Structural and Aerodynamic Design, Procedure and Analysis of a Small V-shaped Vertical Axis Wind Turbine

Over the last two decades there has been a renewed interest in Vertical Axis Wind Turbines. This turbine configuration though unpopular for large-scale generation has found a niche market in the way of offshore energy harvesting. However, offshore wind has its challenges. In this thesis a detailed comprehensive study of a proposed V-shaped vertical axis turbine rotor is performed in order to examine its structural and aerodynamic characteristics. The design met and exceeded the safety parameters establish for test bed operation, showing a factor of safety of 1.87 with regard to fatigue stress response. A satisfactory fatigue stress design life was also achieved. Both experimental and numerical aerodynamic data have relatively good agreement achieving an overall maximum power coefficient of 0.2589 numerically and 0.251 experimentally

Establishment and evaluation of a loop-mediated isothermal assay (LAMP) for the semi-quantitative detection of HIV-1 group M virus in blood and plasma

The past decade has witnessed a dramatic increase of anti-retroviral treatment of Human Immunodeficiency Virus (HIV) infected patients in many African countries. Due to costs and sophistication of currently available commercial viral load assays, little attention has been paid to therapy monitoring through measurement of plasma viral load, a challenge that could reverse achievements already made against HIV/AIDS infection. Loop-mediated isothermal amplification (LAMP) has been shown to be simple, rapid and cost-effective, characteristics which make this assay ideal for viral load monitoring in resource limited settings. The aim of this study was to establish and evaluate LAMP for quantitative detection of HIV-1 group M virus in blood and plasma. Cell culture supernatants of HIV-1 subtype B (IIIB and MVP899-87) viruses were used to optimize reaction conditions and to test primer suitability. Together with HIV-1 M non-B subtypes, HIV-1 group O and HIV-2, the cell culture supernatants were used to evaluate the performance of LAMP, to generate a model for viral load estimation and to establish the limits of the assay. A panel of 467 clinical samples was analyzed (282 plasmas and 121 dry blood spots from Kenya and 112 plasmas from Germany) and the results obtained by LAMP were compared to those generated by the Abbott Real Time HIV-1 assay, an established commercial viral load quantification test. A linear regression equation was generated from time to detection values and used to estimate the viral loads of the samples by the LAMP assay. Kenyan samples were tested in Nairobi and Munich. LAMP primers targeting the integrase of the pol gene were found to be the most suitable compared to further 3 primer sets tested. Lower limit of detection (LLOD) of 1,200 copies/mL and lower limit of quantification (LLOQ) of 9,800 copies/mL were determined as suitable thresholds for quantitative estimations of the LAMP viral loads. Sensitivities of 82 and 86% (Kenyan samples) and 93% (German samples) and specificities of 99 and 100% were realized with plasma samples. The study also realized a sensitivity of 76% and specificity of 77% with dry blood spot samples from Kenya. In conclusion, LAMP assay shows obvious potential for diagnostic application in semi-quantification of HIV-1 group M viral load in resource limited countries. However there is a need for further improvement of primers in respect to detection of HIV-1 non-B viruses and evaluation of dry blood spot samples to ensure that more reliable results are obtained

From Alterity To Agency: Pathways Of Subversion And Resistance In Ngugi Wa Thiong’o’s Personal Essays

In this paper, we have evaluated the contribution of aesthetic and rhetorical devices to Ngugi wa Thiong’o’s artistic mission of sabotaging the political, social, cultural and economic hegemony of empire. We have focused on his deployment of anecdotes, extended metaphors, essayistic allusions, argumentative structure, persuasive juxtaposition, concession structure and irony as aesthetic categories to undermine the domineering imperial codes. Our guiding theoretical lights have been postcolonialism, stylistics and the theory of the personal essay. The postcolonial approach adopted here is in the mould of Gayatri Spivak and Kwame Anthony Appiah; the stylistics perspective is illuminated by Rodger Webster, Peter Barry, Paul Simpson, Eriko Bollobas, Michael Kirkhood Halliday and Chris Holcomb; while the theory of the personal essay is framed by Michel de Montaigne, Phillip Lopate, Theodor Adorno, Holman Clarence Hugh, John D. Ramage and Bensel-Meyers and others. This investigation is pitched in the premise that Ngugi writes subversively from the subordinated margins of ‘alterity’ against the hierarchical power of colonial and imperial empire. In this study, we selected personal essays from the following collections: Writers in Politics: Essays; Moving the Centre: The Struggle for Cultural Freedoms; Decolonising the Mind: Politics of Language in African Literature; Homecoming: Essays on African and Caribbean Literature, Culture and Politics; Penpoints, Gunpoints and Dreams: The Performance of Literature and Power in Postcolonial Africa; Something Torn and New: An African Renaissance (first published as Remembering Africa); and Secure the Base: Making Africa Visible in the Globe

Evaluation of an Antigen-Antibody “Combination” Enzyme Linked Immunosorbent Assay for Diagnosis of Hepatitis C Virus Infections

Background: Development of “combination” assays detecting in parallel, within a single test, Hepatitis C Virus (HCV) antigens and antibodies, not only reduces the window period in HCV-infection but also costs. Reduction of costs is important for developing countries where money and personal resources are limited.Methods: We compared the Monolisa® HCV Antigen-Antibody Ultra (Bio-Rad Laboratories Limited, Marnes La Coquette, France) with the AXSYM HCV version 3.0 (Abbot Diagnostics, Germany)-the latter assay detecting only antibodies to HCV. Seventy three HCV-PCR positive and negative samples were tested.Results: Although the two assays showed comparable results, two samples from a bone marrow transplant (BMT) patient of viral loads 7.8 x 105 and 8.9 x 106 IU/mL could not be detected by the Monolisa® HCV Antigen-Antibody Ultra assay. Failure to detect the two samples with viral loads considered above threshold of detection for antigen proteins suggested a lack of sensitivity by this assay to discover viral capsid protein in patient samples. Genotyping of these samples revealed genotype 1b, a HCV-subtype which is widespread and should thus be easily detected.Conclusion: We conclude that although this assay depicts high sensitivity and specificity in detecting antibodies to HCV, it seems not to add further benefit in our study population to detect HCV infections by enhanced sensitivity due the potential contingency to trace viral capsid antigens.Keywords: Ag-Ab Combination assay, Hepatitis C Virus, ELISA, Monolisa HCV Ag-Ab Ultr

Laboratory surveillance of cholera in Nyanza province during the outbreak from April to July 2007

Cholera continues to be an important cause of morbidity and mortality in many areas of the world, and there is currently a high frequency of new outbreaks in Africa. Following a confirmed cholera outbreak in Siaya, Kisumu, Bondo and Nyando districts, Nyanza province in western Kenya between April and July 2007, a laboratory surveillance study was conducted at the New Nyanza Provincial General Hospital’s Microbiology Laboratory. The study aimed at isolating and identifying the strain of Vibrio cholerae, Identifying the mean age of the patients and monitoring the susceptibility patterns to major antibiotics. It further aimed at determining effectiveness of empiric management of cholera. A total of 219 samples were processed out of which a total of 85 samples (39%) were found positive for Vibrio cholerae 01 sero‐type Inaba. The mean age recorded was 19 years (1 ≤ 80). The modal ages recorded were 8, 20 and 25. 55% (47) of the recorded cases were females while 45% (38) were males. Generally, V.Cholerae 01 sero‐type Inaba showed antibiotic resistance to trimethoprim‐sulfamethoxazole, nalidixic acid, sulfasoxazole, streptomycin and furazolidone. Tetracycline a commonly used antibiotic for empiric management was 100% effective on all isolates and remains the drug of choice. Samples obtained for case‐control study did not yield any cholera isolate. No prior exposure to any antibiotic was recorded among all the subjects. The study confirmed the effectiveness of empirical therapy on cholera and further identified the need of proper hygiene, water treatment, proper waste management and proper eating habits as means of controlling morbidity and mortality of cholera.Key words: Cholera, morbidity, mortality, empiric management, antibiotic resistanc

Prevalence of hepatitis A virus in patients attending a referral hospital in Bubanza Province, Northwest Burundi

Background: Viral hepatitis is a public health problem wide world. Hepatitis A, transmitted by fecal-oral route, is an infectious viral disease caused by hepatitis A virus and mainly due to poor sanitation. This study aimed to determine the prevalence of hepatitis A virus and associated factors in patients attending Mpanda referral hospital in Northwest Burundi.Methods: A cross-sectional study was done from November 2017 to January 2018 on 385 participants aged 2 years and above. Participants were recruited using a systematic random sampling technique. Data were collected using questionnaire from consented/assented participants. Five millilitres of venous blood was collected and analyzed. Anti-hepatitis A virus antibodies were screened using Enzyme Immuno Assay. Data were analyzed using Statistical Package for the Social Sciences version 16.0 software. A descriptive analysis was followed by bivariate analysis using a Chi-square test for comparison of various sub-groups with 5% statistical significance level. Odds ratio and 95% Confidence Intervals were calculated and presented.Results: The median age of the participants was 23 years and the range 72 years. The overall prevalence of Hepatitis A virus was 60.3%. There was a significant association between age [OR=7.22 (4.04-12.93), P <0.001], lack of clean water [OR=10.07 (5.63-18.01), P <0.001], traditional latrines [OR=1.86 (1.02-3.40), P=0.04] and Hepatitis A Virus seroprevalence.Conclusions: Present study shows high prevalence of HAV infection in patients attending Mpanda Referral Hospital. Younger age, lack of clean water and traditional latrines play roles in increasing prevalence of HAV infection in both rural and urban areas

Nurturing Global Citizens Through Teaching Literature

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Device Simulation of Sb2S3 Solar Cells by SCAPS-1D Software

Antimony sulphide (Sb2S3) has drawn research interest due to its promising properties for photovoltaic applications. The progress in developing highly efficient Sb2S3 solar cells has stimulated this study to a great extent. In this paper, we present the results of a simulation of solar cell processing parameters on the performance of the solar cell through theoretical analysis and device simulation using SCAPS software. The results of this simulation show that the solar cell performance can be enhanced to a great extent by adjusting the thickness, doping concentration and defect density of both the TiO2 buffer layer and Sb2S3 absorber layer and also the electron affinity of the TiO2 buffer layer. Optimized parameters were found to be: doping concentration of (1.0 X 1017CM3 for TiO2 and 3.0 X 1016 CM3 for Sb2S3), defect density of the Sb2S3 absorber at (1.0 X 1015.....3) and the electron affinity of the buffer layer at (4.26 eV). The results obtained were as follows: Voc of 750 mV, Jsc of 15.23 mA/cm2, FF of 73.55% and efficiency of 8.41%. These results show that Sb2S3 is a potential earth-abundant compound that can yield highly efficient solar cells

Prevalence and Genetic Characterization of Rotavirus Infections Among Children Under Five Years in Mutaho Health District, Gitega Province and Bujumbura Municipality, Burundi

Rotavirus is the leading cause of severe diarrhea in children under five years worldwide. It is ranked as a priority for vaccine. In Burundi, vaccine against rotavirus was implemented in 2013. The impact of recent rotavirus vaccination on morbidities in Burundi is not well established. Moreover, no study has been carried out to document the genetic diversity of rotavirus strains circulating in Burundi. This cross-sectional health facility-based study aimed at determining the prevalence and molecular characteristics of rotavirus infections among children under five years of age in Mutaho Health District and the Municipality of Bujumbura, in Burundi. Stool specimens were collected from children presenting with acute diarrhea. These specimens were tested for rotavirus antigen using Diagnostar® rapid test kit.  Positive stool samples were confirmed at the Kenya Medical Research Institute (KEMRI) by ELISA. Positive confirmed samples underwent RT-PCR, G and P genotyping by multiplex semi-nested PCR using a cocktail of type specific primers or by sequencing. A total of 646 participants were enrolled in this study. The overall prevalence of rotavirus was 6.2% (40/646) with 4.0% (16/400) in Mutaho health district and 9.7% (24/246) in the Municipality of Bujumbura. Rotavirus detection rate tended to increase as the level of precipitation went down, showing a significant negative association between the two variables. (OR = 15.2; P = 0.0001). In addition, rotavirus detection rate was higher in Bujumbura Municipality than in Mutaho health district (OR = 2.6; P = 0.005). Two G genotypes were identified, G1 the predominating G genotype accounted for 53.8% (14/26) followed by G12 (46.2%, 12/26). The prevalence of the genotype G1 of Group A rotavirus was significantly higher in Bujumbura Municipality than in Mutaho health district while G12 predominated in Mutaho health district (OR = 7.33; P = 0.026). Rotavirus strains from pigs might have contributed to the high prevalence of human G12 rotavirus in that area. Three different P types were identified P[8] the most common, followed by P[6] and P[4]. The most common G/P combination genotype was G1P[8] which accounted for 45.5% of all rotavirus genotypes identified, followed by G12 P [8] (41.0%), G1P [6] (4.5%), G12 P [6] (4.5%) and G12 P [4] (4.5%). The emergence of G12 rotavirus strains which share neither G nor P genotypes with currently used rotavirus vaccines raises public health concerns as they have the potential to challenge their efficacy. Therefore, we recommend to initiate and maintain a continuous rotavirus strain surveillance in Burundi so as to monitor trends in the occurrence of these prevailing and potentially emerging new strains. Keywords: Rotavirus, diarrhea, genetic diversity, prevalence, Mutaho, Bujumbura, children DOI: 10.7176/JBAH/9-10-04 Publication date:May 31st 201