Thesis (Ph. D.)--Georgia State University, 2006. / Karen M. Zabrucky, committee chair; Laura D. Fredrick, John H. Neel, Dennis N. Thompson, committee members. Electronic text (142 p.) : digital, PDF file. Description based on contents viewed July 16, 2007. Includes bibliographical references (p. 129-135).

Thesis (Th. M.)--Westminster Theological Seminary, 2006. / Vita. Includes bibliographical references (leaves 110-120).

Thesis (Ph. D.)--West Virginia University, 1998. / Title from document title page. Document formatted into pages; contains ix, 122 p. : ill. Includes abstract. Includes bibliographical references (p. 112-117).

Thesis (Honors)--College of William and Mary, 2009. / Includes bibliographical references (leaves 22-25). Also available via the World Wide Web.

PP14 has been shown to suppress the incorporation of [3]H-Thymidine into both mitogenically and allogeneically stimulated lymphocytes in a dose dependent manner. The suppressive activity was shown to be specific, in that PP14 did not affect cellular viability, nor interact with the mitogen phytohaemagglutinin (PHA). Flow cytometric analysis indicated that PP14 had no effect on the expression of the Tac antigen, the transferrin receptor or HLA-DR molecules on the surface of stimulated lymphocytes. Neither did PP14 affect the interaction of interleukin-2 (IL-2) with its cell surface receptor. The suppressive activity was partially reversed by the addition of exogenous IL-2. PP14 inhibited the production of IL-2 from mitogenically stimulated lymphocytes and led to a small, but significant reduction in soluble IL-2 receptor release. Radiolabel binding studies and IL-2 dose response curves indicated that PP14 affected the affinity of the IL-2 receptor on PHA stimulated lymphocytes. This was supported by the observation that PP14 increased the level of cell surface-associated IL-2 on stimulated lymphocytes. There was a small inhibition of gamma interferon levels early in the culture period. PP14 had no effect on the CD4/CD8 ratio following stimulation and was not found to be associated with the cell surface, nor mask cell surface expression of the CD2 antigen. These data suggest that the immunosuppressive activity of PP14 may, in part, be mediated via a modulation of the functional, high affinity IL-2 receptor. It is not known as yet whether such an activity is effective at the level of induction of the receptors or whether the primary control is at another level of the response. PP14 may have implications in the study of implantation and fertility and prove of wider interest in the field of transplantation biology and the control of the immune response.

The explanation of the emergence of untaught behaviour has been a topic of considerable interest in behaviour analysis. The experiments in this thesis were designed to examine some of the processes underlying these emergent relations. In doing this, two different paradigms were examined - stimulus equivalence and transitive inference. The experiments leading to a formal definition of equivalence relations are reported, and the demonstration of cognitive abilities with both humans and non-humans described. The explanations proposed for the basis of stimulus equivalence are discussed. Data from five experiments are then presented. Experiment 1 considered the role of naming in stimulus equivalence and Experiment 2 contrasted this performance with the establishment of transitive inference, both experiments being carried out with adults with learning disabilities as subjects. The results from these experiments suggested that while naming behaviour may help to establish emergent relations, it may not be the basis of stimulus equivalence, and that it may be possible to account for performance on both stimulus equivalence and transitive inference tests in terms of reinforcement contingencies. While subjects who display stimulus equivalence are likely to also display transitive inferences, the reverse relation may not be true. Experiments 3 and 4 examined the effects of a disruption of the baseline relations on performance on transitive inference and stimulus equivalence tasks. These experiments were both carried out with normally able adults, adults with learning disabilities, and normally developing young children. Experiment 5 was a replication of Experiment 4 with a tighter methodology and a larger number of subjects with learning disabilities. It is suggested that the results obtained in Experiments 4 and 5 can be explained by the development of contextual control of the equivalence relations. The results from these experiments suggested that the transitive inference and stimulus equivalence paradigms may respectively be concrete and abstract examples of more general emergent relations. These paradigms may also prove to be very useful teaching tools for helping to establish emergent relations.

The present study used a Microsoft Visual Basic computer program to examine the effects of changing reinforcement schedule components on response allocation following previously extinguished responding. In Experiment 1, participants allocated responses to three different colored buttons that moved around the screen after each successive click. Components were arranged such that clicking on one button resulted in reinforcer delivery on a programmed variable-interval (VI) 10 s schedule while clicking either of the other two buttons did not result in programmed reinforcer deliveries. Results of Experiment 1 may have been confounded by an unintended signaling of component changes, so an identical experiment was repeated without a point counter visible to the participants. The results of Experiment 2 indicated an induced responding on the button most recently associated with reinforcement when the reinforcement schedule changed. This induction effect is discussed in relation to current conceptions of relapse effects in the scientific literature and implications for treatment of challenging behavior.

This study evaluated the effects differential reinforcement of alternative behavior on response persistence. A total of four participants from a local 2nd grade classroom participated in this study. A two component multiple schedule that included baseline (i.e., reinforcement of a target response) and DRA (i.e., reinforcement of an alternative response and reinforcement of the target response) conditions was conducted. Attempts were made to keep rates of reinforcement as similar as possible across components. Extinction was then implemented in the context associated with each component, and response persistence was measured. Results indicated three distinct patterns of responding: 1) alternative behavior was never emitted during the DRA component (two participants), 2) only the alternative behavior was emitted during the DRA component (one participant), and 3) both the target and the alternative behaviors were emitted during the DRA component (one participant). Overall, the results of this study indicated that DRA could result in inadvertent strengthening of target behavior. However, that strengthening may be mitigated if reinforcer rates are similar.

Few researchers have compared preference for reinforcement and response cost within a token economy, and the results have shown that preference varies among individuals (e.g., Donaldson et al., 2014; Iwata & Bailey, 1974; Jowett Hirst et al., 2016). Preference for response cost is an interesting phenomenon because response cost is a punishment procedure and is often considered aversive. Therefore, identifying the variables that influence preference for response cost is an important area of research. Some authors have suggested that the immediate delivery or presence of tokens might influence preference for response cost, but these variables have yet to be experimentally evaluated. The current study evaluated whether the presence of tokens influences selection of response cost over reinforcement in three typically developing preschool children by systematically varying the presence of tokens across both the reinforcement and response cost procedures. Results suggest that the presence of tokens influenced selection for one out of three participants. Implications of the results are discussed in terms of clinical application and directions for future research.

An attempt to minimize interference drag in a wing-fuselage junction by means of inserting a fillet is presented in this thesis. The case of a low-wing com- mercial transport aicraft at cruise conditions is examined. Due to the highly three dimensional behaviour of the flow field around the junction, a thin-layer Navier-Stokes code was implemented to estimate the drag forces at the junc- tion. Carefully selected design variable combinations based on-the theory of Design of Experiments constituted the initial group of feasible cases for which the flow solver had to be run. The drag values of these feasible cases were then used to create a second order response surface which could predict with rea- sonable accuracy the interference drag given the value of the design variables within the feasible region. A further optimization isolated the minimum in- terference drag combination of design variable values within the design space. The minimurn interference drag combination of design variable values was eval- uated numerically by the flow solver. The prediction of the response surface and the numerical value obtained by the flow solver for the interference drag of the optimal wing-fuselage combination differed by less than five percent. To demonstrate the ability of the method to be used in an interdisciplinary analysis and optimization program, a landing gear design module is included which provides volume constraints on the fillet geometry during the fillet sur- face definition phase. The Navier Stokes flow analyses were performed on the Cranfield Cray su- percomputer. Each analysis required between eight to twelve CPU hours, and the total CPU time required for the optimization of the six variable model described in the thesis required thirty Navier Stokes runs implementing the Design of Experimens and Surface Response Methodology implementation. For comparison, a typical optimization implementing a classical conjugate di- rections optimizer with no derivative information available would probably require more than forty iterations. Both the optimization and the flow solver results are discussed and some recommendations for improving the efficiency of the code and for further ap- plications of the method are given.