With the development of information technology,the concept of smart healthcare has gradually come to the fore.Smart healthcare uses a new generation of information technologies,such as the internet of things(IoT),big ...With the development of information technology,the concept of smart healthcare has gradually come to the fore.Smart healthcare uses a new generation of information technologies,such as the internet of things(IoT),big data,cloud computing,and artificial intelligence,to transform the traditional medical system in an all-round way,making healthcare more efficient,more convenient,and more personalized.With the aim of introducing the concept of smart healthcare,in this review,we first list the key technologies that support smart healthcare and introduce the current status of smart healthcare in several important fields.Then we expound the existing problems with smart healthcare and try to propose solutions to them.Finally,we look ahead and evaluate the future prospects of smart healthcare.展开更多
Brachymeria lasus Walker is a solitary endoparasitoid that attacks the pupae of a wide range of lepidopteran hosts,including an important invasive species,the fall webworm(Hyphantria cunea Drury).We studied the relati...Brachymeria lasus Walker is a solitary endoparasitoid that attacks the pupae of a wide range of lepidopteran hosts,including an important invasive species,the fall webworm(Hyphantria cunea Drury).We studied the relationship between temperature and development of B.lasus from egg to adult hatching.The results show a decrease in parasitoid development time from 34.4 days at 18°C to 10.6 days at 32°C.The minimum threshold temperature of B.lasus was 13.2°C±1.7°C,and the eff ective accumulated temperature was 210.3±28.7 degree days.These results provide a basis for optimizing the production of this parasitoid.In addition,the eff ects of host size on off spring performance of B.lasus were investigated under laboratory conditions.Off spring longevity,size,and percentage of females were positively correlated with host size.Female off spring are larger and live longer than males.Furthermore,this research showed that parasitoid adults successfully emerged from approximately 27.9%of pupae.However,eclosion or hatching of H.cunea decreased dramatically,which may be due to damage caused by female B.lasus when testing hosts with their ovipositors or by feeding on them.The results suggest that B.lasus has the potential to become an effi cient natural enemy for controlling H.cunea.展开更多
This paper mainly explores the impact of export market diversification as an important measure to deal with trade friction on firms total factor productivity.Firstly,this article focuses on the theoretical analysis of...This paper mainly explores the impact of export market diversification as an important measure to deal with trade friction on firms total factor productivity.Firstly,this article focuses on the theoretical analysis of the impact mechanism,including risk diversification,reversal effect and spillover effect.Based on the sample data of Chinese manufacturing export enterprises from 2000 to 2007,this paper conducts an empirical test on the relationship between export market diversification and total factor productivity.The result indicates that export market diversification has a significant positive effect on the total factor productivity of enterprises.After considering the endogenous problem,by controlling the fixed effects,using the two-stage least square method and changing the duration of the sample for robustness analysis,the results are still consistent.In addition,the role of diversification policy in total factor productivity presents heterogeneous characteristics in terms of different types of enterprise ownership,export intensity,industry competition,trade methods,and the development degree of exporting market.Accordingly,this paper puts forward corresponding policy recommendations.展开更多
Taking the construction of new liberal arts as a background,this paper proposes that the international economy and trade major should optimize the teaching system and personnel training mechanism by adding the new cro...Taking the construction of new liberal arts as a background,this paper proposes that the international economy and trade major should optimize the teaching system and personnel training mechanism by adding the new cross-border e-commerce direction.This paper highlights the development path of high-quality international economy and trade professional training,and further ensures the first-class talent training and first-class professional construction specialty.展开更多
Tissue engineering is promising in realizing successful treatments of human body tissue loss that current methods cannot treat well or achieve satisfactory clinical outcomes.In scaffold-based bone tissue engineering,a...Tissue engineering is promising in realizing successful treatments of human body tissue loss that current methods cannot treat well or achieve satisfactory clinical outcomes.In scaffold-based bone tissue engineering,a high performance scaffold underpins the success of a bone tissue engineering strategy and a major direction in the field is to produce bone tissue engineering scaffolds with desirable shape,structural,physical,chemical and biological features for enhanced biological performance and for regenerating complex bone tissues.Three-dimensional(3D)printing can produce customized scaffolds that are highly desirable for bone tissue engineering.The enormous interest in 3D printing and 3D printed objects by the science,engineering and medical communities has led to various developments of the 3D printing technology and wide investigations of 3D printed products in many industries,including biomedical engineering,over the past decade.It is now possible to create novel bone tissue engineering scaffolds with customized shape,architecture,favorable macro-micro structure,wettability,mechanical strength and cellular responses.This article provides a concise review of recent advances in the R&D of 3D printing of bone tissue engineering scaffolds.It also presents our philosophy and research in the designing and fabrication of bone tissue engineering scaffolds through 3D printing.展开更多
Cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells contribute to the body's immune defenses. Current chimeric antigen receptor (CAR)-modified T cell immunotherapy shows strong promise for treating var...Cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells contribute to the body's immune defenses. Current chimeric antigen receptor (CAR)-modified T cell immunotherapy shows strong promise for treating var- ious cancers and infectious diseases. Although CAR- modified NK cell immunotherapy is rapidly gaining attention, its clinical applications are mainly focused on preclinical investigations using the NK92 cell line. Despite recent advances in CAR-modified T cell immunotherapy, cost and severe toxicity have hindered its widespread use. To alleviate these disadvantages of CAR-modified T cell immunotherapy, additional cyto- toxic cell-mediated immunotherapies are urgently nee- ded. The unique biology of NK cells allows them to serve as a safe, effective, alternative immunotherapeutic strategy to CAR-modified T cells in the clinic. While the fundamental mechanisms underlying the cytotoxicity and side effects of CAR-modified T and NK cell immunotherapies remain poorly understood, the for- mation of the immunological synapse (IS) between CAR- modified T or NK cells and their susceptible target cells is known to be essential. The role of the IS in CAR T and NK cell immunotherapies will allow scientists to harness the power of CAR-modified T and NK cells to treat can- cer and infectious diseases. In this review, we highlight the potential applications of CAR-modified NK cells to treat cancer and human immunodeficiency virus (HIV), and discuss the challenges and possible future directions of CAR-modified NK cell immunotherapy, as well as the importance of understanding the molecular mechanisms of CAR-modified T cell- or NK cell-medi- ated cytotoxicity and side effects, with a focus on the CAR-modified NK cell IS.展开更多
Tissue specificity,a key factor in the decellularized tissue matrix(DTM),has shown bioactive functionalities in tuning cell fate-e.g.,the differentiation of mesenchymal stem cells.Notably,cell fate is also determined ...Tissue specificity,a key factor in the decellularized tissue matrix(DTM),has shown bioactive functionalities in tuning cell fate-e.g.,the differentiation of mesenchymal stem cells.Notably,cell fate is also determined by the living microenvironment,including material composition and spatial characteristics.Herein,two neighboring tissues within intervertebral discs,the nucleus pulposus(NP)and annulus fibrosus(AF),were carefully processed into DTM hydrogels(abbreviated DNP-G and DAF-G,respectively)to determine the tissue-specific effects on stem cell fate,such as specific components and different culturing methods,as well as in vivo regeneration.Distinct differences in their protein compositions were identified by proteomic analysis.Interestingly,the fate of human bone marrow mesenchymal stem cells(hBMSCs)also responds to both culturing methods and composition.Generally,hBMSCs cultured with DNP-G(3D)differentiated into NP-like cells,while hBMSCs cultured with DAF-G(2D)underwent AF-like differentiation,indicating a close correlation with the native microenvironments of NP and AF cells,respectively.Furthermore,we found that the integrin-mediated RhoA/LATS/YAP1 signaling pathway was activated in DAF-G(2D)-induced AF-specific differentiation.Additionally,the activation of YAP1 determined the tendency of NP-or AF-specific differentiation and played opposite regulatory effects.Finally,DNP-G and DAF-G specifically promoted tissue regeneration in NP degeneration and AF defect rat models,respectively.In conclusion,DNP-G and DAF-G can specifically determine the fate of stem cells through the integrin-mediated RhoA/LATS/YAP1 signaling pathway,and this tissue specificity is both compositional and spatial,supporting the utilization of tissue-specific DTM in advanced treatments of intervertebral disc degeneration.展开更多
(Bi_(0.5)Na_(0.5))TiO_(3)(BNT)-based lead-free piezoceramics exhibit excellent electric field-induced strain(electrostrain)properties,but often suffer from large hysteresis and poor fatigue resistance,which strongly l...(Bi_(0.5)Na_(0.5))TiO_(3)(BNT)-based lead-free piezoceramics exhibit excellent electric field-induced strain(electrostrain)properties,but often suffer from large hysteresis and poor fatigue resistance,which strongly limit their applications.Here,<00l>textured Nb5+-doped 0.8(Bi_(0.5)Na_(0.5))TiO_(3)–0.2(Bi_(0.5)K_(0.5))TiO_(3)(0.8BNT–0.2BKT)ceramics with a high degree of texturing(~80%)were prepared by the reactive template grain growth(RTGG)method using Bi4Ti3O12 as a template.By the combination of donor doping in the B-site and the RTGG method,the electrostrain performance achieves a significant enhancement.A high electrostrain of 0.65%and a piezoelectric coefficient(*33 d)of 1083 pm/V with reduced hysteresis at an electric field of 6 kV/mm are obtained.No electrostrain performance degradation is observed after unipolar electric field loading of 10^(5)cycles,showing excellent fatigue endurance.These results indicate that the texturing BNT-based lead-free piezoceramics by the RTGG method is a useful approach to developing eco-friendly actuators.展开更多
The Extreme Learning Machine(ELM) and its variants are effective in many machine learning applications such as Imbalanced Learning(IL) or Big Data(BD) learning. However, they are unable to solve both imbalanced ...The Extreme Learning Machine(ELM) and its variants are effective in many machine learning applications such as Imbalanced Learning(IL) or Big Data(BD) learning. However, they are unable to solve both imbalanced and large-volume data learning problems. This study addresses the IL problem in BD applications. The Distributed and Weighted ELM(DW-ELM) algorithm is proposed, which is based on the Map Reduce framework. To confirm the feasibility of parallel computation, first, the fact that matrix multiplication operators are decomposable is illustrated.Then, to further improve the computational efficiency, an Improved DW-ELM algorithm(IDW-ELM) is developed using only one Map Reduce job. The successful operations of the proposed DW-ELM and IDW-ELM algorithms are finally validated through experiments.展开更多
Low back pain is a vital musculoskeletal disease that impairs life quality,leads to disability and imposes heavy economic burden on the society,while it is greatly attributed to intervertebral disc degeneration(IDD).H...Low back pain is a vital musculoskeletal disease that impairs life quality,leads to disability and imposes heavy economic burden on the society,while it is greatly attributed to intervertebral disc degeneration(IDD).However,the existing treatments,such as medicines,chiropractic adjustments and surgery,cannot achieve ideal disc regeneration.Therefore,advanced bioactive therapies are implemented,including stem cells delivery,bioreagents administration,and implantation of biomaterials etc.Among these researches,few reported unsatisfying regenerative outcomes.However,these advanced therapies have barely achieved successful clinical translation.The main reason for the inconsistency between satisfying preclinical results and poor clinical translation may largely rely on the animal models that cannot actually simulate the human disc degeneration.The inappropriate animal model also leads to difficulties in comparing the efficacies among biomaterials in different reaches.Therefore,animal models that better simulate the clinical charateristics of human IDD should be acknowledged.In addition,in vivo regenerative outcomes should be carefully evaluated to obtain robust results.Nevertheless,many researches neglect certain critical characteristics,such as adhesive properties for biomaterials blocking annulus fibrosus defects and hyperalgesia that is closely related to the clinical manifestations,e.g,low back pain.Herein,in this review,we summarized the animal models established for IDD,and highlighted the proper models and parameters that may result in acknowledged IDD models.Then,we discussed the existing biomaterials for disc regeneration and the characteristics that should be considered for regenerating different parts of discs.Finally,well-established assays and parameters for in vivo disc regeneration are explored.展开更多
The development of tissue engineering has led to new strategies for mitigating clinical problems;however,the design of the tissue engineering materials remains a challenge.The limited sources and inadequate function,p...The development of tissue engineering has led to new strategies for mitigating clinical problems;however,the design of the tissue engineering materials remains a challenge.The limited sources and inadequate function,potential risk of microbial or pathogen contamination,and high cost of cell expansion impair the efficacy and limit the application of exogenous cells in tissue engineering.However,endogenous cells in native tissues have been reported to be capable of spontaneous repair of the damaged tissue.These cells exhibit remarkable plasticity,and thus can differentiate or be reprogrammed to alter their phenotype and function after stimulation.After a comprehensive review,we found that the plasticity of these cells plays a major role in establishing the cell source in the mechanism involved in tissue regeneration.Tissue engineering materials that focus on assisting and promoting the natural self-repair function of endogenous cells may break through the limitations of exogenous seed cells and further expand the applications of tissue engineering materials in tissue repair.This review discusses the effects of endogenous cells,especially stem cells,on injured tissue repairing,and highlights the potential utilisation of endogenous repair in orthopaedic biomaterial constructions for bone,cartilage,and intervertebral disc regeneration.展开更多
Event-based computation has recently gained increasing research interest for applications of vision recogni-tion due to its intrinsic advantages on efficiency and speed.However,the existing event-based models for visi...Event-based computation has recently gained increasing research interest for applications of vision recogni-tion due to its intrinsic advantages on efficiency and speed.However,the existing event-based models for vision recogni-tion are faced with several issues,such as large network complexity and expensive training cost.In this paper,we propose an improved multi-liquid state machine(M-LSM)method for high-performance vision recognition.Specifically,we intro-duce two methods,namely multi-state fusion and multi-liquid search,to optimize the liquid state machine(LSM).Multi-state fusion by sampling the liquid state at multiple timesteps could reserve richer spatiotemporal information.We adapt network architecture search(NAS)to find the potential optimal architecture of the multi-liquid state machine.We also train the M-LSM through an unsupervised learning rule spike-timing dependent plasticity(STDP).Our M-LSM is evalu-ated on two event-based datasets and demonstrates state-of-the-art recognition performance with superior advantages on network complexity and training cost.展开更多
Hypertension is a worldwide health problem and a primary risk factor for cardiovascular disease.Continuous monitoring of blood pressure has important clinical value for the early diagnosis and prevention of cardiovasc...Hypertension is a worldwide health problem and a primary risk factor for cardiovascular disease.Continuous monitoring of blood pressure has important clinical value for the early diagnosis and prevention of cardiovascular disease.However,existing technologies for wearable continuous blood pressure monitoring are usually inaccurate,rely on subject-specific calibration and have poor generalization across individuals,which limit their practical applications.Here,we report a new blood pressure measurement method and develop an associated wearable device to implement continuous blood pressure monitoring for new subjects.The wearable device detects cardiac output and pulse waveform features through dual photoplethysmography(PPG)sensors worn on the palmar and dorsal sides of the wrist,incorporating custom-made interface sensors to detect the wearing contact pressure and skin temperature.The detected multichannel signals are fused using a machine-learning algorithm to estimate continuous blood pressure in real time.This dual PPG sensing method effectively eliminates the personal differences in PPG signals caused by different people and different wearing conditions.The proposed wearable device enables continuous blood pressure monitoring with good generalizability across individuals and demonstrates promising potential in personal health care applications.展开更多
The authors regret missing out the below change in the acknowledgment section of the article.The original sentence reads as"This work was supported by the Major Research Plan of National Natural Science Foundatio...The authors regret missing out the below change in the acknowledgment section of the article.The original sentence reads as"This work was supported by the Major Research Plan of National Natural Science Foundation of China[No.91649204],the National Key Research and Development Program of China[2016YFC1100100],…"and the same has been corrected to"This work was supported by the National Key Research and Development Program of China[2016YFC1100100],the Major Research Plan of National Natural Science Foundation of China[No.91649204],…"and the same has been corrected to"This work was supported by the National Key Research and Development Program of China[2016YFC1100100],the Major Research Plan of National Natural Science Foundation of China[No.91649204],…".展开更多
文摘With the development of information technology,the concept of smart healthcare has gradually come to the fore.Smart healthcare uses a new generation of information technologies,such as the internet of things(IoT),big data,cloud computing,and artificial intelligence,to transform the traditional medical system in an all-round way,making healthcare more efficient,more convenient,and more personalized.With the aim of introducing the concept of smart healthcare,in this review,we first list the key technologies that support smart healthcare and introduce the current status of smart healthcare in several important fields.Then we expound the existing problems with smart healthcare and try to propose solutions to them.Finally,we look ahead and evaluate the future prospects of smart healthcare.
基金the National Key R&D Program of China(2018YFC1200400)the research and innovation project for College Graduates of Jiangsu Province(KYLX18_0957).
文摘Brachymeria lasus Walker is a solitary endoparasitoid that attacks the pupae of a wide range of lepidopteran hosts,including an important invasive species,the fall webworm(Hyphantria cunea Drury).We studied the relationship between temperature and development of B.lasus from egg to adult hatching.The results show a decrease in parasitoid development time from 34.4 days at 18°C to 10.6 days at 32°C.The minimum threshold temperature of B.lasus was 13.2°C±1.7°C,and the eff ective accumulated temperature was 210.3±28.7 degree days.These results provide a basis for optimizing the production of this parasitoid.In addition,the eff ects of host size on off spring performance of B.lasus were investigated under laboratory conditions.Off spring longevity,size,and percentage of females were positively correlated with host size.Female off spring are larger and live longer than males.Furthermore,this research showed that parasitoid adults successfully emerged from approximately 27.9%of pupae.However,eclosion or hatching of H.cunea decreased dramatically,which may be due to damage caused by female B.lasus when testing hosts with their ovipositors or by feeding on them.The results suggest that B.lasus has the potential to become an effi cient natural enemy for controlling H.cunea.
基金This paper was supported by Shandong Provincial Social Science Research Project(16DJJJ03)“Comparative Study on the Effect of Introducing Market-oriented FDI and Import Trade on Promoting Economic Performance Improvement in Shandong Province”(16DJJJ03).
文摘This paper mainly explores the impact of export market diversification as an important measure to deal with trade friction on firms total factor productivity.Firstly,this article focuses on the theoretical analysis of the impact mechanism,including risk diversification,reversal effect and spillover effect.Based on the sample data of Chinese manufacturing export enterprises from 2000 to 2007,this paper conducts an empirical test on the relationship between export market diversification and total factor productivity.The result indicates that export market diversification has a significant positive effect on the total factor productivity of enterprises.After considering the endogenous problem,by controlling the fixed effects,using the two-stage least square method and changing the duration of the sample for robustness analysis,the results are still consistent.In addition,the role of diversification policy in total factor productivity presents heterogeneous characteristics in terms of different types of enterprise ownership,export intensity,industry competition,trade methods,and the development degree of exporting market.Accordingly,this paper puts forward corresponding policy recommendations.
基金supported by Laboratory construction project of Shandong University of Technology"Cross border e-commerce B2C platform product operation simulation experiment construction"(2020018).
文摘Taking the construction of new liberal arts as a background,this paper proposes that the international economy and trade major should optimize the teaching system and personnel training mechanism by adding the new cross-border e-commerce direction.This paper highlights the development path of high-quality international economy and trade professional training,and further ensures the first-class talent training and first-class professional construction specialty.
基金This work was supported by Dongguan University of Technology High-level Talents(Innovation Team)Research Project(KCYCXPT201603)Youth Innovative Talent Project from the Department of Education of Guangdong Province,China(2016KQNCX168)Natural Science Foundation of Guangdong Province,China(2018A0303130019).
文摘Tissue engineering is promising in realizing successful treatments of human body tissue loss that current methods cannot treat well or achieve satisfactory clinical outcomes.In scaffold-based bone tissue engineering,a high performance scaffold underpins the success of a bone tissue engineering strategy and a major direction in the field is to produce bone tissue engineering scaffolds with desirable shape,structural,physical,chemical and biological features for enhanced biological performance and for regenerating complex bone tissues.Three-dimensional(3D)printing can produce customized scaffolds that are highly desirable for bone tissue engineering.The enormous interest in 3D printing and 3D printed objects by the science,engineering and medical communities has led to various developments of the 3D printing technology and wide investigations of 3D printed products in many industries,including biomedical engineering,over the past decade.It is now possible to create novel bone tissue engineering scaffolds with customized shape,architecture,favorable macro-micro structure,wettability,mechanical strength and cellular responses.This article provides a concise review of recent advances in the R&D of 3D printing of bone tissue engineering scaffolds.It also presents our philosophy and research in the designing and fabrication of bone tissue engineering scaffolds through 3D printing.
文摘Cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells contribute to the body's immune defenses. Current chimeric antigen receptor (CAR)-modified T cell immunotherapy shows strong promise for treating var- ious cancers and infectious diseases. Although CAR- modified NK cell immunotherapy is rapidly gaining attention, its clinical applications are mainly focused on preclinical investigations using the NK92 cell line. Despite recent advances in CAR-modified T cell immunotherapy, cost and severe toxicity have hindered its widespread use. To alleviate these disadvantages of CAR-modified T cell immunotherapy, additional cyto- toxic cell-mediated immunotherapies are urgently nee- ded. The unique biology of NK cells allows them to serve as a safe, effective, alternative immunotherapeutic strategy to CAR-modified T cells in the clinic. While the fundamental mechanisms underlying the cytotoxicity and side effects of CAR-modified T and NK cell immunotherapies remain poorly understood, the for- mation of the immunological synapse (IS) between CAR- modified T or NK cells and their susceptible target cells is known to be essential. The role of the IS in CAR T and NK cell immunotherapies will allow scientists to harness the power of CAR-modified T and NK cells to treat can- cer and infectious diseases. In this review, we highlight the potential applications of CAR-modified NK cells to treat cancer and human immunodeficiency virus (HIV), and discuss the challenges and possible future directions of CAR-modified NK cell immunotherapy, as well as the importance of understanding the molecular mechanisms of CAR-modified T cell- or NK cell-medi- ated cytotoxicity and side effects, with a focus on the CAR-modified NK cell IS.
基金This work was supported by the Major Research Plan of National Natural Science Foundation of China[No.91649204]the National Key Research and Development Program of China[2016YFC1100100]the Scientific Research Training Program for Young Talents from Union Hospital,Tongji Medical College,Huazhong University of Science and Technology,National Natural Science Foundation of China(82002333)。
文摘Tissue specificity,a key factor in the decellularized tissue matrix(DTM),has shown bioactive functionalities in tuning cell fate-e.g.,the differentiation of mesenchymal stem cells.Notably,cell fate is also determined by the living microenvironment,including material composition and spatial characteristics.Herein,two neighboring tissues within intervertebral discs,the nucleus pulposus(NP)and annulus fibrosus(AF),were carefully processed into DTM hydrogels(abbreviated DNP-G and DAF-G,respectively)to determine the tissue-specific effects on stem cell fate,such as specific components and different culturing methods,as well as in vivo regeneration.Distinct differences in their protein compositions were identified by proteomic analysis.Interestingly,the fate of human bone marrow mesenchymal stem cells(hBMSCs)also responds to both culturing methods and composition.Generally,hBMSCs cultured with DNP-G(3D)differentiated into NP-like cells,while hBMSCs cultured with DAF-G(2D)underwent AF-like differentiation,indicating a close correlation with the native microenvironments of NP and AF cells,respectively.Furthermore,we found that the integrin-mediated RhoA/LATS/YAP1 signaling pathway was activated in DAF-G(2D)-induced AF-specific differentiation.Additionally,the activation of YAP1 determined the tendency of NP-or AF-specific differentiation and played opposite regulatory effects.Finally,DNP-G and DAF-G specifically promoted tissue regeneration in NP degeneration and AF defect rat models,respectively.In conclusion,DNP-G and DAF-G can specifically determine the fate of stem cells through the integrin-mediated RhoA/LATS/YAP1 signaling pathway,and this tissue specificity is both compositional and spatial,supporting the utilization of tissue-specific DTM in advanced treatments of intervertebral disc degeneration.
基金supported by the National Natural Science Foundation of China(52172135)the Youth Top Talent Project of the National“Ten Thousand Talents Program”(2021-527-07)the Guangdong Basic and Applied Basic Research Foundation for Distinguished Young Scholars(2021B1515020083 and 2022B1515020070).
文摘(Bi_(0.5)Na_(0.5))TiO_(3)(BNT)-based lead-free piezoceramics exhibit excellent electric field-induced strain(electrostrain)properties,but often suffer from large hysteresis and poor fatigue resistance,which strongly limit their applications.Here,<00l>textured Nb5+-doped 0.8(Bi_(0.5)Na_(0.5))TiO_(3)–0.2(Bi_(0.5)K_(0.5))TiO_(3)(0.8BNT–0.2BKT)ceramics with a high degree of texturing(~80%)were prepared by the reactive template grain growth(RTGG)method using Bi4Ti3O12 as a template.By the combination of donor doping in the B-site and the RTGG method,the electrostrain performance achieves a significant enhancement.A high electrostrain of 0.65%and a piezoelectric coefficient(*33 d)of 1083 pm/V with reduced hysteresis at an electric field of 6 kV/mm are obtained.No electrostrain performance degradation is observed after unipolar electric field loading of 10^(5)cycles,showing excellent fatigue endurance.These results indicate that the texturing BNT-based lead-free piezoceramics by the RTGG method is a useful approach to developing eco-friendly actuators.
基金partially supported by the National Natural Science Foundation of China(Nos.61402089,61472069,and 61501101)the Fundamental Research Funds for the Central Universities(Nos.N161904001,N161602003,and N150408001)+2 种基金the Natural Science Foundation of Liaoning Province(No.2015020553)the China Postdoctoral Science Foundation(No.2016M591447)the Postdoctoral Science Foundation of Northeastern University(No.20160203)
文摘The Extreme Learning Machine(ELM) and its variants are effective in many machine learning applications such as Imbalanced Learning(IL) or Big Data(BD) learning. However, they are unable to solve both imbalanced and large-volume data learning problems. This study addresses the IL problem in BD applications. The Distributed and Weighted ELM(DW-ELM) algorithm is proposed, which is based on the Map Reduce framework. To confirm the feasibility of parallel computation, first, the fact that matrix multiplication operators are decomposable is illustrated.Then, to further improve the computational efficiency, an Improved DW-ELM algorithm(IDW-ELM) is developed using only one Map Reduce job. The successful operations of the proposed DW-ELM and IDW-ELM algorithms are finally validated through experiments.
基金supported by the Major Research Plan of National Natural Science Foundation of China(No.91649204)the National Key Research and Development Program of China(No.2016YFC1100100)+2 种基金the National Natural Science Foundation of China(No.81974352)the Scientific Research Training Program for Young Talents from Union Hospital,Tongji Medical College,Huazhong University of Science and Technology,National Natural Science Foundation of China(No.82002333)Zhejiang Provincial Natural Science Foundation of China(No.LQ21H060004).
文摘Low back pain is a vital musculoskeletal disease that impairs life quality,leads to disability and imposes heavy economic burden on the society,while it is greatly attributed to intervertebral disc degeneration(IDD).However,the existing treatments,such as medicines,chiropractic adjustments and surgery,cannot achieve ideal disc regeneration.Therefore,advanced bioactive therapies are implemented,including stem cells delivery,bioreagents administration,and implantation of biomaterials etc.Among these researches,few reported unsatisfying regenerative outcomes.However,these advanced therapies have barely achieved successful clinical translation.The main reason for the inconsistency between satisfying preclinical results and poor clinical translation may largely rely on the animal models that cannot actually simulate the human disc degeneration.The inappropriate animal model also leads to difficulties in comparing the efficacies among biomaterials in different reaches.Therefore,animal models that better simulate the clinical charateristics of human IDD should be acknowledged.In addition,in vivo regenerative outcomes should be carefully evaluated to obtain robust results.Nevertheless,many researches neglect certain critical characteristics,such as adhesive properties for biomaterials blocking annulus fibrosus defects and hyperalgesia that is closely related to the clinical manifestations,e.g,low back pain.Herein,in this review,we summarized the animal models established for IDD,and highlighted the proper models and parameters that may result in acknowledged IDD models.Then,we discussed the existing biomaterials for disc regeneration and the characteristics that should be considered for regenerating different parts of discs.Finally,well-established assays and parameters for in vivo disc regeneration are explored.
基金supported by the National Key Research and Development Program of China(No.2016YFC1100100)the Major Research Plan of the National Natural Science Foundation of China(No.91649204)+1 种基金China Postdoctoral Science Foundation(No.2021M701331)the Scientific Research Training Program for Young Talents from Union Hospital,Tongji Medical College,Huazhong University of Science and Technology,China.
文摘The development of tissue engineering has led to new strategies for mitigating clinical problems;however,the design of the tissue engineering materials remains a challenge.The limited sources and inadequate function,potential risk of microbial or pathogen contamination,and high cost of cell expansion impair the efficacy and limit the application of exogenous cells in tissue engineering.However,endogenous cells in native tissues have been reported to be capable of spontaneous repair of the damaged tissue.These cells exhibit remarkable plasticity,and thus can differentiate or be reprogrammed to alter their phenotype and function after stimulation.After a comprehensive review,we found that the plasticity of these cells plays a major role in establishing the cell source in the mechanism involved in tissue regeneration.Tissue engineering materials that focus on assisting and promoting the natural self-repair function of endogenous cells may break through the limitations of exogenous seed cells and further expand the applications of tissue engineering materials in tissue repair.This review discusses the effects of endogenous cells,especially stem cells,on injured tissue repairing,and highlights the potential utilisation of endogenous repair in orthopaedic biomaterial constructions for bone,cartilage,and intervertebral disc regeneration.
基金supported in part by the National Natural Science Foundation of China under Grant Nos.62372461,62032001 and 62203457in part by the Key Laboratory of Advanced Microprocessor Chips and Systems.
文摘Event-based computation has recently gained increasing research interest for applications of vision recogni-tion due to its intrinsic advantages on efficiency and speed.However,the existing event-based models for vision recogni-tion are faced with several issues,such as large network complexity and expensive training cost.In this paper,we propose an improved multi-liquid state machine(M-LSM)method for high-performance vision recognition.Specifically,we intro-duce two methods,namely multi-state fusion and multi-liquid search,to optimize the liquid state machine(LSM).Multi-state fusion by sampling the liquid state at multiple timesteps could reserve richer spatiotemporal information.We adapt network architecture search(NAS)to find the potential optimal architecture of the multi-liquid state machine.We also train the M-LSM through an unsupervised learning rule spike-timing dependent plasticity(STDP).Our M-LSM is evalu-ated on two event-based datasets and demonstrates state-of-the-art recognition performance with superior advantages on network complexity and training cost.
基金supported by the National Natural Science Foundation of China(Grant No.92248302,51735007)the Beijing Natural Science Foundation(3191001).
文摘Hypertension is a worldwide health problem and a primary risk factor for cardiovascular disease.Continuous monitoring of blood pressure has important clinical value for the early diagnosis and prevention of cardiovascular disease.However,existing technologies for wearable continuous blood pressure monitoring are usually inaccurate,rely on subject-specific calibration and have poor generalization across individuals,which limit their practical applications.Here,we report a new blood pressure measurement method and develop an associated wearable device to implement continuous blood pressure monitoring for new subjects.The wearable device detects cardiac output and pulse waveform features through dual photoplethysmography(PPG)sensors worn on the palmar and dorsal sides of the wrist,incorporating custom-made interface sensors to detect the wearing contact pressure and skin temperature.The detected multichannel signals are fused using a machine-learning algorithm to estimate continuous blood pressure in real time.This dual PPG sensing method effectively eliminates the personal differences in PPG signals caused by different people and different wearing conditions.The proposed wearable device enables continuous blood pressure monitoring with good generalizability across individuals and demonstrates promising potential in personal health care applications.
文摘The authors regret missing out the below change in the acknowledgment section of the article.The original sentence reads as"This work was supported by the Major Research Plan of National Natural Science Foundation of China[No.91649204],the National Key Research and Development Program of China[2016YFC1100100],…"and the same has been corrected to"This work was supported by the National Key Research and Development Program of China[2016YFC1100100],the Major Research Plan of National Natural Science Foundation of China[No.91649204],…"and the same has been corrected to"This work was supported by the National Key Research and Development Program of China[2016YFC1100100],the Major Research Plan of National Natural Science Foundation of China[No.91649204],…".