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[Objective] This study aims to investigate the mitigation effect and physiological mechanism of salicylic acid (SA) on high temperature stress injury of watermelon seedlings, and to provide a theoretical basis for the application of SA in watermelon cultivation. [Methods] Potted ‘K53’ watermelon seedlings in greenhouse were used as experimental materials. After spraying different concentrations (0, 0.5, 1.0, 1.5, and 2.0 mmol/L) of SA on the leaves, the seedlings were stressed at 42 ℃ for 36 h. The growth characteristics, anatomical structure, physiological and biochemical indexes of watermelon seedlings were observed, and the mitigation effects of each treatment were comprehensively evaluated by membership function method. [Results] After high temperature stress, the leaves of watermelon seedlings were wilted seriously, the growth of root length was inhibited, the leaves became thinner, and the mesophyll cell structure was damaged. After SA application, the leaves became thicker, photosynthetic pigment content, photosynthetic gas exchange parameters, antioxidant enzyme (POD, SOD, CAT) activity and osmotic adjustment substances (proline, soluble sugar, soluble protein) content were increased significantly, while MDA content and relative conductivity were decreased significantly. Compared with the high temperature stress group, the MDA content and relative conductivity of leaves under 1.0 mmol/L SA treatment were reduced by 33.70% and 58.58%, while the contents of chlorophyll a and chlorophyll b, net photosynthetic rate, and the activities of SOD and CAT were increased by 22.71%, 21.63%, 98.34%, 23.98% and 19.71%, respectively. [Conclusion] Pre-spraying SA could alleviate the damage of watermelon seedlings under high temperature stress, with 1.0 mmol/L SA had the best effect.

Objective To explore the effect of personality characteristics on the facial esthetic satisfaction of edentulous patients, in order to provide reference for improving esthetic satisfaction after complete denture restoration. Methods Twenty-two edentulous subjects were randomly selected. Before complete denture treatment, the emotional stability of patients was assessed by Eysenck personality questionnaire N scale score(EPQ-N). Before and three months after treatment, patients completed the orofacial esthetic questionnaire, and 3D stereophotogrammetry was performed to evaluate the changes in facial appearance. In addition, multiple linear regression model was established by using N scale score, changes in facial appearance and facial esthetic satisfaction score. Results After complete denture treatment, the difference in the ratio of the middle and lower parts of the face between patients and the normal group was reduced by (3.85±2.63)%, and the difference of the nasolabial angle between patients and the normal group was reduced by (6.66°±5.39°). The multiple linear regression model showed that N scale score and changes of the differencein the facial proportion between edentulous subjects and normal population were influencing factors of patients’ esthetic satisfaction on the facial appearance, and the N scale score and changes of the difference inthe nasolabial anglebetween patients and normal population were influencing factors of the patients’ aesthetic satisfaction on the facial profile. Moreover, the effect of two independent variables(N scale score and facial soft tissue change)on the aesthetic satisfaction of facial appearance and facial profile was statistically significant(P

Multi-source observations are used to comprehensively analyze the Doppler weather radar characteristics of strong storms and the formation mechanisms of surface damaging wind induced by two strong downbursts, occurred in Shandong on 2 June 2017 and 6 August 2017. It's found that two damaging wind events occurs under strong synoptic scale weather system forcing and favorable meso-scale environmental conditions, the relatively isolated supercell storm on 2 June (6·2 supercell) and strong single storm on 6 August (8·6 strong single storm) fiercely develop into series of downbursts, which leads to the occurrence of large-scale damaging winds. As two strong downbursts induced by 6·2 supercell storm and 8·6 strong single storm evolves, the vertically integrated liquid water content radar parameter first rises and then quickly plunges down. During 6·2 supercell storm, a powerful downburst descends sharply, causing the mesocyclone's top and bottom to shoal and its thickness to decrease. The occurrence of two strong downbursts are accompanied by obvious radar characteristics including reflective factor core rapid decline, high value area of radial velocity at low elevation, strong divergence at bottom, remarkable mid altitude radial convergence and severe divergence at upper-level. 6·2 supercell storm is characterized by intense rotation. Its mesocyclone lasts for a long time and extends deeply both upwards and downwards. Additionally, there are arc-shaped inflow notches and hook echoes at low levels of 6·2 supercell storm. 8·6 strong single storm is characterized by significant low-level convergence. Besides, there is a convergence zone at or near the surface formed by the outflow of the strong downburst and the inflow in front of 8·6 strong single storm. Among all the formation mechanisms of two damaging winds induced by two strong downbursts, the negative buoyancy effect of two storms is basically equivalent, but the cold pool outflow effect is more evident for 6·2 supercell storm, and the downward transport momentum effect is more significant for 8·6 strong single storm. The Nansun Station of Weifang locating right ahead of 8·6 strong single storm's approaching direction, therefore the front divergence flow from the strong downbursts is preferable superimposed on the fast moving homodromous storm, indicating the speed of the front divergence flow better superimposes on the speed of the storm itself, which is crucial for the occurrence of 37.0 m·s-1 extreme wind.

[Objective] This study aims to investigate the carbon storage, carbon sink function, and response mechanism to climate in Pinus sylvestris var. mongolica plantations with different initial planting densities on the southern edge of Horqin Sandy Land. The goal is to facilitate the assessment of the carbon sequestration function and adaptive management of forest ecosystems. [Methods] Estimating carbon storage and carbon sequestration rate of Pinus sylvestris plantations using stand height and cross-sectional area, and analyzing their responses to temperature, precipitation, and evaporation in conjunction with meteorological factors. The GM (1,1) grey prediction model was used to predict forest carbon storage in 2030. [Results] The carbon storage and sequestration rate of Pinus sylvestris plantations with different initial planting densities exhibited similar annual fluctuations, with an overall increase in carbon storage each year. The curve of the sequestration rate showed a “U” shape. Both thinly and excessive initial planting densities can reduce the carbon carbon sequestration capacity of Pinus sylvestris plantations. Before reaching 32 years old, the highest carbon sequestration intensity was observed in stands with initial planting densities of 1 500~2 000 tree/hm2, and for stands aged 35~46 years, the optimal density was 1 000~1 200 tree/hm2. The carbon storage increased logarithmically with increasing stand density.The response pattern of the planted Pinus sylvestris forests’carbon sequestration rate differed among stands with different initial planting densities regarding temperature but not precipitation. For high and extremely high-density Pinus sylvestris plantations, the average temperature in August of the previous year and in March, May, June and July of the current year were the main climatic factors limiting carbon sink. For low and medium-density plantations, the average temperature in August of the previous year and in March and October of the current year were the main climatic factors that constrain carbon sink. The correlation analysis between evapotranspiration and carbon sequestration rate in different planting density stands showed that carbon sink of low-density Pinus sylvestris plantations was more sensitive to evapotranspiration. Based on the GM (1,1) grey model, it was found that excessively high or low initial planting density would reduce the carbon sequestration potential of future Pinus sylvestris plantations. The optimal planting density for carbon sequestration rate was 1 772 tree/hm2. [Conclusion] The initial planting density of Pinus sylvestris has a significant impact on carbon storage and carbon sequestration, as well as their response to climate change in sandy areas. Adjusting the initial planting density may be one of the key adaptive management measures for Pinus sylvestris plantations under climate change.

The situation of coal as the stabilizer guarantee the energy safety in China cannot be changed in the short term, and it will continue to face the problems of coal resource protection and the low utilization rate of coal-based solid waste. Through innovative mining methods, improving the recovery rate of coal resources and the large-scale disposal of coal-based solid waste, a new path is being paved for the green and sustainable development of the coal industry. Based on the in-depth research on the development status of coal mining technology, a new roadway excavation method of “excavation-backfill-retention” is proposed. This paper systematically discusses the scientific problems and key technologies of the “excavation-backfill-retention” construction method from three aspects: rapid excavation, continuous and efficient backfilling and safe construction of large-section roadways. The research results show that ① aiming at the engineering problems such as the fast excavation of large section roadway and the stability control of surrounding rock of heading face, three scientific problems are summarized: the matching mechanism between coal and rock characteristics and cutting parameters of roadway boring machine, the spatial transfer mechanism of overburden load and the deformation mechanism of surrounding rock, the interaction relationship between anchor/cable roof and support mechanism. The technology system has been built, which is based on the real-time sensing of the geological environment in the excavation area, the intelligent cooperative operation of the multi-process of falling, loading and transporting coal, the aging control of surrounding rock of the drilling anchor support together with excavation, the anti-leakage and ventilation optimization of the large section roadway. ② The scientific problems of continuous and efficient backfilling are summarized from the two aspects of timely construction of large section roadway bearing system and its bearing performance regulation, including the co-bearing mechanism of background coal anchor/cable, the hydration consolidation mechanism of multi-component solid waste base backfill materials, and the space-time evolution law of physical and mechanical characteristics of backfill are clarified. A continuous and efficient backfill key technology system with the core of safe and efficient backfill space construction, backfill material performance control and backfill material flow-consolidation perception has been established. The breakthrough of relevant theories and technologies can provide a theoretical basis for raw material selection and ratio design of backfill materials, additive development/selection and working performance control, excavation rate and backfill step optimization design, consolidation monitoring of backfill body, etc. ③ Based on the key problems of roadway safety and surrounding rock easy to break, sheet and damage in the whole life cycle, the paper elaborates three scientific problems: the spatial and temporal distribution characteristics of stress field of roadway surrounding rock, the evolution mechanism of roadway deformation and damage, the engineering quality monitoring and stability regulation theory of roadway surrounding rock. The key technology system is formed with the intelligent stability warning of the rock surrounding the roadway and the deformation control of the rock surrounding the roadway as the core. It is of great significance to conduct the scientific research and technical demonstration of the “excavation-backfill-retention” construction method in coal mines, and to realize the synergy of large-scale solid waste disposal, efficient coal pillar section recovery and rapid roadway excavation, which can promote the green and low-carbon transformation and development of the coal industry.

The shield type temporary support robot is an important component of the intelligent excavation robot system for large section roadways that adapts to the coexistence of dirt and debris. Its main function is to provide a safe and reliable workspace for achieving 'parallel excavation and support' operations. In order to enhance the safe and stable support of the shield type temporary support robot for surrounding rock during its pushing and driving process, based on the structure, working environment, and operational requirements of the shield type temporary support robot, a mathematical model of its pushing amount and support force during pressurized driving, as well as a dynamic model of pressurized driving, are established. A hydraulic control system for the shield type temporary support robot driving under pressure is designed. The system mainly consists of a support hydraulic system and a driving hydraulic system. During static support, the support hydraulic system needs to constantly output a support force greater than the weight of the upper shield body itself, and the driving hydraulic system is in standby mode. When driving under pressure, the support hydraulic system and the driving hydraulic system work simultaneously, ensuring that the temporary support robot 'reducing stress without leaving the roof' while steadily moving forward with the roof under pressure at all times. A precise control method for shield type temporary support robot driving under pressure based on fuzzy PID is proposed. The pressure and displacement signals of the temporary support robot are collected in real time by displacement sensors integrated on the displacement cylinder and pressure sensors in the hydraulic circuit. The signals are used to reflect the changes in support force and driving displacement during the temporary support robot's driving under pressure. Based on the error and error rate of the support force and displacement, the fuzzy PID algorithm is used to modify the control parameters of the support force and displacement, achieving reliable control of driving under pressure based on the fuzzy PID algorithm. Both simulation and experimental results show that the effect of fuzzy PID control is superior to traditional PID control. Under fuzzy PID control, the relative error of support force during the pushing and driving process of the shield type temporary support robot is less than 1%, and the driving displacement error is less than 2 mm. Moreover, the response speed of support force and pushing amount control is fast, ensuring the safe and stable support of the surrounding rock during the pushing and driving process.

Membrane separation has been widely used in the field of water treatment due to its characteristics such as operation at room temperature, high separation efficiency and environmental friendliness. However, membrane pollution caused by suspended substances or soluble substances in the feed solution limits the further development of membrane technology. Photocatalytic membrane can use photocatalyst to degrade the pollutants on the membrane efficiently and improve the separation efficiency and anti-pollution performance of the membrane. This paper firstly introduced the types of photocatalysts used for the preparation of photocatalytic membrane, including metal oxides, graphite phase carbon nitride, bismuth-based materials and new two-dimensional materials. Then the construction methods of photocatalytic membranes with self-cleaning ability (surface modification and matrix blending of membrane) were reviewed, and the pollutant removal mechanism of photocatalytic membrane was summarized. The application scenarios of photocatalytic membrane for dyes, antibiotics, emerging pollutants in wastewater treatment of different industries were listed. Finally, the article gave an outlook on its future development and provided a certain reference for the development of highly anti-pollution membrane materials.

To improve the testing efficiency of computer interlocking systems and shorten the testing cycle of urban rail transit projects, this paper proposes an automated testing method for interlocking data of signaling systems for urban rail transit. Built upon testing scripts, this method is devised to describe testing scripts using non-programming languages, allowing for the control of interlocking software without modifying the software itself or integrating additional communication interfaces. This data-driven approach automatically generates testing scripts, utilizing data such as interlocking tables and interface code tables. Following the parsing process of testing scripts, it enables the transmission of control commands to the interlocking system, state collection of tested devices, and determination of testing results. The proposed method has been applied in the construction of the west extension of Line 2 (Phase II) in the Changsha Urban Rail Transit. Through comparing the results from automated and manual testing in this project, the automated testing approach exhibited an overall defect recognition rate of 85%, particularly a defect recognition rate of 100% for interlocking tables, and a decrease in actual time consumption of 76% in comparison with the manual mode, verifying the effectiveness of the method. This method has also contributed to a significant improvement in testing efficiency.

【Objective】The study was conducted to clarify the microbial community structure in soil with continuous cropping of Curcuma wenyujin and fumigation treatment, aiming to lay a foundation for alleviating continuous cropping obstacles in C. wenyujin cultivation.【Method】The soil under a continuous cropping of C. wenyujin for 3 years was selected and fumigated with dazomet one month before planting C. wenyujin. After 7-month cultivation of C. wenyujin, we collected soil samples from three types of plots: continuous cropping, fumigated and uncultivated. Total soil DNA was extracted, and the population and diversity of microbial communities (fungi and bacteria) were analyzed by using PacBio Sequel thirdgeneration sequencing.【Result】The results showed that C. wenyujin plants in the fumigated soil exhibited good growth and minimal disease incidence, while those in the continuous cropping soil had poor growth and severe seedling death. Analysis of bacterial communities at the phylum level revealed that the abundance of AD3, TK10 and WPS-2 decreased in rhizosphere soil after continuous cropping compared with those in uncultivated soil. Fumigation of continuous cropping soil increased the abundance of beneficial bacteria with biocontrol functions such as Bacillus and Sphingomonas. Among the three soil types, 5 fungal phyla were abundant, including Ascomycota, Basidiomycota, Chytridiomycota, Mortierellomycota, and unclassified_k_ Fungi. Ascomycota had the lowest abundance in uncultivated C. wenyujin soil, but continuous cropping significantly increased its abundance, while Basidiomycota showed a significant decrease. Several beneficial fungal genera, including Chaetomium, Penicillium, Aspergillus, Myrothecium, Thielavia, Humicola, Rhizophlyctis, Microdochium, Ramicandelaber, Albifi mbria, Curvularia, Gigaspora, Nigrospora, Neocosmospora, Talaromyces, Roussoella, Rhytidhysteron, Boothiomyces, Apiotrichum, Ochroconis, Saitozyma, Trichosporon and Phoma, had higher abundance in fumigated soil than that in continuous cropping soil. In contrast, continuous cropping soil had a higher accumulation of pathogenic microorganisms.【Conclusion】Continuous cropping of C. wenyujin leads to the accumulation of harmful soil microorganism, resulting in continuous cropping obstacles. Fumigation with dazomet can reduce the number of soil-borne pathogens and increase the abundance of beneficial microbial populations, thereby mitigating continuous cropping obstacles in C. wenyujin cultivation.

Objective Over-excavation in tunnel construction, mainly caused by inappropriate blasting,will affect the smooth progress and safety of tunnel excavation, increase construction cost and reduce economic benefits. In order to radically solve this problem, blasting design and blasting construction technology should be studied and optimized. Method Based on the shallow buried unsymmetrical pressured layered railway tunnel project for Chongqing Railway Hub East Ring Line(Chongqing East Ring Railway),the causes of vault, arch haunch and arch foot over-excavation are analyzed with theoretical method and modern computer technology. The drilling positions are designed with dynamic optimization, and control measures and solutions for over-excavation are put forward. Result & Conclusion Over-excavation at the tunnel vault is mainly caused by the secondary disturbance of the surrounding rock in smashed area by mechanical excavation after blasting, and over-excavation at the arch waist and arch foot is mainly caused by the improper amount of blasting explosive and improper drilling. In addition, the existence of rock cracks will also lead to significant decrease of the surrounding rock strength. Therefore, proper blasting and under-excavation should be done at the vault to reduce the disturbance of the surrounding rock, and then manual + mechanical excavation and trimming should be combined to reduce the amount of over-excavation. Secondly, according to the attributes of surrounding rock, and based on GA-SVR model and genetic algorithm, the blasthole spacing is properly optimized. On-site monitoring results show that in the initial stage without optimized blasthole spacing, the over-excavation in cracked stratum is about 40cm, which is reduced to about 9cm after the blasthole spacing optimization. The results indicate that optimizing the blasthole spacing can effectively control tunnel over-excavation. The above results can provide reference for similar projects.

Hormonal receptor positive human epidermal receptor 2 negative (HR+/HER2-) is the commonest molecular subtype of breast cancer (BC). Patients with HR+/HER2- BC may manifest clinically a late recurrence whose BC metastasizes 10-15 years post-operatively. We report one case who presented with pulmonary mass in upper lobe of lung and Horner syndrome 16 years after BC surgery. FDG PET/CT suggested pulmonary malignancy but could not differentiate between primary or metastatic cancer when invasive biopsy was quite risky. Novel 18F-FES PET/CT facilitated the non-invasive functional diagnosis of estrogen-receptor positive (ER+) pulmonary metastasis of BC, and the patient experienced partial response (PR) after CDK4/6 inhibitor and aromatase inhibitor as endocrine therapy. This article reviews the diagnosis and treatment process of this case, to provide guidance for non-invasive global evaluation of ER status among metastatic HR+/HER2- BC patients with 18F-FES PET/CT.

Regeneration of adsorption saturated activated carbon by traditional electrochemical technology has the advantages of high regeneration efficiency and no mass loss of activated carbon, but it has defects such as low mineralization efficiency, generation of toxic by-products, and high energy consumption. Electrochemical advanced oxidation(E-AOP) regeneration technology can effectively overcome the problems of traditional electrochemical regeneration. In this paper, the regeneration efficiency and mechanism of activated carbon by traditional electrochemical are briefly described, and the effects of operating parameters (current, electrolyte type and concentration, regeneration location,anode material, etc.) on the desorption-adsorption balance and the mineralization efficiency of pollutants are analyzed. The mechanism and application of three types of E-AOP regeneration technologies(electro-Fenton regeneration, electro-peroxone regeneration, and electro-persulfate regeneration) in the process of activated carbon regeneration are summarized. The electric-Fenton regeneration technology has better regeneration effect, and the problem of metal ion pollution in the system can be effectively overcome by new regeneration. The electro-peroxone regeneration technology does not require the addition of any chemicals and catalysts, which is conducive to the control of reaction conditions and automation of the regeneration process. The electro-persulfate regeneration technology is convenient in operation with low energy consumption and wide applicability. Finally, the problems and development prospects of E-AOP regeneration technology are proposed. This review provides theoretical basis for the development of new efficient and environmentally friendly activated carbon regeneration technologies.

Objective The embedded granularity of target minerals refers to their particle size and distribution in ore, which directly influences the design and effectiveness of ore beneficiation processes. Therefore, the measurement of embedded granularity of target minerals is a crucial task in process mineralogy research. In traditional process mineralogy research, the main method for observing and analysing ore samples is to use a polarized light microscopy. However, this approach generally suffers from problems such as long processing times, susceptible to subjective factors, and difficulties in achieving automation and large-scale applications. To overcome these limitations, this paper proposes a method for detecting the embedded granularity of metal minerals under the microscope based on based on deep learning. Methods This method takes specimens from the Shuichang magnetic ore deposit in Tangshan City, Hebei Province as the object. We take photographs under the reflected light conditions using a polarized light microscope to create a dataset, and design a mineral recognition network model based on the Deeplabv3+ network. Thereby it enables automated feature extraction and intelligent recognition of the target metal minerals. This method achieves segmentation of the target minerals by generating binary images of the desired metal minerals. Finally, the analysis and measurement of the embedded granularity of the target metal minerals are completed by combining the maximum Feret diameter. Results Compared with traditional manual microscopic measurement methods, the application of image measurement based on deep learning in mineral particle analysis has increased the processing speed by approximately 119.8 times and the measurement accuracy 169.5 times when measuring the same mineral particles, demonstrating its significant improvement in terms of processing efficiency and measurement accuracy. Conclusion The deep learning-based method for detecting the embedded granularity of metal minerals under a microscope significantly reduces the detection time and enhances the detection accuracy for mineral embedded granularity. Moreover, it eliminates the influence of subjective factors, which is of great significance for promoting the intelligent development of process mineralogy.

Objective To investigate the effects of a 45% high-fat diet (HFD) with isocaloric intake on energy metabolism and endurance exercise capacity in SD rats. Methods Twenty-four male SD rats were randomly divided into normal chow diet group (CON), HFD group, normal chow diet+exercise training group (CONT), and HFD+exercise training group (HFDT). The CON and CONT groups received normal chow diet, while the HFD and HFDT groups received a 45% high-fat diet with isocaloric intake. The HFDT and CONT groups underwent an endurance training of moderate-intensity running for 6 weeks. Body weight, fat mass, and lean mass were measured weekly. Energy expenditure and basal metabolic rate during rest and exercise states were measured using Pheno Master/Calo Treadmill system. Blood glucose, lipids, and creatine kinase levels were detected after the exhaustion test. Results In 6 weeks after intervention, the endurance exercise capacity was significantly enhanced in the HFDT group than the CONT group (P < 0.05). There were no obvious differences in body weight and body composition among the groups under isoenergetic feeding conditions. At rest, no statistical differences were observed in total energy expenditure and basal metabolic rate among the groups. However, prior to the 4th week, the CON group primarily metabolized carbohydrates while the HFD group primarily metabolized fats. But the carbohydrate metabolism was decreased and then increased, and the substrate metabolism rates eventually reached similar levels between the 2 groups on the 5th to 6th week. The HFDT group primarily metabolized fats while the CONT group primarily metabolized carbohydrates, with significant differences persisting after 6 weeks of training (P < 0.05). HFD led to elevated levels of serum cholesterol, triglycerides (TG), and high-density lipoprotein cholesterol (HDL-C), but, endurance training resulted in decreased lipid levels in the HFDT group, accompanied by an increase in β-hydroxybutyrate (βHB) level (P < 0.05). Isoenergetic diets had no significant differences in their effects on liver and kidney function or muscle damage indicators. Conclusion An isoenergetic HFD can improve fat utilization ability and extend endurance exercise time in rats without altering body composition or affecting liver and kidney function.

Objective To explore the clinical efficacy and imaging changes of minimally invasive nonsurgical periodontal therapy (MINST) assisted by endoscopy for deep intrabony defects and to compare its effectiveness with that of traditional scaling and root planning (SRP) to therefore provide a reference for clinical periodontal treatment. Methods Patients with deep intrabony defects ≥ 4 mm in size were selected and divided into two groups: the MINST (MINST, 20 cases, 81 sites) group and the classic scaling and root planing (SRP, 20 cases, 80 sites) group. Before treatment and 12 and 24 months after treatment, probing depth (PD) and clinical attachment loss (CAL) were examined. Moreover, changes in the depth and angle of the intrabony defects were analyzed. Follow-up examination and maintenance treatment should be conducted every 3 months for 12 months after the initial treatment and every 6 months thereafter until 24 months. Results The PD and CAL of patients in both groups continued to decrease (PPPPPPP

In response to the current problems of high startup wind speed, complex design schemes, and inability to accurately measure the average wind speed of the entire section of the roadway using wind speed sensors, based on the principle of ultrasonic opposed wind measurement, a mine opposed wind speed and direction sensor with STM32 as the core is designed. The overall structure of the sensor, the design of the transmitting and receiving circuit, the filtering algorithm, and the software process are introduced. This sensor has changed the wind measurement method from point to surface, using a single ARM core and measuring the wind speed at the centerline of the roadway through long-distance (5-12 m) ultrasonic wind measurement technology. This wind speed represents the average wind speed of the entire roadway. It greatly improves the accuracy and real-time performance of roadway wind speed measurement. A test prototype is developed based on the design scheme, and the test results in a circular wind tunnel show that the measured values of the sensor has good consistency with the standard wind speed values in the range of 0.1-15 m/s, with a measurement error of less than 0.1 m/s. It can meet the precision requirements of intelligent mines for roadway wind speed measurement.

There is a great amount of coal pressed under buildings in our country, while the discharge of coal-based industrial solid wastes such as coal gangue and fly ash are increasing, which has severely restricted the local economic and social development. Taking Mahuangliang Coal Mine in Yulin as the test mine, aiming at the problems of extra-thick coal seam, coal pressed under buildings and high backfilling cost, the technology of full solid waste continuous mining and filling in extra-thick coal seam is put forward. The four-stage process is adopted and the extra thick coal seam is divided into upper and lower parts for secondary mining to control the ground settlement to the maximum extent. In order to reduce the cost of filling raw materials, the source modification of magnesium slag is carried out with chemical optimizer to restrain the cooling pulverization of magnesium slag and stabilize hydration activity. In collaboration with coal based solid wastes such as fly ash and desulfurized gypsum, modified magnesium-cinder based cementing material is developed. The whole solid waste filling material was prepared by cementing coal gangue and fly ash with modified magnesium cinder based cementing material. According to the requirements of strong and weak filling strength in four stages of Mahuangliang Coal mine, different ratios of modified magnesium slag-based filling materials were designed to optimize the ratio and applied to underground filling. The paste filling system and roof-contact method are introduced. The experimental results show that the average uniaxial compressive strength of the 28-day underground filling body exceeds the designed strength by 27%. The leaching toxicity of the core meets the relevant national standards, which successfully liberates the coal resources under the building and has significant social and economic benefits. The practice of full-solid waste cementation and backfilling in the extra-thick seam of Mahuangliang Coal Mine provides a useful reference for similar mines in China, and provides a new idea for the large-scale resource utilization of “coal-electricity-chemical-metallurgical” solid waste in large coal bases in China.

Hybrid F1 is a novel hybrid of Erythroculter ilishaeformis (♀) and Ancherythroculter nigrocauda (♂). Current studies have focused on the genetic features, evaluation of fillet quality, farming techniques, and so on. Meanwhile, few studies have addressed enhancing fillet quality. Traditional intensive pond aquaculture is the major culture method in China. A large amount of excreta and feed residuals remaining in the aquaculture water bodies restricts the critical nutrients, flesh texture, and taste of the fillet. In this study, juvenile hybrid F1 cultured in ponds was obtained from the seed farm (Wuhan Xianfeng Aquaculture Technology Company Limited, Wuhan, Hubei) as the study subject. The fish was treated with short-term micro-flow water (1.2 BL/s) to improve muscle quality. The effects of treatment time (0, 4, 8, and 12 d) on muscle quality in juvenile hybrid F1 flesh were investigated following short-term micro-flow water treatment by assessing the color, muscle fiber, texture, nutrient composition, and the contents of amino acid and fatty acid. The color of the samples was determined by a CR-400 automatic chromaticity meter (Konica Minolta, Japan), wherein the color was expressed by L, a*, and b*. The skin yellowness values were significantly higher at treated 8 d and 12 d, while the short-term micro-flow water treatment significantly influenced muscle redness (P < 0.05). The texture property of fish is one of the keys to its quality. The juvenile hybrid F1 flesh showed a significant improvement in fiber density, hardness, chewiness, and springiness by 70.96%, 92.04%, 198.99%, and 35.71% compared with the control group, respectively after 8 d treatment. Frozen fresh samples were lyophilized for the following analysis. Kjeldahl and Soxhlet-Henkel methods were used for the determination of total, crude protein (N=6.25) and fat content respectively. The protein and fat content significantly decreased in the flesh following the extension of micro-flow water treatment time, while the ash content did not significantly change (P > 0.05, the same below). The amino acid content presented the highest values of glutamic acid, followed by proline, and the lowest values in cystine among the 17 amino acids detected in the fillet of juvenile hybrid F1. The amino acid composition was assayed by a Hitachi L-8900 automatic amino acid analyzer. The amino acids EAA/TAA of all groups were about 40%, and the amino acids EAA/NEAA was over 60%, which were high-quality proteins complied with the Food and Agriculture Organization of the United Nations and the World Health Organization (FAO/WHO) standards. Umami flavors are closely related to the composition and ratio of umami amino acid. The content of total amino acids and essential amino acids showed a decreasing trend under the influence of micro-flow water. The total of delicious amino acid treated at 4 d were significantly higher than those of juvenile hybrid F1 treated at 8 d and 12 d. The TAA content and total EAA content did not dramatically change. The essential amino acid index (EAAI) is used to indicate how close the essential amino acid content is to the standard protein. EAAI were 77.33%, 74.91%, 76.56% and 76.75%, respectively. The fatty acid composition was assayed using gas chromatography (Agilent 7890A, USA). Nineteen kinds of fatty acids were detected in the muscle of juvenile hybrid F1, including 5 kinds of saturated fatty acids, 6 kinds of monounsaturated fatty acids, and 8 kinds of polyunsaturated fatty acids, respectively. The micro-flow water significantly affected the fatty acid content in muscle. The content of cis-15-tetracosenoic acid (6.85 mg/100 g), eicosatrienoic acid (41.05 mg/100 g), and arachidonate (53.84 mg/100 g) was significantly higher than that in the other groups after treatment for 8 d. Meanwhile, the content of α-linolenic acid (48.05 mg/100 g), monounsaturated fatty acid (MUFA) (1 336.43 mg/100 g), and n-6 polyunsaturated fatty acids (524.43 mg/100 g) were higher than that in the other groups at 4 d and 12 d. This study indicated that short-term micro-flow water treatment improves the color of skin and meat, and the meat texture at 8 d while ensuring the quality of the flesh. The short-term micro-flow water treatment can help to provide new ideas to improve the quality of aquatic products cultured in ponds.

In order to provide references for the safe use in engineering applications, the corrosion behavior and post-corrosion mechanical properties of HRB400 reinforcement steel, exposed to a 3.5% NaCl solution in two distinct environments-bare and embedded in concrete were investigated through immersion corrosion test. For HRB400 reinforcement steel embedded in concrete, two approaches were employed: the fabrication of reinforced concrete and the simulation of concrete pore fluid. Initially, HRB400 reinforcement steel, both in bare form and embedded in concrete, was immersed in a 3.5% (mass fraction, the same below) NaCl solution. And soaking the HRB400 reinforcement steel in a saturated calcium hydroxide solution (with addition of 3.5% NaCl solution). The weight loss rate and corrosion rate of the HRB400 reinforcement steel under different corrosion times were calculated separately. Subsequently, the mechanical properties of the corroded HRB400 reinforcement steel were assessed using MTS testing machine. Results showed that as the immersion corrosion time prolonged, the average corrosion rate of HRB400 reinforcement steel across the three environments gradually decreased, while the rate of weight loss increased. Additionally, there was a decline in yield strength, tensile strength, and elongation rate. In the 3.5%NaCl solution, the elongation of HBR400 reinforcement steel in bare form and embedded in concrete decreased with the extension of soak time. However, in the saturated calcium hydroxide solutionl (with addition of 3.5%NaCl solution), the elongation showed a trend of mcreasing and decreasing.

Under the background of “dual-carbon” goal and current technological conditions, coal, waste and carbon constitute an impossible triangle in the coal industry which severely constrains its green, low-carbon, and sustainable development. Adhering to the principles of treating waste with waste and returning the waste to where it comes from, with a focus on the three-dimensional perspectives of damage reduction in coal mining, the functional utilization of mining waste, and low-carbon disposal of carbon in mining industry, this paper explores a synergistic development path for coal, waste and carbon. It provides a comprehensive solution to unravel the impossible triangle and promote the overall green, low-carbon development of coal industry. The specific contributions of this work include: ① Clarifying the scientific connotation of damage reduction in coal mining, the spatial combination characteristics of aquifers in the ecologically fragile areas, the movement patterns of overlying strata under the application of coal mining damage reduction techniques, and the surface deformation patterns resulting from overlying strata damage; proposing the original technologies of drilling-backfilling-retention for section pillar extraction, narrow strip mining with backfill, and backfilling behind fully-mechanized longwall face aiming to address the challenges posed by damage reduction mining; ② Interpreting the scientific connotation of functional utilization for mining waste; clarifying the scientific issues related to the modification methods and mechanisms of magnesium-coal-based solid waste material, the mechanisms of synergistic interactions among diverse solid wastes, and the properties control of total solid waste backfilling materials. These efforts have led to the establishment of a key technological system for the functional utilization of solid waste, with a core focus on the modification of solid waste raw materials, the development of solid waste-based cementitious materials, and the preparation of solid waste based backfilling materials; ③ Elucidating the scientific connotation of low-carbon disposal of carbon with a scientific practical framework and implementation pathway; clarifying some scientific issues related to mineralization material preparation, storage space construction, CO2 storage and control mechanisms, the long-term environmental effects of CO2 storage, and reservoir stability in the low-carbon disposal process of carbon. The scientific issues related to mineralization material preparation, seal space key technologies such as fractured space CO2 storage and CO2 sequestration through coal mine carbon solidification are explicitly defined which results in a new model for achieving a low-carbon CO2 storage in coal mine goaf. Based on the green, low-carbon and sustainable development of coal industry, it is of great significance to collaboratively promote the damage reduction in coal mining, the functional utilization of mining waste, and the low-carbon disposal of carbon. This coordinated effort plays a crucial role in advancing the realization of the dual-carbon goal in the coal industry.

Coal mining machine is the core equipment of completely automated working face, and the research and development of intelligent coal mining robot is crucial for achieving the intellectualization of fully mechanized working face. This paper comprehensively analyzes the current research status of sensing detection, position and attitude control, speed control, cutting trajectory planning, and tracking control in the coal mining machine roboticization process, and proposes five key technologies that must be solved in the development of intelligent shearer robots, including sensing and detection, pose control, velocity control, cutting trajectory planning and tracking control. Aiming at the problem of intelligent perception, this paper proposes the construction thought of a coal mining robot intelligent perception system, as well as the architecture of a coal mining robot intelligent per-ception system. The architecture of the intelligent perception system for coal mining robots is outlined, enabling a comprehensive sensing of running state, posture, environment, and so on, thereby ensuring the safe and reliable operation of intelligent coal mining robots. In terms of the position and attitude control problem of intelligent coal mining robots, the intelligent PID position and attitude control thought is proposed, along with an improved genetic algorithm-based PID pose control method, enabling precise pose control for the coal mining robot. As to the problem of velocity control, the thought of cutting load measurement based on the fusion of “force-electricity” heterogeneous data is proposed. Additionally, a neural network-based algorithm for cutting load measurement is presented, achieving an accurate load measurement. Furthermore, a traction and cutting speed adaptive control approach is proposed, including an artificial intelligence-based decision-making method for traction and cutting speed and a sliding mode control method for traction and cutting speed with disturbance rejection. This approach enables a precise and adaptive speed control for the coal mining robot. Regarding the problem of cutting trajectory planning and tracking control, the precise cutting trajectory planning thought is proposed, incorporating geological data and historical cutting data into a cutting trajectory planning model. The precise cutting trajectory tracking control thought is proposed, and an intelligent interpolation algorithm-based cutting trajectory tracking control method is given, achieving a high-precision trajectory planning and accurate tracking control for the coal mining robot. Considering the “position-attitude-velocity” collaborative control problem, the intelligent optimization idea of "position-attitude-velocity" collaborative control parameters is proposed, which utilizes an improved particle swarm optimization method based on multi-system constraints to optimize the coordinated control parameters, resulting in intelligent and efficient operation of the coal mining robot. The in-depth investigation of these five key technologies for intelligent coal mining robot provides some valuable insights for accelerating the development of high-performance, efficient, and reliable intelligent coal mining robot.

Under the carbon peaking and carbon neutrality strategy, biomass has attracted much attention due to its characteristics of regeneration, low pollution and zero carbon emissions. The imperfects of biomass, such as the loose structure and low energy density, can be effectively solved by briquetting, and the resulted fuel pellets can be used as a substitute for fossil fuels, which is of great significance for the construction of new energy system. In the paper, the influencing factors of the hot briquetting process of biomass were summarized, and the evolution behavior and binding mechanism of biomass particles during the hot briquetting process were analyzed and discussed. Biomass briquetting process mainly includes cold briquetting and hot briquetting. Compared with cold briquetting process of biomass, hot briquetting with lower energy consumption can produce the biomass fuel pellets with higher quality. The moisture content (4%−15%) of the raw biomass has greater influence, the briquetting temperature (70−150 ℃) has relatively smaller effect on the density of the fuel pellets, and the briquetting pressure (60−130 MPa) and the particle size ( < 2.5 mm) of the raw material show the different impact on the density of the fuel pellets from different biomass. During the hot process, cellulose mainly plays the role of supporting skeleton, hemicellulose and lignin play the role of binder. In the microcosmic process of hot briquetting process, the inertia movement and subsequent viscoelastic-plastic deformation of the biomass particles occur and the mechanical interlock is formed between the particles. The brittle particles are broken and the natural viscous components are released, and thus, the bridge linkage between the particles is formed under the integrated effects of moisture, temperature and pressure. Mechanical interlocking and bridging reduce the distance between biomass molecules and promote the generation of intermolecular forces. Based on the above-mentioned mechanism of the hot briquetting of biomass, the quality of the resulted fuel pellets can be improved by biomass component adjustment, biomass blending or hydrothermal pretreatment. In the future, the molecular dynamics simulation method will be used to investigate the biomass briquetting process to obtain the molecular bonding mechanism of biomass components, which is conducive to further exploring the hot briquetting mechanism of biomass, and provide important guiding significance for the preparation of fuel pellets and molding materials from biomass.

The shape memory effect of alloy microwire with Fe replacing Ga based on Ni-Mn-Ga alloy microwire was analyzed. Ni-Mn-Ga-Fe alloy was prepared by vacuum tungsten arc melting furnace and the parent alloy was prepared by a high vacuum precision melt drawing equipment. The effects of Fe doping on the phase, the martensite transition behavior, and shape memory effect were studied by EDS, DSC, XRD and DMA. The results show that the Ni-Mn-Ga-Fe alloy microwire shows the mixed phase of tetragonal martensite phase and face-centered cubic austenitic phase. The step ordering heat treatment was used for the microwire. The microwire was treated by step-by-step step ordering heat treatment, the ordered heat treatment can effectively reduce the internal defects of the microwires, release the internal stress, refine the internal grains of the microwire, shrink the lattice volume, improve the compactness of the microwire, and make the martensite twin interface more straight and easier to move, and improve the elongation of the microwire.The one-way shape memory test of the prepared Ni-Mn-Ga-Fe alloy microwires is carried out at 258 K, after stretching to 350 MPa and unloading to 0 MPa. The strain recovery rate is 78.75% after the microwires are heated to the austenite state. The one-way shape memory test of the ordered heat-treated Ni-Mn-Ga-Fe alloy microwires is carried out at 289 K, and the strain recovery rate reaches 100%. The ordered heat-treated ternary Ni-Mn-Ga alloy microwire and Ni-Mn-Ga-Fe alloy microwire are stretched under constant stress at 126 MPa and 240 MPa, respectively. The two-way shape recovery ability of the two microwires can reach almost 100%, but the phase transition width of the alloy microwire during deformation, namely the elastic strain energy storage is more than that of the ternary alloy microwire. The addition of Fe makes the mechanical properties of the alloy microwires higher than that of the traditional ternary shape memory alloy microwire; compared with Ni-Mn-Ga alloy microwires, the martensitic transformation temperatures of Ni-Mn-Ga-Fe alloy microwires in as-prepared and heat-treated states increase by 6.0 K and 11.5 K respectively, and the thermal hysteresis decreases by 6.7 K and 1.5 K respectively. In practical applications, Ni-Mn-Ga-Fe shape memory alloy may be more widely used due to its small thermal hysteresis, high martensitic transformation temperature and large strain recovery rate.

The nuclear thermal propulsion (NTP) boasts advantages such as high specific impulse, substantial thrust, and extended operating time, giving it a clear edge in deep space exploration and orbital maneuvers. To fully harness the potential of NTP, a comprehensive system performance analysis is crucial to ensure reliability and efficiency under various operational conditions. This study provided an overview of the historical development and current status of nuclear thermal propulsion system analysis programs, both nationally and internationally. It also conducted an in-depth analysis of programs utilized in projects such as NERVA and SNTP. Building on an examination of historical international program advancements and current research requirements, system performance analysis is categorized into three primary components:steady-state performance design and optimization, steady-state off-design performance analysis, and transient performance analysis. Based on the independently developed program for analyzing nuclear engine systems (PANES) at Institute of Nuclear and New Energy Technology, Tsinghua University, an integrated NTP system analysis program framework based on "flow network-heat network" was proposed. The one-dimensional flow network model employed a concept similar to the staggered grid commonly used in computational fluid dynamics (CFD). It separately handled the momentum conservation equation in the resistance/inertia segment and the continuity and energy conservation equations in the capacitance segment. The thermal network model was solved based on the solid energy equation considering heat capacity. Coupled calculations of the thermal network and flow network were achieved by considering heat exchange in the capacitance segment of the flow network. Specifically, a point reactor model based on backward Euler (BE) or Crank-Nicolson (CN) time discretization formats was established to facilitate the calculation of power produce processes. To enhance the understanding and optimization of turbine performance, a turbine model was developed, employing iterative methods to determine mass flow based on turbine inlet parameters, pressure ratios, and characteristic curves. Additionally, to accurately simulate centrifugal pump behavior, a centrifugal pump model based on Suter curves was implemented. The integration of these models provides a comprehensive approach for considering and effectively designing and optimizing the performance of turbine and pump components within the NTP system. This work lays a crucial foundation for further research and application of NTP system design methods, paving the way for future advancements in space exploration and offering exciting prospects for upcoming space missions.

This paper delves into the impact of abnormal echoes at the rail head on flaw recognition resulting from the central 70° probes on rail flaw detection (RFD) vehicles. Using B-scan data showcasing such 70° probe echoes near a transverse crack at the rail base on a rail flaw detection calibration track, this study elucidated the ultrasonic propagation path through analysis, theoretical calculations, and software simulation. The results identified these echoes as ghost echoes, originating from ultrasonic emissions by the central 70° probe and subsequently reflecting from the transverse crack at the rail base. Meanwhile, considering the characteristics of such ghost echoes, this paper presents practical suggestions for flaw recognition applications under the scenario of 70° echoes near a transverse crack at the rail base and a weld seam. The characteristics of such 70° probe echoes summarized in this paper can improve flaw recognition accuracy and reduce false alarming rates in rail detection.

Anthocyanidin reductase is one of the key enzyme involved in the synthesis of flavonoids. In order to explore the structure of ANR gene, ANR enzyme expression pattern and flavonoid content under drought stress and their correlation, a HrANR gene identified from RNA-seq data of sea buckthorn was screened and analyzed by bioinformatics soft, the expression patterns of HrANR gene in different tissues and of flavonoid contents in leaves were performed. The results were as follows: (1) The ORF of HrANR gene was 1 017 bp, which encoded 338 amino acids. It was a stable hydrophilic protein, and the homologous protein had significant family and genus characteristics. (2) HrANR gene was expressed in roots, stems and leaves of sea buckthorn under drought stress, but the expression trends were different, with an increase followed by a decrease and then an increase in roots, a continuous decrease in stems, and an increase followed by a continuous decrease in leaves. (3) The flavonoid contents in leaves of sea buckthorn under different levels of stress showed a trend that first increased continuously and then decreased slightly, increased to the highest point after rehydration. The above results indicated that the expression of HrANR gene and the changes of flavonoid content were closely related to the drought resistance of sea buckthorn. The flavonoid content in leaves was positively correlated with drought stress at the beginning of drought stress and negatively correlated with drought stress under severe stress. (4) Leaf expression, stem expression and flavonoid content of HrANR gene were negatively correlated (Pleaf= -0.751, Pstem= -0.934) and root expression was positively correlated with flavonoid content (Proot= 0.444). The above results indicate that the expression of HrANR genes and changes of flavonoid content in sea buckthorn are closely related to drought resistance, and it provides a reference for elucidating the drought resistance mechanism of sea buckthorn.

Under the national “dual carbon” goal, how to reduce the carbon emissions of the coal industry and achieve carbon storage has become an urgent problem to be solved. The coal industry is the producer of high carbon fossil energy and the main carbon emission source provider. In the process of production and consumption, the accumulation of bulk solid waste, the formation of large goaf and a large amount of CO2 emissions are the bottlenecks that restrict the sustainable development and utilization and the green and healthy development of the coal industry. In order to solve the problem of carbon dioxide storage and mine waste consumption, the bulk solid waste disposal, high-value solid waste utilization, CO2 storage and goaf utilization were organically combined, the concept of carbon dioxide backfill was put forward, and three types of dioxide backfill were defined from the perspective of carbon sink capacity assessment. ① The basic theories involved in the transportation process of CO2 filling slurry and mineralization reaction process are analyzed. The mathematical equations for each process and calculation formulas for carbon sequestration amount are provided. The influence of factors such as temperature and humidity on the mineralization reaction mechanism, carbon sequestration amount, and strength of the backfill body are pointed out. ② The carbonation technological approaches, CO2 sequestration capacity of major alkaline industrial solid wastes and enhancing measures of CO2 mineralization are summarized. On this premise, two types of CO2 backfill materials preparation technique based on direct carbonationand or indirect carbonationand are presented, which can fulfill the criterion of mine backfill in fluidity, solidification characteristics and strength. ③ To solve the problem of decomposed CO2 escaping during CO2 backfill, two technical paths of strip roadway paste backfilling and intermittent backfilling behind packed hydraulic support have been proposed. The former sequesters decomposed CO2 by constructing backfilling bodies with multiple through holes in the weak backfilling strip, while the latter uses packed hydraulic support and chain self-filling baffling to construct backfilling strips in longwall goaf to control roof caving and form a CO2 physicochemical storage space. ④ In order to evaluate the carbon balance effect of CO2 backfill, the calculation boundary of carbon footprint and carbon sequestration in CO2 backfill was defined according to the life cycle method, including the stages of raw material mining, transportation, processing, injection, solidification, etc. Then, the carbon footprint and carbon sequestration in the CO2 backfill process were sorted out, and factors such as the source, dosage, loss, and conversion of CO2 were considered. Next, the calculation methods of carbon footprint and carbon sequestration in the processes of raw material transportation, filling slurry preparation, underground injection and filling were given. The research results are expected to reduce the energy consumption and cost of CO2 storage, and have far-reaching significance for green coal mining and sustainable development and utilization.

目的 基于头颈部CTA结合临床特征，探讨中高海拔地区伴头颈部动脉粥样硬化的TIA患者1年内发生脑梗死的危险因素，并构建风险预测模型，评价其预测效能。 方法 采用回顾性分析，连续纳入2018年1月—2021年9月青海省第五人民医院收治的TIA患者（居住海拔2000～3000 m），所有患者均经头颈部CTA证实存在动脉粥样硬化斑块。随访1年，根据是否发生脑梗死分为未梗死组与梗死组。首先对两组患者的临床资料和头颈部CTA检查结果进行单因素分析，筛选出有意义的变量，再通过多因素logistic回归分析脑梗死的独立影响因素，构建TIA后1年内发生脑梗死的风险预测模型以绘制ROC曲线。 结果 初步纳入患者111例。随访中出现9例失访，1例于外院放置颈动脉支架，1例发生硬膜下血肿，均不符合最终的纳入标准。最终纳入100例患者，其中梗死组26例，未梗死组74例。单因素分析显示梗死组ABCD2评分高于未梗死组[4.00（3.75～5.00)分 vs. 3.00（2.00～4.00）分，P=0.004]；梗死组高血压分级＞1级（69.23% vs. 41.89%，P=0.022）、具不稳定斑块（88.46% vs. 67.57%，P=0.039）、血管中重度狭窄（53.85% vs. 12.16%，P＜0.001）和不稳定斑块累及血管数＞1支（69.23% vs. 31.08%，P=0.001）的患者比例高于未梗死组，以上差异均有统计学意义。logistic回归分析显示，高血压分级＞1级、 ABCD2评分偏高及血管中重度狭窄是TIA后1年内发生脑梗死的独立危险因素，其风险预测模型为：P=1/[1+exp（﹣4.782+1.407×高血压分级+0.574×ABCD2评分+2.734×血管狭窄程度）]。该模型预测脑梗死的AUC为0.848（95%CI 0.763～0.933），敏感度为92.31%，特异度为70.27%。 结论 高血压分级＞1级、ABCD2评分偏高及血管中重度狭窄是中高海拔地区伴头颈部动脉粥样硬化的TIA患者1年内发生脑梗死的危险因素，三者联合构建的预测模型对脑梗死有良好的预测价值。 Abstract: Objective Based on the head and neck CTA combined with clinical characteristics to explore the risk factors of cerebral infarction within 1 year in patients with TIA from middle and high altitude areas with head and neck atherosclerosis, and construct a risk prediction model to evaluate its predictive effectiveness. Methods A retrospective analysis was performed to continuously select TIA patients (living at an altitude of 2000-3000 m) admitted to the Fifth People’s Hospital of Qinghai Province from January 2018 to September 2021. All patients were confirmed to have atherosclerotic plaques by CTA with head and neck. The patients were followed up for 1 year and divided into the non-infarction group and the infarction group according to whether there was a cerebral infarction. Firstly, the clinical data and CTA test results of the two groups of patients were analyzed by univariate analysis to screen out meaningful variables. Then, the independent influencing factors of cerebral infarction were analyzed by multivariate logistic regression, and the risk prediction model of cerebral infarction within 1 year after TIA was constructed to plot the ROC curve. Results A total of 111 patients were initially included. During follow-up, 9 cases were lost to follow-up, 1 case had carotid artery stenting in other hospital, and 1 case had subdural hematoma, all of which did not meet the final inclusion criteria. Finally, 100 patients were included, including 26 patients in the infarction group and 74 patients in the non-infarction group. Univariate analysis showed that the ABCD2 score of the infarction group was higher than that of the non-infarction group[4.00 (3.75-5.00) points vs. 3.00 (2.00-4.00) points, P=0.004]. The proportion of patients with hypertension grade>1 (69.23% vs. 41.89%, P=0.022), unstable plaque (88.46% vs. 67.57%, P=0.039), moderate to severe stenosis of vascular (53.85% vs. 12.16%, P1, high ABCD2 score and moderate to severe stenosis of vascular were independent risk factors for cerebral infarction within 1 year after TIA. The risk prediction model was P=1/[1+exp (-4.782+1.407×hypertension grade+0.574×ABCD2 score+2.734×vascular stenosis degree)]. The AUC value of this model was 0.848 (95%CI 0.763-0.933), the sensitivity was 92.31% and the specificity was 70.27%. Conclusions The risk factors for cerebral infarction within 1 year in TIA patients with head and neck atherosclerosis at middle and high altitude areas are hypertension grade>1, high ABCD2 score and moderate to severe stenosis of vascular. The prediction model constructed by the combination of these three factors together has good predictive value for cerebral infarction.

In order to prevent major acid drainage pollution accidents, this study aims to improve the accuracy of acid production potential evaluation of mine rocks in the prediction of acid drainage. Specifically, this paper introduced existing calculation methods of acid-producing potential, and then determined the acid-producing mineral contents in some sulfur minerals and coal gangue samples by three-step sequential extraction method, which is then compared with the traditional method of calculating the maximum acid-producing potential by measuring total sulfur. Results show that: 1) the acid-producing potential of coal gangue is dependent on the mass percentage content of each acid-producing sulfur and the corresponding unit acid value; 2) except for sample SC, the acid-producing potential calculated by acid-producing sulfur content is lower than(with different degrees) the acid-producing potential predicted by total sulfur. The sulfur in the sample SC is mainly arsenopyrite sulfur, which has a higher acid value per unit than pyrite sulfur, resulting in a higher acid potential calculated by SC sample than predicted by total sulfur; 3) the three-step sequential extraction is suitable for samples with iron and copper sulfides as the main sulfur minerals; 4) when other sulfide components increase and blank samples are unevenly mixed, the results will be disturbed to some extent. This research provides evidences to justify the evaluation of accurate acid production potential of coal gangue in mining area.

The process steps of intelligent ventilation in mines were proposed, which could make the ventilation system more orderly and controllable. The process of intelligent ventilation in mines was divided into six process sections according to the production process, namely perception monitoring, analysis and diagnosis, intelligent decision-making, scheme approval, remote centralized control and joint control, and execution feedback, which included a total of 24 specific process steps. The input and output elements of each process step and the functional logical relationship between the process steps were clarified. According to the concept of “overall plan of the mine ventilation system+key refinement of the mining air area”, the scheme for implementing the intelligent ventilation process of the entire mine system and two refined intelligent ventilation process application scenarios for the coal mining and excavation working faces were proposed. The intelligent ventilation process steps of the mine were integrated into specific application scenarios. In order to achieve intelligent ventilation application scenarios, the overall architecture of the mine intelligent ventilation system was optimized based on the logical layering concept. The mine intelligent ventilation control platform consisting of hardware driver layer, functional module layer, computing processing layer, data storage layer, and data acquisition layer was planned and designed. The four key process sections of intelligent ventilation involved ten key process sections,which were ventilation perception monitoring, analysis and diagnosis, intelligent decision-making, remote centralized control and joint control. The ten key process steps included monitoring and perception of air volume and wind speed, online monitoring of ventilation resistance, analysis of air volume and pressure in the entire air network, identification and identification of disaster sources, calculation of dynamic air demand in mines, diagnosis of ventilation system faults, decision-making of on-demand air volume control plans, decision-making of emergency air control plans, unmanned remote air control, and unmanned emergency air control. The current technological status of the ten key process steps were summarized and analyzed, and the technical implementation paths for the ten key process steps were proposed. Through iterative upgrades of various intelligent ventilation key technologies, the mine ventilation system was ultimately achieved to be in the stable, reliable, safe, controllable, efficient, energy-saving, and emergency disaster reduction operation state throughout its entire lifecycle.

The steeply dipping coal seam is one of the main forms of coal storage in China. It is widely and regionally distributed. According to incomplete statistics, twenty-six provinces, autonomous regions and municipalities directly under the central government are involved in the mining of such coal seams, with abundant reserves, large production and high production concentration in the central and western regions. It shows diversity and complexity in terms of the conditions of existence, with different regions having different coal formation periods and different tectonic control processes, forming diverse and complex mining conditions and giving rise to different mining technology requirements. The mining of steeply dipping coal seam is technically difficult. The asymmetry of the movement and damage of the peripheral rock in the mining area affected by the inclination angle of the coal seam is obvious, and the difficulty of the stability control of the support system and equipment, the matching and coordination of the “three machines”, the layout and support of the mining roadway, and the safety guarantee of the “human-machine” environment at the working face has increased significantly, which seriously restricts the safe and efficient mining of the mine. This has seriously restricted the improvement of safe and efficient mining. The regional economic demand for the mining of steeply dipping coal seam is strong. This kind of coal seams and the production of more concentrated areas are mostly seen in the coal industry-based resource cities, the economic structure is relatively single, the safe and efficient development and utilization of coal resources for the regional energy supply, people’s livelihood, economic stability has the role of the bottom of the pocket, the demand is urgent. For a long time, mining technologies for the steeply dipping coal seam changes focus on solving the “difficult” and “need” contradiction. In the coal mining methods and techniques, strata control theory and technology, complete sets of equipment development and application of the three aspects of continuous improvement, innovation, development, to achieve the transformation from non-mechanized to fully-mechanized mining, the level of safety and production efficiency has increased dramatically, the personnel labor intensity has decreased dramatically, and the operating environment has improved significantly. In the mid-1990s, Lvshuidong Coal Mine of Sichuan Coal Industry Group Limited Liability Company successfully realized longwall fully-mechanized mining in steeply dipping coal seam with medium mining height for the first time, breaking through the "forbidden zone" in this filed. Under this demonstration, the three pioneering engineering practices of longwall fully-mechanical mining of steeply dipping coal seam with thick mining height, steeply dipping coal seam with large mining height, and longwall fully-mechanical mining of steeply dipping coal seam with thin mining height in pseudo-inclination have been successful successively, which innovated the non-linear limiting arrangement of the working face and the way of adjusting the slanting, established a multi-dimensional interactive control mode of the system stability of the “bracket-surrounding rock”, and researched and developed the “support and stability and heavy weight, high-strength and light-weight, safe and reliable, and matching synergistic” complete set of equipment of the working face, which has achieved good results, and the scope of application of the comprehensive mechanized mining technology has further been widened. At the same time, there are still many key scientific problems and technical bottlenecks that need to be broken through in the mining of steeply dipping coal seams, resulting in a large gap between the intelligence level and that of the flat/gently inclined coal seams. Research on the mining dynamics of coal and rock bodies in inclined bedded coal beds, revealing their control mechanisms on the disaster of the surrounding rocks in the mining field, and realizing quantitative characterization need to be further strengthened. It is necessary to further clarify the multi-dimensional dynamic process and law between the system of “rock-bearing structure - mining equipment group”, improve the theoretical and technological basis of “multi-dimensional dynamic multi-objective synergistic control of equipment and surrounding rock”, and realize the transformation and application of the technology. On the basis of breakthroughs in scientific issues, we will carry out systematic technological innovation and research and development of coal mining methods, mining techniques, rock formation control, and complete sets of equipment, so as to crack the bottleneck of the constraints on the double enhancement of “safety and efficiency” in the mining of steeply dipping coal seams, and make the upper limit of the inclination of the steeply dipping coal seams for comprehensive mechanized mining extend upward under the prerequisite of reliable technological safeguards, so as to lay the foundation for the realization of automated and intelligent mining.

In order to solve the problem of grasping failure or missing grasping due to the change of target gangue position and posture caused by belt slip, deviation and belt speed fluctuation of belt conveyor when the gangue sorting robot sorts gangue, an improved ORB-FLANN efficient matching method of gangue recognition image and sorting image is proposed. An improved ORB feature point detection method is proposed to detect the feature points in the recognition image and sorting image of coal gangue, so as to realize fast detection of image feature points; An improved FLANN matching algorithm is proposed to match the image feature points to achieve efficient matching between the recognition image of coal gangue and the sorting image. Aiming at the problem of long time and low repetition rate of traditional ORB method for coal gangue image feature detection, an improved ORB feature detection method is proposed to improve the speed and repetition rate of image feature point detection; Aiming at the low accuracy of traditional FLANN matching method for coal gangue image matching, an improved FLANN matching method integrating PROSAC algorithm is proposed to eliminate the wrong feature matching point pairs and improve the accuracy of image matching. The method, SURF feature matching method, HU moment invariant matching method, SIFT feature matching method and ORB feature matching method are applied on the experimental platform of the double mechanical arm truss type gangue sorting robot independently developed by the team to carry out gangue matching experiments under different belt speeds, scales and rotation angles. The results show that the matching rate of the method in this paper is 98.2%, and the matching time is 141 ms. It has the characteristics of high matching rate, good real-time performance and strong robustness, It can meet the requirements of efficient and accurate matching of gangue recognition image and sorting image.

Objective Trace elements are an important factor affecting the water quality of karst surface waters. Aquatic photosynthetic organisms can absorb and remove harmful elements in the process of photosynthetic metabolism. However, little research has been conducted on the absorption effect and removal potential of trace elements by different aquatic photosynthetic organism community structures. Methods This study was conducted at the Puding Karst Ecosystem National Observation and Research Station, which constructed a vegetation-soil-groundwater-surface water simulation ecosystem consisting of five types of land use: bare rock land, bare land, cultivated land, grassland and shrub land. Among them, the surface aquatic ecosystem was taken as the research object to carry out research on the removal potential and control mechanism of trace elements by the composition of aquatic photosynthetic organism community structure. Results Results showed that (1) The surface water chemistry parameters and aquatic photosynthetic biomass were significantly affected by seasonal changes and land use types; (2) The concentrations of Cr, Mn, Co, Ni, Fe and Zn varies significantly in different aquatic photosynthetic ecosystems, and the absorption and removal of Mn, Co, Ni, Fe, and Zn by the planktonic-submerged coexistence system were better than those of a single planktonic system; (3) The formation of a highly dissolved inorganic carbon (DIC) environment in surface water bodies was promoted by the restoration of natural vegetation (shrublands and grasslands) in karst areas, which was conducive to the growth of submerged plants, simultaneously increasing the impact on Mn, Co, Ni, Fe and Zn removal potential in surface water bodies. Conclusion This understanding will contribute to research on the regulatory mechanism of trace elements in surface water by the structure of aquatic photosynthetic organisms in karst areas.

[Objective] To address the issue of the highly integrated internal structure of the EP2002 valve system, which hinders internal fault injection, a metro train braking simulation control system that accurately reflects the functioning mechanism of the EP2002 braking system is designed. The system is intended for fault simulation and personnel training in metro train braking systems. [Method] The air circuit structure and operating mechanism of the EP2002 valve system are introduced, and the overall scheme of the metro train braking simulation control system based on EP2002 is elaborated separately for the electrical and pneumatic components. Using AMESim simulation software, common and emergency braking experiments are conducted to simulate the air circuit of the EP2002 braking system and the metro train braking simulation control system respectively, and the consistency of their braking characteristics is verified. [Result & Conclusion] The overall scheme of the metro train braking simulation control system based on EP2002 utilizes basic air circuit components to construct an equivalent unit circuit with properties identical to the EP2002 valve. For the more complex parts of the air circuit, a mathematical model based on chamber air filling and venting is employed using time-stepping simulation in the software for equivalence. The control unit based on the STM32F107 microcontroller is used for monitoring and controlling the pneumatic section, as well as managing communication between various equivalent EP2002 valve units. The metro train braking simulation control system adopts networking structure similar to EP2002 braking system, with multiple equivalent EP2002 valve units interconnected through a CAN bus and vehicle bus to establish a braking simulation control system based on the EP2002 braking system, achieving cost-effective simulation of the entire train braking system. AMESim model simulation results indicate that the metro train braking simulation control system can maintain brake cylinder pressure at the target value with faster response speed and higher control precision, exhibiting external braking characteristics completely consistent with the EP2002 braking system.

[Objective] Once failures occur in urban rail transit, the need for assistance from other trains can significantly impact the subsequent train operation and passenger safety. Improper choices in the rescue path may also lead to secondary effects on already operating lines. Therefore, it is essential to study fault rescue plans based on rescue paths and organization. [Method] Existing procedures for fault rescue of urban rail transit trains are analyzed. Combining the actual operation time and process of train fault rescue, the process and operation time of train fault rescue are analyzed. The discussion includes the selection of rescue paths when a train fault occurs at different locations on a line. By considering the choice of the rescue train, the selection of rescue method, and the location for storing the faulty train, these aspects are combined to derive various fault rescue plans. Taking Shanghai Rail Transit Line 7 as example, the fault rescue plans are compared and summarized. [Result & Conclusion] The train fault rescue process is divided into four stages: fault handling, rescue preparation, rescue operation, and rescue completion. Based on the selection and combination of the rescue train, rescue method, and location for storing the faulty train, a comprehensive fault rescue plan for the entire Shanghai Rail Transit Line 7 is obtained. Through practical verification, this rescue plan can effectively avoid secondary delays, thereby enhancing the quality of metro services.

Objective To identify the effect of acute stress induced by composite factors on intestinal barrier dysfunction and explore the relevant mechanism. Methods Twenty male C57BL/6 mice (7-8 weeks old, body mass 20-22 g) were randomly divided into control group (CON group, n=10) and model group (MOD group, n=10). To establish an acute stress model of complex factors, the mice of the MOD group were given rest of 4 h, sleep deprivation of 15 h, and then followed by 3 h of noise (120 dB)/flash (2 000±500 lx) and 2 h of forced swimming (water temperature 26±1 ℃, water depth 45 cm) within 24 h. While the mice in the CON group were placed in a noiseless environment with constant temperature and humidity and normal circadian rhythm but been given no any treatment. At the end of forced swimming, the mice from the MOD group were anesthetized for blood samples and then euthanized. Serum markers of intestinal injury were detected by immunoenzyme-linked adsorption assay kit, morphological changes in colonic tissues were observed by HE staining, protein and mRNA levels of colonic tissue barrier function related molecules and inflammatory factors were detected by immunofluorescence, immunohistochemistry and RT-qPCR, and intestinal flora changes were analyzed by 16S rRNA technique. Results Compared with the CON group, the serum markers of intestinal damage, lipopolysaccharide (LPS), intestinal fatty acid binding protein (I-FABP) and Zonulin were significantly increased in the MOD group (P < 0.05). HE staining showed that intestinal tissue damage was obvious in the MOD group. The results of immunofluorescence staining and RT-qPCR showed that the levels of mechanical barrier related molecules Zona occludens 1 (ZO-1) and Occludin were obviously decreased (P < 0.05). Immunohistochemistry and PAS staining indicated the number of chemical barriers associated goblet cells, and expression of mucin2 (Muc-2), antimicrobial peptide regenerating islet derived-3γ (Reg3γ) and regenerating islet derived-3β (Reg3β) were notably reduced (P < 0.05). Intestinal flora β diversity significantly changed, with harmful bacteria Bacteroidetes and Desulfovibrio significantly increased, while beneficial bacteria Rumenococcus family, norank_f_Erysipelotrichaceae, Gemella genus and Erysipelotrichaceae genus declined (P < 0.05). The levels of TNF-α, IL-6 and ROS were significantly enhanced (P < 0.05). Conclusion Acute stress of complex factors significantly induces intestinal injury and barrier dysfunction.

The hot-rolled Al-Zn-Mg-Cu system aluminum alloy was treated with single-stage solution，low temperature-long term & high temperature-short term and low temperature-short term & high temperature-long term，double-stage solution quenching systems. The effects of different solution methods on the structure and properties of Al-Zn-Mg-Cu system aluminum alloy were systematically compared and analyzed by OM，SEM，DSC，EBSD and other technical means，as well as conductivity testing methods. The results show that the selected solution quenching system will not cause the structure to overheat，and can fully dissolve the eutectic second phase of the low melting point in the structure. When 473 ℃/20 min+477 ℃/40 min two-stage solution quenching system is selected，the plate has the best solution effect and the lowest conductivity，which is 27.60%IACS，and the recrystallization degree of the structure is less than 50%. There are {112}〈111〉，{011}〈211〉，{123}〈634〉 deformation texture and {001}〈110〉 shear texture in the structure.

Meteorological factors have an impact on the operating temperature of line, and the operating temperature of line is closely related to line impedance and fault outage rate. The influence of meteorological factors on the multiple parameters of line is not fully considered when evaluating the reliability of power systems. In this context, based on weather-dependent heat balance equation of transmission line, the calculation method of line temperature considering meteorological factors and the real-time capacity model of transmission line dependent on meteorological conditions are firstly studied. And then, the impedance parameter model and the real-time outage rate model of transmission line are established, which are dependent on the line temperature. Next, a power system operation reliability evaluation method considering meteorological factors is proposed based on Monte Carlo simulation. Finally, taking the IEEE 14-bus and IEEE RTS96-bus modified systems as examples, the influence of meteorological factors on the real time parameters of transmission lines including capacity, temperature, impedance, failure rate, and on the operation reliability indices of power systems are analyzed. Case results verify the correctness of the proposed operation reliability model of transmission line and the operation reliability evaluation method of power systems considering meteorological factors.

In order to choose a suitable thawing method for Micropterus salmoides (room temperature thawing, running water thawing, saltwater thawing, ultrasonic static water thawing and ultrasonic running water thawing), this paper took Micropterus salmoides as the research subject. To investigate the effects of different thawing methods on water retention, total volatile base nitrogen (TVB-N), malondialdehyde content, peroxide value, total sulfhydryl content and Ca2+-ATPase activity of Micropterus salmoides. At the same time, the changes of texture properties such as hardness, elasticity and adhesion of fish were analyzed. The results showed that the normal temperature thaw 219 min, longest, fish water retention, lipid and protein oxidation was the most serious. Thawing water and salt water thawing time consuming 35 and 55 min, respectively, was the shorter of the normal temperature thaw, but fish water retention, protein oxidation, quality and structure characteristics of the various quality indexes such as the change was still serious. After ultrasonic static water thawing, the fish had better water retention and texture characteristics, and could effectively alleviate the oxidation of fish protein, but the lipid oxidation was more serious. Ultrasonic flow water thawing could complete the thawing of fish within 24 minutes, which was more efficient. Compared with other thawing methods, it could effectively maintain the water retention and texture characteristics of fish, and effectively delay the oxidation of fish protein and lipid. Ultrasonic thawing of frozen water, therefore, Micropterus salmoides had little effect on quality, was the most suitable thawing method.

The quasi-stationary front in Yunnan and Guizhou is one of the most important weather systems in Guizhou in winter， and it is difficult to forecast.This paper analyzes the winter climate characteristics of the quasi-stationary front in Yunnan and Guizhou and frontal rainfall characteristics of different magnitudes in Guizhou by using the daily ground conventional observation station data of five provinces （cities， districts） of Yunnan， Guizhou， Sichuan， Chongqing， Guangxi from 2007 to 2021 and the daily precipitation data of Guizhou from 08:00 to 08:00.The results show that： （1） There are 52.8 days of the quasi-stationary front weather in Guizhou in winter on average.The impact of the quasi-stationary front is most serious in January， followed by February and December.（2） In winter， the front direction of the quasi-stationary front in Yunnan and Guizhou is the most south-north type， averaging near Qujing； The second is the northwest southeast type， which is located in the west of Guizhou on average； There are few east-west types； The moderate intensity quasi-stationary front is the most and tends to occur in the early winter， the strong quasi-stationary front is the second and tends to occur in the late winter， and the weak quasi-stationary front is the least.（3） The frontal precipitation is dominated by rainfall （rain or freezing rain）.The stronger the quasi-stationary front is， the fewer the days of frontal precipitation are， and the proportion of the days of frontal precipitation increases with the weakening of the quasi-stationary front； The frontal rainfall is mainly concentrated below 5.0 mm， and the frontal rainfall probability is inversely proportional to the rainfall and is proportional to the rainfall range.When the frontal rainfall is weak， the frontal rainfall probability is unimodal with the increase of rainfall and bimodal with the expansion of rainfall range.（4） The results of EOF and REOF classification show that there are two types of frontal precipitation with different magnitudes that affect Guizhou： the frontal precipitation in the central and eastern regions is mostly in the early winter and more south-north， with moderate or weak intensity and prone to large-scale rainfall of 0.1~1.0 mm magnitude； The southwest type frontal rainfall is mostly in the late winter， and it is mostly north-south type or north-west southeast type.The intensity is strong， and the small-scale rainfall of 1.1~5.0 mm is easy to occur.（5） The climate tendency rate of the average annual rainfall in the middle-east type is negative， and the cumulative anomaly changes are roughly in the "M" shape； The climate tendency rate of annual average rainfall in the southwest type is positive， with obvious stage characteristics， and the cumulative anomaly changes are roughly "W" shaped； Both of them have quasi 4 years and quasi 8 years periodic oscillations； In recent years， the frontal rainfall in the middle-east has decreased， while that in the southwest has increased.The results can provide an important climate background for the prediction of quasi - stationary front weather in winter in Guizhou.

During operation， hydraulic turbines are continuously subjected to long-term impact from sediment-laden water flows.The combined damage from sediment erosion and cavitationerosion significantly impairs the flow components，compromising the safe and stable operation of the unit.Surface protection of the flow components by means of high-elastic polymer coatings is an economical and practical strategy.In this paper，firstly， the anti-cavitation protective polymer coatings on the surfaces of flow components were reviewed， especially research progress on polyurethane and epoxy resin coatings.Considering the important influence of the erosive and abrasive effects of sediment-laden water flows in the damage of hydraulic turbines，the research progress of polymer/ceramic composite coatings in the synergistic resistance to cavitation and erosion was reviewed； finally， the problems of polymer coatings in the protection of hydraulic turbine flow components were described.

This is an essay in the field of metallurgical engineering. The effects of crushing particle size and leaching conditions on the leaching of lithium cobalt from spend lithium-ion batteries in the citric acid environment were studied, which provided some reference for the recovery of different types of mixed spend lithium-ion batteries. The results showed that Mn， Al， Ni, Co and Li accounted for a large proportion of the contents in mixed different types of spend lithium-ion batteries. Due to the larger recovery value of Co and Li and simplify the recovery process, only Co and Li be recovered. The crushing particle size has little influence on the leaching rate of lithium cobalt in the range of -5 mm, while the leaching rate of lithium cobalt in the larger crushing particle size is not high, which may be lithium and cobalt wrapped in the middle of particles and cannot contact with the leaching solution, thus reducing the leaching effect. For mixed different types of spend lithium-ion batteries，under the conditions of -5 mm particle size, citric acid concentration 1.0 mol/L, leaching temperature 65 ℃, solid-liquid ratio 1 g/100 mL, H2O2 concentration 3%, leaching time 55 min, stirring speed 30 r/min, the lithium leaching rate of 97.86% and cobalt leaching rate of 98.01% are obtained.

ObjectiveTo examine the awareness of and responding to a nationwide road traffic safety campaign named “One Helmet, One Seatbelt” among motor vihicle riders/passengers in China. MethodsAn online questionnaire survey was conducted among e-bike or motorcycle riders/passengers and automobile drivers/passengers recruited with snowball sampling in 18 provinces, 5 autonomous regions, and 3 municipalities across China between July and August 2021 – one year after the initiation of the program. We analyzed the awareness of the campaign and the increase of helmet-wearing and seatbelt usage after the campaign among the participants. ResultsEligible responses were collected from a total of 564 participants including 314 (55.68% of the participants) e-bike/motorcycle riders, 17 (3.01%) e-bike/motorcycle passengers, 137 (24.29%) automobile drivers, and 96 (17.02%) automobile passengers. Of the 451 e-bike/motorcycle riders and automobile drivers, 91.13% (411) reported the awareness of the road traffic safety campaign and there was no significant difference in the awareness rate between the e-bike/motorcycle riders and automobile drivers (92.04% vs. 89.05%, χ2 = 1.053; P > 0.05). Among the 331 e-bike/motorcycle riders/passengers, 245 (74.02%) reported increased helmet-wearing after the implementation of the campaign and significantly more e-bike/motorcycle riders reporting increased helmet-wearing compared to e-bike/motorcycle passengers (76.11% vs. 35.29%, χ2 = 13.973; P < 0.001). Of the automobile drivers/passengers, 43.78% reported increased seatbelt usage after the campaign and the proportion of reporting increased seatbelt usage was not significantly different between the drivers and the passengers (43.07% vs. 44.79%, χ2 = 0.068; P > 0.05).ConclusionThe awareness rate of the nationwide “One Helmet, One Seatbelt” road traffic safety campaign was high among e-bike/motorcycle riders and automobile drivers; meanwhile, helmet-wearing increased in e-bike/motorcycle riders/passengers and seatbelt usage increased in automobile drivers/passengers one year after the initiation of the campaign.

Counter-flow engines are often used for aircraft slowing or separating. In order to study the interaction between the counter-flow jets and free stream at high altitudes, the rarefied flow driven by two counter-flow jets and hypersonic free stream was constructed. By the direct simulation Monte Carlo (DSMC) method, it is found that a large area of mutual interference will be formed under the condition of rarefied free stream, and there are serious unsteady flow phenomena in the interference area. According to preliminary analysis, the range and unsteady evolution of the interference area are closely related to the kinetic energy of free stream and the flow rate of counter-flow jets.

Objective To evaluate the effects of acupuncture on physical function, depression and quality of life in stroke patients. Methods A systematic search of the publicly available databases such as the Cochrane Library, PubMed, Embase, China Knowledge Network (CNKI), Wan Fang Data, VIP Database (VIP) and China Biomedical Literature Database (CBM) was conducted, and randomized controlled trials on the use of acupuncture in stroke patients from its inception to April 10, 2023 were included for the Meta analysis. Results Thirteen studies were included. The results showed that acupuncture could promoted recovery of limb function ［MD=6. 86, 95%CI (5. 63, 8. 08), P＜0. 01］, improved depressive symptoms common in post-stroke patients ［MD=-6. 95, 95%CI (-9. 32, -4. 57), P＜0. 01］, and improved patients' quality of life ［SMD=1. 83, 95%CI (1. 63, 2. 04), P＜0. 01］. Conclusion Acupuncture can not only promote the recovery of limb function, but also improve depressive symptoms common in post-stroke patients and enhance their quality of life. (目的 评价针灸对卒中患者肢体功能、抑郁症状和生活质量的干预效果。方法 系统检索the Cochrane Library、Pub Med、Embase、中国知网(CNKI)、万方数据库(Wan Fang Data)、维普数据库(VIP)和中国生物医学文献数据库(CBM)从建库至2023年4月10日公开发表的关于针灸应用于卒中患者的随机对照试验。结果 最终纳入13篇文献。结果表明, 针灸在促进患者肢体功能的恢复［MD=6. 86, 95%CI(5. 63, 8. 08), P＜0. 01］, 改善卒中后患者常见的抑郁症状［MD=-6. 95, 95%CI(-9. 32, -4. 57), P＜0. 01］, 提升患者生活质量［SMD=1. 83, 95%CI(1. 63, 2. 04), P＜0. 01］方面优于对照组。结论 针灸不仅可以促进患者肢体功能的恢复, 而且可以改善卒中后患者常见的抑郁症状, 提升患者生活质量。)

With its continuous application and promotion, filling technology, such as an ultra-long distance and special pipeline arrangement, faces an increasing demand, and the demand for the fluidity of filling material is also rising. Aiming at the large risk of blocking pipes and tubes in filling technology, the serious wear of pipelines, etc., and using modified magnesium slag (MMS) and fly ash (FA) to prepare high liquidity under different ratios of a new type of paste filling material (UH-MFPB), this paper probes this material’s early strength, liquidity, and rheological properties, and establishes the relationship between liquidity and rheological parameters. First, MMS and FA samples were prepared at different ratios of certain concentrations and cured for 3, 7, 28, and 56 days to measure their uniaxial compressive strength. The uniaxial compressive strength of a UH-MFPB sample increases first and then decreases with increasing FA content, and gradually increases with curing age. When FA content is 20%, the compressive strength of the sample reaches the maximum. At 3, 7, 28, and 56 days, the intensity was 1.335, 2.161, 6.759, and 12.104 MPa, respectively. Then, the slump and spread of fresh UH-MFPB slurry were measured. They increased with FA content, with a slump of 25.6–29.2 cm and a spread of 61–93.1 cm, showing good fluidity. Then, the rheological properties of fresh UH-MFPB slurry were measured in accordance with the Herschel–Bulkley model, and the relationship between shear stress and plastic viscosity and the shear rate was discussed, as well as the effect of FA content on rheological parameters and mechanisms. The shear stress is found to increase with the shear rate, and the viscosity decreases exponentially and then slowly with increasing shear rate. Rheological parameters (yield stress, plastic viscosity, and thixotropy) decrease with increasing FA content, and the slurry undergoes shear thickening when FA content reaches 20%. The Cross viscosity model was used to fit the viscosity curve of fresh slurry. Finally, the correlation between the fluidity and rheological parameters of fresh UH-MFPB slurry was discussed, and the yield stress was found to correlate negatively with the slump, plastic viscosity, and expansion, which were quadratic polynomials. Considering all factors, when FA content is between 10% and 30%, UH-MFPB slurry has ultra-high fluidity and high strength, which can play a good role in filling slurry transport.

In the calculation of rail flaw echo location, the rail flaw location is related to the ultrasonic propagation time in rail. The more accurate the extracted propagation time, the more accurate the rail flaw location calculation. During high speed rail flaw detection, unevenness in the vertical direction of the rail, structural differences in the detection wheel lifting unit and differences in the amount of fluid filled in the detection wheel will cause vertical jump of the detection wheel, leading to changes in ultrasonic arriving time at the rail surface of different probes and influencing flaw localization. Therefore, the paper proposes a rail flaw echo accurate localization method based on interface wave tracking technology. Taking 45° and 70°probes as examples, flaw echo localization based on interface wave tracking technology and the effectiveness of interface wave tracking technology under different pressure conditions of detection wheels are analyzed. An artificial flaw test block is designed, and flaw detection experiment is carried out and verified. The results show that interface wave tracking technology can guarantee precise extraction of ultrasonic echo time of different probes in the detection wheel(the time accuracy is 0.025 μs), and it is beneficial for rail flaw localization. In addition, based on the analysis of actual detection data of rail lines, suggestions for the application of interface wave tracking technology in flaw detection are proposed.

[Objective] The lakeshore of plateau lakes is the concentrated area of production and living in the location, the key area of ecological construction, and the typical area of change of “production-living-ecological” functions. Understanding the evolution of the “production-living-ecological” space is of great significance for the sustainable development of the concerned regions. [Methods] Based on the data from interviews and web texts, the actor network theory and NVIVO11 software were used to explore the key actors and their behaviors in the evolution of “production-living-ecological” functions of the Erhai lakeshore. [Results] (1) Since 2000, the Erhai lakeshore has experienced two periods of change, one was a gradual spatial change from living to production function, and the next was an abrupt spatial change from production to ecological function. (2) In the process of gradual spatial change, the key actor was the innkeepers, the identity of the Erhai Lake was the waterscape, and the role of the homesteads and houses was to provide commercial services. In the process of abrupt spatial change, the key actor was the local government, the identity of the Erhai Lake was the water environment, and the role of the homesteads and houses was to provide living services. (3) The gradual spatial change was due to the process of innkeepers leading other actors to form a capital tension network around the obligatory passage point (OPP) “landscape consumption of the Erhai Lake”, promoting the socially self-organized tourism development of the lakeshore; and the abrupt spatial change was due to the process that the local government instructed other actors to form a power pressure network around the OPP “ecological restoration of the Erhai Lake”, realizing the ecological restoration of the lakeshore by administrative forces. [Conclusion] The lakeshore is the focus of the game between stakeholders, based on the differentiated network formed by different key actors, resulting in alternating changes in living, production and ecological functions of the lakeshore.

The rubber blends for rubber roller were prepared with natural rubber, styrene-butadiene rubber and trans-1,4-poly(butadiene-co-isoprene) rubber, the effects of trans-1,4-poly(butadiene-co-isoprene) rubber amount on the compatibility, curing characteristics, mechanical properties, wear resistance and aging resistance of the blends were investigated. The results showed that as the trans-1,4-poly(butadiene-co-isoprene) rubber amount increased from 0 to 20 phr (mass), the crosslinking density of the blend increased gradually and curing time shortened, tensile strength increased gradually, hardness increased slightly, compression permanent set showed a downward trend, and wear resistance improved. The compatibility of the three rubbers was good, and the dispersion of filler and aging resistance of the blending rubber were improved.