Detailed analysis of the site-specific phosphorylation of a glucan phosphate from Saccharomyces cerevesiae has been carried out by 2D NMR techniques. Phosphorylation has been shown to be limited to the C-6 and C-2 positions, with the C-6 resonance showing two slightly different environments. Phosphorylation at C-4 is hindered due to proximity effects with the neighboring glucose ring oxygen. Noncovalently bound, nondialyzable phosphate appears to be coordinated to the nonphosphorylated HO-2 group of the helical polymer.

Polyketides are a class of natural products that exhibit remarkable structural and functionally diversity and are highly sought after due to their medicinally important activities. For many decades now, polyketide synthases (PKSs), the mega-enzymes responsible for biosynthesis of polyketides have been the focus of extensive investigation to make new polyketides by polyketide engineering strategies. While there are many established methods to investigate polyketide enzymes and biosynthesis mechanisms, they have substantial shortcomings that have limited the extent of success with polyketide engineering efforts. This thesis focuses on developing simple, flexible yet powerful tools for examining polyketide biosynthesis by overcoming some deficiencies in currently used techniques. Reactive heterocylces have been designed for direct labeling of key polyketide synthase enzymes to provide a direct insight into its functions and mechanisms. First β-lactones and then β-lactams have been used as small molecule probes to perform site-specific labeling of acyl carrier proteins and further used for mechanistic interrogation of key steps in polyketide biosynthesis. The utility of these probes has been demonstrated by comparison to traditional probes and has been successfully applied to examine substrate selectivity of keto synthases, key enzymes in polyketide biosynthesis. The applications of the tools described in this manuscript only scratch the surface of their capabilities and are expected to significantly aid in the study of new and existing PKS systems leading to improved understanding of how these extraordinary biosynthetic machines function.

No description available.

Polychlorinated biphenyls (PCBs) are persistent organic pollutants, which were banned several decades ago but still exist in the environment, posing a threat to human health. Previously, joint sealants containing PCBs were used in construction. In this study, the long-term PCB-contaminated soils were from a residential area in Västerås Municipality, where the PCBs have been leaching from buildings to the soil for several years. The objective of this thesis is to investigate the feasibility of using plants to remove PCBs from the contaminated soil at a greenhouse scale, and to use a site-specific guideline model for the risk assessment of this contaminated site. After a literature review, four plant species were selected for the greenhouse cultivation including alfalfa (Medicago sativa L.), white clover (Trifolium repens L.), horseradish (Armoracia rusticana L.) and tobacco (Nicotiana tobacum L.). The plants cultivated in the greenhouse were maintained for 92 days and then the concentrations of PCBs in the initial and remediated soils were analyzed by GC-MS. The results indicate that the selected plant species can enhance the removal of high chlorinated PCBs from soils. In the risk assessment, the contents of PCBs in soils were higher than the calculated site-specific guideline, which means it is urgent to implement measures for protecting residents’ health.

A goal of indoor wireless communication is to strategically place RF base stations to obtain optimum signal coverage at the lowest cost and power. Traditionally, transceiver locations have been selected by human experts who rely on experience and heuristics to obtain a near-optimum placement. Current methods depend on involved on-site communication measurements and crude statistical modeling of the obtained data which is time consuming and prohibitive in cost. Given the inherent variability of the indoor environment, such a method often yields poor efficiency. As an example, it is possible that more power than required or extra number of transceivers were used. This thesis describes an interactive software system that can be used to aid transceiver placement. The tool is easy to use and is targeted at users who are not experts in wireless communication system design. Once the transceiver locations are selected by the user within a graphical floor plan, the system uses simple path-loss models to predict coverage regions for each transceiver. The coverage regions are highlighted to indicate expected coverage. Earlier work assumed isotropic transceivers and had limited directional transmitter support. This thesis describes how the tool has been enhanced to support a wide range of 3D antenna patterns as encountered in practical situations. The tool has also been expanded to accommodate more partition types and to report area of coverage. The resulting system is expected to be very useful in the practical deployment of indoor wireless systems. / Master of Science

O estudo a seguir desdobra as questões de site specificity na arte contemporânea e suas modificações nas três últimas décadas. A compreensão do espaço em arte tomou novas formas não só em função dos espaços e dos discursos artísticos, mas também em função dos novos meios e linguagens. Essas mudanças demandaram alguns acompanhamentos por parte dos espaços expositivos, bem como um novo olhar sobre o que se entende por site specific art. Com base, principalmente nas propostas de Miwon Kwon, o presente material compara as obras de arte contemporânea, tecendo diálogos com as mudanças vistas. Espaços institucionalizados, como Inhotim, dialogam com a noção de site specificic arts, demonstrando as observações sobre site specificity. A pesquisa apresenta esta jornada e fornece subsídios para vislumbrar o espaço da arte contemporânea na segunda década do século XXI. / The following research unfolds site specificity matters on contemporary art and its changes for the last three decades. The comprehension of the space in art had reached new standards, not only due to artistic spaces and discourses, but also for new media and languages. Theses changes demanded some accomplishments at the exhibition spaces as well as new looks over what one understands as site specific art. Upon Miwon Kown premisses this study compares contemporary art works creating dialogs with the modifications already achieved. Institutionalized spaces, such as Inhotim, converse with site specific arts, what reinforces the need for a site specificity stare. The probe validates the jouney and endorses a fresh look over contemporary art on the second decade of the 21st century

A partir de um olhar e de uma escuta direcionadas à cidade, objetivou-se a experiência do corpo no espaço urbano por meio do caminhar como ação poética capaz de suscitar um corpo-crítico que percebesse na paisagem e na arquitetura dos mobiliários urbanos instalados os ideais de cerceamento que fomentam os desequilíbrios sociais e a segregação urbana. A metodologia utilizada inspirou-se na flanerie na cidade, com um mapeamento do uso de espaços públicos, seguido de levantamento das arquiteturas dos mobiliários urbanos, para que as mesmas fossem Re-projetadas, além da coleta feita da paisagem sonora do lugar. Buscou-se assim revelar as segregações, brechas e vazios produzidos por uma anti-arquitetura que cauteriza a experiência sensorial de imersão do corpo na cidade quando estas revelam, na escala fílmica aqui proposta, a solidão e angústia, frutos da leitura de uma cidade fragmentada pelo desenho urbano de onde os vazios, as ausências e o caos engolfam a vida, anulando a experiência do corpo na cidade. / From a direct observation and an attentive listening to the city, this research emphasizes the experience of the body in the urban space taking the act of walking as poetical action as a means to excite a critical-body that could perceive in the landscape and in the architecture of the urban furniture installed the method of clipping ideals that foment social unbalance and urban segregation. The methodology used was inspired in flanerie in the city, with a mapping of the use of public spaces, followed by a survey of the architectures of the urban furniture, so that the same ones were re-projected, beyond the collection of the sonorous landscape of the place. One thus searched to disclose to the segregations, breaches and emptinesses produced by an anti-architecture that cauterizes the sensorial experience of immersion of the body in the city when these polarize on the filmic scale disclosing to the solitude and anguish, fruits of the reading of a city broken up for the urban drawing from where the emptinesses, the absences and the chaos engulf life, annulling the experience of the body in the city.

A partir de um olhar e de uma escuta direcionadas à cidade, objetivou-se a experiência do corpo no espaço urbano por meio do caminhar como ação poética capaz de suscitar um corpo-crítico que percebesse na paisagem e na arquitetura dos mobiliários urbanos instalados os ideais de cerceamento que fomentam os desequilíbrios sociais e a segregação urbana. A metodologia utilizada inspirou-se na flanerie na cidade, com um mapeamento do uso de espaços públicos, seguido de levantamento das arquiteturas dos mobiliários urbanos, para que as mesmas fossem Re-projetadas, além da coleta feita da paisagem sonora do lugar. Buscou-se assim revelar as segregações, brechas e vazios produzidos por uma anti-arquitetura que cauteriza a experiência sensorial de imersão do corpo na cidade quando estas revelam, na escala fílmica aqui proposta, a solidão e angústia, frutos da leitura de uma cidade fragmentada pelo desenho urbano de onde os vazios, as ausências e o caos engolfam a vida, anulando a experiência do corpo na cidade. / From a direct observation and an attentive listening to the city, this research emphasizes the experience of the body in the urban space taking the act of walking as poetical action as a means to excite a critical-body that could perceive in the landscape and in the architecture of the urban furniture installed the method of clipping ideals that foment social unbalance and urban segregation. The methodology used was inspired in flanerie in the city, with a mapping of the use of public spaces, followed by a survey of the architectures of the urban furniture, so that the same ones were re-projected, beyond the collection of the sonorous landscape of the place. One thus searched to disclose to the segregations, breaches and emptinesses produced by an anti-architecture that cauterizes the sensorial experience of immersion of the body in the city when these polarize on the filmic scale disclosing to the solitude and anguish, fruits of the reading of a city broken up for the urban drawing from where the emptinesses, the absences and the chaos engulf life, annulling the experience of the body in the city.

Esta dissertação tem por objetivo analisar o trabalho artís tico Projeto para a Ocupação de uma Casa, realizado dentro do programa de mestrado em Poéticas Visuais entre 2004 e 2005. Através desse trabalho pretendeu-se compreender e aprofundar o interesse no ambiente doméstico presente na produção que o antecedeu. Para isso, foi feita uma revisão crítica dessa produção, onde foram identificados os principais assuntos, recursos e problemas que formaram o interesse no ambiente doméstico. Essa revisão constitui a primeira parte desta dissertação. Na segunda parte, é analisado o Projeto. Partindo de um conjunto de referências prioritariamente literárias, uma série de objetos foi elaborada para ocupar cada um dos cômodos de uma casa escolhida, de modo que, ao percorrê-la, uma narrativa de caráter ficcional se formava. No texto, verificam-se as intenções e resultados de cada peça e ambiente; se elas cumpriram a meta de aprofundamento e entendimento da questão doméstica, as suas soluções formais, os sentidos que engendraram e o papel que desempenharam na constituição da narrativa. / The objective of this thesis is to analyze the art work Project for the Occupation of a House, which was developed within the masters program in Visual Poetics, between 2004 and 2005. The thesis has aimed at understanding and deepening the interest in the domestic environment that was present in the production that preceded it. In order to achieve this, a critical review of the production was carried out, in which the main subjects, resources and problems involved in the interest in the domestic environment were identified. This review constitutes the first part of the thesis. In the second part, the Project is analyzed. With the background of a number of primarily literary references, a series of objects was elaborated to occupy each of the rooms of a chosen house, in a way that as the house was visited, a narrative of fictional character was formed. In the text, the intentions and results of each piece and surrounding are checked: whether or not they have achieved the result of deepening the understanding of the domestic question, their formal solutions, the meanings that were generated, and the role they played in the cons titution of the narrative.

O estudo a seguir desdobra as questões de site specificity na arte contemporânea e suas modificações nas três últimas décadas. A compreensão do espaço em arte tomou novas formas não só em função dos espaços e dos discursos artísticos, mas também em função dos novos meios e linguagens. Essas mudanças demandaram alguns acompanhamentos por parte dos espaços expositivos, bem como um novo olhar sobre o que se entende por site specific art. Com base, principalmente nas propostas de Miwon Kwon, o presente material compara as obras de arte contemporânea, tecendo diálogos com as mudanças vistas. Espaços institucionalizados, como Inhotim, dialogam com a noção de site specificic arts, demonstrando as observações sobre site specificity. A pesquisa apresenta esta jornada e fornece subsídios para vislumbrar o espaço da arte contemporânea na segunda década do século XXI. / The following research unfolds site specificity matters on contemporary art and its changes for the last three decades. The comprehension of the space in art had reached new standards, not only due to artistic spaces and discourses, but also for new media and languages. Theses changes demanded some accomplishments at the exhibition spaces as well as new looks over what one understands as site specific art. Upon Miwon Kown premisses this study compares contemporary art works creating dialogs with the modifications already achieved. Institutionalized spaces, such as Inhotim, converse with site specific arts, what reinforces the need for a site specificity stare. The probe validates the jouney and endorses a fresh look over contemporary art on the second decade of the 21st century