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

Influence of communal area grazing management system on the nutritive value of forages selected by cattle in a semi-arid area of Zimbabwe

A study was conducted to determine the effect of grazing management system on the nutritive value of forages selected by cattle. Animals were observed while grazing and the grazed samples were collected. The samples were analysed for chemical composition and digestibility. There were significant (P0.05). These findings suggest that grazing schemes tended to compromise the quality of forages selected under poor range conditions, possibly due to limited range resources. The ability of cattle under traditional grazing system to switch effectively among the different range resources might have enhanced the quality of forages selected

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

Agricultural innovation platform as a tool for development oriented research: Lessons and challenges in the formation and operationalization

The emergence of Integrated Agricultural Research for Development (IAR4D) presents an opportunity to address any development problem. It involves innovative principles and an integrated research agenda while recognizing the need for greater organizational capacities among stakeholders in agriculture. Operationalization of IAR4D revolves around successful establishment and operation of an Agricultural Innovation Platform (AIP). Agricultural Innovation Platforms are being implemented in Lake Kivu Pilot Learning Site (LKPLS) of the Sub-Saharan Africa Challenge Programme, covering three countries (Uganda, Rwanda and Democratic Republic of Congo) with widely differing social political environments to address agricultural development challenges. This paper presents the processes, general guidelines lessons and experiences pertaining to “good practices” for organising and forming AIPs in the LKPLS. The life of AIPs covers three phases, namely; pre-formation, formation and post formation. The lessons and experiences are shared across 6 stages of AIP formation, namely; Identification of a research and developmental challenge(s), Site selection, Consultative and scoping study, Visioning and Stakeholder analysis, Development of action plans and Implementation of the action plans. Emerging lessons highlight AIPs as grounds and pillars for multi-level, multi-stakeholder interactions to identify, understand and address a complex challenge, concomitant emerging issues and learning towards achieving the agreed vision. Agricultural Innovation Platform formation is a dynamic, highly context specific process that incorporates all essential ingredients for successful innovation at once and provides an opportunity for local innovations to bear while at the same time nourishing on introduced innovations. In AIP formation, the recognition and value of indigenous knowledge and capitalization on prevailing policy, institutional setting and involvement of local leadership is vital. The form, nature and time taken by AIP formation process depends on both the conceptual and local context, quality of facilitation, socio-economic, culture, biophysical, political environment in which a common challenge and/or opportunity is identified and on the capacity of stakeholders to comprehend the Innovation Systems Approach (ISA). The process of AIP formation was faster in creating win-wins when market led. Strong leadership, strategic partnership, information flow, interactions and dealing with recurrent challenges during the AIP formation process are critical in fostering innovations. The major challenges included capacitating the stakeholders in requisite skills and dealing with persistent “handout-syndrome”

Institutional Innovations for Building Impact-oriented Agricultural Research, Knowledge and Development Institutions

The central development question in African agriculture is how to catalyze a more competitive, equitable and sustainable agricultural growth within the context of smallholder production systems, inefficient agricultural marketing, inefficient investments by private sector amidst degradation prone natural resources base (Lynam and Blackie, 1994; IAC, 2004; World bank, 2006 ). Concerted scholarly analyses of Science and Technology (S&T) strategies have given birth to Integrated Agricultural Research for Development (IAR4D) an organizing concept of the Innovation Systems Approach (ISA) as the promise holder. It is hypothesized that the generation, diffusion and application of impactful innovations critically depend on systemic integration of knowledge systems that promote communication, interaction and cooperation between agricultural research, education, extension, farmers, private sector and policy regulatory systems. This paper examines how the different institutional innovations arising from various permutations of linkages and interactions of ARD organizations (national, international advanced agricultural research centres and universities) influenced the different outcomes in addressing identified ARD problems. A multi-institutional, multi-disciplinary phased Participatory Action Research approach was used to pool knowledge to address outstanding and emerging challenges in three countries (DRC, Rwanda and Uganda) with 2, 16 and 24 years out of conflict, respectively) of the Lake Kivu Pilot Learning Site. A landmark institutional innovation was the participatory establishment of twelve (12) Innovation Platforms as tools for pooling knowledge across the agricultural business, education, research and extension systems. The knowledge “pool” was to generate, diffuse and apply innovations to reduce transactions costs and create value chain based “win-win” situations. A number of innovations (e.g. International Public Goods-IPGs, market binding contracts, registered brands and/or certification processes, diversity, density and quality of networks/collective action, bulking centres, ICT application and depth of knowledge pools) were initiated. There were major breakthroughs which included bringing on board non-traditional private sector and policy maker partners, overcoming the predominant “farmer handout syndrome”, building consensus and addressing common interest challenge. Making markets work, bringing various stakeholders including universities to the community and vice-versa, appreciation of indigenous knowledge system, propelling collective soil and water conservation and demand/utilization of technologies hitherto on-shelf were other very significant breakthroughs. Sustainable operations of the Innovation Systems knowledge “pool” nurturing institutional learning were ensured through the availability of a “functional body”. The body undertook the social enterprise of organizing farmers and traders, facilitating/brokering ARD organization linkages by using multi-media to build social capital to overcome emergent knowledge, credit, market, technology and resource degradation challenges under different policy regulatory systems

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