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Estimating the grain size of microgranular material using laser-induced breakdown spectroscopy combined with machine learning algorithms

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Plasma Science and Technology 2024年第5期26卷 129-137页

作者：张朝李亚举杨光辉曾强李小龙陈良文钱东斌孙对兄苏茂根杨磊张少锋马新文 Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province College of Physics and Electronic EngineeringNorthwest Normal UniversityLanzhou 730070People’s Republic of China Advanced Energy Science and Technology Guangdong LaboratoryHuizhou 516000People’s Republic of China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000People’s Republic of China University of the Chinese Academy of Sciences Beijing 100049People’s Republic of China School of Nuclear Science and Technology University of the Chinese Academy of SciencesBeijing 100049People’s Republic of China

Recent work has validated a new method for estimating the grain size of microgranular materials in the range of tens to hundreds of micrometers using laser-induced breakdown spectroscopy(LIBS).In this situation,a piecewise univariate model must be constructed to estimate grain size due to the complex dependence of the plasma formation environment on grain size.In the present work,we tentatively construct a unified calibration model suitable for LIBS-based estimation of those grain sizes.Specifically,two unified multivariate calibration models are constructed based on back-propagation neural network(BPNN)algorithms using feature selection strategies with and without considering prior information.By detailed analysis of the performances of the two multivariate models,it was found that a unified calibration model can be successfully constructed based on BPNN algorithms for estimating the grain size in the range of tens to hundreds of micrometers.It was also found that the model constructed with a priorguided feature selection strategy had better prediction performance.This study has practical significance in developing the technology for material analysis using LIBS,especially when the LIBS signal exhibits a complex dependence on the material parameter to be estimated.

关键词： laser-induced breakdown spectroscopy machine learning randomly packed microgranular materials

Advances in the role of follicular T helper cells in graft versus host diseases

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Liver Research 2017年第2期1卷 131-134页

作者： maogen chen Xiaohong Lin Julie Wang Nancy Olsen Song Guo Zheng Division of Immunology and Rheumatology Keck School of Medicine at University of Southern CaliforniaCAUSA Organ Transplant Center First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Guangdong Provincial Key Laboratory of Organ Donation and Transplant Immunology GuangzhouChina Guangdong Provincial International Cooperation Base of Science and Technology(Organ Transplantation) GuangzhouChina Center for Clinical Immunology at Sun Yat-sen University GuangzhouChina Division of General Surgery The Eastern Hospital of the First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Division of Rheumatology Penn State Milton S.Hershey Medical CenterHersheyPAUSA

Graft versus host disease(GVHD)is a refractory complication of allogeneic hematopoietic stem cell transplantation for the treatment of malignant and non-malignant hematopoietic diseases.Inflammatory cascade responses and cellular immune reactions are the major factors underlying GVHD pathogenesis.Cells producing the cytokine,interleukin(IL)-21 are crucial players involved in injured tissues in GVHD patients.Besides T helper 17 cells,follicular T helper(Tfh)cells are a new source of IL-21 and play a vital role in GVHD pathogenesis.Tfh cell function is mostly regulated by T-follicular regulatory(Tfr)cells that are also located in the germinal center.This review highlights recent advances in the role of Tfh and Tfr cell function in GVHD pathogenesis.New insights are provided into the potential for clinical application in GVHD prevention and treatment.

关键词： Graft versus host disease(GVHD) Allogeneic hematopoietic stem cell transplantation Interleukin-21 Follicular T helper(Tfh)cell

Phenotypic and functional characteristic of a newly dentified CDS＋Foxp3-CDI03＋ regulatory T cells

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Journal of Molecular Cell Biology 2014年第1期8卷 81-92页

作者： Ya Liu Qin Lan Ling Lu maogen chen Zanxian Xia Jilin Ma Julie Wang Huimin Fan Yi Shen Bernhard Ryffel David Brand Francisco Quismorio Zhongmin Liu David A. Horwitz Anping Xu Song Guo Zheng Department of Nephrology Sun Yat-sen Memorial Hospital of Sun Yat-sen University Guangzhou 510120 China Division of Rheumatology and Immunology Department of Medicine University of Southern California Keck School of Medicine Los Angeles CA 90033 USA Institute of Immunology Shanghai East Hospital at Tongji University Shanghai200120 China University of Orleans and CNRS UMR7355 3b rue de la Ferollerie Orleans 45071 France Veterans Affairs Medical Center Memphis TN 38104 USA

TGF-β and Foxp3 expressions are crucial for the induction and functional activity of CD4(+)Foxp3(+) regulatory T (iTreg) cells. Here, we demonstrate that although TGF-β-primed CD8(+) cells display much lower Foxp3 expression, their suppressive capacity is equivalent to that of CD4(+) iTreg cells, and both Foxp3(-) and Foxp3(+) CD8+ subsets have suppressive activities in vitro and in vivo. CD8(+)Foxp3(-) iTreg cells produce little IFN-γ but almost no IL-2, and display a typical anergic phenotype. Among phenotypic markers expressed in CD8(+)Foxp3(-) cells, we identify CD103 expression particularly crucial for the generation and function of this subset. Moreover, IL-10 and TGF-β signals rather than cytotoxicity mediate the suppressive effect of this novel Treg population. Therefore, TGF-β can induce both CD8(+)Foxp3(-) and CD8(+)Foxp3(+) iTreg subsets, which may represent the unique immunoregulatory means to treat autoimmune and inflammatory diseases.

关键词：调节性T细胞细胞表型功能特征 CDS TGF-β eg细胞抑制活性自身免疫

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东海西湖Y地区三维地震采集设计及应用效果

物探化探计算技术 2024年第1期46卷 45-56页

作者：周静毅刘宏扬陈茂根徐翠娥中国石化上海海洋油气分公司勘探开发研究院上海200120 中国石化海洋石油工程有限公司物探分公司上海200135

东海西湖凹陷Y地区位于凹陷东侧边缘部位,跨白堤深洼和东部断阶带,地质条件复杂。结合已经发现油气的西湖凹陷斜坡带、中央背斜带的储层发育特征,认为Y地区主要目的层为渐新统花港组和始新统平湖组,沉积岩为主,岩性为砂、泥岩,除此之外... 详细信息

东海西湖凹陷Y地区位于凹陷东侧边缘部位,跨白堤深洼和东部断阶带,地质条件复杂。结合已经发现油气的西湖凹陷斜坡带、中央背斜带的储层发育特征,认为Y地区主要目的层为渐新统花港组和始新统平湖组,沉积岩为主,岩性为砂、泥岩,除此之外还发育火山岩体。主要目的层埋深花港组在2 500 m~5 000 m之间。Y地区存在二维地震资料信噪比、目的层分辨率不够、基底成像不清楚等问题。为精细落实圈闭和岩体描述提高三维地震资料品质,开展了Y地区的三维地震采集设计论证,从分辨率、面元尺寸、时间采样率、偏移孔径、震源、电缆沉放深度等方面进行了详细的论证和分析,提出了适合Y地区的采集参数,此三维地震采集技术的应用表明,实际采集三维地震数据较二维地震数据有较宽的频带,而且资料品质得到较大提高,同相轴连续性、断裂更清晰,信噪比更高。

关键词：西湖凹陷圈闭落实采集设计分辨率面元偏移孔径

Epithelioid Hemangioendothelioma of the Liver:Etiology,Natural History and Treatment

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Chinese Journal of Clinical Oncology 2008年第4期5卷 306-308页

作者： Weirong chen maogen chen Gaoyang Cai Ziqun Liao Department of General Surgery the Second Hospital of Medical College of Shantou University Shantou 515041 Guangdong Province. China.

Introduction Epithelioid hemangioendothelioma(EHE)is an uncommon vascular tumor,which also has been called histiocytoid haemangioma.This low-grade malignant tumor was first described as a distinctive entity in 1982 by... 详细信息

关键词：上皮血管内皮瘤治疗方法病因学临床表现

冷却方式对高温后不同类型混凝土残余力学性能的影响研究

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实验力学 2022年第1期37卷 52-62页

作者：陈宗平班茂根周济广西大学土木建筑工程学院广西南宁530004 广西大学工程防灾与结构安全教育部重点实验室广西南宁530004

为了揭示高温后不同冷却方式对高强、普通及再生混凝土力学性能的影响,以历经温度和冷却方式为变化参数,对灾后的三类混凝土进行单轴抗压试验研究,获取了试件的质量变化率以及轴心受压应力-应变曲线,对比分析了高温后不同冷却方式下3种... 详细信息

为了揭示高温后不同冷却方式对高强、普通及再生混凝土力学性能的影响,以历经温度和冷却方式为变化参数,对灾后的三类混凝土进行单轴抗压试验研究,获取了试件的质量变化率以及轴心受压应力-应变曲线,对比分析了高温后不同冷却方式下3种混凝土试件的峰值应力、峰值应变、弹性模量等力学性能指标的影响规律和能量耗散规律。结果表明:喷水冷却下的再生混凝土受骨料影响,其质量变化率及峰值应变在400℃以下时相对常温为递减趋势;在温度超过400℃后,自然冷却下的峰值应变均比喷水冷却的大,曲线下降段相比喷水冷却的更缓;冷却方式对高强及普通混凝土的抗压强度和弹性模量影响不显著,而对再生混凝土影响较大;温度较低时,普通混凝土的抗压强度和弹性模量退化最快,而温度较高时,再生混凝土退化最快。基于试验结果,提出高温后不同冷却方式下3种混凝土的抗压强度计算式,计算式的决定系数R平方值均大于0.75,表明模型拟合效果较好。

关键词：冷却方式高温混凝土残余力学性能退化规律

Significance of extracellular signal-regulated kinase (ERK) in the development of rectal carcinoma

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The Chinese-German Journal of Clinical Oncology 2008年第1期7卷 27-30页

作者： Weirong chen Ziqun Liao maogen chen Gaoyang Cai Tinghan Li Department of General Surgery Second Affiliated Hospital of Shantou University Medical College Shantou 515041 China

Objective: To study the ERK expression and its significance in the development of human rectal carcinoma. Methods: Samples were obtained from 62 patients with rectal carcinoma, including tumor tissue and adjacent normal rectal tissue. Western blot was used to measure the expression of ERK-1 and ERK-2. S-P immunohistochemical method was used to count the microvessel density (MVD). Results: ERK-1 and ERK-2 protein levels were increased in rectal carcinoma tissue compared with those in adjacent normal tissues (t = 2.980 and 2.194, P < 0.01 and 0.05 respectively). The MVD was higher in patients with higher ERK-1 and/or ERK-2 protein levels than that in cases with lower ERK-1 and/or ERK-2 levels. Conclu- sion: Overexpression of ERK-1 and/or ERK-2 may play an important role in the development of human rectal carcinoma, the overexpression can enhance the growth of tumor microvessel and promote the development of human rectal carcinoma.

关键词：细胞外信号激酶直肠癌临床治疗

东海陆架盆地西湖凹陷平北地区含煤地层岩性圈闭识别

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石油实验地质 2022年第5期44卷 755-760页

作者：牛华伟刘苗蒋涔朱立新陈茂根中国石化上海海洋油气分公司上海200120

东海陆架盆地西湖凹陷平北地区主要目的层始新统平湖组沉积受潮汐作用影响较大,薄砂体多层叠置、横向变化快,煤层发育。目的层埋深普遍超过3500 m,储层物性相对较差。现有地震资料深层信噪比低、能量弱,砂泥阻抗特征差异小,储层预测及... 详细信息

东海陆架盆地西湖凹陷平北地区主要目的层始新统平湖组沉积受潮汐作用影响较大,薄砂体多层叠置、横向变化快,煤层发育。目的层埋深普遍超过3500 m,储层物性相对较差。现有地震资料深层信噪比低、能量弱,砂泥阻抗特征差异小,储层预测及刻画难度大。在深层保幅宽频处理资料的基础上,按照明确岩性圈闭发育类型、精细砂体描述、落实岩性圈闭目标的整体思路开展研究,明确了古地貌背景、砂体模式及岩性圈闭发育类型,在这一格架约束下开展精细的砂体描述工作,应用地震波形、地震反射结构特征、叠前反演弹性属性相结合预测砂体,并利用叠后统计学反演预测煤层分布,提高了砂体描述的精度和可靠性。

关键词：保幅宽频处理地震反射结构叠前同时反演地质统计学反演西湖凹陷东海陆架盆地

高温喷水冷却后圆钢管高强混凝土的界面黏结性能试验研究

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湖南大学学报（自然科学版） 2021年第3期48卷 75-87页

作者：陈宗平周济陈建佳班茂根广西大学土木建筑工程学院广西南宁530004 工程防灾与结构安全教育部重点实验室(广西大学) 广西南宁530004

为研究高温喷水冷却后圆钢管高强混凝土界面间的黏结性能,设计22个圆钢管试件进行高温喷水冷却处理后的静力推出试验,主要考虑混凝土强度、历经最高温度、锚固长度、恒温时长和冷却方式的影响.通过试验揭示了高温喷水冷却后圆钢管高强... 详细信息

为研究高温喷水冷却后圆钢管高强混凝土界面间的黏结性能,设计22个圆钢管试件进行高温喷水冷却处理后的静力推出试验,主要考虑混凝土强度、历经最高温度、锚固长度、恒温时长和冷却方式的影响.通过试验揭示了高温喷水冷却后圆钢管高强混凝土界面黏结失效机理,分析了各变化参数对其黏结性能的影响,并提出高温喷水冷却后圆钢管高强混凝土黏结强度的计算公式.结果表明:高温喷水冷却后试件加载端与自由端的荷载滑移曲线变化趋势基本相似,并可将其分为三类典型曲线;推出试验中钢管外表面应变与距加载端的距离呈指数关系分布;高温喷水冷却后,试件的黏结强度随混凝土强度的增大变化较小,与锚固长度成反比,恒温时长大于60 min后基本稳定,随历经最高温度的升高,极限黏结强度先增大后减小再增大,残余黏结强度先增大再减小;与自然冷却试件相比,喷水冷却试件的极限黏结强度、残余黏结强度与剪切黏结刚度均较小,界面耗能能力较大.运用文中所提出的黏结强度计算公式算得的结果与试验值吻合良好.

关键词：高温喷水冷却后圆钢管高强混凝土黏结强度滑移性能