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European Synchrotron Radiation Facility (european + synchrotron_radiation_facility)
Selected AbstractsX-ray Microtomography Analysis of Dynamic Damage in Tantalum,ADVANCED ENGINEERING MATERIALS, Issue 6 2006J. Bontaz-Carion With the plate-impact technique, ductile spallation experiments are carried out on Ta at impact velocities 570, 1039 and 1078 m/s. Samples are soft-recovered and analyzed by X-Ray microtomography at the European Synchrotron Radiation Facility. The porosity along the shock direction, and the distribution of the pore volumes are extracted from tri-dimensional reconstructions of the damaged samples. Quantitative assessment of pore coalescence is made via an inverse power-law model for the distribution. The decay exponent we associate to coalescence is of order 1.6 in the sample impacted at 1039 m/s. [source] Microarchitectural and Physical Changes During Fetal Growth in Human Vertebral Bone,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2003S Nuzzo Abstract The ossification process in human vertebra during the early stage of its formation was studied by X-ray diffraction (XRD) and X-ray microtomography (,CT) at the European Synchrotron Radiation Facility (ESRF), Grenoble, France. Twenty-two samples taken from vertebral ossification centers of human fetal bone (gestational age ranging between 16 and 26 weeks) were investigated. The analysis of three-dimensional images at high spatial resolution (,10 and ,2 ,m) allows a detailed quantitative description of bone microarchitecture. A denser trabecular network was found in fetal bone compared with that of adult bone. The images evidenced a global isotropic structure clearly composed of two regions: a central region (trabecular bone) and a peripheral region (immature bone). XRD experiments evidenced hydroxyapatite-like crystalline structure in the mineral phase at any fetal age after 16 weeks. Interestingly, the analysis of XRD patterns highlighted the evolution of crystalline structure of mineralized bone as a function of age involving the growth of the hydroxyapatite crystallites. [source] MxCuBE: a synchrotron beamline control environment customized for macromolecular crystallography experimentsJOURNAL OF SYNCHROTRON RADIATION, Issue 5 2010José Gabadinho The design and features of a beamline control software system for macromolecular crystallography (MX) experiments developed at the European Synchrotron Radiation Facility (ESRF) are described. This system, MxCuBE, allows users to easily and simply interact with beamline hardware components and provides automated routines for common tasks in the operation of a synchrotron beamline dedicated to experiments in MX. Additional functionality is provided through intuitive interfaces that enable the assessment of the diffraction characteristics of samples, experiment planning, automatic data collection and the on-line collection and analysis of X-ray emission spectra. The software can be run in a tandem client-server mode that allows for remote control and relevant experimental parameters and results are automatically logged in a relational database, ISPyB. MxCuBE is modular, flexible and extensible and is currently deployed on eight macromolecular crystallography beamlines at the ESRF. Additionally, the software is installed at MAX-lab beamline I911-3 and at BESSY beamline BL14.1. [source] Wavelength-dispersive spectrometer for X-ray microfluorescence analysis at the X-ray microscopy beamline ID21 (ESRF)JOURNAL OF SYNCHROTRON RADIATION, Issue 3 2010J. Szlachetko The development of a wavelength-dispersive spectrometer for microfluorescence analysis at the X-ray Microscopy ID21 beamline of the European Synchrotron Radiation Facility (ESRF) is reported. The spectrometer is based on a polycapillary optic for X-ray fluorescence collection and is operated in a flat-crystal geometry. The design considerations as well as operation characteristics of the spectrometer are presented. The achieved performances, in particular the energy resolution, are compared with the results of Monte Carlo simulations. Further improvement in the energy resolution, down to ,eV range, by employing a double-crystal geometry is examined. Finally, examples of applications requiring both spatial and spectral resolutions are presented. [source] Versatile vacuum chamber for in situ surface X-ray scattering studiesJOURNAL OF SYNCHROTRON RADIATION, Issue 4 2008Dina Carbone A compact portable vacuum-compatible chamber designed for surface X-ray scattering measurements on beamline ID01 of the European Synchrotron Radiation Facility, Grenoble, is described. The chamber is versatile and can be used for in situ investigation of various systems, such as surfaces, nanostructures, thin films etc., using a variety of X-ray-based techniques such as reflectivity, grazing-incidence small-angle scattering and diffraction. It has been conceived for the study of morphology and structure of semiconductor surfaces during ion beam erosion, but it is also used for the study of surface oxidation or thin film growth under ultra-high-vacuum conditions. Coherent X-ray beam experiments are also possible. The chamber is described in detail, and examples of its use are given. [source] New strepsirrhine primate from the late Eocene of Peninsular Thailand (Krabi Basin)AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2006Laurent Marivaux Abstract In this paper, we describe the newly discovered lower jaw of a primate from the late Eocene Krabi coal mine (Bang Mark pit) of Peninsular Thailand. We performed microtomographic examinations at the European Synchrotron Radiation Facility (ESRF, Grenoble, France) to analyze different morphological aspects of the jaw and teeth. Although partially preserved, this fossil mandible reveals a set of distinctive dental traits (e.g., double-rooted P2 and molarized P4) that allow us to describe a new stepsirrhine adapiform: Muangthanhinius siami, new genus and species. This taxon is somewhat atypical among Paleogene adapiforms, and more specialized than the sivaladapid adapiforms (hoanghoniines) that existed in Asia in the same epoch. In fact, Muangthanhinius shows a degree of dental specialization approximating that of some modern strepsirrhine lemuriforms, although it lacks the highly specialized anterior dentition characterizing this living primate group (canine + incisors forming a very procumbent toothcomb). In contrast, Muangthanhinius exhibits a large canine deeply anchored within the dentary that probably protruded high above the toothrow. Finally, despite the development of a molarized P4 as in Miocene sivaladapid sivaladapines, Muangthanhinius differs in molar morphology from this group, and the position of this new taxon within the Adapiformes remains indeterminate. Clarification of its phylogenetic position will require more morphological evidence than is currently available. Am J Phys Anthropol, 2006. © 2006 Wiley-Liss, Inc. [source] Purification, crystallization and preliminary structural studies of dTDP-4-keto-6-deoxy-glucose-5-epimerase (EvaD) from Amycolatopsis orientalis, the fourth enzyme in the dTDP- l -epivancosamine biosynthetic pathwayACTA CRYSTALLOGRAPHICA SECTION D, Issue 7 2002Alexandra B. Merkel The vancomycin class of antibiotics is regarded as the last line of defence against Gram-positive bacteria. The compounds used clinically are very complex organic molecules and are made by fermentation. The biosynthesis of these is complex and fascinating. Its study holds out the prospect of utilizing genetic engineering of the enzymes in the pathway in order to produce novel vancomycin analogues. In part, this requires detailed structural insight into substrate specificity as well as the enzyme mechanism. The crystallization of one of the enzymes in the chloroeremomycin biosynthetic pathway (a member of the vancomycin family), dTDP-3-amino-4-keto 2,3,6-trideoxy-3- C -methyl-glucose-5-epimerase (EvaD) from Amycolatopsis orientalis, is reported here. The protein is fourth in the pathway which makes a carbohydrate essential for the activity of chloroeremomycin. The crystals of EvaD diffract to 1.5,Å and have unit-cell parameters a = 98.6, b = 72.0, c = 57.1,Å with space group P21212. Data to this resolution were collected at the European Synchrotron Radiation Facility. [source] Crystallization and preliminary X-ray data of the recombinant peptide amidase from Stenotrophomonas maltophiliaACTA CRYSTALLOGRAPHICA SECTION D, Issue 2 2002Sebastian Neumann The peptide amidase from Stenotrophomonas maltophilia selectively hydrolyses the C-terminal amide bond in peptide amides. Crystals have been obtained by sitting-drop vapour diffusion from solution containing polyethylene glycol (PEG) 6000, HEPES pH 7.5, glycerine and sodium azide (NaN3). The crystals belong to the monoclinic space group P21, with unit-cell parameters a = 74.18, b = 62.60, c = 101.91,Å, , = 90°. X-ray data from these crystals diffracted at the European Synchrotron Radiation Facility (ESRF, France) ID14-1 beamline to 1.4,Å. [source] Crystallization and preliminary X-ray diffraction analysis of the dimerization domain of the tumour suppressor ING4ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 5 2010Simone Culurgioni Inhibitor of growth protein 4 (ING4) belongs to the ING family of tumour suppressors and is involved in chromatin remodelling, in growth arrest and, in cooperation with p53, in senescence and apoptosis. Whereas the structure and histone H3-binding properties of the C-terminal PHD domains of the ING proteins are known, no structural information is available for the N-terminal domains. This domain contains a putative oligomerization site rich in helical structure in the ING2,5 members of the family. The N-terminal domain of ING4 was overexpressed in Escherichia coli and purified to homogeneity. Crystallization experiments yielded crystals that were suitable for high-resolution X-ray diffraction analysis. The crystals belonged to the orthorhombic space group C222, with unit-cell parameters a = 129.7, b = 188.3, c = 62.7,Å. The self-rotation function and the Matthews coefficient suggested the presence of three protein dimers per asymmetric unit. The crystals diffracted to a resolution of 2.3,Å using synchrotron radiation at the Swiss Light Source (SLS) and the European Synchrotron Radiation Facility (ESRF). [source] Crystallization and preliminary X-ray characterization of a catalytic and ATP-binding domain of a putative PhoR histidine kinase from the ,-radioresistant bacterium Deinococcus radioduransACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 4 2010S. Caria The gene product of histidine kinase DR2244 (putative phoR) encoded by Deinococcus radiodurans has been suggested to be involved in the PhoR,PhoB two-component regulatory system. This two-component signalling system is activated upon phosphate starvation in several bacteria, including D. radiodurans. Single crystals were obtained from a recombinant preparation of the catalytic/ATP-binding (CA) domain of D. radiodurans PhoR (79,224) overexpressed in Escherichia coli. The crystals belonged to space group P212121, with unit-cell parameters a = 46.9, b = 81.8, c = 204.6,Å. The crystals contained six molecules in the asymmetric unit. Diffraction data were collected to 2.4,Å resolution on beamline ID23-2 of the European Synchrotron Radiation Facility. [source] Crystallization and preliminary X-ray characterization of a glycerol dehydrogenase from the human pathogen Salmonella enterica serovar TyphimuriumACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 7 2009A. T. Gonçalves Glycerol dehydrogenase (GldA) encoded by the STM4108 gene (gldA) has been related to the synthesis of HilA, a major transcriptional regulator that is responsible for the expression of invasion genes in the human pathogen Salmonella enterica serovar Typhimurium. Single colourless crystals were obtained from a recombinant preparation of GldA overexpressed in Escherichia coli. They belonged to space group P2221, with unit-cell parameters a = 127.0, b = 160.1, c = 665.2,Å. The crystals contained a very large number of molecules in the asymmetric unit, probably 30,35. Diffraction data were collected to 3.5,Å resolution using synchrotron radiation at the European Synchrotron Radiation Facility. [source] Crystallization and preliminary X-ray characterization of 1,3-propanediol dehydrogenase from the human pathogen Klebsiella pneumoniaeACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 3 2007D. Marçal 1,3-Propanediol dehydrogenase (1,3-PD-DH), encoded by the dhaT gene, is a key enzyme in the dissimilation process for converting glycerol to 1,3-propanediol in the human pathogen Klebsiella pneumoniae. Single colourless crystals were obtained from a recombinant preparation of 1,3-propanediol dehydrogenase overexpressed in Escherichia coli. The crystals belong to space group P21, with unit-cell parameters a = 91.9, b = 226.6, c = 232.6,Å, , = 92.9°. The crystals probably contain two decamers in the asymmetric unit, with a VM value of 3.07,Å3,Da,1 and an estimated solvent content of 59%. Diffraction data were collected to 2.7,Å resolution using synchrotron radiation at the ID14-4 beamline of the European Synchrotron Radiation Facility. [source] Achievements in high-pressure science at the high-brilliance energy-dispersive X-ray absorption spectrometer of ESRF, ID24JOURNAL OF SYNCHROTRON RADIATION, Issue 6 2009Giuliana Aquilanti Although the idea of an X-ray absorption spectrometer in dispersive geometry was initially conceived for the study of transient phenomena, the instrument at the European Synchrotron Radiation facility has been increasingly exploited for studies at extreme conditions of pressure using diamond anvil cells. The main results of investigations at high pressure obtained at beamline ID24 are reviewed. These concern not only fundamental topics, such as the local and the electronic structure as well as the magnetic properties of matter, but also geological relevant questions such as the behaviour of Fe in the main components of the Earth's interior. 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