AIM To compare the outcomes of retrograde intrarenal surgery(RIRS) and miniaturized percutaneous nephrolithotomy(mini-PCNL) in treating lower pole(LP) renal stones with a diameter of 1.5-2.5 cm.METHODS A total of 216 ...AIM To compare the outcomes of retrograde intrarenal surgery(RIRS) and miniaturized percutaneous nephrolithotomy(mini-PCNL) in treating lower pole(LP) renal stones with a diameter of 1.5-2.5 cm.METHODS A total of 216 patients who underwent mini-PCNL(n = 103) or RIRS n = 113) for LP stones with a diameter of 1.5-2.5 cm were enrolled between December 2015 and April 2017 at the Urology Department of Ningbo Urology and Nephrology Hospital.RESULTS Significant differences were found in the hospital stay(9.39 ± 4.01 vs 14.08 ± 5.26, P < 0.0001) and hospitalization costs(2624.5 ± 513.36 vs 3255.2 ± 976.5, P < 0.0001) between the RIRS and mini-PCNL groups. The mean operation time was not significantly different between the RIRS group(56.48 ± 24.77) and the mini-PCNL group(60.04 ± 30.38, P = 0.345). The stone-free rates at the first postoperative day(RIRS vs mini-PCNL: 90.2% vs 93.2%, P = 0.822) and the second month postoperatively(RIRS vs mini-PCNL: 93.8% vs 95.1%, P = 0.986) were not significantly different.CONCLUSION RIRS and mini-PCNL are both safe and effective methods for treating LP stones with a diameter of 1.5-2.5 cm. RIRS can be considered as an alternative to PCNL for the treatment for LP stones of 1.5-2.5 cm.展开更多
Inertial piezoelectric actuators are widely applied in precision devices with simple structure and accurate movement.However,existing inertial piezoelectric actuators still face the challenges of rollback motion and b...Inertial piezoelectric actuators are widely applied in precision devices with simple structure and accurate movement.However,existing inertial piezoelectric actuators still face the challenges of rollback motion and bulky power supply.In this work,an alternate excitation strategy and a customized small power supply for a bimorph rotary piezoelectric actuator(BRPA)are proposed to solve the problems.The BRPA prototype is designed with a bipedal symmetrical structure,measuring 35 mm in height and 32 mm in diameter,which has a maximum rotation velocity of 0.247 rad/s and a resolution of 0.66μrad.Thanks to the bipedal symmetrical structure,the friction directions between the driving feet and the rotor can be coordinated to suppress the rollback.The rollback ratio is almost zero when the phase difference of the exciting signal is set as 180°.The customized power supply is designed and manufactured,whose size is 58 mm×56 mm×46 mm.It can output signals for the single step mode and the continuous mode,and they are adopted to excite BRPA to achieve a small stroke with one single step and a large stroke with continuous step,respectively.Then,an experimental system for optical fiber alignment is developed based on the BRPA and the customized small power supply,the experiment has verified the practicability of this work in the precision fields,especially in the miniaturized precision systems.展开更多
The rapid progress of micro/nanoelectronic systems and miniaturized portable devices has tremendously increased the urgent demands for miniaturized and integrated power supplies.Miniaturized energy storage devices(MES...The rapid progress of micro/nanoelectronic systems and miniaturized portable devices has tremendously increased the urgent demands for miniaturized and integrated power supplies.Miniaturized energy storage devices(MESDs),with their excellent properties and additional intelligent functions,are considered to be the preferable energy supplies for uninterrupted powering of microsystems.In this review,we aim to provide a comprehensive overview of the background,fundamentals,device configurations,manufacturing processes,and typical applications of MESDs,including their recent advances.Particular attention is paid to advanced device configurations,such as two-dimensional(2D)stacked,2D planar interdigital,2D arbitrary-shaped,three-dimensional planar,and wire-shaped structures,and their corresponding manufacturing strategies,such as printing,scribing,and masking techniques.Additionally,recent developments in MESDs,including microbatteries and microsupercapacitors,as well as microhybrid metal ion capacitors,are systematically summarized.A series of on-chip microsystems,created by integrating functional MESDs,are also highlighted.Finally,the remaining challenges and future research scope on MESDs are discussed.展开更多
Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics device.Understanding the ignition enhancement m...Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics device.Understanding the ignition enhancement mechanism of RMFs on semiconductor bridge(SCB)during the ignition process is crucial for the engineering and practical application of advanced initiator and pyrotechnics devices.In this study,a one-dimensional(1D)gas-solid two-phase flow ignition model was established to study the ignition process of ESCB to charge particles based on the reactivity of Al/MoO_(3) RMFs.In order to fully consider the coupled exothermic between the RMFs and the SCB plasma during the ignition process,the heat release of chemical reaction in RMFs was used as an internal heat source in this model.It is found that the exothermal reaction in RMFs improved the ignition performance of SCB.In the process of plasma rapid condensation with heat release,the product of RMFs enhanced the heat transfer process between the gas phase and the solid charge particle,which accelerated the expansion of hot plasma,and heated the solid charge particle as well as gas phase region with low temperature.In addition,it made up for pressure loss in the gas phase.During the plasma dissipation process,the exothermal chemical reaction in RMFs acted as the main heating source to heat the charge particle,making the surface temperature of the charge particle,gas pressure,and gas temperature rise continuously.This result may yield significant advantages in providing a universal ignition model for miniaturized ignition devices.展开更多
基金Supported by the Ningbo Medical Science and Technology Project,No.2014A33
文摘AIM To compare the outcomes of retrograde intrarenal surgery(RIRS) and miniaturized percutaneous nephrolithotomy(mini-PCNL) in treating lower pole(LP) renal stones with a diameter of 1.5-2.5 cm.METHODS A total of 216 patients who underwent mini-PCNL(n = 103) or RIRS n = 113) for LP stones with a diameter of 1.5-2.5 cm were enrolled between December 2015 and April 2017 at the Urology Department of Ningbo Urology and Nephrology Hospital.RESULTS Significant differences were found in the hospital stay(9.39 ± 4.01 vs 14.08 ± 5.26, P < 0.0001) and hospitalization costs(2624.5 ± 513.36 vs 3255.2 ± 976.5, P < 0.0001) between the RIRS and mini-PCNL groups. The mean operation time was not significantly different between the RIRS group(56.48 ± 24.77) and the mini-PCNL group(60.04 ± 30.38, P = 0.345). The stone-free rates at the first postoperative day(RIRS vs mini-PCNL: 90.2% vs 93.2%, P = 0.822) and the second month postoperatively(RIRS vs mini-PCNL: 93.8% vs 95.1%, P = 0.986) were not significantly different.CONCLUSION RIRS and mini-PCNL are both safe and effective methods for treating LP stones with a diameter of 1.5-2.5 cm. RIRS can be considered as an alternative to PCNL for the treatment for LP stones of 1.5-2.5 cm.
基金supported by the National Natural Science Foundation of China(Grant Nos.52105015 and 52225501)the China Postdoctoral Science Foundation(Grant No.2021M690830)the Postdoctoral Science Foundation of Heilongjiang Province,China(Grant No.LBH-Z21018)。
文摘Inertial piezoelectric actuators are widely applied in precision devices with simple structure and accurate movement.However,existing inertial piezoelectric actuators still face the challenges of rollback motion and bulky power supply.In this work,an alternate excitation strategy and a customized small power supply for a bimorph rotary piezoelectric actuator(BRPA)are proposed to solve the problems.The BRPA prototype is designed with a bipedal symmetrical structure,measuring 35 mm in height and 32 mm in diameter,which has a maximum rotation velocity of 0.247 rad/s and a resolution of 0.66μrad.Thanks to the bipedal symmetrical structure,the friction directions between the driving feet and the rotor can be coordinated to suppress the rollback.The rollback ratio is almost zero when the phase difference of the exciting signal is set as 180°.The customized power supply is designed and manufactured,whose size is 58 mm×56 mm×46 mm.It can output signals for the single step mode and the continuous mode,and they are adopted to excite BRPA to achieve a small stroke with one single step and a large stroke with continuous step,respectively.Then,an experimental system for optical fiber alignment is developed based on the BRPA and the customized small power supply,the experiment has verified the practicability of this work in the precision fields,especially in the miniaturized precision systems.
基金the financial support from the National Natural Science Foundation of China(Grant Nos.51702095,51722503,51975204)Natural Science Foundation of Hunan Province,China(Grant No.2018JJ3041)+1 种基金the Fundamental Research Funds for the Central Universities(531118010016)Science and Technology Bureau Foundation of Changsha City(kh1904005)。
文摘The rapid progress of micro/nanoelectronic systems and miniaturized portable devices has tremendously increased the urgent demands for miniaturized and integrated power supplies.Miniaturized energy storage devices(MESDs),with their excellent properties and additional intelligent functions,are considered to be the preferable energy supplies for uninterrupted powering of microsystems.In this review,we aim to provide a comprehensive overview of the background,fundamentals,device configurations,manufacturing processes,and typical applications of MESDs,including their recent advances.Particular attention is paid to advanced device configurations,such as two-dimensional(2D)stacked,2D planar interdigital,2D arbitrary-shaped,three-dimensional planar,and wire-shaped structures,and their corresponding manufacturing strategies,such as printing,scribing,and masking techniques.Additionally,recent developments in MESDs,including microbatteries and microsupercapacitors,as well as microhybrid metal ion capacitors,are systematically summarized.A series of on-chip microsystems,created by integrating functional MESDs,are also highlighted.Finally,the remaining challenges and future research scope on MESDs are discussed.
基金supported by the National Natural Science Foundation of China(Grant Nos.22275092,52102107 and 52372084)the Fundamental Research Funds for the Central Universities(Grant No.30923010920)。
文摘Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics device.Understanding the ignition enhancement mechanism of RMFs on semiconductor bridge(SCB)during the ignition process is crucial for the engineering and practical application of advanced initiator and pyrotechnics devices.In this study,a one-dimensional(1D)gas-solid two-phase flow ignition model was established to study the ignition process of ESCB to charge particles based on the reactivity of Al/MoO_(3) RMFs.In order to fully consider the coupled exothermic between the RMFs and the SCB plasma during the ignition process,the heat release of chemical reaction in RMFs was used as an internal heat source in this model.It is found that the exothermal reaction in RMFs improved the ignition performance of SCB.In the process of plasma rapid condensation with heat release,the product of RMFs enhanced the heat transfer process between the gas phase and the solid charge particle,which accelerated the expansion of hot plasma,and heated the solid charge particle as well as gas phase region with low temperature.In addition,it made up for pressure loss in the gas phase.During the plasma dissipation process,the exothermal chemical reaction in RMFs acted as the main heating source to heat the charge particle,making the surface temperature of the charge particle,gas pressure,and gas temperature rise continuously.This result may yield significant advantages in providing a universal ignition model for miniaturized ignition devices.
