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SYNTHESIS OF MAIN CHAIN LIQUID CRYSTALLINE COPOLYESTERS WITH X-SHAPED TWO-DIMENSIONAL MESOGENIC UNIT AND CROWN ETHER CYCLE

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Chinese Journal of Polymer Science 2005年第5期23卷 549-556页

作者： Jing-wu Wang Shi-jun Zheng Xiao-hui Xu Xing-qi Zhu Shu-yuan Zhang Tie-sheng Li Zi-fa Li Qi-feng Zhou College of Materials and Engineering Zhengzhou UniversityZhengzhou 450052 China Department of Chemistry Zhengzhou UniversityZhengzhou 450052 China Department of Polymer Science and Engineering College of Chemistry and Molecular Engineering Peking University Beijing 100871China

A novel series of main chain liquid crystalline copolyesters with X-shaped two-dimensional mesogenic unit and crown ether cycle of cis-4,4＇-bis（4-hydroxyphenylazo） dibenzo-18-crown-6 was prepared via solution condensation polymerization from 4,4＇-（a;arhexanedioyloxy） dibenzoyl dichloride （MI）, 2,5-bis（p-octyloxybenzoyloxy） hydro-quinone （M2） and cis-4,4＇-bis（4-hydroxyphenylazo） dibenzo-18-crown-6 （M3）. Monomer MI was synthesized by esterification and substitution of adipoyl chloride with p-hydroxybenzoic acid, monomer M2 was synthesized by esterfication and reduction reaction of 2,5-dihydroxybenzoquinone and p-octanoxybenzoyl chloride and monomer M3 was synthesized by diazotization and coupling reaction of cis-diaminodibenzo-18-crown-6 with phenol. The molecular weights of copolyesters are not high, and the intrinsic viscosity [η] of copolyesters ranges from 0.25-0.35. The monomers＇ structures were identified by using elemental analysis, IR, UV, ^1H-NMR, MS, etc. All the copolyesters are yellowish powders and insoluble in THF and CHC13 at room temperature except cPg. The properties of copolyesters were investigated by using GPC, [η] , DSC, TG, WAXD and pom. It was found that all the copolyesters entered into liquid crystal phase when they were heated to above their melting temperature （Tin）. The typical smectic and nematic phase texture can be observed on pom. Their mesophase transition temperature and thermal stability change regularly with varying the content of cis-4,4＇-bis（4-hydroxyphenylazo） dibenzo-18-crown-6 unit in the copolyesters.

关键词： X-shaped two-dimensional mesogenic unit Crown ether Liquid crystalline copolyesters Synthesis.

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Effects of lamivudine on the function of dendritic cells derived from patients with chronic hepatitis B virus infection

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World Journal of Gastroenterology 2007年第34期13卷 4641-4645页

作者： Peng-yuan Zheng Dong-Yun Zhang Gao-Feng Lu Ping-Chang Yang yuan-Ming Qi Bai-Sheng Wang Department of Gastroenterology the Second Affiliated Hospital of ZhengzhouUniversity Zhengzhou 450014 Henan Province China Department of Physiopathology Luohe Medical College Luohe 462002 Henan Province China Department of Pathology and Molecular Medicine McMaster University Hamilton Ontario Canada Department of Biological Engineering Zhengzhou University Zhengzhou 450052 HenanProvince China

AIM： To investigate if the nucleoside analogue lamivudine （lam）, a potent inhibitor of HBV replication, could restore the function of dendritic cells derived from patients with chronic hepatitis B （CHB） in an Asian population.METHODS： Dendritic cells （DCs） derived from mononuclearcytes of patients with chronic HBV infection were cultured in the presence of IL-4, granulocytemacrophage colony-stimulating factors （GM-CSF） and gradient concentrations of lam （0-2 mmol/L）. Cell morphology was observed under light microscopy. Cell surface molecules, including HI_A-DR, CD80, CD83, and CDla, were analyzed with flow cytometry. The concentrations of IL-6 and IL-12 in the supernatant were assayed by ELISA. T cell proliferation was assayed by methyl thiazoM tetrazolium （MTT）.RESULTS： The expression of CDlα on DC treated with 0.5 mmol/L lam （lam-DC 0.5 mmol/L） was significantly higher than that of DC untreated with lam （54.1 ± 4.21 vs 33.57 ± 3.14, P 〈 0.05）, and so was the expression of CD83 （20.24 ± 2.51 vs 12.83 ± 2.12, P 〈 0.05） as well as the expression of HLA-DR （74.5 ± 5.16 vs 52.8 ± 2.51, P 〈 0.05）. Compared with control group, lam-DC group （0.5 mmol/L） secreted significantly more IL-12 （910 ± 91.5 vs 268 ± 34.3 pg/mL, P 〈 0.05）, had lower levels of IL-6 in the culture supernatant （28 ± 2.6 vs 55 ± 7.36 pg/mL, P 〈 0.05）, markedly enhanced the stimulatory capacity in the allogeneic mixed leukocyte reaction （MLR）（1.87 ± 0.6 vs 1.24 ± 0.51, P 〈 0.05）.CONCLUSION： The lower expression of phenotypic molecules and impaired allogeneic mixed lymphocyte reaction function of dendritic cells derived from patients with HBV infection could be restored in vitro by incubation with lam.

关键词： Dendritic cell lamivudine Chronic hepatitisB Immune

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Correction:Links between COVID-19 and Parkinson’s disease/Alzheimer’s disease:reciprocal impacts,medical care strategies and underlying mechanisms

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Translational Neurodegeneration 2023年第1期12卷 572-573页

作者： Pei Huang Lin-yuan Zhang Yu-Yan Tan Sheng-Di Chen Department of Neurology and Institute of Neurology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Department of Neurology Shanghai General HospitalShanghai 200080China Lab for Translational Research of Neurodegenerative Diseases Shanghai Institute for Advanced Immunochemical Studies(SIAIS)Shanghai Tech UniversityShanghai 201210China

Correction to:Translational Neurodegeneration(2023)12:5 https://***/10.1186/s40035-023-00337-1 Following publication of this article[1],three errors were identified about the *** 1:*** TF,Brown L,lam N,Wray F,Knapp P,Forster *** provision for stroke survi-vors and their *** Database Syst Rev.2021;11:*** C,Valdes AM,Polidori L,Antonelli M,Penamakuri S,Nogal A,et *** prevalence,duration,and risk of hospital admission in individuals infected with SARS-CoV-2 during periods of omicron and delta variant dominance:a prospective observational study from the ZOE COVID ***.2022;399:1618-24.

关键词： degeneration Alzheimer reciprocal

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Design of freeform geometries in a MEMS accelerometer with a mechanical motion preamplifier based on a genetic algorithm

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Microsystems & Nanoengineering 2020年第1期6卷 122-135页

作者： Chen Wang Xiaoxiao Song Weidong Fang Fang Chen Ioannis Zeimpekis yuan Wang Aojie Quan Jian Bai Huafeng Liu Gerold Schropfer Chris Welham Michael Kraft College of Optical Science and Engineering Zhejiang UniversityHangzhou 310027P.R.China Department of Electrical Engineering and Computer Science University of LiegeLiege B-4000Belgium ESAT-MICAS University of LeuvenLeuven 3001Belgium PGMF and School of Physics Huazhong University of Science and TechnologyWuhan 430074P.R.China Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 200050P.R.China ORC University of SouthamptonSouthampton SO171BJUK Coventor—A lam Research Company Villebon sur Yvette 91140France

This paper describes a novel,semiautomated design methodology based on a genetic algorithm(GA)using freeform geometries for microelectromechanical systems(MEMS)*** proposed method can design MEMS devices comprising freeform geometries and optimize such MEMS devices to provide high sensitivity,large bandwidth,and large fabrication *** proposed method does not require much computation time or *** use of freeform geometries allows more degrees of freedom in the design process,improving the diversity and performance of MEMS devices.A MEMS accelerometer comprising a mechanical motion amplifier is presented to demonstrate the effectiveness of the design *** results show an improvement in the product of sensitivity and bandwidth by 100%and a sensitivity improvement by 141%compared to the case of a device designed with conventional orthogonal ***,excellent immunities to fabrication tolerance and parameter mismatch are achieved.

关键词： accelerometer algorithm motion

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反思金融深化：新兴市场的稳定与发展

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新金融 2015年第10期 8-13页

作者： IMF课题组 Ratna Sahay Martin Cihak Papa N’Diaye Adolfo Barajas Ran Bi Diana Ayala yuan Gao Annette Kyobe lam Nguyen Christian Saborowski Katsiaryna Svirydzenka Seyed Reza Yousefi 胡妍斌王辰国际货币基金组织

有深度和流动性良好的金融系统,加上有丰富的金融工具可抵御金融冲击,还可以增加一国金融的稳定性。但是金融发展或许存在一个边界,越过此边界进一步发展其收益或将下降。本文通过研究新兴市场发现:一、大部分新兴市场金融进一步发展仍... 详细信息

有深度和流动性良好的金融系统,加上有丰富的金融工具可抵御金融冲击,还可以增加一国金融的稳定性。但是金融发展或许存在一个边界,越过此边界进一步发展其收益或将下降。本文通过研究新兴市场发现:一、大部分新兴市场金融进一步发展仍然对经济的增长和稳定有利。二、金融发展对经济增长的促进作用是倒U型的,在越过高点之后金融深化对要素生产率的促进作用将下降。三、如果金融发展过快,快速深化的金融产业可能引发经济和金融动荡。四、提升金融稳定与金融发展之间没有太大冲突,更好的金融监管有助于提升金融稳定,促进金融发展。五、发展金融机构或金融市场不存在通用的顺序,尽管前者对经济的作用在下降而后者在上升。

关键词：金融发展金融深化新兴市场经济增长金融稳定

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Umbilical Cord Blood Mononuclear Cell Treatment for Neonatal Rats with Hypoxic Ischemia

Umbilical Cord Blood Mononuclear Cell Treatment for Neonatal...

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第十六届中国医师协会神经外科医师年会

作者： Hao LYU Dong Ming SUN Chi Ping NG Wendy S CHENG Jun Fan CHEN Yu Zhong HE Sin Yu lam Zhi yuan ZHENG Guo Dong HUANG Chi Chiu WANG Wise Young Wai Sang POON Division of Neurosurgery Department of SurgeryFaculty of MedicineThe Chinese University of Hong Kong Department of Neurosurgery Shenzhen Key Laboratory of Neurosurgerythe Shenzhen Second People's HospitalFirst Affiliated Hospital of Shenzhen University W.M.Keck Center for Collaborative Neuroscience RutgersState University of New Jersey Department of Neurosurgery Hainan Hospital of People's Liberation Army General Hospital Department of Obstetrics and Gynecology The Chinese University of Hong Kong

Background:Hypoxic-Ischemic Encephalopathy(HIE) occurs when an infant’s brain has not received adequate oxygen and blood supply,resulting in ischemic and hypoxic ***,supportive care and hypothermia therapy have been the standard treatment for ***,there are still over 20% of treated infants died and 19-30% survived with significant *** animal model was first established by Vannucci et al,involving the ligation of one common carotid artery followed by *** this study,we investigated human umbilical cord blood(HUCB) and its two components mononuclear cell(MNC) and red cell fraction(RCF) in both short and long term study using a modified HIE rat ***:In this modified HIE model,both common carotid arteries were occluded,breathing 8% oxygen in a hypoxic chamber for 60-minute,followed by the release of the common carotid arteries ligature,mimicking reperfusion *** cell therapeutic study,cells were intravenously injected to HIE rat pups,and both behavioral and histological changes were assessed at selected time ***:Statistically significant behavioral improvements were demonstrated on Day 7 and 1 month between saline treated HIE rats and UCB/MNC treated ***,at 3 months,the therapeutic improvements were only showed between saline treated HIE animals and MNC treated HIE *** histological analysis one month after cell injection,the number of functional neurons were statistically increased between saline treated HIE and UCB/MNC/RCF treated HIE *** 3 months,the significant increase in functional neurons was only present in MNC treated HIE ***:We have used a bilateral temporary occlusion of 60 minutes,a moderately brain damaged model,for cell therapeutic *** umbilical cord blood(HUCB) mononuclear cell(MNC) therapy showed benefits in neonatal HIE rats in both short and long term behavioral and histological assessments.

关键词： Hypoxic Ischemic Encephalopathy animal model cell therapeutic

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云南少数民族大学生英语学习态度和动机

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云南民族大学学报（哲学社会科学版） 2012年第2期29卷 156-160页

作者：原一川原源李鹏尚云云南师范大学外国语学院云南昆明650092 云南师范大学教育科学与管理学院云南昆明650092

英语学习者的学习动机、态度与效果之间存在着密切关系,这一规律对于文化背景相对特殊的少数民族大学生的英语学习具有同样的意义。通过采取实证定量研究中的问卷法,考察了云南民族院校的837名少数民族本科学生英语学习态度和动机以及... 详细信息

英语学习者的学习动机、态度与效果之间存在着密切关系,这一规律对于文化背景相对特殊的少数民族大学生的英语学习具有同样的意义。通过采取实证定量研究中的问卷法,考察了云南民族院校的837名少数民族本科学生英语学习态度和动机以及与英语水平的关系。问卷包括66个为什么和怎样学习英语的问题,根据Gardner/lam-bert(1972)的二语习得量表改编制成。用SPSS统计软件对数据进行了因子分析和描写性统计,以探索最重要的态度和动机类型,获取了8种态度和动机,以得分由高到低依次是:学习努力程度,外部动机,家长鼓励,教学因素,内部动机,融合型动机,对英语国家人的态度和学习焦虑。相关分析结果表明,学生自我评定英语成绩与学习动机各因子的相关系数由高到低依次排列是:融合型动机,内部动机和外部动机,均呈显著正相关关系。

关键词：态度动机英语成绩云南少数民族大学本科生

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Propofol postconditioning ameliorates hypoxia/reoxygenation induced H9c2 cell apoptosis and autophagy via upregulating forkhead transcription factors under hyperglycemia

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Military Medical Research 2022年第3期9卷 286-302页

作者： Rong-Hui Han He-Meng Huang Hong Han Hao Chen Fei Zeng Xiang Xie Dan-Yong Liu Yin Cai Liang-Qing Zhang Xin Liu Zheng-yuan Xia Jing Tang Department of Anesthesiology Affiliated Hospital of Guangdong Medical UniversityGuangdong57 South Renming Avenue Xiashan DistrictZhanjiang City524000Guandong ProvinceChina Department of Emergency Affiliated Hospital of Guangdong Medical UniversityZhanjiang524000China Department of Anesthesiology the Eighth Affiliated HospitalSun Yat-Sen UniversityGuangzhou518000China Department of Anesthesiology Guangzhou First People’s HospitalThe Second Affiliated Hospital of South China University of TechnologyGuangzhou510000China Department of Anesthesiology The Second Affiliated Hospital and Yuying Children’s HospitalWenzhou Medical UniversityWenzhou325000China Department of Health Technology and Informatics The Hong Kong Polytechnic UniversityHung Hom999077Hong Kong SARChina State Key Laboratory of Pharmaceutical Biotechnology Department of MedicineThe University of Hong KongPok Fu Lam999077Hong Kong SARChina

Background:Administration of propofol,an intravenous anesthetic with antioxidant property,immediately at the onset of post-ischemic reperfusion(propofol postconditioning,P-PostC) has been shown to confer cardioprotection against ischemia–reperfusion(I/R) injury,while the underlying mechanism remains incompletely *** forkhead box O(FoxO) transcription factors are reported to play critical roles in activating cardiomyocyte survival signaling throughout the process of cellular injuries induced by oxidative stress and are also involved in hypoxic postconditioning mediated neuroprotection,however,the role of FoxO in postconditioning mediated protection in the heart and in particular in high glucose condition is ***:Rat heart-derived H9c2 cells were exposed to high glucose(HG) for 48 h,then subjected to hypoxia/reoxygenation(H/R,composed of 8 h of hypoxia followed by 12 h of reoxygenation) in the absence or presence of postconditioning with various concentrations of propofol(P-PostC) at the onset of *** having identified the optical concentration of propofol,H9c2 cells were subjected to H/R and P-PostC in the absence or presence of FoxO1 or FoxO3a gene silencing to explore their roles in P-PostC mediated protection against apoptotic and autophagic cell deaths under ***:The results showed that HG with or without H/R decreased cell viability,increased lactate dehydrogenase(LDH) leakage and the production of reactive oxygen species(ROS) in H9c2 cells,all of which were significantly reversed by propofol(P-PostC),especially at the concentration of 25 μmol/L(P25)(P<0.05,NC ***;HG ***+HR;HG+HR+P12.5 or HG+HR+P25 or HG+HR+P50 ***+HR).Moreover,we found that propofol(P25) decreased H9c2 cells apoptosis and autophagy that were concomitant with increased FoxO1 and FoxO3a expression(P<0.05,HG+HR+P25 ***+HR).The protective effects of propofol(P25) against H/R injury were reversed by silencing FoxO1 or FoxO3a(P<0.05,HG+HR+

关键词： Hypoxia/reoxygenation injury Hyperglycemia High glucose Propofol postconditioning Apoptosis Autophagy Forkhead box O

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基于单-和双-三唑衍生物的三个Cu(Ⅱ)和Cu(Ⅰ)多金属氧簇基配合物的水热合成及光催化性能（英文）

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无机化学学报 2018年第12期34卷 2280-2290页

作者：刘媛媛李欣书张慧敏丁斌无机-有机杂化功能材料化学教育部重点实验室天津师范大学化学学院天津300387 南京大学配位化学国家重点实验室南京210093

在水热条件下,利用多齿的单-和双-三唑衍生物,制备了3种基于多金属氧簇基(pom)的Cu(Ⅱ)和Cu(Ⅰ)杂化材料,即{[Cu(L1)2(Mo4O13)]·2H_2O}n(1),{[Cu1.5(L2)(HL2)(H_2O)(Mo4O13)]·2H2O}n(2),{[Cu2(L3)1.5(Mo4O13)]·H_2O}n(3)(L1=4-pyridine-2-1,2,4-triazole,HL2=3-(4H-1,2,4-triazol-4-yl)benzoic acid,L3=trans-4,4′-azo-1,2,4-triazole)。通过单晶X射线衍射、傅里叶变换红外光谱和粉末X射线衍射分析确定了它们的结构。在1中,Mo4O132-阴离子和Cu(Ⅱ)中心通过双齿L1相互连接,最终形成了二维(2D)poms基的Cu(Ⅱ)杂化金属-有机骨架。在2中,Mo4O132-阴离子和Cu(Ⅱ)中心通过桥接水原子(O18),双齿HL2和三齿L2-相互连接,最终形成了三维(3D)poms基的Cu(Ⅱ)微孔金属-有机骨架。在3中,L3配体桥接相邻的Cu(Ⅰ)中心和Mo4O132-阴离子,最终形成独特的双重穿插结构的3Dpoms基的Cu(Ⅰ)杂化配位框架。光催化实验研究表明,样品1～3对于不同有机染料罗丹明B (RhB)、亚甲基蓝(MB)和甲基橙(MO)都具有很好的光催化降解能力。

关键词：三唑 Cu (Ⅱ) Cu(Ⅰ) 多金属氧簇光催化

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Lorenz系统通向混沌的道路

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大连理工大学学报 2006年第4期46卷 582-587页

作者：王兴元骆超大连理工大学电子与信息工程学院辽宁大连116024

研究了Lorenz系统的非线性动力学.采用一维时间序列相空间重构技术和系统混沌的定量判据准则,揭示出Lorenz系统从规则运动转化到混沌运动所具有的普适特征:该系统可通过pom eau-M annev ille途径走向混沌,且其间歇性与Hop f分岔和倍周... 详细信息

研究了Lorenz系统的非线性动力学.采用一维时间序列相空间重构技术和系统混沌的定量判据准则,揭示出Lorenz系统从规则运动转化到混沌运动所具有的普适特征:该系统可通过pom eau-M annev ille途径走向混沌,且其间歇性与Hop f分岔和倍周期分岔有关,在这些途径上既可观察到锁相和准周期运动,也可观察到类似于Lorenz吸引子的奇怪吸引子.本研究成果有助于理解最终的混沌状态的性质.

关键词： Lorenz系统相空间重构技术混沌的定量判据准则分岔通向混沌的道路

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