275 research outputs found

    Scaling small-scale mechanization in the Ethiopian Highlands

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    Corrosion study of pipeline material for seabed sediment in tropical climate

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    Corrosive environments such as marine sediments can cause corrosion to steel pipelines at any time when certain conditions are met. Seabed sediment could cause severe corrosion damage due to its corrosiveness to the pipelines buried under it. Many consequences could take place in case if there is incident in oil/gas pipelines. Successfully identifying elements of corrosion in marine sediment would enhance the future of steel structure protection and monitoring systems. This article focuses on the behaviour of corrosion rate of steel located near shore environment and the aim is to determine the effect of sediment on corrosion of steel. To investigate that, simulated near shore sediment conditions have been used where the steel coupons buried in sediments which have different characteristics. Weight loss technique has been implemented to determine the weight loss rate of the steel specimens. Based on the results of this study, metal weight loss increases as the duration of exposure to seabed sediment environment become longer. The sea sediment simulated condition has given significant levels of corrosion. Conclusively, the corrosion rate of steel in seabed sediment located in tropical region is complicated and further studies are suggested

    Conservation agriculture/farmers mechanization: Africa RISING science, innovations and technologies with scaling potential from the Ethiopian Highlands

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    United States Agency for International Developmen

    Prevalence of plant-parasitic nematodes associated with tomatoes in three agro-ecological zones of Ghana

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    A study was conducted between August 2014 and May 2015 to identify plant-parasitic nematodes taxa associated with tomato (Solanum lycopersicum L.) and to assess the knowledge, perceptions and experiences of growers of the crop on occurrence and management of the parasites on their farms in nine communities within the semi-deciduous forest, the forest/savanna transitional and the savanna agro-ecological zones of Ghana. Semi-structured questionnaires were designed and administered to 54 randomly selected growers from the nine communities. Composite rhizosphere soil and tomato root samples were collected from two farms in each of the nine communities, and nematodes extracted, identified and recorded. The study revealed that many growers (73%) could not distinguish between nematode infestation, nutrient deficiency and moisture stress and, therefore, lacked knowledge on nematode control. Most of the growers (63%) continually cropped their land to tomato for periods of 4 –7 years without fallowing. All growers applied only inorganic fertilizer to their crops. Symptoms of nematode infestation were widespread in fields with high yield losses. Tomato was a host to Helicotylenchus spp. (11.5% in soil), Hoplolaimus spp. (1.0 % in soil), Meloidogyne spp. (37.4% in soil and 69.3% in roots), Pratylenchus spp. (20.6% in soil and 13.7% in roots), Rotylenchulus spp. (11.0% in soil and 12.2% in roots), Scutellonema spp. (9.5% in soil and 4.9% in roots), Tylenchus spp.(7.6% in soil) and Xiphinema spp.(1.4% in soil) across the nine communities surveyed. Semi-deciduous forest and Savanna agro-ecological zones had the highest and least population densities of nematodes, respectively. These nematodes, if not managed efficiently, could also serve as constraint to tomato production in the country

    Racial residential segregation and colorectal cancer mortality in the Mississippi Delta Region

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    INTRODUCTION: Few studies have examined the effects of racial segregation on colorectal cancer (CRC) outcomes, and none has determined whether rurality moderates the effect of racial segregation on CRC mortality. We examined whether the effect of segregation on CRC mortality varied by rurality in the Mississippi Delta Region, an economically distressed and historically segregated region of the United States. METHODS: We used data from the US Census Bureau and the 1999-2018 Surveillance, Epidemiology, and End Results (SEER) program to estimate mixed linear regression models in which CRC mortality rates among Black and White residents in Delta Region counties (N = 252) were stratified by rurality and regressed on White-Black residential segregation indices and 4 socioeconomic control variables. RESULTS: Among Black residents, CRC mortality rates in urban counties were a function of a squared segregation term (b = 162.78, P = .01), indicating that the relationship between segregation and CRC mortality was U-shaped. Among White residents, main effects of annual household income (b = 29.01, P = .04) and educational attainment (b = 34.58, P = .03) were associated with CRC mortality rates in urban counties, whereas only annual household income (b = 19.44, P = .04) was associated with CRC mortality rates in rural counties. Racial segregation was not associated with CRC mortality rates among White residents. CONCLUSION: Our county-level analysis suggests that health outcomes related to racial segregation vary by racial, contextual, and community factors. Segregated rural Black communities may feature stronger social bonds among residents than urban communities, thus increasing interpersonal support for cancer prevention and control. Future research should explore the effect of individual-level factors on colorectal cancer mortality

    A Global Survey of Infection Control and Mitigation Measures for Combating the Transmission of COVID-19 Pandemic in Buildings Under Facilities Management Services

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    Facilities management along with health care are two important aspects in controlling the spread of infectious diseases with regard to controlling the outbreak of global COVID-19 pandemic. Hence, with the increasing outbreak of COVID-19 pandemic, the importance of examining the relationship between the built environment and the outbreak of infectious diseases has become more significant. The aim of the research described in this article is to develop effective infection control and mitigation measures to prevent the transmission of COVID-19 pandemic in the built environment. This study seeks to answer the question of how the facilities management industry can help reduce the transmission of coronavirus. For this purpose, an online survey questionnaire was distributed internationally from 8 April to 25 July, 2020 to collect data from various key stakeholders. The collected data were analyzed by SPSS software. Various methods for the prevention and control of infectious diseases transmission are evaluated through this questionnaire-based survey with regard to their effectiveness for the healthy and safe built environment. These methods were categorized into three groups, including training protocols, operation and maintenance, and design and construction. The results show that all suggested methods have a positive effect on all types of buildings. These methods have an equal effect on low-risk buildings, while for high and very high-risk buildings, training protocols and design and construction measures have the greatest impact. In addition, training protocols and the measures in operation and maintenance will have the greatest effect on medium-risk buildings. The results can help in more rational decision making in relation to controlling the outbreak of COVID-19 pandemic in all types of buildings

    Investigation of Air Pollution Impact on Kinta River Water Quality at a Tropical Region

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    Critical air quality levels lead to an unhealthy environment which disrupts physical activities and human health. Wet deposition of air pollutants might cause a high concentration of water pollution due to rain water washout of nitrate and particulate matter (PM). This study aimed to investigate the impacts of air pollutants deposition on river water quality in Malaysia. The methodology involved in the analysis of secondary data (January to December 2013) for air quality and river water quality using factor, correlation, and regression. Parameters of air quality were PM10, Nitrate (NO3), ozone (O3) and temperature while water quality data were turbidity, Nitrate and PM10 (Ca, As, Hg, Cd, Cr, Pb, Zn, Cl, Fe, K, Mg, Na). The results show that there were positive correlations between air quality indicators and Kinta river water quality parameters. Correlation matrix shows that in terms of turbidity, air and water data were having 96% similarities. Regarding Nitrate concentrations, air and water records had only 30% of correlation matrix, which can be due to other sources of Nitrate which was agriculture activities near Kinta River. The factor analysis results showed that PM was the main contributor to river water quality particles with 94%. © 2020 Published under licence by IOP Publishing Ltd

    Finger vein biometric identification using discretization method

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    Over the past years, finger vein identification has gaining increasing attention in biometrics. It has many advantages as compared to other biometrics such as living-body identification, difficult to counterfeit because it resides underneath the finger skin and noninvasiveness. Finger vein feature extraction plays an important role in finger vein identification. The performance of finger vein identification is highly depending on the meaningful extracted features from feature extraction process. However, most of the works focus on how to extract the individual features and not presenting the individual characteristic of finger vein patterns with systematic representation. This paper proposed an improved scheme of finger vein feature extraction method by adopting discretization method. The extracted features will be represented systematically way in order to make classification task easier and increase the identification accuracy rate. The experimental result shows that the accuracy rate of identification of the proposed framework using Discretization is above 98.0%
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