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Intraoperative Blood Pressure Lability Acts as a Key Mediator in the Impacts of Goal-Directed Fluid Therapy on Postoperative Complications in Patients Undergoing Major Spine Surgery
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作者 Lu Che Jia-Wen Yu +2 位作者 Yue-Lun Zhang Li Xu Yu-Guang Huang 《Chinese Medical Sciences Journal》 CAS CSCD 2023年第4期257-264,共8页
Objective Although goal-directed fluid therapy(GDFT)has been proven to be effective in reducing the incidence of postoperative complications,the underlying mechanisms remain unknown.The aim of this study was to examin... Objective Although goal-directed fluid therapy(GDFT)has been proven to be effective in reducing the incidence of postoperative complications,the underlying mechanisms remain unknown.The aim of this study was to examine the mediating role of intraoperative hemodynamic lability in the association between GDFT and the incidence of postoperative complications.We further tested the role of this mediation effect using mean arterial pressure,a hemodynamic indicator.Methods This secondary analysis used the dataset of a completed nonrandomized controlled study to investigate the effect of GDFT on the incidence of postoperative complications in patients undergoing posterior spine arthrodesis.We used a simple mediation model to test whether there was a mediation effect of average real variability between the association of GDFT and postoperative complications.We conducted mediation analysis using the mediation package in R(version 3.1.2),based on 5,000 bootstrapped samples,adjusting for covariates.Results Among the 300 patients in the study,40%(120/300)developed postoperative complications within 30 days.GDFT was associated with fewer 30-day postoperative complications after adjustment for confounders(odds ratio:0.460,95%CI:0.278,0.761;P=0.003).The total effect of GDFT on postoperative complications was-0.18(95%CI:-0.28,-0.07;P<0.01).The average causal mediation effect was-0.08(95%CI:-0.15,-0.04;P<0.01).The average direct effect was-0.09(95%CI:-0.20,0.03;P=0.17).The proportion mediated was 49.9%(95%CI:18.3%,140.0%).Conclusions The intraoperative blood pressure lability mediates the relationship between GDFT and the incidence of postoperative complications.Future research is needed to clarify whether actively reducing intraoperative blood pressure lability can prevent postoperative complications. 展开更多
关键词 goal-directed fluid therapy mediation analysis postoperative complications hemodynamic stability
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Extension of Goal-Directed Behavior Model for Post-Pandemic Korean Travel Intentions to Alternative Local Destinations: Perceived Risk and Knowledge
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作者 Heesup Han Hong Ngoc Nguyen +1 位作者 Hyerin Lee Sanghyeop Lee 《International Journal of Mental Health Promotion》 2023年第4期449-469,共21页
Since the outbreak of COVID-19,tourists have been increasingly concerned over various risks of international travel,while knowledge of the pandemic appears to vary significantly.In addition,as travel restrictions cont... Since the outbreak of COVID-19,tourists have been increasingly concerned over various risks of international travel,while knowledge of the pandemic appears to vary significantly.In addition,as travel restrictions continue to impact adversely on international tourism,tourism efforts should be placed more on the domestic markets.Via structural equation modeling,this study unearthed different risk factors impacting Korean travelers’choices of alternative local destinations in the post-pandemic era.In addition,this study extended the goal-directed behavior framework with the acquisition of perceived risk and knowledge of COVID-19,which was proven to hold a sig-nificantly superior explanatory power of tourists’decisions of local alternatives over foreign countries during the COVID-19 pandemic.Furthermore,desire was found to play an imminent mediating role in the conceptual mod-el,maximizing the impact of perceived risk on travel intentions.Henceforth,this research offers meaningful the-oretical implication as thefirst empirical study to deepen the goal-directed behaviour framework with perceived risk and knowledge in the context of post-COVID-19 era.It also serves as insightful knowledge for Korean tour-ism authorities and practitioners to understand local tourists’decision-making processes and tailor effective recovery strategy for domestic tourism. 展开更多
关键词 Travel intention goal-directed behavior desire perceived risk COVID-19 domestic tourism Korean tourists
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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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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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Obtaining 2D Soil Resistance Profiles from the Integration of Electrical Resistivity Data and Standard Penetration Test (SPT) and Light Dynamic Penetrometer (DPL) Resistance Tests—Applications in Mass Movements Studies
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作者 Cassiano Antonio Bortolozo Tatiana Sussel Gonçalves Mendes +10 位作者 Mariana Ferreira Benessiuti Motta Silvio Jorge Coelho Simões Tristan Pryer Daniel Metodiev Marcio Roberto Magalhães de Andrade Maiconn Vinicius de Moraes Danielle Silva de Paula Nélio José Bastos Luana Albertani Pampuch Rodolfo Moreda Mendes Marcio Augusto Ernesto de Moraes 《International Journal of Geosciences》 2023年第9期840-854,共15页
In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occ... In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occurrences. The multifaceted nature of these influences makes the surveillance of mass movements a highly intricate task, requiring an understanding of numerous interdependent variables. Recent years have seen an emergence in scholarly research aimed at integrating geophysical and geotechnical methodologies. The conjoint examination of geophysical and geotechnical data offers an enhanced perspective into subsurface structures. Within this work, a methodology is proposed for the synchronous analysis of electrical resistivity geophysical data and geotechnical data, specifically those extracted from the Light Dynamic Penetrometer (DPL) and Standard Penetration Test (SPT). This study involved a linear fitting process to correlate resistivity with N10/SPT N-values from DPL/SPT soundings, culminating in a 2D profile of N10/SPT N-values predicated on electrical profiles. The findings of this research furnish invaluable insights into slope stability by allowing for a two-dimensional representation of penetration resistance properties. Through the synthesis of geophysical and geotechnical data, this project aims to augment the comprehension of subsurface conditions, with potential implications for refining landslide risk evaluations. This endeavor offers insight into the formulation of more effective and precise slope management protocols and disaster prevention strategies. 展开更多
关键词 GEOPHYSICS Geotechnical Data Electrical Resistivity Method Standard Penetration Test (SPT) Light Dynamic Penetrometer (DPL) Mass movements
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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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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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Movement Function Assessment Based on Human Pose Estimation from Multi-View
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作者 Lingling Chen Tong Liu +1 位作者 Zhuo Gong Ding Wang 《Computer Systems Science & Engineering》 2024年第2期321-339,共19页
Human pose estimation is a basic and critical task in the field of computer vision that involves determining the position(or spatial coordinates)of the joints of the human body in a given image or video.It is widely u... Human pose estimation is a basic and critical task in the field of computer vision that involves determining the position(or spatial coordinates)of the joints of the human body in a given image or video.It is widely used in motion analysis,medical evaluation,and behavior monitoring.In this paper,the authors propose a method for multi-view human pose estimation.Two image sensors were placed orthogonally with respect to each other to capture the pose of the subject as they moved,and this yielded accurate and comprehensive results of three-dimensional(3D)motion reconstruction that helped capture their multi-directional poses.Following this,we propose a method based on 3D pose estimation to assess the similarity of the features of motion of patients with motor dysfunction by comparing differences between their range of motion and that of normal subjects.We converted these differences into Fugl–Meyer assessment(FMA)scores in order to quantify them.Finally,we implemented the proposed method in the Unity framework,and built a Virtual Reality platform that provides users with human–computer interaction to make the task more enjoyable for them and ensure their active participation in the assessment process.The goal is to provide a suitable means of assessing movement disorders without requiring the immediate supervision of a physician. 展开更多
关键词 Human pose estimation 3D pose reconstruction assessment of movement function plane of features of human motion
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Muscle Strength, Lumbar Curve, Fear of Movement and Functional Disability among Patients with Lumbar Disc Herniation: A Review
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作者 G. M. Jakaria Chua Siew Kuan 《Open Journal of Therapy and Rehabilitation》 2024年第1期28-51,共24页
Introduction: Lumbar disc herniation (LDH) refers to the rupture of the fibrous annulus of the intervertebral discs. Lumbar curvature may lead to the occurrence of lumbar disc degeneration. Fear of movement may worsen... Introduction: Lumbar disc herniation (LDH) refers to the rupture of the fibrous annulus of the intervertebral discs. Lumbar curvature may lead to the occurrence of lumbar disc degeneration. Fear of movement may worsen their disc herniation and cause further pain and injury. LDH conditions impact the individuals’ quality of life, to explore the relationship between lumbar curve, muscle strength, fear of movement and functional disability among patients with LDH. Methods: An electronic search was conducted on PubMed, Medline, Science Direct, Springerlink, Google Scholar and a hand search from reference lists was reviewed. Publications were included in human studies, patients 25 - 85 years of age, original studies and published in English language journals from January 2002 to December 2023. Result: In total, 64 articles were researched through the online search engines, and 9 papers were found through manual searches of reference lists. As a result, a total of 11 articles were included for the purpose of this review. The comprehensive analysis revealed the presence of eight cross-sectional studies, two retrospective studies and one experimental study. A minimum of 25 participants and a maximum of 360 participants were included. Ten studies included both genders, only one studies included healthy adults and patients with LDH but these studies didn’t mention gender. Results showed that the factors influencing LDH can be categorized into non-modifiable factors, such as gender, age, height or others. Modifiable factors included increased BMI, DM, smoking, alcohol, employment status, lifestyle and health problems or psychology. Conclusion: Females with greater VASC may be at risk of LDH. The lumbar extensor muscles indicated a localized disc herniation or nerve root pathology in patients with LDH. The fear of movement may lead to psychological consequences and reduce functional disability among patients with LDH. 展开更多
关键词 Lumbar Disc Herniation Fear of movement Functional Disability Vertical Angle of Spinal Curvature
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Research progress of 24-hour movement behaviors in chronic non-communicable disease
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作者 Rong-Xuan Li Qing-Qing Fan Di Cui 《Life Research》 2024年第3期24-34,共11页
Chronic non-communicable diseases(NCDs)represent a significant impediment to improve life expectancy and remain a focal point in global public health and disease prevention efforts.24-hour movement behaviors,which inc... Chronic non-communicable diseases(NCDs)represent a significant impediment to improve life expectancy and remain a focal point in global public health and disease prevention efforts.24-hour movement behaviors,which include sleep,sedentary behavior(SED),and physical activity,underscore the inherent connections between different daily activities and the comprehensive impact of overall movement patterns on health.Evidence suggested that modifying patterns of 24-hour movement behaviors can aid in preventing and attenuating the progression of NCDs.This study systematically delineated the concept,evolution,analytical methods,and intrinsic associations of 24-hour movement behaviors,emphasizing their pivotal role in the prevention and management of NCDs such as obesity,mental disorders,cardiovascular diseases,diabetes,and renal diseases.Future research endeavors should focus on refining methodologies,broadening study populations,developing research tools,and exploring precise intervention strategies and interdisciplinary approaches to comprehensively enhance the effectiveness of NCDs prevention and management from a temporal perspective.Such efforts are poised to provide substantive guidance and support for public health practices. 展开更多
关键词 chronic non-communicable diseases 24-hour movement behaviors time-use epidemiology isotemporal substitution model compositional data analysis
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“Eternal Motion” as a “Form of Movement of a Special Nature” and the Main Condition for the Creation of the Universe
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作者 Avas Khugaev Eugeniya Bibaeva 《Journal of Applied Mathematics and Physics》 2024年第6期2041-2068,共28页
The article hypothesizes that DE and DM (UCM) are a “Form of Motion of a Special Nature”, where “Form of Motion” means “Eternal Motion” as the power of dynamics of different levels and varying degrees of self-su... The article hypothesizes that DE and DM (UCM) are a “Form of Motion of a Special Nature”, where “Form of Motion” means “Eternal Motion” as the power of dynamics of different levels and varying degrees of self-sufficiency, and by “Special Nature”, gravitational and two other properties of matter, “tied” to the “Eternal Movement” and completely dependent on it. Carriers of key properties of a “Special Nature” have been established: “0”-DE particles and “3”-DM particles (UDM). The unity of their inherent “motionally-gravitational” properties and the peculiarity of the relationship between “motion” and “gravity” are revealed: the higher the intensity of “Eternal Motion”, the stronger the gravitational properties of matter are manifested (and vice versa). The relationship of “time” with the “vibration frequency” and the “mass” of photons with the “degree of bonding and deformation properties of the field” is shown. The maximum level of gravity has been determined, which allows Nature to successfully create the Universe: such a landmark is the proximity to the property of the Primary Source—the “pure graviton” of the OSP space, the most powerful “motionally-gravitational” particle of the Universe. The reasons for the emergence of such an identity of the gravitational properties of particles with the indicators of a “pure graviton” are established: for “0”-DE particles, this is the acquisition of the function of “freedom of movement”;for “3”-DM particles (UDM), the creation of a special structure—a “double field” (“Main” and “Small”). The presence in the “double field” of specific “tools” for the creation of the worlds of the Universe—gravitational “waves” gives rise to impulses (shocks) of varying intensity and shape. A list of functions performed by “waves” in the “Main” and “Small” fields has been compiled. The specific conditions for the formation of “UDM Streams”, their transformation into a “Vortex” and, under the influence of a powerful Initial Impulse (push), sending them to the “place” of the creation of galaxies, are shown. It is suggested that there is a “Cycle of Matter in Nature” in the closed structure of our Universe due to the “work” of “waves” and the functioning of special “factories” in the form of exotic space objects—Black holes. 展开更多
关键词 DE DM (UCM) Graviton Eternal motion Double Field of the Universe Motionally-Gravitational Particles Degree of Self-Sufficiency Main Field Small Field Gravitational Waves Primary Impulse Flows UDM Vortex Time Massive Photons Clumps of DM movement of Galaxies Factories of Black Holes Circulation of Matter in Nature
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Far-field crustal movements before and after the 2011 Ms9.0 Japan earthquake from GPS observations 被引量:14
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作者 Gu Guohua Wang Wuxing 《Geodesy and Geodynamics》 2011年第3期1-7,共7页
关键词 Japan earthquake crustal movement GPS earthquake prediction co-seismic displacement
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Using Quantile Regression Approach to Analyze Price Movements of Agricultural Products in China 被引量:7
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作者 LI Gan-qiong XU Shi-wei +2 位作者 LI Zhe-min SUN Yi-guo DONG Xiao-xia 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第4期674-683,共10页
This paper studies how the price movements of pork,chicken and egg respond to those of related cost factors in short terms in Chinese market.We employ a linear quantile approach not only to explore potential data hete... This paper studies how the price movements of pork,chicken and egg respond to those of related cost factors in short terms in Chinese market.We employ a linear quantile approach not only to explore potential data heteroscedasticity but also to generate confidence bands for the purpose of price stability study.We then evaluate our models by comparing the prediction intervals generated from the quantile regression models with in-sample and out-of-sample forecasts.Using monthly data from January 2000 to October 2010,we observed these findings:(i) the price changes of cost factors asymmetrically and unequally influence those of the livestock across different quantiles;(ii) the performance of our models is robust and consistent for both in-sample and out-of-sample forecasts;(iii) the confidence intervals generated from 0.05th and 0.95th quantile regression models are good methods to forecast livestock price fluctuation. 展开更多
关键词 cost factors agricultural products forecasting price movements quantile regression model
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Eye Movements, Cognitive Processes, and Reading 被引量:6
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作者 Keith Rayner 《心理与行为研究》 2004年第3期482-488,共7页
关键词 eye movements perceptual SPAN INTEGRATION ACROSS SACCADES eye movement control.
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Goal-directed therapy in intraoperative fluid and hemodynamic management 被引量:7
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作者 Maria Cristina Gutierrez Peter G.Moore Hong Liu 《The Journal of Biomedical Research》 CAS 2013年第5期357-365,共9页
Intraoperative fluid management is pivotal to the outcome and success of surgery, especially in high-risk proce- dures. Empirical formula and invasive static monitoring have been traditionally used to guide intraopera... Intraoperative fluid management is pivotal to the outcome and success of surgery, especially in high-risk proce- dures. Empirical formula and invasive static monitoring have been traditionally used to guide intraoperative fluid management and assess volume status. With the awareness of the potential complications of invasive procedures and the poor reliability of these methods as indicators of volume status, we present a case scenario of a patient who underwent major abdominal surgery as an example to discuss how the use of minimally invasive dynamic monitoring may guide intraoperative fluid therapy. 展开更多
关键词 high-risk surgery HEMODYNAMIC FLUID monitoring goal-directed therapy
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Anomalous crustal movements before great Wenchuan earthquake observed by GPS 被引量:10
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作者 Gu Guohua Meng Guojie Wang Wuxing 《Geodesy and Geodynamics》 2011年第2期13-22,共10页
Studies of GPS data carried out before and after the great Wenchuan earthquake of Ms8.0 on May 12, 2008 show that anomalous crustal movements occurred before the earthquake. Data from 4 pre-earthquake observation sess... Studies of GPS data carried out before and after the great Wenchuan earthquake of Ms8.0 on May 12, 2008 show that anomalous crustal movements occurred before the earthquake. Data from 4 pre-earthquake observation sessions at a dense network of stations show that there were prominent broad-ranged long- and midterm anomalies in horizontal displacements and strain and in vertical displacements. Data from the fewer-numbered reference stations of continuous GPS observations since 1999 in West and South China showed short-term preseismic anomalies in horizontal displacements. The detection of co-seismic horizontal displacements at these stations supports the existence of the pre-earthquake anomalies. Results of single-epoch solutions of data from continuous-observation stations near the epicenter also show large imminent anomalies in vertical displacements. Although the Wenchuan earthquake was not predicted, these results give a strong indication that GPS should be the main observation technique for long-term, mid-term, short-term and imminent earthquake predictions. 展开更多
关键词 Wenchuan earthquake earthquake prediction GPS crustal movement horizontal displace- ment vertical displacement
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Energy-optimal control model for train movements 被引量:3
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作者 李克平 高自友 毛保华 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第2期359-364,共6页
In this paper, we propose a new cellular automaton (CA) model for train movement simulations under mixed traffic conditions. A kind of control strategy is employed for trains to reduce energy consumption. In the pro... In this paper, we propose a new cellular automaton (CA) model for train movement simulations under mixed traffic conditions. A kind of control strategy is employed for trains to reduce energy consumption. In the proposed CA model, the driver controls the train movements by using some updated rules. In order to obtain a good insight into the evolution behaviours of the rail traffic flow, we investigate the space-time diagram of the rail traffic flow and the trajectories of the train movements. The numerical simulation results demonstrate that the proposed CA model can well describe the dynamic behaviours of the train movements. Some complex phenomena of train movements can be reproduced, such as the train delay propagations, etc. 展开更多
关键词 train movement cellular automaton moving-block
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Earth crust vertical movements according to ITRF2000, ITRF2005,ITRF2008 and ITRF2014 coordinate systems and their comparing analysis 被引量:3
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作者 N.A.Chujkova T.G.Maximova +1 位作者 T.S.Chesnokova A.N.Grushinsky 《Geodesy and Geodynamics》 2018年第2期109-114,共6页
The analysis of Earth’s crust movement vertical velocities was made both for separate regions, and averaged on regions. As input data coordinates and velocities of earth crust points, obtained in International Coordi... The analysis of Earth’s crust movement vertical velocities was made both for separate regions, and averaged on regions. As input data coordinates and velocities of earth crust points, obtained in International Coordinate Systems ITRF2000, ITRF2005,ITRF2008 on the base of processing radio interferometric(VLBI), laser(SLR), Doppler(DORIS) and GPS observations was used. For the purpose of global analysis all input velocity values were averaged in the x trapezoids. For filling trapezoids the spherical function expansion to N=36 was made. Expansion harmonic coefficients allowed determine the global characteristics of earth crust movements both for all Earth, and for separate hemispheres, polar and equatorial regions, continents and oceans. It appears, that polar regions were risen, and equatorial ones were lowered, that can indicate the modern Earth oblateness reduction. The constructed maps of vertical velocities were compared with obtained by us map of earth crust strain distribution. It is appeared, that regions of modern earth surface rising(Fennoscandia, Canada, Antarctica) coincide with regions of vertical extension strain, and the lowering regions-with compression regions. Simultaneously with the determination of harmonious coefficients the mean-square error of approximation for expansion of power n=1 N and power dispersion were determined. Whereas the results converge badly and dispersion increased with the n grows, hence we can concludes, that vertical movements do not characterized global earth crust movement and denotes the unrelated character of these movement. Seemingly, the main cause of such movement origin is the local seismic events(earthquake, volcanic eruption and so on). It confirms by our conclusions about correspondence of vertical strain maximal gradient(and therefore vertical velocities) map of the earthquake distribution. In work the detailed analysis of obtained results for separate Earth’s regions was made. 展开更多
关键词 Crust movement Coordinate system UPLIFT
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Mass movements in small canyons in the northeast of Baiyun deepwater area, north of the South China Sea 被引量:4
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作者 LI Xishuang LIU Lejun +3 位作者 LI Jiagang GAO Shan ZHOU Qingjie SU Tianyun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第8期35-42,共8页
The process of mass movements and their consequent turbidity currents in large submarine canyons has been widely reported, however, little attention was paid to that in small canyons. In this paper, we document mass m... The process of mass movements and their consequent turbidity currents in large submarine canyons has been widely reported, however, little attention was paid to that in small canyons. In this paper, we document mass movements in small submarine canyons in the northeast of Baiyun deepwater area, north of the South China Sea (SCS), and their strong effects on the evolution of the canyons based on geophysical data. Submarine canyons in the study area arrange closely below the shelf break zone which was at the depth of -500 m. Within submarine canyons, seabed surface was covered with amounts of failure scars resulted from past small-sized landslides. A complex process of mass transportation in the canyons is indicated by three directions of mass movements. Recent mass movement deposits in the canyons exhibit translucent reflections or parallel reflections which represent the brittle deformation and the plastic deformation, respectively. The area of most landslides in the canyons is less than 3 km2. The trigger mechanisms for mass movements in the study area are gravitational overloading, slope angle and weak properties of soil. Geophysical data indicate that the genesis of submarine canyons is the erosion of mass movements and consequent turbidity currents. The significant effects of mass movements on canyon are incision and sediment transportation at the erosion phases and fillings supply at the fill phases. This research will be helpful for the geological risk assessments and understanding the sediment transportation in the northern margin of the SCS. 展开更多
关键词 mass movement geophysical data trigger mechanism submarine canyon north of the South China Sea
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Observations of coastal aeolian dune movements at Feicuidao, on the Changli Gold Coast in Hebei Province 被引量:3
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作者 YuXiang Dong DeQuan Huang JianHui Du 《Research in Cold and Arid Regions》 CSCD 2013年第3期324-330,共7页
High-precision RTK GPS technology was used to survey the movements of typical coastal dunes, including a coastal crescent dune and a coastal transverse ridge, in the Feicuidao region of the Changli Gold Coast in Hebei... High-precision RTK GPS technology was used to survey the movements of typical coastal dunes, including a coastal crescent dune and a coastal transverse ridge, in the Feicuidao region of the Changli Gold Coast in Hebei Province in 2006-2008. Our data provide information on the direction, type, and velocity of coastal dune movements, and indicate that the coastal dunes in this re- gion are characterized as slow and landward advancing, with to-and-fro fluctuations. The bottom of the studied coastal transverse ridge was stable during the observation period but the position of its crest advanced eastward (seaward) during summer and au- tumn, and moved landward (westward) in winter and spring. Thus, its crest moved generally landward (westward) but fluctuated to-and-fro eastward and westward. In contrast, the entire coastal crescent dune advanced landward (westward) in a to-and-fro manner, and the velocity of its movement was faster than that of the transverse ridge dune. These results are mainly related to the wind conditions in the research area, the height and volume of the two types of coastal dunes. 展开更多
关键词 coastal dune movement observation Changli in Hebei Province
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