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水热法制备聚苯胺及其铁氧化物纳米复合材料

高等学校化学学报 2013年第5期34卷 1303-1308页

作者：刘红缨王双宝朱英江雷中国矿业大学(北京)化学与环境工程学院北京100083 北京航空航天大学化学与环境学院北京100191

利用水热法与无模板自组装法相结合,以三氯化铁为氧化剂、掺杂剂和反应物,制备了聚苯胺及其铁氧化物纳米复合材料.结果表明,通过改变三氯化铁的浓度可以调控产物的微观结构和组成.当三氯化铁的浓度≤0.13 mol/L时,产物组成为未掺杂的低... 详细信息

利用水热法与无模板自组装法相结合,以三氯化铁为氧化剂、掺杂剂和反应物,制备了聚苯胺及其铁氧化物纳米复合材料.结果表明,通过改变三氯化铁的浓度可以调控产物的微观结构和组成.当三氯化铁的浓度≤0.13 mol/L时,产物组成为未掺杂的低聚苯胺与α-Fe2.3的复合纳米材料,其微观结构为纳米颗粒组装成的椭球体和准立方体;当三氯化铁的浓度≥0.2. mol/L时,产物组成为掺杂态聚苯胺,其微观结构为纳米片层结构组装成的微米级大丽花球;并且产物的粒径随三氯化铁浓度的增大而增大.利用扫描电子显微镜、红外光谱、紫外-可见光谱、X光电子能谱及X射线衍射等手段对产物的微观结构和组成进行了表征,并探讨了产物的形成机理.

关键词：水热法聚苯胺铁氧化物纳米复合材料

DNA methylation is involved in regulation of miR-2.0 expression in embryonic neural progenitor cells

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DNA methylation is involved in regulation of miR-210 express...

Probing light DM via the Migdal effect with spherical proportional counter

中国生理学会第2.届全国会员代表大会暨生理学学术大会

作者： lei XIONG~(1,2.,Zhao-Hui LIU~1,Tong ZHAO~1,Xin HUANG~1,Li-Ying WU~1,Hong-Bing SHU~2.Ling-Ling zhu~(1,*), Ming FAN~(1,*) 1 Department of Brain protection and Plasticity,Institute of Basic Medical Sciences,Beijing 100850,China 2.College of Life Science, Wuhan University,Wuhan 430072.China

Introduction:MicroRNA(miRNA) plays critical roles in a large number of cellular processes,including neural development,cell survival and cell *** previous work showed a link between miRNA expression and hypoxia,a neural stem/progenitor cells(NPCs) microenvironment ***-based expression profiles revealed that a specific spectrum of miRNAs in NPCs were up-regulated under hypoxic conditions,including miR-2.0,which via a hypoxia inducible factor-1(HIF-1)-dependent ***,we demonstrate that besides the HIF-1 pathway,the expression of miR-2.0 in NPCs is also regulated by DNA methylation under ***:First,we detectd the expression level of miR-2.0 in NPCs treated with the DNA-demethylation agent 5-aza-2.-deoxycytidine(AZA) by ***,we detected the methylation rate of miR-2.0 in NPCs exposed to different oxygen concentration by bisulfite *** then determined the cell survival and apoptosis after miR-2.0 over-expression in NPCs by Cell Counting kit-8 and TUNEL ***:MiR-2.0 is embedded in a CpG island,and its expression level is increased in NPCs treated with DNA methylation inhibitor(AZA) even under *** sequencing of multiple independent miR-2.0 clones show a decrease from 2.% methylation in NPCs under 2.%O to 18%under 3%O,or 12.under 0.3%*** find a CpG dinucleotide especially changed from hemimethylation under 2.%O to approach little-methylation under 3%or 0.3%O. Hypoxia results in demethylation of miR-2.0,and hypomethylation can lead to epigenetic activation of the *** addition,overexpression of miR-2.0 increases the survival rate of NPCs exposed to extreme ***: These results demonstrate that hypoxia can up-regulate the expression of miR-2.0 by decreasing the methylation level of the genome DNA,which is an important element of NPCs response to extreme hypoxia by affecting cell survival.

关键词： miR-2.0 hypoxia methylation neural stem or progenitor cells cell survival

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Chinese Physics C 2023年第12期47卷 169-179页

作者：顾玉超唐杰武雷祝斌 Department of Physics and Institute of Theoretical Physics Nanjing Normal UniversityNanjing 210023China School of Physics Southeast UniversityNanjing 211189China Department of Physics Yantai UniversityYantai 264005China

Owing to its low electronic noise and flexible target materials, the Spherical Proportional Counter(SPC)with a single electron detection threshold can be utilized to search for sub-GeV dark matter(DM). In this study, we investigate the prospects for light DM direct detection via the DM-nucleus Migdal effect in the DARKSPHERE detector. We consider different DM velocity distributions and momentum-transfer effects. For Xenon and Neon targets, we find that the DM mass mDM can be probed down to as low as m_(DM)~ O(10) MeV, and the derived bounds on the DM-nucleus scattering cross section σ_(n) are sensitive to the high-velocity tails of the DM velocity distribution,which can be altered by orders of magnitude for the different DM velocity distributions in the region mDM< 10MeV.

关键词： dark matter Migdal effect dark matter velocity distribution NEWs-G experiment

The Lyman-alpha Solar Telescope (LST) for the ASO-S mission——Ⅰ. Scientific objectives and overview

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Research in Astronomy and Astrophysics 2019年第11期19卷 23-32页

作者： Hui Li Bo Chen Li Feng Ying Li Yu Huang Jing-Wei Li lei Lu Jian-Chao Xue Bei-Li Ying Jie Zhao Yu-Tong Yang Wei-Qun Gan Cheng Fang Ke-Fei Song Hong Wang Quan-Feng Guo Ling-Ping He Bo zhu Cheng zhu lei Deng Hai-Chao Bao Cai-Xia Cao Zhong-Guang Yang Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210034China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Changchun Institute of Optics FineMechanics and PhysicsChinese Academy of SciencesChangchun 130033China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi’an 710119China Innovation Academy for Microsatellites Chinese Academy of SciencesShanghai 201210China

As one of the payloads for the Advanced Space-based Solar Observatory(ASO-S)mission,the Lyman-alpha(Lyα)Solar Telescope(LST)is aimed at imaging the Sun and the inner corona up to 2.5 R⊙(mean solar radius)in both the Lyα(12..6 nm)and visible wavebands with high temporo-spatial resolution,mainly targeting solar flares,coronal mass ejections(CMEs)and filaments/*** observations allow us to trace solar eruptive phenomena from the disk center to the inner corona,to study the relationships between eruptive prominences/filaments,solar flares and CMEs,to explore the dynamical processes and evolution of solar eruptions,to diagnose solar winds,and to derive physical parameters of the solar *** is actually an instrument suite,which consists of a Solar Disk Imager(SDI),a Solar Corona Imager(SCI),a White-light Solar Telescope(WST)and two Guide Telescopes(GTs).This is the first paper in a series of LST-related *** this paper,we introduce the scientific objectives,present an overview of the LST payload and describe the planned *** detailed design and data along with potential diagnostics are described in the second(Paper II)and third(Paper III)papers,respectively,appearing in this issue.

关键词： Sun flares-Sun coronal mass ejections(CMEs)-Sun filaments,prominences-Sun corona-Sun chromosphere-Sun UV radiation

Integrated physiologic,proteomic,and metabolomic analyses of Malus halliana adaptation to saline–alkali stress

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Horticulture Research 2019年第1期6卷 585-603页

作者： Xu-mei Jia Yan-fang zhu Ya Hu Rui Zhang Li Cheng Zu-lei zhu Tong Zhao Xiayi Zhang Yan-xiu Wang College of Horticulture Gansu Agricultural University730070 LanzhouChina Northwest Institute of Eco-Environment and Resources Chinese Academy of Science730000 LanzhouChina

Saline–alkali stress is a severely adverse abiotic stress limiting plant *** halliana Koehne is an apple rootstock that is tolerant to saline–alkali *** understand the molecular mechanisms underlying the tolerance of *** to saline–alkali stress,an integrated metabolomic and proteomic approach was used to analyze the plant pathways involved in the stress response of the plant and its regulatory mechanisms.A total of 179 differentially expressed proteins(DEPs)and 140 differentially expressed metabolites(DEMs)were *** found that two metabolite-related enzymes(PPD and PAO)were associated with senescence and involved in porphyrin and chlorophyll metabolism;six photosynthesis proteins(PSAH2.PSAK,PSBO2.PSBP1,and PSBQ2.were significantly upregulated,especially PSBO2.and could act as regulators of photosystem II(PSII)***,acting as a signaling molecule,directly mediated the accumulation of D-phenylalanine,tryptophan,and alkaloid(vindoline and ecgonine)and the expression of proteins related to aspartate and glutamate(ASP3,ASN1,NIT4,and GLN1−1).These responses play a central role in maintaining osmotic balance and removing reactive oxygen species(ROS).In addition,sucrose signaling induced flavonoid biosynthesis by activating the expression of CYP75B1 to regulate the homeostasis of ROS and promoted auxin signaling by activating the expression of T31B5_170 to enhance the resistance of *** to saline–alkali *** decrease in peroxidase superfamily protein(PER)and ALDH2.4 during lignin synthesis further triggered a plant saline–alkali ***,this study provides an important starting point for improving saline–alkali tolerance in *** via genetic engineering.

关键词： alkali removing starting

Increasing targeting scope of adenosine base editors in mouse and rat embryos through fusion of TadA deaminase with Cas9 variants

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Protein & Cell 2018年第9期9卷 814-819页

作者： lei Yang Xiaohui Zhang Liren Wang Shuming Yin Biyun zhu Ling Xie Qiuhui Duan Huiqiong Hu Rui Zheng Yu Wei Liangyue Peng Honghui Han Jiqin Zhang Wenjuan Qiu Hongquan Geng Stefan Siwko Xueli Zhang Mingyao Liu Dali Li East China Normal University and Shanghai Fengxian DistrictCentral Hospital Joint Center for Translational Medicine ShanghaiKey Laboratory of Regulatory Biology School of Life SciencesEast China Normal University Shanghai 200241 China Fengxian Hospital Affiliated to Southern Medical University Shanghai 201499 China Xinhua Hospital Shanghai Jiao Tong University School ofMedicine Shanghai 200092 China School of Life Sciences Hunan Normal University Changsha 410081 China Bioray Laboratories Inc. Shanghai 200241 China Department of Molecular and Cellular Medicine The Institute of Biosciences and Technology Texas AM University Health Science Center Houston TX 77030 USA

Dear Editor, The clustered regularly interspaced short palindromic repeat （CRISPR） system has been widely adapted to genome editing to either introduce or correct genetic mutations （Wang et al., 2.16）. However, due to competition with the dominant non-homologous end-joining （NHEJ） pathway, precise genome modifications through Cas9-stimulated homologous recombination （HR） is inefficient. Through fusion of cytidine deaminases, APOBEC1 （apolipoprotein B editing complex 1） or AID （activation-induced deaminase）, with Cas9 variants, several groups have developed the cytidine base editor （BE） systems （Komor et al., 2.16; Li et al., 2.18; Nishida et al., 2.16）. The BE system achieves programmable conversion of C-G base pairs to T.A without double-stranded DNA cleavage （Zhou et al., 2.17）. More recently, adenine base editors （ABEs）, which efficiently convert A-T base pairs to G-C in genomic DNA, have been developed via fusion of an engineered tRNA adenosine deaminase （ecTadA from Escherichia coh） with nCas9 （Gaudelli et al., 2.17）. The ABE system has quickly been adapted to generate disease models and correction of genetic disease in mice （Ryu et al., 2.17; Liu et al, 2.18）. However, whether the editing efficiency and the targeting scope of ABE could be improved is largely unexplored. In this study, we describe the efficient generation of base-edi- ted mice and rats modeling human diseases through ABEs with highest efficiency up to 100%. We also demonstrate an increase of ABE activity through injection of chemically modified tracrRNA and crRNA in mouse zygotes, and the expansion of editing scope by fusion of an ecTadA mutant to SaCas9n-KKH and Casgn-VQR variants in both cells and embryos. Our study suggests that the ABE system is a powerful and convenient tool to introduce precise base conversions in rodents.

关键词： GENOMIC DNA CRISPR-CAS9

牛源金黄色葡萄球菌单链抗体对奶牛乳腺炎的治疗效果评价

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畜牧与兽医 2018年第7期50卷 127-131页

作者：金耀忠王曼王婷婷何随彬林赛峰张蕾金盈宇叶承荣朱建国上海市浦东新区动物疫病预防控制中心上海201299 上海交通大学农业与生物学院上海兽医生物技术重点实验室上海200240 南京农业大学动物医学院江苏南京210095 上海希迪乳业有限公司上海201302

本文首先对患隐性乳腺炎的50头奶牛采取奶样,并对奶样进行了细菌分离鉴定及PCR检测,共检出金黄色葡萄球菌2.株;随后对分离到的金黄色葡萄球菌进行了药敏试验,结果显示70%的金黄色葡萄球菌对青霉素产生了耐药性。为了研究针对金黄色葡萄... 详细信息

本文首先对患隐性乳腺炎的50头奶牛采取奶样,并对奶样进行了细菌分离鉴定及PCR检测,共检出金黄色葡萄球菌2.株;随后对分离到的金黄色葡萄球菌进行了药敏试验,结果显示70%的金黄色葡萄球菌对青霉素产生了耐药性。为了研究针对金黄色葡萄球菌全菌抗原的单链抗体对奶牛乳腺炎的治疗效果,将表达单链抗体的重组质粒通过无针注射器注射到患病奶牛的乳腺（600μg/乳区）,48 h后再以相同的剂量注射一次。14 d后,奶样的加利福尼亚乳腺炎试验（California Mastitis Test,CMT）结果显示,治疗奶牛乳腺炎的有效率为83.33%,其中2.完全治愈。定期采集试验奶牛的乳样,并用PCR方法进行检测,发现第二次注射后的14 d内,奶样中未检测到重组质粒,说明重组质粒不能在奶牛体内长期残留。本研究为奶牛乳腺炎治疗抗体的研发提供了理论依据。

关键词：奶牛乳腺炎金黄色葡萄球菌单链抗体

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室内直达与非直达环境无线传播综合信道建模

物理学报 2015年第17期64卷 56-65页

作者：周杰刘鹏黄雷朱兴宇邵根富南京信息工程大学电子与信息工程学院南京210044 日本国立新泻大学工学部新泻950-2181 杭州电子科技大学通信工程学院杭州310000

本文主要针对室内无线传播信道直达(line of sight,LOS)与非直达(no line of sight,NLOS)环境,引入参考模型研究其建模设计及其相关统计特性.文中提出了一种基于几何散射模型的综合改进室内参考信道模型,假设将无限数量的散射体均匀分... 详细信息

本文主要针对室内无线传播信道直达(line of sight,LOS)与非直达(no line of sight,NLOS)环境,引入参考模型研究其建模设计及其相关统计特性.文中提出了一种基于几何散射模型的综合改进室内参考信道模型,假设将无限数量的散射体均匀分布在三维空间的一个二维(two dimensional,2.)水平面上.本文推导了电磁波达信号到达角(angle of arrival,AOA)概率分布函数(probability density function,PDF)、多普勒功率谱密度(power spectral Density,PSD)、时间自相关函数(autocorrelation function,ACF)的解析表达式,并分析其重要参数对函数的影响.此外,本文还通过非现实参考模型提出了一种高效的SOC(Sum of Cisoids)信道仿真模型,同时提出了设计SOC信道仿真模型的两种有效参数计算方法,并比较两者的计算性能.仿真结果表明,信道仿真模型的统计特性与参考模型相匹配,即室内参考模型可以通过的SOC信道仿真模型来近似,同时信道仿真模型可以很好的应用于评估室内无线通信系统的性能,拓宽了室内无线信道建模的研究,同时减少实现开支.

关键词：波达信号多普勒功率谱密度散射体参考信道模型

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新疆绿洲城市扩展与空间形态变化分析

水土保持学报 2009年第6期23卷 252-256页

作者：刘雅轩张小雷雷军朱磊王涛中国科学院新疆生态与地理研究所乌鲁木齐830011 中国科学院研究生院北京100049 新疆乌鲁木齐市房屋产权交易管理中心乌鲁木齐830000

绿洲城市是绿洲内人类生产、生活的集聚中心,也是人地关系最为敏感的区域。绿洲城市的空间形态及其变化的动力机制都显示出与其它地区不同的特征,其复杂性和多样性对城市形态学的理论研究具有特殊价值。研究基于1990年、2.00年和2.07年L... 详细信息

绿洲城市是绿洲内人类生产、生活的集聚中心,也是人地关系最为敏感的区域。绿洲城市的空间形态及其变化的动力机制都显示出与其它地区不同的特征,其复杂性和多样性对城市形态学的理论研究具有特殊价值。研究基于1990年、2.00年和2.07年Landsat遥感影像,借助GIS手段,以新疆18个绿洲城市为研究对象,定量分析了干旱区典型绿洲城市近2.年城市扩展与空间形态变化的时空特征。结果表明:(1)新疆绿洲城市扩展速度与强度均较高的主要位于天山北坡地区,较低的主要集中在东疆和南疆。总体而言,扩展速度与强度值低于中东部城市。(2.乌鲁木齐等位于山前凹陷带、山前盆地或地形复杂老绿洲的城市具有较高的分维数;而年轻城市大多在平原地区,分维数较低,结构紧凑。(3)1990-2.00年,城市扩展与非农业人口增长之间的关系协调度不足,2.00年后得到有效改善。绿洲城市人均建设用地面积普遍略大于国家标准,弹性系数较低的城市应适度扩展;弹性系数较高的城市应放缓扩展速度。

关键词：绿洲城市城市扩展空间形态遥感