There are both pedagogical and theoretical grounds for asking second language writers to plan before they start writing.The question then arises whether pre-task planning(PTP)improves written output.To address this qu...There are both pedagogical and theoretical grounds for asking second language writers to plan before they start writing.The question then arises whether pre-task planning(PTP)improves written output.To address this question,this article reviewed 32 studies by comparing the effect of PTP either with no planning or with unpressured online planning(OLP).These studies also investigated the moderating effect of variables relating to the writer participants,the nature of the planning,and the writing tasks.The main findings are:(1)There is no clear evidence that PTP leads to better overall writing quality when this is measured using rating rubrics,(2)PTP generally results in more fluent writing,(3)its impact on syntactical and lexical complexity is inconsistent and negligible,(4)OLP does sometimes result in increased linguistic accuracy,and(5)there is insufficient evidence to reach clear conclusions about the role that moderating variables have on the impact of PTP,but the results suggest that collaborative(as opposed to individual planning)can lead to increased accuracy and that PTP tends to lead to more complex language when the writing task is a complex one.The article concludes with a set of principles to ensure better quality research and three general proposals for the kind of future research needed.展开更多
To investigate the bilateral shear strength of rectangular frame column subjected to oblique horizontal load, we presented a simplified space truss-arch model developed from unilateral truss-arch model. Main parameter...To investigate the bilateral shear strength of rectangular frame column subjected to oblique horizontal load, we presented a simplified space truss-arch model developed from unilateral truss-arch model. Main parameters in the new model were the cross-sectional area, transverse reinforcement raito, axial load, and material strength of the column. The reduction coefficient of concrete sterength owing to the severe cracking of column was also introduced in the model. Finally, 14 specimens under oblique horizontal load were tested to verified the feasibility and applicability of the space truss-arch model.展开更多
Objective:To determine the association between tea consumption and the risk of stroke. Methods:We searched the PubMed database from January 1966 to March 2012 and reviewed reference lists of retrieved articles to iden...Objective:To determine the association between tea consumption and the risk of stroke. Methods:We searched the PubMed database from January 1966 to March 2012 and reviewed reference lists of retrieved articles to identify relevant studies. Studies were included if they reported relative risks (RRs) and corresponding 95% confidence intervals (CIs) of stroke with respect to three or more categories of tea consumption. A random-effects model was used to combine the study-specific risk estimates. Results:Fourteen studies, consisting of 513 804 participants with a median follow-up of 11.5 years, were included in this meta-analysis. We observed a modest but statistically significant inverse association between tea consumption and risk of stroke. An increase of three cups/d in tea consumption was associated with a 13% decreased risk of stroke (RR 0.87; 95% CI, 0.81-0.94). The decreased risk of stroke with tea consumption was consistent among most subgroups. Based on the three studies that provided results for stroke subtypes, tea consumption was also inversely associated with the risk of ischemic stroke (RR 0.76; 95% CI, 0.69-0.84), but not cerebral hemorrhage (RR 0.96; 95% CI, 0.82-1.11) or subarachnoid hemorrhage (RR 0.81; 95% CI, 0.57-1.16). Conclusions:Tea consumption is associated with a decreased risk of stroke, particularly ischemic stroke. More well-designed, rigorously conducted studies are needed in order to make confident conclusions about the association between tea consumption and stroke subtypes.展开更多
文摘There are both pedagogical and theoretical grounds for asking second language writers to plan before they start writing.The question then arises whether pre-task planning(PTP)improves written output.To address this question,this article reviewed 32 studies by comparing the effect of PTP either with no planning or with unpressured online planning(OLP).These studies also investigated the moderating effect of variables relating to the writer participants,the nature of the planning,and the writing tasks.The main findings are:(1)There is no clear evidence that PTP leads to better overall writing quality when this is measured using rating rubrics,(2)PTP generally results in more fluent writing,(3)its impact on syntactical and lexical complexity is inconsistent and negligible,(4)OLP does sometimes result in increased linguistic accuracy,and(5)there is insufficient evidence to reach clear conclusions about the role that moderating variables have on the impact of PTP,but the results suggest that collaborative(as opposed to individual planning)can lead to increased accuracy and that PTP tends to lead to more complex language when the writing task is a complex one.The article concludes with a set of principles to ensure better quality research and three general proposals for the kind of future research needed.
基金Funded by Natural Science Foundation of Henan Province Office of Education (No. 2009A560007)Doctor Foundation of Henan Polytechnic University (No. B2008-7)
文摘To investigate the bilateral shear strength of rectangular frame column subjected to oblique horizontal load, we presented a simplified space truss-arch model developed from unilateral truss-arch model. Main parameters in the new model were the cross-sectional area, transverse reinforcement raito, axial load, and material strength of the column. The reduction coefficient of concrete sterength owing to the severe cracking of column was also introduced in the model. Finally, 14 specimens under oblique horizontal load were tested to verified the feasibility and applicability of the space truss-arch model.
基金Project (No. 2007C13058) supported by the Science and Technology Key Project of Zhejiang Province, China
文摘Objective:To determine the association between tea consumption and the risk of stroke. Methods:We searched the PubMed database from January 1966 to March 2012 and reviewed reference lists of retrieved articles to identify relevant studies. Studies were included if they reported relative risks (RRs) and corresponding 95% confidence intervals (CIs) of stroke with respect to three or more categories of tea consumption. A random-effects model was used to combine the study-specific risk estimates. Results:Fourteen studies, consisting of 513 804 participants with a median follow-up of 11.5 years, were included in this meta-analysis. We observed a modest but statistically significant inverse association between tea consumption and risk of stroke. An increase of three cups/d in tea consumption was associated with a 13% decreased risk of stroke (RR 0.87; 95% CI, 0.81-0.94). The decreased risk of stroke with tea consumption was consistent among most subgroups. Based on the three studies that provided results for stroke subtypes, tea consumption was also inversely associated with the risk of ischemic stroke (RR 0.76; 95% CI, 0.69-0.84), but not cerebral hemorrhage (RR 0.96; 95% CI, 0.82-1.11) or subarachnoid hemorrhage (RR 0.81; 95% CI, 0.57-1.16). Conclusions:Tea consumption is associated with a decreased risk of stroke, particularly ischemic stroke. More well-designed, rigorously conducted studies are needed in order to make confident conclusions about the association between tea consumption and stroke subtypes.