Showing papers by "University of Zimbabwe published in 2002"
TL;DR: The substantial age difference between female and male sexual partners in Manicaland is the major behavioural determinant of the more rapid rise in HIV prevalence in young women than in men.
644 citations
TL;DR: In this article, the authors discuss a set of six constraints limiting the usefulness of forecasts: credibility, legitimacy, scale, cognitive capacity, procedural and institutional barriers, and available choices.
Abstract: For the last decade, climate scientists have improved their skill at predicting seasonal rainfall patterns in many parts of the world based on observations of sea surface temperatures. Making forecasts useful to decision-makers, especially subsistence farmers in developing countries, remains a significant challenge. In this paper, we discuss a set of six constraints limiting the usefulness of forecasts: credibility, legitimacy, scale, cognitive capacity, procedural and institutional barriers, and available choices. We identify how these constraints have in fact limited forecast use so far, and propose means of overcoming them. We then discuss a pilot project in Zimbabwe, where we test our proposals. Drawing from two years’ observation, we offer lessons to guide future efforts at effective forecast communication.
345 citations
TL;DR: The decolorization efficiency of T. modesta laccase was improved remarkably in the presence of mediators like 1-hydroxybenzotriazole and 2-methoxyphenothiazine, and was selected for further studies.
305 citations
TL;DR: The role that three major infectious diseases--malaria, sexually transmitted diseases (STDs), and tuberculosis--have had in the HIV-1 epidemic is described.
208 citations
TL;DR: The authors reviewed the literature on the vegetation of the Kalahari and described the vegetation structure and composition at 11 new sites and found that there is a clear gradient in woody plant biomass (as indexed by basal area) from south to north.
Abstract: The Kalahari sand sheet occupies 2.5 million ha in southern Africa. It is an area with relatively similar deep aeolian soils, and a strong south to north gradient in rainfall, from 200 to 1000 mm mean annual precipitation (MAP) in the region studied. This provides an excellent basis for gradient studies at the subcontinental scale. This paper briefly reviews the literature on the vegetation of the Kalahari and describes the vegetation structure and composition at 11 new sites. There is a clear gradient in woody plant biomass (as indexed by basal area) from south to north. Above the minimum level of 200 mm MAP, the woody basal area increases at a rate of ca. 2.5 m2.ha−1 per 100 mm MAP. Mean maximum tree height also increases along the gradient, reaching 20 m at ca. 800 mm MAP. The number of species to contribute > 95% of the woody basal area increases from one at 200 mm to 16 at 1000 mm MAP. Members of the Mimosaceae (mainly Acacia) dominate the tree layer up to 400 mm MAP. They are replaced by ei...
198 citations
TL;DR: In this preliminary study, the novel 100-kDa-like-protein gene nested PCR revealed a specificity of 100% without requiring sequencing, which was necessary for identification of the 18S ribosomal DNA nested PCR products in order to avoid a high rate of false-positive results.
Abstract: In order to evaluate the diagnostic relevance of two nested PCR assays for diagnosis of histoplasmosis in clinical specimens, 100 paraffin-embedded biopsy specimens were examined. Upon microscopy of tissue, 50 biopsy specimens were histoplasma positive and 50 were negative. Due to destruction by formalin fixation, successful extraction of amplifiable human DNA was limited to 29 and 33 samples, respectively. A product of the Histoplasma capsulatum nested PCR assay targeting the gene encoding the unique fungal 100-kDa-like protein was detected in 20 histopathologically positive biopsy specimens but in none of the microscopically negative samples. Sequencing revealed that all 20 products of 210 bp were identical to the sequence of H. capsulatum in the GenBank database. In contrast, the nested PCR assay targeting the fungal 18S rRNA genes amplified products in 26 histopathologically positive but also in 18 microscopically negative biopsy specimens. However, sequencing revealed that only 20 of these 44 PCR products (231 bp) were identical to the sequence of H. capsulatum. The remaining 24 sequences were homologous to those of several Euascomycetes. These PCR products were detected only in tissues possibly colonized by nonpathogenic fungi, possibly causing these nonspecific amplifications. The detection limit of both H. capsulatum nested PCR assays was 1 to 5 fungal cells per sample. The two assays were similarly sensitive in identifying H. capsulatum. In this preliminary study, the novel 100-kDa-like-protein gene nested PCR revealed a specificity of 100% without requiring sequencing, which was necessary for identification of the 18S ribosomal DNA nested PCR products in order to avoid a high rate of false-positive results.
183 citations
TL;DR: HIV testing and a behavioral survey were conducted with a cross-sectional sample of 324 men recruited at beerhalls in Harare, Zimbabwe to examine the relationship among alcohol use, high-risk sexual behavior, and HIV infection among male beerhall patrons and to evaluate the feasibility of usingBeerhalls as venues for male-centered HIV prevention activities.
Abstract: HIV testing and a behavioral survey were conducted with a cross-sectional sample of 324 men recruited at beerhalls in Harare, Zimbabwe, to examine the relationship among alcohol use, high-risk sexual behavior, and HIV infection among male beerhall patrons and to evaluate the feasibility of using beerhalls as venues for male-centered HIV prevention activities. Recent HIV seroconversions were identified using the less-sensitive enzyme immunoassay. HIV education activities were provided inside beerhalls and qualitative methods were used to assess the acceptability of conducting HIV prevention activities and research at beerhalls. The prevalence of HIV infection was 30%; the prevalence of recent seroconversion was 3.4%. Having sex while intoxicated in the previous 6 months was reported by 31% of men and was strongly associated with recent HIV seroconversion as well as unprotected sex with casual partners and paying for sex. Acceptability of prevention and research activities was high among beerhall patrons, managers, and owners. Beerhalls present an environment associated with high-risk sexual behavior and concomitantly high rates of HIV seroconversion. Beerhalls are appropriate and feasible venues for delivering HIV prevention programs targeted at men in many regions of sub-Saharan Africa and the world.
144 citations
TL;DR: The effects of the carbon and nitrogen sources, initial pH and incubation temperature on laccase production by Trametes modesta were evaluated using the one-factor-at-a-time method, resulting in a four-fold increase of the lAccase activity to 178 nkat ml(-1).
144 citations
TL;DR: In this article, U-Pb dating of zircon and rutile from bronzitites of the P1 pyroxenite layer of the Great Dyke precisely constrains the crystallization age of this part of the intrusion to 2575.4±0.7 Ma.
128 citations
TL;DR: Results offer compelling evidence that ward-based contraceptive services provided to women treated for incomplete abortion can significantly reduce subsequent unplanned pregnancies and suggest that postabortion family planning services can reduce the incidence of repeat abortion.
Abstract: In many countries, women treated for complications from spontaneous or unsafely induced abortion lack access to contraceptive services. As a result, many of them soon have a subsequent unplanned pregnancy or a repeat abortion, placing their health at increased risk. This report presents the results of a prospective intervention study on postabortion family planning conducted in the two largest public hospitals in Zimbabwe. Women at Harare Central Hospital, in the capital, received a postabortion family planning intervention, and Mpilo Central Hospital, in Bulawayo, served as the control site. The study cohort was 982 women, 527 of whom were followed for a 12-month period. During the follow-up period, significantly more women used highly effective methods of contraception, significantly fewer unplanned pregnancies occurred, and fewer repeat abortions were performed at the intervention site than at the control site. These results offer compelling evidence that ward-based contraceptive services provided to women treated for incomplete abortion can significantly reduce subsequent unplanned pregnancies. The results also suggest that postabortion family planning services can reduce the incidence of repeat abortion.
121 citations
TL;DR: It is concluded that, in soil with sufficient and relatively uniform background 15 N abundance and using appropriate, or a range of, non-fixing reference plants, the natural δ 15N abundance method is a useful tool for estimating the amount of N derived from N 2 -fixation by field grown herbaceous and woody legumes.
Abstract: Short-term legume–cereal rotation systems (referred to as improved fallows) with N 2 fixing leguminous species are being actively promoted to improve soil fertility in fallowed fields of smallholder farms in many parts of the tropics. Few estimates of N 2 -fixation in deep-rooted woody fallow species are available due to methodological difficulties. We evaluated and developed the natural δ 15 N abundance method for assessing N 2 -fixation in herbaceous and woody legumes on a Kandiudalfic Eutrudox in western Kenya by (i) assessing isotopic discrimination during N 2 -fixation and translocation, (ii) measuring variability of 15 N with depth, (iii) comparing with an independent method (ureide assay) and (iv) using several non-fixing reference plants. Most tested tree/shrub legumes showed no 15 N discrimination during N 2 -fixation (i.e. whole plant δ 15 N was close to 0‰). Significant 15 N isotopic discrimination occurred during translocation of fixed N, which resulted in 15 N depletion in shoots (up to −1.76‰ in Sesbania sesban ) compared with roots and nodules which were 15 N enriched. Soils were highly enriched in 15 N (8.2–10.8‰) with little variation with depth to 2 m. δ 15 N signatures of plant available N measured using non-fixing reference plants were lower than those of total soil N. δ 15 N of the non-fixing reference species maize, Lantana camara and Tithonia diversifolia varied by 2.0‰ and resulted in corresponding variation of N 2 -fixation estimates for respective species. 15 N based estimates of N 2 -fixation of pigeonpea and siratro were linearly related with those obtained using the ureide method ( R 2 =0.80, slope=0.82) and confirmed the utility of the 15 N natural abundance method. Field observations showed that under non-PK limiting growth conditions, the proportion of N 2 fixed ranged 75–83, 63–74, 55–67, 46–59, 36–54, 35–50, and 36–51% for Crotalaria grahamiana , Tephrosia vogelii , pigeonpea ( Cajanus cajan ), S. sesban , Calliandra calothyrsus , siratro ( Macroptilium atropurpureum ) and groundnut ( Arachis hypogaea ). This resulted in average amounts of N 2 fixed of 142, 100, 91, 52, 24, 64 and 8 kg N ha −1 , respectively, 9 months after planting. The amount of soil derived N ranged between 31 and 57 kg N ha −1 in woody species. The net N balance of woody fallows (after adjusting for N export in wood) was highest in Crotalaria due to high N 2 -fixation and small amount of N exported in wood. Overall, partial N balances indicated that additional N derived from N 2 -fixation constituted a major component of recyclable N of the system. We conclude that, in soil with sufficient and relatively uniform background 15 N abundance and using appropriate, or a range of, non-fixing reference plants, the natural δ 15 N abundance method is a useful tool for estimating the amount of N derived from N 2 -fixation by field grown herbaceous and woody legumes.
TL;DR: A cross-sectional study determined the prevalence of ecto-, endo- and haemoparasites in free-range chickens from the Goromonzi District, Zimbabwe, and identified the most prevalent nematodes and cestodes.
TL;DR: In this paper, changes in miombo woodland cover in and around Sengwa Wildlife Research Area (SWRA) between 1958 and 1996 were quantified by analyzing aerial photographs, suggesting that loss of woody cover was mainly due to elephants.
Abstract: One of the consequences of impacts of elephants and fire on woodlands is a change in woody cover, which often results in major challenges for wildlife managers. Changes in miombo woodland cover in and around Sengwa Wildlife Research Area (SWRA) between 1958 and 1996 were quantified by analyzing aerial photographs. Woody cover in SWRA decreazed from 95.2% in 1958 to 68.2% in 1996, with a lowest mean of 62.9% in 1983. The annual absolute rate of woody cover change in SWRA increazed from −1.1% per annum between 1958 and 1964 to a recovery of 1.6% per annum between 1993 and 1996, while the annual relative rate increazed from −1.1% per annum between 1958 and 1964 to 3.3% per annum between 1993 and 1996. There was a strong negative correlation between elephant densities and woody cover in SWRA, suggesting that loss of woody cover was mainly due to elephants. Woodland recovery after 1983 was due to reductions in elephant populations through legal and illegal off-take and reductions in fire frequency. Surrounding areas experienced less woody cover losses than SWRA, mainly due to tree removal by locals whose densities increazed after the eradication of tsetse fly in the 1970s.
Resume
Une des consequences de l'impact des elephants et des feux sur les forets s'exprime par un changement du couvert ligneux qui pose souvent de fameux defis pour les gestionnaires de la faune. Les changements du couvert forestier a Miombo, qui sont survenus a l'interieur et aux alentours de l'Aire de Recherche sur la Faune de Sengwa (SWRA) entre 1956 et 1996, ont ete quantifies grâce a l'analyse de photos aeriennes. Le couvert forestier de la SWRA a diminue de 95.2% en 1958 a 68.2% en 1996, la moyenne la plus basse etant observee en 1983, avec 62.9%. Le taux annuel absolu de changement du couvert forestier dans la SWRA est passe de – 1.1% par an entre 1958 et 1964 a une restauration de 1.6% par an entre 1993 et 1996, tandis que le taux annuel relatif augmentait de – 1.1% par an entre 1958 et 1964 a 3.3% par an entre 1993 et 1996. Il existait une forte correlation negative entre la densite des elephants et le couvert forestier de la SWRA, ce qui laisse supposer que la perte de couvert forestier etait due principalement aux elephants. La restauration de la foret apres 1983 etait due a des reductions des populations d'elephants suite a des prelevements, legaux ou non, et a une baisse de la frequence des feux. Les zones adjacentes ont subi de moins fortes pertes du couvert forestier que la SWRA, et celles-ci etaient principalement dues a des coupes faites par les locaux dont la densite a augmente suite a l'eradication de la mouche tse-tse dans les annees 1970.
TL;DR: In this paper, the role of learning tools in enhancing the capacity of resource users to innovate and manage their land in an adaptive manner is discussed based on experiences in Zimbabwe, core elements of a learning process approach to innovation in natural resource management using "learning tools" is described and analysed.
TL;DR: Zimbabwe attained independence in 1980, and there were high hopes expressed for Zimbabwe's political and economic future as mentioned in this paper, and it appeared to live up to some of these expectations, especially in its first decade of independence.
Abstract: When it attained its independence in 1980, there were high hopes expressed for Zimbabwe's political and economic future. It was amongst the top four more industrialized countries in Sub‐Saharan Africa; it possessed a more diversified economy than most countries; and it had a better human resource base than most; and it had a middle‐income status. Comparatively speaking, therefore, Zimbabwe had better prospects of making a head start in economic and political development than most countries on the continent. For some years, especially in its first decade of independence, it appeared to live up to some of these expectations. There were considerable investments in social development (characterised by a massive expansion in the education and social sectors); the economy itself grew; and it quickly became the regional breadbasket. Furthermore, the country was an oasis of stability in a region then mired in turmoil from Angola to Mozambique, and in liberation struggles from Namibia to South Africa.
TL;DR: Three specific constraints on child protection are examined in this article, namely poverty, HIV/AIDS infection, and war, which use their experience in Africa to raise issues of resilience and adaptation, dangers to child protection programs, and possible solutions.
TL;DR: In this paper, a study was carried out at Firle farm, owned by the Municipality of Harare, to assess heavy metal loading on a sandy soil and uptake of the metals by pasture grass consisting of a mixture of Cynodon nlemfuensis (star grass) and Pennisetum clandestinum Chiov (kikuyu grass).
Abstract: Although sewage effluent and sludge provides nutrients for plant growth, its continual use over extended periods can result in the accumulation of heavy metals in soils and in grass to levels that are detrimental to the food chain. This study was carried in 2001 out at Firle farm, owned by the Municipality of Harare, to assess heavy metal loading on a sandy soil and uptake of the metals by pasture grass consisting of a mixture of Cynodon nlemfuensis (star grass) and Pennisetum clandestinum Chiov (kikuyu grass) following sewage effluent and sludge application for 29 years. Firle Farm receives treated effluent and sludge emanating from domestic and industrial sources. Soil and grass samples were taken from the study area, consisting of 3 ha of non-irrigated area (control) and 1.3 ha of irrigated area. Both the soil and grass samples were tested for Cu, Zn, Ni and Pb using atomic absorption spectrophotometry. Sewage sludge addition resulted in high levels of soil pollution, especially in the 20 cm horizon, in the irrigated area when compared to the control. Grasses took up moderate levels of Cu and Zn, and limited levels of Pb. Nickel was not detectable in grasses despite high levels in the irrigated soil. Copper uptake was several times higher than the suggested potentially toxic level of 12 mg/kg [Soil Science Society of America, Micronutrients in agriculture, second ed., Wisconsin, USA, 1991]. Lead uptake averaged 1.0 mg/kg, which was below 10 mg/kg the suggested limit for agronomic crops [E.M. Seaker, Zinc, copper, cadmium and lead in minespoil, water and plants from reclaimed mine land amended with sewage sludge, 1991]. Cu and Zn showed relatively higher mobility down the soil profile than Ni and Pb. Even then, the concentrations in the lower soil layers were very small, suggesting that the metals were unlikely to contaminate groundwater. There was no direct correlation between metal levels in soils and grasses. It was postulated that it is the bio-available metal fraction in the soil that is correlated to plant uptake. The grasses appeared healthy even though they contained moderately high levels of Zn and Cu. This raises the possibility of beef animals grazing on “healthy” looking grass that has very high concentrations of heavy metals. The fact that the total metal concentrations in the experimental soil were very high but did not cause any toxicity symptoms to the grass suggested that the limit soil concentration do not necessarily imply toxicity to all plants. However, limit concentrations are set not only for plant growth, but also for the protection of soil microorganisms and the latter are more sensitive to heavy metal pollution.
TL;DR: In the tropical upland regions of the world, the world's highest population growth rates and a preponderance of soils less suitable for agriculture have been observed as discussed by the authors, where nitrogen deficiency is almost universal, while acid infertility and the related problem of P deficiency affect more than 40% of tropical soils.
Abstract: Tropical upland regions have both the world's highest population growth rates and a preponderance of soils less suitable for agriculture. Nitrogen deficiency is almost universal, while acid infertility and the related problem of P deficiency affect more than 40% of tropical soils. Nutrient depletion, as opposed to inherent infertility, affects large areas due to continuous cropping with few inputs. Nitrogen management requires a continual supply of N that can be achieved through fertilization, green manuring, legume rotations or leguminous tree-shrub fallows. Rotations and fallows usually require foregoing one or more staple crop harvests, which is not feasible for smallholder farmers in land-limited areas. In such areas there are few options for farmers except mineral N fertilizers. Phosphorus availability can be built up in soils, but to achieve this, external inputs of inorganic P are essential. Use of P-efficient crops, or mobilisation of soil organic P by various means, are temporary solutions since they involve only offtake with no addition. Phosphorus additions may be either as soluble processed fertilizers or indigenous phosphate rocks (PRs). Most tropical PR deposits are unreactive and require processing before use. Some lower-cost options include partial acidulation, blending with soluble P sources or microbial solubilization. The relevance of microbial solubilization in particular requires testing at larger scale. There are no magic solutions to soil nutrient deficiencies or toxicities; to maintain productivity mineral fertilizers are necessary. They should be used in judicious amounts and coupled with improved organic matter management.
TL;DR: Polynomial regression analysis was used to determine the relationship between maize cob levels with digestibility of nutrients, feed intake, average daily gain (ADG) and feed conversion ratio (FCR) in Zimbabwean indigenous Mukota and exotic Large White pigs fed high fibre diets.
TL;DR: The increase in number of microorganisms in the milk was correlated with factors which would increase delivery time and the microbiological quality of milk at the farm and on delivery at three smallholder dairies in Zimbabwe were studied.
TL;DR: A cycle of HIV transmission that involves older men, younger women, and ultimately the steady partners of both is corroborated, suggesting nightclubs and other drinking establishments catering to youth can provide opportunities for preventing HIV transmission through stuctural interventions or targeted outreach education.
Abstract: We conducted a quantitative and qualitative study of alcohol use and high-risk sexual behavior among adolescents and young adults of age 15–21 years in Harare, Zimbabwe. Methods included a cross-sectional survey of youth sampled at nightclubs and bottle stores informed by participant observation, key informant interviews, and focus group discussions. Findings corroborated a cycle of HIV transmission that involves older men, younger women, and ultimately the steady partners of both. Nightclubs and other drinking establishments catering to youth can provide opportunities for preventing HIV transmission through stuctural interventions or targeted outreach education.
TL;DR: The ubiquitous expression of GSTs in different malignancies suggests that the addition of nontoxic reversing agents such as antimalarials could enhance the efficacy of a variety of alkylating agents.
Abstract: A strategy to overcome multidrug resistance in cancer cells involves treatment with a combination of the antineoplastic agent and a chemomodulator that inhibits the activity of the resistance-causing protein. The aim of our study was to investigate the effects of antimalarial drugs on human recombinant glutathione S-transferase (GSTs) activity in the context of searching for effective and clinically acceptable inhibitors of these enzymes. Human recombinant GSTs heterologously expressed in Escherichia coli were used for inhibition studies. GST A1-1 activity was inhibited by artemisinin with an IC(50) of 6 microM, whilst GST M1-1 was inhibited by quinidine and its diastereoisomer quinine with IC(50)s of 12 microM and 17 microM, respectively. GST M3-3 was inhibited by tetracycline only with an IC(50) of 47 microM. GST P1-1 was the most susceptible enzyme to inhibition by antimalarials with IC(50) values of 1, 2, 1, 4, and 13 microM for pyrimethamine, artemisinin, quinidine, quinine and tetracycline, respectively. The IC(50) values obtained for artemisinin, quinine, quinidine and tetracycline are below peak plasma concentrations obtained during therapy of malaria with these drugs. It seems likely, therefore, that GSTs may be inhibited in vivo at doses normally used in clinical practice. Using the substrate ethacrynic acid, a diuretic drug also used as a modulator to overcome drug resistance in tumour cells, GST P1-1 activity was inhibited by tetracycline, quinine, pyrimethamine and quinidine with IC(50) values of 18, 27, 45 and 70 microM, respectively. The ubiquitous expression of GSTs in different malignancies suggests that the addition of nontoxic reversing agents such as antimalarials could enhance the efficacy of a variety of alkylating agents.
TL;DR: Cryptococcal meningoencephalitis in African children presents acutely or subacutely, can have a fulminant picture and is consistent with progressive meningoencesphalitis.
Abstract: Background. The number of children with AIDS in Africa is high. Such children may be at risk for cryptococcal meningoencephalitis but data are scarce regarding this disease in our population. Methods. We examined records of HIV-infected children (<16 years) diagnosed with cryptococcal meningoencephalitis in Harare Zimbabwe between 1995 and 2000. To elucidate features unique to pediatric disease the children were compared with adult patients with HIV-associated cryptococcal meningoencephalitis. Results. Thirteen children presented to our institution with headache (85%) nuchal rigidity (69%) vomiting (46%) impaired mental status (38%) convulsions (38%) and focal neurologic signs (23%). The mean duration of symptoms before diagnosis was 9 days. Cerebrospinal fluid examination revealed normal white blood cell counts in 64% protein value in 67% and glucose concentration in 57% of patients. Children were more likely than adults to have seizures (38% vs. 11% P = 0.02) and normal cerebrospinal fluid protein (67% vs. 10% P < 0.01). The in-hospital mortality was 43%. Convulsions (P = 0.05) and impaired mental status (P < 0.01) were associated with increased mortality Conclusions. Cryptococcal meningoencephalitis in African children presents acutely or subacutely can have a fulminant picture and is consistent with progressive meningoencephalitis. (authors)
TL;DR: Transferrin concentration and total iron binding capacity (TIBC) are currently used to assess iron status as discussed by the authors, however, due to the high correlation between TIBC and transferrin, conversion factors between the two analytes found in literature show large differences.
Abstract: Transferrin concentration and total iron binding capacity (TIBC) are currently used to assess iron status. Although correlation between TIBC and transferrin is generally considered as good, conversion factors between the two analytes found in literature show large differences. Although the price per test is lower for TIBC, there are a number of analytical advantages of serum transferrin. Due to binding of iron to other plasma proteins (mainly albumin), TIBC methods generally overestimate the iron binding capacity of transferrin. Moreover, no generic reference values are available for TIBC. In contrast to TIBC, internationally accepted interim reference ranges are available for serum transferrin. The introduction of the international CRM 470 protein standard material has lead to a significant reduction in interlaboratory variation for transferring measurements. In view of these observations, determination of transferrin concentration, rather than TIBC, is recommended. However, in non-European populations characterized by a marked genetic variation in transferrin (TF BC and TF CD variants), in certain cases, immunochemical determination of transferrin may lead to errors. In these populations, TIBC measurements may be preferred.
TL;DR: In this article, the authors present data on the water supply situation in the City of Mutare, Zimbabwe, and attempt to identify and quantify water losses in the system, which would involve relatively modest resources.
Abstract: The question posed in this paper is: why is the concept of water demand management rarely implemented on the ground? To answer this question the paper presents data on the water supply situation in the City of Mutare, Zimbabwe. It describes Mutare’s water infrastructure, the patterns of water use during the period 1980–2000; and our attempts to identify and quantify water losses in the system. Suggestions are made how these losses can be reduced, which would involve relatively modest resources. The question is then asked why these measures have not yet been taken. The paper contrasts this to the Pungwe scheme, a new water supply project of huge proportions which was conceived and implemented fairly quickly. The fact that water is a vital yet finite and fugitive resource explains why powerful water coalitions may emerge between engineers, financiers and politicians. It is the experience from Mutare and elsewhere that such coalitions tend to favour supply-side solutions to water scarcity. For effective adoption of water demand management it is essential to acknowledge this political dimension. As a strategy it is suggested that: (a) stakeholders should be better informed about alternative solutions to water problems; (b) a new generation of engineers trained in integrated water resources management is needed with the skills to carefully study the problem definition before rushing to solutions; and (c) financiers should be made aware of the relevance and economic rationale of demand management solutions.
TL;DR: The experiences of African communities are significantly underrepresented in the current psychological literature as compared to those of Western European and North American communities as mentioned in this paper, and professional psychology in sub-Saharan African is either nonexistent or strongly modeled after practices in North America and Western Europe.
Abstract: The experiences of African communities are significantly underrepresented in the current psychological literature as compared to those of Western European and North American communities. Professional psychology in sub-Saharan African is either nonexistent or strongly modeled after practices in North America and Western Europe. The modeling of psychology in sub-Saharan Africa on the North American and Western European experience is a result of the more extensive marketing of the Western cultural heritage around the globe by national governments, education institutions and international aid agencies vis a vis the marketing of alternative cultural heritages. It is also reflective of the historically unequal intercultural exchanges between Western and African cultural heritages and in favour of the former. A greater representation of the African experience in the psychological literature could add to the richness and global relevance of psychology. Les experiences des communautes africaines sont significative...
TL;DR: It is concluded here that CYP1A1 Val462 polymorphism is very rare among Africans, and there are no differences in frequencies of the variant alleles for CYP 1A1, GSTM 1, GSTT1 and GSTP1 in the three African populations.
Abstract: The co-ordinate expression and regulation of the drug metabolising enzymes, cytochrome P4501A1 (CYPlAl) and glutathione transferases (GSTM1, GSTT1 and GSTP1), and their metabolic balance in the cells of target organs may determine whether exposure to carcinogens results in cancer. Besides showing variability in activity due to induction and inhibition, these enzymes also exhibit genetic polymorphism that alter enzyme levels and activity. We determined frequencies of common allelic variants of CYP1A1 and glutathione (M1, T1 and P1) among Tanzanians, South African Venda and Zimbabweans using PCR/restriction fragment length polymorphism techniques. The CYP1A1 Val462 mutant variant was found at a frequency of 1.3% among 114 subjects. The GSTM1*0 genotype was found at a frequency of 29% and 33% among Tanzanian psychiatric patients and healthy volunteers, respectively. Similarly, the GSTT1*0 polymorphism was present with a frequency of 25% in both the psychiatric patients and healthy controls. The frequency of GSTP1 Val105 variant was 16%, 12% and 21% among Tanzanians, South African Venda and Zimbabweans, respectively. We conclude here that CYP1A1 Val462 polymorphism is very rare among Africans. This is the first report of the GSTP1 Val105 variant frequency in African populations. We show here that there are no differences in frequencies of the variant alleles for CYP1A1, GSTM1, GSTT1 and GSTP1 in the three African populations.
TL;DR: Pb-Pb isochrons have been obtained for stromatolitic limestones from the late Archaean Belingwe Greenstone Belt of Zimbabwe, providing direct age constraints on the deposition of these shallow water marine sediments as mentioned in this paper.
TL;DR: In this article, the management of water resources is best done on an integrated catchment basis; taking into account the impact of pollution on available water quantity and quality; the authors concluded that the current situation is not sustainable and recommended that the next water supply source be found outside the catchment so that its water can help flush the lake.
Abstract: The management of water resources is best done on an integrated catchment basis; taking into account the impact of pollution on available water quantity and quality. A study was done from June 2000 to March 2001 in Harare, Zimbabwe, to establish major water and nutrient flows in the Chivero subcatchment area. Lake Chivero is part of the major water supply source for Harare and is located downstream. Discharges from sewage treatment works, urban and rural agriculture, and industries, have caused a severe stress on water quality of the eutrophic lake. The study quantified major water flows through gauging stations on rivers, current metering, and hydrological modelling. Flows for raw water abstractions, sewage and water treatment works were obtained from continuous metering and pumping readings. Water samples were collected monthly for sewage, rivers and Lake Chivero, and analysed according to standard methods. Water and nutrient balances were developed. The results showed that urban water demand would exceed available treatment capacity by the year 2003. Sewage effluent presently is the major source of nutrients in the rivers. The absence of adequate flushing of the lake gives rise to accumulation of the nutrients in the lake. It was concluded that the current situation is not sustainable. It was recommended that the next water supply source be found outside the catchment so that its water can help flush the lake, and that sewage be treated to higher standards (without any pasture irrigation) and discharged directly into the rivers for recycling. The other alternative is to recycle the nutrients in controlled urban agriculture, thereby reducing fertiliser runoff. Stricter regulations and regular monitoring was recommended to control industrial pollution.
TL;DR: In 1998, South Africa and Zimbabwe promulgated new water laws to ensure that ownership and user-ship patterns of water resources match the new socio-political order as discussed by the authors, which was regarded as the cornerstone of the reforms.
Abstract: In 1998 both South Africa and Zimbabwe promulgated new water laws to ensure that ownership and user-ship patterns of water resources match the new socio-political order. Integrated water resource management, incorporating among other things decentralized and democratized water management institutions and the principles of stakeholder participation, was regarded as the cornerstone of the reforms. This article examines how stakeholder representation, particularly of the formerly disadvantaged people, has been handled. It is observed that there has been too much effort dedicated to ensure a mere headcount of the stakeholders at the water table rather than on strategic representation. Strategic representation emphasizes stakeholder identity instead of consensus. Selective alliance building is important as is establishing genuine local level platforms with enough political space outside the state-tailored formal straight jackets. It is equally important to address developmental aspects of establishing catchment-wide bodies and structural problems such as access to land and financial resources. Without addressing these issues stakeholder representation will remain hamstrung in good intentions.