The Karakoram Highway(KKH),a part of the China–Pakistan Economic Corridor(CPEC),is a major highway connecting northern Pakistan to China.The inventorying and analysis of landslides along KKH are challenging because o...The Karakoram Highway(KKH),a part of the China–Pakistan Economic Corridor(CPEC),is a major highway connecting northern Pakistan to China.The inventorying and analysis of landslides along KKH are challenging because of poor accessibility,vast study area,limited availability of ground-based datasets,and the complexity of landslide processes in the region.In order to preserve life,property,and infrastructure,and to enable the uninterrupted and efficient operation of the KKH,it is essential to strengthen measures for the prevention and control of geological disasters.In the present study,SBASInSAR(Small Baseline Subsets-Interferometric Synthetic Aperture Radar)was used to process 150 scenes of Sentinel 1-A images in the year 2017 along the Karakoram Highway.A total of 762 landslides,including 57 complex landslides,126 rock falls,167 debris slides,and 412 unstable slopes,ranging in size between 0.0017 and 10.63 km2 were identified.Moreover,this study also gains an inventory of 40 active glacier movements in this region.Landslide categorization,displacements characteristics,spatial distribution,and their relationship with various contributing factors have been successfully investigated along the entire KKH using image interpretation and frequency-area statistics.The criteria adopted for landslides categorization is presented in the study.The results showed that the 2-D ground deformation derived in Hunza valley echoes well with the general regional landslides characteristics.The spatial distribution analysis revealed that there are clumped distributions of landslides in the Gaizi,Tashkurgan,and Khunjerab in China,as well as in Hunza valley,and north of Chilas city in Pakistan.Statistical results indicated that these landslides mainly occur on south-facing slopes with a slope angle of 20°–45°and elevation relief of 550–2,100 m.Landslide development is also related to low vegetation cover and weathering effects in mountain gullies.Overall,our study provides scientific data support and theoretical references for prevention,control,and mitigation of geological disasters in the Karakoram region.展开更多
目的分析白细胞介素23(IL-23)、腺苷脱氨酶(ADA)、白三烯B4(LTB4)在结核性脑膜炎患者脑脊液中的表达水平及临床意义。方法选取2015年1月—2017年12月我院收治的脑膜炎患者206例,根据疾病类型将206例分为结核性脑膜炎组79例、化脓性脑膜...目的分析白细胞介素23(IL-23)、腺苷脱氨酶(ADA)、白三烯B4(LTB4)在结核性脑膜炎患者脑脊液中的表达水平及临床意义。方法选取2015年1月—2017年12月我院收治的脑膜炎患者206例,根据疾病类型将206例分为结核性脑膜炎组79例、化脓性脑膜炎组61例和病毒性脑膜炎组66例。比较3组脑脊液IL-23、ADA、LTB4水平;根据英国医学研究理事会(UK medical research council,MRC)分期标准,比较不同病情分期的结核性脑膜炎患者脑脊液IL-23、ADA、LTB4表达情况;采用Spearman相关性分析,探讨MRC分期与结核性脑膜炎患者脑脊液IL-23、ADA、LTB4表达水平的相关性。结果①3组脑脊液IL-23、ADA、LTB4水平存在明显差异(P<0.01);结核性脑膜炎组脑脊液IL-23、ADA、LTB4水平显著高于化脓性脑膜炎组及病毒性脑膜炎组,化脓性脑膜炎组上述指标亦高于病毒性脑膜炎组,差异均有统计学意义(P<0.01)。②不同MRC分期的结核性脑膜炎患者脑脊液IL-23、ADA、LTB4表达水平存在明显差异(P<0.01),Ⅲ期患者IL-23、ADA、LTB4均高于Ⅰ期患者,且Ⅲ期患者中仅有LTB4高于Ⅱ期患者,差异均有统计学意义(P<0.01)。③结核性脑膜炎患者脑脊液IL-23、ADA、LTB4表达水平与MRC分期呈正相关(r分别为0.361、0.320、0.299,P均<0.001)。结论结核性脑膜炎患者脑脊液IL-23、ADA、LTB4表达水平随病情严重程度的加重而升高,对临床初步评估患者病情严重程度及预后有一定意义。展开更多
Numerous large-scale fragmented bedrock landslides developed along major fault system is a world-wide phenomenon,which are often characterized with repeated reactivation throughout histories.Due to the large-scale and...Numerous large-scale fragmented bedrock landslides developed along major fault system is a world-wide phenomenon,which are often characterized with repeated reactivation throughout histories.Due to the large-scale and deep-seated features,it is normally difficult to control such landslides,which in turn pose great threat to local residents and infrastructures.Therefore,monitoring and forecasting these gigantic landslides has become a key protocol for risk reduction.This paper introduces such a typical massive landslide,named Yahuokou landslide,besides Min River in Zhouqu County,Gansu Province,China.Reactivated on July 16,2019 with a volume of approximately 4×106 m3,moving slowly and transitionally starting from top part,its toe had partially blocked the Min River and destroyed roads and houses eventually by August 11,2019.As to emergency response for such huge slowmoving landslide,there is no standard national protocols.Therefore,how to make effective emergency decision has become a challenge.Based on previous experiences,integrated multi-methods,including UAV imagery interpretation,we applied GNSS monitoring and field investigations in the early stages of landsliding,in order to assist the decisionmaking.The results show that the movement path of the current displacement is consistent with that of the 1989 reactivation event,and the slide body was separated into three relatively independent blocks with different sliding velocities and responses to rainfall.The upper and lower blocks appeared less affected by rainfall,while the middle block responded more to the changes in precipitations.It proves that the combined approaches using a variety of monitoring techniques can play an effective role in the monitoring of rapidly deformed transitional largescale landslides,and can also provide a set of reference methods for the emergency disposal of similar landslide hazards.展开更多
基金supported by National Key Research and Development Program of China(Grant No.2017YFC1501005)National Natural Science Foundation of China(Grant Nos.41661144046,42007232)+3 种基金the Science and Technology Major Project of Gansu Province(Grant No.19ZD2FA002)the Science and Technology Planning Project of Gansu Province(Grant No.18YF1WA114)the Fundamental Research Funds for the Central Universities(Grant Nos.lzujbky-2021-ey05)Second Tibetan Plateau Scientific Expedition and Research Program(Grant No.2019QZKK0902)。
文摘The Karakoram Highway(KKH),a part of the China–Pakistan Economic Corridor(CPEC),is a major highway connecting northern Pakistan to China.The inventorying and analysis of landslides along KKH are challenging because of poor accessibility,vast study area,limited availability of ground-based datasets,and the complexity of landslide processes in the region.In order to preserve life,property,and infrastructure,and to enable the uninterrupted and efficient operation of the KKH,it is essential to strengthen measures for the prevention and control of geological disasters.In the present study,SBASInSAR(Small Baseline Subsets-Interferometric Synthetic Aperture Radar)was used to process 150 scenes of Sentinel 1-A images in the year 2017 along the Karakoram Highway.A total of 762 landslides,including 57 complex landslides,126 rock falls,167 debris slides,and 412 unstable slopes,ranging in size between 0.0017 and 10.63 km2 were identified.Moreover,this study also gains an inventory of 40 active glacier movements in this region.Landslide categorization,displacements characteristics,spatial distribution,and their relationship with various contributing factors have been successfully investigated along the entire KKH using image interpretation and frequency-area statistics.The criteria adopted for landslides categorization is presented in the study.The results showed that the 2-D ground deformation derived in Hunza valley echoes well with the general regional landslides characteristics.The spatial distribution analysis revealed that there are clumped distributions of landslides in the Gaizi,Tashkurgan,and Khunjerab in China,as well as in Hunza valley,and north of Chilas city in Pakistan.Statistical results indicated that these landslides mainly occur on south-facing slopes with a slope angle of 20°–45°and elevation relief of 550–2,100 m.Landslide development is also related to low vegetation cover and weathering effects in mountain gullies.Overall,our study provides scientific data support and theoretical references for prevention,control,and mitigation of geological disasters in the Karakoram region.
文摘目的分析白细胞介素23(IL-23)、腺苷脱氨酶(ADA)、白三烯B4(LTB4)在结核性脑膜炎患者脑脊液中的表达水平及临床意义。方法选取2015年1月—2017年12月我院收治的脑膜炎患者206例,根据疾病类型将206例分为结核性脑膜炎组79例、化脓性脑膜炎组61例和病毒性脑膜炎组66例。比较3组脑脊液IL-23、ADA、LTB4水平;根据英国医学研究理事会(UK medical research council,MRC)分期标准,比较不同病情分期的结核性脑膜炎患者脑脊液IL-23、ADA、LTB4表达情况;采用Spearman相关性分析,探讨MRC分期与结核性脑膜炎患者脑脊液IL-23、ADA、LTB4表达水平的相关性。结果①3组脑脊液IL-23、ADA、LTB4水平存在明显差异(P<0.01);结核性脑膜炎组脑脊液IL-23、ADA、LTB4水平显著高于化脓性脑膜炎组及病毒性脑膜炎组,化脓性脑膜炎组上述指标亦高于病毒性脑膜炎组,差异均有统计学意义(P<0.01)。②不同MRC分期的结核性脑膜炎患者脑脊液IL-23、ADA、LTB4表达水平存在明显差异(P<0.01),Ⅲ期患者IL-23、ADA、LTB4均高于Ⅰ期患者,且Ⅲ期患者中仅有LTB4高于Ⅱ期患者,差异均有统计学意义(P<0.01)。③结核性脑膜炎患者脑脊液IL-23、ADA、LTB4表达水平与MRC分期呈正相关(r分别为0.361、0.320、0.299,P均<0.001)。结论结核性脑膜炎患者脑脊液IL-23、ADA、LTB4表达水平随病情严重程度的加重而升高,对临床初步评估患者病情严重程度及预后有一定意义。
基金funded by National Key Research and Development Program of China(Grant No.2017YFC1501005)the National Key R&D Program of China(Grant No.2018YFC1504704)+3 种基金the National Natural Science Foundation of China(Grant No.42007232)the Key Research and Development Program of Gansu Province(Grant No.20YF8FA074)the Science and Technology Major Project of Gansu Province(Grant No.19ZD2FA002)the Construction Project of Gansu Technological Innovation Center(Grant No.18JR2JA006)。
文摘Numerous large-scale fragmented bedrock landslides developed along major fault system is a world-wide phenomenon,which are often characterized with repeated reactivation throughout histories.Due to the large-scale and deep-seated features,it is normally difficult to control such landslides,which in turn pose great threat to local residents and infrastructures.Therefore,monitoring and forecasting these gigantic landslides has become a key protocol for risk reduction.This paper introduces such a typical massive landslide,named Yahuokou landslide,besides Min River in Zhouqu County,Gansu Province,China.Reactivated on July 16,2019 with a volume of approximately 4×106 m3,moving slowly and transitionally starting from top part,its toe had partially blocked the Min River and destroyed roads and houses eventually by August 11,2019.As to emergency response for such huge slowmoving landslide,there is no standard national protocols.Therefore,how to make effective emergency decision has become a challenge.Based on previous experiences,integrated multi-methods,including UAV imagery interpretation,we applied GNSS monitoring and field investigations in the early stages of landsliding,in order to assist the decisionmaking.The results show that the movement path of the current displacement is consistent with that of the 1989 reactivation event,and the slide body was separated into three relatively independent blocks with different sliding velocities and responses to rainfall.The upper and lower blocks appeared less affected by rainfall,while the middle block responded more to the changes in precipitations.It proves that the combined approaches using a variety of monitoring techniques can play an effective role in the monitoring of rapidly deformed transitional largescale landslides,and can also provide a set of reference methods for the emergency disposal of similar landslide hazards.