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It is the intent of this paper to review the Acquisition Management SysternVProgram Management concepts of the major Armed Services comprising the Department of Defense (DOD), Army, Navy and the Air Force, and the System Management process associated with System Acquisition. As such, this paper reviews highlights of the DOD Program Management Acquisition Management Systems. The study is closely related to the writer's position at Naval Training Equipment Center. Being a DOD employee and operating in a technical environment, specifically in a position of employing the Program Management concept to in-house major tasks the need for more fully understanding and employing the concepts of Government Programs Management was clearly dictated. At the offset this approach seemed reasonable; however, as the research matured via an intensive literary search a dichothorny in the acquisition System Management process was uncovered. It was also discovered that Government guidelines are undergoing considerable changes, and it became necessary to expend a considerable effort to obtain copies of the applicable material. Research of available reference material was limited to that applicable to Weapon System Acquisition in the pre David Packard era and post David Packard era. Each of the technical management concepts of the Armed Services was reviewed and a summary of each prepared such that a comparative analysis of the three methods could be conducted. The research material was obtained with the assistance of the Navy Technical Library and through purchase of the material from the U. S. Govermnent Printing Office. Every effort has been made to obtain copies of all documents referenced in the Matrix of Major Subsystems and applicable documents of the Department of Defense Acquisition System. These documents are available from this researcher upon request.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering, 2012. / Cataloged from PDF version of thesis. "This study is part of a research project sponsored by EDF at MIT"--P. 3. / Includes bibliographical references (p. 175-178). / During the past twenty-five years, the US Nuclear Regulatory Commission has been progressing toward a more risk-informed, performance-based regulation. This regulatory framework has effectively supported the development of online maintenance practices. In France, while the safety authority has been encouraging particular risk-informed applications, PRA (Probabilistic Risk Assessment) techniques have not penetrated the nuclear regulatory framework and industry to the same extent. After presenting relevant differences between the French and US nuclear industries and regulatory frameworks, the development and use of risk-informed applications in both countries are reviewed. In the United States, these techniques are usually well-accepted and have brought positive results regarding operational performance, plant safety and regulatory efficiency. In France, there have been in some cases difficulties regarding the acceptability of these techniques with the safety authority, but also within the operating company. While PRA results are commonly used in the US at the operational level through the use of risk-monitors, there appear to be in France obstacles to such practices. Online maintenance regulations and practices are then presented. US technical specifications provide much flexibility to voluntarily enter technical specifications action statements for online maintenance. As a result, following the implementation of the Maintenance Rule, online maintenance has been increasingly applied, leading to operational as well as safety improvements. In France technical specifications are more restrictive regarding these aspects, and online maintenance of safety-significant systems is often not allowed or allowed under restrictive conditions. A case study concerning the maintenance of emergency diesel generators and emergency core cooling systems is presented to illustrate and study these points in more detail. Finally, possible directions to facilitate the implementation of an online maintenance strategy in France are identified, and their implications are discussed. / by Edouard Verdier. / S.M.

Thesis (S.M. in Engineering and Management)--Massachusetts Institute of Technology, Engineering Systems Division, System Design and Management Program, 2011. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 113-121). / Many US Department of Defense (DoD) systems operate within a systems of systems construct, which present many challenges and will be ever increasing for test and evaluation of unmanned autonomous systems of systems. Challenges include emergent behaviors along with resource limitations that will cause test planners to balance tradeoffs in order to effectively plan test missions. The current test and evaluation enterprise will have to change in order to address such challenges. This thesis investigates how a decision support system can be utilized by DoD test and evaluation stakeholders to adequately plan missions for unmanned autonomous systems of systems testing. Research was conducted to serve dual strategic and tactical purposes. Strategically, this research served to identify potential gaps in the test and evaluation enterprise, which create challenges for unmanned autonomous systems of systems testing. Tactically, this research investigated how a decision support system can deliver value to the stakeholders of the enterprise. This effort was guided by five research focus areas. First, focus was on differentiating testing at the system and systems of systems levels. Second, test and evaluation stakeholders were identified and their saliency was determined. Third, stakeholder values for testing of unmanned systems were gathered via stakeholder interviews. Fourth, challenges of testing unmanned autonomous systems of systems were determined. Lastly, a use case example was utilized to demonstrate how stakeholder value is generated by the use of a decision support system. / by Karl K. Cowart. / S.M.in Engineering and Management

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Fusobacterium are Gram-negative anaerobic bacteria that colonize a variety of eukaryotes including cattle and humans. In humans, Fusobacterium coordinates the central architecture of the oral biofilm by expressing an abundance of outer membrane adhesins that mediate bridging between early and late colonizing bacteria. While Fusobacterium are mostly considered commensal microorganisms, they can also become an opportunistic pathogen that spreads throughout the human body and promote the development of oral and extra-oral infections and diseases including colorectal cancer. Importantly for this work, many Fusobacterium species and strains are recalcitrant to genetic manipulation, the majority of which has led to hindrance in the study of their biology, molecular mechanisms, and pathogenesis. The genetic intractability of Fusobacterium is an obstacle for the development of future treatments for diseases associated with these anaerobic bacteria. Therefore, the creation of tools to enhance genome editing in target species is crucial to understand the molecular mechanisms driving Fusobacterium infections. This dissertation exploits innate and adaptive defense systems present in Fusobacterium for their use as molecular tools for genome editing. Accordingly, we first investigated restriction-modification systems with a focus on the role of DNA methyltransferases and endonucleases in host defense and genetic recalcitrance in several strains of Fusobacterium through bioinformatic and biochemical approaches. Altogether, over 15 DNA methyltransferases were characterized. Most notably, we identified and characterized two type II DNA methyltransferases that are capable of methylating plasmid DNA by treating with purified enzymes in-vitro and coexpression approaches in Escherichia coli strains, enabling an statiscally improved transformation efficiency via electroporation in F. nucleatum. Also contained in this dissertation is the first detailed description of CRISPR-Cas adaptive immunity systems present in Fusobacterium strains. Most of the discovered CRISPR-Cas systems in Fusobacterium belong to Class 1 systems. Nonetheless we identified Type II-A and Type VI-C Class 2 systems. The discovery of Cas9 and Cas13c effectors respectively from these systems will be crucial in the development of a new generation of genome-editing tools in Fusobacterium. The studies included in this dissertation provide the framework for overcoming Fusobacterium genetic recalcitrance by the implementation of host mimicking techniques. By utilizing restriction-modification system enzymes and the adaptive immunity CRISPR-Cas systems, we will gain a better understanding of how Fusobacterium modulates infections and diseases, and ultimately explore the potential of novel therapeutic treatments. / Doctor of Philosophy / The oral cavity has one of the most diverse and largest microbial populations, where microorganisms are capable of colonizing hard surfaces of the teeth and the soft tissues of the oral mucosa. A fundamental member of the oral microbiome is Fusobacterium, a Gram-negative bacterium which coordinates the oral biofilm formation by interacting with other microorganisms. In recent studies, Fusobacterium has been associated with oral and extra-oral infections and diseases including periodontitis, preterm birth, Lemiere syndrome, inflammatory bowel disease and colorectal cancer. Importantly, many Fusobacterium species and strains are challenging to study due to their inability to uptake exogenous DNA and lack of genetic tools, which has hindered the study of their biology, molecular mechanisms and pathogenesis. The challenges in the genetic manipulation of Fusobacterium present a significant obstacle for the development of future treatments for diseases associated with these bacteria. Therefore, the creation of tools to expand bacterial transformation of exogenous DNA and genome editing to more than just one Fusobacterium species is crucial to understand how Fusobacterium is causing these infections. This dissertation explores the presence and utilization of defense systems, which defend bacteria from phage attack, as an alternative to improve Fusobacterium genetics. Accordingly, we first studied a set of over 15 enzymes that recognize a specific DNA pattern and add a methyl group (DNA methyltransferases) to specific nucleotides in several strains of Fusobacterium. We discovered that two of these enzymes improve Fusobacterium's ability of importing and genomically incorporating exogenous DNA after an electric discharge permeabilizes the bacterial membrane. Furthermore, for the first time we have described the composition of CRISPR-Cas bacterial defense systems, that detect invading DNA from viruses and provide protection to Fusobacterium strains. These systems have previously been successfully used as genetic tools to achieve genome editing. Thus, their further characterization is warranted to create novel molecular tools in Fusobacterium. Altogether, these discoveries will lead to a better comprehension of Fusobacterium biology in infections and diseases, while exploring novel therapeutic strategies.

The parasitic angiosperm Orobanche aegyptiaca (Pers.) (Egyptian broomrape) is a root holoparasite that causes severe losses in yield and quality of many crops. Control of Orobanche is extremely challenging, in part because the parasite is hidden underground for most of its life cycle. However, the dependence of the parasite on the host suggests that broomrape-resistant hosts could be an ideal control method. Genetic engineering strategies may facilitate realization of this goal, but require an understanding of host defense responses to parasitism. Previous studies with tobacco indicated that broomrape parasitism induces host genes associated with jasmonic acid (JA)-mediated defenses such as wound responses and localized production of phenylpropanoid and isoprenoid phytoalexins. However, the gene for the pathogenesis-related (PR) protein, PR-1a, was not induced by parasitism in tobacco. Expression of PR-1a is correlated with the salicylic acid (SA)-mediated defense pathway that leads to systemic acquired resistance (SAR). The objective of this research was to extend the characterization of PR gene expression in order to define the scope of host defense response. Analyses of gene expression using RNA hybridization and RT-PCR in broomrape-parasitized Arabidopsis thaliana roots indicated that PR-1, PR-2, PR-5, as well as the JA-associated PDF1.2, were slightly induced by parasitism. Expression of PR-1, PR-5, and PDF1.2 in parasitized roots was not detectable by RNA hybridization analysis, but was demonstrated by RT-PCR. Interestingly, shoots of the parasitized plants showed greater PR gene expression levels than roots, indicating that O. aegyptiaca induced a response in the host that was systemic and amplified in shoots. Microarray analysis of parasitized Arabidopsis roots demonstrated a broad range of host gene expression changes including both defense- and non-defense-related genes. Genes induced were consistent with O. aegyptiaca preferentially stimulating JA-mediated responses. The failure of O. aegyptiaca to elicit SA-mediated defenses in host roots suggested that exogenous induction of this signaling pathway could enhance host resistance to parasitism. Treatment of O. aegyptiaca-inoculated tobacco with BTH, a SA analog that activates SAR, caused a 49% reduction in O. aegyptiaca numbers. Analysis of PR-1a using RNA hybridizations and protein immunoblots in treated plants showed the expected induction in shoots, but not in roots, confirming the organ-specific differences in defense response observed in Arabidopsis. Experiments using a strategy to engineer the hypersensitive response via the gene-for-gene interaction confirmed previous findings that parasite-specific activation of an R/Avr interaction in tobacco reduced parasitism by approximately 50%. This research suggests that approaches to stimulate SAR in susceptible host plants may be useful for reducing Orobanche parasitism / Master of Science

This study tested the hypotheses that perceived risk of victimization had a stronger effect than actual exposure to victimization risk on handgun ownership and that this relationship was stronger for women than men. Perceived and actual risks of victimization have been discussed with respect to handgun ownership, but a general consensus in the literature was lacking and recent empirical research was scarce. Crime rates and respondents' social characteristics were used as proxy measures for victimization risk, while fear of crime measured perceived risk of victimization. Three sets of models were estimated, the first with a pooled sample of men and women, the second and third on samples separated by gender. Binary logistic regression was utilized to compare the predictive power of these two major correlates of handgun ownership and observe how their effects varied by gender. Data were drawn from the National Opinion for Research Center's (NORC) Cumulative General Social Surveys (GSS) for the years 1986 through 2008. Predictors of victimization risk, especially gender and regional crime rate, had strong effects on handgun possession, while perceived risk had no effect on handgun possession. Results also demonstrated that while women were more likely to fear crime, they were not necessarily more or less likely than men to obtain handguns in response to that fear. / Master of Science