Thermodynamic effects of temperature during roasting of chromite for sodium chromate salts formation

This paper aims to assess the potential effects of roasting temperature on the formation of sodium chromate (Na2CrO4). To perform this task, chromite samples were complexed with NaCl at temperatures ranging from 900 °C to 1 200 °C in the presence of excess oxygen. These experimental conditions were set and assessed based on the predicted phase transformations using Facstage as a prediction tool. The scanning electron microscopy and energy dispersive spectroscopy (SEM-EDS) have revealed the roasting behaviour of chromite to be governed by a fully reacted outside layer and an unreacted core. As per the x-ray diffraction (XRD) results, at lower temperature settings, mineral phases such as hematite and chromium oxide reported as an indication of predicted oxidation of chromite. The key results indicate that the addition of NaCl reduces the equilibrium temperature, thereby fully decomposing the stable and refractory spinel structure of chromite at 1 200 °C

Thermodynamic effects of temperature during roasting of chromite for sodium chromate salts formation

This paper aims to assess the potential effects of roasting temperature on the formation of sodium chromate (Na2CrO4). To perform this task, chromite samples were complexed with NaCl at temperatures ranging from 900 °C to 1 200 °C in the presence of excess oxygen. These experimental conditions were set and assessed based on the predicted phase transformations using Facstage as a prediction tool. The scanning electron microscopy and energy dispersive spectroscopy (SEM-EDS) have revealed the roasting behaviour of chromite to be governed by a fully reacted outside layer and an unreacted core. As per the x-ray diffraction (XRD) results, at lower temperature settings, mineral phases such as hematite and chromium oxide reported as an indication of predicted oxidation of chromite. The key results indicate that the addition of NaCl reduces the equilibrium temperature, thereby fully decomposing the stable and refractory spinel structure of chromite at 1 200 °C

The Identification of Sustainability Assessment Indicators for Road Infrastructure Projects in Tanzania

The performance of sustainability in infrastructure projects continues to face challenges in its implementation and attainment in developing countries, one of which is the lack of appraisal tools and indicators for the assessment of sustainability. Studies indicate that there are no formal indicators for sustainability assessment on road infrastructure projects in Tanzania, the lack of which limits the determination of whether projects implemented are sustainable or not. Therefore, this study aimed at determining the key sustainability assessment indicators used for road infrastructure projects in Tanzania. A concurrent mixed research approach was adopted in which the sample was purposively selected. A content analysis and descriptive statistics using the Statistical Package for the Social Sciences (SPSS 20.0) were used to analyze qualitative and quantitative data, respectively. The findings indicate that 24 indicators are applicable to Tanzania. Among the highly ranked include “health and safety training to workers”, “health and safety personnel in the project team”, “site barriers and safety warning signs”, “personal protective equipment (PPE) provision”, and “waste collection”. The qualitative results further support the identified sustainability assessment indicators on road infrastructure projects in Tanzania, with one new indicator of “air quality” emerging. The findings inform the government and other relevant stakeholders in the construction industry including planners, designers, and project managers of the key sustainability assessment indicators for roads, which would influence regulation as well as policies to improve the sustainability performance of road projects in Tanzania

Assessment of the Effect of the Oral Iron Chelator Deferiprone on Asymptomatic Plasmodium Falciparum Parasitemia in Humans

While the parenteral iron-chelating agent desferrioxamine B has anti- malarial activity in humans, the usefulness of an orally active chelator for this indication has not been investigated previously in vivo. We conducted a prospective, double-blind, placebo-controlled, cross-over trial of deferiprone (L1; CP20; 1,2-dimethyl-3-hydroxypyridin-4-one) in 25 adult Zambians with asymptomatic Plasmodium falciparum parasitemia. Deferiprone was administered daily for three or four days in divided doses of 75 or 100 mg/kg of body weight, dosages that are effective for treating iron overload. No reduction in asexual intra-erythrocytic parasites was observed during or after deferiprone treatment. The mean peak plasma concentration of deferiprone (108.9 ± 24.9 μmol/L) achieved was within the range demonstrated to inhibit the growth of P. falciparum in vitro, but the systemic exposure as determined by the 24-hr plasma concentration-time curve would not be predicted inhibit growth in vivo. No evidence of deferiprone- associated hematological toxicity was noted in this short-term study of these subjects, all of whom had clinical evidence of normal body iron stores. Because of the risk of neutropenia and other adverse effects with higher doses or prolonged use of the chelator, additional trials of deferiprone as a sole anti-malarial agent would not seem to be justified. In contrast, further efforts are needed to develop other orally active iron-chelating agents specifically for their antimalarial action

Self-efficacy enhanced in a cross-cultural context through an initiative in under-resourced schools in KwaZulu-Natal, South Africa

This paper discusses the Khanyisa Programme, an initiative in KwaZulu-Natal, South Africa, where learners from under-resourced schools are supported by teachers and high achievers in Grade 11 and 12 from a previously advantaged state school under apartheid. A qualitative, evaluative study was undertaken to identify key elements in the ongoing success of the programme and collect participant suggestions for improvement. The findings, discussed within the framework of self-efficacy theory, identified enormous gains by Khanyisa learners, leading to vastly improved career prospects

Estimation and characterization of bean seed demand in Angonia district of Mozambique

This report highlights findings of a study that was carried out to characterize and estimate the demand for common bean seed in Angonia District of Tete Province in Mozambique. The study gathered information on the area planted to the common bean annually, engaged key informants and surveyed of 332 households in eight Localidades between April and May 2015. According to the study, 99.7 % heads of households depend on agriculture as the main occupation; working on average family farm size of 1.4 ha, often augmented with 0.06 ha available through leasing annually. In addition to family-owned farms, husbands and wives solely own 30% and 26% respectively. The main crops grown in Angonia District in descending order of prevalence, were maize (97%) common bean (94%), soybean (59%) and groundnut (45%). Other crops grown included Irish potato, cowpea and tobacco. The common bean has a long history of cultivation in the district; mean bean production experience of participating farmers was 16 years

A renewable energy-centred research agenda for planning and financing Nexus development objectives in rural sub-Saharan Africa

In rural sub-Saharan Africa – the global poverty hotspot – the vast majority of cropland is rainfed only, resulting in reduced and unstable yields. Smallholder farmers account for 80% of agricultural production but they have limited access to relevant services to support both commercial operations and their livelihoods: more than two-thirds of rural dwellers have no access to electricity (crucial for crop irrigation, processing, and storage) and about 40% have no access to clean water. Previous research has analysed integrated technological and resource management approaches to tackle these overlapping development gaps. To finance and implement such transformations in resource-constrained settings, it is now crucial to understand the business and investment implications, also considering the strong regional population growth and the increasing frequency and intensity of climate extremes. Here, we lay out a research agenda that promotes the integration of multi-scale modelling excellence along the climate-water-renewable energy-agriculture-development Nexus and the creation of robust business models for private companies that can sustainably support private smallholder farmers of SSAin their effort to eradicate poverty and inequality. The proposed agenda is a cornerstone of the EC-H2020 project LEAP-RE RE4AFAGRI (“Renewable Energy for African Agriculture: Integrating Modelling Excellence and Robust Business Models”). In proposing the agenda, we highlight the importance of integrating energy access into the Nexus framework from both research and investment perspectives

Re-visiting the detection of porcine cysticercosis based on full carcass dissections of naturally Taenia solium infected pigs

Background: Taenia solium is a neglected zoonotic parasite. The performances of existing tools for the diagnosis of porcine cysticercosis need further assessment, and their shortcomings call for alternatives. The objective of this study was to evaluate the performance of tongue palpation and circulating antigen detection for the detection of porcine cysticercosis in naturally infected pigs of slaughter age compared to full carcass dissections (considered the gold standard). Additionally, alternative postmortem dissection procedures were investigated. A total of 68 rural pigs of slaughter age randomly selected in the Eastern Province of Zambia were dissected. Dissections were conducted on full carcasses (or half carcass in case cysticerci were already detected in the first half), including all the organs. Total cysticercus counts, location and stages were recorded and collected cysticerci were identified morphologically and molecularly. All sera were analysed with the B158/B60 antigen detecting ELISA (Ag-ELISA). Results: Key findings were the high occurrence of T. solium infected pigs (56%) and the presence of T. solium cysticerci in the livers of 26% of infected animals. More than half of the infected carcasses contained viable cysticerci. Seven carcasses had T. hydatigena cysticerci (10%), out of which five carcasses were co-infected with T. hydatigena and T. solium; two carcasses (3%) had only T. hydatigena cysticerci. Compared to full carcass dissection, the specificity of the Ag-ELISA to detect infected carcasses was estimated at 67%, the sensitivity at 68%, increasing to 90% and 100% for the detection of carcasses with one or more viable cysticerci, and more than 10 viable cysts, respectively. Tongue palpation only detected 10% of the cases, half carcass dissection 84%. Selective dissection of the diaphragm, tongue and heart or masseters can be considered, with an estimated sensitivity of 71%, increasing to 86% in carcasses with more than 10 cysticerci. Conclusions: Depending on the aim of the diagnosis, a combination of Ag-ELISA and selective dissection, including investigating the presence of T. hydatigena, can be considered. Full carcass dissection should include the dissection of the liver, kidneys, spleen and lungs, and results should be interpreted carefully, as small cysticerci can easily be overlooked

Overview of migration, poverty and health dynamics in Nairobi City's slum settlements

The Urbanization, Poverty, and Health Dynamics research program was designed to generate and provide the evidence base that would help governments, development partners, and other stakeholders understand how the urban slum context affects health outcomes in order to stimulate policy and action for uplifting the wellbeing of slum residents. The program was nested into the Nairobi Urban Health and Demographic Surveillance System, a uniquely rich longitudinal research platform, set up in Korogocho and Viwandani slum settlements in Nairobi city, Kenya. Findings provide rich insights on the context in which slum dwellers live and how poverty and migration status interacts with health issues over the life course. Contrary to popular opinions and beliefs that see slums as homogenous residential entities, the findings paint a picture of a highly dynamic and heterogeneous setting. While slum populations are highly mobile, about half of the population comprises relatively well doing long-term dwellers who have lived in slum settlements for over 10 years. The poor health outcomes that slum residents exhibit at all stages of the life course are rooted in three key characteristics of slum settlements: poor environmental conditions and infrastructure; limited access to services due to lack of income to pay for treatment and preventive services; and reliance on poor quality and mostly informal and unregulated health services that are not well suited to meeting the unique realities and health needs of slum dwellers. Consequently, policies and programs aimed at improving the wellbeing of slum dwellers should address comprehensively the underlying structural, economic, behavioral, and service-oriented barriers to good health and productive lives among slum residents