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Minimally manipulated autologous adherent bone marrow cells (ABMCs):a promising cell therapy of spinal cord injury 被引量:3
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作者 Kamana Misra Hatem E.Sabaawy 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第7期1058-1060,共3页
Spinal cord injury(SCI)is a devastating ailment that results in drastic life style alterations for the patients and their family members(Mc Donald and Sadowsky,2002).Damage post injury causes necrosis,edema,hemorr... Spinal cord injury(SCI)is a devastating ailment that results in drastic life style alterations for the patients and their family members(Mc Donald and Sadowsky,2002).Damage post injury causes necrosis,edema,hemorrhage and vasospasm.Post injury,secondary damage is caused by ischemia, 展开更多
关键词 BONE CELL Minimally manipulated autologous adherent bone marrow cells a promising cell therapy of spinal cord injury ABMCs MSCS
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基于Manipulate的数值分析交互式课件制作
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作者 段敏 谢进 《合肥学院学报(综合版)》 2020年第5期141-144,共4页
论述了信息技术与教育教学深度融合的现状,指出了制作课件是提高教师TPACK素养的方法之一,以Mathematica软件中的Manipulate函数为桥梁,给出了数值分析交互式课件制作的方法及即时制作的可能性。
关键词 TPACK manipulate 课件
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基于Manipulate的大学数学课件制作 被引量:1
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作者 段敏 《普洱学院学报》 2020年第6期29-31,共3页
数学课件制作难,难在于交互,自从Mathematica6版本中引入了Manipulate函数后,制作交互式图形用户界面的数学课件易如反掌。基于此,论述Manipulate函数制作大学数学课件的一般方法及注意事项。
关键词 manipulate 课件 控件
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Research & design on the drive system of nuclear fuel manipulate crane
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作者 穆兆辉 Li Weidong Liu Rao 《High Technology Letters》 EI CAS 2014年第4期446-450,共5页
The control of nuclear fuel manipulator crane (MC) drive system is essential for its running and other systems are designed surrounding the drive system.This paper gives a brief introduction to the composition and f... The control of nuclear fuel manipulator crane (MC) drive system is essential for its running and other systems are designed surrounding the drive system.This paper gives a brief introduction to the composition and function of MC,analyses its drive mode and control method and applies PLC to control its frequency transducer directly to help the motor work more stable.Based on the control requirements of bridge,trolley,Hoist,the control system of bridge applies a drive mode with 2-drag2 drive model on both sides and a multi-control method to realize simultaneous runningof two sides,1-drag-1 model on through-going axes and closed loop control method finish the precise location of trolley,and the using of 1-drag-1 model drive mode and closed loop control method solves the protect control difficulty of hoist which stops/starts repeatedly and changes speed. 展开更多
关键词 PMC manipulate crane (MC) drive system drive mode control method
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Alopecia treatment using minimally manipulated human umbilical cord-derived mesenchymal stem cells:Three case reports and review of literature 被引量:5
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作者 Hyunjun Ahn Sang Yeon Lee +1 位作者 Won Ju Jung Kye-Ho Lee 《World Journal of Clinical Cases》 SCIE 2021年第15期3741-3751,共11页
BACKGROUND Alopecia areata(AA)is a common autoimmune disease characterized by hair loss.AA appears in extensive forms,such as progressive and diffusing hair loss(diffuse AA),a total loss of scalp hair(alopecia totalis... BACKGROUND Alopecia areata(AA)is a common autoimmune disease characterized by hair loss.AA appears in extensive forms,such as progressive and diffusing hair loss(diffuse AA),a total loss of scalp hair(alopecia totalis),and complete loss of hair over the entire body(alopecia universalis).Recently,mesenchymal stem cells(MSCs)have been identified as a therapeutic alternative for autoimmune diseases.For this reason,preclinical and case studies of AA and related diseases using MSCs have been conducted.CASE SUMMARY Case 1:A 55-year-old woman suffered from AA in two areas of the scalp.She was given 15 rounds of minimally manipulated umbilical cord-MSCs(MM-UC-MSCs)over 6 mo.The AA gradually improved 3 mo after the first round.The patient was cured,and AA did not recur.Case 2:A 30-year-old woman,with history of local steroid hormone injections,suffered from AA in one area on the scalp.She was given two rounds of MM-UC-MSCs over 1 mo.The AA immediately improved after the first round.The patient was cured,and AA did not recur.Case 3:A 20-year-old woman,who was diagnosed with alopecia universalis at the age of 12,was given 14 rounds of MM-UC-MSCs over 12 mo.Her hair began to grow about 3 mo after the first round.The patient was cured,and alopecia universalis did not recur.CONCLUSION MM-UC-MSC transplantation potentially treats patients who suffer from AA and related diseases. 展开更多
关键词 Alopecia areata Umbilical cord-derived mesenchymal stem cells ALLOGENIC Cell therapy Minimal manipulation Case report
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Psoriasis treatment using minimally manipulated umbilical cordderived mesenchymal stem cells:A case report 被引量:4
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作者 Hyunjun Ahn Sang Yeon Lee +2 位作者 Won-Ju Jung Jia Pi Kye-Ho Lee 《World Journal of Clinical Cases》 SCIE 2021年第23期6798-6803,共6页
BACKGROUND Psoriasis is a chronic autoimmune disease that usually manifests as a red scaly epidermis,induration,and hyperproliferation of basal keratinocytes.About 2%of the world’s population suffers from psoriasis b... BACKGROUND Psoriasis is a chronic autoimmune disease that usually manifests as a red scaly epidermis,induration,and hyperproliferation of basal keratinocytes.About 2%of the world’s population suffers from psoriasis but there are no clear therapeutics yet.Recently,mesenchymal stem cells(MSCs)have been regarded as a therapeutic alternative for autoimmune diseases,as they possess immunosuppressive effects without risks.Human umbilical cord-derived MSCs effectively regulate immune cells and are characterized by low immunogenicity,which has many advantages in treating immune diseases.CASE SUMMARY The patient was a 47-year-old male,diagnosed with psoriasis in 1995.He had received various treatments for 25 years,but the psoriatic condition was not significantly improved.He was given three rounds of minimally manipulated umbilical cord-derived MSCs over 2 wk.The erythema gradually disappeared.Three months after the 1st round,all erythema completely disappeared,and the psoriasis did not recur.CONCLUSION Minimally manipulated umbilical cord-derived MSC transplantation can potentially treat patients who suffer from psoriasis. 展开更多
关键词 PSORIASIS Umbilical cord-derived mesenchymal stem cells ALLOGENIC Cell therapy Minimal manipulation Case report
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Treatment of acute ischemic stroke by minimally manipulated umbilical cord-derived mesenchymal stem cells transplantation:A case report 被引量:1
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作者 Hyunjun Ahn Sang Yeon Lee +1 位作者 Won Ju Jung Kye-Ho Lee 《World Journal of Stem Cells》 SCIE 2021年第8期1151-1159,共9页
BACKGROUND Stroke is one of the major causes of disability and death worldwide.Some treatments for stroke exist,but existing treatment methods have limitations such as difficulty in the regeneration of damaged neurona... BACKGROUND Stroke is one of the major causes of disability and death worldwide.Some treatments for stroke exist,but existing treatment methods have limitations such as difficulty in the regeneration of damaged neuronal cells of the brain.Recently,mesenchymal stem cells(MSCs)have been studied as a therapeutic alternative for stroke,and various preclinical and case studies have been reported.CASE SUMMARY A 55-year-old man suffered an acute stroke,causing paralysis in the left upper and lower limbs.He intravenously transplanted the minimally manipulated human umbilical cord-derived MSCs(MM-UC-MSCs)twice with an 8-d interval.At 65 wk after transplantation,the patient returned to his previous occupation as a veterinarian with no adverse reactions.CONCLUSION MM-UC-MSCs transplantation potentially treats patients who suffer from acute ischemic stroke. 展开更多
关键词 Acute ischemic stroke Behavioral disorder Umbilical cord-derived mesenchymal stem cells ALLOGENIC Cell therapy Minimal manipulation Case report
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Laser-manipulated the of a harmonically multiphoton transitions trapped particle
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作者 陈琼 海阔 海文华 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第12期3662-3667,共6页
A single particle magneto-confined in a one-dimensional (1D) quantum wire experiences a harmonic potential, and imposing a sharply focused laser beam on an appropriate site shapes a δ potential. The theoretical inv... A single particle magneto-confined in a one-dimensional (1D) quantum wire experiences a harmonic potential, and imposing a sharply focused laser beam on an appropriate site shapes a δ potential. The theoretical investigation has demonstrated that for a sufficiently strong δ pulse the quantum motional stationary state of the particle is one of the eigenstates of the free harmonic oscillator, and it is determined by the site of the laser beam uniquely, namely a quantum state is admissible if and only if the laser site is one of its nodes. The numerical computation shows that all the nodes of the lower energy states with quantum numbers n ≤ 20, except the coordinate origin, are mutually different. So we can manipulate the multiphoton transitions between the quantum states by adjusting the position of the laser δ pulse and realize the transition from an unknown higher excitation state to a required lower energy state. 展开更多
关键词 quantum wire magnetically trap laser manipulation multiphoton transition
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Using magnetic nanoparticles to manipulate biological objects
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作者 刘毅 高宇 徐臣杰 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期29-39,共11页
The use of magnetic nanoparticles (MNPs) for the manipulation of biological objects, including proteins, genes, cellular organelles, bacteria, cells, and organs, are reviewed. MNPs are popular candidates for control... The use of magnetic nanoparticles (MNPs) for the manipulation of biological objects, including proteins, genes, cellular organelles, bacteria, cells, and organs, are reviewed. MNPs are popular candidates for controlling and probing biological objects with a magnetic force. In the past decade, progress in the synthesis and surface engineering of MNPs has further enhanced this popularity. 展开更多
关键词 magnetic nanoparticles MANIPULATION biological objects
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A single micro-LED manipulation system based on micro-gripper 被引量:2
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作者 Jie Bai Pingjuan Niu +2 位作者 Erdan Gu Jianming Li Clarence Augustine TH Tee 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第2期41-48,共8页
Micro-LEDs(μLEDs)have advantages in terms of brightness,power consumption,and response speed.In addition,they can also be used as micro-sensors implanted in the body via flexible electronic skin.One of the key techni... Micro-LEDs(μLEDs)have advantages in terms of brightness,power consumption,and response speed.In addition,they can also be used as micro-sensors implanted in the body via flexible electronic skin.One of the key techniques involved in the fabrication ofμLED-based devices is transfer printing.Although numerous methods have been proposed for transfer printing,improving the yield ofμLED arrays is still a formidable task.In this paper,we propose a novel method for improving the yield ofμLED arrays transferred by the stamping method,using an innovative design of piezoelectrically driven asymmetric micro-gripper.Traditional grippers are too large to manipulateμLEDs,and therefore two micro-sized cantilevers are added at the gripper tips.AμLED manipulation system is constructed based on the micro-gripper together with a three-dimensional positioning system.Experimental results using this system show that it can be used successfully to manipulateμLED arrays. 展开更多
关键词 MICRO-GRIPPER Micro-LED Transfer printing MANIPULATION
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Recent progress in bio-inspired macrostructure array materials with special wettability—from surface engineering to functional applications 被引量:2
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作者 Zhongxu Lian Jianhui Zhou +4 位作者 Wanfei Ren Faze Chen Jinkai Xu Yanling Tian Huadong Yu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期208-256,共49页
Bio-inspired macrostructure array(MAA,size:submillimeter to millimeter scale)materials with special wettability(MAAMs-SW)have attracted significant research attention due to their outstanding performance in many appli... Bio-inspired macrostructure array(MAA,size:submillimeter to millimeter scale)materials with special wettability(MAAMs-SW)have attracted significant research attention due to their outstanding performance in many applications,including oil repellency,liquid/droplet manipulation,anti-icing,heat transfer,water collection,and oil–water separation.In this review,we focus on recent developments in the theory,design,fabrication,and application of bio-inspired MAAMs-SW.We first review the history of the basic theory of special wettability and discuss representative structures and corresponding functions of some biological surfaces,thus setting the stage for the design and fabrication of bio-inspired MAAMs-SW.We then summarize the fabrication methods of special wetting MAAs in terms of three categories:additive manufacturing,subtractive manufacturing,and formative manufacturing,as well as their diverse functional applications,providing insights into the development of these MAAMs-SW.Finally,the challenges and directions of future research on bio-inspired MAAMs-SW are briefy addressed.Worldwide efforts,progress,and breakthroughs from surface engineering to functional applications elaborated herein will promote the practical application of bio-inspired MAAMs-SW. 展开更多
关键词 macrostructure arrays SUPERHYDROPHOBIC 3D printing laser droplet manipulation
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Pre‑hatch thermal manipulation of embryos and post‑hatch baicalein supplementation mitigated heat stress in broiler chickens 被引量:1
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作者 Sadid Al Amaz Ajay Chaudhary +2 位作者 Prem Lal Mahato Rajesh Jha Birendra Mishra 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1071-1085,共15页
Background High environmental temperatures induce heat stress in broiler chickens,affecting their health and pro-duction performance.Several dietary,managerial,and genetics strategies have been tested with some succes... Background High environmental temperatures induce heat stress in broiler chickens,affecting their health and pro-duction performance.Several dietary,managerial,and genetics strategies have been tested with some success in mitigating heat stress(HS)in broilers.Developing novel HS mitigation strategies for sustaining broiler production is critically needed.This study investigated the effects of pre-hatch thermal manipulation(TM)and post-hatch baica-lein supplementation on growth performance and health parameters in heat-stressed broilers.Results Six hundred fertile Cobb 500 eggs were incubated for 21 d.After candling on embryonic day(ED)10,238 eggs were thermally manipulated at 38.5℃ with 55%relative humidity(RH)from ED 12 to 18,then transferred to the hatcher(ED 19 to 21,standard temperature)and 236 eggs were incubated at a controlled temperature(37.5℃)till hatch.After hatch,180-day-old chicks from both groups were raised in 36 pens(n=10 birds/pen,6 replicates per treatment).The treatments were:1)Control,2)TM,3)control heat stress(CHS),4)thermal manipulation heat stress(TMHS),5)control heat stress supplement(CHSS),and 6)thermal manipulation heat stress supplement(TMHSS).All birds were raised under the standard environment for 21 d,followed by chronic heat stress from d 22 to 35(32–33℃ for 8 h)in the CHS,TMHS,CHSS,and TMHSS groups.A thermoneutral(22–24℃)environment was maintained in the Control and TM groups.RH was constant(50%±5%)throughout the trial.All the data were analyzed using one-way ANOVA in R and GraphPad software at P<0.05 and are presented as mean±SEM.Heat stress significantly decreased(P<0.05)the final body weight and ADG in CHS and TMHS groups compared to the other groups.Embryonic TM significantly increased(P<0.05)the expression of heat shock protein-related genes(HSP70,HSP90,and HSPH1)and antioxidant-related genes(GPX1 and TXN).TMHS birds showed a significant increment(P<0.05)in total cecal volatile fatty acid(VFA)concentration compared to the CHS birds.The cecal microbial analysis showed significant enrichment(P<0.05)in alpha and beta diversity and Coprococcus in the TMHSS group.Conclusions Pre-hatch TM and post-hatch baicalein supplementation in heat-stressed birds mitigate the detrimental effects of heat stress on chickens’growth performance,upregulate favorable gene expression,increase VFA produc-tion,and promote gut health by increasing beneficial microbial communities. 展开更多
关键词 BAICALEIN Growth performance Gut microbiota Heat stress Thermal manipulation
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深海环境海洋生态系统监测与修复新技术 被引量:1
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作者 Jacopo Aguzzi Laurenz Thomsen +16 位作者 Sascha Flögel Nathan J.Robinson Giacomo Picardi Damianos Chatzievangelou Nixon Bahamon Sergio Stefanni Jordi Grinyó Emanuela Fanelli Cinzia Corinaldesi Joaquin Del Rio Fernandez Marcello Calisti Furu Mienis Elias Chatzidouros Corrado Costa Simona Violino Michael Tangherlini Roberto Danovaro 《Engineering》 SCIE EI CAS CSCD 2024年第3期195-211,共17页
The United Nations(UN)’s call for a decade of“ecosystem restoration”was prompted by the need to address the extensive impact of anthropogenic activities on natural ecosystems.Marine ecosystem restoration is increas... The United Nations(UN)’s call for a decade of“ecosystem restoration”was prompted by the need to address the extensive impact of anthropogenic activities on natural ecosystems.Marine ecosystem restoration is increasingly necessary due to increasing habitat degredation in deep waters(>200 m depth).At these depths,which are far beyond those accessible by divers,only established and emerging robotic platforms such as remotely operated vehicles(ROVs),autonomous underwater vehicles(AUVs),landers,and crawlers can operate through manipulators and multiparametric sensor arrays(e.g.,optoacoustic imaging,omics,and environmental probes).The use of advanced technologies for deep-sea ecosystem restoration can provide:①high-resolution three-dimensional(3D)imaging and acoustic mapping of substrates and key taxa,②physical manipulation of substrates and key taxa,③real-time supervision of remote operations and long-term ecological monitoring,and④the potential to work autonomously.Here,we describe how robotic platforms with in situ manipulation capabilities and payloads of innovative sensors could autonomously conduct active restoration and monitoring across large spatial scales.We expect that these devices will be particularly useful in deep-sea habitats,such as①reef-building cold-water corals,②soft-bottom bamboo corals,and③soft-bottom fishery resources that have already been damaged by offshore industries(i.e.,fishing and oil/gas). 展开更多
关键词 Ecosystem restoration Robotic manipulation Acoustic tracking Fishery resources Artificial reefs
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Triboelectric‘electrostatic tweezers'for manipulating droplets on lubricated slippery surfaces prepared by femtosecond laser processing 被引量:1
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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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A Coordinate-Free Approach to the Design of Generalized Griffis-Duffy Platforms
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作者 Chengwei Shen Xu Pei +1 位作者 Lubin Hang Jingjun Yu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期95-103,共9页
Architectural singularity belongs to the Type II singularity,in which a parallel manipulator(PM)gains one or more degrees of freedom and becomes uncontrollable.PMs remaining permanently in a singularity are beneficial... Architectural singularity belongs to the Type II singularity,in which a parallel manipulator(PM)gains one or more degrees of freedom and becomes uncontrollable.PMs remaining permanently in a singularity are beneficial for linearto-rotary motion conversion.Griffis-Duffy(GD)platform is a mobile structure admitting a Bricard motion.In this paper,we present a coordinate-free approach to the design of generalized GD platforms,which consists in determining the shape and attachment of both the moving platform and the fixed base.The generalized GD platform is treated as a combination of six coaxial single-loop mechanisms under the same constraints.Owing to the inversion,hidden in the geometric structure of these single-loop mechanisms,the mapping from a line to a circle establishes the geometric transformation between the fixed base and the moving platform based on the center of inversion,and describes the shape and attachment of the generalized GD platform.Moreover,the center of inversion not only identifies the location of rotation axis,but also affects the shape of the platform mechanism.A graphical construction of generalized GD platforms using inversion,proposed in the paper,provides geometrically feasible solutions of the manipulator design for the requirement of the location of rotation axis. 展开更多
关键词 Generalized Griffis-Duffy platforms SELF-MOTION INVERSION Coordinate-free determination Manipulator design
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Revolutionizing plasmonic platform via magnetic field-assisted confined ultrafast laser deposition of high-density,uniform,and ultrafine nanoparticle arrays
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作者 Jin Xu Lingfeng Wang +5 位作者 Peilin Yang Haoqing Jiang Huai Zheng Licong An Xingtao Liu Gary J Cheng 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期428-438,共11页
The remarkable capabilities of 2D plasmonic surfaces in controlling optical waves havegarnered significant attention.However,the challenge of large-scale manufacturing of uniform,well-aligned,and tunable plasmonic sur... The remarkable capabilities of 2D plasmonic surfaces in controlling optical waves havegarnered significant attention.However,the challenge of large-scale manufacturing of uniform,well-aligned,and tunable plasmonic surfaces has hindered their industrialization.To address this,we present a groundbreaking tunable plasmonic platform design achieved throughmagnetic field(MF)assisted ultrafast laser direct deposition in air.Through precise control of metal nanoparticles(NPs),with cobalt(Co)serving as the model material,employing an MF,and fine-tuning ultrafast laser parameters,we have effectively converted coarse and non-uniform NPs into densely packed,uniform,and ultrafine NPs(~3 nm).This revolutionary advancement results in the creation of customizable plasmonic‘hot spots,’which play a pivotal role insurface-enhanced Raman spectroscopy(SERS)sensors.The profound impact of this designable plasmonic platform lies in its close association with plasmonic resonance and energyenhancement.When the plasmonic nanostructures resonate with incident light,they generate intense local electromagnetic fields,thus vastly increasing the Raman scattering signal.This enhancement leads to an outstanding 2–18 fold boost in SERS performance and unparalleled sensing sensitivity down to 10^(-10)M.Notably,the plasmonic platform also demonstratesrobustness,retaining its sensing capability even after undergoing 50 cycles of rinsing andre-loading of chemicals.Moreover,this work adheres to green manufacturing standards,making it an efficient and environmentally friendly method for customizing plasmonic‘hot spots’inSERS devices.Our study not only achieves the formation of high-density,uniform,and ultrafine NP arrays on a tunable plasmonic platform but also showcases the profound relation betweenplasmonic resonance and energy enhancement.The outstanding results observed in SERS sensors further emphasize the immense potential of this technology for energy-relatedapplications,including photocatalysis,photovoltaics,and clean water,propelling us closer to a sustainable and cleaner future. 展开更多
关键词 magnetic field manipulation laser deposition metasurface SERS
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Particle distributions in Lamb wave based acoustofluidics
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作者 Chuanchao Zhang Xian Chen +3 位作者 Wei Wei Xuejiao Chen Quanning Li Xuexin Duan 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第2期60-68,共9页
Acoustic streaming enabled by a Lamb wave resonator(LWR)is efficient for particle trapping and enrichment in microfluidic channels.However,because Lamb waves combine the features of bulk acoustic waves and surface aco... Acoustic streaming enabled by a Lamb wave resonator(LWR)is efficient for particle trapping and enrichment in microfluidic channels.However,because Lamb waves combine the features of bulk acoustic waves and surface acoustic waves,the resulting acoustic streaming in the LWR occurs in multiple planes,and the particle flow behavior in this acoustofluidic system is largely unknown.Reported here are numerical simulations and laboratory experiments conducted to investigate the boundary conditions for particle motion inside a microvortex induced by an LWR.Upon dynamic capture,the particles’trajectories become orbital paths within an acoustic vortex.The suspended particles encounter two distinct acoustic phenomena,i.e.,the drag force resulting from acoustic streaming and the acoustic radiation force,which exert forces in various directions on the particles.When the acoustic radiation force and the fluid drag force are dominant for large and small particles in a mixed solution,respectively,the large particles reside within the vortex while the small particles remain at its periphery.Conversely,when the acoustic radiation force is dominant for both types of particles,the distribution pattern is reversed. 展开更多
关键词 Acoustofluidics Lamb wave resonator Particle manipulation Microvortex
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A 1-bit electronically reconfigurable beam steerable metasurface reflectarray with multiple polarization manipulations
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作者 史琰 徐茜雅 +2 位作者 王少泽 魏文岳 武全伟 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期384-394,共11页
A 1-bit electronically controlled metasurface reflectarray is presented to achieve beam steering with multiple polarization manipulations. A metsurface unit cell loaded by two PIN diodes is designed. By switching the ... A 1-bit electronically controlled metasurface reflectarray is presented to achieve beam steering with multiple polarization manipulations. A metsurface unit cell loaded by two PIN diodes is designed. By switching the two PIN diodes between ON and OFF states, the isotropic and anisotropic reflections can be flexibly achieved. For either the isotropic reflection or the anisotropic reflection, the two operation states achieve the reflection coefficients with approximately equal magnitude and 180°out of phase, thus giving rise to the isotropic/anisotropic 1-bit metasurface unit cells. With the 1-bit unit cells, a 12-by-12 metasurface reflectarray is optimally designed and fabricated. Under either y-or x-polarized incident wave illumination, the reflectarray can achieve the co-polarized and cross-polarized beam scanning, respectively, with the peak gains of 20.08 d Bi and 17.26 d Bi within the scan range of about ±50°. With the right-handed circular polarization(RHCP) excitation, the left-handed circular polarization(LHCP) radiation with the peak gain of 16.98 d Bic can be achieved within the scan range of ±50°. Good agreement between the experimental results and the simulation results are observed for 2D beam steering and polarization manipulation capabilities. 展开更多
关键词 electronically controlled metasurface reflectarray beam steering polarization manipulation
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Survey on Video Security:Examining Threats,Challenges,and Future Trends
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作者 Ali Asghar Amna Shifa Mamoona Naveed Asghar 《Computers, Materials & Continua》 SCIE EI 2024年第9期3591-3635,共45页
Videos represent the most prevailing form of digital media for communication,information dissemination,and monitoring.However,theirwidespread use has increased the risks of unauthorised access andmanipulation,posing s... Videos represent the most prevailing form of digital media for communication,information dissemination,and monitoring.However,theirwidespread use has increased the risks of unauthorised access andmanipulation,posing significant challenges.In response,various protection approaches have been developed to secure,authenticate,and ensure the integrity of digital videos.This study provides a comprehensive survey of the challenges associated with maintaining the confidentiality,integrity,and availability of video content,and examining how it can be manipulated.It then investigates current developments in the field of video security by exploring two critical research questions.First,it examine the techniques used by adversaries to compromise video data and evaluate their impact.Understanding these attack methodologies is crucial for developing effective defense mechanisms.Second,it explores the various security approaches that can be employed to protect video data,enhancing its transparency,integrity,and trustworthiness.It compares the effectiveness of these approaches across different use cases,including surveillance,video on demand(VoD),and medical videos related to disease diagnostics.Finally,it identifies potential research opportunities to enhance video data protection in response to the evolving threat landscape.Through this investigation,this study aims to contribute to the ongoing efforts in securing video data,providing insights that are vital for researchers,practitioners,and policymakers dedicated to enhancing the safety and reliability of video content in our digital world. 展开更多
关键词 ATTACKS threats security services video manipulation video security
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Many faces of neuronal activity manipulation in Drosophila
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作者 Amber Krebs Steffen Kautzmann Christian Klämbt 《Neural Regeneration Research》 SCIE CAS 2025年第9期2574-2576,共3页
Animals exhibit complex responses to external and internal stimuli.The information is computed by interconnected neurons that express numerous ion channels,which modulate the neuronal membrane potential.How can neuron... Animals exhibit complex responses to external and internal stimuli.The information is computed by interconnected neurons that express numerous ion channels,which modulate the neuronal membrane potential.How can neuronal activity orchestrate complex motor patterns or allow learning from previous experience?To answer such questions,we need the ability not only to record,but also to modulate neuronal activity in both space(e.g.,neuronal subsets)and time. 展开更多
关键词 MANIPULATION potential. NEURONAL
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