Census data of 2000 indicated that the Chinese population aged 65 and over had accounted for 7% of the total population. In urban areas, in particular, that ratio was 6.30% and in rural areas, it was 7.35%. On average...Census data of 2000 indicated that the Chinese population aged 65 and over had accounted for 7% of the total population. In urban areas, in particular, that ratio was 6.30% and in rural areas, it was 7.35%. On average, China had entered an aging society. In recent years, old-age support in rural China has caught the attention of government officials and scholars alike. This is because rural households have undergone drastic transformation in size and structure as a result of the enforcement of the family planning policy. Coupled with the urbanization process andmassive migration of rural laborers into cities, the aging process in rural China has accelerated,challenging the traditional pattern of old-age support in rural China.展开更多
Canopy temperature (CT), leaf water potential (LWP) and spikelet fertility (SF) of a set of RILs (F9) from the cross between Zhenshan97B and IRAT109 were investi- gated under two soil moisture regimes in a drought scr...Canopy temperature (CT), leaf water potential (LWP) and spikelet fertility (SF) of a set of RILs (F9) from the cross between Zhenshan97B and IRAT109 were investi- gated under two soil moisture regimes in a drought screen facility. In water stress condition, CT was negatively corre- lated with SF (r = ?0.2867) and LWP (r = ?0.2740), and LWP was positively associated with SF (r = 0.1696). These results indicated that the plant with high drought tolerant ability could maintain higher LWP and lower CT, leading to higher SF. A total of 44 main effect QTLs were associated with CT, LWP and SF. The accumulated contributionsof QTLs forCT, LWP and SF were 87.85%, 15.06%, 79.46% under well water condition and 72.61%, 87.68%, 33.29% under stress condi- tion, respectively. Totally 45 pairs of digenic interactions were detected. The accumulated contribution of digenic epistasis on CT, LWP and SF were 55.69%, 47.15%, 48.15% under well water condition and 53.44%, 57.94%, 54.62% under water stress condition. Compared with other drought tolerance QTL mapping researches in rice, 19 main effect QTLs were found to be located at the same or closely con- joint regions.展开更多
The main purpose of this paper is to study the asymptotic property of the fourth power mean of the general k-th Kloosterman sums, and give an interesting asymptotic formula.
文摘Census data of 2000 indicated that the Chinese population aged 65 and over had accounted for 7% of the total population. In urban areas, in particular, that ratio was 6.30% and in rural areas, it was 7.35%. On average, China had entered an aging society. In recent years, old-age support in rural China has caught the attention of government officials and scholars alike. This is because rural households have undergone drastic transformation in size and structure as a result of the enforcement of the family planning policy. Coupled with the urbanization process andmassive migration of rural laborers into cities, the aging process in rural China has accelerated,challenging the traditional pattern of old-age support in rural China.
基金This study was supported by the Hi-Technology Research and Development Program of China(Grant No.2003AA207010)the National Basic Research Program of China(Grant No.2004CB 117204)..
文摘Canopy temperature (CT), leaf water potential (LWP) and spikelet fertility (SF) of a set of RILs (F9) from the cross between Zhenshan97B and IRAT109 were investi- gated under two soil moisture regimes in a drought screen facility. In water stress condition, CT was negatively corre- lated with SF (r = ?0.2867) and LWP (r = ?0.2740), and LWP was positively associated with SF (r = 0.1696). These results indicated that the plant with high drought tolerant ability could maintain higher LWP and lower CT, leading to higher SF. A total of 44 main effect QTLs were associated with CT, LWP and SF. The accumulated contributionsof QTLs forCT, LWP and SF were 87.85%, 15.06%, 79.46% under well water condition and 72.61%, 87.68%, 33.29% under stress condi- tion, respectively. Totally 45 pairs of digenic interactions were detected. The accumulated contribution of digenic epistasis on CT, LWP and SF were 55.69%, 47.15%, 48.15% under well water condition and 53.44%, 57.94%, 54.62% under water stress condition. Compared with other drought tolerance QTL mapping researches in rice, 19 main effect QTLs were found to be located at the same or closely con- joint regions.
基金the National Natural Science Foundation of China (No.10271093) the Shanxi Provincial Natural Science Foundation of China.
文摘The main purpose of this paper is to study the asymptotic property of the fourth power mean of the general k-th Kloosterman sums, and give an interesting asymptotic formula.
