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

Predicting toxic heavy metal movements in upper Sanyati catchment in the midlands province in Zimbabwe

The study assessed toxic heavy metal concentrations in the upper Sanyati catchment in the Midlands Province in Zimbabwe and predicted their movements and potential impacts on ground water quality. Topographic surveying was used to determine borehole locations, elevations, hydraulic conductivity and water yields. Monthly ground water samples were analyzed to determine concentrations of Cr, Pb, Cd and Ni for a period of two-years. The results obtained for the wet season showed mean concentration levels of Cr, Pb, Cd and Ni at 0.25, 0.015, 0.042 and 0.031mg/L respectively. Dry season mean concentration levels for Cr, Pb, Cd and Ni were 0.15, 0.07, 0.06 and 0.025 mg/L respectively.  Water samples from boreholes located in areas where mining, mineral processing and agricultural activities were dominant, yielded the highest values of toxic heavy metals. Dilution Attenuation Factor (DAF) for each toxic heavy metal was calculated to observe metal behaviour along the contaminant path for each season. The results showed seasonal variation in the spatial distribution of each toxic heavy metal during the wet season between October to March and during the dry season between April to September. Overall, research results showed that concentrations of Cr, Pb, Cd and Ni were above the standard limits set by the World Health Organization.Key Words: Heavy metals; Hydraulic conductivity; Ground water transportation; Contamination; Attenuation; Photometry

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

Feasibility of a streamlined tuberculosis diagnosis and treatment initiation strategy.

OBJECTIVE: To assess the feasibility of a streamlined strategy for improving tuberculosis (TB) diagnostic evaluation and treatment initiation among patients with presumed TB. DESIGN: Single-arm interventional pilot study at five primary care health centers of a streamlined, SIngle-saMPLE (SIMPLE) TB diagnostic evaluation strategy: 1) examination of two smear results from a single spot sputum specimen using light-emitting diode fluorescence microscopy, and 2) daily transportation of smear-negative sputum samples to Xpert® MTB/RIF testing sites. RESULTS: Of 1212 adults who underwent sputum testing for TB, 99.6% had two smears examined from the spot sputum specimen. Sputum was transported for Xpert testing within 1 clinic day for 83% (907/1091) of the smear-negative patients. Of 157 (13%) patients with bacteriologically positive TB, 116 (74%) were identified using sputum smear microscopy and 41 (26%) using Xpert testing of smear-negative samples. Anti-tuberculosis treatment was initiated in 142 (90%) patients with bacteriologically positive TB, with a median time to treatment of 1 day for smear-positive patients and 6 days for smear-negative, Xpert-positive patients. CONCLUSION: The SIMPLE TB strategy led to successful incorporation of Xpert testing and rapid treatment initiation in the majority of patients with bacteriologically confirmed TB in a resource-limited setting

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

Securing Africa’s health sovereignty : why investing in science and innovation matters

This paper aims at provoking broad-based dialogues and debates on ways and means of securing Africa’s health sovereignty. It argues that health sovereignty is about the realization of specific national constitutional and policy objectives on citizens’ access to and enjoyment of good health, resilient to COVID-19 and related disease pandemics. The paper also emphasizes the urgency of African countries fulfilling their commitments under global and regional declarations on health research. Investing in research, knowledge and innovation is critical to fight and win the war against COVID-19 and other diseases that undermine economic productivity and competitiveness of African countries. There is also a need for venture capitalists to demonstrate bankable ideas emanating from the science academies and funded by National Science Foundations. The base teachings at school level need to significantly invest in the “African philosophy” to create a shift in mind-set from the “grab and own without use mentality that is currently predominant on the continent. The paper recommends that executive, political and science leadership are needed to strengthen national health research and innovation systems through improved evidence-based policy implementation. With these thrusts working effectively together, rather than in silos, will afford the African continent to emerge victoriously in the combat against COVID-19 and other disease burdens

Activity and Interactions of Liposomal Antibiotics in Presence of Polyanions and Sputum of Patients with Cystic Fibrosis

BACKGROUND:To compare the effectiveness of liposomal tobramycin or polymyxin B against Pseudomonas aeruginosa in the Cystic Fibrosis (CF) sputum and its inhibition by common polyanionic components such as DNA, F-actin, lipopolysaccharides (LPS), and lipoteichoic acid (LTA). METHODOLOGY:Liposomal formulations were prepared from a mixture of 1,2-Dimyristoyl-sn-Glycero-3-Phosphocholine (DMPC) or 1,2-Dipalmitoyl-sn-Glycero-3-Phosphocholine (DPPC) and Cholesterol (Chol), respectively. Stability of the formulations in different biological milieus and antibacterial activities compared to conventional forms in the presence of the aforementioned inhibitory factors or CF sputum were evaluated. RESULTS:The formulations were stable in all conditions tested with no significant differences compared to the controls. Inhibition of antibiotic formulations by DNA/F-actin and LPS/LTA was concentration dependent. DNA/F-actin (125 to 1000 mg/L) and LPS/LTA (1 to 1000 mg/L) inhibited conventional tobramycin bioactivity, whereas, liposome-entrapped tobramycin was inhibited at higher concentrations--DNA/F-actin (500 to 1000 mg/L) and LPS/LTA (100 to 1000 mg/L). Neither polymyxin B formulation was inactivated by DNA/F-actin, but LPS/LTA (1 to 1000 mg/L) inhibited the drug in conventional form completely and higher concentrations of the inhibitors (100 to 1000 mg/L) was required to inhibit the liposome-entrapped polymyxin B. Co-incubation with inhibitory factors (1000 mg/L) increased conventional (16-fold) and liposomal (4-fold) tobramycin minimum bactericidal concentrations (MBCs), while both polymyxin B formulations were inhibited 64-fold. CONCLUSIONS:Liposome-entrapment reduced antibiotic inhibition up to 100-fold and the CFU of endogenous P. aeruginosa in sputum by 4-fold compared to the conventional antibiotic, suggesting their potential applications in CF lung infections