Objective In kinesin-3,the neck coil correlates with the following segments to form an extended neck that contains a characteristic hinge diverse from a proline in KIF13B to a long flexible linker in KIF1A.The functio...Objective In kinesin-3,the neck coil correlates with the following segments to form an extended neck that contains a characteristic hinge diverse from a proline in KIF13B to a long flexible linker in KIF1A.The function of this neck hinge for controlling processive movement,however,remains unclear.Methods We made a series of modifications to the neck hinges of KIF13B and KIF1A and tested their movement using a single-molecule motility assay.Results In KIF13B,the insertion of flexible residues before or after the proline differentially impacts the processivity or velocity,while the removal of this proline increases the both.In KIF1A,the deletion of entire flexible neck hinge merely enhances the processivity.The engineering of these hinge-truncated necks of kinesin-3 into kinesin-1 similarly boosts the processive movement of kinesin-1.Conclusion The neck hinge in kinesin-3 controls its processive movement and proper modifications tune the motor motility,which provides a novel strategy to reshape the processive movement of kinesin motors.展开更多
Accurate dynamic modeling of landslides could help understand the movement mechanisms and guide disaster mitigation and prevention.Discontinuous deformation analysis(DDA)is an effective approach for investigating land...Accurate dynamic modeling of landslides could help understand the movement mechanisms and guide disaster mitigation and prevention.Discontinuous deformation analysis(DDA)is an effective approach for investigating landslides.However,DDA fails to accurately capture the degradation in shear strength of rock joints commonly observed in high-speed landslides.In this study,DDA is modified by incorporating simplified joint shear strength degradation.Based on the modified DDA,the kinematics of the Baige landslide that occurred along the Jinsha River in China on 10 October 2018 are reproduced.The violent starting velocity of the landslide is considered explicitly.Three cases with different violent starting velocities are investigated to show their effect on the landslide movement process.Subsequently,the landslide movement process and the final accumulation characteristics are analyzed from multiple perspectives.The results show that the violent starting velocity affects the landslide motion characteristics,which is found to be about 4 m/s in the Baige landslide.The movement process of the Baige landslide involves four stages:initiation,high-speed sliding,impact-climbing,low-speed motion and accumulation.The accumulation states of sliding masses in different zones are different,which essentially corresponds to reality.The research results suggest that the modified DDA is applicable to similar high-level rock landslides.展开更多
In this paper,the data of vertical crustal deformations associated with the Xingtai,Haicheng,Tangshan and Datong strong earthquakes in North China Block have been processed,analyzed and studied.The result shows that t...In this paper,the data of vertical crustal deformations associated with the Xingtai,Haicheng,Tangshan and Datong strong earthquakes in North China Block have been processed,analyzed and studied.The result shows that the seismogenic processes of strong earthquakes are accompanied by an evolution of crustal deformation as follows: ① The area of crustal deformation anomaly should be large in radius and extensive in range. ② There are both the 'field' and 'source' of crustal deformation anomaly,with the 'source' existing inside the'field' but differing from the 'field' distinctly. ③ The evolution process includes a number of steps.Firstly, movements in the 'field region transform from the normal state to an anomalous state to start the formation of field precursors.Secondly,movements in the 'source' region become outstandingly remarkable. Thirdly,anomalies in the 'field' region that surrounds the 'source' become increasingly intense.Fourthly,the 'source' region enters a state of immobilized-movement.Finally,an earthquake occurs. ④ There are usually one or more areas where the anomaly field forms a special pattern,mostly a four-quadrant distribution.The area which is'activated' first but becomes 'immobilized' afterwards often coincides with the source area.⑤ The appearance of an obviously immobilized area inside the obviously activated area is a precursory feature which suggests that an earthquake is impending.⑥ The longer the duration of immobilized-movement,the higher the magnitude of earthquake would be.The above might be the basic mode of vertical crustal deformation during the seismogenic process of strong intraplate earthquakes.展开更多
Neotectonic movement refers to the tectonic movement that has happened since the Cenozoic, which is the latest movement. It has the most important influence on the basins in west China, especially on the hydrocarbon a...Neotectonic movement refers to the tectonic movement that has happened since the Cenozoic, which is the latest movement. It has the most important influence on the basins in west China, especially on the hydrocarbon accumulation in the western foreland basins. We determined the time of neotectonic movement in the Kuqa Foreland Basin, which began from the Neogene, and analyzed the patterns of movement, which were continuous and fast subsidence in the vertical direction and intense lateral compression. The structure styles are that the faulting is weakened and the folding is strengthened gradually from north to south. We studied the control of neotectonic movement on the hydrocarbon accumulation process and model in the Kuqa Foreland Basin with basin simulation technique. The largest subsidence rate of the Kuqa Foreland Basin reached 1,200 m/Ma during the neotectonic movement, leading to rapid maturing of source rock within 5 Ma and a large quantity of hydrocarbon being generated and expelled. The thick neotectonic strata can form high quality reservoirs with the proved gas and oil reserves accounting for 5% and 27% of the total reserves, respectively. 86% of the structural traps were formed in the neotectonic movement period. The faults formed during the neotectonic movement serve as important migration pathways and they exist in the region where the hydrocarbon reservoirs are distributed. Abnormally high pressure caused by the intense lateral compression, thick neotectonic strata deposition and rapid hydrocarbon generation provide driving force for hydrocarbon migration. The accumulation elements match each other well over a short period, leading to many large gas fields formed later in the Kuqa Foreland Basin.展开更多
It is argued that research on eye movements has now entered a fourth general era. Each of the four eras is briefly reviewed, and research findings related to eye movements during reading, scene perception, and visual ...It is argued that research on eye movements has now entered a fourth general era. Each of the four eras is briefly reviewed, and research findings related to eye movements during reading, scene perception, and visual search are discussed. Future directions for research in each of these areas and research in other domains involving eye movements are also discussed.展开更多
This study investigates the physical conditions(water depth, current speed, salinity, temperature) in Lianzhou Bay, a shallow coastal bay in southern China, during two expeditions in the dry and wet seasons of 2011. B...This study investigates the physical conditions(water depth, current speed, salinity, temperature) in Lianzhou Bay, a shallow coastal bay in southern China, during two expeditions in the dry and wet seasons of 2011. Based on these expedition data, basic hydrodynamic parameters like Brunt-V?is?l? Frequency, Richardson Number, Rossby radius, and Resonance Period are calculated. The results show that Lianzhou Bay is characterized by comparatively small quantity of freshwater input and weak stratification. Strong tides, which are spatially uniform within the bay, cause turbulent mixing. Residence time of the water is shorter in winter due to a stronger coastal current in that season. Consideration of the water movement may help to reduce the harmful ecological impact of aquaculture waste water discharge.展开更多
文摘Objective In kinesin-3,the neck coil correlates with the following segments to form an extended neck that contains a characteristic hinge diverse from a proline in KIF13B to a long flexible linker in KIF1A.The function of this neck hinge for controlling processive movement,however,remains unclear.Methods We made a series of modifications to the neck hinges of KIF13B and KIF1A and tested their movement using a single-molecule motility assay.Results In KIF13B,the insertion of flexible residues before or after the proline differentially impacts the processivity or velocity,while the removal of this proline increases the both.In KIF1A,the deletion of entire flexible neck hinge merely enhances the processivity.The engineering of these hinge-truncated necks of kinesin-3 into kinesin-1 similarly boosts the processive movement of kinesin-1.Conclusion The neck hinge in kinesin-3 controls its processive movement and proper modifications tune the motor motility,which provides a novel strategy to reshape the processive movement of kinesin motors.
基金supported by the National Natural Science Foundations of China(grant numbers U22A20601 and 52209142)the Opening fund of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(Chengdu University of Technology)(grant number SKLGP2022K018)+1 种基金the Science&Technology Department of Sichuan Province(grant number 2023NSFSC0284)the Science and Technology Major Project of Tibetan Autonomous Region of China(grant number XZ202201ZD0003G)。
文摘Accurate dynamic modeling of landslides could help understand the movement mechanisms and guide disaster mitigation and prevention.Discontinuous deformation analysis(DDA)is an effective approach for investigating landslides.However,DDA fails to accurately capture the degradation in shear strength of rock joints commonly observed in high-speed landslides.In this study,DDA is modified by incorporating simplified joint shear strength degradation.Based on the modified DDA,the kinematics of the Baige landslide that occurred along the Jinsha River in China on 10 October 2018 are reproduced.The violent starting velocity of the landslide is considered explicitly.Three cases with different violent starting velocities are investigated to show their effect on the landslide movement process.Subsequently,the landslide movement process and the final accumulation characteristics are analyzed from multiple perspectives.The results show that the violent starting velocity affects the landslide motion characteristics,which is found to be about 4 m/s in the Baige landslide.The movement process of the Baige landslide involves four stages:initiation,high-speed sliding,impact-climbing,low-speed motion and accumulation.The accumulation states of sliding masses in different zones are different,which essentially corresponds to reality.The research results suggest that the modified DDA is applicable to similar high-level rock landslides.
文摘In this paper,the data of vertical crustal deformations associated with the Xingtai,Haicheng,Tangshan and Datong strong earthquakes in North China Block have been processed,analyzed and studied.The result shows that the seismogenic processes of strong earthquakes are accompanied by an evolution of crustal deformation as follows: ① The area of crustal deformation anomaly should be large in radius and extensive in range. ② There are both the 'field' and 'source' of crustal deformation anomaly,with the 'source' existing inside the'field' but differing from the 'field' distinctly. ③ The evolution process includes a number of steps.Firstly, movements in the 'field region transform from the normal state to an anomalous state to start the formation of field precursors.Secondly,movements in the 'source' region become outstandingly remarkable. Thirdly,anomalies in the 'field' region that surrounds the 'source' become increasingly intense.Fourthly,the 'source' region enters a state of immobilized-movement.Finally,an earthquake occurs. ④ There are usually one or more areas where the anomaly field forms a special pattern,mostly a four-quadrant distribution.The area which is'activated' first but becomes 'immobilized' afterwards often coincides with the source area.⑤ The appearance of an obviously immobilized area inside the obviously activated area is a precursory feature which suggests that an earthquake is impending.⑥ The longer the duration of immobilized-movement,the higher the magnitude of earthquake would be.The above might be the basic mode of vertical crustal deformation during the seismogenic process of strong intraplate earthquakes.
基金supported by the Foundation Project of State Key Laboratory of Petroleum Resources and Prospecting (PRPDX2008-05)the "973" National Key Basic Research Program (2006CB202308)
文摘Neotectonic movement refers to the tectonic movement that has happened since the Cenozoic, which is the latest movement. It has the most important influence on the basins in west China, especially on the hydrocarbon accumulation in the western foreland basins. We determined the time of neotectonic movement in the Kuqa Foreland Basin, which began from the Neogene, and analyzed the patterns of movement, which were continuous and fast subsidence in the vertical direction and intense lateral compression. The structure styles are that the faulting is weakened and the folding is strengthened gradually from north to south. We studied the control of neotectonic movement on the hydrocarbon accumulation process and model in the Kuqa Foreland Basin with basin simulation technique. The largest subsidence rate of the Kuqa Foreland Basin reached 1,200 m/Ma during the neotectonic movement, leading to rapid maturing of source rock within 5 Ma and a large quantity of hydrocarbon being generated and expelled. The thick neotectonic strata can form high quality reservoirs with the proved gas and oil reserves accounting for 5% and 27% of the total reserves, respectively. 86% of the structural traps were formed in the neotectonic movement period. The faults formed during the neotectonic movement serve as important migration pathways and they exist in the region where the hydrocarbon reservoirs are distributed. Abnormally high pressure caused by the intense lateral compression, thick neotectonic strata deposition and rapid hydrocarbon generation provide driving force for hydrocarbon migration. The accumulation elements match each other well over a short period, leading to many large gas fields formed later in the Kuqa Foreland Basin.
文摘It is argued that research on eye movements has now entered a fourth general era. Each of the four eras is briefly reviewed, and research findings related to eye movements during reading, scene perception, and visual search are discussed. Future directions for research in each of these areas and research in other domains involving eye movements are also discussed.
基金the financial support from the German Federal Ministry for Education and Research(BMBF)to the Leibniz-Zentrum für Marine Tropenkologie GmbH(ZMT),Germany,for the project‘The Role of Mangroves for Biogeochemical Fluxes into the Coastal Ecosystemsunder the Influence of Anthropogenic Alterations’as part of the Sino-German Research Project‘BEIBU-Holocene environmental evolution and anthropogenic impact of Beibu Gulf,South China Sea’,WTZ China(Grant No.03F0607B) is acknowledged.
文摘This study investigates the physical conditions(water depth, current speed, salinity, temperature) in Lianzhou Bay, a shallow coastal bay in southern China, during two expeditions in the dry and wet seasons of 2011. Based on these expedition data, basic hydrodynamic parameters like Brunt-V?is?l? Frequency, Richardson Number, Rossby radius, and Resonance Period are calculated. The results show that Lianzhou Bay is characterized by comparatively small quantity of freshwater input and weak stratification. Strong tides, which are spatially uniform within the bay, cause turbulent mixing. Residence time of the water is shorter in winter due to a stronger coastal current in that season. Consideration of the water movement may help to reduce the harmful ecological impact of aquaculture waste water discharge.