In recent years,various transformable nanoparticles（NPs）were successfully prepared and widely utilized for biomedical applications.The sizes,surface charges or morphologies of transformable NPs would affect their be...In recent years,various transformable nanoparticles（NPs）were successfully prepared and widely utilized for biomedical applications.The sizes,surface charges or morphologies of transformable NPs would affect their behavior in physiological/pathological conditions including circulation,penetration,accumulation and retention etc.The other way round,the NPs could be precisely modulated in the specific physiological/pathological condition for precision theranostics of diseases.Herein,we summarized recent advances of transformable NPs for disease diagnostics and therapy.In this review,the transformation of NPs was divided into three groups including changes in size,surface charge and morphology,which was induced by internal stimuli,such as p H,enzyme,receptor or external stimuli,such as light,temperature etc.Moreover,we focused on the characterization of structural transformation in vivo,as well as the transformation-induced biological effects for theranostics of disease.展开更多
Induction of tumor cell senescence has become a promising strategy for anti-tumor immunotherapy,but fibrotic matrix severely blocks senescence inducers penetration and immune cells infiltration.Herein,we designed a ca...Induction of tumor cell senescence has become a promising strategy for anti-tumor immunotherapy,but fibrotic matrix severely blocks senescence inducers penetration and immune cells infiltration.Herein,we designed a cancer-associated fibroblasts(CAFs)triggered structure-transformable nano-assembly(HSD-P@V),which can directionally deliver valsartan(Val,CAFs regulator)and doxorubicin(DOX,senescence inducer)to the specific targets.In detail,DOX is conjugated with hyaluronic acid(HA)via diselenide bonds(Se-Se)to form HSD micelles,while CAFs-sensitive peptide is grafted onto the HSD to form a hydrophilic polymer,which is coated on Val nanocrystals(VNs)surface for improving the stability and achieving responsive release.Once arriving at tumor microenvironment and touching CAFs,HSD-P@V disintegrates into VNs and HSD micelles due to sensitive peptide detachment.VNs can degrade the extracellularmatrix,leading to the enhanced penetration of HSD.HSD targets tumor cells,releases DOX to induce senescence,and recruits effector immune cells.Furthermore,senescent cells are cleared by the recruited immune cells to finish the integrated anti-tumor therapy.In vitro and in vivo results show that the nanoassembly remarkably inhibits tumor growth as well as lungmetastasis,and extends tumorbearing mice survival.This work provides a promising paradigm of programmed delivering multi-site nanomedicine for cancer immunotherapy.展开更多
The contemplation of contemporary architectural designs shows an increasing demand for the development of more adaptable, flexible and transformable structures. This type of structures can adapt with different environ...The contemplation of contemporary architectural designs shows an increasing demand for the development of more adaptable, flexible and transformable structures. This type of structures can adapt with different environmental conditions and meet different functions. This can help in reducing environmental waste and pollution associated with many buildings and above all can save on cost and time. Natural systems have inspired human being, since they began to build and design. Architects and designers have utilized nature as one of the main resources of information for the creation of innovative architectural spaces. One of the unique features of natural structures is the way that their components open and close in order to respond to a particular requirement or the environmental changes. This aspect has inspired many designers for the development of transformable architectural structures that can change their shape and geometry to be able to adapt with specific conditions. To make a way toward the design of transformable structure for temporary applications, the authors have developed a new type of adaptable structures according to natural forms. The proposed design applies the transformation principles that exist in potato＇s flower and the movement mechanisms used in a spider＇s leg. The design is able to fit to different topographies and have a potential to be folded to a very compact state in a very short period of time. The detailed design and the different configurations of the system applications will be presented in this paper. The result of the study shows that using modular triangular plates can create a changeable module that is not only able to respond to different functions and environmental changes but it is also able to shape different configuration to be able to respond to different user＇s ambitions. The compactability of this structure into 1/3 of its base dimensions; makes its transportation fast and with minimum costs. These capabilities make this structure suitable for temporary buildings such as exhibitions, temporary settlements or hospital in damaged areas.展开更多
Transformable architecture is totally linked to the study and knowledge of geometry.There are some materials in nature,whose geometric invariants establish equivalent structural behavior regarding the scalar transform...Transformable architecture is totally linked to the study and knowledge of geometry.There are some materials in nature,whose geometric invariants establish equivalent structural behavior regarding the scalar transformations,developing different spatial typologies according to dimensional variation.Auxetic materials are characterized by their negative Poisson’s ratio.They can change their geometric configuration from a line to a surface,and from a surface to a volume or spatial framework.This paper is based on establishing and comparing those stellated reentrant auxetic geometries to be able to build new spaces defined by their capacity for architectural transformation,studying analytically geometric properties of stellated reentrant auxetic structures that,from the molecular to the macroscopic level,can be part of the architecture construction.In this investigation,a comparative study by means of CAD of stellated reentrant auxetic patterns has been realized.A Computer-Aided Design study of stellated reentrant auxetic structures will be realized to use them in architecture.The geometric behavior of the different stellated reentrant auxetic patterns is analyzed from the developed study to generate a systematic comparison,evaluating properties of these forms,such as their maximum achievable area reductions in relation to the total length of bars of the structure,in order to obtain a growth factor.展开更多
The structural change-mediated catalytic activity regulation plays a significant role in the biological functions of natural enzymes.However,there is virtually no artificial nanozyme reported that can achieve natural ...The structural change-mediated catalytic activity regulation plays a significant role in the biological functions of natural enzymes.However,there is virtually no artificial nanozyme reported that can achieve natural enzyme-like stringent spatiotemporal structure-based catalytic activity regulation.Here,we report a subnanostructural transformable gold@ceria(STGC-PEG)nanozyme that performs tunable catalytic activities via near-infrared(NIR)light-mediated sub-nanostructural transformation.The gold core in STGC-PEG can generate energetic hot electrons upon NIR irradiation,wherein an internal sub-nanostructural transformation is initiated by the conversion between CeO;and electron-rich state of CeO;-x,and active oxygen vacancies generation via the hot-electron injection.Interestingly,the sub-nanostructural transformation of STGC-PEG enhances peroxidase-like activity and unprecedentedly activates plasmon-promoted oxidase-like activity,allowing highly efficient low-power NIR light(50 m W cm;)-activated photocatalytic therapy of tumors.Our atomic-level design and fabrication provide a platform to precisely regulate the catalytic activities of nanozymes via a light-mediated sub-nanostructural transformation,approaching natural enzyme-like activity control in complex living systems.展开更多
Developing bulk metallic glass composites(BMGCs)with high toughness is vital for their practical application.However,the influence of different microstructures on the impact toughness of BMGCs is still unclear.The eff...Developing bulk metallic glass composites(BMGCs)with high toughness is vital for their practical application.However,the influence of different microstructures on the impact toughness of BMGCs is still unclear.The effects of Al addition and cryogenic cyclic treatment(CCT)on the Charpy impact toughness,a K,at 298 and 77 K of a series of phase-transformable BMGCs are investigated in this work.It is found that deformation-induced martensitic transformation(DIMT)of theβ-Ti dendrites is the dominant toughening mechanism in the phase-transformable BMGCs at 298 K,but at 77 K,the toughness of BMGCs is primarily determined by the intrinsic toughness of the glass matrix.The addition of Al can moderately tune theβ-Ti phase stability,which then affects the amount of DIMT and impact toughness of the BMGCs at 298 K.However,at 77 K,Al addition causes a monotonic decrease in the toughness of the BMGCs due to the embrittlement of the glass matrix.It is found that CCT can effectively rejuvenate the phase-transformable BMGCs,which results in an enhanced impact toughness at 298 K.However,the toughness at 77 K monotonously decreases with increasing the number of CCT cycles,suggesting that the rejuvenation of the glass matrix affects the toughness at both 298 and 77 K of BMGCs,but in dramatically different ways.These findings reveal the influence of microstructures and CCT on the impact toughness of BMGCs and provide insights that could be useful for designing tougher BMGs and BMGCs.展开更多
The introduction of alleles into commercial crop breeding pipelines is both time consuming and costly.Two technologies that are disrupting traditional breeding processes are doubled haploid(DH)breeding and genome edit...The introduction of alleles into commercial crop breeding pipelines is both time consuming and costly.Two technologies that are disrupting traditional breeding processes are doubled haploid(DH)breeding and genome editing(GE).Recently,these techniques were combined into a GE trait delivery system called HI-Edit(Haploid Inducer-Edit).In HI-Edit,the pollen of a haploid inducer line is reprogrammed to deliver GE traits to any variety,obviating recurrent selection.For HI-Edit to operate at scale,an efficient transformable HI line is needed,but most maize varieties are recalcitrant to transformation,and haploid inducers are especially difficult to transform given their aberrant reproductive behaviors.Leveraging marker assisted selection and a three-tiered testing scheme,we report the development of new Iodent and Stiff Stalk maize germplasm that are transformable,have high haploid induction rates,and exhibit a robust,genetically-dominant anthocyanin native trait that may be used for rapid haploid identification.We show that transformation of these elite‘‘HI-Edit”lines is enhanced using the BABYBOOM and WUSCHEL morphogenetic factors.Finally,we evaluate the HI-Edit performance of one of the lines against both Stiff Stalk and non-Stiff Stalk testers.The strategy and results of this study should facilitate the development of commercially scalable HI-Edit systems in diverse crops.展开更多
To maneuver in unstructured terrains where the ground might be soft, hard, flat or rough, a transformable wheel-track robot (NEZA-I) with a self-adaptive mobile mechanism is proposed and developed. The robot consists ...To maneuver in unstructured terrains where the ground might be soft, hard, flat or rough, a transformable wheel-track robot (NEZA-I) with a self-adaptive mobile mechanism is proposed and developed. The robot consists of a control system unit, two symmetric transformable wheel-track (TWT) units, and a rear-wheel unit. The TWT unit is the main mobile mechanism for the NEZA-I robot, with the rear-wheel unit acting as an assistant mechanism. Driven only by one servomotor, each TWT unit can efficiently select between track mode and wheel mode for optimal locomotion, autonomously switching locomotion mode and track configuration with changes in the terrain. In this paper, the mechanism structure, the self-adaptive drive system, the locomotion mode and posture of the NEZA-I robot are presented, the kinematic relation of the inside parts of the TWT unit is analysed, and the mathematic model of the constraint relation between the mobile mechanism and the ground, abbreviated to "MGCR model" is set up for the NEZA-I robot to go through some typical unstructured environments. The mechanism parameters, which influence the self-adaptability of the NEZA-I robot, are found and optimized. Basic experiments show that the mobile mechanism has the self-adaptability to navigate in unstructured terrains and has superior obstacle-negotiating performance, and that the MGCR model and the analysis method of mechanism parameters are reasonable. From a mechanism point of view, it can provide an idea for research on the adaptive control of the robot.展开更多
Mild photothermal therapy combined with immune checkpoint blockade has received increasing attention for the treatment of advanced or metastatic cancers due to its good therapeutic efficacy.However,it remains a challe...Mild photothermal therapy combined with immune checkpoint blockade has received increasing attention for the treatment of advanced or metastatic cancers due to its good therapeutic efficacy.However,it remains a challenge to facilely integrate the two therapies and make it potential for clinical translation.This work designed a peptide-photosensitizer conjugate(PPC),which consisted of a PD-L1 antagonist peptide(CVRARTR),an MMP-2 specific cleavable sequence,a self-assembling motif,and the photosensitizer Purpurin 18.The single-component PPC can self-assemble into nanospheres which is suitable for intravenous injection.The PPC nanosphere is cleaved by MMP-2 when it accumulates in tumor sites,thereby initiating the cancer-specific release of the antagonist peptide.Simultaneously,the nanospheres gradually transform into co-assembled nanofibers,which promotes the retention of the remaining parts within the tumor.In vivo studies demonstrated that PPC nanospheres under laser irradiation promote the infiltration of cytotoxic T lymphocytes and maturation of DCs,which sensitize 4T1 tumor cells to immune checkpoint blockade therapy.Therefore,PPC nanospheres inhibit tumor growth efficiently both in situ and distally and blocked the formation of lung metastases.The present study provides a simple and efficient integrated strategy for breast cancer photoimmunotherapy.展开更多
Optical line tweezers have been an efficient tool for the manipulation of large micron particles. In this paper, we propose to create line traps with transformable configurations by using the transverse electromagneti...Optical line tweezers have been an efficient tool for the manipulation of large micron particles. In this paper, we propose to create line traps with transformable configurations by using the transverse electromagnetic mode-like laser source.We designed an optical path to simulate the generation of the astigmatic beams and line traps with a series of lenses to realize the rotational transformation with respect to the rotation angle of cylindrical lenses. It is shown that the spherical particles with diameters ranging from 5 μm to 20 μm could be trapped, aligned, and revolved in experiment. The periodical trapping forces generated by transformable line traps might open an alternative way to investigate the mechanical properties of soft particles and biological cells.展开更多
Most existing biped robots can only walk with their feet or move by wheels.To combine the best of both worlds,this paper introduces the dynamic wheeled control including wheeled locomotion and in-situ wheel-to-foot(Wt...Most existing biped robots can only walk with their feet or move by wheels.To combine the best of both worlds,this paper introduces the dynamic wheeled control including wheeled locomotion and in-situ wheel-to-foot(WtF)transformation of a full-sized wheel-biped transformable robot SR600-II.It can traverse on flat surfaces by wheels and transform to footed stance through its switching modules when facing obstacles.For wheeled locomotion,the kinematics considering upper-body lumped center-of-mass(CoM)constraint is first derived.Then,the dynamics of wheeled locomotion is modeled as a wheeled inverted pendulum(WIP)with variables related to the pose of upper body.After that,a parameter-varying linear quadratic regulator(LQR)controller is utilized to enable dynamic wheeled locomotion.For WtF transformation,the WtF balance constraints are first revealed.Then,a WtF transformation strategy is proposed to tackle the problem when robot transforms from wheeled balance state to in-situ biped stance state.It enables the robot to pass by the transition stages in which both wheels and feet touch the ground and to maintain its balance at the same time.Simulations and experiments on the SR600-II prototype have validated the efficacy of proposed dynamic wheeled control strategies for both wheeled locomotion and in-situ WtF transformation.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51573031,21373726,21303723,21603028 and 21573036)Science Fund for Creative Research Groups of the National Natural Science Foundation of China(No.11621505)+1 种基金CAS Key Research Program for Frontier Sciences(No.QYZDJ-SSW-SLH022)Key Project of Chinese Academy of Sciences in Cooperation with Foreign Enterprises(No.GJHZ1541)
文摘In recent years,various transformable nanoparticles（NPs）were successfully prepared and widely utilized for biomedical applications.The sizes,surface charges or morphologies of transformable NPs would affect their behavior in physiological/pathological conditions including circulation,penetration,accumulation and retention etc.The other way round,the NPs could be precisely modulated in the specific physiological/pathological condition for precision theranostics of diseases.Herein,we summarized recent advances of transformable NPs for disease diagnostics and therapy.In this review,the transformation of NPs was divided into three groups including changes in size,surface charge and morphology,which was induced by internal stimuli,such as p H,enzyme,receptor or external stimuli,such as light,temperature etc.Moreover,we focused on the characterization of structural transformation in vivo,as well as the transformation-induced biological effects for theranostics of disease.
基金was supported by National Natural Science Foundation of China(81972893,82172719)Natural Science Foundation of Henan(212300410071)Training program for young key teachers in Henan Province(2020GGJS019).
文摘Induction of tumor cell senescence has become a promising strategy for anti-tumor immunotherapy,but fibrotic matrix severely blocks senescence inducers penetration and immune cells infiltration.Herein,we designed a cancer-associated fibroblasts(CAFs)triggered structure-transformable nano-assembly(HSD-P@V),which can directionally deliver valsartan(Val,CAFs regulator)and doxorubicin(DOX,senescence inducer)to the specific targets.In detail,DOX is conjugated with hyaluronic acid(HA)via diselenide bonds(Se-Se)to form HSD micelles,while CAFs-sensitive peptide is grafted onto the HSD to form a hydrophilic polymer,which is coated on Val nanocrystals(VNs)surface for improving the stability and achieving responsive release.Once arriving at tumor microenvironment and touching CAFs,HSD-P@V disintegrates into VNs and HSD micelles due to sensitive peptide detachment.VNs can degrade the extracellularmatrix,leading to the enhanced penetration of HSD.HSD targets tumor cells,releases DOX to induce senescence,and recruits effector immune cells.Furthermore,senescent cells are cleared by the recruited immune cells to finish the integrated anti-tumor therapy.In vitro and in vivo results show that the nanoassembly remarkably inhibits tumor growth as well as lungmetastasis,and extends tumorbearing mice survival.This work provides a promising paradigm of programmed delivering multi-site nanomedicine for cancer immunotherapy.
文摘The contemplation of contemporary architectural designs shows an increasing demand for the development of more adaptable, flexible and transformable structures. This type of structures can adapt with different environmental conditions and meet different functions. This can help in reducing environmental waste and pollution associated with many buildings and above all can save on cost and time. Natural systems have inspired human being, since they began to build and design. Architects and designers have utilized nature as one of the main resources of information for the creation of innovative architectural spaces. One of the unique features of natural structures is the way that their components open and close in order to respond to a particular requirement or the environmental changes. This aspect has inspired many designers for the development of transformable architectural structures that can change their shape and geometry to be able to adapt with specific conditions. To make a way toward the design of transformable structure for temporary applications, the authors have developed a new type of adaptable structures according to natural forms. The proposed design applies the transformation principles that exist in potato＇s flower and the movement mechanisms used in a spider＇s leg. The design is able to fit to different topographies and have a potential to be folded to a very compact state in a very short period of time. The detailed design and the different configurations of the system applications will be presented in this paper. The result of the study shows that using modular triangular plates can create a changeable module that is not only able to respond to different functions and environmental changes but it is also able to shape different configuration to be able to respond to different user＇s ambitions. The compactability of this structure into 1/3 of its base dimensions; makes its transportation fast and with minimum costs. These capabilities make this structure suitable for temporary buildings such as exhibitions, temporary settlements or hospital in damaged areas.
文摘Transformable architecture is totally linked to the study and knowledge of geometry.There are some materials in nature,whose geometric invariants establish equivalent structural behavior regarding the scalar transformations,developing different spatial typologies according to dimensional variation.Auxetic materials are characterized by their negative Poisson’s ratio.They can change their geometric configuration from a line to a surface,and from a surface to a volume or spatial framework.This paper is based on establishing and comparing those stellated reentrant auxetic geometries to be able to build new spaces defined by their capacity for architectural transformation,studying analytically geometric properties of stellated reentrant auxetic structures that,from the molecular to the macroscopic level,can be part of the architecture construction.In this investigation,a comparative study by means of CAD of stellated reentrant auxetic patterns has been realized.A Computer-Aided Design study of stellated reentrant auxetic structures will be realized to use them in architecture.The geometric behavior of the different stellated reentrant auxetic patterns is analyzed from the developed study to generate a systematic comparison,evaluating properties of these forms,such as their maximum achievable area reductions in relation to the total length of bars of the structure,in order to obtain a growth factor.
基金We acknowledge financial support by the National Natural Science Foundation of China(32071374,32000985,81761148029,81620108028)Program of Shanghai Academic Research Leader under the Science and Technology Innovation Action Plan(21XD1422100)+3 种基金Leading Talent of“Ten Thousand Plan”-National High-Level Talents Special Support Plan,One Belt and One Road International Cooperation Project from Key Research and Development Program of Zhejiang Province(2019C04024)the Zhejiang Provincial Natural Science Foundation of China(LR22C100001,LGF19C100002,LQ21H300003)Zhejiang Province Medical and Health Science Research Project(2021KY666),and Zhejiang Pharmaceutical Association(2019ZYY12)Open access funding provided by Shanghai Jiao Tong University
文摘The structural change-mediated catalytic activity regulation plays a significant role in the biological functions of natural enzymes.However,there is virtually no artificial nanozyme reported that can achieve natural enzyme-like stringent spatiotemporal structure-based catalytic activity regulation.Here,we report a subnanostructural transformable gold@ceria(STGC-PEG)nanozyme that performs tunable catalytic activities via near-infrared(NIR)light-mediated sub-nanostructural transformation.The gold core in STGC-PEG can generate energetic hot electrons upon NIR irradiation,wherein an internal sub-nanostructural transformation is initiated by the conversion between CeO;and electron-rich state of CeO;-x,and active oxygen vacancies generation via the hot-electron injection.Interestingly,the sub-nanostructural transformation of STGC-PEG enhances peroxidase-like activity and unprecedentedly activates plasmon-promoted oxidase-like activity,allowing highly efficient low-power NIR light(50 m W cm;)-activated photocatalytic therapy of tumors.Our atomic-level design and fabrication provide a platform to precisely regulate the catalytic activities of nanozymes via a light-mediated sub-nanostructural transformation,approaching natural enzyme-like activity control in complex living systems.
基金supported by the National Natural Science Foundation of China(Nos.52171164 and 51790484)National Key Laboratory of Science and Technology on Materials under Shock and Impact(WDZC2022-13)+4 种基金the National Key Research and Development Program of China(No.2021YFA0716303)Start-up research grant(No.SRG/2020/000095)of Science and Engineering Research Board,DST,GoI.A∗STAR,Singapore via the Structural Metals and Alloys Program(No.A18B1b0061)the Natural Science Foundation of Liaoning Province(No.2021-MS-009)the China Manned Space Engineering,the Chinese Academy of Sciences(ZDBS-LY-JSC023)the Youth Innovation Promotion Association CAS(No.2021188).
文摘Developing bulk metallic glass composites(BMGCs)with high toughness is vital for their practical application.However,the influence of different microstructures on the impact toughness of BMGCs is still unclear.The effects of Al addition and cryogenic cyclic treatment(CCT)on the Charpy impact toughness,a K,at 298 and 77 K of a series of phase-transformable BMGCs are investigated in this work.It is found that deformation-induced martensitic transformation(DIMT)of theβ-Ti dendrites is the dominant toughening mechanism in the phase-transformable BMGCs at 298 K,but at 77 K,the toughness of BMGCs is primarily determined by the intrinsic toughness of the glass matrix.The addition of Al can moderately tune theβ-Ti phase stability,which then affects the amount of DIMT and impact toughness of the BMGCs at 298 K.However,at 77 K,Al addition causes a monotonic decrease in the toughness of the BMGCs due to the embrittlement of the glass matrix.It is found that CCT can effectively rejuvenate the phase-transformable BMGCs,which results in an enhanced impact toughness at 298 K.However,the toughness at 77 K monotonously decreases with increasing the number of CCT cycles,suggesting that the rejuvenation of the glass matrix affects the toughness at both 298 and 77 K of BMGCs,but in dramatically different ways.These findings reveal the influence of microstructures and CCT on the impact toughness of BMGCs and provide insights that could be useful for designing tougher BMGs and BMGCs.
文摘The introduction of alleles into commercial crop breeding pipelines is both time consuming and costly.Two technologies that are disrupting traditional breeding processes are doubled haploid(DH)breeding and genome editing(GE).Recently,these techniques were combined into a GE trait delivery system called HI-Edit(Haploid Inducer-Edit).In HI-Edit,the pollen of a haploid inducer line is reprogrammed to deliver GE traits to any variety,obviating recurrent selection.For HI-Edit to operate at scale,an efficient transformable HI line is needed,but most maize varieties are recalcitrant to transformation,and haploid inducers are especially difficult to transform given their aberrant reproductive behaviors.Leveraging marker assisted selection and a three-tiered testing scheme,we report the development of new Iodent and Stiff Stalk maize germplasm that are transformable,have high haploid induction rates,and exhibit a robust,genetically-dominant anthocyanin native trait that may be used for rapid haploid identification.We show that transformation of these elite‘‘HI-Edit”lines is enhanced using the BABYBOOM and WUSCHEL morphogenetic factors.Finally,we evaluate the HI-Edit performance of one of the lines against both Stiff Stalk and non-Stiff Stalk testers.The strategy and results of this study should facilitate the development of commercially scalable HI-Edit systems in diverse crops.
基金supported by the National High Technology Research and Development Program of China ("863" Program) (Grant No. 2007AA041502-5)the Technology and Innovation Fund of the Chinese Academy of Sciences
文摘To maneuver in unstructured terrains where the ground might be soft, hard, flat or rough, a transformable wheel-track robot (NEZA-I) with a self-adaptive mobile mechanism is proposed and developed. The robot consists of a control system unit, two symmetric transformable wheel-track (TWT) units, and a rear-wheel unit. The TWT unit is the main mobile mechanism for the NEZA-I robot, with the rear-wheel unit acting as an assistant mechanism. Driven only by one servomotor, each TWT unit can efficiently select between track mode and wheel mode for optimal locomotion, autonomously switching locomotion mode and track configuration with changes in the terrain. In this paper, the mechanism structure, the self-adaptive drive system, the locomotion mode and posture of the NEZA-I robot are presented, the kinematic relation of the inside parts of the TWT unit is analysed, and the mathematic model of the constraint relation between the mobile mechanism and the ground, abbreviated to "MGCR model" is set up for the NEZA-I robot to go through some typical unstructured environments. The mechanism parameters, which influence the self-adaptability of the NEZA-I robot, are found and optimized. Basic experiments show that the mobile mechanism has the self-adaptability to navigate in unstructured terrains and has superior obstacle-negotiating performance, and that the MGCR model and the analysis method of mechanism parameters are reasonable. From a mechanism point of view, it can provide an idea for research on the adaptive control of the robot.
基金This work was supported by the National Key R&D Program of China(2017YFA0205600)Natural Science Foundation of Hebei Province(H2022206171)。
文摘Mild photothermal therapy combined with immune checkpoint blockade has received increasing attention for the treatment of advanced or metastatic cancers due to its good therapeutic efficacy.However,it remains a challenge to facilely integrate the two therapies and make it potential for clinical translation.This work designed a peptide-photosensitizer conjugate(PPC),which consisted of a PD-L1 antagonist peptide(CVRARTR),an MMP-2 specific cleavable sequence,a self-assembling motif,and the photosensitizer Purpurin 18.The single-component PPC can self-assemble into nanospheres which is suitable for intravenous injection.The PPC nanosphere is cleaved by MMP-2 when it accumulates in tumor sites,thereby initiating the cancer-specific release of the antagonist peptide.Simultaneously,the nanospheres gradually transform into co-assembled nanofibers,which promotes the retention of the remaining parts within the tumor.In vivo studies demonstrated that PPC nanospheres under laser irradiation promote the infiltration of cytotoxic T lymphocytes and maturation of DCs,which sensitize 4T1 tumor cells to immune checkpoint blockade therapy.Therefore,PPC nanospheres inhibit tumor growth efficiently both in situ and distally and blocked the formation of lung metastases.The present study provides a simple and efficient integrated strategy for breast cancer photoimmunotherapy.
基金This work was supported by the National Natural Science Foundation of China(No.61965008)Guangxi Natural Science Foundation(No.AD21220086)+1 种基金Scientific Research Project for Guangxi University(No.2020KY05022)Guangxi Key Laboratory(Nos.YQ21109 and GD21103).
文摘Optical line tweezers have been an efficient tool for the manipulation of large micron particles. In this paper, we propose to create line traps with transformable configurations by using the transverse electromagnetic mode-like laser source.We designed an optical path to simulate the generation of the astigmatic beams and line traps with a series of lenses to realize the rotational transformation with respect to the rotation angle of cylindrical lenses. It is shown that the spherical particles with diameters ranging from 5 μm to 20 μm could be trapped, aligned, and revolved in experiment. The periodical trapping forces generated by transformable line traps might open an alternative way to investigate the mechanical properties of soft particles and biological cells.
文摘Most existing biped robots can only walk with their feet or move by wheels.To combine the best of both worlds,this paper introduces the dynamic wheeled control including wheeled locomotion and in-situ wheel-to-foot(WtF)transformation of a full-sized wheel-biped transformable robot SR600-II.It can traverse on flat surfaces by wheels and transform to footed stance through its switching modules when facing obstacles.For wheeled locomotion,the kinematics considering upper-body lumped center-of-mass(CoM)constraint is first derived.Then,the dynamics of wheeled locomotion is modeled as a wheeled inverted pendulum(WIP)with variables related to the pose of upper body.After that,a parameter-varying linear quadratic regulator(LQR)controller is utilized to enable dynamic wheeled locomotion.For WtF transformation,the WtF balance constraints are first revealed.Then,a WtF transformation strategy is proposed to tackle the problem when robot transforms from wheeled balance state to in-situ biped stance state.It enables the robot to pass by the transition stages in which both wheels and feet touch the ground and to maintain its balance at the same time.Simulations and experiments on the SR600-II prototype have validated the efficacy of proposed dynamic wheeled control strategies for both wheeled locomotion and in-situ WtF transformation.
