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
This mini research explored effects of peer-scaffolding on EFL students through a collaborative oral task. In general,there are two research questions. The first one is: What kind of peer scaffolding behaviors can be ...This mini research explored effects of peer-scaffolding on EFL students through a collaborative oral task. In general,there are two research questions. The first one is: What kind of peer scaffolding behaviors can be reflected from the two participants? While the other is: How do these peer scaffolding behaviors affect or help EFL students to complete the collaborative oral task? From the research, 10 scaffolding behaviors were analyzed and classified into 5 aspects. Meanwhile, effects of peer-scaffolding can be investigated from 5 aspects mentioned above. In short, all the peer-scaffolding behaviors in this study play a positive role in helping two participants to complete the task.展开更多
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
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
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
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
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
As a major resource and tool of language learning, learner’s dictionaries have provided sufficient information forL2 writing, which serves as a good guide of peer feedback. Hence, learner’s dictionaries are an indis...As a major resource and tool of language learning, learner’s dictionaries have provided sufficient information forL2 writing, which serves as a good guide of peer feedback. Hence, learner’s dictionaries are an indispensable partof scaffolding in the L2 writing feedback system. However, the effects of dictionary use in L2 writing have longbeen ignored either in L2 writing pedagogy or in learner lexicography. By applying the concept of “scaffolding” topeer feedback as the theoretical framework, this study first clarifies three distinct types of scaffolding informationpresented in current English learner’s dictionaries, and then makes an investigation into EFL learners’ perceptionand practical use of scaffolding information in their English writing. Results show that most EFL learners havepositive attitudes towards scaffolding information and its role in motivating effective feedback in English writing.But their practical use of such information is not satisfactory owing to their inadequate skills and knowledge ofdictionary use. This reflects a high demand of a dictionary use course in universities, which will help to raise EFLlearners’ dictionary use efficiency as well as improve English teachers’ lexicographical expertise in English writingpedagogy.展开更多
This study aims to investigate the relationship between English Writing achievement and scaffolding instruction with 100 Students from Zuoyun high school as subjects in a quantitative method.Results show that:1)On the...This study aims to investigate the relationship between English Writing achievement and scaffolding instruction with 100 Students from Zuoyun high school as subjects in a quantitative method.Results show that:1)On the whole,high school students have good use of scaffolding in English writing.2)The application of scaffolding instruction in high school English writing teaching has a significant positive correlation with English writing performance.3)On the whole,there is a significant difference in the application of the scaffolds in English writing between high and low-score group students.展开更多
Traditional spoon-fed teaching in English classroom has exposed students to a trouble where they might lack enough collaborative experiences of language use in solving daily problems.In order to solve the problem,teac...Traditional spoon-fed teaching in English classroom has exposed students to a trouble where they might lack enough collaborative experiences of language use in solving daily problems.In order to solve the problem,teachers are facing the challenge of prompting peer interaction within a scaffold.So the question of how to improve students’awareness of collaboration in English classes has become the main focus of this article.It will try to discuss about the concept of peer scaffolding while at the same time,reflect on a detailed lesson plan which uses it to raise students’awareness to cooperate in problem solving.展开更多
Objective:To systematically evaluate the influence of scaffolding instruction on the learning effect of nursing students in China.Methods:Through the databases of CNKI,Wanfang,VIP,CBM,PubMed,Cochrane Library,Embase an...Objective:To systematically evaluate the influence of scaffolding instruction on the learning effect of nursing students in China.Methods:Through the databases of CNKI,Wanfang,VIP,CBM,PubMed,Cochrane Library,Embase and Web of Science,the randomized controlled trials of scaffolding instruction in nursing field were collected from the establishment of the databases to the publication in March 2022.After literature screening,data extraction and quality evaluation,meta-analysis was performed using RevMan5.3 and Stata16.0 software.Results:Nineteen articles were included,with a total of 2,340 nursing students.Meta-analysis results showed that,compared with the traditional teaching method,the scaffolding instruction was significantly better in nursing students’theoretical examination scores(SMD=1.37,95%CI:1.00 to 1.75,P<0.001),operation skill scores(SMD=1.83,95%CI:1.23 to 2.42,P<0.001),communication ability(SMD=1.51,95%CI:0.70 to 2.32,P=0.0003)and teaching satisfaction(P<0.05).Conclusion:Scaffolding instruction can improve the theoretical and operational scores of nursing students,and it also has a positive impact on communication ability and teaching satisfaction.This teaching method deserves to be applied and promoted in the field of nursing education.展开更多
This study measures the effectiveness of combining group discussions,pre-questionings,or both with scaffolding teaching strategies in translation lessons based on Angelelli's translation competence model.However,i...This study measures the effectiveness of combining group discussions,pre-questionings,or both with scaffolding teaching strategies in translation lessons based on Angelelli's translation competence model.However,in practice,the feasibility of using the Angelelli’s scoring scale to measure translation competence requires further verification by other empirical studies.The results of this study are only for reference,in hope that future researchers may contribute to the improvement in this subject.展开更多
Biomimetic materials have emerged as attractive and competitive alternatives for tissue engineering(TE)and regenerative medicine.In contrast to conventional biomaterials or synthetic materials,biomimetic scaffolds bas...Biomimetic materials have emerged as attractive and competitive alternatives for tissue engineering(TE)and regenerative medicine.In contrast to conventional biomaterials or synthetic materials,biomimetic scaffolds based on natural biomaterial can offer cells a broad spectrum of biochemical and biophysical cues that mimic the in vivo extracellular matrix(ECM).Additionally,such materials have mechanical adaptability,micro-structure interconnectivity,and inherent bioactivity,making them ideal for the design of living implants for specific applications in TE and regenerative medicine.This paper provides an overview for recent progress of biomimetic natural biomaterials(BNBMs),including advances in their preparation,functionality,potential applications and future challenges.We highlight recent advances in the fabrication of BNBMs and outline general strategies for functionalizing and tailoring the BNBMs with various biological and physicochemical characteristics of native ECM.Moreover,we offer an overview of recent key advances in the functionalization and applications of versatile BNBMs for TE applications.Finally,we conclude by offering our perspective on open challenges and future developments in this rapidly-evolving field.展开更多
In recent years,there has been considerable exploration into methods aimed at enhancing the regenerative capacity of transplanted and/or tissue-resident cells.Biomaterials,in particular,have garnered significant inter...In recent years,there has been considerable exploration into methods aimed at enhancing the regenerative capacity of transplanted and/or tissue-resident cells.Biomaterials,in particular,have garnered significant interest for their potential to serve as natural scaffolds for cells.In this editorial,we provide commentary on the study by Wang et al,in a recently published issue of World J Stem Cells,which investigates the use of a decellularized xenogeneic extracellular matrix(ECM)derived from antler stem cells for repairing osteochondral defects in rat knee joints.Our focus lies specifically on the crucial role of biological scaffolds as a strategy for augmenting stem cell potential and regenerative capabilities,thanks to the establishment of a favorable microenvironment(niche).Stem cell differen-tiation heavily depends on exposure to intrinsic properties of the ECM,including its chemical and protein composition,as well as the mechanical forces it can generate.Collectively,these physicochemical cues contribute to a bio-instructive signaling environment that offers tissue-specific guidance for achieving effective repair and regeneration.The interest in mechanobiology,often conceptualized as a form of“structural memory”,is steadily gaining more validation and momen-tum,especially in light of findings such as these.展开更多
Literature has shown that prior studies of educational"scaffolding"(a metaphor for"making connections betweennew situations and familiar ones"for students)focus on either teacher scaffolding for ch...Literature has shown that prior studies of educational"scaffolding"(a metaphor for"making connections betweennew situations and familiar ones"for students)focus on either teacher scaffolding for child learners or peer scaffoldingfor older learners.This paper,drawing on the findings and categories of prior researchers,conducted a research onscaffolding in adult ESL classrooms,from teachers as well as from peers.Following a qualitative approach that includes observation,audio-taping,transcription,collection of artifacts(handouts),and analysis,this paper has revealed the systematic distribution and applicability of scaffolding in adult ESL classrooms.Major findings are as follows.(1)Seven forms of teacher scaffolding(namely,modeling,offering explanations,invitingparticipation/contributions,clarifying/verifying understanding,simplifying the task.repeating/revoicing/restating,feedingback)and two forms of peer scaffolding(providing a word and providing an idea)are identified.(2)Within each form,scaffolds may occur at different levels.And one scaffolding talk may be multifunctional,serving several purposessimultaneously.(3)Very often in the data,explicit evidence of the learner’s achievement can be found,showing thepositive effect of the scaffolding talks in enhancing the student’s learning.(4)Which scaffolding form to employ dependson the interactions of such factors as the nature of the learning task,the language proficiency of the student,the culturalbackground of the student,the motivation of the student,and the availability of audio-visual or text materials,etc.Cultural misunderstandings should be avoided because they are counterforce to scaffolding and could be disastrous.展开更多
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
Microgels prepared from natural or synthetic hydrogel materials have aroused extensive attention as multifunctional cells or drug carriers,that are promising for tissue engineering and regenerative medicine.Microgels ...Microgels prepared from natural or synthetic hydrogel materials have aroused extensive attention as multifunctional cells or drug carriers,that are promising for tissue engineering and regenerative medicine.Microgels can also be aggregated into microporous scaffolds,promoting cell infiltration and proliferation for tissue repair.This review gives an overview of recent developments in the fabrication techniques and applications of microgels.A series of conventional and novel strategies including emulsification,microfluidic,lithography,electrospray,centrifugation,gas-shearing,three-dimensional bioprinting,etc.are discussed in depth.The characteristics and applications of microgels and microgel-based scaffolds for cell culture and delivery are elaborated with an emphasis on the advantages of these carriers in cell therapy.Additionally,we expound on the ongoing and foreseeable applications and current limitations of microgels and their aggregate in the field of biomedical engineering.Through stimulating innovative ideas,the present review paves new avenues for expanding the application of microgels in cell delivery techniques.展开更多
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
Traumatic brain injury is a serious medical condition that can be attributed to falls, motor vehicle accidents, sports injuries and acts of violence, causing a series of neural injuries and neuropsychiatric symptoms. ...Traumatic brain injury is a serious medical condition that can be attributed to falls, motor vehicle accidents, sports injuries and acts of violence, causing a series of neural injuries and neuropsychiatric symptoms. However, limited accessibility to the injury sites, complicated histological and anatomical structure, intricate cellular and extracellular milieu, lack of regenerative capacity in the native cells, vast variety of damage routes, and the insufficient time available for treatment have restricted the widespread application of several therapeutic methods in cases of central nervous system injury. Tissue engineering and regenerative medicine have emerged as innovative approaches in the field of nerve regeneration. By combining biomaterials, stem cells, and growth factors, these approaches have provided a platform for developing effective treatments for neural injuries, which can offer the potential to restore neural function, improve patient outcomes, and reduce the need for drugs and invasive surgical procedures. Biomaterials have shown advantages in promoting neural development, inhibiting glial scar formation, and providing a suitable biomimetic neural microenvironment, which makes their application promising in the field of neural regeneration. For instance, bioactive scaffolds loaded with stem cells can provide a biocompatible and biodegradable milieu. Furthermore, stem cells-derived exosomes combine the advantages of stem cells, avoid the risk of immune rejection, cooperate with biomaterials to enhance their biological functions, and exert stable functions, thereby inducing angiogenesis and neural regeneration in patients with traumatic brain injury and promoting the recovery of brain function. Unfortunately, biomaterials have shown positive effects in the laboratory, but when similar materials are used in clinical studies of human central nervous system regeneration, their efficacy is unsatisfactory. Here, we review the characteristics and properties of various bioactive materials, followed by the introduction of applications based on biochemistry and cell molecules, and discuss the emerging role of biomaterials in promoting neural regeneration. Further, we summarize the adaptive biomaterials infused with exosomes produced from stem cells and stem cells themselves for the treatment of traumatic brain injury. Finally, we present the main limitations of biomaterials for the treatment of traumatic brain injury and offer insights into their future potential.展开更多
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
基金Supported by 2017 Teaching Quality and Teaching Reform Project of Guizhou University of Traditional Chinese Medicine(3045-045170035)2018 School-level Undergraduate Teaching Engineering Construction Project of Guiyang College of Traditional Chinese Medicine(GZY-JG(2018)03)。
文摘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.
文摘This mini research explored effects of peer-scaffolding on EFL students through a collaborative oral task. In general,there are two research questions. The first one is: What kind of peer scaffolding behaviors can be reflected from the two participants? While the other is: How do these peer scaffolding behaviors affect or help EFL students to complete the collaborative oral task? From the research, 10 scaffolding behaviors were analyzed and classified into 5 aspects. Meanwhile, effects of peer-scaffolding can be investigated from 5 aspects mentioned above. In short, all the peer-scaffolding behaviors in this study play a positive role in helping two participants to complete the task.
文摘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.
文摘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.
文摘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.
文摘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.
文摘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.
文摘As a major resource and tool of language learning, learner’s dictionaries have provided sufficient information forL2 writing, which serves as a good guide of peer feedback. Hence, learner’s dictionaries are an indispensable partof scaffolding in the L2 writing feedback system. However, the effects of dictionary use in L2 writing have longbeen ignored either in L2 writing pedagogy or in learner lexicography. By applying the concept of “scaffolding” topeer feedback as the theoretical framework, this study first clarifies three distinct types of scaffolding informationpresented in current English learner’s dictionaries, and then makes an investigation into EFL learners’ perceptionand practical use of scaffolding information in their English writing. Results show that most EFL learners havepositive attitudes towards scaffolding information and its role in motivating effective feedback in English writing.But their practical use of such information is not satisfactory owing to their inadequate skills and knowledge ofdictionary use. This reflects a high demand of a dictionary use course in universities, which will help to raise EFLlearners’ dictionary use efficiency as well as improve English teachers’ lexicographical expertise in English writingpedagogy.
文摘This study aims to investigate the relationship between English Writing achievement and scaffolding instruction with 100 Students from Zuoyun high school as subjects in a quantitative method.Results show that:1)On the whole,high school students have good use of scaffolding in English writing.2)The application of scaffolding instruction in high school English writing teaching has a significant positive correlation with English writing performance.3)On the whole,there is a significant difference in the application of the scaffolds in English writing between high and low-score group students.
文摘Traditional spoon-fed teaching in English classroom has exposed students to a trouble where they might lack enough collaborative experiences of language use in solving daily problems.In order to solve the problem,teachers are facing the challenge of prompting peer interaction within a scaffold.So the question of how to improve students’awareness of collaboration in English classes has become the main focus of this article.It will try to discuss about the concept of peer scaffolding while at the same time,reflect on a detailed lesson plan which uses it to raise students’awareness to cooperate in problem solving.
文摘Objective:To systematically evaluate the influence of scaffolding instruction on the learning effect of nursing students in China.Methods:Through the databases of CNKI,Wanfang,VIP,CBM,PubMed,Cochrane Library,Embase and Web of Science,the randomized controlled trials of scaffolding instruction in nursing field were collected from the establishment of the databases to the publication in March 2022.After literature screening,data extraction and quality evaluation,meta-analysis was performed using RevMan5.3 and Stata16.0 software.Results:Nineteen articles were included,with a total of 2,340 nursing students.Meta-analysis results showed that,compared with the traditional teaching method,the scaffolding instruction was significantly better in nursing students’theoretical examination scores(SMD=1.37,95%CI:1.00 to 1.75,P<0.001),operation skill scores(SMD=1.83,95%CI:1.23 to 2.42,P<0.001),communication ability(SMD=1.51,95%CI:0.70 to 2.32,P=0.0003)and teaching satisfaction(P<0.05).Conclusion:Scaffolding instruction can improve the theoretical and operational scores of nursing students,and it also has a positive impact on communication ability and teaching satisfaction.This teaching method deserves to be applied and promoted in the field of nursing education.
文摘This study measures the effectiveness of combining group discussions,pre-questionings,or both with scaffolding teaching strategies in translation lessons based on Angelelli's translation competence model.However,in practice,the feasibility of using the Angelelli’s scoring scale to measure translation competence requires further verification by other empirical studies.The results of this study are only for reference,in hope that future researchers may contribute to the improvement in this subject.
基金supported by the National Natural Science Foundation of China(52003113,31900950,82102334,82002313,82072444)the National Key Research&Development Program of China(2018YFC2001502,2018YFB1105705)+6 种基金the Guangdong Basic and Applied Basic Research Foundation(2021A1515010745,2020A1515110356,2023A1515011986)the Shenzhen Fundamental Research Program(JCYJ20190808120405672)the Key Program of the National Natural Science Foundation of Zhejiang Province(LZ22C100001)the Natural Science Foundation of Shanghai(20ZR1469800)the Integration Innovation Fund of Shanghai Jiao Tong University(2021JCPT03),the Science and Technology Projects of Guangzhou City(202102020359)the Zigong Key Science and Technology Plan(2022ZCNKY07).SXC thanks the financial support under the Startup Grant of the University of Chinese Academy of Sciences(WIUCASQD2021026).HW thanks the Futian Healthcare Research Project(FTWS2022013)the financial support of China Postdoctoral Science Foundation(2021TQ0118).SL thanks the financial support of China Postdoctoral Science Foundation(2022M721490).
文摘Biomimetic materials have emerged as attractive and competitive alternatives for tissue engineering(TE)and regenerative medicine.In contrast to conventional biomaterials or synthetic materials,biomimetic scaffolds based on natural biomaterial can offer cells a broad spectrum of biochemical and biophysical cues that mimic the in vivo extracellular matrix(ECM).Additionally,such materials have mechanical adaptability,micro-structure interconnectivity,and inherent bioactivity,making them ideal for the design of living implants for specific applications in TE and regenerative medicine.This paper provides an overview for recent progress of biomimetic natural biomaterials(BNBMs),including advances in their preparation,functionality,potential applications and future challenges.We highlight recent advances in the fabrication of BNBMs and outline general strategies for functionalizing and tailoring the BNBMs with various biological and physicochemical characteristics of native ECM.Moreover,we offer an overview of recent key advances in the functionalization and applications of versatile BNBMs for TE applications.Finally,we conclude by offering our perspective on open challenges and future developments in this rapidly-evolving field.
文摘In recent years,there has been considerable exploration into methods aimed at enhancing the regenerative capacity of transplanted and/or tissue-resident cells.Biomaterials,in particular,have garnered significant interest for their potential to serve as natural scaffolds for cells.In this editorial,we provide commentary on the study by Wang et al,in a recently published issue of World J Stem Cells,which investigates the use of a decellularized xenogeneic extracellular matrix(ECM)derived from antler stem cells for repairing osteochondral defects in rat knee joints.Our focus lies specifically on the crucial role of biological scaffolds as a strategy for augmenting stem cell potential and regenerative capabilities,thanks to the establishment of a favorable microenvironment(niche).Stem cell differen-tiation heavily depends on exposure to intrinsic properties of the ECM,including its chemical and protein composition,as well as the mechanical forces it can generate.Collectively,these physicochemical cues contribute to a bio-instructive signaling environment that offers tissue-specific guidance for achieving effective repair and regeneration.The interest in mechanobiology,often conceptualized as a form of“structural memory”,is steadily gaining more validation and momen-tum,especially in light of findings such as these.
文摘Literature has shown that prior studies of educational"scaffolding"(a metaphor for"making connections betweennew situations and familiar ones"for students)focus on either teacher scaffolding for child learners or peer scaffoldingfor older learners.This paper,drawing on the findings and categories of prior researchers,conducted a research onscaffolding in adult ESL classrooms,from teachers as well as from peers.Following a qualitative approach that includes observation,audio-taping,transcription,collection of artifacts(handouts),and analysis,this paper has revealed the systematic distribution and applicability of scaffolding in adult ESL classrooms.Major findings are as follows.(1)Seven forms of teacher scaffolding(namely,modeling,offering explanations,invitingparticipation/contributions,clarifying/verifying understanding,simplifying the task.repeating/revoicing/restating,feedingback)and two forms of peer scaffolding(providing a word and providing an idea)are identified.(2)Within each form,scaffolds may occur at different levels.And one scaffolding talk may be multifunctional,serving several purposessimultaneously.(3)Very often in the data,explicit evidence of the learner’s achievement can be found,showing thepositive effect of the scaffolding talks in enhancing the student’s learning.(4)Which scaffolding form to employ dependson the interactions of such factors as the nature of the learning task,the language proficiency of the student,the culturalbackground of the student,the motivation of the student,and the availability of audio-visual or text materials,etc.Cultural misunderstandings should be avoided because they are counterforce to scaffolding and could be disastrous.
文摘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.
基金supported by the National Key Research and Development Program of China(No.2022YFA1104600)the National Natural Science Foundation of China(NSFC)Program(Nos.32201183,31927801,32101105)the Science and Technology Program of Guangzhou(SL2022A04J00774).
文摘Microgels prepared from natural or synthetic hydrogel materials have aroused extensive attention as multifunctional cells or drug carriers,that are promising for tissue engineering and regenerative medicine.Microgels can also be aggregated into microporous scaffolds,promoting cell infiltration and proliferation for tissue repair.This review gives an overview of recent developments in the fabrication techniques and applications of microgels.A series of conventional and novel strategies including emulsification,microfluidic,lithography,electrospray,centrifugation,gas-shearing,three-dimensional bioprinting,etc.are discussed in depth.The characteristics and applications of microgels and microgel-based scaffolds for cell culture and delivery are elaborated with an emphasis on the advantages of these carriers in cell therapy.Additionally,we expound on the ongoing and foreseeable applications and current limitations of microgels and their aggregate in the field of biomedical engineering.Through stimulating innovative ideas,the present review paves new avenues for expanding the application of microgels in cell delivery techniques.
基金The authors are thankful to Ministry of Human Resource Development(presently Ministry of Education),Government of India,New Delhi,for providing research facility by sanctioning Center of Excellence(F.No.5-6/2013-TS VII)in Tissue Engineering and Center of Excellence in Orthopedic Tissue Engineering and Rehabilitation funded by World Bank under TEQIP-II.
文摘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.
基金supported by the Sichuan Science and Technology Program,No.2023YFS0164 (to JC)。
文摘Traumatic brain injury is a serious medical condition that can be attributed to falls, motor vehicle accidents, sports injuries and acts of violence, causing a series of neural injuries and neuropsychiatric symptoms. However, limited accessibility to the injury sites, complicated histological and anatomical structure, intricate cellular and extracellular milieu, lack of regenerative capacity in the native cells, vast variety of damage routes, and the insufficient time available for treatment have restricted the widespread application of several therapeutic methods in cases of central nervous system injury. Tissue engineering and regenerative medicine have emerged as innovative approaches in the field of nerve regeneration. By combining biomaterials, stem cells, and growth factors, these approaches have provided a platform for developing effective treatments for neural injuries, which can offer the potential to restore neural function, improve patient outcomes, and reduce the need for drugs and invasive surgical procedures. Biomaterials have shown advantages in promoting neural development, inhibiting glial scar formation, and providing a suitable biomimetic neural microenvironment, which makes their application promising in the field of neural regeneration. For instance, bioactive scaffolds loaded with stem cells can provide a biocompatible and biodegradable milieu. Furthermore, stem cells-derived exosomes combine the advantages of stem cells, avoid the risk of immune rejection, cooperate with biomaterials to enhance their biological functions, and exert stable functions, thereby inducing angiogenesis and neural regeneration in patients with traumatic brain injury and promoting the recovery of brain function. Unfortunately, biomaterials have shown positive effects in the laboratory, but when similar materials are used in clinical studies of human central nervous system regeneration, their efficacy is unsatisfactory. Here, we review the characteristics and properties of various bioactive materials, followed by the introduction of applications based on biochemistry and cell molecules, and discuss the emerging role of biomaterials in promoting neural regeneration. Further, we summarize the adaptive biomaterials infused with exosomes produced from stem cells and stem cells themselves for the treatment of traumatic brain injury. Finally, we present the main limitations of biomaterials for the treatment of traumatic brain injury and offer insights into their future potential.
基金supported by the National Key R&D Program of China[grant number 2021YFC2400700]the National Natural Science Foundation of China[grant numbers 82170929,81970908 and 81771039].
文摘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.