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基于起伏界面走时校正的三维最短路径射线追踪方法

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地球物理学报 2025年第2期68卷 578-594页

作者：秦泽光赵爱华徐涛姚时中国地震局地球物理研究所北京100081 中国科学院地质与地球物理研究所深层油气理论与智能勘探开发重点实验室北京100029 中国科学院大学北京100049

最短路径射线追踪方法来源于图理论,可以获得最小走时路径,是初至波和反射波走时成像的重要正演模拟方法之一.最短路径法通常以规则网格离散速度模型,规则网格难以精确表征起伏地表和地下弯曲界面,因而计算的走时精度不是很高.减小网格... 详细信息

最短路径射线追踪方法来源于图理论,可以获得最小走时路径,是初至波和反射波走时成像的重要正演模拟方法之一.最短路径法通常以规则网格离散速度模型,规则网格难以精确表征起伏地表和地下弯曲界面,因而计算的走时精度不是很高.减小网格尺寸可以减小计算误差,但同时会增加计算时间,对于三维模型尤其如此.为此,本文针对三维模型提出一种基于规则网格的走时校正方法:当地震射线传播至或起始于边界节点(近似表征界面的模型节点)时,将走时校正为射线传播至或起始于边界节点所对应界面节点(模型节点网格线与界面的交点)的走时.应用走时校正技术后可以基本消除由界面近似引起的反射波走时误差,并且可改善射线路径分布.数值模型计算结果表明:走时校正方法所用计算时间基本保持在和常规算法相同的量级,但走时校正方法可提高反射波的走时精度约1~2个数量级.

关键词：射线追踪最短路径算法规则网格起伏界面走时校正

一种基于插值技术高精度计算稀疏网格地震定位中震源轨迹的方法

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地球物理学报 2021年第7期64卷 2347-2361页

作者：赵爱华中国地震局地球物理研究所北京100081

区域和全球地震定位越来越多地基于更接近实际的横向非均匀速度模型.速度模型主要来自于地震体波层析成像结果,分辨率不是很高.这样,模型宜于以稀疏网格剖分以减少计算时间和计算机内存需求.当剖分的模型单元较大时,基于射线追踪技术计... 详细信息

区域和全球地震定位越来越多地基于更接近实际的横向非均匀速度模型.速度模型主要来自于地震体波层析成像结果,分辨率不是很高.这样,模型宜于以稀疏网格剖分以减少计算时间和计算机内存需求.当剖分的模型单元较大时,基于射线追踪技术计算复杂介质地震定位中震源轨迹的方法——选取震源轨迹所经过单元节点(位于单元中心,称为震源轨迹节点)为轨迹参考点,利用最小走时树射线追踪方法计算绝对残差场中连接轨迹参考点的射线路径作为震源轨迹——计算结果误差较大,难以满足精定位需要.针对该问题,本文对其进行了改进:不将震源轨迹节点作为轨迹参考点,而是基于插值技术计算每个轨迹节点其法线点对(即该节点与其周围残差正负极性不同的相邻节点组成的点对中梯度绝对值最大的那对)间残差为零的点作为震源轨迹参考点.算例表明:和原方法相比,改进方法计算的震源轨迹更为精细,计算精度提高数十(线性插值)至数百倍(非线性插值),而计算效率基本保持在同一数量级,使利用震源轨迹进行直观、快速和高精度的区域或全球地震事件定位成为可能;壳幔界面反射纵波(PmP)对震源的约束和直达纵波(Pg)相似;同一台站PmP-Pg波到时差约束的震源轨迹对震源深度有很好的约束.

关键词：地震定位稀疏网格震源轨迹射线追踪插值

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三维复杂速度模型中地震事件震源轨迹的计算

地球物理学报 2018年第10期61卷 3994-4006页

作者：赵爱华中国地震局地球物理研究所北京100081

地球内部三维速度图像的广泛建立为进行高精度的地震定位提供了良好条件.使用震源轨迹确定震源位置不仅稳健而且直观,但三维复杂速度模型中的震源轨迹难以给出解析解.为此,本文提出了一种较准确地计算三维复杂速度模型中震源轨迹的数值... 详细信息

地球内部三维速度图像的广泛建立为进行高精度的地震定位提供了良好条件.使用震源轨迹确定震源位置不仅稳健而且直观,但三维复杂速度模型中的震源轨迹难以给出解析解.为此,本文提出了一种较准确地计算三维复杂速度模型中震源轨迹的数值方法.根据震源轨迹在残差场中的特点:(1)震源轨迹位于残差正负极性彼此不同的邻点之间;(2)绝对梯度在震源轨迹的法线方向最大;(3)在法线方向上越靠近震源轨迹残差绝对值越小,对于每个模型节点分别和残差正负极性与其不同的邻点组成的点对,将其中绝对梯度最大的点对作为震源轨迹法线点对,选取法线点对中残差绝对值较小的点(即震源轨迹所在模型单元的节点)作为震源轨迹代表点;在绝对残差场中数值较小的连通区域(可能有多个)内,利用最小走时树算法依次计算出每个连通区域中地震波从绝对残差最小点至同一连通区域内震源轨迹代表点的射线路径作为震源轨迹.算例表明:本文方法适用于三维复杂速度模型,对震源轨迹的稳定性及构成段数没有限制,计算的震源轨迹精细且较完整、可用于高精度的地震定位.

关键词：地震定位震源轨迹射线追踪最小走时树方法三维速度模型

Functional Metabolomics Reveals that Astragalus Polysaccharides Improve Lipids Metabolism through Microbial Metabolite 2-Hydroxybutyric Acid in Obese Mice

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Engineering 2022年第2期8卷 111-122页

作者： Bingbing Li Ying Hong Yu Gu Shengjie Ye Kaili Hu Jian Yao Kan Ding aihua zhao Wei Jia Houkai Li Institute of Interdisciplinary Integrative Medicine Research Shanghai University of Traditional Chinese MedicineShanghai 201203China Shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai 201203China Shanghai Key Laboratory of Diabetes Mellitus and Center for Translational Medicine Shanghai Jiao Tong University Affiliated Sixth People’s HospitalShanghai 200233China University of Hawaii Cancer Center HonoluluHI 96813USA

Polysaccharides are widely present in herbs with multiple activities,especially immunity regulation and metabolic benefits for metabolic ***,the underlying mechanisms are not well *** metabolomics is increasingly used to investigate systemic effects on the host by iden-tifying metabolites with particular *** study explores the mechanisms underlying the metabolic benefits of Astragalus polysaccharides(APS)by adopting a functional metabolomics *** effects of APS were determined in eight-week high-fat diet(HFD)-fed obese ***,gas chromatography–time-of-flight mass spectrometry(GC–TOFMS)-based untargeted metabolomics was performed for an analysis of serum and liver tissues,and liquid chromatography–tandem mass spectrom-etry(LC–MS/MS)-based targeted metabolomics was *** potential functions of the metabo-lites were tested with in vitro and in vivo models of metabolic *** results first confirmed the metabolic benefits of APS in obese ***,metabolomics analysis revealed that APS supplemen-tation reversed the HFD-induced metabolic changes,and identified 2-hydroxybutyric acid(2-HB)as a potential functional metabolite for APS activity that was significantly decreased by a HFD and reversed by *** study indicated that 2-HB inhibited oleic acid(OA)-induced triglyceride(TG)*** was also found to stimulate the expression of proteins in lipid degradation in hepatocytes and TG lipolysis in 3T3-L1 ***,it was found to reduce serum TG and regulate the proteins involved in lipid degradation in high-fat and high-sucrose(HFHS)-fed *** conclusion,our study demonstrates that the metabolic benefits of APS are at least partially due to 2-HB generation,which modulated lipid metabolism both in vitro and in *** results also highlight that functional metabolomics is practical for investigating the mechanism underlying the systemic benefits of plant polysaccharides.

关键词： Astragalus polysaccharides(APS) Functional metabolomics 2-Hydroxybutyric acid Obesity

Soil fungal community is more sensitive to nitrogen deposition than increased rainfall in a mixed deciduous forest of China

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Soil Ecology Letters 2020年第1期2卷 20-32页

作者： aihua zhao Lei Liu Baodong Chen Wei Fu Wei Xie Tianle Xu Wei Zhang Qing Ye Haiyan Feng Shenglei Fu State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Institute of Ecology Jiangsu Key Laboratory of Agricultural MeteorologyNanjing University of Information Science&TechnologyNanjing 210044China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions College of Environment and PlanningHenan UniversityKaifeng 475004China

Nitrogen(N)deposition and intensified rainfall can strongly affect soil microbial community,but compared with available studies on bacteria,those on soil fungi are quite *** we carried out a field experiment in a mixed deciduous forest of China to study the influences of increased N deposition and rainfall on soil fungi by using quantitative PCR and high-throughput sequencing *** results demonstrated that(1)N addition significantly increased fungal abundance and alpha diversity(richness,Shannon index and Invsimpson index),changed fungal community composition at OTU level,and marginally increased the relative abundance of Ascomycota and Zygomycota,while water addition showed no remarkable effects on fungal abundance,biodiversity and community composition.(2)N addition significantly increased the richness of saprotrophic fungi and pathogenic fungi,and the relative abundance of saprotrophic fungi,but water addition only slightly increased the abundance of pathogenic fungi.(3)Fungal composition dissimilarity closely correlated with the disparity of soil parameters as a *** NH_(4)^(+)-N exhibited strong positive correlation with the richness of pathogenic fungi and mycorrhizal fungi,while both soil moisture and NH_(4)^(+)-N tightly correlated with soil fungal abundance and alpha diversity *** concluded that in this N-limited but non-water-limited forest ecosystem,N deposition posed stronger effects on soil fungi than increased rainfall,partially mediated by changes in soil properties.

关键词： Climate change Fungi Functional group Saprotrophic fungi Pathogenic fungi Mycorrhizal fungi

MicroRNA-125b Induces Cancer Cell Apoptosis Through Suppression of Bcl-2 Expression

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Journal of Genetics and Genomics 2012年第1期39卷 29-35页

作者： aihua zhao Quan Zeng Xiaoyan Xie Junnian Zhou Wen Yue Yali Li Xuetao Pei Department of Obstetrics and Gynecology General Hospital of PLABeijing 100853China Stem Cell and Regenerative Medicine Lab Beijing Institute of Transfusion MedicineBeijing 100850China Department of Obstetrics and Gynecology The 309th Hospital of PLABeijing 100091China

MicroRNAs （miRNAs） are small, noncoding RNAs which can often act as an oncogene or a tumor suppressor. Several miRNAs are associated with the development of hepatoceUular carcinoma （HCC）. We demonstrated that miR-125b significantly suppresses HCC cell proliferation and promotes apoptosis by inhibiting the gene expression of the anti-apoptotic protein, Bcl-2. Bioinformatic analysis indicated that the 3tUTR of Bcl-2 has binding sites for miR-I25b, Luciferase reporter assay confirmed the ability of miR-125b to dramatically suppress Bcl-2 transcription, suggesting that Bcl-2 is a target gene for miR-125b. We concluded that miR-125b acts as a tumor suppressor in hepatic tumor development by targeting Bcl-2 and inducing cancer celt apoptosis.

关键词： miR-125b Bcl-2 Apoptosis Proliferation

An intersection method for locating earthquakes in complex velocity models

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Applied Geophysics 2007年第4期4卷 294-300页

作者：赵爱华丁志峰中国地震局地球物理研究所北京100081

The intersection method is one of the basic approaches for locating earthquakes and is not only robust but also efficient. However, its location accuracy is not high, especially for focal depth because the velocity model used for the conventional intersection method is based on homogeneous or laterally homogeneous media, which is too simple. In order to improve the accuracy, we have modified the existing intersection method. In the modified approach, the earthquake loci are not assumed to be circular or hyperbolic and calculation accuracy is improved using a minimum traveltime tree algorithm for tracing rays. The numerical model shows that the modified method can locate earthquakes in complex velocity models.

关键词： Earthquake location intersection method ray tracing minimum traveltime tree algorithm

利用环境噪声自相关研究唐海—商都台阵测线下方的莫霍面深度

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地震学报 2024年第1期46卷 47-68页

作者：魏红谱赵爱华中国地震局地球物理研究所北京100081

基于唐海—商都宽频带地震台阵2006—2009年连续三年的波形记录,利用环境噪声相位自相关函数对台阵下方的莫霍面反射P波进行分析。通过对同一个台站多个时间段的自相关结果进行分组、采用两步叠加处理增加信号强度:(1)在组内进行线性叠... 详细信息

基于唐海—商都宽频带地震台阵2006—2009年连续三年的波形记录,利用环境噪声相位自相关函数对台阵下方的莫霍面反射P波进行分析。通过对同一个台站多个时间段的自相关结果进行分组、采用两步叠加处理增加信号强度:(1)在组内进行线性叠加,对组间的叠加结果进行相位加权叠加;(2)基于华北地区的背景速度结构信息,在地壳平均速度5%不确定性的时窗内,根据自相关函数包络线的二阶导数最大值确定P波的莫霍面反射时间,经时间-深度转化,获得台阵下方的莫霍面深度。结果显示,莫霍面从东南向西北总体由浅变深,中间有小幅度的起伏。噪声自相关方法确定的莫霍面平均深度相较于参考的接收函数结果的偏差为0.8 km,相应的双程走时偏差约为0.3 s。以月份叠加的自相关函数结果显示,PmP信号的噪声源具有显著的季节性变化。自相关函数的波形特征显示华北地区的地壳-地幔转换带的速度梯度模式不同。

关键词：华北地区莫霍面深度环境噪声相位自相关反射P波

妊娠期糖尿病孕产妇疾病不确定感与社会支持、应对方式的关系

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中国健康心理学杂志 2021年第9期29卷 1319-1322页

作者：赵爱华赵静河南省濮阳市人民医院产科 457300 濮阳市人民医院麻醉科手术部

目的:探讨妊娠期糖尿病(GDM)孕产妇疾病不确定感与社会支持、应对方式的关系,为临床促进孕产妇身心健康发展提供理论基础。方法:选取某院2018年3月—2020年1月就诊治疗的GDM孕产妇105例作为研究对象。采用Mishel疾病不确定感量表(MUIS)... 详细信息

目的:探讨妊娠期糖尿病(GDM)孕产妇疾病不确定感与社会支持、应对方式的关系,为临床促进孕产妇身心健康发展提供理论基础。方法:选取某院2018年3月—2020年1月就诊治疗的GDM孕产妇105例作为研究对象。采用Mishel疾病不确定感量表(MUIS)、社会支持评定量表(SSRS)、简易应对方式问卷(SCSQ)对所有孕产妇进行调查,并分析孕产妇的疾病不确定感与社会支持及应对方式的关系。结果:GDM孕产妇疾病不确定感总评分范围为54~118分,平均(90.36±15.26)分。社会支持总评分范围为22~38分,平均(29.29±4.38)分。积极应对评分范围为14~31分,平均(22.92±6.54)分。消极应对评分范围为11~22分,平均(16.48±3.56)分。支持利用度、社会支持总评分与信息缺乏性均呈负相关(r=-0.372,-0.365;P<0.05),且支持利用度、社会支持总评分与疾病不确定感总评分均呈负相关(r=-0.412,-0.405;P<0.05)。消极应对与不明确性之间呈正相关(r=0.365,P<0.05),且消极应对与疾病不确定感总评分之间呈正相关(r=0.386,P<0.05)。结论:GDM孕产妇的疾病不确定感与社会支持水平均处于中等水平,有待提高,且存在消极应对方式的孕产妇。社会支持与疾病不确定感呈负相关,消极应对与疾病不确定感呈正相关。

关键词：妊娠期糖尿病疾病不确定感社会支持应对方式