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Community livelihoods within the Vietnamese Mekong Delta are at risk from droughts and saltwater intrusion. This study used the DFID sustainable livelihoods framework in a multi-disciplinary method to formulate a competent analysis and methodology for the evaluationof the sustainability, vulnerability, and adaptation of the coastal residents' livelihood. A review of the local records coupled with a survey of community representatives from 120 households highlights the increase in temperature and rainfall frequency as well as the occurrence of drought and salinity intrusion in many places along the coastal zones. The study analyzed five capital resources of farmers wherein differences in these resources--before, during, and after the drought-saltwater intrusion events--were compared. Results showed that these resources were vulnerable at different levels due to the impacts of drought and salinity intrusion. Furthermore, there were distinct differences in the indices over time. Notably, the migration of young workers from the sites opened up employment for the older workers who did not migrate. Land ownership varied among households, with more than half of respondents either planting two rice crops or raising shrimp, traditional farming models in the sites. Although the farmers ably purchased some necessary inputs for production, their physical capital was limited to the bare necessities for production and daily subsistence. Financially, the droughtsalinity disaster affected the farmers negatively, so they sought loans mostly from informal sources. However, even the least affected farmers also sought loans but for purposes other than production. Social capital improved with the disaster because social organizations and local governments became more involved with the communities. However, no further improvement was observed in the years after the disaster. Overall, Nam Chanh hamlet is slightly more vulnerable to drought-saltwater intrusion (LVI = 0.452) than Soc Leo hamlet (LVI = 0.414) because of the greater vulnerability of its human, physical, and financial capitals, as well as the less diverse livelihood strategies. The results from this study will provide valuable insight into the livelihood vulnerability of coastal communities, specifically to drought and salinity intrusion. Further, results can contribute to the knowledge that enables scientists, decision makers, and governments to determine appropriate responses to similar situations and to consider policy for land and water management in coastal communities. [ABSTRACT FROM AUTHOR]

This work explores numerically the short-channel effects in thin-body SOI MOSFETs with shallow source/drain architecture, where the junction depths are less than the associated silicon body thicknesses. Unique fringing field and short-channel behavior are observed in the unconventional SOI devices. Numerical results of the short-channel effects are compared with those in the conventional SOI MOSFETs. For given silicon body thicknesses, the shallow junction SOI devices exhibit the superior short-channel immunity over the conventional counterparts.

Tunnel field-effect transistor (TFET) has served as one of the most attractive candidates for use in future low-power integrated circuits. To explore the current-voltage characteristics of TFET devices, the Kane's tunnel model has been widely used in numerical simulations and physical models to predict the tunneling current produced in the TFETs. This study examines the proper calculations of Kane's model parameters appropriate for the indirect band-to-band tunneling generated in compressively strained Si 1−x Ge x channel on Si-substrate. The calculated parameters were verified with the measured results from experimental TFETs. Good agreements are confirmed between the numerical and measured data without any fitting factors.

Floods are a familiar and frequent feature of life in the Vietnamese Mekong River Delta (MRD). Although floods bring hardship to people, they also bring benefits, such as livelihood development. People in the MRD have experienced the impacts of floods for years, however some adapt well to the floods, while others are more vulnerable. Studying resilience to floods is useful as a way of assessing the capacity of rural households to cope with, and benefit from, annual floods. Social capital plays an important role in a household’s ability to access technical information, resources and local knowledge during annual flooding. Livelihood diversity is known to be a vital strategy for coping with the risks of flood damage. However little is known about the effects of social capital and livelihood diversity on household resilience to floods in terms of securing their homes, securing food, and protecting income, as well as learning new flood-based livelihoods. This study explores the relationship between a household’s resilience to floods in the MRD and levels of social capital (neighbourhood attachment, social supportive network, and participation in groups and associations) and livelihood diversification. These different forms of social capital were measured using the Inverse Herfindahl-Hirschman Index (IHHD). Resilience in this context is defined as the ability of households to learn from, cope with, and benefit from, flood events. Household resilience was measured using expected levels of well-being, obtained from a household survey in 2010, using a five-point Likert scale to construct indexes of household resilience. The results from multiple regressions demonstrate that different forms of social capital have different effects on different forms of household resilience. Neighbourhood attachment has statistically significant effects on a household’s ability to secure food, income, and a level of interest in learning new flood-based livelihoods, but it does not have a significant effect on the capacity of households to secure their home. Similarly, the social supportive network index has significant effects on a household’s ability to learn new livelihoods during the flood season, but it does not have a significant effect on household capacity to secure the home, food and income. Besides social capital, the socio-economic condition of households (household income) is shown to have a significant effect on the three resilience factors – capacity to secure homes, secure food and income, and level of interest in learning and engaging in new livelihoods. Rich households are less likely to be interested in learning new livelihoods (negative effect). Rich households often own large areas of land so they are more likely to specialize in rice farming, which takes a break during the flood season. Poor and medium-income households often own less land or are landless, so they have to work harder to secure an income and food in order to survive during the flood season. Other socio-economic variables, such as the gender and age of respondents, have significant effect on the level of interest shown in learning new livelihoods (negative effect). Housing type also has a significant effect on household capacity to secure the home (concrete houses are less vulnerable). Regional flood factors also have a significant effect on the three resilience factors; people in the highest flood-prone region are less likely to be resilient in terms of securing their houses, food and income, but are more likely to learn new ways of living with floods. Surprisingly, the livelihood diversity index has no effect on household resilience to floods in this context.

Climate change has brought enormous challenges to human lives, livelihoods, and the environment. Temperature increase, abnormal floods, and water pollution have negatively impacted on socioeconomic and agricultural systems in the Vietnamese Mekong delta. The aims of this study are to assess the readiness of traditional rice farming systems in the Vietnamese Mekong delta in adapting to climate change conditions and select traditional rice genetic materials for supporting breeding programs in the future. The research was conducted from April 2016 to December 2017 in the upper part of the Vietnamese Mekong delta, including An Giang, Kien Giang, and Long An provinces where the cultivation of traditional rice varieties or TRV thrive with the conditions brought by the climate change such as drought and salinity. Social research methods were used to assess farmers' socioeconomic status, indigenous farming knowledge, and the alternative farming models in the context of climate change. Sampling seeds were also analyzed based on morphological and yield-related indicators. TRVs are distributed mainly in Kien Giang and Long An provinces and some mountainous areas of Tri Ton district in An Giang province. Yield varies from four to seventh and these rice varieties are well adapted to unfavorable soil and adverse weather conditions such as drought, salinity, and alum toxicity. These rice varieties can tolerate a submergence of <1.0 m while possessing outstanding features such as good resistance to common pests, albeit long growing duration, less fertilizer, demand, and pleasant taste. TRV is combined with aquaculture farming in Kien Giang, providing a reliable source of organic food essential for aquatic organisms. TRVs are also providing potential condition for farmers to develop vegetable crops, particularly in An Giang and Long An provinces. However, TRV farming areas have significantly decreased owing to the rapid development of irrigation schemes for intensively highyielding rice varieties production. Therefore, indigenous seed stock in the research sites has been alarmingly decreasing, some traditional rice varieties even disappeared, calling for studies on the restoration and conservation of these varieties. The research further showed that there was a rich diversity in TRVs in terms of color, phenotypes, and quality--providing genetic resources for further research, especially for climate-resilient rice breeding programs. TRV is a potential replacement for the intensive third rice cropping during flooding season inside the high dike systems. This alternative helps to reduce soil and water pollution, preserve freshwater during flooding seasons, and adapt to environmental changes in the Vietnamese Mekong delta. The key findings of this research are going to be presented in various academic conferences and field meetings, to attract agricultural policymakers and other stakeholders for further research and development of TRV farming models. [ABSTRACT FROM AUTHOR]

Mountainous black-bone chickens are characterized by black bones, meat and skin meat from black-bone chickens has been preferred by consumers. Conservation of mountainous black-bone chickens is one way to maintain the animal bio-diversity for H¿mong minority group in the northern mountainous provinces. From the original generation consisted of 200 females and 30 males selected from Xin Man and Dong Van, the first generation was established. From the first generation, a breeding flock consisted 773 birds in 30 households was established. The body weight of hens and cocks at 20 weeks old was 1,266 - 1,218.66 and 1,706.33 - 1,720.67 g, respectively. Selection by feather phenotypes showed that there was a difference in the growth rate among three feather phenotypes. The body weight at one day old of the black, white and striped feather chicken, which was 36.33, 32.70 and 30.07 g, respectively, was not significantly different. However, the body weight at 20 weeks old of the black, white and striped feather chicken, which was 1505.70, 1114.00, 612.10 and 1480.90 g, respectively.