28 research outputs found

    Household Livelihoods, Marketing And Resource Impacts* A Case Study Of Bark Products In Eastern Zimbabwe

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    An IES Working Paper.Markets for craft and medicinal products derived from the bark of three tree species were assessed in rural and urban areas of Zimbabwe. Bark crafts from Adansonia digitata (baobab) are widely sold in these regions. The number of sellers has increased since the 1980s and has remained relatively stable since then. Competition for local purchasers is provided by domestic and imported substitutes. Most baobab craft items are relatively bulky and the export market for them is largely limited to affluent travellers from South Africa. This is a relatively localized market. Seasonality in baobab craft production and sales is pronounced in the rural area. Prices are transparent and arbitrage appears to occur. This is not the case in the markets for the bark of Warburgia salutaris, which is used as a traditional medicine. There are relatively few sellers, prices do not exhibit regionally consistent patterns and this species appears to have become locally extinct. Bark of Berchemia discolor is not highly commercialised in this region; no sales of this bark were observed in the course of the study.Funding for the study was provided by Canadian International Development Agency (CIDA) through the Agro-forestry Southern Africa project and the World Wide Fund for Nature (WWF) People and Plants Initiativ

    The Great Green Forest is here and expanding all on its own: A call for action

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    Prosopis juliflora is recognized as one of the most invasive tree species worldwide. Following widespread introductions throughout arid and semi-arid regions of Africa and throughout the world, it has spread rapidly, threatening natural ecosystems and livelihoods. Control through utilization as a resource is now accepted as the way forward in developing countries, but efforts have so far been uncoordinated, with only isolated impacts. This paper reports on the global state of knowledge and recent advances, but focuses on prosopis-related research and innovations from IGAD member countries; the successes, failures, challenges and opportunities. It underlines the need to build and apply scientific knowledge to scale up new, resilient, drought-proof livelihood options in the Greater Horn of Africa and elsewhere where introduced, from value-added prosopis wood and non wood products. The authors estimate that there are at least five million hectares of prosopis forest across the region of the perhaps ten million throughout Africa, and growing significantly in extent every year. Experiences from the native range such as in Peru are well documented, where community associations sustainably manage and make a living from fuel, fodder, food, honey and timber from their prosopis forests. Efforts in Ethiopia, Djibouti and Kenya have had mixed results, but milling the sweet protein-rich pods into animal feed is becoming increasingly popular with the introduction of appropriate small scale technologies. Its use as a human food ingredient has also been promoted, though with little uptake, but there is sharp rise in the use of prosopis charcoal in the region, and the possibility of electricity generation using wood chips (bioenergy), with the transfer of experiences from India where there are at least 15 power stations fueled entirely by prosopis. But much more can be done by applying scientific knowledge and innovation to enhance the role of prosopis in improving food security, climate change mitigation and adaptation, and building resilience for millions of the poorest rural and urban people in the Greater Horn of Africa, with great potential for exchange and scaling up in other arid areas in Africa, Asia and the Americas. This paper is a call to the African Union, national governments, IGAD, IFAD, FAO, the Arab League and other international, regional and bilateral donors, to come together and support a regional research and development programme to push the frontiers on prosopis management and utilization and develop a transnational strategy, as the impacts are potentially enormous and immediate. The initial objectives are to take stock of existing knowledge and practices, assess prosopis forest areas throughout the region, estimate wood and pod volumes and production rates, document prosopis management and utilization experiences, enhance South-South knowledge sharing, and rapidly and effectively scale up the successes

    Sustainable Management of Rangelands: An Assessment of Invasion Cover Trajectories and Their Contribution to Invasion Management in Marigat Sub-County, Kenya

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    Invasive alien species have complex spatiotemporal patterns of spread beyond geographical and jurisdictional boundaries. This calls for a coordinated management approach that is spatially explicit, extends beyond individual plot levels, and incorporates land users’ perceptions and decisions. This study, therefore, aims at assessing spatiotemporal invasion trajectories of the invasive tree Prosopis juliflora in Baringo County, Kenya, and evaluating their possible relation to land users’ management decisions. Pre-classified land cover data over a seven-year time period (1988–2016) were reclassified based on the presence or absence of P. juliflora and integrated into ArcGIS to produce P. juliflora cover trajectories for analysis. The spatiotemporal analysis of Prosopis invasion dynamics yields trajectories that can be linked to underlying land users’ management decisions. Areas that remained free of Prosopis since their first clearance were primarily areas where the invasion would cause the highest loss in terms of income or opportunity costs; areas that were never cleared since they were first invaded tended to be areas where no one could be personally held accountable for their management, while the abandonment of management followed by re-invasion appeared to be linked to different drivers, including diversification of livelihoods and lower market prices for horticultural products. Our findings indicate that invasion trajectories are useful in informing existing management strategies to adopt context-based invasive species management practices. The study recommends scaling up the trajectory analysis approach to be replicated in large-scale invasion management strategies. Since it requires considerable finances and time to conduct such analyses on raw satellite imagery, we suggest further research on how to simplify the approach to make it easily and efficiently replicable for large-scale applications

    Mannose-rich glycosylation patterns on HIV-1 subtype C gp120 and sensitivity to the lectins, Griffithsin, Cyanovirin-N and Scytovirin.

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    Griffithsin (GRFT), Cyanovirin-N (CV-N) and Scytovirin (SVN) are lectins that inhibit HIV-1 infection by binding to multiple mannose-rich glycans on the HIV-1 envelope glycoproteins (Env). Here we show that these lectins neutralize subtype C primary virus isolates in addition to Env-pseudotyped viruses obtained from plasma and cervical vaginal lavages. Among 15 subtype C pseudoviruses, the median IC50 values were 0.4, 1.8 and 20.1 nM for GRFT, CV-N and SVN, respectively, similar to what was found for subtype B and A. Analysis of Env sequences suggested that concomitant lack of glycans at positions 234 and 295 resulted in natural resistance to these compounds, which was confirmed by site-directed mutagenesis. Furthermore, the binding sites for these lectins overlapped that of the 2G12 monoclonal antibody epitope, which is generally absent on subtype C Env. This data support further research on these lectins as potential microbicides in the context of HIV-1 subtype C infection

    HIV-1 co-receptor usage:influence on mother-to-child transmission and pediatric infection

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    Viral CCR5 usage is not a predictive marker of mother to child transmission (MTCT) of HIV-1. CXCR4-using viral variants are little represented in pregnant women, have an increased although not significant risk of transmission and can be eventually also detected in the neonates. Genetic polymorphisms are more frequently of relevance in the child than in the mother. However, specific tissues as the placenta or the intestine, which are involved in the prevalent routes of infection in MTCT, may play an important role of selective barriers

    The cost‐effectiveness of prophylaxis strategies for individuals with advanced HIV starting treatment in Africa

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    Introduction Many HIV‐positive individuals in Africa have advanced disease when initiating antiretroviral therapy (ART) so have high risks of opportunistic infections and death. The REALITY trial found that an enhanced‐prophylaxis package including fluconazole reduced mortality by 27% in individuals starting ART with CD4 <100 cells/mm3. We investigated the cost‐effectiveness of this enhanced‐prophylaxis package versus other strategies, including using cryptococcal antigen (CrAg) testing, in individuals with CD4 <200 cells/mm3 or <100 cells/mm3 at ART initiation and all individuals regardless of CD4 count. Methods The REALITY trial enrolled from June 2013 to April 2015. A decision‐analytic model was developed to estimate the cost‐effectiveness of six management strategies in individuals initiating ART in the REALITY trial countries. Strategies included standard‐prophylaxis, enhanced‐prophylaxis, standard‐prophylaxis with fluconazole; and three CrAg testing strategies, the first stratifying individuals to enhanced‐prophylaxis (CrAg‐positive) or standard‐prophylaxis (CrAg‐negative), the second to enhanced‐prophylaxis (CrAg‐positive) or enhanced‐prophylaxis without fluconazole (CrAg‐negative) and the third to standard‐prophylaxis with fluconazole (CrAg‐positive) or without fluconazole (CrAg‐negative). The model estimated costs, life‐years and quality‐adjusted life‐years (QALY) over 48 weeks using three competing mortality risks: cryptococcal meningitis; tuberculosis, serious bacterial infection or other known cause; and unknown cause. Results Enhanced‐prophylaxis was cost‐effective at cost‐effectiveness thresholds of US300andUS300 and US500 per QALY with an incremental cost‐effectiveness ratio (ICER) of US157perQALYintheCD4<200cells/mm3populationprovidingenhanced‐prophylaxiscomponentsaresourcedatlowestavailableprices.TheICERreducedinmoreseverelyimmunosuppressedindividuals(US157 per QALY in the CD4 <200 cells/mm3 population providing enhanced‐prophylaxis components are sourced at lowest available prices. The ICER reduced in more severely immunosuppressed individuals (US113 per QALY in the CD4 <100 cells/mm3 population) and increased in all individuals regardless of CD4 count (US722perQALY).Resultsweresensitivetopricesoftheenhanced‐prophylaxiscomponents.Enhanced‐prophylaxiswasmoreeffectiveandlesscostlythanallCrAgtestingstrategiesasenhanced‐prophylaxisstillconveyedhealthgainsinCrAg‐negativepatientsandsavingsfromtargetingprophylaxisbasedonCrAgstatusdidnotcompensateforcostsofCrAgtesting.CrAgtestingstrategiesdidnotbecomecost‐effectiveunlessthepriceofCrAgtestingfellbelowUS722 per QALY). Results were sensitive to prices of the enhanced‐prophylaxis components. Enhanced‐prophylaxis was more effective and less costly than all CrAg testing strategies as enhanced‐prophylaxis still conveyed health gains in CrAg‐negative patients and savings from targeting prophylaxis based on CrAg status did not compensate for costs of CrAg testing. CrAg testing strategies did not become cost‐effective unless the price of CrAg testing fell below US2.30. Conclusions The REALITY enhanced‐prophylaxis package in individuals with advanced HIV starting ART reduces morbidity and mortality, is practical to administer and is cost‐effective. Efforts should continue to ensure that components are accessed at lowest available prices

    Late Presentation With HIV in Africa: Phenotypes, Risk, and Risk Stratification in the REALITY Trial.

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    This article has been accepted for publication in Clinical Infectious Diseases Published by Oxford University PressBackground: Severely immunocompromised human immunodeficiency virus (HIV)-infected individuals have high mortality shortly after starting antiretroviral therapy (ART). We investigated predictors of early mortality and "late presenter" phenotypes. Methods: The Reduction of EArly MortaLITY (REALITY) trial enrolled ART-naive adults and children ≄5 years of age with CD4 counts .1). Results: Among 1711 included participants, 203 (12%) died. Mortality was independently higher with older age; lower CD4 count, albumin, hemoglobin, and grip strength; presence of World Health Organization stage 3/4 weight loss, fever, or vomiting; and problems with mobility or self-care at baseline (all P < .04). Receiving enhanced antimicrobial prophylaxis independently reduced mortality (P = .02). Of five late-presenter phenotypes, Group 1 (n = 355) had highest mortality (25%; median CD4 count, 28 cells/”L), with high symptom burden, weight loss, poor mobility, and low albumin and hemoglobin. Group 2 (n = 394; 11% mortality; 43 cells/”L) also had weight loss, with high white cell, platelet, and neutrophil counts suggesting underlying inflammation/infection. Group 3 (n = 218; 10% mortality) had low CD4 counts (27 cells/”L), but low symptom burden and maintained fat mass. The remaining groups had 4%-6% mortality. Conclusions: Clinical and laboratory features identified groups with highest mortality following ART initiation. A screening tool could identify patients with low CD4 counts for prioritizing same-day ART initiation, enhanced prophylaxis, and intensive follow-up. Clinical Trials Registration: ISRCTN43622374.REALITY was funded by the Joint Global Health Trials Scheme (JGHTS) of the UK Department for International Development, the Wellcome Trust, and Medical Research Council (MRC) (grant number G1100693). Additional funding support was provided by the PENTA Foundation and core support to the MRC Clinical Trials Unit at University College London (grant numbers MC_UU_12023/23 and MC_UU_12023/26). Cipla Ltd, Gilead Sciences, ViiV Healthcare/GlaxoSmithKline, and Merck Sharp & Dohme donated drugs for REALITY, and ready-to-use supplementary food was purchased from Valid International. A. J. P. is funded by the Wellcome Trust (grant number 108065/Z/15/Z). J. A. B. is funded by the JGHTS (grant number MR/M007367/1). The Malawi-Liverpool–Wellcome Trust Clinical Research Programme, University of Malawi College of Medicine (grant number 101113/Z/13/Z) and the Kenya Medical Research Institute (KEMRI)/Wellcome Trust Research Programme, Kilifi (grant number 203077/Z/16/Z) are supported by strategic awards from the Wellcome Trust, United Kingdom. Permission to publish was granted by the Director of KEMRI. This supplement was supported by funds from the Bill & Melinda Gates Foundation

    Biology and Impacts of Pacific Island Invasive Species. 6. Prosopis pallida

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    Is HIV-1 evolving to a less virulent form in humans?

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