Domestic use of biomass fuel in the rural Meghna floodplain areas of Bangladesh

Rural households in the developing countries constitute the largest share of the biomass fuel consumption. It is also a major source of energy in the low income country. However, this energy consumption pattern varies from region to region. Different case studies on the biomass fuel consumption will certainly contribute to the understanding on the energy uses of a nation. The present study was conducted in the rural areas of the Meghna floodplain zone in Bangladesh, with a total of 80 sampled households, using the stratified random sampling technique through the semi-structured questionnaires from November 2008 through February 2009. Firewood, cowdung, leaves and twigs, branches, rice straw and rice husk were used as the biomass fuels mainly for the cooking purpose. Leaves and twigs were found as the dominant biomass fuel as 187 +/- 25.69 (SE) kg month(-1) household(-1). The major source of biomass fuel collection was identified as the own homestead and agricultural lands, 74%. The households spent 14.56 +/- 8.94 US$ month(-1) household(-1) for biomass fuels. The ratio of the total energy expenditure to the total income of the household was around 11%. But, the ratio of the biomass expenditure to the total energy expenditure of the households was 68%. Monthly income, land ownership and family size were found significantly influencing to the biomass energy expenditure. The study will be useful for the policy makers in the renewable energy, forestry and agriculture sector in Bangladesh.ArticleIFOREST-BIOGEOSCIENCES AND FORESTRY. 3:144-149 (2010)journal articl

Shifting Cultivation and its Alternatives in Bangladesh: Productivity, Risk and Discount Rates

This study evaluates the economic feasibility of replacing shifting cultivation (Jhum) with settled agriculture and new soil conservation technology based on an assessment of the farmers’ risk and corresponding discount rates in the Khagrachari hill district of Bangladesh. Shifting cultivation can cause top soil loss, degradation of soil quality, and decrease in crop yield but significant improvements in yields could also be achieved with increased fallowing. On the other hand, the use of soil conservation technology is found to be highly profitable. The study finds that the social discount rate is a crucial factor determining the switch from shifting cultivation to new soil conservation methods. Jhum farmers are likely to switch to the new technology in a 3-year rotation scheme only if their rate of discount is below 58%. On the other hand, farmers with a 6- year rotation would switch as long as their discount rate is less 33%. Because they discount the future rather heavily, poor farmers with short fallows would require very high returns to tempt them to adopt a new type of farming. High initial cost of establishment, long gestation period, and unclear customary rights are additional deterrents to the adoption of soil conservation technology. The study concludes that these problems can be overcome if financial support and technical assistance are made available

Electricity Production by Microbial Fuel Cell Using Cheese Whey Wastewater of the Dairy Industry in Rajshahi, Bangladesh

Microbial fuel cell is an alternative technology for energy generation aiming to recover chemical energy from biodegradable wastewater to and convert it to electricity. In this study, a small laboratory-scale microbial fuel cell was evaluated to generate electricity using cheese whey wastewater as the sole nutrient source. The open-circuit potential and the stable voltage output with 1000 Ω external resistance of the fuel cell using only cheese whey wastewater as anolyte were 0.925 V and 0.379 V, respectively. The power density achieved by the cell was 7.18 mW m–2, with a maximum current density of 35.75 mA m–2. The series connection of seven fuel cells produced the open-circuit potential of 7 V that could run a 4 V LED light strip for more than 3 hours. Cheese whey-microbial fuel cell can be considered as a cost-effective renewable energy source for the operation of low energy demanding devices in the future. This work is licensed under a Creative Commons Attribution 4.0 International License

Locating NAPLs in Ground Water Using Partitioning Fluorescent Dyes

A major challenge in ground water remediation is locating nonaqueous phase liquids (NAPLs). Partitioning tracers can be used to identify NAPL sources between injection and extraction wells. NAPLs are only slightly soluble in water, pose a long-term source of groundwater contamination, and can be difficult to remove. The complexity of recovery processes requires the development of new technologies that guarantee cost effective methods for locating and quantifying NAPLs. Traditional methods like soil coring have been inefficient since they underestimate the quantity of NAPLs and are expensive. Partitioning tracer tests are some of the most recent methods developed for locating these contaminants and determining the volume of the NAPL present in the inter-well zone. The results of the tests can be used to develop remediation techniques to recover NAPLs entrapped in the contaminated zone. Fluorescent dyes may be useful as partitioning tracers. They can be analyzed quickly at the field site, resulting in a shorter analysis time and lower costs than other partitioning tracers. This project pursued the selection of suitable tracers and the development of partitioning tracer techniques to locate and quantify NAPLs in the subsurface

Yields gap evaluation of wheat grown in Piedmont plain and Floodplain soils of Bangladesh through compositional nutrient diagnosis (CND) norm

Mineralnutrient stress is one of the major yield gap factors, especially in floodplain and piedmont plain soil. The compositional nutrient diagnosis (CND) provides a plant nutrient imbalance index in statistical distribution patterns, which is important for adjusting the soil-plant systems specific fertilization for maintaining sustainable soil fertility. This study calculated the CND norms of wheat (Triticum aestivum L.) and identified optimum wheat yield target of high-yielding subpopulation in farmers' fields. It also categorized the most yield limiting nutrient(s) for wheat grown. Popular high-yielding wheat was grown in 62 farmers' fields, maintaining farmers' nutrient management plan (FP) and improved nutrient management plan (INM). Nutrient composition analysis was done from 62 young foliar composite samples, collected at 7th leaves stage (vegetative stage).The CND generic model gave 3.47 Mg ha–1 as minimum cutoff yield of the high-yield subpopulation. Nitrogen was identified as the core yield limiting nutrient for wheat in piedmont and floodplain soils. However, the yield limiting nutrients for wheat grown in the studied are were established the following series: N > S > K, Mg >P, Ca and Mn >Fe >B >Zn respectively. The CND generic model, allowed us to suggest thatN, P, K, Mn, B were the factors discriminating high- from low–yielding subpopulation in piedmont plain and floodplain soils of Bangladesh

Contact transmission of influenza virus between ferrets imposes a looser bottleneck than respiratory droplet transmission allowing propagation of antiviral resistance

Influenza viruses cause annual seasonal epidemics and occasional pandemics. It is important to elucidate the stringency of bottlenecks during transmission to shed light on mechanisms that underlie the evolution and propagation of antigenic drift, host range switching or drug resistance. The virus spreads between people by different routes, including through the air in droplets and aerosols, and by direct contact. By housing ferrets under different conditions, it is possible to mimic various routes of transmission. Here, we inoculated donor animals with a mixture of two viruses whose genomes differed by one or two reverse engineered synonymous mutations, and measured the transmission of the mixture to exposed sentinel animals. Transmission through the air imposed a tight bottleneck since most recipient animals became infected by only one virus. In contrast, a direct contact transmission chain propagated a mixture of viruses suggesting the dose transferred by this route was higher. From animals with a mixed infection of viruses that were resistant and sensitive to the antiviral drug oseltamivir, resistance was propagated through contact transmission but not by air. These data imply that transmission events with a looser bottleneck can propagate minority variants and may be an important route for influenza evolution

Improving Traffic Density Forecasting in Intelligent Transportation Systems Using Gated Graph Neural Networks

This study delves into the application of graph neural networks in the realm of traffic forecasting, a crucial facet of intelligent transportation systems. Accurate traffic predictions are vital for functions like trip planning, traffic control, and vehicle routing in such systems. Three prominent GNN architectures Graph Convolutional Networks (Graph Sample and Aggregation) and Gated Graph Neural Networks are explored within the context of traffic prediction. Each architecture's methodology is thoroughly examined, including layer configurations, activation functions,and hyperparameters. The primary goal is to minimize prediction errors, with GGNNs emerging as the most effective choice among the three models. The research outlines outcomes for each architecture, elucidating their predictive performance through root mean squared error and mean absolute error (MAE). Hypothetical results reveal intriguing insights: GCNs display an RMSE of 9.10 and an MAE of 8.00, while GraphSAGE shows improvement with an RMSE of 8.3 and an MAE of 7.5. Gated Graph Neural Networks (GGNNs) exhibit the lowest RMSE at 9.15 and an impressive MAE of 7.1, positioning them as the frontrunner

Experimental Study on the Explosive Spalling in High-Performance Concrete: Role of Aggregate and Fiber Types

A complete description of the mechanical behavior of High-Performance Concrete in fire still requires further efforts to fully understand the tricky phenomenon of spalling, whose complexity comes from the interaction among different phenomena, namely: the microstructural changes occurring in concrete at high temperature, the pressure rising in the pores, and the stress induced by both thermal gradients and external loads. To what extent these different aspects influence each other is still not completely clear, and within this context a comprehensive experimental campaign has been launched at the Politecnico di Milano, focusing on the role played by concrete grade, aggregate type, and fiber type and content. Eleven concrete mixes are investigated considering three grades (fc ≥ 40, 60 and 90 MPa), three aggregate types (silico-calcareous, basalt and calcareous aggregates) and different fiber types and contents (steel and monofilament or fibrillated polypropylene fibers)

Challenges of Single Motherhood in Socio-Cultural Context: A Qualitative Study in Rural areas of Bangladesh

The growing number of divorces and separations induces the frequency of single mothers facing challenges in the mainstream socio-economic realities in Bangladesh. Past studies focused on structural aspects, economic hardship, and psychological issues of single mothers, mainly in the urban context. Nevertheless, the challenges in rural settings vary from urban single motherhood, and this aspect remains understudied. This qualitative narrative aims to analyse the challenges of single mothers in rural settings in Bangladesh. Twenty-eight in-depth interviews and ten key informant interviews were conducted using semi-structured interview guidelines. Thematic analysis identified four major themes of the rural single mothers’ challenges, social, economic, cultural, and psychological, leading a single mother to become dependent on other family members or relatives. The underlying factor of the challenges was the deprivation of property, patriarchal social structure, and social stigma. Rural single mothers face more complex challenges than urban ones because of the lack of income opportunities, insecurity, and self-dependencies. Findings will contribute to recommending and formulating a policy for the single mother considering the local realities of the rural single mothers in Bangladesh.