During the past two centuries, global changes (i.e., enhanced nitrogen deposition) have exerted profound effects on ecological processes of steppe ecosystems. We used litterbag method and mixed litters of three differ...During the past two centuries, global changes (i.e., enhanced nitrogen deposition) have exerted profound effects on ecological processes of steppe ecosystems. We used litterbag method and mixed litters of three different plant species tissues (Stipa baicalensis: Sb, Leymus chinensis: Lc and Artemisia frigid: Af), endemic to Stipa baicalensis Steppe, and measured the mass loss of mixtures over 417 days under the N addition treatment. We studied the effect of N addition (N0: no N addition;N15: 1.5 g N/m<sup>2</sup>·a;N30: 3.0 g N/m<sup>2</sup>·a;N50: 5.0 g N/m<sup>2</sup>·a;N100: 10.0 g N/m<sup>2</sup>·a;N150: 15.0 g N/m<sup>2</sup>·a) on the rate of mixed litter decomposition and nutrient dynamics change. The decomposition constant (k) of leaf mixtures was higher than that of root mixtures. The k values of leaf mixed combinations were 0.880 (Sb + Lc), 1.231 (Lc + Af), 1.027 (Sb + Lc + Af), respectively. The k value of stem was 0.806 (Lc + Af) and the root mixed combinations were 0.665 (Sb + Lc), 0.979 (Lc + Af) and 1.164 (Sb + Lc + Af), respectively. The results indicated that N addition had significantly effect on the mixed litter decomposition and nutrient releasing. The rate of plant tissues litter decomposition had different response to N addition. In the context of N addition, litter decomposition rate and nutrient dynamics were changed by synthetic effect of decaying time, specie types and N addition dose. Our findings suggested that prairie plants may adapt to environmental change by adjusting litter quality, thus retaining the stability of the steppe ecosystem.展开更多
Background:Cartilage repair remains a considerable challenge in regenerative medicine.Despite extensive research on biomaterials for cartilage repair in recent years,issues such as prolonged repair cycles and suboptim...Background:Cartilage repair remains a considerable challenge in regenerative medicine.Despite extensive research on biomaterials for cartilage repair in recent years,issues such as prolonged repair cycles and suboptimal outcomes persist.Organoids,miniature three-dimensional(3D)tissue structures derived from the directed differentiation of stem or progenitor cells,mimic the structure and function of natural organs.Therefore,the construction of cartilage organoids(COs)holds great promise as a novel strategy for cartilage repair.Methods:This study employed a digital light processing system to perform 3D bioprinting of a DNA-silk fibroin(DNA-SF)hydrogel sustained-release system(DSRGT)with bone-marrow mesenchymal stem cells(BMSCs)to construct millimeter-scale CO.COs at different developmental stages were characterized,and the COs with the best cartilage phenotype were selected for in vivo cartilage repair in a rat articular cartilage defect model.Results:This study developed a DSRGT by covalently grafting glucosamine(which promotes cartilage matrix synthesis)and TD-198946(which promotes chondrogenic differentiation)onto a hydrogel using acrylic acid-polyethylene glycolN-hydroxysuccinimide(AC-PEG-NHS).In vitro,4-week COs exhibited higher SRY-box transcription factor 9(SOX9),typeⅡcollagen(ColⅡ),and aggrecan(ACAN)expression and lower typeⅠcollagen(ColⅠ)and typeⅩcollagen(ColⅩ)expression,indicating that 4 weeks is the optimal culture duration for hyaline cartilage development.In vivo,the mitogen-activated protein kinase(MAPK)signaling pathway was upregulated in 4-week COs,enabling cartilage repair within 8 weeks.Transcriptomic analysis revealed that cartilage regenerated with 4-week COs presented gene expression profiles resembling those of healthy cartilage.Conclusion:This study employs DSRGT to construct COs,providing an innovative strategy for the regeneration of cartilage defects.展开更多
With the rapid advancements in biomedical engineering,bioprinting has emerged as a pivotal solution to address the shortage of organ transplants and advance disease model research.The evolution of bioprinting has prog...With the rapid advancements in biomedical engineering,bioprinting has emerged as a pivotal solution to address the shortage of organ transplants and advance disease model research.The evolution of bioprinting has progressed from the fabrication of simple models(1.0)to the fabrication of permanent implants(2.0),tissue engineering scaffolds(3.0),and complex biostructures utilizing living cells(4.0).Nevertheless,significant challenges remain,particularly in accurately replicating the structure and function of host tissues,selecting appropriate materials,and optimizing printing parameters.The integration of artificial intelligence(AI),especially machine learning,provides promising novel opportunities in bioprinting(5.0).This review systematically summarizes the current applications of AI in bioprinting,discussing both construction strategies and application scenarios.It also explores the potential of AI to improve bioprinting in the preparation of complex functional tissues and in situ tissue repair.Overall,the synergy between AI and bioprinting is poised to drive the development of personalized medicine,facilitate high-throughput preparation of in vitro models,and provide robust tools for regenerative medicine and precision healthcare.展开更多
In addition to its recognized role in providing structural support, bone plays a crucial role in maintaining the functionality and balance of various organs by secreting specific cytokines(also known as osteokines). T...In addition to its recognized role in providing structural support, bone plays a crucial role in maintaining the functionality and balance of various organs by secreting specific cytokines(also known as osteokines). This reciprocal influence extends to these organs modulating bone homeostasis and development, although this aspect has yet to be systematically reviewed. This review aims to elucidate this bidirectional crosstalk, with a particular focus on the role of osteokines. Additionally, it presents a unique compilation of evidence highlighting the critical function of extracellular vesicles(EVs) within bone-organ axes for the first time. Moreover, it explores the implications of this crosstalk for designing and implementing bone-on-chips and assembloids, underscoring the importance of comprehending these interactions for advancing physiologically relevant in vitro models. Consequently, this review establishes a robust theoretical foundation for preventing, diagnosing, and treating diseases related to the bone-organ axis from the perspective of cytokines, EVs, hormones, and metabolites.展开更多
Chronic diabetic wounds result from a disrupted microenvironment where oxidative stress,impaired angiogenesis,and persistent infection create a vicious cycle that delays healing.Unfortunately,existing treatments often...Chronic diabetic wounds result from a disrupted microenvironment where oxidative stress,impaired angiogenesis,and persistent infection create a vicious cycle that delays healing.Unfortunately,existing treatments often fail to address these interrelated issues,resulting in suboptimal healing.Here,we propose a base-tip dual-component hydrogel microneedle(MN)system(GBEVs-pVEGF/AgNPs@MNs),consisting of a tip loaded with plant-bacterial hybrid extracellular vesicles(GBEVs-pVEGF)and a base containing silver nanoparticles(AgNPs).Upon penetrating the necrotic tissue of diabetic wounds,our multifunctional MNs could effectively deliver GBEVs-pVEGF,thereby alleviating oxidative stress,promoting cell migration,and facilitating angiogenesis.Additionally,the physical barrier formed by the basal layer synergistically mitigates persistent bacterial infections during wound healing in conjunction with the antimicrobial agent AgNPs.This multifunctional MN system,integrating antioxidant,angiogenic,and antimicrobial properties,effectively restores the disrupted wound microenvironment,offering significant potential for accelerating diabetic wound healing.展开更多
Accumulating research has shed light on the significance of skeletal interoception,in maintaining physiological and metabolic homeostasis related to bone health.This review provides a comprehensive analysis of how ske...Accumulating research has shed light on the significance of skeletal interoception,in maintaining physiological and metabolic homeostasis related to bone health.This review provides a comprehensive analysis of how skeletal interoception influences bone homeostasis,delving into the complex interplay between the nervous system and skeletal system.One key focus of the review is the role of various factors such as prostaglandin E2(PGE2)in skeletal health via skeletal interoception.It explores how nerves innervating the bone tissue communicate with the central nervous system to regulate bone remodeling,a process critical for maintaining bone strength and integrity.Additionally,the review highlights the advancements in biomaterials designed to utilize skeletal interoception for enhancing bone regeneration and treatment of bone disorders.These biomaterials,tailored to interact with the body’s interoceptive pathways,are positioned at the forefront of innovative treatments for conditions like osteoporosis and fractures.They represent a convergence of bioengineering,neuroscience,and orthopedics,aiming to create more efficient and targeted therapies for bone-related disorders.In conclusion,the review underscores the importance of skeletal interoception in physiological regulation and its potential in developing more effective therapies for bone regeneration.It emphasizes the need for further research to fully understand the mechanisms of skeletal interoception and to harness its therapeutic potential fully.展开更多
As the essential technology of human-robotics interactive wearable devices,the robotic knee prosthesis can provide above-knee amputations with functional knee compensations to realize their physical and psychological ...As the essential technology of human-robotics interactive wearable devices,the robotic knee prosthesis can provide above-knee amputations with functional knee compensations to realize their physical and psychological social regression.With the development of mechanical and mechatronic science and technology,the fully active knee prosthesis that can provide subjects with actuating torques has demonstrated a better wearing performance in slope walking and stair ascent when compared with the passive and the semi-active ones.Additionally,with intelligent human-robotics control strategies and algorithms,the wearing effect of the knee prosthesis has been greatly enhanced in terms of stance stability and swing mobility.Therefore,to help readers to obtain an overview of recent progress in robotic knee prosthesis,this paper systematically categorized knee prostheses according to their integrated functions and introduced related research in the past ten years(2010−2020)regarding(1)mechanical design,including uniaxial,four-bar,and multi-bar knee structures,(2)actuating technology,including rigid and elastic actuation,and(3)control method,including mode identification,motion prediction,and automatic control.Quantitative and qualitative analysis and comparison of robotic knee prosthesis-related techniques are conducted.The development trends are concluded as follows:(1)bionic and lightweight structures with better mechanical performance,(2)bionic elastic actuation with energy-saving effect,(3)artificial intelligence-based bionic prosthetic control.Besides,challenges and innovative insights of customized lightweight bionic knee joint structure,highly efficient compact bionic actuation,and personalized daily multi-mode gait adaptation are also discussed in-depth to facilitate the future development of the robotic knee prosthesis.展开更多
Diabetic osteoporosis(DOP)is a significant complication that poses continuous threat to the bone health of patients with diabetes;however,currently,there are no effective treatment strategies.In patients with diabetes...Diabetic osteoporosis(DOP)is a significant complication that poses continuous threat to the bone health of patients with diabetes;however,currently,there are no effective treatment strategies.In patients with diabetes,the increased levels of ferroptosis affect the osteogenic commitment and differentiation of bone mesenchymal stem cells(BMSCs),leading to significant skeletal changes.To address this issue,we aimed to target ferroptosis and propose a novel therapeutic approach for the treatment of DOP.We synthesized ferroptosis-suppressing nanoparticles,which could deliver curcumin,a natural compound,to the bone marrow using tetrahedral framework nucleic acid(tFNA).This delivery system demonstrated excellent curcumin bioavailability and stability,as well as synergistic properties with tFNA.Both in vitro and in vivo experiments revealed that nanoparticles could enhance mitochondrial function by activating the nuclear factor E2-related factor 2(NRF2)/glutathione peroxidase 4(GPX4)pathway,inhibiting ferroptosis,promoting the osteogenic differentiation of BMSCs in the diabetic microenvironment,reducing trabecular loss,and increasing bone formation.These findings suggest that curcumin-containing DNA tetrahedron-based ferroptosissuppressing nanoparticles have a promising potential for the treatment of DOP and other ferroptosis-related diseases.展开更多
Three-dimensional(3D)bioprinting has revolutionized tissue engineering by enabling precise fabrication with bioinks.Among these techniques,digital light processing(DLP)stands out due to its exceptional resolution,spee...Three-dimensional(3D)bioprinting has revolutionized tissue engineering by enabling precise fabrication with bioinks.Among these techniques,digital light processing(DLP)stands out due to its exceptional resolution,speed,and biocompatibility.However,the progress of DLP is hindered by the limited availability of suitable bioinks.Currently,some studies involve simple mixing of different materials,resulting in bioinks that lack uniformity and photopolymerization characteristics.To address this challenge,we present an innovative one-pot synthesis method for bioinks based on methacrylated gelatin/alginate with hydroxyapatite(HAP).This approach offers significant advantages in terms of efficiency and uniformity.The synthesized bioinks demonstrate excellent printability,stability,and notably enhanced mechanical properties,facilitating optimal in vitro compatibility.Additionally,the HAP-hybrid bioinks printed scaffolds demonstrated impressive bone repair capabilities in vivo compared with pure organic bioinks.In conclusion,the Gel/Alg/HAP bioinks presented herein offer an innovative solution for DLP bioprinting within the field of bone tissue engineering.Their multifaceted advantages help overcome the limitations of restricted bioink choices,pushing forward the boundaries of bioprinting technology and contributing to the progress of regenerative medicine and tissue engineering.展开更多
In this paper,to study the mechanical responses of a solid propellant subjected to ultrahigh acceleration overload during the gun-launch process,specifically designed projectile flight tests with an onboard measuremen...In this paper,to study the mechanical responses of a solid propellant subjected to ultrahigh acceleration overload during the gun-launch process,specifically designed projectile flight tests with an onboard measurement system were performed.Two projectiles containing dummy HTPB propellant grains were successfully recovered after the flight tests with an ultrahigh acceleration overload value of 8100 g.The onboard-measured time-resolved axial displacement,contact stress and overload values were successfully obtained and analysed.Uniaxial compression tests of the dummy HTPB propellant used in the gunlaunched tests were carried out at low and intermediate strain rates to characterize the propellant's dynamic properties.A linear viscoelastic constitutive model was employed and applied in finite-element simulations of the projectile-launching process.During the launch process,the dummy propellant grain exhibited large deformation due to the high acceleration overload,possibly leading to friction between the motor case and propellant grain.The calculated contact stress showed good agreement with the experimental results,though discrepancies in the overall displacement of the dummy propellant grain were observed.The dynamic mechanical response process of the dummy propellant grain was analysed in detail.The results can be used to estimate the structural integrity of the analysed dummy propellant grain during the gun-launch process.展开更多
Energy consumption and acoustic noise can be significantly reduced through perching in the sustained flights of small Unmanned Aerial Vehicles(UAVs).However,the existing flying perching robots lack good adaptability o...Energy consumption and acoustic noise can be significantly reduced through perching in the sustained flights of small Unmanned Aerial Vehicles(UAVs).However,the existing flying perching robots lack good adaptability or loading capacity in unstructured environments.Aiming at solving these problems,a deformable UAV perching mechanism with strong adaptability and high loading capacity,which is inspired by the structure and movements of birds'feet,is presented in this paper.Three elastic toes,an inverted crank slider mechanism used to realize the opening and closing movements,and a gear mechanism used to deform between two configurations are included in this mechanism.With experiments on its performance towards different objects,Results show that it can perch on various objects reliably,and its payload is more than 15 times its weight.By integrating it with a quadcopter,it can perch on different types of targets in outdoor environments,such as tree branches,cables,eaves,and spherical lamps.In addition,the energy consumption of the UAV perching system when perching on objects can be reduced to 0.015 times that of hovering.展开更多
The concept and development of bone/cartilage organoids are rapidly gaining momentum,providing opportunities for both fundamental and translational research in bone biology.Bone/cartilage organoids,essentially miniatu...The concept and development of bone/cartilage organoids are rapidly gaining momentum,providing opportunities for both fundamental and translational research in bone biology.Bone/cartilage organoids,essentially miniature bone/cartilage tissues grown in vitro,enable the study of complex cellular interactions,biological processes,and disease pathology in a representative and controlled environment.This review provides a comprehensive and up-to-date overview of the field,focusing on the strategies for bone/cartilage organoid construction strategies,progresses in the research,and potential applications.We delve into the significance of selecting appropriate cells,matrix gels,cytokines/inducers,and construction techniques.Moreover,we explore the role of bone/cartilage organoids in advancing our understanding of bone/cartilage reconstruction,disease modeling,drug screening,disease prevention,and treatment strategies.While acknowledging the potential of these organoids,we discuss the inherent challenges and limitations in the field and propose potential solutions,including the use of bioprinting for organoid induction,AI for improved screening processes,and the exploration of assembloids for more complex,multicellular bone/cartilage organoids models.We believe that with continuous refinement and standardization,bone/cartilage organoids can profoundly impact patient-specific therapeutic interventions and lead the way in regenerative medicine.展开更多
Variable Stiffness Actuation(VSA)is an efficient,safe,and robust actuation technology for bionic robotic joints that have emerged in recent decades.By introducing a variable stiffness elastomer in the actuation system...Variable Stiffness Actuation(VSA)is an efficient,safe,and robust actuation technology for bionic robotic joints that have emerged in recent decades.By introducing a variable stiffness elastomer in the actuation system,the mechanical-electric energy conversion between the motor and the load could be adjusted on-demand,thereby improving the performance of the actuator,such as the peak power reduction,energy saving,bionic actuation,etc.At present,the VSA technology has achieved fruitful research results in designing the actuator mechanism and the stiffness adjustment servo,which has been widely applied in articulated robots,exoskeletons,prostheses,etc.However,how to optimally control the stiffness of VSAs in different application scenarios for better actuator performance is still challenging,where there is still a lack of unified cognition and viewpoints.Therefore,from the perspective of optimal VSA performance,this paper first introduces some typical structural design and servo control techniques of common VSAs and then explains the methods and applications of the Optimal Variable Stiffness Control(OVSC)approaches by theoretically introducing different types of OVSC mathematical models and summarizing OVSC methods with varying optimization goals and application scenarios or cases.In addition,the current research challenges of OVSC methods and possible innovative insights are also presented and discussed in-depth to facilitate the future development of VSA control.展开更多
Bone connection with robot is an important topic in the research of robot assisted fracture reduction surgery.With the method to achieve bone-robot connection in current robots,requirements on reliability and low trau...Bone connection with robot is an important topic in the research of robot assisted fracture reduction surgery.With the method to achieve bone-robot connection in current robots,requirements on reliability and low trauma can not be satisfied at the same time.In this paper,the design,manufacturing,and experiments of a novel Bone Connection Robotic Hand(BCRH)with variable stiffness capability are carried out through the bionics research on human hand and the principle of particle jamming.BCRH’s variable stiffness characteristic is a special connection between“hard connection”and“soft connection”,which is different from the existing researches.It maximizes the reliability of bone-robot connection while minimizes trauma,meets the axial load requirement in clinical practice,and effectively shortens the operating time to less than 40 s(for mode 1)or 2 min(for mode 2).Meanwhile,a theoretical analysis of bone-robot connection failure based on particle jamming is carried out to provide references for the research in this paper and other related studies.展开更多
Triple-negative breast cancer,due to its aggressive nature and lack of targeted treatment,faces serious challenges in breast cancer treatment.Conventional therapies,such as chemotherapy,are encumbered by a range of li...Triple-negative breast cancer,due to its aggressive nature and lack of targeted treatment,faces serious challenges in breast cancer treatment.Conventional therapies,such as chemotherapy,are encumbered by a range of limitations,and there is an urgent need for more effective treatment strategies.Ferroptosis,as an iron-dependent form of cell death,has exhibited promising potential in cancer treatment.Combining ferroptosis with other cancer therapies offers new avenues for treatment.Tetrahedral DNA nanostructure(TDN),a novel DNA-based three-dimensional(3D)nanomaterial,is promising drug delivery vehicle and can be utilized for functionalizing inorganic nanomaterials.In this work,we have demonstrated the preparation of Fe_(3)O_(4)-PEI@TDN-DOX nanocomposites and elucidated their antitumor mechanism.The TDN facilitated the enhanced cellular uptake of polyetherimide(PEI)-modified Fe_(3)O_(4),and the delivery of the chemotherapeutic drug doxorubicin(DOX)further augmented their anti-tumor effect.This novel strategy can destroy the tumor redox homeostasis and produce overwhelming lipid peroxides,consequently sensitizing the tumor to ferroptosis.The integration of ferroptosis with other cancer therapies opens up new possibilities for treatment.This research provides valuable mechanistic insights and practical strategies for leveraging nanotechnology to induce ferroptosis and amplify its impact on tumor cells.展开更多
The spacecraft with multistage solar panels have nonlinear coupling between attitudes of central body and solar panels, especially the rotation of central body is considered in space. The dynamics model is based for d...The spacecraft with multistage solar panels have nonlinear coupling between attitudes of central body and solar panels, especially the rotation of central body is considered in space. The dynamics model is based for dynamics analysis and control, and the multistage solar panels means the dynamics modeling will be very complex. In this research, the Lie group variational integrator method is introduced, and the dynamics model of spacecraft with solar panels that connects together by flexible joints is built. The most obvious character of this method is that the attitudes of central body and solar panels are all described by three-dimensional attitude matrix. The dynamics models of spacecraft with one and three solar panels are established and simulated. The study shows Lie group variational integrator method avoids parameters coupling and effectively reduces difficulty of modeling. The obtained continuous dynamics model based on Lie group is a set of ordinary differential equations and equivalent with traditional dynamics model that offers a basis for the geometry control.展开更多
Perching allows small Unmanned Aerial Vehicles(UAVs)to maintain their altitude while significantly extending their flight duration and reducing noise.However,current research on flying habitats is poorly adapted to un...Perching allows small Unmanned Aerial Vehicles(UAVs)to maintain their altitude while significantly extending their flight duration and reducing noise.However,current research on flying habitats is poorly adapted to unstructured environments,and lacks autonomous capabilities,requiring ideal experimental environments and remote control by personnel.To solve these problems,in this paper,we propose a bat-like UAV perching mechanism by investigating the bat upside-down perching method,which realizes double self-locking in the perching state using the ratchet and four-link dead point mechanisms.Based on this perching mechanism,this study proposes a control strategy for UAVs to track targets and accomplish flight perching autonomously by combining a binocular camera,single-point LiDAR,and pressure sensors.Autonomous perching experiments were conducted for crossbar-type objects outdoors.The experimental results show that a multirotor UAV equipped with the perching mechanism and sensors can reliably achieve autonomous flight perching and re-flying off the target outdoors.The power consumption is reduced to 2.9%of the hovering state when perched on the target object.展开更多
文摘During the past two centuries, global changes (i.e., enhanced nitrogen deposition) have exerted profound effects on ecological processes of steppe ecosystems. We used litterbag method and mixed litters of three different plant species tissues (Stipa baicalensis: Sb, Leymus chinensis: Lc and Artemisia frigid: Af), endemic to Stipa baicalensis Steppe, and measured the mass loss of mixtures over 417 days under the N addition treatment. We studied the effect of N addition (N0: no N addition;N15: 1.5 g N/m<sup>2</sup>·a;N30: 3.0 g N/m<sup>2</sup>·a;N50: 5.0 g N/m<sup>2</sup>·a;N100: 10.0 g N/m<sup>2</sup>·a;N150: 15.0 g N/m<sup>2</sup>·a) on the rate of mixed litter decomposition and nutrient dynamics change. The decomposition constant (k) of leaf mixtures was higher than that of root mixtures. The k values of leaf mixed combinations were 0.880 (Sb + Lc), 1.231 (Lc + Af), 1.027 (Sb + Lc + Af), respectively. The k value of stem was 0.806 (Lc + Af) and the root mixed combinations were 0.665 (Sb + Lc), 0.979 (Lc + Af) and 1.164 (Sb + Lc + Af), respectively. The results indicated that N addition had significantly effect on the mixed litter decomposition and nutrient releasing. The rate of plant tissues litter decomposition had different response to N addition. In the context of N addition, litter decomposition rate and nutrient dynamics were changed by synthetic effect of decaying time, specie types and N addition dose. Our findings suggested that prairie plants may adapt to environmental change by adjusting litter quality, thus retaining the stability of the steppe ecosystem.
基金supported by the National Key Research and Development Program of China(2022YFB3804300)the National Natural Science Foundation of China(82230071,32471395,82427809,82472479)+2 种基金the Shanghai Science and Technology Innovation Action Plan(23141900600)the Research Physician Training Program of Shanghai Hospital Development Center(SHDC2023CRT013)the Shanghai Municipal Demonstration Project for Innovative Medical Device Applications(23SHS05700)。
文摘Background:Cartilage repair remains a considerable challenge in regenerative medicine.Despite extensive research on biomaterials for cartilage repair in recent years,issues such as prolonged repair cycles and suboptimal outcomes persist.Organoids,miniature three-dimensional(3D)tissue structures derived from the directed differentiation of stem or progenitor cells,mimic the structure and function of natural organs.Therefore,the construction of cartilage organoids(COs)holds great promise as a novel strategy for cartilage repair.Methods:This study employed a digital light processing system to perform 3D bioprinting of a DNA-silk fibroin(DNA-SF)hydrogel sustained-release system(DSRGT)with bone-marrow mesenchymal stem cells(BMSCs)to construct millimeter-scale CO.COs at different developmental stages were characterized,and the COs with the best cartilage phenotype were selected for in vivo cartilage repair in a rat articular cartilage defect model.Results:This study developed a DSRGT by covalently grafting glucosamine(which promotes cartilage matrix synthesis)and TD-198946(which promotes chondrogenic differentiation)onto a hydrogel using acrylic acid-polyethylene glycolN-hydroxysuccinimide(AC-PEG-NHS).In vitro,4-week COs exhibited higher SRY-box transcription factor 9(SOX9),typeⅡcollagen(ColⅡ),and aggrecan(ACAN)expression and lower typeⅠcollagen(ColⅠ)and typeⅩcollagen(ColⅩ)expression,indicating that 4 weeks is the optimal culture duration for hyaline cartilage development.In vivo,the mitogen-activated protein kinase(MAPK)signaling pathway was upregulated in 4-week COs,enabling cartilage repair within 8 weeks.Transcriptomic analysis revealed that cartilage regenerated with 4-week COs presented gene expression profiles resembling those of healthy cartilage.Conclusion:This study employs DSRGT to construct COs,providing an innovative strategy for the regeneration of cartilage defects.
基金financially supported by the National Natural Science Foundation of China(Nos.32471396,82230071,82172098,82201716,and 61973206)the National Key R&D Program of China(No.2023YFC2411303)+4 种基金the Integrated Project of Major Research Plan of the National Natural Science Foundation of China(No.92249303)the Shanghai Committee of Science and Technology(No.23141900600,Laboratory Animal Research Project)the Shanghai Clinical Research Plan of SHDC2023CRT01the Young Elite Scientist Sponsorship Program by the China Association for Science and Technology(No.YESS20230049)the Baoshan District Health Commission Talents(Excellent Academic Leaders)Program(No.BSWSYX-2024-05)。
文摘With the rapid advancements in biomedical engineering,bioprinting has emerged as a pivotal solution to address the shortage of organ transplants and advance disease model research.The evolution of bioprinting has progressed from the fabrication of simple models(1.0)to the fabrication of permanent implants(2.0),tissue engineering scaffolds(3.0),and complex biostructures utilizing living cells(4.0).Nevertheless,significant challenges remain,particularly in accurately replicating the structure and function of host tissues,selecting appropriate materials,and optimizing printing parameters.The integration of artificial intelligence(AI),especially machine learning,provides promising novel opportunities in bioprinting(5.0).This review systematically summarizes the current applications of AI in bioprinting,discussing both construction strategies and application scenarios.It also explores the potential of AI to improve bioprinting in the preparation of complex functional tissues and in situ tissue repair.Overall,the synergy between AI and bioprinting is poised to drive the development of personalized medicine,facilitate high-throughput preparation of in vitro models,and provide robust tools for regenerative medicine and precision healthcare.
基金supported by the National Natural Science Foundation of China (82230071, 82172098)the Integrated Project of Major Research Plan of National Natural Science Foundation of China (92249303)+2 种基金the Laboratory Animal Research Project of Shanghai Committee of Science and Technology (23141900600)the Shanghai Clinical Research Plan (SHDC2023CRT01)the Young Elite Scientist Sponsorship Program by China Association for Science and Technology (YESS20230049)。
文摘In addition to its recognized role in providing structural support, bone plays a crucial role in maintaining the functionality and balance of various organs by secreting specific cytokines(also known as osteokines). This reciprocal influence extends to these organs modulating bone homeostasis and development, although this aspect has yet to be systematically reviewed. This review aims to elucidate this bidirectional crosstalk, with a particular focus on the role of osteokines. Additionally, it presents a unique compilation of evidence highlighting the critical function of extracellular vesicles(EVs) within bone-organ axes for the first time. Moreover, it explores the implications of this crosstalk for designing and implementing bone-on-chips and assembloids, underscoring the importance of comprehending these interactions for advancing physiologically relevant in vitro models. Consequently, this review establishes a robust theoretical foundation for preventing, diagnosing, and treating diseases related to the bone-organ axis from the perspective of cytokines, EVs, hormones, and metabolites.
基金support from the National Natural Science Foundation of China(No.82472444).
文摘Chronic diabetic wounds result from a disrupted microenvironment where oxidative stress,impaired angiogenesis,and persistent infection create a vicious cycle that delays healing.Unfortunately,existing treatments often fail to address these interrelated issues,resulting in suboptimal healing.Here,we propose a base-tip dual-component hydrogel microneedle(MN)system(GBEVs-pVEGF/AgNPs@MNs),consisting of a tip loaded with plant-bacterial hybrid extracellular vesicles(GBEVs-pVEGF)and a base containing silver nanoparticles(AgNPs).Upon penetrating the necrotic tissue of diabetic wounds,our multifunctional MNs could effectively deliver GBEVs-pVEGF,thereby alleviating oxidative stress,promoting cell migration,and facilitating angiogenesis.Additionally,the physical barrier formed by the basal layer synergistically mitigates persistent bacterial infections during wound healing in conjunction with the antimicrobial agent AgNPs.This multifunctional MN system,integrating antioxidant,angiogenic,and antimicrobial properties,effectively restores the disrupted wound microenvironment,offering significant potential for accelerating diabetic wound healing.
基金National Natural Science Foundation of China(82230071,82172098)Integrated Project of Major Research Plan of National Natural Science Foundation of China(92249303)+2 种基金Shanghai Committee of Science and Technology(23141900600,Laboratory Animal Research Project)Shanghai Clinical Research Plan of SHDC2023CRT01Young Elite Scientist Sponsorship Program by China Association for Science and Technology(YESS20230049)。
文摘Accumulating research has shed light on the significance of skeletal interoception,in maintaining physiological and metabolic homeostasis related to bone health.This review provides a comprehensive analysis of how skeletal interoception influences bone homeostasis,delving into the complex interplay between the nervous system and skeletal system.One key focus of the review is the role of various factors such as prostaglandin E2(PGE2)in skeletal health via skeletal interoception.It explores how nerves innervating the bone tissue communicate with the central nervous system to regulate bone remodeling,a process critical for maintaining bone strength and integrity.Additionally,the review highlights the advancements in biomaterials designed to utilize skeletal interoception for enhancing bone regeneration and treatment of bone disorders.These biomaterials,tailored to interact with the body’s interoceptive pathways,are positioned at the forefront of innovative treatments for conditions like osteoporosis and fractures.They represent a convergence of bioengineering,neuroscience,and orthopedics,aiming to create more efficient and targeted therapies for bone-related disorders.In conclusion,the review underscores the importance of skeletal interoception in physiological regulation and its potential in developing more effective therapies for bone regeneration.It emphasizes the need for further research to fully understand the mechanisms of skeletal interoception and to harness its therapeutic potential fully.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.62003060,51975070 and 62033001)the National Key Research and Development Program of China under Grant 2020YFB1313000.
文摘As the essential technology of human-robotics interactive wearable devices,the robotic knee prosthesis can provide above-knee amputations with functional knee compensations to realize their physical and psychological social regression.With the development of mechanical and mechatronic science and technology,the fully active knee prosthesis that can provide subjects with actuating torques has demonstrated a better wearing performance in slope walking and stair ascent when compared with the passive and the semi-active ones.Additionally,with intelligent human-robotics control strategies and algorithms,the wearing effect of the knee prosthesis has been greatly enhanced in terms of stance stability and swing mobility.Therefore,to help readers to obtain an overview of recent progress in robotic knee prosthesis,this paper systematically categorized knee prostheses according to their integrated functions and introduced related research in the past ten years(2010−2020)regarding(1)mechanical design,including uniaxial,four-bar,and multi-bar knee structures,(2)actuating technology,including rigid and elastic actuation,and(3)control method,including mode identification,motion prediction,and automatic control.Quantitative and qualitative analysis and comparison of robotic knee prosthesis-related techniques are conducted.The development trends are concluded as follows:(1)bionic and lightweight structures with better mechanical performance,(2)bionic elastic actuation with energy-saving effect,(3)artificial intelligence-based bionic prosthetic control.Besides,challenges and innovative insights of customized lightweight bionic knee joint structure,highly efficient compact bionic actuation,and personalized daily multi-mode gait adaptation are also discussed in-depth to facilitate the future development of the robotic knee prosthesis.
基金This research was financially supported by the National Key R&D Program of China(2019YFA0110600)the National Natural Science Foundation of China(82370932,81970917,82370929,81970916,81800947,82101077)+2 种基金the Research and Develop Program,West China Hospital of Stomatology Sichuan University(RD-03-202102,RD03202302)Sichuan Science and Technology Program(2022NSFSC0002)Sichuan Province Youth Science and Technology Innovation Team(2022JDTD0021).
文摘Diabetic osteoporosis(DOP)is a significant complication that poses continuous threat to the bone health of patients with diabetes;however,currently,there are no effective treatment strategies.In patients with diabetes,the increased levels of ferroptosis affect the osteogenic commitment and differentiation of bone mesenchymal stem cells(BMSCs),leading to significant skeletal changes.To address this issue,we aimed to target ferroptosis and propose a novel therapeutic approach for the treatment of DOP.We synthesized ferroptosis-suppressing nanoparticles,which could deliver curcumin,a natural compound,to the bone marrow using tetrahedral framework nucleic acid(tFNA).This delivery system demonstrated excellent curcumin bioavailability and stability,as well as synergistic properties with tFNA.Both in vitro and in vivo experiments revealed that nanoparticles could enhance mitochondrial function by activating the nuclear factor E2-related factor 2(NRF2)/glutathione peroxidase 4(GPX4)pathway,inhibiting ferroptosis,promoting the osteogenic differentiation of BMSCs in the diabetic microenvironment,reducing trabecular loss,and increasing bone formation.These findings suggest that curcumin-containing DNA tetrahedron-based ferroptosissuppressing nanoparticles have a promising potential for the treatment of DOP and other ferroptosis-related diseases.
基金financial support from the National Natural Science Foundation of China(Nos.82202335,82230071,and 82172098)the Shanghai Sailing Program(No.22YF1414000).
文摘Three-dimensional(3D)bioprinting has revolutionized tissue engineering by enabling precise fabrication with bioinks.Among these techniques,digital light processing(DLP)stands out due to its exceptional resolution,speed,and biocompatibility.However,the progress of DLP is hindered by the limited availability of suitable bioinks.Currently,some studies involve simple mixing of different materials,resulting in bioinks that lack uniformity and photopolymerization characteristics.To address this challenge,we present an innovative one-pot synthesis method for bioinks based on methacrylated gelatin/alginate with hydroxyapatite(HAP).This approach offers significant advantages in terms of efficiency and uniformity.The synthesized bioinks demonstrate excellent printability,stability,and notably enhanced mechanical properties,facilitating optimal in vitro compatibility.Additionally,the HAP-hybrid bioinks printed scaffolds demonstrated impressive bone repair capabilities in vivo compared with pure organic bioinks.In conclusion,the Gel/Alg/HAP bioinks presented herein offer an innovative solution for DLP bioprinting within the field of bone tissue engineering.Their multifaceted advantages help overcome the limitations of restricted bioink choices,pushing forward the boundaries of bioprinting technology and contributing to the progress of regenerative medicine and tissue engineering.
文摘In this paper,to study the mechanical responses of a solid propellant subjected to ultrahigh acceleration overload during the gun-launch process,specifically designed projectile flight tests with an onboard measurement system were performed.Two projectiles containing dummy HTPB propellant grains were successfully recovered after the flight tests with an ultrahigh acceleration overload value of 8100 g.The onboard-measured time-resolved axial displacement,contact stress and overload values were successfully obtained and analysed.Uniaxial compression tests of the dummy HTPB propellant used in the gunlaunched tests were carried out at low and intermediate strain rates to characterize the propellant's dynamic properties.A linear viscoelastic constitutive model was employed and applied in finite-element simulations of the projectile-launching process.During the launch process,the dummy propellant grain exhibited large deformation due to the high acceleration overload,possibly leading to friction between the motor case and propellant grain.The calculated contact stress showed good agreement with the experimental results,though discrepancies in the overall displacement of the dummy propellant grain were observed.The dynamic mechanical response process of the dummy propellant grain was analysed in detail.The results can be used to estimate the structural integrity of the analysed dummy propellant grain during the gun-launch process.
基金supported by the National Key R&D Program of China[Grant No.2020YFB1313000]National Natural Science Foundation of China[Grant No.51975070,62003060,62073211].
文摘Energy consumption and acoustic noise can be significantly reduced through perching in the sustained flights of small Unmanned Aerial Vehicles(UAVs).However,the existing flying perching robots lack good adaptability or loading capacity in unstructured environments.Aiming at solving these problems,a deformable UAV perching mechanism with strong adaptability and high loading capacity,which is inspired by the structure and movements of birds'feet,is presented in this paper.Three elastic toes,an inverted crank slider mechanism used to realize the opening and closing movements,and a gear mechanism used to deform between two configurations are included in this mechanism.With experiments on its performance towards different objects,Results show that it can perch on various objects reliably,and its payload is more than 15 times its weight.By integrating it with a quadcopter,it can perch on different types of targets in outdoor environments,such as tree branches,cables,eaves,and spherical lamps.In addition,the energy consumption of the UAV perching system when perching on objects can be reduced to 0.015 times that of hovering.
基金financially supported by National Natural Science Foundation of China (32471396,82230071,82172098,82201716)Integrated Project of Major Research Plan of National Natural Science Foundation of China (92249303)+2 种基金Shanghai Committee of Science and Technology (23141900600,Laboratory Animal Research Project)Shanghai Clinical Research Plan of SHDC2023CRT01Young Elite Scientist Sponsorship Program by China Association for Science and Technology (YESS20230049)。
文摘The concept and development of bone/cartilage organoids are rapidly gaining momentum,providing opportunities for both fundamental and translational research in bone biology.Bone/cartilage organoids,essentially miniature bone/cartilage tissues grown in vitro,enable the study of complex cellular interactions,biological processes,and disease pathology in a representative and controlled environment.This review provides a comprehensive and up-to-date overview of the field,focusing on the strategies for bone/cartilage organoid construction strategies,progresses in the research,and potential applications.We delve into the significance of selecting appropriate cells,matrix gels,cytokines/inducers,and construction techniques.Moreover,we explore the role of bone/cartilage organoids in advancing our understanding of bone/cartilage reconstruction,disease modeling,drug screening,disease prevention,and treatment strategies.While acknowledging the potential of these organoids,we discuss the inherent challenges and limitations in the field and propose potential solutions,including the use of bioprinting for organoid induction,AI for improved screening processes,and the exploration of assembloids for more complex,multicellular bone/cartilage organoids models.We believe that with continuous refinement and standardization,bone/cartilage organoids can profoundly impact patient-specific therapeutic interventions and lead the way in regenerative medicine.
基金National Key Research and Development Program of China[Grant No.2020YFB1313000]National Natural Science Foundation of China[Grant No.62003060,62101086,51975070]+2 种基金China Postdoctoral Science Foundation[2021M693769]Natural Science Foundation of Chongqing,China[Grant No.cstc2021jcyj-bsh0180]Scientific and Technological Research Program of Chongqing Municipal Education Commission[Grant No.KJQN202100648].
文摘Variable Stiffness Actuation(VSA)is an efficient,safe,and robust actuation technology for bionic robotic joints that have emerged in recent decades.By introducing a variable stiffness elastomer in the actuation system,the mechanical-electric energy conversion between the motor and the load could be adjusted on-demand,thereby improving the performance of the actuator,such as the peak power reduction,energy saving,bionic actuation,etc.At present,the VSA technology has achieved fruitful research results in designing the actuator mechanism and the stiffness adjustment servo,which has been widely applied in articulated robots,exoskeletons,prostheses,etc.However,how to optimally control the stiffness of VSAs in different application scenarios for better actuator performance is still challenging,where there is still a lack of unified cognition and viewpoints.Therefore,from the perspective of optimal VSA performance,this paper first introduces some typical structural design and servo control techniques of common VSAs and then explains the methods and applications of the Optimal Variable Stiffness Control(OVSC)approaches by theoretically introducing different types of OVSC mathematical models and summarizing OVSC methods with varying optimization goals and application scenarios or cases.In addition,the current research challenges of OVSC methods and possible innovative insights are also presented and discussed in-depth to facilitate the future development of VSA control.
基金This research was supported by the National Natural Science Foundation of China(Grant Nos.51975070,62003060 and 52075051)the National Key Research and Development Program of China(Grant No.2020YFB1313000).
文摘Bone connection with robot is an important topic in the research of robot assisted fracture reduction surgery.With the method to achieve bone-robot connection in current robots,requirements on reliability and low trauma can not be satisfied at the same time.In this paper,the design,manufacturing,and experiments of a novel Bone Connection Robotic Hand(BCRH)with variable stiffness capability are carried out through the bionics research on human hand and the principle of particle jamming.BCRH’s variable stiffness characteristic is a special connection between“hard connection”and“soft connection”,which is different from the existing researches.It maximizes the reliability of bone-robot connection while minimizes trauma,meets the axial load requirement in clinical practice,and effectively shortens the operating time to less than 40 s(for mode 1)or 2 min(for mode 2).Meanwhile,a theoretical analysis of bone-robot connection failure based on particle jamming is carried out to provide references for the research in this paper and other related studies.
基金supported by the National Key R&D Program of China(No.2019YFA0110600)the National Natural Science Foundation of China(Nos.82370929 and 81970916)+3 种基金the Sichuan Science and Technology Program(Nos.2022NSFSC0002 and 2023YFG022)Sichuan Province Youth Science and Technology Innovation Team(No.2022JDTD0021)Research and Develop Program,West China Hospital of Stomatology Sichuan University(No.RD03202302)the Research Funding from West China School/Hospital of Stomatology Sichuan University(No.QDJF2022-2)。
文摘Triple-negative breast cancer,due to its aggressive nature and lack of targeted treatment,faces serious challenges in breast cancer treatment.Conventional therapies,such as chemotherapy,are encumbered by a range of limitations,and there is an urgent need for more effective treatment strategies.Ferroptosis,as an iron-dependent form of cell death,has exhibited promising potential in cancer treatment.Combining ferroptosis with other cancer therapies offers new avenues for treatment.Tetrahedral DNA nanostructure(TDN),a novel DNA-based three-dimensional(3D)nanomaterial,is promising drug delivery vehicle and can be utilized for functionalizing inorganic nanomaterials.In this work,we have demonstrated the preparation of Fe_(3)O_(4)-PEI@TDN-DOX nanocomposites and elucidated their antitumor mechanism.The TDN facilitated the enhanced cellular uptake of polyetherimide(PEI)-modified Fe_(3)O_(4),and the delivery of the chemotherapeutic drug doxorubicin(DOX)further augmented their anti-tumor effect.This novel strategy can destroy the tumor redox homeostasis and produce overwhelming lipid peroxides,consequently sensitizing the tumor to ferroptosis.The integration of ferroptosis with other cancer therapies opens up new possibilities for treatment.This research provides valuable mechanistic insights and practical strategies for leveraging nanotechnology to induce ferroptosis and amplify its impact on tumor cells.
基金the financial support from the National Natural Science Foundation of China (Grants 11732005 and 11472058)
文摘The spacecraft with multistage solar panels have nonlinear coupling between attitudes of central body and solar panels, especially the rotation of central body is considered in space. The dynamics model is based for dynamics analysis and control, and the multistage solar panels means the dynamics modeling will be very complex. In this research, the Lie group variational integrator method is introduced, and the dynamics model of spacecraft with solar panels that connects together by flexible joints is built. The most obvious character of this method is that the attitudes of central body and solar panels are all described by three-dimensional attitude matrix. The dynamics models of spacecraft with one and three solar panels are established and simulated. The study shows Lie group variational integrator method avoids parameters coupling and effectively reduces difficulty of modeling. The obtained continuous dynamics model based on Lie group is a set of ordinary differential equations and equivalent with traditional dynamics model that offers a basis for the geometry control.
基金financially supported by National Key Research&Development Program of China[Grant No.2020YFB1313000]National Natural Science Foundation of China[Grant No.62003060]+1 种基金China Postdoctoral Science Foundation[2022M720566]Natural Science Foundation of Chongqing,China[CSTB2022NSCQ-MSX1297].
文摘Perching allows small Unmanned Aerial Vehicles(UAVs)to maintain their altitude while significantly extending their flight duration and reducing noise.However,current research on flying habitats is poorly adapted to unstructured environments,and lacks autonomous capabilities,requiring ideal experimental environments and remote control by personnel.To solve these problems,in this paper,we propose a bat-like UAV perching mechanism by investigating the bat upside-down perching method,which realizes double self-locking in the perching state using the ratchet and four-link dead point mechanisms.Based on this perching mechanism,this study proposes a control strategy for UAVs to track targets and accomplish flight perching autonomously by combining a binocular camera,single-point LiDAR,and pressure sensors.Autonomous perching experiments were conducted for crossbar-type objects outdoors.The experimental results show that a multirotor UAV equipped with the perching mechanism and sensors can reliably achieve autonomous flight perching and re-flying off the target outdoors.The power consumption is reduced to 2.9%of the hovering state when perched on the target object.
