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The potential impacts of climate change on the food security of subsistence farmers is a serious concern. This article explores the food security situations of two categories of subsistence farm households, vegetable- and cereal-based farming systems, in the Makwanpur district of Nepal in the context of climate change. Local climate data for the past 30 years were analyzed. Interviews with local farmers and key informants, and focus group discussions were carried out to collect the primary data. Empirical data showed that changes in climate variables for the study period were in line with farmers’ perceptions and that farming communities were negatively impacted. Perceived impacts were erratic rainfall, increased frequency of floods and droughts, soil degradation and insect pests, weeds and diseases. Farmers have modified traditional cropping patterns and calendar, changed crop varieties and increased fertilizer and pesticide applications in order to maintain crop yields. They have also sought off-farm employment. However, agricultural productivity in the area is declining and only one third of all households in the area were food secure. Household food insecurity was at mild to moderate levels, but vegetable-based households were more secure than cereal-based ones. At the household level, locally successful adaptive measures, such as rainwater harvesting, mulching, planting date adjustments, off-farm opportunities, including infrastructure and extension support, could increase production and contribute to reversing the impact of increased risk attributed to climate change. 相似文献
23.
Purna C. Rath Laxmidhar Besra Bimal P. Singh Sarama Bhattacharjee 《Ceramics International》2012,38(4):3209-3216
Titania–hydroxyapatite (HAp) bi-layer coating on Ti metal substrate with improved adhesion strength is fabricated by a simple two step processes: electrodeposition of Ti sol and electrophoretic deposition of HAp powder, followed by heat treatment at 800 °C. At optimized process parameters, the bi-layer developed consists of dense, thin and crystalline titania interlayer with porous, thick and crystalline HAp top layer. The heat treatment of bi-layer coating allows elemental intermixing at the interface of TiO2 and HAp, as determined by energy dispersive X-ray spectroscopy (EDX) and Raman spectra analysis. Compared to monolithic HAp coating, the TiO2/HAp bi-layer coating shows significant enhancement in the adhesion strength (48 MPa) as well as corrosion resistance without compromising its biocompatibility. The steep increase in adhesion strength is believed to be due to mechanical interlocking and diffusion bonding at the interface. Presence of dense titania interlayer in the bi-layer coating reduces the corrosion current in Ringer's solution to a negligible value (~100 nA). 相似文献
24.
Yuwei Liu Kemin Mao Nan Zhang Bimal Chitrakar Pimiao Huang Xianghong Wang Bing Yang Yaxin Sang 《Journal of food science》2022,87(5):2034-2047
25.
S S Shinde K M Jadhav G K Bichile Bimal S Trivedi R G Kulkarni 《Bulletin of Materials Science》1998,21(5):409-413
The structural and magnetic properties of the mixed spinel Co1+x Si x Fe2?2x O4 system for 0·1≤x≤0·6 have been studied by means of X-ray diffraction, magnetization, and Mössbauer spectroscopy measurements. X-ray intensity calculations indicate that Si4+ ions occupy only tetrahedral (A) sites replacing Fe3+ ions, and the added Co2+ ions substitute for (B) site Fe3+ ions. The Mössbauer spectra at 300 K have been fitted with two sextets in the ferrimagnetic state corresponding to Fe3+ at the A and B sites, forx≤0·3. The Mössbauer intensity data shows that Si possesses a preference for the A site of the spinel. The variation of the saturation magnetic moment per formula unit measured at 300 K with the Si content, is explained on the basis of Neel’s collinear spin ordering model forx≤0·3 which is supported by Mössbauer, and X-ray data. The Curie temperature decreases nearly linearly with increase of the Si content, forx=0·1–0·6. 相似文献
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The Hindu Kush Himalayas are called the water towers of Asia as they are the source of 10 major rivers and have the largest snow and ice deposits outside the two poles. Water emanating from the HKH provides food, energy and ecosystem services to up to 1.3 billion people. Climate change and socio-economic and demographic changes have put unprecedented pressure on these water resources, leading to uncertain supplies, increased demands and higher risks of extreme events like floods and droughts. The eight articles in this special issue highlight various dimensions of the Himalayan water resources by focusing on both physical and social science aspects of water management. 相似文献
28.
Jiemin Zhang April Webster Michael Lawrence Madhav Nepal Rachel Pottinger Sheryl Staub-French Melanie Tory 《Information Systems》2011
Due to the development of XML and other data models such as OWL and RDF, sharing data is an increasingly common task since these data models allow simple syntactic translation of data between applications. However, in order for data to be shared semantically, there must be a way to ensure that concepts are the same. One approach is to employ commonly usedschemas—called standard schemas —which help guarantee that syntactically identical objects have semantically similar meanings. As a result of the spread of data sharing, there has been widespread adoption of standard schemas in a broad range of disciplines and for a wide variety of applications within a very short period of time. However, standard schemas are still in their infancy and have not yet matured or been thoroughly evaluated. It is imperative that the data management research community takes a closer look at how well these standard schemas have fared in real-world applications to identify not only their advantages, but also the operational challenges that real users face. 相似文献
29.
Railway Engineering Science - Unbound granular material specifications for road pavements in Australia are primarily based on physical material specification rather than mechanical... 相似文献
30.
Hyun Young Kil Eun Soo Seong Bimal Kumar Ghimire Ill-Min Chung Soon Sung Kwon Eun Jeong Goh Kweon Heo Myong Jo Kim Jung Dae Lim Dokyoung Lee Chang Yeon Yu 《Food chemistry》2009
Here, we report the antioxidant and antimicrobial activities of sorghum (Sorghum bicolor Moench) extracts prepared from 25 cultivars from South Korea. Four cultivars of sorghum were extracted with methanol, then further fractioned with n-hexane, ethyl acetate, n-butanol, and water. The RC50 (the concentration of antioxidant required to achieve absorbance equal to 50% that of a control containing no antioxidants) value of the DPPH method and reducing power showed higher efficiency in the BuOH layer of all selected cultivars except Neulsusu. The various fractions were then examined for antimicrobial activity by a serial two fold dilution assays using the paper disc method. The methanol extracts showed higher levels of antimicrobial activity than the other fractions. Our results indicate that sorghum extracts could be used as a source of antioxidant and antimicrobial ingredients in the food industry. 相似文献