A hybrid identification model based on multilayer artificial neural networks(ANNs) and particle swarm optimization(PSO) algorithm is developed to improve the simultaneous identification efficiency of thermal conductiv...A hybrid identification model based on multilayer artificial neural networks(ANNs) and particle swarm optimization(PSO) algorithm is developed to improve the simultaneous identification efficiency of thermal conductivity and effective absorption coefficient of semitransparent materials.For the direct model,the spherical harmonic method and the finite volume method are used to solve the coupled conduction-radiation heat transfer problem in an absorbing,emitting,and non-scattering 2D axisymmetric gray medium in the background of laser flash method.For the identification part,firstly,the temperature field and the incident radiation field in different positions are chosen as observables.Then,a traditional identification model based on PSO algorithm is established.Finally,multilayer ANNs are built to fit and replace the direct model in the traditional identification model to speed up the identification process.The results show that compared with the traditional identification model,the time cost of the hybrid identification model is reduced by about 1 000 times.Besides,the hybrid identification model remains a high level of accuracy even with measurement errors.展开更多
This paper outlines a concurrent engineering environment that supports interaction between members of a geographically dispersed multidisciplinary team who is engaged in engineering design activities. Some ideas of en...This paper outlines a concurrent engineering environment that supports interaction between members of a geographically dispersed multidisciplinary team who is engaged in engineering design activities. Some ideas of engineering design, especially conceptual design are reviewed. A deeper scientific analysis of intelligent design is discussed. A new problem solving strategy and methodologies to implement cooperative design are proposed. Finally, a conceptual model of a blackboard system for accomplishing conceptual design automation is presented. Its fundamental principles, system organization and key implementation techniques are investigated in detail.展开更多
As a new group in the process of socio-economic transformation, female members of the Chinese floating population have negative self-identities rooted in the traditional gender discrimination in China society. This im...As a new group in the process of socio-economic transformation, female members of the Chinese floating population have negative self-identities rooted in the traditional gender discrimination in China society. This impacts negatively on female migrants1 both physiologically and psychologically, disadvantaging them in the pursuit of resources, opportunities and rights. It is therefore necessary to positively influence the self-image of female migrants so as to ensure their rights, further their interests and ultimately to achieve gender equality.展开更多
Enterovirus 71 (EV71) is a common cause of Hand, foot, and mouth disease (HFMD) and may also cause severe neurological diseases, such as encephalitis and poliomyelitis-like paralysis. To examine the genetic divers...Enterovirus 71 (EV71) is a common cause of Hand, foot, and mouth disease (HFMD) and may also cause severe neurological diseases, such as encephalitis and poliomyelitis-like paralysis. To examine the genetic diversity of EV71, we determined and analyzed the complete VP1 sequences (891 nueleotides) from nine EV71 strains isolated in Fuyang, China. We found that nine EV71 strains isolated were over 98% homologous at the nucleotide level and 93%-100% homologous tO members of the C4 subgenogroup. At the amino acid level, these Fuyang strains were 99% -100% homologous to one another, 97%-100% homologous to members of the C4 subgenogroup, and the histidine(H) at amino acid position 22 was conserved among the Fuyang strains. The results indicate that Fuyang isolates belong to genotype C4, and an H at position 22 appears to be a marker for the Fuyang strains.展开更多
Oscillator IC technique is developed by combining injecting synchronization technique with a ring VCO.Using the technique,a novel 2 488GHz of monolithical integrated injected synchronized ring VCO (ISRVCO) is realize...Oscillator IC technique is developed by combining injecting synchronization technique with a ring VCO.Using the technique,a novel 2 488GHz of monolithical integrated injected synchronized ring VCO (ISRVCO) is realized in a standard 0 25μm CMOS process.The ISRVCO is characterized by the following performances: -100dBc /Hz@1MHz at free running frequency,-91 7dBc/Hz@10kHz when injection is locked.With the 3 3V of power supply,the tuning range is 150MHz and the locking range is 100MHz with 50m V p p signal injection.展开更多
In order to effectively reduce the uncertainty error of mobile robot localization with a single sensor and improve the accuracy and robustness of robot localization and mapping,a mobile robot localization algorithm ba...In order to effectively reduce the uncertainty error of mobile robot localization with a single sensor and improve the accuracy and robustness of robot localization and mapping,a mobile robot localization algorithm based on multi-sensor information fusion(MSIF)was proposed.In this paper,simultaneous localization and mapping(SLAM)was realized on the basis of laser Rao-Blackwellized particle filter(RBPF)-SLAM algorithm and graph-based optimization theory was used to constrain and optimize the pose estimation results of Monte Carlo localization.The feature point extraction and quadrilateral closed loop matching algorithm based on oriented FAST and rotated BRIEF(ORB)were improved aiming at the problems of generous calculation and low tracking accuracy in visual information processing by means of the three-dimensional(3D)point feature in binocular visual reconstruction environment.Factor graph model was used for the information fusion under the maximum posterior probability criterion for laser RBPF-SLAM localization and binocular visual localization.The results of simulation and experiment indicate that localization accuracy of the above-mentioned method is higher than that of traditional RBPF-SLAM algorithm and general improved algorithms,and the effectiveness and usefulness of the proposed method are verified.展开更多
Objective To evaluate whether cardiac resynchronisation therapy (CRT) implantation was feasible and safe in octogenarians and the asso- ciation with symptoms. Methods Consecutive patients undergoing CRT implantation...Objective To evaluate whether cardiac resynchronisation therapy (CRT) implantation was feasible and safe in octogenarians and the asso- ciation with symptoms. Methods Consecutive patients undergoing CRT implantation were recruited from two UK centers. Patients grouped according to age: 〈 80 & ≥ 80 years. Baseline demographics, complications and outcomes were compared between those groups. Results A total of 439 patients were included in this study, of whom 26% were aged ≥ 80 years. Octogenarians more often received cardiac resynchronization therapy pacemaker in comparison to cardiac resynchronisation therapy-defibrillator. Upgrade from pacemaker was common in both groups (16% 〈 80 years vs. 22% ≥ 80 years, P = NS). Co-morbidities were similarly common in both groups (overall diabetes: 25%, atrial fibrillation: 23%, hypertension: 45%). More patient age ≥ 80 years had significant chronic kidney disease (CKD, estimated glomerular filtration rate 〈 45 mL/min per 1.73 m^2, 44% vs. 22%, P 〈 0.01 ). Overall complication rates (any) were similar in both groups (16% vs. 17%, P = NS). Both groups demonstrated symptomatic benefit. One-year mortality rates were almost four fold greater in octogenarians as compared with the younger cohort (13.9% vs. 3.7%, P 〈 0.01). Conclusions CRT appears to be safe in the very elderly despite extensive co-morbidity, and in particular frequent severe CKD. Symptomatic improvement appears to be meaningful. Strategies to increase the appropriate identification of elderly patients with CHF who are potential candidates for CRT are required.展开更多
An extended Kalman filter approach of simultaneous localization and mapping(SLAM) was proposed based on local maps. A local frame of reference was established periodically at the position of the robot, and then the ob...An extended Kalman filter approach of simultaneous localization and mapping(SLAM) was proposed based on local maps. A local frame of reference was established periodically at the position of the robot, and then the observations of the robot and landmarks were fused into the global frame of reference. Because of the independence of the local map, the approach does not cumulate the estimate and calculation errors which are produced by SLAM using Kalman filter directly. At the same time, it reduces the computational complexity. This method is proven correct and feasible in simulation experiments.展开更多
A gene homologous to the human Putative tumor suppressor gone QM, designated OSQM1, was isolated from rice (Oryza sativa L.) genomic DNA library using through homology screening. It contained 4 exons and 3 introns, en...A gene homologous to the human Putative tumor suppressor gone QM, designated OSQM1, was isolated from rice (Oryza sativa L.) genomic DNA library using through homology screening. It contained 4 exons and 3 introns, encoding a protein of 219 amino acids with 46 basic amino acids, leading to a high isoelectric point of 11.02. Homology search showed that this gene existed in eukaryotes and highly conserved throughout eukaryotes, suggesting an essential role of this gene. Northern Not analysis showed that it was expressed in various rice organs, but at lower level in developing flower and callus tissue than in other vegetative organs. Its expression levels in roots and leaves were influenced by different environmental factors.展开更多
Cooperative path planning is an important area in fixed-wing UAV swarm.However,avoiding multiple timevarying obstacles and avoiding local optimum are two challenges for existing approaches in a dynamic environment.Fir...Cooperative path planning is an important area in fixed-wing UAV swarm.However,avoiding multiple timevarying obstacles and avoiding local optimum are two challenges for existing approaches in a dynamic environment.Firstly,a normalized artificial potential field optimization is proposed by reconstructing a novel function with anisotropy in each dimension,which can make the flight speed of a fixed UAV swarm independent of the repulsive/attractive gain coefficient and avoid trapping into local optimization and local oscillation.Then,taking into account minimum velocity and turning angular velocity of fixed-wing UAV swarm,a strategy of decomposing target vector to avoid moving obstacles and pop-up threats is proposed.Finally,several simulations are carried out to illustrate superiority and effectiveness.展开更多
Background Clinical outcomes of cardiac resynchronization therapy (CRT) in patients over the age of 80 have not been well de-scribed.MethodsWe retrospectively identified 96 consecutive patients≥ 80 years old who un...Background Clinical outcomes of cardiac resynchronization therapy (CRT) in patients over the age of 80 have not been well de-scribed.MethodsWe retrospectively identified 96 consecutive patients≥ 80 years old who underwent an initial implant or an upgrade to CRT, with or without defibrillator (CRT-Dvs. CRT-P), at our institution between January 2003 and July 2008. The control cohort consisted of 177 randomly selected patients 〈 80 years old undergoing CRT implant during the same time period. The primary efficacy endpoint was all-cause mortality at 36 months, assessed by Kaplan-Meier time to first event curves.Results In the octogenarian cohort, mean age at CRT implant was 83.1 ± 2.9 yearsvs. 60.1 ± 8.8 years among controls (P 〈 0.001). Across both groups, 70% were male, mean left ventricular ejection fraction (LVEF) was 24.8% ± 14.1% and QRS duration was 154 ± 24.8 ms, without significant differences between groups. Octo-genarians were more likely to have ischemic cardiomyopathy (74%vs. 37%,P 〈 0.001) and more likely to undergo upgrade to CRT instead of an initial implant (42%vs. 19%,P 〈 0.001). The rate of appropriate defibrillator shocks was lower among octogenarians (14%vs. 27%,P = 0.02) whereas the rate of inappropriate shocks was similar (3%vs. 6%,P = 0.55). At 36 months, there was no significant difference in the rate of all-cause mortality between octogenarians (11%) and controls (8%,P = 0.381).ConclusionAppropriately selected octogenarians who are candidates for CRT have similar intermediate-term mortality compared to younger patients receiving CRT.展开更多
AIM: To investigate the expression patterns of TTYH2 in the human colon cancer and colon cancer cell lines and to evaluate the inhibitory effect of small interfering RNA (siRNA) on the expression of TTYH2 in colon can...AIM: To investigate the expression patterns of TTYH2 in the human colon cancer and colon cancer cell lines and to evaluate the inhibitory effect of small interfering RNA (siRNA) on the expression of TTYH2 in colon cancer cell lines.METHODS: We investigated the expression patterns of TTYH2 in colon cancer, adjacent non-tumorous colon mucosa, and cancer cell lines (DLD-1, caco-2, and Lovo) by RT-PCR. Furthermore, a siRNA plasmid expression vector against TTYH2 was constructed and transfected into DLD-1 and Caco-2 with LipofectamineTM 2000. The down regulation of TTYH2 expression was detected by RT-PCR and the role of siRNA in inducing cell proliferation and cell aggregation was evaluated by MTT and aggregation assay.RESULTS: TTYH2 gene expression in colon cancer tissue was significantly up-regulated compared with normal colonic mucosa (1.23 ± 0.404 vs 0.655 ± 0.373, P = 0.0103). Colon cancer derived cell lines including DLD-1, Caco-2, and Lovo also expressed high levels of TTYH2. In contrast, transfection with siRNA-TTYH2 signifi cantly inhibited both proliferation and scattering of these cancer cell lines.CONCLUSION: The present work demonstrates, for the fi rst time, that the TTYH2 gene expression is signifi cantly up-regulated in colon cancer. The TTYH2 gene may play an important role in regulating both proliferating andmetastatic potentials of colorectal cancer.展开更多
The application of multiple UAVs in complicated tasks has been widely explored in recent years.Due to the advantages of flexibility,cheapness and consistence,the performance of heterogeneous multi-UAVs with proper coo...The application of multiple UAVs in complicated tasks has been widely explored in recent years.Due to the advantages of flexibility,cheapness and consistence,the performance of heterogeneous multi-UAVs with proper cooperative task allocation is superior to over the single UAV.Accordingly,several constraints should be satisfied to realize the efficient cooperation,such as special time-window,variant equipment,specified execution sequence.Hence,a proper task allocation in UAVs is the crucial point for the final success.The task allocation problem of the heterogeneous UAVs can be formulated as a multi-objective optimization problem coupled with the UAV dynamics.To this end,a multi-layer encoding strategy and a constraint scheduling method are designed to handle the critical logical and physical constraints.In addition,four optimization objectives:completion time,target reward,UAV damage,and total range,are introduced to evaluate various allocation plans.Subsequently,to efficiently solve the multi-objective optimization problem,an improved multi-objective quantum-behaved particle swarm optimization(IMOQPSO)algorithm is proposed.During this algorithm,a modified solution evaluation method is designed to guide algorithmic evolution;both the convergence and distribution of particles are considered comprehensively;and boundary solutions which may produce some special allocation plans are preserved.Moreover,adaptive parameter control and mixed update mechanism are also introduced in this algorithm.Finally,both the proposed model and algorithm are verified by simulation experiments.展开更多
The synchronous tracking control problem of a hydraulic parallel manipulator with six degrees of freedom (DOF) is complicated since the inclusion of hydraulic elements increases the order of the system.To solve this p...The synchronous tracking control problem of a hydraulic parallel manipulator with six degrees of freedom (DOF) is complicated since the inclusion of hydraulic elements increases the order of the system.To solve this problem,cascade control method with an inner/outer-loop control structure is used,which masks the hydraulic dynamics with the inner-loop so that the designed controller takes into account of both the mechanical dynamics and the hydraulic dynamics of the manipulator.Furthermore,a cross-coupling control approach is introduced to the synchronous tracking control of the manipulator.The position synchronization error is developed by considering motion synchronization between each actuator joint and its adjacent ones based on the synchronous goal.Then,with the feedback of both position error and synchronization error,the tracking is proven to guarantee that both the position errors and synchronization errors asymptotically converge to zero.Moreover,the effectiveness of the proposed approach is verified by the experimental results performed with a 6-DOF hydraulic parallel manipulator.展开更多
Background The Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery (SYNTAX)-score is a validated tool for risk stratification and revascularization strategy selection in patients with c...Background The Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery (SYNTAX)-score is a validated tool for risk stratification and revascularization strategy selection in patients with complex coronary artery disease. The aim of this study was to analyse its age-related prognostic value. Methods SYNTAX-score was calculated in 1331 all-comer patients undergoing percutaneous coronary intervention (PCI): 463 patients ≥ 75 years and 868 patients 〈 75 years. Outcomes of interest were all-cause mortality at one and two years. Results A significant interaction of age and SYNTAX-score for mortality was observed at two-year (Pinteraction= 0.019) but not at one-year follow-up (Pinteraction= 0.594). In multivariable analysis, SYNTAX-score independently predicted 1-year mortality in both age groups (〈 75 years, hazard ratio (HR): 1.43, 95% confidence intervals (CI): 1.03-2.00, P = 0.034; and 〉 75 years, HR: 1.37, 95% CI: 1.01-1.85, P = 0.042), but only two-year mortality among younger patients (〈 75 years, HR: 1.33, 95% CI: 1.01-1.76, P = 0.041; and ≥ 75 years, HR: 1.11, 95% CI: 0.87-1.41, P = 0.394). SYNTAX-score tertiles were useful to stratify 1-year mortality in both, patients 〈 75 years (SYNTAX-score 〈 9, 3.8%; 9-20, 5.3%; 〉 20, 10.3%; P = 0.004) and 〉 75 years (SYNTAX-score 〈 11, 5.7%; 11-22.5, 16.1%; 〉 22.5, 18.7%; P = 0.003), but two-year mortality only among patients 〈 75 years (SYNTAX-score 〈 9, 6.5%; 9-20, 7.6%; ≥ 20, 15%; P 〈 0.001) and not among ≥ 75 years old patients (SYNTAX-score 〈 11, 19.4%; 11-22.5, 26.3%; _〉 22.5, 27.9%; P = 0.138). Conclusions Age modi- fies the impact of the SYNTAX-score on longer-term mortality after PCI. Among patients 〈 75 years, the SYNTAX-score independently predicts the risk of death at one and two years after PCI, while among patients 〉 75 years its predictive role is limited to the first year after PCI. Further studies are needed to evaluate the value of SYNTAX-score for selecting the most appropriate revascularization strategy among elderly patients.展开更多
基金supported by the Fundamental Research Funds for the Central Universities (No.3122020072)the Multi-investment Project of Tianjin Applied Basic Research(No.23JCQNJC00250)。
文摘A hybrid identification model based on multilayer artificial neural networks(ANNs) and particle swarm optimization(PSO) algorithm is developed to improve the simultaneous identification efficiency of thermal conductivity and effective absorption coefficient of semitransparent materials.For the direct model,the spherical harmonic method and the finite volume method are used to solve the coupled conduction-radiation heat transfer problem in an absorbing,emitting,and non-scattering 2D axisymmetric gray medium in the background of laser flash method.For the identification part,firstly,the temperature field and the incident radiation field in different positions are chosen as observables.Then,a traditional identification model based on PSO algorithm is established.Finally,multilayer ANNs are built to fit and replace the direct model in the traditional identification model to speed up the identification process.The results show that compared with the traditional identification model,the time cost of the hybrid identification model is reduced by about 1 000 times.Besides,the hybrid identification model remains a high level of accuracy even with measurement errors.
文摘This paper outlines a concurrent engineering environment that supports interaction between members of a geographically dispersed multidisciplinary team who is engaged in engineering design activities. Some ideas of engineering design, especially conceptual design are reviewed. A deeper scientific analysis of intelligent design is discussed. A new problem solving strategy and methodologies to implement cooperative design are proposed. Finally, a conceptual model of a blackboard system for accomplishing conceptual design automation is presented. Its fundamental principles, system organization and key implementation techniques are investigated in detail.
文摘As a new group in the process of socio-economic transformation, female members of the Chinese floating population have negative self-identities rooted in the traditional gender discrimination in China society. This impacts negatively on female migrants1 both physiologically and psychologically, disadvantaging them in the pursuit of resources, opportunities and rights. It is therefore necessary to positively influence the self-image of female migrants so as to ensure their rights, further their interests and ultimately to achieve gender equality.
基金Scientific Research Fund of Institute of Pathogen Biology(2008IPB108)
文摘Enterovirus 71 (EV71) is a common cause of Hand, foot, and mouth disease (HFMD) and may also cause severe neurological diseases, such as encephalitis and poliomyelitis-like paralysis. To examine the genetic diversity of EV71, we determined and analyzed the complete VP1 sequences (891 nueleotides) from nine EV71 strains isolated in Fuyang, China. We found that nine EV71 strains isolated were over 98% homologous at the nucleotide level and 93%-100% homologous tO members of the C4 subgenogroup. At the amino acid level, these Fuyang strains were 99% -100% homologous to one another, 97%-100% homologous to members of the C4 subgenogroup, and the histidine(H) at amino acid position 22 was conserved among the Fuyang strains. The results indicate that Fuyang isolates belong to genotype C4, and an H at position 22 appears to be a marker for the Fuyang strains.
文摘Oscillator IC technique is developed by combining injecting synchronization technique with a ring VCO.Using the technique,a novel 2 488GHz of monolithical integrated injected synchronized ring VCO (ISRVCO) is realized in a standard 0 25μm CMOS process.The ISRVCO is characterized by the following performances: -100dBc /Hz@1MHz at free running frequency,-91 7dBc/Hz@10kHz when injection is locked.With the 3 3V of power supply,the tuning range is 150MHz and the locking range is 100MHz with 50m V p p signal injection.
基金Natural Science Foundation of Shaanxi Province(No.2019JQ-004)Scientific Research Plan Projects of Shaanxi Education Department(No.18JK0438)Youth Talent Promotion Project of Shaanxi Province(No.20180112)。
文摘In order to effectively reduce the uncertainty error of mobile robot localization with a single sensor and improve the accuracy and robustness of robot localization and mapping,a mobile robot localization algorithm based on multi-sensor information fusion(MSIF)was proposed.In this paper,simultaneous localization and mapping(SLAM)was realized on the basis of laser Rao-Blackwellized particle filter(RBPF)-SLAM algorithm and graph-based optimization theory was used to constrain and optimize the pose estimation results of Monte Carlo localization.The feature point extraction and quadrilateral closed loop matching algorithm based on oriented FAST and rotated BRIEF(ORB)were improved aiming at the problems of generous calculation and low tracking accuracy in visual information processing by means of the three-dimensional(3D)point feature in binocular visual reconstruction environment.Factor graph model was used for the information fusion under the maximum posterior probability criterion for laser RBPF-SLAM localization and binocular visual localization.The results of simulation and experiment indicate that localization accuracy of the above-mentioned method is higher than that of traditional RBPF-SLAM algorithm and general improved algorithms,and the effectiveness and usefulness of the proposed method are verified.
文摘Objective To evaluate whether cardiac resynchronisation therapy (CRT) implantation was feasible and safe in octogenarians and the asso- ciation with symptoms. Methods Consecutive patients undergoing CRT implantation were recruited from two UK centers. Patients grouped according to age: 〈 80 & ≥ 80 years. Baseline demographics, complications and outcomes were compared between those groups. Results A total of 439 patients were included in this study, of whom 26% were aged ≥ 80 years. Octogenarians more often received cardiac resynchronization therapy pacemaker in comparison to cardiac resynchronisation therapy-defibrillator. Upgrade from pacemaker was common in both groups (16% 〈 80 years vs. 22% ≥ 80 years, P = NS). Co-morbidities were similarly common in both groups (overall diabetes: 25%, atrial fibrillation: 23%, hypertension: 45%). More patient age ≥ 80 years had significant chronic kidney disease (CKD, estimated glomerular filtration rate 〈 45 mL/min per 1.73 m^2, 44% vs. 22%, P 〈 0.01 ). Overall complication rates (any) were similar in both groups (16% vs. 17%, P = NS). Both groups demonstrated symptomatic benefit. One-year mortality rates were almost four fold greater in octogenarians as compared with the younger cohort (13.9% vs. 3.7%, P 〈 0.01). Conclusions CRT appears to be safe in the very elderly despite extensive co-morbidity, and in particular frequent severe CKD. Symptomatic improvement appears to be meaningful. Strategies to increase the appropriate identification of elderly patients with CHF who are potential candidates for CRT are required.
基金Project(60234030) supported by the National Natural Science Foundation of China project(A1420060159) supported by the National Basic Research
文摘An extended Kalman filter approach of simultaneous localization and mapping(SLAM) was proposed based on local maps. A local frame of reference was established periodically at the position of the robot, and then the observations of the robot and landmarks were fused into the global frame of reference. Because of the independence of the local map, the approach does not cumulate the estimate and calculation errors which are produced by SLAM using Kalman filter directly. At the same time, it reduces the computational complexity. This method is proven correct and feasible in simulation experiments.
文摘A gene homologous to the human Putative tumor suppressor gone QM, designated OSQM1, was isolated from rice (Oryza sativa L.) genomic DNA library using through homology screening. It contained 4 exons and 3 introns, encoding a protein of 219 amino acids with 46 basic amino acids, leading to a high isoelectric point of 11.02. Homology search showed that this gene existed in eukaryotes and highly conserved throughout eukaryotes, suggesting an essential role of this gene. Northern Not analysis showed that it was expressed in various rice organs, but at lower level in developing flower and callus tissue than in other vegetative organs. Its expression levels in roots and leaves were influenced by different environmental factors.
文摘Cooperative path planning is an important area in fixed-wing UAV swarm.However,avoiding multiple timevarying obstacles and avoiding local optimum are two challenges for existing approaches in a dynamic environment.Firstly,a normalized artificial potential field optimization is proposed by reconstructing a novel function with anisotropy in each dimension,which can make the flight speed of a fixed UAV swarm independent of the repulsive/attractive gain coefficient and avoid trapping into local optimization and local oscillation.Then,taking into account minimum velocity and turning angular velocity of fixed-wing UAV swarm,a strategy of decomposing target vector to avoid moving obstacles and pop-up threats is proposed.Finally,several simulations are carried out to illustrate superiority and effectiveness.
文摘Background Clinical outcomes of cardiac resynchronization therapy (CRT) in patients over the age of 80 have not been well de-scribed.MethodsWe retrospectively identified 96 consecutive patients≥ 80 years old who underwent an initial implant or an upgrade to CRT, with or without defibrillator (CRT-Dvs. CRT-P), at our institution between January 2003 and July 2008. The control cohort consisted of 177 randomly selected patients 〈 80 years old undergoing CRT implant during the same time period. The primary efficacy endpoint was all-cause mortality at 36 months, assessed by Kaplan-Meier time to first event curves.Results In the octogenarian cohort, mean age at CRT implant was 83.1 ± 2.9 yearsvs. 60.1 ± 8.8 years among controls (P 〈 0.001). Across both groups, 70% were male, mean left ventricular ejection fraction (LVEF) was 24.8% ± 14.1% and QRS duration was 154 ± 24.8 ms, without significant differences between groups. Octo-genarians were more likely to have ischemic cardiomyopathy (74%vs. 37%,P 〈 0.001) and more likely to undergo upgrade to CRT instead of an initial implant (42%vs. 19%,P 〈 0.001). The rate of appropriate defibrillator shocks was lower among octogenarians (14%vs. 27%,P = 0.02) whereas the rate of inappropriate shocks was similar (3%vs. 6%,P = 0.55). At 36 months, there was no significant difference in the rate of all-cause mortality between octogenarians (11%) and controls (8%,P = 0.381).ConclusionAppropriately selected octogenarians who are candidates for CRT have similar intermediate-term mortality compared to younger patients receiving CRT.
文摘AIM: To investigate the expression patterns of TTYH2 in the human colon cancer and colon cancer cell lines and to evaluate the inhibitory effect of small interfering RNA (siRNA) on the expression of TTYH2 in colon cancer cell lines.METHODS: We investigated the expression patterns of TTYH2 in colon cancer, adjacent non-tumorous colon mucosa, and cancer cell lines (DLD-1, caco-2, and Lovo) by RT-PCR. Furthermore, a siRNA plasmid expression vector against TTYH2 was constructed and transfected into DLD-1 and Caco-2 with LipofectamineTM 2000. The down regulation of TTYH2 expression was detected by RT-PCR and the role of siRNA in inducing cell proliferation and cell aggregation was evaluated by MTT and aggregation assay.RESULTS: TTYH2 gene expression in colon cancer tissue was significantly up-regulated compared with normal colonic mucosa (1.23 ± 0.404 vs 0.655 ± 0.373, P = 0.0103). Colon cancer derived cell lines including DLD-1, Caco-2, and Lovo also expressed high levels of TTYH2. In contrast, transfection with siRNA-TTYH2 signifi cantly inhibited both proliferation and scattering of these cancer cell lines.CONCLUSION: The present work demonstrates, for the fi rst time, that the TTYH2 gene expression is signifi cantly up-regulated in colon cancer. The TTYH2 gene may play an important role in regulating both proliferating andmetastatic potentials of colorectal cancer.
基金Project(61801495)supported by the National Natural Science Foundation of China
文摘The application of multiple UAVs in complicated tasks has been widely explored in recent years.Due to the advantages of flexibility,cheapness and consistence,the performance of heterogeneous multi-UAVs with proper cooperative task allocation is superior to over the single UAV.Accordingly,several constraints should be satisfied to realize the efficient cooperation,such as special time-window,variant equipment,specified execution sequence.Hence,a proper task allocation in UAVs is the crucial point for the final success.The task allocation problem of the heterogeneous UAVs can be formulated as a multi-objective optimization problem coupled with the UAV dynamics.To this end,a multi-layer encoding strategy and a constraint scheduling method are designed to handle the critical logical and physical constraints.In addition,four optimization objectives:completion time,target reward,UAV damage,and total range,are introduced to evaluate various allocation plans.Subsequently,to efficiently solve the multi-objective optimization problem,an improved multi-objective quantum-behaved particle swarm optimization(IMOQPSO)algorithm is proposed.During this algorithm,a modified solution evaluation method is designed to guide algorithmic evolution;both the convergence and distribution of particles are considered comprehensively;and boundary solutions which may produce some special allocation plans are preserved.Moreover,adaptive parameter control and mixed update mechanism are also introduced in this algorithm.Finally,both the proposed model and algorithm are verified by simulation experiments.
基金Project(50375139) supported by the National Natural Science Foundation of ChinaProject(NCET-04-0545) supported by the New Century Excellent Talent Plan of the Ministry of Education of China
文摘The synchronous tracking control problem of a hydraulic parallel manipulator with six degrees of freedom (DOF) is complicated since the inclusion of hydraulic elements increases the order of the system.To solve this problem,cascade control method with an inner/outer-loop control structure is used,which masks the hydraulic dynamics with the inner-loop so that the designed controller takes into account of both the mechanical dynamics and the hydraulic dynamics of the manipulator.Furthermore,a cross-coupling control approach is introduced to the synchronous tracking control of the manipulator.The position synchronization error is developed by considering motion synchronization between each actuator joint and its adjacent ones based on the synchronous goal.Then,with the feedback of both position error and synchronization error,the tracking is proven to guarantee that both the position errors and synchronization errors asymptotically converge to zero.Moreover,the effectiveness of the proposed approach is verified by the experimental results performed with a 6-DOF hydraulic parallel manipulator.
文摘Background The Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery (SYNTAX)-score is a validated tool for risk stratification and revascularization strategy selection in patients with complex coronary artery disease. The aim of this study was to analyse its age-related prognostic value. Methods SYNTAX-score was calculated in 1331 all-comer patients undergoing percutaneous coronary intervention (PCI): 463 patients ≥ 75 years and 868 patients 〈 75 years. Outcomes of interest were all-cause mortality at one and two years. Results A significant interaction of age and SYNTAX-score for mortality was observed at two-year (Pinteraction= 0.019) but not at one-year follow-up (Pinteraction= 0.594). In multivariable analysis, SYNTAX-score independently predicted 1-year mortality in both age groups (〈 75 years, hazard ratio (HR): 1.43, 95% confidence intervals (CI): 1.03-2.00, P = 0.034; and 〉 75 years, HR: 1.37, 95% CI: 1.01-1.85, P = 0.042), but only two-year mortality among younger patients (〈 75 years, HR: 1.33, 95% CI: 1.01-1.76, P = 0.041; and ≥ 75 years, HR: 1.11, 95% CI: 0.87-1.41, P = 0.394). SYNTAX-score tertiles were useful to stratify 1-year mortality in both, patients 〈 75 years (SYNTAX-score 〈 9, 3.8%; 9-20, 5.3%; 〉 20, 10.3%; P = 0.004) and 〉 75 years (SYNTAX-score 〈 11, 5.7%; 11-22.5, 16.1%; 〉 22.5, 18.7%; P = 0.003), but two-year mortality only among patients 〈 75 years (SYNTAX-score 〈 9, 6.5%; 9-20, 7.6%; ≥ 20, 15%; P 〈 0.001) and not among ≥ 75 years old patients (SYNTAX-score 〈 11, 19.4%; 11-22.5, 26.3%; _〉 22.5, 27.9%; P = 0.138). Conclusions Age modi- fies the impact of the SYNTAX-score on longer-term mortality after PCI. Among patients 〈 75 years, the SYNTAX-score independently predicts the risk of death at one and two years after PCI, while among patients 〉 75 years its predictive role is limited to the first year after PCI. Further studies are needed to evaluate the value of SYNTAX-score for selecting the most appropriate revascularization strategy among elderly patients.