Spelling suggestions: "subject:"code""
11 |
Tandem reactions involving hydroxylamine-alkyne cyclisationsDavison, Edwin Christopher January 1995 (has links)
No description available.
|
12 |
Intermolecular Cope-Type Hydroamination with Boron-Containing SpeciesVolosheniuk, Myroslava 12 September 2022 (has links)
Advances in synthesis of boron-containing molecules significantly enlarged the usage of boron-containing subunits in medicinal chemistry. Interestingly, few recently approved drugs are boron analogues of natural amino acid derivatives. They contain an aminoboronic subunit. This subunit is also known to serve as a useful synthetic intermediate. However, despite its unique properties, limited examples of its synthesis are reported.
In this work, a new method of obtaining aminoboronic acids derivatives is discussed. In Chapter 2 conditions towards obtaining β-aminoboronic acid derivatives via anti-Markovnikov Cope-type hydroamination are presented. Cope-type hydroamination with boron containing species have shown to proceed at lower temperatures compared to unsubstituted alkene derivatives. The products of Cope-type hydroamination reaction are new: to our knowledge similar oxazaborolidine heterocycles have not been reported. Despite reduced stability of the synthesised products and their proneness to conduct bora-Cope type elimination reaction, it was possible to demonstrate oxazaborolidine synthetic utility by various derivatization reactions. A scope with primary and secondary hydroxylamines is presented for a vinylboronate substrate.
This work required access to a range of hydroxylamines. Recently our group discovered simple conditions to oxidize amines to hydroxylamines. In Chapter 3 an investigation of isolation conditions for a variant of this newly developed hydroxylamine synthesis is presented. While the oxidation is generally efficient in the presence of excess amine, the main challenge proved to be the propensity of the unreacted amine and hydroxylamine product to interact together. The efficiency and main limitations of different isolation strategies are presented. In general, the best results of removal of the excess amine via filtration were obtained using oxalic acid to form the corresponding amine salt. This filtration was followed by a short silica plug to further remove the amine salt causing contamination.
|
13 |
Alumina-catalyzed Cope rearrangementWang, Paul Jhy-Shing 01 January 1974 (has links)
The alumina-catalyzed Cope rearrangements of meso- and dl-3,4-diphenylhexa-1,5-diene were examined in detail, following up a preliminary observation by H. Berg at Portland State University. Commercial column-chromatography grade alumina was employed, and was further activated before use.by heating at 650-700° for four hours.
Using a ratio of 20 mg of dl-3,4-diphenylhex-l,5-diene to 1 g of alumina in heptane, the Cope rearrangement was complete within 15 minutes at room temperature to give exclusively trans,trans-1,6-diphenylhexa-1,5-diene. This was identified.by melting point, infrared spectroscopy and vapor phase chromatography
The catalyzed rearrangement of meso-3,4-diphenylhexa-l,5-diene was run using the same diene to alumina ratio. It was found that 31% of the meso-diene was converted to cis,trans- and trans,trans-l,6-diphenylhexa-1,5-diene at room temperature in four hours. Product iso-merization appeared to take place; the initial ratio of cis,trans-diene to trans,trans-diene was estimated to be 73:27. Another run was carried out at 60°, where the problem of isomerization of cis,trans-diene to trans,trans-diene was more pronounced. The rearrangement gave cis, trans-diene and trans,trans-diene in a ratio of 58:42, as estimated by extrapolation of the product ratio to zero time. Approximately 95% of meso-diene had reacted in one hour at this temperature. The extent of conversion of mes-diene was calculated by quantitative infrared spectroscopy, and the isomeric distribution of products was determined by vapor phase chromatography.
The product distribution in the alumina-catalyzed rearrangements parallels that of the thermal Cope rearrangement, where dl-diene gives exclusively trans,trans-diene at 80° with a half-life of eight hours and meso-diene gives 63% cis,trans-diene and 27% trans,trans-diene at 120° with a half-life of 15 hours.
|
14 |
HOW COPING, PTSD, AND TREATMENT PREFERENCES INTERACT?Golubski, Martha Mae 13 June 2014 (has links)
No description available.
|
15 |
Faire face ou vivre avec les catastrophes ? Capacités d'adaptation et capabilités dans les trajectoires de résilience individuelles et territoriales au sein de l'espace Caraïbe / Coping or living with disasters? Adaptive capacities and capabilities in individual and territorial resilience trajectories within the Caribbean areaBénitez, Fanny 21 September 2018 (has links)
La notion de cope with souvent traduite en France par l’expression « faire face », est régulièrement utilisée pour définir et expliquer la vulnérabilité et la résilience des sociétés. L’opérationnalisation de cette notion s’accomplit grâce aux coping capacities. Les cadres internationaux de prévention et de gestion insistent sur la nécessité de développer ces capacités à l’échelle des communautés et des territoires, en préparant les individus à « faire face », afin de réduire leur vulnérabilité et les rendre résilients.Le cope with n’a pourtant jamais été clairement décrit et surtout défini dans la littérature scientifique. En partant de ce constat, cette thèse va chercher à comprendre les liens existants entre la vulnérabilité, le cope with et la résilience. Pour cela, la recherche s’appuie sur l’étude des trajectoires de résilience territoriales et individuelles dans le contexte caribéen. Trois terrains d’étude, qui ont subi chacun des crises majeures, ont été choisis : La Martinique, La Guadeloupe et Haïti. L’enquête de terrain s’est appuyée sur la collecte de récits de vie, sur des entretiens et des questionnaires, sur de l’observation participante et non participante mais aussi sur un travail d’archives.Cette thèse démontre plusieurs résultats. Premièrement, les trajectoires de résilience territoriales ne coïncident pas avec les trajectoires de résilience individuelles. La résilience du territoire n’implique pas forcément celle de ses habitants et inversement. La thèse spécifie ici les différents états que peut prendre la résilience territoriale et individuelle et revient sur les notions de crise et de catastrophe. Ensuite, le cope with peut être appréhendé grâce aux réponses que les gens mettent en œuvre face aux perturbations. Ces réponses font l’objet d’une typologie, puis sont réinterprétées grâce aux notions d’ajustement et d’adaptation, ce qui permet de revenir sur la traduction du cope with. La thèse montre enfin qu’il n’y a pas de causalité linéaire entre la mise en œuvre des coping capacities des individus, les réponses observées et la résilience. L’approche par les capabilités, développée par A. Sen, est alors appliquée au champ des risques et des catastrophes. Elle permet de montrer l’importance des choix et de la liberté individuelle, et de recontextualiser le cope with. Cette thèse propose alors de remplacer la notion de coping capacities par celle de coping capabilities, pour comprendre comment chaque individu « fait face », dans une situation précise, dans un contexte territorial précis et dans une temporalité particulière à un événement singulier. / The notion of cope with, often translated in french by the expression "faire face", is usually used to define and explain the vulnerability and resilience of societies. This concept is made effective through coping capacities. International prevention and management frameworks emphasize the need to develop these capacities at the community and territorial scales by preparing individuals to "cope" in order to reduce their vulnerability and make them resilient.However the notion of cope with has never been clearly described and defined in scientific literature. Based on this observation, this thesis aims at understanding the existing links between vulnerability, cope with and resilience. To this end, the research is based on the study of territorial and individual trajectories of resilience in the Caribbean context. Three study areas which has suffered major crises, have been chosen : Martinique, Guadeloupe and Haiti. The investigation was based on the collection of life stories, interviews and questionnaires, participant and non-participant observation and archival work.This thesis demonstrates several results. First, territorial resilience trajectories do not coincide with individual resilience trajectories. The resilience of the territory does not necessarily imply the resilience of inhabitants and inversely. The thesis here specifies the different states that territorial and individual resilience can take on and goes back over the notions of crisis and disaster. Then, the notion of cope with can be grasped thanks to the answers that people implement in the face of disturbances. These answers are the subject of a typology, then reinterpreted thanks to the notions of adjustment and adaptation, which makes it possible to return to the translation of the cope with. Finally, the thesis demonstrates that there is no linear causality between the implementation of individuals' coping capacities, observed responses and resilience. The capability approach developed by A. Sen is then applied to the area of risks and disasters. It shows the importance of individual choices and freedom, and to recontextualize the notion of cope with. This thesis proposes then to replace the notion of coping capacities by the concept of coping capabilities, to understand how each individual "cope with", in a precise situation, on a given territory and in a particular temporality.
|
16 |
Validation of a coping scale in an African context / Carelyn van der WaltVan der Walt, Carelyn January 2007 (has links)
Thesis (M.A. (Psychology))--North-West University, Potchefstroom Campus, 2008.
|
17 |
Validation of a coping scale in an African context / Carelyn van der WaltVan der Walt, Carelyn January 2007 (has links)
Thesis (M.A. (Psychology))--North-West University, Potchefstroom Campus, 2008.
|
18 |
Validation of a coping scale in an African context / Carelyn van der WaltVan der Walt, Carelyn January 2007 (has links)
Thesis (M.A. (Psychology))--North-West University, Potchefstroom Campus, 2008.
|
19 |
Targeting educator resilience : an intervention program for Free State primary school educators affected by the HIV/AIDS pandemic / Moeketsi, Ntsubise VioletMoeketsi, Ntsubise Violet January 2010 (has links)
The aim of this study was to explore how effectively educators in primary schools in the Thabo Mofutsanyana district (rural QwaQwa area, Free State province) affected by the HIV/AIDS pandemic can be supported to cope more resiliently with the pandemic's challenges, using the Resilient Educators programme (REds). REds has been piloted with urban educators previously, but not with rural educators. In order for me to achieve this aim, I used mixed methods to gather data: qualitative and quantitative data were gathered in the pre- and post-tests (before and after the implementation of REds) to comment on participant empowerment. I interpreted the data to comment on whether and how the REds programme supported educators affected by HIV/AIDS. Previous Reds piloting was done with urban educators. My piloting would explore if and how
REds would enable rural educators. To actualise the study, I recruited ten participants (two males and eight females), but only the eight females completed the study. My participants were Sesotho-speaking educators frorn one of the primary schools in the rural area in the Thabo Mofutsanyana district (QwaQwa area) and all were affected by the pandemic. My findings indicated that REds was a meaningful intervention, but that it needs to be improved as regards the following: • Facilitators should take note of the strengths that participants have relating to HIV/AIDS. • Future REds should encourage positive interpersonal relationships. • The entire staff and different stakeholders in the community should be involved in future REds participation. • REds should be an ongoing intervention strategy for supporting infected educators and those otherwise affected by the pandemic. / M.Ed., North-West University, Vaal Triangle Campus, 2010
|
20 |
Targeting educator resilience : an intervention program for Free State primary school educators affected by the HIV/AIDS pandemic / Moeketsi, Ntsubise VioletMoeketsi, Ntsubise Violet January 2010 (has links)
The aim of this study was to explore how effectively educators in primary schools in the Thabo Mofutsanyana district (rural QwaQwa area, Free State province) affected by the HIV/AIDS pandemic can be supported to cope more resiliently with the pandemic's challenges, using the Resilient Educators programme (REds). REds has been piloted with urban educators previously, but not with rural educators. In order for me to achieve this aim, I used mixed methods to gather data: qualitative and quantitative data were gathered in the pre- and post-tests (before and after the implementation of REds) to comment on participant empowerment. I interpreted the data to comment on whether and how the REds programme supported educators affected by HIV/AIDS. Previous Reds piloting was done with urban educators. My piloting would explore if and how
REds would enable rural educators. To actualise the study, I recruited ten participants (two males and eight females), but only the eight females completed the study. My participants were Sesotho-speaking educators frorn one of the primary schools in the rural area in the Thabo Mofutsanyana district (QwaQwa area) and all were affected by the pandemic. My findings indicated that REds was a meaningful intervention, but that it needs to be improved as regards the following: • Facilitators should take note of the strengths that participants have relating to HIV/AIDS. • Future REds should encourage positive interpersonal relationships. • The entire staff and different stakeholders in the community should be involved in future REds participation. • REds should be an ongoing intervention strategy for supporting infected educators and those otherwise affected by the pandemic. / M.Ed., North-West University, Vaal Triangle Campus, 2010
|
Page generated in 0.0551 seconds