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Aiming at the problem of low detection accuracy of occluded pedestrian in traffic environments, this paper proposes a key points and visible part fusion network for occluded pedestrian detection. The proposed algorithm constructs two attention modules by introducing human key points and the bounding box of visible parts respectively, which suppresses the occluded parts in the channel features and spatial features of pedestrian features respectively. Experimental results on CityPersons and Caltech datasets demonstrate the effectiveness of the proposed algorithm. The missing rate (MR) is reduced to 40.78 on the Heavy subset of the CityPersons dataset and surpasses many outstanding methods. [ABSTRACT FROM AUTHOR]

Within the fields of underwater robotics and ocean information processing, computer vision-based underwater target detection is an important area of research. Underwater target detection is made more difficult by a number of problems with underwater imagery, such as low contrast, color distortion, fuzzy texture features, and noise interference, which are caused by the limitations of the unique underwater imaging environment. In order to solve the above challenges, this paper proposes a multi-color space residual you only look once (MCR-YOLO) model for underwater target detection. First, the RGB image is converted into YCbCr space, and the brightness channel Y is used to extract the non-color features of color-biased images based on improved ResNet50. Then, the output features of three scales are combined between adjacent scales to exchange information. At the same time, the image features integrated with low-frequency information are obtained via the low-frequency feature extraction branch and the three-channel RGB image, and the features from the three scales of the two branches are fused at the corresponding scales. Finally, multi-scale fusion and target detection are accomplished utilizing the path aggregation network (PANet) framework. Experiments on relevant datasets demonstrate that the method can improve feature extraction of critical targets in underwater environments and achieve good detection accuracy. [ABSTRACT FROM AUTHOR]

It is significant to predict welding quality during gas metal arc welding process. The welding defect detection algorithm has been developed based on convolutional neural network (CNN). The sensing system and image processing algorithm for molten pools has been developed. It overcomes the interference caused by the arc light to obtain clear images of the molten pool's boundaries. The molten pools images are used to build up training set and test set for training and testing the CNN model. The model is designed to extract the visual features of molten pool images to predict the penetration state, the welding crater, and slags. Through optimizing the network parameters such as kernel-size, batch-size and learning rate, the prediction accuracy is higher than 95%. Moreover, the model enhances additional focus on the welding crater based on the welder experience. The mechanisms between molten pool characteristics and welding defects were analyzed based on the welder experience and the visual features of the model. It is found that the model judges the occurrence of burn-through with the black hole in the middle zone of the molten pool. When the surface pores are generated, the model exhibits a strong response to circular voids in the semi-solid region at the trailing end of the molten pool. The size and shape of fusion holes exhibit a strong correlation with the molten state. When the shape of the crater does not appear concave, it often signifies excessive penetration. It contributes to enhancing the algorithm's robustness during various welding scenarios. [ABSTRACT FROM AUTHOR]

The evolution of excitons from 2D to 3D is of great importance in photo-physics, yet the layer-dependent exciton polarizability hasn't been investigated in 2D semiconductors. Here, we determine the exciton polarizabilities for 3- to 11-layer black phosphorus—a direct bandgap semiconductor regardless of the thickness—through frequency-resolved photocurrent measurements on dual-gate devices and unveil the carrier screening effect in relatively thicker samples. By taking advantage of the broadband photocurrent spectra, we are also able to reveal the exciton response for higher-index subbands under the gate electrical field. Surprisingly, dark excitons are brightened with intensity even stronger than the allowed transitions above certain electrical field. Our study not only sheds light on the exciton evolution with sample thickness, but also paves a way for optoelectronic applications of few-layer BP in modulators, tunable photodetectors, emitters and lasers. Here, the authors determine the exciton polarizabilities for 3- to 11-layer black phosphorus via frequency-resolved photocurrent measurements on dual-gate devices, and unveil the exciton response for higher-index sub-bands under the gate electrical field, as well as a carrier screening effect in thicker samples. [ABSTRACT FROM AUTHOR]

Objective: Hydrocephalus is one of the most significant comorbidities of pediatric suprasellar tumors. Up to 37.5–68.0% of patients were diagnosed with hydrocephalus at admission. However, after surgical resection of the tumor, 9.3–51.4% of the hydrocephalus will persist and require a ventriculoperitoneal shunt (VPS) surgery. The purpose of this study was to identify the risk factors associated with postresection shunting in children with suprasellar tumors. Methods: We conducted a retrospective analysis of children who underwent surgery for suprasellar tumors at our department from February 2011 to December 2020. We used univariate and multivariate analysis to screen the factors that might be correlated with postoperative shunt placement, taking into account patients' characteristics, tumor histology/size/calcification, the severity of preoperative hydrocephalus, the involvement of ventricles, external ventricular drainage (EVD) placement, postoperative intraventricular hematoma, the extent of resection, and other surgical details. Results: A total of 124 children who underwent surgery for suprasellar tumors were included in our study. Hydrocephalus was present in 55 patients (44.3%) at admission; 23 patients (18.5%) received VPS implantation after tumor removal. Univariate analysis showed that the involvement of ventricles (p = 0.002), moderate/severe preoperative hydrocephalus (p = 0.001), postoperative intraventricular hematoma (p = 0.005), and EVD implantation (p = 0.001) were significantly associated with postoperative VPS. Multivariate analysis confirmed that only ventricle involvement (p = 0.002; OR = 5.6; 95%CI 1.8–17.2) and intraventricular hematoma (p = 0.01; OR = 10.7; 95%CI 1.8–64.2) were independent risk factors for postresection shunting. Conclusion: Ventricle involvement and intraventricular hematoma can be identified as independent predictors for postoperative shunting in pediatric suprasellar tumors. [ABSTRACT FROM AUTHOR]

Coordinated Behavioral Care's (CBC) Pathway Home™ (PH) program partnered with Wellth, Inc., a mobile health platform grounded in behavioral economics theory, to help individuals with behavioral health conditions build and reinforce health habits by providing daily reminders to take medication, requiring tasks (photos demonstrating remembrance), and providing financial incentives tied to behaviors. CBC made Wellth, Inc. available to individuals enrolling in its PH program for the purpose of demonstrating the feasibility of implementing a novel mobile technology grounded in behavioral economic theory to increase habits of health activities, such as taking medication, among adults with behavioral health conditions. [ABSTRACT FROM AUTHOR]

The C-terminally truncated Y145Stop variant of prion protein (PrP23-144) has been linked to a heritable prionopathy in humans and is also capable of triggering a transmissible prion disease in mice. PrP23-144 can be converted from soluble monomeric form to amyloid under physiological conditions, providing an in vitro model for investigating the molecular basis of amyloid strains and cross-seeding barriers. Here, we use magic-angle spinning solid-state NMR to establish the sequential backbone and sidechain 13C and 15N chemical shift assignments for amyloid fibrils formed by the A117V and M129V mutants of human PrP23-144, which in the context of full length PrP in vivo are among the specific residues associated with development of Gerstmann–Straüssler–Scheinker disease. The chemical shift data are utilized to identify amino acids comprising the rigid amyloid core regions and to predict the protein secondary structures for human PrP23-144 A117V and M129V fibrils. [ABSTRACT FROM AUTHOR]

The undesirable effects of silver nanoparticles (AgNPs) on soil environment have caused much concern. The previous studies, however, focused on sandy soil, with little known on others. In present study, the effects of polyvinylpyrrolidone-coated AgNPs (0, 1, 10, and 100 mg kg− 1 soil) on enzyme activities (urease and dehydrogenase), ammonia-oxidizing bacteria (AOB) and archaea (AOA), bacterial and archaeal communities, and microbial function profile in a yellow-brown loam soil were investigated. The significant dose-response inhibitions of AgNPs on enzyme activities were observed, with dehydrogenase more susceptible to AgNPs. Both of bacterial and archaeal amoA genes were reduced by AgNPs above 10 mg kg− 1, with AOB more susceptible to AgNPs than AOA. AgNPs at 100 mg kg− 1 caused reductions on the dominant Nitrosospira and Nitrosomonas, and even disappearance on Nitrosovibrio, while increase on Nitrososphaera significantly. AgNPs also changed bacterial and archaeal community structure. Exposure to AgNPs at 100 mg kg− 1 caused significant increases by 186.79% and 44.89% for Bacteroidetes and Proteobacteria, while decreases by 47.82%, 44.09%, 43.67%, and 80.44% for Actinobacteria, Chloroflexi, Planctomycetes, and Verrucomicrobia, respectively. Moreover, three dominant archaeal phyla (Thaumarchaeota, Euryarchaeota, and Parvarchaeota) were also reduced in the presence of AgNPs, especially Thaumarchaeota with the significant reduction of 13.71%. PICRUSt prediction revealed that AgNPs indeed had the potential to change soil microbial community's functional contributions. It must be cautious on the interference of AgNPs to soil ecological functions in the future. [ABSTRACT FROM AUTHOR]