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M-IDG结构小型超宽带衰减器的FDTD仿真和实现

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微波学报 2000年第3期16卷 231-236页

作者：张琰高本庆李镇杨春涛北京理工大学电子工程系北京100081 中国航天总公司二院203研究所北京100854

本文在分析新型传输线 -微带加载插入介质波导 (M- IDG)基本特性的基础上 ,用FDTD法仿真设计了小型、超宽带衰减器。电路尺寸分 5.1× 2 5mm2 和 5.1× 40 mm2 两种。对于1 0 d b衰减器 ,工作频带 0 .5～ 1 8GHz内衰减起伏小于 1 .0 d b... 详细信息

本文在分析新型传输线 -微带加载插入介质波导 (M- IDG)基本特性的基础上 ,用FDTD法仿真设计了小型、超宽带衰减器。电路尺寸分 5.1× 2 5mm2 和 5.1× 40 mm2 两种。对于1 0 d b衰减器 ,工作频带 0 .5～ 1 8GHz内衰减起伏小于 1 .0 d b;30 d b衰减器 ,在 2 .0～ 1 8GHz带宽内 ,衰减起伏小于 2 .5d b。实测结果与 FDTD仿真结果基本吻合。

关键词：介质波导 M-IDG 超宽带衰减器 FDTD仿真

Vertical adaptive radiation in ocean Prochlorococcus:Evolutionary implications of the Ch1 b/a ratio from molecular evidence

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Progress in Natural Science:Materials International 2009年第11期19卷 1561-1568页

作者： Song Qin~(a,*),Yinchu Wang~(a,b) a Yantai Institute of Coastal Zone Research for Sustainable Development,Chinese Academy of Sciences,Yantai 264003,China b Graduate University of Chinese Academy of Sciences,beijing 100049,China Yantai Institute of Coastal Zone Research for Sustainable Development Chinese Academy of Sciences Yantai 264003 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Prochlorococcus is a marine cyanobacterium of global *** ecotypes are adapted to either high-light(HL) or low-light (ll) *** ratio between chlorophyll(Chl) a and b is a distinguishing characteristic of these two ***,how this ratio evolved in Prochlorococcus during this ecotype differentiation remains *** analyses reveal that the ancestor of Prochlorococcus was typically low-light *** ll ecotype showed a stagnant evolution,and the HL ecotype was recently *** was an adaptive radiation after directional evolution in the Chl bla ratio *** in chlorophyllide a oxygenase(CAO) and positive selection on Clp protease contributed to the directional evolution of *** recombinant fragments of CAO were correlated with a large group of shared coevolving *** of positive selection was found in both subunits of *** bla ratio evolution,as annotated by molecular evidence,appears to be among the crucial reasons that explain how Prochlorococcus has become the dominant photosynthetic organism in the ocean.

关键词： Prochlorococcus Ch1 b/a ratio Adaptive evolution Trait evolution Ecotype differentiation

Modification of Hole Transport Layers for Fabricating High Performance Non-fullerene Polymer Solar Cells

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Chinese Journal of Chemistry 2020年第8期38卷 817-822页

作者： b.Hari babu Chengkun Lyu Hongwei Zhang Zhihao Chen Fenghong Li Lin Feng Xiao-Tao Hao School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinanShandong 250100China State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryJilin UniversityChangchunJilin 130012China ARC Centre of Excellence in Exciton Science School of ChemistryUniversity of MelbourneParkvilleVictoria 3010Australia

Interfacial engineering is expected to be a feasible strategy to improve the charge transport properties of the hole transport layer(HTL),which is of crucial importance to boost the device performance of organic solar cells(OSCs).In this study,two types of alcohol soluble materials,2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane(F4-TCNQ)and di-tetrabutylammoniumcis-bis(isothiocyanato)bis(2,2'-bipyridyl-4,4'-dicarboxylato)ruthenium(ll)(N719)dye were selected as the dopant for *** doping of F4-TCNQ and N719 dye in poly(ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)with and without integrating a graphene quantum-dots(G-QDs)layer has been explored in poly[[2,6'-4-8-di(5-ethylhexylthienyl)benzo[1,2-b:3,3-b]dithiophene][3-fluoro-2[(2-ethylhexyl)carbonyl]thieno[3,4-b]thio-phenediyl:(2,2'-((2Z,2'Z)-(((4,4,9,9-tetrakis(4-hexylphenyl)-4,9-dihydro-s-indaceno[1,2-b:5,6-b']dithiophene-2,7-diyl)bis(4-((2-ethylhexyl)oxy)thiophene-5,2-diyl))bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile(PTb7-Th:IEICO-4F)*** power conversion efficiency of the non-fullerene OSCs has been increased to 10.12%from 8.84%.The influence of HTL modification on the nano-morphological structures and photophysical properties is analyzed based on the comparative studies performed on the control and modified *** use of chemical doping and bilayer strategy optimizes the energy level alignment,nanomorphology,hole mobility,and work-function of HTL,leading to considerable reduction of the leakage current and recombination *** work demonstrates that the doping of HTL and the incorporation of G-QDs layer to constitute a bilayer HTL is an promising strategy to fabricate high performance non-fullerene polymer solar cells.

关键词： doping Solar dye

叶下珠提取物对体外四氯化碳损伤肝细胞的保护作用

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中国组织工程研究与临床康复 2007年第25期11卷 4909-4912页

作者：李兰岚范适饶力群唐忠海湖南农业大学生物科学技术学院湖南省长沙市410128

目的:观察叶下珠不同溶剂提取物对体外四氯化碳损伤肝细胞的保护作用。方法:实验于2005-07/2006-09在湖南农业大学完成。①称取3份适量叶下珠药材,分别用水、体积分数为0.95的乙醇、体积分数为0.70的乙醇各回流提取3次,分别得到各自的... 详细信息

目的:观察叶下珠不同溶剂提取物对体外四氯化碳损伤肝细胞的保护作用。方法:实验于2005-07/2006-09在湖南农业大学完成。①称取3份适量叶下珠药材,分别用水、体积分数为0.95的乙醇、体积分数为0.70的乙醇各回流提取3次,分别得到各自的提取物,实验时稀释到所需质量浓度(1,10,100g/L)。②称取叶下珠适量,用体积分数为0.70的乙醇回流提取3次,将其提取液浓缩至干,然后用200～300mL水溶解,其溶解液分别用石油醚、氯仿、乙酸乙酯、正丁醇依次提取,将各提取液浓缩制成干粉,得各自提取物,实验时稀释到所需质量浓度(1,10,100g/L)。③取生长良好的L-02细胞,制成单个细胞悬液以5×108L-1分别接种于96孔板和24孔板,培养24h后,分为正常组,损伤组,各提取物组。损伤组细胞用含有10mmol/L四氯化碳培养液培养4h。各提取物组预先加叶下珠各提取物干预1h后,再换成含有10mmol/L四氯化碳培养液,继续培养4h,收集上清液用来测谷丙转氨酶活性、谷草转氨酶活性、丙二醛的含量以及用MTT法测定细胞的存活率。结果:①损伤组的谷丙转氨酶活性、谷草转氨酶活性、丙二醛水平明显高于正常组,而经过叶下珠提取物预先处理过的细胞,其谷丙转氨酶活性、谷草转氨酶活性、丙二醛水平显著低于损伤组,各提取物中以100g/L体积分数为0.70的乙醇回流提取物效果最好,而且各提取物对细胞的保护呈剂量依赖关系。②体积分数为0.70的乙醇提取物的不同溶剂提取物组谷丙转氨酶活性、谷草转氨酶活性、丙二醛水平显著低于损伤组,对细胞的保护作用与剂量呈一定剂量依赖性关系,其中以100g/L乙酸乙酯提取物对细胞抗四氯化碳损伤作用效果最为明显。③MTT法测定结果表明,四氯化碳损伤后的损伤组细胞活性明显下降,仅为正常组的25.5%。而预先用叶下珠提取物处理过的细胞,其存活率明显高于损伤组,叶下珠体积分数为0.70的醇提物及其乙酸乙酯提取物组效果最为明显,且存在明显剂量效应关系。结论:叶下珠体积分数为0.70的乙醇提取物及其乙酸乙酯提取物对四氯化碳损伤肝细胞有很好的保护作用,其中以质量浓度为100g/L时,效果最为显著。

关键词：叶下珠四氯化碳 L-02肝细胞损伤

Preliminary study on the production of transgenic mice harboring hepatitis b virus X gene

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World Journal of Gastroenterology 1998年第6期4卷 81-84页

作者： ZHU Huan Zhang 1, CHENG Guo Xiang 2, CHEN Jian Qu 2, KUANG Shu Yuan 3, CHENG Yong 2, ZHANG Xin Li 1, ll Hou Da 2, XU Shao Fu 2, SHI Jing Quan 1, QIAN Geng Sun 3 and GU Jian Ren 3

AIM To establish transgenic mice lineage xharboring hepatitis b virus X gene and to provide an efficient animal model for studying the exact role of the Hbx gene in the process of hepatocarcinogenesis. METHODS The Hbx transgenic mice were produced by microinjecting the construct with X gene of HbV (subtype adr) DNA fragment into fertilized eggs derived from inbred C57 bL/6 strain; transgenic mice were identified by using Nested PCR; expression and phenotype of Hbx gene were analyzed in liver from transgenic mice at the age of 8 weeks by RT PCR, pathologic examination and periodic acid schiff staining (PAS), respectively. RESULTS Five hundred and fourteen fertilized eggs of C57 bL/6 mice were microinjected with recombinant retroviral DNA fragment, and 368 survival eggs injected were transferred to the oviducts of 18 pseudopregnant recipient mice, 8 of them became pregnant and gave birth to 20 F1 offspring. Of 20 offsprings, four males and two females carried the hybrid gene (Hbx gene). Four male mice were determined as founder, named X1, X5, X9 and X15. These founders were back crossed to set up F1 generations with other inbred C57bL/6 mice or transgenic littermates, respectively. Transmission of Hbx gene in F1 offspring of X1, X5 and X9 except in X15 followed Mendelian rules. The expression of Hbx mRNA was detected in liver of F1 offspring from the founder mice (X1 and X9), which showed vacuolation lesion and glycogen positive foci. CONCLUSION Transgenic mice harboring Hbx gene were preliminarily established.

关键词： hepatitis b virus gene, viral transgenic animals liver neoplasms diseases models, animal

冷冻血液性心脏停搏液与冷冻晶体心脏停搏液的比较:1440例行冠脉搭桥术患者的前瞻性随机研究

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世界核心医学期刊文摘（心脏病学分册） 2005年第4期1卷 60-61页

作者： vrum E. Tangen G. T.ll.fsrud S. 孟欣 Oslo Heart Center Oslo Norway Dr.

Objectives A large number of experimental studies have indicated that blood ca rdioplegia might be superior to crystalloid cardioplegia for myocardial protecti on during ischemic arrest. However, no prospectively randomized studies of large patient series have been undertaken to prove potential differ ences in clinical course. Methods Over a 52-month period, all patients undergoi ng on-pump coronary artery bypass operated on by 2 surgeons were prospectively randomized to receive either cold crystalloid cardioplegia(group C) or cold bloo d cardioplegia(group b) during aortic crossclamping. Results Altogether, 1440 pa tients aged 37 to 89 years (median, 66 years) entered the study(group C, n=719; group b, n=721). The groups were comparable in all major demographic, preoperati ve, and operative variables. The clinical course turned out to be nearly identic al for both groups. No statistically significant differences were seen concernin g spontaneous sinus rhythm after aortic declamping, use of inotropic drugs or in tra-aortic b.lloon pumping, postoperative ventilatory support, bleeding and rat e of allogeneic blood transfusions, perioperative myocardial infarction, episode s of atrial fibrillation, stroke or minor neurologic dysfunction, renal function , infections, physical rehabilitation, or mortality. Also, in subgroups of patie nts at higher operative risk(female sex, age >70 years, unstable angina, diabete s, emergency operation, ejection fraction 50 minutes , andEuroSCORE >4), no statistically significant differences could be demonstrat ed between the groups. Conclusions There were no significant differences whether myocardial protection was performed with cold blood cardioplegia or cold crysta lloid cardioplegia during aortic crossclamping in patients undergoing coronary a rtery bypass grafting. The extra costs related to blood cardioplegia might be sa ved. Copyright.

关键词：晶体心脏停搏液冠脉搭桥术血液性随机研究松开主动脉钳夹手术危险主动脉横断无显著性差异临床过程外科医生

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心仪和谐——艾兴多夫《月夜》赏析

德语学习 2010年第4期 9-12页

作者： Heinrich b.ll 唐艺军北京外国语大学德语系湘潭大学外国语学院德语系

《月夜》这首诗由约瑟夫·封·艾兴多夫于1837年创作，是一首典型的浪漫主义抒情诗。诗歌充溢着对天地之间的和谐以及对自由的渴望，这种氛围和渴念与抒情主人公及其与自然关系，体现了诺瓦利斯“世界必须浪漫化”的要求。从中亦可看出... 详细信息

《月夜》这首诗由约瑟夫·封·艾兴多夫于1837年创作，是一首典型的浪漫主义抒情诗。诗歌充溢着对天地之间的和谐以及对自由的渴望，这种氛围和渴念与抒情主人公及其与自然关系，体现了诺瓦利斯“世界必须浪漫化”的要求。从中亦可看出诗人的情感和思想境界。

关键词：《月夜》艾兴和谐赏析抒情主人公浪漫主义诺瓦利斯思想境界

MiR-210 suppresses bNIP3 to protect against the apoptosis of neural progenitor cells

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MiR-210 suppresses BNIP3 to protect against the apoptosis of...

Protein-based profiling of the human IgA1 clonal repertoire revealed shared clones of serum polymeric IgA1 and milk secretory IgA1

中国神经科学学会第十届全国学术会议

作者： F WANG L XIONG X HUANG T ZHAO LY WU ZH LIU X DING S LIU Y WU Y ZHAO K WU ll ZHU M FAN Department of Cognitive Sciences Beijing Institute of Basic Medical Sciences

Objective MiR-210 is a hypoxia-inducible factor（HIF）-1 target gene and is the most consistently and predominantly upregulated miRNA in response to hypoxia in various cancer cell *** Our recent study shows that hypoxia increased miR-210 expression in neural progenitor cells（NPCs） in a time-dependent ***,the role of miR-210 in NPCs remains *** the identification of the miR-210 putative target genes,we demonstrated that the bcl-2 adenovirus E1b 19 kDa-interacting protein 3（bNIP3）,which is regulated by HIF-1 and activates cell death,is regulated by miR-210 in NPCs under ***,the over-expression of miR-210decreased apoptosis in NPCs,and the inhibition of miR-210 expression remarkably increased the number of TUNEL-positive NPCs by 30%in response to ***,miR-210 mimics reduced both bNIP3 protein expression and the translocation of AIF into the nucleus,which reduced cell death,whereas miR-210 inhibitors reversed this process,leading to cell death during *** we report a novel feedback loop of bNIP3 regulation in NPCs under ***-1 is activated under hypoxia and then induces the expression of both bNTP3 and *** upregulation of miR-210 then directly suppresses bNTP3 expression to maintain the survival of NPCs under *** negative feedback regulation might partially contribute to protection against hypoxia-induced cell death via the inhibition of AIF nuclear translocation.

关键词： miR-210 hypoxia bNIP3 neural progenitor cells

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Cellular & Molecular Immunology 2023年第3期20卷 305-307页

作者： Jan Novak Matthew b.Renfrow R.Glenn King Colin Reily Todd J.Green Department of Microbiology University of Alabama at BirminghamBirminghamALUSA Department of biochemistry and Molecular Genetics University of Alabama at BirminghamBirminghamALUSA

Human adaptive immunity involves the production and secretion of antibodies by differentiated b cells(ie.,antibody-secreting cells,also called plasma cells)in response to *** secreted antigen-specific antibodies are immunoglobulins that are present at substantial concentrations in blood,mucosal secretions,and breast ***,human immunoglobulins consist of two identical heavy(H)chains and two identical light(L)chains that are connected by disulfide bridges to form a homodimer of heterodimers(ie.,H+ll2).Each heterodimer consists of one H chain linked with one L chain,whereas the homodimer is formed by linking two H chains *** genes for both the L and H chains are encoded by ligated gene segments that are genetically rearranged during V(D)J recombination,a process that endows each b cell with a unique receptor,giving rise to the enormous diversity of the b-cell antigen receptor repertoire.

关键词： IgA1 immunity chains