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Resolution Data Set (resolution + data_set)
Selected AbstractsFinite element modelling of free-surface flows with non-hydrostatic pressure and k,, turbulence modelINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 2 2005C. Leupi Abstract Validation of 3D finite element model for free-surface flow is conducted using a high quality and high spatial resolution data set. The commonly numerical models with the conventional hydrostatic pressure still remain the most widely used approach for the solution of practical engineering problems. However, when a 3D description of the velocity field is required, it is useful to resort to a more accurate model in which the hydrostatic assumption is removed. The present research finds its motivation in the increasing need for efficient management of geophysical flows such as estuaries (multiphase fluid flow) or natural rivers with the presence of short waves and/or strong bathymetry gradient, and/or strong channel curvature. A numerical solution is based on the unsteady Reynolds-averaged Navier,Stokes equations on the unstructured grid. The eddy viscosity is calculated from the efficient k,, turbulence model. The model uses implicit fractional step time stepping, and the characteristics method is used to compute the convection terms in the multi-layers system (suitable for the vertical stratified fluid flow), in which the vertical grid is located at predefined heights and the number of elements in the water column depends on water depth. The bottommost and topmost elements of variable height allow a faithful representation of the bed and the time-varying free-surface, respectively. The model is applied to the 3D open channel flows of various complexity, for which experimental data are available for comparison. Computations with and without non-hydrostatic are compared for the same trench to test the validity of the conventional hydrostatic pressure assumption. Good agreement is found between numerical computations and experiments. Copyright © 2005 John Wiley & Sons, Ltd. [source] Development of a high resolution daily gridded temperature data set (1969,2005) for the Indian regionATMOSPHERIC SCIENCE LETTERS, Issue 4 2009A. K. Srivastava Abstract A high resolution daily gridded temperature data set for the Indian region was developed using temperature data of 395 quality controlled stations for the period 1969,2005. A modified version of the Shepard's angular distance weighting algorithm was used for interpolating the station temperature data into 1° latitude × 1° longitude grids. Using the cross validation, errors were estimated and found less than 0.5 °C. The data set was also compared with another high resolution data set and found comparable. Mean frequency of cold and heat waves, temperature anomalies associated with the monsoon breaks have been presented. Copyright © 2009 Royal Meteorological Society [source] Co-crystallization of Leptospira interrogans peptide deformylase with a potent inhibitor and molecular-replacement schemes with eight subunits in an asymmetric unitACTA CRYSTALLOGRAPHICA SECTION D, Issue 1 2004Peptide deformylase Translation initiation in eubacteria involves a formylmethionine at the N-terminus of newly synthesized polypeptides. This N-formyl group is removed by peptide deformylase (PDF) during the post-translation process. Such a formylation/deformylation cycle is essential for the cell survival of eubacteria, but is not utilized in eukaryotic cytosolic protein biosynthesis. In view of the absence of deformylase activity in mammalian cells, this is an attractive target for the design of novel antibiotic drugs. Co-crystallization of peptide deformylase from Leptospira interrogans (LiPDF) with its natural inhibitor actinonin produced diffraction-quality crystals that belong to space group P21, with unit-cell parameters a = 87.5, b = 119.1, c = 95.8,Å, , = 111.6°. The 3.1,Å resolution data set collected in-house was used to obtain phases by molecular replacement. Three schemes for the correction of the preliminary solutions were proposed and proved successful in determining the structure of LiPDF with eight subunits in the asymmetric unit. [source] Purification and crystallization of the respiratory complex formate dehydrogenase-N from Escherichia coliACTA CRYSTALLOGRAPHICA SECTION D, Issue 1 2002Mika Jormakka A membrane-protein complex, formate dehydrogenase-N from Escherichia coli, has been purified and crystallized. This molybdenum-containing enzyme, composed of ,, , and , subunits, is the major electron donor to the nitrate respiratory chain of E. coli. The formate dehydrogenase-N crystals belong to the cubic space group P213, with unit-cell parameters a = b = c = 203,Å. An asymmetric unit of the crystals is assumed to contain one formate dehydrogenase-N monomer (MW 170,kDa). One data set to 1.6,Å resolution, with 342,711 independent observations (94.4% complete) and an Rmerge of 0.08, has been collected from a single crystal. This is the highest resolution data set reported for a membrane-protein complex to date. [source] Crystallization and preliminary crystallographic studies of RhoGDI in complex with the radixin FERM domainACTA CRYSTALLOGRAPHICA SECTION D, Issue 6 2001Keisuke Hamada The Rho guanine nucleotide-dissociation inhibitor (RhoGDI) is a general regulator that forms a complex with the GDP-bound form of Rho-family GTPases and suppresses their activation. The FERM domains of ERM (ezrin/radixin/moesin) proteins bind to RhoGDI and dissociate Rho from RhoGDI. The formation of a complex between RhoGDI and the FERM domain is an important step in the regulatory cycle of Rho activation. In this study, crystals of RhoGDI complexed with the FERM domain of radixin were obtained. The crystals of the binary complex belong to the space group P21212, with unit-cell parameters a = 130.9,(2), b = 151.2,(2), c = 71.2,(1),Å, and contain two protein complexes in the crystallographic asymmetric unit. A 2.9,Å resolution data set was collected using synchrotron radiation at SPring-8. [source] Crystallization and preliminary X-ray crystallographic analysis of Lon from Thermococcus onnurineus NA1ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 1 2010Young Jun An Lon is an oligomeric ATP-dependent protease that degrades defective or denatured proteins as well as some folded proteins for the control of cellular protein quality and metabolism. Lon from Thermococcus onnurineus NA1 was purified and crystallized at 295,K. A 2.0,Å resolution data set was collected using synchrotron radiation. The crystals belonged to space group P63, with unit-cell parameters a = 121.45, b = 121.45, c = 195.24,Å. Assuming the presence of two monomers in the asymmetric unit, the solvent content was estimated to be about 60.7%. [source] Crystallization and preliminary X-ray crystallographic analysis of a novel histidinol-phosphate phosphatase from Thermococcus onnurineus NA1ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 5 2009Ha Il Jung The TON_0887 gene product from Thermococcus onnurineus NA1 is a 240-residue protein that has histidinol-phosphate phosphatase (HolPase) activity. According to analysis of its primary structure, the TON_0887 gene product is a monofunctional HolPase that belongs to the DDDD superfamily. This contrasts with the generally accepted classification that bifunctional HolPases belong to the DDDD superfamily. The TON_0887 gene product was purified and crystallized at 295,K. A 2.2,Å resolution data set was collected using synchrotron radiation. The TON-HolPase crystals belonged to space group P2221, with unit-cell parameters a = 40.88, b = 46.89, c = 148.03,Å. Assuming the presence of one molecule in the asymmetric unit, the solvent content was estimated to be about 48.3%. [source] Crystallization, diffraction data collection and preliminary crystallographic analysis of DING protein from Pseudomonas fluorescensACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 7 2007Sebastien Moniot PfluDING is a phosphate-binding protein expressed in Pseudomonas fluorescens. This protein is clearly distinct from the bacterial ABC transporter soluble phosphate-binding protein PstS and is more homologous to eukaryotic DING proteins. Interestingly, bacterial DING proteins have only been detected in certain Pseudomonas species. Although DING proteins seem to be ubiquitous in eukaryotes, they are systematically absent from eukaryotic genomic databases and thus are still quite mysterious and poorly characterized. PfluDING displays mitogenic activity towards human cells and binds various ligands such as inorganic phosphate, pyrophosphate, nucleotide triphosphates and cotinine. Here, the crystallization of PfluDING is reported in a monoclinic space group (P21), with typical unit-cell parameters a = 36.7, b = 123.7, c = 40.8,Å, , = 90, , = 116.7, , = 90°. Preliminary crystallographic analysis reveals good diffraction quality for these crystals and a 1.43,Å resolution data set has been collected. [source] Quantitative microscopy reveals 3D organization and kinetics of endocytosis in rat hepatocytesMICROSCOPY RESEARCH AND TECHNIQUE, Issue 9 2006Permsin Marbet Abstract In order to demonstrate the power of quantitative microscopy, the endocytic apparatus of rat hepatocytes was reexamined using in situ liver and short term cultured hepatocyte couplets that were allowed to internalize endocytic markers for various time intervals. Correlative confocal light and electron microscopy demonstrate a tubulovesicular reticulum representing the endocytic apparatus. Volume and membrane area account for 2% of cell volume and 30% plasma membrane surface. Colocalization analysis demonstrated that pathway-specific ligands and fluid-phase markers enter EEA1-positive vesicles, the early endosomal compartment, immediately after internalization. These vesicles are translocated rapidly from basolateral to perinuclear and apical locations. Ligands are sorted within 5 min to their respective pathways. Sequential colocalization of an asialoglycoprotein-pulse with rab7 and lamp3 demonstrates that early endosomes change into or fuse with late endosomes and lysosomes. Alternatively, markers are sequestered into the common endosome consisting of rab11-positive, long tubules that originate from early endosomes and show an affinity for the transcytotic marker pIgA and its receptor. This compartment mediates transcytosis by delivering the receptor,ligand complex to the subapical compartment, a set of apical, rab11-positive vesicles, which are connected to the tubular reticulum. We conclude that vesicular traffic between preexisting compartments, maturation or fusion of endocytic organelles, and transport in tubules act in concert and together mediate transport between compartments of a tubulovesicular endocytic apparatus. In addition, we show that quantitative microscopy using high resolution data sets can detect and characterize kinetics of various parameters thus adding a dynamic component to 3D information. Microsc. Res. Tech., 2006. © 2006 Wiley-Liss, Inc. [source] | ||||||||||