期刊文献+
共找到870篇文章
< 1 2 44 >
每页显示 20 50 100
Minimally manipulated autologous adherent bone marrow cells (ABMCs):a promising cell therapy of spinal cord injury 被引量:3
1
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
下载PDF
Alopecia treatment using minimally manipulated human umbilical cord-derived mesenchymal stem cells:Three case reports and review of literature 被引量:4
2
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
下载PDF
Psoriasis treatment using minimally manipulated umbilical cordderived mesenchymal stem cells:A case report 被引量:3
3
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
下载PDF
Treatment of acute ischemic stroke by minimally manipulated umbilical cord-derived mesenchymal stem cells transplantation:A case report 被引量:1
4
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
下载PDF
Laser-manipulated the of a harmonically multiphoton transitions trapped particle
5
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
下载PDF
Pre‑hatch thermal manipulation of embryos and post‑hatch baicalein supplementation mitigated heat stress in broiler chickens
6
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
下载PDF
Recent progress in bio-inspired macrostructure array materials with special wettability—from surface engineering to functional applications
7
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
下载PDF
深海环境海洋生态系统监测与修复新技术
8
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
下载PDF
A 1-bit electronically reconfigurable beam steerable metasurface reflectarray with multiple polarization manipulations
9
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
下载PDF
A Novel Disturbance Observer Based Fixed-Time Sliding Mode Control for Robotic Manipulators With Global Fast Convergence
10
作者 Dan Zhang Jiabin Hu +2 位作者 Jun Cheng Zheng-Guang Wu Huaicheng Yan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期661-672,共12页
This paper proposes a new global fixed-time sliding mode control strategy for the trajectory tracking control of uncertain robotic manipulators.First,a fixed-time disturbance observer(FTDO) is designed to deal with th... This paper proposes a new global fixed-time sliding mode control strategy for the trajectory tracking control of uncertain robotic manipulators.First,a fixed-time disturbance observer(FTDO) is designed to deal with the adverse effects of model uncertainties and external disturbances in the manipulator systems.Then an adaptive scheme is used and the adaptive FTDO(AFTDO) is developed,so that the priori knowledge of the lumped disturbance is not required.Further,a new non-singular fast terminal sliding mode(NFTSM) surface is designed by using an arctan function,which helps to overcome the singularity problem and enhance the robustness of the system.Based on the estimation of the lumped disturbance by the AFTDO,a fixed-time non-singular fast terminal sliding mode controller(FTNFTSMC)is developed to guarantee the trajectory tracking errors converge to zero within a fixed time.The settling time is independent of the initial state of the system.In addition,the stability of the AFTDO and FTNFTSMC is strictly proved by using Lyapunov method.Finally,the fixed-time NFESM(FTNFTSM) algorithm is validated on a 2-link manipulator and comparisons with other existing sliding mode controllers(SMCs) are performed.The comparative results confirm that the FTNFTSMC has superior control performance. 展开更多
关键词 Disturbance observer(DO) fixed-time non-singular sliding mode control robotic manipulator trajectory tracking
下载PDF
Spatial quantum coherent modulation with perfect hybrid vector vortex beam based on atomic medium
11
作者 马燕 杨欣 +6 位作者 常虹 杨鑫琪 曹明涛 张晓斐 高宏 董瑞芳 张首刚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期360-364,共5页
The perfect hybrid vector vortex beam(PHVVB)with helical phase wavefront structure has aroused significant concern in recent years,as its beam waist does not expand with the topological charge(TC).In this work,we inve... The perfect hybrid vector vortex beam(PHVVB)with helical phase wavefront structure has aroused significant concern in recent years,as its beam waist does not expand with the topological charge(TC).In this work,we investigate the spatial quantum coherent modulation effect with PHVVB based on the atomic medium,and we observe the absorption characteristic of the PHVVB with different TCs under variant magnetic fields.We find that the transmission spectrum linewidth of PHVVB can be effectively maintained regardless of the TC.Still,the width of transmission peaks increases slightly as the beam size expands in hot atomic vapor.This distinctive quantum coherence phenomenon,demonstrated by the interaction of an atomic medium with a hybrid vector-structured beam,might be anticipated to open up new opportunities for quantum coherence modulation and accurate magnetic field measurement. 展开更多
关键词 perfect hybrid vector vortex beam topological charge quantum coherence optical manipulation
下载PDF
Scheme of negative acoustic radiation force based on a multiple-layered spherical structure
12
作者 宫门阳 徐鑫 +3 位作者 乔玉配 刘杰惠 何爱军 刘晓宙 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期477-487,共11页
Acoustic radiation force(ARF), as an important particle manipulation method, has been extensively studied in recent years. With the introduction of the concept of “acoustic tweezers”, negative acoustic radiation has... Acoustic radiation force(ARF), as an important particle manipulation method, has been extensively studied in recent years. With the introduction of the concept of “acoustic tweezers”, negative acoustic radiation has become a research hotspot. In this paper, a scheme of realizing negative ARF based on the multiple-layered spherical structure design is proposed. The specific structure and design idea are presented. Detailed theoretical calculation analysis is carried out.Numerical simulations have been performed to verify the correctness of this prediction. The conjecture that the suppression of backscattering can achieve negative ARF is verified concretely, which greatly expands the application prospect and design ideas of the ARF. This work has laid a theoretical foundation for realizing precise control of the structure. 展开更多
关键词 acoustic tweezers negative acoustic radiation force particle manipulation
下载PDF
New avenues for the treatment of immunotherapy-resistant pancreatic cancer
13
作者 Luis Guilherme de Oliveira Silva Fabian Fellipe Bueno Lemos +5 位作者 Marcel Silva Luz Samuel Luca Rocha Pinheiro Mariana dos Santos Calmon Gabriel Lima Correa Santos Gabriel Reis Rocha Fabrício Freire de Melo 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第4期1134-1153,共20页
Pancreatic cancer(PC)is characterized by its extremely aggressive nature and ranks 14th in the number of new cancer cases worldwide.However,due to its complexity,it ranks 7th in the list of the most lethal cancers wor... Pancreatic cancer(PC)is characterized by its extremely aggressive nature and ranks 14th in the number of new cancer cases worldwide.However,due to its complexity,it ranks 7th in the list of the most lethal cancers worldwide.The pathogenesis of PC involves several complex processes,including familial genetic factors associated with risk factors such as obesity,diabetes mellitus,chronic pancreatitis,and smoking.Mutations in genes such as KRAS,TP53,and SMAD4 are linked to the appearance of malignant cells that generate pancreatic lesions and,consequently,cancer.In this context,some therapies are used for PC,one of which is immunotherapy,which is extremely promising in various other types of cancer but has shown little response in the treatment of PC due to various resistance mechanisms that contribute to a drop in immunotherapy efficiency.It is therefore clear that the tumor microenvironment(TME)has a huge impact on the resistance process,since cellular and non-cellular elements create an immunosuppressive environment,characterized by a dense desmoplastic stroma with cancerassociated fibroblasts,pancreatic stellate cells,extracellular matrix,and immunosuppressive cells.Linked to this are genetic mutations in TP53 and immunosuppressive factors that act on T cells,resulting in a shortage of CD8+T cells and limited expression of activation markers such as interferon-gamma.In this way,finding new strategies that make it possible to manipulate resistance mechanisms is necessary.Thus,techniques such as the use of TME modulators that block receptors and stromal molecules that generate resistance,the use of genetic manipulation in specific regions,such as microRNAs,the modulation of extrinsic and intrinsic factors associated with T cells,and,above all,therapeutic models that combine these modulation techniques constitute the promising future of PC therapy.Thus,this study aims to elucidate the main mechanisms of resistance to immunotherapy in PC and new ways of manipulating this process,resulting in a more efficient therapy for cancer patients and,consequently,a reduction in the lethality of this aggressive cancer. 展开更多
关键词 Pancreatic cancer IMMUNOTHERAPY RESISTANCE Tumor microenvironment MANIPULATION Combined immunotherapy
下载PDF
Manipulator tracking technology based on FSRUKF
14
作者 SHI Guoqing ZHANG Boyan +5 位作者 ZHANG Jiandong YANG Qiming HUANG Xiaofeng QUE Jianyao PU Junwei GENG Xiutang 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期473-484,共12页
Aiming at the shortcoming that the traditional industrial manipulator using off-line programming cannot change along with the change of external environment,the key technologies such as machine vision and manipulator ... Aiming at the shortcoming that the traditional industrial manipulator using off-line programming cannot change along with the change of external environment,the key technologies such as machine vision and manipulator control are studied,and a complete manipulator vision tracking system is designed.Firstly,Denavit-Hartenberg(D-H)parameters method is used to construct the model of the manipulator and analyze the forward and inverse kinematics equations of the manipulator.At the same time,a binocular camera is used to obtain the threedimensional position of the target.Secondly,in order to make the manipulator track the target more accurately,the fuzzy adaptive square root unscented Kalman filter(FSRUKF)is proposed to estimate the target state.Finally,the manipulator tracking system is built by using the position-based visual servo.The simulation experiments show that FSRUKF converges faster and with less error than the square root unscented Kalman filter(SRUKF),which meets the application requirements of the manipulator tracking system,and basically meets the application requirements of the manipulator tracking system in the practical experiments. 展开更多
关键词 square root unscented Kalman filter(SRUKF) fuzzy inference MANIPULATOR visual servo
下载PDF
Neural Dynamics for Cooperative Motion Control of Omnidirectional Mobile Manipulators in the Presence of Noises: A Distributed Approach
15
作者 Yufeng Lian Xingtian Xiao +3 位作者 Jiliang Zhang Long Jin Junzhi Yu Zhongbo Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第7期1605-1620,共16页
This paper presents a distributed scheme with limited communications, aiming to achieve cooperative motion control for multiple omnidirectional mobile manipulators(MOMMs).The proposed scheme extends the existing singl... This paper presents a distributed scheme with limited communications, aiming to achieve cooperative motion control for multiple omnidirectional mobile manipulators(MOMMs).The proposed scheme extends the existing single-agent motion control to cater to scenarios involving the cooperative operation of MOMMs. Specifically, squeeze-free cooperative load transportation is achieved for the end-effectors of MOMMs by incorporating cooperative repetitive motion planning(CRMP), while guiding each individual to desired poses. Then, the distributed scheme is formulated as a time-varying quadratic programming(QP) and solved online utilizing a noise-tolerant zeroing neural network(NTZNN). Theoretical analysis shows that the NTZNN model converges globally to the optimal solution of QP in the presence of noise. Finally, the effectiveness of the control design is demonstrated by numerical simulations and physical platform experiments. 展开更多
关键词 Cooperative motion control noise-tolerant zeroing neural network(NTZNN) omnidirectional mobile manipulator(OMM) repetitive motion planning
下载PDF
Unexpected Twinning and Phase-Transition of the Indentation Standards, Their Transition Energies, and Scientific Dichotomy
16
作者 Gerd Kaupp 《Journal of Applied Mathematics and Physics》 2024年第6期2119-2159,共41页
The general use of aluminium as an indentation standard for the iteration of contact heights for the determination of ISO-14577 hardness and elastic modulus is challenged because of as yet not appreciated phase-change... The general use of aluminium as an indentation standard for the iteration of contact heights for the determination of ISO-14577 hardness and elastic modulus is challenged because of as yet not appreciated phase-changes in the physical force-depth standard curve that seemed to be secured by claims from 1992. The physical and mathematical analyses with closed formulas avoid the still world-wide standardized energy-law violation by not reserving 33.33% (h2 belief) (or 20% h3/2 physical law) of the loading force and thus energy for all not depth producing events but using 100% for the depth formation is a severe violation of the energy law. The not depth producing part of the indentation work cannot be done with zero energy! Both twinning and structural phase-transition onsets and normalized phase-transition energies are now calculated without iterations but with physically correct closed arithmetic equations. These are reported for Berkovich and cubecorner indentations, including their comparison on geometric grounds and an indentation standard without mechanical twinning is proposed. Characteristic data are reported. This is the first detection of the indentation twinning of aluminium at room temperature and the mechanical twinning of fused quartz is also new. Their disqualification as indentation standards is established. Also, the again found higher load phase-transitions disqualify aluminium and fused quartz as ISO-ASTM 14577 (International Standardization Organization and American Society for Testing and Materials) standards for the contact depth “hc” iterations. The incorrect and still world-wide used black-box values for H- and Er-values (the latter are still falsely called “Young’s moduli” even though they are not directional) and all mechanical properties that depend on them. They lack relation to bulk moduli from compression experiments. Experimentally obtained and so published force vs depth parabolas always follow the linear FN = kh3/2 + Fa equation, where Fa is the axis-cut before and after the phase-transition branches (never “h2” as falsely enforced and used for H, Er and giving incorrectly calculated parameters). The regression slopes k are the precise physical hardness values, which for the first time allow for precise calculation of the mechanical qualities by indentation in relation to the geometry of the indenter tip. Exactly 20% of the applied force and thus energy is not available for the indentation depth. Only these scientific k-values must be used for AI-advises at the expense of falsely iterated indentation hardness H-values. Any incorrect H-ISO-ASTM and also the iterated Er-ISO-ASTM modulus values of technical materials in artificial intelligence will be a disaster for the daily safety. The AI must be told that these are unscientific and must therefore be replaced by physical data. Iterated data (3 and 8 free parameters!) cannot be transformed into physical data. One has to start with real experimental loading curves and an absolute ZerodurR standard that must be calibrated with standard force and standard length to create absolute indentation results. . 展开更多
关键词 Aluminium Fused Quartz Copper TWINNING Structural Phase-Transitions Undue Indentation Standards Data Manipulation ZerodurR Absolute Hardness
下载PDF
Spintronic terahertz emission with manipulated polarization (STEMP) 被引量:1
17
作者 Peiyan Li Shaojie Liu +2 位作者 Xinhou Chen Chunyan Geng Xiaojun Wu 《Frontiers of Optoelectronics》 EI CSCD 2022年第1期128-142,共15页
Highly efficient generation and arbitrary manipulation of spin-polarized terahertz(THz)radiation will enable chiral lightwave driven quantum nonequilibrium state regulation,induce new electronic structures,consequentl... Highly efficient generation and arbitrary manipulation of spin-polarized terahertz(THz)radiation will enable chiral lightwave driven quantum nonequilibrium state regulation,induce new electronic structures,consequently provide a powerful experi-mental tool for investigation of nonlinear THz optics and extreme THz science and applications.THz circular dichromic spectroscopy,ultrafast electron bunch manipulation,as well as THz imaging,sensing,and telecommunication,also need chiral THz waves.Here we review optical generation of circularly-polarized THz radiation but focus on recently emerged polarization tunable spintronic THz emission techniques,which possess many advantages of ultra-broadband,high efficiency,low cost,easy for integration and so on.We believe that chiral THz sources based on the combination of electron spin,ultra-fast optical techniques and material structure engineering will accelerate the development of THz science and applications. 展开更多
关键词 Terahertz(THz)emission Femtosecond laser SPINTRONICS Polarization manipulation
原文传递
Current advances of transition metal dichalcogenides in electromagnetic wave absorption:A brief review 被引量:3
18
作者 Shijie Zhang Jiying Li +1 位作者 Xiaotian Jin Guanglei Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第3期428-445,共18页
Transition metal dichalcogenides(TMDs)show great advantages in electromagnetic wave(EMW)absorption due to their unique structure and electrical properties.Tremendous research works on TMD-based EMW absorbers have been... Transition metal dichalcogenides(TMDs)show great advantages in electromagnetic wave(EMW)absorption due to their unique structure and electrical properties.Tremendous research works on TMD-based EMW absorbers have been conducted in the last three years,and the comprehensive and systematical summary is still a rarity.Therefore,it is of great significance to elaborate on the interaction among the morphologies,structures,phases,components,and EMW absorption performances of TMD-based absorbers.This review is devoted to analyzing TMD-based absorbers from the following perspectives:the EMW absorption regulation strategies of TMDs and the latest progress of TMD-based hybrids as EMW absorbers.The absorption mechanisms and component-performance dependency of these achievements are also summarized.Finally,a straightforward insight into industrial revolution upgrading in this promising field is proposed. 展开更多
关键词 transition metal dichalcogenides phase manipulation HYBRIDS hierarchical structure absorption mechanism
下载PDF
Phosphate deficiency induced by infection promotes synthesis of anthracnose-resistant anthocyanin-3-O-galactoside phytoalexins in the Camellia sinensis plant 被引量:2
19
作者 Tongtong Li Shenrong Wang +6 位作者 Dandan Shi Wen Fang Ting Jiang Lixin Zhang Yajun Liu Liping Gao Tao Xia 《Horticulture Research》 SCIE CSCD 2023年第12期137-151,共15页
Tea(Camellia sinensis)is a well-known beverage crop rich in polyphenols with health benefits for humans.Understanding how tea polyphenols participate in plant resistance is beneficial to breeding resistant varieties a... Tea(Camellia sinensis)is a well-known beverage crop rich in polyphenols with health benefits for humans.Understanding how tea polyphenols participate in plant resistance is beneficial to breeding resistant varieties and uncovering the resistance mechanisms.Here,we report that a Colletotrichum infection-induced‘pink ring’symptom appeared outside the lesion,which is highly likely to occur in resistant cultivars.By identifying morphological feature-specific metabolites in the pink ring and their association with disease resistance,and analysis of the association between metabolite and gene expression,the study revealed that the accumulation of anthocyanin-3-O-galactosides,red phytotoxin compounds resistant to anthracnose,plays a pivotal role in the hypersensitive response surrounding infection sites in tea plants.The results of genetic manipulation showed that the expression of CsF3Ha,CsANSa,CsUGT78A15,CsUGT75L43,and CsMYB113,which are involved in anthocyanin biosynthesis,is positively correlated with anthracnose-resistance and the formation of the pink ring.Further phosphorus quantification and fertilization experiments confirmed that phosphate deficiency caused by anthracnose is involved in the occurrence of the pink ring.Genetic manipulation studies indicated that altering the expression levels of Pi transporter proteins(CsPHT2-1,CsPHT4;4)and phosphate deprivation response transcription factors(CsWRKY75-1,CsWRKY75-2,CsMYB62-1)enhances resistance to anthracnose and the formation of the pink ring symptom in tea plants.This article provides the first evidence that anthocyanin-3-O-galactosides are the anthracnose-resistant phytoalexins among various polyphenols in tea plants,and this presents an approach for identifying resistance genes in tea plants,where genetic transformation is challenging. 展开更多
关键词 INFECTION manipulation RESISTANT
下载PDF
Adaptive Leader-Follower Consensus Control of Multiple Flexible Manipulators With Actuator Failures and Parameter Uncertainties 被引量:2
20
作者 Yu Liu Lin Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第4期1020-1031,共12页
In this paper,the leader-follower consensus problem for a multiple flexible manipulator network with actuator failures,parameter uncertainties,and unknown time-varying boundary disturbances is addressed.The purpose of... In this paper,the leader-follower consensus problem for a multiple flexible manipulator network with actuator failures,parameter uncertainties,and unknown time-varying boundary disturbances is addressed.The purpose of this study is to develop distributed controllers utilizing local interactive protocols that not only suppress the vibration of each flexible manipulator but also achieve consensus on joint angle position between actual followers and the virtual leader.Following the accomplishment of the reconstruction of the fault terms and parameter uncertainties,the adaptive neural network method and parameter estimation technique are employed to compensate for unknown items and bounded disturbances.Furthermore,the Lyapunov stability theory is used to demonstrate that followers’angle consensus errors and vibration deflections in closed-loop systems are uniformly ultimately bounded.Finally,the numerical simulation results confirm the efficacy of the proposed controllers. 展开更多
关键词 Actuator failures leader-follower consensus multiple flexible manipulators neural network parameter uncertainties
下载PDF
上一页 1 2 44 下一页 到第
使用帮助 返回顶部