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Purposes In order to improve the detection accuracy of electromagnetic abrasive particles on small particles, the influencing factors of the induced signal of one-excitation, two-in-ductive three-coil electromagnetic abrasive sensor are studied, and structural optimization and signal enhancement measures are proposed. Methods First, the mathematical model of one-excita tion, two-inductance three-coil electromagnetic abrasive sensor is established, and the model is simulated, and verified. Second, different radial positions and different sizes of abrasive grains are experimentally studied, and the relationship between the size and radial position of abrasive grains and the output signal is explored. Finally, the change law of output signal under different structural parameters is studied through finite element analysis, the parameter optimization scheme of the sensor is proposed and verified, and the shielding structure of the sensor is designed. Findings The results show that the strength of the output signal of the optimized sensor is increased by 13.75 times compared with that of the optimization period, and the minimum diameter of the ferromagnetic abrasive particles that can be detected is 82.26 μm, and the minimum diameter of non-ferromagnetic abrasive particles is 294.38 μm. The results are helpful to improve the detection accuracy on electromagnetic abrasive particles of the electromagnetic abrasive sensor.

The severe nuclear accident at the Fukushima Daiichi Nuclear Power Plant (NPP) in Japan on March 11, 2011 had a huge impact on the world’s nuclear regulatory bodies and industry. This paper summarizes the lessons learned from the Fukushima Daiichi Nuclear Accident, which include inadequacy of sitespecific extreme external natural hazards evaluation, prolonged loss of power and ultimate heat sink, insufficiency of response and management of severe accident monitoring and mitigation means and etc. It is also important to aware of that the accident can occur simultaneously on several units at a multiunit plant. In the decade after the Fukushima nuclear accident, nuclear safety improvement actions and nuclear safety regulatory standard revisions were implemented by major nuclear power countries such as the United States, Japan, France, and China. In United States, the new regulation 10CFR 50.155 Mitigation of BeyondDesignBasis Events (MBDBE) was come into forces to further enhance the capability of NPP to address the BDBE. In Japan, a new independent regulatory body, Nuclear Regulatory Authority (NRA), was established and new safety standards were released in three aspects, including design basis safety standards, severe accident measures, and safety standards relative to earthquakes/tsunamis. In France, complementary safety assessments (CSAs) were performed on all nuclear facilities, the concept hardened safety core was prepared and longterm improvement measures are still undergoing. In China, comprehensive safety inspection and external hazard safety margin assessment on NPPs were carried out, the “Code on the Safety of Nuclear Power Plant Design” (HAF102) was revised in 2016, which is a highlevel requirement on design and new nuclear safety goal, safety philosophy, and safety requirements were established in general. In this paper, the nuclear safety philosophy and requirements were elaborated in detail in the fields of practical elimination of early or large radioactive release, category of accident conditions, defense-in-depth concept, mobile equipment configuration and etc. some of which are explicit in nuclear safety review practice while others may be needed to be further clarified. In summary, certain specific suggestions of NPP safety in the future were given with international requirements and practices, as well as the domestic NPP characteristics being considered. It is also recommended that the relevant safety guides and technical positions on specific requirements should be improved constantly, a complete and logical nuclear safety regulation regime should be established, a balanced combination of deterministic and probabilistic approaches should be adapted, the specific nuclear safety and assessment criteria should be consolidated in areas such as practical elimination of early or large radioactive release, the independence between all defenseindepth levels, design extension conditions with core melting, as well as the number and configuration of mobile equipment on the multipleunit plant site.

Chirality has an important impact on chemical and biological research, as most active substances are chiral. In recent decades, metal–organic frameworks (MOFs), which are assembled from metal ions or clusters and organic linkers via metal–ligand bonding, have attracted considerable scientific interest due to their high crystallinity, exceptional porosity and tunable pore sizes, high modularity, and diverse functionalities. Since the discovery of the first functional chiral metal–organic frameworks (CMOFs), CMOFs have been involved in a variety of disciplines such as chemistry, physics, optics, medicine, and pharmacology. The introduction of defect engineering theory into CMOFs allows the construction of a class of defective CMOFs with high hydrothermal stability and multi-stage pore structure. The introduction of defects not only increases the active sites but also enlarges the pore sizes of the materials, which improves chiral recognition, separation, and catalytic reactions, and has been widely investigated in various fields. This review describes the design and synthesis of various defective CMOFs, their characterization, and applications. Finally, the development of the materials is summarized, and an outlook is given. This review should provide researchers with an insight into the design and study of complex defective CMOFs. [ABSTRACT FROM AUTHOR]

Remote sensing thematic data products are critical for assessing and analyzing geological environments, while efficient generation of thematic products is also highly significant for achieving corresponding sustainable development goals (SDGs). Currently, remote sensing thematic product generation has problems like low levels of automation and efficiency. Addressing these challenges is imperative for advancing sustainable development within the geological environment. This paper aims to address issues related to the generation of geological environment remote sensing thematic products, sorting through the overall process of remote sensing thematic product generation, exploring algorithm encapsulation, combination, and execution under technical methods for container and workflow, and relies on the Spark distributed processing architecture to achieve efficient thematic product generation supported by multiple geological environment data processing models. Finally, taking the three SDGs of SDG6, SDG11, and SDG15 as examples, we achieved the generation of a variety of thematic products such as the interpretation of water body distribution, extraction of urban informal settlements and distribution of water and soil erosion. Meanwhile, we comparatively analyzed the efficiency of thematic product generation on different processing architectures, and the experimental results further verified the feasibility and effectiveness of our proposed solution. This research provides a programme for the automated and intelligent generation of geological environment remote sensing thematic products and effectively assists the construction of sustainable development in the geological environment. [ABSTRACT FROM AUTHOR]

Evaluating the vulnerability of urban transportation systems to flood disasters can provide scientific support for urban disaster prevention and mitigation. Current methods for assessing the flood vulnerability of urban roads often overlook the internal relationships within the complex spatial composition of road networks and surface structures. In this study, based on the theory of complex networks, a dual-layer network assessment model is established for evaluating the flood vulnerability of urban transportation systems by coupling basic geographic data with road network vector data. Unlike traditional methods, this model considers the complex relationship between road network structures and ground surfaces, uncovering a correlation between road network structure and road flood vulnerability. By utilizing this model, the flood vulnerability of road networks in Shenzhen, as well as the city's spatial flood vulnerability, are quantitatively assessed. Based on the quantitative results, we create maps illustrating the distribution of road and spatial flood vulnerability in Shenzhen. The study results reflect that roads highly vulnerable to flooding are mainly located in the central urban area of the southwest, with the flood vulnerability spatially concentrated primarily in the northern and western regions. Using data from government reports, news stories, and other sources over the past five years, we compile recorded instances of urban waterlogging. The quantitative results of the model are consistent with the distribution trend in recorded waterlogging points, indicating that the model's outcomes are authentic and reliable. [ABSTRACT FROM AUTHOR]

Artificial Intelligence (AI) techniques leverage the justice system in terms of effectiveness and efficiency. AI-empowered multi-label crime classification can facilitate the precise and expedient categorization of various legal documents. Multi-label classification within the justice system has an indispensable role in achieving accurate legal categorization that invigorates case analysis, optimizes resource distribution and refines the contours of legal processes. To support this critical function, this paper proposes a temporal convolutional network (TCN)-bidirectional encoder representations from transformers (BERT)-coupled model for multi-label crime classification. The proposed method fuses the temporal formation and semantic information in the model to obtain a high-quality result. The experimental results show that the proposed method achieved the best accuracy in comparison to existing methods on a public dataset. [ABSTRACT FROM AUTHOR]

Coastal cities are increasingly vulnerable to urban storm surge hazards and the secondary hazards they cause (e.g., coastal flooding). Accurate representation of the spatio-temporal process of hazard event development is essential for effective emergency response. However, current knowledge graph representations face the challenge of integrating multi-source information with various spatial and temporal scales. To address this challenge, we propose a new information model for storm surge hazard events, involving a two-step process. First, a hazard event ontology is designed to model the components and hierarchical relationships of hazard event information. Second, we utilize multi-scale time segment integer coding and geographical coordinate subdividing grid coding to create a spatio-temporal framework, for modeling spatio-temporal features and spatio-temporal relationships. Using the 2018 typhoon Mangkhut storm surge event in Shenzhen as a case study and the hazard event information model as a schema layer, a storm surge event knowledge graph is constructed, demonstrating the integration and formal representation of heterogeneous hazard event information and enabling the fast retrieval of disasters in a given spatial or temporal range. [ABSTRACT FROM AUTHOR]

Cooperation among tourist attractions has encouraged a new form of competition among tourist destinations. Regional tourism cooperation can create win–win scenarios for participating tourist destinations, such as complementary advantages and improved comprehensive competitiveness. This study constructed a competitiveness measurement model and evaluated the competitiveness of tourist attractions. The index variables were set to modify and establish the gravity models (GMs). The cooperation network was established using Ucinet 6.0 software, and the competitive value of the tourist attractions and the structure characteristics of the network were analyzed. The results indicate that the competitiveness of tourist attractions in Jiangsu Province and Zhejiang Province is strong, while that of attractions in Anhui Province and Shanghai is weak. Tourist attractions in Shanghai, Suzhou, and Hangzhou have strong gravity for cooperation. Furthermore, the density of the cooperation network is high. The core members of the network are mainly distributed in the eastern region of the YRD and play a core role in the tourism cooperation therein. The cooperation network can be divided into four subgroups at level 2 and seven subgroups at level 3. The conclusions of this study can help the government formulate more targeted regional tourism cooperation policies. [ABSTRACT FROM AUTHOR]

Brain diseases remain a significant global healthcare burden. Conventional pharmacological therapy for brain diseases encounters huge challenges because of the blood–brain barrier (BBB) limiting the delivery of therapeutics into the brain parenchyma. To address this issue, researchers have explored various types of drug delivery systems. Cells and cell derivatives have attracted increasing interest as "Trojan horse" delivery systems for brain diseases, owing to their superior biocompatibility, low immunogenicity, and BBB penetration properties. This review provided an overview of recent advancements in cell- and cell-derivative-based delivery systems for the diagnosis and treatment of brain diseases. Additionally, it discussed the challenges and potential solutions for clinical translation. [ABSTRACT FROM AUTHOR]

Tourism experiences bring about physical or psychological feelings in tourists, which can not only leave tourists with deep memories, but also affect their behavioral intentions. Tourism experiences are meaningful only if they can be remembered and influence word of mouth and decision making. A better understanding of what influences tourism experience memory will help optimize the supply and further development of tourism destinations. This study explores the antecedents of rural tourism experience memory from the tourism supply perspective, revealing the mechanism of effect of these antecedents on tourists' tourism experience memory formation through a questionnaire-based survey of 556 participants in Xidi Village, China, and correlation and multiple regression analyses. The results show that perceptions about the supply of rural tourism destinations trigger positive emotions that, in turn, affect the formation of rural tourism experience memory. Through the mediating role of positive emotions, there is a significant correlation between perception of rural tourism destination supply and the formation of rural tourism experience memories. [ABSTRACT FROM AUTHOR]

With the development of global economic integration and the gradual formation of unified tourism markets, strengthening regional tourism cooperation has become an internal requirement of regional tourism development but also a new way of sustainably developing tourism. This study selected the key factors affecting the cooperation of tourist attractions, including the competitiveness of tourist attractions and the relationships among tourist attractions, and established an evaluation index system and mathematical model of tourist attractions' cooperation. Furthermore, the level of cooperation was evaluated. According to the value of the cooperation level, the spatial characteristics of the cooperation level were analyzed using a geographic information systems analytical method, which can better reflect the competitiveness, relationships, and overall cooperation level of tourist attractions. The results showed that the tourism competitiveness of tourist attractions was generally strong and their internal relations relatively close, and the overall tourism cooperation level was high. However, a two-dimensional four-quadrant map revealed that there were still great differences in tourism competitiveness among tourist attractions and their internal relations. Twenty-three tourist attractions exhibited weak tourism competitiveness and sparse relationships with other tourist attractions. The tourism competitiveness of tourist attractions and their internal relations and tourism cooperation level showed positive spatial autocorrelation and spatial agglomeration characteristics. The spatial differentiation of an "inverted U-shape" indicated that the cooperation level, tourism competitiveness, and mutual relations of tourist attractions were not balanced and that a stable and gradual spatial transformation had not been achieved. This study can provide valuable insights for the government to formulate policies and measures for regional tourism cooperation, carry out regional joint marketing, and help tourism enterprises design tourist routes. [ABSTRACT FROM AUTHOR]

Tourism is distinctly regional with respect to the regional distribution of tourism resources, tourist attractions and supply, and spatial continuity of tourist activities. Using point-of-interest data from 2166 tourist attractions in the Yangtze River Delta, this study analyzes the spatial distribution pattern of tourist attractions and their influencing factors by applying the methods of nearest proximity index, kernel density analysis, standard deviation ellipse, hotspot analysis, and spatial superposition analysis. The results show that the number of modern recreational tourist attractions accounts for the largest proportion. The spatial distribution pattern shows more attractions in the north than the south and more in the east than the west. The spatial density of tourist attractions in Shanghai is far greater than that in other regions, followed by Jiangsu and Zhejiang. The five types of tourist attractions show a significant aggregation state. Natural ecological tourist attractions are clustered near Nanjing and Huangshan; historical and cultural tourist attractions are formed in a T-shape by Shanghai, Hangzhou, and Nanjing; modern recreational tourist attractions are clustered in Shanghai and Hangzhou; and industrial integration tourist attractions are clustered in Shanghai, Nanjing, and Hangzhou. Physical geography, traffic, and social economy are the main factors affecting the spatial distribution of tourist attractions. [ABSTRACT FROM AUTHOR]

This study's purpose was to analyze the network structural characteristics, nodal roles, spatial structure, and evolution laws from the dual network perspective, and apply the Quadratic Assignment Procedure (QAP) to conduct correlation analysis and regression analysis on the influencing factors of tourism flow networks in the Yangtze River Delta urban agglomerations. Using a mixed-method of social network and spatial analysis, Ucinet and ArcGIS software were used to comprehensively analyze the nodes in the travel routes covered in travel notes. The results show that the density of tourism flow network increases on the whole, while the spatial difference decreases, and the overall network density value is much lower than the average of the network density of provinces. Degree centrality, closeness centrality, betweenness centrality and the core–periphery structure analysis were used to examine the tourism function, distribution function, connection function and the position of nodes in the network, and nodes were divided into various types of roles according to their function. Meanwhile, the role changes of each node in different periods were also investigated. This study also builds an evaluation model of the influencing factors of the evolution of tourism flow network structure and uses QAP to find that the tourism network is affected by factors such as tourism resource endowment, transportation convenience, economic development level, tourism reception and service capacity. The research results are helpful for the Chinese government and tourism enterprises to understand the spatial behavior of tourists and its evolution rules, and to clarify the role and status of node cities in the tourism flow network and their influencing factors. It is of great significance for the formulation of joint marketing measures and promotion of the sustainable development of tourism in the Yangtze River Delta urban agglomeration. [ABSTRACT FROM AUTHOR]

Objective: This article explores the effect of preoperative health education, in the form of animation videos, on postoperative self-reported pain levels and anxiety in femoral fractures. Methods: Ninety cases of femoral fracture were divided at random into the oral instruction group, the recorded video group, and the animation video group, with 30 cases in each group. Sociodemographic data were collected the day before surgery. Health education was then offered in one of three ways: orally, using a recorded video, or using an animation video. On days 2, 4, and 7 after surgery, the state-trait anxiety inventory (STAI) and the visual analog scale (VAS) were used to assess postoperative anxiety and pain levels, respectively, in the participants. Results: At different time points during the evaluation, total anxiety scores in the animation and recorded video groups were significantly lower than in the oral instruction group (P < 0.01), and the pairwise comparisons indicated statistically significant differences (F = 11.04, 10.06, 10.37, P < 0.01). However, the levels of postoperative pain in the animation and recorded video groups were not significantly different (P > 0.05). STAI scores in the three groups were found to have significant interactions with the measurement time (F = 6.74, P < 0.01). However, there were no apparent interactions between the VAS score and the measurement time (F = 1.31, P > 0.05) in the three groups. Conclusion: Preoperative health education with the aid of multimedia is more effective than oral instruction in lowering patients' postoperative anxiety and pain levels. In addition, animation videos are superior to recorded videos in mitigating postoperative anxiety. Whether the two approaches differ in reducing postoperative pain in bone fractures remains to be further tested. [ABSTRACT FROM AUTHOR]

The substitution of C for N in graphitic carbon nitride (g-C3N4) can promote π-electron availability and increase photocatalytic activity, but the low specific surface area still limits its performance. Herein, porous C-doped g-C3N4 was prepared by the uracil-mediated supramolecular assembly of melamine and cyanuric acid. The as-prepared catalyst exhibited a high photocatalytic hydrogen evolution rate of 2352 μmol g−1 h−1 under visible light irradiation (λ ≥ 420 nm), which was 28 times that of g-C3N4 (83 μmol g−1 h−1), due to the porous architecture and C-doping effect. The porous architecture endowed the catalyst with a large specific surface area (79.4 m2 g−1) and great light utilization efficiency in the visible light region between 500 and 750 nm. In addition, C-doping modified the energy band structure of g-C3N4 to a narrow band gap (from 2.92 eV to 2.78 eV) and enhanced the separation efficiency of photogenerated carriers. [ABSTRACT FROM AUTHOR]

This study explores the spatial structure of regional tourism cooperation networks among 27 cities in the Yangtze River Delta from the perspective of supply and demand. Data from the supply network were collected from official news released by the Chinese government and quotations for tour routes published by travel agencies. Travel notes published on tourists' blog community platforms about their travel experiences were used as source data for the demand network. The degree of cooperation between the cities was analyzed based on the frequency of occurrence and co-occurrence of information on tourist attractions or cities in the Yangtze River Delta region in tourist notes, tourist route quotes, and official news. This study divides 27 cities in the Yangtze River Delta region into three categories: those where supply matches demand (e.g., Shanghai and Nanjing), nine cities where there is a demand lag (e.g., Zhenjiang), and 16 cities where there is a supply lag (e.g., Wuxi). Investigating the differences between the supply and demand networks is helpful to understand the effectiveness of regional tourism cooperation mechanisms and government policies, which is crucial for the sustainability and good governance of regional tourism. [ABSTRACT FROM AUTHOR]

This study aimed to examine the spatial structure of the tourist attraction cooperation network in the Yangtze River Delta, from the perspective of tourist flow. This study conducted spatial and social network analyses of 470 popular tourist attractions in the Yangtze River Delta region of China, accounting for the occurrence and co-occurrence of tourist attraction information in tourist travel notes. The analyzed tourist attractions show an obvious spatial agglomeration effect, including four high-density agglomeration areas and two medium-density agglomeration areas. Degree centrality, closeness centrality, and betweenness centrality were used to examine the tourism function, distribution function, and connection function of nodes in the network; nodes were divided into various types of roles according to their function. There are eight condensed subgroups, but their scales are unbalanced. In these condensed subgroups, several tourist attractions with an intermediate function can be selected as transit and stopover points on tourist routes. This study can contribute to the understanding of tourists' spatial behavior, clarify the role and status of nodes in the cooperation network of tourist attractions based on tourism flow, and help them to formulate measures for the joint marketing of tourist attractions, and promote the development of tourism in the Yangtze River Delta region. [ABSTRACT FROM AUTHOR]

Di-(2-ethylhexyl) phthalate (DEHP), the most extensively used phthalate acid esters (PAEs), poses a potential risk to human and environment. A novel bacterial strain, Rhodococcus sp. LW-XY12, with efficient PAE-degrading capability, was isolated from activated sludge. Strain LW-XY12 could degrade 96.91 ± 0.68% of DEHP (500 mg L−1) within 32 h. The degradation curves of DEHP (50–1500 mg L−1) and PAE mixture (500 mg L−1 each) fitted well with the modified Gomperz kinetics model. DEHP metabolic pathway was reconstructed by using genome annotation and metabolic intermediate analyses. The DEHP metabolic pathway might comprise de-esterification and β-oxidation. Homologous modeling and molecular docking analysis revealed that DEHP and MEHP (mono-(2-ethylhexyl) phthalate) could be bound to putative carboxylesterase (KXC42_04905) via hydrogen bonding and hydrophobic interaction. A conserved catalytic triad (Ser195-Glu319-His412) might act as an active protein pocket and catalyze the hydrolysis of DEHP. Carboxylesterase (KXC42_04905) could hydrolyze ester bond and a possible mechanism underlying ester bond hydrolysis catalyzed by the carboxylesterase was proposed. Protocatechuate 3,4-dioxygenase, 3-oxoadipate CoA-transferase, benzoate 1,2-dioxygenase, catechol 1,2-dioxygenase, and catechol 2,3-dioxygenase transcripts were detected and significantly up-regulated under DEHP induction. This study sheds light on the functional genes associated with DEHP degradation and metabolic mechanism in this versatile bacterium for degradation of PAEs. [Display omitted] • Strain Rhodococcus sp. LW-XY12 degraded DEHP and other PAE homologs efficiently. • DEHP and PAE mixture degradation curves fitted well with the modified Gompertz model. • Interactions between a carboxylesterase and DEHP and underlying mechanism were explored. • Strain LW-XY12 may degrade catechol through ortho- and/or meta-cleavage pathways. • DEHP metabolism pathway was reconstructed by metabolite analyses and genomic annotation. [ABSTRACT FROM AUTHOR]