102 research outputs found

    Synthesis and Characterisation of Cardanol Acetate and Cardanol Ether as Reactive Diluents for Alkyd Coatings

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    Alkyd resins are viscous, tacky materials that are difficult to handle. Most often, these handling problems are overcome by dissolving the resins in organic solvents, which evaporate into the atmosphere as volatile organic compound (VOC), giving rise to regulations. A reactive diluent is a compound that acts as a solvent in the liquid paint, lowering the viscosity, and chemically reacts into the final film during the curing process to give a more environmentally friendly coating and the amount of traditional solvent can be decreased. Cashew nut shell liquid (CNSL) is not currently utilized in Kenya and the objective of this work was to develop reactive diluents from chemically modified CNSL products and evaluate their compatibility with alkyd coatings. A standard reactive diluent should have low viscosity, increase drying time of less than 50 %, and be nontoxic. Cardanol was isolated using methanol and ammonia solution as the solvents in a ratio of 8:5 respectively. The percentage yield of cardanol obtained was 63.94 %. The yield of cardanol acetate obtained was 58.94 %. The cardanol acetate was also characterized by FT-IR and it showed the presence of the C=O stretch functional group characteristic of the ester and the absence of the OH group that was present in cardanol. The cardanol acetate synthesised showed a low viscosity (45 Cps) and a reduced drying time of about 25–35% compared to conventionally prepared formulations. Keywords: Cashew nut shell liquid, Cardanol, Reactive diluent, Cardanol acetate

    Use of the nested polymerase chain reaction for detection of Toxoplasma gondii in slaughterhouse workers in Thika District, Kenya

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    Background. The widely used methods of diagnosis of Toxoplasma gondii are serological. Current reports indicate a high seroprevalence of T. gondii in humans in Kenya. There is a need for more sensitive diagnostic tests, especially when the specific antibody titres are below detectable threshold levels. Use of the polymerase chain reaction (PCR) targeting the repetitive 529 base pair loci has been reported to be sensitive and specific.Objective. To detect T. gondii in a high-risk group of public health workers in Thika District, Kenya.Methods. In total, 87 human blood samples were collected from male slaughterhouse workers between 1 March 2013 and 25 June 2013. The DNA extracted was amplified by the nested PCR.Results. T. gondii was detected in 39.1% (34/87) of the workers. In the cow-sheep-goat slaughterhouses the prevalence ranged between 20% and 60%, while all the chicken slaughterhouse workers (6/6, 100%) tested positive. The difference in T. gondii positivity between the workers in the chicken slaughterhouse and those in the cattle-sheep-goat slaughterhouses was statistically significant (p=0.003).Conclusion. This study shows the presence of T. gondii in an asymptomatic high-risk group in Thika District, indicating the need for enhancement of public health awareness

    Use of the nested polymerase chain reaction for detection of Toxoplasma gondii in slaughterhouse workers in Thika District, Kenya

    Get PDF
    Background. The widely used methods of diagnosis of Toxoplasma gondii are serological. Current reports indicate a high seroprevalence of T. gondii in humans in Kenya. There is a need for more sensitive diagnostic tests, especially when the specific antibody titres are below detectable threshold levels. Use of the polymerase chain reaction (PCR) targeting the repetitive 529 base pair loci has been reported to be sensitive and specific.Objective. To detect T. gondii in a high-risk group of public health workers in Thika District, Kenya.Methods. In total, 87 human blood samples were collected from male slaughterhouse workers between  1 March 2013 and  25 June 2013. The DNA extracted was amplified by the nested PCR.Results. T. gondii was detected in 39.1% (34/87) of the workers. In the cow-sheep-goat slaughterhouses the prevalence ranged between 20% and 60%, while all the chicken slaughterhouse workers (6/6, 100%) tested positive. The difference in T. gondii positivity between the workers in the chicken slaughterhouse and those in the cattle-sheep-goat slaughterhouses was statistically significant (p=0.003).Conclusion. This study shows the presence of T. gondiiin an asymptomatic high-risk group in Thika District, indicating the need for enhancement of public health awareness.

    The Sensitivity and Specificity of Loop-Mediated Isothermal Amplification (LAMP) Assay for Tuberculosis Diagnosis in Adults with Chronic Cough in Malawi.

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    BACKGROUND: Current tuberculosis diagnostics lack sensitivity, and are expensive. Highly accurate, rapid and cheaper diagnostic tests are required for point of care use in low resource settings with high HIV prevalence. OBJECTIVE: To investigate the sensitivity and specificity, and cost of loop-mediated isothermal amplification (LAMP) assay for tuberculosis diagnosis in adults with chronic cough compared to XpertÂź MTB/RIF, fluorescence smear microscopy. METHODS: Between October 2013 and March 2014, consecutive adults at a primary care clinic were screened for cough, offered HIV testing and assessed for tuberculosis using LAMP, XpertÂź MTB/RIF and fluorescence smear microscopy. Sensitivity and specificity (with culture as reference standard), and costs were estimated. RESULTS: Of 273 adults recruited, 44.3% (121/273) were HIV-positive and 19.4% (53/273) had bacteriogically confirmed tuberculosis. The sensitivity of LAMP compared to culture was 65.0% (95% CI: 48.3% to 79.4%) with 100% (95% CI: 98.0% to 100%) specificity. The sensitivity of XpertÂź MTB/RIF (77.5%, 95% CI: 61.5% to 89.2%) was similar to that of LAMP, p = 0.132. The sensitivity of concentrated fluorescence smear microscopy with routine double reading (87.5%, 95% CI: 73.2% to 95.8%) was higher than that of LAMP, p = 0.020. All three tests had high specificity. The lowest cost per test of LAMP was at batch size of 14 samples (US9.98);thiswaslowerthanXpertÂźMTB/RIF(US 9.98); this was lower than XpertÂź MTB/RIF (US 13.38) but higher than fluorescence smear microscopy (US$ 0.65). CONCLUSION: The sensitivity of LAMP was similar to XpertÂź MTB/RIF but lower than fluorescence smear microscopy; all three tests had high specificity. These findings support the Malawi policy that recommends a combination of fluorescence smear microscopy and XpertÂź MTB/RIF prioritised for people living with HIV, already found to be smear-negative, or being considered for retreatment of tuberculosis

    Post-imperialism, postcolonialism and beyond: towards a periodisation of cultural discourse about colonial legacies

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    Taking German history and culture as a starting point, this essay suggests a historical approach to reconceptualising different forms of literary engagement with colonial discourse, colonial legacies and (post-) colonial memory in the context of Comparative Postcolonial Studies. The deliberate blending of a historical, a conceptual and a political understanding of the ‘postcolonial’ in postcolonial scholarship raises problems of periodisation and historical terminology when, for example, anti-colonial discourse from the colonial period or colonialist discourse in Weimar Germany are labelled ‘postcolonial’. The colonial revisionism of Germany’s interwar period is more usefully classed as post-imperial, as are particular strands of retrospective engagement with colonial history and legacy in British, French and other European literatures and cultures after 1945. At the same time, some recent developments in Francophone, Anglophone and German literature, e.g. Afropolitan writing, move beyond defining features of postcolonial discourse and raise the question of the post-postcolonial

    Bye-bye Barack: dislocating afropolitanism, spectral marxism and dialectical disillusionment in two Obama-era novels

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    In contextually specific and formally distinctive ways, Chimamanda Ngozi Adichie’s Americanah and Imbolo Mbue’s Behold the Dreamers are fictional interrogations of Obama’s presidential pledge to resuscitate the American dream on the wake of the global financial crash. This paper explores how they supplement and challenge familiar tropes associated with African and American, rather than African-American, diaspora writing. Given broader debates within transnational literary studies about flows and exchanges (of people, finance, cultural production, dissemination, consumption et al.) linking the global South and North, I consider how these texts grapple with the complexities and complicities of contemporary neoliberalism through the lens of renascent African Marxisms. While my chosen writers could not be described as Marxist, I engage with more materially oriented scholarship, such as Krishnan’s Writing Spatiality in West Africa and Ngugi’s The Rise of the African Novel, to consider how Americanah and Behold the Dreamers circulate in a global literary marketplace where certain texts, not to mention authors, are seen as symptomatic of an African and/or Afropolitan and/or ‘Africapitalist’ renaissance. By grappling with Marxist-inflected scholarship, this paper interrogates the politics, as well as poetics, of the oft-conspicuous airbrushing of those socio-economic, specifically class concerns at the heart of these entangled debates

    Editors’ Introduction: An Overview of the Educational Administration and Leadership Curriculum: Traditions of Islamic Educational Administration and Leadership in Higher Education

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    This chapter provides an overview of several topics relevant to constructing an approach to teaching educational administration and leadership in Muslim countries. First, it places the topic in the context of the changing nature and critiques of the field that argue for a greater internationalisation to both resist some of the negative aspects of globalisation and to represent countries’ traditions in the professional curriculum. Then, it identifies literature that presents the underlying principles and values of Islamic education that guide curriculum and pedagogy and shape its administration and leadership including the Qur’an and Sunnah and the classical educational literature which focuses on aims, values and goals of education as well as character development upon which a ‘good’ society is built. This is followed by a section on the Islamic administration and leadership traditions that are relevant to education, including the values of educational organisations and how they should be administered, identifying literature on the distinctive Islamic traditions of leadership and administrator education and training as it applies to education from the establishment of Islam and early classical scholars and senior administrators in the medieval period who laid a strong foundation for a highly sophisticated preparation and practice of administration in philosophical writings and the Mirrors of Princes writings, and subsequent authors who have built upon it up to the contemporary period. The final section provides an overview of the chapters in this collection

    Diversities, affinities and diasporas: a southern lens and methodology for understanding multilingualisms

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    We frame multilingualisms through a growing interest in a linguistics and sociology of the ‘south’ and acknowledge earlier contributions of linguists in Africa, the AmĂ©ricas and Asia who have engaged with human mobility, linguistic contact and consequential ecologies that alter over time and space. Recently, conversations of multilingualism have drifted in two directions. Southern conversations have become intertwined with ‘decolonial theory’, and with ‘southern’ theory, thinking and epistemologies. In these, ‘southern’ is regarded as a metaphor for marginality, coloniality and entanglements of the geopolitical north and south. Northern debates that receive traction appear to focus on recent ‘re-awakenings’ in Europe and North America that mis-remember southern experiences of linguistic diversity. We provide a contextual backdrop for articles in this issue that illustrate intelligences of multilingualisms and the linguistic citizenship of southern people. In these, southern multilingualisms are revealed as phenomena, rather than as a phenomenon defined usually in English. The intention is to suggest a third direction of mutual advantage in rethinking the social imaginary in relation to communality, entanglements and interconnectivities of both South and North
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