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Tilo Beyer Gernot Schaller Michael Meyer-Hermann 《Computer Physics Communications》2005,172(2):86-108
A parallel algorithm for regular triangulations is presented. For the purpose of fully dynamic and kinetic particle simulations it allows vertex insertion, deletion, movement, and weight changes. We describe new algorithms for incremental construction of regular triangulations, parallel vertex deletion and insertion. Finally, a parallel Lawson flip algorithm for vertex displacements is presented. The performance analysis demonstrates a significant parallel efficiency for various system sizes and performed changes. 相似文献
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Matthias Engleder Dr. Tea Pavkov‐Keller Dr. Anita Emmerstorfer Altijana Hromic Sabine Schrempf Dr. Georg Steinkellner Dr. Tamara Wriessnegger Prof. Erich Leitner Dr. Gernot A. Strohmeier Dr. Iwona Kaluzna Dr. Daniel Mink Dr. Martin Schürmann Dr. Silvia Wallner Prof. Peter Macheroux Prof. Karl Gruber Dr. Harald Pichler 《Chembiochem : a European journal of chemical biology》2015,16(12):1730-1734
Hydratases provide access to secondary and tertiary alcohols by regio‐ and/or stereospecifically adding water to carbon‐carbon double bonds. Thereby, hydroxy groups are introduced without the need for costly cofactor recycling, and that makes this approach highly interesting on an industrial scale. Here we present the first crystal structure of a recombinant oleate hydratase originating from Elizabethkingia meningoseptica in the presence of flavin adenine dinucleotide (FAD). A structure‐based mutagenesis study targeting active site residues identified E122 and Y241 as crucial for the activation of a water molecule and for protonation of the double bond, respectively. Moreover, we also observed that two‐electron reduction of FAD results in a sevenfold increase in the substrate hydration rate. We propose the first reaction mechanism for this enzyme class that explains the requirement for the flavin cofactor and the involvement of conserved amino acid residues in this regio‐ and stereoselective hydration. 相似文献
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Franz Ferdinand Reinthaler Gebhard Feierl Herbert Galler Doris Haas Eva Leitner Franz Mascher Angelika Melkes Josefa Posch Ingrid Winter Gernot Zarfel Egon Marth 《Water research》2010,44(6):1981-1985
The aim of this study was to investigate the degree of contamination of sewage sludge with ESBL-producing Escherichia coli strains and the effectiveness of different sewage sludge treatment methods.Monthly sewage sludge samples were collected between January and September 2009 in 5 different sewage treatment plants and tested for the presence of ESBL E. coli. In addition, the number of colony forming units (CFU) of E. coli and coliform bacteria before and after the different sludge treatment methods (aerobic/anaerobic digestion, lime stabilization, and thermal treatment) was investigated.Of the 72 sewage sludge samples investigated, ESBL-positive E. coli were found in 44 (61.1%) sewage sludge samples. The classification of β-lactamase groups was carried out in 15 strains resulting in the detection of 2 different groups (CTX-M and TEM) of bla genes. All 15 of them had a CTX-M gene and 4 of these strains furthermore carried a TEM gene.With regard to the CFU of E. coli and coliform bacteria, thermal treatment and lime stabilization following dehydration sufficiently reduced pathogen concentrations. The plants using merely stabilization and dehydration showed an increase of E. coli and coliform bacteria and thus also an increase in ESBL-producing E. coli. 相似文献
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After slaughter, beef carcasses (n = 20) in groups of two were subjected to five treatments (one side only) including intermittent spray-chilling using water, 1% acetic acid or 1% lactic acid, or a single spray treatment with 1% acetic acid or 1% lactic acid. Intermittent spray-chilling consisted of two sprays of 30 s duration per hour for 12h. Single spray treatment consisted of one 30 s spray after entering the chill cooler. The other side of each carcass (control) was air chilled (at 2 to 3°C; air velocity 1 to 3 m/s) only. Five subprimal cuts were taken from each side at 48 h post mortem, vacuum packaged and stored for 28 days at 2°C. Intermittent sprays of sides with acetic or lactic acid resulted in significant (1.8-4.3 log/cm(2)) reductions in aerobic plate count of the strip loin, boneless rib and clod over their controls after these subprimal cuts had been vacuum packaged and stored for 28 days at 2°C in high-oxygen barrier (HOB) film. Lactobacillus spp. were dominant in the microflora of the subprimals from the control and treated sides. When sides were treated with a single sprays of acid, significant reductions in APC were noted only for some cuts of sides treated with lactic acid. After 28 days of storage, there were few significant differences in percentage purge, lean color, and off-odor scores between subprimals from control and treated sides. 相似文献
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