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Nano Research 2016年第2期9卷 273-281页

作者： Bachir Aoun Daniela Russo Argonne National Laboratory Chicago IL 60439 USA CNR-IOM c/o Institut Laue-Langevin 38400 Grenoble France Institut Lumiere Matiere Universite de Lyon 69622 Lyon France

Molecular dynamics simulations have been used to investigate the confinement packing characteristics of small hydrophilic （N-acetyl-glycine-methylamide, Nagma） and hydrophobic （N-acetyl-leucine-methylamide, Nalma） biomolecules in large diameter single-wall carbon nanotubes （SWCNTs）. We find that hydrophilic biomolecules easily fill the nanotube and self organize into a geometrical configuration which reminds the water structural organization under SWCNT confinement. The packing of hydrophilic biomolecules inside the cylinder confines all water molecules in its core, which enhances their mobility. Conversely, hydrophobic biomolecules accommodate into the nanotubes with a trend for homogeneous filling, which generate unstable small pockets of water and drive toward a state of dehydration. These results shed light on key parameters important for the encapsulation of biomolecules with direct relevance for long-term storage and prevention of degradation.

关键词： nano-confinement protein folding hydration water carbon nanotube drug delivery

Synthesis of Branched Poly(butylene succinate):Structure Properties Relationship

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Chinese Journal of Polymer Science 2016年第7期34卷 873-888页

作者： Marie Vandesteene Nicolas Jacquel Rene Saint-Loup Nadège Boucard Christian Carrot Alain Rousseau Francoise Fenouillot Unive Lyon INSA-LyonIngenierie des Materiaux PolymeresIMPUMR5223F-69621VilleurbanneFrance Univ Lyon Universite Jean MonnetIngenierie des Materiaux PolymeresIMPUMR5223F-42023 Saint-EtienneFrance Roquette Freres.Polymer Chemistry Department F-62136 LestremFrance MBD Texinov F-38110 Saint-Didier-de-la-TourFrance

A series of branched poly（butylene succinate）（PBS） were synthesized with several branching agents namely trimethylol propane（TMP）, malic acid, trimesic acid, citric acid and glycerol propoxylate. The structure of the branched polymers was analyzed by SEC and ~1H-NMR. The effect of branching agent structure on crystallization was also investigated and played a significant role. Isothermal studies showed that glycerol propoxylate could act as a nucleating agent. By contrast high content of TMP disturbed the regularity of the chain and hindered the crystallization of PBS. From the non-isothermal kinetic study, it was found that glycerol propoxylate increased noticeably the crystallization rate due to the flexible structure of the branching agent. A secondary nucleation was observed with glycerol propoxylate attributed to the crystallization of amorphous fraction included between crystallites formed at the primary crystallization. Chain topology was obtained through rheological investigations and the synthesized polymers showed a typical behavior of a mixture of linear and randomly branched PBS. The incorporation of branches improved the processability of PBS for film blowing application and the modulus and the stress at break of the resulting film were significantly increased.

关键词： Poly(butylene succinate) Branching Crystallization Properties

Synthesis of(±)-phthalascidin 622

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Science China Chemistry 2010年第9期53卷 1888-1898页

作者： CHRISTIAN R.Razafindrabe SYLVAIN Aubry BENJAMIN Bourdon MARTA Andriantsiferana STEPHANE Pellet-Rostaing MARC Lemaire Laboratoire de Chimie des Produits Naturels et Biotechnologie(LPNB) Université d'Antananarivo17 Cité Mahatazana-Ampandrianomby101 Antananarivo ICBMS Institut de Chimie et Biochimie Moléculaires et SupramoléculairesCNRSUMR5246Laboratoire de Catalyse et Synthèse Organique ICSM institut de Chimie Séparative de MarcouleCNRS/CEA/UM2/ENSCMUMR 5257Laboratoire de Tri Ionique par des Systèmes Moléculaires auto-assemblés

A synthesis of functionalized phenolic α-amino-alcohols(±)-8 and(±)-16 as synthetic precursors of the catechol tetrahydroisoquinoline structure of phthalascidin 650 was disclosed.(±)-8 was prepared in 5 steps from the commercially available *** from 3-methyl catechol 5,8 steps gave rise to the synthesis of phenolic α-amino-alcohol(±)-16 in 27% overall *** synthetic strategy involved the elaboration of fully functionalized aromatic aldehyde 13 and its transformation into a phenolic α-amino-alcohol(±)-16,through a Knoevenagel condensation,simultaneous reduction of nitroketene and ester functions,and hydrogenolysis of the benzyl protecting *** pentacycle(±)-4 was obtained after 4 additional *** Pictet-Spengler cyclisation between the phenolic α-amino-alcohol(±)-16 and the N-protected α-amino-aldehyde 4 allowed to obtain(1,3')-bis-tetrahydroisoquinoline 17 with N-methylated and N-Fmoc *** last step was a Swern oxidation allowing the expected intramolecular condensation.

关键词： phthalascidin ecteinascidin (1 3’)-bis-tetrahydroisoquinoline Pictet-Spengler Bishler-Napieralsky

Homogeneous Plastic Flow of Fully Amorphous and Partially Crystallized Zr_(41.2)Ti_(13.8)Cu_(12.5)Ni_(10)Be_(22.5) Bulk Metallic Glass

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Journal of Materials Science & Technology 2003年第6期19卷 557-560页

作者： Q.WANG J.J.Blandin M.Suery B.Van de Moortele J.M.Pelletier GPM2 ENSPG D.U. B.P.46 38042 Grenoble France Institute of Materials Shanghai University Shanghai 200072 ChinaGPM2 ENSPG D.U. B.P.46 38042 Grenoble FranceGPM2 ENSPG D.U. B.P.46 38042 Grenoble FranceGEMPPM Bat. B. PascalINSA 69621 Villeurbanne Cedex FranceGEMPPM Bat. B. PascalINSA 69621 Villeurbanne Cedex France

The homogeneous plastic flow of fully amorphous and partially crystallized Zr(41.2)Ti(13.8)Cu(12.5)Ni(10)Be(22.5) bulk metallic glass (Vitl) has been investigated by compression tests at high temperatures in supercooled liquid region. Experimental results show that at sufficiently low strain rates, the supercooled liquid of the fully amorphous alloy reveals Newtonian flow with a linear relationship between the flow stress and strain rate. As the strain rate is increased, a transition from linear Newtonian to nonlinear flow is detected, which can be explained by the transition state theory. Over the entire strain rate interval investigated, however, only nonlinear flow is present in the partially crystallized alloy, and the flow stress for each strain rate is much higher. It is found that the strain rate-stress relationship for the partially crystaltized alloy at the given temperature of 646 K also obeys the sinh law derived from the transition state theory, similar to that of the initial homogeneous amorphous alloy. Thus, it is proposed that the flow behavior of the nanocrystalline/amorphous composite at 646 K is mainly controlled by the viscous flow of the remaining supercooled liquid.

关键词： Homogeneous plastic flow Zr41.2Ti13.8Cu12.5Ni10Be22.5 amorphous alloy,Partially crystallized amorphous alloy

Explosive synchronization enhances selectivity： Example of the cochlea

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Frontiers of physics 2017年第5期12卷 241-249页

作者： Chao-Qing Wang Alain Pumir Nicolas B. Garnier Zong-Hua Liu Department of Physics East China Normal University Shanghai 200241 China Laboratoire de Physique de I'ENS de Lyon CNRS UMR 5672 46 Allde d'Italie F-69364 Lyon France

Acoustical signal transduction in the cochlea is an active process that involves nonlinear amplification and spontaneous otoacoustic emissions. Signal transduction involves individual subunits composed of globally coupled hair cells, which can be modeled as oscillators close to a Hopf bifurcation. The coupling may induce a transition toward synchronization, which in turn leads to a strong nonlinear response. In the model studied here, the synchronization transition of the subunit is discontinuous （explosive） in the absence of an external stimulus. We show that, in the presence of an external stimulus and for a coupling strength slightly lower than the critical value leading to explosive synchronization, the response of the subunit has better frequency selectivity and a larger signal-to-noise ratio. From physiological observations that subunits are themselves coupled together, we further propose a model of the complete cochlea, accounting for the ensemble of frequencies that the organ is able to detect.

关键词： cochlea frequency selectivity periodical forcing explosive synchronization

Enhancement of anaerobic biodegradability of flower stem wastes with vegetable wastes by co-hydrolysis

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Journal of Environmental Sciences 2008年第3期20卷 297-303页

作者： ZHANG Bo HE Pinjing Lü Fan SHAO Liming State Key Laboratory of Pollution Control and Resources Reuse Key Laboratory of Yangtze River Water Environment College of Environmental Science and Engineering Tongfi University Shanghai 200092 China

The vegetable wastes and flower stems were co-digested to evaluate the anaerobic hydrolysis performance of difficultly biodegradable organic wastes by introducing readily biodegradable organic wastes. The experiments were carried out in batches. When the vegetable wastes were mixed with the flower stems at the dry weight ratio of 1 to 13, the overall hydrolysis rate increased by 8%, 12%, and 2% according to the carbon, nitrogen, and total solid （TS） conversion rate, respectively. While the dry weight ratio was designed as 1 to 3, there was a respective rise of 5%, 15%, and 4% in the conversion rate of carbon, nitrogen, and TS. The enhancement of anaerobic hydrolysis from the mixed vegetable wastes and flower stems can be attributed to the formation of volatile fatty acids （VFA） and nutrient supplement like nitrogen content. The maximum VFA concentration can achieve 1.7 g/L owing to the rapid acidification of vegetable wastes, loosing the structure of lignocellulose materials. The statistic bivariate analysis revealed that the hydrolysis performance was significantly related to the physical and biochemical compositions of the feeding substrate. Especially, the soluble carbon concentration in the liquid was significantly positively correlated to the concentration of nitrogen and hemicellulose, and negatively correlated to the concentration of carbon and lignocellulose in the feeding substrate, suggesting that the regulation and control of feedstock can have an important influence on the anaerobic hydrolysis of organic wastes.

关键词： municipal solid wastes hydrolysis feedstock characteristics VFA bivariate analysis

Elliptical Splats Based Isosurface Visualization for Volume Data

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Journal of Shanghai Jiaotong university(Science) 2008年第5期13卷 533-537页

作者：秦红星石峰郭律杨杰 Institute of Image Processing & Pattern Recognition Shanghai Jiaotong University

Elliptical splats are used to represent and render the isosurface of volume data. The method consists of two steps. The first step is to extract points on the isosurface by looking up the case table. In the second step, properties of splats are computed based on local geometry. Rendering is achieved using surface splatting algorithm. The obtained results show that the extraction time of isosurfaces can be reduced by a factor of three. So our approach is more appropriate for interactive visualization of large medical data than the classical marching cubes (MC) technique.

关键词： volume visualization elliptical splats isosurface extraction differential geometry

Responses of five woody species to burial by marly sediment: the role of biomass allocation pattern flexibility

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Journal of Plant Ecology 2012年第3期5卷 287-293页

作者： M.Burylo F.Rey T.Dutoit Cemagref Grenoble UR Ecosystemes Montagnards2 rue de la PapeterieBP 7638402 Saint Martin d’Heres CedexFrance Institut Mediterraneen d’Ecologie et de Paleoecologie Unite Mixte de Recherches CNRS-IRDInstitut Universitaire deTechnologieUniversite d’AvignonAgroparcBP 120784911 Avignon Cedex 9France

Aims In eroded lands of the French Southern Alps,burial of early established seedlings under marly sediment weakens the effect of vegetation on soil stabilization and sediment ***,this protective role is largely dependent on species’resistance to burial,and the understanding of species’tolerance to this environmental disturbance is highly valuable for basic knowledge on plant succession and for ecological restoration *** The response of five woody species with contrasting ecological requirements and natural habitats—three tree species,Pinus nigra,Robinia pseudoacacia and Acer campestre,and two shrubs,Ononis fruticosa and Hippophae rhamnoides—to experimental burial under marly sediment was *** were exposed to three burial levels:no burial(control),partial burial(50%of seedling height)and complete burial(100%of seedling height).Burial tolerance was evaluated based on seedling survival,height and *** allocation to shoots and roots and soluble sugar and starch contents in roots and stems were measured to identify plant traits that determine species response to *** Findings All species survived partial burial but only *** seedlings emerged from complete *** species were more tolerant to burial and buried plants showed no significant differences with *** two shrubs were found less tolerant and buried plants showed slower growth than *** results showed that species response was not related to initial soluble and starch content in roots and stems,but instead to biomass allocation pattern flexibility.

关键词： burial sediment marls response to burial plant traits

Nano-fried-eggs： Structural, optical, and magnetic characterization of physically prepared iron-silver nanoparticles

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Nano Research 2018年第11期11卷 6074-6085页

作者： Julien Ramade Nicolas Troc Olivier Boisron Michel Pellarin Marie-Ange Lebault Emmanuel Cottancin Vitor T. A. Oiko Rafael Cabreira Gomes Varlei Rodrigues Matthias Hillenkamp Univ. Lyon Universitd Claude Bernard Lyon I CNRS UMR5306 Institut Lumiee Matiee t=-69622 Villeurbanne France Instituto de F[sica Gleb Wataghin UNICAMP CP 6165 13083-970 Campinas SP Brazil

The prospect of combining both magnetic and plasmonic properties in a single nanoparticle promises both valuable insights on the properties of such systems from a fundamental viewpoint and numerous possibilities for technological applications. However, the combination of two of the most prominent metallic candidates—iron and silver—has presented numerous experimental difficulties because their thermodynamic properties impede miscibility and even coalescence. Herein, we present the thorough characterization of physically prepared Fe50Ag50 nanoparticles embedded in carbon and silica matrices via electron microscopy, optical spectroscopy, magnetometry and synchrotron-based X-ray spectroscopy. Iron and silver segregate completely into structures resembling fried eggs, with a nearly spherical, crystallized silver part surrounded by an amorphous structure of iron carbide or oxide, depending on the environment of the particles. Consequently, the particles exhibit both plasmonic absorption corresponding to the silver nanospheres in an oxide environment and a reduced but measurable magnetic response. The suitability of such nanoparticles for technological applications is discussed from the viewpoint of their high chemical reactivity with their environment.

关键词： nanoalloy bimetallic nanoparticles iron silver FeAg optical spectroscopy magnetometry

Measles virus hemagglutinin triggers intracellular signaling in CD150-expressing dendritic cells and inhibits immune response

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Cellular & Molecular Immunology 2016年第6期13卷 828-838页

作者： Olga Romanets-Korbut Larysa M. Kovalevska Tsukasa Seya Svetlana P. Sidorenko Branka Horvat CIRI International Center for Infectiology Research IblVteam Universite de Lyon Lyon France Inserm U1111 Lyon France CNRS UMR5308 Lyon France Universite Lyon 1 Lyon France Ecole Normale Superieure de Lyon Lyon France R.E. Kavetsky Institute of Experimental Pathology Oncology and Radiobiology NASU Kyiv Ukraine and 7Department of Microbiology and Immunology Graduate School of Medicine Hokkaido University Kita-ku Sapporo Japan Department ofMicrobiologyand Immunology Graduate School of Medicine Hokkaido University Kita-kuSapporo Japan

Measles virus （MV） is highly contagious pathogen, which causes a profound immunosuppression, resulting in high infant mortality. This virus infects dendritic cells （DCs） following the binding of MV hemagglutinin （MV-H） to CD150 receptor and alters DC functions by a mechanism that is not completely understood. We have analyzed the effect of MV-H interaction with CD150-expressing DCs on the DC signaling pathways and consequent phenotypic and functional changes in the absence of infectious context. We demonstrated that contact between CD150 on human DCs and MV-H expressed on membrane of transfected CHO cells was sufficient to modulate the activity of two major regulatory pathways of DC differentiation and function： to stimulate Akt and inhibit p38 MAPK phosphorylation, without concomitant ERK1/2 activation. Furthermore, interaction with MV-H decreased the expression level of DC activation markers CD80, CD83, CD86, and HLA-DR and strongly downregulated IL-12 production but did not modulate IL-IO secretion. Moreover, contact with MV-H suppressed DC-mediated T-cell alloproliferation, demonstrating profound alteration of DC maturation and functions. Finally, engagement of CD150 by MV-H in mice transgenic for human CD150 decreased inflammatory responses, showing the immunosuppressive effect of CD150-MV-H interaction in vivo. Altogether, these results uncover novel mechanism of MV-induced immunosuppression, implicating modulation of cell signaling pathways following MV-H interaction with CD150-expressing DCs and reveal anti-inflammatory effects of CD150 stimulation.

关键词： dendritic cells measles virus signaling pathways SLAM/CD150