Towards Semantic Integration of Heterogeneous Sensor Data with Indigenous Knowledge for Drought Forecasting

In the Internet of Things (IoT) domain, various heterogeneous ubiquitous devices would be able to connect and communicate with each other seamlessly, irrespective of the domain. Semantic representation of data through detailed standardized annotation has shown to improve the integration of the interconnected heterogeneous devices. However, the semantic representation of these heterogeneous data sources for environmental monitoring systems is not yet well supported. To achieve the maximum benefits of IoT for drought forecasting, a dedicated semantic middleware solution is required. This research proposes a middleware that semantically represents and integrates heterogeneous data sources with indigenous knowledge based on a unified ontology for an accurate IoT-based drought early warning system (DEWS).Comment: 5 pages, 3 figures, In Proceedings of the Doctoral Symposium of the 16th International Middleware Conference (Middleware Doct Symposium 2015), Ivan Beschastnikh and Wouter Joosen (Eds.). ACM, New York, NY, US

Effect of manure quality on nitrate leaching and groundwater pollution in wetland soil under field tomato (Lycopersicon esculentum, Mill var. Heinz) rape (Brassica napus, L var. Giant)

Recent decades have seen an increase in groundwater pollution thought to be a consequence of increasing intensity of land use, primarily through greater use of high N analysis materials as fertilizers. A two-season lysimeter experiment was carried out in a wetland in central Zimbabwe in order to determine the effect of cattle manure quality on (1) NO3–N concentration in leachate and nitrate leaching (2) dry matter accumulation and uptake of N by tomato and rape crops grown in wetland conditions. Two cattle manure quality types based on N content were used in the experiment. The manure collected from a kraal of the smallholder wetland community was classified as high quality manure (high N, 1.36 % N) while that collected from the adjacent commercial farming area was classified as low quality manure (low N, 0.51 % N). The two manure types were applied in rates of 0, 15, 30 Mg ha−1. The treatments were arranged in a randomized complete block design with four replicates. When 15 and 30 Mg high and low N manure ha−1 were applied, the concentration of NO3–N in leachate exceeded the recommended 10 mg L−1 concentration in portable water by 15–104 and 53–174 % respectively. The substitution of 15 and 30 Mg of high N manure with 15 and 30 Mg ha−1 of low N manure reduced total N lost through leaching by 10–43 and 22–69 % respectively. Ground water contamination by nitrate overload can be considerably reduced by application of low N manure to vegetable crops

Home-based tuberculosis contact investigation in Uganda: a household randomised trial.

IntroductionThe World Health Organization (WHO) recommends household tuberculosis (TB) contact investigation in low-income countries, but most contacts do not complete a full clinical and laboratory evaluation.MethodsWe performed a randomised trial of home-based, SMS-facilitated, household TB contact investigation in Kampala, Uganda. Community health workers (CHWs) visited homes of index patients with pulmonary TB to screen household contacts for TB. Entire households were randomly allocated to clinic (standard-of-care) or home (intervention) evaluation. In the intervention arm, CHWs offered HIV testing to adults; collected sputum from symptomatic contacts and persons living with HIV (PLWHs) if ≥5 years; and transported sputum for microbiologic testing. CHWs referred PLWHs, children <5 years, and anyone unable to complete sputum testing to clinic. Sputum testing results and/or follow-up instructions were returned by automated SMS texts. The primary outcome was completion of a full TB evaluation within 14 days; secondary outcomes were TB and HIV diagnoses and treatments among screened contacts.ResultsThere were 471 contacts of 190 index patients allocated to the intervention and 448 contacts of 182 index patients allocated to the standard-of-care. CHWs identified 190/471 (40%) intervention and 213/448 (48%) standard-of-care contacts requiring TB evaluation. In the intervention arm, CHWs obtained sputum from 35/91 (39%) of sputum-eligible contacts and SMSs were sent to 95/190 (50%). Completion of TB evaluation in the intervention and standard-of-care arms at 14 days (14% versus 15%; difference -1%, 95% CI -9% to 7%, p=0.81) and yields of confirmed TB (1.5% versus 1.1%, p=0.62) and new HIV (2.0% versus 1.8%, p=0.90) diagnoses were similar.ConclusionsHome-based, SMS-facilitated evaluation did not improve completion or yield of household TB contact investigation, likely due to challenges delivering the intervention components

Hydrological processes and water resources management in a dryland environment II: Surface redistribution of rainfall within fields

International audienceSoil water movement was studied within fields on two different soil types, a red clay soil and a duplex soil of sand over clay, at the Romwe Catchment in southern Zimbabwe. Each study site comprised two fields and formed a surface water sub-catchment (1.0-2.4 ha) from which runoff was gauged. Soil moisture was measured in-situ at up to 20 locations within each sub-catchment over an entire cropping season and the following dry season. Maize was cultivated at both sites according to the farmers' normal cropping practice and crop yields were recorded. Surface redistribution of rainfall through localised runon and runoff was shown to be an important process in both sub-catchments with rainfall concentration factors between 0.2 and 2.7 for major rainfall events. This process was a key factor controlling deep drainage to groundwater. Results indicate that surface water redistribution is of particular importance for groundwater recharge in years with low or evenly distributed rainfall, when it would not otherwise have occurred. The soil water conditions created by surface redistribution of rainfall are also actively exploited by farmers who vary cropping practices within fields to maximise crop yields and reduce the risks of crop failure

Climate variability and change or multiple stressors? Farmer perceptions regarding threats to livelihoods in Zimbabwe and Zambia

Climate variability is set to increase, characterised by extreme conditions in Africa. Southern Africa will likely get drier and experience more extreme weather conditions, particularly droughts and floods. However, while climate risks are acknowledged to be a serious threat to smallholder farmers’ livelihoods, these risks do not exist in isolation, but rather, compound a multiplicity of stressors. It was important for this study to understand farmer perceptions regarding the role of climate risks within a complex and multifarious set of risks to farmers’ livelihoods. This study used both qualitative and quantitative methods to investigate farmers’ perceptions regarding threats to livelihoods in southern Zambia and south-western Zimbabwe. While farmers report changes in local climatic conditions consistent with climate variability, there is a problem in assigning contribution of climate variability and other factors to observed negative impacts on the agricultural and socio-economic system. Furthermore, while there is a multiplicity of stressors that confront farmers, climate variability remains the most critical and exacerbate livelihood insecurity for those farmers with higher levels of vulnerability to these stressor

Challenges with scale-up of GeneXpert MTB/RIF® in Uganda: a health systems perspective.

BACKGROUND: Many high burden countries are scaling-up GeneXpert® MTB/RIF (Xpert) testing for tuberculosis (TB) using a hub-and-spoke model. However, the effect of scale up on reducing TB has been limited. We sought to characterize variation in implementation of referral-based Xpert TB testing across Uganda, and to identify health system factors that may enhance or prevent high-quality implementation of Xpert testing services. METHODS: We conducted a cross-sectional study triangulating quantitative and qualitative data sources at 23 community health centers linked to one of 15 Xpert testing sites between November 2016 and May 2017 to assess health systems infrastructure for hub-and-spoke Xpert testing. Data sources included a standardized site assessment survey, routine TB notification data, and field notes from site visits. RESULTS: Challenges with Xpert implementation occurred at every step of the diagnostic evaluation process, leading to low overall uptake of testing. Of 2192 patients eligible for TB testing, only 574 (26%) who initiated testing were referred for Xpert testing. Of those, 54 (9.4%) were Xpert confirmed positive just under half initiated treatment within 14 days (n = 25, 46%). Gaps in required infrastructure at 23 community health centers to support the hub-and-spoke system included lack of refrigeration (n = 14, 61%) for sputum testing and lack of telephone/mobile communication (n = 21, 91%). Motorcycle riders responsible for transporting sputum to Xpert sites operated variable with trips once, twice, or three times a week at 10 (43%), nine (39%) and four (17%) health centers, respectively. Staff recorded Xpert results in the TB laboratory register at only one health center and called patients with positive results at only two health centers. Of the 15 Xpert testing sites, five (33%) had at least one non-functioning module. The median number of tests per day was 3.57 (IQR 2.06-4.54), and 10 (67%) sites had error/invalid rates > 5%. CONCLUSIONS: Although Xpert devices are now widely distributed throughout Uganda, health system factors across the continuum from test referral to results reporting and treatment initiation preclude effective implementation of Xpert testing for patients presenting to peripheral health centers. Support for scale up of innovative technologies should include support for communication, coordination and health systems integration

Building adaptive capacity to cope with increasing vulnerability due to climatic change in Africa – A new approach

The world community faces many risks from climate change, with most scenarios indicating higher temperatures and more erratic rainfall in Africa. Predictions for southern Africa suggest a general decrease in total seasonal rainfall, accompanied by more frequent in-season dry spells that will significantly impact crop and livestock production, and hence economic growth in the region. The hardest hit will be the rural poor in the drier areas, where crop failure due to drought is already common and chronic food emergencies afflict the region in most years. Lessons can be learnt on how the rural poor currently cope with the vagaries of climate and these can be used to help them adapt their current production systems to the future threats of further climate change. But this assumes the institutions that work towards the economic empowerment of the rural poor have the requisite skills to understand their current coping strategies and how adaptation can be facilitated. A new initiative led by Midlands State University and the Zambian Meteorological Office proposes that improving the ability of institutions that train the ‘Future Change Agents’, who will subsequently support smallholder communities in adapting their agricultural practices to current climate variability, is the first step in building adaptive capacity to cope with future climate change. The capacity of African scientists, regional organizations and decision-makers in dealing with the issues of climate change and adaptation will be enhanced on a continuing basis, and the impacts of their agricultural development programs improve