Bio-inspired visual systems have garnered significant attention in robotics owing to their energy efficiency,rapid dynamic response,and environmental adaptability.Among these,event cameras-bio-inspired sensors that as...Bio-inspired visual systems have garnered significant attention in robotics owing to their energy efficiency,rapid dynamic response,and environmental adaptability.Among these,event cameras-bio-inspired sensors that asynchronously report pixel-level brightness changes called’events’,stand out because of their ability to capture dynamic changes with minimal energy consumption,making them suitable for challenging conditions,such as low light or high-speed motion.However,current mapping and localization methods for event cameras depend primarily on point and line features,which struggle in sparse or low-feature environments and are unsuitable for static or slow-motion scenarios.We addressed these challenges by proposing a bio-inspired vision mapping and localization method using active LED markers(ALMs)combined with reprojection error optimization and asynchronous Kalman fusion.Our approach replaces traditional features with ALMs,thereby enabling accurate tracking under dynamic and low-feature conditions.The global mapping accuracy significantly improved by minimizing the reprojection error,with corner errors reduced from 16.8 cm to 3.1 cm after 400 iterations.The asynchronous Kalman fusion of multiple camera pose estimations from ALMs ensures precise localization with a high temporal efficiency.This method achieved a mean translation error of 0.078 m and a rotational error of 5.411°while evaluating dynamic motion.In addition,the method supported an output rate of 4.5 kHz while maintaining high localization accuracy in UAV spiral flight experiments.These results demonstrate the potential of the proposed approach for real-time robot localization in challenging environments.展开更多
Introduction Stroke or heart attack,the leading cause of death and disability worldwide,is usually caused by rupture of atheromatous plaque.Therefore,the identification of vulnerable atheroma pre rupture has become ex...Introduction Stroke or heart attack,the leading cause of death and disability worldwide,is usually caused by rupture of atheromatous plaque.Therefore,the identification of vulnerable atheroma pre rupture has become extremely important for patient risk stratification.Previous studies have shown that the vulnerable plaque,i.e.one that is prone to rupture with thromboembolic complications,is often associated with a thin fibrous cap,a large lipid core and a high inflammatory burden.The mechanism of plaque rupture is not entirely clear but is thought to be a multi-factorial process involving thinning and weakening of the fibrous cap by enzymes secreted by activa-展开更多
Introduction and research overview Recently,increasing need for organ transplantation and lack of donated organs have led to the rapid development of new technologies for artificial organ biofabrication.In the era of ...Introduction and research overview Recently,increasing need for organ transplantation and lack of donated organs have led to the rapid development of new technologies for artificial organ biofabrication.In the era of burgeoning breakthroughs around 3D bioprinting technologies,the personalization of organs and medicine is an ongoing nice vision[1–5].As one of the leading laboratories in the interdisciplinary field of materials,manufacturing and bioengineering,the Biofabrication(3D Bioprinting)Research Laboratory at Sichuan University has been engaging in the research on customized regenerativemedicine since 2012.展开更多
Lower-limb assisted exoskeletons are widely researched for movement assistance or rehabilitation training.Due to advantages of compliance with human body and lightweight,some cable-driven prototypes have been develope...Lower-limb assisted exoskeletons are widely researched for movement assistance or rehabilitation training.Due to advantages of compliance with human body and lightweight,some cable-driven prototypes have been developed,but most of these can assist only unidirectional movement.In this paper we present an untethered cable-driven ankle exoskeleton that can achieve plantarflexion-dorsiflexion bidirectional motion bilaterally using a pair of single motors.The main weights of the exoskeleton,i.e.,the motors,power supplement units,and control units,were placed close to the proximity of the human body,i.e.,the waist,to reduce the redundant rotation inertia which would apply on the wearer’s leg.A cable force transmission system based on gear-pulley assemblies was designed to transfer the power from the motor to the end-effector effectively.A cable self-tension device on the power output unit was designed to tension the cable during walking.The gait detection system based on a foot pressure sensor and an inertial measurement unit(IMU)could identify the gait cycle and gait states efficiently.To validate the power output performance of the exoskeleton,a torque tracking experiment was conducted.When the subject was wearing the exoskeleton with power on,the muscle activity of the soleus was reduced by 5.2%compared to the state without wearing the exoskeleton.This preliminarily verifies the positive assistance effect of our exoskeleton.The study in this paper demonstrates the promising application of a lightweight cable-driven exoskeleton on human motion augmentation or rehabilitation.展开更多
Epithelial ovarian cancer(EOC) exhibits strong dependency on the tricarboxylic acid(TCA) cycle and oxidative phosphorylation to fuel anabolic process.Here,we show that malate dehydrogenase 2(MDH2),a key enzyme of the ...Epithelial ovarian cancer(EOC) exhibits strong dependency on the tricarboxylic acid(TCA) cycle and oxidative phosphorylation to fuel anabolic process.Here,we show that malate dehydrogenase 2(MDH2),a key enzyme of the TCA cycle,is palmitoylated at cysteine 138(C138) residue,resulting in increased activity of MDH2.We next identify that ZDHHC18 acts as a palmitoyltransferase of MDH2.Glutamine deprivation enhances MDH2 palmitoylation by increasing the binding between ZDHHC18 and MDH2.MDH2 silencing represses mitochondrial respiration as well as ovarian cancer cell proliferation both in vitro and in vivo.Intriguingly,re-expression of wild-type MDH2,but not its palmitoylation-deficient C138 S mutant,sustains mitochondrial respiration and restores the growth as well as clonogenic capability of ovarian cancer cells.Notably,MDH2 palmitoylation level is elevated in clinical cancer samples from patients with high-grade serous ovarian cancer.These observations suggest that MDH2 palmitoylation catalyzed by ZDHHC18 sustains mitochondrial respiration and promotes the malignancy of ovarian cancer,yielding possibilities of targeting ZDHHC18-mediated MDH2 palmitoylation in the treatment of EOC.展开更多
The performance of Aquatic Unmanned Aerial Vehicle(AquaUAV)has always been limited so far and far from practical applications,due to insufficient propulsion,large-resistance structure etc.Aerial-aquatic amphibians in ...The performance of Aquatic Unmanned Aerial Vehicle(AquaUAV)has always been limited so far and far from practical applications,due to insufficient propulsion,large-resistance structure etc.Aerial-aquatic amphibians in nature may facilitate the development of AquaUAV since their excellent amphibious locomotion capabilities evolved under long-term natural selection.This article will take four typical aerial-aquatic amphibians as representatives,i.e.,gannet,cormorant,flying fish and flying squid.We summarized the multi-mode locomotion process of common aerial-aquatic amphibians and the evolutionary trade-offs they have made to adapt to amphibious environments.The four typical propulsion mechanisms were investigated,which may further inspire the propulsion design of the AquaUAV.And their morphological models could guide the layout optimization.Finally,we reviewed the state of art in AquaUAV to validate the potential value of our bioinspiration,and discussed the futureprospects.展开更多
基金Supported by Beijing Natural Science Foundation(Grant No.L231004)Young Elite Scientists Sponsorship Program by CAST(Grant No.2022QNRC001)+2 种基金Fundamental Research Funds for the Central Universities(Grant No.2025JBMC039)National Key Research and Development Program(Grant No.2022YFC2805200)National Natural Science Foundation of China(Grant No.52371338).
文摘Bio-inspired visual systems have garnered significant attention in robotics owing to their energy efficiency,rapid dynamic response,and environmental adaptability.Among these,event cameras-bio-inspired sensors that asynchronously report pixel-level brightness changes called’events’,stand out because of their ability to capture dynamic changes with minimal energy consumption,making them suitable for challenging conditions,such as low light or high-speed motion.However,current mapping and localization methods for event cameras depend primarily on point and line features,which struggle in sparse or low-feature environments and are unsuitable for static or slow-motion scenarios.We addressed these challenges by proposing a bio-inspired vision mapping and localization method using active LED markers(ALMs)combined with reprojection error optimization and asynchronous Kalman fusion.Our approach replaces traditional features with ALMs,thereby enabling accurate tracking under dynamic and low-feature conditions.The global mapping accuracy significantly improved by minimizing the reprojection error,with corner errors reduced from 16.8 cm to 3.1 cm after 400 iterations.The asynchronous Kalman fusion of multiple camera pose estimations from ALMs ensures precise localization with a high temporal efficiency.This method achieved a mean translation error of 0.078 m and a rotational error of 5.411°while evaluating dynamic motion.In addition,the method supported an output rate of 4.5 kHz while maintaining high localization accuracy in UAV spiral flight experiments.These results demonstrate the potential of the proposed approach for real-time robot localization in challenging environments.
基金partially supported by the National 973 Basic Research Program of China (No.2013CB733803)the National Natural Science Foundation of China(NSFC)(No.11272091)
文摘Introduction Stroke or heart attack,the leading cause of death and disability worldwide,is usually caused by rupture of atheromatous plaque.Therefore,the identification of vulnerable atheroma pre rupture has become extremely important for patient risk stratification.Previous studies have shown that the vulnerable plaque,i.e.one that is prone to rupture with thromboembolic complications,is often associated with a thin fibrous cap,a large lipid core and a high inflammatory burden.The mechanism of plaque rupture is not entirely clear but is thought to be a multi-factorial process involving thinning and weakening of the fibrous cap by enzymes secreted by activa-
文摘Introduction and research overview Recently,increasing need for organ transplantation and lack of donated organs have led to the rapid development of new technologies for artificial organ biofabrication.In the era of burgeoning breakthroughs around 3D bioprinting technologies,the personalization of organs and medicine is an ongoing nice vision[1–5].As one of the leading laboratories in the interdisciplinary field of materials,manufacturing and bioengineering,the Biofabrication(3D Bioprinting)Research Laboratory at Sichuan University has been engaging in the research on customized regenerativemedicine since 2012.
基金Project supported by the National Natural Science Foundation of China(No.61703023)Beijing Municipal Natural Science Foundation,China(No.3184054)+1 种基金China Scholarship Council(No.201706025021)National Undergraduate Training Programs for Innovation and Entrepreneurship(No.201910006118)。
文摘Lower-limb assisted exoskeletons are widely researched for movement assistance or rehabilitation training.Due to advantages of compliance with human body and lightweight,some cable-driven prototypes have been developed,but most of these can assist only unidirectional movement.In this paper we present an untethered cable-driven ankle exoskeleton that can achieve plantarflexion-dorsiflexion bidirectional motion bilaterally using a pair of single motors.The main weights of the exoskeleton,i.e.,the motors,power supplement units,and control units,were placed close to the proximity of the human body,i.e.,the waist,to reduce the redundant rotation inertia which would apply on the wearer’s leg.A cable force transmission system based on gear-pulley assemblies was designed to transfer the power from the motor to the end-effector effectively.A cable self-tension device on the power output unit was designed to tension the cable during walking.The gait detection system based on a foot pressure sensor and an inertial measurement unit(IMU)could identify the gait cycle and gait states efficiently.To validate the power output performance of the exoskeleton,a torque tracking experiment was conducted.When the subject was wearing the exoskeleton with power on,the muscle activity of the soleus was reduced by 5.2%compared to the state without wearing the exoskeleton.This preliminarily verifies the positive assistance effect of our exoskeleton.The study in this paper demonstrates the promising application of a lightweight cable-driven exoskeleton on human motion augmentation or rehabilitation.
基金supported by the National Key Research and Development Program of China (2020YFA0803402 and2019YFA0801703)the National Natural Science Foundation of China(81872240,81802745,81790250/81790253 and 91959202)Innovation Program of Shanghai Municipal Education Commission (N173606)。
文摘Epithelial ovarian cancer(EOC) exhibits strong dependency on the tricarboxylic acid(TCA) cycle and oxidative phosphorylation to fuel anabolic process.Here,we show that malate dehydrogenase 2(MDH2),a key enzyme of the TCA cycle,is palmitoylated at cysteine 138(C138) residue,resulting in increased activity of MDH2.We next identify that ZDHHC18 acts as a palmitoyltransferase of MDH2.Glutamine deprivation enhances MDH2 palmitoylation by increasing the binding between ZDHHC18 and MDH2.MDH2 silencing represses mitochondrial respiration as well as ovarian cancer cell proliferation both in vitro and in vivo.Intriguingly,re-expression of wild-type MDH2,but not its palmitoylation-deficient C138 S mutant,sustains mitochondrial respiration and restores the growth as well as clonogenic capability of ovarian cancer cells.Notably,MDH2 palmitoylation level is elevated in clinical cancer samples from patients with high-grade serous ovarian cancer.These observations suggest that MDH2 palmitoylation catalyzed by ZDHHC18 sustains mitochondrial respiration and promotes the malignancy of ovarian cancer,yielding possibilities of targeting ZDHHC18-mediated MDH2 palmitoylation in the treatment of EOC.
基金supported by the National Science Foundation of China(62103035)Beijing Natural Science Foundation(3222016)+1 种基金the China Postdoctoral Science Foundation(2021M690337)the Young Elite Scientists Sponsorship Program by CAST(2022QNRC001)。
文摘The performance of Aquatic Unmanned Aerial Vehicle(AquaUAV)has always been limited so far and far from practical applications,due to insufficient propulsion,large-resistance structure etc.Aerial-aquatic amphibians in nature may facilitate the development of AquaUAV since their excellent amphibious locomotion capabilities evolved under long-term natural selection.This article will take four typical aerial-aquatic amphibians as representatives,i.e.,gannet,cormorant,flying fish and flying squid.We summarized the multi-mode locomotion process of common aerial-aquatic amphibians and the evolutionary trade-offs they have made to adapt to amphibious environments.The four typical propulsion mechanisms were investigated,which may further inspire the propulsion design of the AquaUAV.And their morphological models could guide the layout optimization.Finally,we reviewed the state of art in AquaUAV to validate the potential value of our bioinspiration,and discussed the futureprospects.
