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Banana production landscapes in the African Great Lakes Region (AGLR) have been under immense pressure from Xanthomonas wilt (XW) disease over the past two decades. XW, first reported on banana in central Uganda and eastern DR Congo in 2001, has since spread to the entire AGLR. XW is currently spreading westwards from hot spots in eastern DR Congo highlands, putting the plantain (Musa AAB genome) belt of central and west Africa at risk. In-depth understanding of the key variables responsible for disease spread, current hotspots, and vulnerable landscapes is crucial for disease early warning and management. We mapped aggregated disease distribution and hotspots in the AGLR and identified vulnerable landscapes across African banana production zones. Available data on disease prevalence collected over 11 years was regressed against environmental and expert developed covariates to develop the AGLR XW hotspots map. For the Africa-wide risk map, precipitation, distance to hotspots, degree of trade in fresh banana products, production zone interconnectedness and banana genotype composition were used as covariates. In the AGLR, XW was mainly correlated to precipitation and disease/banana management. Altitude and temperature had unexpectedly low effects, possibly due to an overriding impact of tool-mediated spread which is part of the management covariate. In the AGLR, the eastern part of DR Congo was a large hotspot with highest vulnerability. Apart from endemic zones in the AGLR and Ethiopia, northern Mozambique was perceived as a moderate risk zone mainly due to the predominance of ‘Bluggoe’ (Musa ABB type) which is highly susceptible to insect-vectored transmission. Presence of XW hotspots (e.g. eastern DR Congo) and vulnerable areas with low (e.g. north-western Tanzania) or no disease (e.g. Congo basin, western DR Congo and northern Mozambique) pressure suggest key areas where proactive measures e.g. quarantines and information sharing on XW diagnosis, epidemiology, and control could be beneficial. [ABSTRACT FROM AUTHOR]

Objective: African-Caribbean men in the United Kingdom in comparison with other ethnicities have the highest incidence rate of prostate cancer. Psychosocial aspects related to screening and presentation impact on men's behavior, with previous studies indicating a range of barriers. This study explores one such barrier, the digital rectal examination (DRE), due to its prominence within UK African-Caribbean men's accounts.Methods: African-Caribbean men with prostate cancer (n = 10) and without cancer (n = 10) were interviewed about their perceptions of DRE. A synthetic discursive approach was employed to analyze the data.Results: Findings illustrate that an interpretative repertoire of homophobia in relation to the DRE is constructed as having an impact upon African-Caribbean men's uptake of prostate cancer screening. However, the discursive focus on footing and accountability highlight deviations from this repertoire that are built up as pragmatic and orient to changing perceptions within the community.Conclusions: Health promotion interventions need to address the fear of homophobia and are best designed in collaboration with the community. [ABSTRACT FROM AUTHOR]

Soil data are largely absent for most of Africa. For landscapes with recognizable catenary elements, this data gap can be filled by mapping the catenary units and assigning them with known soil properties. An example is the landscape map for a region with dambos in central Uganda, which shows the four catenary units in order from well-drained to seasonal wetland: uplands, margins, floors, and bottoms. However, this map was created using optical data, which are cost prohibitive and are also limited by cloud cover. We evaluated the potential of freely available aerial gamma-ray spectrometry (AGRS) data as an alternative source of classification inputs. Analysis of variance based upon field data for a region with dambos in central Uganda showed gamma activity to differ along the catenary sequence, with landscape position explaining an appreciable proportion of variation of potassium (28%), thorium (27%), and uranium (46%). Using the three gamma channels, together with terrain indices derived from the Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) as inputs, three classifiers were evaluated – conditional inference trees (CITs), random forests (RF), and multinomial-iterative self-organizing data analysis (ISODATA). While untransformed terrain and gamma predictors were used for the first two methods, we applied the ISODATA classification to landscape unit probability maps generated using multinomial principal components regression. For the CIT classification, all decision rules were based on terrain data, which might explain why the map was slightly less accurate (unweighted kappa = 0.61, linear weighted kappa = 0.73) than the map created using a RF classifier (unweighted kappa = 0.63, linear weighted kappa = 0.74), where both terrain and gamma predictors were used. But the existence of artefacts of margins within uplands in the map based on CIT modelling, and not that created using RF, is because the former missed the smoothing effect of gamma, attributed to zonal differences in activity of all three gamma channels. The multinomial-ISODATA predictions were poor (unweighted kappa = 0.56, linear weighted kappa = 0.67), partly because the regression model could not adequately resolve differences between bottoms and floors. However, we did find the probability maps generated using multinomial regression to be useful end products that capture the continuous nature of landscape unit transitions. It is important to note that in this study we used 90 m grid resolution gamma and terrain data to predict features that transition over distances of less than 10 m, so better results might be possible with finer-resolution gamma and terrain data. [ABSTRACT FROM AUTHOR]

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Objective To examine associations between exposure to physical violence (PV) or sexual violence (SV) and adverse health behaviours among a sample of children in five African countries. Methods In a cross-sectional analysis of data from Namibia, Swaziland, Uganda, Zambia and Zimbabwe -- countries that participated in the Global School-based Student Health Survey in 2003 or 2004 -- we compared the relative frequency of several adverse health behaviours among children (primarily students 13--15 years of age) who did and who did not report exposure to PV or SV. We estimated odds ratios (ORs) for such behaviours and their 95% confidence intervals (CIs) after adjusting for age and sex. Findings Exposure to PV during the 12 months preceding the survey was reported by 27--50% (average: 42%) of the children studied in the five countries, and lifetime exposure to SV was reported by 9--33% (average: 23%). Moderate to strong associations were observed between exposure to PV or SV and measures of mental health, suicidal ideation, current cigarette use, current alcohol use, lifetime drug use, multiple sex partners and a history of sexually transmitted infection (P ≤ 0.05 for all associations). For example, the odds of being a current cigarette smoker were higher in children involved in one fight (OR: 2.20; 95% CI: 1.77--2.75), 2--5 fights (OR: 3.43; 95% CI: 2.54--4.63), or 6 fights or more (OR: 5.95; 95% CI: 4.37--8.11) (P for trend < 0.001) during the 12 months preceding the survey than in children unexposed to PV. Conclusion Childhood exposure to PV and SV is common among African children in some countries and is associated with multiple adverse health behaviours. In developing countries, increased awareness of the frequency of exposure to violence among children and its potential health consequences may lead to heightened attention to the need for health promotion and preventive programmes that address the problem. [ABSTRACT FROM AUTHOR]

Abstract: Constructing a cost-effective and detailed digital soil map of Africa will require the extensive utilization of both legacy soil data and legacy soil-landscape knowledge — which in Africa is primarily available from reconnaissance-scale catena or association maps and related studies. We evaluated a hybrid approach for disaggregating reconnaissance scale soil maps: rapid and inexpensive delineation of representative soil-landscape units in the field using expert knowledge, followed by the use of inductive, empirical, and correlative modeling techniques to map these landscape units. Our 2214 km2 study area, located in central Uganda, consisted predominantly of catenae that terminate in seasonal valley floor wetlands called dambos — a type of landscape that can be found throughout the African continent. For model training and validation, we identified four landscape classes in the field using published expert knowledge: well-drained uplands (red soils); sloping dambo wetland margins (gradient>2%), frequently inundated dambo bottoms (hummocky microtopography), and flat dambo floors (default). Using binary decision trees (BDT) with multispectral and topographic remote sensing covariates, we created a 20 m resolution map of these four classes. Multispectral inputs included reflectance values, vegetation indices, and spectral mixture modeling fractions from Système Pour l''Observacion de la Terre (SPOT) 4 satellite images acquired in December, 2006 and February, 2007. Topographic inputs consisted of a digital elevation model (DEM) from Shuttle Radar Topography Mission (SRTM) data, slope, and 20 relative elevation layers calculated using moving windows of various sizes. Decision rules were based upon the following input variables: the Normalized Difference Vegetation Index (NDVI), the Normalized Difference Infrared Index (NDII), the shortwave infrared (SWIR) reflectance, northing, slope, and two relative elevation layers. The overall classification accuracy of 75.5% and Kappa coefficient of 0.67 suggest that a combination of multispectral, topographic, and spatial data may be used to reliably classify landscape classes for dambo-terminated catenae. At 59% of the 2214 km2 study area, the upland class was by far the most abundant, with margins at 21%, floors at 12% and bottoms at 8%. A statistical analysis of soil property data from a small catchment located within the study area showed significant class differences in soil texture, color, organic carbon (SOC), base saturation, pH, effective cation exchange capacity (ECEC), and clay mineralogy. Though detailed soil maps are rare in Africa, reconnaissance soil maps can be inexpensively disaggregated to provide a valuable starting point for digital soil mapping. [Copyright &y& Elsevier]

This article discusses the sustainable harvest of bushmeat or wildlife species used for food in Africa. According to the authors, there is a consensus that a bushmeat crises exists from both a conservation and development perspective. They argue for a more supportive and consistent bushmeat development policy. They suggest that bushmeat harvesting is usually a survival strategy rather than a development policy. They recommend managing for all values of wildlife by creating protected areas where no hunting is allowed, production forests where hunting is managed sustainably and farm bush areas which would be managed locally where harvesting is ensured.