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Scaling out NUMA-Aware Applications with RDMA-Based Distributed Shared Memory
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作者 Yang Hong Yang Zheng +3 位作者 Fan Yang Bin-Yu Zang Hai-Bing Guan Hai-Bo Chen 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第1期94-112,共19页
The multicore evolution has stimulated renewed interests in scaling up applications on shared-memory multiprocessors,significantly improving the scalability of many applications.But the scalability is limited within a... The multicore evolution has stimulated renewed interests in scaling up applications on shared-memory multiprocessors,significantly improving the scalability of many applications.But the scalability is limited within a single node;therefore programmers still have to redesign applications to scale out over multiple nodes.This paper revisits the design and implementation of distributed shared memory (DSM)as a way to scale out applications optimized for non-uniform memory access (NUMA)architecture over a well-connected cluster.This paper presents MAGI,an efficient DSM system that provides a transparent shared address space with scalable performance on a cluster with fast network interfaces.MAGI is unique in that it presents a NUMA abstraction to fully harness the multicore resources in each node through hierarchical synchronization and memory management.MAGI also exploits the memory access patterns of big-data applications and leverages a set of optimizations for remote direct memory access (RDMA)to reduce the number of page faults and the cost of the coherence protocol.MAGI has been implemented as a user-space library with pthread-compatible interfaces and can run existing multithreaded applications with minimized modifications.We deployed MAGI over an 8-node RDMA-enabled cluster.Experimental evaluation shows that MAGI achieves up to 9.25:4 speedup compared with an unoptimized implementation,leading to a sealable performance for large-scale data-intensive applications. 展开更多
关键词 distributed shared MEMORY (DSM) SCALABILITY multieore evolution NON-UNIFORM MEMORY ACCESS (NUMA) remote direct MEMORY ACCESS (RDMA)
Extending SSD Lifespan with Comprehensive Non-Volatile Memory-Based Write Buffers
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作者 Ziqi Fan Dongchul Park 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第1期113-132,共20页
New non-volatile memory (NVM)technologies are expected to replace main memory DRAM (dynamic random access memory)in the near future.NAND flash technological breakthroughs have enabled wide adoption of solid state driv... New non-volatile memory (NVM)technologies are expected to replace main memory DRAM (dynamic random access memory)in the near future.NAND flash technological breakthroughs have enabled wide adoption of solid state drives (SSDs)in storage systems.However,flash-based SSDs,by nature,cannot avoid low endurance problems because each cell only allows a limited number of erasures.This can give rise to critical SSD reliability issues.Since many SSD write operations eventually cause many SSD erase operations,reducing SSD write traffic plays a crucial role in SSD reliability. This paper proposes two NVM-based buffer cache policies which can work together in different layers to maximally reduce SSD write traffic:a main memory buffer cache design named Hierarchical Adaptive Replacement Cache (H-ARC)and an internal SSD write buffer design named Write Traffic Reduction Buffer (WRB).H-ARC considers four factors (dirty,clean, recency,and frequency)to reduce write traffic and improve cache hit ratios in the host.WRB reduces block erasures and write traffic further inside an SSD by effectively exploiting temporal and spatial localities.These two comprehensive schemes significantly reduce total SSD write traffic at each different layer (i.e.,host and SSD)by up to 3x.Consequently,they help extend SSD lifespan without system performance degradation. 展开更多
关键词 BUFFER cache policy WRITE BUFFER non-volatile MEMORY solid state drive flash MEMORY
寻常型银屑病患者的情绪记忆改变 预览
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作者 于浈 王红梅 《中国疗养医学》 2019年第2期116-118,共3页
目的通过情绪记忆测试对寻常型银屑病患者的情绪记忆功能进行评估,以探讨其情绪记忆的特征。方法使用不同效价的情绪图片学习-再认任务分别对33名寻常型银屑病患者及33名对照进行情绪记忆测试。结果学习阶段,三种情绪图片评分成绩,银屑... 目的通过情绪记忆测试对寻常型银屑病患者的情绪记忆功能进行评估,以探讨其情绪记忆的特征。方法使用不同效价的情绪图片学习-再认任务分别对33名寻常型银屑病患者及33名对照进行情绪记忆测试。结果学习阶段,三种情绪图片评分成绩,银屑病组与对照组比较,差异无统计学意义(均P>0.05)。再认阶段,总情绪图片再认正确得分,银屑病组(39.09±4.48)分与对照组(42.00±3.54)分比较,差异有统计学意义(P<0.05)。进一步分析显示,银屑病组对不同效价情绪图片再认存在分离现象:正性情绪图片再认正确得分,银屑病组(12.33±2.27)分较对照组(13.52±2.06)分明显下降,差异有统计学意义(P<0.05);中性情绪图片再认正确得分,银屑病组(12.82±2.30)分较对照组(13.97±2.13)分明显下降,差异有统计学意义(P<0.05);而在负性情绪图片再认正确得分,银屑病组(13.94±1.80)分与对照组(14.52±1.56)分比较,差异无统计学意义(P>0.05)。结论寻常型银屑病存在情绪记忆的受损,表现为正性、中性情绪记忆损害,而负性情绪记忆相对完整。 展开更多
关键词 寻常型银屑病 情绪 记忆
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A Novel RRAM Based PUF for Anti-Machine Learning Attack and High Reliability
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作者 戴澜 闫强强 +2 位作者 易盛禹 刘文楷 钱鹤 《上海交通大学学报:英文版》 EI 2019年第1期101-106,共6页
Due to the unique response mechanism, physical unclonable function(PUF) has been extensively studied as a hardware security primitive. And compared to other PUFs, the resistive random access memory(RRAM)based PUF has ... Due to the unique response mechanism, physical unclonable function(PUF) has been extensively studied as a hardware security primitive. And compared to other PUFs, the resistive random access memory(RRAM)based PUF has more flexibility with the change of conductive filaments. In this work, we propose an exclusive or(XOR) strong PUF based on the 1 Kbit 1-transistor-1-resistor(1 T1 R) arrays, and unlike the traditional RRAM based strong PUF, the XOR PUF has a stronger anti-machine learning attack ability in our experiments. The reliability of XOR RRAM PUF is determined by the read instability, thermal dependence of RRAM resistance,and aging. We used a split current distribution scheme to make the reliability of XOR PUF significantly improved.After baking for 50 h at a high temperature of 150?C, the intra-chip Hamming distance(Intra-HD) only increased from 0 to 4.5%. The inter-chip Hamming distance(Inter-HD) and uniformity are close to 50%(ideally). And it is proven through the NIST test that XOR PUF has a high uniqueness. 展开更多
关键词 physical unclonable functions resistive random access memory MACHINE LEARNING ATTACK anti-machine LEARNING ATTACK XOR RRAM PUF
情境体验式的乡村景观特征研究 预览
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作者 顾燕燕 郑军德 孙攀 《绿色科技》 2019年第7期191-193,共3页
指出了乡村景观作为乡村建设的重要组成部分,在取得重要成果的同时也存在一些问题。随着人的生活方式及需求转型升级,人们对乡村景观已不仅仅满足于功能及视觉上的需求,更偏向于精神体验和情感回归的情境景观空间。从情境体验角度出发,... 指出了乡村景观作为乡村建设的重要组成部分,在取得重要成果的同时也存在一些问题。随着人的生活方式及需求转型升级,人们对乡村景观已不仅仅满足于功能及视觉上的需求,更偏向于精神体验和情感回归的情境景观空间。从情境体验角度出发,深刻剖析了基于情境体验式景观的作用原理及三重情境体验分析。在此基础上,提出了情境体验式乡村景观主题设定分类及特征表现,以供参考。 展开更多
关键词 情境体验 乡村景观 特征 记忆
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电针联合丰富环境对糖尿病大鼠空间学习记忆能力的影响 预览
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作者 唐明薇 梅希 王风波 《东南国防医药》 2019年第1期17-20,共4页
目的观察电针联合丰富环境对糖尿病大鼠空间学习记忆能力改善的影响作用。方法40只成年Wistar大鼠按随机数字表法分为空白组(n=8)、非干预组(n=8)、电针组(n=8)、丰富环境组(n=8)和电针联合丰富环境组(n=8),除空白组外其他4组大鼠采用... 目的观察电针联合丰富环境对糖尿病大鼠空间学习记忆能力改善的影响作用。方法40只成年Wistar大鼠按随机数字表法分为空白组(n=8)、非干预组(n=8)、电针组(n=8)、丰富环境组(n=8)和电针联合丰富环境组(n=8),除空白组外其他4组大鼠采用链脲佐菌素腹腔注射法制备糖尿病大鼠模型,并于模型制备成功次日开始电针干预及给予多感官刺激的丰富环境,所有大鼠于干预第4周进行Morris水迷宫空间学习记忆能力测验。结果与非干预组[(51.74±0.59)s]比较,电针组、丰富环境组、电针联合丰富环境组逃避潜伏期均显著缩短[(16.26±0.48)s、(15.41±0.87)s、(12.75±0.49)s,P<0.01];电针联合丰富环境组逃避潜伏期较电针组、丰富环境组大鼠缩短更明显(P<0.05)。与非干预组[(2.83±0.27)次]比较,电针组、丰富环境组、电针联合丰富环境组平台穿越次数均明显增加[(5.75±0.66)次、(6.35±0.44)次、(8.73±0.68)次,P<0.01];电针联合丰富环境组穿越次数多于电针组及丰富环境组(P<0.05)。结论电针联合丰富环境能显著改善糖尿病大鼠空间学习记忆能力,且优于单纯电针或丰富环境,提示电针联合丰富环境刺激更有利于糖尿病患者早期认知功能障碍的康复治疗。 展开更多
关键词 电针 丰富环境 糖尿病 学习 记忆
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Postnatal calpeptin treatment causes hippocampal neurodevelopmental defects in neonatal rats 预览
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作者 Zhu-Jin Song San-Juan Yang +2 位作者 Lan Han Bin Wang Guoqi Zhu 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第5期834-840,共7页
Our previous studies showed that the early use of calpain inhibitors reduces calpain activity in multiple brain regions,and that postnatal treatment with calpeptin may lead to cerebellar motor dysfunction.However,it r... Our previous studies showed that the early use of calpain inhibitors reduces calpain activity in multiple brain regions,and that postnatal treatment with calpeptin may lead to cerebellar motor dysfunction.However,it remains unclear whether postnatal calpeptin application affects hippocampus-related behaviors.In this study,Sprague-Dawley rats were purchased from the Animal Center of Anhui Medical University of China.For the experiments in the adult stage,rats were intraperitoneally injected with calpeptin,2 mg/kg,once a day,on postnatal days 7–14.Then on postnatal day 60,the Morris water maze test was used to evaluate spatial learning and memory abilities.The open field test was carried out to assess anxiety-like activities.Phalloidin staining was performed to observe synaptic morphology in the hippocampus.Immunohistochemistry was used to count the number of NeuN-positive cells in the hippocampal CA1 region.DiI was applied to label dendritic spines.Calpeptin administration impaired spatial memory,caused anxiety-like behavior in adulthood,reduced the number and area of apical dendritic spines,and decreased actin polymerization in the hippocampus,but did not affect the number of NeuN-positive cells in the hippocampal CA1 region.For the neonatal experiments,neonatal rats were intraperitoneally injected with calpeptin,2 mg/kg,on postnatal days 7 and 8.Western blot assay was performed to analyze the protein levels of Akt,Erk,p-Akt,p-Erk1/2,Erk1/2,SCOP,PTEN,mTOR,p-mTOR,CREB and p-CREB in the hippocampus.SCOP expression was increased,and the phosphorylation levels of Akt,mTOR and CREB were reduced in the hippocampus.These findings show that calpeptin administration after birth affects synaptic development in neonatal rats by inhibiting the Akt/mTOR signaling pathway,thereby perturbing hippocampal function.Therefore,calpeptin administration after birth is a risk factor for neurodevelopmental defects. 展开更多
关键词 nerve REGENERATION POSTNATAL calpeptin learning and memory HIPPOCAMPUS SPINE development SCOP AKT mTOR neural REGENERATION
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CZ-7, a new derivative of Claulansine F, ameliorates 2V0-induced vascular dementia in rats through a Nrf2-mediated antioxidant responses
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作者 Dan-dan Liu Xia Yuan +14 位作者 Shi-feng Chu Chen Chen Qian Ren Piao Luo Mei-yu Lin Sha-sha Wang Tian-bi Zhu Qi-di Ai Ying-da Zang Dong-ming Zhang Xin He Zhi-hua Huang Hong-shuo Sun Zhong-ping Feng Nai-hong Chen 《中国药理学报:英文版》 SCIE CAS CSCD 2019年第4期425-440,共16页
Vascular dementia (VD) results from accumulated damage in the vascular system, which is characterized by progressive impairments in memory and cognition and is second only to Alzheimer’s disease (AD) in prevalence am... Vascular dementia (VD) results from accumulated damage in the vascular system, which is characterized by progressive impairments in memory and cognition and is second only to Alzheimer’s disease (AD) in prevalence among all types of dementia. In contrast to AD, there is no FDA-approved treatment for VD owing to its multiple etiologies. In this study, we investigated whether CZ-7, a new derivative of Claulansine F (Clau F) with verified neuroprotective activity in vitro, could ameliorate the cognitive impairment of rats with permanent occlusion of bilateral common carotid arteries (2VO) and its potential mechanisms of action. The 2VO rats were orally administered CZ-7 (10, 20, 40?mg/kg) from day 27 to day 53 post-surgery. Morris water maze tests conducted at day 48–51 revealed that CZ-7 administration significantly reduced the escape latency in 2VO rats. After the rats were sacrificed on day 53, morphological studies using Nissl and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining showed that administration of CZ-7 markedly attenuated the pathological changes in CA1–CA3 area of the hippocampus, including neuronal cell loss, nuclear shrinkage, and dark staining of neurons, and significantly decreased the chronic cerebral hypoperfusion-induced cell loss. Klüver–Barrera staining study revealed that CZ-7 administration significantly improved the white matter lesions. 8-OHdG and reactive oxygen species (ROS) immunofluorescent analyses showed that CZ-7 administration significantly decreased oxidative stress in CA1–CA3 area of the hippocampus. Finally, we found that the CZ-7-improved oxidative stress might be mediated via the Nrf2 pathway, evidenced by the double immunofluorescent staining of Nrf2 and the elevation of expression levels of oxidative stress proteins HO-1 and NQO1. In conclusion, CZ-7 has therapeutic potential for VD by alleviating oxidative stress injury through Nrf2-mediated antioxidant responses. 展开更多
关键词 claulansine F CZ-7 vascular DEMENTIA 2VO RATS chronic cerebral HYPOPERFUSION spatial memory oxidative stress Nrf2 HO-1 NQO1
Effect of moxibustion on long-term memory in vascular dementia model rats
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作者 李悦 杨骏 +1 位作者 桂利 樊吟秋 《世界针灸杂志:英文版》 CSCD 2019年第1期63-68,共6页
Objective:To observe the effects on spatial long-term memory in the rats w让h vascular dementia(VD)treated with moxibustion for resolving stasis and promoting meridian circulation.Methods:The modified 2-vascular occlu... Objective:To observe the effects on spatial long-term memory in the rats w让h vascular dementia(VD)treated with moxibustion for resolving stasis and promoting meridian circulation.Methods:The modified 2-vascular occlusion(2-VO)method was used to prepare VD animal model.The rats were randomized into a sham-operation group,a model group,a moxibustion group and a western medication group,15 rats in each one.In the moxibustion group,mild warm moxibustion was applied to"BBihui(百会GV 20)""DazhuT(大椎GV 14)"and"Shentfng(神庭GV 24)",20 min at each point,once a day,for 3 weeks consecutively.In the western medicaion group,mouse nerve growth factor(NGF)was injected intraperitoneally,0.18 mL/kg,once a day,for 3 weeks consecutively.Morris water maze test was used,the time of the first passing platform,the frequency of passing-platform and swimming speed in 120s were determined of the rats in each group.Western blot were used to test the protein expressions of hippocampal Nestin and DCX.Results:At the end of three courses of treatment,compared with sham-operation group,the difference was not significant statistically in swimming speed in the model group,the moxibustion group and the western medication group separately(all P>0.05).Three days after modeling,the mean of escape latency was prolonged obviously in the modeled rats compared with the rats in the shamoperation group(88.84±19.94 vs 18.15±9.41,P<0.01).At the end of three courses of treatment,compared with the sham-operation,group(22.01±10.07),the mean of escape latency was different statistically in the model group(89.18±19.70),the moxibustion group(37.21±13.31)and the western medication group separately(51.50±16.15),all P<0.01.Compared with the model group,the mean of escape latency was shortened in the moxibustion group and western medication group respectively(37.21±13.31 vs 89.18±19.70,51.50±16.15 vs 89.18±19.70,both P<0.01).Compared with the western medication group,there was no statistical significant difference in the mean of escape latency in th 展开更多
关键词 VASCULAR DEMENTIA Water MAZE test MOXIBUSTION LONG TERM memory
High-Throughput Automatic Training System for Spatial Working Memory in Free-Moving Mice
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作者 Shimin Zou Chengyu Tony Li 《神经科学通报:英文版》 SCIE CAS CSCD 2019年第3期389-400,共12页
Effcient behavioral assays are crucial for understanding the neural mechanisms of cognitive functions.Here, we designed a high-throughput automatic training system for spatial cognition(HASS) for free-moving mice.Mice... Effcient behavioral assays are crucial for understanding the neural mechanisms of cognitive functions.Here, we designed a high-throughput automatic training system for spatial cognition(HASS) for free-moving mice.Mice were trained to return to the home arm and remain there during a delay period. Software was designed to enable automatic training in all its phases, including habituation, shaping, and learning. Using this system, we trained mice to successfully perform a spatially delayed nonmatch to sample task, which tested spatial cognition,working memory, and decision making. Performance depended on the delay duration, which is a hallmark of working memory tasks. The HASS enabled a human operator to train more than six mice simultaneously with minimal intervention, therefore greatly enhancing experimental ef?ciency and minimizing stress to the mice.Combined with the optogenetic method and neurophysiological techniques, the HASS will be useful in deciphering the neural circuitry underlying spatial cognition. 展开更多
关键词 COGNITIVE functions AUTOMATIC training Free-moving MICE Working memory Spatial COGNITION
Memway: In-Memory Waylaying Acceleration for Practical Rowhammer Attacks Against Binaries
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作者 Lai Xu Rongwei Yu +1 位作者 Lina Wang Weijie Liu 《清华大学学报自然科学版(英文版)》 EI CAS CSCD 2019年第5期535-545,共11页
The Rowhammer bug is a novel micro-architectural security threat, enabling powerful privilege-escalation attacks on various mainstream platforms. It works by actively flipping bits in Dynamic Random Access Memory(DRAM... The Rowhammer bug is a novel micro-architectural security threat, enabling powerful privilege-escalation attacks on various mainstream platforms. It works by actively flipping bits in Dynamic Random Access Memory(DRAM) cells with unprivileged instructions. In order to set up Rowhammer against binaries in the Linux page cache, the Waylaying algorithm has previously been proposed. The Waylaying method stealthily relocates binaries onto exploitable physical addresses without exhausting system memory. However, the proof-of-concept Waylaying algorithm can be easily detected during page cache eviction because of its high disk I/O overhead and long running time. This paper proposes the more advanced Memway algorithm, which improves on Waylaying in terms of both I/O overhead and speed. Running time and disk I/O overhead are reduced by 90% by utilizing Linux tmpfs and inmemory swapping to manage eviction files. Furthermore, by combining Memway with the unprivileged posix fadvise API, the binary relocation step is made 100 times faster. Equipped with our Memway+fadvise relocation scheme,we demonstrate practical Rowhammer attacks that take only 15–200 minutes to covertly relocate a victim binary,and less than 3 seconds to flip the target instruction bit. 展开更多
关键词 Rowhammer bug Waylaying algorithm in-memory SWAPPING page cache eviction
A Deep Learning Method for Chinese Singer Identification
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作者 Zebang Shen Binbin Yong +2 位作者 Gaofeng Zhang Rui Zhou Qingguo Zhou 《清华大学学报自然科学版(英文版)》 EI CAS CSCD 2019年第4期371-378,共8页
As a subfield of Multimedia Information Retrieval(MIR), Singer IDentification(SID) is still in the research phase. On one hand, SID cannot easily achieve high accuracy because the singing voice is difficult to model a... As a subfield of Multimedia Information Retrieval(MIR), Singer IDentification(SID) is still in the research phase. On one hand, SID cannot easily achieve high accuracy because the singing voice is difficult to model and always disturbed by the background instrumental music. On the other hand, the performance of conventional machine learning methods is limited by the scale of the training dataset. This study proposes a new deep learning approach based on Long Short-Term Memory(LSTM) and Mel-Frequency Cepstral Coefficient(MFCC) features to identify the singer of a song in large datasets. The results of this study indicate that LSTM can be used to build a representation of the relationships between different MFCC frames. The experimental results show that the proposed method achieves better accuracy for Chinese SID in the MIR-1 K dataset than the traditional approaches. 展开更多
关键词 SINGER IDENTIFICATION TIMBRE modeling DEEP learning LONG SHORT-TERM memory
Leakage Is Prohibited: Memory Protection Extensions Protected Address Space Randomization
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作者 Fei Yan Kai Wang 《清华大学学报自然科学版(英文版)》 EI CAS CSCD 2019年第5期546-556,共11页
Code reuse attacks pose a severe threat to modern applications. These attacks reuse existing code segments of vulnerable applications as attack payloads and hijack the control flow of a victim application. With high c... Code reuse attacks pose a severe threat to modern applications. These attacks reuse existing code segments of vulnerable applications as attack payloads and hijack the control flow of a victim application. With high code entropy and a relatively low performance overhead, Address Space Layout Randomization(ASLR) has become the most widely explored defense against code reuse attacks. However, a single memory disclosure vulnerability is able to compromise this defense. In this paper, we present Memory Protection Extensions(MPX)-assisted Address Space Layout Randomization(M-ASLR), a novel code-space randomization scheme. M-ASLR uses several characteristics of Intel MPX to restrict code pointers in memory. We have developed a fully functioning prototype of M-ALSR, and our evaluation results show that M-ASLR:(1) offers no interference with normal operation;(2) protects against buffer overflow attacks, code reuse attacks, and other sophisticated modern attacks;and(3) adds a very low performance overhead(3.3%) to C/C++ applications. 展开更多
关键词 ADDRESS SPACE Layout RANDOMIZATION (ASLR) Intel Memory Protection EXTENSIONS (MPX) code REUSE attack
Biomimetic Janus Paper with Controllable Swelling for Shape Memory and Energy Conversion
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作者 Pan Tian Zhiguang Guo 《仿生工程学报:英文版》 SCIE EI CSCD 2019年第1期1-12,共12页
Being inspired by the "seismonastic reaction"of Mimosa pudica,an asymmetric swelling system was constructed to induce the controllable directional deformation of filter paper.In this work,multifunctional bio... Being inspired by the "seismonastic reaction"of Mimosa pudica,an asymmetric swelling system was constructed to induce the controllable directional deformation of filter paper.In this work,multifunctional biomimetic Janus paper was facilely fabricated via depositing poly(vinylidene fluoride)(PVDF)on one side of Qualitative Filter Paper (QFP),the permeation of polymer solutions within filter paper was well controlled during fabrication.The wetting and swelling behavior of the prepared Janus paper were detected.The Janus paper showed controllable swelling-induced deformations in water.Both the degree and orientation of the deformation were fully investigated.On the one hand,the degree of deformation depends on the gradient wettability and hygroscopicity of the Janus paper,on the other hand,the orientation of deformation is related to the storage and release of stress.Additionally,the steady deformation during swelling endows the Janus paper with novel shape memory property both under idling and loading conditions.The Janus paper was also applied to achieve reversible energy conversion from the swelling potential energy to mechanical potential energy. 展开更多
关键词 JANUS PAPER SWELLING shape MEMORY energy CONVERSION
Neuroprotective effect of Sanqi Tongshuan Tablets on sequelae post-stroke in rats
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作者 Wei-ting Wang Chun-hua Hao +6 位作者 Shao-xiang Zhang Xiang-hua Zhang Feng Guo Shuang-yong Sun Rui Zhang Zhuan-you Zhao Li-da Tang 《中草药:英文版》 CAS 2019年第1期45-51,共7页
Objective: To identify the therapeutic effect and possible mechanisms of Chinese medicine Sanqi Tongshuan Tablets(SQTS) on sequelae post-stroke in rats.Methods: The rat cerebral ischemia sequelae post-stroke models we... Objective: To identify the therapeutic effect and possible mechanisms of Chinese medicine Sanqi Tongshuan Tablets(SQTS) on sequelae post-stroke in rats.Methods: The rat cerebral ischemia sequelae post-stroke models were successfully induced by blocking the middle cerebral artery with electric coagulator after the seventh week and balance beam test ≤ 4. The rats were then received with SQTS(0.5, 1, and 2 g/kg) and Naodesheng(NDS, 1.24 g/kg), Vinpocetine(VP,1.55 mg/kg) for 30 d. The beam-walking test and shuttle test were performed before and after 10, 20, and 30 d of administration. In addition, histopathology changes and GAP-43, GFAP were measured by H&E staining and immunohistochemisty.Results: The model displayed signs of brain damage on motor function, learning and memory function and histopathology. After 30 d of treatment, SQTS at different doses(0.5, 1.0, and 2.0 g/kg) restored the beam-walking scores by 21.7%(P > 0.05), 30.4%(P > 0.05), and 39.1%(P < 0.05);Decreased electric shock by 35.0%(P > 0.05), 50.0%(P > 0.05), and 75.0%(P < 0.05), respectively. On the other hand, the histological changes were less severe and the GAP-43 expression increased in hippocampal CA1 and cortical region.Conclusion: SQTS showed therapeutic benefits on sequelae post-stroke in rats, which might be through the pathway of regeneration or neuroplasticity. 展开更多
关键词 learning and MEMORY MOTOR function RATS Sanqi Tongshuan TABLETS SEQUELAE post-strokes
Negative Differential Resistance and Rectifying Effects of Diblock Co-Oligomer Molecule Devices Sandwiched between C2N-h2D Electrodes
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作者 叶萌 夏蔡娟 +1 位作者 张博群 马越 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第4期75-78,共4页
Based on nonequilibrium Green’s function method in combination with density functional theory, we study the electronic transport properties of dipyrimidinyl-diphenyl molecules embedded in a carbon atomic chain sandwi... Based on nonequilibrium Green’s function method in combination with density functional theory, we study the electronic transport properties of dipyrimidinyl-diphenyl molecules embedded in a carbon atomic chain sandwiched between zigzag graphene nanoribbon and different edge geometries C2N-h2D electrodes. Compared with the graphene electrodes, the C2N-h2D electrode can cause rectifying and negative differential resistance effects.For C2N-h2D with zigzag edges, a more remarkable negative differential resistance phenomenon appears, whereas armchair-edged C2N-h2D can give rise to much better rectifying behavior. These results suggest that this system can be potentially useful for designs of logic and memory devices. 展开更多
关键词 NONEQUILIBRIUM system MEMORY
Considerations on the Relationship Between Violence, Social Fear, and Urban Transformations 预览
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作者 Joao Vitor Schmutzler Abrahao Francisco Ramos de Farias Lobélia da Silva Faceira 《美中教育评论:B》 2019年第1期34-40,共7页
The purpose of this paper is to reflect on violence, social fear, and urban transformations in order to elicit some discussions about the relationship between these phenomena and their possible repercussions in the li... The purpose of this paper is to reflect on violence, social fear, and urban transformations in order to elicit some discussions about the relationship between these phenomena and their possible repercussions in the life of the social actors that inhabit the cities. In this way, we intend to initiate our reflection by deconstructing the binary character of violence in relation to the conceptual framework already known, proposing an approach to its characteristic, that is, to conceive it as a movement. We also intend to explain the feeling of fear as a mechanism of survival, its social particularity of orchestration and its implications in the lives of the urban social actors. Furthermore, we aim at explaining the urban transformations that are closely linked to the metropolises, highlighting their peculiarities and their consequences in order to emphasize the impacts on their inhabitants. In this way, we intend to conclude this study with some considerations regarding the interactions between these three phenomena that are strongly interrelated with life in the great metropolises. 展开更多
关键词 VIOLENCE SOCIAL FEAR SOCIAL MEMORY CITY
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无法满足的欲望——《远山淡影》中悦子形象再认识 预览
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作者 董慧 《阴山学刊:社会科学版》 2019年第1期39-44,共6页
《远山淡影》是石黑一雄第一部作品,作者采用双线叙事手法,以记忆为轴线将主人公悦子的故事以第一人称叙事视角的方式呈现给读者。在回忆过去时,悦子扭曲自己的记忆。扭曲的记忆背后是个人尊严的保全,更是无法言说的欲望。聚焦悦子对爱... 《远山淡影》是石黑一雄第一部作品,作者采用双线叙事手法,以记忆为轴线将主人公悦子的故事以第一人称叙事视角的方式呈现给读者。在回忆过去时,悦子扭曲自己的记忆。扭曲的记忆背后是个人尊严的保全,更是无法言说的欲望。聚焦悦子对爱和自由的欲望,分析悦子与欲望代替品公公绪方先生和两任丈夫间的关系以及欲望产生的深层次原因——战争创伤和日本战后新的社会价值的影响,而这一点是学界长期忽略的。由于欲望是无法满足的,悦子只能不断游走在代替品间,最终孤独地度过余生。 展开更多
关键词 《远山淡影》 记忆 欲望 代替品
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Improvement Design for Distributed Real-Time Stream Processing Systems 预览
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作者 Wei Jiang Liu-Gen Xu +1 位作者 Hai-Bo Hu Yue Ma 《电子科技学刊:英文版》 CAS CSCD 2019年第1期3-12,共10页
In the era of Big Data,typical architecture of distributed real-time stream processing systems is the combination of Flume,Kafka,and Storm.As a kind of distributed message system,Kafka has the characteristics of horiz... In the era of Big Data,typical architecture of distributed real-time stream processing systems is the combination of Flume,Kafka,and Storm.As a kind of distributed message system,Kafka has the characteristics of horizontal scalability and high throughput,which is manly deployed in many areas in order to address the problem of speed mismatch between message producers and consumers.When using Kafka,we need to quickly receive data sent by producers.In addition,we need to send data to consumers quickly.Therefore,the performance of Kafka is of critical importance to the performance of the whole stream processing system.In this paper,we propose the improved design of real-time stream processing systems,and focus on improving the Kafka's data loading process.We use Kafka cat to transfer data from the source to Kafka topic directly,which can reduce the network transmission.We also utilize the memory file system to accelerate the process of data loading,which can address the bottleneck and performance problems caused by disk I/O.Extensive experiments are conducted to evaluate the performance,which show the superiority of our improved design. 展开更多
关键词 Kafka Kafka cat memory file SYSTEM MESSAGE QUEUE real-time STREAM processing SYSTEM
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Shape memory effect of dual-phase NiMnGaTb ferromagnetic shape memory alloys
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作者 Jiang Zhang Yong-hong Ma +1 位作者 Ruo-lin Wu Jing-min Wang 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2019年第3期321-328,共8页
The evolution of microstructure,reverse martensitic transformation and the conelated influence on shape memory effect was investigated in as-cast and directionally solidified dual-phase NiMnGaTb alloys.The directional... The evolution of microstructure,reverse martensitic transformation and the conelated influence on shape memory effect was investigated in as-cast and directionally solidified dual-phase NiMnGaTb alloys.The directionally solidified alloys exhibit single-crystal microstructure,preferred dendrite microstructure,and mussy dendrite microstructure in the specimens grown at a withdrawal rate(v)of 10,50 and 200,and 1000μm/s,respectively.The precipitates dispersively distribute in the martensite matrix for the directionally solidified alloys.With the refined grains and particle precipitates,the reverse martensitic transformation gradually shifts to lower temperatures and the temperature span is significantly broadened.The directional solidification technology can effectively enhance the strains recovered due to shape memory effect C;sme)and decrease the compressive stress required to trigger the reorientation of twins(δ)via the realization of preferred orientation,while the maximalεsme and minimumδcan reach 4.96%and 14 MPa in v=10μm/s specimens,respectively.The formation of dendrite morphology degrades the shape memory strain,andεsme decreases with the growth of secondary dendritic arms. 展开更多
关键词 NiMnGaTb ALLOY Directional SOLIDIFICATION DUAL-PHASE MICROSTRUCTURE SHAPE MEMORY effect
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