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ObjectiveTo comprehend the epidemiological and molecular characteristics of diarrheagenic Escherichia coli （DEC） in a specific district of Beijing City from 2018 to 2022， aiming to provide evidence for the prevention and control of related diseases.MethodsStool specimens of 1 600 diarrhea cases were collected from 3 surveillance sentinel hospitals in one district of Beijing from 2018 to 2022， and DEC strains were isolated from the specimens. The virulence genes were detected by multiplex PCR， and the pathogenic types were obtained. The epidemiological and clinical data were analyzed. Simultaneously， pulsed-field gel electrophoresis （PFGE） was used to ascertain the molecular types of the strains. Cluster analysis was performed on the fingerprints of ETEC， EPEC， and EAEC strains.ResultsDEC strains were isolated in 144 of 1 600 specimens from one district of Beijing from 2018 to 2022， with a detection rate of 9.00% （144/1 600）. The primary pathogenic type was ETEC， followed by EPEC， EAEC， and EHEC， no EIEC cases were detected. The male-to-female ratio of DEC infection cases was 1.48∶1， with the highest detection rate occurring in the 31~45 age group （11.15%， 59/529）. The year 2019 exhibited the highest positive detection rate of DEC， with the highest rates consistently observed during the summer months. Significant differences in the positive detection rate of DEC were observed among different age groups and years. Most of the DEC-positive patients suffered diarrhea， dehydration， abdominal pain and watery stool. The 144 DEC strains yielded 111 bands， with homology ranging from 13.07% to 100.00%. Isolates of the same type ranged from 2 to 7 strains， and their separation intervals varied from the same day to several years.ConclusionETEC and EPEC were the predominant pathogenic types of DEC in this area， while EHEC infections persisted. DEC exhibited a high incidence during the summer and was more frequently detected in young adults. The PFGE bands exhibited a highly polymorphic distribution.

Along with the development, utilization, protection, and restoration of marine resources, there are specific issues such as unclear boundaries of usage rights and disputes between sea area users and fishing rights holders. The paper starts from the realization of the right to use sea areas, proposing a shift in the spatial division of sea areas from two-dimensional to three-dimensional. The research results provide a reliable institutional guarantee for the establishment of a layered and three-dimensional mechanism for the use of sea areas, improving the development efficiency and ecological benefits of sea resources and assets, and providing comprehensive development of the marine economy.

Food image retrieval, a major task in food computing, has garnered extensive attention in recent years. However, it faces two primary challenges. First, food images exhibit fine-grained characteristics, implying that visual differences between different food categories may be subtle and often can only be observable in local regions of the image. Second, food images contain abundant semantic information, such as ingredients and cooking methods, whose extraction and utilization are crucial for enhancing the retrieval performance. To address these issues, this paper proposes an enhanced ViT hash network (EVHNet) based on a pre-trained Vision Transformer (ViT) model. Given the fine-grained nature of food images, a local feature enhancement module enabling the network to learn more representative features was designed in EVHNet based on convolutional structure. To better leverage the semantic information in food images, an aggregated semantic feature module aggregating the information based on class token features was designed in EVHNet. The proposed EVHNet model was evaluated under three popular hash image retrieval frameworks, namely greedy hash (GreedyHash), central similarity quantization (CSQ), and deep polarized network (DPN), and compared with four mainstream network models, AlexNet, ResNet50, ViT-B_32, and ViT-B_16. Experimental results on the Food-101, Vireo Food-172, and UEC Food-256 food datasets demonstrated that the EVHNet model outperformed other models in terms of comprehensive retrieval accuracy.

This study was done in order to investigate the changes of the major biochemical components and in vitro antioxidant activity of the water extracts from different kinds of tea during the process of their multistage membrane separation, ultrafiltration membranes with molecular masses cut-off (MMCO) of 20, 10, and 3.5 kDa, respectively were successively used to separate the water extracts from the major kinds of tea in Fujian including green tea, white tea, oolong tea from south Fujian, oolong tea from north Fujian, and black tea into fractions with different molecular masses. The fractions were spray dried and investigated for their ultraviolet (UV) spectra, biochemical compositions and in vitro antioxidant activity. The results showed that the UV absorption spectra of all samples were similar, exhibiting two obvious peaks at 210 and 274 nm. Absorbance at 274 nm exhibited a significant positive correlation with the contents of free amino acids (FAAs), caffeine (CAF), gallic acid (GA) and epicatechin gallate (ECG), and a significantly negative correlation with the contents of epigallocatechin (EGC) and epicatechin (EC). The distribution of biochemical components and the changes in antioxidant activity in vitro were affected by membrane separation, among which, the 20 kDa MMCO membrane had the most pronounced impact. The retentate from black tea after 20 kDa MMCO membrane ultrafiltration had the highest antioxidant activity in vitro, while the antioxidant activity of the permeate was lower than that of the permeate from the other kinds of tea. The biochemical components and antioxidant activity in vitro varied significantly among different types of tea samples, and the changes in biochemical components and antioxidant activity during the membrane separation process were not completely consistent. The water extract from black tea showed the greatest changes after 20 kDa MMCO membrane ultrafiltration. These results could provide a scientific basis for the membrane separation of aqueous extracts from different types of tea.

ObjectiveTo detect enterohemorrhagic Escherichia coli （EHEC） O157：H7， visualization recombinant enzyme polymerase amplification （RPA） detection and real-time fluorescence RPA detection methods were established based on RPA technology.MethodsPrimers and probes were designed based on the rfbE gene of EHEC O157：H7， and specificity and sensitivity were determined. A real-time fluorescent RPA method was established. Combined with the color change characteristics of SYBR Green I in nucleic acid reactions， a visualization RPA method for the detection of EHEC O157：H7 was established.ResultsThe established real-time fluorescence RPA detection and visual RPA detection methods both detected EHEC O157：H7 in 25 min at a reaction temperature of 35 ℃. The designed primers and probes showed specific results only for EHEC O157：H7. The detection limits of the two methods were lower than 10-5 ng/μL.ConclusionThe visual RPA detection and real-time fluorescence RPA detection methods of EHEC O157：H7 were easy to operate with strong specificity and high sensitivity. This study provides novel methods for the rapid detection of EHEC O157：H7 in the field and laboratory.

【Objective】 Yongji, located in the Hetao Irrigation district, has implemented a strategy of alternating between groundwater and surface water for irrigation to conserve water resources. This paper presents the outcomes of an experimental investigation into the repercussions of this practice on groundwater table change. 【Method】 The experiment was carried out in the Jingqu area of the Yongji irrigation district from 2018 to 2019. It involved measurement of the changes in groundwater depth, total salt content, total nitrogen, and phosphorus levels at 13 boreholes distributed across the region. We analyzed their spatial distribution and overall impact on groundwater dynamics. 【Result】 The alternating use of surface and groundwater for irrigation led to a reduction in the average groundwater depth by 0.15 meters. Simultaneously, it increased the average variation by 0.26 meters, and the coefficient of variation for groundwater depth by 1.13%, with the upper reaches of the irrigation district most affected. The decrease in irrigation area resulted in a reduction in areas with high salt content in groundwater, notably in the southeast of the upper reaches and northwest of the lower reaches, where the total salt content was reduced from 500 to 5 000 mg/L and 500 to 3 500 mg/L, respectively. Alternate irrigation also reduced the area with total nitrogen concentration exceeding 2 mg/L by an average of 14.38%, in addition to a marginal reduction in nitrogen and phosphorus in groundwater. The total nitrogen content in groundwater varied between 1 and 2 mg/L, while the area with total phosphorus content below 0.09 mg/L and 0.13 mg/L increased by 29.04% and 15.58%, respectively. 【Conclusion】 Alternate groundwater and surface water for irrigation can improve the utilization efficiency of groundwater and groundwater circulation. It also improved groundwater quality and alleviated the shortage of water resources in this region.

Background In the initial promotion of pilot hospice care services (HCS) in China, there is an urgent need to evaluate the quality and effectiveness of HCS comprehensively in pilot institutions. Objective The purpose of this study was to establish a meso-level comprehensive assessment system of hospice care, and to provide a scientific measurement tool for assessing and comparing hospice care in various pilot institutions. Methods An item pool for establishing a comprehensive assessment system for HCS was constructed through a literature review and small-scale expert interviews from April to May 2021, then the items were rated using a 9-1 grading scheme (the highest grade is 9, while 1 is the lowest) in terms of three aspects (relevance, measurability and feasibility) during two rounds of expert consultation conducted using the RAND/UCLA modified Delphi panel method from June to July 2021. Results The Comprehensive Assessment System of Hospice Care (CASHC) was established finally after the items were revised and improved according to the results of two rounds of expert consultation, which consists of 3 primary indicators (structure, process and outcome), 9 secondary indicators (policy guarantee, service provision, patient burden, etc.), 25 tertiary indicators (institutional system guarantee, number of services, per capita cost, etc.) and 81 quaternary indicators (inclusion of institutional development plan, number of hospital discharges and per capita medical cost, etc.). The first round of consultation achieved a response rate of 93.3%, an authority coefficient of 0.900, with values of Kendall's W for the quaternary indicators calculated as 0.194, 0.115, and 0.126, respectively. The second round of consultation achieved a response rate of 92.9% and an authority coefficient of 0.900, with values of Kendall's W for the quaternary indicators of 0.417, 0.241, and 0.322, respectively. Conclusion The CASHC consisting of four-level indicators established using the Donabedian's structure-process-outcome framework is an innovative and practical tool, which can be used to quantify and compare the quality and effectiveness of HCS among different pilot institutions or different regions, contributing to the promotion of the standardization and homogenization of HCS in pilot regions.

Aiming at the intersection processing of underground mine scene roadway in 3D virtual environment, a modeling and rendering system of mine roadway 3D virtual environment based on WebGL is constructed. The binary spatial bifurcation tree (BSP) is used for roadway intersection modeling, which realizes the construction and rendering of three-dimensional solid geometry of underground roadway, and effectively reduces the modeling complexity. Based on WebWorker multi-thread real-time modeling and loading method of large-scale scene model, a strategy for separating scenario management from modeling is carried out, which can not only build the roadway model dynamically according to the parameters, but also avoid the blocking problems such as user jams and unfriendly interface operation due to the long modeling and loading time of large scene models over 1 G, such as the number of vertices and texture, so as to improve the effect and performance of scene interaction and real-time roaming.

To meet the requirement of numerical weather prediction for local severe convective weather, especially disastrous weather and extreme weather events, based on GRAPES-MESO 10 km system, many works have been completed, which include improving the calculation accuracy and stability of the model dynamic framework, selecting and testing the physical parameterization schemes suitable for high-resolution model, establishing a national radar quality control preprocess system, applying the national (SA/SB/CB) three-dimensional network mosaic data through the cloud analysis system, establishing a convective resolvable assimilation system and land surface data assimilation system for small and medium-scale systems, implementing the assimilation and application of unconventional local dense data such as radar radial wind, wind profile radar, FY-4A imager emissivity, satellite cloud motion wind, satellite GNSSRO, surface precipitation and the near surface data, and developing the rapid cycle technology. By integrating all the jobs mentioned above, the nationwide rapid analysis and forecast system CMA-MESO (GRAPES-MESO 3 km)has been established and put into operational run since June 2020 with 3 km horizontal resolution and 3 h time interval. The operational verification results in flood season from June to September of 2020 show that the forecasts of near surface elements (precipitation, 2 m temperature and 10 m wind) of CMA-MESO forecast surpass the results of GRAPES-MESO 10 km system, and the threat score for 3 h accumulated precipitation forecast is outstanding. The threat score for 24 h accumulated precipitation of CMA-MESO is slightly worse than the result of ECMWF, but the threat score for 3 h accumulated precipitation forecast is significantly better. For the precipitation exceeding 10.0 mm, CMA-MESO performs better than ECMWF within all the lead times, and the advantages are more obvious with the increase of precipitation threshold. Compared to ECMWF, CMA-MESO shows more obvious advantages on daytime forecast. For 25 mm precipitation threshold, the improvement rate exceeds 50% in most of the daytime and reaches about 100% in the later stage of forecast. The spatial distribution of mean 24 h accumulated precipitation predicted by CMA-MESO and ECMWF models is close to the observation, but the amount predicted by CMA-MESO is slightly larger. The frequency and intensity of precipitation simulated by CMA-MESO, which can characterize the ability of model to predict the spatial-temporal fine characteristics of precipitation, are consistent with observation in terms of both horizontal distribution and magnitude. The comprehensive performance of CMA-MESO in flood season in China exceeds that of ECMWF fine grid model.

BackgroundLeft ventricular ejection fraction (LVEF) is often used to classify heart failure (HF) . Some HF patients were observed to have improved ejection fraction after treatment, thus giving rise to the concept of HF with improved EF (HFimpEF) . However, most relevant studies have focused on European countries and the US, and there are few reports on the clinical characteristics and diagnosis of this population in China.ObjectiveTo analyze the clinical characteristics, prognosis and prognostic predictors in Chinese HFimpEF patients.MethodsParticipants included in this case-control study were chronic HF inpatients who were recruited from Department of Heart Center, Hebei General Hospital from June 1, 2018, to May 1, 2020. Demographic data and baseline clinical information were obtained from the electronic medical record, in particular, clinical phenotypes of HF classified by baseline and follow-up LVEF included four: HF with preserved EF (HFpEF) , HF with mid-range EF (HFmrEF) , HF with reduced EF (HFrEF) and HFimpEF. Follow-up was conducted via electronic medical record review, outpatient department and telephone since the last reexamination with echocardiography. The follow-up continued through 2021-06-01, with all-cause death and all-cause readmission as endpoint events. Predictors of HFimpEF were explored by binary Logistic regression. Kaplan-Meier estimator was used to describe the survival of patients with all-cause death and all-cause readmission. Cox regression model was used to identify risk factors for all-cause death and all-cause readmission.ResultsA total of 530 cases were included, including 245 (46.2%) with HFpEF, 55 (10.4%) with HFmrEF, 133 (25.1%) with HFrEF, and 97 (18.3%) with HFimpEF. HFimpEF patients had lower mortality than did HFpEF patients (P=0.014) and HFmrEF patients (P

In the background of the Chinese modernization, what is the proper way for the foreign language discipline in China to develop? How can improvement and effectiveness, orthodoxy and innovation be realized in the teachings of foreign languages? Ten well-known deans of schools of foreign studies in China have been cordially invited by Language Education to hold a mutual discussion in relation to discipline construction, training of undergraduate and graduate (both master and doctor) talents, curriculum setting and reform, construction of the intelligent platform for the discipline, transformation of disciplinary paradigm by digital and intelligent integration, the localization of the model of international development, etc. [ABSTRACT FROM AUTHOR]

A case of bullous pilomatricoma is reported. A 22-year-old female had brown blue nodule on the right shoulder for 3 months and blisters for over 2 months. Dermatological examina-tion revealed a demarcated 1.6 cm X 1.0 cm x 0.7 cm light purple semi translucent bulla with loose wall and movable base on the right shoulder. A movable hard mass sized 0.4 cm x 0.3 cm could be palpated. Histopathological examination of the lesion showed a mass with clear boundaries, and filtrates of basophils, transitional cells and shadow cells, along with proliferation and dilation of lymphatic vessels. The diagnosis was bullous pilomatricoma. Following surgical removal of the tumor, no recurrence was observed during 6 months of follow-up. [ABSTRACT FROM AUTHOR]

This article summarizes the current research status of manganese-based materials as cathode materials for sodium-ion batteries, focusing on the effects of their structural characteristics, doping modification, and optimization strategies on electrochemical performance. Manganese-based materials have attracted much attention due to their low cost and abundant resources, but their cycle stability and rate performance still need to be improved. Research has revealed that by fine-tuning the material structure, introducing doping elements, and optimizing the preparation process, the conductivity, structural stability, and sodium ion diffusion kinetics of the material can be significantly enhanced, thereby improving the battery performance. This article also summarizes the advantages and disadvantages of current preparation methods, and looks forward to future research directions, aiming to provide theoretical guidance and reference for promoting the performance optimization and practical application of manganese-based cathode materials for sodium-ion batteries. [ABSTRACT FROM AUTHOR]

In order to enhance the UV absorption characteristic of epicatechin derivatives and improve their solubility in non-polar solvents such as oils and fats, 2,2'-di(p-hydroxybenzocarbonyl)-epicatechin was synthesized from epicatechin and p-hydroxybenzoic acid using methane sulfonic acid as solvent and catalyst. The target products were separated by column chromatography, and the purity was verified by high performance liquid chromatography (HPLC), and the structure of the target products were verified by UV-vis, FT-IR, ¹H NMR, 13C NMR, LC-MS spectroscopy. The UV absorption characteristic of 2,2'-di(p-hydroxybenzocarbonyl)-epicatechin and its ability to scavenge ABTS+·, DPPH· and O2-· were evaluated. The results show that the synthesized 2,2'-di(p-hydroxybenzocarbonyl)-epicatechin had similar UV absorption and comparable molar absorptivity to OMC, the commonly used UV absorber, and is expected to be an excellent UV absorber in the UVB band. 2,2'-di(p-hydroxybenzocarbonyl)-epicatechin had good antioxidant activity in vitro, and its antioxidant capacity in vitro was higher than that of VC and slightly lower than that of epicatechin, which is expected to be used for cosmetic applications. [ABSTRACT FROM AUTHOR]

In English translations of classical Chinese poems, the principle of "beauty in sound" proposed by Xu Yuanchong is a key criterion to examine the prosodic loyalty. This paper compares prosodic differences between the Chinese poem, "Kwan Ts'eu", and its three English translations (Xu Yuanchong, James Legge and Ezra Pound) in terms of rhythm, sound, and rhyme with Praat. The quantitative results show that in terms of rhythm, all three translations effectively replicate the musical feature of the poem through syllables, vocabulary and tones. Regarding sound, ratio of vowels and consonants and suprasegmental features (pitch, intensity, and length) in Xu Yuanchong's and Legge's translations exhibit a higher degree of correspondence with the original poem. Moreover, all three translations take advantage of a large amount of alliteration, assonance, and consonance to reproduce the prosodic beauty of reduplication and alliteration in the original poem. The comparative study explores the construction of "beauty in sound" in English translation of Chinese poetry with a quantitative method, which sheds light on the extension of approaches to analyzing poems. [ABSTRACT FROM AUTHOR]

A SiC-enhanced carbon nanofiber composite (SiC@CNFs) structure was prepared by electrospinning technology combined with carbonization process. The results of TGA, XRD, XPS and SEM show that the mass fraction of SiC particles is 62%, and it is evenly distributed on the surface of CNFs. The lithium-ion battery anode material prepared by this structure not only retains the high electrical conductivity of CNFs, but also obtains the enhanced structural toughness of SiC. The electrochemical performance test results show that the capacity retention rate of the lithium-ion battery anode material is as high as 134.01% after 500 cycles, much higher than that of CNFs. Moreover, the electrochemical impedance value of the structure changes less and the conductivity of SiC@CNFs remains good. SiC@CNFs structures prepared by electrospinning technology serve as lithium-ion battery anode, with low production cost, controllable structure and stable performance, which is a beneficial supplement to the current battery cathode materials. [ABSTRACT FROM AUTHOR]

[Purpose/Significance] Chinese ancient books are one of the most important carriers to condense the essence of Chinese traditional culture. However, scholars have found that the database of Chinese ancient books only provides book metadata, which can only meet the basic retrieval and use needs of users, but does not dig and utilize Chinese ancient books in depth from the perspective of knowledge organization. The research in digital humanities is in the ascendant, providing an important modern scientific and technological means for the realization of knowledge correlation of Chinese ancient books. The research on the content mining and knowledge correlation of Chinese ancient books will help to improve the development level and service quality of Chinese ancient books, and promote the creative transformation and innovative development of Chinese excellent traditional culture. [Method/Process] Through literature review and online investigation, this paper summarizes the research of Chinese ancient books' knowledge correlation from the perspective of digital humanities. Based on the research, this paper discusses the differences between traditional database and digital humanistic platforms of Chinese ancient books. First, the organization mechanism is different, and the latter has more diverse and in-depth functions. Second, the scope of collection is expanded. The latter includes not only the original documents, but also the analytical texts and extended documents of ancient books, etc. In the past, most database platforms were "digital" platforms; The digital humanistic platform of Chinese ancient books is a platform of "data", which has been upgraded from "storage" to "analysis" and "correlation". Then, the key links of Chinese ancient books' knowledge correlation are discussed, and the barriers of knowledge correlation are analyzed by examples. [Results/Conclusions] From the perspective of digital humanities, collation of Chinese ancient books has developed from document units to knowledge units by using the data analysis technology, machine learning, visualization technology, etc. The realization of knowledge correlation of Chinese ancient books starts from document organization, based on ancient book data, and its essence is knowledge organization. Knowledge correlation of Chinese ancient books can be used for local chronicles and genealogy mining, seal knowledge network discovery, research context and communication analysis of scholars in specific periods and regions. However, the current knowledge correlation of ancient books still faces barriers such as the difficulty of knowledge element processing, high technical requirements and the lack of integrated platforms in its implementation. Limited by the research conditions, this paper only discusses the research and application, key links and barriers of ancient books' knowledge correlation from a theoretical point of view. In the future work, we will take the opportunity of optimizing and upgrading our ancient books' knowledge platform, to further study the metadata description specification, text conversion and content mining of Chinese ancient books, data exchange and update mechanism among different platforms. [ABSTRACT FROM AUTHOR]

Particles will be mixed in journal bearings during operation. In order to investigate the effect of particles on oil film characteristics of journal bearing, based on the theory of fluid lubrication, a mathematical model of the dynamic and static characteristics of hydrodynamic journal bearings considering particles was established. The governing equation was discretized by the finite volume method and the first-order upwind,the discretized equation was solved by SIMPLE algorithm, and the influence of particle content on the bearing capacity and friction of the oil film was analyzed. The dynamic mesh-spring smoothing technology was used to update the volume mesh after the journal moves to solve the dynamic characteristic coefficient of the bearing, and the influence of impurity particles on the dynamic characteristic coefficient was analyzed. Results show that the bearing capacity and friction of the oil film ascend at first and then become stable with the increase of particle content, indicating that the particles can improve the oil film bearing capacity to a certain extent, but also increase the friction. The temperature of the oil film is symmetrically distributed around the oil inlet, and the oil film temperature decreases first and then increases in the axial direction. After considering the effect of particles, the four stiffness coefficients of the oil film all decrease, while the oil film damping coefficients Cxx and Cxy decrease, and Cyx and Cyy increase. [ABSTRACT FROM AUTHOR]

Based on the principle of geometric phase, the relevant research of generating vortex beam by metasurfaces (the plasmonic metasurfaces, the all-dielectric metasurfaces, the Gap-plasmon metasurfaces and the multi-function metasurfaces) was reviewed in recent years. It was pointed out that the metasurfaces based on the geometric phase had the characteristics of simple design and dispersion-free of vortex beam. In the near-infrared band, the plasmonic metasurfaces had the characteristics of easy fabrication and broadband, the all-dielectric metasurfaces had the characteristic of high transmittance. In the mid-infrared band, the Gap plasmon metasurfaces had the characteristics of high reflectance and aberration-free. The multi-function metasurfaces were capable of generating vector and scalar vortex beams simultaneously. With the maturity of nanofabrication technology, in the future, metasurfaces will develop in the direction of low loss, broadband, adjustability, multifunction and so on, and the advanced nano-fabrication technology will enable metasurfaces available for integrated optical system. [ABSTRACT FROM AUTHOR]

To better understand the aroma characteristics of oolong tea, the volatile compounds of three representative Fujian oolong tea samples (Tieguanyin, Rougui and Shuixian) were isolated by simultaneous distillation-extraction (SDE) and head space solids-phase microextraction (HS-SPME) coupled with three different fiber coatings, and analyzed by gas chromatography-mass spectrometry (GC-MS). 262 aroma components were detected by different extraction methods. The number of aroma components detected from high to low was 204 (Rougui), 175 (Shuixian), and 120 (Tieguanyin), respectively. HS-SPME with dry samples were detected with 186 aroma components, followed by HS-SPME with wet samples (139), and SDE method detected 33 aroma components. Different extraction methods can complement each other on the detection of aroma components. A 65 µm PDMS/DVB (Polydimethylsiloxane/Divinylbenzene) fiber showed good reproducibility, and some common or characteristic aroma components in oolong tea samples were robustly detected, such as nerolidol, indole, alpha-farnesene, phenylethyl alcohol, benzyl nitrile, methyl salicylate, etc. Compared with Tieguanyin, Rougui and Shuixian had higher number of aroma components, and the aroma compositions of Rougui were the most complex. These results were in consistent with the sensory evaluation of oolong tea produced from north and south of Fujian province, and Rougui showed higher aroma quality than that of Shuixian. [ABSTRACT FROM AUTHOR]

Using AC-13 modified asphalt mixture as the research object, the whole weathering accelerator was used for 0~3000 hrs aging test at different UV intensities. The aging asphalt mixtures were subjected to high-temperature rutting, low-temperature trabecular bending, freeze-thaw splitting and fatigue tests, respectively, comparing and analyzing the changes of pavement performance for asphalt mixtures. The results showed that when the conditions of thermal oxygen aging and humidity were same, the high-temperature stability of asphalt mixture increased first and then decreased after increasing the intensity of UV. With the increase of the stiffness modulus of the asphalt mixture, the crack resistance at low temperature decreased slightly. On the contrary, the water stability and fatigue performance of the asphalt mixture decreased greatly. [ABSTRACT FROM AUTHOR]

Due to the lack of quantitative models for managing air traffic flow and the congestion of air routes and intersections, the route impedance function was defined according to the characteristics of air traffic flow and the queuing theory. An optimal traffic capacity model considering the distribution of altitude levels was developed based on the improved optimal system model. Meanwhile, a solution algorithm for phased distribution flow was designed. The simulation results showed that the model can quickly coordinate the traffic of each intersection in the route network when there was congestion at an intersection. By comparing the impedance function of each route, the model can distribute the traffic and disperse the congestion. [ABSTRACT FROM AUTHOR]

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For minimizing the total delay time, a route selection model is set up to choose a reasonable route from fixed or temporary routes for each flight reaching the intersection. And the corresponding heuristic algorithm is introduced to calculate the global optimal solution of the model. Finally three scenarios are designed to simulate the flight data of airline between Jiayuguan and Yabulai on the map. The simulation results show that the model and the algorithm can solve the optimal multiple-flight route options, and cost the minimum total delay time, thus indicating the effectiveness of the method. [ABSTRACT FROM AUTHOR]

Cotton, one of the most important economic crops in our country, always suffers a variety of pest during the whole process of planting. Blind stinkbug, which seriously affected the cotton quality and yield during BT cotton, is planted in large areas of the Yellow River and Xinjiang province in China. Traditional cotton blind stinkbug hazard ration identification method relies too much on experience, but recognition accuracy and recognition speed are low. In view of complex background of cotton blind stinkbug hazard region and the difficulty in segmentation and classification under natural conditions, an automatic classification method of Cotton blind stinkbug hazard level was proposed. On the basis of the classification standard of plant diseases and insect pests and hazard characteristics of cotton blind stinkbug, as well as the harm degree distribution of bug to cotton by artificial statistics, the cotton blind stinkbug damage grade was divided and the damage grade standard of bug to cotton was put forward. The processing steps of the cotton leaf image in different bug damage grade acquainted in natural conditions were as follows. Firstly, by using Q color component and Otsu segmentation method, the image background was divided. Secondly, in order to remove burrs after splitting, morphological opening operation and internal filling algorithm were used to deal with the segmented image, and the largest connected component was extracted, which can eliminate the influence of weeds. Thirdly, the disease regions of cotton were extract by H+a*+b* component and Otsu segmentation method based on blind stinkbug hazard cotton leaves. The adhesion cotton leaves were separated by Watershed segmentation method Forth, and extracted and selected contents including the color, texture and shape features of and cotton leaf hazard by blind stinkbug. In accordance with the principle of distinction and difference, color feature, texture feature and shape feature was the input indicators classifier. Based on the statistical results of color, texture and shape feature of bug damage image to cotton, R component, G component, B component, I1 component, S component and V component were selected as the color feature, Contrast and Correlation were selected as the texture feature, Pa value were selected as the shape feature. Finally, based on Matlab R2008 platform, combined with the bug feature variables and naive Bias classifier extraction, this method had the aim to distinguish the cotton blind stinkbug damage grade based on the cotton bug division of the harm grade standard. In this experiment, 120 cotton blind stinkbug damage leaves image with 6 levels were used for simulation, in which 60 images were the training set and the others were the validation set. Different bug harm level recognition experiment results showed that, the model has advantages in accuracy and speed with average rate of correct recognition as 90% and average operation time as 0.278 seconds, which was better than Support vector machine and BP neural network model. The proposed cotton blind stink bug hazard grade standard can provide a theoretical basis for the study of harmful cotton blind stinkbug. The proposed classification method of cotton blind stinkbug hazard rating will not only promote technical level for the prevention and treatment of the cotton blind stinkbug, but also it provides a reference for the identification and control of other pests. [ABSTRACT FROM AUTHOR]

Objective To explore the ability of the biological composite materials. HA-glass coating/porous Zr02, inducing SD rat bone marrow mesenchymal stem cells to differentiate into osteoblasts in vitro, to find the ideal composite carrier of transplantated bone marrow mesenchymal stem cells and to investigate the security after transplantation, and to lay foundation for the fast recovery treatment of bone defect. Methods SD rat bone marrow mesenchymal stem cells were induced to differentiate by biological materials in vitro. Then cells were cultured for 14 days and 21 days. After dying with calcium-cobalt according to Gomori, Von Kossa staining, and immunohislochemical technology, the expression of alkaline phosphatase, calcium nodules, and type 1 collagen was detected. The changes of the expression of CD45, CD44, and CD90 in the cells before and after the induction were detected using flow cytometry. Results After 14-day induction in vitro, the cell morphology of SD rat bone marrow mesenchymal stem cells changed from long shuttle deformation cells to triangle or polygon cells, and there were clear boundaries between the cells. The expression of alkaline phosphatase was positive. After 21-day induction, dense and circular mineralized nodules appeared in cells, and the expression of type I collagen was positive. The boundaries between cells were blurred. According to the results of flow cytometry technology, the expression of CD44 was still positive, and the expression of CD45 was still negative. But the expression of CD90 transformed from positive to negative. The positive expression rate of cells decreased from 99.1% to 0- 29%. Conclusion Biological composite materials, HA-glass coating/porous ZiQ2 scaffolds, successfully induce SD rat bone marrow mesenchymal stem cells to osteoblasts. These materials can combine with bone formation through strong chemical bond, which can be used as bone defect tilling materials, and provide support for the formation of new bone, and play the conduction role in bone. [ABSTRACT FROM AUTHOR]

Objective: To evaluation the influences of lateral occlusal forces to stress distribution in filling material after the restorative therapy of wedge-shaped defect. Methods: A three-dimensional finite element model of maxillary first premolar with wedge-shaped defect was established. The defect zone of the model with simulated glass ionomer was restored. Loads of different directions were applied on the model and stress analysis of restorative material were conducted. Results: When the loading direction was parallel to the tooth long axis, restorative material unit subjected to relative small stress. When the loading direction was vertical to the cusp inclined plane, stress endured by restorative material unit was significantly increased, as the angle of loading inclination increased, the increase of stress became more pronounced. Conclusion: After the restorative treatment of wedge-shaped defects in clinical, occlusal adjustment should be applied to reduce the inclination of cusp to relieve the lateral forces subjected by tooth so as to ease the stress burden of restorative material. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of imatinib on the growth of A549 non-small cell lung cancer transplanted tumors and the expression of PDGFB and PDGFRβ proteins in tumor tissues and stroma in nude mice and to explore the underlying tumor suppression mechanism. Methods A transplantation tumor model of A549 non-small cell lung cancer was established in nude mice. The mice were then randomly divided into four groups: control group (0.9%NaCl), low-dose imatinib group (50 mg/(kg·d)), medium-dose imatinib group (100 mg/(kg·d)), and high-dose imatinib group (200 mg/(kg·d)). The effect of different concentrations of imatinib administered by continuous gavage on tumor growth was observed for 28 days. HE staining was performed to observe the pathological changes of tumor tissues. The expression of PDGF/PDGFR pathway-related proteins and the phosphorylation levels of AKT and ERK1/2 proteins in tumor tissues were detected by Western blot analysis. Double immunofluorescence staining was used to detect the expression of PDGFB and PDGFRβ proteins in the tumor stroma. Results Imatinib inhibited the growth of A549 non-small cell lung cancer cells in nude mice, suppressed the expression of PDGFB in tumor tissues, and decreased the phosphorylation levels of PDGFRβ, AKT, and ERK1/2. The expression of PDGFB and PDGFRβ in tumor stromal fibroblasts of the administered group was significantly lower than that of the control group. Conclusion Imatinib exhibits a pronounced inhibitory effect on A549 xenografts of nude mice with non-small cell lung cancer, and its antitumor mechanism may involve the downregulation of PDGFB and PDGFRβ expression in tumor stromal fibroblasts.

ObjectiveTo provide basis for further ensuring the safety of student meals， the microbial contamination status in kindergarten， primary and secondary school canteens in Wenzhou in the past five years were investigated.MethodsFood samples collected in Wenzhou from 2016 to 2020 were detected for hygienic target bacteria （Aerobic Plate count and Escherichia coli） and foodborne pathogens （Staphylococcus aureus， Bacillus cereus， Salmonella and Listeria monocytogenes）， and data were analyzed with SPSS 18.0.ResultsThe microbial contamination of student meal in 2016 was serious， with a unqualified rate as high as 23.58%. While the unqualified rates of student meal decreased by 6.27%， 6.80%， 9.06%， and 3.82% from 2017 to 2020 （χ2 = 60.852， P

ObjectiveTo compare the efficacy between the Mycob.T scanner system and manual microscopy for detecting acid-fast bacilli in sputum specimens.MethodsBetween January and November 2020， a total of 1 519 sputum samples from suspected primary tuberculosis patients from 5 designated tuberculosis hospitals in Shanghai were examined by Smear and BACTEC MGIT 960 liquid culture （liquid culture） methods. Each specimen was subiected to 2 direct smear slides. One slide was stained by Z-N method and examined with manual microscopic method. Another slide was stained and scanned by the Mycob.T system. The efficacy of manual microscopy and the Mycob.T scanner system for detecting acid-fast bacilli in sputum specimens was compared based on the result of liquid culture. Results of the repetitive scanning by the Mycob.T scanner system and the recheck of the manual microscopy were analyzed.ResultsThe average positive rate by the Mycob.T scanner system was 14.4% （219/1 519） while the average positive rate by manual microscopy was 16.3% （248/1 519）. No significant difference was observed （χ2=2.13， P=0.145）. Based on liquid culture confirmation results， the sensitivity of manual microscopy （60.36%） was higher than that of the Mycob.T scanner system （52.94%）， and the difference is statistically significant （χ2=4.38， P=0.036）. Both methods had high specificity （98.94%）. The concordance of the Mycob.T scanner system and manual microscopy was 95.46%， with the kappa value of 0.826. The results of repeatability test of the Mycob.T scanner system and the recheck results of the manual microscopy showed that the coincidence rate of scanning by the Mycob.T scanner system was 99.5% （436/438）， and the recheck coincidence rate by the manual microscopy was 98.6% （432/438）.ConclusionThe Mycob.T scanner system have high specificity for detecting acid-fast bacilli in sputum samples and good consistency with the results of manual microscopy. Compared with manual microscopic examination， the Mycob.T scanner system can greatly alleviate the work intensity.

ObjectiveTo explore the relationship among the perception of interparental conflict， meaning in life and suicidal ideation in patients with borderline personality disorder.MethodsA total of 90 borderline personality disorder patients who visited the Psychiatry or Psychological Counseling Department of the Fourth People’s Hospital of Linyi from June 2017 to December 2020 were enrolled as study group. All patients met diagnostic criteria of Diagnostic and Statistical Manual of Mental Disorders， fifth edition， （DSM-5）. Meantime， another 90 freshmen， sophomores and juniors from a university were set as control group. All selected individuals were assessed using Children's Perception of Interparental Conflict Scale （CPIC） and Meaning in Life Questionnaire Chinese Version （MLQ-C）， then Self-rating Idea of Suicide Scale （SIOSS） was utilized in study group to evaluate the suicidal ideation.ResultsCompared with control group， study group had significantly higher total score and each dimension score of CPIC （t=-2.863~4.728， P

The progressive damage analysis technique was studied by using finite element method and test validation of the repaired aircraft wing composite panel with discrete-source damage. Firstly,an analysis model adopting the two dimensional LaRC05 and B-K failure criteria was established to indentify the initial damage of composite ply and interface. Then,a user defined subroutine UMAT of material failure criteria and degradation rule based on commercial software ABAQUS was programmed and the load carrying capacity of the repaired aircraft wing composite panel was analyzed. The numerical results indicated that: the FEM analysis method presented in this paper was viable for the large-scale bolted repair structure. The comparison between analysis and test indicates that the load carrying capacity and failure mode of numerical results agree well with test results. The errors of predicted load carrying capacity are within 5%.

Since the wing is the principle bearing structure of aircraft,wing skin is repaired by using mechanically fastened joints. In this paper,scheme design,experimental verification,finite element analysis and design improvement investigation of aircraft composite wing panel with discrete-source damage were carried out. Firstly,the specimen with discrete-source damage and the repaired which used fastened joint repair method were designed and manufactured. Experimental verification of scheme design was performed. Load-carrying capacity of the repaired specimen increases about 124%,compared to the unrepaired,which fully meet the design requirements. Then,for further analysis,two different specimens’ FEM models were established.The results showed that the initial repaired scheme was conservative,and the cost of structure weight was increased. Finally,three improved design configurations were proposed,and the load-carrying capacity of configuration II increased by 4. 7%,its structure weight decreased by 3. 9%. This repaired scheme provides reference for the repair design of aircraft composite wing panel with discrete-source damage.