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Adaptively secure ciphertext-policy attribute-based encryption with dynamic policy updating

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Science China(Information Sciences) 2016年第4期59卷 187-202页

作者： Zuobin ying Hui li Jianfeng ma Junwei ZHANG Jiangtao CUI School of Computer Science and Technology Xidian University

Attribute-Based Encryption(ABE) is a promising new cryptographic technique which guarantees fine-grained access control of outsourced encrypted data in the cloud. With the help of ABE, the majority of security issues in accessing cloud data can be solved. However, a key limitation remains, namely policy *** the access policy is updated, a common approach is to have the data owner retrieve the data and reencrypt it with new policy, before sending the new ciphertext back to the cloud. This straight-forward approach will lead to heavy computation and communication overhead. Although a number of other approaches have been proposed in this regard, they suffer from two limitations; namely, supporting only limited update-policy types or having weak security models. In order to address these limitations, we propose a novel solution to the attribute-based encryption access control system by introducing a dynamic policy-updating technique which we call DPU-CP-ABE. The scheme is proved to be adaptively secure under the standard model and can support any type of policy updating. In addition, our scheme can significantly reduce the computation and communication costs of updating ciphertext.

关键词： attribute-based encryption ciphertext-policy dynamic policy updating adaptive secure standard model

Formation process of akaganeite in the simulated wet-dry cycles atmospheric environment

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Journal of materials Science & Technology 2018年第8期34卷 1387-1396页

作者： Haigang Xiao Wei Ye Xiaoping Song Yuantai ma ying li Laboratory for Corrosion and Protection Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China University of ChineseAcademy of Sciences Beijing 100049China Analysis and Testing Department(Testing Center) Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

In order to clarify the formation mechanism and conditions for akaganeite in long-term exposure, the influence of the former corrosion results on akaganeite formation was investigated by simulated experi- ments in laboratory. The combination of XRD, FTIR, SEM and EPma enabled the identification of the rust layer formed on the surface. Accordingly, the nature of the rust layer and the amount of the corrosive species in the rust layer varied with the extension of the exposure. Among them, comparing with the corrosion condition in initial stage, the structure of rust layer after repeated wet-dry cycles was disad- vantage for akaganeite formation. Element CI aggregated at the interface between rust and substrate in the thick part can participate in the formation of akaganeite after the rust layer covered removed. The accumulation effect of salt deposited contributed to akaganeite formation under the condition that salt deposition rate was relatively low.

关键词： Carbon steel Atmospheric corrosion Corrosion products Chloride ions

Review:A survey for image resizing

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第9期15卷 697-716页

作者： Xiao liN ying-lan ma li-zhuang ma Rui-ling ZHANG Department of Computer Science and Engineering Shanghai Jiao Tong University Academy of Information Technology Luoyang Normal University Department of Computer Science College of Engineering University of Illinois at Urbana-Champaign

Image resizing is a key technique for displaying images on different devices, and has attracted much attention in the past few years. This paper reviews the image resizing methods proposed in recent years, gives a detailed comparison on their performance, and reveals the main challenges raised in several important issues such as preserving an important region, minimizing distortions, and improving efficiency. Furthermore, this paper discusses the research trends and points out the possible hotspots in this field. We believe this survey can give some guidance for researchers from relevant research areas, offering them an overall and novel view.

关键词： Image resizing Saliency measures Cropping Seam carving Warping

Synthesis of Al_2O_3-SiC Composite and Its Effect on the Properties of Low-carbon MgO-C Refractories

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Journal of materials Science & Technology 2010年第8期26卷 715-720页

作者： Beiyue ma Qiang Zhu Yong Sun Jingkun Yu ying li School of materials and Metallurgy Northeastern University Shenyang 110004 China Faculty of Engineering University of Wollongong Wollongong NSW 2522 Australia

Al2O3-SiC composite was synthesized with pyrophyllite and natural graphite as raw materials by carbothermal reduction reaction under argon atmosphere. The effect of synthesis temperature on phase composition and microstructure was investigated. Low-carbon MgO-C refractories were prepared by using the synthesized Al2O3-SiC composite as additive. The effect of its addition on the slag penetration and corrosion resistance as well as oxidation resistance of the refractories was investigated, and the slag resistance and oxidation resistance mechanisms of the Al2O3-SiC composite were also discussed. The results show that the synthesis temperature has a great influence on preparation of Al2O3-SiC composite. The Al2O3-SiC composite can be synthesized at 1873-1973 K under argon atmosphere, with pyrophyllite and natural graphite as raw materials, and particle sizes of the composite synthesized at 1973 K are mainly distributed as 1-2 μm. The slag penetration and corrosion resistance of low-carbon M80-C refractories can be remarkably improved by adding the synthesized Al2O3-SiC composite, and the oxidation resistance has an improvement to some extent. The increase of slag viscosity and the formation of MgAl2O4 can effectively inhibit the slag penetration and corrosion for the refractories.

关键词： Oxide-nonoxide composite Carbothermal reduction Penetration Corrosion Oxidation resistance Refractories

Identification and Expression of TOP3αin Gerbera hybrida

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Horticultural Plant Journal 2021年第2期7卷 167-173页

作者： Shenchong li ying Cheng Dan Sun Lulin ma Mingyang li Fan li College of Horticulture and Landscape Architecture Southwest UniversityChongqing 400715China Key Laboratory for Flower Breeding of Yunnan Province National Engineering Research Center for Ornamental HorticultureFloriculture Research InstituteYunnan Academy of Agricultural SciencesKunming 650200China School of Agriculture Yunnan UniversityKunming 650504China

Meiotic recombination and the resulting novel allele combinations are fundamental to plant breeding and the identification of superior ***,the rate of meiotic crossovers is naturally suppressed below its potential ability,which prevents plant breeding *** suppressors of meiotic recombination have been identified in the model plant Arabidopsis and in other crop *** in these genes can lead to increased recombination frequency and could therefore potentially be used to create hyper-recombinant lines for ornamental *** Gerbera hybrida,the anti-crossover factors remain *** this study,we isolated and cloned TOP3αfrom flower buds of ***,and it encoded 935 amino acids with three conserved domains TOPRIM,TOP1Ac and ***,TOP3αwas the highest expressed at the flower bud stage,which coincided with the occurrence of meiotic recombination,suggesting that TOP3αis associated with the regulation of meiotic recombination in ***.

关键词： Gerbera hybrida meiotic recombination TOP3α gene expression ornamental breeding

System Size Resonance Associated with Canard Phenomenon in a Biological Cell System

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Chinese Journal of Chemical Physics 2008年第6期21卷 521-525页

作者： Juan ma Hong-ying li Zhong-huai Hou Hou-wen Xin Department of Chemical Physics University of Science and Technology of China Hefei 230026 China Hefei National Lab of Physical Science at Microscale University of Science and TechnoloEy of China Hefei 230026 China Department of Chemistry Hefei Teachers College Hefei 230000 China

The influence of internal noise on the calcium oscillations is studied. It is found that stochastic calcium oscillations occur when the internal noise is considered, while the corresponding deterministic dynamics only yields a steady state. Also,. the performance of such oscillations shows two maxima with the variation of the system size, indicating the occurrence of system size resonance. This behavior is found to be intimately connected with the canard phenomenon. Interestingly, it is also found that one of the optimal system sizes matches well with the real cell size, and such a match is robust to the variation of the control parameters.

关键词： Internal noise Calcium oscillations System size resonance Canard phenomenon

Surface effect induced phase transformation by Mn removal during annealing and its textures in cold-rolled high manganese transformation-induced plasticity steel

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Journal of Iron and Steel Research International 2022年第3期29卷 494-502页

作者： li-ying liu Ping Yang Dan-dan ma Xin-fu Gu School of materials Science and Engineering University of Science and Technology BeijingBeijing100083China

The surface effect induced transformation texture during vacuum annealing of cold-rolled high manganese transformation-induced plasticity(TRIP)steels was *** to Mn removal occurring at the surface layer,γ→δdiffusional phase transformation leads to the formation of hard pancake-shaped ferrite grains due to solution strengthening at the surface and the centre layer remains as austenite+martensite after *** the case of slow heating,{112}/{111}textures for the surface ferrite were strengthened with the increase in temperature and holding time,indicating an inheritance of rolling *** increasing the heating rate of annealing,the rotated cube texture was developed in surface *** kind of multiphase sandwich structure with hard ferrite surface layer and tough austenite dominant centre can increase tensile strength and should also improve deep drawing properties,therefore providing new possibility of controlling properties for the application of high manganese TRIP steel.

关键词： High manganese transformation-induced plasticity steel Surface effect Texture Microstructure Vacuum annealing

Targeting epigenetic mechanisms in amyloid-β-mediated Alzheimer’s pathophysiology:unveiling therapeutic potential

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Neural Regeneration Research 2025年第1期20卷 54-66页

作者： Jennie Z.li Nagendran Ramalingam Shaomin li Ann Romney Center for Neurologic Diseases Brigham and Women’s Hospital and Harvard Medical SchoolBostonMAUSA

Alzheimer’s disease is a prominent chronic neurodegenerative condition characterized by a gradual decline in memory leading to *** evidence suggests that Alzheimer’s disease is associated with accumulating various amyloid-βoligomers in the brain,influenced by complex genetic and environmental *** memory and cognitive deficits observed during the prodromal and mild cognitive impairment phases of Alzheimer’s disease are believed to primarily result from synaptic *** life,environmental factors can lead to enduring changes in gene expression and the emergence of brain *** changes,known as epigenetic modifications,also play a crucial role in regulating the formation of synapses and their adaptability in response to neuronal *** this context,we highlight recent advances in understanding the roles played by key components of the epigenetic machinery,specifically DNA methylation,histone modification,and microRNAs,in the development of Alzheimer’s disease,synaptic function,and activity-dependent synaptic ***,we explore various strategies,including enriched environments,exposure to non-invasive brain stimulation,and the use of pharmacological agents,aimed at improving synaptic function and enhancing long-term potentiation,a process integral to epigenetic ***,we deliberate on the development of effective epigenetic agents and safe therapeutic approaches for managing Alzheimer’s *** suggest that addressing Alzheimer’s disease may require distinct tailored epigenetic drugs targeting different disease stages or pathways rather than relying on a single drug.

关键词： Alzheimer’s disease DNA methylation enriched environments histone modification microRNAs non-invasive brain stimulation synaptic plasticity

Synthesis and magnetic Properties of a Novel Birnessite Oxide Cs_(0.24)MnO_2

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Chinese Journal of Structural Chemistry 2008年第2期27卷 215-219页

作者： PAN ying-Zhen QIU Xiao-Qing QIHE Ri-ma li li-Ping State Key Laboratory of Structural Chemistry Fujian Institute of Research on theStructure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

The synthesis of a novel birnessite structure manganese oxide, Cs0.24MnO2, via a modified sol-gel route is reported in this work. The product was characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, thermogravimetric analysis （TGA）, and magnetic susceptibility. It is found that Cs0.24MnO2 crystallizes in a monoclinic phase with a nanosheet morphology. With lowering the temperature, Cs0.24MnO2 shows an antiferromagnetic transition at about 43.8 K, which is different from its paramagnetic K-counterpart. The effective moment of Mn ions in Cs0.24MnO2 is determined to be 4.2 μB, indicating a mixed valence of Mng＋/Mn3＋.

关键词： birnessite magnetic antiferromagnetic