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By using the symbolic system of music, art, action and so on, the language symbol system of infants and young children in the prelinguistic stage can be activated, so that infants and young children can read picture books while learning oral language. This saves a lot of time for the learning and development of early writing language and provides the opportunity for infants and young children to integrate and apply oral language and early written language. The systematic training method include: the relationship between instruction and action, the cooperation between recognition pictures and language, the combination of literacy and meaning, and the guidance of reading and sentence breaking.

To investigate the effect of 27nt-miRNA on the differentiation of mesenchymal stem cells into vascular smooth muscle cells. The highly expression plasmids of 27nt-miRNA and anti-27nt-miRNA, and negative control plasmids were constructed, packaged with lentivirus and transfected into human umbilical cord mesenchymal stem cells (hUCMSCs). Collagen IV was added to induce hUCMSCs differentiation into blood vessel smooth muscle cells (VSMCs). The cell viability was measured by MTT assay. The expression of SMA, SM22α at mRNA and protein levels was determined by RT-PCR, immunocytochemical staining and Western blotting. Compared with the negative control group, the viability of the 27nt-miRNA overexpression group was decreased by 20.48% (P0.05), and the expression of SMA mRNA and SM22α mRNA and protein was significantly increased (P0.05); the viability of Anti-27nt-miRNA group was increased 18.07% (P0.05), and the expression of SMA mRNA and SM22α mRNA and protein was decreased (P0.05). In summary, 27nt-miRNA promotes mesenchymal stem cells differentiation into vascular smooth muscle cells and inhibits cells viability.为探讨27nt-miRNA 对间充质干细胞向血管平滑肌细胞分化影响，构建27nt-miRNA 过表达、反义序列Anti-27nt-miRNA 以及阴性对照的表达质粒，慢病毒包装后分别转染人脐带间充质干细胞 (hUCMSC)，加入Ⅳ型胶原诱导hUCMSC 定向分化为血管平滑肌细胞。四唑盐 (MTT) 比色法检测分化后细胞活力，免疫细胞化学染色法检测分化后细胞SM22α (兔抗平滑肌22α，smooth muscle 22α) 的表达，Western 印迹法和RT-PCR 检测分化后细胞内的SMA (兔抗平滑肌肌动蛋白，smooth muscle actin) mRNA、SM 22α mRNA 及其蛋白质表达情况。经检测，27nt-miRNA 过表达分化组与阴性对照组相比，细胞活力下降20.48% (P0.05)，SMA mRNA、SM22α mRNA及其蛋白质表达量明显升高 (P0.05)；而Anti-27nt-miRNA 分化组细胞活力上升了18.07% (P0.05)，SMA mRNA、SM22α mRNA 及其蛋白质表达量下降 (P0.05)。综上所述，27nt-miRNA 能够促进间充质干细胞向血管平滑肌细胞分化，并且抑制分化后的细胞活力。.

This study was conducted to investigate the effect of weaning age on growth performance, nutrient digestion and metabolism, and serological indicators, and to obtain an optimal weaning age in Hu lambs. Forty-eight newborn Hu lambs (birth weight, 2.53 ± 0.14 kg) were randomly divided into 4 groups. The lambs in control group (ER) suckled their dams. The lambs in other three experimental groups were weaned on milk replacer at 10, 20, and 30 days of age (EW10, EW20, and EW30 groups), respectively. The results were as follows: 1) lambs in EW10 and EW30 groups had a lower (P 0.05) among groups; however, the apparent digestibility and deposition of calcium in early weaned lambs were lower (P

Wireless bandwidth is a limited and scarce shared resource in MANETs. In our work, we are interested in the "end-to-end capacity" of the network, which we define to be the sum of the throughputs for each flow. This represents the service a network provides to its users. In this paper, we propose a routing protocol, called TB for traffic balancing, which increases the end-to-end capacity by more aggressively routing data through underutilized areas of a MANET. Simulation results show that TB performs better than other load-balancing protocols proposed in the literature. We also compare the experimental performance against lower bounds of maximum end-to-end capacity, discuss reasons for the performance gap, and identify possible future improvements to the protocol.

Several access points may be put into wireless ad hoc networks for people connecting to WWW or other Internet services. This kind of wireless network is called wireless mesh networks (WMNs) that still needs users to relay packets for other users. The meshed topology provides good reliability, market coverage, and scalability, as well as low upfront investment. However, due to the nature of routing algorithm the traffic load for a access point may be extremely heavy during particular periods while the other access points are in very light load. Consequently, the overall performance of the network are poor even the total traffic load is far below the system capacity. Traffic balancing proposed for wireless ad hoc networks provides an efficient solution to this problem. With right placement of the access points, the performance can be improved dramatically by traffic balancing.

The connection-oriented data service has been previously introduced in the IEEE 802.6 standard to support variable bit rate applications for which a certain guarantee on quality of service is required. So far, the proper tuning of the parameters of this service remains an open issue. In this work, we undertake the study of this service with the main objective of defining the needed mechanisms to properly set-up the parameters of the connection oriented service according to various quality of service requirements.