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Increase in the Hydrophilicity and Lewis Acid-Base Properties of Solid Surfaces Achieved by Electric Gliding Discharge in Humid Air: Effects on Bacterial Adherence

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Plasma Science and Technology 2009年第2期11卷 187-193页

作者： J.O.KAMGANG M.NAITALI J.-M.HERRY M.-N.BELLON-FONTAINE J.-L.BRISSET R.BRIANDET Laboratory of Interfacial Electrochemistry and Analytical Chemistry University of Rouen INRA(National Institute for Agricultural Research) UMR 763 Bio-adhesion and Hygiene of Materials AgroParisTech UMR 763 Bio-adhesion and Hygiene of Materials AgroParisTech UMR763 Bio-adhesion and Hygiene of Materials

This study addressed the effects of treatment with gliding discharge plasma on the surface properties of solid materials, as well as the consequences concerning adherence of a model bacterium. As evaluated by contact angles with selected liquids, plasma treatment caused an increase in surface hydrophilicity and in the Lewis acid-base components of the surface energy of all materials tested. These modifications were more marked for low density polyethylene and stainless steel than for polytetrafiuoroethylene. After treatment, the hydrophilicity of the materials remained relatively stable for at least 20 days. Moreover, analysis of the topography of the materials by atomic force microscopy revealed that the roughness of both polymers was reduced by glidarc plasma treatment. As a result of all these modifications, solid substrates were activated towards micro-organisms and the adherence of S. epidermidis, a negatively charged Lewis-base and mildly hydrophilic strain selected as the model, was increased in almost all the cases tested.

关键词： gliding arc plasma surface energy properties polymers stainless steel surface hydrophilicity atomic force microscopy

Molecular Simulations using Spherical Harmonics

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Chinese Journal of Chemistry 2003年第10期21卷 1252-1255页

作者：蔡文生徐佳维邵学广 MAIGRET Bernard Department of Chemistry umr 7565 CNRS/UHP

Computer aided drug design is to develop a chemical that binds to a target macromolecule known to play a key role in a disease state. In recognition of ligands by their protein receptors, molecular surfaces are often used because they represent the interacting part of molecules and they should reflex the complementarity between ligand and receptor. However, assessing the surface complementarity by searching all relative position of two surfaces is often computationally expensive. The complementarity of lobe hole is very important in protein ligand interactions. Spherical harmonic models based on expansions of spherical harmonic functions were used as a fingerprint to approximate the binding cavity and the ligand, respectively. This defines a new way to identify the complementarity between lobes and holes. The advantage of this method is that two spherical harmonic surfaces to be compared can be defined separately. This method can be used as a filter to eliminate candidates among a large number of conformations, and it will speed up the docking procedure. Therefore, it is possible to select complementary ligands or complementary conformations of a ligand and the macromolecules, by comparing their fingerprints previously stored in a database.

关键词： molecular surface shape complementarity molecular docking molecular recognition spherical harmonics

Synthesis of two-dimensional lead sheets by spark discharge in liquid nitrogen

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Particuology 2018年第5期16卷 152-159页

作者： Ahmad Hamdan Hiba Kabbara Cedric Noel Jaafar Ghanbaja Abdelkrim Redjaimia Thierry Belmonte Universite de Lorraine lnstitutJean tamourUMR CNRS 7198Nancy F-54042France CNRS lnstitutJean LamourUMR CNRS 7198Nancy F-54042France

A simple method to synthesise hexagonal lead sheets,which belong to the class of two-dimensional materials,is *** objects are collected on a substrate located under two lead electrodes, between which nanosecond-pulsed spark discharges are ignited in liquid *** hexagonal sheets are single crystals produced by gas phase *** nitrogen completely evaporates,the sheets change to PbO2by oxidation in *** oxidation process induces stress that pleats the uppermost sheets or open cracks at the *** thickness of the individual objects typically varies from 4to *** the number of discharges is more than about 2000,in addition to sheets,two types of PbO2 sticks start to form:bundles composed of nanosticks (length 5p.m and diameter 50nm)and isolated sticks (length 20μm and diameter 500nm).These new nanostructures mainly form because of the way the discharge erodes the lead ***,anisotropic erosion driven by the orientation of the crystallographic planes of the lead crystals produces octahedra and nanosticks,and the nanosticks grow on the electrode surfaces as discharge *** about 2000discharges,the nanosticks are sufficiently long that they can be easily broken,probably by mechanical stress,and they fall onto the underlying substrate.

关键词： Discharge in hquids Plasma-surface interaction Nanopamcles Liquid nitrogen Lead

Combining infrared and mode synthesizing atomic force microscopy： Application to the study of lipid vesicles inside Streptomyces bacteria

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Nano Research 2016年第6期9卷 1674-1681页

作者： Pauline Vitry Rolando Rebois Eric Bourillot Ariane Deniset-Besseau Marie-Joelle Virolle~ Eric Lesniewska Alexandre Dazzi ICB umr CNRS 6303 University ofBourgogne Franche Comte 21078 Dijon France LCP umr CNRS 8000 University Paris-Sud 91405 Orsay France 12BC umr CNRS 9198 University Paris-Sud 91190 Gif-Sur-Yvette France

We propose a new analytical approach combining vibrational spectroscopy and acoustic tomography for the detection and characterization of vesicles inside Streptomyces bacteria. Using atomic force microscopy and infrared spectroscopy （AFM-IR）, we detect the presence of triglyceride vesicles. Their sizes in depth are measured with high accuracy using mode synthesizing atomic force microscopy （MS-AFM）. We conducted a comparative study of AFM-IR and MS-AFM, and highlighted the advantages of the coupling of these techniques in having a full characterization （chemical, topographical, and volumetric） of a biological sample. With these complementary techniques, a complete access to the vesicle size distribution has been achieved with an accuracy of less than 50 nm. A 3D reconstruction of bacteria showing the in-depth distribution of vesicles is given to underline the great potential of the acoustic method.

关键词： nanoscale suDsurtace imaging atomic force microscop~ acoustic microscopy infrared microscopy biology

Addressing ore formation and exploration

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Geoscience Frontiers 2019年第4期10卷 1613-1622页

作者： Jean-Louis Vigneresse GéoRessources UMR 7339Université de Lorraine

Common base and noble metals represent an important economic factor in the actual industrial *** instance the world resources for copper are actually estimated for about the next 30 years *** situation requires rethinking the way major ore deposits form,leading to new guides for *** present paper briefly examines the processes leading to ore formation,in relation with granitic or granodioritic *** identifies the importance of metal enrichment during the magmatic *** the magma chamber that forms porphyry intrusions,metals may incorporate to first formed crystals,becoming inert;concentrate into the residual melt of a mush;or segregate by diffusion into the exsolved magmatic volatile phase(MVP)into which they are transported and precipitated.A competition results between elements partitioning and ***,a specific Peclet number for each metal(Cu,Au,Ag,Mo,W,Sn,and REE)controls the ratio between the diffusive and the advective *** diffusivity in the melt shows differential behavior relative to a threshold of about10 13 m2/*** with slower diffusivity values(***)will not ***,fast diffusive metals(Au,Ag,Cu)may rapidly incorporate the MVP,provided an adequate component(halogens or S)is attractive for *** chemistry of the MVP escaping the magma induces different alteration *** relative content in F,Cl or S,attested by the composition of biotites and apatites,links with the preferential content of metals in o re deposits,representing a valuable tool for *** the model is replaced in a set of coupled mechanical-chemical instabilities,within a three phase material.

关键词： Porphyry ore deposits Metals concentration processes Exploration Alteration pattern

On-surface synthesis of covalent coordination polymers on micrometer scale

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Nano Research 2017年第3期10卷 933-940页

作者： Mathieu Koudia Elena Nardi Olivier Siri Mathieu Abel Aix Marseille UniversitY CNRS IM2NP UMR 7334 13397 Marseille France Aix Marseille UniversitY CNRS CINaM UMR 7325 13288 Marseille France

On-surface synthesis under ultrahigh vacuum provides a promising strategy to control matter at the atomic level, with important implications for the design of new two-dimensional materials having remarkable electronic, magnetic, or catalytic properties. This strategy must address the problem of limited extension of the domains due to the irreversible nature of covalent bonds, which prevents the ripening of defects. We show here that extended materials can be produced by a controlled co-deposition process. In particular, co-deposition of quinoid zwitterion molecules with iron atoms on a Ag（111） surface held at 570 K allows the formation of micrometer-sized domains based on covalent coordination bonds. This work opens up the construction of micrometer-scale single-layer covalent coordination materials under vacuum conditions.

关键词： on-surface synthesis scanning tunnelingmicroscopy (STM) two-dimensional polymer covalent organic frameworks

Pivotal Role of PGE_2 and IL-10 in the Cross-Regulation of Dendritic Cell-Derived Inflammatory Mediators

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Cellular & Molecular Immunology 2006年第4期3卷 271-277页

作者： Hedi Harizi Norbert Gualde CNRS umr 5540 Bordeaux Université Bordeaux 2France

Exposure to pathogens induces antigen-presenting cells （APC） such as macrophages and dendritic cells （DC） to produce various endogenous mediators, including arachidonic acid （AA）-derived eicosanoids, cytokines, and nitric oxide （NO）. Many secreted products of activated APC can act by themselves in an autocrine manner and modulate their function. Moreover, the cross-interaction between endogenous bioactive molecules regulates the function of professional APC with important consequences for their ability to activate and sustain immune and inflammatory responses, and to regulate immune homeostasis. Although neglected for many years when compared to their role in cardiovascular homeostasis, cancer and inflammation, the importance of eicosanoids in immunology is becoming more defined. The role of prostaglandin （PG） E2 （PGE2）, one of the best known and most well studied eicosanoids, is of particular interest. It modulates the activities of professional DC by acting on their differentiation, maturation and their ability to secrete cytokines. Uniquely among haematopoietic cytokines, interleukin-10 （IL-10） is a pleiotropic molecule that displays both immunostimulatory and immunoregulatory activities. IL-10 has attached much attention because of its anti-inflammatory properties. It modulates expression of cytokines, soluble mediators and cell surface molecules by cells of myeloid origin, particularly macrophages and DC. We previously reported that PGE2 is a potent inducer of IL-10 in bone marrow-derived DC （BM-DC）, and PGE2-induced IL-10 is a key regulator of the BM-DC pro-inflammatory phenotype. BM-DC may be considered as an important model to study complex interactions between endogenous mediators, and autocrine IL-10 plays a pivotal role in the crossregulation of AA-derived lipid mediators, cytokines, and NO, with critical effects on immune and inflammatory responses.

关键词： BM-DC IL-10 PGE2 feed-back regulation cytokine inflammation

Alien calculus and non perturbative effectsin Quantum Field Theory

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Frontiers of physics 2016年第6期11卷 31-34页

作者： Marc P. Bellon Sorbonne Universites UPMC Univ Paris 06 UMR 7589 LPTHE 75005 Paris France CNRS UMR 7589 LPTHE 75005 Paris France

In many domains of physics, methods for dealing with non-perturbative aspects are required. Here, I want to argue that a good approach for this is to work on the Borel transforms of the quantities of interest, the singularities of which give non-perturbative contributions. These singularities in many cases can be largely determined by using the alien calculus developed by Jean Écalle. My main example will be the two point function of a massless theory given as a solution of a renormalization group equation.

关键词： Schwinger–Dyson equations series resommation alien calculus

Hepatitis C in Laos： A 7-Year Retrospective Study on 1765 Patients

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Virologica Sinica 2018年第4期33卷 295-303页

作者： Phimpha Paboriboune Thomas Vial Philavanh Sitbounlang Stephane Bertani Christian Trepo Paul Deny Francois-Xavier Babin Nicolas Steenkeste Pascal Pineau Eric Deharo Centre d'Infectiologie Lao-Christophe Merieux 3888 Vientiane Laos umr 152 pharmadev IRD Universite de ToulouseUPS 31062 Toulouse France INSERM U1052 CNRS UMR 5286 Cancer Research Centre of Lyon 69008 Lyon France Universite Paris 13 Sorbonne Paris Cite Hopitaux Universitaires Paris Seine Saint Denis 93000 Bobigny France Fondation Merieux 69002 Lyon France INSERM U993 Institut Pasteur Unite 'Organisation Nucleaire et Oncogenese' 75015 Paris France

Hepatitis C virus （HCV） is a global health concern, notably in Southeast Asia, and in Laos the presentation of the HCV- induced liver disease is poorly known. Our objective was thus to describe a comprehensive HCV infection pattern in order to guide national health policies. A study on a group of 1765 patients formerly diagnosed by rapid test in health centres was conducted at the Centre of Infectiology Lao Christophe Merieux in Vientiane. The demographic information of patients, their infection status （viral load： VL）, liver function （aminotransferases） and treatments were analysed. Results showed that gender distribution of infected people was balanced; with median ages of 53.8 for men and 51.6 years for women （13-86 years）. The majority of patients （72%） were confirmed positive （VL 〉 50 IU/mL） and 28% of them had high VL （〉 61oglo）. About 23% of patients had level of aminotransferases indicative of liver damage （〉 40 IU/mL）; but less than 20% of patients received treatment. Patients rarely received a second sampling or medical imaging. The survey also showed that cycloferon, pegylated interferon and ribavirin were the drugs prescribed preferentially by the medical staff, without following any international recommendations schemes. In conclusion, we recommend that a population screening policy and better management of patients should be urgently implemented in the country, respecting official guidelines. However, the cost of biological analysis and treatment are significant barriers that must be removed. Public health resolutions should be immediately enforced in the perspective of meeting the WHO HCV elimination deadline by 2030.

关键词： Hepatitis C virus (HCV) HCV incidence Antiviral agents Laos