Cinnamomum camphora(L.)J.Presl.(Laurales:Lauraceae)is widely cultivated as an important landscape tree species in many urban areas in South China,especially in Shanghai City.Pagiophloeus tsushimanus Morimoto has becom...Cinnamomum camphora(L.)J.Presl.(Laurales:Lauraceae)is widely cultivated as an important landscape tree species in many urban areas in South China,especially in Shanghai City.Pagiophloeus tsushimanus Morimoto has become a destructive insect pest of C.camphora plantations in Shanghai,but the biological and ecological traits of this pest remain largely unknown.In this study,we investigated the damage and life history and determined the larval instar of P.tsushimanus.The results indicated that P.tsushimanus is a monophagous weevil pest,and C.camphora is the unique host tree species.C.camphora plantations in all administrative districts of Shanghai have been seriously damaged by P.tsushimanus.Adults often aggregate for feeding on the tender bark of twigs and occasionally on newly emerged buds.After experiencing damage,the twigs shrink and crack and the buds will shrink.Adults tend to repeatedly mate and oviposit,and all females lay single eggs at a time.Eggs will be covered with a mixture of secretions and wood chips by female adults.Larvae(1 st-2 nd instar)feed on the phloem,while 3 rd-5 th instar can bore into the phloem and the cambium.Massive tunnels,including three shapes(inverted"L",inverted"T",and inverted"Z"),were observed in the trunk of each tree,and resulted in swelling of the outer bark.P.tsushimanus has one life cycle per year in Shanghai.Both adults and larvae(3 rd-5 th instar)overwinter from early November to early April.Adults overwinter in grooves on the underside of branches or at branch nodes,and larvae overwinter in tunnels.Five larval instars of P.tsushimanus were determined according to Dyar’s and Crosby’s rules.The biological traits and life history of P.tsushimanus have been identified and can provide guidance in terms of pest control and plantation management.展开更多
The three-dimensional(3D)geometry of a fault is a critical control on earthquake nucleation,dynamic rupture,stress triggering,and related seismic hazards.Therefore,a 3D model of an active fault can significantly impro...The three-dimensional(3D)geometry of a fault is a critical control on earthquake nucleation,dynamic rupture,stress triggering,and related seismic hazards.Therefore,a 3D model of an active fault can significantly improve our understanding of seismogenesis and our ability to evaluate seismic hazards.Utilising the SKUA GoCAD software,we constructed detailed seismic fault models for the 2021 M_(S)6.4 Yangbi earthquake in Yunnan,China,using two sets of relocated earthquake catalogs and focal mechanism solutions following a convenient 3D fault modeling workflow.Our analysis revealed a NW-striking main fault with a high-angle SW dip,accompanied by two branch faults.Interpretation of one dataset revealed a single NNW-striking branch fault SW of the main fault,whereas the other dataset indicated four steep NNE-striking segments with a left-echelon pattern.Additionally,a third ENE-striking short fault was identified NE of the main fault.In combination with the spatial distribution of pre-existing faults,our 3D fault models indicate that the Yangbi earthquake reactivated pre-existing NW-and NE-striking fault directions rather than the surface-exposed Weixi-Qiaohou-Weishan Fault zone.The occurrence of the Yangbi earthquake demonstrates that the reactivation of pre-existing faults away from active fault zones,through either cascade or conjugate rupture modes,can cause unexpected moderate-large earthquakes and severe disasters,necessitating attention in regions like southeast Xizang,which have complex fault systems.展开更多
The complex Red River fault zone(RRFZ),which is situated in the southwestern region of China and separates the Indochina plate and South China blocks,has diverse seismic activities in different segments.To reveal the ...The complex Red River fault zone(RRFZ),which is situated in the southwestern region of China and separates the Indochina plate and South China blocks,has diverse seismic activities in different segments.To reveal the detailed geometric characteristics of the RRFZ at different sections and to better understand the seismogenic environment,in 2022 and 2023 we deployed 7 seismic dense linear arrays,consisting of 574 nodal stations,across the RRFZ in the northern and southern segments near the towns Midu,Gasa,Zhega,Dazhai,Xinzhai,and Taoyuan.The linear arrays,which extend from 2.4 to 12.5 km in length with station intervals ranging between 40 and140 m,recorded seismic ambient noise for approximately one month.Using the extended range phase shift method,we extract the phase velocity dispersion curves of the Rayleigh waves between 0.9 and 10 Hz,which are then used to invert for the high resolution shearwave velocity structures across the RRFZ beneath the linear arrays.The key findings are:(1)the 7 imaged sections of the RRFZ exhibit quite similar structures,with higher velocities on the SW side and lower velocities on the NE side;the velocity variation is consistent with the surface geological structures along the RRFZ;(2)the shear-wave velocities on the SW side of the RRFZ at the northern Midu section and southern Gasa-Dazhai sections are generally higher than their counterparts in the southern Xinzhai-Taoyuan sections,which reflects lithological variations from the marble-dominated Paleoproterozoic Along basement to the gneiss dominated Paleoproterozoic Qingshuihe basement;(3)from the northern Midu section to the southern region where the RRFZ intersects with the Xiaojiang Fault,the major faults of the RRFZ exhibit a consistent high-angle,NE-dipping structure;(4)the low shear-wave velocities immediately to the NE of the velocity boundary may indicate a faulted zone due to long-term shearing,where excessive amplifications of ground motions could occur.This study provides new insights into the characteristics of the shallow structures of the RRFZ.展开更多
The abundant muscle tissues of the forearm determine the movements of the wrist,hand and fingers together.However,linking wrist kinematics and forearm muscle activation is still a challenging.There may exist blindness...The abundant muscle tissues of the forearm determine the movements of the wrist,hand and fingers together.However,linking wrist kinematics and forearm muscle activation is still a challenging.There may exist blindness in the rehabilitation therapy of forearm muscles,due to the lack of the physiological characteristics of muscle activation and sequences.An armband with eight channels was used to collect surface electromyographic signals(sEMGs)of a specific section of the forearm under the different wrist movements,palm postures,and external loads,based on the image of magnetic resonance imaging(MRI).The collected cross-sectional muscles covered almost all surface muscles.The muscle activation could be expressed clearly by enveloping the sEMG signals of 8 muscles within a single cycle.The root mean square(RMS)and the average peak value V_(P) were used to evaluate the activation intensities of dominant muscles.The activation sequences and the absolute times of dominant muscles were obtained from the envelopes of their raw sEMGs,and not influenced by the palm postures and external loads.In addition,their RMS and V_(P) under each wrist movement increased approximate linearly with external loads.The corresponding contribution ratios were first calculated to evaluate the role played by each muscle.The well-defined data of forearm muscles could provide standard references for the rehabilitation therapy of forearm muscles.展开更多
基金supported by the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX19_1077)the Science and Technology Commission of Shanghai Municipality(18,391,903,200)the Shanghai Landscaping&City Appearance Administrative Bureau(G161206)。
文摘Cinnamomum camphora(L.)J.Presl.(Laurales:Lauraceae)is widely cultivated as an important landscape tree species in many urban areas in South China,especially in Shanghai City.Pagiophloeus tsushimanus Morimoto has become a destructive insect pest of C.camphora plantations in Shanghai,but the biological and ecological traits of this pest remain largely unknown.In this study,we investigated the damage and life history and determined the larval instar of P.tsushimanus.The results indicated that P.tsushimanus is a monophagous weevil pest,and C.camphora is the unique host tree species.C.camphora plantations in all administrative districts of Shanghai have been seriously damaged by P.tsushimanus.Adults often aggregate for feeding on the tender bark of twigs and occasionally on newly emerged buds.After experiencing damage,the twigs shrink and crack and the buds will shrink.Adults tend to repeatedly mate and oviposit,and all females lay single eggs at a time.Eggs will be covered with a mixture of secretions and wood chips by female adults.Larvae(1 st-2 nd instar)feed on the phloem,while 3 rd-5 th instar can bore into the phloem and the cambium.Massive tunnels,including three shapes(inverted"L",inverted"T",and inverted"Z"),were observed in the trunk of each tree,and resulted in swelling of the outer bark.P.tsushimanus has one life cycle per year in Shanghai.Both adults and larvae(3 rd-5 th instar)overwinter from early November to early April.Adults overwinter in grooves on the underside of branches or at branch nodes,and larvae overwinter in tunnels.Five larval instars of P.tsushimanus were determined according to Dyar’s and Crosby’s rules.The biological traits and life history of P.tsushimanus have been identified and can provide guidance in terms of pest control and plantation management.
基金financial support from the National Key R&D Program of China (No. 2021YFC3000600)National Natural Science Foundation of China (No. 41872206)National Nonprofit Fundamental Research Grant of China, Institute of Geology, China, Earthquake Administration (No. IGCEA2010)
文摘The three-dimensional(3D)geometry of a fault is a critical control on earthquake nucleation,dynamic rupture,stress triggering,and related seismic hazards.Therefore,a 3D model of an active fault can significantly improve our understanding of seismogenesis and our ability to evaluate seismic hazards.Utilising the SKUA GoCAD software,we constructed detailed seismic fault models for the 2021 M_(S)6.4 Yangbi earthquake in Yunnan,China,using two sets of relocated earthquake catalogs and focal mechanism solutions following a convenient 3D fault modeling workflow.Our analysis revealed a NW-striking main fault with a high-angle SW dip,accompanied by two branch faults.Interpretation of one dataset revealed a single NNW-striking branch fault SW of the main fault,whereas the other dataset indicated four steep NNE-striking segments with a left-echelon pattern.Additionally,a third ENE-striking short fault was identified NE of the main fault.In combination with the spatial distribution of pre-existing faults,our 3D fault models indicate that the Yangbi earthquake reactivated pre-existing NW-and NE-striking fault directions rather than the surface-exposed Weixi-Qiaohou-Weishan Fault zone.The occurrence of the Yangbi earthquake demonstrates that the reactivation of pre-existing faults away from active fault zones,through either cascade or conjugate rupture modes,can cause unexpected moderate-large earthquakes and severe disasters,necessitating attention in regions like southeast Xizang,which have complex fault systems.
基金funded by the National Key Research and Development Project of China(Grant No.2021YFC3000600)the China Earthquake Science Experiment Field-Cross-fault Observation Array-Red River Fault Scientific Drilling Project Geophysical Prospecting Site Selection Project+2 种基金Anhui Province Science and Technology Breakthrough Plan Project(Key Project,202423l10050030)the Earthquake Science and Technology Spark Program of the China Earthquake Administration(XH23020YA)the Anhui Mengcheng National Geophysical Observatory Joint Open Fund(MENGO-202307)。
文摘The complex Red River fault zone(RRFZ),which is situated in the southwestern region of China and separates the Indochina plate and South China blocks,has diverse seismic activities in different segments.To reveal the detailed geometric characteristics of the RRFZ at different sections and to better understand the seismogenic environment,in 2022 and 2023 we deployed 7 seismic dense linear arrays,consisting of 574 nodal stations,across the RRFZ in the northern and southern segments near the towns Midu,Gasa,Zhega,Dazhai,Xinzhai,and Taoyuan.The linear arrays,which extend from 2.4 to 12.5 km in length with station intervals ranging between 40 and140 m,recorded seismic ambient noise for approximately one month.Using the extended range phase shift method,we extract the phase velocity dispersion curves of the Rayleigh waves between 0.9 and 10 Hz,which are then used to invert for the high resolution shearwave velocity structures across the RRFZ beneath the linear arrays.The key findings are:(1)the 7 imaged sections of the RRFZ exhibit quite similar structures,with higher velocities on the SW side and lower velocities on the NE side;the velocity variation is consistent with the surface geological structures along the RRFZ;(2)the shear-wave velocities on the SW side of the RRFZ at the northern Midu section and southern Gasa-Dazhai sections are generally higher than their counterparts in the southern Xinzhai-Taoyuan sections,which reflects lithological variations from the marble-dominated Paleoproterozoic Along basement to the gneiss dominated Paleoproterozoic Qingshuihe basement;(3)from the northern Midu section to the southern region where the RRFZ intersects with the Xiaojiang Fault,the major faults of the RRFZ exhibit a consistent high-angle,NE-dipping structure;(4)the low shear-wave velocities immediately to the NE of the velocity boundary may indicate a faulted zone due to long-term shearing,where excessive amplifications of ground motions could occur.This study provides new insights into the characteristics of the shallow structures of the RRFZ.
基金Supported by National Natural Science Foundation of China(Grant Nos.52375279,52175001)Beijing Natural Science Foundation(Grant No.3252002).
文摘The abundant muscle tissues of the forearm determine the movements of the wrist,hand and fingers together.However,linking wrist kinematics and forearm muscle activation is still a challenging.There may exist blindness in the rehabilitation therapy of forearm muscles,due to the lack of the physiological characteristics of muscle activation and sequences.An armband with eight channels was used to collect surface electromyographic signals(sEMGs)of a specific section of the forearm under the different wrist movements,palm postures,and external loads,based on the image of magnetic resonance imaging(MRI).The collected cross-sectional muscles covered almost all surface muscles.The muscle activation could be expressed clearly by enveloping the sEMG signals of 8 muscles within a single cycle.The root mean square(RMS)and the average peak value V_(P) were used to evaluate the activation intensities of dominant muscles.The activation sequences and the absolute times of dominant muscles were obtained from the envelopes of their raw sEMGs,and not influenced by the palm postures and external loads.In addition,their RMS and V_(P) under each wrist movement increased approximate linearly with external loads.The corresponding contribution ratios were first calculated to evaluate the role played by each muscle.The well-defined data of forearm muscles could provide standard references for the rehabilitation therapy of forearm muscles.
