The North West Structural Genomics Centre's beamline, MAD10, at the SRS receives the central part of the radiation fan (0.5 mrad vertically, 4 mrad horizontally) produced by a new 2.46 T ten‐pole ...wiggler. The optical arrangement of the beamline consists of a Rh‐coated collimating Si mirror, a fixed‐exit‐beam double‐crystal monochromator with sagittal bending for horizontal focusing and a second Rh‐coated Si mirror for vertical focusing. The double‐crystal Si (111) monochromator allows data collection in the 5–13.5 keV photon energy range with rapid (subsecond) tunability and high energy resolution. The monochromatic beam is optimized through a 200 µm collimator. The beamline end station has been designed around a Mar desktop beamline with high‐throughput cryogenic sample changer, Mar225 CCD detector, liquid‐N2 autofill system and an ORTEC C‐TRAIN‐04 energy‐resolving high‐count‐rate X‐ray fluorescence detector. The instrument is optimized for MAD/SAD applications in protein crystallography with the additional mode of operation of online single‐crystal EXAFS studies on the same crystals. Thus, screening of metals/Se in the crystal can be performed quickly prior to MAD/SAD data collection by exciting the crystal with X‐rays of appropriate energy and recording an energy‐dispersive fluorescence spectrum. In addition, this experimental set‐up allows for parallel XAFS measurements on the same crystal to monitor `radiation‐induced' changes, if any, in e.g. the redox state of metal centres to be detected for a `metallic' functional group during crystallographic data collection. Moreover, careful minimization of the thickness of the Be window maximizes the intensity performance for the 2.0–2.5 Å softer wavelength range. This range also covers the K‐edges of a number of important 3d transition metals as well as the L‐edges of xenon and iodine and enhanced sulfur f ′′.
In this paper, we present a compiler testing technique that closes the gap between existing compiler implementations and correct compilers. Using formal specifications of procedure-calling ...conventions, we have built a target-sensitive test suite generator that builds test cases for a specific aspect of compiler code generators: the procedure-calling sequence generator. By exercising compilers with these specification-derived target-specific test suites, our automated testing tool has exposed bugs in every compiler tested on the MIPS and one compiler on the SPARC. These compilers include some that have been in heavy use for many years. Once a fault has been detected, the system can often suggest the nature of the problem. The testing system is an invaluable tool for detecting, isolating, and correcting faults in today's compilers.
An examination of the history of legal education covers the long period of law-office apprenticeship as the principal method of legal education in the United States and reviews trends in the period ...of formal education, the relationship between formal education and professional practice, the philosophical context for legal education, instruction in moral philosophy, and evolution of natural law theory.(MSE)
Branch elimination by condition merging Kreahling, William C.; Whalley, David; Bailey, Mark W. ...
Software, practice & experience,
01/2005, Letnik:
35, Številka:
1
Journal Article
The main use of synchrotron radiation facilities by protein crystallographers is to collect the best possible diffraction data for reasonably well defined problems. The process is therefore ...susceptible to automation. Significant effort throughout the world is therefore being given to automate SR protein crystallography facilities so scientists can obtain high throughput, even if they are not expert in all the techniques. Sample changers and automatic goniometers are being developed at various synchrotron sites and are also becoming available commercially. Tracking the various samples through the process is a significant issue. At the SRS we are taking a modular approach to automation, with a mixture of commercial products and in-house developments. Effort is required to integrate the various components but this approach gives the advantage that incremental upgrades can be made as new developments occur. A description of both the hardware and control software is given together with initial experience of the system. The developments are placed in the broader context of structure determination of proteins.
Building compilers that generate correct code is difficult. In this paper we present a compiler testing technique that closes the gap between actual compiler implementations and correct compilers. ...Using formal specifications of procedure calling conventions, we have built a target-sensitive test suite generator that builds test cases for a specific aspect of compiler code generators the procedure calling sequence generator. By exercising compilers with these target-specific test suites, our automated testing tool has exposed bugs in every compiler tested. These compilers include ones that have been in heavy use for many years. The detected bugs cause more than 14,000 test cases to fail.
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