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72.
语篇关系作为衔接机制对语篇结构的完整性与连贯性起重要作用,以语料库语言学方法,收集大学英语四六级作文素材组成小型封闭生语料库,然后利用RST工具标注作文语篇结构组建RST语篇树库,基于树库的数据驱动学习提出中国英语学习者偏好使用的语篇关系集合及相关触发语的选用特征,结论是语篇关系的正误使用与作文分数等级呈正负相关的线性关系。 相似文献
73.
By using 162 third-year science students from the Independent College in Shandong University of Science and Tech nology,this paper investigated the relationship between their metacognitive ability and their CET4 score.The results indicated that their metacognitive ability,and the three subcategories have positive significant correlations with the students’CET4 score. 相似文献
74.
Yuan-yuan YAO Man-hua ZHU Feng-jiang ZHANG Chuan-yun WEN Lei-lei MA Wen-na WANG Can-can WANG Xian-bao LIU Li-na YU Ling-bo QIAN Jian-an WANG Min YAN 《Journal of Zhejiang University. Science. B》2013,14(6):511-517
It had been proved that administration of sevoflurane for the first two minutes of reperfusion effectively protects the heart against reperfusion injury in rats in vivo.Our aim was to investigate the duration of effective sevoflurane administration and its underlying mechanism in isolated rat hearts exposed to global ischemia/reperfusion(I/R) injury.Adult male Sprague-Dawley rats were randomly divided into six groups(n=12):a sham-operation group,an I/R group,and four sevoflurane postconditioning groups(S2,S5,S10,and S15).In the S2,S5,S10,and S15 groups,the duration times of sevoflurane administration were 2,5,10,and 15 min after the onset of reperfusion,respectively.The isolated rat hearts were mounted on the Langendorff system,and after a period of equilibrium were subjected to 40 min global ischemia and 120 min reperfusion.Left ventricular(LV) hemodynamic parameters were monitored throughout each experiment and the data at 30 min of equilibrium and 30,60,90,and 120 min of reperfusion were analyzed.Myocardial infarct size at the end of reperfusion(n=7 in each group) and the expression of myocardial phosphorylated Akt(p-Akt) after 15-min reperfusion were determined in a duplicate set of six groups of rat hearts(n=5 in each group).Compared with the I/R group,the S5,S10,and S15 groups had significantly improved left ventricular end-diastolic pressure(LVEDP),left ventricular developed pressure(LVDP),and the maximal rate of rise or fall of the LV pressure(±dP/dtmax),and decreased myocardial infarct size(P<0.05),but not the S2 group.After 15 min of reperfusion,the expression of p-Akt was markedly up-regulated in the S5,S10,and S15 groups compared with that in the I/R group(P<0.05),but not in the S2 group.Sevoflurane postconditioning for 5 min was sufficient to activate Akt and exert maximal cardioprotection against I/R injury in isolated rat hearts. 相似文献
75.
陈Min 《柳州职业技术学院学报》2001,1(2):64-69
本记载了广西鲤科鱼类三个亚科的鱼类34种(3种为新记录),其中Dan亚科5种、雅罗鱼亚科7种、Bai亚科22种。对与《广西水鱼志》记载有出入的物种作了说明;对某些物种的资源状况作了分析。 相似文献
76.
本文推导出利用外推法求算电池标准电动势E^o的一般公式,并论证了E+vRT/nFln「(v+^v+v-^v-)」1/vm/m^n与√m的直线关系。 相似文献
77.
78.
SA Peng-fei ZHAO Min FANG Shu-hua 《重庆大学学报(英文版)》2006,5(1):19-23
1 Introduction [1-3]The permanent magnetic actuator (PMA) technology first showed up in 1990s. It adopts a new working theory and a novel structure. With the combination of electrical magnetism and permanent magnetism, it can realize all functions of a br… 相似文献
79.
陈Min 《柳州职业技术学院学报》2001,1(3):56-60
本记载了广西鲤科鱼类三个亚科的鱼类35种和亚种(5种为新记录),其中鲴亚科6种、鲢亚科2种、鲍亚科27种和亚种。对与《广西淡水鱼类志》记载有出入的物种作了说明;对某些物种的资源状况作了分析。 相似文献
80.
TAO Min 《浙江大学学报(A卷英文版)》2007,8(6):969-977
Proximal point algorithms (PPA) are attractive methods for solving monotone variational inequalities (MVI). Since solving the sub-problem exactly in each iteration is costly or sometimes impossible, various approximate versions of PPA (APPA) are developed for practical applications. In this paper, we compare two APPA methods, both of which can be viewed as predic- tion-correction methods. The only difference is that they use different search directions in the correction-step. By extending the general forward-backward splitting methods, we obtain Algorithm I; in the same way, Algorithm II is proposed by spreading the general extra-gradient methods. Our analysis explains theoretically why Algorithm II usually outperforms Algorithm I. For computation practice, we consider a class of MVI with a special structure, and choose the extending Algorithm II to implement, which is inspired by the idea of Gauss-Seidel iteration method making full use of information about the latest iteration. And in particular, self-adaptive techniques are adopted to adjust relevant parameters for faster convergence. Finally, some nu- merical experiments are reported on the separated MVI. Numerical results showed that the extending Algorithm II is feasible and easy to implement with relatively low computation load. 相似文献