The remarkable experimental progress in the studies of collisionless shockwave（CS） in laboratories employing highpower lasers is briefly reviewed. The results show that CS can be generated in laser-produced plasmas ...The remarkable experimental progress in the studies of collisionless shockwave（CS） in laboratories employing highpower lasers is briefly reviewed. The results show that CS can be generated in laser-produced plasmas due to the microturbulence associated with instabilities. CS is one of the most important astronomical phenomena. It has been found in supernova remnants（SNRs）, Sun–Earth space, etc. This paper focuses on CS in ways relevant to SNRs. Laboratory astrophysics（LA）, a new interdisciplinary frontier of astrophysics, plasma and laser physics, has developed rapidly in recent years. As an accessory to the astronomical observation, LA experimenters can closely study some astronomical events scaled-down to controllable phenomena.展开更多
Low intensity shockwave (LiSW) treatment is known to improve revascularization. The method has been evaluated and is used to treat vasculogenic erectile dysfunction (ED). The present study aimed to demonstrate the eff...Low intensity shockwave (LiSW) treatment is known to improve revascularization. The method has been evaluated and is used to treat vasculogenic erectile dysfunction (ED). The present study aimed to demonstrate the efficacy of a linear focused piezoelectric shockwave device (Richard Wolf/ELvationPiezowave<sup>2</sup>) to treat patients with vasculogenic ED using a novel linear shockwave tissue coverage LSTC-ED<sup><sup>®</sup> </sup>technique. A total of 75 patients were treated using the Piezowave<sup>2</sup> device and the LSTC-ED<sup><sup>®</sup></sup> technique. Patients’ erectile function was evaluated using the modified IIEF-5 (International Index of Erectile Function) scale at the beginning of treatment and at 1 month post treatment;patients were additionally questioned using our own Treatment Satisfaction Questionnaire (TSQ). The study also included a group of 50 patients treated by placebo;the outcomes of both groups were compared. The average IIEF-5 score of patients in the treatment group increased from 14.4 at baseline to 18.6 at 1 month post treatment. According to the IIEF-5 scale, treatment was successful in 81.33% of patients (61/75). According to the Treatment Satisfaction Questionnaire (answers 1 to 3 of the TSQ), treatment was successful in 77.3% of patients (58/75). In the placebo group of 50 patients only 5 patients showed an improvement based on IIEF score, and 8 reported an improvement based on their answers to the TSQ. No significant adverse effects were observed during treatment or in the follow-up period. The Piezowave<sup>2</sup> device and the LSTC-ED<sup><sup>®</sup> </sup>technique proved to be suitable and effective to treat erectile dysfunction.展开更多
High-speed railway tunnels in various countries have continuously reported accidents of vault falling concrete blocks.Once the concrete block falling occurs,serious consequences follow,and traffic safety may be endang...High-speed railway tunnels in various countries have continuously reported accidents of vault falling concrete blocks.Once the concrete block falling occurs,serious consequences follow,and traffic safety may be endangered.The aerodynamic shockwave evolves from the initial compression wave may be an important inducement causing the tunnel lining cracks to grow and form falling concrete blocks.A joint calculation framework is established based on ANSYS Fluent,ABAQUS,and FRANC3D for calculating the crack tip field under the aerodynamic shockwave.The intensification effect of aerodynamic shockwaves in the crack is revealed,and the evolution characteristics of the crack tip field and the influence factors of stress intensity factor(SIF)are analyzed.Results show that(1)the aerodynamic shockwave intensifies after entering the crack,resulting in more significant pressure in the crack than the input pressure.The maximum pressure of the inclined and longitudinal cracks is higher than the corresponding values of the circumferential crack,respectively.(2)The maximum SIF of the circumferential,inclined,and longitudinal crack appears at 0.5,0.68,and 0.78 times the crack front length.The maximum SIF of the circumferential crack is higher than that of the inclined and longitudinal crack.The possibility of crack growth of the circumferential crack is the highest under aerodynamic shockwaves.(3)The influence of train speed on the SIF of the circumferential crack is more than 40%.When the train speed,crack depth,and crack length change,the change of pressure in the crack is the direct cause of the change of SIF.展开更多
Objective We aimed to compare the clinical outcomes of intravenous urography-assisted fluoroscopy-guided shockwave lithotripsy for radiolucent ureteral stones and standard shockwave lithotripsy for radiopaque ureteral...Objective We aimed to compare the clinical outcomes of intravenous urography-assisted fluoroscopy-guided shockwave lithotripsy for radiolucent ureteral stones and standard shockwave lithotripsy for radiopaque ureteral stones.Methods We retrospectively reviewed 734 patients with ureteral stones treated by fluoroscopy-guided shockwave lithotripsy between March 2014 and March 2021.The primary outcome was a stone-free rate with one session within 30 days,defined as no residual stones without auxiliary treatment.The multivariate analysis was used to examine whether the intravenous urography use predicted treatment success.Furthermore,we compared the outcomes using propensity score matching.Results Ninety-eight patients underwent the intravenous urography use protocol(Group I),and the remaining 636 patients underwent the non-intravenous urography protocol(Group N).Stone-free rates with one session within 30 days were 38%and 32%in groups I and N,respectively(p=0.3).No statistical differences were observed in the conversion rate to ureteroscopy(p=0.3)or complication rate(p=0.7)between Group I and Group N.One patient who developed skin redness was considered a complication of the contrast medium.Propensity score matching examined 88 matched pairs.Treatment success was obtained in 31(35%)patients in Group I and 33(38%)patients in Group N(p=0.9)within 30 days with one session.Conclusion Radiolucent stones can be safely and effectively treated by shockwave lithotripsy with intravenous urography.展开更多
This paper presents a new technique,termed femtosecond laser shock peening ablation in liquids(fs-LSPAL),which can realize simultaneous crack micro/nanomanufacturing and hierarchical micro/nanolaser ablation,giving ri...This paper presents a new technique,termed femtosecond laser shock peening ablation in liquids(fs-LSPAL),which can realize simultaneous crack micro/nanomanufacturing and hierarchical micro/nanolaser ablation,giving rise to the formation of diverse multiscale hierarchical structures,such as macroporous ratcheted structures and enéchelon microfringes decorated with parabolic nanoripples.Through analysis of surface morphologies,many phenomena have been confirmed to take place during fs-LSPAL,including enéchelon cracks,nanostriation,ripple densification,crack branching,and selective formation of high spatial frequency laser-induced periodic surface structures of 100–200 nm in period.At a high laser power of 700 mW,fs-LSPAL at scanning speeds of 0.2 mm s^-1 and 1 mm s^-1 enables the generation of height-fluctuated and height-homogeneous hierarchical structures,respectively.The height-fluctuated structures can be used to induce‘colony’aggregates of embryonic EB3 stem cells.At 200 mW,fs-LSPAL at 1 mm s^-1 is capable of producing homogeneous tilt macroporous structures with cracked structures interleaved among them,which are the synergistic effects of bubble-induced light refraction/reflection ablation and cracks.As shown in this paper,the conventional laser ablation technique integrated with its self-driven unconventional cracking under extreme conditions expands the horizons of extreme manufacturing and offers more opportunities for complex surface structuring,which can potentially be used for biological applications.展开更多
This paper introduces computational fluid used in aerospace engineering, to deal with surface physical and mathematical foundations of CFD, this traffic problems such as queue/platoon distribution, dynamics （CFD）, a...This paper introduces computational fluid used in aerospace engineering, to deal with surface physical and mathematical foundations of CFD, this traffic problems such as queue/platoon distribution, dynamics （CFD）, a numerical traffic flow related problems. approach widely and successfully After a brief introduction of the paper develops CFD implementation methodology for modeling shockwave propagation, and prediction of system performance. Some theoretical and practical applications are discussed in this paper to illustrate the implementation methodology. It is found that CFD approach can facilitate a superior insight into the formation and propagation of congestion, thereby supporting more effective methods to alleviate congestion. In addition, CFD approach is found capable of assessing freeway system performance using less ITS detectors, and enhancing the coverage and reliability of a traffic detection system.展开更多
Ventilated cavitation has been successfully employed as ship drag reduction technology and potentially can mitigate flowinduced vibration. The obtained successes were based on solutions of design problems considered i...Ventilated cavitation has been successfully employed as ship drag reduction technology and potentially can mitigate flowinduced vibration. The obtained successes were based on solutions of design problems considered in the framework of ideal fluid theory with their following validation by towing tank tests. However, various aspects of the interaction of ventilated cavities with the viscous flows around the ship hulls remain unclear, whereas there is usually no possibility to simultaneously keep the full-scale Froude number and cavitation number in the test facilities. So, the further progress of the application of ventilated cavitation substantially depends on the ability of computational tools to predict this interaction. This paper briefly describes the state-of-the-art computation of ventilated cavitation and points out the most challenging unsolved problems that appeared in the model tests (prediction of air demand by cavities, ventilation effect on ship drag, on hydrofoil lift, and on the propagation of shock waves in cavities).展开更多
基金Project supported by the National Basic Research Program of China(Grant No.2013CBA01501)the National Natural Science Foundation of China(Grant No.11135012)
文摘The remarkable experimental progress in the studies of collisionless shockwave（CS） in laboratories employing highpower lasers is briefly reviewed. The results show that CS can be generated in laser-produced plasmas due to the microturbulence associated with instabilities. CS is one of the most important astronomical phenomena. It has been found in supernova remnants（SNRs）, Sun–Earth space, etc. This paper focuses on CS in ways relevant to SNRs. Laboratory astrophysics（LA）, a new interdisciplinary frontier of astrophysics, plasma and laser physics, has developed rapidly in recent years. As an accessory to the astronomical observation, LA experimenters can closely study some astronomical events scaled-down to controllable phenomena.
文摘Low intensity shockwave (LiSW) treatment is known to improve revascularization. The method has been evaluated and is used to treat vasculogenic erectile dysfunction (ED). The present study aimed to demonstrate the efficacy of a linear focused piezoelectric shockwave device (Richard Wolf/ELvationPiezowave<sup>2</sup>) to treat patients with vasculogenic ED using a novel linear shockwave tissue coverage LSTC-ED<sup><sup>®</sup> </sup>technique. A total of 75 patients were treated using the Piezowave<sup>2</sup> device and the LSTC-ED<sup><sup>®</sup></sup> technique. Patients’ erectile function was evaluated using the modified IIEF-5 (International Index of Erectile Function) scale at the beginning of treatment and at 1 month post treatment;patients were additionally questioned using our own Treatment Satisfaction Questionnaire (TSQ). The study also included a group of 50 patients treated by placebo;the outcomes of both groups were compared. The average IIEF-5 score of patients in the treatment group increased from 14.4 at baseline to 18.6 at 1 month post treatment. According to the IIEF-5 scale, treatment was successful in 81.33% of patients (61/75). According to the Treatment Satisfaction Questionnaire (answers 1 to 3 of the TSQ), treatment was successful in 77.3% of patients (58/75). In the placebo group of 50 patients only 5 patients showed an improvement based on IIEF score, and 8 reported an improvement based on their answers to the TSQ. No significant adverse effects were observed during treatment or in the follow-up period. The Piezowave<sup>2</sup> device and the LSTC-ED<sup><sup>®</sup> </sup>technique proved to be suitable and effective to treat erectile dysfunction.
基金funded by the National Natural Science Foundation of China(Grant Nos.51978670 and 52308419)the Science and Technology Research and Development Program of China railway group limited(Grant Nos.2021-Major-01 and 2022-Key-22)+3 种基金the Fundamental Research Funds for the Central Universities of Central South University(Grant No.2023ZZTS0369)the Guangdong Basic and Applied Basic Research Foundation Project(Grant No.2021B1515130006)the Innovation and Technology Commission of Hong Kong,China(Grant No.K-BBY1)the Hong Kong Polytechnic University’s Postdoc Matching Fund Scheme(Grant No.1-W21Q).
文摘High-speed railway tunnels in various countries have continuously reported accidents of vault falling concrete blocks.Once the concrete block falling occurs,serious consequences follow,and traffic safety may be endangered.The aerodynamic shockwave evolves from the initial compression wave may be an important inducement causing the tunnel lining cracks to grow and form falling concrete blocks.A joint calculation framework is established based on ANSYS Fluent,ABAQUS,and FRANC3D for calculating the crack tip field under the aerodynamic shockwave.The intensification effect of aerodynamic shockwaves in the crack is revealed,and the evolution characteristics of the crack tip field and the influence factors of stress intensity factor(SIF)are analyzed.Results show that(1)the aerodynamic shockwave intensifies after entering the crack,resulting in more significant pressure in the crack than the input pressure.The maximum pressure of the inclined and longitudinal cracks is higher than the corresponding values of the circumferential crack,respectively.(2)The maximum SIF of the circumferential,inclined,and longitudinal crack appears at 0.5,0.68,and 0.78 times the crack front length.The maximum SIF of the circumferential crack is higher than that of the inclined and longitudinal crack.The possibility of crack growth of the circumferential crack is the highest under aerodynamic shockwaves.(3)The influence of train speed on the SIF of the circumferential crack is more than 40%.When the train speed,crack depth,and crack length change,the change of pressure in the crack is the direct cause of the change of SIF.
文摘Objective We aimed to compare the clinical outcomes of intravenous urography-assisted fluoroscopy-guided shockwave lithotripsy for radiolucent ureteral stones and standard shockwave lithotripsy for radiopaque ureteral stones.Methods We retrospectively reviewed 734 patients with ureteral stones treated by fluoroscopy-guided shockwave lithotripsy between March 2014 and March 2021.The primary outcome was a stone-free rate with one session within 30 days,defined as no residual stones without auxiliary treatment.The multivariate analysis was used to examine whether the intravenous urography use predicted treatment success.Furthermore,we compared the outcomes using propensity score matching.Results Ninety-eight patients underwent the intravenous urography use protocol(Group I),and the remaining 636 patients underwent the non-intravenous urography protocol(Group N).Stone-free rates with one session within 30 days were 38%and 32%in groups I and N,respectively(p=0.3).No statistical differences were observed in the conversion rate to ureteroscopy(p=0.3)or complication rate(p=0.7)between Group I and Group N.One patient who developed skin redness was considered a complication of the contrast medium.Propensity score matching examined 88 matched pairs.Treatment success was obtained in 31(35%)patients in Group I and 33(38%)patients in Group N(p=0.9)within 30 days with one session.Conclusion Radiolucent stones can be safely and effectively treated by shockwave lithotripsy with intravenous urography.
基金the financial support by RIKEN FY2019‘Emerging Collaboration Seed’of‘Collaboration Seed Fund’(Grant No.100948-201901010000-340130)。
文摘This paper presents a new technique,termed femtosecond laser shock peening ablation in liquids(fs-LSPAL),which can realize simultaneous crack micro/nanomanufacturing and hierarchical micro/nanolaser ablation,giving rise to the formation of diverse multiscale hierarchical structures,such as macroporous ratcheted structures and enéchelon microfringes decorated with parabolic nanoripples.Through analysis of surface morphologies,many phenomena have been confirmed to take place during fs-LSPAL,including enéchelon cracks,nanostriation,ripple densification,crack branching,and selective formation of high spatial frequency laser-induced periodic surface structures of 100–200 nm in period.At a high laser power of 700 mW,fs-LSPAL at scanning speeds of 0.2 mm s^-1 and 1 mm s^-1 enables the generation of height-fluctuated and height-homogeneous hierarchical structures,respectively.The height-fluctuated structures can be used to induce‘colony’aggregates of embryonic EB3 stem cells.At 200 mW,fs-LSPAL at 1 mm s^-1 is capable of producing homogeneous tilt macroporous structures with cracked structures interleaved among them,which are the synergistic effects of bubble-induced light refraction/reflection ablation and cracks.As shown in this paper,the conventional laser ablation technique integrated with its self-driven unconventional cracking under extreme conditions expands the horizons of extreme manufacturing and offers more opportunities for complex surface structuring,which can potentially be used for biological applications.
文摘This paper introduces computational fluid used in aerospace engineering, to deal with surface physical and mathematical foundations of CFD, this traffic problems such as queue/platoon distribution, dynamics （CFD）, a numerical traffic flow related problems. approach widely and successfully After a brief introduction of the paper develops CFD implementation methodology for modeling shockwave propagation, and prediction of system performance. Some theoretical and practical applications are discussed in this paper to illustrate the implementation methodology. It is found that CFD approach can facilitate a superior insight into the formation and propagation of congestion, thereby supporting more effective methods to alleviate congestion. In addition, CFD approach is found capable of assessing freeway system performance using less ITS detectors, and enhancing the coverage and reliability of a traffic detection system.
文摘Ventilated cavitation has been successfully employed as ship drag reduction technology and potentially can mitigate flowinduced vibration. The obtained successes were based on solutions of design problems considered in the framework of ideal fluid theory with their following validation by towing tank tests. However, various aspects of the interaction of ventilated cavities with the viscous flows around the ship hulls remain unclear, whereas there is usually no possibility to simultaneously keep the full-scale Froude number and cavitation number in the test facilities. So, the further progress of the application of ventilated cavitation substantially depends on the ability of computational tools to predict this interaction. This paper briefly describes the state-of-the-art computation of ventilated cavitation and points out the most challenging unsolved problems that appeared in the model tests (prediction of air demand by cavities, ventilation effect on ship drag, on hydrofoil lift, and on the propagation of shock waves in cavities).
