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The rapid growth of the urban rail transit industry has resulted in a surge in the volume of operational data generated by urban rail trains. However, traditional full-data storage methods have become inadequate in handling the escalating demands for data processing and storage. To address this, this paper presents an innovative optimization strategy that utilizes the data hopping technology for data processing and storage. This strategy aims to significantly reduce processing demands for urban rail train operational data, minimizing the occupation of storage resources, by comparing data from adjacent time sequences to accurately identify and store characteristics of data changes. In subsequent site experiments, the proposed approach achieved a 97.5% reduction in data processing demands and a 97% saving in storage space, while ensuring data security and stability. The study outcomes not only support the endeavor to effectively ease the burden on data transmission and storage, but also provide a robust data foundation for the intelligent operation and maintenance of urban rail transit.

In order to improve the core power density of liquid metal reactors, plate-type fuel assemblies are typically used, which have obvious advantages in heat transfer capacity. For the low Prandtl number fluid, the RANS turbulence model-based CFD method needs to be modified by inserting the turbulent Prandtl number model. This paper investigated the turbulent Prandtl number model for the turbulent heat transfer of liquid metal flow in a narrow rectangular channel. First, the existing turbulent Prandtl number models were summarized and classified as the local turbulence Prandtl number model and the global turbulence Prandtl number model. They were evaluated based on the experimental data. The results showed that the prediction results of each model are not ideal. Then, a typical numerical example was used to analyze the temperature field and flow field in the narrow gap of a narrow rectangular channel. It was shown that the entire flow region only includes the near-wall region and the transition region, and the transition region accounts for the main proportion. A semi-empirical local turbulence Prandtl number model was obtained by solving the turbulent transport equation, and the unknown coefficients were determined iteratively with the experimental data. The error was controlled within ±20%. Finally, the applicability of the newly proposed turbulent Prandtl number model was explored, and the results showed that it has good applicability for the different runner sizes and different liquid metal types. This study can provide a reference for the numerical simulation of turbulent heat transfer of metal liquid in the narrow rectangular channel.

Objective To report the clinical and pathological features of 4 patients with oculopharyngodistal myopathy type 1 (OPDM1) caused by CGG repeat expansion in the 5'untranslated region (5'UTR) of LRP12 gene. Methods and Results This study included 4 patients with OPDM1 who were admitted to Peking University First Hospital from January 2008 to August 2023. All 4 patients presented with weakness of eyes closed, dysarthria, dysphagia, facial muscle weakness and muscle weakness mainly involving distal muscles. None of 4 patients had restricted eye movements. Two of the patients had ptosis (Case 1 and Case 2). Serum creatine kinase (CK) levels were mildly to moderately elevated (190- 1211 U/L) in 4 patients. Three patients (Case 1, Case 2 and Case 3) underwent lower extremity muscle MRI which showed varying degrees of fatty infiltration, with the soleus and tibialis anterior muscles being worst affected. Skeletal muscle biopsies in all 4 patients showed rimmed vacuoles with muscular dystrophy‑like pathological changes. Immunofluorescence staining revealed p62 ‑ positive and ubiquitin ‑ positive intranuclear inclusions in all 4 patients. Genetic testing revealed that all 4 patients carried CGG repeat expansion in the 5'UTR of the LRP12 gene. Conclusions Most OPDM1 patients start with weakness in the distal extremities of both limbs and dysarthria. The involvement of muscles in the lower extremities is asymmetrical, and the involvement of tissues and organs other than muscles is not obvious. The remaining clinical phenotype and pathological features are consistent with other subtypes of OPDM.

Short tandem repeat (STR) is a component of the human genome, the number of repeats of STR is prone to change during DNA replication, and when it exceeds a certain threshold, it will lead to the occurrence of diseases, most of which involve the nervous system. With the rapid development and wide application of the third generation long read long sequencing technology, more and more neuromuscular diseases have been confirmed to be related to STR variation. This article reviews the clinical and mechanism research progress on STR‑related neuromuscular diseases, so as to provide guidance for clinical research.

In a vehicle intelligent operation and maintenance system, the ground data processing platform needs to collect vehicle operational status data in real time for vehicle monitoring and health status analysis. To ensure the security of the transmitted data, this paper proposes a secure data transmission solution based on the application scenario of in-vehicle status data transmission, combining the features of chinese national cryptographic algorithms SM4 and SM9.This solution utilizes SM4 to achieve fast encryption of the plaintext in-vehicle status data, ensuring the confidentiality, integrity, resistance to attacks, and resistance to interference of the data. Additionally, SM9 is used to encrypt the key transmission of SM4, ensuring the confidentiality, resistance to attacks, and non-repudiation of the keys. Experimental results show that compared with other solutions, the proposed solution not only guarantees the integrity, confidentiality and non-repudiation of vehicle-to-ground data transmission, but also exhibits good versatility and high efficiency. It is applicable for various types of vehicles, data processing platforms and communication network environments, featuring high throughput, low resource consumption and extensive application in the future.

With the development of information and control technology, fully automatic operation system (FAO) has been widely adopted in the construction of new subway lines. Since the main line operating vehicles under FAO mode do not have driver posts, the dispatchers at the control center need to monitor the running status of all trains on the line in real time to ensure the correct operation of the trains. According to the characteristics of FAO mode , this paper designs a train dispatching system based on big data architecture. The system collects status data of train subsystems and processes and analyzes them based on big data framework,which realizes real-time status monitoring of vehicles on the whole line; and provides human-computer interaction interface for remote control, which meets the requirements of metro operation dispatcher for vehicle running status monitoring. The system has been verified by the third party security assessment, and its stability and availability meet the FAO line operation requirements.

Calcareous sand is a natural foundation material for ports, airports and some civil buildings in ocean areas. Through the one-dimensional compression creep test of calcareous sand and the analysis of its micro-structure, it was found that the surface pore area decreased after creep and showed a dispersed distribution. In addition, the characteristics of instantaneous deformation, rapid deformation and attenuation deformation of the sample during the test were highly correlated with the particle size. The relative particle breakage rate and mass fractal dimension improved based on fractal theory were used to describe the degree of particle breakage after creep. The relationship between the decay of fractal dimension and creep with time, as well as the linear relationship between the fractal dimension of macroscopic mass and the fractal dimension of microscopic surface was obtained. On this basis, the fractal fracture behavior of calcareous sand with a single particle size group during long-term creep was analyzed at multiple scales, and the corresponding macro and micro cross-scale correlation was studied. The development of particle breakage and the variation of microscopic pores during creep were obtained. This study proved the rearrangement, crushing and grinding behavior of calcareous sand particles in the creep process, and revealed the creep mechanism of calcareous sand.

ObjectiveTo examine the effect of improving diatom DNA extraction by glass bead - vortex oscillation method.MethodsThe DNeasy PowerSoil Pro kit was used as control, two plant DNA extraction kits with different principles （New Plant genomic DNA extraction kit and Plant DNA Isolation kit） and one whole blood DNA extraction kit （whole blood genomic DNA extraction kit） were selected to extract diatom DNA from lung tissue and water sample of the same drowning case. The combination of mass ratio of glass beads with different sizes and vortex oscillation time was designed, and the optimal DNA extraction conditions were selected with the addition of glass beads oscillation. The extracted products of the conventional group and the modified group were directly electrophoretic and detected by diatom specific PCR. Finally, all the extracts were quantified by qPCR, and the Ct values of different groups were statistically analyzed.ResultsWhen the frequency of vortex oscillation was 3 000 r/min, the optimal combination of DNA extraction was vortex oscillation for 4 min, and the mass ratio of large glass beads to small glass beads was 1∶1. The DNeasy PowerSoil Pro kit was used as a reference, and the Ct value of 10 mL water sample was greater than that of 0.5 g tissue. The Ct values of the other three kits used for plant DNA extraction decreased after the glass beads-vortex oscillation method was used, and the Ct values of the tissues before and after the improvement were statistically significant （P

Diatom detection is an important method for identifying drowning and throwing corpses after death and inferring the drowning sites in forensic examination of corpses in water. In recent years,high-throughput sequencing technology has achieved rapid development and has been widely used in research related to diatom taxonomic investigations. This paper reviews the research status and prospects of high-throughput sequencing technology and its application in forensic diatom detection.

In order to solve the problem of low oxygen in the first working face 5-20101 of Qinglongsi Coal Mine, in this paper, combined with the working face mining and the surrounding basic situation, it is found that the influence of atmospheric pressure change, low temperature oxidation of the residual coal in goaf, water and gas displacement in goaf and positive pressure fan ventilation in tail-lane are the important reasons for low oxygen in working face. Some technical measures have been taken, such as establishing the monitoring system of spontaneous combustion, reducing the negative pressure of mine ventilation, strengthening the sealing of air leakage above and below the mine, inerting the floating coal in the goaf, improving the progress of the working face and injecting nitrogen into the goaf, so as to effectively solve the problem of low oxygen in the mining process of the working face and ensure the safe production of the mine.

Objective To investigate the effects of DCLK1 on the proliferation, migration and invasion of glioma cells and their mechanisms. Methods The mRNA and protein expression of DCLK1 in glioma tissues and glioma cell lines U87 and A172 were detected by RT-qPCR, immunohistochemical staining and Western blot. sh-DCLK1 and the corresponding negative control (sh-Con) were transfected into glioma cell lines U87 and A172 by Lipofectamine 2000 to silence DCLK1 expression. The effects of DCLK1 knockdown on the proliferation, migration and invasion of glioma cells were analyzed by MTT assay and Transwell assay. The effects of DCLK1 knockdown on the expression of TGF-β/Smads signaling pathway-related proteins TGF-β1, p-Smad2 and p-Smad7 in glioma cells were detected by Western blot. U87 cells transfected with sh-DCLK1 or sh-Con were injected into the subcutaneous neck of BALB/c nude mice, the tumor volume and weight were measured. Results Compared with normal adjacent tissues and normal glial cells, the mRNA and protein expression levels of DCLK1 were significantly increased in glioma tissues and cells (P < 0.001). Compared with sh-Con group, the proliferation, migration and invasion abilities, and the expressions of TGF-β1, p-Smad2 and p-Smad7 proteins of glioma cells in sh-DCLK1 group were significantly decreased (P < 0.01; P < 0.001); in addition, tumor volume and weight of sh-DCLK1 group were significantly reduced in vivo (P < 0.001). Conclusion DCLK1 knockdown could inhibit the proliferation, migration and invasion of glioma cells, which may be related to the inhibition of TGF-β/Smads signal activity.

During postulated severe accident, large amount of hydrogen-vapor mixture will be released into the containment and inflammable gas mixture may form. Once the gas will be ignited, the generated pressure loads can jeopardize the integrity of the internal structures. As the local accumulation of high content hydrogen related much to the stratification and erosion mechanism, it is therefore of interest whether a stratification of gas layers will form within small containment. In this study, a stratification/erosion experiment is performed and the criteria under which the steady stratification will be destroyed by steam jet discussed. Then the simulation method is validated by the experimental data. At last, several severe accident scenarios for Chinese SMR performed and one of them is adopted for containment hydrogen CFD analysis. It is shown that high content of hydrogen will form in the upper part of the containment, and clear gas stratification will form, such stratification will be enhanced due to the condensation effect of steel containment wall.

This study investigates the factors influencing consumer acceptance of certain types of innovation in handicraft products. Another aim of the article is construct/scale development applicable to handicrafts because our study collected scale items from other studies and tried to develop constructs applicable to handicraft products. The descriptive analysis through a quantitative cross-sectional consumer survey was applied along with cluster analysis for consumer market segmentation following the acceptance of certain types of innovations. Eight factors were discovered through EFA. The construct scores for authenticity innovation, packaging innovation, value-adding, product improvement, product design innovation, alternative/new materials, quality materials, and technological innovations were used in the cluster analysis. The results show that most consumers are open to accepting innovation in handicrafts. Particularly, consumers prefer those innovations that do not modify the traditional features and characteristics of products, such as authenticity, packaging, and quality-related innovations. However, consumers considered technological innovations as more skeptical. The comparison of socio-demographic profile of consumer segments with their acceptance of innovation indicates that the younger generation and well-educated consumers are more willing to accept innovation in handicraft products. Contrarily, the old-age consumers were unwilling to accept the innovation and prefer to purchase authentic and quality products. Additionally, as income increases, people like more authentic and quality products. This study focused on an emerging topic for handicraft industry, that is, innovation considered controversial, challenging, and received less attention from scholars in past. Further, this study is the first of its kind to explore the consumer acceptance of innovation in handicraft products.

Objective Recently, China has experienced a considerable influence of the COVID-19 pandemic on the local people’s health and economy. Hence, the current research aims to investigate the psychological and socioeconomic impact of COVID-19 on rural communities in the Sichuan Province of China.Methods A total of 499 participants (village representatives of Sichuan Province) were approached to partake in a cross-sectional online survey and share their experience regarding the ongoing pandemic. The descriptive statistics and ordinary least squares (OLS) regression were used to analyse the data.Results Our analysis revealed that the pandemic has significantly affected local people psychologically, leading to socioeconomic vulnerability. Notably, we find that local households are worried about their income losses regardless of their socioeconomic status (40%–43%), level of income (37%–43%) and industry involvement (38%–43%). However, as income increases, the level of stress decreases. The results further show that government transfer payment is a significant factor in reducing stress due to its reliable and uninterrupted income flow. Contrary to our proposition, the pandemic stress was less observed, which might be because of people’s trust in government and effective antiepidemic countermeasures to contain the disease.Conclusion This study finds that COVID-19 has a significant impact on local people’s health, psychology and income. This study is one of the first to provide empirical evidence regarding the early health and socioeconomic effects of COVID-19 at the household level in rural communities, which are very important to devise policies to ease the outbreak and prevent further losses at the local community level.

This paper investigates economic impacts of COVID-19 on households based on differences in the socio-economic status (SES). We determine the household-level effects of the COVID-19 shock using income sources, types of industries, communities' resilience, household susceptibility, and relevant policy measures. For this purpose, we used primary data of 555 households collected through snowball sampling technique using an online survey questionnaire from different villages mostly located in Sichuan Province, China. Using step-wise binary logistic regression analysis, we estimated and validated the model. Results suggest the use of SES as a better measure for understanding the impacts of COVID-19 on different households. We find that households with low SES tend to depend more on farmland income and transfer payments from the government. Contrarily, high SES households focus more on business and local employment as sources of income generation. Poor households were less resilient and more likely to fall back into poverty due to COVID-19, while the opposite stands true for non-poor households with high SES. Based on the estimations, policies encouraging employment and businesses complemented with loans on lower interest rates are recommended, which may increase the SES, thus minimizing vulnerability and enhancing the households' resilience towards poverty alleviation and economic shocks.

In this talk, we investigate the collision energy and particle species dependence of kinetic freeze-out properties in relativistic heavy ion collisions from √SNN = 7.7 - 200 GeV$\sqrt {{S_{NN}}} = 7.7 - 200\,{\rm{GeV}}$SNN=7.7−200 GeV at Relativistic Heavy Ion Collider (RHIC) and 2.76 TeV at the Large Hadron Collider (LHC) with Tsallis Blast-Wave (TBW) model. Strangeness and non-strange particles show a similar radial flow, while the strange hadrons have higher temperature and smaller non-equilibrium degree. Strangeness approaches equilibrium more quickly than non-strange particles from peripheral to central collisions. The kinetic freeze-out temperature of non-strange particles in central collisions decreases from RHIC to LHC energies, while strangeness does not show this behavior. Finally we discuss the system bulk viscosity dependence on collision energy.

BackgroundThe fast breeder reactor using helium-xenon mixture gas as coolant combined with Brayton thermoelectric conversion system is the development trend of space nuclear power in the future. In order to improve the system efficiency and reduce the system mass, many scholars have carried out research on the design of reactor parameters, but few of them involved helium xenon cooled reactors.PurposeThis study aims to design key parameters of small helium xenon cooled reactor.MethodsThe single channel model, primary surface regenerator and other component models were built by using FORTRAN 95 language programming, and the thermal system program was established afterward. The basic parameters of submerged subcritical reactor were used to verify the program, and the range of key parameters was determined by sensitivity analysis of a single parameter.ResultsThe results show that the regenerator has the greatest influence on the system efficiency and mass, and the pressure ratio of the compressor over 1.52 has less influence on the system mass.ConclusionsThis study provides a reference for the design of small helium xenon cooled reactor.

The lignin-degrading enzyme system of white rot fungi is highly efficient and non-specific, and can degrade a variety of pollutants, including dyes, phenolic compounds and pesticides.The article presents an overview of the mechanism of enzymatic degradation of white rot fungi and its research status in several refractory wastewater were described.

The mass transfer rate between steel and slag determines the reaction rates of elements in a molten bath(especially the reaction rates of desulphurization and dephosphorization),and has direct impact on the distribution ratios of elements between steel and slag. In this article,Hangang 250 t converter was taken as the research object. Factors such as gas flow,lance position and bottom blowing location were taken into consideration to study the mass transfer ability of the convertor by a water model whose similarity ratio was 1:9. The results show that increasing the top-blowing intensity and the bottom-blowing intensity can greatly improve the distribution ratios of elements in the molten bath between steel and slag. The mass transfer coefficient between steel and slag decreases obviously with the drop of bottom-blowing air flow,thus a bottom-blowing air flow not lower than 0.06 m3·t-1·min-1 is suggested. The more the bottom-blowing holes are,the larger the mass transfer coefficient between steel and slag gets. A distribution plan of bottomblowing air flow is presented,which is superior to the equal distribution plan of air flow.

In this research, we have developed an approach by incorporating quantum dots (QDs) with red emission into mesoporous silica microspheres through a non-chemical process and obtained luminescent microspheres (LMS). Owing to the lattice structure of LMS, QDs were effectively protected from intrinsic aggregation in matrix and surface deterioration by encapsulant, oxygen and moisture. The LMS composite has therefore maintained large extent luminescent properties of QDs, espe-cially for the high quantum efficiency. Moreover, the fabricated white light emitting diode (WLED) utilizing LMS and YAG:Ce yellow phosphor has demonstrated excellent light performance with color coordinates around (x = 0.33, y = 0.33), correlated color temperature between 5100 and 5500 K and color rendering index of Ra = 90, R9 = 95. The luminous efficiency of the WLED has reached up to a new record of 142.5 lm/W at 20 mA. LMS provide a promising way to practically apply QDs in lightings and displays with high efficiency as well as high stability.

Abstract Carbon nanotubes were subjected to doping with an energetic Ag ion beam, and the carbon nanotubes on the top of the array were transformed into amorphous carbon nanowires with embedded Ag-nanoparticles. The field emission characteristics of these nanowires were investigated. The minimum turn-on and threshold fields were 0.68 and 1.09 V/μm, respectively, which were lower than those of the as-grown carbon nanotubes. This was probably because Ag-nanoparticles embedded in the carbon nanowires reduced the effective work function from 4.59 to 4.23 eV. Large doping amounts produced serious structural damage at the top of the nanowires and impaired the field emission characteristics.

A QR decomposition based and a minimum mean square error （MMSE） based successive interference cancel-lation receiver algorithms were proposed for the uplink of space-time block coded multi-carrier code division multiple access （MC-CDMA） systems. As the processed data matrix preserved the orthogonal structure of space-time block code, the sub-optimum decoding could be achieved via simple linear processing. Compared with the traditional zero-forcing （ZF） receiver algorithm, the proposed algorithms avoid the enhancement of white noise power at the receiver. Simulation results demonstrate the proposed algorithms outperform the ZF receiver algorithm in both independent and correlated fading channels and they require 4 dB less signal-to-noise ratio than the traditional one for a bit error rate of 10?6.