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An arc is constructed at the end of the planetary wheel profile shaft of the planetary traction drive, and the contact point between the arc and the outer ring and the end face of the solar wheel shaft is kept on the radial traction contact line. A new type of a more compact bearing reducer is designed by replacing thrust bearings cleverly. In this study, the radial contact stress and flange stress of the contact line are analyzed based on the assembly interference, the full arc element line modification and the influence of the contact line edge chamfering. Several sets of 3D ideal models are established and analyzed by Abaqus software. The results show that the edge stress concentration exists in the contact lines of the outer ring, planetary wheel and solar wheel of the bearing reducer. Reasonable contact-element trimming and edge chamfering can make contact stress uniform and improve edge effect. The best way to improve the contact stress of traction drives is to modify the contact element and chamfering the edge simultaneously. The distribution and size of the contact stress at the flange are basically the same under different convexity modification, and the axial and radial contacts between the contact line of the planet wheel and the outer ring and the contact line of the sun wheel and the flange can remain on a traction line.

Animal studies on vascular aging pose a few limitations. One of the most important reasons for this is the absence of a fast and efficient model of vascular tissue aging. In this study, ex vivo aortic culture and Matrigel subcutaneous implantation are combined to develop a new model for studying vascular cellular senescence. Eight‐week‐old C57BL/6J mice are used to obtain aortas. Bleomycin is used to induce aortas senescence in vitro. Then, aortas are transplanted to the acceptor mice with Matrigel. Senescence is evaluated using western blotting, quantitative polymerase chain reaction, and senescence‐associated beta‐galactosidase activity. Inflammatory cytokines are detected using Luminex Liquid Suspension Chip. RNA levels are analyzed by transcriptome sequencing. The results revealed that vessels in the bleomycin group exhibited significant senescence than those in the control group that can be enhanced by stripping vessel adventitia. The levels of cytokines such as interleukin (IL‐2, IL‐1β, and IL‐6 increased significantly in the ex vivo model. Furthermore, transcriptome sequencing revealed 56 significantly differentially expressed genes (DEGs) in ex vivo model vessels compared with those in naturally aging aortas. In conclusion, this study introduces a cost‐effective and time‐saving vessel senescence model for vascular cellular senescence. [ABSTRACT FROM AUTHOR]

With the rapid development of the 3D printing technique, the concept of 4D has emerged, defining time as the fourth dimension. This concept allows for changes in the appearance, function, or other properties of 3D printed objects in response to certain controlled external stimuli over time. In this work, a new photocomposite containing fluorescein based is designed on an interpenetrating polymer network (IPN) system, this system can be generated by the simultaneous photopolymerization of acrylate and epoxide monomers under visible LED@405 nm irradiation. Unexpectedly, combining the reversible fluorometric turn‐on property of fluorescein and the deformation of the IPN in the presence of water, the 3D flower structure printed from this photocomposite would demonstrate a novel dual responsive behavior with both fluorescence and shape changes when it is exposed to water for a short time. This work would present a novel functional photocomposite material and also expand the application prospect of 4D printing. [ABSTRACT FROM AUTHOR]

The vehicle detection algorithm based on visual perception has been applied in all types of automatic driving scenes. However, there are still flaws in the current detection algorithm model, especially for small objects. The detection effect of vehicle objects with small pixels in the image is often missed and wrongly detected. This research proposes an improved feature fusion module based on double‐channel residual pyramid (DRP) structure for autonomous detection algorithm which named binary residual feature pyramid network (BiResFPN) to solve the above problems. Firstly, a DRP structure, which can effectively supplement the shallow information of the network, is proposed. The residual structure is added to the output feature map for further supplement. Then, an average sampling method of positive and negative samples based on intersection‐over‐union (IOU) value is proposed on the basis of this structure, aimed at the unbalanced sampling of positive and negative samples in the training stage of faster regions with CNN features (RCNN). It leads to the reduction of the interference of a large number of simple negative samples, which makes the learned model better. The experimental results based on the KITTI and BDD100K dataset datasets show that the capability of the feature fusion module based on DRP structure is strong for small object detection. Compared with Faster‐RCNN (FPN), the detection algorithm of small object detection accuracy APsmall was increased by 2.6%, APmedium and APlarge was increased by 1.1% and 0.3%. [ABSTRACT FROM AUTHOR]

Objective: To prepare freeze-dried long-circulation oridonin liposomes with optimized parameters., Methods: Ethanol injection method followed by freeze-drying was used to prepare the liposomes. Sephadex column was used to purify liposomes. Effects of formulation factors on entrapment efficiency of long-circulation oridonin liposomes were studied. The particle size, distribution and in vitro release were determined. Pharmacokinetics of oridonin liposomes in rats was determined by HPLC and the pharmacokinetic parameters calculated by Kinetica(TM) software were compared with conventional oridonin liposomes and solution., Results: The optimized lipid formulation for long-circulation liposomes was composed of soy lecithin, cholesterol and DSPE-PEG 2000 with a ratio of 1:0.5:1.8(w/w). The ratio of drug to lipid was 1:6. Freeze-drying protectant was a mixture of glucose and mannitol (3:1). The entrapment efficiency (EE) of long-circulation oridonin liposomes was about 65%. The particle size of liposomes after hydrolyzation was 164 nm with good DPI. The liposomes showed a sustained drug release in vitro. Intravenous injected oridonin fitted with two-compartment pharmacokinetic model. The MRT of long-circulation liposomes was 2 times and 6 times and AUC was about 2 times and 3 times of conventional liposomes and oridonin solution, respectively., Conclusion: Freeze-dried liposomes with high EE have been obtained by the proposed approach. This long-circulation liposomes extend oridonin half time and significantly increase AUC in rats.