Quantum heat transport is considered as an indispensable branch of quantum thermodynamics to potentially improve performance of thermodynamic devices.We theoretically propose a dissipative qubit-photon system composed...Quantum heat transport is considered as an indispensable branch of quantum thermodynamics to potentially improve performance of thermodynamic devices.We theoretically propose a dissipative qubit-photon system composed of multiple coupled resonators interacting with a single two-level qubit,to explore the steady-state heat transport by tuning both the inter-resonator photon hopping and the qubit-photon coupling.Specifically in the three-mode case,the dramatic enhancement and suppression of the heat current into the central resonator can be modulated by the corresponding frequency,compared to the currents into two edge resonators.Moreover,fruitful cycle current components are unraveled at weak qubit-photon coupling,which are crucial to exhibit the nonmonotonic feature with increase of the reservoir temperature bias.In the one-dimensional case under the mean-field framework,the influence of the photon hopping on heat transport is analyzed.The steady-state heat current is comparatively enhanced to the single-mode limit at weak qubit-photon coupling,stemming from the nonvanishing mean-field photon excitation parameter and the additional cycle current component.We hope these obtained results may have possible applications in quantum thermodynamic manipulation and energy harvesting.展开更多
Background:Permanent atrial fibrillation (AF) is the most common form of dysrhythmia associated with atrial septal defects (ASDs) in patients older than 40 years.However,little is known about cardiac remodeling after ...Background:Permanent atrial fibrillation (AF) is the most common form of dysrhythmia associated with atrial septal defects (ASDs) in patients older than 40 years.However,little is known about cardiac remodeling after transcatheter closure in patients with permanent AF.This study was designed to compare cardiac events and remodeling effects after transcatheter closure in such patients.Methods:Clinical data of 289 adult patients older than 40 years who underwent ASD closure at our center were analyzed retrospectively.Of them,63 patients with permanent AF were assigned to the case group,and the other 226 patients without permanent AF were assigned to the control group.Cardiac events and changes in left and right cardiac cavity dimensions before the procedure and 6 months after the procedure were compared between the two groups.Results:Patients in the case group were significantly older than those in the control group.The right ventricular (RV) volume and right atrial (RA) volume were decreased significantly in both the groups during a median follow-up period of 6 months after closure (P ＜ 0.001).The left atrial dimensions,left ventricular end-systolic dimensions,left ventricular end-diastolic dimensions and left ventricular ejection fraction showed no significant change before and after the procedure in both the groups.Changes of the RV volume and RA volume in the case group were significantly smaller than those in the control group (P =0.005 and P ＜ 0.001).The New York Heart Association cardiac function was improved in both the groups during the 6 months follow-up period.Conclusions:The transcatheter closure of ASD can improve the cardiac remodeling and cardiac function in patients with or without AF.展开更多
Objective: To evaluate the feasibility and satefy of transcatheter aortic valve implantation in animals by using a new balloon-expanding valved stent. Methods: The balloon-expandable stent is made from cobalt-based a...Objective: To evaluate the feasibility and satefy of transcatheter aortic valve implantation in animals by using a new balloon-expanding valved stent. Methods: The balloon-expandable stent is made from cobalt-based alloy material and designed with a tubular, slotted structure. Fresh bovine pericardium was treated, sutured and fixed on the balloon-expandable stent. Ten healthy sheep (five males and five females), weighing an average of (25.16 ± 1.83) kg, were selected to undergo transcatheter implantation of the valve stents. The function of the valve stent was evaluated by angiography, echocardiography, and histology six months after the procedure. Results: Of the ten experimental sheep, two sheep died during the operation because the higher position of the artificial valve affected the opening of the coronary artery. We successfully implanted the aortic valve stent in other eight sheep;however, one sheep died of heart failure two weeks after the operation due to the lower position of the valve stent. The valve stents were implanted in the desired position in seven sheep. Ascending aortic angiographic and autoptic findings immediately after the operation confirmed the satisfactory location and function of the valved stent. Echocardiography, angiography, and histology at six post-operative months confirmed the satisfactory location and function of the valve stent. Conclusion: We successfully implanted our new valve stent as a replacement of native aortic valve via the transcatheter route with satisfactory outcome. Copyright ? 2015, Chinese Medical Association Production. Production and hosting by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).展开更多
Background:Lack of fluoroscopic landmarks can make valve deployment more difficult in patients with absent aortic valve (AV)calcification.The goal of this article was to evaluate the feasibility and effectiveness oftr...Background:Lack of fluoroscopic landmarks can make valve deployment more difficult in patients with absent aortic valve (AV)calcification.The goal of this article was to evaluate the feasibility and effectiveness oftranscatheter implantation of a valved stent into the AV position of a goat,assisted with a microcatheter which provides accurate positioning of coronary artery ostia to help valved stent deployment.Methods:The subjects were 10 healthy goats in this study.A microcatheter was introduced into the distal site of right coronary artery (RCA)through femoral artery sheath.A minimal thoracic surgery approach was used to access the apex of the heart.The apex of the left ventricle was punctured; a delivery catheter equipped with the valved stent was introduced over a stiffguidewire into the aorta arch.We could accurately locate the RCA ostia through the microcatheter placed in the RCA under fluoroscopy.After correct valve position was confirmed,the valved stent was implanted after rapid inflation of the balloon.The immediate outcome of the function of the valved stents was evaluated after implantation.Results:All ten devices were successfully implanted into the AV position of the goats.Immediate observation after the procedure showed that the valved stents were in the desired position after implantation by angiography,echocardiogram.No obstruction of coronary artery ostia occurred,and no moderate to severe aortic regurgitation was observed.Conclusions:When the procedure of transcatheter implantation of a balloon-expandable valved stent into the AV position of goats is assisted with microcatheter positioning coronary artery ostia,the success rate of operation can be increased in those with noncalcified AV.展开更多
基金the National Natural Science Foundation of China(Grant No.11704093)the National Natural Science Foundation of China(Grant No.12174345)+2 种基金the Opening Project of Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technologythe Jiangsu Key Disciplines of the Fourteenth Five-Year Plan(Grant No.2021135)Zhejiang Provincial Natural Science Foundation of China(Grant No.LZ22A040002)。
文摘Quantum heat transport is considered as an indispensable branch of quantum thermodynamics to potentially improve performance of thermodynamic devices.We theoretically propose a dissipative qubit-photon system composed of multiple coupled resonators interacting with a single two-level qubit,to explore the steady-state heat transport by tuning both the inter-resonator photon hopping and the qubit-photon coupling.Specifically in the three-mode case,the dramatic enhancement and suppression of the heat current into the central resonator can be modulated by the corresponding frequency,compared to the currents into two edge resonators.Moreover,fruitful cycle current components are unraveled at weak qubit-photon coupling,which are crucial to exhibit the nonmonotonic feature with increase of the reservoir temperature bias.In the one-dimensional case under the mean-field framework,the influence of the photon hopping on heat transport is analyzed.The steady-state heat current is comparatively enhanced to the single-mode limit at weak qubit-photon coupling,stemming from the nonvanishing mean-field photon excitation parameter and the additional cycle current component.We hope these obtained results may have possible applications in quantum thermodynamic manipulation and energy harvesting.
文摘Background:Permanent atrial fibrillation (AF) is the most common form of dysrhythmia associated with atrial septal defects (ASDs) in patients older than 40 years.However,little is known about cardiac remodeling after transcatheter closure in patients with permanent AF.This study was designed to compare cardiac events and remodeling effects after transcatheter closure in such patients.Methods:Clinical data of 289 adult patients older than 40 years who underwent ASD closure at our center were analyzed retrospectively.Of them,63 patients with permanent AF were assigned to the case group,and the other 226 patients without permanent AF were assigned to the control group.Cardiac events and changes in left and right cardiac cavity dimensions before the procedure and 6 months after the procedure were compared between the two groups.Results:Patients in the case group were significantly older than those in the control group.The right ventricular (RV) volume and right atrial (RA) volume were decreased significantly in both the groups during a median follow-up period of 6 months after closure (P ＜ 0.001).The left atrial dimensions,left ventricular end-systolic dimensions,left ventricular end-diastolic dimensions and left ventricular ejection fraction showed no significant change before and after the procedure in both the groups.Changes of the RV volume and RA volume in the case group were significantly smaller than those in the control group (P =0.005 and P ＜ 0.001).The New York Heart Association cardiac function was improved in both the groups during the 6 months follow-up period.Conclusions:The transcatheter closure of ASD can improve the cardiac remodeling and cardiac function in patients with or without AF.
基金The authors are grateful to LePu (BeiJing) Medical Equipment CO., LTD. This study was sup-ported by China Postdoctoral Science Foundation
文摘Objective: To evaluate the feasibility and satefy of transcatheter aortic valve implantation in animals by using a new balloon-expanding valved stent. Methods: The balloon-expandable stent is made from cobalt-based alloy material and designed with a tubular, slotted structure. Fresh bovine pericardium was treated, sutured and fixed on the balloon-expandable stent. Ten healthy sheep (five males and five females), weighing an average of (25.16 ± 1.83) kg, were selected to undergo transcatheter implantation of the valve stents. The function of the valve stent was evaluated by angiography, echocardiography, and histology six months after the procedure. Results: Of the ten experimental sheep, two sheep died during the operation because the higher position of the artificial valve affected the opening of the coronary artery. We successfully implanted the aortic valve stent in other eight sheep;however, one sheep died of heart failure two weeks after the operation due to the lower position of the valve stent. The valve stents were implanted in the desired position in seven sheep. Ascending aortic angiographic and autoptic findings immediately after the operation confirmed the satisfactory location and function of the valved stent. Echocardiography, angiography, and histology at six post-operative months confirmed the satisfactory location and function of the valve stent. Conclusion: We successfully implanted our new valve stent as a replacement of native aortic valve via the transcatheter route with satisfactory outcome. Copyright ? 2015, Chinese Medical Association Production. Production and hosting by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
基金This research was supported by China Postdoctoral Science Foundation
文摘Background:Lack of fluoroscopic landmarks can make valve deployment more difficult in patients with absent aortic valve (AV)calcification.The goal of this article was to evaluate the feasibility and effectiveness oftranscatheter implantation of a valved stent into the AV position of a goat,assisted with a microcatheter which provides accurate positioning of coronary artery ostia to help valved stent deployment.Methods:The subjects were 10 healthy goats in this study.A microcatheter was introduced into the distal site of right coronary artery (RCA)through femoral artery sheath.A minimal thoracic surgery approach was used to access the apex of the heart.The apex of the left ventricle was punctured; a delivery catheter equipped with the valved stent was introduced over a stiffguidewire into the aorta arch.We could accurately locate the RCA ostia through the microcatheter placed in the RCA under fluoroscopy.After correct valve position was confirmed,the valved stent was implanted after rapid inflation of the balloon.The immediate outcome of the function of the valved stents was evaluated after implantation.Results:All ten devices were successfully implanted into the AV position of the goats.Immediate observation after the procedure showed that the valved stents were in the desired position after implantation by angiography,echocardiogram.No obstruction of coronary artery ostia occurred,and no moderate to severe aortic regurgitation was observed.Conclusions:When the procedure of transcatheter implantation of a balloon-expandable valved stent into the AV position of goats is assisted with microcatheter positioning coronary artery ostia,the success rate of operation can be increased in those with noncalcified AV.
