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The deleterious effects and potential therapeutic strategy of fluorene-9-bisphenol on circadian activity and liver diseases in zebrafish and mice

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Journal of Environmental Sciences 2024年第11期145卷 13-27页

作者： Shuhui Zhang Xiang Zuo Jialu Luan Huijuan Bai Zhenhua Fu Mingzhu Sun Xin Zhao Xizeng Feng College of Life Science State Key Laboratory of Medicinal Chemical BiologyThe Key Laboratory of Bioactive MaterialsMinistry of EducationNankai UniversityTianjin 300071China Institute of Robotics&Automatic Information System College of Artificial IntelligenceNankai UniversityTianjin 300071China

Increasing evidence indicates that disturbance of the clock genes,which leads to systemic endocrine perturbation,plays a crucial role in the pathogenesis of metabolic and liver ***-9-bisphenol(BHPF)is utilized in the manufacturing of plastic materials but its biological effects on liver homeostasis remain *** impacts and involved mechanisms of BHPF on the liver diseases,metabolism,and circadian clock were comprehensively studied by zebrafish andmouse *** therapeutic effect of melatonin(MT)was also *** and mousemodels with either acute exposure(0.5 and 1μmol/L,1-4 days post-fertilization)or chronic oral exposure(0.5 and 50 mg/(kg·2 days),30 days)were established with various BHPF ***,we identified a crucial role for estrogenic regulation in liver development and circadian locomotor rhythms damaged by BHPF in a zebrafish *** mice showed chaos in circadian activity through the imbalance of circadian clock component Brain and Muscle Aryl hydrocarbon receptor nuclear translocator-like 1 in the liver and *** liver sexual dimorphic alteration alongwith reduced growth hormone and estrogens played a critical role in damaged glucose metabolism,hepatic inflammation,and fibrosis induced by ***,sleep improvement by exogenous MT alleviated BHPF-related glucose metabolism and liver injury in *** proposed the pathogenesis of metabolic and liver disease resulting from BHPF and promising targeted therapy for livermetabolism disorders associated with endocrine perturbation *** results might play a warning role in the administration of endocrine-disrupting chemicals in everyday life and various industry applications.

关键词： Fluorene-9-bisphenol(BHPF) Melatonin Circadian activity Endocrine perturbation Liver diseases Female behavior Hepatic sexual dimorphism

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Investigation on laser annealing mechanism of fused silica optics polished by CO2 lasers based on fictive temperature distribution 8

Investigation on laser annealing mechanism of fused silica o...

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Advanced Laser Processing and Manufacturing VIII 2024

作者： Zhang, Tianhao Zhao, Linjie Chen, Mingjun Cheng, Jian Yin, Zhaoyang Li, Tianyuan State Key Laboratory of Robotics and System Harbin Institute of Technology Heilongjiang Harbin150001 China

ISBN: (数字)9781510681972

ISBN: (纸本)9781510681965

CO2 laser polishing process can significantly improve the surface quality and the laser-induced damage threshold (LIDT) of fused silica optics. However, due to the thermal history of the laser polishing process, the increment of the fictive temperature inside the modification layer would cause densification and residual stress, which critically affect the surface accuracy and the service life of fused silica optics. In this work, a 3D multi-physical coupling model including temperature, fluid flow and fictive temperature was established. Based on the fictive temperature distribution of the fused silica polished by CO2 lasers, the mechanism of laser annealing on the modified layer was revealed. The annealing results of fused silica were defined as three states including incomplete annealing, perfect annealing and over annealing. Based on the simulation results, the fictive temperature inside the modified layer was completely reduced with no increment of modified layer depth under the perfect annealing state. Additionally, the residual stress and the fictive temperature after the laser annealing were characterized by the Raman spectrum. The fictive temperature was reduced by 16.8 % and the residual stress was effectively reduced. This work can provide theoretical and experimental guidance for the control of surface modification and residual stress of fused silica optics polished by CO2 lasers. © 2024 SPIE.

关键词： Fused silica

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Design of a Novel Macro-Micro Integrated Brain Surgery Robot Based on Modular Parallel Mechanisms

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Chinese Journal of Mechanical Engineering 2024年第5期37卷 349-364页

作者： Hao Zheng Chenbo Liang Feng Gao Chenkun Qi Bingze He Renqiang Liu Longhai Chen State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200030China Institute of Medical Robotics Shanghai Jiao Tong UniversityShanghai 200030China

The advancement and development of medical surgical robots have provided new technological support for brain surgery and neurosurgical procedures,improving the reliability of highly complex and precise *** turn,this urges the design and development of novel surgical robots to possess higher precision,stability,and enhanced motion *** response to this practical demand,this paper introduces a macro-micro integrated medical brain surgery robot system based on the concept of modular PMs(parallel mechanisms),which have a total of 13 active DOFs(degrees of freedom).This system divides the motion process of brain surgery into a large-scale macro-motion space and a small-scale high-precision motion space for design and planning *** introduction of the design concept that combines multiple modular parallel sub-mechanisms has brought a significant level of decoupling characteristics to the mechanism itself.A comprehensive introduction and analysis of the surgical robot are provided,covering aspects such as design,kinematics,motion planning,and performance *** address the pose allocation and coordination of motion between the macro platform and the micro platform,a pose allocation algorithm based on the decoupling and non-decoupling characteristics in various dimensions of the macro-micro platform is *** designed measurement experiments have demonstrated that the repeatability in positioning accuracy of the macro and micro platform reaches the level of micron and submicron *** experiments of motion control and simulated brain electrode implantation validate the excellent performance and stability of the entire surgical robot *** research contributes innovative insights to the development of medical surgical robot systems,particularly in the domain of mechanism design.

关键词： Medical surgical robot Macro-micro integrated system Modular parallel mechanism High-precision robot

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A Real-Time Planning and Control Framework for Robust and Dynamic Quadrupedal Locomotion

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Journal of Bionic Engineering 2023年第4期20卷 1449-1466页

作者： Jun Li Haibo Gao Yuhui Wan Haitao Yu Chengxu Zhou State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin150001China School of Mechanical Engineering University of LeedsLeedsLS29JTUK

Legged locomotion poses significant challenges due to its nonlinear,underactuated and hybrid dynamic *** challenges are exacerbated by the high-speed motion and presence of aerial phases in dynamic legged locomotion,which highlights the requirement for online planning based on current states to cope with uncertainty and *** article proposes a real-time planning and control framework integrating motion planning and whole-body *** the framework,the designed motion planner allows a wider body rotation range and fast reactive behaviors based on the 3-D single rigid body *** addition,the combination of a Bézier curve based trajectory interpolator and a heuristic-based foothold planner helps generate continuous and smooth foot *** developed whole-body controller uses hierarchical quadratic optimization coupled with the full system dynamics,which ensures tasks are prioritized based on importance and joint commands are physically *** performance of the framework is successfully validated in experiments with a torque-controlled quadrupedal robot for generating dynamic motions.

关键词： Bionic robot Legged locomotion Motion planning Whole-body control

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PCE: Multi-Agent Path Finding via Priority-Aware Communication & Experience Learning

IEEE Transactions on Intelligent Vehicles

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IEEE Transactions on Intelligent Vehicles 2024年 1-13页

作者： Gao, Jianqi Li, Yanjie Ye, Zhaohui Wu, Xinyu Department of Guangdong Key Laboratory of Intelligent Morphing Mechanisms and Adaptive Robotics and School of Mechanical Engineering and Automation Harbin Institute of Technology Shenzhen China Guangdong Provincial Key Laboratory of Robotics and Intelligent System Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Shenzhen China

Multi-agent path finding (MAPF) is an essential issue for warehouse automation, where multiple agents plan collision-free paths from the start to goal positions. Reinforcement learning (RL) has been employed to develop partially observable distributed MAPF methods that can be scaled to any number of agents. However, existing RL-based MAPF methods still have some limitations in handling redundant information and avoiding deadlock, resulting in a low success rate or longer makespan. This paper proposes a Priority-aware Communication & Experience learning method (PCE), which combines RL with a novel priority-aware multi-agent communication and a new priority-aware deadlock experience replay to tackle this challenge. To be specific, our innovation encompasses two-fold. Our proposed communication mechanism aims to handle redundant information, which establishes a dynamic communication topology based on agents' priorities and proposes a two-head priority-aware graph attention network to aggregate information. In order to help the agent avoid deadlock, we prioritize the expert experience that solves the deadlock when performing experience replay. We conduct multiple simulation experiments on warehouse-like structured grid maps. Compared with the state-of-the-art RL-based MAPF methods, PCE performs significantly better with a higher success rate and lower makespan in small and large MAPF and higher average throughput in the lifelong MAPF, which can further improve the efficiency of warehouse automation. Finally, we validate PCE using three Turtlebot3-Burger robots, which shows that PCE can be applied in real warehouse automation scenarios. IEEE

关键词： Aggregates

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Characterizing permeability-porosity relationships of porous rocks using a stress sensitivity model in consideration of elastic-structural deformation and tortuosity sensitivity

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3437-3451页

作者： Ronghe Xu Liqin Wang Xiaoli Zhao Yuze Mao MIIT Key Laboratory of Aerospace Bearing Technology and Equipment Harbin Institute of TechnologyHarbin150001China State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin150001China Shanghai Aerospace Control Technology Institute Shanghai201100China

Clarifying the relationship between stress sensitivities of permeability and porosity is of great significance in guiding underground resource *** and more studies focus on how to construct stress sensitivity models to describe the relationship and obtain a comprehensive stress sensitivity of porous ***,the limitations of elastic deformation calculation and incompleteness of considered tortuosity sensitivity lead to the fact that the existing stress sensitivity models are still unsatisfactory in terms of accuracy and ***,a more accurate and generic stress sensitivity model considering elastic-structural deformation of capillary cross-section and tortuosity sensitivity is proposed in this *** elastic deformation is derived from the fractal scaling model and Hooke's *** the effects of elastic-structural deformation on tortuosity sensitivity,an empirical formula is proposed,and the conditions for its applicability are *** predictive performance of the proposed model for the permeability-porosity relationships is validated in several sets of publicly available experimental *** experimental data are from different rocks under different pressure *** mean and standard deviation of relative errors of predicted stress sensitivity with respect to experimental data are 2.63%and 1.91%.Compared with other models,the proposed model has higher accuracy and better predictive generalization *** is also found that the porosity sensitivity exponent a,which can describe permeability-porosity relationships,is 2 when only elastic deformation is considered.a decreases from 2 when structural deformation is also *** addition,a may be greater than 3 due to the increase in tortuosity sensitivity when tortuosity sensitivity is considered even if the rock is not fractured.

关键词： Stress sensitivity model Permeability-porosity relationships Elastic-structural deformation Tortuosity stress sensitivity

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Learning Agile Quadrotor Flight in Restricted Environments with Safety Guarantees

IEEE Transactions on Intelligent Vehicles

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IEEE Transactions on Intelligent Vehicles 2024年第9期9卷 1-8页

作者： Chen, Shiyu Li, Yanjie Lou, Yunjiang Lin, Ke Wu, Xinyu Department of Control Science and Engineering Harbin Institute of Technology Shenzhen and Guangdong Key Laboratory of Intelligent Morphing Mechanisms and Adaptive Robotics Shenzhen China Guangdong Provincial Key Laboratory of Robotics and Intelligent System Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Shenzhen China

With the increasing requirement for agile and efficient controllers in safety-critical scenarios, controllers that exhibit both agility and safety are attracting attention, especially in the aerial robotics domain. This paper focuses on the safety issue of Reinforcement Learning (RL)-based control for agile quadrotor flight in restricted environments. To this end, we propose a unified Adaptive Safety Predictive Corrector (ASPC) to certify each output action of the RL-based controller in real-time, ensuring its safety while maintaining agility. Specifically, we develop the ASPC as a finite-horizon optimal control problem, formulated by a variant of Model Predictive Control (MPC). Given the safety constraints determined by the restricted environment, the objective of minimizing loss of agility can be optimized by reducing the difference between the actions of RL and ASPC. As the safety constraints are decoupled from the RL-based control policy, the ASPC is plug-and-play and can be incorporated into any potentially unsafe controllers. Furthermore, an online adaptive regulator is presented to adjust the safety bounds of the state constraints with respect to the environment changes, extending the proposed ASPC to different restricted environments. Finally, simulations and real-world experiments are demonstrated in various restricted environments to validate the effectiveness of the proposed ASPC. IEEE

关键词： Reinforcement learning

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Data-Driven Robust Model Predictive Control for Pose Tracking of Redundant Manipulators

Data-Driven Robust Model Predictive Control for Pose Trackin...

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2024 IEEE International Conference on robotics and Biomimetics, ROBIO 2024

作者： Chen, Zhaoyang Ni, Fenglei Min, Kang Liu, Hong Harbin Institute of Technology State Key Laboratory of Robotics and System Heilongjiang Province Harbin150001 China

ISBN: (纸本)9781665481090

In this paper, we present a data-driven robust model predictive control (DD-RMPC) method for pose tracking of redundant manipulators. Firstly, a MPC-based trajectory tracking framework is established, in which the joint limits at three different levels (angle, velocity, and acceleration) are satisfied. Secondly, to deal with the system model's uncertainty, accelerate the error convergence speed, and reduce tracking errors, a novel data-driven RMPC is proposed, in which the system's input-output data are used to compensate for the conservatism of the system. Finally, the simulation results on a seven degrees of freedoms (DOFs) redundant manipulator show that DD-RMPC provides a faster error convergence rate and achieves smaller pose tracking errors than that of the comparison methods. © 2024 IEEE.

关键词： Predictive control systems

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A Kinematic Decoupling Whole-body Control Method for a Mobile Humanoid Upper Body Robot

A Kinematic Decoupling Whole-body Control Method for a Mobil...

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2023 International Conference on Frontiers of robotics and Software Engineering, FRSE 2023

作者： Ju, Fengjia Jin, Hongzhe Zhao, Jie Harbin Institute of Technology State Key Laboratory of Robotics and System Harbin China

ISBN: (纸本)9798350301113

The mobile humanoid upper body robot combines the humanoid upper body robot with the mobile platform. It has high redundancy and can complete complex tasks. However, coupling joints, including the waist joints and the mobile platform, exist in the configuration of the robot. During the task execution, the motion of the end-effectors on the dual arms are not independent, but interfere with each other through the motion of the waist and the mobile platform. Therefore, we need to decouple the waist and mobile platform from the dual arms. Based on the pseudo-inverse method of the redundant manipulators, we consider the motion of the coupling joints as a disturbance term and propose a kinematic decoupling whole-body control method. The method realizes the decoupling and cooperation of dual arms, avoids the interference of the inverse kinematics model of the dual arms, and fully releases the application potential of the high redundancy. The decoupling method allows the waist joints and the mobile platform to move randomly without affecting the task operation at the end-effectors, and to further plan their movements separately in order to smooth the whole body motion. The simulations on the mobile humanoid upper body robot verifies our method. © 2023 IEEE.

关键词： End effectors

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A Rigid-Soft Pneumatic Wrist with Fixed Rotation Axes and Active Jamming Variable Stiffness Mechanisms 16th

A Rigid-Soft Pneumatic Wrist with Fixed Rotation Axes and Ac...

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16th International Conference on Intelligent robotics and Applications, ICIRA 2023

作者： Ding, Kehan Jiang, Li Zhen, Ruichen State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin China

ISBN: (纸本)9789819964888

The wrist can greatly enhance the manipulative performance of dexterous hands. In addition, due to the flexibility of soft materials, the soft wrist has obvious advantages in environmental adaptability and safety. However, existing soft wrists often have small motion curvatures and cannot modulate stiffness. Inspired by the human wrist, we proposed a rigid-soft pneumatic wrist design with fixed axes, realizing variable stiffness through jamming mechanisms. The wrist is composed of two rotatory joints in series to achieve pronation/supination and flexion/extension motions. Each joint is driven by two opposite-mounted actuators, resulting in active bidirectional movement. The pre-stretched mounting of pneumatic actuators eliminates the stiffness torque effects. Both joints have independent jamming stiffening mechanisms controlled by air pressure and require no additional power source, which makes the stiffness control more flexible. Experimental results demonstrated that the maximum output torques of the two joints reached 1.18 Nm and 1.40 Nm, and the jamming mechanism increased the stiffness of the joints by 55.3% and 67.2% in the practical test, respectively. The proposed rigid-soft wrist provides a feasible solution for enhancing the manipulative ability of soft dexterous hands. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023.

关键词： Pneumatic actuators

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