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Porous Ti-Nb alloys with different contents of Nb elements were prepared by vacuum sintering technology. The effects of Nb element contents on pore morphologies， porosities， microstructures， elastic modulus， and wear resistances of porous Ti-Nb alloys were investigated. The results show that with the ascent of Nb element contents， the pore morphology of porous Ti-Nb alloys does not change significantly， and the porosities increase gradually. The porous Ti-Nb alloys are mainly composed of α-phase and β-phase， in which， due to the β-phase stabilizing effect of Nb elements， the volume fraction of the β-phase in the alloys increases significantly with the increase of the Nb element content， and the compressive strength and elastic modulus of the alloys decrease gradually. The wear resistance of porous Ti-Nb alloys in simulated body fluid （SBF） is mainly related to the volume ratio of β-phase to α-phase. When the volume ratio of β-phase to α-phase exceeds 61.7/38.3， the wear resistance of the alloy gradually improves.

Marine geothermal energy is rich in China but have not been well developed. Integrating marine geothermal energy with other marine resources is crucial for ensuring China’s energy security, realizing the carbon peak and carbon neutrality goals, strengthening the country’s energy sector, building a new energy system, and promoting island and deep-sea development. This study reviews the current status of marine geothermal energy utilization in China and abroad, analyzes the challenges faced by China in marine geothermal energy utilization, and clarifies the key development directions of marine geothermal energy utilization in China: (1) core technologies and key equipment for the exploration and development of marine geothermal energy, (2) core technologies and key equipment for marine geothermal energy utilization, and (3) marine geothermal energy industry and industrial chain construction. Moreover, the study expounds on the staged development goals and proposed two typical models for marine geothermal energy utilization in China: integrated development with offshore heavy oil and with marine natural gas hydrate. Future development strategies are further proposed: (1) coordinating marine function zoning and incorporating marine geothermal energy and offshore oil and gas blocks into unified national planning; (2) pinpointing the distribution of marine geothermal energy in South China Sea and its overlapping advantages with other marine resources; (3) accelerating research on core technologies and key equipment for the development and utilization of marine geothermal energy; (4) increasing financial support and providing subsidies and preferential fiscal and tax policies to fully mobilize the enthusiasm of enterprises; and (5) conducting pilot tests in marine geothermal energy enrichment areas to explore the demonstrations of integrated development with other marine resources.

The combined exposure to environmental pollutants can result in unanticipated adverse effects on human health, and how to compare and assess these effects has always been a matter of great concern for the international community. Currently, several prevalent methods for assessing combined exposure risks in the field of human health risk assessment primarily encompass the hazard index (HI) method, the point of departure index (PODI) method, the margin of exposure (MOE) method, and the relative potency factor (RPF) method. The review summarizes the application of these methods to the cumulative risk assessment of combined exposure to the same class of chemicals with the same toxic mechanism, primarily focusing on pesticides such as organophosphorus pesticides, pyrethroids, carbamates, and neonicotinoids, as well as typical compounds intimately related to human production and life, including organophosphorus flame retardants, per- and poly-fluoroalkyl substances, and bisphenols. Furthermore, progress in the application of physiologically based pharmacokinetics models to human health risk assessment has been introduced, which might provide more options for risk assessment of combined exposure to multiple chemicals, and help to provide insights for further exploration and establishment of more systematic and scientific approaches to human health risk assessment.

AIM: To investigate the effect of long non-coding RNA-HIF1A-AS1(lncRNA HIF1A-AS1)on the chemotherapy sensitivity of vincristine(VCR)-resistant in retinoblastoma(RB)cells by regulating the expression of hypoxia-inducible factor-1α(HIF-1α).METHODS: The human RB VCR-resistant cell line SO-RB50/VCR was established, expression of lncRNA HIF1A-AS1 in SO-RB50 and SO-RB50/VCR cells were detected by reverse transcription-quantitative real-time PCR(RT-qPCR); inhibition of lncRNA HIF1A-AS1 expression or simultaneous overexpression of HIF-1α in SO-RB50/VCR cells, and then median inhibitory concentration(IC50)of VCR and cell proliferation and apoptosis were detected in SO-RB50/VCR cells; the protein expressions of HIF-1α, multidrug resistance associate protein(MRP)and P-glycoprotein(P-gp)were measured by Western blot.RESULTS: Compared with SO-RB50 cells, the expression levels of lncRNA HIF1A-AS1 and HIF-1α protein in SO-RB50/VCR cells were increased(P

Background/Aim. High-grade glioma (HGG) is an interstitial cell-derived primary tumor of the nervous system. The current guidelines for the diagnosis and treatment of glioma recommend the maximum safe range of tumor resection for treatment methods. Adjuvant concurrent chemoradiotherapy is recommended after surgery, followed by six cycles of single-drug chemotherapy, temozolomide. Evaluation of the early efficacy of concurrent chemoradio-therapy after HGG surgery, especially for patients with a high risk of recurrence, is a crucial step in enhancing the treatment efficiency for patients diagnosed with HGG. In this study, we investigated the clinical utility of magnetic resonance (MR) spectroscopy (MRS) in assessing the early curing impact of concurrent chemoradiotherapy following HGG surgery. Methods. A total of 50 patients with incomplete resection or suspected residual postoperative HGG, treated in the radiotherapy department of our hospital between January 2016 and June 2021, were selected for routine concurrent chemoradiotherapy. Conventional MR imaging and MRS were performed one week prior to treatment and one month after treatment to assess changes in specific brain metabolites. All 50 patients were followed up for 6 to 12 months. Based on the follow-up results, the patients were divided into two groups: the tumor recurrence group and the tumor suppression group. One month after the end of the treatment, the differences in levels of brain metabolites between the two groups were analyzed using MRS. Results. The levels of N-acetylaspartate (NAA) and creatine (Cr) increased after radiotherapy, while choline (Cho) peak value, and Cho/Cr, NAA/Cr, and Cho/NAA ratios decreased compared to pre-treatment levels. There were statistically significant differences in the NAA peak value, and Cho/Cr, and Cho/NAA ratios in the tumor enhancement area before and after treatment (p < 0.05). There were also statistically significant differences in Cho/Cr ratio in the peritumoral edema area before and after treatment (p < 0.05). Conclusion. After concurrent chemoradiotherapy, MRS can be used to detect early metabolic changes in the tumor enhancement and peritumoral edema areas of HGG.

This paper addresses the problem of multi-source survey data sharing in power system engineering by proposing two improved methods: a survey data sharing method combined with differential privacy and a permission change method based on attribute encryption. The survey data sharing method integrated with differential privacy achieves effective cross-professional and cross-departmental data sharing while ensuring data security by introducing multi-discriminator architecture and dynamic noise adjustment. To reduce the computational and communication overhead when user permissions change during survey data sharing, the attribute encryption-based permission change method supports dynamic changes in user permissions. The effectiveness of the proposed methods has been validated through targeted experiments in different scenarios. The work in this thesis provides a new solution for dynamic sharing of survey data in power network engineering. It contributes to the digital transformation of power network projects.

In this work, normal manufacture of a B-bearing steel was hampered by cracks in steel. In order to control these cracks, the formation mechanism has been examined through a comprehensive analysis of crack morphology, element segregation, high temperature mechanical properties, and precipitates. The high-temperature thermoplastic capabilities of the steel were found to be reduced by boron nitride particles precipitated at grain boundary. This led to the formation of a brittle zone in the straightening zone of the continuous casting process, which in turn caused cracks. Based on the formation mechanism of these cracks, the cracks were successfully controlled by adding an appropriate amount of Ti element to the steel and reducing the charging temperature of the heating furnace.

In order toinvestigatethe synergistic effectof Cl－ and HCO3－ onthecorrosion behavior of 316L stainlesssteel， the effectsof differentCl－ concentrations(0， 0.0300， 0.0515and 0.070 0 mol/L) andHCO3－concentrations (0.01， 0.03 and 0.05 mol/L) on the electrochemical corrosion behavior of 316L in groundwater environment simulation fluid in Liaohe Oilfield were evaluated by electrochemical impedance spectroscopy (EIS) and cyclic polarization curve technology.Moreover， the corrosion morphology of the specimen was characterized using a metallographic microscope， and the product composition was determined using X-ray photoelectron spectroscopy (XPS).Results showed that as the Cl－ concentration increased， the capacitive arc diameter decreased，the dispersion index decreased，the pitting corrosion potential decreased，and the corrosion situation intensified.In comparisons， as the HCO3－ concentration increased， the diameter of the capacitive arc increased， the dispersion index increased， the pitting corrosion potential increased， and the corrosion of 316L slowed down.This was due to the fact that Clwould destroy the passivation film on the surface of 316L， and HCO3－ would react with the substrate to form a dense FeCO3 protective film.

Speckle type BTB/POZ protein (SPOP) may have cancer promoting or inhibiting effects. At present, the role of SPOP in hepatocellular carcinoma (HCC) has rarely been studied. In this study, to investigate the effects of SPOP in HCC and elucidate the underlying molecular mechanisms of its relationship with genes, differentially expressed genes (DEGs) were classified through RNA sequencing. The gene ontology analysis and Kyoto Encyclopedia of Genes and Genomes functional pathway analysis were used to further predict the function of DEGs after the overexpression of SPOP. The biological function of SPOP-regulated alternative splicing events in cells is comprehensively assessed. The Cancer Genome Atlas database and Gene Expression Omnibus dataset were performed to evaluate the correlation between SPOP and HCC progression. Due to SPOP overexpression, 56 DEGs in the HCC related pathway were further identified. The results showed that SPOP overexpression facilitated the cell proliferation and changed the gene expression profiles of human normal hepatocytes. SPOP-regulated alternative splicing events were involved in pathways associated with cellular processes, metabolism, environmental information procession, organismal systems, and so on. In conclusion, SPOP may potentially exhibit tumor-promoting effects, necessitating further investigations to unveil its molecular mechanisms comprehensively.

Objective·To study the effect of rhubarb administration on the balance between intestinal flora and the body.Methods·Wistar rats were randomly divided into 4 groups (n=8), which were given extractions of rhubarb 0.1 g/kg (low dose group), 2.5 g/kg (medium dose group), 4.5 g/kg (high dose group) and normal saline (control group) by intragastric administration for 5 d, and the daily change of fecal water content of rats was observed. Gas chromatography/time of flight mass spectrometry (GC/TOFMS) approach was used to detect the metabolites in serum, colon tissue and fecal of rats on the 5th day of administration. Principal component analysis (PCA) and partial least squares discrimination analysis (PLS-DA) were used to analyze the differences of metabolites between different dose groups and the control group. The metabolites with statistical significance were obtained by t-test.Results·The water content of rat feces in the dose group gradually increased with the time and dose after rhubarb administration. Compared with the control group, 28, 18 and 20 differential metabolites were obtained in serum, colon tissue and fecal samples from different dose groups, which showed significant changes (P

To achieve large-scale development of triboelectric nanogenerators (TENGs) for water wave energy harvesting and powering the colossal sensors widely distributed in the ocean, facile and scalable TENGs with high output are urgently required. Here, an elastic self-recovering hybrid nanogenerator (ES-HNG) is proposed for water wave energy harvesting and marine environmental monitoring. The elastic skeletal support of the ES-HNG is manufactured using three-dimensional (3D) printing technology, which is more conducive to the large-scale integration of the ES-HNG. Moreover, the combination of a TENG and an electromagnetic generator (EMG) optimizes the utilization of device space, leading to enhanced energy harvesting efficiency. Experimental results demonstrate that the TENG achieves a peak power output of 42.68 mW, and the EMG reaches a peak power output of 4.40 mW. Furthermore, various marine environment monitoring sensors, such as a self-powered wireless meteorological monitoring system, a wireless alarm system, and a water quality monitoring pen, have been successfully powered by the sophisticated ES-HNG. This work introduces an ES-HNG for water wave energy harvesting, which demonstrates potential in marine environment monitoring and offers a new solution for the sustainable development of the marine internet of things.

Gas adsorption experiment with coal particles is a basic means to study the gas flow mechanism of coal matrix. In order to explore the influence of coal particle shape on coal gas adsorption law, a constant temperature and pressure adsorption experiment was designed to obtain the adsorption characteristics of coal samples with four particle sizes under different gas pressures. Based on the gradient diffusion theory of free gas density in coal matrix, the mathematical models of constant pressure adsorption of cylindrical and spherical coal gas were established respectively, and solved by finite difference method, and the simulation results were verified by experimental data. It is found that the simulation results obtained by considering the coal particles as spherical or cylindrical have a good match with the experimental results, which proves the accuracy and reliability of the gradient diffusion theory of free gas density in coal matrix. The diffusion coefficient increases with the increase of coal particle size. The influence of gas adsorption pressure on the diffusion coefficient of micropore is small, and the diffusion coefficient of difference of surface area between the two shapes.

Currently, research on improving the efficiency of coal roadway heading mostly focuses on improving heading equipment, with less consideration given to the working procedures and personnel allocation of coal roadway heading. Maintaining a harmonious and stable human-machine relationship is the key to ensuring the efficiency of coal roadway heading. Taking the 2404 air inlet roadway of 8404 working face in Madaotou Coal Mine as the engineering background, and considering the human-machine matching relationship, an optimization plan for coal roadway heading operation is proposed. The coal cutting support process of the anchor excavator has been optimized. A support system for the heading roadway with non-aligned top and side anchor spaces has been proposed. This means that after two consecutive cycles of footage, the anchor heading unit is not retracted. The top anchor is 300 mm ahead of the side anchor to save roadway support time. The numerical simulation results indicate that the stress field of non-aligned support with top and side anchor bolts in space is not significantly different from that of aligned support with top and side anchor bolts in space. It verifies the reliability of the non-aligned support system with top and side anchor bolts in space. The process of coal roadway heading is optimized through the multi-process parallel operation. The task volume of each process is calculated to optimize the personnel allocation related to each process. The engineering application results show that after optimizing the coal roadway heading operation based on the human-machine relationship, the daily cycle number increases from 10 to 15, the monthly footage increases from 300 m to 450 m, the worker efficiency increases from 0.1 m/worker to 0.14 m/worker, and the cycle is reduced from 80 minutes to 44.6 minutes. It significantly improves the efficiency of coal roadway heading.

Located in the Heilongjiang (Amur) River in north-east Asia, spanning four countries, plays a crucial role as an international border river, and its meteorological changes significantly impact the variation in water resources in the basin. This study utilizes daily average temperature and precipitation data from 282 meteorological stations in the Heilongjiang (Amur) River Basin and its surrounding areas for the period 1980–2022. The analysis employs spatial interpolation, change point testing, and model construction prediction methods. The results indicate a significant increasing trend in both overall temperature and precipitation changes within the Heilongjiang (Amur) River Basin. At the spatial scale, the annual warming rate increases gradually from the southeastern coastal region to the northwestern plateau region, while the rate of precipitation increase decreases from the southern area towards its surroundings. Temporally, the warming amplitude during the growing season decreases gradually from east to west, and the trend in precipitation changes during the growing season aligns with the overall annual precipitation trend. During the non-growing season, the warming trend shows a decrease in the plains and an increase in the plateau, while precipitation increase concentrates in the central and southern plains, and precipitation decrease predominantly occurs in the northwestern plateau region. Temperature and precipitation change points occurred in the years 2001 and 2012, respectively. In precipitation prediction, the Long Short-Term Memory (LSTM) model exhibits higher accuracy, with R (Pearson correlation coefficient) and NSE (Nash-Sutcliffe efficiency coefficient) values approaching 1 and lower NRSME values. This study provides a research foundation for the rational development and utilization of water resources in the Heilongjiang (Amur) River Basin and offers valuable insights for research on climate change characteristics in large transboundary river systems.

In this paper, the composition of protein, amino acids, fatty acids, minerals, vitamins and other nutrients in bactrian camel milk was discussed, and the research progress of the biological activities of camel milk and its enzymolysis products such as hypoglycemic, antibacterial, antiviral and antioxidant activities was summarized.

The WHO has declared the outbreak of COVID-19 a public health emergency of international concern. Oral pre-examination and triage work is one of the central tasks of epidemic prevention and control in dental medical institutions. This article introduces the development of pre-examination and triage management in the Outpatient Department of Peking University School and Hospital of Stomatology in epidemic prevention and control. Based on the experience in diagnosis and management, gradually explore the management of pre-examination and triage that conforms to the characteristics of the dental profession. By clarifying the organization and management of pre-examination and triage work in outpatient clinics, establish pre-examination and triage work systems, job responsibilities, and formulate pre-examination of dental outpatients according to patient risk classification. The primary screening process and the tertiary screening plan, various emergency plans and the treatment process for special patients, strengthen the pre-inspection staff's study of prevention and control policies and regulations, and gradually form the dental clinic pre-examination score Diagnosis management system. At the same time, it is also seen that in the normalization of epidemic prevention and control for several years, the development of oral pre-examination and triage has become more standardized and more information technology has been used to help fight the epidemic. (新型冠状病毒肺炎疫情为“国际关注的突发公共卫生事件”。口腔预检分诊工作是口腔医疗机构疫情防控的中心工作之一, 本文介绍了疫情防控中北京大学口腔医院门诊部预检分诊管理的发展。在借鉴国内外综合医院预检分诊管理经验基础上, 逐渐摸索符合口腔专业特性的预检分诊管理, 通过明确门诊预检分诊工作组织管理, 建立预检分诊工作制度、岗位职责、根据患者风险分类制定口腔门诊患者预检初级筛查流程和三级筛查方案、各类应急预案及特殊患者的处置流程, 加强预检工作人员对防控政策法规学习、院感防控知识培训考核演练等逐步形成口腔门诊预检分诊管理体系。同时, 常态化疫情防控工作中, 口腔预检分诊的发展更加规范化, 更多地运用信息技术助力疫情防控。)

In this review, the mechanism of emulsion formation and the influence of physical, chemical, biological and other environmental factors on its stability were summarized, and the demulsification method in the industrial application of hydroenzymatic extraction of peanut oil was prospected.

At present, the research on unmanned mine trucks mainly focuses on specific control methods such as path tracking and aided decision-making for driving safety. The research is insufficient to support the unmanned operation of the whole mining area transportation system. To solve this problem, an overall design scheme for unmanned transportation system in the mining area is proposed. The system is divided into three layers of cloud control center, edge side and intelligent terminal. The system mainly comprises a mine truck automatic driving system, a mining area unmanned transportation cloud control dispatching platform, an unmanned transportation simulation system, a remote emergency takeover system, a health management system, a collaborative operation management system and a positioning/communication system. The automatic driving system of mine trucks has the function of intelligent management of a single vehicle. It realizes the functions of obstacle perception, intelligent decision-making, path planning, high-precision positioning and precise control. The cloud control dispatching platform is used for unified dispatching management. It realizes collaborative automatic loading and unloading of unmanned mine trucks, electric shovels and bulldozers. It also realizes collaborative mixed operation of unmanned mine trucks and various manned auxiliary operation vehicles. The unmanned transportation simulation system simulates different dispatching operation modes according to the real-time environment of the mine. It forms an optimal schedule scheme to guide actual production. The remote emergency takeover system realizes remote control of the unmanned mine truck in extremely dangerous scenarios. It ensures that the vehicle can be taken over urgently when the automatic driving system of the mine truck encounters a failure. The health management system realizes the functions of equipment self-inspection, fault diagnosis, maintenance result reporting and health state evaluation through the relevant sensors installed at the terminal of the unmanned mine truck. The collaborative operation management system assists the unmanned mine truck to complete the operation together under the condition of ensuring the safety of the driver and the vehicle. It is realized through the software and hardware systems installed on the manned mining equipments, engineering equipments and auxiliary production equipments. The positioning/communication system is the communication channel connecting the cloud control center and the intelligent terminal. It supports multiple communication modes such as 4G/5G/Mesh, and realizes V2N (vehicle-network), V2V (vehicle-vehicle) and V2I (vehicle-infrastructure) communication.

Large-scale high-energy physics experiments generate scientific data at the scale of petabytes or even exabytes, requiring high-performance data IO for processing. However, in large computing centers, computing and storage devices are typically separated. Large-scale data transfer has become a bottleneck for some data-intensive computing tasks, such as data encoding and decoding, compression, sorting, etc. The time spent on data transfer can account for 50% of the entire computing task. The larger the amount of data accessed, the more significant this cost becomes. One attractive solution to address this problem is to offload a portion of data processing to the storage layer. However, modifying traditional storage systems to support computation offloading is often cumbersome and requires a broad understanding of their internal principles. Therefore, we have designed a flexible software framework called XkitS, which builds a computable storage system by extending the existing storage system EOS. This framework is deployed on the EOS FTS storage server and offloads computational tasks by invoking the computing capabilities (CPU, FPGA, etc.) on FTS. Currently, it has been tested and applied in the data processing of the Large High Altitude Air Shower Observatory (LHAASO), and the results show that the time spent on data decoding using the computable storage technology is half of that using the original method.

Skin wound healing is a continuous and complex process affected by many factors. Growth factors play an important role in the process of wound healing. Local application of growth factors can significantly promote wound healing. However, the degradation and time dependence of growth factors require appropriate delivery systems to help them play a role in wound healing. In recent years, wound dressing products with hydrogels as matrix materials or main components have shown obvious advantages in promoting wound healing. By modifying the hydrogel or combining it with other factors or materials that are beneficial to wound healing, the healing effect can be further enhanced. This review will introduce the research status of growth factors and hydrogels based on natural biological materials in skin wound repair and review the effects and research progress of the combination of growth factors and hydrogels in skin wound healing.

Geogrid reinforcements can effectively improve the pullout capacity of anchor plates, but the failure mechanism and influencing factors during the uplift process need to be further investigated. In this paper, a series of uplift tests was carried out on horizontal anchor plates in sand to investigate their pullout characteristics, and the influence of various factors was analyzed, including sand density, anchor embedment depth, and number of geogrids and their locations. The particle image velocimetry (PIV) technology was used to explore the deformation and failure mechanism of the sand around anchor plates. The results show that for the pullout capacity of an anchor plate is significantly enhanced by one layer of contact-type geogrid, and the reinforcing effect is better than that with non-contact geogrid. This phenomenon is associated with mobilized friction of the geogrid and the increased weight of sand within the failure surface. When two layers of geogrids are installed, the lower geogrid plays a dominant role in restricting the lateral soil deformation and homogenizing the stress distribution, and the contribution of the upper geogrid is relatively low. Whether geogrids are applied or not will alter the deformation mechanism at the anchor-sand interface. With geogrid reinforcement, the failure surface converges inward, and the shear strain distribution is more uniform.

ObjectiveTo investigate the prevalence of allergic and infectious diseases in children， and to assess the influence of indoor and outdoor environmental factors on these two common diseases in children.MethodsA questionnaire was used to investigate the prevalence of allergic and infectious diseases in 140 children of 7 years old in Laizhou Bay， Shandong Province. Logistic regression was used to analyze the associations between indoor and outdoor environmental factors and children’s allergic and infectious diseases， respectively.ResultsThe prevalence of previous eczema and other allergic diseases for the past year in children was 37.9% and 15.0%， respectively， and the prevalence of infectious diseases for the past year was 35.7%. As for allergic diseases， eye irritation due to outdoor air （OR=2.977； 95%CI： 1.407‒6.296） and nose irritation due to outdoor air （OR=5.147； 95%CI： 1.272‒20.827） were the risk factors for previous eczema in children. Indoor musty taste increased the risks of urticaria （OR=4.306； 95%CI： 1.062‒17.454） and previous eczema （OR=3.853； 95%CI： 1.080‒13.743）. The use of cockroach killers indoors increased the risk of rhinitis （OR=6.102； 95%CI：1.297‒28.697）. As for infectious diseases， having outdoor pollution sources increased the risk of gastrointestinal infection （OR=4.937； 95%CI： 1.050‒23.216）， and the use of mosquito coils and clothing mothproofing agents increased the risks of respiratory （OR=6.333； 95%CI： 1.397‒28.714） and gastrointestinal infections （OR=3.218； 95%CI： 1.074‒9.644）， respectively. However， we did not find associations between indoor passive smoking and allergic or infectious diseases.ConclusionExcept outdoor passive smoking， all the other indoor and outdoor environmental factors increase the risks of children’s allergies and infectious diseases.

doi：10.3969/j.issn.1672⁃6731.2021.12.015

For low Earth orbit (LEO) satellites, solar panel is a firstly key device to convert the solar radiation into the electric power to supply the energy consume. However, the solar array is always suffering from the power degradation due to the harsh space environments. To meet the power balance in the end life of the spacecraft, attitude determination and control system (ADCS) plays an important role in the solar panel direction to change the solar energy input. Here, the solar cell performance parameters from an LEO satellite running on a dawn-dusk Sun synchronous orbit (SSO) are investigated. A yaw maneuver application is presented to satisfy the electric power supply (EPS) risk of the solar cell current decrease. Validated in the space operation, the results have shown that in the yaw mode, the EPS output is improved and the solar cell current is averagely enhanced more than 10% when the orbit incidence is 35°. The yaw maneuver is applied to the state of health (SOH) management with a better power supply. The solution can be widely and usefully taken into account to increase the solar array output for a near-Earth satellite in the risk of the power shortage.

The test of mine unmanned vehicle has problems of great danger, long test time, high test cost and narrow test coverage. In order to solve the above problems, the simulation system of unmanned mine vehicle based on parallel control theory is studied. The system adopts key technologies such as mine vehicle dynamics modeling, high-fidelity scene reconstruction, and virtual sensor modeling. The system realizes the functions of comprehensive deduction of the unmanned driving algorithm, system integration reliability test, mining area production prediction simulation, and virtual and actual interactive parallel deduction. The main step of dynamic modeling of the mine vehicle is divided into two parts: vehicle model building and visual scene creation. The vehicle dynamic model is associated with the virtual scene. The simulation data generated by the vehicle model is used for driving the vehicle in the virtual scene to move in real-time. In view of the complex and irregular characteristics of the large-scale open-pit mine scene, the high-precision 3D model data of the mine is obtained by means of UAV aerial mapping and laser radar 3D scanning. Based on the virtual micro polygon geometry technology, high pixel virtual texture technology, and 3D scene real-time rendering technology, a high-fidelity virtual 3D scene is constructed. The virtual sensor mainly comprises virtual laser radar, virtual millimeter wave radar, virtual inertial navigation device and virtual vision camera. The virtual sensor is carried on the virtual mine car. It is responsible for generating virtual data information in a simulated mining area scene, and sending the data to the automatic driving controller for processing. Based on the simulation system, single-vehicle test, multi-vehicle scheduling test and intelligent scheduling algorithm test can be carried out. The dynamic virtual-reality interaction between on-site vehicles and virtual vehicles can be tested. The system is used to provide a verification platform for stable transportation of the whole mining area, deduction simulation of complex intersections and optimal decision of intelligent scheduling algorithm. The system ensures the efficiency and safety of unmanned driving test and accelerates the upgrading of unmanned driving technology in the mining area.

Triboelectric nanogenerators (TENGs) possess significant attributes, such as a simple structure, high energy conversion efficiency, and ease of fabrication, rendering them crucial for powering mobile and distributed low-power electronic devices. In this study, a multilayer spring TENG with a cushion layer structure is proposed that enhances the output performance of the basic TENG structure. The fundamental topology of the energy harvesting circuit is chosen based on the electrical performance parameters of the generator and optimizes the selection of each electronic component in the actual circuit. This allows the small-size TENG (2 cm3) to have a high storable power density (5.45 mW m−2). Finally, the fabrication method of the small-size TENG and how to choose suitable electronic components based on the intrinsic electrical parameters of the TENG were summarized. This work provides valuable guidance for designing and fabricating self-powered IoT node devices.

Oat bran was used as a substrate, and red yeast rice powder was added to provide fermented bacteria for mixed fermentation.The effective lipid-lowering ingredients in the mixture were used as evaluation index, and the fermentation process conditions (fermentation time, fermentation water pH, and amount of red yeast rice powder) were optimized by a single factor experiment.The results showed that the optimal fermentation time was 72 h, the pH of the fermentation water was 6.7, and the amount of added Monascus powder was 10 g.Under this condition, the contents of monacolin K, Monascus pigment, and β-glucan in the fermentation product were 3.76 mg/g, 27.58, and 3.31%, respectively.Compared with the raw mixture of oat bran and red yeast rice powder, monacolin K and Monascus pigments increased by 38.2% and 23.0% respectively, while β-glucan only decreased by 41.2%.The fermentation product contains three kinds of high-fat lipid-lowering ingredients at the same time, and it is meaningful for the comprehensive utilization of oat bran and the development of lipid-lowering functional foods.

Auxetic metamaterials and structures have excellent mechanical properties such as shear resistance, impact resistance, fracture resistance, energy absorption and vibration isolation, permeability variability, synclastic curvature in bending, etc. Auxetic metamaterials have broad application prospects in the fields of aerospace, navigation, mechanical automation, biomedicine, national defense and military and textile industry. Based on the deformation mechanism of auxetic metamaterials and structure, the physical models of re-entrant mechanism, rotating rigid mechanism, chiral/antichiral mechanism, fibril/nodule mechanism, miura-folded mechanism, buckling-induced mechanism, helical auxetic yarn structure were reviewed. These models can be widely applied in various engineering applications such as light laminated plates, fluid transportation and yarn to improve their properties. Finally, prospects to the upcoming challenges and progress trends of auxetic metamaterials and structures are made.It is pointed out that the application of negative Poisson’s ratio effect can help compensate the change of volume and area under the deformation of uniaxial loading. Then the shock resistance of turbine blade, antenna and car suction box can be improved. As a result, this review can provide benefits for the development of auxetic metamaterials.

The power demand of large electric-wheel mine-used trucks fluctuates greatly. It has high requirements for the backup power during acceleration and the energy recovery capacity during braking. The traditional hybrid vehicle adopts the parallel power supply method of a generator set and a single power battery. However, this method is difficult to meet the vehicle’s dual requirements for peak power and energy. In order to solve the above problem, a control scheme of electric driving system for large electric wheel mine-used truck is designed, and an energy cooperative control strategy based on the combination of power following and bus voltage regulation is proposed. In the energy control process, the generator set and battery set are used as the main energy source to follow the target demand power, the super capacitor is used as the auxiliary energy source, and the DC bus voltage is regulated by alternating the work of super capacitor and generator set. Hence, the truck can automatically select the suitable bus voltage regulation mode according to the driving conditions. Considering the limitation of the maximum charging capacity and the battery life, a method is proposed in which the super capacitor is responsible for the circuit energy recovery and slowly transfers energy to the battery according to the remaining power of the super capacitor. The simulation results of the extreme driving conditions of a specific truck show that the control scheme ensures that the truck has sufficient driving power and improves the efficiency of the electric driving system. The scheme reduces the number of repeated charging and discharging of the lithium battery, which is helpful to extend the lithium battery life. Moreover, the scheme ensures the stability of the DC bus voltage when the high power fluctuates, which improves the reliability of the electric driving system.

Modified suction caisson is a new type of suction foundation for offshore wind power engineering. Model tests were carried out to investigate the variation of cumulative rotation angle and its influencing factors of the regular suction caisson (RSC) and modified suction caisson (MSC) under horizontal cyclic loading. The cyclic loading mode includes one-way cyclic loading and variable-amplitude cyclic loading. The experimental results showed that the cumulative rotation angle of the RSC and MSC under horizontal cyclic loading mainly occurs within the first 200 loading cycles. The cumulative rotation angle was found to increase with the increase of cyclic loading amplitude and the number of loading cycles. However, the increasing rate of cumulative rotation angle decreases with the increase of loading cycle number. The relationship between the cumulative rotation angle and the number of loading cycles can be well fitted by a power function. By using Leblanc method and Miner’s rule, the cumulative rotation angle of the suction caisson foundation under long-term variable-amplitude cyclic loading was transformed into that under constant amplitude cyclic loading and then can be estimated. It was found that when the loading amplitude increases step by step, the predicted cumulative rotation angle of the RSC and MSC obtained by using the Leblanc method and Miner’s law is slightly higher than the measured model test results, indicating that the sequence and amplitude of cyclic loading have a certain influence on the cumulative rotation angle of the suction caisson foundation. In addition, the influence of cyclic loading on the ultimate bearing capacity of suction caisson foundation was studied and it was found that the ultimate bearing capacities of the RSC and MSC after cyclic loading are higher than those before cyclic loading. The research results can provide a basis for the design of the suction caisson foundation of offshore wind power.

Daniil Kharms — a distinguished representative of the post-revolutionary avant- garde — was rediscovered in Russia in the 1990s. Chinese scholars began the study of his literary heritage in 2010 after a number of Kharms’ works had been translated into Chinese. Today, Kharms studies have become one of the most relevant trends within Chinese Slavic studies. This paper aims to examine Chinese interpretation of the core philosophical and aesthetic features of Kharms’ poetics in comparison with Russian scholarly interpretations and to analyze the mechanisms of reception of Kharms’s poetry and philosophy in China. Chinese scholars relate Kharms’ artistic techniques to the idea of the helplessness of a human being in the face of ontological problems. In general, Chinese scholars share an opinion that the originality of Kharms’ poetics meets the requirement of the new artistic style characterized by deconstruction of causality and the shift of the space-time continuum. The new state of art corresponds to the logic of human knowledge: within the process of renunciation (negating the negation itself), the new knowledge develops out of the opposite side of the old knowledge, which explains why the avant-garde is eternal.

Accurate picking of the first arrival of microseisms is the prerequisite for the estimation of source location. The traditional manual picking method is inefficient and time-consuming. The short time average long time average (STA/LTA) method, commonly used in automatic picking, has low picking accuracy for low signal-to-noise ratio signals. To address the above problems, a random forest-based automatic picking method of microseismic first arrival is proposed. Firstly, this study extracts the amplitude, energy and amplitude ratio of adjacent moments of microseismic data as features and mark each sample with feature categories. Secondly, a random forest model is constructed to identify microseismic first arrivals. Thirdly, the random forest model is used to calculate the probability of each test sample belonging to a certain category, and the first data sampling point with a probability of no less than 0.5 is defined as the microseismic first arrivals sampling point. In this experiment, microseismic monitoring data in deep boreholes of coal mine roadways is used. The results show that as the number of decision trees reaching 137 and the maximum depth reaching 6 in the random forest algorithm, the accuracy of the method for classifying microseismic data samples could reach 98.5%, and the average picking error for first arrivals of microseismic is 23.1 ms. Therefore, this method is better than the method of STA/LTA in terms of picking accuracy.

Long non-coding RNAs (lncRNAs) larger than 200 nucleotides in length are eukaryotic RNAs, and do not encode proteins. lncRNAs are considered to be important regulators in many biological processes in plants. In this review, the latest advances in the roles of lncRNAs in rice were reviewed, and functions of lncRNAs were further summarized and classified. lncRNAs play crucial roles in tolerance to biotic and abiotic stresses such as disease, drought, heat, cold, heavy metal, and starvation of nitrogen and phosphorus in rice. In addition, lncRNAs also regulate various growth and development processes in rice. Finally, the prospect and challenges of rice lncRNA function research in future were proposed. This review will not only help us quickly grasp the frontiers of lncRNAs functional research progresses, but also propose suggestions and ideas for the directions of further lncRNA research in rice.