Nowadays,there is still a need for the development of a high-precision measurement system for aircraft structural elements vibrations,this is due to the fact that many aviation problems are associated with analyzing v...Nowadays,there is still a need for the development of a high-precision measurement system for aircraft structural elements vibrations,this is due to the fact that many aviation problems are associated with analyzing vibration characteristics of aircraft mechanical structures during its main modes of operation,including flight,particularly the airplane wing health monitoring.This paper presents preliminary results of research carried out toward building a promising system designed to measure vibration parameters of airplane wing.Comparing it with the existing analogues systems,the proposed system features the use of approaches that are traditional for solving orientation and navigation problems for vibration measurements.The article discusses the principles of building such system based on micromechanical inertialmeasurements units,displacement sensors,on-board aircraft navigation system and sensor data fusion technology.The paper provides a brief overview of the existing solutions in this field of research,and substantiates the relevance and feasibility of the proposed technical solution.The paper presents the basic hardware components of the proposed system,presents the fundamentals of its operation based on the data collected frommany sources,including displacement sensors,inertial units and the optimal Kalman estimation and correction algorithm.Besides,the paper presents the mathematical errors models of the system main components.The main algorithms of the system are shown,including algorithms for inertial measurements,estimation and correction in a closed-loop scheme for including optimal Kalman filter,and indirect calculations of vibration parameters.Finally,the initial simulation results of system operation are shown,demonstrating its operability and expected accuracy characteristics,which confirms the system effectiveness and the prospects of the chosen direction of research.展开更多
BACKGROUND Diabetes is a serious public health concern in China,with 30%of patients developing retinopathy,and diabetic macular edema(DME)having the biggest impact on vision.High blood glucose level can cause retinal ...BACKGROUND Diabetes is a serious public health concern in China,with 30%of patients developing retinopathy,and diabetic macular edema(DME)having the biggest impact on vision.High blood glucose level can cause retinal cell hypoxia,thus promoting vascular endothelial growth factor(VEGF)formation and increasing vascular permeability,which induces DME.Moreover,cell hypoxia can accelerate the rate of apoptosis,which leads to the aging of patients.In severe cases,optic cell apoptosis or retinal fibrosis and permanent blindness may occur.AIM To investigate and compare the efficacy,mechanism,and differences between two anti-VEGF drugs(Compaq and ranibizumab)in DME patients.METHODS Ninety-six patients with DME who attended our hospital from April 2018 to February 2020 were included and randomly divided into two groups(Compaq group and ranibizumab group).The groups received vitreal cavity injections of 0.5 mg Compaq and 0.5 mg ranibizumab,respectively,once a month.The best corrected visual acuity(BCVA),intraocular pressure(IOP),macular retinal thickness(CMT),macular choroidal thickness(SFCT),foveal no perfusion area(FAZ),superficial capillary density,deep capillary density,treatment effect,and adverse reactions were compared before and after treatment and between the two groups.RESULTS Before treatment and 1-mo post-treatment,there was no statistically significant difference in the estimated BCVA in both groups(P>0.05).BCVA decreased in the Compaq group 3 mo after treatment,and the difference was statistically significant(P<0.05).Before treatment,and 1 mo and 3 mo post-treatment,there was no statistically significant difference in the estimated IOP in either group(P>0.05).Before treatment and 1-mo post-treatment,there was no statistically significant difference in the estimated CMT,SFCT,or FAZ in either group(P>0.05).CMT and SFCT values decreased in the Compaq group 3 mo post-treatment,and the difference was statistically significant(P<0.05).Before treatment,and 1 mo and 3 mo post-treatment,there were no statistically significant differences in vascular density in the shallow or deep capillary plexi of the fovea,parafovea,or overall macular area between the two groups(P>0.05).Marked efficient,effective,and invalid rates were 70.83%and 52.08%,27.08%and 39.58%,and 2.08%and 8.33%in the Compaq and ranibizumab groups,respectively.The differences between the two groups were statistically significant(P<0.05).CONCLUSION Anti-VEGF drugs can effectively improve CMT and SFCT,without affecting microcirculation,thus providing an effective and safe treatment for patients with DME.展开更多
This work proposes a method to concurrently calibrate multiple acoustic speeds in different mediums with a photoacoustic（PA） and ultrasound（US） dual-modality imaging system. First, physical infrastructure informat...This work proposes a method to concurrently calibrate multiple acoustic speeds in different mediums with a photoacoustic（PA） and ultrasound（US） dual-modality imaging system. First, physical infrastructure information of the target is acquired through a US image. Then, we repeatedly build PA images around a special target to yield the best focused result by dynamically updating the acoustic speeds in a different medium of the target.With these correct acoustic propagation velocities in the according mediums, we can effectively optimize the PA image quality as the experiments proved, which might benefit future research in biomedical imaging science.展开更多
文摘Nowadays,there is still a need for the development of a high-precision measurement system for aircraft structural elements vibrations,this is due to the fact that many aviation problems are associated with analyzing vibration characteristics of aircraft mechanical structures during its main modes of operation,including flight,particularly the airplane wing health monitoring.This paper presents preliminary results of research carried out toward building a promising system designed to measure vibration parameters of airplane wing.Comparing it with the existing analogues systems,the proposed system features the use of approaches that are traditional for solving orientation and navigation problems for vibration measurements.The article discusses the principles of building such system based on micromechanical inertialmeasurements units,displacement sensors,on-board aircraft navigation system and sensor data fusion technology.The paper provides a brief overview of the existing solutions in this field of research,and substantiates the relevance and feasibility of the proposed technical solution.The paper presents the basic hardware components of the proposed system,presents the fundamentals of its operation based on the data collected frommany sources,including displacement sensors,inertial units and the optimal Kalman estimation and correction algorithm.Besides,the paper presents the mathematical errors models of the system main components.The main algorithms of the system are shown,including algorithms for inertial measurements,estimation and correction in a closed-loop scheme for including optimal Kalman filter,and indirect calculations of vibration parameters.Finally,the initial simulation results of system operation are shown,demonstrating its operability and expected accuracy characteristics,which confirms the system effectiveness and the prospects of the chosen direction of research.
文摘BACKGROUND Diabetes is a serious public health concern in China,with 30%of patients developing retinopathy,and diabetic macular edema(DME)having the biggest impact on vision.High blood glucose level can cause retinal cell hypoxia,thus promoting vascular endothelial growth factor(VEGF)formation and increasing vascular permeability,which induces DME.Moreover,cell hypoxia can accelerate the rate of apoptosis,which leads to the aging of patients.In severe cases,optic cell apoptosis or retinal fibrosis and permanent blindness may occur.AIM To investigate and compare the efficacy,mechanism,and differences between two anti-VEGF drugs(Compaq and ranibizumab)in DME patients.METHODS Ninety-six patients with DME who attended our hospital from April 2018 to February 2020 were included and randomly divided into two groups(Compaq group and ranibizumab group).The groups received vitreal cavity injections of 0.5 mg Compaq and 0.5 mg ranibizumab,respectively,once a month.The best corrected visual acuity(BCVA),intraocular pressure(IOP),macular retinal thickness(CMT),macular choroidal thickness(SFCT),foveal no perfusion area(FAZ),superficial capillary density,deep capillary density,treatment effect,and adverse reactions were compared before and after treatment and between the two groups.RESULTS Before treatment and 1-mo post-treatment,there was no statistically significant difference in the estimated BCVA in both groups(P>0.05).BCVA decreased in the Compaq group 3 mo after treatment,and the difference was statistically significant(P<0.05).Before treatment,and 1 mo and 3 mo post-treatment,there was no statistically significant difference in the estimated IOP in either group(P>0.05).Before treatment and 1-mo post-treatment,there was no statistically significant difference in the estimated CMT,SFCT,or FAZ in either group(P>0.05).CMT and SFCT values decreased in the Compaq group 3 mo post-treatment,and the difference was statistically significant(P<0.05).Before treatment,and 1 mo and 3 mo post-treatment,there were no statistically significant differences in vascular density in the shallow or deep capillary plexi of the fovea,parafovea,or overall macular area between the two groups(P>0.05).Marked efficient,effective,and invalid rates were 70.83%and 52.08%,27.08%and 39.58%,and 2.08%and 8.33%in the Compaq and ranibizumab groups,respectively.The differences between the two groups were statistically significant(P<0.05).CONCLUSION Anti-VEGF drugs can effectively improve CMT and SFCT,without affecting microcirculation,thus providing an effective and safe treatment for patients with DME.
基金supported by National Natural Science Foundation of China(No.61201425)the Natural Science Foundation of Jiangsu Province(No.BK20131280)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘This work proposes a method to concurrently calibrate multiple acoustic speeds in different mediums with a photoacoustic（PA） and ultrasound（US） dual-modality imaging system. First, physical infrastructure information of the target is acquired through a US image. Then, we repeatedly build PA images around a special target to yield the best focused result by dynamically updating the acoustic speeds in a different medium of the target.With these correct acoustic propagation velocities in the according mediums, we can effectively optimize the PA image quality as the experiments proved, which might benefit future research in biomedical imaging science.
