Search

Abstract Untethered miniature soft robots have significant application potentials in biomedical and industrial fields due to their space accessibility and safe human interaction. However, the lack of selective and forceful actuation is still challenging in revolutionizing and unleashing their versatility. Here, we propose a focused ultrasound-controlled phase transition strategy for achieving millimeter-level spatially selective actuation and Newton-level force of soft robots, which harnesses ultrasound-induced heating to trigger the phase transition inside the robot, enabling powerful actuation through inflation. The millimeter-level spatial resolution empowers single robot to perform multiple tasks according to specific requirements. As a concept-of-demonstration, we designed soft robot for liquid cargo delivery and biopsy robot for tissue acquisition and patching. Additionally, an autonomous control system is integrated with ultrasound imaging to enable automatic acoustic field alignment and control. The proposed method advances the spatiotemporal response capability of untethered miniature soft robots, holding promise for broadening their versatility and adaptability.

Immiscible displacement in porous media is a crucial microscale flow phenomenon in many fields, necessitating an understanding of the flow mechanisms under dynamic injection velocity and mixing wettability to predict and affect this flow accurately. Initially, a dynamic injection velocity method and a computational domain model considering non-dominant/dominant wetting angles were proposed. Then, microscale flow phenomena were modeled in a pore throat structure and doublet geometry under mixed wetting conditions. Finally, the influence of dynamic injection velocity and mixed wettability on microscale flow were investigated using numerical simulations. The results indicate that when stepwise and piecewise linear changes in injection velocity are observed, unlike continuous injection, two preferential displacement pathways are predominantly formed in the porous media. As the difference between the maximum and minimum injection velocity increases, the recovery efficiency initially decreases and then increases. Recovery efficiency is higher under piecewise linear injection velocity changes. The non-dominant wetting angle determines the distribution and flow of oil-water two-phase systems in porous media. With a dominant controlling wetting angle of 45°, as the non-dominant wetting angle increases, the flow phenomenon changes from one preferential pathway in the back region (30°, 45°) to two preferential pathways (60°, 90°, 120°) and then to one preferential pathway in the middle porous media (150°). As the degree of the non-dominant wetting angle increases, the recovery efficiency first increases and then decreases, with a maximum and minimum difference of 13.6%.

Navigating the intricate and narrow vascular pathways of the body remains a formidable challenge in vascular embolization, often limiting the maneuverability and steerability of traditional catheters. This study, by T.T. Xu and co-workers, introduces dual-responsive reconfigurable miniature fiberbots, which are capable of catheter-assisted deployment, navigation, and embolization in vascular systems. Through meticulous design and magnetic control, this work successfully validates a multistage vascular embolization approach in the renal artery of rabbits in vivo. The experiments not only overcome the existing limitations of conventional catheterization techniques but also open new avenues for minimally invasive treatments.

Introduction: Electromagnetically controlled small-scale robots show great potential in precise diagnosis, targeted delivery, and minimally invasive surgery. The automatic navigation of such robots could reduce human intervention, as well as the risk and difficulty of surgery. However, it is challenging to build a precise kinematics model for automatic robotic control because the controlling process is affected by various delays and complex environments.Method: Here, we propose a learning-based intelligent trajectory planning strategy for automatic navigation of magnetic robots without kinematics modeling. The Long Short-Term Memory (LSTM) neural network is employed to establish a global mapping relationship between the current sequence in the electromagnetic actuation system and the trajectory coordinates.Result: We manually control the robot to move on a curved path 50 times to form the training database to train the LSTM network. The trained LSTM network is validated to output the current sequence for automatically controlling the magnetic robot to move on the same curved path and the tortuous and branched new paths in simulated vascular tracks.Discussion: The proposed trajectory planning strategy is expected to impact the clinical applications of robots.

Direct bioprinting in vivo has the potential to enable new clinical strategies but is currently limited by printing techniques. Here, the authors report on the development of a ferromagnetic soft catheter for magnetic computer controlled minimally invasive bioprinting and demonstrate the printing potential in vivo.

Antibiotic residues and antibiotic resistance genes (ARGs) pose a great threat to public health and food security via the horizontal transfer in the food production chain. Oxidative degradation of amoxicillin (AMO) in aqueous solution by thermally activated persulfate (TAP) was investigated. The AMO degradation followed a pseudo-first-order kinetic model at all tested conditions. The pseudo-first-order rate constants of AMO degradation well-fitted the Arrhenius equation when the reaction temperature ranged from 35°C to 60°C, with the apparent activate energy of 126.9 kJ·mol−1. High reaction temperature, high initial persulfate concentration, low pH, high Cl− concentration, and humic acid (HA) concentration increased the AMO degradation efficiency. The EPR test demonstrated that both ·OH and SO4·− were generated in the TAP system, and the radical scavenging test identified that the predominant reactive radical species were SO4·− in aqueous solution without adjusting the solution pH. In groundwater and drinking water, AMO degradation suggested that TAP could be a reliable technology for water remediation contaminated by AMO in practice.

Swimming training is a kind of aquatic exercise that has been shown to be beneficial to physical fitness at any age. This study aimed to determine how mental and physical aspects of swimming affect aerobic and anaerobic capacity describes the physiological and psychological effects of swimming training at different ages. This study examines how swimming impacts youthful and elderly cardio-respiratory fitness, muscular strength, flexibility, and body composition. A correlation and stepwise regression analysis was performed on the information gathered from a RESTQ-76 sport questionnaire, a Heart Rate Variability (HRV) test, and the efforts of swimmers to improve their aerobic and anaerobic swimming performance. We also investigate the benefits that swimming has on lowering stress, boosting self-esteem, and improving mental health for people of varying ages. We use SPSS version 17.0 was used for the statistical analysis. An examination of the relevant research reveals that swimmers of all ages enjoy significant advantages as a result of their training, including enhancements to their physical and mental health. In that case, they can be able to tailor swimming programs to match the changing physiological and psychological needs of their swimmers. Findings from this study add to a growing body of evidence that open-water swimming is perceived to have positive effects on participants' mental and physical health regardless of age and can be used to inform co-created policy formation to advance outdoor recreation possibilities that are safer, healthier, and more sustainable about this expanding outside activity. [ABSTRACT FROM AUTHOR]