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CLINICAL STUDY ON LASER NEEDLE-KNIFE AND ACUPUNCTURE FOR VERTEBRAL-ARTERY-TYPE CERVICAL SPONDYLOSIS
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作者 雷胜龙 覃天 《World Journal of Acupuncture-Moxibustion》 2007年第3期9-12,共4页
Objective To compare the effect of laser needle-knife and acupuncture with medication for vertebral-artery-type cervical spondylosis (CSA). Methods The 88 outpatients of CSA were divided with single-blind method int... Objective To compare the effect of laser needle-knife and acupuncture with medication for vertebral-artery-type cervical spondylosis (CSA). Methods The 88 outpatients of CSA were divided with single-blind method into Treatment Group (treated by laser needle-knife and acupuncture) with 48 patients in it and Control Group (treated by Intravenous drip of Compound Salvia Miltiorrhiza Injection and oral taking of Flunarizine (Sibelium) with 40 patients in it. Before the treatment, the two groups were without difference statistically. Results In the treatment group, the curative rate was 60.42% and the total effective rate 97.92%. In the control group, the curative rate was 30% and the total effective rate 87.5%. In statistics, P〈0.05, a significant difference existed between the two groups. Conclusion The effect of laser needleknife and acupuncture for CSA is obviously better than that of medication, worth spreading. 展开更多
关键词 laser needle-knife Acupuncture Vertebral-artery-type cervical spondylosis (CSA)Single-blind method
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Application of needle-knife in difficult biliary cannulation for endoscopic retrograde cholangiopancreatography 被引量:16
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作者 Ping-Hong Zhou, Li-Qing Yao, Mei-Dong Xu, Yun-Shi Zhong, Wei-Dong Gao, Guo-Jie He, Yi-Qun Zhang, Wei-Feng Chen and Xin-Yu Qin Department of General Surgery, Zhongshan Hospital, Fudan University, Shanghai 200032, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2006年第4期590-594,共5页
BACKGROUND: Getting directly into the common bile duct (CBD) is the most important step for successful therapeutic biliary endoscopy. In 5%-10% of cases, the CBD remains inaccessible, necessitating pre-cut papillotomy... BACKGROUND: Getting directly into the common bile duct (CBD) is the most important step for successful therapeutic biliary endoscopy. In 5%-10% of cases, the CBD remains inaccessible, necessitating pre-cut papillotomy or fistulotomy with a needle-knife. The aim of this study was to assess the value of early application of the needle-knife in difficult biliary cannulation for endoscopic retrograde cholangiopancreatography (ERCP). METHODS: Patients with failed biliary cannulation after 10 minutes or guide wire entering the pancreatic tube 3 times were randomly divided into group of needle-knife cut and group of persistent cannulation by standard techniques. The cannulation times, success rates and complication rates were compared between the two groups. RESULTS: A total of 948 therapeutic biliary ERCP procedures were performed between October 2004 and February 2006. Of 91 patients with difficult biliary cannulation, 43 patients underwent needle-knife cut: the cannulation success rate was 90.7%, the mean cannulation time was 5.6 minutes, and the complication rate was 9.3%. The other 48 patients underwent persistent cannulation by standard techniques: the cannulation success rate was 75%, the mean cannulation time was 10.2 minutes, and the complication rate was 14.6%. Significant differences were observed in cannulation success rate and cannulation time but in complication rate between the two groups.CONCLUSION: The early application of the needle-knife in difficult biliary cannulation is time-saving, safe and effective, with no increase in complication rate. 展开更多
关键词 endoscopic retrograde cholangiopancreatography needle-knife CANNULATION
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Comparison of efficacy and safety of transpancreatic septotomy, needle-knife fistulotomy or both based on biliary cannulation unintentional pancreatic access and papillary morphology 被引量:11
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作者 Jun Wen Tao Li +2 位作者 Yi Lu Li-Ke Bie Biao Gong 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2019年第1期73-78,共6页
Background: Precut sphincterotomy has been widely performed to facilitate selective biliary access when standard cannulation attempts failed during endoscopic retrograde cholangiopancreatography(ERCP). However, scarce... Background: Precut sphincterotomy has been widely performed to facilitate selective biliary access when standard cannulation attempts failed during endoscopic retrograde cholangiopancreatography(ERCP). However, scarce data are available on different precut techniques for difficult biliary cannulation. This study aimed to evaluate the efficacy and safety of transpancreatic septotomy(TPS), needle-knife fistulotomy(NKF) or both based on the presence of unintentional pancreatic access and papillary morphology. Methods: Between March 2008 and December 2016, 157 consecutive patients undergoing precutting for an inaccessible bile duct during ERCP were identified. Precut techniques were chosen depending on repetitive inadvertent pancreatic cannulation and the papillary morphology. We retrospectively assessed the rates of cannulation success and procedure-related complications among three groups, namely TPS, NKF, and TPS followed by NKF. Results: The baseline characteristics of the three groups were comparable. The overall success rate of biliary cannulation reached 98.1%, including 111 of 113(98.2%) with TPS, 35 of 36(97.2%) with NKF and 8 of 8(100%) with NKF following TPS, without significant difference among groups. The incidences of total complications and post-ERCP pancreatitis were 9.6% and 7.6%, respectively. There was a trend towards less frequent post-ERCP pancreatitis after NKF(0%) compared with 11 cases(9.7%) after TPS and one case(12.5%) after NKF following TPS, but not significantly different( P = 0.07). No severe adverse event occurred during this study period. Conclusions: The choice of precut techniques by the presence of unintended pancreatic access and the papillary morphology brought about a high success rate without increasing risk in difficult biliary cannulation. 展开更多
关键词 Difficult BILIARY CANNULATION Endoscopic retrograde cholangiopancreatography needle-knife FISTULOTOMY PRECUT techniques Transpancreatic septotomy
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Endoscopic treatment for pancreatic diseases:Needle-knife-guided cannulation via the minor papilla 被引量:2
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作者 Wei Wang Biao Gong +4 位作者 Wei-Song Jiang Lei Liu Kouken Bielike Bin Xv Yun-Lin Wu 《World Journal of Gastroenterology》 SCIE CAS 2015年第19期5950-5960,共11页
AIM: To determine the efficacy and safety of meticulous cannulation by needle-knife.METHODS: Three needle-knife procedures were used to facilitate cannulation in cases when standard cannulation techniques failed. A to... AIM: To determine the efficacy and safety of meticulous cannulation by needle-knife.METHODS: Three needle-knife procedures were used to facilitate cannulation in cases when standard cannulation techniques failed. A total of 104 cannulationsvia the minor papilla attempted in 74 patients at our center between January 2008 and June 2014 were retrospectively reviewed.RESULTS: Standard methods were successful in79 cannulations. Of the 25 cannulations that could not be performed by standard methods, 19 were performed by needle-knife, while 17(89.5%) were successful. Needle-knife use improved the success rate of cannulation [76.0%, 79/104 vs 92.3%,(79 +17)/104; P = 0.001]. When the 6 cases not appropriate for needle-knife cannulation were excluded, the success rate was improved further(80.6%, 79/98 vs98.0%, 96/98; P = 0.000). There were no significant differences in the rates of post-endoscopic retrograde cholangiopancreatography adverse events between the group using standard methods alone and the group using needle-knife after failure of standard methods(4.7% vs 10.5%, P = 0.301).CONCLUSION: The needle-knife procedure may be an alternative method for improving the success rate of cannulation via the minor papilla, particularly when standard cannulation has failed. 展开更多
关键词 needle-knife MINOR PAPILLA CANNULATION Meticulous procedure Endoscopic retrograde CHOLANGIOPANCREATOGRAPHY
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Underwater four-quadrant dual-beam circumferential scanning laser fuze using nonlinear adaptive backscatter filter based on pauseable SAF-LMS algorithm 被引量:2
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作者 Guangbo Xu Bingting Zha +2 位作者 Hailu Yuan Zhen Zheng He Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第7期1-13,共13页
The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly undermines the detection range and precision of underwater laser fuzes.To overcome this issue,we propose a four-quadrant ... The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly undermines the detection range and precision of underwater laser fuzes.To overcome this issue,we propose a four-quadrant dual-beam circumferential scanning laser fuze to distinguish various interference signals and provide more real-time data for the backscatter filtering algorithm.This enhances the algorithm loading capability of the fuze.In order to address the problem of insufficient filtering capacity in existing linear backscatter filtering algorithms,we develop a nonlinear backscattering adaptive filter based on the spline adaptive filter least mean square(SAF-LMS)algorithm.We also designed an algorithm pause module to retain the original trend of the target echo peak,improving the time discrimination accuracy and anti-interference capability of the fuze.Finally,experiments are conducted with varying signal-to-noise ratios of the original underwater target echo signals.The experimental results show that the average signal-to-noise ratio before and after filtering can be improved by more than31 d B,with an increase of up to 76%in extreme detection distance. 展开更多
关键词 laser fuze Underwater laser detection Backscatter adaptive filter Spline least mean square algorithm Nonlinear filtering algorithm
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Alloy design for laser powder bed fusion additive manufacturing:a critical review 被引量:3
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作者 Zhuangzhuang Liu Qihang Zhou +4 位作者 Xiaokang Liang Xiebin Wang Guichuan Li Kim Vanmeensel Jianxin Xie 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期29-63,共35页
Metal additive manufacturing(AM)has been extensively studied in recent decades.Despite the significant progress achieved in manufacturing complex shapes and structures,challenges such as severe cracking when using exi... Metal additive manufacturing(AM)has been extensively studied in recent decades.Despite the significant progress achieved in manufacturing complex shapes and structures,challenges such as severe cracking when using existing alloys for laser powder bed fusion(L-PBF)AM have persisted.These challenges arise because commercial alloys are primarily designed for conventional casting or forging processes,overlooking the fast cooling rates,steep temperature gradients and multiple thermal cycles of L-PBF.To address this,there is an urgent need to develop novel alloys specifically tailored for L-PBF technologies.This review provides a comprehensive summary of the strategies employed in alloy design for L-PBF.It aims to guide future research on designing novel alloys dedicated to L-PBF instead of adapting existing alloys.The review begins by discussing the features of the L-PBF processes,focusing on rapid solidification and intrinsic heat treatment.Next,the printability of the four main existing alloys(Fe-,Ni-,Al-and Ti-based alloys)is critically assessed,with a comparison of their conventional weldability.It was found that the weldability criteria are not always applicable in estimating printability.Furthermore,the review presents recent advances in alloy development and associated strategies,categorizing them into crack mitigation-oriented,microstructure manipulation-oriented and machine learning-assisted approaches.Lastly,an outlook and suggestions are given to highlight the issues that need to be addressed in future work. 展开更多
关键词 laser powder bed fusion alloy design PRINTABILITY crack mitigation
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Laser‑Induced and MOF‑Derived Metal Oxide/Carbon Composite for Synergistically Improved Ethanol Sensing at Room temperature 被引量:2
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作者 Hyeongtae Lim Hyeokjin Kwon +2 位作者 Hongki Kang Jae Eun Jang Hyuk‑Jun Kwon 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期210-220,共11页
Advancements in sensor technology have significantly enhanced atmospheric monitoring.Notably,metal oxide and carbon(MO_(x)/C)hybrids have gained attention for their exceptional sensitivity and room-temperature sensing... Advancements in sensor technology have significantly enhanced atmospheric monitoring.Notably,metal oxide and carbon(MO_(x)/C)hybrids have gained attention for their exceptional sensitivity and room-temperature sensing performance.However,previous methods of synthesizing MO_(x)/C composites suffer from problems,including inhomogeneity,aggregation,and challenges in micropatterning.Herein,we introduce a refined method that employs a metal–organic framework(MOF)as a precursor combined with direct laser writing.The inherent structure of MOFs ensures a uniform distribution of metal ions and organic linkers,yielding homogeneous MO_(x)/C structures.The laser processing facilitates precise micropatterning(<2μm,comparable to typical photolithography)of the MO_(x)/C crystals.The optimized MOF-derived MO_(x)/C sensor rapidly detected ethanol gas even at room temperature(105 and 18 s for response and recovery,respectively),with a broad range of sensing performance from 170 to 3,400 ppm and a high response value of up to 3,500%.Additionally,this sensor exhibited enhanced stability and thermal resilience compared to previous MOF-based counterparts.This research opens up promising avenues for practical applications in MOF-derived sensing devices. 展开更多
关键词 Metal-organic frameworks Metal oxide Carbon composite laser Gas sensor
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Primary needle-knife fistulotomy for preventing post-endoscopic retrograde cholangiopancreatography pancreatitis:Importance of the endoscopist’s expertise level
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作者 Sung Yong Han Dong Hoon Baek +4 位作者 Dong Uk Kim Chang Joon Park Young Joo Park Moon Won Lee Geun Am Song 《World Journal of Clinical Cases》 SCIE 2021年第17期4166-4177,共12页
BACKGROUND Needle-knife fistulotomy(NKF)is used as a rescue technique for difficult cannulation.However,the data are limited regarding the use of NKF for primary biliary cannulation,especially when performed by beginn... BACKGROUND Needle-knife fistulotomy(NKF)is used as a rescue technique for difficult cannulation.However,the data are limited regarding the use of NKF for primary biliary cannulation,especially when performed by beginners.AIM To assess the effectiveness and safety of primary NKF for biliary cannulation,and the role of the endoscopist’s expertise level(beginner vs expert).METHODS We retrospectively evaluated the records of 542 patients with naïve prominent bulging papilla and no history of pancreatitis,who underwent bile duct cannulation at a tertiary referral center.The patients were categorized according to the endoscopist’s expertise level and the technique used for bile duct cannulation.We assessed the rates of successful cannulation and adverse events.RESULTS The baseline characteristics did not differ between the experienced and lessexperienced endoscopists.The incidence rate of post-endoscopic retrograde cholangiopancreatography(ERCP)pancreatitis(PEP)was significantly affected by the endoscopist’s expertise level in patients who received conventional cannulation with sphincterotomy(8.9%vs 3.4%for beginner vs expert,P=0.039),but not in those who received NKF.In the multivariable analysis,a lower expertise level of the biliary endoscopist(P=0.037)and longer total procedure time(P=0.026)were significant risk factor of PEP in patients who received conventional cannulation with sphincterotomy but only total procedure time(P=0.004)was significant risk factor of PEP in those who received NKF.CONCLUSION Primary NKF was effective and safe in patients with prominent and bulging ampulla,even when performed by less-experienced endoscopist.We need to confirm which level of endoscopist’s experience is needed for primary NKF through prospective randomized study. 展开更多
关键词 needle-knife fistulotomy Primary biliary cannulation Endoscopic retrograde cholangiopancreatography Expertise levels PANCREATITIS
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Backward scattering of laser plasma interactions from hundreds-of-joules broadband laser on thick target 被引量:1
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作者 Peipei Wang Honghai An +14 位作者 Zhiheng Fang Jun Xiong Zhiyong Xie Chen Wang Zhiyu He Guo Jia Ruirong Wang Shu Zheng Lan Xia Wei Feng Haitao Shi Wei Wang Jinren Sun Yanqi Gao Sizu Fu 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第1期5-14,共10页
The use of broadband laser technology is a novel approach for inhibiting processes related to laser plasma interactions(LPIs).In this study,several preliminary experiments into broadband-laser-driven LPIs are carried ... The use of broadband laser technology is a novel approach for inhibiting processes related to laser plasma interactions(LPIs).In this study,several preliminary experiments into broadband-laser-driven LPIs are carried out using a newly established hundreds-of-joules broadband second-harmonic-generation laser facility.Through direct comparison with LPI results for a traditional narrowband laser,the actual LPI-suppression effect of the broadband laser is shown.The broadband laser had a clear suppressive effect on both back-stimulated Raman scattering and back-stimulated Brillouin scattering at laser intensities below 1×10^(15) W cm^(−2).An abnormal hot-electron phenomenon is also investigated,using targets of different thicknesses. 展开更多
关键词 SCATTERING laser hundreds
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Characterization, preparation, and reuse of metallic powders for laser powder bed fusion: a review 被引量:2
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作者 Xiaoyu Sun Minan Chen +4 位作者 Tingting Liu Kai Zhang Huiliang Wei Zhiguang Zhu Wenhe Liao 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期52-91,共40页
Laser powder bed fusion(L-PBF) has attracted significant attention in both the industry and academic fields since its inception, providing unprecedented advantages to fabricate complex-shaped metallic components. The ... Laser powder bed fusion(L-PBF) has attracted significant attention in both the industry and academic fields since its inception, providing unprecedented advantages to fabricate complex-shaped metallic components. The printing quality and performance of L-PBF alloys are infuenced by numerous variables consisting of feedstock powders, manufacturing process,and post-treatment. As the starting materials, metallic powders play a critical role in infuencing the fabrication cost, printing consistency, and properties. Given their deterministic roles, the present review aims to retrospect the recent progress on metallic powders for L-PBF including characterization, preparation, and reuse. The powder characterization mainly serves for printing consistency while powder preparation and reuse are introduced to reduce the fabrication costs.Various powder characterization and preparation methods are presented in the beginning by analyzing the measurement principles, advantages, and limitations. Subsequently, the effect of powder reuse on the powder characteristics and mechanical performance of L-PBF parts is analyzed, focusing on steels, nickel-based superalloys, titanium and titanium alloys, and aluminum alloys. The evolution trends of powders and L-PBF parts vary depending on specific alloy systems, which makes the proposal of a unified reuse protocol infeasible. Finally,perspectives are presented to cater to the increased applications of L-PBF technologies for future investigations. The present state-of-the-art work can pave the way for the broad industrial applications of L-PBF by enhancing printing consistency and reducing the total costs from the perspective of powders. 展开更多
关键词 laser powder bed fusion powder characterization powder preparation powder reuse
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Triboelectric‘electrostatic tweezers'for manipulating droplets on lubricated slippery surfaces prepared by femtosecond laser processing 被引量:2
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作者 Jiale Yong Xinlei Li +5 位作者 Youdi Hu Yubin Peng Zilong Cheng Tianyu Xu Chaowei Wang Dong Wu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期411-426,共16页
The use of‘Electrostatic tweezers'is a promising tool for droplet manipulation,but it faces many limitations in manipulating droplets on superhydrophobic surfaces.Here,we achieve noncontact and multifunctional dr... The use of‘Electrostatic tweezers'is a promising tool for droplet manipulation,but it faces many limitations in manipulating droplets on superhydrophobic surfaces.Here,we achieve noncontact and multifunctional droplet manipulation on Nepenthes-inspired lubricated slippery surfaces via triboelectric electrostatic tweezers(TETs).The TET manipulation of droplets on a slippery surface has many advantages over electrostatic droplet manipulation on a superhydrophobic surface.The electrostatic field induces the redistribution of the charges inside the neutral droplet,which causes the triboelectric charged rod to drive the droplet to move forward under the electrostatic force.Positively or negatively charged droplets can also be driven by TET based on electrostatic attraction and repulsion.TET enables us to manipulate droplets under diverse conditions,including anti-gravity climb,suspended droplets,corrosive liquids,low-surface-tension liquids(e.g.ethanol with a surface tension of 22.3 mN·m^(-1)),different droplet volumes(from 100 nl to 0.5 ml),passing through narrow slits,sliding over damaged areas,on various solid substrates,and even droplets in an enclosed system.Various droplet-related applications,such as motion guidance,motion switching,droplet-based microreactions,surface cleaning,surface defogging,liquid sorting,and cell labeling,can be easily achieved with TETs. 展开更多
关键词 triboelectric electrostatic tweezer droplet manipulation slippery surface superhydrophobic surface femtosecond laser
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Laser spectroscopy imaging technique coupled withnanomaterials for cancer diagnosis: A review 被引量:1
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作者 Zhengying Peng Pengkun Yin +5 位作者 Dan Li Youyuan Chen Kaiqiang Shu Qingwen Fan Yixiang Duan Qingyu Lin 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第1期1-27,共27页
Laser spectroscopic imaging techniques have received tremendous attention in the-eld of cancer diagnosis due to their high sensitivity,high temporal resolution,and short acquisition time.However,the limited tissue pen... Laser spectroscopic imaging techniques have received tremendous attention in the-eld of cancer diagnosis due to their high sensitivity,high temporal resolution,and short acquisition time.However,the limited tissue penetration of the laser is still a challenge for the in vivo diagnosis of deep-seated lesions.Nanomaterials have been universally integrated with spectroscopic imaging techniques for deeper cancer diagnosis in vivo.The components,morphology,and sizes of nanomaterials are delicately designed,which could realize cancer diagnosis in vivo or in situ.Considering the enhanced signal emitting from the nanomaterials,we emphasized their combination with spectroscopic imaging techniques for cancer diagnosis,like the surface-enhanced Raman scattering(SERS),photoacoustic,fluorescence,and laser-induced breakdown spectroscopy(LIBS).Applications ofthe above spectroscopic techniques offer new prospectsfor cancer diagnosis. 展开更多
关键词 laser spectroscopy tumor imaging tumor diagnosis NANOMATERIALS
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High-performance liquid metal electromagnetic actuator fabricated by femtosecond laser 被引量:1
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作者 Yiyu Chen Hao Wu +11 位作者 Rui Li Shaojun Jiang Shuneng Zhou Zehang Cui Yuan Tao Xinyuan Zheng Qianqian Zhang Jiawen Li Guoqiang Li Dong Wu Jiaru Chu Yanlei Hu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期511-521,共11页
Small-scale electromagnetic soft actuators are characterized by a fast response and simplecontrol,holding prospects in the field of soft and miniaturized robotics.The use of liquid metal(LM)to replace a rigid conducto... Small-scale electromagnetic soft actuators are characterized by a fast response and simplecontrol,holding prospects in the field of soft and miniaturized robotics.The use of liquid metal(LM)to replace a rigid conductor inside soft actuators can reduce the rigidity and enhance the actuation performance and robustness.Despite research efforts,challenges persist in the flexible fabrication of LM soft actuators and in the improvement of actuation performance.To address these challenges,we developed a fast and robust electromagnetic soft microplate actuator based on a laser-induced selective adhesion transfer method.Equipped with unprecedentedly thin LM circuit and customized low Young’s modulus silicone rubber(1.03 kPa),our actuator exhibits an excellent deformation angle(265.25?)and actuation bending angular velocity(284.66 rad·s^(-1)).Furthermore,multiple actuators have been combined to build an artificial gripper with a wide range of functionalities.Our actuator presents new possibilities for designing small-scaleartificial machines and supports advancements in ultrafast soft and miniaturized robotics. 展开更多
关键词 soft actuators femtosecond laser liquid metal
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Influence of layer thickness on formation quality,microstructure,mechanical properties,and corrosion resistance of WE43 magnesium alloy fabricated by laser powder bed fusion 被引量:2
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作者 Bangzhao Yin Jinge Liu +7 位作者 Bo Peng Mengran Zhou Bingchuan Liu Xiaolin Ma Caimei Wang Peng Wen Yun Tian Yufeng Zheng 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1367-1385,共19页
Laser powder bed fusion(L-PBF)of Mg alloys has provided tremendous opportunities for customized production of aeronautical and medical parts.Layer thickness(LT)is of great significance to the L-PBF process but has not... Laser powder bed fusion(L-PBF)of Mg alloys has provided tremendous opportunities for customized production of aeronautical and medical parts.Layer thickness(LT)is of great significance to the L-PBF process but has not been studied for Mg alloys.In this study,WE43 Mg alloy bulk cubes,porous scaffolds,and thin walls with layer thicknesses of 10,20,30,and 40μm were fabricated.The required laser energy input increased with increasing layer thickness and was different for the bulk cubes and porous scaffolds.Porosity tended to occur at the connection joints in porous scaffolds for LT40 and could be eliminated by reducing the laser energy input.For thin wall parts,a large overhang angle or a small wall thickness resulted in porosity when a large layer thicknesses was used,and the porosity disappeared by reducing the layer thickness or laser energy input.A deeper keyhole penetration was found in all occasions with porosity,explaining the influence of layer thickness,geometrical structure,and laser energy input on the porosity.All the samples achieved a high fusion quality with a relative density of over 99.5%using the optimized laser energy input.The increased layer thickness resulted to more precipitation phases,finer grain sizes and decreased grain texture.With the similar high fusion quality,the tensile strength and elongation of bulk samples were significantly improved from 257 MPa and 1.41%with the 10μm layer to 287 MPa and 15.12%with the 40μm layer,in accordance with the microstructural change.The effect of layer thickness on the compressive properties of porous scaffolds was limited.However,the corrosion rate of bulk samples accelerated with increasing the layer thickness,mainly attributed to the increased number of precipitation phases. 展开更多
关键词 Magnesium alloy WE43 laser powder bed fusion Layer thickness Process optimization
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Diagnosis of poorly differentiated adenocarcinoma of the stomach by confocal laser endomicroscopy:A case report 被引量:3
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作者 Jia-Xin Lou Yong Wu +3 位作者 Muren Huhe Jing-Jie Zhang Dong-Wu Jia Zhen-Yu Jiang 《World Journal of Clinical Cases》 SCIE 2024年第8期1481-1486,共6页
BACKGROUND In recent years,confocal laser endomicroscopy(CLE)has become a new endoscopic imaging technology at the microscopic level,which is extensively performed for real-time in vivo histological examination.CLE ca... BACKGROUND In recent years,confocal laser endomicroscopy(CLE)has become a new endoscopic imaging technology at the microscopic level,which is extensively performed for real-time in vivo histological examination.CLE can be performed to distinguish benign from malignant lesions.In this study,we diagnosed using CLE an asymptomatic patient with poorly differentiated gastric adenocarcinoma.CASE SUMMARY A 63-year-old woman was diagnosed with gastric mucosal lesions,which may be gastric cancer,in the small curvature of the stomach by gastroscopy.She consented to undergo CLE for morphological observation of the gastric mucosa.Through the combination of CLE diagnosis and postoperative pathology,the intraoperative CLE diagnosis was considered to be reliable.According to our experience,CLE can be performed as the first choice for the diagnosis of gastric cancer.CONCLUSION CLE has several advantages over pathological diagnosis.We believe that CLE has great potential in the diagnosis of benign and malignant gastric lesions. 展开更多
关键词 Confocal laser endomicroscopy Poorly differentiated gastric adenocarcinoma DIAGNOSIS Early stage Case report
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Mechanical and damping performances of TPMS lattice metamaterials fabricated by laser powder bed fusion 被引量:1
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作者 Yan-peng Wei Huai-qian Li +7 位作者 Jing-jing Han Ying-chun Ma Hao-ran Zhou Jing-chang Cheng Jian Shi Zhi-quan Miao Bo Yu Feng Lin 《China Foundry》 SCIE EI CAS CSCD 2024年第4期327-333,共7页
Lattice metamaterials based on three-period minimum surface(TPMS)are an effective means to achieve lightweight and high-strength materials which are widely used in various fields such as aerospace and ships.However,it... Lattice metamaterials based on three-period minimum surface(TPMS)are an effective means to achieve lightweight and high-strength materials which are widely used in various fields such as aerospace and ships.However,its vibration and noise reduction,and damping properties have not been fully studied.Therefore,in this study,the TPMS structures with parameterization were designed by the method of surface migration,and the TPMS structures with high forming quality was manufactured by laser powder bed fusion(LPBF).The mechanical properties and energy absorption characteristics of the beam and TPMS structures were studied and compared by quasi-static compression.The modal shapes of the beam lattice structures and TPMS structures were obtained by the free modal analysis,and the damping properties of two structures were obtained by modal tests.For the two structures after heat treatment with the same porosity of 70%,the yield strength of the beam lattice structure reaches 40.76 MPa,elastic modulus is 20.38 GPa,the energy absorption value is 32.23 MJ·m^(-3),the damping ratio is 0.52%.The yield strength,elastic modulus,energy absorption value,and damping ratio of the TPMS structure are 50.74 MPa,25.37 GPa,47.34 MJ·m^(-3),and 0.99%,respectively.The results show that TPMS structures exhibit more excellent mechanical properties and energy absorption,better damping performance,and obvious advantages in structural load and vibration and noise reduction compared with the beam lattice structures under the same porosity. 展开更多
关键词 lattice metamaterials TPMS energy absorption DAMPING laser powder bed fusion
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Recent developments in selective laser processes for wearable devices 被引量:1
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作者 Youngchan Kim Eunseung Hwang +3 位作者 Chang Kai Kaichen Xu Heng Pan Sukjoon Hong 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期517-547,共31页
Recently,the increasing interest in wearable technology for personal healthcare and smart virtual/augmented reality applications has led to the development of facile fabrication methods.Lasers have long been used to d... Recently,the increasing interest in wearable technology for personal healthcare and smart virtual/augmented reality applications has led to the development of facile fabrication methods.Lasers have long been used to develop original solutions to such challenging technological problems due to their remote,sterile,rapid,and site-selective processing of materials.In this review,recent developments in relevant laser processes are summarized under two separate categories.First,transformative approaches,such as for laser-induced graphene,are introduced.In addition to design optimization and the alteration of a native substrate,the latest advances under a transformative approach now enable more complex material compositions and multilayer device configurations through the simultaneous transformation of heterogeneous precursors,or the sequential addition of functional layers coupled with other electronic elements.In addition,the more conventional laser techniques,such as ablation,sintering,and synthesis,can still be used to enhance the functionality of an entire system through the expansion of applicable materials and the adoption of new mechanisms.Later,various wearable device components developed through the corresponding laser processes are discussed,with an emphasis on chemical/physical sensors and energy devices.In addition,special attention is given to applications that use multiple laser sources or processes,which lay the foundation for the all-laser fabrication of wearable devices. 展开更多
关键词 Selective laser process Wearable device Transformative approach laser-induced graphene Ablation SINTERING Synthesis
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Role of heterogenous microstructure and deformation behavior in achieving superior strength-ductility synergy in zinc fabricated via laser powder bed fusion 被引量:1
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作者 Zhi Dong Changjun Han +7 位作者 Yanzhe Zhao Jinmiao Huang Chenrong Ling Gaoling Hu Yunhui Wang Di Wang Changhui Song Yongqiang Yang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第4期225-245,共21页
Zinc(Zn)is considered a promising biodegradable metal for implant applications due to its appropriate degradability and favorable osteogenesis properties.In this work,laser powder bed fusion(LPBF)additive manufacturin... Zinc(Zn)is considered a promising biodegradable metal for implant applications due to its appropriate degradability and favorable osteogenesis properties.In this work,laser powder bed fusion(LPBF)additive manufacturing was employed to fabricate pure Zn with a heterogeneous microstructure and exceptional strength-ductility synergy.An optimized processing window of LPBF was established for printing Zn samples with relative densities greater than 99%using a laser power range of 80∼90 W and a scanning speed of 900 mm s−1.The Zn sample printed with a power of 80 W at a speed of 900 mm s−1 exhibited a hierarchical heterogeneous microstructure consisting of millimeter-scale molten pool boundaries,micrometer-scale bimodal grains,and nanometer-scale pre-existing dislocations,due to rapid cooling rates and significant thermal gradients formed in the molten pools.The printed sample exhibited the highest ductility of∼12.1%among all reported LPBF-printed pure Zn to date with appreciable ultimate tensile strength(∼128.7 MPa).Such superior strength-ductility synergy can be attributed to the presence of multiple deformation mechanisms that are primarily governed by heterogeneous deformation-induced hardening resulting from the alternative arrangement of bimodal Zn grains with pre-existing dislocations.Additionally,continuous strain hardening was facilitated through the interactions between deformation twins,grains and dislocations as strain accumulated,further contributing to the superior strength-ductility synergy.These findings provide valuable insights into the deformation behavior and mechanisms underlying exceptional mechanical properties of LPBF-printed Zn and its alloys for implant applications. 展开更多
关键词 laser powder bed fusion ZINC heterogeneous microstructure bimodal grains strength-ductility synergy
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Advances in needle-knife for the treatment of early and middle stage Osteonecrosis of the Femoral Head
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作者 Yan Yan Hai-Jun He 《Journal of Hainan Medical University》 2020年第1期63-67,共5页
Osteonecrosis of the Femoral Head (ONFH) is a refractory disease of orthopedics, and its incidence is gradually increasing. Often due to lack of timely intervention, the femoral head collapses, eventually causing hip ... Osteonecrosis of the Femoral Head (ONFH) is a refractory disease of orthopedics, and its incidence is gradually increasing. Often due to lack of timely intervention, the femoral head collapses, eventually causing hip pain and difficulty in activities. At present, the treatment of hip preservation after the collapse of osteonecrosis of the femoral head has received everyone's attention, but many hip-preserving measures are controversial in terms of efficacy and indications. Needle-knife therapy is a kind of hip-protection therapy with low risk, small trauma, bleeding, and less and shorter treatments. This article reviews the literatures related to needle-knife therapy for osteonecrosis of the femoral head, and summarizes the clinical treatment of osteonecrosis of the femoral head based on needle-knife, and prospects for its research. 展开更多
关键词 needle-knife OSTEONECROSIS of the FEMORAL Head Mechanism TREATMENT method Efficacy evaluation Review
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Eighty Cases of Heel Bone Spikes Treated With Little Needle-Knife
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作者 Xuan Jonghua(Outpatient Department of PLA No.181 Hospital,Guilin 541002) 《中国针灸》 CAS CSCD 北大核心 1995年第S2期295-295,共1页
EightyCasesofHeelBoneSpikesTreatedWithLittleNeedle-Knife¥XuanJonghua(OutpatientDepartmentofPLANo.181Hospital... EightyCasesofHeelBoneSpikesTreatedWithLittleNeedle-Knife¥XuanJonghua(OutpatientDepartmentofPLANo.181Hospital,Guilin541002)Hee... 展开更多
关键词 Eighty Cases of Heel Bone Spikes Treated With Little needle-knife
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