Characterisation of thick liquids using a vibrating transducer

Includes bibliographical referencesThis report describes in detail all the work carried out to reach the main objective of this thesis project, which is to develop a tuning fork into a portable instrument used for the characterisation of thick liquids based on their density and viscosity

Farming systems in Zimbabwe’s smallholder agricultural sector: the case of Gokwe South District

A Working Paper on the smallholder agriculture sector in a rural area of ZimbabweFarming systems in Gokwe South District today are essentially the product of interactions between local indigenous cultivation systems and external interventions. Dryland crop production is the major income generating activity in the area. The major food crops are maize and groundnuts, while cotton and sunflower are the major cash crops. Through the years, changes in bio-physical conditions and population densities have led to a shift from traditional staples such as sorghum and millet to dominant grains, notably, maize. The introduction of a market economy and cash crops in local farming systems has also resulted in local crop production systems moving away from a purely subsistence activity to a partially commercialized industry. Livestock is an integral part of all smallholder farming systems, with cattle constituting the bulk of domesticated animals. Indigenous beef cattle constitute the bulk of cattle kept by individual households. However, farmers' current projections portray a trend of declining indigenous stock, accompanied by an increase in the commercial dairy herd size. The major identified constraints include unfavourable geo-physical conditions, an inadequate, resource base, restricted access, to inputs, labour bottlenecks, pests and diseases, inappropriate post-harvest technology’, poor animal nutrition, poor animal health delivery systems, under-utilised genetic potential, insufficient infrastructure for disposal of marketable produce, and lack of institutional support

Becoming Zimbabwe or becoming Zimbabwean : identity, nationalism and state building in the historical context of Southern Africa.

The lecture explores the processes of identity making and state building in a multi-ethnic and multi-racial society recently emerging from a protracted armed struggle against a racially-ordered settler colonial domination. It explores the extent to which historical factors, such as the nature of the state, the prevailing national political economy and regional and international forces and developments have shaped notions of belonging and citizenship over time and affected state building efforts. The role of the post-colonial state and economy, political developments and the land question in shaping the post-colonial dispensation is also examined. The lecture investigates how Zimbabwe’s lived experience has produced various and competing historical narratives about its past; what factors have contributed to the political economy of historical knowledge production in a colonial and post-colonial setting and how this has further complicated the process of the development of a common identity. It contends that many factors have militated against the development of a common national identity, including, among others, the country’s ethnic diversity, the colonial legacy of racism, autocratic intolerance of political dissent, and a racialised unequal socio-economic regime, the armed conflict that tore the fabric of Zimbabwe’s society for almost two decades and left the races divided, the policy of reconciliation after independence, notwithstanding, the vexatious question of land ownership that remained dangerously unresolved for twenty years, and the problematic role of intellectuals, especially historians, in shaping competing perceptions about the country’s past and present and fuelling difference rather than a sense of common and shared interests.km201

"Zimbabwe is not a South African province" : historicising South Africa's Zimbabwe policy since the 1960s

This paper interrogates analyses of Thabo Mbeki's South Africa's Zimbabwe policy which compare his approach to that of John Vorster's government in the 1970s and decry Mbeki's inability or unwillingness to use its ostensibly considerable hegemonic power to force Robert Mugabe to practise good governance.1 It is argued that just as Vorster used South Africa's dominant influence over Rhodesia to "persuade" Ian Smith to negotiate with the country's African nationalist leaders, the Mbeki administration should have taken a similar line instead of pursuing "quiet diplomacy". The assumption is that little had changed in the relations between the two countries in the meantime and that South Africa continued to have the same level of hegemonic power over Zimbabwe. The paper argues that a more historicised approach shows that the relations between the two countries had changed so dramatically by the 1990s that South Africa no longer wielded compelling power and influence over its northern neighbour. The thirty-year liberation wars in the region and the "debt" that the ANC government owed the region for its support during the struggle, among other factors, meant that the dynamics governing South Africa-Zimbabwe relations were very different.Hierdie artikel bevraagteken analises wat Suid-Afrika se Zimbabwiese beleid in die Mbeki-era vergelyk met dié van John Vorster se regering in die 1970's, en wat Mbeki se onvermoë of onwilligheid betreur om sy land se oënskynlik noemenswaardige hegemoniese mag te gebruik om Robert Mugabe tot 'n verantwoordbare regering te dwing. Daar is aangevoer dat net soos wat Vorster gebruik gemaak het van Suid-Afrika se magsoorwig om Ian Smith te "oorreed" om met sy land se swart nasionalistiese leiers te onderhandel, die Mbeki-regering, in plaas van sy "stille diplomasie", dieselfde roete moes gevolg het. Die aanname is dat daar in die tussentyd weinig verander het wat betref die verhouding tussen die twee lande, en dat Suid-Afrika steeds dieselfde mate van hegemoniese mag oor Zimbabwe gehad het. Hierdie artikel voer aan dat 'n meer historistiese benadering daarop wys dat die verhouding tussen die twee lande teen die 1990's só dramaties verander het dat Suid-Afrika nie meer dieselfde mag en invloed oor sy noordelike buurman kon uitoefen nie. Die streek se dertig jaar-lange vryheidsoorloë en die ANC se "morele skuld" teenoor die streek na dié se steun tydens die vryheidstryd het, tesame met ander faktore, daarop neergekom dat die verhoudingsdinamika tussen Suid-Afrika en Zimbabwe baie anders was.The quote in the title is from BBC News, 5 April 2008, Thabo Mbeki speaking at a Progressive Governance Conference centre left leaders, Watford, England, April 2008.http://www.journals.co.za/ej/ejour_hist.htmlam2016Historical and Heritage Studie

From an industrial powerhouse to a nation of vendors : over two decades of economic decline and deindustrialization in Zimbabwe 1990–2015

From being the second most industrialized country in Sub-Saharan Africa at independence in 1980, Zimbabwe’s economy has declined rapidly to a point where the country ranks among the poorest economic performers in the region. The three pillars which had underpinned the country’s vibrant economy, namely, agriculture, mining and manufacturing, have suffered greatly from poor government policy choices, resulting in the near collapse of each of the sectors and massive unemployment. As a result, an estimated 90% of the Zimbabwean population was unemployed at 2015 and was forced to eke out a living in the informal sector, mostly through vending of second-hand clothes and other basic items. With regard to the manufacturing sector specifically, the sector had all but collapsed by 2015, as companies either folded or relocated to escape the country’s harsh economic climate. This article traces the decline of the Zimbabwean manufacturing sector from 1990 to 2015 and seeks to explain the factors contributing to this decline.http://jds.sagepub.comHistorical and Heritage Studie

Histopathological changes in the reproductive system (ovaries and testes) of Oreochromis mossambicus following exposure to DDT

A b s t r a c t This study assesses the effects of 1,1-bis (4-chlorophenyl)-2,2,2-trichloroethane (DDT) on the reproduction and gonadal histology of adult Mozambique tipalia (Oreochromis mossambicus). The fish were allowed to breed, following exposure to 2 and 5 jig/l of waterborne technical-grade DDT for 40 days. Fertilized eggs were artificially incubated. In the 5 jig/l exposure, posthatch survival was significantly lower, and prevalence of larval skeletal deformities significantly higher, compared to the control (p<0.05). Incomplete axial development was the common gross deformity in posthatch larvae, caused by failure to develop chondroblasts posterior to the buccopharyngeal cavity. There were no significant differences in the gonadosomatic index of exposed and non-exposed male and female adults. The exposure caused increased oocyte atresia in the ovaries and disorganization of seminiferous lobules in the testes of adults. DDT exposure reduced survival and increased deformities in larvae, at levels that did not cause severe histopathological changes to parental gonads

Maternal near miss and maternal death in the Pretoria Academic Complex, South Africa: A population-based study

Background. In order to reduce maternal mortality in South Africa (SA), it is important to understand the process of obstetric care, identify weaknesses within the system, and implement interventions for improving care.Objective. To determine the spectrum of maternal morbidity and mortality in the Pretoria Academic Complex (PAC), SA.Methods. A descriptive population-based study that included all women delivering in the PAC. The World Health Organization definition, criteria and indicators of near miss and maternal death were used to identify women with severe complications in pregnancy. Results. Between 1 August 2013 and 31 July 2014, there were 26 614 deliveries in the PAC. The institutional maternal mortality ratio was 71.4/100 000 live births. The HIV infection rate was 19.9%, and 2.7% of women had unknown HIV status. Of the women, 1 120 (4.2%) developed potentially life-threatening conditions and 136 (0.5%) life-threatening conditions. The mortality index was 14.0% overall, 30.0% for non-pregnancy-related infections, 2.0% for obstetric haemorrhage and 13.6% for hypertension. Of the women with life-threatening conditions, 39.3% were referred from the primary level of care. Vascular, uterine and coagulation dysfunctions were the most frequent organ dysfunctions in women with life-threatening conditions. The perinatal mortality rate was 26.9/1 000 births overall, 23.1/1 000 for women with non-life-threatening conditions, and 198.0/1 000 for women with life-threatening conditions. Conclusion. About one in 20 pregnant women in the PAC had a potentially life-threatening condition; 39.3% of women presented to a primary level facility as an acute emergency and had to be transferred for tertiary care. All healthcare professionals involved in maternity care must have knowledge and skills that equip them to manage obstetric emergencies. Review of the basic antenatal care protocol may be necessary.

Structural, morphological, optical and electrical properties of Schottky diodes based on CBD deposited ZnO : Cu nanorods

Undoped and copper doped zinc oxide (ZnO) nanorods have been synthesized by a simple chemical bath deposition (CBD) method at a temperature of 90 C. Structural, morphological, optical and electrical properties of the synthesized ZnO nanorods were found to be dependent on the Cu doping percentage. X-ray diffraction (XRD) patterns revealed strong diffraction peaks of hexagonal wurtzite of ZnO, and no impurity phases from metallic zinc or copper. Scanning electron microscopy (SEM) images showed changes in diameter and shape of nanorods, where by those doped with 2 at.% and 3 at.% aggregated and became compact. Selected area electron diffraction (SAED) patterns indicates high quality, single crystalline wurtzite structure ZnO and intensities of bright spots varied with copper doping concentration. UVevisible absorption peaks of ZnO red shifted with increasing copper doping concentration. Raman studies demonstrated among others, strong and sharp E2 (low) and E2 (high) optical phonon peaks confirming crystal structure of ZnO. Current-voltage measurements based on the gold/ZnO nanorods/ITO showed good rectifying behavior of the Schottky diode. The predicted Schottky barrier height of 0.60 eV was obtained which is not far from the theoretical Schottky-Mott value of 0.80 eVThe University of Pretoria and National Research Foundation (NRF), South Africa, Grant No: 91550 and 94166.http:// www.elsevier.com/locate/superlattices2018-07-31hb2017Physic

Mortality under early access to antiretroviral therapy vs Eswatini’s national standard of care : the MaxART clustered randomized stepped‐wedge trial

Objectives Current WHO guidelines recommend the treatment of all HIV-infected individuals with antiretroviral therapy (ART) to improve survival and quality of life, and decrease infection of others. MaxART is the first implementation trial of this strategy embedded within a government-managed health system, and assesses mortality as a secondary outcome. Because primary findings strongly supported scale-up of the 'treat all' strategy (hereafter Treat All), this analysis examines mortality as an additional indicator of its impact. Methods MaxART was conducted in 14 Eswatinian health clinics through a clinic-based stepped-wedge design, by transitioning clinics from then-national standard of care (SoC) to the Treat All intervention. All-cause, disease-related, and HIV-related mortality were analysed using the Cox proportional hazards model, censoring SoC participants at clinic transition. Median follow-up time among study participants was 292 days. There were 36/2034 deaths in SoC (1.77%) and 49/1371 deaths in Treat All (3.57%). Results Between September 2014 and August 2017, 3405 participants were enrolled. In SoC and Treat All interventions, respectively, the multivariable-adjusted 12-month all-cause mortality rates were 1.42% [95% confidence interval (CI): 0.66-2.17] and 1.60% (95% CI: 0.78-2.40), disease-related mortality rates were 1.02% (95% CI: 0.40-1.64) and 1.10% (95% CI: 0.46-1.73), and HIV-related mortality rates were 1.03% (95% CI: 0.40-1.65) and 0.99% (95% CI: 0.40-1.58). Treat All had no impact on all-cause [hazard ratio (HR) = 1.12, 95% CI: 0.58-2.18, P = 0.73], disease-related (HR = 1.04, 95% CI: 0.52-2.11, P = 0.90), or HIV-related mortality (HR = 0.93, 95% CI: 0.46-1.87, P = 0.83). Conclusion There was no immediate benefit of the Treat All strategy on mortality, nor evidence of harm. Longer follow-up of participants is needed to establish long-term consequences