Low Earth Orbit(LEO)satellites,with their wide coverage and large number,have gradually become a crucial platform and means for navigation and positioning services.Compared to other LEO constellations,Starlink has ove...Low Earth Orbit(LEO)satellites,with their wide coverage and large number,have gradually become a crucial platform and means for navigation and positioning services.Compared to other LEO constellations,Starlink has over 6000 satellites in orbit,and its signals contain synchronous sequences usable for pseudo-range positioning.Thus,it has a potential serve as an alternative to Global Navigation Satellite System(GNSS)for providing Positioning,Navigation,and Timing(PNT)services.Compared to parabolic antennas and electronically scanned phased array antennas for receiving Starlink signals,wide-beam antennas(such as Low-Noise Block(LNB)downconverters)can be used to achieve low-cost multi-satellite tracking.However,it also encounters the issues of distinguishing between multiple satellite signals and low received signal power,which requires high-sensitivity detection.Moreover,there are some other issues such as unknown signal transmission time and real-time satellite orbits,thereby causing failure to navigation.Accordingly,this study focuses on LEO constellations represented by Starlink,proposes a joint pseudo-range and Doppler positioning method for Starlink satellite Signals of Opportunity(SOP)based on the comprehensive utilization of signals and information from LEO satellites.Moreover,this study analyzes the signal detection capability and satellite isolation method,examines the algorithm’s orbital error suppression performance,and establishes the concept of Equivalent Position Dilution of Precision(EPDOP)S_(EPDOP)for joint pseudo-range and Doppler positioning.In the experiment because Starlink satellite signals are not available in China,we take the advantage of Iridium NEXT satellites’global seamless coverage,utilize an algorithm to get pseudo-range observations with the Iridium NEXT signals,and then combine them with Starlink Doppler observations to achieve the joint pseudo-range and Doppler positioning of LEO satellites’SOPs.The experiment results demonstrate that when relying on Starlink Doppler observations for positioning,the proposed method achieves Two-Dimensional(2D)positioning accuracy of 3.6 m and Three-Dimensional(3D)positioning accuracy of 6.2 m.Compared to existing Starlink positioning algorithms based on parabolic antennas and electronically scanned phased array antennas,this method improves the accuracy by at least 35.7%.Additionally,Iridium NEXT signals are used to validate the performance of the proposed algorithm for joint pseudo-range and Doppler positioning.In a 40 km long-baseline scenario,the algorithm achieved a 2D positioning accuracy of 24 m and a 3D positioning accuracy of 41 m with Iridium NEXT satellite pseudo-range and Doppler measurements.展开更多
Objective: To study the clinical value of positive pressure infusion joint combined with cluster nursing intervention in invasive blood pressure monitoring of critically ill patients. Methods: A total of 56 patients w...Objective: To study the clinical value of positive pressure infusion joint combined with cluster nursing intervention in invasive blood pressure monitoring of critically ill patients. Methods: A total of 56 patients who underwent invasive blood pressure monitoring from August 2020 to November 2021 were included and divided into a control group and a research group. The application effect of positive pressure infusion joint combined with cluster nursing intervention was analyzed. Results: The use of positive pressure infusion joint combined with bundle nursing measures in invasive blood pressure monitoring in patients with severe trauma had a significant effect on improving the physical and mental state of patients, and further optimized the incidence of complications (P < 0.05). Based on the development of cluster nursing measures, the emotional state of patients with severe trauma at the stage of invasive blood pressure monitoring was effectively improved, and the further implementation of related nursing content better optimized the adverse emotions of patients with anxiety and depression (P < 0.05). The development of positive pressure infusion joint combined with cluster nursing measures has important value in improving patients condition, further optimizing the efficiency of disease intervention, and promoting the improvement effect of patients physiological state (P < 0.05). Through the analysis of blood pressure and heart rate index data in the monitoring stage, the research results better confirmed that the development of positive pressure infusion joint combined with cluster nursing measures has a good value in improving patients heart rate and blood pressure indicators (P < 0.05);Cluster nursing measures combined with positive pressure infusion joint can further improve the quality of life of patients with severe blood pressure monitoring. Through the intervention of the condition and the targeted implementation of nursing quality, the quality of life score of patients is effectively optimized (P < 0.05). Discussion: In the stage of invasive blood pressure monitoring for critically ill patients, when positive pressure infusion joints are used, cluster nursing intervention measures should be jointly carried out, which can effectively guarantee the improvement of patients mood, optimize the quality of life after recovery, and improve rehabilitation efficiency, which has the value of promotion.展开更多
Background:Acute ankle injury causes damage to joint mechanoreceptors and deafferentation and contributes to proprioception deficits in patients with chronic ankle instability(CAI).We aimed to explore whether deficits...Background:Acute ankle injury causes damage to joint mechanoreceptors and deafferentation and contributes to proprioception deficits in patients with chronic ankle instability(CAI).We aimed to explore whether deficits of proprioception,including kinesthesia and joint position sense(JPS),exist in patients with CAI when compared with the uninjured contralateral side and healthy people.We hypothesized that proprioception deficits did exist in patients with CAI and that the deficits varied by test methodologies.Methods:The study was a systematic review and meta-analysis.We identified studies that compared kinesthesia or JPS in patients with CAI with the uninjured contralateral side or with healthy controls.Meta-analyses were conducted for the studies with similar test procedures,and narrative syntheses were undertaken for the rest.Results:A total of 7731 studies were identified,of which 30 were included for review.A total of 21 studies were eligible for meta-analysis.Compared with the contralateral side,patients with CAI had ankle kinesthesia deficits in inversion and plantarflexion,with a standardized mean difference(SMD)of 0.41 and 0.92,respectively,and active and passive JPS deficits in inversion(SMD=0.92 and 0.72,respectively).Compared with healthy people,patients with CAI had ankle kinesthesia deficits in inversion and eversion(SMD=0.64 and 0.76,respectively),and active JPS deficits in inversion and eversion(SMD=1.00 and 4.82,respectively).Proprioception deficits in the knee and shoulder of patients with CAI were not statistically significant.Conclusion:Proprioception,including both kinesthesia and JPS,of the injured ankle of patients with CAI was impaired,compared with the uninjured contralateral limbs and healthy people.Proprioception varied depending on different movement directions and test methodologies.The use of more detailed measurements of proprioception and interventions for restoring the deficits are recommended in the clinical management of CAI.展开更多
To control movement,the brain has to integrate proprioceptive information from a variety of mechanoreceptors.The role of proprioception in daily activities,exercise,and sports has been extensively investigated,using d...To control movement,the brain has to integrate proprioceptive information from a variety of mechanoreceptors.The role of proprioception in daily activities,exercise,and sports has been extensively investigated,using different techniques,yet the proprioceptive mechanisms underlying human movement control are still unclear.In the current work we have reviewed understanding of proprioception and the three testing methods:threshold to detection of passive motion,joint position reproduction,and active movement extent discrimination,all of which have been used for assessing proprioception.The origin of the methods,the different testing apparatus,and the procedures and protocols used in each approach are compared and discussed.Recommendations are made for choosing an appropriate technique when assessing proprioceptive mechanisms in different contexts.展开更多
基金support is received from the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA0350101)the Project(E2M4140306).
文摘Low Earth Orbit(LEO)satellites,with their wide coverage and large number,have gradually become a crucial platform and means for navigation and positioning services.Compared to other LEO constellations,Starlink has over 6000 satellites in orbit,and its signals contain synchronous sequences usable for pseudo-range positioning.Thus,it has a potential serve as an alternative to Global Navigation Satellite System(GNSS)for providing Positioning,Navigation,and Timing(PNT)services.Compared to parabolic antennas and electronically scanned phased array antennas for receiving Starlink signals,wide-beam antennas(such as Low-Noise Block(LNB)downconverters)can be used to achieve low-cost multi-satellite tracking.However,it also encounters the issues of distinguishing between multiple satellite signals and low received signal power,which requires high-sensitivity detection.Moreover,there are some other issues such as unknown signal transmission time and real-time satellite orbits,thereby causing failure to navigation.Accordingly,this study focuses on LEO constellations represented by Starlink,proposes a joint pseudo-range and Doppler positioning method for Starlink satellite Signals of Opportunity(SOP)based on the comprehensive utilization of signals and information from LEO satellites.Moreover,this study analyzes the signal detection capability and satellite isolation method,examines the algorithm’s orbital error suppression performance,and establishes the concept of Equivalent Position Dilution of Precision(EPDOP)S_(EPDOP)for joint pseudo-range and Doppler positioning.In the experiment because Starlink satellite signals are not available in China,we take the advantage of Iridium NEXT satellites’global seamless coverage,utilize an algorithm to get pseudo-range observations with the Iridium NEXT signals,and then combine them with Starlink Doppler observations to achieve the joint pseudo-range and Doppler positioning of LEO satellites’SOPs.The experiment results demonstrate that when relying on Starlink Doppler observations for positioning,the proposed method achieves Two-Dimensional(2D)positioning accuracy of 3.6 m and Three-Dimensional(3D)positioning accuracy of 6.2 m.Compared to existing Starlink positioning algorithms based on parabolic antennas and electronically scanned phased array antennas,this method improves the accuracy by at least 35.7%.Additionally,Iridium NEXT signals are used to validate the performance of the proposed algorithm for joint pseudo-range and Doppler positioning.In a 40 km long-baseline scenario,the algorithm achieved a 2D positioning accuracy of 24 m and a 3D positioning accuracy of 41 m with Iridium NEXT satellite pseudo-range and Doppler measurements.
文摘Objective: To study the clinical value of positive pressure infusion joint combined with cluster nursing intervention in invasive blood pressure monitoring of critically ill patients. Methods: A total of 56 patients who underwent invasive blood pressure monitoring from August 2020 to November 2021 were included and divided into a control group and a research group. The application effect of positive pressure infusion joint combined with cluster nursing intervention was analyzed. Results: The use of positive pressure infusion joint combined with bundle nursing measures in invasive blood pressure monitoring in patients with severe trauma had a significant effect on improving the physical and mental state of patients, and further optimized the incidence of complications (P < 0.05). Based on the development of cluster nursing measures, the emotional state of patients with severe trauma at the stage of invasive blood pressure monitoring was effectively improved, and the further implementation of related nursing content better optimized the adverse emotions of patients with anxiety and depression (P < 0.05). The development of positive pressure infusion joint combined with cluster nursing measures has important value in improving patients condition, further optimizing the efficiency of disease intervention, and promoting the improvement effect of patients physiological state (P < 0.05). Through the analysis of blood pressure and heart rate index data in the monitoring stage, the research results better confirmed that the development of positive pressure infusion joint combined with cluster nursing measures has a good value in improving patients heart rate and blood pressure indicators (P < 0.05);Cluster nursing measures combined with positive pressure infusion joint can further improve the quality of life of patients with severe blood pressure monitoring. Through the intervention of the condition and the targeted implementation of nursing quality, the quality of life score of patients is effectively optimized (P < 0.05). Discussion: In the stage of invasive blood pressure monitoring for critically ill patients, when positive pressure infusion joints are used, cluster nursing intervention measures should be jointly carried out, which can effectively guarantee the improvement of patients mood, optimize the quality of life after recovery, and improve rehabilitation efficiency, which has the value of promotion.
基金the National Natural Science Foundation of China(Grant No.81871823).
文摘Background:Acute ankle injury causes damage to joint mechanoreceptors and deafferentation and contributes to proprioception deficits in patients with chronic ankle instability(CAI).We aimed to explore whether deficits of proprioception,including kinesthesia and joint position sense(JPS),exist in patients with CAI when compared with the uninjured contralateral side and healthy people.We hypothesized that proprioception deficits did exist in patients with CAI and that the deficits varied by test methodologies.Methods:The study was a systematic review and meta-analysis.We identified studies that compared kinesthesia or JPS in patients with CAI with the uninjured contralateral side or with healthy controls.Meta-analyses were conducted for the studies with similar test procedures,and narrative syntheses were undertaken for the rest.Results:A total of 7731 studies were identified,of which 30 were included for review.A total of 21 studies were eligible for meta-analysis.Compared with the contralateral side,patients with CAI had ankle kinesthesia deficits in inversion and plantarflexion,with a standardized mean difference(SMD)of 0.41 and 0.92,respectively,and active and passive JPS deficits in inversion(SMD=0.92 and 0.72,respectively).Compared with healthy people,patients with CAI had ankle kinesthesia deficits in inversion and eversion(SMD=0.64 and 0.76,respectively),and active JPS deficits in inversion and eversion(SMD=1.00 and 4.82,respectively).Proprioception deficits in the knee and shoulder of patients with CAI were not statistically significant.Conclusion:Proprioception,including both kinesthesia and JPS,of the injured ankle of patients with CAI was impaired,compared with the uninjured contralateral limbs and healthy people.Proprioception varied depending on different movement directions and test methodologies.The use of more detailed measurements of proprioception and interventions for restoring the deficits are recommended in the clinical management of CAI.
基金the University of Canberra,Key Laboratory of Exercise and Health Sciences of Ministry of Education,Shanghai University of Sport and Shanghai Municipal Science and Technology Commission (No.13490503800)supported by Shanghai Pujiang Program (No.15PJ1407600)
文摘To control movement,the brain has to integrate proprioceptive information from a variety of mechanoreceptors.The role of proprioception in daily activities,exercise,and sports has been extensively investigated,using different techniques,yet the proprioceptive mechanisms underlying human movement control are still unclear.In the current work we have reviewed understanding of proprioception and the three testing methods:threshold to detection of passive motion,joint position reproduction,and active movement extent discrimination,all of which have been used for assessing proprioception.The origin of the methods,the different testing apparatus,and the procedures and protocols used in each approach are compared and discussed.Recommendations are made for choosing an appropriate technique when assessing proprioceptive mechanisms in different contexts.
