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Primary biliary cholangitis (PBC) is an autoimmune liver disease. During the diagnostic process, the patient’s autoimmune antibodies are routinely examined. Approximately 20% of PBC patients have positive anti-centromere antibody (ACA). We evaluated the clinical characteristics of ACA-positive and ACA-negative PBC patients to explain the differences in disease progression between these two groups. Retrospective data from 961 PBC patients at Beijing Youan Hospital from 2010 to 2019 were gathered and separated into two groups based on ACA positivity. We collected and evaluated clinical laboratory indices, gastroscopy findings, and liver function assessments. In addition, 60 liver biopsies were available for comparison between the 2 groups. Pathologists staged the histological findings using the Ludwig staging criteria and Nakanuma staging and grading. Immunohistochemical staining was also performed on liver biopsies to examine the expression of cytokeratin 7 (CK7) in the tissue. A synthesis of clinical indicators in the large cohort showed that alanine transaminase, aspartate aminotransferase, total bilirubin, IgG, white blood cell, and platelet were significantly lower in the ACA-positive group, indicating that the overall status of liver injury was more moderate in the ACA-positive group. Additionally, ACA-positive patients in the non-cirrhotic group were more likely to present with gastroesophageal varices related to portal hypertension. Finally, analysis of pathologic findings showed that parameters were mostly comparable in the two groups, but CK7 differed and was more significantly lower in the ACA-positive group in albumin–bilirubin grade 2 and 3 patients. In summary, we characterized and compared the clinical features of ACA-positive and ACA-negative PBC patients, corroborating previous studies on the relationship between ACA positivity and portal hypertension cross-sectionally. It suggested that gastroesophageal varices might happen in the earlier course of PBC natural progression in the ACA-positive group.

Objective The line impedance of urban rail transit catenary is significantly affected by many factors such as wire material, line length, surrounding environment, etc., resulting in significant impedance differences between different lines and different time periods. However, in the setting calculation process, assessments often rely on empirical formulas, leading to inaccurate setting values and affecting the selectivity and sensitivity of the protection device. When the system encounters a short-circuit fault, false operation or refusal to operate may occur, posing a great safety hazard. Therefore, it is particularly important to develop a device that can accurately test the short-circuit impedance of the catenary and perform setting calculations. Method A low-voltage short-circuit test method is proposed. The method sets a short-circuit point at the end of the catenary and realizes the measurement of short-circuit impedance by applying low-voltage direct current at the head end of the line. A high-precision dual-channel synchronous sampling technology is used to obtain accurate sampling values of voltage and current, and a new method for solving line impedance by exponential curve fitting is developed based on RL （Reinforcement Learning）simplified bilateral power supply model and combined with Newton iteration method. In addition, by developing a software that integrates parameter configuration and setting calculation, the catenary impedance measurement and setting calculation device is successfully integrated. Result & Conclusion This device is not only capable of parameter configuration and line impedance solving, but also can simulate and analyze the current changes at the short-circuit point. It can realize real-time measurement according to different lines and environmental conditions, significantly improves the accuracy of line impedance measurement, providing solid data support and important reference for setting calculations. The accuracy of line impedance calculation and short-circuit current results is verified through actual examples, thus the feasibility and effectiveness of this method is fully proved.

[Objective] To facilitate the achievement of China’s dual carbon goals and advance energy transitions tailored to local conditions across provinces, it is crucial to clarify the spatial differentiation patterns of energy transitions at the provincial level in China and identify the endogenous driving factors and their varying effects. [Methods] This study investigated 30 Chinese provinces, employing the proportion of clean energy in regional energy consumption as a metric. A multi-level analytical framework rooted in the sociotechnical systems perspective was constructed. The centroid model, ordinary least squares (OLS) method, and geographically and temporally weighted regression (GTWR) method were used to analyze the status and driving factors of China’s energy transition from 2000 to 2020. [Results] (1) Although the provinces exhibited differentiated progress in energy transitions, the regional disparities were gradually narrowing over time. (2) In terms of driving factors of regional energy transition,s resource endowments have been the core and dominant factor, particularly the underpinning role of hydropower resources and the locking-in and assurance role of fossil fuel endowments. However, regional carbon emission reduction pressures and innovation investments have become important driving forces for regional energy transition in the new period. (3) The driving factors and their effects on energy transitions in these provinces were characterized by significant spatial and temporal heterogeneity. Prior to 2012, clean energy production capacity and electricity imports from outside the region dominated almost all provinces. Post-2012, the influence of electricity imports weakened, while technological advancements gained greater influence. Spatially, resource endowments had a more significant impact on northern China, while economic development levels exerted a stronger influence on energy transitions in northwestern China. [Conclusion] As China’s energy transition accelerates, regional disparities are diminishing. This study recommends the construction of an integrated clean energy supply system of wind, light, water, and nuclear energy storage and transmission, supported by coal power; increasing technological investments to promote the efficient use of clean energy; and improving cross-regional energy allocation, thereby driving the transformation of energy structures and sustainable development.

Objective Shield tunneling may cause displacement and deformation of the nearby viaduct foundation and reduce its bearing capacity. Therefore, the deformation effect caused by shield tunnel closely side-passing viaduct foundation is studied based on an actual project. Method Relying on the project of Hefei Metro Line 5 in which the shield tunnel passes the pile foundation of the viaduct on the side, a three-dimensional numerical model is established to analyze the horizontal displacement,the longitudinal displacement and the settlement pattern of the pile foundation caused by shield construction. Result & Conclusion The research results show that the horizontal displacement at the pile bottom presents dynamic changes of leaving, approaching and leaving the tunnel. The horizontal displacement of the pile body is similar to a C shape flexture curve. The displacement increases first and then decreases along with the pile depths, and the extreme value is located at the pile depth of 9~10 m. The longitudinal displacement at the pile bottom （parallel to the tunnel axis） shows a bimodal curve. After the shield passing the pile foundation, the pile body undergoes longitudinal deformation in the opposite direction of the excavation. After the shield passing through the pile foundation for 12m and further, the horizontal displacement of the pile body in longitudinal direction rebounds, indicating that the influence of shield tunneling on the longitudinal deformation of the pile foundation is reversible to a certain extent. The settlement of the pile foundation presents a steep trend. The closer the pile foundation at the same side is to the tunnel, the greater the settlement. Moreover, the excavation of the far side tunnel will cause secondary settlement of the pile top. The maximum settlement occurs at the bottom of the No.4 pile foundation, and the settlement value is 4.94 mm.

BackgroundNon-suicidal self-injury （NSSI） behavior has become a major public health concern and can have significant implications for the physical and mental health of adolescents. Peer victimization is a risk factor for adolesents to have NSSI behavior， so exploring the relationship and underlying mechanism between peer victimization and NSSI functions will provide a promising strategy for the prevention and intervention of NSSI behavior.ObjectiveTo investigate the relationship between peer victimization and NSSI functions in adolescents with unipolar and bipolar depression， so as to provide references for the intervention of NSSI behavior in adolescent patients with unipolar and bipolar depression.MethodsUsing multi-stage stratified sampling， 940 adolescents with unipolar and bipolar depression who met the Diagnostic and Statistical Manual of Mental Disorders， fifth edition （DSM-5） criteria for bipolar depressive episodes or depressive disorders were selected from 14 psychiatric hospitals in China. All participations were assessed using Chinese version of the Functional Assessment of Self-Mutilation （C-FASM）， Multidimensional Peer-Victimization Scale （MPVS）， UCLA Loneliness Scale （UCLA-LS） and Patient Health Questionnaire-9 item （PHQ-9）. Pearson correlation coefficient was to assess the correlation among above scales， and the model fit and path coefficients for mediation were analyzed with model 4 in Process 4.0 for SPSS.ResultsA total of 698 （74.26%） adolescents with unipolar and bipolar depression completed the questionnaire survey. NSSI behavior was detected in 374 patients （53.58%）. Among adolescents with unipolar and bipolar depression and NSSI behavior， MPVS total score was positively correlated with the scores of NSSI emotion regulation function， attention-seeking function and social avoidance function in C-FASM （r=0.104， 0.130， 0.266， P

In order to solve the problem of efficient trajectory control of centimeter-scale robots with small size, a small jellyfish robot (JRT) is designed and developed, which is composed of an air chamber, a center of gravity adjustment device and a jellyfish-inspired thruster with a size of only ⌀6.8 cm × 5.3 cm. Its trajectory can be effectively controlled underwater through the coordination of the center of gravity adjustment device and jellyfish-inspired thruster. Underwater experiments verify the function of JRT swimming and hovering in the vertical direction, horizontal directional swimming, and horizontal ejection. By analyzing the force balance relationship and motion state data of JRT swimming in the vertical and horizontal directions, a trajectory control scheme is proposed. The speed of horizontal directional swimming can reach 1.7 cm/s, and the trajectory deviation is 0—3.4 cm, which shows that the JRT has a good trajectory control ability and is expected to be applied in underwater resource exploration, environmental monitoring, and other fields.

The generation efficiency of data products depends on both the computational efficiency and the startup efficiency of algorithms. In meteorological operations, algorithms are typically data-driven, meaning they are initiated immediately upon data arrival to accelerate the generation time of data products. Therefore, data-driven meteorological services urgently require an efficient task scheduling framework to achieve the goal of starting and running algorithms as soon as data arrive, and to improve the generation efficiency of meteorological data products. CMA Big Data and Cloud Platform, referred to as Tianqing and led by National Meteorological Information Center, began nationwide business operations in December 2021. The data processing line (DPL), as the core function of Tianqing, enables the unified management and centralized scheduling of meteorological algorithms. DPL has established various task scheduling capabilities, including timer-triggered scheduling, sequential scheduling, data-arrival scheduling, and manual scheduling. Among these methods, data-arrival scheduling based on data reporting status enables the algorithm to start immediately after data reporting, greatly improving the startup time of meteorological algorithms and the generation time of meteorological data products.Core functions of data-arrival scheduling include data state awareness components, task scheduling execution components, task scheduling post-processing components, and configuration management. Among these components, the data state perception component realizes real-time analysis of the reporting status of various meteorological data in the sky engine, and sends scheduling messages to the task scheduling execution component when the data reporting rate meets scheduling requirements. The task scheduling execution component combines the necessary resource information for the algorithm and computing nodes optimization, generates task scheduling instructions, and implements algorithm startup execution. The post-processing phase of task scheduling includes gathering and updating algorithm execution status, calculation node status, and sending of alarm information for algorithm execution abnormalities. Configuration management supports configuring data-aware scheduling parameters on the front-end page.Real-time analysis of data status and scheduling enables efficient task scheduling that starts and runs the algorithm as soon as data are reported. The scheduling delay is significantly reduced, compared to the original schedule, from 3784 ms to 11 ms. Data-arrival scheduling, as the core capability of CMA Big Data and Cloud Platform, is deployed and operated in real-time in provinces and regions. Currently, the system supports the efficient scheduling of 19 core business algorithms at the national level, with a total of approximately 6.67×105 daily scheduling tasks and an average scheduling delay of 31 ms. Efficient scheduling is achieved with 14 algorithms supported at the provincial level, encompassing a total of approximately 8×104 daily scheduling times and an average scheduling delay of 156 ms. In addition, data aware scheduling achieves seamless integration of upstream and downstream algorithms in meteorological services, providing a solution to eliminate the problem of disconnection between meteorological services and improve collaboration between meteorological services.

High-velocity air-fuel spray （HVAF） technology was used to prepare two kinds of Al-based amorphous alloy coatings with high porosity （HP） of 1.36% and low porosity （LP） of 0.86%. The effects of porosities on the corrosion behavior of Al-based amorphous alloy coatings were studied. The porosities and microstructures of the coatings were analyzed by scanning electron microscope （SEM） and X-ray diffraction （XRD） combined with three-dimensional X-ray tomography （3D XRT）. The corrosion properties of the coatings were studied by electrochemical testing system and contact angle measuring instrument. The passive film components of the two coatings were analyzed by X-ray photoelectron spectroscopy （XPS）. The results show that the self-corrosion current density （Icorr） and pitting potential （Epit） of the LP coatings are 3.0×10-6 A/cm2 and -0.40 V， respectively. The Icorr and Epit for HP coatings are 6.0×10－6 A/cm2 and -0.47 V， respectively， signifying that the LP coating has better resistance to the localized corrosion； the charge transfer resistance （Rct） of LP coatings is about twice than that of HP coating； the LP coating has a larger contact angle， which proves that LP coating has better hydrophobicity and stronger corrosion resistance； the contents of RE2O3 in the passive film formed on the LP coating are larger， which further indicates that LP coating has better corrosion resistance.

Currently, there is a high latency problem in the transmission of video surveillance data in coal mines, and the main cause of video transmission delay is encoding delay. In order to solve the above problems, a intelligent monitoring video transmission method for coal mines based on media supplemental enhancement information(SEI) without video encoding is proposed. This method caches a copy of the compressed video frame obtained by demultiplexing the video stream, and decodes the compressed video frame to obtain the decoded video frame. The method stores the AI model analysis results in the decoded video frame through SEI, writes the custom SEI into the network extraction layer unit corresponding to the compressed video frame copy of the decoded video frame based on the timestamp correspondence. The method multiplexes the compressed video frame copy to achieve real-time transmission of coal mine intelligent monitoring videos. Experimental testing of this method is conducted on a 24 core CPU. The results show that for videos with a resolution of 1280×720, the overall CPU utilization rate for video processing using this method decreases from 24.7% to 36.3% when using traditional methods to 20.3% to 23.9%. The end-to-end delay decreases from 1946 ms to 345 ms. For videos with a resolution of 1920×1080, the overall CPU utilization rate for video processing using this method decreases from 29.2% to 41.8% using traditional methods to 18.5% to 26.3%. The end-to-end latency decreases from 6204 ms to 479 ms. This method reduces the transmission delay of coal mine intelligent monitoring videos by avoiding the video encoding process, saves CPU or GPU resources required for video encoding, and reduces the hardware cost of the intelligent video monitoring system.

Purposes As a coal based solid waste rich in silicon and aluminum oxides, utilization of coal gangue is crucial for the sustainable development of coal industry. Methods Integrated grinding modification of calcined coal gangue and aluminate coupling agent to prepare rubber reinforcement was proposed. The influences of grinding time and the amount of modifier on the surface modification were investigated. Ultrafine particles were obtained through air flow classification, and the influences of modification or not and particle size on the reinforcing and filling properties of rubber were analyzed. Findings The results show that the best comprehensive modification effect is achieved when the duration of ball milling is 30 min and the amount of aluminate coupling agent is 2%. The characteristic functional groups of aluminate coupling agent appear on the surface of coal gangue. Compared with the rubber filled with commercial silica, the rubber filled with the air-flow graded modified filler possesses higher hardness and crosslinking density, its vulcanization performance is better, the tensile strength, elongation at break and permanent deformation at break are reduced, and the fixed extension stress is increased. The particle size distribution of the filler has an obvious effect on the properties of rubber, with the decreases of the particle size of the filler, the vulcanization property is improved, and the tensile property is also improved. The reinforcement performance of modified superfine coal gangue as filler is close to that of silica, which has the potential to replace silica.

As a new type of bevel gear, the equal-distance spiral bevel gear is suitable for the mass production by metal powder injection molding (MIM) due to the characteristic as the normal equal-distance of spiral tooth surface. According to the coordinate transformation theory, the parametric equations of spherical involute and equal-distance conical spiral curves were derived. The mathematical model of tooth surface was established by the formation principle of tooth surface. The mathematical model of tooth surface was programmed by MATLAB to calculate the coordinates of discrete points on tooth surface, and the accurate modeling of equal-distance spiral bevel gear was completed by reverse engineering of UG. The meshing contact of equal-distance spiral bevel gear was simulated to obtain the transmission performance in ANSYS. Finally, the trial production of equal-distance spiral bevel gear was completed base on the MIM process. In the results, the mathematical model of tooth surface combined with the inverse modeling of discrete points can ensure the accuracy of 3D model, and MIM process can be used to produce the equal-distance spiral bevel gears for mass production.

Hydrogen energy storage has many characteristics such as large energy storage capacity, long storage time, clean and pollution-free, and it realizes the interconnection and complementation of multiple energy networks and collaborative optimization. It is expected to become an important supporting technology to promote the development of distributed energy and improve the efficiency of terminal energy utilization. In order to improve the reliability and renewable energy utilization rate of islanded microgrid, the operation characteristics of typical electric, hydrogen and thermal devices are analyzed, and a multi-objective optimization configuration model of the islanded microgrid is proposed. Then, the target problem is solved based on simulated annealing particle swarm optimization (SAPSO) algorithm to obtain technical and economic indicators under different configuration schemes. Finally, based on the annual natural resource and electric heating load characteristic curve of a certain place in the north, the model built on MATLAB can effectively promote that the load loss rate of the proposed multi-energy complementary configuration scheme decreases by 3.18%, and the utilization rate of renewable energy increases by 8.37% compared with the traditional electric energy storage configuration scheme. Thus, the proposed configuration scheme can effectively promote the consumption of renewable energy and ensure the economy and power supply reliability of the independent micro-grid.

Background: The most effective method for improving the prognosis of lung cancer is the application of low-dose computed tomography (LDCT) for pulmonary nodule screening in populations at high risk. Timely diagnosis and treatment of early-stage lung cancer can contribute to higher long-term survival rates. However, it remains difficult to differentiate malignant from benign pulmonary nodules measuring 8–15 mm, and avoid overtreatment on the one hand and delayed diagnosis on the other hand. In this consensus paper, we aimed to clarify the definition of “high-risk indeterminate pulmonary nodules (IPNs)” and discuss appropriate evaluation and management to facilitate timely diagnosis of lung cancer to improve lung cancer outcome. Direction for future research was discussed. Methods: A multi-disciplinary panel of doctors and IT experts from Asia, Canada and the U.S. were invited to participate. Published evidence and consensus guidelines were used to develop this consensus was clarified. Their evaluation and management were discussed. Findings: The experts believed that the prevalence of pulmonary nodules was very high, and it that was difficult to diagnose early-stage lung cancer due to the small size of the nodules, often leading to delayed diagnosis or overtreatment. To address this issue and to improve long-term outcome, the panel considered important to revise the classification of high-risk IPNs, (1) as pulmonary nodules that cannot be clearly diagnosed with non-surgical biopsy procedures, but is highly suspicious for early-stage lung cancer. The panel also recommends the most responsible should arrange imaging evaluations and follow-ups, taking new technologies into account. Artificial intelligence (AI) assessment based on the Medical Internet of Things (MIoT) can be combined with expert opinion to form a human–computer multidisciplinary team (MDT) that can fully implement the three core procedures of the MIoT, namely, comprehensive perception, reliable transmission, and intelligent processing. This will help to upgrade the non-standard diagnosis and treatment, the so-called “handicraft workshop model”, to a modern assembly-line model that meets international standards. The MIoT technology, which has the potential to realize “simplification of complex problems, digitalization of simple problems, programming of digital problems, and systematization of programming problems”, can promote the homogeneous evaluation of pulmonary nodules by enhancing both the sensitivity and the specificity of detecting early-stage lung cancer, in order to avoid delayed diagnosis and overtreatment. Conclusion: To optimize the evaluation of early-stage lung cancer, and to avoid delayed diagnosis and overtreatment, it is necessary to propose and promote the concept of “high-risk IPNs”. The application of current technologies, AI, and a human–computer MDT, will facilitate improvement in nodule evaluation, transforming the current diagnosis and treatment model, which is akin to production in handicraft workshops, into a modern assembly-line model that meets international standards, and will ultimately result in better prognosis.

With the trend of global climate change, it is important to study the high temperature heat damage of tea plants and analyze the spatial and temporal distribution characteristics to warn damage early and reduce production losses. An index is established based on daily maximum air temperature and historical heat damage disaster records at 510 meteorological stations over tea regions in Southern Yangtze River and South China from 1961 to 2022, to determine and verify the extent of high temperature heat damage, using methods of disaster inversion and K-means clustering analysis method. The spatial and temporal distribution characteristics of high temperature heat damage are analyzed. The total days with moving average of 14-consecutive-day maximum temperature above 34.5 ℃ are statistically analyzed, and for mild, moderate and severe high temperature heat damage, the value is in the range of 1-17 d, 18-38 d and above 38 d, respectively. The accuracy rate of complete compliance with the validation sample is 73.9%, and the accuracy rate of basic compliance is 91.3%. The total number of heat damage on tea plants in Southern Yangtze River and South China shows fluctuating changes from 1961 to 2022. The total number of heat damage on tea plants in tea regions of Southern Yangtze River and South China is the lowest in 1999 and 1997, respectively, while numbers are the highest in 2021 for both tea regions. Compared to tea regions of Southern Yangtze River, there are more high temperature heat damages in South China, especially mild high temperature heat damages. Moreover, the number of high temperature heat damage on tea plants in South China shows a significant increasing trend in the past 62 years, but the trend of changes in the number of high temperature heat damage on tea plants in most tea regions of Southern Yangtze River is not significant.

Today’s society promotes and improves teaching in various ways. However the teaching of spoken English still lacks the guidance of scientific method. The importance of oral teaching is becoming more and more prominent in English teaching. Therefore, this paper proposes specific oral teaching training strategies to explore effective methods of oral evaluation after applying the DTW construction strategy. The cultivation strategy of spoken English has been improved from the perspective of teachers. The speech evaluation system is designed and implemented to normalize the speech signal and then add windows to it in frames. SMFCC, volume intensity, and fundamental trajectory were chosen as the feature parameters of the system comparison. Parameters were extracted from the amplitude spectrum, and after feature extraction, parameter distance calculation was carried out on the feature parameters so as to get the results of English-speaking level scoring. According to the study, the teaching model that incorporates the English-speaking development strategy significantly improves the students’ speaking ability compared to the control class. Moreover, the evaluation system’s performance in terms of exact agreement rate and neighbor agreement rate is consistently above 90%, which indicates that the system can objectively evaluate the students’ oral proficiency.

In order to improve the defect recognition efficiency of transmission lines, the industry is currently using aerial images for automatic visual defect detection to ensure the safe operation of transmission lines. This paper proposes a method for defect recognition from coarse to fine, based on convolutional neural networks and connected domain algorithms, to improve recognition accuracy. The recognition speed is improved by using the knowledge distillation method of target detection networks based on decoupled features, adversarial features, and attention features. It has been found that the optimized recognition model improves the precision rate by 7%, the recall rate by 8%, and the average accuracy rate by 10%. The FPS of the model optimized by knowledge distillation is 62.5, and the average value of the FPS of other versions of this model is 47.35. It is believed that the two optimization ideas introduced in this paper can enhance the previous transmission line defect recognition algorithm in terms of accuracy and recognition speed.

With the increasing demand for high-quality skilled talents, building a teaching management system suitable for the characteristics of modern apprenticeship is the key to ensuring the smooth implementation of practical teaching. After the contemporary apprenticeship quality management system, this article takes vocational college students under the current apprenticeship management system in S city as the research object, uses principal component analysis and multiple choice linear regression methods to evaluate student initiative and explore the relevant influencing factors, Assess the impact and degree of influence of various factors on the agency of vocational college students. The results show that motivation investment (0.2421) and emotional investment (0.2335) are closely related to the evaluation results of student agency. The agency of the selected students is at a lower than average level, with an evaluation score of 2.9096. The impact value of the modern apprenticeship management system on student agency is 3.561, above average. Among them, The impact of factor process (3.838) is the greatest

Computer teaching in colleges and universities under the background of informationization is developing rapidly, but the teaching mode still has more serious problems, and computer teaching reform needs to be emphasized. This paper first proposes solutions to the problems of computer teaching in colleges and universities. Secondly, it uses hierarchical analysis to construct a computer teaching evaluation system model, then carries out educational information data mining through the DMOTE method, and uses C4.5 to optimize the model of DMOTE. Setting up a controlled experiment to analyze the students’ performance after receiving teaching reform, most of the students in the experimental group scored in the two segments of 80-89 and 90 or more, accounting for 60%, and the number of students scoring less than 60 points was less, only 6%. After the reform of the computer model, the students’ performance improvement is more obvious, and the reform effect is good.

The global system of nature reserves is facing adjustment and restructuring towards the goal of harmonizing ecological conservation with regional development. We use multiple ecoregion data at both global and national scales as ecological indicators to explore the gap areas of China's nature reserves, which can help to build a global network of nature reserve systems and lay a spatial foundation for global biodiversity conservation. This paper comprehensively resorts to the ideas and modeling approaches involved in gap analysis, conservation prioritization analysis and eco-region planning. After identifying in both global and national scales the potential areas with gaps in national nature reserves in China, it proposes conservation priority areas and optimization strategies. The study finds that in a global extent, the areas with the gaps in China cover a large area and are distributed widely, mostly on the both sides of the Tengchong-Heihe Line. The conservation priority areas are concentrated in mid-subtropical humid areas, plateau subtropical sub-humid areas and semi-arid areas, and plateau temperate humid/sub-humid areas. These areas are usually not sufficiently protected due to their diversified landforms, complex ecosystems and lack of protection measures. The results have verified and identified the areas with gaps in the building of Chinese national nature reserve system. They may make a unique and important contribution to global ecological conservation efforts in terms of protected area system optimization and conservation network building. Synopsis: This paper analyses the conservation gaps in China's national nature reserves and proposes conservation priority areas for optimising the layout of the nature reserve network.

In this work, the microstructure and properties of Nb-16Si-24Zr alloy directionally solidified by electromagnetic cold crucible under different process parameters were investigated. As the pulling rate increases, the size of both primary Nbss and eutectic Nbss decreases, resulting in a straighter primary dendrite γ-Nb5Si3 and a fishbone like Nbss/γ-Nb5Si3 coupling structure of secondary eutectic. As the power supply increases, the size of the nascent Nbss and γ-Nb5Si3 increases, and the coupling growth trend of Nbss and Nb5Si3 weakens. As the pulling rate and power supply increase, the toughness shows a trend of first increasing and then decreasing, while the room temperature compressive strength gradually increases.

Maritime activities play a crucial role in the social and economic development of human societies. Many countries around the world have become powerful as a result of the flourishing maritime activities. However, maritime activities entail high risks, making ship navigation safety a paramount concern for maritime authorities, practitioners, and scholars worldwide. In recent years, the continuous growth in the number and tonnage of vessels, coupled with the increasing density of waterway traffic, has posed a serious threat to maritime safety, leading to a rise in maritime accidents. This paper conducts a comprehensive analysis by examining distress alarm data from the Guangzhou Coastal Radio Station over a decade from 2010 to 2019, and integrating it with Port State Control (PSC) inspection data from the Guangzhou Port Supervision and Inspection Station. The aim is to explore scientific and effective approaches for analyzing the safety status of ship navigation, preemptively preventing maritime accidents, and thereby providing valuable insights for maritime management agencies and navigation security departments to enhance their maritime management capabilities and navigation safety service levels.

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The Nb-16Si-20Ti-4Cr-1.5Al-4Hf-4Zr-1Ta-xB (x=0, 2, 4)-yMg (y=0, 0.2, 0.4) alloys were prepared by non-consumable arc melting. The effects of B and Mg addition on the microstructure and room temperature fracture toughness have been investigated. The results reveal that when the content of B element reached 4 at.%, the intermediate metastable phase Nb3Si was precipitated in Nb-Si based alloys. The cooperation of B and Mg synergistically enhances the room temperature fracture toughness of Nb-Si based alloy. B and Mg element causes the eutectic point of Nb-Si based alloy to shift to the right. The 2B-0.4Mg alloy shows the best fracture toughness, and its KQ value is 14.41 MPa·m 1/2, which increased by 34% compared to the matrix alloy. Crack deflection and secondary cracking increase the room-temperature fracture toughness of Nb-Si-based alloys.