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Soft pneumatic actuators are made of flexible materials that deform in response to pressure changes. Due to their reliability, safety, and flexibility, such actuators enable diverse hardware design and become indispensable for soft robots. However, bulky air compressors and pipes constrain their further integration and lightweight. The liquid–vapor phase transition can produce significant encapsulated volume changes and achieve pipeless thermo‐pneumatic actuation. Herein, a novel soft thermoelectric‐based actuator, named Peltier pouch motor (PPM), is presented with modular and dual‐stroke characteristics enabled by active phase transition of low‐boiling‐point liquid. Furthermore, its lightweight and stretchable compliance contributes to assembly‐induced hyper‐modularity to create diverse degrees‐of‐freedom hybrid systems. Finally, the various forms of PPM units are exploited and versatile locomotion is facilitated for five different applications under multi‐medium scenarios, including thermo‐responsive land locomotion, submersible noise‐free hovering, smart curtains control, body‐temperature‐driven wrist rehabilitation, and adaptive hybrid gripper. In these results, it is indicated that the proposed PPM unit advances in hyper‐modularity with excellent performance in high load rate (around 400%), heat transfer efficiency (heating boost, 425%; cooling boost, 138%), and thermal response performance (heating, 0.57° s−1; cooling, 0.29° s−1; 4.5 V), inspiring widely innovative soft robots through the pipeless thermo‐pneumatic actuation. [ABSTRACT FROM AUTHOR]

Introduction: For patients with advanced hepatocellular carcinoma (HCC), hepatic artery infusion chemotherapy (HAIC) is a common and mature treatment, but the safety and efficacy of HAIC combined with lenvatinib for advanced HCC patient treatment remains unclear. Therefore, this study compared the safety and efficacy of HAIC with or without lenvatinib in unresectable HCC patients. Methods: We retrospectively analyzed 13 unresectable advanced HCC patients who received HAIC monotherapy or combination therapy of HAIC and lenvatinib. Overall survival (OS), disease control rate (DCR), objective response rate (ORR), progression-free survival (PFS), incidence of adverse events (AEs), and changes in liver function were compared between the two groups. We applied a Cox regression analysis to evaluate the independent risk factors affecting survival outcomes. Results: The ORR in the HAIC+lenvatinib group was markedly increased compared to the HAIC group (p < 0.05), while the DCR in the HAIC group was higher (p > 0.05). No notable difference was found between the two groups in median OS and PFS (p > 0.05). Compared to the HAIC+lenvatinib group, more patients had improved liver function in the HAIC group after treatment, but the difference was not dramatical (p > 0.05). The AEs incidence was 100.00% in both groups, which was relieved with corresponding treatment. Besides, Cox regression analysis did not identify independent risk factors related to OS and PFS. Conclusion: Combination therapy of HAIC and lenvatinib notably performed better than the HAIC monotherapy in patients with unresectable HCC in terms of ORR and was well tolerated, which deserves further investigation with large-scale clinical trials. [ABSTRACT FROM AUTHOR]

Compared to passive suspensions, active suspensions with electromagnetic linear actuator (EMLA) not only has higher performance in active force control, but also can regenerate energy form road disturbances. In this study, the characteristics of a new designed EMLA were investigated under generator mode by precisely co-simulating the quarter active suspension with single degree of freedom. This model, which consists of sprung mass, EMLA imported from Maxwell and a spring in parallel with the EMLA, is built in Simplorer. Simulation results show that the mechanical power and electric power of the EMLA are both proportional to the frequency and amplitude of excitation. The efficiency, defined as the ratio of electric energy to mechanical energy, decreases with the increase of frequency while nonlinearly changes with the increase of stroke. The yielded maximal efficiency of 94% occur sat the frequency of 2 Hzand the stroke ranges of6mm to 9mm.

With the emerging need for human–machine interactions, multi-modal sensory interaction is gradually pursued rather than satisfying common perception forms (visual or auditory), so developing flexible, adaptive, and stiffness-variable force-sensing devices is the key to further promoting human–machine fusion. However, current sensor sensitivity is fixed and nonadjustable after fabrication, limiting further development. To solve this problem, we propose an origami-inspired structure to achieve multiple degrees of freedom (DoFs) motions with variable stiffness for force-sensing, which combines the ductility and flexibility of origami structures. In combination with the pneumatic actuation, the structure can achieve and adapt the compression, pitch, roll, diagonal, and array motions (five motion modes), which significantly increase the force adaptability and sensing diversity. To achieve closed-loop control and avoid excessive gas injection, the ultra-flexible microfiber sensor is designed and seamlessly embedded with an approximately linear sensitivity of ∼0.35 Ω /kPa at a relative pressure of 0–100 kPa, and an exponential sensitivity at a relative pressure of 100–350 kPa, which can render this device capable of working under various conditions. The final calibration experiment demonstrates that the pre-pressure value can affect the sensor's sensitivity. With the increasing pre-pressure of 65–95 kPa, the average sensitivity curve shifts rightwards around 9 N intervals, which highly increases the force-sensing capability towards the range of 0–2 N. When the pre-pressure is at the relatively extreme air pressure of 100 kPa, the force sensitivity value is around 11.6 Ω /N. Therefore, our proposed design (which has a low fabrication cost, high integration level, and a suitable sensing range) shows great potential for applications in flexible force-sensing development. [ABSTRACT FROM AUTHOR]

Deployable mechanism has received more attention in the medical field due to its simple structure, dexterity, and flexibility. Meanwhile, the advantages of the Magnetic Anchoring and Guidance System (MAGS) are further highlighted by the fact that the operators can remotely control the corresponding active and passive magnetic parts in vivo. Additionally, MAGS allows the untethered manipulation of intracorporeal devices. However, the conventional instruments in MAGS are normally rigid, compact, and less flexible. Therefore, to solve this problem, four novel deployable tubular mechanisms, Design 1 (Omega-shape mechanism), Design 2 (Fulcrum-shape mechanism), Design 3 (Archway-shape mechanism), and Design 4 (Scissor-shape mechanism) in this paper, are proposed integrated with MAGS to realize the laser steering capability. Firstly, this paper introduces the motion mechanism of the four designs and analyzes the motion characterization of each structure through simulation studies. Further, the prototypes of four designs are fabricated using tubular structures with embedded magnets. The actuation success rate, the workspace characterization, the force generation and the load capability of four mechanisms are tested and analyzed based on experiments. Then, the demonstration of direct laser steering via macro setup shows that the four mechanisms can realize the laser steering capability within the error of 0.6 cm. Finally, the feasibility of indirect laser steering via a macro-mini setup is proven. Therefore, such exploration demonstrates that the application of the deployable tubular mechanisms integrated with MAGS towards in vivo treatment is promising. [ABSTRACT FROM AUTHOR]

This paper presents a novel dynamic tactile sensor with a symmetrical longitudinal piezoelectric cantilever structure, which is different from the conventional transverse cantilever structure. It has a radical size of 1.1 centimeters. A flexible hinge chain and mass probe are introduced into the structure to reduce the sensor’s natural frequency to improve the estimation accuracy of tissue hardness. Double piezoelectric patches, symmetrically distributed in the sensor, are used as the actuator to generate vibration and as the sensor for resonance detection. The sensor’s basic working principle is derived mathematically, followed by simulation verification of statics analysis for safety consideration, anisotropic vibration mode analysis, harmonic response analysis, and a calibration experiment to establish fitting curves. The threshold point is set as 192 Hz/0.6 MPa in the calibration curve, and the hardness range is divided into a soft range (0–0.6 MPa) with the sensitivity of 9.75 Hz/MPa, which could realize hardness measurement of soft tissue and normal tissue, and a hard range (which exceeds 0.6 MPa) with higher frequency to realize the identification of the lesion tissue. Finally, the sensor prototype is tested on biological tissue (fresh pig liver) to verify that the calibration curve with the selected threshold is effective for identifying lesion areas and that the sensor prototype has a function of hardness measurement with a relatively stable sensitivity and lesion identification in its operating frequency range. [ABSTRACT FROM AUTHOR]

Intraoperative tumor detection and shape identification through manual palpation are routinely performed in traditional open surgeries to ensure complete tumor resection. However, most existing robot-assisted minimally invasive surgery (RMIS) systems lack tactile feedback and rely on vision heavily. Traditional tactile sensing methods require the sensor to be placed normal to the tissue surface. But this requirement cannot always be met due to the limited degrees of freedom and the complexity of the environment in confined spaces. This paper proposes a miniaturized piezoelectric tactile sensor for tissue hardness detection by measuring its electrical impedance spectrum. It has two unique detection modes in two orthogonal directions—transverse and longitudinal, and can detect hardness even when the contact angle is large. It is verified by simulations and experiments that both detection modes can be used to detect hardness in the normal contact condition. However, in the case of hardness detection at a large contact angle, the sensitivity of the sensor in the transverse detection mode is significantly higher than that in the longitudinal mode, implying that this mode is more suitable for the large-angle detection. The sensor is then tested on silicone phantoms with hard inclusions and also on an ex vivo porcine liver. In addition, a tactile imaging algorithm based on Gaussian process regression is used to generate the complete hardness distribution of the test sample, which is further processed to extract the shape and boundary of the hard inclusion. The results show that the accuracy of shape detection is high (recall ⩾ 95%, specificity ⩾ 97%), and the smallest feature size it could detect is 1.3 mm. This proves that the proposed tactile sensor has the potential to perform high-accuracy tumor detection in RMIS. [ABSTRACT FROM AUTHOR]

Metal additive manufacturing has shown great potential in aerospace, medical, and automobile industries; however, distortion of metal part has been an obstacle in widespread application of metal additive manufacturing. The mechanism of thin-walled structure distortion remains unrevealed. In this study, the origin of distortion of thin-walled structure was discussed, based on the previously proposed assumption of constraining force-induced distortion. The relation between the microstructure and macro-distortion has been linked via the constraining force. The influence of scan directions and structure sizes on the distortion was also studied, and the approaches to decrease the thin-walled structure were discussed. Use of the alternant scan strategy has been validated as an effective approach if the structure sizes cannot be adjusted. [ABSTRACT FROM AUTHOR]

Background: Nonalcoholic fatty liver disease (NAFLD) represents one of the most common forms of liver disease worldwide, and it is always regarded as a consequence of a sedentary, food-abundant lifestyle, sitting for an extended time, and a low physical activity level, which often coincide with chronic and long-lasting psychological stress. A Chinese medicine Sinisan (SNS) may be a potential formula for treating this kind of disease., Methods: In this study, a long-term chronic restraint stress protocol was used to investigate the mechanism underlying stress-induced NALFD. To investigate the effect of SNS treatment on stress-induced NAFLD, we measured the liver and serum values of total cholesterol (TC), triglyceride (TG), liver free fatty acids (FFA), low-density lipoprotein, superoxide dismutase, tumor necrosis factor-α, malondialdehyde, interleukin (IL)-6, and serum values of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase. Results are shown as a mean ± standard deviation. Significant differences between the groups were evaluated using the Student t-test. For multiple comparisons, one-way analysis of variance (ANOVA) was used. If the results of ANOVA indicated significant differences, post hoc analysis was performed with the Tukey test or Dunnett test, and p < 0.05 was considered statistically significant., Results: Long-term chronic stress led to steatosis and non-alcoholic steatohepatitis. Additionally, SNS treatment significantly increased body weight gain (p < 0.01) and sucrose preference (p < 0.001), and it reduced the liver values of TC, TG, and FFA (p < 0.05). SNS also reduced the serum values of AST and ALT (p < 0.001), and the liver value of IL-6 (p < 0.01)., Conclusions: This study's results demonstrate that psychological stress may be a significant risk factor of NAFLD. Furthermore, the traditional Chinese medicine formula SNS may have some beneficial effect in antagonizing psychological stress and stress-related NAFLD.

During the past decade, accumulating evidence from both clinical and experimental studies has indicated that erythropoietin may have antidepressant effects. In addition to the kidney and liver, many organs have been identified as secretory tissues for erythropoietin, including the brain. Its receptor is expressed in cerebral and spinal cord neurons, the hypothalamus, hippocampus, neocortex, dorsal root ganglia, nerve axons, and Schwann cells. These findings may highlight new functions for erythropoietin, which was originally considered to play a crucial role in the progress of erythroid differentiation. Erythropoietin and its receptor signaling through JAK2 activate multiple downstream signaling pathways including STAT5, PI3K/Akt, NF-κB, and MAPK. These factors may play an important role in inflammation and neuroprogression in the nervous system. This is particularly true for the hippocampus, which is possibly related to learning, memory, neurocognitive deficits and mood alterations. Thus, the influence of erythropoietin on the downstream pathways known to be involved in the treatment of depression makes the erythropoietin-related pathway an attractive target for the development of new therapeutic approaches. Focusing on erythropoietin may help us understand the pathogenic mechanisms of depression and the molecular basis of its treatment.