Grain production of rice (Oryza sativa L.) is a top priority in ensuring food security for human beings. One of the approaches to increase yield is to delay leaf senescence and to extend the available time for photosynthesis. MicroRNAs (miRNAs) are key regulators of aging and cellular senescence in eukaryotes. Here, to help understand their biological role in rice leaf senescence, we report identification of miRNAs and their putative target genes by deep sequencing of six small RNA libraries, six RNA-seq libraries and two degradome libraries from the leaves of two super hybrid rice, Nei-2-You 6 (N2Y6, age-resistant rice) and Liang-You-Pei 9 (LYP9, age-sensitive rice). In total 372 known miRNAs, 162 miRNA candidates and 1145 targets were identified. Compared with the expression of miRNAs in the leaves of LYP9, the numbers of miRNAs up-regulated and down-regulated in the leaves of N2Y6 were 47 and 30 at early stage of grain-filling, 21 and 17 at the middle stage, and 11 and 37 at the late stage, respectively. Six miRNA families, osa-miR159, osa-miR160 osa-miR164, osa-miR167, osa-miR172 and osa-miR1848, targeting the genes encoding APETALA2 (AP2), zinc finger proteins, salicylic acid-induced protein 19 (SIP19), auxin response factors (ARF) and NAC transcription factors, respectively, were found to be involved in leaf senescence through phytohormone signaling pathways. These results provided valuable information for understanding the miRNA-mediated leaf senescence of rice, and offered an important foundation for rice breeding.

Keywords: Employment; Entrepreneurship; college studentThe problem, employment difficulty, has become a heated issue again in recent years which attracted social attention. Statistics show that continuously increasing graduates Chinese colleges, 7.49 million in 2015, 7.7 million in 2016, will reach a record of the number of graduates. As for regions, for example, the number of graduates in Hebei province was 351000 in 2015, decreased by 15000 compared with last years, but the overall trend has been increasing by years. A problem both government and colleges facing now is that how to let such a large number of graduates be employed successfully. Colleges, a subject of higher education and a cradle of cultivating talents, bear unshakable responsibility in fostering employment of the graduates, each colleges and universities should take various measures positively to improve the employment of its' graduates. Local economic development and local college education is an interactive relation, and it is the employment and entrepreneurship of College Students that kinks the two subjects. With the fast amalgamation and development of Jing-Jin-Ji area, local colleges in hebei province, as a basement of cultivating talents, gradually exposed some prominent problems in how to help and foster the employment and entrepreneurship of College Students.

Coordinated Development for the Beijing-Tianjin-Hebei Region is a major strategy for economic and social development in the new century. Talents cooperation is the basic guarantee for the strategy implementation. Through literature research and field investigation, this paper analyses the necessity of talents cooperation in the coordinated development process on the historical basis of Beijing-Tianjin-Hebei Region and talentscooperation, Moreover, four paths are to be studied to promote its advancement, namely: talents-education, talents-selection, talents-adoption and talents-retention.