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Soil infertility is the main barrier to dryland agricultural production in China. To provide a basis for the establishment of a soil amelioration technical system for rainfed fields in the semiarid area of northwest China, we conducted a four—year (2007–2011) field experiment to determine the effects of wheat straw incorporation on the arid soil nutrient levels of cropland cultivated with winter wheat after different straw incorporation levels. Three wheat straw incorporation levels were tested (H: 9000 kg hm-2, M: 6000 kg hm-2, and L: 3000 kg hm-2) and no straw incorporation was used as the control (CK). The levels of soil nutrients, soil organic carbon (SOC), soil labile organic carbon (LOC), and enzyme activities were analyzed each year after the wheat harvest. After straw incorporation for four years, the results showed that variable straw amounts had different effects on the soil fertility indices, where treatment H had the greatest effect. Compared with CK, the average soil available N, available P, available K, SOC, and LOC levels were higher in the 0–40 cm soil layers after straw incorporation treatments, i.e., 9.1–30.5%, 9.8–69.5%, 10.3–27.3%, 0.7–23.4%, and 44.4–49.4% higher, respectively. On average, the urease, phosphatase, and invertase levels in the 0–40 cm soil layers were 24.4–31.3%, 9.9–36.4%, and 42.9–65.3% higher, respectively. Higher yields coupled with higher nutrient contents were achieved with H, M and L compared with CK, where these treatments increased the crop yields by 26.75%, 21.51%, and 7.15%, respectively.

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In 2005, the WHO Western Pacific Region adopted the hepatitis B control goal of reducing the hepatitis B surface antigen seroprevalence in children at least 5 years of age to less than 2% by 2012. Universal infant immunization with three doses of hepatitis B vaccine, including a timely birth dose, is the key recommended strategy. Measuring seroprevalence in children at least 5 years of age takes into account the period when the risk of acquiring a chronic infection is highest and provides an indicator that can be monitored in the short term, within 5 years of vaccine introduction, and which correlates strongly with the long-term consequences of hepatitis B.A time-bound supranational hepatitis B control goal was chosen to create a sense of political urgency for strengthening routine immunization services and improving access to delivery care as well as providing resources for hepatitis B vaccination. Consequently, the programme strategies selected are not stand-alone but also contribute to strengthening health systems. Independent certification of achievement of the control goal, hitherto used mainly for eradication goals, is planned for all countries.Early assessment showed that adopting the regional goal led to greater political commitment, with reduced inequalities in hepatitis B vaccination between and within countries. Previous declining trends in routine immunization coverage also show signs of reversal and there is major progress in providing timely birth doses. A similar approach may be relevant to countries in Africa and South Asia, that have a high hepatitis B disease burden faltering routine immunization and poor access to skilled delivery care.Une traduction en français de ce résumé figure à la fin de l'article. Al final del artículo se facilita una traducción al español. ‫املقالة.‬ ‫لهذه‬ ‫الكامل‬ ‫النص‬ ‫نهاية‬ ‫يف‬ ‫الخالصة‬ ‫لهذه‬ ‫العربية‬ ‫الرتجمة‬ a Western

The emergence of "water-in-salt" carbon-based supercapacitors presents great potential for further improving the energy density, owing to the extended electrochemical stability window. However, not only low conductivity and high viscosity hinder the superior rate performance, but also the high cost of salts limits their commercialization. Here, we report a low-cost concentrated sodium nitrate electrolyte for high-performance and ultra-stable supercapacitors, based on good electrochemical stability, high conductivity, and low viscosity. In the wide operation voltage range of 0-2.1 V, the constructed symmetric supercapacitor based on commercial active carbon exhibits a high specific capacitance of 32.68 F g À 1 at 1 A g À 1 . Moreover, superior rate capability (83 % capacitance retention from 1 to 20 A g À 1 ) and excellent cycle stability (90 % capacitance retention after 9000 cycles) are also demonstrated. Consequently, this electrolyte system could be the most attractive candidate for promising carbon-based supercapacitors to further improve the energy density.[a] Prof.