University of Zimbabwe

About: University of Zimbabwe is a education organization based out in Harare, Harare, Zimbabwe. It is known for research contribution in the topics: Population & Acquired immunodeficiency syndrome (AIDS). The organization has 4378 authors who have published 6800 publications receiving 160720 citations. The organization is also known as: UZ & University College of Rhodesia and Nyasaland.

Risk factors for pre-eclampsia among Zimbabwean women: maternal arm circumference and other anthropometric measures of obesity.

Abstract: Maternal pre-pregnancy obesity is a risk factor for preeclampsia (proteinuric hypertension in pregnancy) among North American and European women. We studied the relationship between maternal obesity and risk of pre-eclampsia among Zimbabwean women. A case-control study was conducted at Harare Maternity Hospital Harare Zimbabwe between June 1995 and April 1996. Study participants were 144 women with pre-eclampsia and 194 normotensive women serving as controls. Maternal weight height and mid-arm circumference were measured and recorded during study participants postpartum hospital admission. Maternal mid-arm circumference considered to be relatively stable during pregnancy among women of developing countries was used as the primary indicator of maternal pre-pregnancy obesity. Logistic regression procedures were used to estimate odds ratios and 95% confidence intervals. There were linear trends in risk of preeclampsia with increasing mid-arm circumference increasing weight and increasing body mass index. After adjusting for potential confounding factors women in the highest quintile for mid-arm circumference (28-39 cm) were 4.4 times more likely to have had their pregnancy complicated by pre-eclampsia than women in the lowest quintile (21-23 cm). Odds ratios of similar magnitude were observed for the other anthropometric measures. To our knowledge this is the first study to demonstrate a positive association between maternal obesity and pre-eclampsia risk in a black African population. Biological mechanisms thought to explain this relatively consistent epidemiological finding include endothelial cell injury possibly resulting from hyperlipidaemia. (authors)

Nitrogen mineralization and maize yields following application of tree prunings to a sandy soil in Zimbabwe

Abstract: Despite the promotion of prunings as sources of nitrogen for crops, lack of synchronization between N mineralization from prunings and plant uptake remains a major limitation to the impact of prunings on crop yields. A laboratory and a field experiment were therefore carried out to determine the mineralization patterns of selected prunings and assess the potential that exists to improve synchrony by mixing prunings of different quality. The laboratory incubation experiment was conducted for 84 days to determine the C and N release patterns of prunings of different quality and the manipulation of the C and N mineralization trends by mixing prunings of different quality. High quality prunings were considered to be those with high CO2 evolution rates and mineralize N rapidly. The % C and % N released in 84 days were highest for the high quality prunings of Tithonia diversifolia (70% and 30% respectively) and least for the low quality prunings of Flemingia macrophylla (25% and –5% respectively). The medium quality prunings of Acacia angustissima and Calliandra calothyrsus had similar proportions of released C and N (about 40% C and 10% N). Different mixtures of T. diversifolia with other species showed contrasting influence on C release and N mineralization. Most mixtures released less C than that predicted, but in contrast most mixtures released N at a rate either matching or above the predicted. The % N released was strongly correlated with the polyphenol protein binding capacity (r2 = 0.53) and also with the % C released (r2 = 0.62). The field experiment was done for two cropping seasons to determine the effects of the prunings of these species and their mixtures on maize grain yield. The prunings were added at 5 t ha−1 and incorporated into the top 15 cm by hand hoeing in the first season and their residual effects were monitored in the second season. Medium and low quality prunings produced significantly (p < 0.05) higher maize grain yields in the first season ranging between 2.4 t ha−1 and 3.4 t ha−1 compared with T. diversifolia which produced 1.7 t ha−1. This suggested better synchrony in N release and uptake by maize with medium and low quality prunings compared with high quality prunings. The only mixture that indicated improved synchrony was the mixture of T. diversifolia and C. calothyrsus. This study showed that mixing prunings of different quality produce different patterns of N mineralization, some of which were unexpected and had a potential for improving N synchrony.

Gender and Economic Empowerment in Africa: Evidence and Policy

Abstract: Gender inequality continues to be a major challenge in Africa. Although progress has been made by ratification of international and regional conventions and commitments by African countries, gender inequality is still prevalent in all sectors of the economy, including the labour market. The majority of women are working in the informal sector or on small pieces of land and are engaged in care work, where the work is invisible and unpaid. Women's labour force participation rates are lower than those for men. More men than women work in the formal sector where the work is paid and supported by all the national policies. Women contribute immensely to the country's economy. Despite their contribution, gender inequality still prevails. Women have limited access to credit, land, agricultural inputs, equipment and extension services, and markets for their produce. They spend more time in care and domestic work than men. Some of the inequities are embedded in the deep-rooted cultural norms and beliefs in the societies. These inequalities can only be addressed by removal of policies that reinforce gender inequalities as well as formulating and enforcing laws that seek to improve women's economic empowerment. Initiatives identified to improve women's economic empowerment include revision of regulations to increase women's participation in the labour market, skills training, policy reforms on regulations that hinder women's empowerment, setting up of micro-credit schemes, use of technology to access markets such as mobile phones to release women's time in caring and domestic work, fostering of partnership by providing funding to women, cash transfers and welfare fund, subsidised or publicly provided child care and skill training as well as improving infrastructure services such as water and electricity.

Sewage discharges and nutrient levels in Marimba River, Zimbabwe

Abstract: Population distribution, land-use, industrial activity, urban agricultural activities, and pollution control strategies in Harare, Zimbabwe, have all changed significantly since independence in 1980. The effects of these changes on water quality and the consequences on human and ecological health are of major economic and social importance. This study looked at pollution in the Marimba River, one of the major inflow rivers into the Lake Chivero, Harare city’s main water supply source. The river was characterised using standard physical and chemical methods to assess water quality from June 2000 to December 2001. Monthly sampling results indicated high pollution levels, especially nutrients. Nitrogen values averaged 13.5 ±2.0 mg·l -1 as N, and phosphorus 2.6 ±0.6 mg·l -1 as P at the river’s discharge point into Lake Chivero. The high nutrient values, exceeding acceptable limits, are indicative of industrial, agricultural, and sewage discharges upstream. The gross river pollution levels are detrimental to the downstream Lake Chivero. It was concluded that although there are other significant incidental sources of nutrient pollution in Marimba River, sewage effluent is by far the major polluter. It was established that pond overflow from Crowborough Sewage Treatment Works is the major source of sewage inflows and treating this to tertiary standard would result in 46% and 35% reductions respectively for total nitrogen and total phosphorus loads in the Marimba River

Age of the Batoka basalts, northern Zimbabwe, and the duration of Karoo Large Igneous Province magmatism

Abstract: [1] Analysis of the Batoka Basalts exposed in the Zambezi Gorge some 40 km east of Victoria Falls characterizes them as high Fe, moderately high Ti, and low K, P, and Zr tholeiites. The 40Ar-39Ar age determinations are tightly clustered at 180–179 Ma. All of the lavas that were sampled have normal paleomagnetic polarity, and the corresponding pole position is 63.9°N, 260.6°E, A95 = 14.9°. In South Africa, Lesotho, and Namibia the vast majority of Karoo basalts were extruded at 183 ± 1 Ma with some as young as 179 Ma [Duncan et al., 1997]. Paleomagnetic and geochemical correlation of the ∼179 Ma rocks between Zimbabwe and Lebombo supports the conclusion that the age difference is real and hence confirms the estimate of ∼5 Myr for the duration of emplacement of the Karoo Large Igneous Province.