Cette thèse a été consacrée tout d'abord à l'étude du premier procédé domino méthylénation-hydrogénation des aldéhydes et des cétones. Ce processus repose sur la combinaison d'un réactif gem-bimétallique [CH2(ZnI)2] et un catalyseur de Wilkinson (ClRh(PPh3)3) en présence d'hydrogène moléculaire.L'étendue et les limites de cette réaction ont été explorées. Ensuite, l’étude de la réaction de semi-hydrogénation antid'alcynes par catalyse homogène a permis d’accéder de façon stéréosélective aux alcènes (E) correspondants. Cette réaction a été développée en utilisant des réactifs commerciaux et peu couteux : Zn0, ZnI2 et Cl2Pd(PPh3)2sous1 atmosphère d’hydrogène moléculaire. Ces conditions sont à ce jour les plus douces utilisées pour cette réaction.Finalement, la préparation d’imidates par condensation de furfurylamine sur une variété d’iminoester, et la synthèse d’amidines par la condensation d’amines primaires sur les imidates précedemment obtenus, ont été réalisées. L’évaluation de l’activité anti-oxydante des nouveaux composés formés (imidates et amidines) a donnée des résultats prometteurs. / During this research, the firstmethylenation-hydrogenation domino process of aldehydes and ketones has been studied. This process is based on the combination of a gem-bimetallic reagent [CH2(ZnI)2] and a Wilkinson catalyst (ClRh(PPh3)3). The scope and limitations of this reaction have been explored.Furthermore, the semi-hydrogenation antiof internal alkynes by homogeneous catalysis allowed stereoselective access to the corresponding alkenes (E). This reaction was developed using commercially available and low expensive reagents: Zn0, ZnI2 and Cl2Pd(PPh3)2under H2 atmosphere. The use of easy handle and soft conditions had been first described.Finally, two synthetic routes were used to prepare imidates and amidines. The first were obtained from furfurylamine and iminoesters, while amidines were prepared from the condensation of primary amines on previous imidates. Evaluation of the antioxidant activity of these compounds gave promising results.

Please read the abstract in the section 00front of this document / Dissertation (MInst Agrar (Plant Protection))--University of Pretoria, 2005. / Microbiology and Plant Pathology / unrestricted

Properties of selected types of anti-deposit and anti-graffiti polymer coatings on selected background materials are presented. It is focused on drying value, hardness and adherence of protective coatings, as well as resistance of background material, anti-deposit and anti-graffiti coatings against selected solvents. Removability of selected deposits and graffiti from anti-deposit and anti-graffiti coatings by force of solvents is also evaluated.

<p>This investigation focused on Rhoicissus tomentosa, belonging to the family, Vitaceae in an attempt to assess the phytochemistry of this plant which is widely used by traditional healers in South Africa to ensure the safe delivery during pregnancy and childbirth (Hutchings et al., 1996).</p>

<p>This investigation focused on Rhoicissus tomentosa, belonging to the family, Vitaceae in an attempt to assess the phytochemistry of this plant which is widely used by traditional healers in South Africa to ensure the safe delivery during pregnancy and childbirth (Hutchings et al., 1996).</p>

Magister Scientiae - MSc / This investigation focused on Rhoicissus tomentosa, belonging to the family, Vitaceae in an attempt to assess the phytochemistry of this plant which is widely used by traditional healers in South Africa to ensure the safe delivery during pregnancy and childbirth (Hutchings et al., 1996). / South Africa

The diplomatic and political deadlock in what has come to be known as the Palestine/Israel conflict, has led to the re-emergence of an anti-partition discourse that draws its arguments from the reality on the ground and/or from anti-Zionism. Why such a re-emergence? Actually, anti-partitionism as an antagonism depends on its corollary, partitionism, and as such, they have existed for the same period of time. Furthermore, the debate between antipartitionists and pro-partitionists – nowadays often referred to as a debate between the one-state and the two-state solution – is not peculiar to the period around 2000. It echoes the situation in the late 1910s when the British were settling in Palestine and authorising the Zionist settler colonial movement to build a Jewish homeland thus introducing the seeds of partition and arousing expressions of anti-partitionism. This dissertation aims to articulate a political history of the antipartitionist perspectives against the backdrop of an increasing acceptance of Palestine's partition as a solution. This account runs from 1915 and the first partition – that of the Arab territories of the Ottoman Empire – to 1988 and the Palestinian recognition of the principle of partition. Thus, I argue that the antipartitionist perspectives have persisted throughout history. Such a historical perspective enabled me to consider the acceptance of partition as the result of a shift from a “national and territorial liberation” strategy to the search for “sovereignty and national independence”, a shift that was operated in the Palestinian national movement as well as in the Zionist movement, and which made statehood the main objective. In this regard, the Palestinian acceptance of the principle of partition and of a two-state solution may be regarded as a legitimation of the Israeli colonial settler state.

Orientador: Wagner Vilegas / Resumo: Apesar dos diversos relatos do uso de Rhipsalis Gaërtn (Cactaceae) por populações tradicionais no tratamento de uma gama de enfermidades, há pouquíssimos estudos fitoquímicos com esse grupo de cactos e por vezes estes são superficiais, apenas indicando a possível presença de algumas classes de produtos naturais. Ademais, estudos avaliando a atividade biológica de Rhipsalis são escassos. Neste viés, este trabalho objetivou investigar a composição química do gênero Rhipsalis e avaliar possíveis atividades ligadas à sua composição, subsidiando desta forma seu uso popular. Esta dissertação foi dividida e organizada da seguinte forma: a primeira parte apresenta uma introdução geral sobre plantas medicinais e sua importância, assim como uma revisão sobre estudos fitoquímicos em Cactaceae. Em seguida, foram redigidas três seções: na primeira, investigamos a composição química de Rhipsalis teres (Vell.) Steud identificando 5 saponinas derivadas do ácido oleanólico, 2 flavonoides C-glicosilados derivados da apigenina e 2 ácidos fenólicos; na segunda, investigamos a composição química do gênero Rhipsalis identificando 28 saponinas cujo core é o ácido oleanólico e 8 flavonoides, também sugerimos fingerprints para cada espécie avaliada com base nas substâncias majoritárias, os resultados quantitativos obtidos por UPLC-MS foram eficientes na identificação das espécies com base na filogenia; na terceira, avaliamos as atividades antioxidante, antifúngica e anti-inflamatória de espécies de R... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Despite the several reports of the use of Rhipsalis Gaërtn (Cactaceae) by traditional populations in the treatment of a range of diseases, there are very few phytochemical studies with this group and sometimes these are superficial, only indicating the possible presence of some classes of natural products. In addition, there are very few studies evaluating the biological activity of Rhipsalis. Therefore, this work aimed to investigate the chemical composition of the genus Rhipsalis and to evaluate possible activities related to its composition, thus subsidizing its popular use. This dissertation was divided and organized as follows: the first part presents a general introduction on medicinal plants and their importance as well as a review on phytochemical studies in Cactaceae. Then, three sections were written: in the first one, we investigated the chemical composition of Rhipsalis teres, identifying 5 saponins derived from oleanolic acid, 2 C-glycosilated flavonoids derived from apigenin and 2 phenolic acids; in the second section, we investigate the chemical composition of the genus Rhipsalis identifying 28 saponins whose core is oleanolic acid and 8 flavonoids, we also suggested fingerprints for each species evaluated on the basis of the majority compounds, the quantitative results obtained by UPLC-MS were efficient in the identification of the species based on the phylogeny; in the third, we evaluated the antioxidant, antifungal and anti-inflammatory activities of Rhipsal... (Complete abstract click electronic access below) / Mestre

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The need for an unlimited source of islets and a safer method of immunosuppression has limited the widespread application of islet transplantation. To remedy the shortage of donor tissue, xenotransplantation of neonatal porcine islets (NPI) has been proposed. In this study we sought to determine if combining co-transplantation of NPI with Sertoli cells (SC) with a short-term monoclonal antibody (mAb) therapy would prevent NPI xenograft rejection. We hypothesize that this combination of treatments will lead to long-term NPI xenograft survival. Our result show a significant increase in the proportion of mice achieving long-term graft survival compared to untreated mice transplanted with NPI alone, as 7/7 mice treated with anti-LFA-1 mAb (p=0.001), 7/8 mice treated with anti-CD154 mAb (p=0.003), and 4/9 mice treated with anti-CD45RB mAb (p=0.020) achieved and maintained normoglycemia long-term. Therefore, we conclude that the combination of mAb therapy with SC is highly efficacious in preventing NPI xenograft rejection. / Experimental Surgery