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Propagation of kink–antikink pair along microtubules as a control mechanism for polymerization and depolymerization processes

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Chinese Physics B 2014年第9期23卷 556-570页

作者： L.Kavitha A.Muniyappan S.Zdravkovi M.v.Satari A.Marlewski S.Dhamayanthi D.Gopi Department of Physics School of Basic and Applied SciencesCentral University of Tamilnadu (CUTN) The Abdus Salam International Center for Theoretical Physics Department of Physics Periyar University Institut za nuklearne nauke vinca Laboratorija za atomsku fiziku 040Univerzitet u Beogradu Fakultet tehnickih nauka Univerzitet u Novom Sadu Institute of Mathematics Poznan University of Technology Center for Nanoscience and Nanotechnology Periyar University Department of Chemistry Periyar University

Among many types of proteinaceous filaments, microtubules （MTs） constitute the most rigid components of the cellular cytoskeleton. Microtubule dynamics is essential for many vital cellular processes such as intracellular transport, metabolism, and cell division. We investigate the nonlinear dynamics of inhomogeneous microtubulin systems and the MT dynamics is found to be governed by a perturbed sine-Gordon equation. In the presence of various competing nonlinear inhomogeneities, it is shown that this nonlinear model can lead to the existence of kink and antikink solitons moving along MTs. We demonstrate kink-antikink pair collision in the framework of Hirota＇s bilinearization method. We conjecture that the collisions of the quanta of energy propagating in the form of kinks and antikinks may offer a new view of the mechanism of the retrograde and anterograde transport direction regulation of motor proteins in microtubulin systems.

关键词： microtubules solitons solitary solutions partial differential equations

应用本构模型和神经网络模型预测铝/镁基纳米复合材料的高温流变行为(英文)

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中国有色金属学会会刊：英文版 2013年第6期23卷 1737-1750页

作者： v.SENTHILKUMAR A.BALAJI D.ARULKIRUBAKARAN Department of Production Engineering National Institute of Technology

为了预测Al/Mg基纳米复合材料的高温流变行为,在不同的应变速率(0.01-1.0s-)和温度(523,623和1723K)的条件下进行热压缩试验,利用所得到的应力-应变数据,开发了本构模型,比如一般流动方程。阿累尼乌斯双曲模型、Johnson-Cook(JC)和改性... 详细信息

为了预测Al/Mg基纳米复合材料的高温流变行为,在不同的应变速率(0.01-1.0s-)和温度(523,623和1723K)的条件下进行热压缩试验,利用所得到的应力-应变数据,开发了本构模型,比如一般流动方程。阿累尼乌斯双曲模型、Johnson-Cook(JC)和改性的Zerilli-Armstrong(za)模型及人工神经网络(ANN)模型。通过使用统计参数,例如均方根误差(RMSE)、回归系数(R2)、平均相对误差(MRE)和分散指数(Is),比较了人工神经网络和不同的本构模型。结果表明,人工神经网络模型对AA5083-2%TiC复合材料的热变形流动应力的评估准确性更高。

关键词：热压缩 Johnson-Cook(JC)模型改性Zerilli-Armstrong(za)模型阿累尼乌斯(AR)双曲模型流动应力纳米复合材料

有机胺盐酸盐/B(C_6F_5)_3催化的酸与炔烃选择性加成反应研究

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化学学报 2016年第6期74卷 498-502页

作者：温志国田冲 Borzov Maxim v. 聂万丽天然产物与小分子合成四川省高校重点实验室乐山师范学院化学学院四川乐山614000

一直以来寻找直接有效的乙烯基官能化合成方法的研究备受关注.报道了一种新型的有机胺盐酸盐/B(C_6F_5)_3(BCF)体系催化炔烃与氢氯酸或羧酸的加成反应方法,可选择性地在炔烃的C(2)位氯代或羧化.研究了在有机胺盐酸盐/BCF体系催化下,不... 详细信息

一直以来寻找直接有效的乙烯基官能化合成方法的研究备受关注.报道了一种新型的有机胺盐酸盐/B(C_6F_5)_3(BCF)体系催化炔烃与氢氯酸或羧酸的加成反应方法,可选择性地在炔烃的C(2)位氯代或羧化.研究了在有机胺盐酸盐/BCF体系催化下,不同取代的炔烃与无机酸HCl的氢氯化加成反应.在2,2,4,4-四甲基哌啶盐酸盐/BCF([TMPH]+[Cl-B(C_6F_5)_3]-)催化下,等物质的量的炔烃和HCl反应时,端基芳炔的C(2)位一加成产物的比例可高达90%以上,而端基烷基炔烃的选择性较芳炔差,叔丁基乙炔的一加成产物只占到67%.报道了非金属催化剂路易斯酸BCF催化的炔烃与羧酸CF_3COOH的烯醇酯化反应,端基芳炔的C(2)位烯醇酯化产率可达95%以上,而二苯基乙炔及非芳香性端基炔的反应活性较低.首次实现了非金属催化剂FLPs参与催化的炔烃与酸的选择性氢氯化和烯醇酯化加成反应.

关键词：受限路易斯酸碱对有机胺盐酸盐酸炔烃加成反应

Optical studies of Y3（Al,Ga）5O12:Ce3+,Cr3+,Nd3+ nano-phosphors obtained by the Pechini method

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Journal of Rare Earths 2019年第11期37卷 1132-1136页

作者： Z.Dai v.Boiko M.Markowska A.Gerus K.Grzeszkiewicz J.Holsa M.L.Saladino D.Hreniak Institute of Low Temperature and Structure Research Polish Academy of SciencesOkolna 2.PL-50-422 WroctawPoland Department of Physics University of the Free StateBloemfontein ZA-9300South Africa Department of Biological Chemical and Pharmaceutical Sciences and Technologies(STEBICEF)University of PalermoViale delle ScienzeBld.171-90128 PalermoItaly

The Y3(AI,Ga)5O12:Ce^3+,Cr^3+,Nd^3+(YAGG)nano-phosphors with homogeneous particle-size distribution,low aggregation and average crystalline size of about 65 nm were obtained using a modified Pechini *** slight aggregation of the crystallites occurs after post-annealing at 1100℃.The intense Ce^3+bands in the excitation spectra of the Ce^3+,Cr^3+,Nd^3+co-doped materials monitoring the Cr^3+emission at 690 nm indicate energy transfer from Ce^3+to Cr^3+.Weak Nd^3+lines are observed,as *** addition,the emission of Nd^3+at 1060 nm with excitation of Ce^3+and Cr^3+confirms the Ce^3+/Cr^3+to Nd^3+energy *** short average luminescence decay times for the Ce^3+emission indicate the Ce^3+/Cr^3+to Nd^3+energy ***,the Y3(AI,Ga)5O12:Ce^3+,Cr^3+,Nd^3+nano-phosphors exhibit persistent luminescence originating from the 4f^3→4f^3 transitions of Nd^3+which matches well to the first biological window to be used in bioimaging applications.

关键词： Nano-phosphors Ce^3+ NIR persistent luminescence Thermoluminescence Rare earths

The spectrum of building block conformers sustains the biophysical properties of clinically-oriented self-assembling protein nanoparticles

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Science China Materials 2022年第6期65卷 1662-1670页

作者： Eric voltà-Durán Julieta M Sánchez Hèctor-López-Laguna Eloi Parladé Laura Sánchez-García Alejandro Sánchez-Chardi Ario de Marco Ugutz Unzueta Esther vázquez Antonio villaverde Institut de Biotecnologia i de Biomedicina Universitat Autònoma de BarcelonaBellaterra 08193BarcelonaSpain Departament de Genètica i de Microbiologia Universitat Autònoma de BarcelonaBellaterra 08193BarcelonaSpain CIBER de Bioingeniería Biomateriales y Nanomedicina(CIBER-BBN) Bellaterra 08193BarcelonaSpain Instituto de Investigaciones Biológicas y Tecnológicas(IIBYT)(CONICET-Universidad Nacional de Córdoba) ICTA&Cátedra de Química BiológicaDepartamento de QuímicaFCEFyNUNC.Av.Velez Sarsfield 1611X 5016GCA CórdobaArgentina Servei de Microscòpia Universitat Autònoma de BarcelonaBellaterra 08193BarcelonaSpain Departament de Biologia Evolutiva Ecologia i Ciències AmbientalsFacultat de BiologiaUniversitat de Barcelona08028 BarcelonaSpain Laboratory for Environmental and Life Sciences University of Nova GoricaNova Gorica 5000Slovenia Biomedical Research Institute Sant Pau(IIB Sant Pau) Sant Antoni Ma Claret 16708025 BarcelonaSpain

Histidine-rich peptides confer self-assembling properties to recombinant proteins through the supramolecular coordination with divalent *** fact allows the cost-effective,large-scale generation of microscopic and macroscopic protein materials with intriguing biomedical *** such materials,resulting from the simple bioproduction of protein building blocks,homomeric nanoparticles are of special value as multivalent interactors and drug ***,we have here identified that the assembly of a given His-tagged protein might render distinguishable categories of self-assembling protein *** fact has been scrutinized through the nanobody-containing fusion proteins EM1-GFP-H6 and A3C8-GFP-H6,whose biosynthesis results in two distinguishable populations of building *** one of them,the assembling and disassembling is controllable by ***,a second population immediately self-assembles upon purification through a non-regulatable pathway,rendering larger nanoparticles with specific biological *** structural analyses of both model proteins and nanoparticles revealed important conformational variability in the building *** fact renders different structural and functional categories of the final soft materials resulting from the participation of energetically unstable intermediates in the oligomerization *** data illustrate the complexity of the Hismediated protein assembling in recombinant proteins but they also offer clues for a better design and refinement of protein-based nanomedicines,which,resulting from biological fabrication,show an architectonic flexibility unusual among biomaterials.

关键词： recombinant proteins self-assembling protein materials nanoparticles biomaterials

家兔主动脉粥样斑块内血管内皮生长因子表达与煦少火胶囊的干预

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中国组织工程研究与临床康复 2007年第49期11卷 9863-9867页

作者：武密山范淑萍赵素芝白霞姜志安李志英河北医科大学中医学院方剂教研室河北省石家庄市050091 河北省人民医院妇产科河北省石家庄市050031 石家庄市桥东区医院河北省石家庄市050041 河北医科大学第三医院心血管科河北省石家庄市050051 河北医科大学河北省石家庄市050091

目的:根据《素问·阴阳应象大论》"少火之气壮"的理论研制的"煦少火"复方中药在冠心病的治疗中虽取得较好的效果,但其作用途径需深入探讨。实验观察了其对家兔动脉粥样斑块血管内皮生长因子表达的影响,以验证作用机制。方法:实验于2005-... 详细信息

目的:根据《素问·阴阳应象大论》"少火之气壮"的理论研制的"煦少火"复方中药在冠心病的治疗中虽取得较好的效果,但其作用途径需深入探讨。实验观察了其对家兔动脉粥样斑块血管内皮生长因子表达的影响,以验证作用机制。方法:实验于2005-01/2007-05在河北医科大学中西医结合基础实验室完成。①材料:清洁级健康新西兰纯种雄性大白兔64只,体质量(2.5±0.5)kg;煦少火胶囊(由附子、西洋参、石菖蒲、丹参、枳壳等组成);通心络胶囊(石家庄以岭药业股份有限公司),辛伐他汀(北京万生药业有限公司)。②分组:将兔随机分成5组:空白对照组、高脂造模组、辛伐他汀组、通心络组、煦少火胶囊组,每组各12只。③给药:空白对照组喂正常饲料,其余各组均喂高脂肪饲料8周,构建实验性家兔主动脉粥样硬化模型。辛伐他汀组喂服辛伐他汀药液[2.5mg/(kg·d)];通心络组喂服通心络药液[1.0g/(kg·d)];煦少火胶囊组喂服煦少火药液[1.0g/(kg·d)],继续喂养4周。④评估:观察各组血清低密度脂蛋白胆固醇,一氧化氮,乳酸脱氢酶及血管形态学的变化;采用免疫组织化学,反转录聚合酶链式反应及WesternBlot蛋白印迹方法,从不同水平观察煦少火胶囊、通心络及辛伐他汀对动脉粥样斑块血管内皮生长因子表达的影响。结果:4只兔验证模型是否成功。60只家兔进入结果分析。①与空白对照组比较,高脂模型组的血清总胆固醇、三酰甘油、低密度脂蛋白胆固醇增高,高密度脂蛋白胆固醇降低(均P0.01);血清乳酸脱氢酶增高,一氧化氮降低(均P0.01);光镜下观察家兔整条主动脉内膜粗糙不平,有大量粥样硬化斑块形成;血管内皮生长因子免疫组织化学染色为强阳性表达(P0.01),反转录-聚合酶链反应分析呈现强亮度条带(P0.05),Westernblot蛋白印迹分析增高(P0.01)。②与高脂模型组比较,煦少火组、通心络组、辛伐他汀组的血清总胆固醇、三酰甘油、低密度脂蛋白胆固醇降低,(均P0.01);血清乳酸脱氢酶降低,一氧化氮升高(均P0.01);主动脉内膜粥样硬化斑块较少、程度轻,主要限于主动脉弓段和分叉处(P0.01);血管内皮生长因子免疫组织化学染色为弱阳性表达(P0.01),反转录-聚合酶链反应分析可见模糊条带;Western blot蛋白印迹分析降低(均P0.01)。结论:"煦少火胶囊"减少动脉粥样斑块血管内皮生长因子表达,降低血清低密度脂蛋白胆固醇及乳酸脱氢酶的浓度,升高一氧化氮浓度;其可通过降低血管内皮生长因子在粥样斑块中的表达,实现稳定粥样斑块,延缓动脉粥样硬化进程的作用。

关键词：血管内皮生长因子类动脉硬化内皮中药疗法组织构建

Studies of laser-plasma interaction physics with low-density targets for direct-drive inertial confinement schemes

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Matter and Radiation at Extremes 2019年第4期4卷 15-22页

作者： v.Tikhonchuk Y.J.Gu O.Klimo J.Limpouch S.Weber ELI-Beamlines Institute of PhysicsAcademy of Sciences of the Czech Republic18221 PragueCzech Republic Centre Lasers Intenses et Applications University of Bordeaux–CNRS–CEATalence 33405France Institute of Plasma Physics of the CAS Za Slovankou 1782/318200 PragueCzech Republic FNSPE Czech Technical University in Prague11519 PragueCzech Republic

Comprehensive understanding and possible control of parametric instabilities in the context of inertial confinement fusion (ICF) remains achallenging task. The details of the absorption processes and the detrimental effects of hot electrons on the implosion process require as mucheffort on the experimental side as on the theoretical and simulation side. This paper describes a proposal for experimental studies on nonlinearinteraction of intense laser pulses with a high-temperature plasma under conditions corresponding to direct-drive ICF schemes. We propose todevelop a platform for laser-plasma interaction studies based on foam targets. Parametric instabilities are sensitive to the bulk plasma temperatureand the density scale length. Foam targets are sufficiently flexible to allow control of these parameters. However, investigationsconducted on small laser facilities cannot be extrapolated in a reliable way to real fusion conditions. It is therefore necessary to performexperiments at a multi-kilojoule energy level on medium-scale facilities such asOMEGAor SG-III. An example of two-plasmon decay instabilityexcited in the interaction of two laser beams is considered.

关键词： interaction details excited

Collective absorption of laser radiation in plasma at sub-relativistic intensities

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High Power Laser Science and Engineering 2019年第3期7卷 27-36页

作者： Y.J.Gu O.Klimo Ph.Nicolai S.Shekhanov S.Weber v.T.Tikhonchuk ELI-Beamlines Institute of PhysicsCzech Academy of Sciences25241 Dolni BrezanyCzech Republic Institute of Plasma Physics of the CAS Za Slovankou 1782/318200 PragueCzech Republic Faculty of Nuclear Sciences and Physical Engineering Czech Technical University in Prague11519 PragueCzech Republic Centre of Intense Lasers and Applications University of BordeauxCNRSCEA33405 TalenceFrance School of Science Xi'an Jiaotong UniversityXi'an 710049China

Processes of laser energy absorption and electron heating in an expanding plasma in the range of irradiances Iλ^2=1015–1016 W·μm^2/cm^2 are studied with the aid of kinetic *** results show a strong reflection due to stimulated Brillouin scattering and a significant collisionless absorption related to stimulated Raman scattering near and below the quarter critical *** presented are parametric decay instability and resonant excitation of plasma waves near the critical *** these processes result in the excitation of high-amplitude electron plasma waves and electron *** spectrum of scattered radiation is significantly modified by secondary parametric processes,which provide information on the spatial localization of nonlinear absorption and hot electron *** considered domain of laser and plasma parameters is relevant for the shock ignition scheme of inertial confinement fusion.

关键词： inertial confinement fusion parametric instabilities

Near-infrared fluorescence sentinel lymph node detection in gastric cancer: A pilot study

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World Journal of Gastroenterology 2016年第13期22卷 3644-3651页

作者： Quirijn RJG Tummers Leonora SF Boogerd Wobbe O de Steur Floris PR verbeek Martin C Boonstra Henricus JM Handgraaf John v Frangioni Cornelis JH van de velde Henk H Hartgrink Alexander L vahrmeijer Department of Surgery Leiden University Medical Center 2333 ZA Leiden The Netherlands Division of Hematology/Oncology Department of Medicine and Department of Radiology Beth Israel Deaconess Medical Center Boston MA 02215 United States Curadel LLC 377 Plantation Street Worcester MA 01605 United States

AIM: To investigate feasibility and accuracy of near-infrared fluorescence imaging using indocyanine green: nanocolloid for sentinel lymph node (SLN) detection in gastric ***: A prospective, single-institution, phase I feasibility trial was conducted. Patients suffering from gastric cancer and planned for gastrectomy were included. During surgery, a subserosal injection of 1.6 mL ICG:Nanocoll was administered around the tumor. NIR fluorescence imaging of the abdominal cavity was performed using the Mini-FLARE™ NIR fluorescence imaging system. Lymphatic pathways and SLNs were visualized. Of every detected SLN, the corresponding lymph node station, signal-to-background ratio and histopathological diagnosis was determined. Patients underwent standard-of-care gastrectomy. Detected SLNs outside the standard dissection planes were also resected and ***: Twenty-six patients were enrolled. Four patients were excluded because distant metastases were found during surgery or due to technical failure of the injection. In 21 of the remaining 22 patients, at least 1 SLN was detected by NIR Fluorescence imaging (mean 3.1 SLNs; range 1-6). In 8 of the 21 patients, tumor-positive LNs were found. Overall accuracy of the technique was 90% (70%-99%; 95%CI), which decreased by higher pT-stage (100%, 100%, 100%, 90%, 0% for respectively Tx, T1, T2, T3, T4 tumors). All NIR-negative SLNs were completely effaced by tumor. Mean fluorescence signal-to-background ratio of SLNs was 4.4 (range 1.4-19.8). In 8 of the 21 patients, SLNs outside the standard resection plane were identified, that contained malignant cells in 2 ***: This study shows successful use of ICG:Nanocoll as lymphatic tracer for SLN detection in gastric cancer. Moreover, tumor-containing LNs outside the standard dissection planes were identified.

关键词： Gastric cancer Sentinel lymph node Near-infrared fluorescence imaging Image-guided surgery Indocyanine green