Treatment Effects and Integrated Morbidity Control of Schistosomiasis

Schistosomiasis is caused by the blood fl uke and leads to signifi cant ill-health and economic burden. The disease is common in the tropics and subtropics and acquired through contact with freshwater bodies infested with the infective cercariae shed from the intermediate host snail. From a public health perspective, the three most important species are Schistosoma mansoni and S. japonicum (causing intestinal schistosomiasis) and S. haematobium (causing urinary schistosomiasis). Schistosomiasis is endemic in 76 countries and territories worldwide (Engels et al. 2002; Steinmann et al. 2006) with around 85% of the infections confi ned to sub- Saharan Africa (Savioli et al. 1997; Chitsulo et al. 2000). Schistosomiasis is largely confi ned to rural dwellings and exacerbates poverty (Hotez et al. 2008; Wang et al. 2008). In some areas of sub-Saharan Africa there is an overlap in distribution of S. mansoni and S. haematobium resulting in mixed infections (WHO 2002). This thesis focuses on urinary schistosomiasis due to S. haematobium and intestinal schistosomiasis due to S. mansoni. Schistosomiasis is largely related to poverty, and efforts to alleviate poverty through development of water-related projects tend to increase transmission of the infection (Poda et al. 2004; Steinmann et al. 2006). Mostly children, women and farmers in poor rural areas who depend on water contact for recreational, domestic or occupational activities are affected. Peri-urban schistosomiasis is on the increase (Kloetzel et al. 1994; Chimbari & Chirundu 2003; Njiokou et al. 2004), and movement of displaced people from confl ict zones has contributed to the spread of the disease to previously non-endemic areas (Chitsulo et al. 2000)

A multi-level refinement approach towards the classification of quotidian activities using accelerometer data

Wearable inertial measurement units incorporating accelerometers and gyroscopes are increasingly used for activity analysis and recognition. In this paper an activity classification algorithm is presented which includes a novel multi-step refinement with the aim of improving the classification accuracy of traditional approaches. To do so, after the classification takes place, information is extracted from the confusion matrix to focus the computational efforts on those activities with worse classification performance. It is argued that activities differ diversely from each other, therefore a specific set of features may be informative to classify a specific set of activities, but such informativeness should not necessarily be extended to a different activity set. This approach has shown promising results, achieving important classification accuracy improvements of up to 4% with the use of low-dimensional feature vectors

Pesticidal Effects of Extracts from Hyptis suaveolens and Hyptis spicigera on Cowpea Weevils

This experimental research was conducted with the view of determining the effectiveness of Hyptis suaveolens and Hyptis spicigera extracts on cowpea seeds in deterring the feeding habit and life span of cowpea weevils. Masses of 400 and 500 grammes of pulverized samples of the two plants, Hyptis suaveolens and Hyptis spicigera were separately extracted by percolation with 2200 millilitres of 95% ethanol respectively. The percolates were evaporated to dryness at room temperature to give crude extracts of both plants which were each subjected to a partition process. Soluble solvent extracts of the two plants were applied on cowpea seeds and subjected to cowpea weevils by two-choice feeding deterrent method. The chloroform soluble extracts were found to be most active extracts of both plants with the least percentage consumption indices and higher percentage mortalities. This was a clear indication that these chloroform soluble extracts contained most of the toxic component(s) of the plants which can be used to protect cowpea seeds to some period of time. The study tasks the Ministry of Food and Agriculture to consider providing funding and further research into the use of the pesticides from these plant extracts to maintain the buoyancy of biodiversity as well as the environment in Ghana

Is diversity good?

Prominent ethical and policy issues such as affirmative action and female enrollment in science and engineering revolve around the idea that diversity is good. However, even though diversity is an ambiguous concept, a precise definition is seldom provided. We show that diversity may be construed as a factual description, a craving for symmetry, an intrinsic good, an instrumental good, a symptom, or a side effect. These acceptions differ vastly in their nature and properties. The first one cannot lead to any action and the second one is mistaken. Diversity as intrinsic good is a mere opinion, which cannot be concretely applied; moreover, the most commonly invoked forms of diversity (sexual and racial) are not intrinsically good. On the other hand, diversity as instrumental good can be evaluated empirically and can give rise to policies, but these may be very weak. Finally, symptoms and side effects are not actually about diversity. We consider the example of female enrollment in science and engineering, interpreting the various arguments found in the literature in light of this polysemy. Keywords: ethics, policy, higher education, female students, minority students, affirmative actionComment: 7 page

Liver stiffness and virologic outcomes after introducing tenofovir as part of antiretroviral therapy in lamivudine-experienced adults with HIV and hepatitis B virus (HBV) co-infection in Ghana: four-year follow up of the prospective HEPIK cohort

Introduction Until recently lamivudine was the only available agent to treat hepatitis B in the context of HIV infection in sub‐Saharan Africa. Tenofovir is gradually becoming available although access remains far from universal. Long‐term outcomes of introducing tenofovir as part of antiretroviral therapy (ART) in subjects previously extensively exposed to lamivudine as the sole HBV‐active agent in the region are unknown. Methods We report from a prospective cohort of HIV/HBV co‐infected adults attending for HIV care in Kumasi, Ghana, where HBsAg prevalence is 14%. HBsAg‐positive subjects were invited to attend for transient elastography (TE) and blood sampling before the introduction of tenofovir (TO) as part of ART, and within 1 year (T1) and 4 years (T2) of starting tenofovir. Adherence and alcohol consumption were determined by a questionnaire‐based interview. Results Overall 178 patients underwent evaluation at T0/T1, of whom 98 (55%) also attended for assessment at T2. Remaining patients were lost to follow up (50; 28%); had died (10; 6%); declined to attend (17; 10%); or were excluded due to pregnancy (2; 1 %) or invalid TE (1; 1 %). Of the 98 subjects, 94 had started tenofovir‐based ART and had received tenofovir for median 4 years (IQR 3.8, 4.1), while continuing previous lamivudine (Table 1). By multivariable linear regression, female gender, no history of alcohol excess, and higher HBV DNA level, higher liver stiffness, and lower platelet count at T0/T1 were significant predictors of decreasing liver stiffness between TO/1 and T2. No treatment‐emergent resistance mutations in HBV polymerase were observed by Sanger sequencing among subjects with HBV DNA>100 lU/ml at T2; one subject showed M204V+V173L+L180M at both TO and T2. Conclusions This is the first report of the long‐term impact on liver stiffness and virologic parameters of introducing tenofovir as part of ART in extensively lamivudine exposed HIV/HBV co‐infected patients in sub‐Saharan Africa. Significant reductions in liver stiffness and improved HBV control were observed at four years

The everyday experience of xenophobia: performing The Crossing from Zimbabwe to South Africa

Debates on the underlying causes of xenophobia in South Africa have proliferated since the attacks -between March and May 2008. Our article shows how exploring the everyday 'ordinariness' of xenophobia as performance can contribute additional insights not readily available in the public media or in works such as the recently published Go home or die here.- violence, xenophobia and the reinvention of difference (Hassim et al. 2009). The claim that as metaphor the meaning of performance is discovered in the dialectic established between the fictitious and actual context, provides a point of departure for a discussion of an autobiographical one-man play, The Crossing, in which Jonathan Nkala performs .his hazardous and 'illegal' rites of passage from Zimbabwe to South Africa. The play's aesthetic of 'witnessing', associated with the protest generation, intersects with and looks beyond a post-Truth and Reconciliation Commission (TRC) aesthetic. To contextualise our discussion of Nkala's work we track trends in responses to xenophobia, including the suggestion that the attacks were underpinned by prevailing discourses of exceptianaJism and indigeneity. However, the intimacy of targeting those living close to you needs fuller anatysis. We will argue that the liminality of the performance event provides scope for making connections not directly 'there' at the moment of performance. This has a bearing on the 'return' to Fanon and claims about 'negrophobia' characterising many reports in the public domain on the events of 2008. In turn, this invites speculation about the re-alignments indicated here.DHE

Eureka and beyond: mining's impact on African urbanisation

This collection brings separate literatures on mining and urbanisation together at a time when both artisanal and large-scale mining are expanding in many African economies. While much has been written about contestation over land and mineral rights, the impact of mining on settlement, notably its catalytic and fluctuating effects on migration and urban growth, has been largely ignored. African nation-states’ urbanisation trends have shown considerable variation over the past half century. The current surge in ‘new’ mining countries and the slow-down in ‘old’ mining countries are generating some remarkable settlement patterns and welfare outcomes. Presently, the African continent is a laboratory of national mining experiences. This special issue on African mining and urbanisation encompasses a wide cross-section of country case studies: beginning with the historical experiences of mining in Southern Africa (South Africa, Zambia, Zimbabwe), followed by more recent mineralizing trends in comparatively new mineral-producing countries (Tanzania) and an established West African gold producer (Ghana), before turning to the influence of conflict minerals (Angola, the Democratic Republic of Congo and Sierra Leone)

New approaches to measuring anthelminthic drug efficacy: parasitological responses of childhood schistosome infections to treatment with praziquantel

By 2020, the global health community aims to control and eliminate human helminthiases, including schistosomiasis in selected African countries, principally by preventive chemotherapy (PCT) through mass drug administration (MDA) of anthelminthics. Quantitative monitoring of anthelminthic responses is crucial for promptly detecting changes in efficacy, potentially indicative of emerging drug resistance. Statistical models offer a powerful means to delineate and compare efficacy among individuals, among groups of individuals and among populations.; We illustrate a variety of statistical frameworks that offer different levels of inference by analysing data from nine previous studies on egg counts collected from African children before and after administration of praziquantel.; We quantify responses to praziquantel as egg reduction rates (ERRs), using different frameworks to estimate ERRs among population strata, as average responses, and within strata, as individual responses. We compare our model-based average ERRs to corresponding model-free estimates, using as reference the World Health Organization (WHO) 90 % threshold of optimal efficacy. We estimate distributions of individual responses and summarize the variation among these responses as the fraction of ERRs falling below the WHO threshold.; Generic models for evaluating responses to anthelminthics deepen our understanding of variation among populations, sub-populations and individuals. We discuss the future application of statistical modelling approaches for monitoring and evaluation of PCT programmes targeting human helminthiases in the context of the WHO 2020 control and elimination goals