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| 1 | Global patterns of breast cancer incidence and mortality:A population-based cancer registry data analysis from 2000 to 2020显示文摘Background:Breast cancer is the most commonly diagnosed cancer and leading cause of cancer death among women worldwide but has patterns and trends which vary in different countries.This study aimed to evaluate the global patterns of breast cancer incidence and mortality and analyze its temporal trends for breast cancer prevention and control.Methods:Breast cancer incidence and mortality data in 2020 were obtained from the GLOBOCAN online database.Continued data from the Cancer Incidence in Five Continents Time Trends,the International Agency for Research on cancer mortality and China National Central Cancer Registry were used to analyze the time trends from 2000 to 2015 through Joinpoint regression,and annual average percent changes of breast cancer incidence and mortality were calculated.Association between Human Development Index and breast cancer incidence and mortality were estimated by linear regression.Results:There were approximately 2.3 million new breast cancer cases and 685,000 breast cancer deaths worldwide in 2020.Its incidence and mortality varied among countries,with the age-standardized incidence ranging from the highest of 112.3 per 100,000 population in Belgium to the lowest of 35.8 per 100,000 population in Iran,and the age-standardized mortality from the highest of 41.0 per 100,000 population in Fiji to the lowest of 6.4 per 100,000 population in South Korea.The peak age of breast cancer in some Asian and African countries were over 10 years earlier than in European or American countries.As for the trends of breast cancer,the age-standardized incidence rates significantly increased in China and South Korea but decreased in the United States of America(USA)during 2000-2012.Meanwhile,the age-standardized mortality rates significantly increased in China and South Korea but decreased in the United Kingdom,the USA,and Australia during 2000 and 2015.Conclusions:The global burden of breast cancer is rising fast and varies greatly among countries.The incidence and mortality rates of breast cancer increased rapidly in China and South Korea but decreased in the USA.Increased health awareness,effective prevention strategies,and improved access to medical treatment are extremely important to curb the snowballing breast cancer burden,especially in the most affected countries. | Shaoyuan Lei Rongshou Zheng Siwei Zhang Shaoming Wang Ru Chen Kexin Sun Hongmei Zeng Jiachen Zhou Wenqiang Wei | 2021 | Cancer Communications2021，41，11： | 55 |
| 2 | Characteristics and applications of gas desorption with excavation disturbances in coal mining显示文摘 | Jiachen Wang | 2015 | International Journal of Coal Science & Technology2015，2，1： | 31 |
| 3 | Initial identification of heavy metals contamination in Taihu Lake, a eutrophic lake in China显示文摘A detailed investigation of seven heavy metals (Cu, Cd, Cr, As, Pb, Zn, Ni) in the water column, interstitial water and surface sediment was conducted to quantify the extent of their contamination in Taihu Lake. Results showed the average total concentrations ranged from 0.93 μg/L for Cd to 47.03 μg/L for Zn. The dissolved concentrations in the overlying water ranged from 0.06 μg/L for Cd to 15.86 μg/L for Zn. The metals in the Taihu Lake surface water were primarily in the particulate phase, especially for Cd, whose particulate concentration represented 94.3% of the total. In the surface sediment, the mean concentrations for Cr, Ni, Cu, Zn, As, Cd and Pb were 41.50, 28.72, 27.82, 65.46, 5.94, 0.82 and 41.17 mg/kg, respectively. The metals in the water column and sediments of Taihu Lake displayed significant spatial variations, and the higher metal concentrations mainly occurred in the north and west of Taihu Lake, especially in Zhushan Bay and West Taihu Lake. A quality assessment indicated that most of the metals in the surface water of Taihu Lake had no or low adverse health effects on organisms, except for Pb and Cu, which may cause chronic toxicity. Compared with the 'Consensus-Based Sediment Quality Guidelines', the polluting metals were Cr, Ni and Cd, and the polluted regions were confined to Zhushan Bay, Meiliang Bay and the west of Taihu Lake, especially for north of Zhushan Bay. The polluted areas for Cr, Ni and Cd were 14.36, 34.70 and 13.24 km 2 , respectively. We suggest that Cr, Ni, and Cd in the polluted areas should be addressed and that tissue chemistry and sediment toxicity assessments be performed as soon as possible. | Xia Jiang Wenwen Wang Shuhang Wang Bo Zhang Jiachen Hu | 2012 | Journal of Environmental Sciences2012，24，9： | 26 |
| 4 | Enhancement of human ACAT1 gene expression to promote the macrophage-derived foam cell formation by dexamethasone显示文摘In macrophages, the accumulation of cholesteryl esters synthesized by the activated acyl-coenzyme A:cholesterol acyltransferase-1 (ACAT1) results in the foam cell formation, a hallmark of early atherosclerotic lesions. In this study,with the treatment of a glucocorticoid hormone dexamethasone (Dex), lipid staining results clearly showed the large accumulation of lipid droplets containing cholesteryl esters in THP- 1-derived macrophages exposed to lower concentration of the oxidized low-density lipoprotein (ox-LDL). More notably, when treated together with specific anti-ACAT inhibitors, the abundant cholesteryl ester accumulation was markedly diminished in THP-l-derived macrophages, confirming that ACAT is the key enzyme responsible for intracellular cholesteryl ester synthesis. RT-PCR and Western blot results indicated that Dex caused up-regulation of human ACAT1 expression at both the mRNA and protein levels in THP-1 and THP- 1-derived macrophages. The luciferase activity assay demonstrated that Dex could enhance the activity of human ACAT1 gene P1 promoter, a major factor leading to the ACAT1 activation, in a cell-specific manner.Further experimental evidences showed that a glucocorticoid response element (GRE) located within human ACAT1gene P1 promoter to response to the elevation of human ACAT1 gene expression by Dex could be functionally bound with glucocorticoid receptor (GR) proteins. These data supported the hypothesis that the clinical treatment with Dex,which increased the incidence of atherosclerosis, may in part due to enhancing the ACAT1 expression to promote the accumulation of cholesteryl esters during the macrophage-derived foam cell formation, an early stage of atherosclerosis. | LiYANG JinBoYANG JiaCHEN GuangYaoYU PeiZHOU LeiLEI ZhenZhenWANG CatherineCYCHANG XinYingYANG TaYuanCHANG BoLiangLI | 2004 | Cell Research2004，14，4： | 24 |
| 5 | High porosity and low thermal conductivity high entropy(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2C显示文摘Porous ultra-high temperature ceramics(UHTCs)are promising for ultrahigh-temperature thermal insulation applications.However,the main limitations for their applications are the high thermal conductivity and densification of porous structure at high temperatures.In order to overcome these obstacles,herein,porous high entropy(Zr(0.2)Hf(0.2)Ti(0.2)Nb(0.2)Ta(0.2))C was prepared by a simple method combing in-situ reaction and partial sintering.Porous high entropy(Zr(0.2)Hf(0.2)Ti(0.2)Nb(0.2)Ta(0.2))C possesses homogeneous microstructure with grain size in the range of 100–500 nm and pore size in the range of 0.2–1μm,which exhibits high porosity of 80.99%,high compressive strength of 3.45 MPa,low room temperature thermal conductivity of 0.39 W·m^-1K^-1,low thermal diffusivity of 0.74 mm^2·s^-1and good high temperature stability.The combination of these properties renders porous high entropy(Zr(0.2)Hf(0.2)Ti(0.2)Nb(0.2)Ta(0.2))Cpromising as light-weight ultrahigh temperature thermal insulation materials. | Heng Chen Huimin Xiang Fu-Zhi Dai Jiachen Liu Yiming Lei Jie Zhang Yanchun Zhou | 2019 | Journal of Materials Science & Technology2019，35，8： | 16 |
| 6 | Colorectal cancer burden and trends:Comparison between China and major burden countries in the world显示文摘Objective:To summarize the colorectal cancer(CRC)burden and trend in the world,and compare the difference of CRC burden between other countries and China.Methods:Incidence and mortality data were extracted from the GLOBOCAN2018 and Cancer Incidence in Five Continents.Age-specific incidence trend was conducted by Joinpoint analysis and average annual percent changes were calculated.Results:About 1.85 million new cases and 0.88 million deaths were expected in 2018 worldwide,including 0.52 million(28.20%)new cases and 0.25 million(28.11%)deaths in China.Hungary had the highest age-standardized incidence and mortality rates in the world,while for China,the incidence and mortality rates were only half of that.CRC incidence and mortality were highly correlated with human development index(HDI).Unlike the rapid increase in Republic of Korea and the downward trend in Canada and Australia,the age-standardized incidence rates by world standard population in China and Norway were rising gradually.The age-specific incidence rate in the age group of 50-59 years in China was increasing rapidly,while in Republic of Korea and Canada,the fastest growing age group was 30-39 years.Conclusions:The variations of CRC burden reflect the difference of risk factors,as well as levels of HDI and screening(early detection activities).The burden of CRC in China is high,and the incidence of CRC continues to increase,which may lead to a sustained increase in the burden of CRC in China in the future.Screening should be expanded to control CRC,and focused on young people in China. | Jiachen Zhou Rongshou Zheng Siwei Zhang Hongmei Zeng Shaoming Wang Ru Chen Kexin Sun Minjuan Li Jianhua Gu Guihua Zhuang Wenqiang Wei | 2021 | Chinese Journal of Cancer Research2021，33，1： | 16 |
| 7 | Porous high entropy(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2: A novel strategy towards making ultrahigh temperature ceramics thermal insulating显示文摘Transition metal diborides based ultrahigh temperature ceramics(UHTCs) are characterized by high melting point, high strength and hardness, and high electrical and thermal conductivity. The high thermal conductivity arises from both electronic and phonon contributions. Thus electronic and phonon contributions must be controlled simultaneously in reducing the thermal conductivity of transition metal diborides. In high entropy(HE) materials, both electrons and phonons are scattered such that the thermal conductivity can significantly be reduced, which opens a new window to design novel insulating materials. Inspired by the high entropy effect, porous HE(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2 is designed in this work as a new thermal insulting ultrahigh temperature material and is synthesized by an in-situ thermal borocarbon reduction/partial sintering process. The porous HE(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2 possesses high porosity of 75.67%, pore size of 0.3–1.2 μm, homogeneous microstructure with small grain size of 400–800 nm, which results in low room temperature thermal diffusivity and thermal conductivity of 0.74 mm2 s^-1 and 0.51 W m^-1K^-1, respectively. In addition, it exhibits high compressive strength of3.93 MPa. The combination of these properties indicates that exploring porous high entropy ceramics such as porous HE(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2 is a novel strategy in making UHTCs thermal insulating. | Heng Chen Huimin Xiang Fu-Zhi Dai Jiachen Liu Yanchun Zhou | 2019 | Journal of Materials Science & Technology2019，35，10： | 15 |
| 8 | High entropy(Yb0.25Y0.25Lu0.25Er0.25)2SiO5 with strong anisotropy in thermal expansion显示文摘A novel high entropy(HE) rare earth monosilicate(Yb0.25Y0.25Lu0.25Er0.252 SiO5 was synthesized by solid-state reaction method.X-ray diffraction and scanning electron microscopy analysis indicate that a single solid solution is formed with homogeneous distribution of rare-earth elements.HE(Yb0.25Y0.25Lu0.255 Er0.252 SiO5 exhibits excellent phase stability and anisotropy in thermal expansion.The coefficients of thermal expansion(CTEs) in three crystallographic directions are:αa=(2.57±0.07)×10^-6 K^-1,αb=(8.07±0.13)×10^-6 K^-1,αc=(9.98±0.10)×10^-6 K^-1.The strong anisotropy in thermal expansion is favorable in minimizing the coating/substrate mismatch if preferred orientation of HE(Yb0.25Y0.25Lu0.25Er0.252 SiO5 is controlled on either metal or ceramic substrate. | Heng Chen Huimin Xiang Fu-Zhi Dai Jiachen Liu Yanchun Zhou | 2020 | Journal of Materials Science & Technology2020，36，1： | 14 |
| 9 | High entropy(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12:A novel high temperature stable thermal barrier material显示文摘Ytterbium aluminum garnet(Yb3Al5O12)is considered as a promising thermal barrier material.However,the main limitations of Yb3Al5O12 for thermal barrier applications are relative low thermal expansion coefficient and high thermal conductivity.In order to overcome these obstacles,herein,a new high entropy(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 ceramic was designed,and then powders and bulk were prepared through solid-state reaction method and spark plasma sintering(SPS),respectively.The thermal expansion coefficient of HE(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 is(8.54±0.29)×10^-6 K^-1 at 673 K–1273 K,which is about 9%higher than that of Yb3Al5O12.The thermal conductivity of HE(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 ceramic is 3.81 W·m^-1 K^-1 at 300 K,which is about 18%lower than that of Yb3Al5O12.Moreover,there is no reaction between HE(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 and thermally grown(TG)Al2O3 even at 1600℃.After annealing at 1590℃for 18 h,the average grain size of HE(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 increases only from 1.56μm to 2.27μm.Close thermal expansion coefficient to TG Al2O3,low thermal conductivity,good phase stability,excellent chemical compatibility with TG Al2O3 and slow grain growth rate make HE(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 promising for thermal barrier applications. | Heng Chen Zifan Zhao Huimin Xiang Fu-Zhi Dai Wei Xu Kuang Sun Jiachen Liu Yanchun Zhou | 2020 | Journal of Materials Science & Technology2020，47，13： | 14 |
| 10 | Three-dimensional experimental study of loose top-coal drawing law for longwall top-coal caving mining technology显示文摘Based on the loose medium flow field theory, the loose top-coal drawing law of longwall top-coal caving(LTCC) mining technology is studied by using self-developed three-dimensional(3D) test device. The loose top-coal drawing test with shields and the controlled test without shields are performed in the condition without any boundary effect. Test results show that shields will cause reduction in drawing volume of coal in the LTCC mining. The deflection phenomenon of drawing body is also observed in the controlled test, which is verified that the deflection of drawing body is caused by shield. It is found that the deflection angle decreases with increasing caving height, with the maximum value of atailand the minimum value of 0. In addition, the formula to calculate the drawing volume is proposed subsequently.The deflection of drawing body is numerically simulated using particle flow code PFC3 Dand the proposed formula to calculate drawing volume in LTCC is also verified. | Jiachen Wang Jinwang Zhang Zhengyang Song Zhaolong Li | 2015 | Journal of Rock Mechanics and Geotechnical Engineering2015，7，3： | 12 |
| 11 | Achieving strong microwave absorption capability and wide absorption bandwidth through a combination of high entropy rare earth silicide carbides/rare earth oxides显示文摘Developing electromagnetic(EM) wave absorbing materials with low reflection coefficient and optimal operating frequency band is urgently needed on account of the increasingly serious EM pollution. However, the applications of common EM absorbing materials are encumbered by poor high-temperature stability, poor oxidation resistance, narrow absorption bandwidth or high density. Herein, the strong EM absorption capability and wide efficient absorption bandwidth of high entropy ceramics are reported for the first time, which are designed by a combination of the novel high entropy(HE) rare earth silicide carbides/rare earth oxides(RE3 Si2 C2/RE2 O3). Three HE powders, i.e., HERSC-1(HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)3 Si2 C2),HERSC-2 HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)3 Si2 C2/HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)2 O3) and HERSC-3(HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)3 Si2 C2/HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)2 O3), are synthesized. Although HERSC-1 exhibits a limited absorption effect(the minimum reflection loss(RLmin) is-11.6 d B at 3.4 mm) and a relatively narrow effective absorption bandwidth(EAB) of 1.7 GHz, the optimal absorption RLminvalue and EAB of HERSC-2 and HERSC-3 are-40.7 d B(at 2.9 mm), 3.4 GHz and-50.9 d B(at 2.0 mm), 4.5 GHz,respectively, demonstrating strong microwave absorption capability and wide absorption bandwidth.Considering the better stability, low density and strong EM absorption effect, HE ceramics are promising as a new type of EM absorbing materials. | Heng Chen Biao Zhao Zifan Zhao Huimin Xiang Fu-Zhi Dai Jiachen Liu Yanchun Zhou | 2020 | Journal of Materials Science & Technology2020，47，12： | 12 |
| 12 | Deep Spectrum Prediction in High Frequency Communication Based on Temporal-Spectral Residual Network显示文摘High frequency(HF) communication is widely spread due to some merits like easy deployment and wide communication coverage. Spectrum prediction is a promising technique to facilitate the working frequency selection and enhance the function of automatic link establishment. Most of the existing spectrum prediction algorithms focus on predicting spectrum values in a slot-by-slot manner and therefore are lack of timeliness. Deep learning based spectrum prediction is developed in this paper by simultaneously predicting multi-slot ahead states of multiple spectrum points within a period of time. Specifically, we first employ supervised learning and construct samples depending on longterm and short-term HF spectrum data. Then, advanced residual units are introduced to build multiple residual network modules to respectively capture characteristics in these data with diverse time scales. Further, convolution neural network fuses the outputs of residual network modules above for temporal-spectral prediction, which is combined with residual network modules to construct the deep temporal-spectral residual network. Experiments have demonstrated that the approach proposed in this paper has a significant advantage over the benchmark schemes. | Ling Yu Jin Chen Yuming Zhang Huaji Zhou Jiachen Sun | 2018 | China Communications2018，15，9： | 9 |
| 13 | Single-shot lensless imaging with fresnel zone aperture and incoherent illumination显示文摘Lensless imaging eliminates the need for geometric isomorphism between a scene and an image while allowing the construction of compact,lightweight imaging systems.However,a challenging inverse problem remains due to the low reconstructed signal-to-noise ratio.Current implementations require multiple masks or multiple shots to denoise the reconstruction.We propose single-shot lensless imaging with a Fresnel zone aperture and incoherent illumination.By using the Fresnel zone aperture to encode the incoherent rays in wavefront-like form,the captured pattern has the same form as the inline hologram.Since conventional backpropagation reconstruction is troubled by the twin-image problem,we show that the compressive sensing algorithm is effective in removing this twin-image artifact due to the sparsity in natural scenes.The reconstruction with a significantly improved signal-to-noise ratio from a single-shot image promotes a camera architecture that is flat and reliable in its structure and free of the need for strict calibration. | Jiachen Wu Hua Zhang Wenhui Zhang Guofan Jin Liangcai Cao George Barbastathis | 2020 | Light(Science & Applications)2020，9，1： | 8 |
| 14 | Cross-Band Spectrum Prediction Based on Deep Transfer Learning显示文摘Spectrum prediction is a promising technology to infer future spectrum state by exploiting inherent patterns of historical spectrum data.In practice,for a given spectrum band of interest,when facing relatively scarce historical data,spectrum prediction based on traditional learning methods does not work well.Thus,this paper proposes a cross-band spectrum prediction model based on transfer learning.Firstly,by analysing service activities and computing the distances between various frequency points based on Dynamic Time Warping,the similarity between spectrum bands has been verified.Next,the features,which mainly affect the performance of transfer learning in the crossband spectrum prediction,are explored by leveraging transfer component analysis.Then,the effectiveness of transfer learning for the cross-band spectrum prediction has been demonstrated.Further,experimental results with real-world spectrum data demonstrate that the performance of the proposed model is better than the state-of-theart models when the historical spectrum data is limited. | Fandi Lin Jin Chen Jiachen Sun Guoru Ding Ling Yu | 2020 | China Communications2020，17，2： | 8 |
| 15 | Synthesis and catalytic performance of macroporous La1-xCexCoO3 perovskite oxide catalysts with high oxygen mobility for catalytic combustion of soot显示文摘The disordered macroporous-mesoporous La1-xCexCoO3 catalysts were prepared by complexcombustion method with ethylene glycol as complexing agent at relatively low calcination temperature.The samples were characterized by means of X-ray diffraction,N2 adsorption-ndash;desorption,Xray photoelectron spectroscopy,transmission electron microscopy,hydrogen temperature-programmed reduction and soot temperature-programmed reduction,and so on.The results show that the use of complexing agent and relatively low calcination temperature increase the specific surface area of the catalyst and have abundant pore structure.The Ce ions introduced into lattice of LaCoO3 mainly exist in the form of tetravalent.At the same time,Ce ions enhance the redox performance of the catalyst and the mobility of active oxygen species,which enhances the catalytic activity of the catalyst for soot combustion.The results of activity test show that La0.9Ce0.1CoO3 catalyst exhibits the highest activity in the absence of NO and NO2,and its T10,T50 and T90 are 371,444,and 497℃,respectively.At the same time,a possible reaction mechanism is proposed in this study based on the turnover frequency(TOF) calculated by isothermal anaerobic titrations,XPS and XRD results. | Jiachen Sun Zhen Zhao Yazhao Li Xuehua Yu Linlin Zhao Jianmei Li Yuechang Wei Jian Liu | 2020 | Journal of Rare Earths2020，38，6： | 8 |
| 16 | Failure mechanism and control technology of longwall coalface in large-cutting-height mining method显示文摘The stability control of longwall coalface is the key technology of large-cutting-height mining method.Therefore,a systematic study of the factors that affect coalface stability and its control technology is required in the development of large-cutting-height mining method in China. After the practical field observation and years of study,it was found that the more than 95% of failures in coalface are shear failure. The shear failure analysis model of coalface has been established,that can perform systematic study among factors such as mining height,coal mass strength,roof load,support resistance,and face flipper protecting plate horizontal force. Meanwhile,sensitivity analysis of factors influencing coalface stability showed that improving support capacity,cohesion of coal mass and decreasing roof load of coalface are the key to improve coalface stability. Numerical simulation of the factors affecting coalface stability has been performed using UDEC software and the results are consistent with the theoretical analysis. The coalface reinforcement technology of large-cutting-height mining method using the grouting combined with coir rope is presented. Laboratory tests have been carried out to verify its reinforcement effect and practical application has been implemented in several coal mines with good results.It has now become the main technology to reduce longwall coalface failure of large-cutting-height mining method. | Wang Jiachen Yang Shengli Kong Dezhong | 2016 | International Journal of Mining Science and Technology2016，26，1： | 7 |
| 17 | Grid-cell Aerosol Direct Shortwave Radiative Forcing Calculated Using the SBDART Model with MODIS and AERONET Observations:An Application in Winter and Summer in Eastern China显示文摘Taking winter and summer in eastern China as an example application, a grid-cell method of aerosol direct radiative forcing(ADRF) calculation is examined using the Santa Barbara DISORT Atmospheric Radiative Transfer(SBDART) model with inputs from MODIS and AERONET observations and reanalysis data. Results show that there are significant seasonal and regional differences in climatological mean aerosol optical parameters and ADRF. Higher aerosol optical depth(AOD)occurs in summer and two prominent high aerosol loading centers are observed. Higher single scattering albedo(SSA) in summer is likely associated with the weak absorbing secondary aerosols. SSA is higher in North China during summer but higher in South China during winter. Aerosols induce negative forcing at the top of the atmosphere(TOA) and surface during both winter and summer, which may be responsible for the decrease in temperature and the increase in relative humidity.Values of ADRF at the surface are four times stronger than those at the TOA. Both AOD and ADRF present strong interannual variations; however, their amplitudes are larger in summer. Moreover, patterns and trends of ADRF do not always correspond well to those of AOD. Differences in the spatial distributions of ADRF between strong and weak monsoon years are captured effectively. Generally, the present results justify that to calculate grid-cell ADRF at a large scale using the SBDART model with observational aerosol optical properties and reanalysis data is an effective approach. | Yunfei FU Jiachen ZHU Yuanjian YANG Renmin YUAN Guosheng LIU Tao XIAN Peng LIU | 2017 | Advances in Atmospheric Sciences2017，34，8： | 6 |
| 18 | Theoretical description of drawing body shape in an inclined seam with longwall top coal caving mining显示文摘Understanding the characteristics of drawing body shape is essential for optimization of drawing parameters in longwall top coal caving mining.In this study,both physical experiments and theoretical analysis are employed to investigate these characteristics and derive a theoretical equation for the drawing body shape along the working face in an inclined seam.By analyzing the initial positions of drawn marked particles,the characteristics of the drawing body shape for different seam dip angles are obtained.It is shown that the drawing body of the top coal exhibits a shape-difference and volume-symmetry characteristic,on taking a vertical line through the center of support opening as the axis of symmetry,the shapes of the drawing body on the two sides of this axis are clearly different,but their volumes are equal.By establishing theoretical models of the drawing body in the initial drawing stage and the normal drawing stage,a theoretical equation for the drawing body in an inclined seam is proposed,which can accurately describe the characteristics of the drawing body shape.The shape characteristics and volume symmetry of the drawing body are further analyzed by comparing the results of theoretical calculations and numerical simulations.It is shown that one side of the drawing body is divided into two parts by an inflection point,with the lower part being a variation development area.This variation development area increases gradually with increasing seam dip angle,resulting in an asymmetry of the drawing body shape.However,the volume symmetry coefficient fluctuates around 1 for all values of the seam dip angle variation,and the volumes of the drawing body on the two sides are more or less equal as the variation development volume is more or less equal to the cut volume.Both theoretical calculations and numerical simulations confirm that the drawing body of the top coal exhibits the shape-difference and volume-symmetry characteristic. | Jiachen Wang Weijie Wei Jinwang Zhang | 2020 | International Journal of Coal Science & Technology2020，7，1： | 6 |
| 19 | Systematic principles of surrounding rock control in longwall mining within thick coal seams显示文摘Effective surrounding rock control is a prerequisite for realizing safe mining in underground coal mines.In the past three decades, longwall top-coal caving mining(LTCC) and single pass large height longwall mining(SPLL) found expanded usage in extracting thick coal seams in China. The two mining methods lead to large void space left behind the working face, which increases the difficulty in ground control.Longwall face failure is a common problem in both LTCC and SPLL mining. Such failure is conventionally attributed to low strength and high fracture intensity of the coal seam. However, the stiffness of main components included in the surrounding rock system also greatly influences longwall face stability.Correspondingly, surrounding rock system is developed for LTCC and SPLL faces in this paper. The conditions for simultaneous balance of roof structure and longwall face are put forward by taking the stiffness of coal seam, roof strata and hydraulic support into account. The safety factor of the longwall face is defined as the ratio between the ultimate bearing capacity and actual load imposed on the coal wall.The influences provided by coal strength, coal stiffness, roof stiffness, and hydraulic support stiffness,as well as the movement of roof structure are analyzed. Finally, the key elements dominating longwall face stability are identified for improving surrounding rock control effectiveness in LTCC and SPLL faces. | Jiachen Wang Zhaohui Wang | 2019 | International Journal of Mining Science and Technology2019，29，1： | 6 |
| 20 | Signatures within esophageal microbiota with progression of esophageal squamous cell carcinoma显示文摘Objective: Esophageal squamous cell carcinoma(ESCC) is one of the dominant malignances worldwide, but currently there is less focus on the microbiota with ESCC and its precancerous lesions.Methods: Paired esophageal biopsy and swab specimens were obtained from 236 participants in Linzhou, China.Data from 16 S ribosomal RNA gene sequencing were processed using quantitative insights into microbial ecology(QIIME2) and R Studio to evaluate differences. The Wilcoxon rank sum test and Kruskal-Wallis rank sum test were used to compare diversity and characteristic genera by specimens and participant groups. Ordinal logistic regression model was used to build microbiol prediction model.Results: Microbial diversity was similar between biopsy and swab specimens, including operational taxonomic unit(OTU) numbers and Shannon index. There were variations and similarities of esophageal microbiota among different pathological characteristics of ESCC. Top 10 relative abundance genera in all groups include Streptococcus, Prevotella, Veillonella, Actinobacillus, Haemophilus, Neisseria, Alloprevotella, Rothia, Gemella and Porphyromonas. Genus Streptococcus, Haemophilus, Neisseria and Porphyromonas showed significantly difference in disease groups when compared to normal control, whereas Streptococcus showed an increasing tendency with the progression of ESCC and others showed a decreasing tendency. About models based on all combinations of characteristic genera, only taken Streptococcus and Neisseria into model, the prediction performance was the ideal one, of which the area under the curve(AUC) was 0.738.Conclusions: Esophageal biopsy and swab specimens could yield similar microbial characterization. The combination of Streptococcus and Neisseria has the potential to predict the progression of ESCC, which is needed to confirm by large-scale, prospective cohort studies. | Minjuan Li Dantong Shao Jiachen Zhou Jianhua Gu Junjie Qin Wen Chen Wenqiang Wei | 2020 | Chinese Journal of Cancer Research2020，32，6： | 4 |
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