Showing papers by "University of Zimbabwe published in 2018"

Synthesis and nutrient release patterns of a biochar-based N–P–K slow-release fertilizer

Abstract: Biochar has excellent solute adsorption capacity, yet few studies have investigated its application as a nutrient carrier in the development of slow-release fertilizers. The current study developed a biochar-based N–P–K fertilizer (BSRF) and evaluated its nutrient release patterns relative to a conventional fertilizer. SEM and EDX analyses confirmed the coarse and highly porous microstructure of the biochar (SBC) that enabled it to effectively sorb NO3 −, PO4 3−, and K+ and form a nutrient-impregnated BSRF. BSRF had lower NO3 −, PO4 3−, and K+ release than the conventional chemical fertilizer, demonstrating its low release behavior. BSRF-amended sandy soil had higher water retention capacity than that amended with a conventional chemical fertilizer. BSRF has potential to reduce nutrient leaching, improve water retention, and hence increase crop nutrient and water use efficiencies. Future research should focus on understanding nutrient release mechanisms, synchronization of nutrient release with plant uptake, and applications of the BSRF in environmental remediation.

Evaluation of Intussusception after Monovalent Rotavirus Vaccination in Africa

Abstract: Background Postlicensure evaluations have identified an association between rotavirus vaccination and intussusception in several high- and middle-income countries. We assessed the association between monovalent human rotavirus vaccine and intussusception in lower-income sub-Saharan African countries. Methods Using active surveillance, we enrolled patients from seven countries (Ethiopia, Ghana, Kenya, Malawi, Tanzania, Zambia, and Zimbabwe) who had intussusception that met international (Brighton Collaboration level 1) criteria. Rotavirus vaccination status was confirmed by review of the vaccine card or clinic records. The risk of intussusception within 1 to 7 days and 8 to 21 days after vaccination among infants 28 to 245 days of age was assessed by means of the self-controlled case-series method. Results Data on 717 infants who had intussusception and confirmed vaccination status were analyzed. One case occurred in the 1 to 7 days after dose 1, and 6 cases occurred in the 8 to 21 days after dose...

Revisiting IPCC Tier 1 coefficients for soil organic and biomass carbon storage in agroforestry systems

Abstract: Agroforestry systems comprise trees and crops, or trees and pastures within the same field. Globally, they cover approximately 1 billion hectares of land and contribute to the livelihoods of over 900 million people. Agroforestry systems have the capacity to sequester large quantities of carbon (C) in both soil and biomass. However, these systems have not yet been fully considered in the approach to C accounting developed by the Intergovernmental Panel on Climate Change, largely due to the high diversity of agroforestry systems and scarcity of relevant data. Our literature review identified a total of 72 scientific, peer-reviewed articles associated with biomass C storage (50) and with soil organic carbon (SOC) (122), containing a total of 542 observations (324 and 218, respectively). Based on a synthesis of the reported observations, we are presenting a set of Tier 1 coefficients for biomass C storage for each of the eight main agroforestry systems identified, including alley cropping, fallows, hedgerows, multistrata, parklands, shaded perennial-crop, silvoarable and silvopastoral systems, disaggregated by climate and region. Using the same agroforestry classification, we are presenting a set of stock change factors (F LU ) and SOC accumulation/loss rates for three main land use changes (LUCs): cropland to agroforestry; forest to agroforestry; and grassland to agroforestry. Globally, the mean SOC stock change factors (± confidence intervals) were estimated to be 1.25 ± 0.04, 0.89 ± 0.07, and 1.19 ± 0.10, for the three main LUCs, respectively. However, these average coefficients hide huge disparities across and within different climates, regions, and types of agroforestry systems, highlighting the necessity to adopt the more disaggregated coefficients provided herein. We encourage national governments to synthesize data from local field experiments to generate country-specific factors for more robust estimation of biomass and SOC storage.

Escherichia coli Contamination across Multiple Environmental Compartments (Soil, Hands, Drinking Water, and Handwashing Water) in Urban Harare: Correlations and Risk Factors.

Abstract: Escherichia coli pathotypes (i.e., enteropathogenic and enterotoxigenic) have been identified among the pathogens most responsible for moderate-to-severe diarrhea in low- and middle-income countries (LMICs). Pathogenic E. coli are transmitted from infected human or animal feces to new susceptible hosts via environmental reservoirs such as hands, water, and soil. Commensal E. coli, which includes nonpathogenic E. coli strains, are widely used as fecal bacteria indicator, with their presence associated with increased likelihood of enteric pathogens and/or diarrheal disease. In this study, we investigated E. coli contamination in environmental reservoirs within households (N = 142) in high-population density communities of Harare, Zimbabwe. We further assessed the interconnectedness of the environmental compartments by investigating associations between, and household-level risk factors for, E. coli contamination. From the data we collected, the source and risk factors for E. coli contamination are not readily apparent. One notable exception is the presence of running tap water on the household plot, which is associated with significantly less E. coli contamination of drinking water, handwashing water, and hands after handwashing. In addition, E. coli levels on hands after washing are significantly associated with handwashing water contamination, hand contamination before washing, and diarrhea incidence. Finally, we observed that animal ownership increases E. coli contamination in soil, and E. coli in soil are correlated with contamination on hands before washing. This study highlights the complexity of E. coli contamination in household environments within LMICs. More, larger, studies are needed to better identify sources and exposure pathways of E. coli-and enteric pathogens generally-to identify effective interventions.

Gendered health systems: evidence from low- and middle-income countries.

Abstract: Gender is often neglected in health systems, yet health systems are not gender neutral. Within health systems research, gender analysis seeks to understand how gender power relations create inequities in access to resources, the distribution of labour and roles, social norms and values, and decision-making. This paper synthesises findings from nine studies focusing on four health systems domains, namely human resources, service delivery, governance and financing. It provides examples of how a gendered and/or intersectional gender approach can be applied by researchers in a range of low- and middle-income settings (Cambodia, Zimbabwe, Uganda, India, China, Nigeria and Tanzania) to issues across the health system and demonstrates that these types of analysis can uncover new and novel ways of viewing seemingly intractable problems. The research used a combination of mixed, quantitative, qualitative and participatory methods, demonstrating the applicability of diverse research methods for gender and intersectional analysis. Within each study, the researchers adapted and applied a variety of gender and intersectional tools to assist with data collection and analysis, including different gender frameworks. Some researchers used participatory tools, such as photovoice and life histories, to prompt deeper and more personal reflections on gender norms from respondents, whereas others used conventional qualitative methods (in-depth interviews, focus group discussion). Findings from across the studies were reviewed and key themes were extracted and summarised. Five core themes that cut across the different projects were identified and are reported in this paper as follows: the intersection of gender with other social stratifiers; the importance of male involvement; the influence of gendered social norms on health system structures and processes; reliance on (often female) unpaid carers within the health system; and the role of gender within policy and practice. These themes indicate the relevance of and need for gender analysis within health systems research. The implications of the diverse examples of gender and health systems research highlighted indicate that policy-makers, health practitioners and others interested in enhancing health system research and delivery have solid grounds to advance their enquiry and that one-size-fits-all heath interventions that ignore gender and intersectionality dimensions require caution. It is essential that we build upon these insights in our efforts and commitment to move towards greater equity both locally and globally.

Feasibility and Acceptability of a Task-Shifted Intervention to Enhance Adherence to HIV Medication and Improve Depression in People Living with HIV in Zimbabwe, a Low Income Country in Sub-Saharan Africa

Abstract: Using a pilot trial design in an HIV care clinic in Zimbabwe, we randomised 32 adults with poor adherence to antiretroviral therapy and at least mild depression to either six sessions of Problem-Solving Therapy for adherence and depression (PST-AD) delivered by an adherence counsellor, or to Enhanced Usual Care (Control). Acceptability of PST-AD was high, as indicated by frequency of session attendance and through qualitative analyses of exit interviews. Fidelity was >80% for the first two sessions of PST-AD but fidelity to the adherence component of PST-AD dropped by session 4. Contamination occurred, in that seven patients in the control arm received one or two PST-AD sessions before follow-up assessment. Routine health records proved unreliable for measuring HIV viral load at follow-up. Barriers to measuring adherence electronically included device failure and participant perception of being helped by the research device. The study was not powered to detect clinical differences, however, promising change at 6-months follow-up was seen in electronic adherence, viral load suppression (PST-AD arm 9/12 suppressed; control arm 4/8 suppressed) and depression (Patient Health Questionnaire-4.7 points in PST-AD arm vs. control, adjusted p value = 0.01). Results inform and justify a future randomised controlled trial of task-shifted PST-AD.

Utilization of bambara groundnut (Vigna subterranea (L.) Verdc.) for sustainable food and nutrition security in semi-arid regions of Zimbabwe.

Abstract: Bambara groundnut (Vigna subterranea (L.) Verdc.) is an indigenous legume crop, cultivated by subsistence farmers throughout sub-Saharan countries. Research findings indicate that the crop has great nutritional and agronomic potential, but it remains scientifically neglected. A baseline study was conducted in seven districts in semi-arid regions of rural Zimbabwe to gather knowledge on current production and utilization of bambara groundnut, assess its role in providing sustainable food and nutrition security for rural populations and determine priorities for follow-up research. Results revealed a variety of bambara groundnut processing techniques, which included boiling, soaking, roasting and milling across the surveyed districts. Reported constraints to processing and consumption included long cooking time, difficulties with milling and high firewood and water requirements. Fifty to eighty percent of respondents in all districts consumed bambara groundnut once or twice weekly from August to December. Preferred consumer attributes were taste, the satiating effect, nutritional benefits or a combination of these. Current, culturally acceptable processing techniques need improvement to support sustainable bambara groundnut processing while optimising nutrient bio-accessibility. Ultimately, community resilience to food and nutrition insecurity can be promoted by exchange of bambara groundnut processing knowledge amongst the production areas, involving the different stakeholders in the food supply chains.

Circadian oscillations of cytosolic free calcium regulate the Arabidopsis circadian clock

Abstract: In the last decade, the view of circadian oscillators has expanded from transcriptional feedback to incorporate post-transcriptional, post-translational, metabolic processes and ionic signalling. In plants and animals, there are circadian oscillations in the concentration of cytosolic free Ca2+ ([Ca2+]cyt), though their purpose has not been fully characterized. We investigated whether circadian oscillations of [Ca2+]cyt regulate the circadian oscillator of Arabidopsis thaliana. We report that in Arabidopsis, [Ca2+]cyt circadian oscillations can regulate circadian clock function through the Ca2+-dependent action of CALMODULIN-LIKE24 (CML24). Genetic analyses demonstrate a linkage between CML24 and the circadian oscillator, through pathways involving the circadian oscillator gene TIMING OF CAB2 EXPRESSION1 (TOC1).

Sources, behaviour and health risks of antimicrobial resistance genes in wastewaters: A hotspot reservoir

Abstract: Limited reviews have investigated sources, behaviour and health risks of antimicrobial resistance genes (ARGs) in the wastewater-human pathway. The current review seeks to: (1) determine hotspot sources of ARGs, and their behaviour and fate in wastewaters; (2) discuss ARG health risks, and risk factors; and (3) highlight future research directions. Diverse ARGs conferring single and multi-drug resistance to common and last-resort antimicrobials are widely reported. Hotspot sources of ARGs include medical facilities, pharmaceutical industries, aquaculture and animal systems. Non-engineered landfills, on-site sanitation, funeral parlours and gravesites constitute under-studied potential hotspot sources. Hydrological processes, wind and vectors mobilize ARGs from sources into aquatic systems. Wastewater treatment processes, the nature of ARGs and environmental conditions control the behaviour and fate of ARGs. Consumption of contaminated food and water, vectors, inhalation and dermal contact transfer ARGs from wastewaters to humans. Health risks include development of antimicrobial resistance, although evidence directly linking ARGs in wastewater to resistance remains weak. Ecological risks include shifts in physiological behaviour, community structure and ecosystem functions, including expression of shock-responses and virulence, biofilm formation and mutations. These shifts could increase colonization ability and survival of pathogenic microbes, thereby posing significant ecological, human and animal health risks. Overall, the behaviour and risks of ARGs are controlled by complex human-environmental interactions, and have far-reaching policy implications, hence ARGs can be considered as a ‘super-wicked’ problem. To minimize the risks, a conceptual framework entailing a ten-point strategy is highlighted. Under-studied hotspot sources, behaviour and fate, human ecotoxicology and risk assessments warrant further research.

Geospatial distribution of Mycobacterium tuberculosis genotypes in Africa

Abstract: CITATION: Chihota, V. N., et al. 2018. Geospatial distribution of Mycobacterium tuberculosis genotypes in Africa. PLoS ONE, 13(8):e0200632, doi:10.1371/journal.pone.0200632.

Malaria knowledge and bed net use in three transmission settings in southern Africa

Abstract: Insecticide-treated nets (ITNs) reduce malaria morbidity and mortality in endemic areas. Despite increasing availability, the use of ITNs remains limited in some settings. Poor malaria knowledge is a barrier to the widespread use of ITNs. The goal of this study was to assess the levels of malaria knowledge and evaluate factors associated with bed net use among individuals residing in three regions of southern Africa with different levels of malaria transmission and control. A cross-sectional study was conducted on a sample of 7535 residents recruited from 2066 households in Mutasa District, Zimbabwe (seasonal malaria transmission), Choma District, Zambia (low transmission) and Nchelenge District, Zambia (high transmission), between March 2012 and March 2017. A standardized questionnaire was used to collect data on demographics, malaria-related knowledge and use of preventive measures. Multivariate logistic regression analyses were used to assess determinants of bed net use. Most of the 3836 adult participants correctly linked mosquito bites to malaria (85.0%), mentioned at least one malaria symptom (95.5%) and knew of the benefit of sleeping under an ITN. Bed net ownership and use were highest in Choma and Nchelenge Districts and lowest in Mutasa District. In multivariate analyses, knowledge of ITNs was associated with a 30–40% increased likelihood of bed net use after adjusting for potential confounders across all sites. Other factors significantly associated with bed net use were age, household size and socioeconomic status, although the direction, strength and size of association varied by study site. Importantly, participants aged 5–14 years had reduced odds of sleeping under a bed net compared to children younger than 5 years. Relevant knowledge of ITNs translated into the expected preventive behaviour of sleeping under a bed net, underscoring the need for continued health messaging on malaria prevention. The implementation and delivery of malaria control and elimination interventions needs to consider socioeconomic equity gaps, and target school-age children to ensure access to and improve utilization of ITNs.

The growing burden of noncommunicable disease among persons living with HIV in Zimbabwe.

Abstract: Objectives:We aim to characterize the future noncommunicable disease (NCD) burden in Zimbabwe to identify future health system priorities.Methods:We developed an individual-based multidisease model for Zimbabwe, simulating births, deaths, infection with HIV and progression and key NCD [asthma, chron

The adoption of sustainable agricultural practices by smallholder farmers in Ethiopian highlands: An integrative approach

Abstract: The adoption of Sustainable Agricultural Practices (SAPs) remains high on the policy and research agenda in most of sub-Saharan Africa. This paper adopts an integrative approach to investigate how ...

Development, engineering properties and potential applications of unfired earth bricks reinforced by coal fly ash, lime and wood aggregates

Abstract: The current study developed and evaluated the engineering properties of improved low-cost UEBs reinforced with various lime (L)-coal fly ash (F)-wood aggregate (W) mix ratios. The objectives were; (1) to determine the effects of lime-coal fly ash-wood aggregate mixtures on mechanical strength and water resistance properties of UEBs; and (2) to determine the comparative cost of the improved UEBs to that of the control (10% cement). Four UEBs with various lime (L)-coal fly ash (F)-wood aggregates (W) mix ratios (L4%-F16%-W1.5%; L4%-F16%-W3%; L8%-F12%-W3%; L10%-F10%-W1.5%) were fabricated and their engineering properties compared to those of unstabilised (negative control) and 10% cement stabilized (positive control) unfired earth bricks. Dry compressive strength (DCS) of UEBs stabilized by L10%-F10%-W1.5% (8.3 MPa) was significantly higher (p masonry units . DCS increased with lime-fly ash ratio according to a power function ( y = − 5.41 x 2 + 11.18 x + 2.22 ; r2 =0.95, p = 0.018), attaining a maximum of 8.3 MPa at a ratio of 1: 1. However, UEBs had low wet strength, but incorporation of 4% cement significantly increased (p

Virological failure among adolescents on ART, Harare City, 2017- a case-control study

Abstract: Zimbabwe is on track towards achieving viral suppression among adults (87%). However, adolescents have only achieved 44% by 2016. In Harare city, 57% of adolescents had attained viral suppression after 12 months on ART compared to 88% among adults. We determined factors associated with virological failure among adolescents (age 10–19 years) on antiretroviral therapy (ART) in Harare city. We conducted a one to one unmatched case control study among 102 randomly recruited case: control pairs at the two main infectious disease hospitals in Harare. A case was any adolescent who presented with VL > 1000c/ml after at least 12 months on ART. A control was any adolescent who presented with VL < 1000c/ml after at least 12 months on ART. Interviewer administered questionnaires were used to collect data. Epi Info 7 was used to generate frequencies, means, proportions, ORs and p-values at 95% CI. We interviewed 102 case-control pairs. Poor adherence to ART [aOR = 8.15, 95% CI (2.80–11.70)], taking alcohol [aOR = 8.46, 95% CI (3.22–22.22)] and non- disclosure of HIV status [aOR = 4.56, 95% CI (2.20–9.46)] were independent risk factors for virological failure. Always using a condom [aOR = 0.04, 95% CI (0.01–0.35)], being on second line treatment [aOR = 0.04, 95% CI (0.23–0.81)] and belonging to a support group [aOR = 0.41, 95% CI (0.21–0.80)] were protective. Poor adherence, alcohol consumption and non-disclosure increased the odds of virological failure. Based on these findings support should focus on behavior change and strengthening of peer to peer projects to help address issues related to disclosure and adherence. Further operational research should aim to define other components of effective adherence support for adolescents with virological failure.

The role of community health workers in improving HIV treatment outcomes in children: lessons learned from the ZENITH trial in Zimbabwe.

Abstract: Reliance on community health workers (CHWs) for HIV care continues to increase, particularly in resource-limited settings. CHWs can improve HIV service use and adherence to treatment, but effectiveness of these programmes relies on providing an enabling work environment for CHWs, including reasonable workload, supportive supervision and adequate training and supplies. Although criteria for effective CHW programmes have been identified, these have rarely been prospectively applied to design and evaluation of new interventions. For the Zimbabwe study for Enhancing Testing and Improving Treatment of HIV in Children (ZENITH) randomized controlled trial, we based our intervention on an existing evidence-based framework for successful CHW programmes. To assess CHWs' experiences delivering the intervention, we conducted longitudinal, qualitative semi-structured interviews with all 19 CHWs at three times during implementation. The study aimed to explore CHWs' perceptions of how the intervention's structure and management affected their performance, and consider implications for the programme's future scale-up and adoption in other settings. CHWs expressed strong motivation, commitment and job satisfaction. They considered the intervention acceptable and feasible to deliver, and levels of satisfaction rose over interview rounds. Intensive supervision and mentoring emerged as critical to ensuring CHWs' long-term satisfaction. Provision of job aids, standardized manuals and refresher training were also important, as were formalized links between clinics and CHWs. Concerns raised by CHWs included poor remuneration, their reluctance to stop providing support to individual families following the requisite number of home visits, and disappointment at the lack of programme sustainability following completion of the trial. Furthermore, intensive supervision and integration with clinical services may be difficult to replicate outside a trial setting. This study shows that existing criteria for designing successful CHW programmes are useful for maximizing effectiveness, but challenges remain for ensuring long-term sustainability of 'task shifting' strategies.

Sedimentation and Its Impacts/Effects on River System and Reservoir Water Quality: case Study of Mazowe Catchment, Zimbabwe

Abstract: . Sediment delivery into water sources and bodies results in the reduction of water quantity and quality, increasing costs of water purification whilst reducing the available water for various other uses. The paper gives an analysis of sedimentation in one of Zimbabwe's seven rivers, the Mazowe Catchment, and its impact on water quality. The Revised Universal Soil Loss Equation (RUSLE) model was used to compute soil lost from the catchment as a result of soil erosion. The model was used in conjunction with GIS remotely sensed data and limited ground observations. The estimated annual soil loss in the catchment indicates soil loss ranging from 0 to 65 t ha yr−1. Bathymetric survey at Chimhanda Dam showed that the capacity of the dam had reduced by 39 % as a result of sedimentation and the annual sediment deposition into Chimhanda Dam was estimated to be 330 t with a specific yield of 226 t km−2 yr−1. Relationship between selected water quality parameters, TSS, DO, NO3, pH, TDS, turbidity and sediment yield for selected water sampling points and Chimhanda Dam was analyzed. It was established that there is a strong positive relationship between the sediment yield and the water quality parameters. Sediment yield showed high positive correlation with turbidity (0.63) and TDS (0.64). Water quality data from Chimhanda treatment plant water works revealed that the quality of water is deteriorating as a result of increase in sediment accumulation in the dam. The study concluded that sedimentation can affect the water quality of water sources.

Human Immunodeficiency Virus-Associated Chronic Lung Disease in Children and Adolescents in Zimbabwe: Chest Radiographic and High-Resolution Computed Tomographic Findings.

Abstract: Background Chronic respiratory symptoms are common among children living with human immunodeficiency virus (HIV). We investigated the radiological features of chronic lung disease in children aged 6–16 years receiving antiretroviral therapy for ≥6 months in Harare, Zimbabwe. Methods Consecutive participants from a HIV clinic underwent clinical assessment and chest radiography. Participants with an abnormal chest radiograph (assessed by a clinician) and/or those meeting a clinical case definition for chronic lung disease underwent high-resolution computed tomography (HRCT). Radiological studies were scored independently and blindly by 2 thoracic radiologists. Relationships between radiological abnormalities and lung function were examined. Results Among 193 participants (46% female; median age, 11.2 years; interquartile range, 9.0–12.8 years), the median CD4 cell count was 720/µL (473–947/µL), and 79% had a human immunodeficiency virus (HIV) load of <400 copies/mL. The most common chest radiographic finding was ring/tramline opacities (55 of 193 participants; 29%). HRCT scans were evaluated in 84 participants (69%); decreased attenuation (present in 43%) was the dominant abnormality seen. The extent of decreased attenuation was strongly correlated with both the severity and extent of bronchiectasis (rs = 0.68 and P < .001 for both). The extent of decreased attenuation was also negatively correlated with forced expiratory volume in first second of expiration (rs = –0.52), forced vital capacity (rs = –0.42), and forced expiratory flow, midexpiratory phase (rs = –0.42) (P < .001 for all). Conclusions The HRCT findings strongly suggest that obliterative bronchiolitis may be the major cause of chronic lung disease in our cohort. Further studies to understand the pathogenesis and natural history are urgently needed.

Inventory on the dietary assessment tools available and needed in Africa: a prerequisite for setting up a common methodological research infrastructure for nutritional surveillance, research and prevention of diet-related non-communicable diseases

Abstract: Objective: To carry out an inventory on the availability, challenges and needs of Dietary Assessment (DA) methods in Africa as a pre-requisite to provide evidence, and set directions (strategies) for implementing common dietary methods and support web-research infrastructure across countries.Methods: The inventory was performed within the framework of the “Africa's Study on Physical Activity and Dietary Assessment Methods” (AS-PADAM) project. It involves International Institutional and African networks. An inventory questionnaire was developed and disseminated through the networks. Eighteen countries responded to the dietary inventory questionnaire.Results: Various DA tools were reported in Africa, 24-Hour Dietary Recall and Food Frequency Questionnaire were the most commonly used. Few tools were validated and tested for reliability. Face-to-face interview was the common method of administration. No computerised software or other new (web) technologies were reported. No tools were standardised acr...

Lopinavir plus nucleoside reverse-transcriptase inhibitors, lopinavir plus raltegravir, or lopinavir monotherapy for second-line treatment of HIV (EARNEST): 144-week follow-up results from a randomised controlled trial.

Abstract: Summary Background Millions of HIV-infected people worldwide receive antiretroviral therapy (ART) in programmes using WHO-recommended standardised regimens. Recent WHO guidelines recommend a boosted protease inhibitor plus raltegravir as an alternative second-line combination. We assessed whether this treatment option offers any advantage over the standard protease inhibitor plus two nucleoside reverse-transcriptase inhibitors (NRTIs) second-line combination after 144 weeks of follow-up in typical programme settings. Methods We analysed the 144-week outcomes at the completion of the EARNEST trial, a randomised controlled trial done in HIV-infected adults or adolescents in 14 sites in five sub-Saharan African countries (Uganda, Zimbabwe, Malawi, Kenya, Zambia). Participants were those who were no longer responding to non-NRTI-based first-line ART, as assessed with WHO criteria, confirmed by viral-load testing. Participants were randomly assigned to receive a ritonavir-boosted protease inhibitor (lopinavir 400 mg with ritonavir 100 mg, twice per day) plus two or three clinician-selected NRTIs (protease inhibitor plus NRTI group), protease inhibitor plus raltegravir (400 mg twice per day; protease inhibitor plus raltegravir group), or protease inhibitor monotherapy (plus raltegravir induction for first 12 weeks, re-intensified to combination therapy after week 96; protease inhibitor monotherapy group). Randomisation was by computer-generated randomisation sequence, with variable block size. The primary outcome was viral load of less than 400 copies per mL at week 144, for which we assessed non-inferiority with a one-sided α of 0·025, and superiority with a two-sided α of 0·025. The EARNEST trial is registered with ISRCTN, number 37737787. Findings Between April 12, 2010, and April 29, 2011, 1837 patients were screened for eligibility, of whom 1277 patients were randomly assigned to an intervention group. In the primary (complete-case) analysis at 144 weeks, 317 (86%) of 367 in the protease inhibitor plus NRTI group had viral loads of less than 400 copies per mL compared with 312 (81%) of 383 in the protease inhibitor plus raltegravir group (p=0·07; lower 95% confidence limit for difference 10·2% vs specified non-inferiority margin 10%). In the protease inhibitor monotherapy group, 292 (78%) of 375 had viral loads of less than 400 copies per mL; p=0·003 versus the protease inhibitor plus NRTI group at 144 weeks. There was no difference between groups in serious adverse events, grade 3 or 4 adverse events (total or ART-related), or events that resulted in treatment modification. Interpretation Protease inhibitor plus raltegravir offered no advantage over protease inhibitor plus NRTI in virological efficacy or safety. In the primary analysis, protease inhibitor plus raltegravir did not meet non-inferiority criteria. A regimen of protease inhibitor with NRTIs remains the best standardised second-line regimen for use in programmes in resource-limited settings. Funding European and Developing Countries Clinical Trials Partnership (EDCTP), UK Medical Research Council, Instituto de Salud Carlos III, Irish Aid, Swedish International Development Cooperation Agency, Instituto Superiore di Sanita, Merck, ViiV Healthcare, WHO.

Bambara groundnut (Vigna subterranea (L.) Verdc.) flour: A functional ingredient to favour the use of an unexploited sustainable protein source

Abstract: Variability in dehulling efficiency, colour, chemical composition and selected functional properties of raw and pre-treated bambara groundnut (Vigna subterranea (L.) Verdc.) (BG) flour from red and black-eye varieties were studied. Functional properties were water and oil absorption, gelation, pasting, emulsification and foaming capacity. Pre-treatment of seeds (i.e. soaking, roasting and combined soaking and roasting) improved dehulling efficiency of BG varieties. Protein content of flour ranged from 15.6-19.6%, starch from 47.8-52.0% and sucrose from 1.9-5%. An improvement was observed for protein and ash content of pre-treated flour compared to raw flour. Heat treatments increased onset gelatinization temperature of flour. Black-eye BG flours that had higher starch content, also had better gelation capacity than red BG flours. All pre-treatment methods decreased flour emulsification capacity and stability. Dry-roasting caused a greater decline than other methods, whereas soaking had little effect on emulsion stability. Further, soaking increased foaming capacity, whilst a decline was observed in roasted flour. All pre-treatment methods increased oil absorption capacity of both BG flour varieties. Overall, soaked and combined soaked and roasted flour is recommended for BG flour to be incorporated in food products.

Surface water bodies mapping in Zimbabwe using landsat 8 OLI multispectral imagery: A comparison of multiple water indices

Abstract: Water is integral for the survival of humans, animals, as well as vegetation and information on its spatial distribution is important for water resources management. Various methods have been applied to detect and map land surface water, especially due to the availability of a large range of satellite sensors. The main methods involved are either general feature classification techniques or thematic water body information extraction. Thematic water body extraction methods make use of band information and in this study; spectral indices are used to delineate land surface water for Zimbabwe using Landsat 8 OLI images. Multiple algorithms i.e. spectral indices were used to extract surface water bodies from Landsat 8 imagery. Then overall accuracies and Kappa coefficients and average reliability were then applied to assess the performance of the seven applied models. The results have shown that the LSWI plus VI can map surface water bodies with an overall accuracy of 86%, kappa statistic of 0.70 and a reliability accuracy of 89%. Comparatively, the index produced good results followed by the mNDWI which had an overall classification accuracy of 84% and an average reliability of 87%. Following on the list in terms of performance was the AWEIsh, mMDWI plus VI, NDWI and NDWI plus VI. However, other indices had slightly lower results comparatively. The study noted that LSWI plus VI applied on Landsat 8 OLI data can reliably delineate land surface water in a subtropical environment.

Phases or regimes? Revisiting NDVI trends as proxies for land degradation

Abstract: One of the main challenges in land degradation assessment is that a rigorous and systematic approach to addressing its complex dynamics is still missing. The development and application of operative tools at regional and global scales remain a challenge. Land degradation is usually defined as a long-term decline in ecosystem function and productivity. Due to its temporal and spatial resolution as well as data availability, the use of time series of spectral vegetation indexes obtained from satellite sensors has become frequent in recent studies in this field. Slope of linear trends of the normalized difference vegetation index is usually considered an accurate indicator and is widely used as a proxy for land degradation. Yet this method is built on a number of simplifying conceptual and methodological assumptions that prevent capturing more complex dynamics, such as cyclic or periodic behaviors. Our aim was to examine the limitations associated with using linear normalized difference vegetation index trends as proxies for land degradation by comparing outcomes with an alternative methodological procedure based on wavelet autoregressive methods. We explored these issues in 5 case studies from Africa and South America. We observed that trend explained a marginal portion of total temporal variability, whereas monotonic functions, such as linear trends, were unable to capture dynamics that were non-unidirectional, resulting in misinterpretation of actual trends. Wavelet autoregressive method results were encouraging as a step towards the application of more accurate methods to provide sound scientific information of land degradation and restoration.

Children's work and children's well‐being: Implications for policy

Abstract: This article argues for holistic consideration of children's work. Dominant discourse on “child labour†attends only to dangers of children's work, leading to policies that damage some children's chances for development. Far from being universally negative in children's lives, appropriate work contributes to their well†being and development, and to transitions to adulthood. Children's work can convey benefits for sustenance and quality of life, provide learning to complement and support school, offer psycho†social benefits, particularly in building self†esteem, and help develop social relations and responsibility. These benefits are especially critical for marginalized children. Common policies of abolishing child labour based on age of employment rather than potential harm deny such benefits to younger children.

Testing the capability of spectral resolution of the new multispectral sensors on detecting the severity of grey leaf spot disease in maize crop

Abstract: In this study, we tested whether GLS field symptoms on maize can be detected using hyperspectral data re-sampled to WorldView-2, Quickbird, RapidEye and Sentinel-2 resolutions. To achieve this obje...