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Forest products trade has a critical role to play in both global economic development and environmental protection. Based on the trade data of global forest products, raw forest products, and processed forest products from 2000 to 2020, this paper constructed a trade network and analyzed its pattern by using indicators such as density, average distance, out- strength, and in-strength. The results show that from 2000 to 2020, the global trade network of forest products has been increasingly connected. Compared with the trade of raw material forest products, the trade network of processed forest products is more closely connected and its transport efficiency is higher. Countries with high GDP such as USA, China, and Germany are leading trading countries in forest products. Countries with abundant forest resources are the major exporters of raw forest products, while labor- and capital-abundant countries are major exporters of processed forest products. Countries with abundant labor and capital and high GDP are the main importers of raw forest products. Key words: complex network, forest products, trade patterns, 1. Introduction Forest products are an indispensable and important resource for the construction of the national economy, and also an important bulk international trade product in the world. The global [...]

BackgroundVirtual and augmented reality (VAR) represents a combination of current state-of-the-art computer and imaging technologies and has the potential to be a revolutionary technology in many surgical fields. An increasing number of investigators have developed and applied VAR in hip-related surgery with the aim of using this technology to reduce hip surgery–related complications, improve surgical success rates, and reduce surgical risks. These technologies are beginning to be widely used in hip-related preoperative operation simulation and training, intraoperative navigation tools in the operating room, and postoperative rehabilitation. ObjectiveWith the aim of reviewing the current status of virtual reality (VR) and augmented reality (AR) in hip-related surgery and summarizing its benefits, we discussed and briefly described the applicability, advantages, limitations, and future perspectives of VR and AR techniques in hip-related surgery, such as preoperative operation simulation and training; explored the possible future applications of AR in the operating room; and discussed the bright prospects of VR and AR technologies in postoperative rehabilitation after hip surgery. MethodsWe searched the PubMed and Web of Science databases using the following key search terms: (“virtual reality” OR “augmented reality”) AND (“pelvis” OR “hip”). The literature on basic and clinical research related to the aforementioned key search terms, that is, studies evaluating the key factors, challenges, or problems of using of VAR technology in hip-related surgery, was collected. ResultsA total of 40 studies and reports were included and classified into the following categories: total hip arthroplasty, hip resurfacing, femoral neck fracture, pelvic fracture, acetabular fracture, tumor, arthroscopy, and postoperative rehabilitation. Quality assessment could be performed in 30 studies. Among the clinical studies, there were 16 case series with an average score of 89 out of 100 points (89%) and 1 case report that scored 81 (SD 10.11) out of 100 points (81%) according to the Joanna Briggs Institute Critical Appraisal Checklist. Two cadaveric studies scored 85 of 100 points (85%) and 92 of 100 points (92%) according to the Quality Appraisal for Cadaveric Studies scale. ConclusionsVR and AR technologies hold great promise for hip-related surgeries, especially for preoperative operation simulation and training, feasibility applications in the operating room, and postoperative rehabilitation, and have the potential to assist orthopedic surgeons in operating more accurately and safely. More comparative studies are necessary, including studies focusing on clinical outcomes and cost-effectiveness.

Abstract During the oscillating twin-roll strip casting process, the quality of final products is directly influenced by the flow field distribution of molten metal in the pool. The variation in the flow field is caused by oscillating roller benefits, for homogeneous distribution of strip impurity, and decreasing the grain size. Thus, the quality of the strip could be improved. A numerical model was developed using the multiphase flow technology, coupled with heat transfer, fluid flow, solidification, and oscillation. Furthermore, a transient algorithm was adopted for simulating the oscillating twin-roll strip casting process of AlSi9Cu3 and 3104 aluminum alloy. This paper focuses on the flow distribution in the pool, in comparison with the traditional vertical twin-roll strip casting process, while the amplitude or frequency is changing with the definite value of casting velocity, roller diameter, nozzle angle, and the strip thickness. Consequently, the conclusions were experimentally validated by oscillating twin-roll 3104 aluminum alloy strip casting. Vibrating casting technology can change the flow field in the pool by vibration, which can improve the quality of the strip core.

In this paper, an intelligent computer method for yarn surface grading is developed to analyze yarn board image and objectively evaluate yarn quality according to ASTM D2255.Both statistical features measuring the overall performance and relative features measuring salient regions are elaborately designed and selected. Statistical features are extracted to characterize the yarn body and hairiness. In relative feature extraction, a two-scale attention model is proposed and developed, which can fully imitate human attention at different observation distances for the whole and detailed yarn information. Global and individual Probabilistic Neural Networks (PNNs) are then designed for yarn quality evaluation based on eight-grade and five-grade classifications. A database, covering eight yarn densities (Ne7~ Ne80) and different surface qualities, was constructed with 296 yarn board images for the evaluation. The accuracy for eight- and five-grade global PNNs are 92.23 and 93.58%, respectively, demonstrating a good classification performance of the proposed method. [ABSTRACT FROM AUTHOR]

Antioxidant activity of glycyrrhetinic acid and its metal-containing complexes was investigated. The antioxidant activity behaviours of glycyrrhetinic acid and its metal-containing complexes (coordinated with Fe3+, Cu2+, Zn2+, and Ca2+) on free radicals (•OH, O2 •–, ROO•, and DPPH) was investigated by graphene modified glassy carbon electrode. The free radical-scavenging capacity of glycyrrhetinic acid and its metalcontaining complexes was calculated, respectively. The scavenging capacity order on the •OH radical was glycyrrhetinic acid-Cu > glycyrrhetinic acid-Zn > glycyrrhetinic acid-Fe > glycyrrhetinic acid-Ca > glycyrrhetinic acid. The scavenging order on the O2 •– radical was glycyrrhetinic acid-Zn > glycyrrhetinic acid-Cu > glycyrrhetinic acid-Ca > glycyrrhetinic acid-Fe > glycyrrhetinic acid. The scavenging order on the DPPH radical was glycyrrhetinic acid-Zn > glycyrrhetinic acid–Ca > glycyrrhetinic acid-Fe > glycyrrhetinic acid-Cu > glycyrrhetinic acid. The scavenging order on the ROO• was glycyrrhetinic acid-Fe > glycyrrhetinic acid > glycyrrhetinic acid-Zn > glycyrrhetinic acid-Cu > glycyrrhetinic acid-Ca. Except for the ROO• radical, the scavenging capacity of glycyrrhetinic acid metal-containing complexes with free radicals was significantly higher than that of glycyrrhetinic acid. [ABSTRACT FROM AUTHOR]

Electrochemical characterization of the free radical scavenging of baicalein was performed. A sensitive and selective electrochemical sensor for the characterization of the reaction between free radicals and baicalein was fabricated based on a nanoaluminum oxide modified carbon paste electrode. The modified carbon paste electrode showed excellent electrocatalytic activity for the characterization of free radical scavenging capacity of baicalein. In 0.2 M phosphate buffer at pH 7.4, a pair of well-defined cyclic voltammetric oxidation peaks of baicalein appeared with the maximum at 700 mv. The superoxide anion radical, hydroxyl radical, lipid peroxyl radical, and of 2,2-diphenyl-l-picrylhydrazyl were used for investigating the free radical scavenging of baicalein. Baicalein showed varying scavenging capacities to these free radicals. The scavenging capacity of baicalein with the hydroxyl radical was the highest, followed by baicalein with the lipid peroxyl radical, 2,2-diphenyl-l-picrylhydrazyl, and the superoxide anion radical. [ABSTRACT FROM AUTHOR]

Tracer fiber measurement is a popular and effective method to study yarn internal structure. In this method, a series of consecutive yarn images are stitched into panorama, and yarn boundaries and tracer fiber are extracted for further analysis. Currently, the image mosaic and segmentation of tracer fiber images largely involve manual operation because the existing image processing methods are generally not capable in most cases. Therefore, this study aims to develop an intelligent computer method for automatic mosaic and segmentation of tracer fiber images. In this study, an extended QRS complex detection method is developed for tracer fiber detection. In the image mosaic, a decision function, integrating several matching functions extracted from the tracer fiber and gradient image, is proposed to identify the optimal stitching position. The QRS complex is a name for the combination of Q wave, R wave and S wave on an electrocardiogram (ECG), which reflects the rapid depolarization of the right and left ventricles. In image segmentation, a baseline fitting method is used to eliminate the effect of uneven background for identifying yarn boundaries from the binary image. Finally, an objective method is proposed to evaluate the qualities of the image mosaic and segmentation of the proposed method. [ABSTRACT FROM PUBLISHER]

Background: Virtual and augmented reality (VAR) represents a combination of current state-of-the-art computer and imaging technologies and has the potential to be a revolutionary technology in many surgical fields. An increasing number of investigators have developed and applied VAR in hip-related surgery with the aim of using this technology to reduce hip surgery-related complications, improve surgical success rates, and reduce surgical risks. These technologies are beginning to be widely used in hip-related preoperative operation simulation and training, intraoperative navigation tools in the operating room, and postoperative rehabilitation., Objective: With the aim of reviewing the current status of virtual reality (VR) and augmented reality (AR) in hip-related surgery and summarizing its benefits, we discussed and briefly described the applicability, advantages, limitations, and future perspectives of VR and AR techniques in hip-related surgery, such as preoperative operation simulation and training; explored the possible future applications of AR in the operating room; and discussed the bright prospects of VR and AR technologies in postoperative rehabilitation after hip surgery., Methods: We searched the PubMed and Web of Science databases using the following key search terms: ("virtual reality" OR "augmented reality") AND ("pelvis" OR "hip"). The literature on basic and clinical research related to the aforementioned key search terms, that is, studies evaluating the key factors, challenges, or problems of using of VAR technology in hip-related surgery, was collected., Results: A total of 40 studies and reports were included and classified into the following categories: total hip arthroplasty, hip resurfacing, femoral neck fracture, pelvic fracture, acetabular fracture, tumor, arthroscopy, and postoperative rehabilitation. Quality assessment could be performed in 30 studies. Among the clinical studies, there were 16 case series with an average score of 89 out of 100 points (89%) and 1 case report that scored 81 (SD 10.11) out of 100 points (81%) according to the Joanna Briggs Institute Critical Appraisal Checklist. Two cadaveric studies scored 85 of 100 points (85%) and 92 of 100 points (92%) according to the Quality Appraisal for Cadaveric Studies scale., Conclusions: VR and AR technologies hold great promise for hip-related surgeries, especially for preoperative operation simulation and training, feasibility applications in the operating room, and postoperative rehabilitation, and have the potential to assist orthopedic surgeons in operating more accurately and safely. More comparative studies are necessary, including studies focusing on clinical outcomes and cost-effectiveness., (©Peng Sun, Yao Zhao, Jie Men, Zhe-Ru Ma, Hao-Zhuo Jiang, Cheng-Yan Liu, Wei Feng. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 10.03.2023.)