BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Functionalisation of Self-Assembled Nanomaterials DTSTART;VALUE=DATE-TIME:20140519T235000Z DTEND;VALUE=DATE-TIME:20140520T001000Z DTSTAMP;VALUE=DATE-TIME:20260310T123732Z UID:indico-contribution-9-32@events01.synchrotron.org.au DESCRIPTION:Speakers: Cara Doherty (CSIRO)\nhttps://events01.synchrotron.o rg.au/event/0/contributions/32/ LOCATION:Australian Synchrotron URL:https://events01.synchrotron.org.au/event/0/contributions/32/ END:VEVENT BEGIN:VEVENT SUMMARY:Complementarity of small-angle x-ray and neutron scattering: solva tion effects and quaternary structure of proteins in solution DTSTART;VALUE=DATE-TIME:20140519T232000Z DTEND;VALUE=DATE-TIME:20140519T235000Z DTSTAMP;VALUE=DATE-TIME:20260310T123732Z UID:indico-contribution-9-30@events01.synchrotron.org.au DESCRIPTION:Speakers: Francesco Spinozzi (University of the Le Marche)\nSm all-angle X-ray (SAXS) and neutron (SANS) scattering are complementary tec hniques that are largely exploited to determine the structure of complex b iological macromolecules in solution\, such as proteins. Since solution pr oteins are randomly oriented particles\, the scattering signal is purely o ne-dimensional so that the basic challenge is to develop methods able to e xtract three-dimensional structures from experimental data. X-rays interac t with the electron clouds of each atom\, neutrons are scattered by atomic nuclei (with different power for the isotopes of the same element): a wis ely chosen combination of SAXS and SANS experiments on the same sample is a strategy to increase the structural information that can be derived from data analysis methods.\nTwo examples of the application of small-angle sc attering on protein structure investigation are shown. The first example i s a SANS study of the solvation properties of lysozyme dissolved in water/ glycerol mixtures (2). To make detectable the characteristics of protein-s olvent interface\, 35 different experimental conditions (i.e.\, protein co ncentration\, water/glycerol fraction in the solvent\, content of deuterat ed compounds) have been considered and fitted with a global fit approach. \nIn the second example the new QUAFIT method for determining the quaterna ry structure of proteins assemblies by analysing SAXS or SANS data is pres ented (2-3). The method is based on the idea that asymmetric monomers\, fo rmed by rigid domains of known atomic structure are assembled according to a point group symmetry combined with a screw axis. In order to avoid any overlap among domains\, the “contact distance” between two asymmetric domains is determined as a function of their orientation by a novel algori thm. QUAFIT has been applied to study the structure of hemocyanin from Oct opus vulgaris\, a high molecular weight protein that shows a particular se lf-assembling pattern\, characterized by a hierarchical organization of mo nomers. A dataset of SAXS and SANS curves has been recorded under differen t pH values\, buffer compositions\, H2O/D2O ratios and Hofmeister's salts. The structures of the decamer and of the dissociated “loose” monomer have been identified by analysing SAS curves in the most and the least agg regative conditions\, respectively. Afterwards\, all the other curves have been analysed through QUAFIT\, by considering heterogeneous mixtures comp osed of the entire decamer\, the dissociated “loose” monomer and all t he intermediate dissociation products.\n\n1) R. Sinibaldi\, M. G. Ortor e\, F. Spinozzi\, F. Carsughi\, H. Frielinghaus\, S. Cinelli\, G. Onori\, and P. Mariani\, J. Chem. Phys.\, 126:235101-235109\, 2007.\n2) F. Spin ozzi and M. Beltramini\, Biophys. J.\, 103:511–521\, 2012.\n3) F. Spi nozzi\, P. Mariani\, I. Mičetić\, C. Ferrero\, D. Pontoni\, and M. Beltr amini\, PLOS one\, e49644\, 2012.\n\nhttps://events01.synchrotron.org.au/e vent/0/contributions/30/ LOCATION:Australian Synchrotron URL:https://events01.synchrotron.org.au/event/0/contributions/30/ END:VEVENT BEGIN:VEVENT SUMMARY:Synchrotron radiation scattering methods for structural determinat ions on the nanoscale DTSTART;VALUE=DATE-TIME:20140520T003000Z DTEND;VALUE=DATE-TIME:20140520T010000Z DTSTAMP;VALUE=DATE-TIME:20260310T123732Z UID:indico-contribution-9-13@events01.synchrotron.org.au DESCRIPTION:Speakers: Sigrid Bernstorff (Elettra\, Trieste)\nSmall Angle X -ray Scattering (SAXS) is a well-established measurement tool that has bee n around for about 60 years. But the advent of modern third generation syn chrotron radiation sources in the early nineties has opened new possibilit ies for structural determinations on the nanoscale which were not possible in the past. The high brilliance of maschines like Elettra in Trieste all ows for fast time-resolved studies\, and permits also the investigation of materials that are very poor scatterers\, or are available only in small quantities.\n\nThe high-flux SAXS-beamline at ELETTRA has been designed sp ecifically for time-resolved diffraction on non-crystalline but partly ord ered samples like gels\, liquid crystals\, (bio)polymers\, amorphous mater ials\, muscles\, and proteins in solution. At e.g. 8 keV photon energy\, t he SAXS-resolution ranges from 1 to about 140 nm in d-spacing\, and the fl ux on the sample is up to 5x1012 photons/s. Simultaneously wide-angle diff raction measurements in the angular range of up to about 80o can be perfor med.\n\nAs an additional pre-requisite for time-resolved studies\, various techniques and instruments have been developed and implemented at the SAX S beamline to trigger transitions in samples with time resolutions down to the (sub-)ms regime. Possible parameters include temperature\, pressure\, shear\, mechanical stresses and chemical mixing. But the high brilliance is also advantageous in "static" SAXS experiments like scanning micro-spot applications (to study samples with high local spatial resolution down to 20 micron)\, or grazing incidence techniques like GISAXS\, GIXRD and Refl ectivity (to determine the structure of near-surface layers).\n\nAn overvi ew of recent technical developments and experimental results obtained at t he SAXS-beamline will be given for several representative sample systems.\ n\nhttps://events01.synchrotron.org.au/event/0/contributions/13/ LOCATION:Australian Synchrotron URL:https://events01.synchrotron.org.au/event/0/contributions/13/ END:VEVENT BEGIN:VEVENT SUMMARY:Quokka and food - Small-angle neutron scattering and discovering f ood structure at the nanoscale DTSTART;VALUE=DATE-TIME:20140520T001000Z DTEND;VALUE=DATE-TIME:20140520T003000Z DTSTAMP;VALUE=DATE-TIME:20260310T123732Z UID:indico-contribution-9-1@events01.synchrotron.org.au DESCRIPTION:Speakers: Elliot Gilbert (ANSTO)\nhttps://events01.synchrotron .org.au/event/0/contributions/1/ LOCATION:Australian Synchrotron URL:https://events01.synchrotron.org.au/event/0/contributions/1/ END:VEVENT END:VCALENDAR