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Master thesis describes the design of travelling and lifting mechanism for the Bell helicopter with a minimum weight of 2,000 kg and travel of 80mm. In some parts of this work will find an overview of the manufactured equipment, analysis of possible mechanisms, the concept with strength calculations with FEM supported calculations of each frame.

There is good pharmacological evidence that cannabinoids caused cellular changes by interacting with specific cannabinoid receptors (CBR) (Klein et al., 2000). To date, two CBRs have been identified in the human body, designated Cannabinoid Receptor 1 (CB1) and Cannabinoid Receptor 2 (CB2) (Begg et al., 2005). Endogenously occurring compounds with action at the CBRs also exist and they are called endocannabinoids. One of the four known endocannabinoids is anandamide (AEA). The endocannabinoid system, present in the human body, plays a significant role in altering the physiology of the immune system. Enhancement of this system’s anti-inflammatory effect could possibly present a vital therapeutic target for central and peripheral inflammatory disorders. A number of synthetic CB1 or CB2 specific antagonists have been developed including the highly specific CB1 receptor antagonist/reverse agonist named Rimonabant/ SR141716A. SR compounds are considered unique because these compounds not only inhibit the binding and function of cannabimimetic agents, but also act as inverse agonists. Activation of CB1 receptors produces inappropriate CNS side effects including psychoactivity, dependence and sedation (Clayton et al., 2002) whereas CB1 receptor antagonists/inverse agonists avoid or prevent these side effects. Taking the above information into consideration, Rimonabant has the potential to offer an effective long term treatment of chronic inflammatory disorders without the serious side effects of commonly used treatments. The main aim of this study is to investigate the in vitro effects of Rimonabant alone and in combination with anandamide on inflammatory associated cytokine production by human umbilical vein endothelial cells (HUVEC) and macrophage cultures. After careful consideration of the evidence stating that endothelial cells produce several important molecules vital to the inflammatory response of the body and the confirmation that CB1 receptor mRNA is generally present in endothelial cells, the use of HUVEC was deemed to be satisfactory for this study. The first phase of the study was dedicated to establishing the technique to isolate HUVEC from fresh human umbilical cord within the local laboratory and to maintain these in culture for further use during experimental procedures to test the effects of CB1 ligands. The isolation procedure, trypsinising, freezing away and thawing methods used during this experiment produced healthy HUVEC in sufficient numbers for further use. The next step was to determine the maximum in vitro concentrations at which Rimonabant and anandamide had insignificant cytotoxic effect on selected human cells and in doing so, determine suitable concentrations for further experimentation. Both compounds had a dose related anti-proliferative response when tested on HUVEC. The same dose related response was observed during the Rimonabant exposure to human lymphocytes, but no decrease in lymphocyte viability was observed when treated with anandamide at the concentrations tested. It is evident from the results that there was an almost ten times difference in the IC50 value of the two different products (14.3 μM for Rimonabant and 124.2 μM for anandamide) which was statistically significant. Flow cytometry was used to determine the effects of Rimonabant and anandamide on the surface expression of the CR3 complement receptor by human neutrophils. Neither Rimonabant nor anandamide significantly affect CR3 expression on the surface of freshly isolated human neutrophils and would exclude the CR3 expression pathways as a potential mechanism of action for the anti-inflammatory effects of these compounds. The in vitro effect of Rimonabant and anandamide alone and in combination on the production of cytokines by human macrophages and by HUVEC was determined. Anandamide was shown to inhibit the production of all the detectable cytokines (IL-8, IL-1β and IL-6 in both cell types and IL-10 and TNF-α in macrophages). Furthermore this inhibitory effect was attenuated by pre-treatment Rimonabant. These results would suggest that anandamide could induce anti-inflammatory effects observed in macrophages and HUVEC, through cannabinoid receptors. Rimonabant also inhibited the production of all the detectable cytokines following treatment with 0.5 μM and 3 μM respectively. The anti-inflammatory effects of anandamide were attenuated when combined with 1 μM of Rimonabant. Throughout the various cytokine responses, the dose-response relationship appeared to follow a bell-shaped dose-response. This occurrence proposes that Rimonabant displaces anandamide and blocks the anti-inflammatory effects of the agonist. Flow cytometry was used to determine the effects of Rimonabant and anandamide alone and in combination on the extracellular surface expression of ICAM-1 by HUVEC. Neither Rimonabant nor anandamide had any significant inhibitory effect on the expression of ICAM-1 by HUVEC. Considering the low levels for ICAM-1 expressed by the HUVEC during this experiment and the literature supporting more effective methods of activating the ICAM-1 gene and subsequent up-regulation of ICAM-1 proteins, TNF-α stimulation of HUVEC might produce a different result compared to IL-1β stimulation. The final phase of the project was to determine the effects of Rimonabant and anandamide on the adhesion of human neutrophils to HUVEC. There was no significant difference with relation to the neutrophil adhesion to HUVEC following the treatment with various combination concentrations of the compounds, and also no significant effect following treatment with either test compound individually. Although a specific mechanism of action for Rimonabant could not be uncovered during this study, there is evidence that several possible mechanisms can be excluded. The results support observations made by other researchers and the hypothesis that Rimonabant has anti-inflammatory effects. The results provide motivation for further experimentation to better understand these anti-inflammatory actions of Rimonabant. / Dissertation (MSc)--University of Pretoria, 2012. / Pharmacology / unrestricted

Magister Artium - MA / Volgens die Suid-Afrikaanse grondwet het vroueregte na die eerste demokratiese verkiesing in 1994 deel ontstaan. Dié vryhede wat die vrou ontvang het, was egter nie onproblematies nie – Suid-Afrikaanse vroue word steeds uitgelewer aan ’n patriargale samelewing. Die posisie van die swart vrou is veral problematies – swart vroue word nie net gemarginaliseer gebaseer op geslag nie, maar ook steeds as gevolg van ras. Die posisie van swart vroueskrywers in die Afrikaanse letterkunde asook die Nederlandse letterkunde is dan ook ’n aspek wat nog nie genoegsaam ondersoek word nie. Vir die doeleindes van hierdie studie word die werk van twee swart digters, een van Suid- Afrikaanse herkoms (Ronelda S. Kamfer) en een van Nederland (Simone Atangana Bekono), ondersoek. In 2008 word Ronelda S. Kamfer een van die eerste swart vroueskrywers wat ’n volledige Afrikaanse digbundel by ’n hoofstroomuitgewery publiseer. Ten spyte van breë mediadekking van haar werk – wat met verskeie literêre pryse bekroon is – is daar nog betreklik min akademiese studies oor Kamfer gedoen. Simone Atangana Bekono is redelik nuut in die poësiewêreld en geen akademiese studies is nog oor haar werk onderneem nie. Dié studie is dus daarop gemik om die akademiese gapinge te vul deur ’n komparatiewe studie te doen met die aandag gefokus op die digters Ronelda Kamfer en Simone Atangana Bekono. Die swart feminisme word vernaamlik as teoretiese invalshoek gebruik gegewe die twee digters se agtergronde asook die tematiek van hul werk. Kamfer se oeuvre (Noudat slapende honde, grond/Santekraam, Hammie en Chinatown) en Bekono se debuutbundel, Hoe de eerste vonken zichtbaar waren, sal as hoofbronne in hierdie tesis dien. Tesame met die voorafgenoemde sal daar ook verskeie sekondêre bronne en artikels wat swart feminisme, postkolonialisme, die stem van die gemarginaliseerde en ook komparatisme in die letterkunde ondersoek, gebruik word. / South Africa

Tsirelson's bound is the upper bound for a Bell inequality which is valid for all quantum mechanical systems. We discuss why Tsirelson's bound was developed by looking at some historical arguments in quantum physics, such as the Einstein-Podolsky-Rosen (EPR) paradox, an argument for the quantum mechanical description of physical reality being incomplete, and local hidden variables. We present the counterargument to those theories, Bell's inequality, which later expanded to include any inequality that a local system fulfills, but that an entangled quantum system can violate. We present the proof of two specific Bell inequalities: the Clauser-Horne-Shimony-Holt (CHSH) inequality and the I3322 inequality. Then the Tsirelson's bound for the CHSH inequality is proven with a simple system of two entangled spin-1/2 particles and with a general argument that is valid for all entangled systems. We give the upper quantum bound for the generalized CHSH inequality, which describes the situation that we have more than two measurement options, by using semidefinite programming. We prove the Tsirelson's bound for the I3322 inequality by using maximally entangled systems and semidefinite programming. Finally, we discuss the upper bounds that are obtained from these different methods. / Tsirelson's gräns är den övre gränsen till en Bell olikhet som är giltig för alla kvantmekaniska system. Vi diskuterar varför Tsirelson's gräns togs fram genom att titta på histroiska argument i kvantfysik, så som Einstein-Podolsky-Rosen (EPR) paradoxen, ett argument som säger att den kvantmekaniska beskrivningen av den fysikaliska verkligheten är offulständig, och lokala gömda variabler. Vi presenterar motargumentet till dessa teorier, Bell's olikheter, som senare generaliserades för att betyda alla olikheter som lokala system uppfyller, men som ett system i kvantsammanflättning kan bryta. Vi presenterar beviset för två specifika Bell olikheter: CHSH olikheten och I3322 olikheten. Sedan bevisas Tsirelson's gräns för CHSH olikheten med ett enkelt system av två sammanflättade spin-1/2 partiklar och ett generellt argument som stämmer för alla sammanflättade system. Vi ger den övre kvant gränsen för den generaliserade Clauser-Horne-Shimony-Holt (CHSH) olikheten, som beskriver situationen då vi har flera valmöjligheter för mätningar, genom att använda semidefinit programmering. Vi bevisar Tsirelson's gräns för I3322 olikheten genom att använda maximalt sammanflättade system och semidefinit programmering. Till slut diskuterar vi de övre gränserna som har erhållits ifrån de olika metoderna.

This essay analyzes Esther Greenwood’s identity crisis, mental illness, and recovery in Sylvia Plath’s novel The Bell Jar (1963) from a feminist psychoanalytic perspective. The purpose is to understand the cultural and psychological mechanisms behind the main character’s situation. Esther is a talented and hardworking student who dreams of a literary career in 1950’s America. At the age of nineteen, events and realizations launch Esther into an identity crisis that leads to severe depression. Why she falls ill, and the nature of her illness and recovery, are up for interpretation. The thesis of this essay is that Esther Greenwood’s identity crisis, mental illness, and recovery can be explained using a feminist interpretation of Freud’s theories of hysteria and melancholia, and the development of the differences between the sexes, which includes the Freudian concepts of castration, bisexuality, and the Oedipus complex.

For decades now, the Appalachian community has been internally combatting two equally strong feelings—an inherently rich love of the mountains and a conflicting urge to leave the mountains. In recent years, Appalachian writers have produced a new literary tradition of identifying, discussing, and remedying this dilemma. Jim Wayne Miller’s 1997 The Brier Poems unapologetically explores the Appalachian community’s complicated relationship to its region. bell hooks’ 2012 Appalachian Elegy: Poetry and Place and Savannah Sipple’s 2019 WWJD and Other Poems then expand Miller’s exploration as both hooks and Sipple collectively represent voices that have often been left out of the stereotypical Appalachian narrative; their literature widens the lens of Appalachian experience and repositions the importance of the Appalachian canon. hooks and Sipple are contemporaries in conversation with Miller as all three authors have declared the Appalachian experience to have never been hegemonic—reclaiming, embracing, and uniting a modern Appalachian identity.

It is well known that Universal cycles (U-cycles) of k-letter words on an n-letter alphabet exist for all k and n. In this paper, we prove that Universal cycles exist for several restricted classes of words, including non-bijections, "equitable" words (under suitable restrictions), ranked permutations, and "passwords". In each case, proving the connectedness of the underlying de Bruijn digraph is a non-trivial step.

This essay analyses the life of Joyce, the protagonist in “Somewhere in England”, the fourth section of Crossing the River by Caryl Phillips, using an intersectional feminist perspective. It attempts to show how patriarchy, classism, and racism intersect to shape Joyce’s life and to limit her possibilities. The essay argues that at the beginning, Joyce is too naïve to fully understand the power structures prevailing in her society, and therefore, she is different from those around her. However, she successively experiences not only patriarchal oppression but also class and race oppressions. The result is that Joyce accepts her social position when she understands that it is difficult for an individual woman to challenge the intersected multiple oppressions of the capitalist, supremacist, patriarchal society.

Notre thèse de maîtrise en histoire de la philosophie s’intéresse au débat esthétique, sociologique, politique et philosophique qu’a suscité l’apparition de la notion de « postmoderne ». Plus précisément, nous nous penchons sur l’intervention marxiste anglo-américaine dans ce débat au cours des années 1980 à travers l’examen de trois auteurs — Marshall Berman, Fredric Jameson et David Harvey — qui y ont contribué de manière significative. Afin de lever le voile de la confusion quant aux diverses significations attachées au champ lexical de « postmoderne », nous aurons recours au concept heuristique de la « question postmoderne » qui permet de distinguer trois niveaux de signification — culturel-esthétique, théorie du changement social, philosophico-historique —, mais aussi de les rassembler et de discuter du « postmoderne » dans sa généralité. La réponse marxiste à la question postmoderne fut hautement dépendante des interventions de Daniel Bell et Jean-François Lyotard et leur présence dans ce travail permettra de comprendre le contexte intellectuel et conceptuel avec, notamment, la nature de la transition entre le modernisme et le postmodernisme esthétiques, l’émergence d’une société postindustrielle et l’idée d’une postmodernité comme crise de légitimation des métarécits de la modernité. Nous examinons de quelle manière Berman, Jameson et Harvey ont traité de la question postmoderne dans leurs écrits s’étendant du début des années 1980 à la fin de cette décennie. L’on pourra voir que ce marxisme anglo-américain ne s’oppose pas de prime abord aux notions de « postmodernisme » ou de « postmodernité », bien qu’il craigne les illusions idéologiques qui accompagnent ces notions et tendent à obscurcir le rôle joué par le capitalisme dans les transformations sociales et culturelles.