to compete with grain producing states for the production of slaughter cattle in the feedlot. The alternative of using forages native to the areas of the Appalachians with a minimum of high energy grains should increase the economic potential for producing market animals in this area. / Ph. D.