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Ensuring safe and efficient navigation in crowded environments is a critical goal for assistive robots. Recent studies have emphasized the potential of deep reinforcement learning techniques to enhance robots' navigation capabilities in the presence of crowds. However, current deep reinforcement learning methods often face the challenge of robots freezing as crowd density increases. To address this issue, a novel risk-aware deep reinforcement learning approach is proposed in this paper. The proposed method integrates a risk function to assess the probability of collision between the robot and pedestrians, enabling the robot to proactively prioritize pedestrians with a higher risk of collision. Furthermore, the model dynamically adjusts the fusion strategy of learning-based and risk-aware-based features, thereby improving the robustness of robot navigation. Evaluations were conducted to determine the effectiveness of the proposed method in both low- and high-crowd density settings. The results exhibited remarkable navigation success rates of 98.0% and 93.2% in environments with 10 and 20 pedestrians, respectively. These findings emphasize the robust performance of the proposed method in successfully navigating through crowded spaces. Additionally, the approach achieves navigation times comparable to those of state-of-the-art methods, confirming its efficiency in accomplishing navigation tasks. The generalization capability of the method was also rigorously assessed by subjecting it to testing in crowd environments exceeding the training density. Notably, the proposed method attains an impressive navigation success rate of 90.0% in 25-person environments, surpassing the performance of existing approaches and establishing itself as a state-of-the-art solution. This result highlights the versatility and effectiveness of the proposed method in adapting to various crowd densities and further reinforces its applicability in real-world scenarios. [ABSTRACT FROM AUTHOR]

The magnetic field modulated gear is a new technology,compared with the traditional mechanical gear,it can effectively avoid vibration,noise,lubrication and other issues. But its stiffness is low,which will lead to the transient oscillations undergoing the torque of prime motor is disturbance or the velocity changes.Based on the analysis of the basic principle of magnetic gear,a magnetic field modulated gear is designed,whose transmission ratio is 5. 5,and the performance of the magnetic gear with different structures is analyzed by using the electromagnetic field finite element method. A structure type with the highest efficiency is selected,in the iron core of high speed mover of selected gear by introducing damping winding with closed loop,in the process of transient oscillations,the current will be induced in the damping winding,which will produce damping electromagnetic torque can inhibit the mechanical vibration of transmission shaft and maintain the stability of system. In addition,the influence and variation law of the damping wingding parameters on the transient characteristics of magnetic gear are analyzed.

In modern integrated circuit manufacturing processes, wafers are always transported from one procedure to another. To reduce the risk of dust, Front Opening Unified Pod (FOUP) load-port system is always adopted. Misplaced wafers should be detected before transported. Traditional methods always fail to detect wafer states correctly. To improve detection accuracy, this paper proposed a vision based method. Wafer overlap and malposition detection approach based on modified YOLO-V3 algorithm was suggested. Experiment results shows superiority of the proposed approach.

The precise localization of unmanned ground vehicles (UGVs) in industrial parks without prior GPS measurements presents a significant challenge. Simultaneous localization and mapping (SLAM) techniques can address this challenge by capturing environmental features, using sensors for real-time UGV localization. In order to increase the real-time localization accuracy and efficiency of UGVs, and to improve the robustness of UGVs' odometry within industrial parks—thereby addressing issues related to UGVs' motion control discontinuity and odometry drift—this paper proposes a tightly coupled LiDAR-IMU odometry method based on FAST-LIO2, integrating ground constraints and a novel feature extraction method. Additionally, a novel maintenance method of prior maps is proposed. The front-end module acquires the prior pose of the UGV by combining the detection and correction of relocation with point cloud registration. Then, the proposed maintenance method of prior maps is used to hierarchically and partitionally segregate and perform the real-time maintenance of the prior maps. At the back-end, real-time localization is achieved by the proposed tightly coupled LiDAR-IMU odometry that incorporates ground constraints. Furthermore, a feature extraction method based on the bidirectional-projection plane slope difference filter is proposed, enabling efficient and accurate point cloud feature extraction for edge, planar and ground points. Finally, the proposed method is evaluated, using self-collected datasets from industrial parks and the KITTI dataset. Our experimental results demonstrate that, compared to FAST-LIO2 and FAST-LIO2 with the curvature feature extraction method, the proposed method improved the odometry accuracy by 30.19% and 48.24% on the KITTI dataset. The efficiency of odometry was improved by 56.72% and 40.06%. When leveraging prior maps, the UGV achieved centimeter-level localization accuracy. The localization accuracy of the proposed method was improved by 46.367% compared to FAST-LIO2 on self-collected datasets, and the located efficiency was improved by 32.33%. The z-axis-located accuracy of the proposed method reached millimeter-level accuracy. The proposed prior map maintenance method reduced RAM usage by 64% compared to traditional methods. [ABSTRACT FROM AUTHOR]

To address the time-optimal trajectory planning (TOTP) problem with joint jerk constraints in a Cartesian coordinate system, we propose a time-optimal path-parameterization (TOPP) algorithm based on nonlinear optimization. The key insight of our approach is the presentation of a comprehensive and effective iterative optimization framework for solving the optimal control problem (OCP) formulation of the TOTP problem in the (s , s ˙) -phase plane. In particular, we identify two major difficulties: establishing TOPP in Cartesian space satisfying third-order constraints in joint space, and finding an efficient computational solution to TOPP, which includes nonlinear constraints. Experimental results demonstrate that the proposed method is an effective solution for time-optimal trajectory planning with joint jerk limits, and can be applied to a wide range of robotic systems. [ABSTRACT FROM AUTHOR]

Accurately detecting suitable grasp areas for unknown objects through visual information remains a challenging task. Drawing inspiration from the success of the Vision Transformer in vision detection, the hybrid Transformer-CNN architecture for robotic grasp detection, known as HTC-Grasp, is developed to improve the accuracy of grasping unknown objects. The architecture employs an external attention-based hierarchical Transformer as an encoder to effectively capture global context and correlation features across the entire dataset. Furthermore, a channel-wise attention-based CNN decoder is presented to adaptively adjust the weight of the channels in the approach, resulting in more efficient feature aggregation. The proposed method is validated on the Cornell and the Jacquard dataset, achieving an image-wise detection accuracy of 98.3% and 95.8% on each dataset, respectively. Additionally, the object-wise detection accuracy of 96.9% and 92.4% on the same datasets are achieved based on this method. A physical experiment is also performed using the Elite 6Dof robot, with a grasping accuracy rate of 93.3%, demonstrating the proposed method's ability to grasp unknown objects in real scenarios. The results of this study indicate that the proposed method outperforms other state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Gastric cancer is the third most commonly cause of tumour-related death worldwide and one of the most prevalent malignancies in China. TCL1A, TCL1 family Akt coactivator A, can active Akt/mTOR pathway and regulate the autophagy. However, the action of TCL1A in gastric cancer is not well understood. The present study is investigating the mechanism of action of TCL1A in gastric cancer. TCL1A was lowly expressed in gastric cancer tissues. Subsequent experiments demonstrated that miR-181a-5p can regulate c-MYC through the TCL1A-Akt/mTOR pathway and c-MYC can in turn affect the expression of miR-181a-5p, thus confirming the existence of the miR-181a-5p-TCL1A-Akt/mTOR-c-MYC loop. Flow cytometric apoptosis assay and mRFP-eGFP-LC3 autophagy assay demonstrated that both miR-181a-5p and TCL1A can affect autophagy and apoptosis of gastric cancer cells through the loop. In vivo experiments confirmed that TCL1A can affect the proliferation of gastric cancer. These results illustrate that TCL1A can exert tumour suppressive effects and affect gastric cancer autophagy and progression via the miR-181a-5p-TCL1A-Akt/mTOR-c-MYC loop, which could be a potential therapeutic target for gastric cancer. [ABSTRACT FROM AUTHOR]

Wheat production is dramatically influenced by temperature. Low-temperature stress that frequently occurs seriously hampers the growth and development of wheat seedlings. In order to alleviate the damage of low temperature to wheat plant growth, remedial nitrogen was applied prior to or post low-temperature stress at seedling stage using controlled-temperature incubators to explore the difference in wheat morphology and nitrogen absorption and utilization efficiency. Nitrogen amendment significantly increased the leaf area, seedling height, tiller number and dry matter weight of wheat plants as compared with the treatment without nitrogen amendment under temperature stress. Remedial nitrogen applied prior to low-temperature stress (N-LT) was more conducive to increase the above parameters than that applied post low-temperature stress (LT-N). In addition, N-LT enhanced the ability of roots to absorb remedial 15N urea, promoted the growth and development of wheat plants under low-temperature stress, resulting in higher leaf SPAD readings, more new tillers, as well as increased dry weight of roots and above-ground organs. This study suggested that remedial nitrogen should be applied prior to low-temperature stress because it is more effective in restoring the growth of wheat plants under low-temperature stress. [ABSTRACT FROM AUTHOR]

In order to explore the effects of dexmedetomidine (DEX) on functional magnetic resonance imaging (fMRI) and emergence agitation of patients who underwent general anesthesia surgery with sevoflurane under comfortable nursing intervention, 66 patients who received upper abdominal surgery were selected as research objects. According to nursing and anesthesia methods, the patients were randomly divided into control group (routine nursing and anesthesia), group A (routine nursing and DEX-assisted anesthesia), and group B (comfortable nursing and DEX-assisted anesthesia). The differences in the brain fMRI characteristics, hemodynamic indexes, anesthesia recovery indexes, and nursing satisfaction in the perioperative period were evaluated. The results showed that the regional homogeneity values were different in different brain regions, but there was no difference in the Z value of functional connectivity P > 0.05 . Compared with the control group, heart rate, mean arterial pressure, awakening time, extubation time, the Riker sedation-agitation scale (SAS) score, and anesthetic dosage were signally decreased in group A and group B, while the Ramsay scores, the postanesthesia care unit (PACU) stay, and anesthesia maintenance time in the two groups was obviously increased P < 0.05 . Compared with group A, the extubation time, the SAS score, PACU stay, and hospital stay were all remarkably reduced in group B, while the nursing satisfaction score was greatly increased P < 0.05 . To sum up, DEX was helpful to safely and effectively reduce the occurrence of emergence agitation in patients under general anesthesia surgery with sevoflurane. Besides, comfortable nursing intervention could further reduce the incidence of emergence agitation in patients with general anesthesia, shorten the length of hospital stay, and improve nursing satisfaction. [ABSTRACT FROM AUTHOR]

With the rapid development of robot perception and planning technology, robots are gradually getting rid of fixed fences and working closely with humans in shared workspaces. The safety of human-robot coexistence has become critical. Traditional motion planning methods perform poorly in dynamic environments where obstacles motion is highly uncertain. In this paper, we propose an efficient online trajectory generation method to help manipulator autonomous planning in dynamic environments. Our approach starts with an efficient kinodynamic path search algorithm that considers the links constraints and finds a safe and feasible initial trajectory with minimal control effort and time. To increase the clearance between the trajectory and obstacles and improve the smoothness, a trajectory optimization method using the B-spline convex hull property is adopted to minimize the penalty of collision cost, smoothness, and dynamical feasibility. To avoid the collisions between the links and obstacles and the collisions of the links themselves, a constraint-relaxed links collision avoidance method is developed by solving a quadratic programming problem. Compared with the existing state-of-the-art planning method for dynamic environments and advanced trajectory optimization method, our method can generate a smoother, collision-free trajectory in less time with a higher success rate. Detailed simulation comparison experiments, as well as real-world experiments, are reported to verify the effectiveness of our method. [ABSTRACT FROM AUTHOR]

Objective Objective To study the effect of BushenAntai ( BSAT) Granule on Transforming Growth Factor β1(TGF-β1), Phosphatidylinositol-3-kinase( PI3K) and serine/threonine ( AKT) related proteins in decidua of mice with recurrent spontaneous abortion, and to explore its mechanism of reducing the rate of embryo abortion. Methods CBA/J x BALB/c mice were caged to establish normal pregnant mice model. The RSA mice model was established by using DBA/2 x CBA mice, which were randomly divided into model group, progesterone group, BushenAntai ( BSAT) high dose group, BushenAntai (BSAT)medium-dose group and BushenAntai(BSAT)low-dose group. Each group was gavaged with the corresponding medicine daily. After 15 days of continuous intervention, mice were executed and samples were collected, in each group, the embryo loss was observed by naked eyes; Pathological changes of decidua were observed by hematoxylin eosinstaining. The contents of E2, P, TGF-β1, PI3K and Akt in serum of mice in each group were detected by enzyme-linked immunosorbent assay ( ELISA). The expression of TGF-β1, PI3K and Akt in decidua was detected by immunohistochemistry and Western blot. Result Compared with the normal group, in the model group the rate of embryo loss was increased (P<0.01), the contents of E2, P, TGF-pl, PI3K and Akt in serum were decreased (P<0.01), the expression levels of TGF-β1, PI3K and Akt in decidua were decreased (P <0. 01) . Compared with the model group, after drug intervention, the rate of embryo loss was decreased ( P < 0. 01), the contents of E2, P, TGF-β1, PI3K and Akt in serum were increased (P <0. 01), and the expression levels of TGF-β1, PI3K and Akt in decidua were all increased (P <0. 01 ), all of which were most significant in the BSAT high-dose group. Conclusion BSAT Granule is likely to reduce the rate of embryo loss in mice with recurrent spontaneous abortion. Its mechanism may be that through up-regulating TGF-β1/PI3K/Akt signaling pathway, it could promote the formation of blood vessels at the maternal fetal interface of mice with recurrent spontaneous abortion, so as to achieve the purpose of embryo protection. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate a method for quadruped dynamic locomotion based on centroidal momentum control. Our method relies on a quadratic program that solves an optimal control problem to track the reference rate of change of centroidal momentum as closely as possible while satisfying the dynamic, input, and contact constraints of the full quadruped robot dynamics. Given the desired footstep positions, the according reference rate of change of the centroidal momentum is formulated as a feedback control task derived from the CoM motions of a simplified model (linear inverted pendulum) based on Capture Point dynamics. The joint accelerations and the Ground Reaction Forces(GRFs) outputted from the quadratic program solver are used to calculate the desired joint torques using an inverse dynamics algorithm. The performance of the proposed method is tested in simulation and on real hardware. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the inhibitory effects of the polyphenol epigallocatechin-3-gallate (EGCG) on the growth of cervical carcinoma cell lines infected with different high-risk human papillomavirus (HPV) subtypes, as well as the associated regulation of microRNA (miR) expression. Cell proliferation was measured using an MTT assay. The effects of 7 different concentrations of EGCG (100, 80, 60, 40, 20, 10 and 0 µg/ml) on HeLa cell proliferation were assessed. HeLa cell growth was significantly inhibited by EGCG in a dose- and time-dependent manner (P<0.05), and the IC50 was 90.74 and 72.74 µg/ml at 24 and 48 h, respectively. The expression of miR-210, miR-29a, miR-203 and miR-125b in HeLa (HPV16/18+), SiHa (HPV16+), CaSki (HPV16+) and C33A (HPV-) cell lines was measured using quantitative polymerase chain reaction analysis. In CA33 cells, miR-203 (all P<0.001) and miR-125b (P<0.01 and <0.0001) were significantly downregulated by EGCG, and miR-210 was significantly upregulated with 40 and 60 µg/ml EGCG (P<0.0001). miR-125b was significantly downregulated (P<0.001 and <0.0001), and miR-210 and miR-29 were significantly upregulated by ≤80 µg/ml EGCG in HeLa cells (all P<0.0001). In CaSki cells, miR-210, miR-29a (all P<0.001) and miR-125b (P<0.01–0.0001) were significantly upregulated by EGCG. In SiHa cells, miR-125b (both P<0.001) and miR-203 (P<0.01 and <0.0001) were significantly upregulated by EGCG. In conclusion, the results of the present study suggest that EGCG suppresses cervical carcinoma cell growth, possibly via regulating the expression of miRs, suggesting their potential as therapeutic targets for the control and prevention of cervical cancer. Additionally, EGCG may be considered a novel anti-cervical cancer drug in the future. [ABSTRACT FROM AUTHOR]

The objective of the present study was to investigate differences in the expression of apoptosis-related factors in the eutopic and ectopic endometrium (EuE/EE) in women with adenomyosis before and after laparoscopic bilateral uterine artery occlusion (LUAO). Ten patients with uterine adenomyosis who received LUAO were selected as the research subjects, from whom EuE and EE tissues were obtained before and after LUAO and detected for the expression of apoptosis-related molecules in EuE and EE by PT-PCR and Western blot, and changes in the mitochondrial structure by electron microscopy. Normal endometrial stromal cells (NESC), and EuE/EE stromal cells in women with adenomyosis were cultured in a 1% O2, 5% CO2 incubator to establish a physical anoxia state in an in vitro stromal cell model. The expression of apoptosis-related molecules was observed at 0, 6, 12, 24 and 48h of hypoxic. The results showed that the expression of apoptosis-related factors in EuE and EE were increased significantly after LUAO and under hypoxic conditions in vitro, suggesting that transient ischemia and hypoxia were involved in the apoptosis of adenomysis lesions, and that uterine artery occlusion could remove adenomyosis lesions on tissue/cell level by cytoreduction, thus reaching the goal of treating adenomyosis effectively. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To assess the long-term efficacy and quality of life associated with laparoscopic bilateral uterine artery occlusion plus partial resection of symptomatic adenomyosis. Study design: A total of 182 eligible patients with symptomatic adenomyosis were treated by laparoscopic bilateral uterine artery occlusion plus partial resection of adenomyosis from July 2003 to July 2009. Menstrual blood loss was measured using a pictorial blood loss assessment chart. Pain intensity during menstruation was evaluated on a 10-point visual analog scale (VAS). Health-related quality of life was measured using the WHOQOL-BREF. Results: A total of 179 patients with 3 years follow-up were enrolled in this retrospective study. No severe complications were noted during the surgical procedure or follow-up period. The mean postoperative dysmenorrhea and menorrhagia scores were significantly improved (all p <0.01) at 3, 12 and 36 months postoperatively, compared with preoperative scores. The volume of the uterus was continuously reduced at 3, 6, 12 and 36 months postoperatively, and had shrunk by 58.3% at 36 months after surgery, compared with the preoperative volume. Notably, only 1.7% (3/179) of patients had received a hysterectomy at 36 months follow-up. In addition, patient's health-related quality of life scores were significantly increased (p <0.01) compared with preoperative scores. Conclusion: Laparoscopic bilateral uterine artery occlusion plus partial resection of symptomatic adenomyosis is effective. There was a very low recurrence rate detected by ultrasound at 36 months. [Copyright &y& Elsevier]

Highlights This study introduces an innovative technique for the fabrication of copper‐based polytetrafluoroethylene (PTFE)/graphite self‐lubricating composites. By harnessing the exceptional capabilities of selective laser sintering (SLS), we efficiently create three‐dimensional, continuous, and porous graphite preforms. Following this, the composite is formed through a combination of electroplating and vacuum extrusion methods. Subsequently, PTFE was vacuum impregnated into the microporous structure of the graphite preforms, and the composites were obtained through freeze‐drying, plasticizing, and machining processes. The resulting copper‐based PTFE/graphite self‐lubricating composites exhibit an exceptional blend of properties. Notably, there is a significant reduction in the average coefficient of friction, dropping from 0.14 to 0.02, and a marked decrease in the wear rate, from 1.358 × 10−5 to 1.109 × 10−5 mm3/N·m, as compared to graphite as a standalone lubricant. This represents a substantial improvement in performance, underscoring the effectiveness of the proposed fabrication method. The porous graphite with controllable shape distribution was prepared. Surface copper plating improves surface bonding. Controllable copper matrix composites with double lubricant were prepared. The average friction coefficient is as low as 0.02. [ABSTRACT FROM AUTHOR]

Temperature plays a critical role in wheat grain development. A controlled phytotron glasshouse study was done to investigate the effects of short-term low or high temperature stress on grain yield and the proportions of starch and protein in two wheat cultivars Ningmai 13 and Zhenmai 12. The duration of grain filling was longer under low temperature stress and was shorter under high temperature stress during various stages of grain filling. Grain filling rate, grain width, grain yield, contents of total starch and amylopectin of both cultivars were decreased by low or high temperature stress. However, the proportions of total protein, gliadin, and glutenin were increased dramatically after abnormal temperature stress. The significant increase in the proportion of protein was mainly caused by higher proportions of ω-gliadin and HMW-GS. For both cultivars, the formation of starch, protein, and grain yield was most sensitive to temperature stress during 15–17 days post anthesis (DPA), followed by 7–9 DPA for grain starch and yield formation, and 23–25 DPA for grain protein formation, respectively. Our study suggested that both high and low temperature stress after anthesis affected winter wheat grain yield, starch and protein accumulation, especially during the period of 15–17 DPA. [Display omitted] • Low or high temperature stress decreased wheat grain width and grain-filling rate, resulting in a huge yield loss. • The abnormal temperature decreased the starch content, while dramatically increased ω-gliadin and HMW-GS in grains. • The most sensitive stage of wheat yield and grain main components to short-term temperature stress was 15–17 DPA. [ABSTRACT FROM AUTHOR]