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Salt-Water Transport in Unsaturated Soils Under Crop Planting: Dynamics and Numerical Simulation 被引量:7
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作者 XU Li-Gang YANG Jing-Song +1 位作者 ZHANG Qi LIU Guang-Ming 《Pedosphere》 SCIE CAS CSCD 2005年第5期634-640,共7页
A laboratory salt-water dynamics experiment using unsaturated soils in packed silt loam and clay soil columns withdifferent soil texture profiles and groundwater levels under crops were conducted to study the changes ... A laboratory salt-water dynamics experiment using unsaturated soils in packed silt loam and clay soil columns withdifferent soil texture profiles and groundwater levels under crops were conducted to study the changes of salt-waterdynamics induced by water uptake of crops and to propose the theoretical basis for the regulation and control of salt-water dynamics as well as to predict salinity levels. The HYDRUS 1D model was applied to simulate the one-dimensionalmovement of water and salt transport in the soil columns. The results showed that the salts mainly accumulated in theplow layer in the soil columns under crops. Soil water and salt both moved towards the plow layer due to soil waterabsorption by the crop root system. The salt contents in the column with lower groundwater were mostly greater thanthose with high groundwater. The water contents in the soil columns increased from top to the bottom due to plant rootwater uptake. The changes in groundwater level had little influence on water content of the root zone in the soil columnswith crop planting. Comparison between the simulated and the determined values showed that model simulation resultswere ideal, so it is practicable to do numerical simulation of soil salt and water transport by the HYDRUS 1D model.Furthermore, if the actual movement of salt and water in fields is to be described in detail, much work needs to be done.The most important thing is to refine the parameters and select precise boundary conditions. 展开更多
关键词 crop planting numerical simulation salt accumulation salt-water dynamics
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Salt-Water Dynamics in Soils: II. Effect of Precipitation on Salt-Water Dynamics 被引量:6
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作者 YOUWEN-RUI MENGFAN-HUA 《Pedosphere》 SCIE CAS CSCD 1992年第4期289-306,共18页
Through a simulation test carried out with soil columns (61.8 cm in diameter), the effect of precipitation on salt-water dynamics in soils was studied by in-situ monitoring of salt-water dynamics using soil salinity s... Through a simulation test carried out with soil columns (61.8 cm in diameter), the effect of precipitation on salt-water dynamics in soils was studied by in-situ monitoring of salt-water dynamics using soil salinity sensors and tensiometers. The results show that in the profile of whole silty loam soil, the surface runoff volume due to precipitation and the salt-leaching role of infiltrated precipitation increased with the depth of ground water; and in the profile with an intercalated bed of clay or with a thick upper layer of clay, the amount of surface runoff was greater but the salt-leaching role of precipitation was smaller than those in the profile of whole silty loam soil. In case of soil water being supplemented by precipitation, the evaporation of groundwater in the soil columns reduced, resulting in a great decline of salt accumulation from soil profile to surface soil. The effect of precipitation on the water regime of soil profile was performed via both water infiltration and water pressure transfer. The direct infiltration depth of precipitation was less than 1 m in general, but water pressure transfer could go up to groundwater surface directly. 展开更多
关键词 groundwater evaporation precipitation infiltration salt-water dynamics salt-leaching surface runoff
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Salt-Water Dynamics in Highly Salinized Topsoil of Salt-Affected Soil During Water Infiltration 被引量:4
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作者 WANGXUE-FENG YOUWEN-RUI 《Pedosphere》 SCIE CAS CSCD 1991年第4期315-323,共9页
Continuous monitoring of salt and water movement in the soil profile of highly salinized topsoil under steadystate infiltration was conducted.It gives that salt and water dynamics during convection-diffusion period ca... Continuous monitoring of salt and water movement in the soil profile of highly salinized topsoil under steadystate infiltration was conducted.It gives that salt and water dynamics during convection-diffusion period can be divided into three stages:1.formation of a salt peak,2.the salt peak moving downwards till the appearance of the summit of the salt peak,3.the salt peak moving further downwards with the peak value decreasing.Results show that the maximum salt peak appears at the same depth if soil texture and outflow condition are the same.Factors affecting salt and water movement and ion components in the outflow solution underinfiltration are discussed. 展开更多
关键词 INFILTRATION SALINE salt peak salt-water dynamics
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Salt-Water Dynamics in Soils: Ⅰ. Salt-Water Dynamics in Unsaturated Soils Under Stable Evaporation Condition 被引量:3
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作者 YOUWEN-RUI MENGFAN-HUA 《Pedosphere》 SCIE CAS CSCD 1992年第3期219-235,共17页
A long term simulation test on salt-water dynamics in unsaturated soils with different groundwater depths and soil texture profiles under stable evaporation condition was conducted.Salinity sensors and tensiometers we... A long term simulation test on salt-water dynamics in unsaturated soils with different groundwater depths and soil texture profiles under stable evaporation condition was conducted.Salinity sensors and tensiometers were used to monitor salt and water variation in soils.The experiment revealed that in the process of fresh groundwater moving upwards by capillary rise in the column,the salts in subsoil were brought upwards and accumulated in the surface soil,and consequently the salinization of surface soil took place.The rate of salt accumulation is determined mainly by the volume of capillary water flow and the conditions of salts contained in the soil profile.Water flux in soils decreased obviously when groundwater depths fell below 1.5m.When there was an interbedded clay layer 30cm in thickness in the silty loam soil profile or a clay layer 100cm in thickness at the top layer,the water flux was 3-5 times less than in the soil profile of homogeneous silty loam soil.Therefore,the rate of salt accumulation was decreased and the effect of variation of groundwater depth on the water flux in soils was weakened comparatively.If there was precipitation or irrigation supplying water to the soil,the groundwater could rarely take a direct part in the process of salt accumulation in surface soil,especially,in soil profiles with an interbedded stratum or a clayey surface soil layer. 展开更多
关键词 evaporation condition salt accumulation salt-water dynamics
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Salt-Water Dynamics in Soils:Ⅲ.Effect of Crop Planting 被引量:3
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作者 YOUWEN-RUI MENGFAN-HUA 《Pedosphere》 SCIE CAS CSCD 1993年第1期7-22,共16页
Through a simulation test conducted with soil columns (61.8cm in diameter) in field condition,effect of crop planting upon the regulation of salt-water dynamics in soils was studied by monitoring of salt-water dynamic... Through a simulation test conducted with soil columns (61.8cm in diameter) in field condition,effect of crop planting upon the regulation of salt-water dynamics in soils was studied by monitoring of salt-water dynamics in situ,using soil salinity sensors and tensiometers.The results indicated that the amount of water absorbed by crops from the soil was generally larger than the decrement of water consumption from soil surface evaporation reduced by the crop covering the soil surface and improving the soil structure,therefore,under the conditions of crop growing and non-irrigation,water content in soil profile was less than that without crop growing,and the gradient of negative pressure of soil water in soil profile especially in the root zone was enlarged,thus causing the water flowing from subsoils into root zone and increasing the groundwater moving upwards into soil layer via capillary rise,so that the groundwater evaporation increased.Consequently,under the condition of crop growing,the salt was mainly accumulated towards the root zone rather than to the top soil.the accumulating rate of salt in groundwater via capillary rise of soil water to subsoils was increased thereby. 展开更多
关键词 groundwater evaporation salt-water dynamics water regime
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Environmental evolution in the salt-water intrusion area south of Laizhou Bay since late Pleistocene 被引量:4
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作者 ZHANG Zulu LIU Enfeng +1 位作者 ZHANG Yan XIN Liangjie 《Journal of Geographical Sciences》 SCIE CSCD 2008年第1期37-45,共9页
The south coastal plain of Laizhou Bay is one of the typical salt-water intrusion areas in China, the occurrence and development of which was closely related with the palaeoenvironment evolution. Systematic analyses o... The south coastal plain of Laizhou Bay is one of the typical salt-water intrusion areas in China, the occurrence and development of which was closely related with the palaeoenvironment evolution. Systematic analyses of pollen, foraminifera and grain size composition based on ^14C and luminescence dating from two sediment cores were performed for the purpose of understanding the salt-water intrusion in the coastal plain of Laizhou Bay from the perspective of environmental evolution since late Pleistocene. It could be classified into seven evolution stages since 120 kaBP: 120-85 kaBP was a transition period from cold to warm; 85-76 kaBP was a period with warm and wet climate having swamp lakes developed in the lower reaches of the Weihe River, south coastal plain of Laizhou Bay; 76-50 kaBP was characterized by grassland vegetation and coarse sediments in terrestrial environment, which was the early stage of Dali Ice-Age; 50-24 kaBP was a period with alternate sea deposition in the south coastal plain of Laizhou Bay; 24-10 kaBP was the late stage of Dali Ice-Age with coldest period of Quaternary, the south coastal plain of Laizhou Bay was dry grassland and loess deposition environment; 10-4 kaBP was another warm and wet climate period, sea level was high and regressed at 4 kaBP; and has been the modern sedimentary environment since 4 kaBP. Among the three warm stages, including 85-76 kaBP, 50-24 kaBP and 10-4 kaBP, corresponded to late Yangkou, Guangrao and Kenli seawater transgression respectively. The duration of the latter one in south coastal plain of Laizhou Bay was longer than that in west coast of Bohai Sea and east coast of Laizhou Bay. The three periods of seawater transgression formed the foundation of salt-water intrusion in this area. 展开更多
关键词 environmental evolution salt-water intrusion late Pleistocene south coastal plain of Laizhou Bay China
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Phase Equilibria of Salt-water Systems Containing Magnesium and Borate Ions
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作者 HAN Xunian GUO Yafei +1 位作者 WANG Shiqiang DENG Tianlong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期331-332,共2页
1 Introduction A salt lake is a naturally occurring complex body of water and salt interaction.More than 700 salt lakes are widely distributed in the area of the Qinghai-Tibet Plateau.Most of the salt lakes are famous... 1 Introduction A salt lake is a naturally occurring complex body of water and salt interaction.More than 700 salt lakes are widely distributed in the area of the Qinghai-Tibet Plateau.Most of the salt lakes are famous for their abundance of lithium,potassium,magnesium,and boron resources.It is 展开更多
关键词 salt-water system phase equilibrium MAGNESIUM BORATE
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Association between Meeting 24-Hour Movement Guidelines and Psychological Features of Chinese Emerging Adults 被引量:1
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作者 Yanjie Zhang Jin Kuang +2 位作者 Xun Luo Mengxian Zhao Xiaolei Liu 《International Journal of Mental Health Promotion》 2024年第5期399-406,共8页
Background:Emerging adulthood is a pivotal life stage,presenting significant psychological and social changes,such as decreased sociability,depression,and other mental health problems.Previous studies have associated ... Background:Emerging adulthood is a pivotal life stage,presenting significant psychological and social changes,such as decreased sociability,depression,and other mental health problems.Previous studies have associated these changes with an unhealthy lifestyle.The 24-h movement guidelines for healthy lifestyles have been developed to promote appropriate health behaviors and improve individual wellness.However,the relationship between adherence to the 24-h movement guidelines and different characteristics of Chinese emerging adults is yet to be explored.This cross-sectional study aimed to investigate the association between adherence to the 24-h movement guidelines and four characteristics(self-exploration,instability,possibilities,and responsibility)of Chinese emerging adults.Methods:Overall,1,510 Chinese emerging adults aged 18–29 years were included in this study.Each participant completed a self-administered questionnaire that included questions on adherence to the 24-h movement guidelines(physical activity,sedentary behavior,and sleep)and the inventory of dimensions of emerging adulthood.Multivariable logistic regression analysis was employed to investigate the associations between adherence to the 24-h movement guidelines and each of the four characteristics.Results:The proportion of participants who adhered to the 24-h movement guidelines was 31.72%.Multiple regression analysis revealed a significantly negative relationship between adhering to more guidelines and instability(β=−0.51,p<0.001).A statistically significant association was observed between instability and meeting only sedentary behavior(β=−1.27,95%confidence interval[CI]:[−2.32,−0.24],p=0.02),sedentary behavior+sleep(β=−1.30,95%CI:[−2.24,−0.35],p<0.01),and physical activity+sedentary behavior(β=−1.08,95%CI:[1.94,−0.21],p=0.02)guidelines.Further,positive and significant associations were observed between possibilities and meeting the guidelines for only physical activity(β=0.70,95%CI:[0.14,1.27),p=0.01),only sleep(β=0.61,95%CI:[0.01,1.21],p=0.04),physical activity+sedentary behavior(β=0.56,95%CI:[0.04,1.07),p=0.01),and physical activity+sleep(β=0.76,95%CI:[0.23,1.27],p=0.01).Conclusions:These findings suggest that adherence to the 24-h movement guidelines was associated with instability in Chinese emerging adults.Future studies are warranted to verify our findings to highlight the importance of maintaining a heath lifestyle to promote health in emerging adulthood. 展开更多
关键词 24-h movement behavior physical activity sedentary behavior SLEEP psychological health emerging adults
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Assessment of International GNSS Service Global Ionosphere Map products over China region based on measurements from the Crustal Movement Observation Network of China 被引量:1
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作者 Jin Hu HaiBing Ruan +2 位作者 FuQing Huang ShengYang Gu XianKang Dou 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期400-407,共8页
The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical application.Assessing the credibility of G... The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical application.Assessing the credibility of GIM products in data-sparse regions is of paramount importance.In this study,measurements from the Crustal Movement Observation Network of China(CMONOC)are leveraged to evaluate the suitability of IGS-GIM products over China region in 2013-2014.The indices of mean error(ME),root mean square error(RMSE),and normalized RMSE(NRMSE)are then utilized to quantify the accuracy of IGS-GIM products.Results revealed distinct local time and latitudinal dependencies in IGS-GIM errors,with substantially high errors at nighttime(NRMSE:39%)and above 40°latitude(NRMSE:49%).Seasonal differences also emerged,with larger equinoctial deviations(NRMSE:33.5%)compared with summer(20%).A preliminary analysis implied that the irregular assimilation of sparse IGS observations,compounded by China’s distinct geomagnetic topology,may manifest as error variations.These results suggest that modeling based solely on IGS-GIM observations engenders inadequate representations across China and that a thorough examination would proffer the necessary foundation for advancing regional total electron content(TEC)constructions. 展开更多
关键词 International GNSS Service(IGS)Global Ionosphere Maps(GIM) Crustal movement Observation Network of China(CMONOC) total electron content(TEC) data assessment
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Force-induced Caspase-1-dependent pyroptosis regulates orthodontic tooth movement
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作者 Liyuan Chen Huajie Yu +11 位作者 Zixin Li Yu Wang Shanshan Jin Min Yu Lisha Zhu Chengye Ding Xiaolan Wu Tianhao Wu Chunlei Xun Yanheng Zhou Danqing He Yan Liu 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第2期238-250,共13页
Pyroptosis,an inflammatory caspase-dependent programmed cell death,plays a vital role in maintaining tissue homeostasis and activating inflammatory responses.Orthodontic tooth movement(OTM)is an aseptic force-induced ... Pyroptosis,an inflammatory caspase-dependent programmed cell death,plays a vital role in maintaining tissue homeostasis and activating inflammatory responses.Orthodontic tooth movement(OTM)is an aseptic force-induced inflammatory bone remodeling process mediated by the activation of periodontal ligament(PDL)progenitor cells.However,whether and how force induces PDL progenitor cell pyroptosis,thereby influencing OTM and alveolar bone remodeling remains unknown.In this study,we found that mechanical force induced the expression of pyroptosis-related markers in rat OTM and alveolar bone remodeling process.Blocking or enhancing pyroptosis level could suppress or promote OTM and alveolar bone remodeling respectively.Using Caspase-1^(−/−)mice,we further demonstrated that the functional role of the force-induced pyroptosis in PDL progenitor cells depended on Caspase-1.Moreover,mechanical force could also induce pyroptosis in human ex-vivo force-treated PDL progenitor cells and in compressive force-loaded PDL progenitor cells in vitro,which influenced osteoclastogenesis.Mechanistically,transient receptor potential subfamily V member 4 signaling was involved in force-induced Caspase-1-dependent pyroptosis in PDL progenitor cells.Overall,this study suggested a novel mechanism contributing to the modulation of osteoclastogenesis and alveolar bone remodeling under mechanical stimuli,indicating a promising approach to accelerate OTM by targeting Caspase-1. 展开更多
关键词 HOMEOSTASIS movement thereby
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Olympic Games and 24-hour movement behaviors:A match worth making
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作者 Mark S.Tremblay Nicholas Kuzik +1 位作者 Markus J.Duncan Diego Augusto Santos Silva 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第6期728-731,共4页
1.Background The Olympic motto,"Faster,Higher,Stronger-Together",represents the pursuit of athletic excellence,united as a global community."Excellence,respect and friendship"are the Olympic values... 1.Background The Olympic motto,"Faster,Higher,Stronger-Together",represents the pursuit of athletic excellence,united as a global community."Excellence,respect and friendship"are the Olympic values.Both the motto and values are multifaceted and holistic in nature,and all-encompassing in their reach while recognizing no single entity rises above the others.Collectively,these foundational statements anchor the Olympic movement in its quest to build a better world through sport. 展开更多
关键词 movement TOGETHER PURSUIT
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The osteoclastic activity in apical distal region of molar mesial roots affects orthodontic tooth movement and root resorption in rats
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作者 Wenhao Zheng Xiaofeng Lu +9 位作者 Guangjin Chen Yufeng Shen Xiaofei Huang Jinfeng Peng Jiajia Wang Ying Yin Wencheng Song Mengru Xie Shaoling Yu Lili Chen 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第2期322-332,共11页
The utilization of optimal orthodontic force is crucial to prevent undesirable side effects and ensure efficient tooth movement during orthodontic treatment.However,the sensitivity of existing detection techniques is ... The utilization of optimal orthodontic force is crucial to prevent undesirable side effects and ensure efficient tooth movement during orthodontic treatment.However,the sensitivity of existing detection techniques is not sufficient,and the criteria for evaluating optimal force have not been yet established.Here,by employing 3D finite element analysis methodology,we found that the apical distal region(A-D region)of mesial roots is particularly sensitive to orthodontic force in rats.Tartrate-resistant acidic phosphatase(TRAP)-positive osteoclasts began accumulating in the A-D region under the force of 40 grams(g),leading to alveolar bone resorption and tooth movement.When the force reached 80 g,TRAP-positive osteoclasts started appearing on the root surface in the A-D region.Additionally,micro-computed tomography revealed a significant root resorption at 80 g.Notably,the A-D region was identified as a major contributor to whole root resorption.It was determined that 40 g is the minimum effective force for tooth movement with minimal side effects according to the analysis of tooth movement,inclination,and hyalinization.These findings suggest that the A-D region with its changes on the root surface is an important consideration and sensitive indicator when evaluating orthodontic forces for a rat model.Collectively,our investigations into this region would aid in offering valuable implications for preventing and minimizing root resorption during patients’orthodontic treatment. 展开更多
关键词 movement ROOTS offering
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Towards precision 24-hour movement behavior recommendations—The next new paradigm?
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作者 Mark S.Tremblay Markus J.Duncan +2 位作者 Nicholas Kuzik Diego Augusto Santos Silva Valerie Carson 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第6期743-748,共6页
1.Background The importance of physical activity(PA)for health is unequivocal.^(1)Accordingly,population-based recommendations for exercise,and more recently public health guidelines for PA,have been developed and rel... 1.Background The importance of physical activity(PA)for health is unequivocal.^(1)Accordingly,population-based recommendations for exercise,and more recently public health guidelines for PA,have been developed and released by authoritative groups for many decades.^(2)Such guidelines emerged with leadership from the exercise physiology discipline and were rooted in,and loyal to,the importance of moderate-to-vigorous intensity PA(MVPA)or exercise. 展开更多
关键词 movement behavior EXERCISE
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Modifying the progression of Parkinson's disease through movement interventions:multimodal quantification of underlying mechanisms
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作者 Manuel Bange Damian Marc Herz +2 位作者 Dumitru Ciolac Gabriel Gonzalez-Escamilla Sergiu Groppa 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1651-1652,共2页
Introduction:Parkinson’s disease(PD)is the most common neurodegenerative movement disorder.The pathological hallmark is the progressive loss of dopaminergic neurons of the substantia nigra pars compacta,which is acco... Introduction:Parkinson’s disease(PD)is the most common neurodegenerative movement disorder.The pathological hallmark is the progressive loss of dopaminergic neurons of the substantia nigra pars compacta,which is accompanied by widespread alterations in the structu re and function of distributed brain networks.Togethe r,these processes cause a variety of motor symptoms such as bradykinesia,rigidity,tremor,gait disorders,or difficulties in fine motor control(Bange et al.,2022). 展开更多
关键词 alterations movement
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Dual roles of the amygdala-hippocampus circuit in the regulation of rapid eye movement sleep and depression symptoms by repetitive transcranial magnetic stimulation in patients with insomnia
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作者 Xiaoyang Liu Xumeng Zhao +7 位作者 Ziqiang Shao Yongjian Guo Lirong Yue Jiayi Liu Dahua Yu Xiaona Sheng Yifei Zhu Kai Yuan 《General Psychiatry》 CSCD 2024年第2期297-300,共4页
To the editor:It is commonly reported that people with insomnia often experience comorbid emotional disorders,such as mood and anxiety disorders.12 A study found that fragmented rapid eye movement(REM)sleep in individ... To the editor:It is commonly reported that people with insomnia often experience comorbid emotional disorders,such as mood and anxiety disorders.12 A study found that fragmented rapid eye movement(REM)sleep in individuals with insomnia is associated with higher Beck Depression Inventory(BDI)scores.3 REM sleep architecture disruption is a typical symptom of insomnia. 展开更多
关键词 SLEEP STIMULATION movement
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Engineering The Neck Hinge Reshapes The Processive Movement of Kinesin-3
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作者 LI Dong REN Jin-Qi +2 位作者 SONG Yin-Long LIANG Xin FENG Wei 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2024年第10期2730-2740,共11页
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
关键词 intracellular transport molecular motor kinesin-3 neck hinge processive movement
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Present-day movement characteristics of the Qinghai Nanshan fault and its surrounding area from GPS observation
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作者 Yang Liu Yuxuan Qiu +5 位作者 Jialiang Liu Luyun Xiong Caijun Xu Jianghui Geng Gang Zheng Tianchen Sheng 《Geodesy and Geodynamics》 EI CSCD 2024年第2期133-141,共9页
The Qinghai Nanshan fault is a larger fault in the Northeastern Xizang Plateau.In previous studies,its movement characteristics are mainly investigated with geological and seismic observations,and the tectonic transfo... The Qinghai Nanshan fault is a larger fault in the Northeastern Xizang Plateau.In previous studies,its movement characteristics are mainly investigated with geological and seismic observations,and the tectonic transformation role of the fault on its east is not yet clear.This study uses data fusion to obtain denser GPS observations near the Qinghai Nanshan fault.Based on tectonic characteristics,we establish a block model to investigate the fault slip rate,locking degree,and slip deficit.The results show that the Qinghai Nanshan fault slip rate is characterized by sinistral and convergent movement.Both the sinistral and convergent rates display a decreasing trend from west to east.The locking degree and slip deficit are higher in the western segment(with an average of about 0.74 and 1.1 mm/a)and lower in the eastern segment.Then,we construct a strain rate field using GPS observations to analyze the regional strain characteristics.The results indicate that along the fault,the western segment shows a larger shear strain rate and negative dilation rate.Regional earthquake records show that the frequency of earthquakes is lower near the fault.The joint results suggest that the western segment may have a higher earthquake risk.In addition,the insignificant fault slip rate in the eastern segment may indicate that it does not participate in the tectonic transformation among the Riyueshan,Lajishan,and West Qinling faults. 展开更多
关键词 The Qinghai Nanshan fault movement characteristics Block model Slip rate GPS
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Obtaining 2D Soil Geotechnical Profiles from Cokriging Interpolation of Sample Data and Electrical Resistivity Tomography (ERT)—Applications in Mass Movements Studies
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作者 Cassiano Antonio Bortolozo Noel Howley +11 位作者 Andy Legg Tristan Pryer Danielle Silva de Paula Tatiana Sussel Gonçalves Mendes Daniel Metodiev Marcio Roberto Magalhães de Andrade Silvio Jorge Coelho Simões Maiconn Vinicius de Moraes Marcio Augusto Ernesto de Moraes Luana Albertani Pampuch Rodolfo Moreda Mendes Harideva Marturano Egas 《International Journal of Geosciences》 CAS 2024年第7期525-548,共24页
Brazil annually faces significant challenges with mass movements, particularly in areas with poorly constructed housing, inadequate engineering, and lacking sanitation infrastructure. Campos do Jordão, in Sã... Brazil annually faces significant challenges with mass movements, particularly in areas with poorly constructed housing, inadequate engineering, and lacking sanitation infrastructure. Campos do Jordão, in São Paulo state, is a city currently grappling with these issues. This paper details a study conducted within a pilot area in Campos do Jordão, where geophysical surveys and geotechnical borehole data were integrated. The geophysical surveys provided 2D profiles, and samples were collected to analyse soil moisture and plasticity. These datasets were combined using a Cokriging-based model to produce an accurate representation of the subsurface conditions. The enhanced modelling of subsurface variability facilitates a deeper understanding of soil behavior, which can be used to improve landslide risk assessments. This approach is innovative, particularly within the international context where similar studies often do not address the complexities associated with urban planning deficits such as those observed in some areas of Brazil. These conditions, including the lack of proper sanitation and irregular housing, significantly influence the geological stability of the region, adding layers of complexity to subsurface assessments. Adapting geotechnical evaluation methods to local challenges offers the potential to increase the efficacy and relevance of geological risk management in regions with similar socio-economic and urban characteristics. 展开更多
关键词 Mass movements GEOPHYSICS ERT Geotechnical Surveys Campos do Jordão COKRIGING
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Experimental study on the movement of oil spill under freeze-thaw action
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作者 ZeLiang Ye JianGuo Lu +2 位作者 MingYi Zhang WanSheng Pei ShuTong Li 《Research in Cold and Arid Regions》 CSCD 2024年第3期111-120,共10页
Oil leakages cause environmental pollution,economic losses,and even engineering safety accidents.In cold regions,researchers urgently investigate the movement of oil spill in soils exposed to freeze-thaw cycles.In thi... Oil leakages cause environmental pollution,economic losses,and even engineering safety accidents.In cold regions,researchers urgently investigate the movement of oil spill in soils exposed to freeze-thaw cycles.In this study,a series of laboratory model experiments were carried out on the migration of oil leakage under freeze-thaw action,and the distributions of the soil temperature,unfrozen water content,and displacement were analyzed.The results showed that under freeze-thaw action,liquid water in soils migrated to the freezing front and accumulated.After the pipe cracked,oil pollutants first gathered at one side of the leak hole,and then moved around.The pipe wall temperature affected the soil temperature field,and the thermal influence range below and transverse the pipe wall(35–40 cm)was larger than that above the pipe wall(8 cm)owing to the soil surface temperature.The leaked oil's temperature would make the temperature of the surrounding soil rise.Oil would inhibit the cooling of the soils.Besides,oil migration was significantly affected by the gravity and water flow patterns.The freeze-thaw action would affect the migration of the oil,which was mainly manifested as inhibiting the diffusion and movement of oil when soils were frozen.Unfrozen water transport caused by freeze-thaw cycles would also inhibit oil migration.The research results would provide a scientific reference for understanding the relationship between the movement of oil pollutants,water,and soil temperature,and for establishing a waterheat-mass transport model in frozen soils. 展开更多
关键词 Freeze-thaw action Oil movement Soil temperature Unfrozen water content Model test
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Effect of different interventions on orthodontic tooth movement acceleration:A network meta-analysis
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作者 CHEN Hui-ying ZHANG Li +2 位作者 ZHAN Le WAN Ni MO Li-wen 《Journal of Hainan Medical University》 CAS 2024年第2期41-50,共10页
Objective: To explore the effectiveness of various interventions in accelerating tooth movement, a systematic review and net-work meta analysis were used to draw a conclusion. Methods: MEDLINE, EMBASE, Willey Library,... Objective: To explore the effectiveness of various interventions in accelerating tooth movement, a systematic review and net-work meta analysis were used to draw a conclusion. Methods: MEDLINE, EMBASE, Willey Library, EBSCO, Web of Science Databases, and Cochrane Central Register of Controlled Trials databases to identify relevant studies. ADDIS 1.16.6 and Stata 16.0 software were used for NMA. Results: Five thousand five hundred and forty-two articles were searched out. After screening by two independent investigators, forty-seven randomized controlled trials, 1 390 participants, were included in this network meta-analysis. A total of 11 interventions involving Piezocision (Piezo), Photobiomodulation therapy (PBMT), Plate- let-rich plasma(PRP), Electromagnetic field(EF), Low intensity laser therapy(LLLT), Low intensity pulsed ultrasound(LI-PUS), Low-frequency vibrations(LFV), Distraction osteogenesis(DAD), Corticotomy(Corti), Microosteoperforations (MOPS), Traditional orthodontic(OT)were identified and classified into 3 classes including surgical treatment, non-surgical treatment and traditional orthodontic treatment. According to SUCRA probability ranking of the best intervention effect, when orthodontic treatment lasted for 1 month, PBMT (90.6%), Piezo(87.4%) and MOPs(73.6%)were the top three interventions to improve the efficiency of canine tooth movement. When orthodontic treatment lasted for 2 months, Corti (75.7%), Piezo (69.6%) and LFV(58.9%)were the top three interventions for improving the mobility efficiency of canine tooth movement. When orthodontic treatment lasted for 3 months, Cort (73.3%), LLLT(68.4%)and LFV(60.8%)were the top three interventions for improving the mobility efficiency of canine tooth movement. Conclusion: PBMT and Piezo can improve the efficiency of canine tooth movement significantly after 1 month, while Corti and LFV can improve the efficiency of canine tooth movement better after 2 and 3 months. 展开更多
关键词 Orthodontic tooth movement ACCELERATION Network Meta-analysis Randomized controlled trials
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