Protein Kinase C (PKC) represents an important regulatory element in the signal transduction pathways of mammalian cells. Research interest has increased enormously since the discovery that PKC plays critical roles in cell differentiation, tumor promotion, oncogenesis and cell regulatory processes. The primary driving force of this project was the study and development of enantioselective PKC inhibitors. To accomplish this objective the four stereoisomers, (2S/4S)-, (2RI4S)-, (2R14R)-, and (2S/4R)-6-N,N-dimethyl-2-methyl-2-oxo-l,3-dioxa- 4-pentadecyl-6-aza-2-phosphacyclooctane bromides (la-d) were synthesized and evaluated. Long-alkyl chain optically pure epoxides, the key intermediates for the synthesis, were prepared from relatively inexpensive glyceraldehyde surrogates. Several other intermediates exhibited other biological responses including spermicidal, anti-HIV, mycobactericidal, and anti-cancer activities. / Ph. D.

Clostridium difficile is a major nosocomial pathogen responsible for causing pseudomembranous colitis. It is estimated that 25% of antibiotic-associated diarrhea is due to C. difficile. These diseases result from intestinal tissue damage caused by two of the largest known bacterial toxins, A and B. Molecular studies of the C. difficile toxins have identified a 19.6 kb toxigenic element that contains both toxin genes flanked by three small open reading frames (ORFs). The focus of this study is to elucidate the function of the ORF, designated txeR, which is located at the beginning of the toxigenic element. The deduced amino acid sequence of txeR predicts a 22-kDa protein that contains a helix-turn-helix motif characteristic of DNA binding regulatory proteins. To determine if the protein TxeR regulates expression from the toxA, toxB, and txeR promoters, gene fusions were constructed that contained the various promoter regions and a reporter gene. The immunodominant region of toxin A located at the carboxy-terminus, termed the repeating units (ARU), was selected as the reporter gene. Expression studies were performed in Escherichia coli host strains. Levels of ARU expression were measured by enzyme-linked immunosorbent assay using an ARU-specific monoclonal antibody. Expression levels of ARU from the toxin B promoter region with TxeR supplied on the same plasmid (in cis) or on a different plasmid (in trans) were determined. In cis, ARU levels were 50-fold higher than strains without txeR. In trans, expression of ARU from the toxin B promoter region increased over 800-fold. When TxeR was supplied in trans to a toxin A promoter region-ARU fusion, expression levels of ARU increased over 500-fold. To test for autoregulation, TxeR was supplied in trans to the txeR promoter region fused to ARU. The effect was an increase of ARU expression up to 20-fold over background. These results suggest that TxeR is a trans-acting regulator that stimulates expression of the C. difficile toxins and is subjected to autoregulation. / Master of Science

Quantitative resistance is controlled by multiple genes and has been shown to be a durable form of resistance to pathogens affecting cultivated crops including soybeans (Glycine max L. Merr). Root rot of soybean caused by Phytophthora sojae ranks among the most damaging soybean diseases. Quantitative resistance has proven durable in soybean against P. sojae, however the molecular mechanisms underlying this form of resistance are still unknown. The objective of this project is to gain insight into molecular basis of quantitative resistance in the soybean-P. sojae pathosystem. The approach was to use global transcriptional profiling based on microarray technology to identify genes that were differentially expressed in four cultivars of soybeans with varying levels of quantitative resistance at different time points during infection by P. sojae. Our results provide a better understanding of the potential regulatory factors that may contribute to quantitative resistance during early hours of P. sojae infection. / Ph. D.

Many observers feel that the Staggers Rail Act of 1980 is responsible for a "renaissance" in the U.S. freight railroad industry. Prior to the passage of the Staggers Act, railroads had to petition for government approval for nearly every business decision. The ability of the railroad industry to enter and exit certain lines of business was strictly controlled, as was the ability of the industry to rationalize their physical plant. The Staggers Act removed most, but not all, of these regulatory restrictions. But this is the popular perception correct? By using a F test to compare a series of regressions, this thesis argues that Staggers did produce a structural change in the industry. Moreover, this thesis asserts that the changes noted in the results are consistent with the view that deregulation has been a success - that the industry is more efficient and that the benefits of deregulation have been shared between the railroads and the public. / Master of Arts

Stochastic modeling to represent intrinsic and extrinsic noise is an important challenge in molecular systems biology. There are numerous ways to model intrinsic noise. One framework for intrinsic noise in gene regulatory networks was recently proposed within the discrete setting. In contrast, extrinsic perturbations were rarely modeled due to the complex mechanisms that contribute to its emergence. Here a discrete framework to model extrinsic noise is proposed. The interacting species of the model are represented by discrete variables and are perturbed to represent extrinsic noise. In particular, they are subject to a discretized lognormal distribution. Additionally, a delay is imposed on the update with a certain probability. These two perturbations represent global extrinsic noise and pathway-specic extrinsic noise. It leads to large variations in the concentration of proteins, which is consistent with an existing continuous way of modeling extrinsic fluctuations. The framework is applied to three different published discrete models: the cell fate of lambda phage infection of bacteria, the lactose utilization system in E. coli, and a signaling network in melanoma cells. The framework captures factors that signicantly contribute to the random decision between lysis and lysogeny as well as explains the bistable switch in the model of the lac operon. Finally, a feed-forward loop analysis is conducted by measuring and comparing the noise level in the target protein of feed-forward loops. This analysis reveals the ability of certain feed-forward loops to attenuate or amplify fluctuations, dependent upon various levels of noise. In conclusion, this thesis aims to resolve the question of how the extrinsic noise can be modeled and how biological systems are able to maintain functionality in the wake of such large variations. / Master of Science

This study sought to better understand the impact of feedback on performance by examining how regulatory focus and message framing potentially interact to influence recipient's attitudes towards and recall of performance feedback recommendations. Participants were 221 undergraduates. Participant's chronic regulatory focus orientation was measured in phase 1. In phase 2, regulatory focus orientation was manipulated prior having participants complete a puzzle task. After completing the task, they were given performance feedback recommendations that were framed to highlight either promotion or prevention concerns. Their attitudes towards and recall of the recommendations they received were then measured. Though not all of the predictions of the study were supported, results indicated a significant three-way interaction between chronic promotion, the manipulation of regulatory focus, and the framing of the performance feedback recommendations that qualified the relationship between chronic promotion and attitudes. This finding supports the notion that a better understanding of how feedback impacts subsequent performance is possible by studying the interaction between regulatory focus and message framing. Implications and recommendations for future research are discussed. / Master of Science

During the past decade, many successful deterministic models of macromolecular regulatory networks have been built. Deterministic simulations of these models can show only average dynamics of the systems. However, stochastic simulations of macromolecular regulatory models can account for behaviors that are introduced by the noisy nature of the systems but not revealed by deterministic simulations. Thus, converting an existing model of value from the most common deterministic formulation to one suitable for stochastic simulation enables further investigation of the regulatory network. Although many different stochastic models can be developed and evolved from deterministic models, a direct conversion is the first step in practice. This conversion process is tedious and error-prone, especially for complex models. Thus, we seek to automate as much of the conversion process as possible. However, deterministic models often omit key information necessary for a stochastic formulation. Specifically, values in the model have to be scaled before a complete conversion, and the scaling factors are typically not given in the deterministic model. Several functionalities helping model scaling and converting are introduced and implemented in the JigCell modeling environment. Our tool makes it easier for the modeler to include complete details as well as to convert the model. Stochastic simulations are known for being computationally intensive, and thus require high performance computing facilities to be practical. With parallel computation on Virginia Tech's System X supercomputer, we are able to obtain the first stochastic simulation results for realistic cell cycle models. Stochastic simulation results for several mutants, which are thought to be biologically significant, are presented. Successful deployment of the enhanced modeling environment demonstrates the power of our techniques. / Master of Science

This study examines the trading activity of a large cross section of American bank holding companies upon various sub-events associated with the introduction of Basel III. An event study methodology was applied to various sub-composite portfolios, as determined by regulatory capitalization and leverage ratios. The results suggest that statically significant abnormal negative returns occurred on the announcement to negotiate due to heightened regulatory uncertainty, especially amongst the least capitalized and highest leveraged banks. However, this effect is complemented by statically significant positive returns upon the release of the initial guidelines. Reactions to subsequent events report to be less significant.

This thesis contributes to the research literature by reporting the results of an investigation that explores whether regulatory governance practices in Nigeria’s downstream petroleum sector are fit for purpose. The rationale for the study originated from issues relating to the management of Nigeria’s downstream petroleum sector that were identified in the extant literature. These issues were of such significance that their resolution could impact positively and materially on Nigeria’s economy and at the same time the research would fill a gap in the relevant literature. The data for this empirical research were collected using questionnaire and interview instruments and the findings were analysed against a backdrop of the Public Interest Theory of Regulation. The results obtained revealed perceptions of major weaknesses in the regulatory governance practices adopted by Nigeria’s downstream regulatory agencies namely: the regulatory independence of Nigeria’s downstream regulators has declined over time; there are flaws in the accountability practices of Nigeria’s downstream regulators; and there are other related factors such as the absence of openness, poor consultation and a lack of public sensitisation that affect the transparency practices of Nigeria’s downstream regulators. Interestingly, the results also revealed that although Nigeria’s downstream regulators appear to possess the required skills to regulate the sector, their talents are not being fully utilised. Recommendations to resolve the weaknesses identified are made which, if properly and effectively implemented, should have a significant positive impact on the Nigerian economy. Such recommendations may also be applicable to those countries with similar regulatory governance challenges.

As primeiras agências reguladoras foram criadas a partir da segunda metade dos anos 1990, e a mais recente delas, em 2005. Com as agências surgiram também os atores privados regulados, os usuários e consumidores, e uma nova forma de interação entre os Poderes Executivo, Legislativo e Judiciário. Esses atores participam e dão forma ao processo de aprendizagem institucional das agências. Passado o período de criação e após quase duas décadas de existência, é necessária uma visão crítica sobre as agências. Propõe-se, então, um método de avaliação regulatória a partir de três variáveis que serão decompostas em diversas subvariáveis (quesitos a serem respondidos objetivamente). A primeira variável, institucionalização, mede as regras aplicáveis à própria agência: características dos mandatos dos dirigentes, autonomia decisória, autonomia financeira e de gestão de pessoal. A segunda, procedimentalização, ocupa-se do processo de tomada de decisão da agência e de sua transparência. Ambas as variáveis procuram medir as agências do ponto de vista formal, a partir de normas aplicáveis (leis, decretos, resoluções, portarias etc.), e pela prática regulatória, com base nos fatos ocorridos demonstrados por meio de documentos oficiais (decretos de nomeação, decisões, relatórios de atividade das próprias agências etc.). A última variável, judicialização, aponta as várias vezes em que a decisão administrativa muda de status e o nível de confirmação dessas decisões pelo Poder Judiciário. O modelo teórico de avaliação das agências ora apresentado é aplicado e testado em três setores que são submetidos à regulação econômica e contam com forte presença de atores sociais e empresa estatal federal. Assim, as agências analisadas foram: Agência Nacional de Energia Elétrica ANEEL, Agência Nacional de Telecomunicações ANATEL e Agência Nacional de Aviação Civil ANAC. Em termos gerais, não é possível garantir a existência de um isoformismo entre essas agências, nem mesmo entre agências criadas em momentos diferentes e por presidentes distintos. Também não foi possível demonstrar que a interferência política seja uma marca de um único governo. A ANATEL, a melhor avaliada das três agências, destaca-se pelo rigor de suas normas que seu processo decisório reflete. A ANEEL e a ANAC tiveram uma avaliação mediana já que apresentaram avaliação sofrível quanto ao processo, mas mostraram ter instituições (regras) um pouco melhores. / The first regulatory agencies were created from the second half of 1900s, and the lasted of them in 2005. With the agencies, emerged regulated private players, users and consumers, and a new approach of interaction between the Executive, Legislative and Judiciary. These actors take part and shape the institutional learning process of agencies. After the creation and over nearly two decades, a critical view is needed on agencies development. It is proposed, therefore, a method of evaluation based on three variables, which will be decomposed into several sub-variables (questions to be answered objectively). The first variable, institutionalization, looks into the rules to which the agency is submitted, as the mandates of the directors, autonomy to take decisions on its own, financial autonomy, and personnel management. The second variable, proceduralizing, deals with the agencys decision-making process and its transparency. Both variables seek to measure the agencies from a formal point of view, based on applicable rules (laws, decrees, resolutions, ordinances, etc.), and the regulatory practice, based on the facts officially documented (appointment decrees, decisions, reports issued by the agencies, etc.). The last sub-variable, judicialization, points out the several times the administrative decision changes status due to judicial review and the level of confirmation of such decisions by the Judiciary. The theoretical model of evaluation of agencies presented here is applied and tested in three sectors that are subject to economic regulation and have a strong presence of social actors and a federal state enterprise. Thus, the agencies analyzed were: Brazilian Electricity Regulatory Agency ANEEL, the Brazilian Telecommunications Agency ANATEL and the Brazilian Civil Aviation Agency ANAC. In general, one cannot assure there is an equal framework between these agencies, even among agencies created at different times and by different presidents. Nor was it possible to demonstrate that political interference is a mark of a single government. ANATEL, the best rated of the three agencies, stands out for the accuracy of its rules, which its decision-making process reflects. ANEEL and ANAC presented poorly assessment regarding the decision-making process, but proved to have institutions (rules) a little stronger.