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Nanoscale resetting of the Th/Pb system in an isotopically-closed monazite grain: A combined atom probe and transmission electron microscopy study 被引量:3
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作者 A.-M.Seydoux-Guillaume D.Fougerouse +3 位作者 A.T.Laurent E.Gardés S.M.Reddy D.W.Saxey 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第1期65-76,共12页
Understanding the mechanisms of parent-daughter isotopic mobility at the nanoscale is key to rigorous interpretation of Ue The Pb data and associated dating. Until now, all nanoscale geochronological studies on geolog... Understanding the mechanisms of parent-daughter isotopic mobility at the nanoscale is key to rigorous interpretation of Ue The Pb data and associated dating. Until now, all nanoscale geochronological studies on geological samples have relied on either Transmission Electron Microscope(TEM) or Atom Probe Microscopy(APM) characterizations alone, thus suffering from the respective weaknesses of each technique. Here we focus on monazite crystals from a ~1 Ga, ultrahigh temperature granulite from Rogaland(Norway). This sample has recorded concordant UeP b dates(measured by LA-ICP-MS) that range over 100 My, with the three domains yielding distinct isotopic Ue Pb ages of 1034 ± 6 Ma(D1; Srich core), 1005 ± 7 Ma(D2), and 935 ± 7 Ma(D3), respectively. Combined APM and TEM characterization of these monazite crystals reveal phase separation that led to the isolation of two different radiogenic Pb(Pb*) reservoirs at the nanoscale. The S-rich core of these monazite crystals contains Cae Srich clusters, 5 -10 nm in size, homogenously distributed within the monazite matrix with a mean interparticle distance of 40 -60 nm. The clusters acted as a sink for radiogenic Pb(Pb*) produced in the monazite matrix, which was reset at the nanoscale via Pb diffusion while the grain remained closed at the micro-scale. Compared to the concordant ages given by conventional micro-scale dating of the grain,the apparent nano-scale age of the monazite matrix in between clusters is about 100 Myr younger, which compares remarkably well to the duration of the metamorphic event. This study highlights the capabilities of combined APM-TEM nano-structural and nano-isotopic characterizations in dating and timing of geological events, allowing the detection of processes untraceable with conventional dating methods. 展开更多
关键词 MONAZITE NANOSCALE resetTING NANO-CLUSTERS APM TEM UHT METAMORPHISM
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Integral Representations for the Price of Vanilla Put Options on a Basket of Two-Dividend Paying Stocks
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作者 Sunday Emmanuel Fadugba Chuma Raphael Nwozo 《Applied Mathematics》 2015年第5期783-792,共10页
This paper presents integral representations for the price of vanilla put options, namely, European and American put options on a basket of two-dividend paying stocks using integral method based on the double Mellin t... This paper presents integral representations for the price of vanilla put options, namely, European and American put options on a basket of two-dividend paying stocks using integral method based on the double Mellin transform. We show that by the decomposition of the integral equation for the price of American basket put option, the integral equation for the price of European basket put option can be obtained directly. 展开更多
关键词 BLACK-SCHOLES Partial differential Equation Double Mellin Transform Early Exercise PREMIUM VANILLA Basket put OPTION
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Evaluation of call options
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作者 陈道平 《Journal of Chongqing University》 CAS 2002年第2期89-92,共4页
The European and American call options, for which the prices of their underlying asset follow compound Poisson process, are evaluated by a probability method. Formulas that can be used to evaluate the options are obta... The European and American call options, for which the prices of their underlying asset follow compound Poisson process, are evaluated by a probability method. Formulas that can be used to evaluate the options are obtained, which include not only the elements of an option: the price of the call option, the exercise price and the expiration date, but also the riskless interest rate, nevertheless exclude the volatility of the underlying asset. In practice, the evaluated results obtained by these formulas can provide references of making strategic decision for an investor who buys the call option and a company who sells the call option. 展开更多
关键词 call option exercise price underlying asset compound Poisson process potential no loss probability
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Pricing Catastrophe Options with Credit Risk in a Regime-Switching Model
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作者 XU Yajuan WANG Guojing 《应用概率统计》 CSCD 北大核心 2024年第4期572-587,共16页
In this paper,we consider the price of catastrophe options with credit risk in a regime-switching model.We assume that the macroeconomic states are described by a continuous-time Markov chain with a finite state space... In this paper,we consider the price of catastrophe options with credit risk in a regime-switching model.We assume that the macroeconomic states are described by a continuous-time Markov chain with a finite state space.By using the measure change technique,we derive the price expressions of catastrophe put options.Moreover,we conduct some numerical analysis to demonstrate how the parameters of the model affect the price of the catastrophe put option. 展开更多
关键词 PRICING catastrophe option credit risk REGIME-SWITCHING measure change
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Extensive Resetting of Feldspar Pb Isotopic Composition in Archean–Paleoproterozoic Granitic Rocks from the Kongling Terrane,South China:Implications for Tracing Thermal Evolutionary History
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作者 MENG Fanxue LU Jie +2 位作者 ZOU Zongqi GUO Jingliang MENG Yuanku 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期386-398,共13页
Feldspar Pb isotopes have been widely used to trace magmatic formation and evolution processes.However,it remains unclear whether post-magmatic thermal events can affect feldspar Pb isotopic ratios.Here,the in situ Pb... Feldspar Pb isotopes have been widely used to trace magmatic formation and evolution processes.However,it remains unclear whether post-magmatic thermal events can affect feldspar Pb isotopic ratios.Here,the in situ Pb isotopic composition of feldspar hosted in granitic rocks(thirteen Archean and one Paleoproterozoic)from the northern Kongling terrane,Yangtze Craton,South China,is analyzed.The samples reveal a substantial variation in their Pb isotopic composition,spanning the gap between the 1.9 Ga and present-day geochrons,which indicates extensive resetting by later tectonothermal events.This resetting was interpreted to have likely resulted from Paleoproterozoic and Neoproterozoic tectonothermal events related to the assembly and breakup of the Columbia and Rodinia supercontinents.These results suggest that Pb isotopes should be used cautiously when tracing magma sources and petrogenesis in magmatic rocks that have experienced post-magmatic reworking.However,the in situ Pb isotopic composition of feldspar in ancient granitoids may also potentially be used to reveal later tectonothermal events.The extensive resetting of the Pb isotopic composition in feldspar by regional thermal events may also provide new insights into our understanding of the Pb isotope paradox. 展开更多
关键词 in situ Pb isotope Pb isotope resetting thermal event Archean-Paleoproterozoic Kongling terrane
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Modeling the Spatio-Temporal Dynamics of Local Context for a Contextualized Diffusion of Agroecological Intensification Options in Niger
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作者 Nouhou Salifou Jangorzo Maud Loireau +3 位作者 Abou-Soufianou Sadda Ousmane Sami Mari Abdoul-Aziz Saïdou Hassane Bil-Assanou Issoufou 《International Journal of Geosciences》 CAS 2024年第3期270-301,共32页
Spatio-temporal variability and dynamics in Sahelian agro-pastoral zones make each local situation a special case. These specificities must be considered to guide the dissemination of agricultural options with a view ... Spatio-temporal variability and dynamics in Sahelian agro-pastoral zones make each local situation a special case. These specificities must be considered to guide the dissemination of agricultural options with a view to sustainable development. The territorial scale of municipalities is not sufficient for this necessary contextualization;the scale of the “village terroir” seems to be a better option. This is the hypothesis we put forward in the framework of the Global Collaboration for Resilient Food Systems program (CRFS), i.e. local context is spatially defined by village terroir. The study is based on data collected through participatory mapping and surveys in “village terroirs” in three regions of Niger (Maradi, Dosso and Tillabéri). Then the links between farm managers and their cultivated land, as well as the spatio-temporal dynamics of local context are analyzed. This study provides evidence of the existence and functional usefulness of the village terroir for farmers, their land management and their activities. It demonstrates the usefulness of contextualizing agricultural options at this scale. Their analysis elucidates the links between “terroirs village” and the specific functioning of the agrosocio-ecosystems acting on each of them, thus laying the systemic and geographical foundations for a model of the spatio- temporal dynamics of “village terroirs”. This initial work has opened up new perspectives in modeling and sustainable development. 展开更多
关键词 NIGER Option by Context Local Condition Complex System Multiscale Conceptual Modeling
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Robust H_∞ output feedback controller design for linear uncertain discrete-time switched systems via state reset
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作者 赵旭东 凌明祥 +1 位作者 曾庆双 杜晶晶 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第3期328-332,共5页
This paper studies the problem of robust H∞ output feedback controller via state-reset for linear uncertain discrete-time switched systems. Using multiple Lyapunov functions,we address an output feedback controller u... This paper studies the problem of robust H∞ output feedback controller via state-reset for linear uncertain discrete-time switched systems. Using multiple Lyapunov functions,we address an output feedback controller under arbitrary switching signals,in which an H∞ performance is required. The condition is shown in the form of linear matrix inequalities (LMI). Finally,a numerical example shows the feasibility of the designed controller and illustrates that the new sufficient condition has lower conservation and more optimized H∞ tfperformance. 展开更多
关键词 linear discrete-time switched systems state-reset H∞ performance low conversation multiple Lvaounov functions
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GLOBAL CIVILIZATION INITIATIVE HELPS RESET THE GLOBAL ORDER
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作者 Ong Tee Keat 《China Report ASEAN》 2024年第5期62-63,共2页
The rollout of the Global Civilization Initiative(GCI)in 2023 introduced a new public good to humanity.This Chinese initiative has driven home a clear message that all nations have the right to choose their own develo... The rollout of the Global Civilization Initiative(GCI)in 2023 introduced a new public good to humanity.This Chinese initiative has driven home a clear message that all nations have the right to choose their own development paths in their pursuit of modernization,which is not necessarily synonymous with Westernization,as demonstrated by China’s example. 展开更多
关键词 reset PURSUIT necessarily
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Research on Value Evaluation Method of Investment Project Based on Fuzzy Composite Real Options
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作者 Huanyu Li 《Economics World》 2024年第1期24-34,共11页
Venture capital investments are characterized by high input,high yield,and high risk.Due to the complexity of the market environment,stage-by-stage investment is becoming increasingly important.Traditional evaluation ... Venture capital investments are characterized by high input,high yield,and high risk.Due to the complexity of the market environment,stage-by-stage investment is becoming increasingly important.Traditional evaluation methods like comparison,proportion,maturity,internal rate of return,scenario analysis,decision trees,and net present value cannot fully consider the uncertainty and stage characteristics of the project.The fuzzy real options method addresses this by combining real option theory,fuzzy number theory,and composite option theory to provide a more accurate and objective evaluation of Public-Private Partnership(PPP)projects.It effectively considers the interaction of options and the ambiguity of project parameters,making it a valuable tool for project evaluation in the context of venture capital investment. 展开更多
关键词 real option fuzzy method Geske composite option
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磁阻式磁强计的SET/RESET电路设计及应用 被引量:10
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作者 孙雪峰 熊沈蜀 +1 位作者 周兆英 朱荣 《电测与仪表》 北大核心 2003年第7期22-25,共4页
SET/RESET电路是配合磁阻式磁强计使用的必不可少的外围电路之一,本文阐述了SET/RESET功能的原理,分析了设计SET/RESET电路的出发点,介绍了SET/RESET电路的一个实例,并且将它应用于微型方位水平仪,取得了良好的效果。
关键词 磁阻式磁强计 SET/reset电路 微型方位水平仪 电路设计
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高精度磁阻式罗盘及其SET/RESET电路设计 被引量:4
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作者 宋宇宁 周兆英 《仪器仪表学报》 EI CAS CSCD 北大核心 2006年第z2期1513-1514,共2页
本文介绍用磁阻式磁强计设计的磁罗盘的设计,以及其SET/RESET电路的设计。详细分析磁阻式磁强计的特点和使用要点,根据对大地磁场进行的分析,对航向角的解算算法进行推导,并重点介绍如何根据载体的俯仰角、滚转角来获取精确的航向角。... 本文介绍用磁阻式磁强计设计的磁罗盘的设计,以及其SET/RESET电路的设计。详细分析磁阻式磁强计的特点和使用要点,根据对大地磁场进行的分析,对航向角的解算算法进行推导,并重点介绍如何根据载体的俯仰角、滚转角来获取精确的航向角。试验数据和曲线也同时进行介绍。 展开更多
关键词 罗盘 磁阻式磁强计 SET reset
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Ge_2Sb_2Te_5不同晶相对相变存储单元RESET电流影响 被引量:2
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作者 王玉婵 康杰虎 王玉菡 《电子元件与材料》 CAS CSCD 2016年第1期61-63,共3页
相变存储器(Phase Change Memory,PCM)的RESET电流是决定其功耗的最重要参数。基于相变材料Ge_2Sb_2Te_5(GST)的PCM单元,不同的SET条件下晶粒表现出两种不同的晶态结构,分别为立方晶相和六方晶相。针对这两种不同晶态结构的晶粒,应用数... 相变存储器(Phase Change Memory,PCM)的RESET电流是决定其功耗的最重要参数。基于相变材料Ge_2Sb_2Te_5(GST)的PCM单元,不同的SET条件下晶粒表现出两种不同的晶态结构,分别为立方晶相和六方晶相。针对这两种不同晶态结构的晶粒,应用数值模拟计算,对PCM单元的RESET电流进行研究,并将模拟结果与实际测试结果对比验证。结果表明:基于立方晶粒GST的PCM单元需要的RESET电流更小。 展开更多
关键词 相变存储器 Ge2Sb2Te5 reset 数值计算 立方晶相 六方晶相
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基于并发Options的双边多议题协商模型优化 被引量:2
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作者 彭志平 彭宏 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2007年第9期95-100,共6页
针对双边多议题协商中的僵局问题,提出利用并发Options优化协商模型的方法.这种方法可在不降低双边协商效用的前提下,并行动态优化与僵局议题相关的多个议题的保留值.电子商务的实验结果表明:基于并发Options的协商模型优化方法是有效的... 针对双边多议题协商中的僵局问题,提出利用并发Options优化协商模型的方法.这种方法可在不降低双边协商效用的前提下,并行动态优化与僵局议题相关的多个议题的保留值.电子商务的实验结果表明:基于并发Options的协商模型优化方法是有效的;无论是学习速度,还是最佳策略的优化程度和泛化能力,该方法均明显优于基于标准Options和Q-学习的优化方法. 展开更多
关键词 协商模型 协商僵局 优化 并发options 强化学习
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磁阻传感器中SET/RESET充磁电路的分析 被引量:14
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作者 孔庆新 张朝晖 +1 位作者 蓝金辉 王立锦 《仪器仪表学报》 EI CAS CSCD 北大核心 2005年第z2期118-119,共2页
介绍了HONEYWELL公司HMC系列磁阻传感器的关键部分——Set/Reset充磁电路。并对其在实际电路中应用时的电平不匹配问题进行了讨论,对4种电路方案进行了详细的分析,并总结了在设计、试验该电路过程中的经验。
关键词 磁阻传感器 充磁电路 电路分析
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相变存储单元RESET电流与电极尺寸关系的数值模拟
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作者 王玉菡 王玉婵 徐霞 《固体电子学研究与进展》 CAS CSCD 北大核心 2016年第6期442-445,共4页
应用数值模拟计算方法对相变存储器单元RESET电流和加热电极尺寸关系进行了研究,建立了二维存储单元模型,模拟了电脉冲作用下不同电极尺寸相变存储单元的RESET过程,包括不同电极尺寸相变单元RESET过程的温度场分布和电阻-电流关系。模... 应用数值模拟计算方法对相变存储器单元RESET电流和加热电极尺寸关系进行了研究,建立了二维存储单元模型,模拟了电脉冲作用下不同电极尺寸相变存储单元的RESET过程,包括不同电极尺寸相变单元RESET过程的温度场分布和电阻-电流关系。模拟结果表明,RESET电流随着电极尺寸减小而急剧减小。 展开更多
关键词 相变存储器 数值模拟 reset 电极尺寸
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一种融合Options与蚁群算法的虚拟机自适应配置方法
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作者 彭志平 周晓柯 孙志毅 《小型微型计算机系统》 CSCD 北大核心 2015年第4期801-805,共5页
为了提高云环境的可靠性,对虚拟资源的管理是一个关键.针对虚拟机的自适应配置问题,提出一种分层强化学习Options和蚁群优化算法融合的方法 A-HRL.该方法记录蚂蚁遍历过程中留下的信息素,利用信息素变化率引入粗糙度概念,并根据粗糙度... 为了提高云环境的可靠性,对虚拟资源的管理是一个关键.针对虚拟机的自适应配置问题,提出一种分层强化学习Options和蚁群优化算法融合的方法 A-HRL.该方法记录蚂蚁遍历过程中留下的信息素,利用信息素变化率引入粗糙度概念,并根据粗糙度阈值创建子目标实现任务分层.将A-HRL算法应用于虚拟机自适应配置中,通过创建任务组和虚拟机可用性评估表监督每个任务的进度与质量,最大限度地提高每个应用的性能.实验结果表明,A-HRL算法比传统的强化学习算法性能更优. 展开更多
关键词 options 蚁群算法 虚拟机 自适应配置
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ISN预测及其在TCP Reset攻击中的应用
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作者 杨智丹 张松洋 +1 位作者 李丽 汪松鹤 《通信对抗》 2009年第1期41-44,50,共5页
为了增强TCP Reset攻击对目标主机连接的复位能力,研究了操作系统的ISN生成机制。通过对Windows系列4种操作系统进行的序列号采样实验,建立了Windows2000和Windows XP的ISN预测模型。该模型可以逼真地模拟操作系统的ISN生成算法,对IS... 为了增强TCP Reset攻击对目标主机连接的复位能力,研究了操作系统的ISN生成机制。通过对Windows系列4种操作系统进行的序列号采样实验,建立了Windows2000和Windows XP的ISN预测模型。该模型可以逼真地模拟操作系统的ISN生成算法,对ISN近似线性递增分布的目标系统的预测效果与主流预测算法接近,但算法复杂度明显降低。以此模型为基础改进了目前的TCP Reset攻击方法,实验结果表明,攻击程序能够成功复位上述两种操作系统的TCP连接,所需发送RST包的数量较目前的攻击程序大大减小。 展开更多
关键词 FCP reset攻击 初始序列号 线性回归 ISN预测模型
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On the Options of EFL Methodological Approaches
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作者 党金学 《外语教学》 CSSCI 北大核心 1996年第3期58-63,共4页
OntheOptionsofEFLMethodologicalApproaches党金学(西安外国语学院)TakingabouttheapproachestoteachingEnglishasaforeignlang... OntheOptionsofEFLMethodologicalApproaches党金学(西安外国语学院)TakingabouttheapproachestoteachingEnglishasaforeignlanguage(EFL),nearlye... 展开更多
关键词 西安外国语学院 On the options of 金学 EFL Methodological APPROACHES
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连续性RESET/SET对相变存储器疲劳特性的影响 被引量:1
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作者 吴磊 蔡道林 +6 位作者 陈一峰 刘源广 闫帅 李阳 余力 谢礼 宋志棠 《上海交通大学学报》 EI CAS CSCD 北大核心 2021年第9期1134-1141,共8页
为探究连续性RESET操作和连续性SET操作对相变存储器疲劳特性的影响,基于4 Mbit相变存储器芯片进行了不同RESET-SET次数比的疲劳特性研究,给出了连续RESET和连续SET操作后相变单元阻值分布的变化情况.将RESET-only与SET-only模式下的疲... 为探究连续性RESET操作和连续性SET操作对相变存储器疲劳特性的影响,基于4 Mbit相变存储器芯片进行了不同RESET-SET次数比的疲劳特性研究,给出了连续RESET和连续SET操作后相变单元阻值分布的变化情况.将RESET-only与SET-only模式下的疲劳特性与常规疲劳特性进行了对比分析,并对失效原因和修复方法进行了讨论;对比了8种不同RESET-SET次数比下的单元疲劳特性.实验结果表明:连续性RESET操作对相变存储器疲劳特性的影响很小,RESET-only模式下的相变存储器疲劳特性与常规疲劳特性处于同一量级;连续性SET操作会显著降低相变存储器的的疲劳特性,SET-only模式下相变存储器疲劳特性比常规疲劳特性低2个数量级;连续性RESET操作带来的失效无法逆转,而连续性SET操作带来的失效可以通过间隙性施加RESET操作得以修复. 展开更多
关键词 相变存储器 连续性reset操作 连续性SET操作 疲劳特性 失效改善
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Treatment options for alcoholic and non-alcoholic fatty liver disease: A review 被引量:49
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作者 Sukhpreet Singh Natalia A Osna Kusum K Kharbanda 《World Journal of Gastroenterology》 SCIE CAS 2017年第36期6549-6570,共22页
Alcoholic liver disease(ALD)and non-alcoholic fatty liver disease(NAFLD)are serious health problems worldwide.These two diseases have similar pathological spectra,ranging from simple steatosis to hepatitis to cirrhosi... Alcoholic liver disease(ALD)and non-alcoholic fatty liver disease(NAFLD)are serious health problems worldwide.These two diseases have similar pathological spectra,ranging from simple steatosis to hepatitis to cirrhosis and hepatocellular carcinoma.Although most people with excessive alcohol or calorie intake display abnormal fat accumulation in the liver(simple steatosis),a small percentage develops progressive liver disease.Despite extensive research on understanding the pathophysiology of both these diseases there are still no targeted therapies available.The treatment for ALD remains as it was 50 years ago:abstinence,nutritional support and corticosteroids(or pentoxifylline as an alternative if steroids are contraindicated).As for NAFLD,the treatment modality is mainly directed toward weight loss and co-morbidity management.Therefore,new pathophysiology directed therapies are urgently needed.However,the involvement of several inter-related pathways in the pathogenesis of these diseases suggests that a single therapeutic agent is unlikely to be an effective treatment strategy.Hence,a combination therapy towards multiple targets would eventually be required.In this review,we delineate the treatment options in ALD and NAFLD,including various new targeted therapies that are currently under investigation.We hope that soon we will be having an effective multi-therapeutic regimen for each disease. 展开更多
关键词 ALCOHOLIC LIVER DISEASE Non-alcoholic FATTY LIVER DISEASE Treatment options GLUCOCORTICOIDS LIVER transplantation
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