Dissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. / Made available in DSpace on 2012-10-17T07:52:35Z (GMT). No. of bitstreams: 0Bitstream added on 2016-01-08T23:38:08Z : No. of bitstreams: 1 145051.pdf: 16077467 bytes, checksum: fdc2db0c3fa423f57a7ac62e81a27b59 (MD5)

The rac- and meso- forms of “all carbon” 1,2-diphosphonium dications with the naphthalene -1,8-diyl backbone were synthesised in good yields and purity by double alkylation of the parent diphosphine (1,2-diphenyl-1,2-diphosphaacenaphthene) using strong alkylating agents. Pure rac- and meso- forms of 1,2-diphosphoniums were obtained diastereospecifically by using methyl triflate and trimethyloxonium tetrafluoroborate respectively. It was found that the equilibrium between the rac- and meso- forms at room temperature in acetonitrile solutions effectively depends on the anion present. A reaction mechanism which proceeds via a P-pentacoordinated intermediate was proposed for the epimerisation observed between the rac- and meso- forms in the presence of F⁻ donors in the solution. Reactivity of the new 1,2-dications towards a range of compounds (nucleophiles, bases) was examined and a series of new compounds including phosphine-phosphoniums and phosphonium-phosphine oxides were obtained. Cyclic and acyclic compounds belonging to a novel group of phosphine-arsine mixed peri-substituted acenaphthenes were synthesised by introducing arsenic and phosphorus to the acenaphthene ring, using stepwise lithiation and carbon-group 15 element coupling. All new compounds were fully characterised including single crystal X-ray diffraction. The effect of the peri-substitution by phosphorus moieties and mixed arsine-phosphine peri-substitution on the naphthalene ring was studied using the detailed structural data obtained for these systems.

This thesis studies peri-urban landscapes (the landscape between the rural and urban setting), which has until recently gained little attention in academia and even less in planning practice and policy. This is largely due to a general view of these landscapes as something transient that will be developed in the future. However, some research has recognised these landscapes as important for the leisure and recreation of urban and suburban dwellers. Thus, this thesis is concerned with the current state of the peri-urban landscape, its characteristics and drivers of change with a focus on accessibility. Accordingly, the interest of the study lies in exploring people’s landscape perceptions and uses in relation to the accessibility of periurban areas and how they change over time. The focus of this thesis is Ljubljana and Edinburgh; these two cities have been selected as the case studies in order to elucidate the spatial and social patterns of the space on the edge of the city. The thesis centres on the perspective of inner-city dwellers’ perceptions, use of, and accessibility to peri-urban green spaces. Guided by the sense of place theory and the landscape planning approach, empirical work is at the heart of this research. A mixed-method approach, comprising questionnaire and focus groups with inner-city dwellers, interviews with authorities and planners and GIS-based analysis, is applied to gain new knowledge of inner-city dwellers’ relationship with periurban green spaces. The research found that people greatly value the established peri-urban green spaces, which have a variety of meanings for them, varying according to people’s socio-demographic and cultural characteristics. Furthermore, the appreciation of extensive semi-natural green spaces and green corridors has been shown to be universal and may imply some clues for further spatial planning of these areas. Conversely, people in general did not use the areas with low intrinsic value that are perceived as messy, ambiguous, etc. It appears that these spaces have lost their sense of place and therefore they are under threat of further development. Their future should thus be considered within long-term planning goals, in order to ensure environmentally sustainable and socially inclusive development.

This thesis describes the effect of placing a phosphorus atom in a sterically strained environment with particular emphasis on the geminal disubstitution of two 2,4,6-tri-tert-butylphenyl (Mes*) groups on a single phosphorus centre and intramolecular sub-van der Waals interactions between peri-substituted atoms on naphthalene and acenaphthene. Chapter 2 outlines the reactive chemistry of a sterically encumbered phosphinic chloride (Mes*)₂P(=O)Cl, which was shown to have extremely low reactivity at the phosphorus centre. It has however, been demonstrated that synthetically significant transformations are possible. The phosphine oxide (Mes*)₂P(=O)H and a secondary phosphine Mes*(2,4-tBu₂C₆H₃)PH were obtained from the reduction of (Mes*)₂P(=O)Cl with hydridic reagents under forcing conditions. The corresponding phosphinite was acquired from the deprotonation of (Mes*)₂P(=O)H, which furnished very crowded tertiary phosphine oxides (Mes*)₂P(=O)R (R = Me and Et) on reactions with electrophiles. We have been unable to chlorinate or deprotonate Mes*(2,4-tBu₂C₆H₃)PH, however the reaction with elemental sulfur afforded the affiliated phosphine sulfide Mes*(2,4-[supercript(t)]Bu₂C₆H₃)P(=S)H, albeit under forcing conditions. Our computations (B3LYP and M06-2X level) show that strain energies of geminally substituted compounds are extremely high (180 to 250 kJ mol⁻¹), the majority of the strain is stored as boat distortions to the phenyl rings in Mes* substituents. Chapter 3 describes the strain inherent with non-bonding atomic distances shorter than the sum of their van der Waals radii, specifically heteroatom substitution of the peri-positions of naphthalene and acenaphthene. It also documents the importance of amine protecting groups in chlorophosphine chemistry. The preparation of Ace[P(Ph)N(ⁱPr)₂]Br (Ace = acenaphthene-5,6-diyl) and Ace[P(Ph)N(ⁱPr)₂]₂, plus the elucidation of the molecular structures of Mes*P[N(CH₃)₂]₂, Ace[P(Mes)N(ⁱPr)₂]Br (Mes = 2,4,6-tri-methylphenyl) and Ace[P([supercript(t)]Bu)N(Et)₂]Br sufficiently demonstrate the ring distorting characteristics of structurally encumbered molecules. The reaction of Ace[P(Ph)N(ⁱPr)₂]Br and Ace[P(Ph)N(ⁱPr)₂]₂ with a methylating agent was also investigated.

Abstract Peri-urban areas experience many land related problems and disputes because of rural-urban migration and increasing demand in land. The purpose of this thesis is to identify and describe the land problems and their related disputes that exist in two peri-urban areas surrounding the capital of Botswana, Gaborone. Two land boards administering these areas are studied in order to draw conclusions if there are any improvements that can be made to make the administration of land more effective.   The methods used in this thesis include: a literature review on previous made research to gain sufficient background and knowledge in the subject and a multiple case study to identify the most occurring land problems and how these are handled in the villages of Mogoditshane and Tlokweng. The case study included qualitative interviews with land board officers and experts within the studied subject.   The result from the literature review and the case studies shows similar result when it comes to land problems faced in Mogoditshane and Tlokweng. Common problems such as illegal occupations and multiple transfers lead to disputes over the right to land. The administration of handling these problems differ between the studied land boards as well as the approaches to resolving disputes that arises. For instance in Tlokweng they patrol the village in order to reveal illegal occupations. In the same land board they have also adopted the approach with alternative dispute resolution to reduce number of disputes entering the legal process.   It seems that one of the main causes for the land problems that occur in these areas is poor record keeping. Besides the improvements regarding record keeping, that is already in progress, this study has reached the conclusion that there are several measures that can be taken to make the management of land problems and related disputes more effective. The problem with shortage of land, which is another cause for land problems, could be reduced by an effective and unanimous land allocation process. Further we believe that by training both officers and board members in alternative dispute resolution methods and adopting an approach to try to resolve disputes before becoming a legal matter, will reduce costs as well as save time in the land administration.

A micro infiltração de fluidos bucais e bactérias na interface implante e o intermediário são discutidos na literatura através de várias pesquisas pontuando e determinando que o espaço existente entre os componentes e as conexões dos implantes, chamados de GAP, que parece ser a fonte da infiltração de microorganismos, quer a partir de meio externo para meio interno ou vice versa, resultando em reações inflamatórias nos tecidos periodontais. Portanto, este estudo teve como objetivo analisar um método para evitar e ou pelo menos diminuir micro infiltração na interface implante-intermediário utilizando um material de vedação chamado Loctite® 222 (Henkel Ltda). Este é um material monocomponente, anaeróbico, tixotrópico, de baixa resistência à desmontagem sendo utilizado industrialmente para ajustar os parafusos. Os implantes testados neste estudo foram de três diferentes sistemas de conexão protética: hexágono externo (n = 10), hexágono interno (n = 10) e cone morse (n = 10) e estes foram todos fabricados pela mesma empresa (SIN - Sistema de Implantes). Inicialmente, esses implantes foram utilizados como grupo controle, não recebendo a aplicação do selante na área de conexão. Mini intermediários cônicos foram sentados sobre os corpos dos implantes e o torque foi aplicado seguindo recomendação dos fabricantes. Cada implante foi imerso em um criotubo de 2ml contendo 1,5 ml de BHI estéril. Todos foram inoculados com 250l de Enterecoccus faecalis (ATCC - 29212) no interior do criotubo. Os implantes foram limpos, esterilizados e divididos em 3 grupos testes. Uma fina camada do selante foi aplicada com microbrush sobre a área de conexão antes de encaixar os pilares e logo foi aplicado o torque conforme as recomendações do fabricante. Períodos de avaliação, de 7, 14, 21, 35, 49 e 63 dias foram realizados para analisar a presença de micro infiltração do meio interno dos implantes, seguindo regulamentações específicas no fluxo laminar. Os resultados mostraram a eficácia do material selante quando se compara o grupo controle com os grupos testes. Uma eficácia de 100% foi encontrada para todos os sistemas de implantes estudados, o hexágono externo, hexágono interno e cone morse. / Microbial and fluidic leakage in the implant-abutment interface are shown in literature through a variety of studies, accusing the space that exists between the components of the implant, called \"GAP\", which seems to be the source of the microorganism infiltration, either from the external to the internal environment or the inverse, resulting in inflammatory reactions of the periodontal tissues. Therefore, this study aimed to analyze a method to avoid or at least reduce microleakage at the implant-abutment interface by using a sealing material named Loctite ® 222 (Henkel Ltda). This is a single component, anaerobic, thixotropic, lowstrength threadlocker material industrially used to adjust screws. The implants tested in this study were of three different implant-abutment systems: external hexagon (n=10), internal hexagon (n=10) and morse cone connection (n=10) and these were all manufactured by the same company (SIN - Implant System). Initially, these implants were used as the control group, not receiving the sealant application at the connection area. Mini conical abutments were seated over the implant bodies and torque-tightened to 20 Ncm. Each implant was immersed in a 2ml cryotube containing 1.5 ml of sterile BHI. All implants were inoculated with 250l of Enterecoccus faecalis (ATCC - 29212) inside the cryotube. The same implants were then cleaned, sterilized and divided into 3 test groups. A thin layer of the sealant was applied on the connection area before seating the abutments and proceeding as described before. Evaluation periods of 7, 14, 21, 35, 49 and 63 days were performed to analyze the presence of external contamination of the internal environment, following specific regulations in laminar flow. The results showed the effectiveness of the sealant material when comparing the control group to the test groups. An efficacy of 100% was found for all implant systems studied, the external hexagon, internal hexagon and Morse cone connection.

Many neurological disorders are a result of widespread changes in the excitability of brain tissue. The specific changes in neuronal excitability produces or worsens many of the symptoms associated with these disorders. Pharmacological methods are effective, but their associated side-effects are substantial, and often approximate the severity of the symptoms of the original disorder. The ketogenic diet, a high-fat, low-carbohydrate diet, has been shown to improve many neurological diseases by reducing hyperexcitability without the aforementioned side effects. The current study tested the hypothesis that a ketogenic diet would be associated with alterations in cerebral excitability. Animals were fed either a control or ketogenic diet for at least 21 days prior to experimentation. Power spectral analysis was conducted using EEG data across frequency bands, and compared between diet groups. Current source density analysis was also performed to visualize potential alterations in cerebral excitability.. In the second part of the experiment, a non-invasive ischemic stroke was delivered, and the excitability of the contralateral cortex was monitored. No significant differences were observed between ketogenic and control experiments in regards to overall excitability, although ketogenic diet experiments showed a significantly higher number of acute EEG depressions. No cortical spreading depression events were observed in contralateral recordings. Our findings are in contrast with data showing that ketogenic diets change overall basal excitability, but are in concert with other studies that show that ketogenic diets may not be associated with changes in excitability, but in changes in neuroplasticity.

Despite the availability of contraception in Canada, almost half of pregnancies are unintended and account for approximately 95% of elective, induced abortions. Nearly one-third of Canadian women will access an elective abortion in their lifetime and 30-40% of these women will access at least one further termination. Although contraceptive counselling is generally provided as part of abortion care, there is a paucity of research about the effectiveness of peri-abortive counselling methods or women’s experiences with this care. This research was designed to better understand peri-abortive contraceptive decision-making through the lens of the Ottawa Decision Support Framework and addressed gaps in previous research. The thesis was completed in two parts, a literature review and the first Canadian qualitative study on this topic. Unlike most of the available research that focused on typical outcomes such as contraceptive uptake or continuation, the data from the interpretive descriptive study described women’s informational needs, desired supports, and preferences for peri-abortive contraceptive care. The literature review described the current research and the findings from the qualitative study demonstrated that Canadian women’s experiences with peri-abortive contraceptive care are similar to those in studies published in other countries. This thesis contributes to the limited body of knowledge in understanding what women need and want when receiving contraceptive care as part of abortion services.

Encompassing both urban and rural processes, the peri-urban interface (PUI) provides a unique and challenging arena for environmental management. As the urban core expands, the PUI industrializes and urbanizes, undergoing rapid social, economic, and environmental changes. One of the results of this transformation is often an increase in pollutants and environmental degradation. In the twenty years since the initiation of its reforms towards a more market-oriented economy, Vietnam has seen significant growth, much of this occurring within the industrial sector in and around urban hubs such as Ho Chi Minh City (HCMC). Rapid urbanization and industrialization has occurred with limited control, and a trend has emerged where industrial activity has moved out of the urban core and into the PUI. Despite ongoing efforts, the government of Vietnam, as in other Asian countries, is unable to fully regulate firms illegally releasing untreated and often highly polluted wastewater. The result is that farmers in HCMC’s PUI must now contend with lower crop yields or even failures – and food safety concerns due to an influx of pollutants in irrigation waters. Combining a rights-based approach and a good governance approach, this research describes the constraints on both farmers and government officials that prevent a resolution of farmers’ pollution problems. These constraints are argued to stem from systemic water governance issues in Ho Chi Minh City and Vietnam. They include poor communication between farmers and government officials, limited farmer participation in water management, a lack of integration between government agencies, little government accountability and transparency, and water management priorities that favour economic growth over environmental health. It is argued that strengthening farmers’ water rights could address these issues. However using a rights based approach would first require addressing gender inequities in community affairs, institutional changes to ensure the recognition of farmers’ rights in practice, compensating those harmed by pollution, and educating farmers on the legal system and the water rights it provides. In addition to addressing a general lack of literature on water governance in Vietnam, this research has implications for literature regarding peri-urban environmental management, good water governance, and the rights based approach. This research suggests that the challenges present in the PUI exacerbate and thus illuminate poor water governance practices that extend beyond the local scale. It also suggests that water rights be used as a possible platform to achieve good water governance. Lastly, it explores the potential challenges of implementing a rights based approach.

Encompassing both urban and rural processes, the peri-urban interface (PUI) provides a unique and challenging arena for environmental management. As the urban core expands, the PUI industrializes and urbanizes, undergoing rapid social, economic, and environmental changes. One of the results of this transformation is often an increase in pollutants and environmental degradation. In the twenty years since the initiation of its reforms towards a more market-oriented economy, Vietnam has seen significant growth, much of this occurring within the industrial sector in and around urban hubs such as Ho Chi Minh City (HCMC). Rapid urbanization and industrialization has occurred with limited control, and a trend has emerged where industrial activity has moved out of the urban core and into the PUI. Despite ongoing efforts, the government of Vietnam, as in other Asian countries, is unable to fully regulate firms illegally releasing untreated and often highly polluted wastewater. The result is that farmers in HCMC’s PUI must now contend with lower crop yields or even failures – and food safety concerns due to an influx of pollutants in irrigation waters. Combining a rights-based approach and a good governance approach, this research describes the constraints on both farmers and government officials that prevent a resolution of farmers’ pollution problems. These constraints are argued to stem from systemic water governance issues in Ho Chi Minh City and Vietnam. They include poor communication between farmers and government officials, limited farmer participation in water management, a lack of integration between government agencies, little government accountability and transparency, and water management priorities that favour economic growth over environmental health. It is argued that strengthening farmers’ water rights could address these issues. However using a rights based approach would first require addressing gender inequities in community affairs, institutional changes to ensure the recognition of farmers’ rights in practice, compensating those harmed by pollution, and educating farmers on the legal system and the water rights it provides. In addition to addressing a general lack of literature on water governance in Vietnam, this research has implications for literature regarding peri-urban environmental management, good water governance, and the rights based approach. This research suggests that the challenges present in the PUI exacerbate and thus illuminate poor water governance practices that extend beyond the local scale. It also suggests that water rights be used as a possible platform to achieve good water governance. Lastly, it explores the potential challenges of implementing a rights based approach.