Purpose This study was undertaken to identify the lesson topics that are being taught in exploratory agriculture classes in Virginia and compare these lesson topics to lesson topics that should be taught in exploratory agriculture classes as perceived by exploratory agriculture teachers, State Department of Education agricultural education supervisory staff, teacher educators in agriculture, and vocational directors in those school systems offering exploratory agriculture classes. Population The population of this study consisted of 50 teachers of exploratory agriculture, 11 teacher educators, 8 agricultural education supervisors, and 15 vocational directors. Eighty-nine percent, or 75, of the potential respondents marked and returned the opinionnaire in usable form. Procedure Two instruments were developed for purposes of this study; one for teachers of exploratory agriculture classes and one for agricultural education supervisors, agricultural teacher educators and vocational directors. A list of possible lesson topics that might be taught in exploratory agriculture was selected from a review of literature on exploratory agriculture and this list of lesson topics was included on both instruments. The instruments were evaluated by a panel of experts and pilot tested. Respondents were asked to check lesson topics that should be taught in exploratory agriculture classes, and to rate the importance of those lesson topics to an exploratory agriculture class on a 1 - 5 point Likert scale. Teachers were also asked to check lesson topics they are presently teaching and to record the amount of time, in class periods, they spend on each lesson topic. Summary of Findings None of the 49 lesson topics on the opinionnaire were taught by 100 percent of the teachers, and two lesson topics were not taught by any teacher. Additional lesson topics in technical agriculture were added by 52 percent of the teachers. The lesson topic taught by the largest number of teachers (N = 32) was "Understanding the meaning of agriculture and agribusiness," and the largest mean number of class periods (2.72 class periods) was also spent on this topic. Respondents indicated that 39 of the lesson topics on the opinionnaire should be taught in exploratory agriculture classes. The lesson topic ranked the highest on mean importance was "Exploring the occupational opportunities in agriculture" with a mean importance of 4.30. Thirty of the 39 lesson topics that should be taught in exploratory agriculture had frequency counts of 20 percent when compared to frequency counts for lesson topics presently taught by exploratory agriculture teachers. There were significant differences at the .05 level on 12 lesson topics when comparing the respondent groups on this perception of lesson topics that should be taught. On a comparison of the mean importance of lesson topics among the respondent groups, differences large enough to be of importance were found on four of the lesson topics. Major Recommendation The exploratory agriculture curriculum committee should give considerable attention to the findings of this study in the finalization of a state curriculum guide for exploratory agriculture classes. / Ed. D.

A liquid household dye and two fabrics, a cotton drill and a crease resistant cotton muslin, were used to pursue the following objectives: (1) to develop a dyeing procedure for improving the colorfastness of a household dye; (2) to evaluate the effects of temperature, time, and pH (hydrogen ion concentration) of the dyebath on the colorfastness properties of the household dye selected; (3) to evaluate the effects of after treatments of acetic acid and copper sulfate; and (4) to evaluate the dyed samples for colorfastness to light, washing, and crocking. Dye results were evaluated by the use of the Gray Scale for Color Change and the AATCC Chromatic Transference Scale. Colorfastness ratings were statistically analyzed. Major findings of the research included the following: 1. The cotton drill fabric had higher colorfastness ratings for lightfastness, washfastness, and dry crocking than did the crease resistant cotton muslin. For wet crocking, both fabrics had considerable color transference. 2. A dyebath temperature of 210°F produced significantly higher ratings for lightfastness and washfastness in both fabrics tested. 3. The aftertreatment of 1% copper sulfate solution resulted in significantly higher lightfastness ratings for both fabrics tested. 4. There was no significant difference in the dyeing times of 10 minutes and 30 minutes, although the time of 30 minutes produced slightly higher ratings. / Master of Science

A program of <u>in situ</u> and laboratory studies was conducted to elucidate the role of the deposited sediments of the Niagara Reservoir in affecting the quality of the flow of the Roanoke River above the headwaters of Smith Mountain Lake. Agronomic analysis techniques were adapted and applied to provide quantitative analysis capability for the sediments. The superficial sediments were observed to constitute a considerable reservoir of nitrogen and phosphorus, which, during the anoxic bottom conditions occurring during the summer months, caused an enhancement of concentrations in the water column. Conversely, during the winter months, the superficial sediments acted as a phosphorus and nitrogen sink, removing both materials from the water column. Laboratory batch and microcosm studies made it possible to quantify the release and removal of nitrogen and phosphorus under aerobic and anaerobic conditions, and to elucidate the factors upon which the exchanges depended. The phosphorus interactions were found to be governed principally by sediment iron and organic matter content. Under aerobic conditions, phosphorus adsorption could be described by the Langmuir Isotherm. The most important nitrogen release mechanism was found to be a cation exchange phenomenon under reducing conditions. Aithough the effective zone of exchange was found to extend only about 2 mm into the sediment surface, the analysis of cores showed the existing profile to be rich in both phosphorus and nitrogen forms, which could be exposed to the water column with sufficient mixing. The deposited sediments of Niagara Impoundment showed a capacity to redistribute the impoundment influent nutrient load, causing an enhance~ ment of the quantities released during the summer months, thus magnifying the impact on the waters of Smith Mountain Lake. The maintenance of aerobic benthic conditions could, at a tremendous energy cost, prevent the sediment releases from occurring. In the long term, sediment nutrients deposited in the past, without proper control, could provide a continuing source of N and P to the waters of Smith Mountain Lake, thereby reducing the effectiveness of upstream control of point and diffuse sources. / Ph. D.

The structure of cellular arrays and Tessellation Automata are introduced as a "fabric" for use in the implementation of self-testing and self-repairing computational configurations. Testing schemes are suggested for use in the "self-testing" operation of this computer system. Sequentially propagating tests are examined for both finite and infinite geometries of cellular arrays. A static parallel testing procedure is also suggested which offers these advantages: (1) the parallel testing procedure is transparent to the computer configuration, (2) very little computational down-time" results from testing, and (3) the parallel testing procedure does not initiate reconfiguration of the computational configuration. / Master of Science

What happens in institutions like schools or hospitals when local service provision overlaps with the control of national borders? Such overlap is unavoidable if unlawful residents are to be excluded from mainstream public services. With this explicit aim, governments not only modify the rules and established practices of welfare provision, but also encourage the people who administer and deliver these services to incorporate the logic of immigration control into their everyday work. To identify and better understand the concrete mechanisms that either help or hinder such internalisation of immigration control, this study systematically compares three spheres of service provision – healthcare, education and social assistance – across two distinctive legal-political environments: Barcelona/Spain and London/UK. Looking at official policies as well as their implementation, it primarily draws on a total of almost 90 semi-structured interviews with irregular residents, providers and administrators of local services, and representatives of NGOs and local government. Its innovative analytical framework helps to map and explain the significant variation in how immigration control works within different institutions and how individual actors occupying key positions in these can reproduce, contest, or readjust formal structures of inclusion and exclusion. While the way in which national – but also sub-national – governments frame and address irregular migration plays an important role, certain sectors of welfare provision and some categories of ‘street-level-bureaucrats' are generally more likely to internalise immigration control than others. This reflects different degrees of professionalisation and individual discretion, but also attachment to different institutional logics and objectives. Drawing on organisation theory, the study also traces institutional responses to these external demands, which are key to understand the varying degrees of internal resistance. The thesis offers an original and empirically grounded perspective on the consequences and inherent limitations of internalised control and contributes to general debates on the effectiveness of immigration policy.

Halogenated monocyclic and bicyclic heteroaromatic azines, possessing a six or ten w-electron system and one or two ring nitrogens, have been shown to undergo nucleophilic displacement of halide ion with a variety of nucleophiles. A detailed review of the relative reactivity of compounds of these classes, as well as halogenated heteroaromatic azines containing as many as four nitrogen atoms has appeared. / Ph. D.

The two principal objectives of this study were: (i) to estimate and compare net revenue associated with alternative pest management strategies for Virginia soybean producers, and (ii) to compare attractiveness of different pest management options when net revenue risk is considered in conjunction with the corresponding level of expected net revenue. The method used to complete the first objective was to modify 1983 Virginia Cooperative Extension Service soybean budgets to correspond with alternative pest management strategies and then compare the average net revenue of the alternatives. The method used for completing the second objective was to develop a simulation model of net revenue for a representative Virginia soybean farm using alternative pest management strategies. Probability distributions of net revenue were generated and then compared using stochastic dominance analysis. Results from the net revenue comparisons of both expected net revenue and net revenue risk suggest that producers would prefer strategies which incorporate an integrated pest management (IPM) approach to pest control rather than an approach which relies completely on pesticides. Since pesticide usage is associated with negative environmental effects, the IPM alternatives, which in general decrease pesticide usage, would be preferred from the social as well as the private viewpoint. / M.S.