Zebrafish miR-214 modulates Hedgehog signaling to specify muscle cell fate

Numerous microRNAs (miRNAs) have been discovered in the genomes of higher eukaryotes, and functional studies indicate that they are important during development. However, little is known concerning the function of individual miRNAs. We approached this problem in zebrafish by combining identification of miRNA expression, functional analyses and experimental validation of potential targets. We show that miR-214 is expressed during early segmentation stages in somites and that varying its expression alters the expression of genes regulated by Hedgehog signaling. Inhibition of miR-214 results in a reduction or loss of slow-muscle cell types. We show that su(fu) mRNA, encoding a negative regulator of Hedgehog signaling, is targeted by miR-214. Through regulation of su(fu), miR-214 enables precise specification of muscle cell types by sharpening cellular responses to Hedgehog.     

我国廉租房建设中存在的问题及对策分析

廉租房作为解决城镇低收入家庭住房问题的一种主要渠道,其建设的进展情况并不乐观,在建设模式、资金供应、分配标准等方面仍存在不少问题。为此,需要加强认识、采取多元化融资方式、完善廉租房相关制度,使廉租房建设真正落实到位,从而促进我国住房保障体系乃至整个房地产市场的健康发展。     

An Empirical Study of Effects of Chinese Government＇s Tax Revenue and Expenditure on Its GDP＇s Growth

Public spending is a major policy tool for the government to adjust the macro economic progress. This paper characterizes the effects of shocks in government spending and taxes on Chinese economy growth since 1978. It does so by using a mixed structural VAR （SVAR） approach. Identification is achieved by using institutional information about the tax and spending to identify automatic and discretionary response, and by implication, to infer fiscal shocks. The results show positive government spending shocks as having a positive effect on output, and positive tax shocks as having a negative effects.     

关于新时期实验物理教学的几点思考

本文结合我校实际，对新时期实验物理教学中出现的一些问题和现象作了分析讨论。提出相应的措施和方法。