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Synthesis of High Molecular Weight Polyethylene and E-MA Copolymers Using Iminopyridine Ni(Ⅱ) and Pd(Ⅱ) Complexes Containing a Flexible Backbone and Rigid Axial Substituents

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Chinese Journal of Polymer Science 2023年第2期41卷 233-239页

作者： Yu-dan liao Qi Cai Sheng-Yu Dai School of Chemical and Environmental Engineering Anhui Polytechnic UniversityWuhu241000China Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei230601China

Suppressing the chain transfer reactions during polymerization in late-transition metal-catalyzed olefin polymerization systems is the key to obtaining high molecular weight polyolefin materials. In this work, two efficient strategies(“sandwich” and rotation-restricted strategies)to retard chain transfer reactions in ethylene(co)polymerization were employed for the iminopyridyl system. Herein, a family of iminopyridyl Ni(Ⅱ)and Pd(Ⅱ) complexes with a flexible backbone and rigid axial bulky aryl substituents were designed, synthesized and characterized. In ethylene polymerization, the iminopyridyl Ni(Ⅱ) and Pd(Ⅱ) catalysts using the two strategies exhibited reasonable activities and generated highly branched polyethylenes with high molecular weights, where catalysts with dibenzosuberyl substituents exhibited significantly higher activities and produced higher molecular weight polyethylene than catalysts with 8-arylnaphthalenyl substituent. A similar trend of activities and molecular weights was also found in the copolymerization of ethylene with MA using the Pd(Ⅱ) catalysts. Moreover, highly branched E-MA copolymers with moderate to high molecular weights and high incorporation ratios(up to 17.4 mol%) were generated with the two Pd(Ⅱ) catalysts. Most interestingly, as compared with the dibenzhydryl Ni(Ⅱ) and Pd(Ⅱ) catalysts, the catalysts using the two strategies exhibited a superior ability to retard the chain transfer reactions and generated polymers and copolymers with 1-2 orders of magnitude higher molecular weights during ethylene(co)polymerization.

关键词： Ni(Ⅱ)and Pd(Ⅱ) Suppressing chain transfer High molecular weight Ethylene(co)polymerization

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Content-adaptive robust error concealment for packet-lossy H.264 video streaming

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第z1期7卷 41-47页

作者： liao Ning YAN dan QUAN Zi-yi MEN Ai-dong Multimedia Center School of Telecommunication Engineering Beijing University of Posts & Telecom Beijing 100876 China Multimedia Center School of Telecommunication Engineering Beijing University of Posts & Telecom Beijing 100876 China Multimedia Center School of Telecommunication Engineering Beijing University of Posts & Telecom Beijing 100876 China Multimedia Center School of Telecommunication Engineering Beijing University of Posts & Telecom Beijing 100876 China

In this paper, we present a spatio-temporal post-processing error concealment (EC) algorithm designed initially for a H.264 video-streaming scheme over packet-lossy networks. It aims at optimizing the subjective quality of the restored video under the constraints of low delay and computational complexity, which are critical to real-time applications and portable devices having limited resources. Specifically, it takes into consideration the physical property of motion field in order to achieve more meaningful perceptual video quality, in addition to the improved objective PSNR. Further, a simple bilinear spatial interpolation approach is combined with the improved boundary-match (B-M) based temporal EC approach according to texture and motion activity analysis. Finally, we propose a low complexity temporal EC method based on motion vector interpolation as a replacement of the B-M based approach in the scheme under low-computation requirement, or as a complement to further improve the scheme's performance in applications having enough computation resources. Extensive experiments demonstrated that the proposal features not only better reconstruction, objectively and subjectively, than JM benchmark, but also robustness to different video sequences.

关键词： Error concealment, Error control, H.264/AVC, Video streaming, Lossy transmission

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Robust spatio-temporal error concealment for packet- lossy H.264 video transmission

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The Journal of China Universities of Posts and Telecommunications 2006年第3期13卷 87-92页

作者： liao Ning YAN dan QUAN Zi-yi MEN Ai-dong Multimedia Center Beijing University of Posts and TelecommunicationsBeijing 100876 China

In this article, a spatio-temporal post-processing error concealment algorithm designed initially for a H.264 video-streaming scheme over packet-lossy networks has been presented. It aims at optimizing subjective quality of restored video and the conventional objective metric, peak signal-to-noise ratio （PSNR）, as well, under the constraints of low delay and computational complexity, which are critical to real-time applications and portable devices having limited resources. Specifically, it takes into consideration physical property of motion to achieve more meaningful perceptual video quality. Further, a content-adaptive bilinear spatial interpolation approach and a temporal error concealment approach are combined under a unified boundary match criterion based on texture and motion activity analysis. Extensive experiments have demonstrated that the proposal not only result in better reconstruction, objectively and subjectively, than the reference software model benchmark, but also results in better robustness to different video sequences.

关键词： error concealment error control H.264/JVT video transmission lossy transmission

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Transduction of primary rat hepatocytes with bicistronic retroviral vector

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World Journal of Gastroenterology 2000年第5期6卷 725-729页

作者： Qing Xie dan liao Xia Qiu Zhou Shu Bing Qian Shi Shu Cheng Department of Infectious Disease Ruijin HospitalShanghai Second Medical UniversityShanghai 200025China Hurnan Genetic Therapy Research Center Shanghai Second Medical UniversityShanghai 200025China

INTRODUCTIONHepatocellular transplantation (HCT) could providea therapeutic alternative to orthotopic livertransplantation(OLT) in the treatment of hepaticmetabolic defects and experimental *** appropriate conditions,... 详细信息

关键词： primary hepatocyte recombinant retroviral vector genetic markers gene transfer hepatocellular transplantation polymerase chain reaction

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Biphasic modulation of chemerin peptide-induced calcium flux and ERK phosphorylation by amyloid beta peptide

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中国药理学与毒理学杂志 2017年第10期31卷 1020-1021页

作者： Hao GONG Shuo ZHANG dan liao Richard Dequan YE School of Pharmacy Shanghai Jiao Tong University Institute of Chinese Medical Sciences University of Macao

OBJECTIVE The chemokine-like receptor 1(CMKLR1,Chem R23) is a functional receptor for chemerin,the chemerin-derived nonapeptide(C9),and the amyloid β peptide 1-42(Aβ_(42)).Because these peptides share little sequence homology,studies were conducted to investigate their pharmacological properties and regulation at *** Cells expressing CMKLR1 were incubated with Aβ_(42) before stimulation with a strong agonist,the C9 *** mobilization,c AMP inhibition and MAP kinase activation were *** FRET were determined using CMKLR1 constructs with an ECFP attached to the C-terminus and a Fl As H binding motif embedded in the first intracellular loop(IL1).RESULTS Binding of both Aβ_(42) and the C9 peptide induced CMKLR1 internalization,but only the Aβ_(42)-induced receptor internalization involved clathrin-coated ***,Aβ_(42) but not C9 stimulated β-arrestin 2 translocation to plasma membranes.A robust Ca^(2+)flux was observed following C9 stimulation,whereas Aβ_(42) was ineffective even at micromolar *** its low potency in calcium mobilization assay,Aβ_(42) was able to alter C9-induced Ca^(2+) flux in dose-dependent manner:a potentiation effect at 100 pmol·L^(-1) of Aβ_(42) was followed by a suppression at 10 nmol·L^(-1) and further potentiation at 1 μmol·L^(-1).This unusual and biphasic modulatory effect was also seen in the C9-induced ERK phosphorylation but the dose curve was opposite to that of Ca^(2+) flux and c AMP inhibition,suggesting a reciprocal regulatory *** FRET assay confirmed that Aβ_(42) modulates CMKLR1 rather than its downstream signaling *** These findings suggest Aβ_(42) as an allosteric modulator that can both positively and negatively regulate the activation state of CMKLR1 in a manner that differs from existing allosteric modulatory mechanisms.

关键词： G protein-coupled receptors allosteric modulation fluorescent resonance energy transfer chemokine like receptor 1 chemerin conformational changes

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Accumulation of polycyclic aromatic hydrocarbons from contaminated soil by Kandelia candel

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Acta Oceanologica Sinica 2009年第6期28卷 24-29页

作者： HONG Youwei YUAN Dongxing liao dan LIU Baomin State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China College of Environment and Plant Protection Hainan University Danzhou 71737 China

The purpose of this study was to investigate the accumulation behavior of two typical PAHs, phenanthrene （PHE） and fluoranthene （FLA）, uptaken by the mangrove Kandelia candel in various treated sandy soils. The experiment lasted for three months. Soil and plant samples were collected after 3, 6, 9 and 13 weeks of the incubation and the levels of PAHs were analyzed using a GC/MS （HP6890-5975B）. The results showed that the root accumulations of PHE and FLA were elevated with the increase of the PAH concentrations in the soil. With prolonged exposure time, PHE and FLA concentrations of the roots increased significantly in comparison with the control. PHE and FLA concentrations of root after 13 weeks of treatment ranged from 0.28 to 4.36 #g.g-1 and 0.79 to 35.76 pg.g 1 respectively. The calculated mean values of the root concentration factors were 0.58 for PHE and 0.71 for FLA. This indicated that root accumulation of FLA was greater than PHE, which would result from the higher octanol-water partition coefficient （Kow） of FLA. These results underline the ability of mangroves to remove PAHs from contaminated marine substrates and hence their potential use in bioremediation and the removal of PAHs from the marine food chain.

关键词： accumulation uptake phenanthrene fluoranthene mangrove ecosystem Kandelia candel

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Quantitative proteomic and phosphoproteomic analyses of the hippocampus reveal the involvement of NMDAR1 signaling in repetitive mild traumatic brain injury

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Neural Regeneration Research 2023年第12期18卷 2711-2719页

作者： Zhicheng Tian Zixuan Cao Erwan Yang Juan Li dan liao Fei Wang Taozhi Wang Zhuoyuan Zhang Haofuzi Zhang Xiaofan Jiang Xin Li Peng Luo Department of Neurosurgery Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina The Sixth Regiment School of Basic MedicineFourth Military Medical UniversityXi’anShaanxi ProvinceChina Department of Neurobiology School of Basic MedicineFourth Military Medical UniversityXi’anShaanxi ProvinceChina Medical Experiment Center Shaanxi University of Chinese MedicineXianyangShaanxi ProvinceChina Department of Anesthesiology The Second Hospital of Jilin UniversityJilin UniversityChangchunJilin ProvinceChina School of Life Science Northwest UniversityXi’anShaanxi ProvinceChina Department of Anesthesiology Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina

The cumulative damage caused by repetitive mild traumatic brain injury can cause long-term neurodegeneration leading to cognitive *** cognitive impairment is thought to result specifically from damage to the *** this study,we detected cognitive impairment in mice 6 weeks after repetitive mild traumatic brain injury using the novel object recognition test and the Morris water maze *** staining showed that p-tau expression was increased in the hippocampus after repetitive mild traumatic brain *** staining showed a significant decrease in the total density of neuronal dendritic spines in the hippocampus,as well as in the density of mature dendritic *** investigate the specific molecular mechanisms underlying cognitive impairment due to hippocampal damage,we performed proteomic and phosphoproteomic analyses of the hippocampus with and without repetitive mild traumatic brain *** differentially expressed proteins were mainly enriched in inflammation,immunity,and coagulation,suggesting that non-neuronal cells are involved in the pathological changes that occur in the hippocampus in the chronic stage after repetitive mild traumatic brain *** contrast,differentially expressed phosphorylated proteins were mainly enriched in pathways related to neuronal function and structure,which is more consistent with *** identified N-methyl-D-aspartate receptor 1 as a hub molecule involved in the response to repetitive mild traumatic brain injury,and western blotting showed that,while N-methyl-D-aspartate receptor 1 expression was not altered in the hippocampus after repetitive mild traumatic brain injury,its phosphorylation level was significantly increased,which is consistent with the omics *** of GRP78608,an N-methyl-D-aspartate receptor 1 antagonist,to the hippocampus markedly improved repetitive mild traumatic brain injury-induced cognitive *** conclusion,our findings

关键词： cognitive impairment Grin1 hippocampus learning memory N-methyl-D-aspartate N-methyl-D-aspartate receptor 1 phosphoproteomic proteomic repetitive mild traumatic brain injury(rmTBI) secondary injury

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Traffic-Aware VDC Embedding in Data Center： A Case Study of FatTree

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China Communications 2014年第7期11卷 142-152页

作者： LUO Shouxi YU Hongfang LI Lemin liao dan SUN Gang Key Laboratory of Optical Fiber Sensing and Communications Ministry of Education University of Electronic Science and Technology of China Chengdu 611731 China Institute of Electronic and Information Engineering in Dongguan UESTC Dongguan 523808 China

Virtualization is a common technology for resource sharing in data center. To make efficient use of data center resources, the key challenge is to map customer demands （modeled as virtual data center, VDC） to the physical data center effectively. In this paper, we focus on this problem. Distinct with previous works, our study of VDC embedding problem is under the assumption that switch resource is the bottleneck of data center networks （DCNs）. To this end, we not only propose relative cost to evaluate embedding strategy, decouple embedding problem into VM placement with marginal resource assignment and virtual link mapping with decided source-destination based on the property of fat-tree, but also design the traffic aware embedding algorithm （TAE） and first fit virtual link mapping （FFLM） to map virtual data center requests to a physical data center. Simulation results show that TAE＋FFLM could increase acceptance rate and reduce network cost （about 49% in the case） at the same time. The traffie aware embedding algorithm reduces the load of core-link traffic and brings the optimization opportunity for data center network energy conservation.

关键词： virtual data center embedding switch capacity fat-tree

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基于SAEM-HMM的设备状态诊断模型研究

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系统工程理论与实践 2017年第7期37卷 1910-1918页

作者：廖雯竹李丹重庆大学机械工程学院工业工程系重庆400030

针对设备状态诊断问题,提出了基于模拟退火和期望最大化算法的隐马尔可夫模型(SAEMHMM).该模型针对改进传统隐马尔可夫模型对初值敏感及期望最大化算法容易陷入局部最优的不足,将模拟退火算法与期望最大化算法结合,利用前者具有概率的... 详细信息

针对设备状态诊断问题,提出了基于模拟退火和期望最大化算法的隐马尔可夫模型(SAEMHMM).该模型针对改进传统隐马尔可夫模型对初值敏感及期望最大化算法容易陷入局部最优的不足,将模拟退火算法与期望最大化算法结合,利用前者具有概率的全局收敛性,克服局部最优问题,实现隐马尔可夫模型参数估计过程的优化.最后通过算例分析验证了该模型的可行性与有效性.

关键词：隐马尔可夫期望最大化模拟退火状态诊断

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从传统音乐的三个特性看音乐类非物质文化遗产保护

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中国音乐学 2013年第1期 49-53页

作者：廖丹浙江省金华职业技术学院

非物质文化遗产中的传统音乐(民间音乐)类别在第三批"国家级非物质文化遗产项目"名录和第四批"国家级非物质文化遗产项目代表性传承人"名录中的数量日渐增多,但从传统音乐本身的特殊性、个体性、群体性入手,切入音乐类非物质文化遗产保... 详细信息

非物质文化遗产中的传统音乐(民间音乐)类别在第三批"国家级非物质文化遗产项目"名录和第四批"国家级非物质文化遗产项目代表性传承人"名录中的数量日渐增多,但从传统音乐本身的特殊性、个体性、群体性入手,切入音乐类非物质文化遗产保护的研究还很有限。对传统音乐的这三个特性的强调,目的在于避免因突出代表性而忽略多样性、丰富性,造成音乐标准化、单一化的后果。寄望今后的音乐类非物质文化遗产保护中,民间音乐丰富的区域特色与个人风格都应该拥有"代表",每个区域选择的代表性传承人都应能最大程度地代表一个乐种的艺人群体。

关键词：非物质文化遗产传统音乐的特性保护策略

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