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3D printing of poly(ethyleneimine)-functionalized Mg-Al mixed metal oxide monoliths for direct air capture of CO_(2)
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作者 Qingyang Shao Zhuozhen Gan +4 位作者 Bingyao Ge Xuyi Liu Chunping Chen Dermot O’Hare Xuancan Zhu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期491-500,共10页
Direct air capture(DAC)of CO_(2)plays an indispensable role in achieving carbon-neutral goals as one of the key negative emission technologies.Since large air flows are required to capture the ultradilute CO_(2)from t... Direct air capture(DAC)of CO_(2)plays an indispensable role in achieving carbon-neutral goals as one of the key negative emission technologies.Since large air flows are required to capture the ultradilute CO_(2)from the air,lab-synthesized adsorbents in powder form may cause unacceptable gas pressure drops and poor heat and mass transfer efficiencies.A structured adsorbent is essential for the implementation of gas-solid contactors for cost-and energy-efficient DAC systems.In this study,efficient adsorbent poly(ethyleneimine)(PEI)-functionalized Mg-Al-CO_(3)layered double hydroxide(LDH)-derived mixed metal oxides(MMOs)are three-dimensional(3D)printed into monoliths for the first time with more than 90%adsorbent loadings.The printing process has been optimized by initially printing the LDH powder into monoliths followed by calcination into MMO monoliths.This structure exhibits a 32.7%higher specific surface area and a 46.1%higher pore volume,as compared to the direct printing of the MMO powder into a monolith.After impregnation of PEI,the monolith demonstrates a large adsorption capacity(1.82 mmol/g)and fast kinetics(0.7 mmol/g/h)using a CO_(2)feed gas at 400 ppm at 25℃,one of the highest values among the shaped DAC adsorbents.Smearing of the amino-polymers during the post-printing process affects the diffusion of CO_(2),resulting in slower adsorption kinetics of pre-impregnation monoliths compared to post-impregnation monoliths.The optimal PEI/MeOH ratio for the post-impregnation solution prevents pores clogging that would affect both adsorption capacity and kinetics. 展开更多
关键词 3d printing Mixed metal oxides Amine functionalization Structured adsorbent direct air capture
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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3d Model Schrödinger Equation RMS KLEIN GORdON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field density Phase Flow Attraction REPULSION Shell Theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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Cortico-striatal gamma oscillations are modulated by dopamine D3 receptors in dyskinetic rats
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作者 Pengfei Wang Yuewei Bi +6 位作者 Min Li Jiazhi Chen Zhuyong Wang Huantao Wen Ming Zhou Minjie Luo Wangming Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第4期1164-1177,共14页
Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Cu... Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Currently,studies have reported increased oscillation power in cases of levodopa-induced dyskinesia.However,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced dyskinesia.Furthermore,the role of the dopamine D3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is unclear.We found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s disease.Furthermore,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma flow.Administration of PD128907(a selective dopamine D3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum flow.However,administration of PG01037(a selective dopamine D3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum direction.These findings suggest that the dopamine D3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia. 展开更多
关键词 aperiodic components dopamine d3 receptor dorsolateral striatum functional connectivity gamma oscillations levodopa-induced-dyskinesia local field potentials NEUROMOdULATION Parkinson’s disease primary motor cortex
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Movement Function Assessment Based on Human Pose Estimation from Multi-View
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作者 Lingling Chen Tong Liu +1 位作者 Zhuo Gong Ding Wang 《Computer Systems Science & Engineering》 2024年第2期321-339,共19页
Human pose estimation is a basic and critical task in the field of computer vision that involves determining the position(or spatial coordinates)of the joints of the human body in a given image or video.It is widely u... Human pose estimation is a basic and critical task in the field of computer vision that involves determining the position(or spatial coordinates)of the joints of the human body in a given image or video.It is widely used in motion analysis,medical evaluation,and behavior monitoring.In this paper,the authors propose a method for multi-view human pose estimation.Two image sensors were placed orthogonally with respect to each other to capture the pose of the subject as they moved,and this yielded accurate and comprehensive results of three-dimensional(3D)motion reconstruction that helped capture their multi-directional poses.Following this,we propose a method based on 3D pose estimation to assess the similarity of the features of motion of patients with motor dysfunction by comparing differences between their range of motion and that of normal subjects.We converted these differences into Fugl–Meyer assessment(FMA)scores in order to quantify them.Finally,we implemented the proposed method in the Unity framework,and built a Virtual Reality platform that provides users with human–computer interaction to make the task more enjoyable for them and ensure their active participation in the assessment process.The goal is to provide a suitable means of assessing movement disorders without requiring the immediate supervision of a physician. 展开更多
关键词 Human pose estimation 3d pose reconstruction assessment of movement function plane of features of human motion
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Electrostatic Attraction and Repulsion Explained and Modelled Mathematically Using Classical Physics—A Detailed Mechanism Based on Particle Wave Functions
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1050-1062,共13页
The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has... The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has been no mechanistic explanation that reveals what causes the charged particles to accelerate, either towards or away from each other. This paper gives a detailed explanation of the phenomena of electrical attraction and repulsion based on my previous work that determined the exact wave-function solutions for both the Electron and the Positron. It is revealed that the effects are caused by wave interactions between the wave functions that result in Electromagnetic reflections of parts of the particle’s wave functions, causing a change in their momenta. 展开更多
关键词 ELECTROSTATIC Electron POSITRON COULOMB Force ATTRACTION REPULSION Wave function Electric Magnetic Radiation Pressure Shell THEOREM 3d Computer Model Quantum
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Low-temperature 3D-printed collagen/chitosan scaffolds loaded with exosomes derived from neural stem cells pretreated with insulin growth factor-1 enhance neural regeneration after traumatic brain injury 被引量:3
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作者 Xiao-Yin Liu Yin-He Feng +7 位作者 Qing-Bo Feng Jian-Yong Zhang Lin Zhong Peng Liu Shan Wang Yan-Ruo Huang Xu-Yi Chen Liang-Xue Zhou 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第9期1990-1998,共9页
There are various clinical treatments for traumatic brain injury,including surgery,drug therapy,and rehabilitation therapy;howeve r,the therapeutic effects are limited.Scaffolds combined with exosomes represent a prom... There are various clinical treatments for traumatic brain injury,including surgery,drug therapy,and rehabilitation therapy;howeve r,the therapeutic effects are limited.Scaffolds combined with exosomes represent a promising but challenging method for improving the repair of traumatic brain injury.In this study,we determined the ability of a novel 3D-printed collagen/chitosan scaffold loaded with exosomes derived from neural stem cells pretreated with insulin-like growth factor-1(3D-CC-INEXOS) to improve traumatic brain injury repair and functional recove ry after traumatic brain injury in rats.Composite scaffolds comprising collagen,chitosan,and exosomes derived from neural stem cells pretreated with insulin-like growth fa ctor-1(INEXOS) continuously released exosomes for 2weeks.Transplantation of 3D-CC-INExos scaffolds significantly improved motor and cognitive functions in a rat traumatic brain injury model,as assessed by the Morris water maze test and modified neurological seve rity scores.In addition,immunofluorescence staining and transmission electron microscopy showed that3D-CC-INExos implantation significantly improved the recove ry of damaged nerve tissue in the injured area.In conclusion,this study suggests that transplanted3D-CC-INExos scaffolds might provide a potential strategy for the treatment of traumatic brain injury and lay a solid foundation for clinical translation. 展开更多
关键词 3d printing ANGIOGENESIS chitosan COLLAGEN EXOSOMES functional recovery insulin-like growth factor-1 neural regeneration neural stem cells traumatic brain injury
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Ultrathin poly(cyclocarbonate-ether)-based composite electrolyte reinforced with high-strength functional skeleton 被引量:1
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作者 Xiaojiao Zheng Da Xu +1 位作者 Ning Fu Zhenglong Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期603-612,I0013,共11页
Composite polymer electrolytes(CPEs)are considered to be the most promising to break through the performance and safety limitations of traditional lithium-ion batteries because of their excellent electrochemical and m... Composite polymer electrolytes(CPEs)are considered to be the most promising to break through the performance and safety limitations of traditional lithium-ion batteries because of their excellent electrochemical and mechanical properties.Aiming at the performance limitations of the most common polyether matrix such as poly(ethylene oxide)(PEO),a novel poly(cyclocarbonate-ether)polymer matrix was prepared by in-situ thermal curing,the weaker interaction between its C=O bond and Li^(+)can promote the rapid transport of Li^(+).Adding ionic liquid and active filler LLZTO to the matrix can synergistically reduce the crystallinity of matrix and promote the dissociation of lithium salts.In addition,a 3D functional skeleton made of polyacrylonitrile(PAN)and lithium fluoride(LiF)can greatly improve the mechanical strength of polymer matrix after cold pressing,and Li F is also conducive to interface stability.The thickness of the optimal sample(VP6L/CPL)was only 25μm,and its ionic conductivity,lithium ion transference number,and electrochemical stability window were as high as 7.17×10^(-4)S cm^(-1)(25℃),0.54 and 5.4 V,respectively,while the mechanical strength reaches 6.1 MPa,which can fully inhibit the growth of lithium dendrites.The excellent electrochemical performance and mechanical strength enable the assembled Li|VP6L/CPL|Li battery to be continuously charged for over 200 h and cycled stably for more than 2300 h,and Li|VP6L/CPL|LFP battery can be stably cycled for more than 400 and 550 cycles at 1 C(40℃)and 0.5 C(25℃),respectively. 展开更多
关键词 Composite polymer electrolytes Polymer matrix 3d functional skeleton PLASTICIZATION Synergistic effect
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Advances in 3D printing scaffolds for peripheral nerve and spinal cord injury repair 被引量:1
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作者 Juqing Song Baiheng Lv +2 位作者 Wencong Chen Peng Ding Yong He 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第3期264-300,共37页
Because of the complex nerve anatomy and limited regeneration ability of natural tissue,the current treatment effect for long-distance peripheral nerve regeneration and spinal cord injury(SCI)repair is not satisfactor... Because of the complex nerve anatomy and limited regeneration ability of natural tissue,the current treatment effect for long-distance peripheral nerve regeneration and spinal cord injury(SCI)repair is not satisfactory.As an alternative method,tissue engineering is a promising method to regenerate peripheral nerve and spinal cord,and can provide structures and functions similar to natural tissues through scaffold materials and seed cells.Recently,the rapid development of 3D printing technology enables researchers to create novel 3D constructs with sophisticated structures and diverse functions to achieve high bionics of structures and functions.In this review,we first outlined the anatomy of peripheral nerve and spinal cord,as well as the current treatment strategies for the peripheral nerve injury and SCI in clinical.After that,the design considerations of peripheral nerve and spinal cord tissue engineering were discussed,and various 3D printing technologies applicable to neural tissue engineering were elaborated,including inkjet,extrusion-based,stereolithography,projection-based,and emerging printing technologies.Finally,we focused on the application of 3D printing technology in peripheral nerve regeneration and spinal cord repair,as well as the challenges and prospects in this research field. 展开更多
关键词 peripheral nerve regeneration spinal cord repair 3d printing construct bionic structure bionic function
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A methodology for damage evaluation of underground tunnels subjected to static loading using numerical modeling 被引量:1
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作者 Shahriyar Heidarzadeh Ali Saeidi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期1993-2005,共13页
We have proposed a methodology to assess the robustness of underground tunnels against potential failure.This involves developing vulnerability functions for various qualities of rock mass and static loading intensiti... We have proposed a methodology to assess the robustness of underground tunnels against potential failure.This involves developing vulnerability functions for various qualities of rock mass and static loading intensities.To account for these variations,we utilized a Monte Carlo Simulation(MCS)technique coupled with the finite difference code FLAC^(3D),to conduct two thousand seven hundred numerical simulations of a horseshoe tunnel located within a rock mass with different geological strength index system(GSIs)and subjected to different states of static loading.To quantify the severity of damage within the rock mass,we selected one stress-based(brittle shear ratio(BSR))and one strain-based failure criterion(plastic damage index(PDI)).Based on these criteria,we then developed fragility curves.Additionally,we used mathematical approximation techniques to produce vulnerability functions that relate the probabilities of various damage states to loading intensities for different quality classes of blocky rock mass.The results indicated that the fragility curves we obtained could accurately depict the evolution of the inner and outer shell damage around the tunnel.Therefore,we have provided engineers with a tool that can predict levels of damages associated with different failure mechanisms based on variations in rock mass quality and in situ stress state.Our method is a numerically developed,multi-variate approach that can aid engineers in making informed decisions about the robustness of underground tunnels. 展开更多
关键词 Fragility curves Underground tunnels Vulnerability functions Brittle damage FLAC3d Numerical modeling
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Bowel function and quality of life after minimally invasive colectomy with D3 lymphadenectomy for right-sided colon adenocarcinoma 被引量:2
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作者 Ki-Myung Lee Se-Jin Baek +2 位作者 Jung-Myun Kwak Jin Kim Seon-Hahn Kim 《World Journal of Gastroenterology》 SCIE CAS 2020年第33期4972-4982,共11页
BACKGROUND Changes in bowel function after right-sided colectomy are not well understood compared to those associated with left-sided colectomy or rectal resection.In particular,there are concerns about bowel function... BACKGROUND Changes in bowel function after right-sided colectomy are not well understood compared to those associated with left-sided colectomy or rectal resection.In particular,there are concerns about bowel function after right-sided colectomy with complete mesocolic excision,which has become popular in the West.AIM To evaluate the functional outcomes of patients who underwent right-sided colectomy with D3 lymphadenectomy for colon cancer.METHODS Functional data from patients who underwent minimally invasive right-sided colectomy for colon cancer from October 2017 to September 2018 were prospectively collected.Functional outcomes were evaluated preoperatively and at 3,6,12,and 18 mo postoperatively.RESULTS Prior to surgery,57 patients answered the questionnaire,and 47 responded at three months,52 at 6 mo,52 at 12 mo,and 25 at 18 mo postoperatively.Most scales of quality of life and bowel function improved significantly over time.Urgency persisted to a high degree throughout the period without a significant change over time.The use of medications for defecation was about 10%over the entire period.Gas(P=0.023)and fecal frequency(P<0.001)increased,and bowel dysfunction group(P=0.028)was more common among patients taking medication.At six months,resected bowel and colon lengths were significantly different as a risk factor between the dysfunction group and the no dysfunction group[odd ratio(OR):1.095,P=0.026;OR:1.147,P=0.031,respectively]in univariate analysis,but not in multivariate analysis.CONCLUSION Despite D3 lymphadenectomy,most bowel symptoms improved over time after right-sided colectomy using a minimally invasive approach,and continuous medication was needed in only approximately 10%of patients. 展开更多
关键词 Colonic neoplasm Right colectomy Bowel function d3 lymphadenectomy Complete mesocolic excision Quality of life
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Orthodontic treatment combined with 3D printing guide plate implant restoration for edentulism and its influence on mastication and phonic function 被引量:1
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作者 Li-Bo Yan Yu-Chao Zhou +1 位作者 Yang Wang Li-Xin Li 《World Journal of Clinical Cases》 SCIE 2022年第16期5297-5305,共9页
BACKGROUND Dentition defect,a common clinical oral disease developed in humans,not only causes masticatory dysfunction and articulation difficulties but also affects facial appearance and increases the burden on the i... BACKGROUND Dentition defect,a common clinical oral disease developed in humans,not only causes masticatory dysfunction and articulation difficulties but also affects facial appearance and increases the burden on the intestinal tract.Restorative treatment is the primary option for this disease.However,traditional restorations have many drawbacks,such as mismatch with the body,low reliability,and incomplete occlusal function recovery.AIM to analyze the efficacy of orthodontics combined with 3D printing guide plate implant restoration in treating patients with dentition defects and its influence on masticatory and phonic functions.METHODS A prospective study was carried out in 86 patients with dentition defects who received implant prosthesis after orthodontic treatment in our hospital between January 2018 and January 2019.Those patients were divided into a control group and an intervention group with 43 patients in each group using a random number table.The control group received traditional implant restoration,whereas the intervention group received 3D printing guide plate implant restoration.Treatment outcomes,cosmetic appearance,dental function,implant deviation,and quality of life were compared between the two groups.RESULTS The overall response rate in the intervention group was significantly higher than that in the control group(95.35%vs 81.40%,χ^(2)=4.071,P=0.044).The number of cases with neatly trimmed cosmetic appearance(χ^(2)=4.497,P=0.034),complete coverage(χ^(2)=4.170,P=0.041),and normal occlusion(χ^(2)=5.512,P=0.019)in the intervention group was higher than that in the control group.After treatment,mastication,swallowing,and articulation were significantly improved in both groups.Masticatory(t=2.980,P=0.004),swallowing(t=2.199,P=0.031),and phonic functions(t=3.950,P=0.004)were better in the intervention group than those in the control group.The deviation value and the deviation angle(t=5.440,P=0.000)at the top(t=6.320,P=0.000)and middle parts of the implants(t=22.295,P=0.000)in the intervention group were lower than those in the control group after treatment.Functional limitations,psychosocial and physical pain and discomfort,and total scores decreased in both groups.The functional limitation(t=2.379,P=0.020),psychosocial(t=2.420,P=0.000),physical pain and discomfort(t=6.581,P=0.000),and total scores(t=2.140,P=0.035)were lower in the intervention group than those in the control group.CONCLUSION Orthodontic treatment combined with 3D printing guide plate implant restoration can significantly improve the masticatory and phonic functions,quality of life,and psychological health of patients with dentition defects.Therefore,it is highly recommended in clinic application. 展开更多
关键词 dentition defect ORTHOdONTICS 3d printing guide plate implant restoration Masticatory function Phonic function
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ERK phosphorylation functions in invadopodia formation in tongue cancer cells in a novel silicate fibre-based 3D cell culture system 被引量:2
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作者 Masaharu Noi Ken-Ichi Mukaisho +8 位作者 Saori Yoshida Shoko Murakami Shinya Koshinuma Takeshi Adachi Yoshisato Machida Masashi Yamori Takahisa Nakayama Gaku Yamamoto Hiroyuki Sugihara 《International Journal of Oral Science》 SCIE CAS CSCD 2018年第4期253-262,共10页
To screen for additional treatment targets against tongue cancer, we evaluated the contributions of extracellular signal-related kinase(ERK), AKT and ezrin in cancer development. Immunohistochemical staining showed th... To screen for additional treatment targets against tongue cancer, we evaluated the contributions of extracellular signal-related kinase(ERK), AKT and ezrin in cancer development. Immunohistochemical staining showed that ERK and ezrin expressions were significantly higher in invasive squamous cell carcinoma than in carcinoma in situ. To investigate the roles of ERK and ezrin in cancer development, we used the non-woven silica fibre sheet Cellbedwith a structure resembling the loose connective tissue morphology in a novel 3 D culture system. We confirmed that the 3 D system using CellbedTMaccurately mimicked cancer cell morphology in vivo. Furthermore, cell projections were much more apparent in 3 D-cultured tongue cancer cell lines than in 2 D cultures. Typically, under conventional 2 D culture conditions, F-actin and cortactin are colocalized in the form of puncta within cells.However, in the 3 D-cultured cells, colocalization was mainly observed at the cell margins, including the projections. Projections containing F-actin and cortactin colocalization were predicted to be invadopodia. Although suppressing ezrin expression with small interfering RNA transfection caused no marked changes in morphology, cell projection formation was decreased, and the tumour thickness in vertical sections after 3 D culture was markedly decreased after suppressing ERK activity because both the invasion ability and proliferation were inhibited. An association between cortactin activation as well as ERK activity and invadopodia formation was detected. Our novel 3 D culture systems using Cellbed? are simple and useful for in vitro studies before conducting animal experiments. ERK contributes to tongue cancer development by increasing both cancer cell proliferation and migration via cortactin activation. 展开更多
关键词 ERK phosphorylation functions in invadopodia formation in tongue cancer cells in a novel silicate fibre-based 3d cell culture sy HSC
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3D analysis of functionally graded material plates with complex shapes and various holes
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作者 曹志远 唐寿高 程国华 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第1期13-18,共6页
In this paper, the basic formulae for the semi-analytical graded FEM on FGM members are derived. Since FGM parameters vary along three space coordinates, the parameters can be integrated in mechanical equations. There... In this paper, the basic formulae for the semi-analytical graded FEM on FGM members are derived. Since FGM parameters vary along three space coordinates, the parameters can be integrated in mechanical equations. Therefore with the parameters of a given FGM plate, problems of FGM plate under various conditions can be solved. The approach uses 1D discretization to obtain 3D solutions, which is proven to be an effective numerical method for the mechanical analyses of FGM structures. Examples of FGM plates with complex shapes and various holes are presented. 展开更多
关键词 functionally graded material semi-analytical method complex shape 3d analysis HOLE
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Static and dynamic stability responses of multilayer functionally graded carbon nanotubes reinforced composite nanoplates via quasi 3D nonlocal strain gradient theory
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作者 Ahmed Amine Daikh Mohamed Sid Ahmed Houari +2 位作者 Mohamed Ouejdi Belarbi Salwa A.Mohamed Mohamed A.Eltaher 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第10期1778-1809,共32页
This manuscript presents the comprehensive study of thickness stretching effects on the free vibration,static stability and bending of multilayer functionally graded(FG)carbon nanotubes reinforced composite(CNTRC)nano... This manuscript presents the comprehensive study of thickness stretching effects on the free vibration,static stability and bending of multilayer functionally graded(FG)carbon nanotubes reinforced composite(CNTRC)nanoplates.The nanoscale and microstructure influences are considered through a modified nonlocal strain gradient continuum model.Based on power-law functions,four different patterns of CNTs distribution are considered in this analysis,a uniform distribution UD,FG-V CNTRC,FG-X CNTRC,and FG-O CNTRC.A 3D kinematic shear deformation theory is proposed to include the stretching influence,which is neglected in classical theories.Hamilton's principle is applied to derive the governing equations of motion and associated boundary conditions.Analytical solutions are developed based on Galerkin method to solve the governing equilibrium equations based on the generalized higher-order shear deformation theory and the nonlocal strain gradient theory and get the static bending,buckling loads,and natural frequencies of nanoplates.Verification with previous works is presented.A detailed parametric analysis is carried out to highlight the impact of thickness stretching,length scale parameter(nonlocal),material scale parameter(gradient),CNTs distribution pattern,geometry of the plate,various boundary conditions and the total number of layers on the stresses,deformation,critical buckling loads and vibration frequencies.Many new results are also reported in the current study,which will serve as a benchmark for future research. 展开更多
关键词 3d shear deformation theory Free vibration Buckling Bending Galerkin method functionally graded nanotube Nonlocal strain gradient theory
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Effect of Motor Relearning Combined with t DCS on Motor Function of Lower Extremities and Gait in Patients with Cerebral Infarction and 3D Gait Analysis
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作者 Jing XU Su ZHENG +2 位作者 Yuanhong XU Lili JI Chao QUAN 《Medicinal Plant》 CAS 2022年第5期74-76,82,共4页
[Objectives]To observe the effect of motor relearning combined with transcranial direct current stimulation on the motor function of lower extremities in patients with cerebral infarction,and to observe its effect on ... [Objectives]To observe the effect of motor relearning combined with transcranial direct current stimulation on the motor function of lower extremities in patients with cerebral infarction,and to observe its effect on gait by 3D gait analysis.[Methods]60 patients with cerebral infarction who met the inclusion criteria were randomly divided into 3 groups according to the order of treatment(n=20).Group A received motor relearning treatment,group B received transcranial direct current stimulation treatment,group C received motor relearning combined with transcranial direct current stimulation,and the curative effect was observed after 5 courses of treatment.[Results]Before treatment,FMA,MBI,spatio-temporal parameters for 3D gait analysis(gait frequency,gait cycle,stride length,gait speed,stride length deviation,double support)and lower limb joint motion parameters(affected side stride length,maximum hip flexion,maximum hip extension,maximum knee flexion,maximum knee extension,stance phase,swing phase)were compared among the three groups.After treatment,the FMA and MBI of the three groups increased,and the spatio-temporal parameters for 3D gait analysis(gait frequency,gait cycle,gait speed,double support)and the lower limb joint motion parameters(affected side stride length,maximum hip flexion,maximum hip extension,maximum knee flexion,swing phase)were all improved,while the spatio-temporal parameters(stride length and stride length deviation)and the lower limb joint motion parameters(maximum knee extension and stance phase)decreased.Compared with those before treatment,there were significant differences among the three groups(P<0.05).Through the comparison between groups,it was found that the FMA,MBI,spatio-temporal parameters for 3D gait analysis(gait frequency,gait cycle,gait speed,double support)and lower limb joint motion parameters(affected side stride length,maximum hip flexion,maximum hip extension,maximum knee flexion,swing phase)in group C were significantly higher than those in group A and B,while the spatio-temporal parameters(stride length and stride length deviation)and lower limb joint motion parameters(maximum knee extension and stance phase)in group C were significantly lower than those in group A and group B,and the difference was statistically significant(P<0.05).[Conclusions]Motor relearning combined with transcranial direct current stimulation could increase MBI and FMA,improve gait spatio-temporal parameters and lower limb joint motion parameters,and correct abnormal gait in patients with cerebral infarction. 展开更多
关键词 Motor relearning Transcranial direct current stimulation Cerebral infarction Lower extremities Motor function 3d gait analysis
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血清25-羟维生素D_(3)水平对老年首发脑梗死患者卒中后认知功能的影响 被引量:7
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作者 陆珍辉 郭啸鸣 +3 位作者 李新玲 曹志勇 朱连海 朱向阳 《实用临床医药杂志》 CAS 2021年第17期61-66,共6页
目的探讨血清25-羟维生素D_(3)[25(OH)D_(3)]对老年首发脑梗死患者卒中后认知功能的影响。方法选取270例老年首发脑梗死患者作为研究对象,入院时评估美国国立卫生研究院卒中量表(NIHSS)评分、蒙特利尔认知量表(MoCA)评分,随访6个月,于3... 目的探讨血清25-羟维生素D_(3)[25(OH)D_(3)]对老年首发脑梗死患者卒中后认知功能的影响。方法选取270例老年首发脑梗死患者作为研究对象,入院时评估美国国立卫生研究院卒中量表(NIHSS)评分、蒙特利尔认知量表(MoCA)评分,随访6个月,于3个月时复测MoCA评分,6个月时评估改良Rankin量表(mRS)评分。根据3个月时MoCA评分将患者分为早期卒中后认知障碍(PSCI)组和早期卒中后认知正常(Non-PSCI)组,比较2组患者的临床资料;采用Logistic回归分析确定老年首发脑梗死患者早期PSCI的独立影响因素;绘制受试者工作特征(ROC)曲线评价血清25(OH)D_(3)水平对老年首发脑梗死患者早期PSCI的预测价值;根据血清25(OH)D_(3)截断值将患者分为低VD组与正常VD组,比较2组间早期PSCI发病率、MoCA评分差异。结果270例患者中,早期PSCI发病率高达60.37%(163/270)。血清25(OH)D_(3)水平(OR=0.834,95%CI为0.766~0.907,P<0.001)是老年首发急性脑梗死患者早期PSCI的独立影响因素,女性患者血清25(OH)D_(3)水平与脑梗死后早期认知功能的关联强度大于男性患者。血清25(OH)D_(3)预测老年首发脑梗死患者早期PSCI的ROC曲线下面积为0.751(P<0.05),最佳截断值为23.17 ng/mL。低VD组早期PSCI发病率高于正常VD组,MoCA评分低于正常VD组,差异有统计学意义(P<0.05)。结论正常水平血清25(OH)D_(3)是老年首发脑梗死患者早期PSCI的独立保护性因素。血清25(OH)D_(3)水平会影响老年首发脑梗死患者卒中后认知功能,且对老年女性卒中后认知功能的影响要大于老年男性。 展开更多
关键词 维生素d 25-羟维生素d_(3) 老年人 脑梗死 认知功能 卒中后认知障碍
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3D打印整体复制技术在脑动脉瘤手术治疗中的应用 被引量:5
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作者 王森 张洪兵 +5 位作者 原静 胡艳龙 杨俊 侯哲 康慧斌 黄庆 《中国临床神经外科杂志》 2020年第1期22-24,共3页
目的探讨3D打印整体复制技术在脑动脉瘤手术治疗中的应用价值。方法 2017年2月至2019年2月收治符合标准的脑动脉瘤54例,根据术前规划分为观察组(27例)和对照组(27例)。对照组按常规进行计划实施手术。观察组术前应用颅脑整体3D打印模型... 目的探讨3D打印整体复制技术在脑动脉瘤手术治疗中的应用价值。方法 2017年2月至2019年2月收治符合标准的脑动脉瘤54例,根据术前规划分为观察组(27例)和对照组(27例)。对照组按常规进行计划实施手术。观察组术前应用颅脑整体3D打印模型进行动脉瘤手术模拟。结果两组均顺利完成手术治疗。观察组术中显露时间[(123.3±74.9)min]显著短于对照组[(219.8±121.4)min,P<0.05]。两组住院时间无明显差异(P>0.05)。观察组术后6个月GOS评分[(4.33±0.25)分]、手术前后NIHSS评分差值[(5.85±3.84)分]、Barthrl指数差值[(17.50±4.56)分]均显著大于对照组[分别为(2.86±0.12)分、(3.30±3.53)分、(10.00±5.31)分;P<0.05]。两组术后并发症发生率无明显差异(P>0.05)。结论 3D整体打印模型辅助制定手术计划,可缩短脑动脉瘤术中显露时间,同时改善病人预后。 展开更多
关键词 脑动脉瘤 显微手术 3d打印技术 手术计划
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一类3--D非线性系统的稳定性分析及函数观测器设计 被引量:1
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作者 王璐 徐慧玲 《控制理论与应用》 EI CAS CSCD 北大核心 2014年第4期493-500,共8页
本文首先研究了一类3--D非线性系统的稳定性问题,在此基础上,利用秩条件和线性矩阵不等式(LMI)方法,得到了这类系统的渐近函数观测器存在的充分条件,并给出了函数观测器的设计方法.最后,通过算例来说明这种方法是可行且有效的.
关键词 3-d系统 非线性系统 LMI方法 函数观测器
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3-DJulia集和Mandelbrot集的生成模型 被引量:2
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作者 柳朝阳 《河南科学》 1995年第2期99-103,共5页
借助于复变函数理论,平面分形图得到了广泛的研究,借助于四维空间中的四无数,有了一些作为3一D子空间截面集的Julia集,但有很大的局限性。本文提出生成分形图函数的参数化模型,研究了3一D分形图的生成方法,揭示了这样生... 借助于复变函数理论,平面分形图得到了广泛的研究,借助于四维空间中的四无数,有了一些作为3一D子空间截面集的Julia集,但有很大的局限性。本文提出生成分形图函数的参数化模型,研究了3一D分形图的生成方法,揭示了这样生成的3一D分形图与平面分形图的联系,讨论了直接在三维空间中生成的3一DMandelbrot集的性质,同时也指出这种方法有更广泛的适用范围。 展开更多
关键词 3d JULIA集 MANdELBROT集 分形图 生成函数
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基于SVR学习的多源空间分布系统3-DFLC
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作者 张宪霞 秦磊 李佳佳 《系统仿真学报》 CAS CSCD 北大核心 2014年第10期2418-2422,2429,共6页
针对多控制源空间分布系统,提出了一种基于多输出支持向量回归机(SVR)学习的3-D模糊控制(3-D FLC)设计方法。基于多控制源空间分布系统的空间局部影响特性,将多控制源系统分解成多个单控制源子系统,每个子系统均采用单独的3-D FLC控制。... 针对多控制源空间分布系统,提出了一种基于多输出支持向量回归机(SVR)学习的3-D模糊控制(3-D FLC)设计方法。基于多控制源空间分布系统的空间局部影响特性,将多控制源系统分解成多个单控制源子系统,每个子系统均采用单独的3-D FLC控制。将3-D FLC的空间模糊基函数用作SVR的核函数,建立起3-D FLC与SVR的数学等价关系。用SVR学习隐含有控制规律的输入输出数据集,将学习后的支持向量作为关键数据点用来构建3-D FLC的模糊规则库,完成3-D FLC的设计。将该方法应用于填充床催化反应器温度控制,仿真结果验证了该方法的有效性。 展开更多
关键词 SVR 3-d FLC 空间分布系统 空间模糊基函数
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