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Remaining useful life (RUL) prediction of rolling bearings is of paramount importance to various industrial applications. Recently, intelligent data-driven RUL prediction methods have achieved fruitful results. However, the existing methods heavily rely on the quality and quantity of the available data. For some critical bearings in industrial scenarios, the real run-to-failure data are insufficient, which impair the applicability of data-based methods for industrial practices. To address these issues, this article proposes a novel dynamic model-assisted RUL prediction approach for rolling bearing, in which sufficient simulation data are applied as the training data to solve the problem caused by insufficient real data. More specifically, a dynamic rolling bearing model is introduced for simulating the degradation process of physical structures. Then, a multilayer cross-domain transformer network is developed to implement RUL prediction and adapt the learned prediction knowledge from simulation to the actual measurements. Furthermore, a mutual information loss is utilized to preserve the generalized prediction knowledge of the measured data. The proposed approach can achieve a high RUL prediction accuracy with only limited measured data, which tackles the drawbacks of the existing data-driven methods. The experimental results of the rolling bearing degradation datasets demonstrate the effectiveness and superiority of the proposed RUL prediction approach.

Target detection and tracking represent key challenges facing miniature fixed-wing unmanned aerial vehicles (UAVs), particularly at high cruising speeds. Therefore, this paper proposes a vision-based target detection and tracking algorithm that systematically couples two mainstream methods, namely, you only look once (YOLO) and kernel correlation filter (KCF) algorithms. This combination enables small fixed-wing UAVs to achieve reliable target detection and rapid target tracking. A customized vision-guidance module is constructed to implement this algorithm, and a dual-thread execution mechanism is developed to ensure that the computational resources are used effectively. A miniature fixed-wing UAV experimental platform is also constructed and evaluated. Flight experiments are performed, and the results demonstrate that the developed algorithm can achieve satisfactory detection and tracking accuracy for stationary and moving ground targets in complex environments.

Two new genera of euophryine jumping spiders in the Laufeia group are established for species from Southeast Asia: Amoenema Yu & Zhang, gen. nov. and Lokina Yu, Maddison & Zhang, gen. nov., with descriptions of 12 new species: Amoenema erhai Yu & Zhang, sp. nov. (♂♀, type species), A. liuae Yu & Zhang, sp. nov. (♂♀), A. zizhongi Yu & Zhang, sp. nov. (♂♀), Lokina blombergi Yu, Maddison & Zhang, sp. nov. (♂♀), L. chiyou Yu & Zhang, sp. nov. (♂♀, type species), L. fuxi Yu & Zhang, sp. nov. (♂♀), L. kubah Yu, Maddison & Zhang, sp. nov. (♂), L. nyuewa Yu & Zhang, sp. nov. (♂♀), L. pixi Yu, Maddison & Zhang, sp. nov. (♂), L. tamasi Yu & Zhang, sp. nov. (♂♀), L. wuyi Yu & Zhang, sp. nov. (♂), L. zhishengi Yu & Zhang, sp. nov. (♂). In addition, three new combinations are proposed: Amoenema robusta (Lei & Peng, 2012) comb. nov. (transferred from Euophrys C. L. Koch, 1834), Lokina eximia (Zhang & Maddison, 2012) comb. nov. (transferred from Laufeia Simon, 1889) and L. tengchongensis (Lei & Peng, 2012) comb. nov. (transferred from Chalcovietnamicus Marusik, 1991).

Cu-based electrocatalysts for the valorization of furans are comprehensively reviewed, which elucidates the working mechanism and provides guidance for catalyst design in the electrochemical refining of biomass feedstock.

We demonstrate a novel way for powdered hemostats to enter deep bleeding sites of complicated wounds and achieve targeted hemostasis.

Background: Dual Specificity Phosphatase 3 (DUSP3) regulates the innate immune response and is associated with ischemia/reperfusion (I/R). However, the precise function of DUSP3 in acute myocardial infarction (AMI) remains to be established. Methods: In this study, the AMI model in vivo was established in mice by permanent left anterior descending coronary artery (LAD) occlusion, and primary neonatal mouse cardiomyocytes were treated with hypoxia for 12 hours to mimic AMI in vitro. Sh-DUSP3 and AAV9-sh-DUSP3 were used to knock down the DUSP3 expression. LVEF%, LVFS%, SOD1, and HO-1 level, and TTC staining were used to test the cardiac function. Flow cytometric analysis, Western blot, and TUNEL staining were used to investigate the effect of DUSP3 knockdown on apoptosis. Moreover, we detect inflammatory factors expression and oxidative stress by ELISA. Besides, we investigate DUSP3 expression by RT-qPCR. Results: Our findings determined the role of DUSP3 in the progression of AMI. And demonstrated that DUSP3 knockdown alleviated oxidative stress, inflammation, and apoptosis. In addition, our results indicated that DUSP3 knockdown could regulate the expression of p-NF-κB, ICAM1, and VCAM1. Conclusion: Our results demonstrated that the knockdown of DUSP3 could effectively alleviate AMI symptoms and be mediated through the NF-κB signaling pathway.

We develop a design method for a pattern-free absorber driven by superposed Fabry–Perot resonances, which can achieve an average absorption of 96% in the solar irradiation band.

The development of medical device technology has led to the rapid growth of medical imaging data. The reconstruction from two-dimensional images to three-dimensional volume visualization not only shows the location and shape of lesions from multiple views but also provides intuitive simulation for surgical treatment. However, the three-dimensional reconstruction process requires the high performance execution of image data acquisition and reconstruction algorithms, which limits the application to equipments with limited resources. Therefore, it is difficult to apply on many online scenarios, and mobile devices cannot meet high-performance hardware and software requirements. This paper proposes an online medical image rendering and real-time three-dimensional (3D) visualization method based on Web Graphics Library (WebGL). This method is based on a four-tier client-server architecture and uses the method of medical image data synchronization to reconstruct at both sides of the client and the server. The reconstruction method is designed to achieve the dual requirements of reconstruction speed and quality. The real-time 3D reconstruction visualization of large-scale medical images is tested in real environments. During the interaction with the reconstruction model, users can obtain the reconstructed results in real-time and observe and analyze it from all angles. The proposed four-tier client-server architecture will provide instant visual feedback and interactive information for many medical practitioners in collaborative therapy and tele-medicine applications. The experiments also show that the method of online 3D image reconstruction is applied in clinical practice on large scale image data while maintaining high reconstruction speed and quality.

BACKGROUND: The treatment of sacral fractures accompanied by nerve injury is complex and often leads to an unsatisfactory prognosis and poor quality of life in patients. OBJECTIVE: The present study aimed to investigate the clinical value of using 3.0T magnetic resonance contrast-enhanced three-dimensional (MR CE-3D) nerve view magnetic resonance neurography (MRN) in the diagnosis and management of a sacral fracture accompanied by a sacral plexus injury. METHODS: Thirty-two patients with a sacral fracture accompanied by a sacral plexus injury, including 24 cases of Denis spinal trauma type II and 8 cases of type III, were enrolled in the study. All patients had symptoms or signs of lumbosacral nerve injury, and an MRN examination was performed to clarify the location and severity of the sacral nerve injury. Segmental localization of the sacral plexus was done to indicate the site of the injury as being intra-spinal (IS), intra-foraminal (IF), or extra-foraminal (EF), and the severity of the nerve injury was determined as being mild, moderate, or severe. Surgical nerve exploration was then conducted in six patients with severe nerve injury. The location and severity of the nerve injury were recorded using intra-operative direct vision, and the results were statistically compared with the MRN examination results. RESULTS: MRN showed that 81 segments had mild sacral plexus injuries (8 segments of IS, 20 segments of IF, 53 segments of EF), 78 segments had moderate sacral plexus injuries (8 segments of IS, 37 segments of IF, and 33 segments of EF), and 19 segments had severe sacral plexus injuries (7 segments of IS, 9 segments of IF, and 3 segments of EF). The six patients who underwent surgery had the following intra-operative direct vision results: 3 segments of moderate injury (IF) and 20 segments of severe injury (7 segments of IS, 10 segments of IF, 3 segments of EF). There was no statistically significant difference in the results between the intra-operative direct vision and those of the MRN examination (p> 0.05). CONCLUSION: MR CE-3D nerve view can clearly and accurately demonstrate the location and severity of sacral nerve injury accompanied by a sacral fracture, and has the potential for being the first choice of examination method for this kind of injury, which would be of important clinical value.

With the explosive growth of distributed renewable energy connected to the power system, the application of AC–DC hybrid distribution network with power electronic transformer (PET) becomes more and more extensive. An equivalent loss model is formulated from the perspective of the internal topology of PET. Then, a novel PET power flow model is established to obtain the relationship between the three ports. On this basis, reactive power of PV nodes connecting PET and distributed renewable generation is modified by establishing an equivalent impedance matrix, thus the forward–backward sweep load flow calculation method is improved for power flow calculation and volt/var control of distribution network. Different from traditional reactive optimization methods, a multi-objective reactive power optimization model considering the PET and two types of photovoltaic converters is established in this paper, with the targets of minimizing voltage deviation and power loss simultaneously. Finally, the numerical simulation shows the accuracy, rationality, and feasibility of the proposed method.

Purpose This study aims to investigate how credit rating agencies and banks, important credit market participants, incorporate corporate social responsibility (CSR)-related information in their assessment of firm’s creditworthiness. Design/methodology/approach The authors collect stand-alone CSR reports published by Fortune 500 companies from 2002 to 2014 and use file size as a readability measure to investigate the impact of stand-alone CSR reports’ readability on firms’ credit ratings and cost of borrowing. Findings The authors find that firms with higher CSR report readability enjoy higher credit ratings and lower costs of bank loans, suggesting that rating agencies and banks perceive lower default risk for firms with more readable CSR reports. Further analysis indicates that the positive association between CSR report readability and credit ratings is more pronounced for firms with high CSR performance. Conversely, the negative association between CSR report readability and bank loan spreads is more pronounced for firms with low CSR performance and credit quality, suggesting complementary roles of rating agencies and banks in their use of CSR reports. Originality/value Overall, the results highlight the importance of improving the textual characteristics of CSR reports, especially readability, in reducing information risk in the credit market.

Organic pollutants (OPs) have garnered a considerable amount of attention in recent times due to their extreme toxicity toward humans and the ecosystem. The need for an inexpensive yet robust, sensitive, selective, and easy-to-operate method for detecting OPs remains a challenge. Herein, a portable electrochemical sensor is proposed based on manganese porphyrin-functionalized carbon cloth (CC). To explain the electrochemical performance of the sensor, cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were employed. The presence of manganese(III) ion in the center of the porphyrin ligand acted as an agent for the transfer of electrons and enhanced sensitivity toward analyte-specific redox catalysis. Moreover, it allowed for the concurrent detection of multiple analytes in a complex environment. The modified CC electrode can selectively detect nitroaromatic and phenolic compounds with accessible data collected through wireless means onto a smartphone device. The as-synthesized electrode demonstrated a higher sensitivity toward the detection of nitrobenzene (NB) and aqueous phenol with a limit of detection (LOD) found to be 5.9268 × 10

In this study, a test beam model of negative moment region was designed to study its deflection characteristics under over-limit static load and variable amplitude cyclic load scenarios. (1) According to the deflection test results of the test beam under over-limit static load, the load-deflection curve under static load before and after 10000 times of over-limit fatigue load tended to sharply increase in the first place and then slow down afterwards. At the ultimate load, the maximum deflection value of the two was 8.625 mm and 8.76 mm, respectively. The maximum deflection value after 10000 times of over-limit fatigue load increased by 1.57% compared with that before. (2) The deflection test results of the test beam under variable amplitude cyclic load showed that both the total deflection and the residual deflection percentage increased firstly and decreased with the increasing fatigue load times. The total deflection ranged from 4.07–4.3 mm, and the residual deflection percentage was 0.1–1.65%; The residual deflection percentage reached a maximum of 1.65% when the fatigue load times reached 2 million. (3) The deflection test results of the test beam under over-limit variable amplitude fatigue load showed that the maximum residual deflection reached 0.08 mm (maximum residual deflection percentage 1.75%), 0.11 mm (maximum residual deflection percentage 2.30%), 0.16 mm (maximum residual deflection percentage 2.65%) after 1.5, 2 and 3 times over-limit variable amplitude fatigue load was imposed respectively. The maximum deflection did not fluctuate obviously, indicating that the test beam was had sound working performance. (4) In this study, the shear stiffness and fatigue load times were fully considered, the mean value of the ratio of the deformation value to the measured value of the test beam was 0.89, and the standard deviation was 4.86%. When the fatigue load times exceeded 2.8 million, the ratio of the calculated value to the measured value was less than 0.85. In conclusion, the model had its own limitations.

The parental expectation in adolescents' education is an essential factor of adolescents' social and emotional development. However, little is known about how it is related to adolescents' mobile phone addiction, especially for adolescents from low-income families. To address this issue, this study investigated the relationship between parental expectation and mobile phone addiction, and its underlying mechanisms in adolescents from low-income families. We hypothesized that parental expectation would negatively predict mobile phone addiction, and self-esteem and social anxiety would play multiple mediation roles in this relationship. Results from a sample of 1,953 Chinese adolescents in low-income families revealed that (a) parental expectation was negatively associated with adolescents' mobile phone addiction, (b) both social anxiety and self-esteem played partial and parallel mediating roles between parental expectation and mobile phone addiction, and (c) social anxiety and self-esteem mediated the association between parental expectation and mobile phone addiction sequentially. This study would advance our understanding of how proper parenting styles and social networks helped to prevent children's mobile phone addiction. The limitations and implications of this study are discussed.