The Extreme Environment Diffractometer was a neutron time‐of‐flight instrument equipped with a constant‐field hybrid magnet providing magnetic fields up to 26 T. The magnet infrastructure and sample ...environment imposed limitations on the geometry of the experiment, making it necessary to plan the experiment with care. EXEQ is the software tool developed to allow users of the instrument to find the optimal sample orientation for their diffraction experiment. InEXEQ fulfilled the same role for the inelastic neutron scattering experiments. The source code of the software is licensed under the GNU General Public Licence 3, allowing it to be used by other facilities and adapted for use on other instruments.
EXEQ/InEXEQ software is a dedicated tool for single‐crystal orientation at the HFM‐EXED neutron scattering facility, and also a mandatory step of the proposal submission process.
The neutron time-of-flight spectrometer NEAT has a long history of successful applications and is best suited to probe dynamic phenomena directly in the large time domain 10−14 – 10−10 s and on the ...length scale ranging from 0.05 to up to about 5 nm. To address user community needs for more powerful instrumental capabilities, a concept of the full upgrade of NEAT has been proposed. The upgrade started in 2010 after a rigorous internal and external selection process and resulted in 300-fold neutron count rate increase compared to NEAT′1995. Combined with new instrumental and sample environmental capabilities the upgrade allows NEAT to maintain itself at the best world class level and provide an outstanding experimental tool for a broad range of scientific applications. The advanced features of the new instrument include an integrated guide-chopper system that delivers neutrons with flexible beam properties: either highly homogeneous beam with low divergence suitable for single crystals studies or “hot-spot” neutron distribution serving best small samples. Substantial increase of the detector angle coverage is achieved by using 416 3He position sensitive detectors. Placed at 3 m from the sample, the detectors cover 20 m2 area and are equipped with modern electronics and DAQ using event recording techniques. The installation of hardware has been completed in June 2016 and on January 23, 2017 NEAT has welcomed its first regular users who took advantage of the high counting rate, broad available range of incoming neutron wavelengths and high flexibility of NEAT. Here we present details of NEAT upgrade, measured instrument characteristics and show first experimental results.
Small‐angle scattering methods have become routine techniques for the structural characterization of macromolecules and macromolecular assemblies like polymers, (block) copolymers or micelles in the ...spatial range from a few to hundreds of nanometres. Neutrons are valuable scattering probes, because they offer freedom with respect to scattering length density contrast and isotopic labelling of samples. In order to gain maximum benefit from the allotted experiment time, the instrumental setup must be optimized in terms of statistics of scattered intensity, resolution and accessible range in momentum transfer Q. The new small‐angle neutron scattering instrument V16/VSANS at the Helmholtz‐Zentrum in Berlin, Germany, augments neutron guide collimation and pinhole optics with time‐of‐flight data recording and flexible chopper configuration. Thus, the available Q range and the respective instrumental resolution in the intermediate and high momentum transfer regions can be adjusted and balanced to the individual experimental requirements. This renders V16/VSANS a flexible and versatile instrument for soft‐matter research.
A measurement apparatus for observing the foaming of metals is described. It consists of a microfocus X‐ray source, a small heater and a panel detector. The foaming of samples can be recorded in ...real‐time with frequencies up to 9 Hz and resolutions down to 5 μm due to the small spot size. Magnifications up to 10x are obtained by simply changing the distance between source, sample and detector. Foaming of Al alloys and sandwiches was investigated applying different final foaming temperatures, heating rates and blowing agent pre‐treatments. An image analysis program was developed to automatically recognise the foam expansion.
A measurement apparatus for observing the foaming of metals is described. The foaming of samples can be recorded in real‐time with frequencies up to 9 Hz and resolutions down to 5 μm due to the small spot size. Magnifications up to 10× are obtained by simply changing the distance between source, sample and detector. Foaming of Al alloys and sandwiches was investigated and an image analysis program was developed to automatically recognise the foam expansion.
The neutron time-of-flight spectrometer NEAT has a long history of successful applications and is best suited to probe dynamic phenomena directly in the large time domain 10-14 – 10-10 s and on the ...length scale ranging from 0.05 to up to about 5 nm. To address user community needs for more powerful instrumental capabilities, a concept of the full upgrade of NEAT has been proposed. The upgrade started in 2010 after a rigorous internal and external selection process and resulted in 300-fold neutron count rate increase compared to NEAT'1995. Combined with new instrumental and sample environmental capabilities the upgrade allows NEAT to maintain itself at the best world class level and provide an outstanding experimental tool for a broad range of scientific applications. The advanced features of the new instrument include an integrated guide-chopper system that delivers neutrons with flexible beam properties: either highly homogeneous beam with low divergence suitable for single crystals studies or "hot-spot" neutron distribution serving best small samples. Substantial increase of the detector angle coverage is achieved by using 416 3He position sensitive detectors. Placed at 3 m from the sample, the detectors cover 20 m2 area and are equipped with modern electronics and DAQ using event recording techniques. The installation of hardware has been completed in June 2016 and on January 23, 2017 NEAT has welcomed its first regular users who took advantage of the high counting rate, broad available range of incoming neutron wavelengths and high flexibility of NEAT. Here we present details of NEAT upgrade, measured instrument characteristics and show first experimental results.
In this paper we present a software whiteboard for multimedia conferences. The whiteboard is specialised to load and share high-resolution colour images while using colour management functions to ...provide an accurate colour representation. The whiteboard is used in the telemedicine project INTER-FACE, which builds a virtual environment for tele-consultations between specialists in pre-operative treatment and the planning of the cranio-maxillofacial surgery for patients with facial abnormalities.
This paper presents the functionality and architecture of a new conference-control management system called Confman 2.0. It enables the user to initiate and participate in online conferences based on ...current Internet standards. Supported system platforms include Unix workstations and Microsoft operating systems as well. Starting with a short description of current Internet conferencing technology the paper describes Confman's conference-control functionality and gives a brief overview of Confman's distributed software architecture.
Phosphorylation is one of the most dynamic and widespread post‐translational modifications regulating virtually every aspect of eukaryotic cell biology. Here, we assemble a dataset from 75 ...independent phosphoproteomic experiments performed in our laboratory using Saccharomyces cerevisiae. We report 30,902 phosphosites identified from cells cultured in a range of DNA damage conditions and/or arrested in distinct cell cycle stages. To generate a comprehensive resource for the budding yeast community, we aggregate our dataset with the Saccharomyces Genome Database and another recently published study, resulting in over 46,000 budding yeast phosphosites. With the goal of enhancing the identification of functional phosphorylation events, we perform computational positioning of phosphorylation sites on available 3D protein structures and systematically identify events predicted to regulate protein complex architecture. Results reveal hundreds of phosphorylation sites mapping to or near protein interaction interfaces, many of which result in steric or electrostatic “clashes” predicted to disrupt the interaction. With the advancement of Cryo‐EM and the increasing number of available structures, our approach should help drive the functional and spatial exploration of the phosphoproteome.
SYNOPSIS
This study compiles a large set of independent experiments into a comprehensive phosphoproteome resource for the budding yeast community. 3D analysis of protein interaction interfaces and other strategies are used to predict functionality amongst the ≥ 40,000 reported phosphorylation events.
75 independent phosphoproteomic experiments were consolidated into a comprehensive resource of over 40,000 budding yeast phosphorylation sites.
Multiple strategies were used to infer functional phosphorylation events.
Mapping phosphorylation sites to protein interaction interfaces revealed phosphorylation sites that regulate protein‐protein interactions.
This study compiles 75 independent SILAC‐based experiments into a comprehensive phosphoproteome resource for budding yeast. 3D analysis of protein interaction interfaces and other strategies are used to predict functionality amongst the ≥ 40,000 reported phosphorylation events.
Ever since the first atomic structure of an enzyme was solved, the discovery of the mechanism and dynamics of reactions catalyzed by biomolecules has been the key goal for the understanding of the ...molecular processes that drive life on earth. Despite a large number of successful methods for trapping reaction intermediates, the direct observation of an ongoing reaction has been possible only in rare and exceptional cases.
Here, we demonstrate a general method for capturing enzyme catalysis "in action" by mix-and-inject serial crystallography (MISC). Specifically, we follow the catalytic reaction of the Mycobacterium tuberculosis β-lactamase with the third-generation antibiotic ceftriaxone by time-resolved serial femtosecond crystallography. The results reveal, in near atomic detail, antibiotic cleavage and inactivation from 30 ms to 2 s.
MISC is a versatile and generally applicable method to investigate reactions of biological macromolecules, some of which are of immense biological significance and might be, in addition, important targets for structure-based drug design. With megahertz X-ray pulse rates expected at the Linac Coherent Light Source II and the European X-ray free-electron laser, multiple, finely spaced time delays can be collected rapidly, allowing a comprehensive description of biomolecular reactions in terms of structure and kinetics from the same set of X-ray data.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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