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Insights into Nano-and Micro-Structured Scaffolds for Advanced Electrochemical Energy Storage 被引量:1
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作者 Jiajia Qiu Yu Duan +4 位作者 Shaoyuan Li Huaping Zhao Wenhui Ma Weidong Shi Yong Lei 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期187-230,共44页
Adopting a nano-and micro-structuring approach to fully unleashing the genuine potential of electrode active material benefits in-depth understandings and research progress toward higher energy density electrochemical... Adopting a nano-and micro-structuring approach to fully unleashing the genuine potential of electrode active material benefits in-depth understandings and research progress toward higher energy density electrochemical energy stor-age devices at all technology readiness levels.Due to various challenging issues,especially limited stability,nano-and micro-structured(NMS)electrodes undergo fast electrochemical performance degradation.The emerging NMS scaffold design is a pivotal aspect of many electrodes as it endows them with both robustness and electrochemical performance enhancement,even though it only occupies comple-mentary and facilitating components for the main mechanism.However,extensive efforts are urgently needed toward optimizing the stereoscopic geometrical design of NMS scaffolds to minimize the volume ratio and maximize their functionality to fulfill the ever-increasing dependency and desire for energy power source supplies.This review will aim at highlighting these NMS scaffold design strategies,summariz-ing their corresponding strengths and challenges,and thereby outlining the potential solutions to resolve these challenges,design principles,and key perspectives for future research in this field.Therefore,this review will be one of the earliest reviews from this viewpoint. 展开更多
关键词 Nano-and micro-structured Interconnected porous scaffolds Electrode design Electrochemical energy storage
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Discussion on Scaffolding Teaching Mode of Traditional Chinese Medicine under the Background of Internet
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作者 Ying MEI Fang CHEN +4 位作者 Ran ZHAO Ming LIU Dong LIU Zhibin JIANG Xiaogang LI 《Agricultural Biotechnology》 CAS 2023年第2期111-116,共6页
This study was conducted to explore the construction of scaffolding teaching mode of Traditional Chinese Medicine under the background of"Internet+".The students of Grade 2018 majoring in traditional Chinese... This study was conducted to explore the construction of scaffolding teaching mode of Traditional Chinese Medicine under the background of"Internet+".The students of Grade 2018 majoring in traditional Chinese medicine were selected as the object,and some chapters of the textbook of traditional Chinese medicine were selected and taught by the traditional teaching mode while interspersing the scaffolding teaching mode,in order to help the implementation of the scaffolding teaching model.We adopted the methods of setting up situational scaffolding,question scaffolding and guide scaffolding to carry out relevant teaching contents.The scaffolding instruction model has a good degree of participation,and to a certain extent,it stimulates students'self-consciousness and enthusiasm,and improves their ability of analyzing and solving problems and their spirit of innovation. 展开更多
关键词 Traditional Chinese medicine scaffolding teaching Internet+
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Customized scaffolds for large bone defects using 3D‑printed modular blocks from 2D‑medical images
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作者 Anil AAcar Evangelos Daskalakis +4 位作者 Paulo Bartolo Andrew Weightman Glen Cooper Gordon Blunn Bahattin Koc 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第1期74-87,共14页
Additive manufacturing(AM)has revolutionized the design and manufacturing of patient-specific,three-dimensional(3D),complex porous structures known as scaffolds for tissue engineering applications.The use of advanced ... Additive manufacturing(AM)has revolutionized the design and manufacturing of patient-specific,three-dimensional(3D),complex porous structures known as scaffolds for tissue engineering applications.The use of advanced image acquisition techniques,image processing,and computer-aided design methods has enabled the precise design and additive manufacturing of anatomically correct and patient-specific implants and scaffolds.However,these sophisticated techniques can be timeconsuming,labor-intensive,and expensive.Moreover,the necessary imaging and manufacturing equipment may not be readily available when urgent treatment is needed for trauma patients.In this study,a novel design and AM methods are proposed for the development of modular and customizable scaffold blocks that can be adapted to fit the bone defect area of a patient.These modular scaffold blocks can be combined to quickly form any patient-specific scaffold directly from two-dimensional(2D)medical images when the surgeon lacks access to a 3D printer or cannot wait for lengthy 3D imaging,modeling,and 3D printing during surgery.The proposed method begins with developing a bone surface-modeling algorithm that reconstructs a model of the patient’s bone from 2D medical image measurements without the need for expensive 3D medical imaging or segmentation.This algorithm can generate both patient-specific and average bone models.Additionally,a biomimetic continuous path planning method is developed for the additive manufacturing of scaffolds,allowing porous scaffold blocks with the desired biomechanical properties to be manufactured directly from 2D data or images.The algorithms are implemented,and the designed scaffold blocks are 3D printed using an extrusion-based AM process.Guidelines and instructions are also provided to assist surgeons in assembling scaffold blocks for the self-repair of patient-specific large bone defects. 展开更多
关键词 Additive manufacturing Modular scaffolds Large bone defect Customized scaffold design Patient-specific scaffolds
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Biological scaffold as potential platforms for stem cells:Current development and applications in wound healing
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作者 Jie-Yu Xiang Lin Kang +7 位作者 Zi-Ming Li Song-Lu Tseng Li-Quan Wang Tian-Hao Li Zhu-Jun Li Jiu-Zuo Huang Nan-Ze Yu Xiao Long 《World Journal of Stem Cells》 SCIE 2024年第4期334-352,共19页
Wound repair is a complex challenge for both clinical practitioners and researchers.Conventional approaches for wound repair have several limitations.Stem cell-based therapy has emerged as a novel strategy to address ... Wound repair is a complex challenge for both clinical practitioners and researchers.Conventional approaches for wound repair have several limitations.Stem cell-based therapy has emerged as a novel strategy to address this issue,exhibiting significant potential for enhancing wound healing rates,improving wound quality,and promoting skin regeneration.However,the use of stem cells in skin regeneration presents several challenges.Recently,stem cells and biomaterials have been identified as crucial components of the wound-healing process.Combination therapy involving the development of biocompatible scaffolds,accompanying cells,multiple biological factors,and structures resembling the natural extracellular matrix(ECM)has gained considerable attention.Biological scaffolds encompass a range of biomaterials that serve as platforms for seeding stem cells,providing them with an environment conducive to growth,similar to that of the ECM.These scaffolds facilitate the delivery and application of stem cells for tissue regeneration and wound healing.This article provides a comprehensive review of the current developments and applications of biological scaffolds for stem cells in wound healing,emphasizing their capacity to facilitate stem cell adhesion,proliferation,differentiation,and paracrine functions.Additionally,we identify the pivotal characteristics of the scaffolds that contribute to enhanced cellular activity. 展开更多
关键词 Stem-cell-based therapy Biological scaffolds Wound healing Extracellular matrix mimicry Cellular activities enhancement scaffold characteristics
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3D-printed Mg-1Ca/polycaprolactone composite scaffolds with promoted bone regeneration
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作者 Xiao Zhao Siyi Wang +6 位作者 Feilong Wang Yuan Zhu Ranli Gu Fan Yang Yongxiang Xu Dandan Xia Yunsong Liu 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期966-979,共14页
In bone tissue engineering,polycaprolactone(PCL)is a promising material with good biocompatibility,but its poor degradation rate,mechanical strength,and osteogenic properties limit its application.In this study,we dev... In bone tissue engineering,polycaprolactone(PCL)is a promising material with good biocompatibility,but its poor degradation rate,mechanical strength,and osteogenic properties limit its application.In this study,we developed an Mg-1Ca/polycaprolactone(Mg-1Ca/PCL)composite scaffolds to overcome these limitations.We used a melt blending method to prepare Mg-1Ca/PCL composites with Mg-1Ca alloy powder mass ratios of 5,10,and 20 wt%.Porous scaffolds with controlled macro-and microstructure were printed using the fused deposition modeling method.We explored the mechanical strength,biocompatibility,osteogenesis performance,and molecular mechanism of the Mg-1Ca/PCL composites.The 5 and 10 wt%Mg-1Ca/PCL composites were found to have good biocompatibility.Moreover,they promoted the mechanical strength,proliferation,adhesion,and osteogenic differentiation of human bone marrow stem cells(hBMSCs)of pure PCL.In vitro degradation experiments revealed that the composite material stably released Mg_(2)+ions for a long period;it formed an apatite layer on the surface of the scaffold that facilitated cell adhesion and growth.Microcomputed tomography and histological analysis showed that both 5 and 10 wt%Mg-1Ca/PCL composite scaffolds promoted bone regeneration bone defects.Our results indicated that the Wnt/β-catenin pathway was involved in the osteogenic effect.Therefore,Mg-1Ca/PCL composite scaffolds are expected to be a promising bone regeneration material for clinical application.Statement of significance:Bone tissue engineering scaffolds have promising applications in the regeneration of critical-sized bone defects.However,there remain many limitations in the materials and manufacturing methods used to fabricate scaffolds.This study shows that the developed Ma-1Ca/PCL composites provides scaffolds with suitable degradation rates and enhanced boneformation capabilities.Furthermore,the fused deposition modeling method allows precise control of the macroscopic morphology and microscopic porosity of the scaffold.The obtained porous scaffolds can significantly promote the regeneration of bone defects. 展开更多
关键词 3D printing Bone tissue engineering MAGNESIUM OSTEOGENIC POLYCAPROLACTONE scaffold.
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Constructing a biofunctionalized 3D-printed gelatin/sodium alginate/chitosan tri-polymer complex scaffold with improvised biological andmechanical properties for bone-tissue engineering
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作者 Amit Kumar Singh Krishna Pramanik Amit Biswas 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第1期57-73,共17页
Sodium alginate(SA)/chitosan(CH)polyelectrolyte scaffold is a suitable substrate for tissue-engineering application.The present study deals with further improvement in the tensile strength and biological properties of... Sodium alginate(SA)/chitosan(CH)polyelectrolyte scaffold is a suitable substrate for tissue-engineering application.The present study deals with further improvement in the tensile strength and biological properties of this type of scaffold to make it a potential template for bone-tissue regeneration.We experimented with adding 0%–15%(volume fraction)gelatin(GE),a protein-based biopolymer known to promote cell adhesion,proliferation,and differentiation.The resulting tri-polymer complex was used as bioink to fabricate SA/CH/GEmatrices by three-dimensional(3D)printing.Morphological studies using scanning electron microscopy revealed the microfibrous porous architecture of all the structures,which had a pore size range of 383–419μm.X-ray diffraction and Fourier-transform infrared spectroscopy analyses revealed the amorphous nature of the scaffold and the strong electrostatic interactions among the functional groups of the polymers,thereby forming polyelectrolyte complexes which were found to improve mechanical properties and structural stability.The scaffolds exhibited a desirable degradation rate,controlled swelling,and hydrophilic characteristics which are favorable for bone-tissue engineering.The tensile strength improved from(386±15)to(693±15)kPa due to the increased stiffness of SA/CH scaffolds upon addition of gelatin.The enhanced protein adsorption and in vitro bioactivity(forming an apatite layer)confirmed the ability of the SA/CH/GE scaffold to offer higher cellular adhesion and a bone-like environment to cells during the process of tissue regeneration.In vitro biological evaluation including the MTT assay,confocal microscopy analysis,and alizarin red S assay showed a significant increase in cell attachment,cell viability,and cell proliferation,which further improved biomineralization over the scaffold surface.In addition,SA/CH containing 15%gelatin designated as SA/CH/GE15 showed superior performance to the other fabricated 3D structures,demonstrating its potential for use in bone-tissue engineering. 展开更多
关键词 scaffold Biomaterial Sodium alginate CHITOSAN GELATIN 3D printing Tissue engineering
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In vitro investigations on the effects of graphene and graphene oxide on polycaprolactone bone tissue engineering scaffolds
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作者 Yanhao Hou Weiguang Wang Paulo Bartolo 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第5期651-669,共19页
Polycaprolactone(PCL)scaffolds that are produced through additive manufacturing are one of the most researched bone tissue engineering structures in the field.Due to the intrinsic limitations of PCL,carbon nanomateria... Polycaprolactone(PCL)scaffolds that are produced through additive manufacturing are one of the most researched bone tissue engineering structures in the field.Due to the intrinsic limitations of PCL,carbon nanomaterials are often investigated to reinforce the PCL scaffolds.Despite several studies that have been conducted on carbon nanomaterials,such as graphene(G)and graphene oxide(GO),certain challenges remain in terms of the precise design of the biological and nonbiological properties of the scaffolds.This paper addresses this limitation by investigating both the nonbiological(element composition,surface,degradation,and thermal and mechanical properties)and biological characteristics of carbon nanomaterial-reinforced PCL scaffolds for bone tissue engineering applications.Results showed that the incorporation of G and GO increased surface properties(reduced modulus and wettability),material crystallinity,crystallization temperature,and degradation rate.However,the variations in compressive modulus,strength,surface hardness,and cell metabolic activity strongly depended on the type of reinforcement.Finally,a series of phenomenological models were developed based on experimental results to describe the variations of scaffold’s weight,fiber diameter,porosity,and mechanical properties as functions of degradation time and carbon nanomaterial concentrations.The results presented in this paper enable the design of three-dimensional(3D)bone scaffolds with tuned properties by adjusting the type and concentration of different functional fillers. 展开更多
关键词 Additive manufacturing Bone tissue engineering Carbon nanomaterial GRAPHENE Graphene oxide scaffold
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Numerical Analysis of Permeability of Functionally Graded Scaffolds
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作者 Dmitry Bratsun Natalia Elenskaya +1 位作者 Ramil Siraev Mikhail Tashkinov 《Fluid Dynamics & Materials Processing》 EI 2024年第7期1463-1479,共17页
In this work,we numerically study the hydrodynamic permeability of new-generation artificial porous materials used as scaffolds for cell growth in a perfusion bioreactor.We consider two popular solid matrix designs ba... In this work,we numerically study the hydrodynamic permeability of new-generation artificial porous materials used as scaffolds for cell growth in a perfusion bioreactor.We consider two popular solid matrix designs based on triply periodic minimal surfaces,the Schwarz P(primitive)and D(diamond)surfaces,which enable the creation of materials with controlled porosity gradients.The latter property is crucial for regulating the shear stress field in the pores of the scaffold,which makes it possible to control the intensity of cell growth.The permeability of functionally graded materials is studied within the framework of both a microscopic approach based on the Navier-Stokes equation and an averaged description of the liquid filtration through a porous medium based on the equations of the Darcy or Forchheimer models.We calculate the permeability coefficients for both types of solid matrices formed by Schwarz surfaces,study their properties concerning forward and reverse fluid flows,and determine the ranges of Reynolds number for which the description within the Darcy or Forchheimer model is applicable.Finally,we obtain a shear stress field that varies along the sample,demonstrating the ability to tune spatially the rate of tissue growth. 展开更多
关键词 Porous media filtration models scaffolds functionally graded materials
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Oxygen vacancy boosting Fenton reaction in bone scaffold towards fighting bacterial infection
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作者 Cijun Shuai Xiaoxin Shi +2 位作者 Feng Yang Haifeng Tian Pei Feng 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期296-311,共16页
Bacterial infection is a major issue after artificial bone transplantation due to the absence of antibacterial function of bone scaffold,which seriously causes the transplant failure and even amputation in severe case... Bacterial infection is a major issue after artificial bone transplantation due to the absence of antibacterial function of bone scaffold,which seriously causes the transplant failure and even amputation in severe cases.In this study,oxygen vacancy(OV)defects Fe-doped Ti O2(OV-FeTiO2)nanoparticles were synthesized by nano TiO2and Fe3O4via high-energy ball milling,which was then incorporated into polycaprolactone/polyglycolic acid(PCLGA)biodegradable polymer matrix to construct composite bone scaffold with good antibacterial activities by selective laser sintering.The results indicated that OV defects were introduced into the core/shell-structured OV-FeTiO2nanoparticles through multiple welding and breaking during the high-energy ball milling,which facilitated the adsorption of hydrogen peroxide(H2O2)in the bacterial infection microenvironment at the bone transplant site.The accumulated H2O2could amplify the Fenton reaction efficiency to induce more hydroxyl radicals(·OH),thereby resulting in more bacterial deaths through·OH-mediated oxidative damage.This antibacterial strategy had more effective broad-spectrum antibacterial properties against Gram-negative Escherichia coli(E.coli)and Gram-positive Staphylococcus aureus(S.aureus).In addition,the PCLGA/OV-FeTiO2scaffold possessed mechanical properties that match those of human cancellous bone and good biocompatibility including cell attachment,proliferation and osteogenic differentiation. 展开更多
关键词 bacterial infection bone scaffold selective laser sintering Fenton reaction antibacterial properties
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Flame Retardant Material Based on Cellulose Scaffold Mineralized by Calcium Carbonate
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作者 Jinshuo Wang Lida Xing +1 位作者 Fulong Zhang Chuanfu Liu 《Journal of Renewable Materials》 EI CAS 2024年第1期89-102,共14页
Wood-based functional materials have developed rapidly.But the flammability significantly limits its further application.To improve the flame retardancy,the balsa wood was delignified by NaClO2 solution to create a ce... Wood-based functional materials have developed rapidly.But the flammability significantly limits its further application.To improve the flame retardancy,the balsa wood was delignified by NaClO2 solution to create a cellulose scaffold,and then alternately immersed in CaCl_(2) ethanol solution and NaHCO3 aqueous solution under vacuum.The high porosity and wettability resulting from delignification benefited the following mineralization process,changing the thermal properties of balsa wood significantly.The organic-inorganic wood composite showed abundant CaCO_(3) spherical particles under scanning electron microscopy.The peak of the heat release rate of delignified balsa-CaCO_(3) was reduced by 33%compared to the native balsa,according to the cone calorimetric characterization.The flame test demonstrated that the mineralized wood was flame retardant and selfextinguish.Additionally,the mineralized wood also displayed lower thermal conductivity.This study developed a feasible way to fabricate a lightweight,fire-retardant,self-extinguishing,and heat-insulating wood composite,providing a promising route for the valuable application of cellulosic biomass. 展开更多
关键词 Cellulose scaffold DELIGNIFICATION CaCO_(3) MINERALIZATION fire retardancy
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Advanced strategies for 3D-printed neural scaffolds:materials,structure,and nerve remodeling
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作者 Jian He Liang Qiao +5 位作者 Jiuhong Li Junlin Lu Zhouping Fu Jiafang Chen Xiangchun Zhang Xulin Hu 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第5期747-770,共24页
Nerve regeneration holds significant potential in the treatment of various skeletal and neurological disorders to restore lost sensory and motor functions.The potential of nerve regeneration in ameliorating neurologic... Nerve regeneration holds significant potential in the treatment of various skeletal and neurological disorders to restore lost sensory and motor functions.The potential of nerve regeneration in ameliorating neurological diseases and injuries is critical to human health.Three-dimensional(3D)printing offers versatility and precision in the fabrication of neural scaffolds.Complex neural structures such as neural tubes and scaffolds can be fabricated via 3Dprinting.This reviewcomprehensively analyzes the current state of 3D-printed neural scaffolds and explores strategies to enhance their design.It highlights therapeutic strategies and structural design involving neural materials and stem cells.First,nerve regeneration materials and their fabrication techniques are outlined.The applications of conductive materials in neural scaffolds are reviewed,and their potential to facilitate neural signal transmission and regeneration is highlighted.Second,the progress in 3D-printed neural scaffolds applied to the peripheral and central nerves is comprehensively evaluated,and their potential to restore neural function and promote the recovery of different nervous systems is emphasized.In addition,various applications of 3D-printed neural scaffolds in peripheral and neurological diseases,as well as the design strategies of multifunctional biomimetic scaffolds,are discussed. 展开更多
关键词 Nerve regeneration 3D printing based neural scaffolds BIOMATERIALS Nervous system Design strategies
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Enhanced axonal regeneration and functional recovery of the injured sciatic nerve in a rat model by lithium-loaded electrospun nanofibrous scaffolds
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作者 Banafsheh Dolatyar Bahman Zeynali +2 位作者 Iman Shabani Azita Parvaneh Tafreshi Reza Karimi-Soflou 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第5期701-720,共20页
Increasing evidence indicates that engineered nerve grafts have great potential for the regeneration of peripheral nerve injuries(PNIs).While most studies have focused only on the topographical features of the grafts,... Increasing evidence indicates that engineered nerve grafts have great potential for the regeneration of peripheral nerve injuries(PNIs).While most studies have focused only on the topographical features of the grafts,we have considered both the biophysical and biochemical manipulations in our applied nanoscaffold.To achieve this,we fabricated an electrospun nanofibrous scaffold(ENS)containing polylactide nanofibers loaded with lithium(Li)ions,a Wnt/β-catenin signaling activator.In addition,we seeded human adipose-derived mesenchymal stem cells(hADMSCs)onto this engineered scaffold to examine if their differentiation toward Schwann-like cells was induced.We further examined the efficacy of the scaffolds for nerve regeneration in vivo via grafting in a PNI rat model.Our results showed that Li-loaded ENSs gradually released Li within 11 d,at concentrations ranging from 0.02 to(3.64±0.10)mmol/L,and upregulated the expression of Wnt/β-catenin target genes(cyclinD1 and c-Myc)as well as those of Schwann cell markers(growth-associated protein 43(GAP43),S100 calcium binding protein B(S100B),glial fibrillary acidic protein(GFAP),and SRY-box transcription factor 10(SOX10))in differentiated hADMSCs.In the PNI rat model,implantation of Li-loaded ENSs with/without cells improved behavioral features such as sensory and motor functions as well as the electrophysiological characteristics of the injured nerve.This improved function was further validated by histological analysis of sciatic nerves grafted with Li-loaded ENSs,which showed no fibrous connective tissue but enhanced organized myelinated axons.The potential of Li-loaded ENSs in promoting Schwann cell differentiation of hADMSCs and axonal regeneration of injured sciatic nerves suggests their potential for application in peripheral nerve tissue engineering. 展开更多
关键词 Stem cell Schwann cell differentiation Electrospun nanofibrous scaffold Lithium ion Nerve regeneration
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Recognizing and preventing complications regarding bioresorbable scaffolds during coronary interventions
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作者 George Latsios Leonidas Koliastasis +1 位作者 Konstantinos Toutouzas Kostas Tsioufis 《World Journal of Cardiology》 2024年第9期508-511,共4页
The evolution of coronary intervention techniques and equipment has led to more sophisticated procedures for the treatment of highly complex lesions.However,as a result,the risk of complications has increased,which ar... The evolution of coronary intervention techniques and equipment has led to more sophisticated procedures for the treatment of highly complex lesions.However,as a result,the risk of complications has increased,which are mostly iatrogenic and often include equipment failure.Stent dislodgement warrants vigilance for the early diagnosis and a stepwise management approach is required to either expand or retrieve the lost stent.In the era of bioresorbable scaffolds that are not radiopaque,increased caution is required.Intravascular imaging may assist in detecting the lost scaffold in cases of no visibility fluoroscopically.Adequate lesion preparation is the key to minimizing the possibility of equipment loss;however,in the case that it occurs,commercially available and improvised devices and techniques may be applied. 展开更多
关键词 Bioresorbable scaffolds Stent dislodgement Complication prevention Coronary complications Equipment failure
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Ag-doped CNT/HAP nanohybrids in a PLLA bone scaffold show significant antibacterial activity
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作者 Cijun Shuai Xiaoxin Shi +3 位作者 Kai Wang Yulong Gu Feng Yang Pei Feng 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第2期105-120,共16页
Bacterial infection is a major problem following bone implant surgery.Moreover,poly-l-lactic acid/carbon nanotube/hydroxyapatite(PLLA/CNT/HAP)bone scaffolds possess enhanced mechanical properties and show good bioacti... Bacterial infection is a major problem following bone implant surgery.Moreover,poly-l-lactic acid/carbon nanotube/hydroxyapatite(PLLA/CNT/HAP)bone scaffolds possess enhanced mechanical properties and show good bioactiv-ityregardingbonedefectregeneration.Inthisstudy,wesynthesizedsilver(Ag)-dopedCNT/HAP(CNT/Ag-HAP)nanohybrids via the partial replacing of calcium ions(Ca2+)in the HAP lattice with silver ions(Ag+)using an ion doping technique under hydrothermal conditions.Specifically,the doping process was induced using the special lattice structure of HAP and the abundant surface oxygenic functional groups of CNT,and involved the partial replacement of Ca2+in the HAP lattice by doped Ag+as well as the in situ synthesis of Ag-HAP nanoparticles on CNT in a hydrothermal environment.The result-ing CNT/Ag-HAP nanohybrids were then introduced into a PLLA matrix via laser-based powder bed fusion(PBF-LB)to fabricate PLLA/CNT/Ag-HAP scaffolds that showed sustained antibacterial activity.We then found that Ag+,which pos-sesses broad-spectrum antibacterial activity,endowed PLLA/CNT/Ag-HAP scaffolds with this activity,with an antibacterial effectiveness of 92.65%.This antibacterial effect is due to the powerful effect of Ag+against bacterial structure and genetic material,as well as the physical destruction of bacterial structures due to the sharp edge structure of CNT.In addition,the scaffold possessed enhanced mechanical properties,showing tensile and compressive strengths of 8.49 MPa and 19.72 MPa,respectively.Finally,the scaffold also exhibited good bioactivity and cytocompatibility,including the ability to form apatite layers and to promote the adhesion and proliferation of human osteoblast-like cells(MG63 cells). 展开更多
关键词 Ag-doped Carbon nanotube/hydroxyapatite(CNT/HAP) Antibacterial properties Bone scaffold
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Application of Scaffolding Theory to Higher Vocational Students Classroom Interaction in English Teaching
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作者 罗晗 《海外英语》 2013年第12X期60-61,共2页
Scaffolding theory is one of the mature teaching methods of constructivism model . The effective interaction between teachers and students is one characteristic of scaffold teaching. This paper aims at combining scaff... Scaffolding theory is one of the mature teaching methods of constructivism model . The effective interaction between teachers and students is one characteristic of scaffold teaching. This paper aims at combining scaffolding theory with classroom interaction in teaching higher vocational students English to help students arouse interest and enhance their comprehensive ability in English learning. 展开更多
关键词 scaffolding THEORY CLASSROOM interaction HIGHER VO
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Effective Teaching and Learning: Scaffolding in Reading Class
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作者 岳宏艳 《海外英语》 2015年第22期287-288,共2页
This paper explores a teaching method—scaffolding in reading class, and also studies its background theories and proposes effective plans to carry out the scaffolding method. By this cooperative teaching and learning... This paper explores a teaching method—scaffolding in reading class, and also studies its background theories and proposes effective plans to carry out the scaffolding method. By this cooperative teaching and learning, students can not only complete teaching activities with the help of the teacher and students themselves, but also cultivate their abilities to use English and think critically. 展开更多
关键词 scaffolding READING PLAN
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The “Wrong Love” Between the Zone of Proximal Development and Scaffolding:An Interview With Prof.James P.Lantolf 被引量:8
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作者 Lili QIN 《Chinese Journal of Applied Linguistics》 2022年第1期138-149,152,共13页
The zone of proximal development(ZPD) and the scaffolding theory are very different,both in terms of their theoretical origins and connotations,and can even be said to be very different.However,during the development ... The zone of proximal development(ZPD) and the scaffolding theory are very different,both in terms of their theoretical origins and connotations,and can even be said to be very different.However,during the development of the two concepts,some scholars have misunderstood them,resulting in the two being mistaken for similar concepts and therefore often confused.Professor James Lantolf from Pennsylvania State University(State College,USA) was interviewed by Professor Lili Qin from Dalian University of Foreign Studies(Dalian,China) and provides an indepth analysis of these issues.The interview begins with the theoretical roots,connotations and definitions of the ZPD and scaffolding concepts,and then unravels the story of how they have been“mistakenly loved for life”,and ultimately it is made clear that the two concepts are completely different in their practical application to language teaching and should not continue to be used interchangeably. 展开更多
关键词 ZPD scaffolding Development INTERNALIZATION IMITATION
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Lexical Chunks as Scaffolding in College English Teaching
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作者 蒋素兰 《海外英语》 2012年第15期22-23,共2页
Lexical chunks minimize the language learners'burden of memorization and play a very important role in saving language pro cessing efforts so as to improve the learners'language fluency,appropriacy and idiomat... Lexical chunks minimize the language learners'burden of memorization and play a very important role in saving language pro cessing efforts so as to improve the learners'language fluency,appropriacy and idiomaticity.Lexical chunks are taken as"scaffolding"in college English teaching to effectively enhance learners'language proficiency. 展开更多
关键词 LEXICAL chunks scaffolding CHUNK COMPETENCE writin
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Undiscovered pathology of transient scaffolding remains a driver of failures in clinical trials
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作者 Alexander N Kharlamov 《World Journal of Cardiology》 CAS 2018年第10期165-186,共22页
AIM To statistically examine the released clinical trials and meta-analyses of polymeric bioresorbable scaffolds resuming the main accomplishments in the field with a translation to the routine clinical practice. METH... AIM To statistically examine the released clinical trials and meta-analyses of polymeric bioresorbable scaffolds resuming the main accomplishments in the field with a translation to the routine clinical practice. METHODS The statistical power in clinical trials such as ABSORB Japan, ABSORB China, EVERBIO II, AIDA, and few meta-analyses by the post hoc odds ratio-based sample size calculation, and the patterns of artery remodeling published in papers from ABSORB A and B trials were evaluated. RESULTS The phenomenal admiration from the first ABSORB studies in 2006-2013 was replaced by the tremendous disappointment in 2014-2017 due to reported relatively higher rates of target lesion failure(a mean prevalence of 9.16%) and device thrombosis(2.38%) in randomized controlled trials. Otherwise, bioresorbable vascular scaffold(BVS) performs as well as the metallic drugeluting stent(DES) with a trend toward some benefits for cardiac mortality [risk ratio(RR), 0.58-0.94, P > 0.05]. The underpowered design was confirmed for some studies such as ABSORB Japan, ABSORB China, EVERBIO Ⅱ, AIDA trials, and meta-analyses of Polimeni, Collet, and Mahmoud with some unintentional bias(judged by the asymmetrical Funnel plot). Scaffold thrombosis rates with Absorb BRS were comparable with DES performed with a so-called strategy of the BVS implantation with optimized pre-dilation(P), sizing(S) and post-dilation(P)(PSP) implantation(RR, PSP vs no PSP 0.37) achieving 0.35 per 100 patient-years, which is comparable to the RR 0.49 with bare-metal stents and the RR 1.06 with everolimus DES. Both ABSORB Ⅱ and ABSORB Ⅲ trials were powered enough for a five-year follow-up, but the results were not entirely conclusive due to the mostly non-significant fashion of data. The powered metaanalyses were built mostly on statistically poor findings. CONCLUSION The misunderstanding of the pathology of transient scaffolding drives the failures of the clinical trials. More bench studies of the vascular response are required. Several next-generation BVS including multifunctional electronic scaffold grant cardiology with a huge promise to make BVS technology great again. 展开更多
关键词 BIORESORBABLE scaffold Device THROMBOSIS Clinical outcomes Statistics INTRAVASCULAR imaging Arterial remodeling TRANSIENT scaffolding
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How to Promote Learner-Learner Scaffolding in ESL Classroom
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作者 周玥 《海外英语》 2016年第17期228-229,231,共3页
The current study attempts to investigate learner-learner scaffolding in ESL classroom.Analyzing how learners providing scaffolding with each other,and presenting methods how to promote learner-learner scaffolding.In ... The current study attempts to investigate learner-learner scaffolding in ESL classroom.Analyzing how learners providing scaffolding with each other,and presenting methods how to promote learner-learner scaffolding.In this paper,discourse analysis methodology utilized to carry out the research.In the study,the data collected from the transcripts of audio and video- recorded interaction during lessons in ESL classrooms at advanced level.The finding indicated that effective scaffolding among learners can promote their metacognition.It is hoped that the present study can serve to raise teachers' awareness of the importance of learner-learner scaffolding in English language teaching and learning. 展开更多
关键词 learner-learner scaffolding ESL classroom classroom interaction
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