Effects of rotational culture on morphology,nitric oxide production and cell cycle of endothelial cells

Devices for the rotational culture of cells and the study of biological reactions have been widely applied in tissue engineering.However,there are few reports exploring the effects of rotational culture on cell morphology,nitric oxide(NO)production,and cell cycle of the endothelial cells from human umbili-cal vein on the stent surface.This study focuses on these parameters after the cells are seeded on the stents.Results showed that covering of stents by endothelial cells was improved by rotational culture.NO produc-tion decreased within 24 h in both rotational and static culture groups.In addition,rotational culture signifi-cantly increased NO production by 37.9%at 36 h and 28.9%at 48 h compared with static culture.Flow cytometry showed that the cell cycle was not obviously influenced by rotational culture.Results indicate that rotational culture may be helpful for preparation of cell-seeded vascular grafts and intravascular stents,which are expected to be the most frequently implanted materials in the future.

HeterBot:A heterogeneous mobile manipulation robot for versatile operation

This study presents the overall architecture of HeterBot,a heterogeneous mobile manipulation robot developed in our lab,which is designed for versatile operation in hazardous environments.The most significant feature of HeterBot is the heterogeneous design created by adopting the idea of‘big arm+small arm’and‘big car+mini car’.This combination has the advantage of functional complementation,which achieves performance promotion in both locomotion and manipulation capabilities,making HeterBot distinguished from other mobile manipulation robots.Besides,multiple novel technologies are integrated into HeterBot to expand its versatility and ease of use,including Virtual Robot Experimentation Platform-based teleoperation,reconfigurable end effectors,laseraided grasping,and manipulation with customised tools.Experimental results validate the effectiveness of HeterBot in various locomotion and manipulation tasks.HeterBot displays huge potential in future applications,such as searching and rescue.

Design and control of a robotic system with legs,wheels,and a reconfigurable arm

Unmanned robotic systems are expected to liberate people from heavy,monotonous,and dangerous work.However,it is still difficult for robots to work in complicated environments and handle diverse tasks.To this end,a robotic system with four legs,four wheels,and a reconfigurable arm is designed.Special attention has been given to making the robot compact,agile,and versatile.Firstly,by using separate wheels and legs,it removes the coupling in the traditional wheeled–legged system and guarantees highly efficient locomotion in both the wheeled and legged modes.Secondly,a leg–arm reconfiguration design is adopted to extend the manipulation capability of the system,which not only reduces the total weight but also allows for dexterous manipulation and multi-limb cooperation.Thirdly,a multi-task control strategy based on variable configurations is proposed for the system,which greatly enhances the adaptability of the robot to complicated environments.Experimental results are given,which validate the effectiveness of the system in mobility and operation capability.