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The response of a position-sensitive Li-glass scintillator detector to alpha-particles from a collimated 241Am source scanned across the face of the detector has been measured. Scintillation light was read out by an 8x8 pixel multi-anode photomultiplier and the signal amplitude for each pixel has been recorded for every position on a scan. The pixel signal is strongly dependent on position and in general several pixels will register a signal (a hit) above a given threshold.
La métrologie (spectroscopie, mesures de temps ou de distances) ou encore la réalisation de réseaux optiques quantiques nécessitent des sources de photons uniques efficaces.
A. Theodoratou, L.-T. Lee, J. Oberdisse and A. Aubert-Pouëssel, Langmuir 35(20) (2019) 6620. Abstract : Nanofilms of about 2 nm thickness have been formed at the air–water interface using functionalized castor oil (ICO) with cross-linkable silylated groups.
"Dynamics properties of photosynthetic microorganisms probed by incoherent neutron scattering" Daniela Russo, Maya Dimova Lambreva, Christiane Alba Simionesco, Pierre Sebban, and Giuseppina Rea Biophysical Journal, 116 (9) (2019) 1759-1768 Studies on the dynamical properties of photosynthetic membranes of land plants and purple bacteria have been previously performed by neutron spectroscopy, revealing a tight coupling between specific photochemical reactions and macromolecular dynamics.
B. Annighöfer , A. Hélary, A. Brulet, A. Colas de la Noue, C. Loupiac and S. Combet Review of Scientific Instruments 90 (2019) 025106 Abstract : We report on a high pressure (HP) cell designed for the determination of the structure of molecular solutions by small-angle neutron scattering (SANS). The HP cell is fitted up with two thick metallic windows that make the device very resistant under hydrostatic pressures up to 600 MPa (or 6 kbar).
Andrés Marcoleta, Frank Wien, Véronique Arluison, Rosalba Lagos, Rafael Giraldo Bacterial Amyloids (2019) Amyloids are supramolecular protein assemblies based on fibrillar arrangements of β‐sheets that were first found as linked to neurodegenerative and systemic human diseases. However, there is now overwhelming evidence on alternative roles of amyloids as functional assemblies and as epigenetic determinants of beneficial traits, both in Fungi and Metazoa.
Des chercheurs du SPEC, en collaboration avec le Laboratoire de Physique des Solides d’Orsay, le Laboratoire National des Champs Magnétiques Intenses de Toulouse et le Département de Physique de l’Université de Sherbrooke au Canada, ont récemment mis en évidence que les supraconducteurs à haute température critique, fortement dopés, présentent, dans leur état normal métallique, un comportement résistif universel, impliquant une limite quantique de dissipation de l’énergie, en lien avec le principe d'incertitude d'Heisenberg entre temps et énergie.
Annelies Sels, Giovanni Salassa, Fabrice Cousin, Lay-Theng Lee, Thomas Bürgi, Nanoscale 26 (2018) 12754. Aromatic dithiol linkers were used to prepare aggregates of Au25(SR)18 clusters (SR: thiolate) via ligand exchange reactions. Fractions of different aggregate sizes were separated by size exclusion chromatography (SEC).
Marguerite Léang, Didier Lairez, Fabrice Cousin, Frédérique Giorgiutti-Dauphiné, Ludovic Pauchard, Lay-Theng Lee During evaporative drying of a colloidal dispersion, the structural behavior at the air-dispersion interface is of particular relevance to the understanding of the consolidation mechanism and the final structural and mechanical properties of the porous media.
Burkhard Annighöfer, Arnaud Hélary, Annie Brûlet, Alexandre Colas de la Noue, Camille Loupiac, and Sophie Combet We report on a high pressure (HP) cell designed for the determination of the structure of molecular solutions by small-angle neutron scattering (SANS). The HP cell is fitted up with two thick metallic windows that make the device very resistant under hydrostatic pressures up to 600 MPa (or 6 kbar).
M. Deutsch, W. Peng, P. Foury-Leylekian, V. Balédent, S. Chattopadhyay, M. T. Fernandez-Diaz, T. C. Hansen, A. Forget, D. Colson, M. Greenblatt, M.-B. Lepetit, S. Petit, and I. Mirebeau The magnetic structure of TbMn2O5 and DyMn2O5 multiferroics has been studied by high-pressure neutron diffraction in a large pressure range up to 6.6 GPa.
The electron is an elementary particle carrying the elementary charge "e" that is a fundamental constant of physics. However, in a 2-dimensional confined conductor within an intense magnetic field (~ 10 T), the electrons can be organized into a new topologically correlated quantum state so that the electric current can be transported by fractional charges: e / 3, e / 4, e / 5 ....
L’avènement des lasers femtosecondes (1fs = 10-18s) de puissance avec la technique "Chirped Pulse Amplification" (CPA) [1] permet aujourd’hui de délivrer des intensités lumineuses gigantesques (> 1021 W.cm-2) associées à des champs électriques ultra-intenses de l’ordre de 1013 V.m-1.
Sophie Combet, Fabrice Cousin, Human Rezaei, Sylvie Noinville Soluble oligomers of prion proteins (PrP), produced during amyloid aggregation, have emerged as the primary neurotoxic species, instead of the fibrillar end-products, in transmissible spongiform encephalopathies. However, whether the membrane is among their direct targets, that mediate the downstream adverse effects, remains a question of debate.
Souha Ben Mahmoud, Wafa Essafi, Annie Brûlet and François Boué The chain conformation in sulfonated polystyrene PSSNa of a degree of sulfonation 0.34 ≤ f ≤ 1, i.e., of various hydrophobicity, is followed in mixtures of water and increasing content of tetrahydrofuran (THF), a good solvent of the hydrophobic polystyrene moieties (which improves the solvent quality of the mixture).
Jyotsana Lal This article is dedicated to the memory of Loic Auvray The results on Winsor phases, droplet and bicontinous microemulsions phases with polymer-grafted lipids studied by Small Angle Neutron Scattering (SANS) are reported below, together with the contrast variation techniques used to characterize the average curvature in the system.
Raphael Dos Santos Morais, Olivier Delalande, Javier Perez, Dominique Mias-Lucquin, Melanie Lagarrigue, Anne Martel, Anne-Elisabeth Molza, Angelique Cheron, Celine Raguenes-Nicol, Thomas Chenuel, Arnaud Bondon, Marie-Sousai Appavou, Elisabeth Le Rumeur, Sophie Combet, and Jean-Francois Hubert Scaffolding proteins play important roles in supporting the plasma membrane (sarcolemma) of muscle cells.
Fengjiao Qian, Lars J. Bannenberg, Heribert Wilhelm, Grégory Chaboussant, Lisa M. Debeer-Schmitt, Marcus P. Schmidt, Aisha Aqeel, Thomas T. M. Palstra, Ekkes Brück, Anton J. E. Lefering, Catherine Pappas, Maxim Mostovoy, Andrey O.
I. Mirebeau, N. Martin, M. Deutsch, L. J. Bannenberg, C. Pappas, G. Chaboussant, R. Cubitt, C. Decorse, and A. O. Leonov Reentrant spin glasses are frustrated disordered ferromagnets developing vortexlike textures under an applied magnetic field. Our study of a Ni0.81Mn0.19Ni0.81Mn0.19 single crystal by small angle neutron scattering clarifies their internal structure and shows that these textures are randomly distributed.
Maelenn Chevreuil, Didier Law-Hine, Jingzhi Chen, Stéphane Bressanelli, Sophie Combet, Doru Constantin, Jéril Degrouard, Johannes Möller, Mehdi Zeghal and Guillaume Tresset The survival of viruses partly relies on their ability to self-assemble inside host cells. Although coarse-grained simulations have identified different pathways leading to assembled virions from their components, experimental evidence is severely lacking.
Pure spin conductors could behave as nonlinear component in the high power regime, hereby opening up considerably the realm of functions realizable with magnetic materials. An additional feature is that these are continuously tunable by an external magnetic field.  
Unravelling a mechanism of action for a cecropin a‑melittin hybrid antimicrobial peptide: the induced formation of multilamellar lipid stacks T. Silva, B. Claro, B. F. B. Silva, N. Vale, P. Gomes, M.-S. Gomes, S. S. Funari, J. Teixeira, D. Uhríková, and M. Bastos, Langmuir, 2018, 34 (5), pp 2158–2170. An understanding of the mechanism of action of antimicrobial peptides is fundamental to the development of new and more active antibiotics.
Béatrice Gillon, Albert Hammerschmied, Arsen Gukasov, Alain Cousson, Thomas Cauchy, Eliseo Ruiz, John A. Schlueter, Jamie L. Manson We report neutron‐diffraction investigations of the quasi‐2D MnII(dca)2(pym)(H2O) (pym = N2C4H4) compound, where high‐spin MnII ions are bridged by dicyanamide anions, [N(CN)2]– (herein abbreviated dca). Inside the layers, Mn2+ ions are connected by single or double dca bridges.
Anne-Sophie Robbes, Fabrice Cousin , Florian Meneau, and Jacques Jestin We probe by SANS the conformation of polymer chains of the matrix in various nanocomposites based on the same building blocks, namely spherical magnetic nanoparticles of maghemite (γ-Fe2O3) as fillers and polystyrene (PS) for the matrix.
We report on the self-assembly behavior of poly(2-methyl-2-oxazoline)–block–poly(2-octyl-2-oxazoline) comprising different terminal perfluoroalkyl fragments in aqueous solutions. As reported previously [Kaberov et al. (2017)] such polyphiles can form a plethora of nanostructures depending of the composition and on the way of preparation.
Cationic thermoresponsive poly(n-vinylcaprolactam) microgels synthesized by emulsion polymerization using a reactive cationic macro-raft agent L. Etchenausia, E. Deniau, A. Brûlet, J. Forcada and M. Save,  Macromolecules  (2018) sous presse.
Magnetic skyrmions are topologically stable, vortex-like objects surrounded by chiral boundaries that separate a region of reversed magnetization from the surrounding magnetized material. They are closely related to nanoscopic chiral magnetic domain walls, which could be used as memory and logic elements for conventional and neuromorphic computing applications that go beyond Moore’s law.
Publication by Springer Eds of the book ( ISBN 978-1-4939-7634-8): "Bacterial regulatory RNA" Methods and Protocols     © 2018 Editors: Veronique Arluison, , Claudio Valverde Collection : Methods in Molecular Biology Including the contribution: "Techniques to analyse sRNA protein cofactor self-assembly in vitro" D. Partouche, A. Malabirade, T. Bizien, M. Velez, S. Trepout, S. Marco, V. Militello, C. Sandt, F. Wien and V.
La résonance magnétique a un impact important dans nos vies de tous les jours, de l’imagerie médicale au contrôle qualité dans la production de bière. Cette technique utilise de puissants aimants et des impulsions radio-fréquence ou micro-ondes pour révéler de faibles concentrations de molécules dans une substance.
D. Bounoua, R. Saint-Martin, S. Petit, P. Berthet, F. Damay, Y. Sidis, F. Bourdarot, and L. Pinsard-Gaudart, Phys. Rev. B 95, 224429 The low energy magnetic excitations spectra of the pristine and doped quasi-one-dimensional spin chains cuprates SrCuO2 have been investigated by inelastic neutron scattering.


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