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The quantum cocktail party problem

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Science China(Physics,Mechanics & Astronomy) 2020年第5期63卷 2-5页

作者： xiao liang YaDong Wu Hui Zhai Institute for Advanced Study Tsinghua UniversityBeijing 100084China Laboratory of Quantum Information University of Science and Technology of ChinoHefei 230026China

The cocktail party problem refers to the phenomenon that the brain of a listener can focus on a single voice while filtering out a range of other voices in a multi-talker situation,say,in a cocktail party[1].This selective attention problem was firstly defined as the"cocktail party problem"(CPP)by Cherry[2]in *** recent years,machine-learning based approaches to solve the CPP were essential for many industrial applications such as automated speech *** independent component analysis(ICA)is such an algorithm particularly suitable for the *** CPP also has applications in physical science such as astrophysics data analysis[3,4].

关键词： quantum problem filtering

Reinforcement Learning-Based Sensitive Semantic Location Privacy Protection for VANETs

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China Communications 2021年第6期18卷 244-260页

作者： Minghui Min Weihang Wang liang xiao Yilin xiao Zhu Han Department of Information and Communication Engineering Xiamen UniversityXiamen 361005China School of Information and Control Engineering ChinaUniversity of Mining and TechnologyXuzhou 221116China The Affiliated Hospital of China University of Mining and Technology Xuzhou 221116China Department of Electrical and Computer Engineering University of HoustonHouston TX 77004USA Beijing Key Laboratory of Mobile Computing and Pervasive Device No.6 Kexueyuan South RoadBeijing 100190China

Location-based services(LBS)in vehicular ad hoc networks(VANETs)must protect users’privacy and address the threat of the exposure of sensitive locations during LBS *** release not only their geographical but also semantic information of the visited places(e.g.,hospital).This sensitive information enables the inference attacker to exploit the users’preferences and life *** this paper we propose a reinforcement learning(RL)based sensitive semantic location privacy protection *** scheme uses the idea of differential privacy to randomize the released vehicle locations and adaptively selects the perturbation policy based on the sensitivity of the semantic location and the attack *** scheme enables a vehicle to optimize the perturbation policy in terms of the privacy and the quality of service(QoS)loss without being aware of the current inference attack model in a dynamic privacy protection *** solve the location protection problem with high-dimensional and continuous-valued perturbation policy variables,a deep deterministic policy gradientbased semantic location perturbation scheme(DSLP)is *** actor part is used to generate continuous privacy budget and perturbation angle,and the critic part is used to estimate the performance of the *** demonstrate the DSLP-based scheme outperforms the benchmark schemes,which increases the privacy,reduces the QoS loss,and increases the utility of the vehicle.

关键词： semantic location sensitivity locationbased services VANET differential privacy reinforcement learning

A Facile Route to Unsymmetrical Sulfide

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Chinese Chemical Letters 2003年第3期14卷 235-238页

作者： Ying Hong ZHU Ping LU Hui lou xiao Ming ZHENG Department of Chemistry Zhejiang University at Xi Xi campusHangzhou 310028

Unsymmetrical sulfides can be generated by the reaction of chlorine substituted aromatic compounds in sulfoxide in the presence of fluorine anion in fair yield. A likely mechanism was proposed.

关键词： Unsymmetrical sulfide aromatic nucleophilic substitution.

Reaction site and mechanism in the UV or visible light induced TiO2 photodegradation of Orange G

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Journal of Environmental Sciences 2006年第1期18卷 180-183页

作者： YANG Shi-ying lou Li-ping WU xiao-na CHEN Ying-xu Department of Environmental Engineering Zhejiang University Hangzhou 310029 China College of Environmental Science and Engineering Ocean University of China Qingdao 266003 China

For TiO2 heterogeneous reaction, the reaction site and the detailed mechanism are interesting and controversy topics. In this paper, effects of surface fluorination of TiO2 on the photocatalytic degradation of an azo dye, Orange G（OG） under UV or visible light irradiation were investigated, and the possible reaction site and mechanism were elucidated. The adsorption of OG on TiO2 was nearly inhibited by fluoride but its UV light induced photodegradation rate was greatly increased by a factor of about 2.7, which was due to the more generated free hydroxyl radicals. It supported the views that fluoride could desorb the oxidant species from surface and that the reaction sites could move to the bulk solution. In TiO2/Vis system, the observed inhibition effects of fluorination could be interpreted by the competitive adsorption, which provided additional evidences that the visible light sensitized photodegradation of dye pollutants on the catalyst surface.

关键词： photocatalytic degradation mechanism adsorption fluorination dye pollutants

Involvement of chloride anion in photocatalytic process

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Journal of Environmental Sciences 2005年第5期17卷 761-765页

作者： YANG Shi-ying CHEN Ying-xu lou Li-ping WU xiao-na Department of Environmental Engineering Zhejiang University Hangzhou 310029 China College of Environmental Sciences anti Engineering Ocean University of China Qingdao 266003 China

The effect of Cl^- on photocatalytic degradation（PCD） of pollutants is an important factor since it is ubiquitous in nature. In general, Cl^- showed an inhibition on photodegradation due to its scavenging HO- radicals. In this paper, experiments were carried out to examine the effects of CI on the PCD of Methylene Blue （MB） and Orange II （OII） in aqueous TiO2 suspensions under UV light illumination. It was found that low concentration of Cl^- （〈 0.01 mol/L） showed little influence on both dyes, however, high concentration of Cl^- （〉 0.10 mol/L） had a very different influence on the decolorization of dyes： a significant inhibition for MB but a great promotion for Oll. In the presence of 0.50 mol/L Cl^- , the rate decreased by 70% for MB while increased 7.5-fold for Oll. Furthermore, two bands in the ultraviolet region of Oll were rapidly broken down. The proposed mechanism was discussed in detail.

关键词： photocatalytic degradation TiO2 dye pollutants chloride ion mechanism

Expression and correlation of CD44v6, vascular endothelial growth factor, matrix metalloproteinase-2, and matrix metalloproteinase-9 in Krukenberg tumor

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World Journal of Gastroenterology 2005年第32期11卷 5032-5036页

作者： Ge lou Ying Gao xiao-Ming Ning Qi-Fan Zhang Tumor Hospital of Harbin Medical University Harbin 150040 Heilongjiang Province China

AIM： To explore the expression and correlation of CD44v6, vascular endothelial growth factor （VEGF）, matrix metalloproteinase （MMP）-2 and matrix metalloproteinase （MMP）-9 in Krukenberg and primary epithelial ovarian carcinoma. METHODS： The expressions of CD44v6, VEGF, MMP-2 and MMP-9 were detected by immunohistochemical method in 20 cases of normal ovarian tissues, 38 cases of Krukenberg tumor and 45 cases of primary epithelial ovarian carcinoma. RESULTS： The expression of CD44v6 （primary epithelial ovarian carcinoma tissue vs normal ovarian tissue： χ^2= 4.516, P= 0.034; Krukenberg tumor tissue vsnormal ovarian tissue： χ^2 = 19.537, P = 0.001） and VEGF （primary epithelial ovarian carcinoma tissue vs normal ovarian tissue： P = 0.026; Krukenberg tumor tissue vs normal ovarian tissue： χ^2 = 22.895, P = 0.001） was significantly higher in primary epithelial ovarian carcinoma tissue and Krukenberg tumor tissue than in normal ovarian tissue. The positive expression rate of MMP-2 and MMP-9 was 0% in the normal ovarian tissue. The positive expression rate of CD44v6 （ χ^2= 10.398, P= 0.001）, VEGF （ χ^2= 13.149, P = 0.001）, MMP-2 （ χ^2 = 33.668, P = 0.001） and MMP-9 （ χ^2= 38.839, P = 0.001） was remarkably higher in Krukenberg tumor than in primary epithelial ovarian carcinoma. The correlation of CD44v6, VEGF, MMP-2, and MMP-9 was observed in primary epithelial ovarian carcinoma and Krukenberg tumor. CONCLUSION： CD44v6, VEGF, MMP-2, and MMP-9 are involved in ovarian carcinoma, gastric cancer and Krukenberg tumor. Detection of CD44v6, VEGF, MMP-2 and MMP-9 may contribute to the diagnosis of ovarian carcinoma, gastric cancer, and Krukenberg tumor.

关键词： CD44v6 VEGF, MMPs Krukenberg tumor

Effects of Hirudin on High Glucose-Induced Oxidative Stress and Inflammatory Pathway in Rat Dorsal Root Ganglion Neurons

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Chinese Journal of Integrative Medicine 2020年第3期26卷 197-204页

作者： LIU Wei liang xiao-chun SHI Yue Department of Traditional Chinese Medicine Peking Union Medical College Hospital Peking Union Medical College Chinese Academy of Medical Sciences

Objective:To investigate protective effects of hirudin on oxidative stress and apoptosis of spinal dorsal root ganglion cells in high-glucose rats at the cellular and molecular ***:Dorsal root ganglion neurons(DRGn)were harvested from embryonic day in 15 SD rats,purified and identificated after primary *** were divided into the normal control group,high-glucose(HG)group,positive control(alpha-lipoic acid,ALA)group,low-dose hirudin group(H1),medium-dose hirudin group(H2)and high-dose hirudin group(H3).The control group was cultured by neuron specific culture medium,while the HG group was cultured by neuron specific culture medium and 20 mmol/L glucose(HG medium).The hirudin groups were cultured by HG medium+0.25 IU/mL hirudin(H1),HG medium+0.5 IU/mL hirudin(H2)and HG medium+1 IU/mL hirudin(H3).The ALA group was cultured by HG medium +100μmol/L ALA.3-(4,5-dimethylthiazol-2-yl)-2,5-diphenylt etrazolium bromide(MTT)assay was used to explore the optimum concentration and intervention *** cytometry assay was used to detect the level of reactive oxygen series(ROS).Western blot and quantificational realtime polymerase chain reaction(qRT-PCR)were used to detect the expression of protein and mRNA of nuclear factor erythroid 2-related factor 2(Nrf-2),hemeoxygence-1(HO-1),nuclear factor-κB(NF-κB)and *** assay was used to test the apoptosis rate of different ***:After 24 h of culture,the cell activity of hirudin and ALA groups were higher than that of HG group,and there was a statistical difference between the H1 group and HG group(P<0.05).In hirudin groups,the apoptosis rate of cells,the expression of activated Caspase-3 protein and Caspase-3 mRNA were lower than those of HG group(P<0.01),higher than those of ALA group(P<0.01 or P<0.05).The ROS level of hirudin groups was higher than that of ALA group(P<0.01),lower than that of HG group(P<0.01 or P<0.05).The expression of NF-κB(P65)protein in H3 group were lower than those of HG g

关键词： hirudin diabetic peripheral neuropathy oxidative stress apoptosis dorsal root ganglion neuron

The Unconventional Influence of a Nearby Molecule onto Transport of Single C60 Molecule Transistor

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Chinese Physics Letters 2019年第12期36卷 62-66页

作者： xiao Guo Wen-jie liang Beijing National Center for Condensed Matter Physics Bejjing Key Laboratory for Nanomaterials and NanodevicesInstitute of PhysicsChinese Academy of SciencesBeijing 100190 CAS Center of Excellence in Topological Quantum Computation and School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190 Songshan Lake Materials Laboratory Dongguan 523808

We study the transport property of single C60 molecular transistors with special focus on the situation that other molecules are in *** devices are prepared using electromigration and thermal deposition *** single C60 molecule transistors show typical coulomb blockade behavior at low *** we increase the coverage of molecules slightly by extending the deposition time,the transport spectrum of devices displays a switching behavior in the general coulomb blockade *** attribute this unconventional phenomenon to the influence from a nearby C60 *** analyzing this transport behavior quantitatively based on the parallel-double-quantum-dot model,the interaction from the nearby molecule is proved to be of capacity and tunneling *** stimulation is also applied to the device to investigate the effect of local charging environment variation on intermolecular interaction.

关键词： transport behavior tunneling

Quantum Binary Symmetric Channels

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Chinese Physics Letters 2001年第6期18卷 721-723页

作者： CHEN xiao-Yu QIU Pei-liang Division of Physics China Institute of MetrologyHangzhou 310034 Department of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 310027

Quantum binary symmetric channels are defined via the invariance of fidelity under unitary transformations of the input density operators. In this definition, they not only include the most studied case of the depolarizing channel but also other channels. We investigate the character of the latter and find the maximum of the coherent information to estimate the capacities of the channels.

关键词： operators. latter unitary