Surviving in a Socio-Economic Crisis: Strategies of Low Income Urban Households in Dzivaresekwa: Zimbabwe

Magister Philosophiae (Land and Agrarian Studies) - MPhil(LAS)For close to a decade, Zimbabwe has experienced a protracted socio-economic crisis. Although it is affecting both rural and urban areas, major forms of formal safety nets by the Government and Non-Governmental Organisations have been confined to rural areas. On the other hand the virtual collapse of the formal food marketing system in urban areas and the high formal unemployment rates have contributed to increased vulnerability of low income urban households to food insecurity. Using qualitative research methods, the study set out to understand livelihoods of low income urban households in Dzivaresekwa. In particular strategies low income households employ to cope with the negative macro-economic environment prevailing in Zimbabwe.South Afric

Situational analysis study of the agriculture sector in Uganda

Uganda submitted its first Nationally Determined Contribution (NDC) in 2015 to the UNFCCC through which it committed to reduce approximately 22% of national GHG emissions in 2030 compared to business-as-usual of 49 million MtCO2eq. The country is currently in the process of updating its NDC in accordance with decision 1/CP.21 of the UNFCCC. As part of the process, the Ministry of Agriculture, Animal Industry and Fisheries (MAAIF) is leading the process of defining the sector’s medium- and long-term low emissions, climate development pathway (Agricultural LTS) in order to identify concrete short-, medium- and long term adaptation and mitigation options that would inform updating of the agricultural component of the Nationally Determined Contributions (NDCs) and successive NDCs. As a precursor to the LTS, understanding the status of the sector (baseline) is critical. This situational analysis study assessed the current status and trends of the agriculture sector in Uganda and identified opportunities to transform the sector towards a low carbon and climate resilient development pathway

Anaplasma marginale Actively Modulates Vacuolar Maturation During Intracellular Infection of Its Tick Vector, Dermacentor andersoni

ABSTRACT Tick-borne transmission of bacterial pathogens in the order Rickettsiales is responsible for diverse infectious diseases, many of them severe, in humans and animals. Transmission dynamics differ among these pathogens and are reflected in the pathogen-vector interaction. Anaplasma marginale has been shown to establish and maintain infectivity within Dermacentor spp. for weeks to months while escaping the complex network of vacuolar peptidases that are responsible for digestion ofthe tick blood meal. How this prolonged maintenance of infectivity in a potentially hostile environment is achieved has been unknown. Using the natural vector Dermacentor andersoni, we demonstrated that A. marginale-infected tick vacuoles (AmVs) concurrently recruit markers of the early endosome (Rab5), recycling endosome (Rab4 and Rab11), and late endosome (Rab7), are maintained near neutral pH, do not fuse with lysosomes, exclude the protease cathepsin L, and engage the endoplasmic reticulum and Golgi apparatus for up to 21 days post infection. Maintenance of this safe vacuolar niche requires active A. marginale protein synthesis; in its absence, the AmVs mature into acidic, protease-active phagolysosomes. Identification of this bacterially directed modeling of the tick midgut endosome provides a mechanistic basis for examination of the differences in transmission efficiency observed among A. marginale strains and among vector populations. IMPORTANCE Ticks transmit a variety of intracellular bacterial pathogens that cause significant diseases in humans and animals. For successful transmission, these bacterial pathogens must first gain entry into the tick midgut digestive cells, avoid digestion, and establish a replicative niche without harming the tick vector. Little is known about how this replicative niche is established and maintained. Using the ruminant pathogen A. marginale and its natural tick vector, D. andersoni, this study characterized the features of the A. marginale niche in the tick midgut and demonstrates that A. marginale protein synthesis is required for the maintenance of this niche. This work opens a new line of inquiry about the pathogen effectors and their targets within the tick that mediate tick pathogen interactions and ultimately serve as the determinants of pathogen success

Descriptive epidemiology of African horse sickness in Zimbabwe

A study of the prevalence of African horse sickness in horses was conducted, using records from two private equine practices in Harare for the period 1998–2004. Results indicated a higher prevalence of the disease in horses in Zimbabwe in the late rainy season (March – May). Age of the horse was found to be a significant risk factor, with foals or yearlings appearing to be 1.80 times more likely to contract the disease compared with horses older than two years. The case fatality rate in foals or yearlings was also higher than in older age groups, but this difference was not significant. The vaccination status was an important risk factor, with vaccinated horses 0.12 times less likely to die from the disease compared with unvaccinated horses. Young, unvaccinated horses therefore seem to be the most susceptible to the disease and have greater chances of fatality. This study highlights the importance of adequately protecting horses against African horse sickness by providing immunisation through vaccination and discusses the need to review current vaccination strategies being practiced in Zimbabwe

The Politics of Seed Relief in Zimbabwe

A decade of economic and political turmoil in Zimbabwe, as well as a period of radical land reform which reconfigured the country's agricultural sector, dramatically affected its seed system, reducing the supply of quality seeds and undermining regulatory control. The collapse of the seed system was exacerbated by seed relief programmes implemented by the government and aid agencies, which bypassed the normal market chain. In 2010, aid agencies experimented with ‘market?friendly’ input programmes which also created distortions and were vulnerable to political interference. In resource?constrained settings, subsidy programmes, no matter what design, became objects of political contestation. This article aims to understand how Zimbabwe can rebuild a seed system appropriate to the post?land reform context by asking questions about the underlying political economy of this process, examining the implementation of the input delivery approaches

The Pathogen-Occupied Vacuoles of Anaplasma phagocytophilum and Anaplasma marginale Interact with the Endoplasmic Reticulum

The genus Anaplasma consists of tick-transmitted obligate intracellular bacteria that invade white or red blood cells to cause debilitating and potentially fatal infections. A. phagocytophilum, a human and veterinary pathogen, infects neutrophils to cause granulocytic anaplasmosis. A. marginale invades bovine erythrocytes. Evidence suggests that both species may also infect endothelial cells in vivo. In mammalian and arthropod host cells, A. phagocytophilum and A. marginale reside in host cell derived pathogen-occupied vacuoles (POVs). While it was recently demonstrated that the A. phagocytophilum-occupied vacuole (ApV) intercepts membrane traffic from the trans-Golgi network, it is unclear if it or the A. marginale-occupied vacuole (AmV) interacts with other secretory organelles. Here, we demonstrate that the ApV and AmV extensively interact with the host endoplasmic reticulum (ER) in endothelial, myeloid, and/or tick cells. ER lumen markers, calreticulin, and protein disulfide isomerase, and the ER membrane marker, derlin-1, were pronouncedly recruited to the peripheries of both POVs. ApV association with the ER initiated early and continued throughout the infection cycle. Both the ApV and AmV interacted with the rough ER and smooth ER. However, only derlin-1-positive rough ER derived vesicles were delivered into the ApV lumen where they localized with intravacuolar bacteria. Transmission electron microscopy identified multiple ER-POV membrane contact sites on the cytosolic faces of both species\u27 vacuoles that corresponded to areas on the vacuoles\u27 lumenal faces where intravacuolar Anaplasma organisms closely associated. A. phagocytophilum is known to hijack Rab10, a GTPase that regulates ER dynamics and morphology. Yet, ApV-ER interactions were unhindered in cells in which Rab10 had been knocked down, demonstrating that the GTPase is dispensable for the bacterium to parasitize the ER. These data establish the ApV and AmV as pathogen-host interfaces that directly engage the ER in vertebrate and invertebrate host cells and evidence the conservation of ER parasitism between two Anaplasma species

LAND USE/COVER CHANGE PATTERNS IN HIGHLAND ECOSYSTEMS OF LAKE BUNYONYI CATCHMENT IN WESTERN UGANDA

Land use and cover changes influence the livelihood and degradation of fragile ecosystems. The extents of these changes in pattern were investigated in Lake Bunyonyi Catchment which lies in the South Western Highlands of Uganda. The dynamics and magnitude of land use and cover changes were assessed using Landsat (TM/ETM+) satellite images and collection of socio-economic data through interviews. The images were processed and analysed using the mean-shift image segmentation algorithm to cluster and quantify the land use and cover features. The study noted that in the assessment period 1987-2014, the small-scale farmlands, open water and grasslands remained quasi constant; while the woodlots followed a quadratic trend, with the lowest acreage experienced in 2000. The tropical high forests and wetlands cover types experienced significant decline over the years (P<0.05). Patches of small-scale farmlands, woodlots, and wetland interchangeably lost or gained more land dependant on climate variability. Even though the tropical high forest lost more than it gained, it only gained and lost to small scale farmland and woodlots; while grassland mainly lost to small scale farmland and woodlots.L\u2019occupation du sol et les changements de couverture influencent la subsistance et la d\ue9gradation des \ue9cosyst\ue8mes fragiles. La tendance des niveaux de ces changements \ue9taient \ue9valu\ue9e dans le basin versant du lac Bunyonyi qui relie les r\ue9gions montagneuses du Sud-Ouest d\u2019Ouganda. Les dynamiques et l\u2019 envergure d\u2019utilisaton de la terre et les changements de couverture \ue9taient \ue9valu\ue9es en utilisant les images du satellite Landsat (TM/ETM+) et la collecte des donn\ue9es socio-\ue9conomiques \ue0 travers des interviews. Les images \ue9taient trait\ue9es et analy\ue9es en utilisant l\u2019algorithme de segmentation de passage-moyen-d\u2019image pour grouper et quantifier les occupations du sol et les caract\ue9ristiques de la couverture. L\u2019\ue9tude a montr\ue9 que dans la p\ue9riode d\u2019\ue9valuation de 1987-2014, la petite \ue9tendue de terres cultivables, l\u2019eau libre et les prairies sont demeur\ue9es quasi constantes; tandis que les terres bois\ue9es ont suivi une tendance quadratique, avec la plus petite superficie observ\ue9e en l\u2019an 2000. Les grandes for\ueats tropicales et les zones humides ont exp\ue9riment\ue9 un d\ue9clin significatif au cours des ann\ue9es (P<0.05). Les petites parcelles de terres agricoles, les terres bois\ue9es, et les zones humides indistinctement ont perdu et gagn\ue9 plus de terres d\ue9pendamment de la variabilit\ue9 climatique. Bien que la grande for\ueat tropicale aie perdu plus qu\u2019elle en a gagn\ue9e; elle a seulement perdu de tr\ue8s petites \ue9tendues de terres agricoles et bois\ue9es; alors que les prairies ont principalement perdu de tr\ue8s petites \ue9tendues de terres agricoles et bois\ue9es

Analysis of surface roughness in relation to soil loss and runoff at high rainfall intensities.

The decay of roughness is an important factor governing surface processes such as infiltration and soil erosion. Thus the decay of surface roughness under different surface conditions was investigated and related to quantitative amounts of soil loss, runoff and sediment concentration in a laboratory experiment. Rainfall with an intensity of 128 mm/h was applied to a bare or mulched surfaces of a sandy loam soil with known surface roughness at specified time intervals. The decay of roughness as expressed by roughness ratio, in this experiment, was better predicted when related to an exponential function of the square root of cumulative kinetic energy of rainfall rather than with the cumulative rainfall. The roughness decay equations in literature did not predict breakdown under mulched surfaces accurately. Thus the exponent parameters of the roughness decay equations were adjusted to reflect the reduced decay occurring under mulched surfaces. In a bare soil, regression equations expressing the dependent variables as a function of initial roughness index were significant, but with low coefficients of determination, being 0.39 for soil loss, 0.12 for runoff and 0.36 for sediment concentration. In addition to initial roughness index, cumulative kinetic energy of rainfall was further included in the regressions. This led to an increase in coefficients of determination, which was 0.81 for soil loss, 0.74 for runoff and 0.49 for sediment concentration. The coefficients of determination (0.87 for soil loss, 0.85 for runoff and 0.51 for sediment concentration) were further increased when the final roughness index was included in addition to initial roughness index and cumulative kinetic energy in the regressions. This work shows that soil loss and runoff could be predicted from bare soil surface provided the initial roughness and the energy of rainfall is known. However, field verifications of these relationships are needed under different tillage tools and under natural rainfall. Copyright (C) 2002 John Wiley Sons, Ltd