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1. Laser shock experiments to investigate and to model various aspects of the response of metals to shock loading

Author

Berthe L., Cuq-Lelandais J.P., Boustie M., Dragon A., Loison D., Signor L., Lescoute E., and de Rességuier T.

Subjects
Physics, QC1-999
Abstract

Laser driven shocks allow studying the dynamic behaviour of condensed matter over small spatial (∼μm to mm-order) and temporal (∼ps to ns-order) scales, at extremely high strain rates (∼107 s−1). They can be used to test the predictive capability of constitutive models over wide ranges of loading pressures and pulse durations. We present experimental results in laser shock-loaded metals (iron, gold, tin), based on various, complementary techniques including time-resolved velocity measurements, transverse shadowgraphy and post-shock analyses of recovered samples. The data are used to investigate several shock wave processes such as yielding and polymorphic transformations, melting, spall fracture and dynamic fragmentation in both solid and melted states. On the basis of comparisons with numerical simulations, the abilities and limitations of several models are briefly discussed.

Published
2011
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2. Experimental study of dynamic fragmentation of shockloaded metals below and above melting

Author

De Rességuier T., Dragon A., Loison D., Lescoute E., Signor L., and Roy G.

Subjects
Physics, QC1-999
Abstract

The breakout and reflection of a strong shock-wave upon the free surface of a metallic sample may lead to ejecta production of many types. Spall fracture is due to tensile stresses which result from the interaction of the incident and the reflected release waves. When the sample remains in solid state, one or several layers of finite thickness, called spalls, can be created and ejected. When melting is initiated during shock-wave propagation, tensile stresses are generated in a liquid medium and lead to the creation of an expanding cloud of liquid debris. This phenomenon, sometimes referred to as microspalling, consists in a dynamic fragmentation process in the melted material. The present paper is devoted to the experimental investigation of the transition from spall fracture in solid state to the micro-spalling process in molten metals. This study, realized on tin and on iron, involves different shock generators (gas gun, pulsed laser…) and diagnostics (velocimetry, high-speed optical shadowgraphy, fragments recovery).

Published
2010
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8. Assembly of the mitochondrial complex I assembly complex suggests a regulatory role for deflavination

Author

Giachin, G., Jessop, M., Bouverot, R., Acajjaoui, S., Saïdi Me., Chretien, A., Bacia-Verloop, M., Signor, L., Mas, P.J., Favier, A., Borel Meneroud, E., Hons, M., Hart, D.J., Kandiah, E., Boeri Erba, E., Buisson, A., Leonard, G., Gutsche, I., and Soler-López, M.

Abstract

Fatty acid β‐oxidation (FAO) and oxidative phosphorylation (OXPHOS) are mitochondrial redox processes that generate ATP. The biogenesis of the respiratory Complex I, a 1 MDa multiprotein complex that is responsible for initiating OXPHOS, is mediated by assembly factors including the mitochondrial complex I assembly (MCIA) complex. However, the organisation and the role of the MCIA complex are still unclear. Here we show that ECSIT functions as the bridging node of the MCIA core complex. Furthermore, cryo‐electron microscopy together with biochemical and biophysical experiments reveal that the C‐terminal domain of ECSIT directly binds to the vestigial dehydrogenase domain of the FAO enzyme ACAD9 and induces its deflavination, switching ACAD9 from its role in FAO to an MCIA factor. These findings provide the structural basis for the MCIA complex architecture and suggest a unique molecular mechanism for coordinating the regulation of the FAO and OXPHOS pathways to ensure an efficient energy production.

Published
2021

11. Laser-driven shocks to explore the effects of aging on the adhesion of silver sintered on copper substrate.

Author

de Rességuier, T., Milhet, X., Labussière, V., Barraud, E., Signor, L., and Baillargeat, J.

Subjects
SILVER, POWER electronics, COPPER, INTERFACE dynamics, METALLIC films
Abstract

The adhesion of thin silver joints sintered on metallic substrates is a major issue for their potential use in power electronics modules. Here, we explore how laser shock-induced spallation can provide a way to study this adhesion. Due to wave interactions inside the shock-loaded assembly, dynamic tensile stresses are induced near the copper-silver interface, resulting in partial or full removal of the silver layer. In order to investigate the effects of aging on the interface strength, experiments are performed on both as-sintered and aged samples. Time-resolved measurements of the free surface velocity provide information on wave dynamics and interface failure, but finite-element simulations show that inferring a quantitative value of the bonding strength from these data is still challenging. Nevertheless, post-recovery observations provide original insight into the debonding process, including some complex effects of aging, consistent with trends reported in the literature. [ABSTRACT FROM AUTHOR]

Published
2022
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13. Tailing miniSOG: structural bases of the complex photophysics of a flavin-binding singlet oxygen photosensitizing protein

Author

Torra J., Lafaye C., Signor L., Aumonier S., Flors C., Shu X., Nonell S., Gotthard G., Royant A. and We thank Rubén Ruiz-González, Marjolaine Noirclerc-Savoye and David von Stetten for their contribution at an early stage of the project. The ESRF is acknowledged for access to beamlines and facilities for molecular biology via its in-house research program. AR acknowledges funding from the French Agence Nationale de la Recherche (project SOxygen, ANR-11-JSV5-0009 and project CrystalBall, ANR-14-CE06-0005-02), from the Spanish Ministerio de Economía y Competitividad (CTQ2016-78454-C2-1-R, MAT2015-66605-P and SEV-2016-0686) and the Fundació la Marató de TV3 (grant No. 20133133). This work used the platforms of the Grenoble Instruct-ERIC Center (ISBG: UMS 3518 CNRS-CEA-UGA-EMBL) with support from FRISBI (ANR-10-INBS-05-02) and GRAL (ANR-10-LABX-49-01) within the Grenoble Partnership for Structural Biology (PSB).

Published
2019

18. Alcohol User Profile after a Brief Motivational Intervention in Telephone Follow-up: Evidence Based on Coping Strategies

Author

Signor L, es S, Tatay Cm, Fern, Figueiró Lr, and Constant Hmrm

Subjects
Coping (psychology), Evidence-based practice, User profile, Addiction, media_common.quotation_subject, Motivational interviewing, Alcohol abuse, Alcohol, medicine.disease, 030227 psychiatry, 03 medical and health sciences, chemistry.chemical_compound, Alcohol abusers, 0302 clinical medicine, chemistry, medicine, Psychology, 030217 neurology & neurosurgery, media_common, Clinical psychology
Abstract

Despite the promising results which were achieved under different intervention programs in alcohol abuse, its beneficial effects seem to vary among patients. In this way, a variable of interest might be the way to deal with a specific situation. Not surprisingly, escaping addiction has also been studied as an underlying ineffective strategy. Thus, to assess the effect of brief motivational intervention on coping strategies, a 6 months treatment was carried out in alcohol abusers. Moreover, differences among these patients’ profiles were examined according to their coping outcomes. The survey was conducted by telephone, employing the Coping Behaviours Inventory (CBI) as a dependent measure. A sample of 120 participants took part in the study. Participants were randomly assigned to 2 groups: Intervention (IBM) or control (without intervention). The analysis of the participants’ profiles resulted in 3 different groups: i) Most of the participants were in the control group and did not stop drinking, ii) All participants were in the control group and stopped drinking, and iii) All the participants were in the experimental group and almost all of them stopped drinking. With regards to coping strategies, participants in the last group showed better CBI scores. The results help to better understand the profile of users of alcohol following treatment, as well as the kind of strategies that they might use to stop substance use. They also depicted a more homogeneous coping pattern for those participants after intervention and some unusual profile features among the control group.

Published
2017

19. Spallation in laser shock-loaded tin below and just above melting on release.

Author

de Rességuier, T., Signor, L., Dragon, A., Severin, P., and Boustie, M.

Subjects
*TIN, *LIQUID metals, *FREE surfaces (Crystallography), *SPALLATION (Nuclear physics), *STRAINS & stresses (Mechanics)
Abstract

Spall damage in solid materials has been one of the most widely studied shock-induced phenomena for several decades, for both applied and basic scientific motivations. Comparatively, very little data can be found yet about spallation in liquid metals. In a recent paper, we have reported an exploratory investigation of liquid spall in tin samples melted upon laser shocks of very high intensities. Here, we present further experimental results obtained over a lower pressure range, where we focus on the transition from the ductile fracture behavior of solid tin to the cavitating spall expected above melting. This transition is clearly evidenced from both time-resolved free surface velocity measurements and post-test examination of the recovered targets. The drop in tensile strength associated with melting is evaluated from the velocity profiles. Detailed views of the fracture surfaces in the spall craters provide an insight into the cavitation process. Experimental data are compared to preliminary computations to determine the loading pressures and to assess the overall consistency of our interpretation of the results. [ABSTRACT FROM AUTHOR]

Published
2007
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20. Experimental investigation of liquid spall in laser shock-loaded tin.

Author

de Rességuier, T., Signor, L., Dragon, A., Boustie, M., Roy, G., and Llorca, F.

Subjects
*METALS, *MELTING points, *LIQUIDS, *SPALLATION (Nuclear physics), *CAVITATION, *LASERS, *POLYCARBONATES, *PHENOMENOLOGY, *PRESSURE
Abstract

When a metal is shocked above its melting pressure or melted on release, the tensile stresses generated upon reflection of the compressive pulse from a free surface are induced into a liquid state. Instead of the well-known spallation process observed in solid targets, cavitation is expected in the melted material, and liquid fragments are ejected from the free surface. Their size, velocity, and temperature distributions are issues of increasing interest, as well as their impact on other nearby materials, but data are limited on the subject. Here, we present an experimental study performed on tin samples subjected to high pressure laser shocks (ranging from about 50 to 200 GPa) of short duration (∼5 ns). The results include post-test observations of the ejecta recovered after impact on a polycarbonate shield and time-resolved measurements of the free surface velocity through the shield. For shock pressures below some 80 GPa, the velocity profiles are compared to the predictions of one-dimensional simulations involving a multiphase equation of state. For higher loading pressures, the emergence of the shock at the free surface produces a rapid loss of reflectivity so the particle velocity cannot be determined. In all cases, solidified fragments of tin are recovered on the shield. Their sizes, their shapes, and the induced damage depend significantly on shock pressure, and are indicative of a very wide range of ejection velocities. The data provide a basis for a phenomenological description of the process. [ABSTRACT FROM AUTHOR]

Published
2007
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21. Which aggregate complexity is required for an accurate computation off stress and plastic strain fields?

Author

Sauzay, M., Liu, J., Rachdi, F., Signor, L., Ghidossi, T., Villechaise, P., CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Université Pierre et Marie Curie - Paris 6 (UPMC), Institut Pprime (PPRIME), Université de Poitiers-ENSMA-Centre National de la Recherche Scientifique (CNRS), and amplexor, amplexor

Subjects
[PHYS.NUCL] Physics [physics]/Nuclear Theory [nucl-th], FE method, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], Crystal Plasticity, mean-field homogeneisation, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Multiscale Modeling
Abstract

International audience; The increasing efficiency of computations allows the numerical evaluation of stress and plastic strain fields in aggregates which description is finer and finer. Either the FE metof or the FFT method may be used. During the two last decades, such numerical computations lead to many new results, for instance allowing the validation of mean field homogeneisation schemes.

Published
2015

22. In vitro reconstitution of peptidoglycan assembly from the Gram-positive pathogen Streptococcus pneumoniae

Author

Zapun, A., Philippe, J., Abrahams, K.A., Signor, L., Roper, D.I., Breukink, E.J., Vernet, T., Membrane Biochemistry and Biophysics, Sub Membrane Biochemistry & Biophysics, Institut de biologie structurale (IBS - UMR 5075 ), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Thomas, Frank, and Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG)

Subjects
MESH: Peptidyl Transferases, Glutamine, medicine.disease_cause, Biochemistry, Bacterial cell structure, law.invention, chemistry.chemical_compound, law, Cell Wall, Homologous Recombination, Pathogen, 0303 health sciences, MESH: Penicillin-Binding Proteins, biology, Lipid II, [SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Structural Biology [q-bio.BM], MESH: Peptidoglycan, General Medicine, MESH: Glutamic Acid, Uridine Diphosphate N-Acetylmuramic Acid, Anti-Bacterial Agents, Streptococcus pneumoniae, Recombinant DNA, MESH: Uridine Diphosphate N-Acetylmuramic Acid, Molecular Medicine, MESH: Genetic Engineering, MESH: Peptidoglycan Glycosyltransferase, Genetic Engineering, MESH: Streptococcus pneumoniae, Glycan, [SDV.BBM.BS] Life Sciences [q-bio]/Biochemistry, Molecular Biology/Structural Biology [q-bio.BM], Glutamic Acid, Peptidoglycan, beta-Lactams, beta-Lactam Resistance, Microbiology, MESH: Homologous Recombination, 03 medical and health sciences, MESH: Cell Wall, MESH: beta-Lactams, MESH: Anti-Bacterial Agents, Glycosyltransferase, medicine, Penicillin-Binding Proteins, 030304 developmental biology, MESH: Glutamine, 030306 microbiology, MESH: beta-Lactam Resistance, chemistry, Peptidyl Transferases, biology.protein, Peptidoglycan Glycosyltransferase
Abstract

International audience; Understanding the molecular basis of bacterial cell wall assembly is of paramount importance in addressing the threat of increasing antibiotic resistance worldwide. Streptococcus pneumoniae presents a particularly acute problem in this respect, as it is capable of rapid evolution by homologous recombination with related species. Resistant strains selected by treatment with β-lactams express variants of the target enzymes that do not recognize the drugs but retain their activity in cell wall building, despite the antibiotics being mimics of the natural substrate. Until now, the crucial transpeptidase activity that is inhibited by β-lactams was not amenable to in vitro investigation with enzymes from Gram-positive organisms, including streptococci, staphylococci, or enterococci pathogens. We report here for the first time the in vitro assembly of peptidoglycan using recombinant penicillin-binding proteins from pneumococcus and the precursor lipid II. The two required enzymatic activities, glycosyl transferase for elongating glycan chains and transpeptidase for cross-linking stem-peptides, were observed. Most importantly, the transpeptidase activity was dependent on the chemical nature of the stem-peptide. Amidation of the second residue glutamate into iso-glutamine by the recently discovered amido-transferase MurT/GatD is required for efficient cross-linking of the peptidoglycan.

Published
2013

25. Dynamic fragmentation of melted metals upon intense shock wave loading. Some modelling issues applied to a tin target, Archives of Mechanics

Author

Signor, L., Dragon, A., Roy, G., Rességuier, T., Llorca, F., Laboratoire de combustion et de détonique (LCD), and Université de Poitiers-ENSMA-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2008

26. Fragmentation dynamique de l'étain : de l'écaillage au micro-écaillage

Author

Rességuier, T., Signor, L., Dragon, A., Boustie, M., Berthe, L., Laboratoire de combustion et de détonique (LCD), Université de Poitiers-ENSMA-Centre National de la Recherche Scientifique (CNRS), Laboratoire pour l'application des lasers de puissance (LALP), Centre National de la Recherche Scientifique (CNRS), Science et Ingénierie des Matériaux et Procédés (SIMaP), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Published
2007

33. DEBRIS CLOUD EJECTION FROM SHOCK-LOADED TIN MELTED ON RELEASE OR ON COMPRESSION

Author

Signor, L., primary, Roy, G., additional, Chanal, P.-Y., additional, Héreil, P.-L., additional, Buy, F., additional, Voltz, C., additional, Llorca, F., additional, De Rességuier, T., additional, Dragon, A., additional, Elert, Mark, additional, Furnish, Michael D., additional, Anderson, William W., additional, Proud, William G., additional, and Butler, William T., additional

Published
2009
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37. DEBRIS CLOUD EJECTION FROM SHOCK-LOADED TIN MELTED ON RELEASE OR ON COMPRESSION.

Author

Signor, L., Roy, G., Chanal, P.-Y., Héreil, P.-L., Buy, F., Voltz, C., Llorca, F., De Rességuier, T., and Dragon, A.

Subjects
*SHOCK waves, *COMPRESSION fractures, *MECHANICAL shock, *FRAGMENTATION reactions, *CHEMICAL reactions
Abstract

A triangular shock-wave of sufficient intensity propagating in a metal sample may induce melting. When it reaches the free surface, tensile stresses are generated in the liquid state and lead to the creation of an expanding cloud of liquid debris. This phenomenon called micro-spalling consists in a dynamic fragmentation process in the melted material. Plate impact experiments, associated to the so-called Asay window technique, have been performed on tin to investigate this phenomenon. [ABSTRACT FROM AUTHOR]

Published
2009
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38. TRANSITION FROM SOLID TO LIQUID SPALL IN TIN UNDER LASER SHOCKS OF INCREASING INTENSITY.

Author

de Rességuier, T., Signor, L., Dragon, A., Severin, P., and Boustie, M.

Subjects
*STRAINS & stresses (Mechanics), *FREE surfaces (Crystallography), *CAVITATION, *LASERS, *HYDRODYNAMICS, *PARTICLES (Nuclear physics)
Abstract

When a shock-loaded target is melted on compression or on release, the tensile stresses generated upon reflection of the pressure pulse from a free surface are induced in a liquid state. Instead of the well-known spallation process occurring in solid targets, cavitation takes place in the melted material and liquid fragments are ejected from the free surface. Although increasing interest is manifested on the subject, related data are still scarce. In a recent paper, we have reported an exploratory investigation of liquid spall in tin targets submitted to intense laser shocks. Here, we present new results obtained over a lower pressure range, where we focus on the progressive transition from the ductile fracture behaviour of solid tin to the cavitation expected above melting. Both time-resolved free surface velocity measurements and post-test examination of the recovered samples clearly indicate this transition. Incipient melting produces a decrease in tensile strength that can be evaluated from the velocity profiles. Scanning electron micrographs of the fracture surfaces confirm such melting and provide an insight into the cavitation process. [ABSTRACT FROM AUTHOR]

Published
2007
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39. FRAGMENT-SIZE PREDICTION DURING DYNAMIC FRAGMENTATION OF SHOCK-MELTED TIN: RECOVERY EXPERIMENTS AND MODELING ISSUES.

Author

Signor, L., de Rességuier, T., Roy, G., Dragon, A., and Llorca, F.

Subjects
*SHOCK waves, *DETONATION waves, *LIQUID metals, *TIN, *CONDENSED matter, *MECHANICAL shock
Abstract

We are interested in dynamic fragmentation of shock-melted metals. The present work is devoted to laser-shock experiments in tin samples including fragments recovery and post-test evaluation of the fragment-size distribution. These results are compared with theoretical predictions from hydrocode simulations coupled with a modified formulation of a fragmentation model from the literature. [ABSTRACT FROM AUTHOR]

Published
2007
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40. Liquid spall in laser shock-loaded Tin melted on compression or on release

Author

de Rességuier, T., Signor, L., Dragon, A., Boustie, M., Roy, G., Llorca, F., de Rességuier, T., Signor, L., Dragon, A., Boustie, M., Roy, G., and Llorca, F.

Abstract

In a metal shocked above its melting pressure or melted on release, the tensile stresses generated when the compressive pulse reflects from a free surface are induced in a liquid state. Instead of the well-known spallation process observed in solid targets, one may expect the ejection of liquid fragments from the free surface. Their formation, evolution and impact on a remote obstacle are issues of increasing interest, but very scarce data have been published on the subject yet. In this paper, we present experimental results on tin samples submitted to high pressure laser shocks, including post-test observations of the ejecta recovered after impact on a polycarbonate shield, coupled with time-resolved VISAR measurements of the free surface velocity through this shield. For shock pressures below some 80 GPa, the records can be compared to simulations involving a multi-phase equation of state. For higher loading pressures, the arrival of the shock at the free surface produces a rapid loss of reflected signal, so the particle velocity cannot be determined. In all cases, solidified fragments of tin are recovered on the shields. Their aspect indicates a very wide range of ejection velocities, and their size distribution depends significantly on shock pressure.

Published
2006
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42. Dynamic fragmentation of laser shock-melted tin: experiment and modelling.

Author

Rességuier, T., Signor, L., Dragon, A., and Roy, G.

Subjects
*FRAGMENTATION reactions, *METALS, *TIN, *LASERS, *CAVITATION
Abstract

Dynamic fragmentation of shock-loaded metals is an issue of considerable importance for both basic science and a variety of technological applications, such as pyrotechnics or inertial confinement fusion, the latter involving high energy laser irradiation of thin metallic shells. Whereas spall fracture in solid materials has been extensively studied for many years, little data can be found yet about the evolution of this phenomenon after partial or full melting on compression or on release. Here, we present an investigation of dynamic fragmentation in laser shock-melted tin, from the “micro-spall” process (ejection of a cloud of fine droplets) occurring upon reflection of the compressive pulse from the target free surface, to the late rupture observed in the unspalled melted layer (leading to the formation of larger spherical fragments). Experimental results consist of time-resolved velocity measurements and post-shock observations of recovered targets and fragments. They provide original information regarding the loss of tensile strength associated with melting, the cavitation mechanism likely to occur in the melted metal, the sizes of the subsequent fragments and their ejection velocities. A theoretical description based on an energetic approach adapted to the case of a liquid metal is implemented as a failure criterion in a one-dimensional hydrocode including a multi-phase equation of state for tin. The resulting predictions of the micro-spall process are compared with experimental data. In particular, the use of a new experimental technique to quantify the fragment size distributions leads to a much better agreement with theory than previously reported. Finally, a complementary approach focused on cavitation is proposed to evaluate the role of this phenomenon in the fragmentation of the melted metal. [ABSTRACT FROM AUTHOR]

Published
2010
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43. Dynamic fragmentation of melted metals upon intense shock wave loading. Some modelling issues applied to a tin target.

Author

SIGNOR, L., DRAGON, A., ROY, G., DE RESSEGUIER, T., and LLORCA, F.

Subjects
*METALS, *SHOCK waves, *PHYSICS, *CAVITATION, *NUCLEATION, *TIN
Abstract

WE ARE INTERESTED in the dynamic fragmentation event produced in shock-melted metals called micro-spalling. Global energetic approach is briefly reviewed. It provides a general modelling framework that leads to realisticfragment-size predictions. But the actual physical mechanisms involved remain poorly understood. We attempt to explore the conditions under which cavitation, i.e. nucleation and growth of microvoids, may be responsible for fragmentation. This cavitation process is described by means of a hollow sphere model whose matrix is made of liquid tin. [ABSTRACT FROM AUTHOR]

Published
2008

47. Debris cloud ejection from shock-loaded tin melted on release or on compression

Author

Signor, L., Roy, G., Chanal, P.y, Héreil, P.-L., Buy, F., Voltz, C., de Resseguier, T., Dragon, A., Laboratoire de combustion et de détonique (LCD), Université de Poitiers-ENSMA-Centre National de la Recherche Scientifique (CNRS), VALDUC (DAM/VALDUC), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire de Mécanique et Technologie (LMT), École normale supérieure - Cachan (ENS Cachan)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Mécanique et Physique des Matériaux (LMPM), and Centre National de la Recherche Scientifique (CNRS)-ENSMA-Université de Poitiers

Subjects
[SPI]Engineering Sciences [physics], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

48. Dynamic fragmentation of laser shock-loaded materials, Shrapnel and debris meeting

Author

De Resseguier, T., Signor, L., Torrent, C., Boustie, M., Berthe, L., Laboratoire de combustion et de détonique (LCD), Université de Poitiers-ENSMA-Centre National de la Recherche Scientifique (CNRS), Laboratoire pour l'application des lasers de puissance (LALP), Centre National de la Recherche Scientifique (CNRS), Science et Ingénierie des Matériaux et Procédés (SIMaP), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

49. A solvent-exposed cysteine forms a peculiar Ni(II)-binding site in the metallochaperone CooT from Rhodospirillum rubrum

Author

Christine Cavazza, Francesco Musiani, Mauro Rovezzi, Luca Signor, Marila Alfano, Giulia Veronesi, Barbara Zambelli, Stefano Ciurli, Olivier Proux, Biocatalyse (BIOCAT), Laboratoire de Chimie et Biologie des Métaux (LCBM - UMR 5249), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Groupe modélisation et chimie théorique (MCT), Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology, Groupe Infection virale et cancer (IBS-VIC), Institut de biologie structurale (IBS - UMR 5075), Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Biocatalyse (BIOCAT ), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), University of Bologna, Institut de biologie structurale (IBS - UMR 5075 ), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), ITERLIS PhD program, CEA Life sciences Labex ARCANE CBH-EUR-GS ANR-17-EURE-0003European Cooperation in Science and Technology (COST)CA15133FRISBI within the Grenoble Partnership for Structural Biology (PSB) ANR-10-INBS-05-02ISBG: UMS3518CNRS-CEA-UGA-EMBLGRAL within the Grenoble Partnership for Structural Biology (PSB) ISBG: UMS3518CNRS-CEA-UGA-EMBLANR-10-LABX-49-01Department of Pharmacy and Biotechnology of the University of Bologna 'FUNBIOCO' project (IDEX-UGA, Initiatives de Recherche stratgiques) 'COSYNBIO' project (Projets exploratoires, Cellule energie-CNRS), ANR-17-EURE-0003,CBH-EUR-GS,CBH-EUR-GS(2017), ANR-10-INBS-0005,FRISBI,Infrastructure Française pour la Biologie Structurale Intégrée(2010), ANR-10-LABX-0049,GRAL,Grenoble Alliance for Integrated Structural Cell Biology(2010), Alfano M., Veronesi G., Musiani F., Zambelli B., Signor L., Proux O., Rovezzi M., Ciurli S., Cavazza C., Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), and Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG)

Subjects
Stereochemistry, Dimer, carbon monoxide dehydrogenase, enzymes, chemistry.chemical_element, 010402 general chemistry, 01 natural sciences, Catalysis, chemistry.chemical_compound, nickel, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, Binding site, nickel-binding cysteine, carbon monoxide dehydrogenases, chemistry.chemical_classification, biology, [SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Structural Biology [q-bio.BM], 010405 organic chemistry, Organic Chemistry, Rhodospirillum rubrum, CooT, General Chemistry, biology.organism_classification, [SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology, 0104 chemical sciences, Solvent, Nickel, enzyme, [SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biomolecules [q-bio.BM], Enzyme, chaperone protein, chemistry, biology.protein, Carbon monoxide dehydrogenase, Cysteine
Abstract

International audience; In Rhodospirillum rubrum, the maturation of carbon monoxide dehydrogenase (CODH) requires three nickel chaperones, namely RrCooC, RrCooT and RrCooJ. Recently, the biophysical characterization of RrCooT homodimer and the X‐ray structure of its apo‐form revealed the existence of a solvent exposed Ni(II)‐binding site at the dimer interface, involving the strictly conserved Cys2. Here, a multifaceted approach that used NMR and X‐ray absorption spectroscopies, complemented with structural bio‐modelling methodologies, was used to characterise the binding mode of Ni(II) in RrCooT. This study suggests that Ni(II) adopts a square‐planar geometry via a N2S2 coordinating environment that comprises the two thiolate and amidate groups of both Cys2 residues at the dimer interface. The existence of a diamagnetic mononuclear Ni(II) centre with bis‐amidate/bis‐thiolate ligands, coordinated by a single cysteine motif, is unprecedented in biology and raises the question of its role in the activation of CODH, at the molecular level.

Published
2019

50. Molecular epidemiology of enteroviruses from Guatemalan wastewater isolated from human lung fibroblasts.

Author

Sayyad L, Harrington C, Castro CJ, Belgasmi-Allen H, Jeffries Miles S, Hill J, Mendoza Prillwitz ML, Gobern L, Gaitán E, Delgado AP, Castillo Signor L, Rondy M, Rey-Benito G, and Gerloff N

Subjects
Humans, Guatemala epidemiology, Lung virology, Lung cytology, Molecular Epidemiology, Cell Line, Phylogeny, Animals, Poliovirus genetics, Poliovirus isolation & purification, Sewage virology, Mice, Enterovirus Infections virology, Enterovirus Infections epidemiology, Enterovirus genetics, Enterovirus isolation & purification, Wastewater virology, Fibroblasts virology
Abstract

The Global Specialized Polio Laboratory at CDC supports the Global Poliovirus Laboratory Network with environmental surveillance (ES) to detect the presence of vaccine strain polioviruses, vaccine-derived polioviruses, and wild polioviruses in high-risk countries. Environmental sampling provides valuable supplementary information, particularly in areas with gaps in surveillance of acute flaccid paralysis (AFP) mainly in children less than 15 years. In collaboration with Guatemala's National Health Laboratory (Laboratorio Nacional de Salud Guatemala), monthly sewage collections allowed screening enterovirus (EV) presence without incurring additional costs for sample collection, transport, or concentration. Murine recombinant fibroblast L-cells (L20B) and human rhabdomyosarcoma (RD) cells are used for the isolation of polioviruses following a standard detection algorithm. Though non-polio-Enteroviruses (NPEV) can be isolated, the algorithm is optimized for the detection of polioviruses. To explore if other EV's are present in sewage not found through standard methods, five additional cell lines were piloted in a small-scale experiment, and next-generation sequencing (NGS) was used for the identification of any EV types. Human lung fibroblast cells (HLF) were selected based on their ability to isolate EV-A genus. Sewage concentrates collected between 2020-2021 were isolated in HLF cells and any cytopathic effect positive isolates used for NGS. A large variety of EVs, including echoviruses 1, 3, 6, 7, 11, 13, 18, 19, 25, 29; coxsackievirus A13, B2, and B5, EV-C99, EVB, and polioviruses (Sabin 1 and 3) were identified through genomic typing in NGS. When the EV genotypes were compared by phylogenetic analysis, it showed many EV's were genomically like viruses previously isolated from ES collected in Haiti. Enterovirus occurrence did not follow a seasonality, but more diverse EV types were found in ES collection sites with lower populations. Using the additional cell line in the existing poliovirus ES algorithm may add value by providing data about EV circulation, without additional sample collection or processing. Next-generation sequencing closed gaps in knowledge providing molecular epidemiological information on multiple EV types and full genome sequences of EVs present in wastewater in Guatemala., Competing Interests: The authors have declared that no competing interests exist., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)

Published
2024
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