Background:The effect of hamstring flexibility on the peak hamstring muscle strains in sprinting,until now,remained unknown,which limited our understanding of risk factors of hamstring muscle strain injury(hamstring i...Background:The effect of hamstring flexibility on the peak hamstring muscle strains in sprinting,until now,remained unknown,which limited our understanding of risk factors of hamstring muscle strain injury(hamstring injury).As a continuation of our previous study,this study was aimed to examine the relationship between hamstring flexibility and peak hamstring muscle strains in sprinting.Methods:Ten male and 10 female college students participated in this study.Hamstring flexibility,isokinetic strength data,three-dimensional(3D)kinematic data in a hamstring isokinetic test,and kinematic data in a sprinting test were collected for each participant.The optimal hamstring muscle lengths and peak hamstring muscle strains in sprinting were determined for each participant.Results:The muscle strain of each of the 3 biarticulated hamstring muscles reached a peak during the late swing phase.Peak hamstring muscle strains were negatively correlated to hamstring flexibility(0.1179 ≤ R2≤ 0.4519,p = 0.001) but not to hip and knee joint positions at the time of peak hamstring muscle strains.Peak hamstring muscle strains were not different for different genders.Peak muscle strains of biceps long head(0.071 ± 0.059) and semitendinosus(0.070 ± 0.055) were significantly greater than that of semimembranosus(0.064 ± 0.054).Conclusion:A potential for hamstring injury exists during the late swing phase of sprinting.Peak hamstring muscle strains in sprinting are negatively correlated to hamstring flexibility across individuals.The magnitude of peak muscle strains is different among hamstring muscles in sprinting,which may explain the different injury rate among hamstring muscles.展开更多
Using the methods of the Gutenberg magnitude energy empirical formula and the Benioff seismic strain energy release curve,we make a systematic study on seismic strain energy release of historical earthquakes in the so...Using the methods of the Gutenberg magnitude energy empirical formula and the Benioff seismic strain energy release curve,we make a systematic study on seismic strain energy release of historical earthquakes in the southeastern margin of the Qinghai-Tibetan Plateau since 1500.This paper provides a periodic table of the earthquake strain energy release in the fault zones and the fault block areas.The study shows that seismic strain energy release is strong in the east and south,and weak in the west and north.The overall seismic strain energy release of the Yushu-Xianshuihe-Xiaojiang fault system is consistent with the quasi-periodic pattern.The seismic cycle of some fault zones and fault block areas shows synchronization to a certain extent.The risk cannot be ignored in the current large release period of seismic strain energy in the southeastern margin of the Qinghai-Tibetan plateau.Local seismic risk analysis shows that seismic risk is very high on the Anninghe-Zemuhe and Xiaojiang fault zones.These dangerous zones need follow-up research.In future,it is necessary to combine different research methods to improve the reliability of seismic risk assessment.展开更多
Since 2001, there have occurred in succession the 2001 Kunlun Mountains M S8. 1earthquake,the 2008 Wenchuan M S8. 0 earthquake,the 2010 Yushu M S7. 1 earthquake and the 2012 Lushan M S7. 0 earthquake in the periphery ...Since 2001, there have occurred in succession the 2001 Kunlun Mountains M S8. 1earthquake,the 2008 Wenchuan M S8. 0 earthquake,the 2010 Yushu M S7. 1 earthquake and the 2012 Lushan M S7. 0 earthquake in the periphery of the Bayan Har block. By comparison of the characteristics of seismic strain release variations before and after the Kunlun Mountains M S8. 1 earthquake in the same time length in the geodynamical related regions,we found that the seismic strain release was obviously enhanced after the earthquake in the Longmenshan area,Batang area,and the NS-trending valleys at the west of the Hot Spring Basin. The Wenchuan earthquake occurred in the first area,and the Yushu earthquake is related to the second area. After the earthquake rupture occurred on the East Kunlun fault zone on the northern boundary of the Bayan Har Block,crustal materials on the south side of the fault zone migrated to the southeast,leading to a concentration of tectonic deformation in the Longmenshan thrust belt, e ventually rupturing on the Longmenshan thrust belt. This earthquake case illustrates that seismicity enhancement zones are possibly prone to long-term destructive earthquakes. After the M S7. 3 earthquake in Yutian,Xinjiang on February 12,2014,earthquake frequency and seismic strain release markedly increased in the junction area between the eastern Qilian Mountain tectonic belt and the Altun Tagh fault zone,where more attention should be paid to the long-term seismic risk.展开更多
目的探究2013-2018年徐州市非结核分枝杆菌(non-tuberculous mycobacteria,NTM)感染分布和感染危险因素。方法选取2013年1月至2018年12月徐州地区各医疗机构所有疑似NTM病而转诊至徐州市传染病医院并被确诊的患者97例,作为感染组,分离出...目的探究2013-2018年徐州市非结核分枝杆菌(non-tuberculous mycobacteria,NTM)感染分布和感染危险因素。方法选取2013年1月至2018年12月徐州地区各医疗机构所有疑似NTM病而转诊至徐州市传染病医院并被确诊的患者97例,作为感染组,分离出NTM菌株97株,对标本进行抗酸染色,PCR-反向点杂交,行分枝杆菌培养,并进行菌群菌种鉴定。分析NTM感染患者的性别、治疗史和户籍类型分布。选取同时期诊断为结核分支杆菌感染者136例,作为对照组。对NTM感染者进行单因素分析和非条件logistic回归分析。结果确诊NTM感染97例,分离出7种分枝杆菌,感染率分别为胞内分枝杆菌40.2%、鸟分枝杆菌24.7%、堪萨斯分枝杆菌12.4%、龟分枝杆菌10.3%、脓肿分枝杆菌8.2%、浅黄分枝杆菌3.1%和戈登分枝杆菌1.0%。男性鸟分枝杆菌感染率(17.5%比7.2%)和堪萨斯分枝杆菌感染率(10.3%比2.1%)均显著高于女性,差异均有统计学意义(P<0.05)。近一年化疗患者胞内分枝杆菌和鸟分枝杆菌感染率均显著高于有抗菌药物史和长期服用免疫抑制剂的患者,差异均有统计学意义(P<0.05)。各分枝杆菌在城镇和农村户籍之间差异无统计学意义(P>0.05)。单因素分析和非条件logistic回归分析结果显示,农村户籍(OR=4.67,95%CI:2.66~8.20)、支气管扩张(OR=5.59,95%CI:3.19~12.33)、薄壁空洞(OR=4.16,95%CI:2.10~8.22)、吸烟史10~20年(OR=3.38,95%CI:1.76~6.47)、吸烟史>20年(OR=3.23,95%CI:1.68~6.19)、结核菌素纯蛋白衍生物(purified protein derivative,PPD)试验弱阳性(OR=6.56,95%CI:3.59~11.99)、化疗史(OR=7.52,95%CI:2.46~23.02)、抗菌药物史(OR=2.96,95%CI:1.70~5.13)、长期服用免疫抑制剂(OR=5.11,95%CI:2.35~11.15)、饮用生水(OR=1.99,95%CI:1.09~3.61)和接触禽类史(OR=4.31,95%CI:2.47~7.51)是NTM感染的危险因素(P<0.05)。结论NTM感染者中,男性和化疗患者更易感染胞内分枝杆菌和鸟分枝杆菌,且农村户籍、薄壁空洞、吸烟史(>10年)、PPD弱阳性、化疗史、抗菌药物史、长期服用免疫抑制剂、饮用生水和接触禽类史是NTM感染的危险因素。展开更多
基金supported by the National Natural Science Foundation of China(No.81572212)the Fundamental Research Funds for the Central Universities of China(No.2016BS013)
文摘Background:The effect of hamstring flexibility on the peak hamstring muscle strains in sprinting,until now,remained unknown,which limited our understanding of risk factors of hamstring muscle strain injury(hamstring injury).As a continuation of our previous study,this study was aimed to examine the relationship between hamstring flexibility and peak hamstring muscle strains in sprinting.Methods:Ten male and 10 female college students participated in this study.Hamstring flexibility,isokinetic strength data,three-dimensional(3D)kinematic data in a hamstring isokinetic test,and kinematic data in a sprinting test were collected for each participant.The optimal hamstring muscle lengths and peak hamstring muscle strains in sprinting were determined for each participant.Results:The muscle strain of each of the 3 biarticulated hamstring muscles reached a peak during the late swing phase.Peak hamstring muscle strains were negatively correlated to hamstring flexibility(0.1179 ≤ R2≤ 0.4519,p = 0.001) but not to hip and knee joint positions at the time of peak hamstring muscle strains.Peak hamstring muscle strains were not different for different genders.Peak muscle strains of biceps long head(0.071 ± 0.059) and semitendinosus(0.070 ± 0.055) were significantly greater than that of semimembranosus(0.064 ± 0.054).Conclusion:A potential for hamstring injury exists during the late swing phase of sprinting.Peak hamstring muscle strains in sprinting are negatively correlated to hamstring flexibility across individuals.The magnitude of peak muscle strains is different among hamstring muscles in sprinting,which may explain the different injury rate among hamstring muscles.
基金funded jointly by the China Geological Survey (Project Grant No. 1212011120163, 12120114002101)the National Natural Science Foundation of China (Project Grant No: 41171009)the basal research fund of Institute of Geomechanics,Chinese Academy of Geological Sciences (DXLXJK201410)
文摘Using the methods of the Gutenberg magnitude energy empirical formula and the Benioff seismic strain energy release curve,we make a systematic study on seismic strain energy release of historical earthquakes in the southeastern margin of the Qinghai-Tibetan Plateau since 1500.This paper provides a periodic table of the earthquake strain energy release in the fault zones and the fault block areas.The study shows that seismic strain energy release is strong in the east and south,and weak in the west and north.The overall seismic strain energy release of the Yushu-Xianshuihe-Xiaojiang fault system is consistent with the quasi-periodic pattern.The seismic cycle of some fault zones and fault block areas shows synchronization to a certain extent.The risk cannot be ignored in the current large release period of seismic strain energy in the southeastern margin of the Qinghai-Tibetan plateau.Local seismic risk analysis shows that seismic risk is very high on the Anninghe-Zemuhe and Xiaojiang fault zones.These dangerous zones need follow-up research.In future,it is necessary to combine different research methods to improve the reliability of seismic risk assessment.
基金jointly supported by National Science Foundation of China(41302171)Active Fault Exploration in China(60112304)Basic Scientific Research Funds of China Earthquake Administration(2014IES0401,2012IES010303)
文摘Since 2001, there have occurred in succession the 2001 Kunlun Mountains M S8. 1earthquake,the 2008 Wenchuan M S8. 0 earthquake,the 2010 Yushu M S7. 1 earthquake and the 2012 Lushan M S7. 0 earthquake in the periphery of the Bayan Har block. By comparison of the characteristics of seismic strain release variations before and after the Kunlun Mountains M S8. 1 earthquake in the same time length in the geodynamical related regions,we found that the seismic strain release was obviously enhanced after the earthquake in the Longmenshan area,Batang area,and the NS-trending valleys at the west of the Hot Spring Basin. The Wenchuan earthquake occurred in the first area,and the Yushu earthquake is related to the second area. After the earthquake rupture occurred on the East Kunlun fault zone on the northern boundary of the Bayan Har Block,crustal materials on the south side of the fault zone migrated to the southeast,leading to a concentration of tectonic deformation in the Longmenshan thrust belt, e ventually rupturing on the Longmenshan thrust belt. This earthquake case illustrates that seismicity enhancement zones are possibly prone to long-term destructive earthquakes. After the M S7. 3 earthquake in Yutian,Xinjiang on February 12,2014,earthquake frequency and seismic strain release markedly increased in the junction area between the eastern Qilian Mountain tectonic belt and the Altun Tagh fault zone,where more attention should be paid to the long-term seismic risk.
文摘目的探究2013-2018年徐州市非结核分枝杆菌(non-tuberculous mycobacteria,NTM)感染分布和感染危险因素。方法选取2013年1月至2018年12月徐州地区各医疗机构所有疑似NTM病而转诊至徐州市传染病医院并被确诊的患者97例,作为感染组,分离出NTM菌株97株,对标本进行抗酸染色,PCR-反向点杂交,行分枝杆菌培养,并进行菌群菌种鉴定。分析NTM感染患者的性别、治疗史和户籍类型分布。选取同时期诊断为结核分支杆菌感染者136例,作为对照组。对NTM感染者进行单因素分析和非条件logistic回归分析。结果确诊NTM感染97例,分离出7种分枝杆菌,感染率分别为胞内分枝杆菌40.2%、鸟分枝杆菌24.7%、堪萨斯分枝杆菌12.4%、龟分枝杆菌10.3%、脓肿分枝杆菌8.2%、浅黄分枝杆菌3.1%和戈登分枝杆菌1.0%。男性鸟分枝杆菌感染率(17.5%比7.2%)和堪萨斯分枝杆菌感染率(10.3%比2.1%)均显著高于女性,差异均有统计学意义(P<0.05)。近一年化疗患者胞内分枝杆菌和鸟分枝杆菌感染率均显著高于有抗菌药物史和长期服用免疫抑制剂的患者,差异均有统计学意义(P<0.05)。各分枝杆菌在城镇和农村户籍之间差异无统计学意义(P>0.05)。单因素分析和非条件logistic回归分析结果显示,农村户籍(OR=4.67,95%CI:2.66~8.20)、支气管扩张(OR=5.59,95%CI:3.19~12.33)、薄壁空洞(OR=4.16,95%CI:2.10~8.22)、吸烟史10~20年(OR=3.38,95%CI:1.76~6.47)、吸烟史>20年(OR=3.23,95%CI:1.68~6.19)、结核菌素纯蛋白衍生物(purified protein derivative,PPD)试验弱阳性(OR=6.56,95%CI:3.59~11.99)、化疗史(OR=7.52,95%CI:2.46~23.02)、抗菌药物史(OR=2.96,95%CI:1.70~5.13)、长期服用免疫抑制剂(OR=5.11,95%CI:2.35~11.15)、饮用生水(OR=1.99,95%CI:1.09~3.61)和接触禽类史(OR=4.31,95%CI:2.47~7.51)是NTM感染的危险因素(P<0.05)。结论NTM感染者中,男性和化疗患者更易感染胞内分枝杆菌和鸟分枝杆菌,且农村户籍、薄壁空洞、吸烟史(>10年)、PPD弱阳性、化疗史、抗菌药物史、长期服用免疫抑制剂、饮用生水和接触禽类史是NTM感染的危险因素。
