期刊文献+
共找到21篇文章
< 1 2 >
每页显示 20 50 100
Sliding behaviors of the trapezoidal roof rock block under a lateral dynamic disturbance
1
作者 feng dai Wancheng Zhu +2 位作者 Min Ren Shunchuan Wu Leilei Niu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期741-760,共20页
The surrounding rock of underground space is always affected by external dynamic disturbance from the side position,such as blasting vibration from a stope at the same level or seismic waves from adjacent strata.A ser... The surrounding rock of underground space is always affected by external dynamic disturbance from the side position,such as blasting vibration from a stope at the same level or seismic waves from adjacent strata.A series of laboratory tests,numerical simulations and theoretical analyses were carried out in this study to disclose the sliding mechanism of roof rock blocks under lateral disturbance.Firstly,the experiments on trapezoidal key block under various clamping loads and disturbance were conducted,followed by numerical simulations using the fast Lagrangian analysis of continua(FLAC3D).Then,based on the conventional wave propagation model and the classical shear-slip constitutive model,a theoretical model was proposed to capture the relative displacement between blocks and the sliding displacement of the key block.The results indicate that the sliding displacement of the key block increased linearly with the disturbance energy and decreased exponentially with the clamping load when the key block was disturbed to slide(without instability).Meanwhile,when the key block was disturbed to fall,two types of instability process may appear as immediate type or delayed type.In addition,the propagation of stress waves in the block system exhibited obvious low-velocity and lowfrequency characteristics,resulting in the friction reduction effect appearing at the contact interface,which is the essential reason for the sliding of rock blocks.The results can be applied to practical underground engineering and provide valuable guidance for the early detection and prevention of rockfalling disasters. 展开更多
关键词 Lateral dynamic disturbance Trapezoidal rock block system Low-velocity and low-frequency wave Friction reduction effect Instability mode
下载PDF
A fracture model for assessing tensile mode crack growth resistance of rocks 被引量:3
2
作者 Mingdong Wei feng dai +1 位作者 Yi Liu Ruochen Jiang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第2期395-411,共17页
Evaluating the fracture resistance of rocks is essential for predicting and preventing catastrophic failure of cracked structures in rock engineering.This investigation developed a brittle fracture model to predict te... Evaluating the fracture resistance of rocks is essential for predicting and preventing catastrophic failure of cracked structures in rock engineering.This investigation developed a brittle fracture model to predict tensile mode(mode I)failure loads of cracked rocks.The basic principle of the model is to estimate the reference crack corresponding to the fracture process zone(FPZ)based on the maximum normal strain(MNSN)ahead of the crack tip,and then use the effective crack to calculate the fracture toughness.We emphasize that the non-singular stress/strain terms should be considered in the description of the MNSN.In this way,the FPZ,non-singular terms and the biaxial stress state at the crack tip are simul-taneously considered.The principle of the model is explicit and easy to apply.To verify the proposed model,laboratory experiments were performed on a rock material using six groups of specimens.The model predicted the specimen geometry dependence of the measured fracture toughness well.More-over,the potential of the model in analyzing the size effect of apparent fracture toughness was discussed and validated through experimental data reported in the literature.The model was demonstrated su-perior to some commonly used fracture models and is an excellent tool for the safety assessment of cracked rock structures. 展开更多
关键词 Brittle fracture model Fracture toughness Maximum normal strain(MNSN) Fracture process zone(FPZ) Size effect
下载PDF
A 3D microseismic data-driven damage model for jointed rock mass under hydro-mechanical coupling conditions and its application 被引量:2
3
作者 Jingren Zhou Jinfu Lou +3 位作者 Jiong Wei feng dai Jiankang Chen Minsi Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第4期911-925,共15页
Rock mass is a fractured porous medium usually subjected to complex geostress and fluid pressure simultaneously.Moreover,the properties of rock mass change in time and space due to mining-induced fractures.Therefore,i... Rock mass is a fractured porous medium usually subjected to complex geostress and fluid pressure simultaneously.Moreover,the properties of rock mass change in time and space due to mining-induced fractures.Therefore,it is always challenging to accurately measure rock mass properties.In this study,a three-dimensional(3D)microseismic(MS)data-driven damage model for jointed rock mass under hydro-mechanical coupling conditions is proposed.It is a 3D finite element model that takes seepage,damage and stress field effects into account jointly.Multiple factors(i.e.joints,water and microseismicity)are used to optimize the rock mass mechanical parameters at different scales.The model is applied in Shirengou iron mine to study the damage evolution of rock mass and assess the crown pillar stability during the transition from open-pit to underground mining.It is found that the damage pattern is mostly controlled by the structure,water and rock mass parameters.The damage pattern is evidently different from the two-dimensional result and is more consistent with the field observations.This difference is caused by the MS-derived damage acting on the rock mass.MS data are responsible for gradually correcting the damage zone,changing the direction in which it expands,and promoting it to evolve close to reality.For the crown pillar,the proposed model yields a more trustworthy safety factor.In order to guarantee the stability of the pillar,it is suggested to take waterproof and reinforcement measures in areas with a high degree of damage. 展开更多
关键词 Microseismic monitoring Numerical simulation Rock damage Jointed rock mass Hydro-mechanical coupling
下载PDF
Experimental and numerical investigation on the dynamic shear failure mechanism of sandstone using short beam compression specimen
4
作者 Zelin Yan feng dai Yi Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第8期1911-1923,共13页
In this study,a novel testing method is proposed to characterize the dynamic shear property and failure mechanism of rocks by introducing the short beam compression(SBC)specimen into the split Hopkinson pressure bar(S... In this study,a novel testing method is proposed to characterize the dynamic shear property and failure mechanism of rocks by introducing the short beam compression(SBC)specimen into the split Hopkinson pressure bar(SHPB)system.Firstly,the stress distribution of SBC specimen is comprehensively analyzed by finite element method(FEM),and the results show that the optimal notch separation ratio of SBC specimen is C/H?0.2 to achieve successful dynamic simple-shear tests.Then,dynamic shear tests are conducted on sandstone using the SBC-SHPB method.Via careful pulse shaping technique,the dynamic force balance is guaranteed for SBC specimens,and the testing results show that the dynamic shear strength of sandstone is significantly rate-dependent.Combining the results of dynamic compression and tension tests,the failure envelopes of sandstone under different loading rates are obtained in the principle stress plane.It is found that the failure envelope of sandstone constantly expands outwards with increasing loading rate.Moreover,the energy partition of SBC specimen is quantified by virtue of high-speed digital image correlation(DIC)technique.The results show that the kinetic energy portion is non-negligible,and the shear fracture energy increases with increasing loading rate.In addition,the microscopic shear cracking mechanism of SBC specimen is analyzed by the thin section observation:the intra-granular(TG)fracture of minerals dominates the dynamic shear failure of sandstone,and the portion of TG fracture increases with increasing loading rate.This study provides a convenient and reliable method to investigate the dynamic shear property and failure mechanism of rocks. 展开更多
关键词 Dynamic shear property Short beam compression(SBC) Dynamic fracture energy Micro-cracking mechanism
下载PDF
原发性胆汁性胆管炎患者肝脏雌激素受体与外周血细胞因子及自身抗体的相关性分析 被引量:1
5
作者 姚煜 戴峰 徐春阳 《中国现代医学杂志》 CAS 北大核心 2021年第7期7-11,共5页
目的探讨原发性胆汁性胆管炎(PBC)患者肝脏雌激素受体(ER-α)与外周血Th1、Th2细胞因子及自身抗体的相关性。方法选择2015年12月—2017年12月南京市第二医院收治的PBC患者62例(PBC组)、自身免疫性肝炎患者60例(AIH组)及同期门诊体检健康... 目的探讨原发性胆汁性胆管炎(PBC)患者肝脏雌激素受体(ER-α)与外周血Th1、Th2细胞因子及自身抗体的相关性。方法选择2015年12月—2017年12月南京市第二医院收治的PBC患者62例(PBC组)、自身免疫性肝炎患者60例(AIH组)及同期门诊体检健康者50例(对照组)为研究对象。酶联免疫吸附试验(ELISA)检测受试者外周血Th1细胞因子[干扰素(INF-γ)、白细胞介素-2(IL-2)]、Th2细胞因子[白细胞介素-4(IL-4)、白细胞介素-10(IL-10)]的质量浓度和自身抗体(AMA-M2、抗LKM-1抗体、抗LC1抗体、抗GP210抗体、抗SLA抗体、抗SP100抗体)的阳性情况。免疫组织化学(IHC)检测PBC组、AIH组肝组织中ER-α表达情况。Pearson法分析ER-α与Th1/Th2细胞因子、自身抗体的相关性。结果3组INF-γ、IL-2、IL-4、IL-10质量浓度的比较,差异有统计学意义(P<0.05),PBC组均高于AIH组(P<0.05),AIH组均高于对照组(P<0.05)。PBC组和AIH组ER-α的阳性表达比较,差异有统计学意义(P<0.05),PBC组以高表达为主(53.23%),AIH组以低表达为主(75.00%)。PBC组ER-α与血清AMAM2、抗GP210抗体、抗SP100抗体阳性率呈正相关(r=0.530、0.602和0.652,P<0.05),与外周血INF-γ、IL-2、IL-4、IL-10呈正相关(r=0.615、0.593、0.558和0.601,均P<0.05),与抗LKM-1抗体、抗LC1抗体、抗SLA抗体无关(r=0.135、0.068和0.095,均P>0.05)。结论PBC患者肝组织中ER-α阳性表达升高,INF-γ、IL-2、IL-4、IL-10质量浓度升高,AMA-M2、抗LKM-1抗体、抗LC1抗体、抗GP210抗体、抗SP100抗体阳性表达升高,ER-α与INF-γ、IL-2、IL-4、IL-10呈正相关,ER-α与AMA-M2、抗GP210抗体、抗SP100抗体表达呈正相关。ER-α阳性表达可能是PBC发病原因之一。 展开更多
关键词 原发性胆汁性胆管炎 肝脏雌激素受体 外周血细胞因子 自身抗体
下载PDF
A review of experimental and theoretical research on the deformation and failure behavior of rocks subjected to cyclic loading 被引量:22
6
作者 Yi Liu feng dai 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第5期1203-1230,共28页
Rock engineering is highly susceptible to cyclic loads resulting from earthquakes,quarrying or rockbursts.Acquiring the fatigue properties and failure mechanism of rocks is pivotal for long-term stability assessment o... Rock engineering is highly susceptible to cyclic loads resulting from earthquakes,quarrying or rockbursts.Acquiring the fatigue properties and failure mechanism of rocks is pivotal for long-term stability assessment of rock engineering structures.So far,significant progress has been gained on the mechanical characteristics of rocks subjected to cyclic loading.For providing a global insight of typical results and main features of rocks under cyclic loading conditions,this study comprehensively reviews the state-ofthe-art of deformation and failure mechanism and fatigue constitutive relationship of rocks subjected to cyclic loading in the past 60 years.Firstly,cyclic tests on rocks are classified into different types based on loading paths,loading parameters,loading types and environment conditions.Secondly,representative results are summarized and highlighted in terms of the fatigue response of rocks,including the deformation degradation,energy dissipation,damage evolution and failure characteristics;both laboratory testing and numerical results are presented,and various measurement techniques such as X-ray microcomputed tomography(micro-CT)and digital image correlation(DIC)are considered.Thirdly,the influences of cyclic loads on the mechanical characteristics of rocks are discussed,including the cyclic stress,frequency,amplitude and waveform.Subsequently,constitutive relationships for rocks subjected to cyclic loading are outlined,in which typical fatigue constitutive models are compared and analyzed,regarding the elastoplastic model,the internal variable model,the energy-based damage model and the discrete element-based model.Finally,some ambiguous questions and prospective research are interpreted and discussed. 展开更多
关键词 Cyclic loads Mechanical properties Damage evolution Fatigue failure Constitutive relationship
下载PDF
Radiofrequency ablation or microwave ablation combined with transcatheter arterial chemoembolization in treatment of hepatocellular carcinoma by comparing with radiofrequency ablation alone 被引量:31
7
作者 Yongxiang Yi Yufeng Zhang +9 位作者 Qiang Wei Liang Zhao Jianbo Han Yan Song Ying Ding Guilan Lu Junmao Liu Huaiying Ding feng dai Xiaojun Tang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2014年第1期112-118,共7页
Objective:To compare radiofrequency ablation (RFA) or microwave ablation (MWA) and transcatheter arterial chemoembolization (TACE) with RFA or MWA monotherapy in hepatocellular carcinoma (HCC).Methods:A pros... Objective:To compare radiofrequency ablation (RFA) or microwave ablation (MWA) and transcatheter arterial chemoembolization (TACE) with RFA or MWA monotherapy in hepatocellular carcinoma (HCC).Methods:A prospective,randomized,controlled trial was conducted on 94 patients with HCC ≤7 cm at a single tertiary referral center from June 2008 to June 2010 at the Department of Hepatobiliary Surgery,the Second Affiliated Hospital of Southeast University.The patients were randomly assigned into the TACERFA or TACE-MWA (combined treatment group) and the RFA-alone or MWA-alone groups (control group).The primary end point was overall survival.The secondary end point was recurrence-free survival,and the tertiary end point was adverse effects.Results:Until the time of censor,17 patients in the TACE-RFA or TACE-MWA group had died.The median follow-up time of the patients who were still alive for the TACE-RFA or TACE-MWA group was 47.5±11.3 months (range,29 to 62 months).The 1-,3-and 5-year overall survival for the TACE-RFA or TACE-MWA group was 93.6%,68.1% and 61.7%,respectively.Twenty-five patients in the RFA or MWA group had died.The median follow-up time of the patients who were still alive for the RFA or MWA group was 47.0±12.9 months (range,28 to 62 months).The 1-,3-and 5-year overall survival for the RFA or MWA group was 85.1%,59.6% and 44.7%,respectively.The patients in the TACE-RFA or TACE-MWA group had better overall survival than the RFA or MWA group [hazard ratio (HR),0.526; 95% confidence interval (95% CO,0.334-0.823; P=0.002],and showed better recurrence-free survival than the RFA or MWA group (HR,0.582; 95% CI,0.368-0.895; P=0.008).Conclusions:RFA or MWA combined with TACE in the treatment of HCC ≤7 cm was superior to RFA or MWA alone in improving survival by reducing arterial and portal blood flow due to TACE with iodized oil before RFA. 展开更多
关键词 Radiofrequency ablation (RFA) transcatheter arterial chemoembolization (TACE) hepatocellular carcinoma (HCC)
下载PDF
Investigation of the influence of intermediate principal stress on the dynamic responses of rocks subjected to true triaxial stress state 被引量:9
8
作者 Wei You feng dai +2 位作者 Yi Liu Hongbo Du Ruochen Jiang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第5期913-926,共14页
Precisely understanding the dynamic mechanical properties and failure modes of rocks subjected to true triaxial stress state(σ1>σ2>σ3,whereσ1,σ2,andσ3 are the major principal stress,intermediate principal ... Precisely understanding the dynamic mechanical properties and failure modes of rocks subjected to true triaxial stress state(σ1>σ2>σ3,whereσ1,σ2,andσ3 are the major principal stress,intermediate principal stress,and minor principal stress,respectively)is essential to the safety of underground engineering.However,in the laboratory,it is difficult to maintain the constant true triaxial stress state of rocks during the dynamic testing process.Herein,a numerical servo triaxial Hopkinson bar(NSTHB)was developed to study the dynamic responses of rocks confronted with a true triaxial stress state,in which lateral stresses can maintain constant.The results indicate that the dynamic strength and elastic modulus of rocks increase with the rise of intermediate principal stressσ2,while the dynamic elastic modulus is independent of the dynamic strain rate.Simulated acoustic emission distributions indicate that the intermediate principal stressσ2 dramatically affects dynamic failure modes of triaxial confined rocks.Asσ2 increases,the failure pattern switches from a single diagonal shear zone into two parallel shear zones with a small slant.Moreover,a recent triaxial Hopkinson bar experimental system using three bar pairs is also numerically established,and the measuring discrepancies are identified between the two numerical bar systems.The proposed NSTHB system provides a controllable tool for studying the dynamic triaxial behavior of rocks. 展开更多
关键词 Triaxial Hopkinson bar Intermediate principal stress Dynamic strength Failure modes Numerical simulation True triaxial stress
下载PDF
Fast Marching Method for Microseismic Source Location in Cavern-Containing Rockmass: Performance Analysis and Engineering Application 被引量:16
9
作者 Ruochen Jiang feng dai +1 位作者 Yi Liu Ang Li 《Engineering》 SCIE EI 2021年第7期1023-1034,共12页
Microseismic(MS)event locations are vital aspect of MS monitoring technology used to delineate the damage zone inside the surrounding rock mass.However,complex geological conditions can impose significantly adverse ef... Microseismic(MS)event locations are vital aspect of MS monitoring technology used to delineate the damage zone inside the surrounding rock mass.However,complex geological conditions can impose significantly adverse effects on the final location results.To achieve a high-accuracy location in a complex cavern-containing structure,this study develops an MS location method using the fast marching method(FMM)with a second-order difference approach(FMM2).Based on the established velocity model with three-dimensional(3D)discrete grids,the realization of the MS location can be achieved by searching the minimum residual between the theoretical and actual first arrival times.Moreover,based on the calculation results of FMM2,the propagation paths from the MS sources to MS sensors can be obtained using the linear interpolation approach and the Runge–Kutta method.These methods were validated through a series of numerical experiments.In addition,our proposed method was applied to locate the recorded blasting and MS events that occurred during the excavation period of the underground caverns at the Houziyan hydropower station.The location results of the blasting activities show that our method can effectively reduce the location error compared with the results based on the uniform velocity model.Furthermore,the obtained MS location was verified through the occurrence of shotcrete fractures and spalling,and the monitoring results of the in-situ multipoint extensometer.Our proposed method can offer a more accurate rock fracture location and facilitate the delineation of damage zones inside the surrounding rock mass. 展开更多
关键词 Fast marching method Microseismic event location Cavern-containing complex rock mass Runge-Kutta method
下载PDF
Application of machine learning in predicting the rate-dependent compressive strength of rocks 被引量:9
10
作者 Mingdong Wei Wenzhao Meng +1 位作者 feng dai Wei Wu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第5期1356-1365,共10页
Accurate prediction of compressive strength of rocks relies on the rate-dependent behaviors of rocks, and correlation among the geometrical, physical, and mechanical properties of rocks. However, these properties may ... Accurate prediction of compressive strength of rocks relies on the rate-dependent behaviors of rocks, and correlation among the geometrical, physical, and mechanical properties of rocks. However, these properties may not be easy to control in laboratory experiments, particularly in dynamic compression experiments. By training three machine learning models based on the support vector machine(SVM), backpropagation neural network(BPNN), and random forest(RF) algorithms, we isolated different input parameters, such as static compressive strength, P-wave velocity, specimen dimension, grain size, bulk density, and strain rate, to identify their importance in the strength prediction. Our results demonstrated that the RF algorithm shows a better performance than the other two algorithms. The strain rate is a key input parameter influencing the performance of these models, while the others(e.g. static compressive strength and P-wave velocity) are less important as their roles can be compensated by alternative parameters. The results also revealed that the effect of specimen dimension on the rock strength can be overshadowed at high strain rates, while the effect on the dynamic increase factor(i.e. the ratio of dynamic to static compressive strength) becomes significant. The dynamic increase factors for different specimen dimensions bifurcate when the strain rate reaches a relatively high value, a clue to improve our understanding of the transitional behaviors of rocks from low to high strain rates. 展开更多
关键词 Machine learning Rock dynamics Compressive strength Strain rate
下载PDF
Experimental and numerical investigation on the mechanical responses and cracking mechanism of 3D confined single-flawed rocks under dynamic loading 被引量:2
11
作者 Wei You feng dai Yi Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第2期477-493,共17页
Accurately characterizing the mechanical responses and cracking mechanism of three-dimensional confined fractured rocks under coupled static-dynamic loading is of paramount importance for underground engineering const... Accurately characterizing the mechanical responses and cracking mechanism of three-dimensional confined fractured rocks under coupled static-dynamic loading is of paramount importance for underground engineering construction.Using a modified split Hopkinson pressure bar(SHPB)system,five groups of single-flawed specimens with the axial prestress ratio from 0 to 0.8 are tested at the strain rates in the range of 65-205 s-1under a fixed radial prestress.Our results indicate that both the dynamic strength and total strength show significant positive linear correlations with the strain rate,and the dynamic strength shows more strain rate sensitivity under higher axial prestress.The dynamic strength and corresponding failure strain decrease with increasing axial prestress,while the total strength is barely affected by the axial prestress.The dynamic elastic modulus initially increases before the axial prestress ratio reaches 0.6 and then decreases.The failure pattern of tested specimens changes from single diagonal failure to an“X”shaped conjugated failure as axial prestress increases.Furthermore,the progressive cracking processes of confined single-flawed specimens under different axial prestresses are numerically visualized by the discrete element method(DEM).Based on the displacement trend lines on both sides of cracking surface,five crack types are identified and classified in our simulation.The displacement field distributions of the DEM models reveal that the macroscopic single diagonal failure under lower axial prestress is mainly controlled by mixed tensile-shear cracks,while the“X”shaped conjugated failure under higher axial prestress is shear dominated. 展开更多
关键词 Confined flawed rock Split hopkinson pressure bar(SHPB) Cracking mechanism Discrete element method(DEM)
下载PDF
提升高职院校教师信息化教学效果的策略研究 被引量:3
12
作者 代锋 《西北成人教育学院学报》 2019年第1期10-14,共5页
在当前信息通信技术和教育信息化进程飞速发展的背景下,高等职业院校教师信息化教学运用与推广是信息时代职业教育改革难得契机和不可逆转的发展趋势。正是基于信息化教学效果视角,结合高等职业院校教师教学实际,全面阐述高职院校教师... 在当前信息通信技术和教育信息化进程飞速发展的背景下,高等职业院校教师信息化教学运用与推广是信息时代职业教育改革难得契机和不可逆转的发展趋势。正是基于信息化教学效果视角,结合高等职业院校教师教学实际,全面阐述高职院校教师信息化教学的现状,同时进行初步的原因分析,并在此基础上探究提升高职院校教师信息化教学效果的可靠路径,以促进高职院校教育软实力不断凸显。 展开更多
关键词 高职院校 信息化教学 提升策略
下载PDF
RECENT PROGRESS ON SPHERICAL HARMONIC APPROXIMATION MADE BY BNU RESEARCH GROUP -In memory of Professor Sun Yongsheng
13
作者 Kunyang Wang feng dai 《Analysis in Theory and Applications》 2007年第1期50-63,共14页
As early as in 1990, Professor Sun Yongsheng, suggested his students at Beijing Normal University to consider research problems on the unit sphere. Under his guidance and encouragement his students started the researc... As early as in 1990, Professor Sun Yongsheng, suggested his students at Beijing Normal University to consider research problems on the unit sphere. Under his guidance and encouragement his students started the research on spherical harmonic analysis and approximation. In this paper, we incompletely introduce the main achievements in this area obtained by our group and relative researchers during recent 5 years (2001-2005). The main topics are: convergence of Cesaro summability, a.e. and strong summability of Fourier-Laplace series; smoothness and K-functionals; Kolmogorov and linear widths. 展开更多
关键词 spherical harmonics Fourier-Laplace expansion convergence APPROXIMATION SMOOTHNESS K-FUNCTIONAL width
下载PDF
Clinical significance of serum sB7-H3 and IL-1 in patients with hepatitis B related hepatocellular carcinoma
14
作者 feng dai Shou-zhong Fu +4 位作者 Bin Wang Wei Ding Xiao-wei Wang Jian-dong Shen Meng-jie Yin 《Journal of Hainan Medical University》 2019年第19期57-61,共5页
Objective: To explore the clinical significance of serum sB7-H3 and IL-1 in patients with hepatitis B associated hepatocellular carcinoma. Methods: 122 cases of patients with hepatitis B related liver diseases admitte... Objective: To explore the clinical significance of serum sB7-H3 and IL-1 in patients with hepatitis B associated hepatocellular carcinoma. Methods: 122 cases of patients with hepatitis B related liver diseases admitted to our hospital from January 2015 to June 2018 were selected, including 47 cases of patients with hepatitis B related hepatocellular carcinoma, 41 cases of patients with hepatitis B related cirrhosis and 34 cases of patients with hepatitis B virus, and 45 cases of healthy persons in the same period as normal control group. The serum sB7-H3, IL-1α, IL-1β levels were compared among the four groups. The relationship between serum sB7-H3, IL-1α, IL-1β and clinicopathological characteristics was analyzed, and the correlation of sB7-H3, IL-1α and IL-1β was analyzed by Pearson method. The efficacy of serum sB7-H3, IL-1α, IL-1β in early diagnosis and prognostic evaluation for hepatitis B associated hepatocellular carcinoma were analyzed by ROC and Logistic regression analysis. Results: The serum sB7-H3, IL-1α, IL-1β levels in the four groups were in order from high to low: hepatitis B related hepatocellular carcinoma>hepatitis B related cirrhosis>hepatitis B virus>normal control group, all above had statistical difference (P<0.05). The high levels of serum sB7-H3, IL-1α, IL-1β were significantly correlated with TNM stage, alpha fetoprotein level and lymph node metastasis (P<0.05). Spearman correlation analysis results showed that the serum level of sB7-H3 was positively correlated with IL-1α and IL-1β(r=0.837, 0.756;P<0.05), the serum level of IL-1α was positively correlated with IL-1β(r=0.734, P<0.05). The ROC curve and Logistic regression analysis showed that the AUC of sB7-H3, IL-1α, IL-1β and combined detection for the diagnosis of hepatitis B associated hepatocellular carcinoma was 0.893, 0.887, 0.881, 0.961 (P<0.05), respectively;the AUC of sB7-H3, IL-1α, IL-1β and combined detection for the prognostic evaluation for hepatitis B associated hepatocellular carcinoma was 0.843, 0.837, 0.834, 0.917, respectively. Conclusion:Serum sB7-H3, IL-1α, IL-1β levels could all be used for the early diagnosis and prognostic evaluation of hepatitis B associated hepatocellular carcinoma, and the combined detection is more effective, which has important clinical significance. 展开更多
关键词 Hepatitis B related hepatocellular carcinoma sB7-H3 IL-1 DIAGNOSIS Prognostic evaluation
下载PDF
Jackson-type inequalities on high-dimensional spheres
15
作者 Yeli Niu feng dai 《Science China Mathematics》 SCIE CSCD 2024年第11期2571-2586,共16页
We study Jackson's inequality on high-dimensional spheres with respect to the modulus of smoothness defined via the rotation group.We obtain a version of Jackson's inequality with a dimensionfree constant,exte... We study Jackson's inequality on high-dimensional spheres with respect to the modulus of smoothness defined via the rotation group.We obtain a version of Jackson's inequality with a dimensionfree constant,extending Newman and Shapiro's well-known results in 1964 from the case of r=1 and p=∞to more general cases.Our results partially overcome the curse of dimensionality.We also establish similar results on the equivalence of the K-functional and modulus of smoothness. 展开更多
关键词 modulus of smoothness K-FUNCTIONAL Jackson's inequality high-dimensional approximation
原文传递
Transarterial chemoembolization with PD-(L)1 inhibitors plus molecular targeted therapies for hepatocellular carcinoma(CHANCE001) 被引量:41
16
作者 Hai-Dong Zhu Hai-Liang Li +61 位作者 Ming-Sheng Huang Wei-Zhu Yang Guo-Wen Yin Bin-Yan Zhong Jun-Hui Sun Zhi-Cheng Jin Jian-Jian Chen Nai-Jian Ge Wen-Bin Ding Wen-Hui Li Jin-Hua Huang Wei Mu Shan-Zhi Gu Jia-Ping Li Hui Zhao Shu-Wei Wen Yan-Ming Lei Yu-Sheng Song Chun-Wang Yuan Wei-Dong Wang Ming Huang Wei Zhao Jian-Bing Wu Song Wang Xu Zhu Jian-Jun Han Wei-Xin Ren Zai-Ming Lu Wen-Ge Xing Yong Fan Hai-Lan Lin Zi-Shu Zhang Guo-Hui Xu Wen-Hao Hu Qiang Tu Hong-Ying Su Chuan-Sheng Zheng Yong Chen Xu-Ya Zhao Zhu-Ting Fang Qi Wang Jin-Wei Zhao Ai-Bing Xu Jian Xu Qing-Hua Wu Huan-Zhang Niu Jian Wang feng dai Dui-Ping feng Qing-Dong Li Rong-Shu Shi Jia-Rui Li Guang Yang Hai-Bin Shi Jian-Song Ji Yu-E Liu Zheng Cai Po Yang Yang Zhao Xiao-Li Zhu Li-Gong Lu Gao-Jun Teng 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2023年第3期1198-1207,共10页
There is considerable potential for integrating transarterial chemoembolization(TACE),programmed death-(ligand)1(PD-[L]1)inhibitors,and molecular targeted treatments(MTT)in hepatocellular carcinoma(HCC).It is necessar... There is considerable potential for integrating transarterial chemoembolization(TACE),programmed death-(ligand)1(PD-[L]1)inhibitors,and molecular targeted treatments(MTT)in hepatocellular carcinoma(HCC).It is necessary to investigate the therapeutic efficacy and safety of TACE combined with PD-(L)1 inhibitors and MTT in real-world situations.In this nationwide,retrospective,cohort study,826 HCC patients receiving either TACE plus PD-(L)1 blockades and MTT(combination group,n=376)or TACE monotherapy(monotherapy group,n=450)were included from January 2018 to May 2021.The primary endpoint was progression-free survival(PFS)according to modified RECIST.The secondary outcomes included overall survival(OS),objective response rate(ORR),and safety.We performed propensity score matching approaches to reduce bias between two groups.After matching,228 pairs were included with a predominantly advanced disease population.Median PFS in combination group was 9.5 months(95%confidence interval[CI],8.4-11.0)versus 8.0 months(95%CI,6.6-9.5)(adjusted hazard ratio[HR],0.70,P=0.002).OS and ORR were also significantly higher in combination group(median OS,19.2[16.1-27.3]vs.15.7 months[13.0-20.2];adjusted HR,0.63,P=0.001;ORR,60.1%vs.32.0%;P<0.001).Grade 3/4 adverse events were observed at a rate of 15.8%and 7.5%in combination and monotherapy groups,respectively.Our results suggest that TACE plus PD-(L)1 blockades and MTT could significantly improve PFS,OS,and ORR versus TACE monotherapy for Chinese patients with predominantly advanced HCC in real-world practice,with an acceptable safety profile. 展开更多
关键词 HEPATOCELLULAR TARGETED MATCHING
原文传递
南通市介入相关医务人员工作压力研究
17
作者 于劲松 顾建平 +6 位作者 李海鹏 戴锋 朱慧 黄瑛 吴海燕 吴靓 范春琴 《中华介入放射学电子杂志》 2023年第3期275-278,共4页
目的了解介入相关医务人员工作压力现状,探索工作压力的影响因素,为提高介入相关医务人员社会心理健康及工作状态的干预措施相关研究提供参考。方法编制《介入相关医务人员工作压力现状调查问卷》,采用一般人口学资料调查表、工作压力... 目的了解介入相关医务人员工作压力现状,探索工作压力的影响因素,为提高介入相关医务人员社会心理健康及工作状态的干预措施相关研究提供参考。方法编制《介入相关医务人员工作压力现状调查问卷》,采用一般人口学资料调查表、工作压力源量表对南通市所有三级医院介入相关医务人员进行问卷调查,收集相关数据,并通过采用SPSS 24.0统计软件进行数据分析,包括独立样本t检验、方差分析以及回归分析等。结果采用Likert 5分计分法分非常同意、同意、无意见、不同意、非常不同意5个选项,分别赋予5至1分值,得分如下:南通市三级医院介入相关医务人员工作压力得分(3.78±0.806),处于偏高水平,排在前三位的是来自工作负荷得分(3.54±0.85),外部环境得分(3.45±0.87),组织管理得分(3.20±0.74),其他维度得分分别是职业前景得分(2.73±0.87),医患关系得分(2.71±0.83),工作兴趣得分(2.68±0.68),人际关系得分(2.04±0.85)。结论南通市介入相关医务人员工作压力较大,主要压力源来自工作负荷、外部环境和组织管理方面的压力。36~40岁的介入相关医务人员工作压力要高于其他年龄组,男性高于女性,减轻工作压力,提高心理健康水平,有助于减少介入相关医务人员的职业倦怠。 展开更多
关键词 介入相关 医务人员 工作压力
原文传递
Experimental and numerical simulation on the sliding process of roof rock blocks triggered by dynamic disturbance
18
作者 feng dai Wancheng Zhu +2 位作者 Min Ren Leilei Niu Chen Hou 《Underground Space》 SCIE EI CSCD 2023年第3期269-293,共25页
With the excavation of underground opening,the roof rock block may fall under external dynamic disturbance.In this paper,the roof rock mass was simplified as a rock block system composed of trapezoidal rock blocks.A s... With the excavation of underground opening,the roof rock block may fall under external dynamic disturbance.In this paper,the roof rock mass was simplified as a rock block system composed of trapezoidal rock blocks.A series of experiments and numerical simulations were performed to study the sliding process of the key block under the horizontal static clamping load and vertical impact disturbance.The propagation of stress wave in the block system were captured and analyzed by using high-speed camera and digital image correlation technique.The results reveal that a pendulum-type wave was generated due to the propagation and superposition of stress waves in the block system.Therefore,the governing mechanism of the sliding displacement of the key block was clarified based on the propagation of incident stress waves or pendulum-type waves.Meanwhile,it is found that the sliding distance of the key block decreases in a power function with the increasing friction coefficient,or decreases in a parabolic function with the increasing trapezoid internal angle.Finally,a case study on the roof block sliding of the roadway at a gold mine was conducted,and it is concluded that the sliding of the key block resulted from the coupled effects of"shear driving"and"low friction"driven by stress wave propagation,regardless of a single or multi-layer rock block system.These results may provide technical guideline for preventing rock-falling accidents caused by blasting distur-bances in underground mining. 展开更多
关键词 Roof rock block Sliding instability Dynamic disturbance Pendulum-type wave Digital image correlation technique Numerical simulation
原文传递
Excavation-induced microseismicity: microseismic monitoring and numerical simulation 被引量:9
19
作者 Nu-wen XU Chun-an TANG +4 位作者 Hong LI feng dai Ke MA Jing-dong SHAO Ji-chang WU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2012年第6期445-460,共16页
The volume of influence of excavation at the right bank slope of Dagangshan Hydropower Station, southwest China, is essentially determined from microseismic monitoring, numerical modeling and conventional measurements... The volume of influence of excavation at the right bank slope of Dagangshan Hydropower Station, southwest China, is essentially determined from microseismic monitoring, numerical modeling and conventional measurements as well as in situ observations. Microseismic monitoring is a new application technique for investigating microcrackings in rock slopes. A micro- seismic monitoring network has been systematically used to monitor rock masses unloading relaxation due to continuous exca- vation of rock slope and stress redistribution caused by dam impoundment later on, and to identify and delineate the potential slippage regions since May, 2010. An important database of seismic source locations is available. The analysis of microseismic events showed a particular tempo-spatial distribution. Seismic events predominantly occurred around the upstream slope of 1180 m elevation, especially focusing on the hanging wall of fault XL316-1. Such phenomenon was interpreted by numerical modeling using RFPA-SRM code (realistic failure process analysis-strength reduction method). By comparing microseismic activity and results of numerical simulation with in site observation and conventional measurements results, a strong correlation can he obtained between seismic source locations and excavation-induced stress distribution in the working areas. The volume of influence of the rock slope is thus determined. Engineering practices show microseismic monitoring can accurately diagnose magnitude, intensity and associated tempo-spatial characteristics of tectonic activities such as faults and unloading zones. The integrated technique combining seismic monitoring with numerical modeling, as well as in site observation and conventional surveying, leads to a better understanding of the internal effect and relationship between microseismic activity and stress field in the right bank slope from different perspectives. 展开更多
关键词 Microseismic monitoring Rock slope Numerical simulation Stability analysis Dagangshan Hydropower Station
原文传递
汽车玻璃单位产品能耗及相关标准的研究 被引量:2
20
作者 冯岱 田力 余侃 《中国建材》 2020年第11期123-125,共3页
研究背景2017年,各地工信委应国家工信部要求,依据《平板玻璃单位产品能源消耗限额》(GB 21340—2013)对浮法玻璃能耗指标进行稽查。从实际的稽查结果来看,绝大多数平板玻璃生产企业能够达到能耗限额的要求,但全年生产汽车玻璃的浮法线... 研究背景2017年,各地工信委应国家工信部要求,依据《平板玻璃单位产品能源消耗限额》(GB 21340—2013)对浮法玻璃能耗指标进行稽查。从实际的稽查结果来看,绝大多数平板玻璃生产企业能够达到能耗限额的要求,但全年生产汽车玻璃的浮法线除1条新投产的生产线勉强合格以外,全部超出限额要求。 展开更多
关键词 浮法玻璃 平板玻璃 汽车玻璃 单位产品能耗 能耗指标 能耗限额 浮法线 稽查
原文传递
上一页 1 2 下一页 到第
使用帮助 返回顶部