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MemSC： A Scan-Resistant and Compact Cache Replacement Framework for Memory-Based Key-Value Cache Systems

Journal of Computer Science & Technology 2017年第1期32卷 55-67页

作者： Mei Li Hong-jun Zhang yan-jun wu Chen Zhao National Engineering Research Center of Fundamental Software Institute of Software Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Computer Science Institute of Software Chinese Academy of Sciences Beijing 100190 China

Memory-based key-value cache systems, such as Memcached and Redis, have become indispensable components of data center infrastructures and have been used to cache performance-critical data to avoid expensive back-end database accesses. As the memory is usually not large enough to hold all the items, cache replacement must be performed to evict some cached items to make room for the newly coming items when there is no free space. Many real-world workloads target small items and have frequent bursts of scans （a scan is a sequence of one-time access requests）. The commonly used LRU policy does not work well under such workloads since LRU needs a large amount of metadata and tends to discard hot items with scans. Small decreases in hit ratio can result in large end-to-end losses in these systems. This paper presents MemSC, which is a scan-resistant and compact cache replacement framework for Memcached. MemSC assigns a multi-granularity reference flag for each item, which requires only a few bits （two bits are enough for general use） per item to support scanresistant cache replacement policies. To evaluate MemSC, we implement three representative cache replacement policies （MemSC-HM, MemSC-LH, and MemSC-LF） on MemSC and test them using various workloads. The experimental results show that MemSC outperforms prior techniques. Compared with the optimized LRU policy in Memcached, MemSC-LH reduces the cache miss ratio and the memory usage of the resulting system by up to 23% and 14% respectively.

关键词： key-value cache system cache replacement scan resistance space efficiency

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A buffer overflow detection and defense method based on RiSC-V instruction set extension

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Cybersecurity 2024年第2期7卷 28-43页

作者： Chang Liu yan-jun wu Jing-Zheng wu Chen Zhao Intelligent Software Research Center Institute of SoftwareChinese Academy of SciencesBejingChina University of Chinese Academy of Sciences BeijingChina State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijingChina

Buffer overflow poses a serious threat to the memory security of modern operating *** overwrites the con-tents of other memory areas by breaking through the buffer capacity limit,destroys the system execution environ-ment,and provides implementation space for various system attacks such as program control flow *** makes it a wide range of harms.A variety of security technologies have been proposed to deal with system security problems including buffer *** example,No eXecute(NX for short)is a memory management technology commonly used in Harvard *** can refuse the execution of code which residing in a specific memory,and can effectively suppress the abnormal impact of buffer overflow on control ***,in recent years,it has also been used in the field of system security,deriving a series of solutions based on NX technology,such as ExecShield,DEP,StackGuard,***,these security solutions often rely too much on the processor archi-tecture so that the protection coverage is insufficient and the accuracy is *** in the emerging system architecture field represented by RiSC-V,there is still a lack of effective solutions for buffer overflow *** the continuous rapid development of the system architecture,it is urgent to develop defense methods that are applicable to different system application environments and oriented to all executable memory spaces to meet the needs of system security ***,we propose BOP,A new system memory security design method based on RISC-V extended instructions,to build a RISC-V buffer overflow detection and defense system and deal with the buffer overflow threat in *** to this method,NX technology can be combined with program control flow analysis,and Nx bit mechanism can be used to manage the executability of memory space,so as to achieve a more granular detection and defense of buffer overflow attacks that may occur in RISC-V system

关键词： RISc-V Operating system security Buffer overflow Control flow hijacking Nx bit Xibop

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Circulating lncRNA MHRT predicts survival of patients with chronic heart failure

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Journal of Geriatric Cardiology 2019年第11期16卷 818-821页

作者： Lie ZHANG yan-jun wu Sui-Long ZHANG Department of Geriatric Cardiovascular Disease the Second Affiliated Hospital of Xi'an Jiaotong UniversityXianChina Department of General Surgery Xi’an Northern HospitalXianChina

Background It has been reported that lncRNA myosin heavy-chain-associated RNA transcripts(MHRT)can inhibit the apoptosis of *** is one of the major pathological changes leading to chronic heart *** The expression level of lncRNA MHRT was assessed by *** values of lncRNA MHRT for chronic heart failure were analyzed by ROC curve *** apoptosis was detected by cell apoptosis *** The results demonstrated that expression of lncRNA MHRT in plasma was down-regulated in patients with chronic heart failure compared to that in healthy ***-regulation of lncRNA MHRT distinguished chronic heart failure from healthy ***-expression of lncRNA MHRT inhibited the apoptosis of human cardiomyocyte cell line AC16 after H2O2 ***-up study showed that chronic heart failure patients with lower expression levels of lncRNA MHRT had worse survival conditions compared to patients with higher expression levels of lncRNA *** We concluded that circulating lncRNA MHRT might serve as a diagnostic and prognostic marker for chronic heart failure treatment.

关键词： Apoptosis Cardiomyocytes Chronic heart failure lncRNA MHRT

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Multiple pathogenic factor-induced complications of cirrhosis in rats: A new model of hepatopulmonary syndrome with intestinal endotoxemia

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World Journal of Gastroenterology 2007年第25期13卷 3500-3507页

作者： Hui-Ying Zhang De-wu Han Zhong-Fu Zhao Ming-She Liu yan-jun wu Xian-Ming Chen Cheng Ji Department of pathophysiology Changzhi Medical CollegeChangzhi 046000 Shanxi Province China Institute of Hepatology Shanxi Medical UniversityTaiyuan 030001 Shanxi Province China Department of Medical Microbiology and Immunology Creighton University School of Medicine Omaha NE 68178 United States Department of Medicine University of Southern California Los Angeles CA 90033 United States

AIM： To develop and characterize a practical model of Hepatopulmonary syndrome. （HPS） in rats.METHODS： The experimental animals were randomized into five feeding groups：（1） control （fed standard diet）, （2） control plus intraperitoneal injection with lipopolysaccharide （LPS）, （3） cirrhosis （fed a diet of maize flour, lard, cholesterol, and alcohol plus subcutaneously injection with carbon tetrachloride （CCI4） oil solution）, （4） cirrhosis plus LPS, and （5） cirrhosis plus glycine and LPS. The blood, liver and lung tissues of rats were sampled for analysis and characterization. Technetium 99m-labeled macroaggregated albumin （Tc99m-MAA） was used to test the dilatation of pulmonary microvasculature.RESULTS： Typical cirrhosis and subsequent hepato- pulmonary syndrome was observed in the cirrhosis groups after an 8 wk feeding period. In rats with cirrhosis, there were a decreased PaO2 and PaCO2 in arterial blood, markedly decreased arterial 02 content, a significantly increased alveolar to arterial oxygen gradient, an increased number of bacterial translocated within mesenteric lymph node, a significant higher level of LPS and tumor necrosis factor-α （TNF-α） in plasma, and a significant greater ratio of Tc99m-MAA brain-overlung radioactivity. After LPS administration in rats with cirrhosis, various pathological parameters got worse and pulmonary edema formed. The predisposition of glycine antagonized the effects of LPS and significantly alleviated various pathological alterations.

关键词： Alcohol Carbon tetrachloride Endotoxin High fat diet

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A Distinctive Pattern for Substituent Effects on Transition Metal Centers:Enhanced Electron-Donating Capacity of Cationic Palladium Species

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CCS Chemistry 2023年第5期5卷 1163-1175页

作者： jun-yan wu Bin-Rui Mo Jin-Dong yang Jin-Pei Cheng Department of Chemistry Tsinghua UniversityBeijing 100084 College of Chemistry Nankai UniversityTianjin 300071 Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192

Electronic and bonding situations at reaction centers are often detected by the remote substituent *** nonorganometallic reactions,this effect is conventionally described by the well-known Hammett-type substituent ***,for most transition metal(TM)-involved systems,no analogous numeral descriptors reflecting the intrinsic differences between metallic and nonmetallic bonding have been rigorously established till ***,we report a Pd(II)–O bond heterolysis energyΔG_(het)(Pd–O)study of the archetypal palladium complexes to represent the thermodynamics of the essential bond-breaking step in Pd-mediated *** we furnish the new substituent constantsσPd^(+)s and therefrom facilitate linear free-energy relationship(LFER)analysis for Pd-catalyzed ***,this led us to find an unexpected electron-donating ability of Pd(II)cation,which provided a gifted experimental support,with the aid of computation,to attribute the frustrating observation of a much scattered curvature in theΔG_(het)(Pd–O)-σ+correlation to the electrondonating capacity of the cationic palladium through back-donation of its *** of LFER analysis withσPd^(+)to predict the redox behavior of the palladium complex and in a kinetics *** study of transmetalation added further credence to their applicability to TM systems.

关键词： bond dissociation energy substituent effects palladium complexes thermodynamics structure–reactivity relationship

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AN ALGORITHM FOR THE SPACECRAFT REENTRY TRAJECTORY

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Chinese Journal of Aeronautics 1993年第3期 164-169页

作者： Gao Reng-qing,Qu Xiang-ju,Xu yan-jun,wu yan-dan (Faculty 509 of Beijing University of Aeronautics and Astronautics, Beijing,China,100083)

This paper presents a method of calculating the flight parameters of spacecraftreentry trajectory. In this method, the variation of spacecraft mass center position and theflight velocity with the altitude is chosen, and then the other flight parameters of reentrytrajectory are calculated. Based on the kinematic and dynamic equations of the mass centerof spacecraft, the formulae used in the method are derived. Using these formulae, an exampleof the flight data of the Columbia shuttle is calculated to verify the validity of themethod. The agreement between the calculated results and the real reentry results is encouragingand shows that the proposed method is an effective and simple one suitable forthe preliminary calculation of reentry trajectory.

关键词： STS AN ALGORITHM FOR THE SPACECRAFT REENTRY TRAJECTORY

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基于异构网络面向多标签系统的推荐模型研究

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软件学报 2017年第10期28卷 2611-2624页

作者：王瑜武延军吴敬征刘晓燕中国科学院软件研究所北京100190 中国科学院大学北京100049

标签成为信息组织的重要方式之一,随着推荐系统的蓬勃发展,标签推荐成为学者们研究的重要问题之一.目前存在各种各样的标签系统,其功能千差万别,标签数据信息越来越复杂.目前研究往往针对特定类型标签数据,缺乏既综合考虑标签数据中不... 详细信息

标签成为信息组织的重要方式之一,随着推荐系统的蓬勃发展,标签推荐成为学者们研究的重要问题之一.目前存在各种各样的标签系统,其功能千差万别,标签数据信息越来越复杂.目前研究往往针对特定类型标签数据,缺乏既综合考虑标签数据中不同类型对象的复杂信息又能适用于多种标签系统数据的标签推荐模型.构建了标签推荐模型Hn MTR,该模型首先针对标签数据中不同类型对象构建异构网络模型,其次对异构网络模型中不同类型顶点进行同空间映射,使不同类型的顶点和边可在同一空间进行量化比较;最后基于同空间映射后网络,引入多参数马尔可夫模型进行标签评分和推荐.通过基于豆瓣、Delicious和Meetup这3个标签系统数据实验,其结果表明,Hn MTR模型平均准确率比目前主流算法提高10%以上,取得了较好的推荐结果.

关键词：异构网络网络嵌入标签推荐标签系统周模型

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Isolation and culture of adult Sertoli cells and their effects on the function of co-cultured allogeneic islets in vitro

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Chinese Medical Journal 2005年第22期118卷 1857-1862页

作者： TENG yan XUE wu-jun DING Xiao-ming FENG Xin-shun XIANG He-li JIANG Ya-zhuo TIAN Pu-xun Department of Kidney Transplantation First Affiliated Hospital of Xi＇an Jiaotong University Xi＇an 710061 China

Background Globally, 180 million people suffer from diabetes mellitus. Islet transplantation is believed to be an almost ideal therapy for insulin-dependent patients. How to maintain the viability and the function of isolated human islets is a challenge in clinical practice. Sertoli cells are considered ＇ nurse cells＇ in the seminiferous tubules and have been used in cell graft protocols for neurodegenerative diseases and diabetes in many studies. Many researchers have used immature murine testes as the primarily source of Sertoli cells in islet transplantation because they are easily purified. Mature human Sertoli cells have been seldom investigated. In the present study, we developed a method for the isolation and culture of Sertoli cells derived from adult human testes, and investigated their effects on the function of allogeneic islets when they were cultured together in vitro. Methods Adult Sertoli cells were prepared successfully by two-step enzyme digestion with trypsin, collagenase and hyaluronidase. They were identified by morphological characteristics and their activity was determined by MTT colorimetry over a 28-day culture time in vitro. A glucose-stimulated insulin secretion test was performed to detect the effects of Sertoli cells on allogeneic islets＇ function when they were co-cultured for 21 days in vitro. Results In cultured cells, mature human Sertoli cells accounted for more than 90% of total cells. The activity of Sertoli cells reached 95 % and they remained highly cytoactive for a long time in vitro （P〉0. 05 ）. Compared with the islets cultured alone, the co-cultured islets with allogeneic Sertoli cells maintained higher sensitivity to glucose stimulation for the duration of the experiment （P〈0.01 ）. Conclusions A method of isolation and culture of Sertoli cells from adult testes has been established. Sertoli cells could enhance allogeneic islets＇ function when they were co-cultured in vitro. They could be a helper cell in islet transplanta

关键词： adult Sertoli cells trophic support allogeneic islet transplantation

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高校数字图书馆元数据检索系统的设计与实现

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计算机工程与设计 2006年第1期27卷 162-164页

作者：严武军马小燕太原师范学院计算机系山西太原030012 山西大学信息管理系山西太原030012

结合承担某高校数字图书馆建设工程项目背景,详细分析了元数据的重要性和都柏林核心数据的特点,提出了高校数字图书馆信息检索系统总的设计思想和统一资源检索模型,最后设计出了数字资源的元数据结构和基于元数据的检索系统。

关键词：数字图书馆元数据都柏林核心数据对象数据检索

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Neuronal regulated cell death in aging-related neurodegenerative diseases:key pathways and therapeutic potentials

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Neural Regeneration Research 2025年第8期20卷 2245-2263页

作者： Run Song Shiyi Yin Jiannan wu junqiang yan Department of Neurology The First Affiliated HospitalCollege of Clinical Medicine of Henan University of Science and TechnologyLuoyangHenan ProvinceChina Neuromolecular Biology Laboratory The First Affiliated HospitalCollege of Clinical Medicine of Henan University of Science and TechnologyLuoyangHenan ProvinceChina

Regulated cell death(such as apoptosis,necroptosis,pyroptosis,autophagy,cuproptosis,ferroptosis,disulfidptosis)involves complex signaling pathways and molecular effectors,and has been proven to be an important regulatory mechanism for regulating neuronal aging and ***,excessive activation of regulated cell death may lead to the progression of aging-related *** review summarizes recent advances in the understanding of seven forms of regulated cell death in age-related ***,the newly identified ferroptosis and cuproptosis have been implicated in the risk of cognitive impairment and neurodegenerative *** forms of cell death exacerbate disease progression by promoting inflammation,oxidative stress,and pathological protein *** review also provides an overview of key signaling pathways and crosstalk mechanisms among these regulated cell death forms,with a focus on ferroptosis,cuproptosis,and *** instance,FDX1 directly induces cuproptosis by regulating copper ion valency and dihydrolipoamide S-acetyltransferase aggregation,while copper mediates glutathione peroxidase 4 degradation,enhancing ferroptosis ***,inhibiting the Xc-transport system to prevent ferroptosis can increase disulfide formation and shift the NADP^(+)/NADPH ratio,transitioning ferroptosis to *** insights help to uncover the potential connections among these novel regulated cell death forms and differentiate them from traditional regulated cell death *** conclusion,identifying key targets and their crosstalk points among various regulated cell death pathways may aid in developing specific biomarkers to reverse the aging clock and treat age-related neurodegenerative conditions.

关键词： apoptosis autophagy cuproptosis disulfidptosis ferroptosis necroptosis neurodegenerative disease neurological aging diseases PANoptosis pyroptosis

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