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The aluminum alloy performance gradient plate was prepared by friction stir joining. Analysis results of the macro morphology, microstructure, and hardness of the aluminum alloy performance gradient plate prepared under various parameters show that when the feed speed of the stirring tool is 250 mm/min, the downward pressure of the stirring tool is 6.6 mm, and the rotation speed of the stirring tool changes from 200 rpm to 800 rpm. The macroscopic morphology of the aluminum alloy gradient plates prepared by the method first changed from burr to smooth, and vice versa. There is a different cross-section morphology of the prepared aluminum alloy gradient plates, however, the aluminum alloy plates are stirred and involved with each other, and the grains of the prepared plates are refined. The hardness of the upper and lower surfaces of the aluminum alloy gradient sheet decreases, whereas that of the upper surface of the side increases, and that of the middle and bottom sides also decreases. However, the hardness of the middle side of the sheet prepared with the rotation speed of the stirring tool at 800 rpm increases, but that of the bottom side still decreases. Obtained through analysis that the performance of the aluminum alloy gradient sheet prepared at the stirring tool rotation speed of 500 rpm increases in equal proportion to achieve a good performance gradient change.

Salient object detection aims to identify the most prominent objects within an image. With the advent of fully convolutional networks (FCNs), deep learning-based saliency detection models have increasingly leveraged FCNs for pixel-level saliency prediction. However, many existing algorithms face challenges in accurately delineating target boundaries, primarily due to insufficient utilization of edge information. To address this issue, we propose a novel approach to improve the boundary accuracy of salient target detection by integrating salient target and edge information. Our approach comprises two key components: a Self-attentive Group Pixel Fusion module (SGPFM) and a Bidirectional Feature Fusion module (BFF). The SGPFM extracts salient edge features from the lower layers of ResNet50 and salient target features from the higher layers. These features are then optimized using a self-attentive mechanism. The BFF module progressively fuses the salient target and edge features, optimizing them based on their logical relationships and enhancing the complementarities among the features. By combining detailed edge information and positional target information, our method significantly enhances the detection accuracy of target boundaries. Experimental results demonstrate that the proposed model outperforms the latest existing methods across four benchmark datasets, providing accurate and detail-rich salient target predictions. This advancement marks a significant contribution to the development of the field. [ABSTRACT FROM AUTHOR]

Three types of pinless friction stir spot welding (PFSSW) tools were designed employing Fibonacci spiral curve, involute curve, and Archimedean spiral curve to create corresponding grooves. Subsequently, PFSSW experiments were conducted on copper sheets using these three distinct tools. The surface morphology, cross-sectional macrostructure and microstructure, microhardness, joint strength, fracture type, and fracture surface morphology of the joints were analyzed under the influence of different tools. The research findings indicate that the Fibonacci spiral curve groove (FSCG) tool exhibits the highest disparity in three-dimensional morphology within the central zone of the joint, followed by the involute curve groove (ICG) tool and the Archimedean spiral curve groove (ASCG) tool. The ICG tool generates the widest stirring zone (SZ) in the joint, while the FSCG tool produces the deepest SZ. The grains of SZ under all three tools is coarser compared to the base material. The microhardness values under the ASCG tool are relatively higher, whereas those under the FSCG tool are lower. Among the welded specimens, those created using the FSCG tool exhibit the highest average tensile-shear failure load of 8.21 kN, followed by the ICG tool of 7.80 kN, and the ASCG tool yielding the lowest average tensile-shear failure load of 7.77 kN. The fracture type of the specimens welded by FSCG tool is semi-nugget pull-out fracture, while the joint specimens of ICG tool and ASCG tool are both nugget pull-out fracture. The fracture mode of the joints under all three tools is characterized as ductile fracture. The conducted research can not only enrich the variety of PFSSW tool grooves, but also enhance the comprehension of joint properties under distinct tool groove configurations. [ABSTRACT FROM AUTHOR]

The friction stir welding (FSW) of 6010-T6 aluminum alloy sheet with 10 mm thickness was carried out with tool tilt angle of 0°. The process parameters that could realize effective joint were given. The performance of the weld zone was tested. The experimental results showed that the effective FSW could be achieved under the process parameters of rotation speed of 400–600 rpm and welding speed of 200–400 mm/min. The tensile strength of the weld zone was the best under the rotation speed of 600 rpm and welding speed of 400 mm/min, which was 86.4% of the base metal, under which process the microhardness of the nugget zone was higher than that under other processes, and the grain was significantly finer than that of the base metal zone. This paper presents the technological breakthrough of the FSW of 10 mm thickness aluminum alloy with tool tilt angle of 0°. [ABSTRACT FROM AUTHOR]

Welding of 10 mm thick AZ31B magnesium alloy by stir friction welding technique. The effects of process parameters on the microstructure, tensile strength and impact resistance of the joints were analyzed. The results showed that the joints were formed with good quality and no obvious defects, and the joints were fine-grained and accompanied by grain dislocations. The grain dislocation in the hot machine influence zone is more obvious there is a dense grain dislocation zone, and the distribution is not uniform. When the spindle speed is 800 and 1000 rpm, respectively, the best impact resistance of the welded joint impact work is 8.02 J, which is about 94.2% of the impact resistance of AZ31B magnesium alloy base material. When the spindle speed is 1000r/min and the welding speed is 150 mm/min, the tensile strength of the welded joint is the largest, reaching 85.8% of the base material and the post-break elongation is 1.9 times that of the base material. Thick plate magnesium alloy plate welded joints overall performance is not uniform, welded plate bottom mechanical properties of the worst, weld core area doped magnesium alloy oxide, joint tensile fracture crack source from the bottom of the plate to the weld surface expansion. [ABSTRACT FROM AUTHOR]

ObjectiveTo explore the effect of paliperidone palmitate treatment on schizophrenic patients in the community.Methods446 schizophrenic patients who used paliperidone palmitate injection were selected in Shanghai. Before and after the treatment， the disease family burden scale， the concise evaluation scale of drug treatment compliance， the VAS100 score of treatment satisfaction， the short form of quality of life measurement scale， and the screening scale of social function defects were used to evaluate the effects of paliperidone palmitate injection. The data were statistically analyzed using SPSS 26.0 software.ResultsAfter using paliperidone palmitate injection， the total score of family burden （13.94±12.17）， the score of daily family activities （3.26±2.74）， the score of family entertainment activities （2.21±2.30）， and the score of family relationship （2.79±2.76） were significantly higher than those before the treatment （14.98±12.64， 3.51±2.88， 2.48±2.38， 3.11±2.87， respectively， all with P

Objective To explore the changes in root volume and root resorption in incisor arteries from adult patients with skeletal class Ⅲ malocclusion before and after camouflaged orthodontic treatment and to provide a reference for the clinic. Methods Thirty permanent dentition adult patients with skeletal class Ⅲ malocclusion were included from the Orthodontic Department. CBCT data of each patient at pretreatment and posttreatment were acquired, and 3D digital root models were reconstructed. The whole and segmented root volumes (cervical part, bodily part and apical part) of the right incisors were calculated. Results The root volumes (whole, cervical part, bodily part and apical part) posttreatment were smaller than those pretreatment (P0.05). Mandibular central incisors and lateral incisors showed more root resorption in the apical root than in the cervical root and bodily root (P0.05). The absorption ratio showed a significant difference in the mandibular lateral incisors (P = 0.028). Conclusion After camouflaged orthodontic treatment of adult skeletal class Ⅲ malocclusion, incisor root resorption occurred mainly in the apical part, but the cervical and bodily parts should also be considered. There was a high risk of root resorption in the mandibular incisors.