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Numerical investigation of geostress influence on the grouting reinforcement effectiveness of tunnel surrounding rock mass in fault fracture zones

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 81-101页

作者： Xiangyu Xu zhijun Wu Lei Weng Zhaofei Chu Quansheng Liu yuan Zhou The Key Laboratory of Safety for Geotechnical and Structural Engineering of Hubei Province School of Civil EngineeringWuhan UniversityWuhan430072China Wuhan University Shenzhen Research Institute Shenzhen518057China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China Institute of Rock and Soil Mechanics Chinese Academy of SciencesWuhan430071China

Grouting is a widely used approach to reinforce broken surrounding rock mass during the construction of underground tunnels in fault fracture zones,and its reinforcement effectiveness is highly affected by geostress.In this study,a numerical manifold method(NMM)based simulator has been developed to examine the impact of geostress conditions on grouting reinforcement during tunnel excavation.To develop this simulator,a detection technique for identifying slurry migration channels and an improved fluid-solid coupling(FeS)framework,which considers the influence of fracture properties and geostress states,is developed and incorporated into a zero-thickness cohesive element(ZE)based NMM(Co-NMM)for simulating tunnel excavation.Additionally,to simulate coagulation of injected slurry,a bonding repair algorithm is further proposed based on the ZE model.To verify the accuracy of the proposed simulator,a series of simulations about slurry migration in single fractures and fracture networks are numerically reproduced,and the results align well with analytical and laboratory test results.Furthermore,these numerical results show that neglecting the influence of geostress condition can lead to a serious over-estimation of slurry migration range and reinforcement effectiveness.After validations,a series of simulations about tunnel grouting reinforcement and tunnel excavation in fault fracture zones with varying fracture densities under different geostress conditions are conducted.Based on these simula-tions,the influence of geostress conditions and the optimization of grouting schemes are discussed.

关键词： Numerical manifold method(NMM) Grouting reinforcement Geostress condition Fault fracture zone Tunnel excavation

Considerable impact of major air pollutants on hypertension in Guizhou province,southwest China

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Chinese Medical Journal 2024年第4期137卷 496-498页

作者： Ping yuan Guojia Qi Xiu Dai Xiangyuan Chu zhijun Liu Guoqin Liu Xiuquan Shi Department of Epidemiology and Health Statistics School of Public HealthZunyi Medical UniversityZunyiGuizhou 563006China School of Management Zunyi Medical UniversityZunyiGuizhou 563006China Center for Injury Research and Policy&Center for Pediatric Trauma Research The Research Institute at Nationwide Children’s HospitalThe Ohio State University College of MedicineColumbusOH 43210USA

To the Editor:Air pollution can lead to respiratory and cardiovascular diseases(CVDs),and its impact on human health is very significant.Air particles less than 0.1µm can pass through the blood brain barrier,reach the brain,and enter the central nervous system,causing physiological and pathological changes.A study shows that long-term exposure to fine particulate matter(PM_(2.5))will increase the risk of CVDs among Chinese residents.^([1])Another study found that a short time exposure to low concentrations of air pollutants may also lead to the onset of acute coronary syndrome within one hour.^([2])A meta-analysis based on seven databases showed that environmental air pollution was positively correlated with elevated blood pressure and hypertension.^([3])Mounting evidence indicates that air pollution can cause cardiovascular and cerebrovascular diseases and affect human health furtherly.

关键词： pollution impact Guizhou

CSCO guidelines for colorectal cancer version 2022:Updates and discussions

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Chinese Journal of Cancer Research 2022年第2期34卷 67-70页

作者： zhijun yuan Shanshan Weng Chenyang Ye Hanguang Hu Suzhan Zhang Ying yuan Department of Radiation Oncology Key Laboratory of Cancer Prevention and InterventionMinistry of Educationthe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009China Department of Medical Oncology the Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009China Department of Colorectal Surgery and Oncology the Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009China Cancer Center Zhejiang UniversityHangzhou 310058China

Colorectal cancer(CRC) is the third most common cancer worldwide and the second most common in tumor-related mortality by Global Cancer Statistics 2020(1). Recent data show that the incidence and mortality of CRC in C... 详细信息

关键词： mortality cancer colorectal

Pathological progression of osteoarthritis:a perspective on subchondral bone

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Frontiers of Medicine 2024年第2期18卷 237-257页

作者： Xuefei Li Wenhua Chen Dan Liu Pinghua Chen Shiyun Wang Fangfang Li Qian Chen Shunyi Lv Fangyu Li Chen Chen Suxia Guo Weina yuan Pan Li zhijun Hu Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine Shanghai200032China Research and Development Center of Chinese Medicine Resources and Biotechnology Shanghai University of Traditional Chinese MedicineShanghai201203China

Osteoarthritis(OA)is a degenerative bone disease associated with aging.The rising global aging population has led to a surge in OA cases,thereby imposing a significant socioeconomic burden.Researchers have been keenly investigating the mechanisms underlying OA.Previous studies have suggested that the disease starts with synovial inflammation and hyperplasia,advancing toward cartilage degradation.Ultimately,subchondral-bone collapse,sclerosis,and osteophyte formation occur.This progression is deemed as“top to bottom.”However,recent research is challenging this perspective by indicating that initial changes occur in subchondral bone,precipitating cartilage breakdown.In this review,we elucidate the epidemiology of OA and present an in-depth overview of the subchondral bone’s physiological state,functions,and the varied pathological shifts during OA progression.We also introduce the role of multifunctional signal pathways(including osteoprotegerin(OPG)/receptor activator of nuclear factor-kappa B ligand(RANKL)/receptor activator of nuclear factor-kappa B(RANK),and chemokine(CXC motif)ligand 12(CXCL12)/CXC motif chemokine receptor 4(CXCR4))in the pathology of subchondral bone and their role in the“bottom-up”progression of OA.Using vivid pattern maps and clinical images,this review highlights the crucial role of subchondral bone in driving OA progression,illuminating its interplay with the condition.

关键词： osteoarthritis subchondral bone OPG/RANKL/RANK CXCL12/CXCR4

Pan-cancer analysis of DNA epigenetic modifications by hydrophilic interaction liquid chromatography-tandem mass spectrometry

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Chinese Chemical Letters 2023年第7期34卷 214-218页

作者： Yiqiu Hu Xiujuan Hong zhijun yuan Jiayi Mu Xiaoxiao Zhang Zhihao Fang Ying yuan Shu Zheng Cheng Guo Cancer Institute(Key Laboratory of Cancer Prevention and Intervention China National Ministry of Education)The Second Affiliated HospitalZhejiang UniversitySchool of MedicineHangzhou310009China Cancer Center Zhejiang UniversityHangzhou 310058China

Accumulating evidence in recent years indicates that DNA methylation(5-methyl-2-deoxycytidine,5-mdC) and hydroxymethylation(5-hydroxymethyl-2-deoxycytidine, 5-hmd C) have been implicated in various biological processes, and the aberrations of these DNA cytosine modifications is tightly associated with cancer. N6-methyl-2-deoxyadenosine(m~6dA), as a newly discovered epigenetic modification in genome of mammals, has been demonstrated to play vital regulatory roles in tumorigenesis. However, the content information of m~6dA in human tumor tissues is still limited and pan-cancer analysis of these DNA epigenetic modifications is lacked. Herein, we developed a sensitive and robust stable isotopediluted hydrophilic interaction liquid chromatography-tandem mass spectrometry(HILIC-MS/MS) method for accurate quantification of m~6dA, 5-mdC and 5-hmdC in genomic DNA from 82 pairs of human tumor tissues and matched tumor-adjacent normal tissues. The types of tumors included esophagus cancer, lung cancer, breast cancer, liver cancer, pancreatic cancer, gastric cancer, stromal tumor and colorectal cancer.Compared to the normal tissues, we revealed the level of m6dA was increased in tumor tissues of esophagus cancer, lung cancer and liver cancer, whereas the level of m~6dA was diminished in tumor tissues of pancreatic cancer and gastric cancer;while the contents of 5-mdC and 5-hmdC exhibited significant decrease in tumor tissues of most types of cancer. It is worth noting that we revealed, for the first time,the content of genomic m~6dA in pancreatic cancer, stromal tumor and colorectal cancer. The significant changes of these DNA epigenetic modifications indicate they may serve as indicators of cancers. In addition, this study will benefit for better understanding of the regulatory roles of these DNA epigenetic modifications in cancers.

关键词： HILIC-MS/MS Pan-cancer analysis N~6-methyl-2-deoxyadenosine 5-Methyl-2-deoxycytidine 5-Hydroxymethyl-2-deoxycytidine

再论《水浒传》成书于嘉靖初年——以小说中的诗歌为考察中心

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中国文学研究 2024年第1期 72-76,143页

作者：杨志君长沙学院影视艺术与文化传播学院湖南长沙410005

《水浒传》第四回有一首诗(“九里山前作战场”)引自杨慎的《廿一史弹词》。根据《廿一史弹词》的编撰时间,杨慎的生平经历及《词品》中有关宋江词等相关文献,可证《水浒传》成书于嘉靖三年至十六年(1524—1537)之间。《水浒传》还有3... 详细信息

《水浒传》第四回有一首诗(“九里山前作战场”)引自杨慎的《廿一史弹词》。根据《廿一史弹词》的编撰时间,杨慎的生平经历及《词品》中有关宋江词等相关文献,可证《水浒传》成书于嘉靖三年至十六年(1524—1537)之间。《水浒传》还有3首诗中有诗句引自明中后期的诗集、笔记,可为“嘉靖说”提供佐证。“嘉靖说”有李开先《词谑》、钱希言《戏瑕》、杨慎《词品》、高儒《百川书志》、郑晓《今言》等可靠文献作为佐证,相比“元末说“”元末明初说“”明初说“”成化弘治说”,具有更充分的说服力。

关键词：《水浒传》成书时间诗歌《廿一史弹词》

Effects of sintering temperature and time on defect evolution and compression properties of Ti-Al_(3)Ti laminated composites

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Chinese Journal of Aeronautics 2022年第1期35卷 137-143页

作者： Meini yuan zhijun WANG Fangzhou HAN College of Mechatronic Engineering North University of ChinaTaiyuan 030051China

For metal-intermetallic laminated composites,various types of defects often occur during the preparation process.This paper studied the evolution and formation mechanism of defects,such as pores,tunnel cracks,and delamination cracks in Ti-Al_(3)Ti laminated composites prepared by vacuum hot-pressing method.Moreover,quasi-static and dynamic compression tests were performed to study the effects of pores and delamination cracks on the compression properties of the composites.The results showed that for Ti-Al_(3)Ti laminated composites prepared at 710℃,their Al_(3)Ti layers exhibit a porous structure,and the porosity of Al_(3)Ti layers firstly decreases and then increases under the combined action of press,the self-propagating reaction and Al3Ti grain coarsening.The tunnel cracks in Ti-Al_(3)Ti laminated composites are resulted by tensile residual stresses and the inherent brittleness of Al3Ti.For Ti-Al_(3)Ti laminated composites prepared at 680°C,the formation of delamination cracks is mainly related to the diffuse reaction of Ti/Al atoms and the Kirkendall effect,and the numbers of delamination cracks increase with the increasing of sintering time.Moreover,the pores and delamination cracks greatly deteriorate the compression properties of Ti-Al_(3)Ti laminated composites.Crack-free and dense Ti-Al_(3)Ti laminated composites exhibit the highest compression properties.

关键词： Compression strength Cracks Diffusion coefficients Laminated composites Scanning electron microscopy

面向冷启动用户的元学习与图转移学习序列推荐

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山东大学学报（工学版） 2024年第2期54卷 69-79页

作者：李璐张志军范钰敏王星袁卫华山东建筑大学计算机科学与技术学院山东济南250101

为解决推荐系统用户冷启动问题,提出面向冷启动用户的元学习与图转移学习序列推荐(sequential recommendation for cold-start users with meta graph transitional learning, MetaGTL)。MetaGTL在不使用其他辅助信息的前提下,采用图神经网络(graph neural network, GNN)建模序列间物品高阶关系生成用户物品嵌入;将交互序列构造为物品对集合,使用序列编码模块捕捉物品间的转移关系,动态建模用户兴趣;采用注意力机制,生成准确的用户特征;采用基于梯度的元学习方法训练模型,生成初始化模型;对模型的工作性能和结果进行详细分析,结合基线模型进行对比评价。试验结果表明,基于元学习与图转移学习的MetaGTL在缺少辅助信息的用户冷启动任务中具有更高的预测精度。

关键词：推荐系统序列推荐用户冷启动图神经网络元学习深度学习

含新能源和电动汽车充电站并网的主动配电网无功优化模型

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电力系统及其自动化学报 2024年第2期36卷 116-125页

作者：江智军袁轩邱文浩黄礼才何伟南昌大学信息工程学院南昌330000 国网江西省电力科学研究院南昌330000

针对新能源和电动汽车充电站规模化并网引起的无功优化问题,首先建立以主动配电网运行成本和电压偏差最小,系统稳定性最优的多目标无功优化模型。其次,基于PV曲线上、下半支解的接近程度,提出一种新的静态电压稳定性指标,以改善系统电... 详细信息

针对新能源和电动汽车充电站规模化并网引起的无功优化问题,首先建立以主动配电网运行成本和电压偏差最小,系统稳定性最优的多目标无功优化模型。其次,基于PV曲线上、下半支解的接近程度,提出一种新的静态电压稳定性指标,以改善系统电压稳定性。最后,采用具有交叉反馈机制的混合优化算法对模型进行求解,并提出一种基于Tent混沌映射和自适应变异算子的改进飞蛾扑火算法提高求解效率。仿真结果表明,所提模型在降低系统运行成本,减少电压波动的同时,还能提高系统稳定性,且该混合优化算法能够快速、准确地求解混合整数的非凸、非线性优化模型。

关键词：新能源电动汽车无功优化主动配电网混合优化算法