A robust stratigraphic framework and a coherent depositional ramp model for the Zitai,Dawan,Meitan and Ningkuo formations of Floian–Darriwilian age(Early–Middle Ordovician)in the Yangtze(Daoba,Xiangshuidong,Daling,G...A robust stratigraphic framework and a coherent depositional ramp model for the Zitai,Dawan,Meitan and Ningkuo formations of Floian–Darriwilian age(Early–Middle Ordovician)in the Yangtze(Daoba,Xiangshuidong,Daling,Gudongkou and Honghuayuan sections)and Jiangnan regions(Nanba section)was created based on lithofacies and major element analysis.Three siliciclastic(LF1–3)and six carbonate(LF4–9)lithofacies are recognized representing sediments that were deposited in mixed siliciclastic and carbonate ramp environment.The intensity of mixed sedimentation and terrigenous input were evaluated using the elemental proxies Intensity of Mixed sedimentation(IM)and Aluminum Accumulation Rate(Al AR),as well as their mean values during certain time intervals.Mixed sediments are most well-developed along the marginal Yangtze region,strongly impacted by recurrent influx of westerly derived terrigenous materials in response to global eustatic changes and regional tectonic movements,shaping the gently southeast-dipping morphology.Regular terrigenous influx resulted in periods of enhanced primary productivity on the Yangtze Ramp as evidenced by matching biodiversity peaks in planktonic organisms,i.e.,chitinozoans and acritarchs.Brachiopods and other shelly fauna were also able to proliferate as new niches developed along the gently dipping ramp floor with substrate changes.The biodiversification patterns suggest that terrigenous influx controlled in part by regional tectonics played a more important role than previously thought in the development of Great Ordovician Biodiversification Event in South China.展开更多
目的探究抗阻训练对60岁以上老年人全身和下肢骨折高发部位(腰椎、髋关节、股骨大转子和股骨颈等)骨密度(BMD)的影响。方法计算机检索中国知网(CNKI)、PubMed、Elsevier、Web of Science(WOS)等数据库,全面收集有关抗阻训练对老年人BMD...目的探究抗阻训练对60岁以上老年人全身和下肢骨折高发部位(腰椎、髋关节、股骨大转子和股骨颈等)骨密度(BMD)的影响。方法计算机检索中国知网(CNKI)、PubMed、Elsevier、Web of Science(WOS)等数据库,全面收集有关抗阻训练对老年人BMD影响的随机对照试验研究(RCT);运用Cochrane偏倚风险评估工具对纳入文献进行方法学质量和发表偏倚性评价;采用ReMan5.3.5软件对所得数据进行统计学处理和敏感性检验。结果共纳入文献17篇,其中低偏倚风险6篇,中等偏倚风险9篇,偏倚风险较高2篇;纳入分析总样本量719人,平均年龄均大于60岁。meta分析结果显示,抗阻训练对老年人全身(SMD=0.21,I2=68%,P=0.38)和股骨大转子BMD(SMD=0.22,I2=56%,P=0.22)具有一定提高作用,但无显著性。抗阻训练可显著提高老年人腰椎(SMD=0.46,I2=70%,P=0.01)、髋关节(SMD=0.34,I2=16%,P=0.005)和股骨颈BMD(SMD=0.53,I2=60%,P=0.000 5)。结论抗阻训练对老年人BMD有一定提高作用;对老年人腰椎、髋关节和股骨颈BMD具有显著的提高作用。适当的抗阻训练可有效保护老年人骨骼,预防骨质疏松。展开更多
基金funded by National Natural Science Foundation of China(Grant Nos.42102130,41972011)Natural Science Foundation of Jiangsu Province(Grant No.BK20191101)+2 种基金Chinese Academy of Sciences(Grant No.XDB26000000)China Scholarship Council(Grant No.202004910207)State Key Laboratory of Palaeobiology and Stratigraphy。
文摘A robust stratigraphic framework and a coherent depositional ramp model for the Zitai,Dawan,Meitan and Ningkuo formations of Floian–Darriwilian age(Early–Middle Ordovician)in the Yangtze(Daoba,Xiangshuidong,Daling,Gudongkou and Honghuayuan sections)and Jiangnan regions(Nanba section)was created based on lithofacies and major element analysis.Three siliciclastic(LF1–3)and six carbonate(LF4–9)lithofacies are recognized representing sediments that were deposited in mixed siliciclastic and carbonate ramp environment.The intensity of mixed sedimentation and terrigenous input were evaluated using the elemental proxies Intensity of Mixed sedimentation(IM)and Aluminum Accumulation Rate(Al AR),as well as their mean values during certain time intervals.Mixed sediments are most well-developed along the marginal Yangtze region,strongly impacted by recurrent influx of westerly derived terrigenous materials in response to global eustatic changes and regional tectonic movements,shaping the gently southeast-dipping morphology.Regular terrigenous influx resulted in periods of enhanced primary productivity on the Yangtze Ramp as evidenced by matching biodiversity peaks in planktonic organisms,i.e.,chitinozoans and acritarchs.Brachiopods and other shelly fauna were also able to proliferate as new niches developed along the gently dipping ramp floor with substrate changes.The biodiversification patterns suggest that terrigenous influx controlled in part by regional tectonics played a more important role than previously thought in the development of Great Ordovician Biodiversification Event in South China.
文摘目的探究抗阻训练对60岁以上老年人全身和下肢骨折高发部位(腰椎、髋关节、股骨大转子和股骨颈等)骨密度(BMD)的影响。方法计算机检索中国知网(CNKI)、PubMed、Elsevier、Web of Science(WOS)等数据库,全面收集有关抗阻训练对老年人BMD影响的随机对照试验研究(RCT);运用Cochrane偏倚风险评估工具对纳入文献进行方法学质量和发表偏倚性评价;采用ReMan5.3.5软件对所得数据进行统计学处理和敏感性检验。结果共纳入文献17篇,其中低偏倚风险6篇,中等偏倚风险9篇,偏倚风险较高2篇;纳入分析总样本量719人,平均年龄均大于60岁。meta分析结果显示,抗阻训练对老年人全身(SMD=0.21,I2=68%,P=0.38)和股骨大转子BMD(SMD=0.22,I2=56%,P=0.22)具有一定提高作用,但无显著性。抗阻训练可显著提高老年人腰椎(SMD=0.46,I2=70%,P=0.01)、髋关节(SMD=0.34,I2=16%,P=0.005)和股骨颈BMD(SMD=0.53,I2=60%,P=0.000 5)。结论抗阻训练对老年人BMD有一定提高作用;对老年人腰椎、髋关节和股骨颈BMD具有显著的提高作用。适当的抗阻训练可有效保护老年人骨骼,预防骨质疏松。
