1996 fisheries statistics, Lake Kariba - Zimbabwe shore

The report provides catch records for the Kapenta and inshore fisheries in the Zimbabwean waters of Lake Kariba for the year 1996. Kapenta usually constitute about 90% of the total catch from Lake Kariba; for statistical purposes catches are recorded for the 5 hydrological basins - Mlibizi, Binga, Sengwa, Bumi and Kariba. Whereas kapenta represent a unit stock which is harvested by both Zimbabwe and Zambia, the artisanal fishery exploits inshore species which generally occupy water less than 10m deep along the shoreline, considered to be 2 separate stocks. The main species in the inshore fishery are Oreochromis mortimeri, Sargochromis codringtonii, Tilapia rendalli, Labeo altivelis, Hydrocynus vittatus, Mormyrus longirostris, Clarias gariepinus and Synodontis zambezensis

1995 fisheries statistics, Lake Kariba - Zimbabwe shore

The report provides catch records for the Kapenta and inshore fisheries in the Zimbabwean waters of Lake Kariba for the year 1995. Kapenta usually constitute about 90% of the total catch from Lake Kariba; for statistical purposes catches are recorded for the 5 hydrological basins - Mlibizi, Binga, Sengwa, Bumi and Kariba. Whereas kapenta represent a unit stock which is harvested by both Zimbabwe and Zambia, the artisanal fishery exploits inshore species which generally occupy water less than 10m deep along the shoreline, considered to be 2 separate stocks. The main species in the inshore fishery are Oreochromis mortimeri, Sargochromis codringtonii, Tilapia rendalli, Labeo altivelis, Hydrocynus vittatus, Mormyrus longirostris, Clarias gariepinus and Synodontis zambezensis

Evaluation Of The Impact Of Scanning Strategies On Residual Stresses In Selective Laser Melting

Published ArticleThe occurrence of residual stresses in selective laser melting (SLM) presents challenges that limit the capability of the process to manufacture parts at industrial scale. These stresses can have irreversible effects such as warping and cracking of parts during and post manufacturing.One of the most important SLMparameters that should be controlled carefully in order to effectively manage residual stresses is the scanning strategy. This study presents an evaluation of four different scanning strategies, namely the island, successive, successive chessboard and least heat influence (LHI) scanning strategies with respect to their influence on residual stresses and distortions. All the scanning strategies were investigated by melting single tracks on tool steel substrates without powder. Measurement of residual stresses was performed on selected positions on the substrates before and after exposure to the laser beam using the x-ray diffraction technique. The successive chessboard scanning strategy was found to contribute to the least average residual stresses, and lowered residual stress by up to 40% relative to the default island scanning strategy. Further to this, the influence of the successive chessboard and island scanning strategies on distortions was evaluated. Similar to the residual stress findings, the successive chessboard contributed to lower form deviations compared to the island strategy. The scanning strategies were also evaluated based on their impact on total scanning times, with the successive chessboard strategy showing slightly lower scanning time than that for the island and LHI chessboard strategies

Nitrogen effect on zinc biofortification of maize and cowpea in Zimbabwean smallholder farms

Agronomic biofortification of crops with zinc (Zn) can be enhanced under increased nitrogen (N) supply. Here, the effects of N fertilizer on grain Zn concentration of maize (Zea mays L.) and cowpea (Vigna unguiculata L.) were determined at two contrasting sites in Zimbabwe over two seasons. All treatments received soil and foliar zinc‐sulphate fertilizer. Seven N treatments, with three N rates (0, 45, and 90 kg ha−1 for maize; 0, 15, and 30 kg ha−1 for cowpea), two N forms (mineral and organic), and combinations thereof were used for each crop in a randomized complete block design (n = 4). Maize grain Zn concentrations increased from 27.2 to 39.3 mg kg−1 across sites. At 45 kg N ha−1, mineral N fertilizer increased maize grain Zn concentration more than organic N from cattle manure or a combination of mineral and organic N fertilizers. At 90 kg N ha−1, the three N fertilizer application strategies had similar effects on maize grain Zn concentration. Co‐application of N and Zn fertilizer was more effective at increasing Zn concentration in maize grain than Zn fertilizer alone. Increases in cowpea grain Zn concentration were less consistent, although grain Zn concentration increased from 39.8 to 52.7 mg kg−1 under optimal co‐applications of N and Zn. Future cost/benefit analyses of agronomic biofortification need to include information on benefits of agro‐fortified grain, complex farmer management decisions (including cost and access to both N and Zn fertilizers), as well as understanding of the spatial and site‐specific variation in fertilizer responses

WHO 2010 Guidelines for Prevention of Mother-to-Child HIV Transmission in Zimbabwe: Modeling Clinical Outcomes in Infants and Mothers

The Zimbabwean national prevention of mother-to-child HIV transmission (PMTCT) program provided primarily single-dose nevirapine (sdNVP) from 2002-2009 and is currently replacing sdNVP with more effective antiretroviral (ARV) regimens.Published HIV and PMTCT models, with local trial and programmatic data, were used to simulate a cohort of HIV-infected, pregnant/breastfeeding women in Zimbabwe (mean age 24.0 years, mean CD4 451 cells/µL). We compared five PMTCT regimens at a fixed level of PMTCT medication uptake: 1) no antenatal ARVs (comparator); 2) sdNVP; 3) WHO 2010 guidelines using "Option A" (zidovudine during pregnancy/infant NVP during breastfeeding for women without advanced HIV disease; lifelong 3-drug antiretroviral therapy (ART) for women with advanced disease); 4) WHO "Option B" (ART during pregnancy/breastfeeding without advanced disease; lifelong ART with advanced disease); and 5) "Option B+:" lifelong ART for all pregnant/breastfeeding, HIV-infected women. Pediatric (4-6 week and 18-month infection risk, 2-year survival) and maternal (2- and 5-year survival, life expectancy from delivery) outcomes were projected.Eighteen-month pediatric infection risks ranged from 25.8% (no antenatal ARVs) to 10.9% (Options B/B+). Although maternal short-term outcomes (2- and 5-year survival) varied only slightly by regimen, maternal life expectancy was reduced after receipt of sdNVP (13.8 years) or Option B (13.9 years) compared to no antenatal ARVs (14.0 years), Option A (14.0 years), or Option B+ (14.5 years).Replacement of sdNVP with currently recommended regimens for PMTCT (WHO Options A, B, or B+) is necessary to reduce infant HIV infection risk in Zimbabwe. The planned transition to Option A may also improve both pediatric and maternal outcomes

Early infant HIV-1 diagnosis programs in resource-limited settings: opportunities for improved outcomes and more cost-effective interventions

Early infant diagnosis (EID) of HIV-1 infection confers substantial benefits to HIV-infected and HIV-uninfected infants, to their families, and to programs providing prevention of mother-to-child transmission (PMTCT) services, but has been challenging to implement in resource-limited settings. In order to correctly inform parents/caregivers of infant infection status and link HIV-infected infants to care and treatment, a 'cascade' of events must successfully occur. A frequently cited barrier to expansion of EID programs is the cost of the required laboratory assays. However, substantial implementation barriers, as well as personnel and infrastructure requirements, exist at each step in the cascade. In this update, we review challenges to uptake at each step in the EID cascade, highlighting that even with the highest reported levels of uptake, nearly half of HIV-infected infants may not complete the cascade successfully. We next synthesize the available literature about the costs and cost effectiveness of EID programs; identify areas for future research; and place these findings within the context of the benefits and challenges to EID implementation in resource-limited settings

Influence of process parameters on residual stress related distortions in selective laser melting

CITATION: Mugwagwa, L., et al. 2018. Influence of process parameters on residual stress related distortions in selective laser melting. Procedia Manufacturing, 21:92-99, doi:10.1016/j.promfg.2018.02.099.The original publication is available at https://www.sciencedirect.comENGLISH ABSTRACT: Residual stresses pose a major setback in Selective Laser Melting (SLM) and limit the applicability of the process, particularly from the standpoint of form accuracy and mechanical strength. The purpose of this paper is to investigate the influence of SLM parameters namely laser power and scanning speed on thermal stress related warping distortions and porosity. In this study, residual stress related distortions and achievable density for different process parameter combinations are presented simultaneously due to the profound influence of the porosity on residual stress relaxation. The paper also discusses the implications of the process parameters on the sustainability of the SLM process.https://www.sciencedirect.com/science/article/pii/S2351978918301343Publisher's versio

Nivolumab-induced myocarditis complicated by complete atrioventricular block in a patient with metastatic non-small cell lung cancer

We report a case of a 74-year-old man who developed myocarditis complicated by atrioventricular (AV) block following two doses of nivolumab for the treatment of non-small cell lung cancer. A diagnosis of drug-induced acute myocarditis with complete AV block was considered on the basis of elevated troponin, new onset left ventricular (LV) systolic dysfunction, absence of acute myocardial infarction and some findings suggestive of myocarditis on cardiac magnetic resonance. The patient was commenced on glucocorticoids, perindopril and carvedilol. AV block and LV dysfunction persisted despite 2 weeks of treatment. He ultimately became hypotensive which prompted an implantation of a cardiac resynchronisation therapy pacemaker. Follow-up echocardiogram at 6 weeks showed resolution of LV systolic dysfunction. However, he continued to have AV block.Jin Lin Tan, Augustine Nyasha Mugwagwa, Luke Cieslik, Rohit Josh

A methodology to evaluate the influence of part geometry on residual stresses in selective laser melting

CITATION: Mugwagwa, L., et al. 2016. A methodology to evaluate the influence of part geometry on residual stresses in selective laser melting. In Competitive Manufacturing, International Conference on Competitive Manufacturing (COMA '16), 27-29 January 2016, Stellenbosch, Stellenbosch University, South Africa.The original publication is available at http://conferences.sun.ac.za/index.php/doie/coma16ENGLISH ABSTRACT: The subject of residual stresses induced by the Selective Laser Melting (SLM) process has been one of the main focus areas in literature over the past decade. It has been reported that residual stresses can be responsible for shape and dimensional distortions, cracking and compromised mechanical properties (reduced yield and fatigue strength). These shortfalls limit the applicability of SLM components in industry, particularly for the aerospace industry where part lifetime and hence fatigue life is of utmost concern. High temperature gradients have been reported to be responsible for the residual stress build up. A key aspect that has not been considered in literature is part geometry and orientation and its influence on residual stress levels. Thus, this study proposes a methodology for investigating this influence for different geometric features. In this work, samples were built from tool steel powders. The Hole Drilling Method (HDM) and X-Ray Diffraction (XRD) techniques are proposed for measuring residual stresses. Preliminary results show that the geometry of a part influences residual stress magnitudes and distributions, with sharper ends exhibiting higher stresses than less sharp specimen ends.AFRIKAANSE OPSOMMING: Geen opsomming beskikbaarPublishers versio