Efficient Spin Injection into Silicon and the Role of the Schottky Barrier

Implementing spin functionalities in Si, and understanding the fundamental processes of spin injection and detection, are the main challenges in spintronics. Here we demonstrate large spin polarizations at room temperature, 34% in n-type and 10% in p-type degenerate Si bands, using a narrow Schottky and a SiO2 tunnel barrier in a direct tunneling regime. Furthermore, by increasing the width of the Schottky barrier in non-degenerate p-type Si, we observed a systematic sign reversal of the Hanle signal in the low bias regime. This dramatic change in the spin injection and detection processes with increased Schottky barrier resistance may be due to a decoupling of the spins in the interface states from the bulk band of Si, yielding a transition from a direct to a localized state assisted tunneling. Our study provides a deeper insight into the spin transport phenomenon, which should be considered for electrical spin injection into any semiconductor

Comparative Economics of Maize Grain and Seed Production in Okhaldhunga District, Nepal

Maize cultivation is the one the major farm activities among Nepalese farmers. Basically, in the rural hills of Nepal like Okhaldhunga, it dominates any other crop production. The study was conducted for comparative assessment of economics, marketing and identification of major problems of maize seed and grain production in the hilly eastern district, Okhaldhunga during June of 2017. The data were obtained through the interview of 66 producers (33 each of maize grain and seed producers) with a pre-tested semi-structured questionnaire. Descriptive statistics and parametric tests (-test, t-test) were applied. Both the grain and the seed producers were similar in terms of socio-demographic characteristics, marketing accessibilities but the seed producers were significantly benefited from the training, the extension services, credit facilities despite having 0.14 ha lesser landholding than grain producers. The inputs (manures, fertilizers and the seed) contributed 48% and 50% of the total cost incurred for grain and seed production respectively and the pre-sowing and sowing activities contributed more than 77% of cost in both cases. Despite higher cost for seed production (NRs. 24,969 more than grain production), the benefit-cost ratio of seed production was found higher (1.31) than grain production (1.05). Only 24% of the total harvest was processed and marketed as seed and using optimum quantity (66% middle portion of the cob) for seed production could further increase the income by 23.35%, the improved B:C ratio being 1.51 . The major production problems were scarce farm labor followed by lack of infrastructures while low seasonal price followed by low volume of production ranked the first and second most important marketing related problems

Does antenatal micronutrient supplementation improve children’s cognitive function? Evidence from the follow-up of a double-blind randomised controlled trial in Nepal

INTRODUCTION: Multiple Micronutrient (MMN) supplementation during pregnancy can decrease the proportion of infants born low birth weight and small for gestational age. Supplementation could also enhance children’s cognitive function by improving access to key nutrients during fetal brain development and increasing birth weight, especially in areas where undernutrition is common. We tested the hypothesis that children whose mothers received MMN supplementation during pregnancy would have higher intelligence in early adolescence compared with those receiving Iron and Folic Acid (IFA) only. METHODS: We followed up children in Nepal, whose mothers took part in a double-blind Randomised Controlled Trial (RCT) that compared the effects on birth weight and gestational duration of antenatal MMN versus IFA supplementation. We assessed children’s Full Scale Intelligence Quotient (FSIQ) using the Universal Non-verbal Intelligence Test (UNIT), and their executive function using the counting Stroop test. The parent trial was registered as ISRCTN88625934. RESULTS: We identified 813 (76%) of the 1069 children whose mothers took part in the parent trial. We found no differences in FSIQ at 12 years between MMN and IFA groups (absolute difference in means (diff): 1.25, 95% CI −0.57 to 3.06). Similarly, there were no differences in mean UNIT memory (diff: 1.41, 95% CI −0.48 to 3.30), reasoning (diff: 1.17, 95% CI −0.72 to 3.06), symbolic (diff: 0.97, 95% CI −0.67 to 2.60) or non-symbolic quotients (diff: 1.39, 95% CI −0.60 to 3.38). CONCLUSION: Our follow-up of a double-blind RCT in Nepal found no evidence of benefit from antenatal MMN compared with IFA for children’s overall intelligence and executive function at 12 years

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Not AvailableArunachal Pradesh, the largest mountainous state of India, is situated in the northeastern part of the Himalayan region and characterized by high annual rainfall, forest vegetation and diversity in soils. Information on the soils of the state is essential for scientific land use planning and sustainable production. A soil resource inventory and subsequent database creation for thematic mapping using a Geographical Information System (GIS) is presented in this paper. Physiographically, Arunachal Pradesh can be divided into four distinct zones: snow-capped mountains (5500 m amsl); lower Himalayan ranges (3500 m amsl); the sub-Himalayan Siwalik hills (700 m amsl); and the eastern Assam plains. Soils occurring in these physiographic zones are lnceptisols (37 percent), Entisols (35 per- cent), Ultisols (14 percent) and Alfisols (0.5 percent). The remaining soils can be classed as miscellaneous. Soil resource inventory studies show that the soils of the warm perhumid eastern Himalayan ecosystem, with a ‘thermic’ temperature regime, are lnceptisols and Entisols; and that they are highly acidic in nature. Soils of the warm perhumid Siwalik hill ecosystem, with a ‘hyperthermic’ temperature regime, are also Entisols and lnceptisols with a high to moderate acidic condition. The dominant soils of the northeastern Purvachal hill ecosystem, with ‘hyperthermic’ and ‘thermic’ temperature regimes, are Ultisols and Inceptisols. lnceptisols and Entisols are the dominant soils in the hot and humid plain ecosystem. Steeply sloping landform and high rainfall are mainly responsible for a high erosion hazard in the state. The soil erosion map indicates that very severe (20 percent of TGA) to severe (25 percent of TGA) soil erosion takes place in the warm per-humid zone, whereas, moderate erosion takes place in the Siwalik hills and hot, humid plain areas. This is evident from the soil depth class distribution of Arunachal Pradesh, which shows that shallow soils cover 20 percent of the TGA of the state. Most of the the state is covered by hills and agri- cultural practices are limited to valley regions, However, the soils of other physiographic zones (lower altitudinal, moderately hilly terrain) provide scope for plantations, such as orange, banana and tea plantations.Not Availabl

Tracking health system performance in times of crisis using routine health data: lessons learned from a multicountry consortium

COVID-19 has prompted the use of readily available administrative data to track health system performance in times of crisis and to monitor disruptions in essential healthcare services. In this commentary we describe our experience working with these data and lessons learned across countries. Since April 2020, the Quality Evidence for Health System Transformation (QuEST) network has used administrative data and routine health information systems (RHIS) to assess health system performance during COVID-19 in Chile, Ethiopia, Ghana, Haiti, Lao People's Democratic Republic, Mexico, Nepal, South Africa, Republic of Korea and Thailand. We compiled a large set of indicators related to common health conditions for the purpose of multicountry comparisons. The study compiled 73 indicators. A total of 43% of the indicators compiled pertained to reproductive, maternal, newborn and child health (RMNCH). Only 12% of the indicators were related to hypertension, diabetes or cancer care. We also found few indicators related to mental health services and outcomes within these data systems. Moreover, 72% of the indicators compiled were related to volume of services delivered, 18% to health outcomes and only 10% to the quality of processes of care. While several datasets were complete or near-complete censuses of all health facilities in the country, others excluded some facility types or population groups. In some countries, RHIS did not capture services delivered through non-visit or nonconventional care during COVID-19, such as telemedicine. We propose the following recommendations to improve the analysis of administrative and RHIS data to track health system performance in times of crisis: ensure the scope of health conditions covered is aligned with the burden of disease, increase the number of indicators related to quality of care and health outcomes; incorporate data on nonconventional care such as telehealth; continue improving data quality and expand reporting from private sector facilities; move towards collecting patient-level data through electronic health records to facilitate quality-of-care assessment and equity analyses; implement more resilient and standardized health information technologies; reduce delays and loosen restrictions for researchers to access the data; complement routine data with patient-reported data; and employ mixed methods to better understand the underlying causes of service disruptions

Evaluation of the Delivery of a Live Attenuated Porcine Reproductive and Respiratory Syndrome Virus as a Unit Solid Dose Injectable Vaccine

Solid dose vaccine formulation and delivery systems offer potential advantages over traditional liquid vaccine formulations. In addition to enhanced thermostability, needle-free delivery of unit solid dose injectable (USDI) vaccines offers safe, rapid, and error-free administration, with applicability to both human and animal health. Solid dose formulation technologies can be adapted for delivery of different vaccine formats including live attenuated vaccines, which remain the 'gold standard' for many disease targets. Porcine reproductive and respiratory syndrome viruses (PRRSV) cause one of the most economically important diseases affecting the global pig industry. Despite several shortcomings, live attenuated vaccines are widely used to control PRRSV. We optimised a freeze-dried USDI formulation of live attenuated PRRSV-1, which fully retained infectious titre, and evaluated its immunogenicity in comparison to virus delivered in liquid suspension via intramuscular and subcutaneous needle inoculation. Pigs vaccinated with the USDI formulation displayed vaccine viraemia, and PRRSV-specific antibody and T cell responses comparable to animals immunised with the liquid vaccine. The USDI vaccine formulation was stable for at least 6 months when stored refrigerated. These data demonstrate the potential for a solid dose vaccine delivery system as an alternative to conventional needle-syringe delivery of live attenuated PRRSV vaccines.Peer reviewe