28 research outputs found

    Joint quality enhancement of AA6061-T6 friction stir weldment by reinforcing with pulverized glass waste using different reinforcement strategies

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    The joint quality performance of AA6061-T651 friction stir weldments had been investigated in this study through addition of pulverized waste glass (PWG), palm kernel shell ash (PKSA) and synthetic silicon carbide (SSC) with a bid to enhancing some selected mechanical properties. Optimized processing parameters which include 1120 rpm rotational speed, 40 mm/min traverse speed, 1.5o tilt angle) and optimum reinforcement strategy (parallel hole) established from a preliminary investigation were utilized for the friction stir welding. The mechanical properties such as the tensile strength, hardness and impact energy were then further investigated. The results showed that the mechanical properties of all the reinforced welded joints improved significantly than the unreinforced joint having a relatively reduced joint performance of 132 MPa tensile strength, hardness of 45.3 HRB and impact energy of 39.4 J. The PWG-reinforced friction stir welded joint performed optimally at a tensile strength of 212.7 MPa, 72 HRB hardness and 54.5 J impact energy followed by the SSC-reinforced joint which exhibited 173.7 MPa tensile strength, 54.8 HRB hardness and impact energy of 41.7 J. Hence, 80%, 59% and 38% joint performance was exhibited through tensile strength, hardness and impact energy of PWG-reinforced friction stir weldments of AA6061-T651 against the unreinforced weldments

    Mapping local patterns of childhood overweight and wasting in low- and middle-income countries between 2000 and 2017

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    A double burden of malnutrition occurs when individuals, household members or communities experience both undernutrition and overweight. Here, we show geospatial estimates of overweight and wasting prevalence among children under 5 years of age in 105 low- and middle-income countries (LMICs) from 2000 to 2017 and aggregate these to policy-relevant administrative units. Wasting decreased overall across LMICs between 2000 and 2017, from 8.4 (62.3 (55.1�70.8) million) to 6.4 (58.3 (47.6�70.7) million), but is predicted to remain above the World Health Organization�s Global Nutrition Target of <5 in over half of LMICs by 2025. Prevalence of overweight increased from 5.2 (30 (22.8�38.5) million) in 2000 to 6.0 (55.5 (44.8�67.9) million) children aged under 5 years in 2017. Areas most affected by double burden of malnutrition were located in Indonesia, Thailand, southeastern China, Botswana, Cameroon and central Nigeria. Our estimates provide a new perspective to researchers, policy makers and public health agencies in their efforts to address this global childhood syndemic. © 2020, The Author(s)

    Author Correction: Mapping local patterns of childhood overweight and wasting in low- and middle-income countries between 2000 and 2017 (Nature Medicine, (2020), 26, 5, (750-759), 10.1038/s41591-020-0807-6)

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    An amendment to this paper has been published and can be accessed via a link at the top of the paper. © 2020, The Author(s)

    Author Correction: Mapping local patterns of childhood overweight and wasting in low- and middle-income countries between 2000 and 2017 (Nature Medicine, (2020), 26, 5, (750-759), 10.1038/s41591-020-0807-6)

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    An amendment to this paper has been published and can be accessed via a link at the top of the paper. © 2020, The Author(s)

    Effect of soil conservation on productivity and food security on maize farmers in northwest Nigeria

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    IITA supervisor: Dr. Kamara, A.The adoption of soil conservation practices is important for sustaining Nigerian agriculture where smallholder maize farmers face constraints such as low soil fertility that lead to low productivity and food insecurity. This study aims to analyze the effect of soil conservation on productivity and food security of maize farmers in Northwest Nigeria. The study used a two year panel data of 792 maize farmers for 2016 and 2017 cropping seasons, collected by IITA under “Taking Maize Agronomy to Scale in Africa (TAMASA)” project implementation in Nigeria. Descriptive statistics, pooled multivariate probit, random-effects ordered probit model, and fixed-effect regression were used to analyze the data collected. Result revealed that the average age of farmers was 44 years, average household size was 9 persons, average farming experience was 19 years, 75% of the farmers had no extension contact, 77% had no access to credit, 69% belong to no association, 81% had no access to maize contract farming, average livestock owned was 2.14 units, and average farm size was 3.23 hectares. Result showed that animal manure had the highest rate of adoption with 76% and 69% adoption rate in 2016 and 2017 cropping seasons respectively. There is significant correlation between soil conservation practices, suggesting that adoptions of the practices are interrelated. The unconditional and conditional probabilities of soil conservation practices revealed the existence of possible complementarities and substitutability among the practices. Majority of the farmers combined the adoption of two practices with adoption rates of 33% and 29% in 2016 and 2017 cropping seasons respectively, of which the combination of animal manure and crop residue retention was the major combined practices with 58% and 35% adoption rate in 2016 and 2017 cropping seasons respectively. Result showed that adoption of soil conservation practices was significantly influenced by factors such as age of household head, access to maize contract farming, livestock ownership, farming experience, access to off-farm income, access to credit, inorganic fertilizer, periods of weeding, and amount of rainfall. Also, the intensity of adoption of soil conservation practices were significantly influenced by factors such as access to maize contract farming, livestock ownership, farm size, access to off-farm income, inorganic fertilizer, periods of weeding, and amount of rainfall. The fixed effect regression result showed that practicing organic manure had significant effect on maize productivity and households’ food security

    Statistical examination of the aerosols loading over Kano-Nigeria: the satellite observation analysis

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    Statistical examination of the aerosols loading over Kano – Nigeria: the Satellite observation analysis. The problem of underestimating or overestimating the aerosols loading over Kano is readily becoming a global challenge. Recent health outcomes from an extensive effect of aerosols pollution has started manifesting in Kano. The aim of the research is to estimate the aerosols loading and retention over Kano. Thirteen years aerosol optical depth (AOD) data was obtained from the Multi-angle imaging spectroradiometer (MISR). Statistical tools, as well as analytically derived model for aerosols loading were used to obtain the aerosols retention and loading over the area. It was discovered that the average aerosols retention over Kano is 4.9%. The atmospheric constants over Kano were documented. Due to the volume of aerosols over Kano, it is necessary to change the ITU model which relates to signal budgeting

    Towards Inclusive Diagnostics for Neglected Tropical Diseases:: User Experience of a New Digital Diagnostic Device in Low-Income Settings

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    Designing new and inclusive diagnostic tools to detect Neglected Tropical Diseases (NTDs) to achieve rational disease control requires a co-design process where end-users’ input is important. Failure to involve all potential end-users in new diagnostics for NTDs can result in low use and adoption failure, leading to persistent infection hot spots and ineffective disease control. There are different categories of potential end-users of new diagnostic tools for NTD control, and it is unclear if there are differences between the user efficiency, effectiveness, perception, and acceptability across these end-user categories. This study evaluated the usability, user perception, contextual factors affecting the user’s experience, and acceptability of a new digital optical diagnostic device for NTDs across three types of potential end users. A total of 21 participants were tested. Laboratory scientists, technicians, and Community Health Extension Workers (CHEWs) in training achieved similar scores on the usability and user perception questionnaires with no statistically significant difference between end-user categories. All participants also have high scores for the user perception domains which strongly correlate with the acceptability of the AiDx NTDx Assist device. This study indicates that, by providing digital diagnostic tools in combination with minimal training and support, CHEWs undergoing training and, by extension, CHEWs post-training, can be involved in the diagnoses of NTDs, potentially enhancing a community’s capabilities to diagnose, treat, and control NTDs

    Target product profiles for devices to diagnose urinary schistosomiasis in Nigeria

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    Schistosomiasis is a treatable and preventable neglected tropical disease of Public Health importance affecting over 200 million people worldwide while Nigeria is one of the high burden countries. Currently, available diagnostic tests are cumbersome, low in sensitivity and not field-adaptable given the high skills required that are not available in the rural settings where the diseases are majorly prevalent. There is an urgent need for an easy to use automated diagnostic device to replace the current gold standard, the human-operated microscope. Many promising automated diagnostic technologies are under development. However, a good understanding of the real needs within the local healthcare context is crucial in order to develop and implement a new health diagnostic device. Too often, there is a mismatch between what is needed and what is developed. A target product profile can guide the R&amp;D process in matching with the needs in the local healthcare context. The goal of this project is to combine gaps in the healthcare system and needs from stakeholders with technological possibilities in order to develop a target product profile for a diagnostic device for S. haematobium for specific healthcare scenarios in Nigeria

    Target product profiles for devices to diagnose urinary schistosomiasis in Nigeria

    No full text
    Schistosomiasis is a treatable and preventable neglected tropical disease of Public Health importance affecting over 200 million people worldwide while Nigeria is one of the high burden countries. Currently, available diagnostic tests are cumbersome, low in sensitivity and not field-adaptable given the high skills required that are not available in the rural settings where the diseases are majorly prevalent. There is an urgent need for an easy to use automated diagnostic device to replace the current gold standard, the human-operated microscope. Many promising automated diagnostic technologies are under development. However, a good understanding of the real needs within the local healthcare context is crucial in order to develop and implement a new health diagnostic device. Too often, there is a mismatch between what is needed and what is developed. A target product profile can guide the R&amp;D process in matching with the needs in the local healthcare context. The goal of this project is to combine gaps in the healthcare system and needs from stakeholders with technological possibilities in order to develop a target product profile for a diagnostic device for S. haematobium for specific healthcare scenarios in Nigeria.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Design for SustainabilityNumerics for Control & Identificatio
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