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The orthogonal experiment method was used to investigate the heat transfer performance of the gravity heat pipe under the influence of multiple factors such as types of working fluid, filling rate, and the aspect ratio. The Multi-index weighting method and rescaled range analysis were introduced to analyze the experimental results to propose an appropriate combination scheme of factors for the best heat transfer performance of the gravity heat pipe. The results show that gravity heat pipe can effectively reduce the internal temperature of the coal pile, thereby inhibiting the increase of the temperature of the coal pile. Moreover, the cooling capacity and effective pore radius of gravity heat pipe are positively correlated with the temperature of the coal pile. Specifically, when the coal pile temperature is about 70 ℃, the most appropriate combination of various factors is as follows, the working fluid is Al2O3-water nanofluid, the liquid filling rate is 15%, and the aspect ratio is 25.0. When the temperature of the coal pile rose to 210 ℃, the most appropriate combination of each factor is as follows, the working fluid is Al2O3-water nanofluid, the liquid filling rate is 25%, and the aspect ratio is 25.0.

The morphology of the material has a great influence on its flame retardancy. In order to study the effects of magnesium hydroxide with different morphologies on the flame retardancy of epoxy resin, magnesium chloride and magnesium sulfate were used as raw materials to prepare magnesium hydroxide with rod, flake and flower, and were added to epoxy resin to prepare epoxy resin composite to explore the flame retardancy and the flame retardant mechanism. The results show that the diameter of rod magnesium hydroxide ranges from 250 nm to 500 nm and the length is about 5 μm. The flaky magnesium hydroxide has a hexagonal sheet structure with a size of 100 nm. The size of flower ball magnesium hydroxide is 1~2 μm. When the addition of magnesium hydroxide is 3%, the flame retardancy of epoxy resin is improved as: flake>flower>rod. Compared with pure epoxy resin, the addition of flaky magnesium hydroxide reduceds the TSP by 35.1%, the PHRR by 36.6%, and the PCOP by 39.4%. The research provides the direction for the application of magnesium hydroxide in polymers. [ABSTRACT FROM AUTHOR]

Objective To explore the relationship between the levels of serum 8-hydroxy deoxyguanosine (8 - OHdG) and malondialdehyde (MDA) and cognitive dysfunction in patients with Parkinson's disease (PD). Methods From February 2021 to February 2022, 126 patients with PD in The Affiliated Hospital of Xuzhou Medical University were divided into normal cognitive function group (PDN group, n = 41), mild cognitive impairment group (PD-MCI group, n = 47) and Parkinson's disease dementia group (PDD group, n = 38), and 50 healthy subjects were selected as control group. Hoehn-Yahr staging was used to evaluate the severity of patients with PD during the "close" period of anti-PD drugs, and the motor function of patients with PD was evaluated by the Unified Parkinson's Disease Rating Scale III (UPDRS III). Montreal Cognitive Assessment (MoCA) was used to evaluate the severity of cognitive dysfunction at rest and in the "on" period of anti-PD drugs, and the serum 8-OHdG and MDA of PD patients and controls were collected. Pearson and partial correlation analyses were used to analyze the correlation between the levels of serum 8-OHdG and MDA and MoCA score in PD patients. Univariate and multivariate Logistic regression analyses were used to analyze the influencing factors of cognitive dysfunction in PD patients. The efficacy analysis of serum 8-OHdG and MDA levels in predicting the risk of cognitive dysfunction in PD patients was carried out by using receiver operating characteristic curve (ROC curve). Results The results of correlation analysis showed that there was a negative correlation between the MoCA score and the duration (r = - 0.241, P = 0.007), Hoehn-Yahr staging (r = - 0.333, P = 0.007), 8-OHdG (r = - 0.310, P = 0.000) and MDA (r = - 0.291, P = 0.004) in PD patients. The results of Logistic regression analysis showed that the elevated levels of 8-OHdG (OR = 1.335, 95%CI: 1.137-1.568; P = 0.000) and MDA (OR = 2.928, 95%CI: 1.676-5.115; P = 0.000) were risk factors for cognitive dysfunction in PD patients. The results of ROC curve showed the areas under the curve of 8-OHdG, MDA and their combination in predicting cognitive dysfunction in PD patients were 0.831 (95%CI: 0.761-0.902, P = 0.000), 0.846 (95%CI: 0.775-0.916, P = 0.000) and 0.922 (95%CI: 0.878-0.966, P = 0.000), respectively. Conclusions The detection of 8-OHdG and MDA in peripheral blood is expected to be a serum marker to evaluate the severity of cognitive dysfunction in patients with PD, and to predict cognitive dysfunction in patients with PD. [ABSTRACT FROM AUTHOR]

Vestibular evoked myogenic potentials (VEMPs), a key electrophysiological technique, is extensively utilized for the clinical evaluation of vestibular function. Patients with Parkinson's disease (PD) often have vestibular dysfunction, with VEMPs abnormalities being the most common. Based on the brief introduction of VEMPs technique, this review summarizes the features of VEMPs abnormalities, its association with clinical phenotype and underlying pathophysiological basis in patients with PD, so as to provide guidance for clinical research and practical application. [ABSTRACT FROM AUTHOR]

Objective: To establish a new method for the rapid detection of Pseudomonas aeruginosa in packaged drinking water using colloidal gold-based lateral flow immunochromatographic strips. Methods: 1 mg/mL sheep anti-mouse antibody and 1 mg/mL streptavidin (SAV) were sprayed onto a nitrocellulose (NC) membrane by using a membrane sprayer at a rate of 0.5 μL/cm, and then the antibody labeled with fluorescein isothiocyanate (FITC) was conjugated to the surface of colloidal gold by electrostatic adsorption, and the resulting conjugate was added dropwise to the gold standard pad. The amplification products were added dropwise to the fully assembled lateral flow immunochromatographic strip, and the results were judged based on the positions of the control (C) and test (T) lines generated. Results: The method was able to specifically identify P. aeruginosa in packaged drinking water in 3 min with a detection limit of 1 CFU/250 mL, which was more sensitive than agarose gel electrophoresis. Conclusion: The lateral flow immunoassay method was characterized by high sensitivity, high specificity, simplicity and portability, and was suitable for real samples.

Objective To explore the related factors of lymph node metastasis in early gastric cancer and to analyze the clinical efficacy between laparoscopic D2 radical resection and endoscopic submucosal dissection (ESD). Methods A retrospective cohort study was conducted on 404 patients with early gastric cancer undergoing surgical treatment in our hospital from June 2018 to June 2022 were recruited in this study. According to their surgical treatment, they were divided into laparoscopy group (n=271) and ESD group (n=133). The lymph node metastases were compared in the patients with different clinical features, and the factors affecting lymph node metastasis were analyzed with multivariate logistic regression analysis. The lymph node metastasis rate of patients with absolute and expanded indications of ESD was calculated. Kaplan-Meier survival analysis was used to compare the long-term efficacy of ESD and laparoscopic D2 radical resection in these patients. Stratified regression analysis was applied to explore the relationship between surgical methods and long-term outcome in them. Results In the 404 patients with early gastric cancer, the rate of lymph node metastasis was 12.38% (50/404). Univariate analysis showed that 7 clinical features, such as ulcer, tumor pathological features and pathological differentiation, were related to lymph node metastasis. Multivariate logistic regression analysis revealed that low differentiation and tumor infiltration depth of submucous membrane (SM) were related factors affecting lymph node metastasis in early gastric cancer. The overall survival rate was 96.29% (389/404) in the 404 patients, 96.31% in the laparoscopic group and 96.24% in the ESD group, and no statistical difference was seen between the 2 groups (P>0.05). There was no obvious difference in 5-year survival rate between the patients who met the absolute indications for ESD and underwent laparoscopic D2 radical surgery and those receiving ESD treatment (96.00% vs 96.55%), and between those who were in accordance with the expanded indications for ESD and underwent laparoscopic D2 radical surgery and those receiving ESD treatment (94.74% vs 91.67%). After adjusting the clinical features such as lesion size, pathological differentiation and depth of tumor invasion by stratified regression analysis, the mode of operation for early gastric cancer was still correlated with the long-term efficacy (β=1.173, P=0.003). Conclusion The depth of tumor infiltration and differentiation are closely related to lymph node metastasis in early gastric cancer patients. The efficacy of laparoscopic D2 radical surgery on the patients with absolute and expanded indications for ESD is comparable to that of ESD treatment.

[Introduction] The "carbon peak and neutrality" strategy has put forward a new path for China's energy development, which restricts the use of traditional fossil energy, and promotes the Chinese government to increase its support for the development of the new energy industry. Photovoltaic, as a new energy which is the most accessible and has the widest coverage, has become the first choice to solve the current energy and environmental problems. However, if we want to increase its market scale and realize the vigorous development of photovoltaic industry, it is necessary to find out and solve the pain points and difficulties of the current stage. [Method] China's policy on the whole photovoltaic industry chain was combed and analyzed to explore the shortcomings of the photovoltaic industry incentive policy. Based on the data from 33 sample enterprises in the A-share market from 2000 to 2021, the DEA model was built and the integrated innovation benefits and scale benefits of China's PV industry under the guidance of policy were explored. And using the panel regression analysis method, the different impacts of different regional policies on the innovation capacity of the upstream, middle and downstream enterprises of the PV industry. were explored. [Result] The research shows that the policy subsidies have a more significant impact on the innovation benefits of upstream photovoltaic enterprises, which is positively correlated with the development of enterprises in the eastern region. While in the western region, the opposite is the case, and there are certain regional differences. [Conclusion] It is necessary to improve the preferential policy strength in the photovoltaic technology innovation level, and carry out a reasonable industry chain planning and layout in combination with the regional advantages.

The Junggar Basin is known for its high potential of petroleum resources, showcasing significant oil and gas discoveries across various layers. However, the potential of utilizing the thick mudstone of the Upper Triassic as a viable source rock in the basin remains uncertain. Therefore, an urgent need exists to assess the Upper Triassic source rock across the basin and predict the distribution of effective source rocks. This evaluation is crucial for informing future exploration strategies in this layer. To shed light on the spatiotemporal distribution characteristics and hydrocarbon generation potential of the Upper Triassic source rocks in the Junggar Basin, as well as to determine the hydrocarbon generation intensity within the effective hydrocarbon kitchen's distribution range, a comprehensive evaluation was conducted. This evaluation involved assessing organic matter abundance, type, and maturity of the Upper Triassic source rock across the basin using various geochemical parameters derived from data collection, profile measurement, drill cuttings observation and sampling, and organic geochemistry testing. Key parameters were then selected, and a multi-level fuzzy mathematical evaluation method was employed to map out the development range of the effective hydrocarbon kitchen. The findings indicate that the Upper Triassic source rock exhibits a broad distribution range spanning the entire basin, with considerable thickness (reaching up to 350 m) and significant burial depth in the central region (up to 11 000 m). The total organic carbon (TOC) content of source rocks varies from 0.75% to 8.30%, with an average value of 1.74%. Additionally, the average values of S1+S2 and chloroform asphalt "A" are 2.78 mg/g and 0.354%, respectively. The predominant organic matter types in the area are type Ⅲ and type Ⅱ2, indicating a dominance of terrestrial higher plant inputs. The favorable kerogen types are primarily located from the western sag to the Fukang Sag. The thermal evolution of the organic matter ranges from low-maturity to mature stages, with some areas reaching high to over-maturity levels. As per the evaluation criteria for hydrocarbon generation potential of coal-bearing mudstone in China, the Upper Triassic mudstone generally represents poor to medium-quality source rocks with significant hydrocarbon generation potential, particularly for gas. The key hydrocarbon source kitchens are situated from the western part of the Fukang Sag to the eastern part of the Shawan Sag in the central depression, and in the Huomatu Anticline of the southern margin thrust belt. Within these areas, the Ro value of the source rock exceeds 1.3%, with oil and gas generation intensities reaching 50×104 t/km2 and 3×108 m3/km2, respectively.

Home-based hospice care for the elderly is an important medical service model aimed at providing comprehensive medical and social support for the elderly. However, due to the special needs and difficulties in nursing of the elderly, a single medical service model often fails to meet their needs. Therefore, establishing a collaborative medical and social worker intervention model for elderly home care and shared care has become an important research direction. This article aims to investigate the sharing model of medical and social workers participating in home-based hospice care under the background of population aging, explore a home-based hospice care model suitable for China's elderly care system, standardize and guide the participation of medical and social workers in home-based shared care, leverage the intervention role of social workers, and meet the needs of patients at home. (老年人居家安宁疗护是一种重要的医疗服务模式, 由于老年人的特殊性和照护难度, 单一的医疗服务模式往往难以满足老年人的需求。因此, 建立医务社工联动介入老年居家安宁疗护共照护理模式成为了一个重要的研究方向。本研究探讨老龄化趋势下医务社工联动参与居家安宁疗护的共照模式, 旨在探索适合我国养老体系下的居家安宁疗护模式, 规范化指引医务社工参与居家共照工作, 发挥社工介入作用, 为老年人提供全面的医疗和社会支持。)

Objective To investigate the effect of narrative nursing combined with Traditional Chinese Medicine foot soaking and auricular acupoint pressing in the treatment of post-stroke sleep disorder. Methods From June 2022 to December 2022, 80 patients with sleep disorder after stroke admitted to the Rehabilitation Department of Beijing Longfu Hospital were selected and randomly divided into a control group and a study group, with 40 patients in each group. Patients in the control group received routine nursing intervention, and those in the study group were given narrative nursing combined with Traditional Chinese Medicine foot soaking and auricular acupoint pressing in addition to the routine nursing. Pittsburgh Sleep Quality Index(PSQI) scale was used to measure patient’s sleep quality. Hamilton Anxiety Scale (HAMA) and Hamilton Depression Scale (HAMD) were performed to evaluate the patient’s anxiety and depression level. Results The PSQI score was decreased in both two groups after intervention, and PSQI score in the study group was lower than that in the control group (P＜0. 01). The HAMA and HAMD scores were decreased in both two groups after intervention, and HAMA and HAMD scores in the study group were lower than that in the control group (P＜0. 01). Conclusion The narrative nursing combined with Traditional Chinese Medicine foot soaking and auricular acupoint pressing can effectively improve the sleep quality of stroke patients with sleep disorder. (目的 探讨叙事护理联合中药泡足和耳穴贴压治疗脑卒中后睡眠障碍的效果。方法 2022年6月—12月, 选取北京市隆福医院康复科收治的脑卒中后睡眠障碍患者80例, 采用随机数字表法分为对照组和研究组, 各40例。对照组患者将接受常规护理干预, 研究组在对照组的基础上接受叙事护理联合中药泡足和耳穴贴压治疗, 采用匹兹堡睡眠质量指数(PSQI)评价患者睡眠质量, 采用汉密尔顿焦虑量表(HAMA)评分和汉密尔顿抑郁量表(HAMD)评分评估患者焦虑和抑郁程度。结果 干预后, 两组PSQI量表总分较干预前下降, 且研究组PSQI量表总分低于对照组, 差异有统计学意义(P＜0. 01)。干预后, 两组HAMA和HAMD量表总分较干预前下降, 且研究组HAMA和HAMD量表总分低于对照组, 差异有统计学意义(P＜0. 01)。结论 叙事护理联合中药泡足和耳穴贴压能有效改善脑卒中后睡眠障碍患者的睡眠质量和负性情绪。)

Objective The 509 Daobanxi deposit in the West Kunlun orogenic belt is a newly discovered large pegmatite-type lithium-polymetallic deposit in northwestern China. As a typical granite pegmatite lithium deposit in the region, the metallogenic characteristics and pegmatite evolution of the 509 Daobanxi deposits are of great significance for understanding the entire lithium-polymetallic mineralization process of the West Kunlun metallogenic belt. The granite pegmatites contain assemblages of plagioclase, spodumene, quartz, muscovite, etc., exhibiting strong mylonization and forming typical ductile deformation characteristics in the 509 Daobanxi deposit. Quartz, an essential mineral in granite pegmatite, is ideal for tracking pegmatite's mineralization process and studying the deformation behavior of continental rocks in long-term geological history. Methods To study the late-stage emplacement process of pegmatite evolution, comprehensive analyses were conducted on the quartz deformation structures measurements, fluid inclusion temperature, and quartz trace elements for the 509 Daobanxi granite pegmatites. Cathodoluminescence (CL) analysis of quartz in deformed granite pegmatite samples was performed to reveal the compositional zoning of Ti in quartz. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used to analyze 64 points from samples Zk2707-9 and Zk1107-2. Results The minerals of spodumene and plagioclase in deformed pegmatites primarily show brittle fracturing characteristics, with the features of rigid body deformation and the muscovite presence of mica-fish. Meanwhile, the conspicuous feature is that quartz grains mainly develop dynamic recrystallization and contain subgranis. According to the microstructural characteristics of spodumene, plagioclase, and quartz, the deformation temperature of mylonitized granite pegmatite is 300~400℃. The CL images of quartz bands in the granite pegmatite samples have no apparent zoning, indicating that the Ti content reaches a relative equilibrium state in the quartz deformation stage. The LA-ICP-MS analysis shows quartz from the 509 Daobanxi granite pegmatites contains a lower concentration of Ti (1.03 ×10−6 to 7.67×10−6 and 1.04 ×10−6 to 6.75×10−6), suggesting relatively lower deformation temperatures. The Ti-in-quartz thermobarometry indicates quartz deformation temperatures ranging from 371 to 398°C and 351 to 377°C, respectively. The thermometric measurement shows that homogenization temperatures of the quartz fluid inclusions in pegmatite varied from 260℃ to 283℃, likely recording the temperature of the late stage of pegmatite evolution. Conclusion Comprehensive analysis shows that the 509 Daobanxi granite pegmatites underwent a period of intense ductile deformation during the emplacement process, with low temperature and high strain rate. The emplacement of pegmatite is a product of the rapid cooling process, and the grain size reduction caused by dynamic recrystallization (GBM) under high-stress and low-temperature conditions profoundly changed the rheological properties of pegmatite. The supercooling process from ~400℃ to ~260℃ (ΔT=140℃±), resulting in less rapid mineral crystalline new nuclei in pegmatites, is more conducive to the formation of coarse quartz and other mineral particles, forming the significant characteristics of granite pegmatites. [ Significance ]In fact, the emplacement process of granitic pegmatites remains a puzzle, and high-quality, accurate systematic work is needed to understand the evolution process and behavior of granite pegmatite. By studying the 509 Daobanxi granite pegmatites, we proposed that the pegmatite emplacement was a product of the rapid cooling process, and supercooling plays an essential role in pegmatite emplacement. Similar deformation characteristics are widely developed in the Tugeman lithium deposit in the Altyn Tagh area and the Jiajika lithium deposit in the western Sichuan. Although the current work is preliminary, our study provides some clues for exploring the emplacement process of granitic pegmatites.

Bipolar plates play a role in electron transfer, gas distribution, water management, supporting membrane electrode assembly in the proton exchange membrane fuel cell (PEMFC) and is also a key component to ensure low cost of fuel cell stack. In this paper, bipolar plate materials (metal, graphite and composite materials), functions, advantages and challenges are reviewed. Among them, the composite graphite bipolar plate stands out with its long cycle life and high corrosion resistance, and has received high attention in recent years. The factors related to the conductive network formed by graphite (including the size and shape of filler and the auxiliary filler bridging graphite particles), the composition and curing conditions of polymer, and the influence of the molding process conditions on the properties were discussed in this paper. In the future, the development of composite graphite bipolar plates with excellent comprehensive performance, making existing formulas and forming methods suitable for large-scale production by mastering and optimizing the balance between polymer structure and reaction path on their performance, will greatly enhance the large-scale application of proton exchange membrane fuel cells in more fields.

Objective To explore the predictive value of serum amyloid A1 (SAA1) in acute myocardial infarction (AMI). Methods A total of 139 patients with AMI and 146 patients with non coronary atherosclerotic heart disease admitted to the China-Japan Union Hospital of Jilin University from September 2017 to April 2019 were selected as the research objects. Enzyme linked immunosorbent assay (ELISA) was used to determine the level of SAA1 in plasma. Logistic regression was used to analyze the independent influencing factors of AMI, and receiver operating characteristic (ROC) curve was used to analyze the value of SAA1 in the diagnosis of AMI. Results The level of SAA1 in the AMI group was lower than that in the control group [2.62 (2.08,3.21) ng/mL vs 5.18 (3.24,8.27) ng/mL, Z=10.169, P

Monoclonal antibody drugs that inhibit programmed death 1 (PD-1) or programmed death ligand 1 (PD-L1) have been widely used in esophageal cancer (EC) and yielded significant therapeutic responses. However, only a few patients obtain lasting clinical benefits due to primary or acquired drug resistance, and new treatment schemes are urgently needed. The tumor immune microenvironment is the main factor that affects patients' response to immunosuppressive agents. This article will discuss the role of immunosuppressive cells and non-cellular components in the immune process to provide ideas for the next research direction of EC.

Personalized news recommendation is an important technology to help users obtain the news information they are interested in and alleviate information overload. In recent years, with the development of information technology and society, personalized news recommendation has been increasingly widely studied, and has achieved remarkable success in improving the news reading experience of users. This paper aims to systematically summarize personalized news recommendation methods based on deep learning. Firstly, it introduces personalized news recommendation methods and analyzes their characteristics and influencing factors. Then, the overall framework of personalized news recommendation is given, and the personalized news recommendation methods based on deep learning are analyzed and summarized. On this basis, it focuses on personalized news recommendation methods based on graph structure learning, including user-news interaction graph, knowledge graph and social relationship graph. Finally, it analyzes the challenges of the current personalized news recommendation, discusses how to solve the problems of data sparsity, model interpretability, diversity of recommendation results and news privacy protection in personalized news recommendation system, and puts forward more specific and operable research ideas in the future research direction.

Objective With the rapid increase in construction projects in the western regions in recent years, the impact of seasonal freeze-thaw cycles in the high-altitude areas of western China has become more pronounced. Conducting research on the microscopic characteristics and strength degradation properties of rocks under freeze-thaw cycles is crucial for guiding engineering construction in these cold, high-altitude regions. Methods To study the influence of freeze-thaw cycles on rock structure and mechanical properties, we collected diorite samples from a tunnel in the Kangding area and examined the effects of freeze-thaw cycles on their microstructure and mechanical characteristics. Firstly, thin rock sections were observed under a polarizing microscope to obtain mineral compositions and microstructures. Then, CT scanning technology was used to scan the granite samples after freeze-thaw cycles, and the scanned layers were binarized using threshold segmentation. The scanning images of different layers were binarized using threshold segmentation, and high-resolution 3D data and images of the internal and external structures of the samples were obtained by stacking the binary image layers. Fractal theory was applied to calculate the box-counting dimension of the images and quantitatively assess their complexity. This analysis allowed us to examine the evolution and distribution characteristics of the internal structure of granite under freeze-thaw cycles. Results Under a polarizing microscope, the rock exhibits a block-like structure with a patchy, coarse-grained, and unequal-grained granite texture, with locally visible metasomatic worm structures. The main phenocryst minerals are alkaline feldspar. Other minerals range in size from 0.25 to 4.0 mm and primarily include quartz, plagioclase, and alkaline feldspar. Secondary minerals include biotite and epidote, while accessory minerals comprise apatite, zircon, and pyrite. Microscopically, the rock is identified as porphyritic, coarse-grained, and unequal-grained biotite diorite granite. Freeze-thaw cycles were applied to the granite samples in the laboratory to study the strength evolution and explore the relationship between structural evolution and strength. The results indicate that the freeze-thaw cycle effect leads to an overall increase in the internal porosity of the granite's microstructure, though the rock's permeability changes minimally, with an increase of only 0.003×10−3 μm2. The internal pore development is uneven, primarily due to the emergence of new micropores, causing changes in the overall structure of the sample. After freeze-thaw cycles, the complexity of the internal structure of the rock decreases, but the overall integrity remains good, with the fractal dimension staying at a high level. Fractal analysis shows that 20 freeze-thaw cycles do not cause significant changes in the structural complexity of granite. However, the overall mechanical properties of the sample decline, viscosity increases, and long-term strength shows significant attenuation, raising the strain threshold for entering the creep test stage. Conclusion When evaluating the safety of rocks with dense primary structures, considering only their structure may lead to deviations from the actual situation. It is essential to combine necessary strength indicators for a comprehensive evaluation. After undergoing freeze-thaw cycles, rocks tend to exhibit more significant deformation while maintaining lower strength. Therefore, appropriate treatments are required for construction in high-altitude areas. [ Significance ] This study provides a reference for applying fractal theory to the evolution of rock microstructure and the relationship between rock microstructure and strength evolution. It also offers valuable guidance for engineering construction in high-altitude and cold regions.

With the rise of artificial intelligence medical device (AIMD) industry, it is urgent for stakeholders to establish consensus on the definition and concepts of AIMD quality evaluation, so as to further support the development of standards and guidelines. To break through industry bottleneck, the National Medical Products Administration (NMPA) published YY/T 1833.1-2022 Artificial Intelligence Medical Device- Quality Requirements and Evaluation- Part 1: Terminology in 2022, which provides unified terminology. This standard is divided into five chapters, including a total of 158 terms that cover basic technology, data set, quality characteristics, quality evaluation and application scenario. This article introduces the general overview, the drafting history and explains its significance, with the aim of guiding the development of artificial intelligence medical device industry.

Datasets, as an important resource for artificial intelligence medical device industry, have been placed under medical device supervision. National Medical Products Administration (NMPA) has published a sectoral standard named YY/T 1833.2-2022 Artificial Intelligence Medical Device-Quality Requirements and Evaluation-Part 2: General Requirement for Datasets to guide dataset quality evaluation. This standard describes dataset requirements for documentation and quality measures, proposes evaluation methods, and helps dataset producers enhance quality control from the source. It would benefit clinical agencies in dataset construction and better meet industry need. This article introduces the background and key points of the standard, in order to better guide the applications in artificial intelligence medical device industry.

The analysis of transient voltage and current characteristics of DPFC （distributed power flow controller） under lightning strikes is an essential consideration in its design and operational management. Firstly， the structure and operational principles of DPFC are introduced， and simulation models are respectively constructed for two scenarios： a centralized arrangement of DPFC sub-modules in substations and a decentralized arrangement along transmission lines. Subsequently， the electromagnetic transient characteristics of DPFC are simulated and analyzed in the case of back strikes on the conductors and circling strikes on the transmission line， and the overvoltage and overcurrent levels at critical positions of DPFC during lightning strikes are thereby obtained. Finally， the differences in overvoltage and overcurrent between the centralized and decentralized arrangement of DPFC sub-modules are compared and analyzed in the case of back strikes and circling strikes. It is concluded that when lightning strikes the lightning conductor， the overvoltage to earth and the overvoltage at the submodule port of the centrally arranged DPFC are larger than the results of the decentralized arrangement； the overcurrents of the submodule of the centrally arranged DPFC and the arrester are smaller than the results of the decentralized arrangement.

The steering trapezoid of automobiles can be seen as a link mechanism. It controls the motions of the tyres and influences on the steering Ackermann rate, steering gear ratio, rack force, and so on. A list of steering trapezoid's design parameters based on the benchmark data is given in the study. Front steering trapezoid can be replaced of rear steering trapezoid in the same front suspension system that is proved in this study. The steering trapezoid of a hybrid power automobile is designed taking advantages of Catia V5 parameterized model and front suspension motion model based on Adams. Low cost and low design risk come true through the design method of the steering trapezoid.

The training of medical imaging emphasizes the combination of theory and practice. This study discusses the necessity and feasibility of sketch course combined with three-dimensional reconstruction in medical imaging teaching, as well as the advantages and basic requirements of sketch course.

In this study, Fusarium graminearum was identified as the pathogen causing the decay of ginger from Jiangshan, Zhejiang Province during postharvest storage by tissue separation, morphological characterization, ribosomal DNA internal transcribed spacer (rDNA-ITS) sequence analysis and phylogenetic tree construction. By using solid phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS), the changes of volatile flavor in fresh ginger during infection with F. graminearum postharvest were studied through the determination of volatile flavor compounds in healthy tissues, the junction between healthy and diseased tissues, and diseased tissues of fresh ginger. Principal component analysis (PCA) was used to evaluate the flavor quality of fresh ginger during postharvest disease development. The results showed that a total of 58 volatile flavor substances were detected in ginger, of which 40 substances were detected in healthy tissues, 35 substances in the junction of diseased and healthy tissues, and 39 substances in diseased tissues. These volatile flavor substances mainly included olefins, alcohols, esters, aldehydes, and ketones. Olefin compounds were the major components contributing to fresh ginger flavor, accounting for more than 80% of all flavor compounds. During disease development, the content of olefin flavor compounds increased significantly (P < 0.05), and the sesquiterpene components zingiberene and β-sesquiterpene were detected in different parts of fresh ginger and their contents continued to increase, which could be used as the indexes for determining whether or not fresh ginger is infected with F. graminearum after harvest. This may be due to the activation of the resistance mechanism of pathogen infected fresh ginger and consequent release of sesquiterpene components in large quantities.

A nonlinear finite element model of high head expansion water seal is established to simulate the mechanical performance and deformation characteristics of the rubber material during the water sealing process. The influence of back pressure, reservoir water pressure and other parameters on sealing performance of the expansion water seal are further investigated. Firstly, the uniaxial tension compression and pure shear test date of rubber material are used to curve fitting and the Mooney-Rivlin model parameters based on the least square method. The APDL programming language in ANSYS is used to determine the contact state of steel head and apply the cyclic loads from lateral water pressure. Secondly, the influence of the Mooney-Rivlin model with different number of parameters on the accuracy of the simulation is analyzed by numerical examples. The validity of the simulation is verified by comparing with the model experiment. Finally, the parametric studies are presented to explore variations of free expansion, contact stress and steel head offset with back pressure, reservoir water pressure and the distance between panel and pressing plate in different working stages. [ABSTRACT FROM AUTHOR]

A series of processable and high-temperature resistant polyimide resins terminated with 4-phenylethynyl phthalic anhydride were synthesized by PMR (for in situ polymerization of monomer reactants) using isopropyl alcohol as esterifying agent. The resin solution stored at room temperature for sixteen weeks has no solid precipitation, and the viscosity of the solution does not change significantly, which shows good storage stability at room temperature. The minimum melt viscosity of the imide oligomers is less than 300 Pa·s, which is suitable for compression moulding or autoclaved process. The cured polyimides exhibit extremely high glass transition temperatures (Tg) up to 462℃. The flexural strength and modulus of T300/PMR-PE-2 carbon fiber composite are 963 MPa and 53 GPa, respectively. The inter-laminar shear strength of the composite is 56 MPa. Moreover, the composite can maintain no lower than 66% of their room temperature mechanical properties at 300℃. After isothermal aging in air atmosphere for 500 h at 300℃, the mass loss of the composite is only 0.96%, meanwhile, the composite retention rate maintains 72% of its room temperature flexural strength and 98% of its room temperature inter-laminar shear strength, which demonstrates its excellent thermal-oxidative aging resistance.

As a biometric technology, gait recognition is usually considered a retrieval task in real life. However, because of the small scale of the existing radar gait recognition dataset, the current studies mainly focus on classification tasks and only consider the situation of a single walking view and the same wearing condition, limiting the practical application of radar-based gait recognition. This paper provides a radar gait recognition dataset under multi-view and multi-wearing conditions; the dataset uses millimeter-wave radar as a sensor to collect the time-frequency spectrogram data of 121 subjects walking along views under multiple wearing conditions. Eight views were collected for each subject, and ten sets were collected for each view. Six of the ten sets are dressed normally, two are dressed in coats, and the last two are carrying bags. Meanwhile, this paper proposes a method for radar gait recognition based on retrieval tasks. Experiments are conducted on this dataset, and the experimental results can be used as a benchmark to facilitate further research by related scholars on this dataset.

Fatigue failure and stress damage are the main damage forms of marine risers.To study the variation rule of surface magnetic field signals of X80 steel during tensile fatigue process under geomagnetic excitation, the fatigue tensile test of X80 steel specimens under typical working conditions was carried out with an MTS810 250 fatigue tensile testing machine. During the experiment, the variation of magnetic field on the surface of the tensile specimen was monitored by a magnetic memory sensor, the fatigue failure of the specimen was observed by a handheld microscope, and the morphology of the fracture was analyzed with the help of scanning electron microscope(SEM).The results show that the magnetic memory is sensitive to the tensile fatigue damage. Thus, the characteristic parameters of magnetic memory detection for tensile fatigue damage of X80 steel were proposed, which took the extreme value of magnetic memory signal with background removed HE(X) and the line slope of the extreme value of tangential gradient signal SK(X) as the eigenvalues. As a result,zero crossing phenomena occur to HE(X) and SK(X) in the stage of crack initiation. The acceleration of HE(X) and SK(X) speeds up with the increase of the fatigue cycle, which is consistent with the crack growth law during the fatigue process. Generally, HE(X) and SK(X)can reflect the fatigue failure process of the specimen, and they can be used to monitor the fatigue damage of marine risers. This research results could provide a reference for the field application of the magnetic memory detection method in the fatigue damage detection of marine risers.

Objective·To identify the causative gene and mutations and describe the clinical traits in a Chinese diabetes pedigree suspected of Wolfram syndrome.Methods·A total of 12 subjects from one family were included. The proband was admitted to the Department of Endocrinology, The First Affiliated Hospital of Xinxiang Medical University, for the first time in May 2013. Then he visited the hospital for follow-up in July 2022 and in April 2023, respectively. The other members of this family included the proband′s sister, father, mother, paternal grandfather, paternal grandmother, uncle, aunt, as well as maternal grandfather, maternal grandmother, and two brothers of the proband′s mother. Clinical data of all subjects were collected. The whole exome sequencing was used to screen the pathogenic genes and mutation sites of six members of the family, and Sanger sequencing was used to verify the above results. Effects of the mutation of the pathogenic gene WFS1 in Wolfram syndrome on the function of the wolframin protein were evaluated by bioinformatics softwares, including CADD, DANN, MetaSVM, Polyphen-2, SIFT and M-CAP. The three-dimensional structures of wild-type and mutant wolframin proteins were constructed with Swiss-Model software, and visualized with PyMOL software. Cluster Omega software was used for evaluating species conservation of WFS1 gene mutation sites. JNetPRED software was used for online prediction of wolframin protein secondary structure.Results·The proband and his sister both carried R558H and S411Cfs*131 mutations, two compound heterozygous mutations of the Wolfram syndrome pathogenic gene WFS1. The proband′s father and parental grandfather both carried the R558H mutation, while the proband′s mother and maternal grandfather both carried the S411Cfs*131 mutation. The R558H mutation was a rare missense mutation, and the S411Cfs*131 mutation was a novel frameshift mutation. Bioinformatics analysis softwares predicted that the R558H mutation located in the α-helical structure of the wolframin protein. This mutation was a damage mutation and the amino acid sequence of the mutation region was highly conservative among 12 species with varying degrees of evolution, including humans.Conclusion·Two causative mutations of WFS1 gene are identified in a Chinese diabetes pedigree by whole exome sequencing. The study supplements the existing genotype and phenotype profiles of Wolfram syndrome, which can realize early diagnosis of diabetes pedigrees and help in performing timely follow-up of patients, so as to achieve early intervention and treatment of this disease.

Silicone rubbers are extensively used in high-end equipment in ionizing radiation environments because of their satisfactory elasticity, thermostability, high/low-temperature resistance, and aging resistance characteristics. Experimental studies and theoretical calculations are of equal importance because of their complicated radiolytic behaviors and mechanisms. This paper reviews the progress of simulation studies on radiation-aged silicone rubber. Many examples are listed and summarized to reveal their highlights in solving practical issues from the perspective of multiscale simulations, where mutual validation and verification of experiments and simulations are also discussed. Based on the characteristics of the spatiotemporal scale of the modeling methods, this paper is organized into the following six sections. Frequently adopted simulation methods include quantum electrodynamics, density functional theory, quantum molecular dynamics, reactive molecular dynamics, traditional molecular dynamics, and constitutive models and finite-element simulations. These methods are strongly associated with research demands, including the process and mechanism of interaction of silicone with radiation, evolution law and mechanism of system damage, and the structure–property relationship. Some studies have involved several modeling methods that are compiled into the most featured sections. This review presents a wide range of simulation studies on silicone rubber, outlining its research status and the current challenges for the academic and engineering community. This review provides novel ideas and knowledge bases for experimental studies and solutions to engineering problems.

Maritime unmanned system are crucial for future intelligent and unmanned warfare. They have become a new height of competition in the maritime domain and will play an increasingly important role in national defense security. Considering the development demand for national intelligence and unmanned strategies, the study analyzes the development status of maritime unmanned systems and corresponding technologies in China and abroad from the aspects of strategic planning and conceptual guidance, technological research and equipment development, and system demonstration and capability verification. The challenges and trends for the development of maritime unmanned systems are summarized and key technical challenges are proposed. Moreover, development pathways of maritime unmanned systems in key directions are explored and countermeasures to promote the sustained, steady, and rapid development of maritime unmanned systems are recommended from the perspectives of overall thinking, system composition, equipment development, and technology breakthroughs.

Objective To investigate the overall state of the glycemic control in children with type 1 diabetes mellitus (T1DM) in a single center and analyze the related factors. Methods This cross sectional clinical based research was conducted among patients under 18 years old diagnosed with type 1 diabetes (the duration of diabetes>3 months) from the Diabetes Clinic of Beijing Children's Hospital from January 2015 to December 2019. The patients were required to receive a follow up every 3 months. The follow up data of the same patient were collected once a year. Glycosylated hemoglobin (HbA1c) was taken as the main research index (the selection principle was the median glycosylated hemoglobin per year). Demographic data included age at onset and at follow up, sex, duration of diabetes, years of follow up. In addition, clinical information on weight, height, modalities of insulin treatment (number of injections or pump therapy), the frequency of self monitoring of blood glucose (SMBG) per day or using of continuous glucose monitoring (CGM)/flash glucose monitoring (FGM) were collected. According to the years of follow-up, the patients were divided into 5 groups. According to the HbA1c control target (7.0%), the patients were divided into the good-control group (HbA1c<7.0%) and the poor-control group (HbA1c ≥7.0%). According to the age of the patients, they were divided into three groups (<5 years old group, 5 to 10 years old group and>10 years old group). The general situation of blood glucose control from 2015 to 2019 was compared by groups, and the related factors were analyzed by linear regression and two level logistic regression. Results A total of 1 976 patients with T1DM were collected (2015 n=362, 2016 n=410, 2017 n=415, 2018 n=384, 2019 n=405), the age was 10.09 (7.18, 12.85) years old; the duration of diabetes was 1.94 (0.88, 3.86) years, 49.5% (978/1 976) were male. There was no significant difference in age, sex and duration of disease among each groups (P>0.05), and comparable. HbA1c decreased from 7.4% (6.7%, 8.3%) in 2015 to 6.8% (6.1%, 7.6%) in 2019 (P< 0.01). The rate of achieved A1C target increased year by year [34.5% (125/362), 42.0% (172/410), 47.0% (195/415), 55.2% (212/384) and 56.3% (228/405), respectively], and the difference was statistically significant (Z=7.02, P<0.01). The HbA1C was positively correlated with age and duration of disease (r=0.095, 0.170 respectively, P<0.01). Logistic regression analysis showed that older of age, longer duration of disease and less frequency of daily blood glucose monitoring were the risk factors of failing to achieve HbA1c target. Conclusions From 2015 to 2019, HbA1c in children with T1DM has decreased year by year, and the rate of achieved A1C target has increased year by year, and it has increased by 1.63 times in 2019 compared with 2015. The increase in the use of CGM/FGM is the main factor to improve blood glucose control. [ABSTRACT FROM AUTHOR]

The accurate division of the disturbance space of abandoned mine methane(AMM) reservoir is an important basis for the evaluation, development and utilization of AMM resources. In this paper, taking the No. 2 coal 12501 working face of Tunlan Mine in the Xishan mining area of Shanxi as an example, numerical simulation of stress field, numerical simulation of fracture field and physical similarity simulation are used. The distribution law of stress field and fracture field during the mining process and after the goaf is stabilized is comprehensively studied. The research results show that the physical similarity simulation and the numerical simulation have a high degree of agreement. Combining the above three methods, the CBM disturbance reservoir space in the abandoned working face 12501 is finally divided into floor fracture area, recompaction area, gas conduction fracture area and bearing fracture area. The floor fissure area is located just below the working face in the coal seam. The overall mining fissure development area presents an inverted trapezoidal platform with the bottom surface close to the mined coal seam. The numerical simulation results of the fissure field show that its vertical depth is 22.3 m, Its depth is 5.58 times the thickness of the coal mined. The pressure-bearing area is located in the unexploited coal reservoir around the working face. It extends 70 m outward from the boundary of the working face inclination and 100 m from the boundary of the working face strike. The numerical simulation results show that the peak value of vertical stress of coal reservoir in the pressure bearing zone is much larger than the stress value of the original state of the coal seam, but smaller than the average compressive strength of the coal sample in the vertical seam. The main part of the gas-conducting fissure area is located at the edge of the coal seam working face. The bottom is a rock caving zone with a height of about 13.2 m, and the upper part of the caving zone is a rock stratum fault zone with a height of about 33.6 m. The vertical cracks in the fault zone continue to expand and penetrate through. Separation cracks. The overall shape of the gas-conducting fracture area is a trapezoidal platform, Its height is 11.7 times the thickness of the coal mined.. The main body of the recompaction area is distributed in the middle part of the goaf of the mining face, with a dip width of 110 m and a strike length of 1 268 m. This area is mainly composed of curved and caving overlying rocks, and the overall shape is a trapezoidal platform, which is located inside the gas-conducting fracture area. The gas-conducting fracture area is a favorable area for the development of legacy coalbed methane resources.

To study the energy evolution of rocks under uniaxial compression, uniaxial compression and uniaxial step loading and unloading tests were performed on granite, sandstone, and coal, and the stress-strain curves under different conditions were obtained. The total energy density, elastic energy density and dissipation energy density for the whole process of rock specimens under different conditions were obtained by using the integral and formula. The energy evolution characteristics of rock specimens before and after the peak were analyzed, and the relationship between elastic energy density and total energy density under uniaxial compression were investigated. The results show that the outer envelope of the uniaxial step loading and unloading stress-strain curves have the same trend as the uniaxial compression curves, and the overall deviation exists to a certain extent, and the greater the density of the rock, the smaller the deviation is. The elastic energy density and total energy density of the rock specimens satisfy the linear energy storage law under uniaxial compression and uniaxial step loading and unloading. The energy storage limit of uniaxial compression and uniaxial step loading and unloading, which are almost equal, is obtained by using the linear energy storage law, and the greater the strength of the rock is, the greater the energy storage limit is.

Porous layered g-C3N4 was selected as base material via direct calcination method to synthesize g-C3N4/CeO2/BiOBr ternary composite photocatalytic materials with heterogeneous structure, while CeO2/BiOBr composites were introduced by ultrasonic stirring method. The composition, structure and optical properties of g-C3N4/CeO2/BiOBr were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, UV-Vis DRS and photoluminescence analysis, and so on. The results show that the g-C3N4/CeO2/BiOBr has sandwich layered stacking structure, good interface contact structure and excellent light response performance due to the uniform phase distribution and high degree of crystallization. When the molar fraction of Ce∶Bi is 1∶1 and the mass fraction of g-C3N4 is 15%, the obtained three-phase composite shows the highest photocatalytic degradation property for RhB. The degradation rate for RhB is 99%, which is 86 times that of pure CeO2 and 3 times that of pure BiOBr. In addition, the composite has good stability with the RhB degradation efficiency of 89% after four cycles.

Distributed power flow controller （DPFC） can improve power flow distribution in the power grid and solve the problem of power flow section excess. Based on the topology structure and operation principle of DPFC and with the backing of the world’s first 220 kV DPFC demonstration project， a distributed power flow control simulation model is established. The cases of distributed power flow controllers centrally installed in substations and dispersedly installed in transmission lines are considered， respectively. The overvoltage and overcurrent levels of DPFC key nodes in the case of short-circuit faults on the transmission lines are simulated. Moreover， it is analyzed how fault location influences the DPFC's overvoltage and overcurrent. The calculation results in this paper can provide a reference for DPFC insulation coordination in engineering practice.

Objective: In order to evaluate the difference of characteristic flavor intensity between different times of cyclic stewed beef. Methods: The volatile flavor compounds in circulating stewed beef were determined by solid phase microextraction-gas chromatography-mass spectrometry （SPME-GC-MS）, and the key flavors with important contribution were screened out according to the relative odor activity value. The flavor substances contributed by circulating stewed beef were analyzed by principal component analysis, the flavor intensity evaluation model of cyclic stewed beef was established, and the comprehensive evaluation of cyclic stewed beef was carried out combined with sensory evaluation. Results: The seven key flavourings were n-hexanal, undecanal, nonanal, n-hexanol, 3-methylpentane, cineole and anethole. The results showed that the contribution rates of the first to third principal components obtained by principal component analysis were 52.40%, 25.64% and 12.95% respectively, and the cumulative contribution rate was 90.98%, which could represent the main information of volatile flavor substances in cyclic stewed beef. The correlation coefficient between the characteristic flavor intensity of the model and the sensory score was 0.90（P＜0.05）. Conclusion: The model can be applied to the flavor evaluation of cyclic stewed beef.

Gut microbiota is indispensable for the maintenance of human immune homeostasis. Dysbiosis and translocation of gut microbes as well as aberrance of microbiome metabolites, which are commonly seen in many autoimmune diseases, are suggested to participate in the breakdown of immune tolerance and the excessive inflammatory responses. The involved mechanisms include immune equilibrium skewing, molecular mimicry, bystander activation and epitope spreading, which contributes to the initiation and progression of autoimmune diseases. In addition, the microbial biotransformation of antirheumatic drugs help determine the bioactivity and toxicity of these drugs. Herein, gut microbiota-based intervention may shed light on developing novel strategies for prophylaxis and treatment of autoimmune diseases. In this review, recent advances in exploring the potential pathogenic role of gut microbiota in autoimmunity are summarized and the prospect of applying microbiota-based intervention in systemic autoimmune diseases is addressed.

Objective: To purify and comprehensive identify αS1-casein from bovine caseins and prepare rabbit polyclonal antibody against αS1-casein. Method: DEAE Sepharose Fast Flow anion exchange chromatography was used to separate and purify αS1-casein. The physicochemical property (isoelectric point and protein content), immunological technique and mass spectrometry were used to comprehensively identify αS1-casein. Then the αS1-casein was obtained by dialysis and lyophilization, polyclonal antibody was prepared by immunizing New Zealand white rabbit with the purified αS1-casein, and the specificity of polyclonal antibody was analyzed. Result: Among the four kinds of caseins, αS1-casein had the latest peak time, the largest peak area in anion exchange chromatography and the highest position in the electrophoretic diagram. Finally, the purity of αS1-casein was 94.26%, and the yield was 27.19%. The titers of sera from two rabbits inoculated with purified αS1-casein for five times reached 1280000 and 320000, respectively. In addition to the slight cross reaction with soybean protein (

The commonly used analytical techniques for the detection of primary aromatic amines (PAAs) in food contact materials (FCMs) include gas chromatography-mass spectrometry (GC-MS), capillary electrophoresis (CE), high-performance liquid chromatography (HPLC), HPLC-tandem mass spectrometry (HPLC-MS/MS), HPLC-high resolution mass spectrometry (HPLC-HRMS), etc. The migration of PAAs was determined in various types of FCMs using the above-mentioned techniques, such as laminated flexible packaging materials, polyamide cookware, plastic bags, and napkins. For the migration experiment, those methods generally adopted a single contact time and contact temperature, which may deviate from the migration amount occurred in the actualapplication. In contrast, European Union Directive (EU) No 10/2011 (annex Ⅲ) specified the time/temperature conditions for migration test of food simulants and plastics. Therefore, it is reliable to detect the migration of PAAs based on the expected food contact situations including food nature, contact time, and contact temperature for different types of FCMs. In this study, a method of high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed for the determination of the migration of 33 PAAs from FCMs and articles. 20% ethanol, 50% ethanol and 3% acetic acid solutions were used as food simulant solutions to simulate the hydrophilic, lipophilic and acidic food. For FCMs, such as disposable paper cups, colored plastic knives and forks, food bags, plastic milk bottles, pacifiers, etc., they were cut into rectangles with the side lengths of 0.5-1.0 cm. FCM samples of 5 g were weighed in a volumetric flask, and food simulant immersion solution of 100 mL was added. According to the physiochemical properties of the main ingredients in food and whether the FCMs and articles are expected to repeat contact with food, the conditions of food simulant solution and migration experiments were optimized. Chromatographic separation of the migration solution was performed on a Kinetex F5 column by a gradient elution of 0.05% formic acid-methanol solution. The detection was completed in positive electrospray ionization (ESI+) and scheduled multiple reaction monitoring (MRM) mode. The external standard method was used for quantitation. The absolute matrix effects (AMEs) of the 33 PAAs in the migration solution of 20% ethanol, 50% ethanol, and 3% acetic acid (pH 7.0) were 86.1%-97.3%, 88.7%-104.0%, and 62.7%-81.3%, respectively. Good linearity (r>0.99) was obtained within their respective linear ranges. The limits of detection (LODs) and quantitation (LOQs) were 0.02-1.04 μg/kg and 0.07-3.26 μg/kg, respectively. This method is sensitive, reliable, and suitable for the accurate determination of the migration of PAAs from FCMs and articles.

Powder extrusion printing (PEP) is an additive manufacturing (AM) technology based on the combination of traditional metal injection molding and 3D printing, which has the advantages of wide range of printable materials and low cost. The PEP process of WC-13Co cemented carbide was studied, including the development and properties of thermoplastic printing materials, such as the dispersity, rheology and formability. The effects of debinding and sintering process on the microstructure and mechanical properties of the final parts were also investigated. The results show that the specialized binder for PEP of cemented carbides has been prepared successfully. EDS analysis demonstrates that the binder is uniformly dispersed in the green body. The binder can be effectively and totally removed from the green body by two-step debinding process. In combination with vacuum sintering at 1450 ℃ for 60 min, high performance of cemented carbide sample with the shrinkage rate of 17.8%, uniform distribution of WC grain size, and Vickers hardness of 1410HV30 is successfully fabricated. The result confirms that the PEP technology can be applied to prepare cemented carbide materials with high performance and controllable print size, which provides an effective technical route for additive manufacturing of cemented carbide.

The era of digital intelligence offers new opportunities for the development of social computing and social intelligence.Cross-disciplinary fusion shall be a critical approach for its deep development.This paper elaborates the connotation and denotation of social computing, discusses the paradigm shift of social computing research, and the general development of social computing and social intelligence.Next, it looks forward to the social computing and social intelligence in the era of digital intelligence, and proposes three pillars for constructinga social intelligence system based on the new infrastructure.The construction of such an intelligent system is mainly composed by three components, including the construction of large-scale high-velocity data intelligence, the integration of multi-scale flexible spatial intelligence, and the formation of complex adaptive social intelligence.There is a level progression from data intelligence to social intelligence, in which data, computing and society are entangled.As such, computing science, data science, spatial science, complex science and social science are requested to interact from both theoretical and methodological perspectives.With the rapid update of digital-intelligent technologies and their penetration into the whole social-economic system, social computing and social intelligence is bound to seek breakthrough and deep development in the interdisciplinary cross-integration.

China’s government has built a certain scale of charging station network. To address the problems of low charging station network utilization, the existence of a large number of redundant charging stations, and the diffi-culty of charging, this paper proposes a data-driven charging station network optimization approach. Firstly, this paper simulates the charging behavior of EV (electric vehicle), establishes queuing systems for charging stations in different time stamps, and then estimates the arrival rates among charging stations. On this basis, the spatial characteristics of urban EV charging behavior are analyzed, which is used to explore the urban EV charging hotspots. Then, the interactions among competitive dependencies, geographic features and user charging preferences among charging stations are modeled, and a scoring function is proposed to assess the usage benefit of charging station in the network. Lastly, a charging station network optimization model which aims at maximizing the usage benefit of charging station network is developed, and a heuristic network expansion algorithm based on charging hotspots is also presented to solve the model, and thus the optimal charging station network layout can be obtained. Taking a typical urban area as an example to conduct experiments, the experimental results demonstrate that the method proposed in this paper can not only improve charging station utilization while eliminating redundant stations, but also identify charging station network congestion areas, which can provide decision support for government planning departments to solve the charging difficulty.

Power swamping is one of the important ways to replenish the energy of electric vehicles. Based on the relationship between battery degradation and charging speed， the paper takes battery swamping stations containing photovoltaics as the research object to design a variable-speed charging mechanism that takes account of the prediction of PV and traffic， and it establishes an economic revenue model of the swamping station considering the variable-speed charging mechanism. The model can flexibly adjust the charging speed of batteries according to the traffic flow and light intensity and optimize the power output and charging power distribution of various power sources. The validity of the model is verified by examples， and the results show that compared with the traditional constant power charging model， the proposed model can utilize PV resources more efficiently， reduce the power purchase cost of the swamping stations， lower the average charging speed of batteries and reduce the cost of battery loss， maximizing the economic benefits of the system.

BackgroundCurrently, the destructive puncture manometry method is used to measure helium pressure inside fuel rods. However, this method is expensive and does not guarantee 100% coverage. Hence the non-destructive testing (NDT) equipment is introduced for non-destructive measurement of helium pressure inside fuel rods.PurposeThis study aims to analyze the reliability of NDT testing method for the measurement of helium pressure inside fuel rods.MethodsThree standard rods with helium pressure values of 0.98 MPa, 1.76 MPa, 2.45 MPa, respectively, were selected for experimental test. The experimental fuel rods were first used to obtain the results comparison of heat transfer method and puncture manometry, then the control variates were employed to control the fuel rod temperature, the time interval of a single measurement, and the ambient temperature respectively, so as to determine influencing factors in the NDT method. Finally, reliability analysis of NDT method was performed according to experimental results.ResultsThe results of the NDT method are consistent with that of the puncture manometry method at a temperature range of 24~30 ºC with less than 0.05 MPa deviation. Minimum repeat measurement time interval for NDT measuring helium pressure of the same standard rod or fuel rod is 2 min.ConclusionsThe NDT method for measuring the helium pressure of fuel rods is reliable, and the measurement results are stable in different environmental conditions.

In order to realize the safety, high efficiency and high recovery rate mining of 9-13 m thickness hard coal seam in Jinjitan Coal Mine, the top coal recovery rate and coal wall stability of different cutting heights are analyzed by theoretical analysis and numerical simulation. Based on the corresponding relationship between top coal recovery rate, coal wall stability and cutting height, a super large mining height and small mining and drawing ratio technology which based on mining and supplemented by releasing is proposed. The ZFY21000/35.5/70D two pillar shield hydraulic support with super large mining height is developed. Based on the optimization design of anti impact column and high-efficiency caving mechanism, the problems of easy impact of super high mining height fully mechanized top coal caving face, easy rib spalling of coal wall and easy arching of hard coal are solved. Fully mechanized top coal caving mining with super high mining height and small mining and caving ratio is an effective way to improve recovery rate and realize high yield and high efficiency of extra thick hard coal.

The polarization switching properties of P(VDF-TrFE) ultrathin films with different storage periods were measured. The dependence of polarization properties on temperature and storage period was investigated. The experimental results suggest that the relative remanent polarization (Pr/Pr0) remains on a relatively high level of 0.70 at 60℃, 106 polarzation swiching test, even to the ultrathin film capacitors stored in atmosphere for five months. The time stability model of polarization switching is predicted by the evolution of polarization switching with the number of electric field cycles. Moreover, when the changes of the molecular chain are simulated by different storage periods and testing temperatures, an inhibited hydrogen fluoride (HF) gas formation scheme in the capacitors was proposed. This work further validated the time stability model and microscopic dynamics associated with trapped charge. These results provide an effective method for designing an optimum protocol for flexible electronic devices based on P(VDF-TrFE) copolymer ultrathin films.

The establishment of a network information platform for a centralized procurement system for laboratory animals in colleges and universities has made the inventory supply and settlement management of laboratory animals centers more systematic, convenient, and scientific. The application of this system in the Laboratory Animals Department of Capital Medical University was examined, and the results showed that the establishment of a clear centralized procurement management module could greatly save labor and time, improve the work efficiency, and standardize procurement and supply personnel. The findings strongly suggested that the network informatization of the centralized procurement system of laboratory animals in colleges and universities is necessary.

In recent years, convolutional neural network (CNN) has made remarkable achievements in many applications in the field of image analysis with its powerful ability of feature extraction and expression. However, the continuous improvement of CNN performance is almost entirely due to the deeper and larger network model. In this case, the deployment of a complete CNN often requires huge memory overhead and high-performance computing units (such as GPU) support. However, there are limitations in the wide application of CNN in embedded devices with limited computing resources and mobile terminals with high real-time requirements. Therefore, CNN urgently needs network lightweight. At present, the main ways to solve the above problems are knowledge distillation, network pruning, parameter quantization, low rank decomposition, lightweight network design, etc. This paper first introduces the basic structure and development process of convolutional neural network, and briefly describes and compares five typical basic methods of network compression. Then, the knowledge distillation methods are combed and summarized in detail, and the different methods are compared experimentally on the CIFAR data set. Furthermore, the current evaluation system of knowledge distillation methods is introduced. The comparative analysis and evaluation of many types of methods are given. Finally, the preliminary thinking on the future development of this technology is given.

This paper summarized the clinical experience of hospice care in a patient with end-stage gastrointestinal stromal tumor. The concept, knowledge and skills of hospice care were used to nurse a patient with gastrointestinal stromal tumor in the terminal stage, to help the patient to control symptoms, to provide comfortable care, to solve physical problems and to provide psychological support, spiritual care was provided through dignity therapy and meaning therapy; the patient's right to decision-making was respected, and pre-medical care plans were discussed and family members were instructed to participate effectively in the care. (本文总结1例胃肠道间质瘤终末期患者安宁疗护的临床经验。 运用安宁疗护的理念、知识和技能, 对1例胃肠道间质瘤终末期患者进行护理, 帮助患者症状控制, 提供舒适照护, 解决躯体问题, 提供心理支持; 评估灵性需求, 采取尊严疗法和意义疗法, 提供灵性照护; 尊重患者的自主决策权, 谈论预先医疗照护计划, 指导家属有效参与护理。)

Objective To study the qualitative analysis strategy for unknown synthetic cannabinoid in the suspicious herbal product when no reference substance is available. Methods The synthetic cannabinoid in herbal blend was extracted with methanol. The extract was concentrated by rotary evaporator and separated and purified by preparative liquid chromatography, to obtain high purity synthetic cannabinoid sample. Gas chromatography-mass spectrometry （GC-MS）, ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry （UPLC-QTOF-MS） and nuclear magnetic resonance （NMR） were used to determine the structure of the prepared compound. Results High purity unknown sample （10 mg） was obtained by preparative liquid chromatography. The sample was analyzed by GC-MS, UPLC-TOF-MS and NMR, and through spectrum analysis, the unknown synthetic cannabinoid was determined as 5F-EDMB-PICA. Conclusion The method to extract unknown synthetic cannabinoid from low content herbal products by preparative liquid chromatography was established, and the structure of the unknown sample was identified by comprehensive use of GC-MS, UPLC-QTOF-MS and NMR. The information will assist forensic laboratories in identifying this substance or other compounds with similar structures in their casework.