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Insect Science 2021年第1期28卷 63-76页

作者： Wen-Min Fan Dan Luo Jun-Zheng Zhang Dan Wang Jie Shen Department of Entomology and MOA Lab for Pest Monitoring and Green Control China Agricultural UniversityBeijingChina

The Decapentaplegic(dpp)and Wingless(Wg)signal pathways play important roles in numerous biological processes in Drosophila.The Drosophila vestigial(vg)gene is selectively required for wing imaginal disc cell proliferation,which is essential for the formation of the adult wing and halter structures,and is regulated by dpp and Wg signaling.Using a Drosophila invasion model of wing epithelium,we showed herein that inhibition of dpp or Wg signaling promoted cells to migrate across the cell lineage restrictive anterior/posterior(A/P)compartment boundary.Being downstream of both dpp and Wg signaling,vg can block cell migration induced by loss of either pathway.In addition,suppression of vg is sufficient to induce cell migration across the A/P boundary.Transcriptomic analysis revealed potential downstream genes involved in the cell migration after suppressing vg in the wing disc.We further demonstrated that the c-Jun N-terminal kinase(JNK)signaling promoted cell migration induced by vg suppression by upregulating Caspase activity.Taken together,our results revealed the requirement ofVg for suppressing cell migration and clarified how developmental signals collaborate to stabilize cells along the compartment boundary.

关键词： Caspase cell migration dpp Drosophila wing disc JNK vestigial Wg

Highly stable organic fluorescent nanorods for living- cell imaging

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Nano Research 2015年第7期8卷 2380-2389页

作者： Minhuan Lan Jinfeng Zhang Xiaoyue Zhu Pengfei Wang Xianfeng Chen Chun-Sing Lee Wenjun Zhang Center of Super-Diamond and Advanced Films (COSDAF) Department of Physics and Materials Science City University of Hong Kong Hong Kong SAR China Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and Chemistry (TIPC) Chinese Academy of Sciences (CAS) Beijing 100190 China These authors contributed equally to this work.

Metal-free, organic-dye-based fluorescent nanorods were fabricated through a simple solvent-exchange procedure. The as-prepared nanorods exhibit low toxicity to living cells and excellent photostability. Furthermore, they are stable in solutions of various pHs and high ionic strength and in solutions with interfering metal ions. Compared with the free dpp-Br molecules in THF, these nanorods exhibit larger Stokes shift, broader absorption spectra, and greatly improved photostability. We successfully demonstrated the application of the nanorods, including their aforementioned beneficial characteristics, as a good fluorescence probe for bio-imaging.

关键词： cell imaging organic dye, fluorescent nanorods, dpp

Two-Photon Fluorescence Properties and Ultrafast Responses of a Hyperbranched Diketo-Pyrrolo-Pyrrole Polymer with Triphenylamine as the Core

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Chinese Physics Letters 2015年第4期32卷 139-143页

作者：王耀川姜义华王桂秋刘大军李波花建丽 Department of Physics Dalian Maritime University Dalian 110626 State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116024 Lab for Advanced Materials Department of Chemistry East China University of Science and Technology Shanghai 200237 Department of Electronic Engineering East China Normal University Shanghai 200241

The two-photon fluorescence properties and ultrafast responses of a hyperbranched polyyne （hb-dpp-J2） with triphenylamine as the central core, Diketo-Pyrrolo-Pyrrole as the connecting unit and electron acceptor are studied. The polymer has a D-π-A-π-D conjugated structure along the extended polyyne w-bridge systems, and the effective condugated unit repeats itself in the whole hyperbranehed polymer chain. The polymer exhibits a large two-photon absorption cross section and high fluorescence quantum yields. The ultrafast dynamic results give a deep understanding of the excited energy transfer processes under excitation, and reveal a long relaxation lifetime of the intramolecular charge transfer （ICT） state.

关键词： dpp Two-Photon Fluorescence Properties and Ultrafast Responses of a Hyperbranched Diketo-Pyrrolo-Pyrrole Polymer with Triphenylamine as the Core THF ICT TPA

The neuroprotective effects of the anti-diabetic drug linagliptin against Aβ-induced neurotoxicity

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Neural Regeneration Research 2016年第2期11卷 236-237页

作者： Chih-Li Lin Chien-Ning Huang Institute of Medicine Chung Shan Medical University

Impaired insulin signaling in Alzheimer’s disease（AD）brains：The insulin signaling pathway is a fundamental physiological mechanism that presents in nearly all vertebrate cells.However,sometimes cells stop responding properly to insulin stimulation.This condition is known as insulin resistance,which is a hallmark of two very common conditions,metabolic syndrome and type 2 diabetes（T2D）.

关键词： GLP induced neurotoxicity dpp The neuroprotective effects of the anti-diabetic drug linagliptin against A AMPK

Sitagliptin in treatment of diabetes complicated by chronic hepatitis C

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Hepatobiliary & Pancreatic Diseases International 2010年第4期9卷 442-443页

作者： Yanai H Department of Internal Medicine Kohnodai Hospital National Center for Global Health and Medicine

To the Editor: A high prevalence of glucose intolerance in patients with chronic hepatitis C has been reported, [1] and there is a significant association of chronic hepatitis C with diabetes mellitus (DM). [2] But DM... 详细信息

关键词： dpp Sitagliptin in treatment of diabetes complicated by chronic hepatitis C

卟啉β位修饰小分子给体材料的设计合成与光伏性能的研究

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卟啉β位修饰小分子给体材料的设计合成与光伏性能的研究

作者：张雪勤华南理工大学

学位级别：硕士

化石燃料是不可再生能源,且燃烧时会产生有害气体,释放大量的二氧化碳,加剧地球的温室效应。为解决能源危机并实现可持续发展,需要在开发清洁能源方面作出巨大努力。有机太阳能电池具有质量轻、柔韧性好、可大规模加工等特点,引起各国... 详细信息

化石燃料是不可再生能源,且燃烧时会产生有害气体,释放大量的二氧化碳,加剧地球的温室效应。为解决能源危机并实现可持续发展,需要在开发清洁能源方面作出巨大努力。有机太阳能电池具有质量轻、柔韧性好、可大规模加工等特点,引起各国研究人员的广泛关注。迄今为止,使用的有机太阳能电池的结构多为体异质结型,所报道的高效器件结构亦是体异质结型。有机太阳能电池自出现之后,能量转换效率(PCEs)逐渐提高,鉴于有机太阳能电池目前发展速度且随着更多的新材料被合成和应用,器件性能将大大地改善,同时将加速实现电池应用商业化。近几年来卟啉类材料因其特殊的光化学性、平面性良好、具有12个可修饰的化学位点等性能使其在有机光伏领域占据一席之地。但与卟啉类光伏材料相关的报道数量有限,迄今为止,基于卟啉类聚合物材料的OSCs的最高能量转换效率(PCEs)为9.16%。基于小分子卟啉材料的三元OSCs的最高能量转换效率为15.88%,而基于小分子卟啉材料的二元OSCs最高为12.08%。因卟啉与dpp两者的吸收光谱是互补的且两者都是平面π结构,dpp亦是很好的吸电子单元,已报道的高效小分子卟啉类给体材料的分子结构大抵都包含dpp基团且形成A-D-A构型。但迄今为止已报道的有关卟啉类小分子光伏材料的OSCs文章所使用的卟啉材料大抵是卟啉meso位修饰材料,而关于卟啉β位修饰材料的研究仅停滞于结构上且未应用于OSCs领域。吡咯β位置上的取代基团对卟啉π体系产生的空间和电子效应,导致卟啉大环具有独特的光物理和电化学(氧化还原性)性质,且β取代的D-A/A-D-A型卟啉体系亦显示出独特的能量/电子转移性质,因此关于卟啉β位修饰的材料在OSCs领域有很大的应用空间。在第二章中,本章设计和合成了两种非对称的D-A型的小分子给体材料,于卟啉单β位上通过σ键桥连一个吸电子单元-吡咯并吡咯二酮(dpp)而合成的目标分子3,5-t Bu P-βdpp,而在卟啉单β位上通过π键桥连一个吸电子单元-吡咯并吡咯二酮(dpp)而合成的目标分子3,5-t Bu P-βEdpp,两个分子中dpp的存在不仅拓宽了分子的吸收光谱,且降低了分子的LUMO能级。本章研究内容如下:探究基于两种给体材料与Y6组成的活性层的BHJ的OSCs器件性能,OSCs器件于氯仿溶剂中蒸汽退火20 s时,基于3,5-t Bu P-βEdpp:Y6的OSCs器件的光电转化效率提高到了0.68%。研究表明π桥通过使分子内吸电子单元和给电子单元形成共轭,增强了分子内电荷转移。该研究为今后卟啉单β位D-A构型给体材料的设计及应用提供思路。在第三章中,因迄今为止高效的小分子OSCs的给体材料结构大抵是A-π-D-π-A构型,本课题设计和合成了两种非对称的A-D-A型的小分子OSCs中的给体材料3,5-t Bu P-m Edpp-βdpp和3,5-t Bu P-m Edpp-βEdpp。本章研究内容如下:首先探究σ桥和π桥对A-D-A构型给体材料吸收光谱/能级的影响;其次探究基于两种给体材料与Y6组成的活性层的BHJ的OSCs器件性能。研究表明基于3,5-t Bu P-m Edpp-βEdpp:Y6的OSCs器件的光电转换效率最高为0.89%,而基于3,5-t Bu P-m Edpp-βdpp:Y6的OSCs器件的PCE为0.22%,其次3,5-t Bu P-m Edpp-βEdpp的带隙更窄。本章研究结果表明A-π-D-π-A构型分子中β位乙炔键桥的存在提高材料的空穴迁移率,因此提高OSCs器件光电转换效率,更为将来对A-D-A型卟啉β位修饰小分子给体材料的设计提供思路和方向。在第四章中,本章设计和合成一种对称的A-D-A构型的小分子给体材料3,5-t Bu P-m Edpp-Dβdpp。本章研究内容如下:首先探究卟啉双β位分子的合成;其次探究基于3,5-t Bu P-m Edpp-Dβdpp给体材料与Y6组成的活性层的BHJ的OSCs器件性能。基于3,5-t Bu P-m Edpp-Dβdpp:Y6的OSCs器件的光电转换效率为2.34%,且比基于单β位的3,5-t Bu P-m Edpp-βEdpp:Y6的OSCs器件的光电转换效率高出2倍多。研究结果说明卟啉双β位修饰材料比卟啉单β位修饰材料的研究价值更大。本章为今后开发卟啉类光伏材料开辟了新的道路。在第五章中,本章设计和合成了两种小分子材料。本章研究内容如下:氰基罗丹宁类化合物与卟啉单β醛通过克莱森-斯密特(Claisen-Schmidt)反应,合成了通过烯键连接而成的两个化合物TC19ODPor-βERCN和TC19ODPor-βC16RCN。本章探究了卟啉单β位与吸电子单元经烯键桥连的分子的合成;其次探究氰基罗丹宁上酰胺所连不同长度的烷基链对化合物吸收和能级的影响。

关键词：小分子给体卟啉 β位 dpp

A POLAROGRAPHIC CATHODIC WAVE OF VITAMIN C

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Chinese Chemical Letters 1991年第2期2卷 185-188页

作者： Shu Bo HAN Zhuo Bin YUAN Department of Chemistry,Graduate School,USTC,Academia Sinica,Beijing 100039,P.R.China Present Address:Dept.of Environ.Eng.,Hebei Light & Chemical Institute,Shijiazhuang 050018,Hebei,P.R.C.

The cathodic wave of vitamin C has not been reported in the literature so far.Its E_(1/2)was found at-1.85 volt vs.Ag/AgCl(25℃)in the base solution of 0.1mol/L Bu_4NI.Various electrochemical and spectral techniques were used for studying the electrode reaction. They all showed that the electrode reaction was quasi-reversible while C was more than 1.0×10^(-6)mol/L and mainly adsorptive while C was less than 1.0×10^(-6)mol/L at a mercury electrode.The electron transfer number was 2 and the electron transfer coefficient 0.57. Using dpp techniques,the linear response range was 5.0×10^(-7)-2.0×10^(-3)mol/L and the detection limit 1×10^(-7)mol/L.

关键词： vitamin C dpp Polarographic cathodic wave

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苝聚集体随机激光的近场散射增强（英文）

Chinese Journal of Chemical Physics 2019年第6期32卷 739-746,I0003页

作者：张珍珍殷雷铖徐小龙夏江营谢康邹纲张晓军胡志家张其锦中国科学技术大学高分子科学与工程系中国科学技术大学化学系中国科学院软物质重点实验室安徽省光电子科学与技术重点实验室合肥230026 合肥工业大学光电子工程和仪器科学学院合肥230009 阿斯顿大学阿斯顿光子科技研究所伯明翰B47ET 西南科技大学环境友好材料国家重点实验室绵阳621000

本文通过物理模拟发现苝聚集体纳米粒子有很强的近场散射.苝聚集体由异丁基取代聚倍半硅氧烷(POSS)苝(dpp)构成,其理论模拟得到的近场散射增强被实验证实.同时,由聚集体的二硫化碳溶液激发出相干随机激光.近场增强源自于通过化学键连接... 详细信息

本文通过物理模拟发现苝聚集体纳米粒子有很强的近场散射.苝聚集体由异丁基取代聚倍半硅氧烷(POSS)苝(dpp)构成,其理论模拟得到的近场散射增强被实验证实.同时,由聚集体的二硫化碳溶液激发出相干随机激光.近场增强源自于通过化学键连接的POSS基团,相干随机激光源自于苝发射团.本文通过分子设计发展出一种新的随机激光体系,为后续一系列交叉研究打开了大门,相关交叉研究主要涵盖无序光子学的分子设计等领域.

关键词：单一粒子聚集体 dpp 近场散射增强随机激光

POLAROGRAPHIC ANALYSIS OF PYRAZINES BY PRINCIPAL COMPONENT REGRESSION

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Chinese Chemical Letters 1992年第9期3卷 721-722页

作者： Yong Nian NI Department of Chemistry,Jiangxi University,Nanehang 330047 Serge Kokot Mark Selby and Mark Hodgkinson School of Chemistry,Queensland University of Technology,Brisbane 4001 Australia

The polarograms of mixture of pyrazine and its methyl deriva- tives consist of overlapping peaks.This generally precludes the direct ana- lysis of these components without prior separation.In this paper,mixtures of pyrazines at trace level(150ppb-lppm)were analysed using differential pulse polarography(dpp)and the results were interpreted using chemometric approach:principal component regression.Acceptable results with recoveries in the 93-106% range and RSD in the ca.5-12% range were obtained.

关键词： Ni OC POLAROGRAPHIC ANALYSIS OF PYRAZINES BY PRINCIPAL COMPONENT REGRESSION MLR dpp 勺口

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STRAIT REVIEW

Beijing Review 2006年第6期49卷 22-27页

作者： AN Zl

Relations across the Taiwan Strait got off the ground last year with direct flights between the mainland and Taipei, though interaction at an official level remained turbulent. The cross-strait relationship, which continues to be an unrelenting focus of government attention, has a complicated background and unclear future, a situation echoed in recent Chinese media reports on topics relating to Taiwan. While seemingly innocuous in subject matter-charter flights, cuddly pandas- the back-story to the headl...

关键词： STRAIT REVIEW dpp PFP