Local topological modification of hexahedral meshes. Part I: A set of dual-based operations

For hexahedral meshes, it is difficult to make topological modifications which preserve conformal property and which are local to the modified elements. This is most easily understood in how changes affect the dual surfaces (sheets) and lines (chords), which have non-local extent in hexahedral meshes. A set of three operations is proposed which represent distinct local changes to the hex mesh and its dual. These operations are shown to compose the larger set of (lipping) operations described by Bern et. al. The relation between these dual-based operations and the insertion of a Boy surface in the dual, described by Bern, is also discussed

Stimulation of transient elevations in cytosolic Ca\u3csup\u3e2+\u3c/sup\u3e is related to inhibition of P(i) transport in OK cells

Stimulation of changes in cytosolic free calcium by parathyroid hormone was determined in three opossum kidney (OK) cell types, OK wild-type, OKP clone, and OKH clone. All three types of OK cells express parathyroid hormone (PTH)-sensitive adenylate cyclase and adenosine 3\u27,5\u27-cyclic monophosphate (cAMP) production. However, only the OK wild-type and the OKP clone respond to PTH with inhibition of sodium-dependent P(i) transport and transient increases in cytosolic calcium. Characterization of the increases in cytosolic calcium in the wild-type and OKP clones revealed they were due in part to stimulation of Ca2+ release from intracellular stores, probably by inositol 1,4,5-trisphosphate (IP3), which was stimulated by PTH. PTH-stimulated Ca2+ transients were also inhibited by protein kinase C activation. These data are compatible with PTH receptor-mediated phospholipase C activation and its feedback inhibition by protein kinase C. The OKH cells demonstrated a slow increase in cytosolic calcium when stimulated by cyclic nucleotides but no evidence for PTH stimulation of Ca2+ release from intracellular stores. Thus the absence of an inhibitory response of sodium-dependent P(i) transport to PTH in the OKH cells is associated with the absence of the rapid transient elevations of cytosolic Ca2+ such as those produced by IP3 production. These data suggest an important cooperative role for cAMP and the phospholipase C-stimulated Ca2+-protein kinase C message system in the regulation of P(i) transport

Local Topological Modification of Hexahedral Meshes Part II: Combinatorics and Relation to Boy Surface

Hexahedral meshes are structured as a set of ordered layer of hexes which makes local topological modifications difficult to do. For instance, removing an hex generally implies to remove a complete layer of hexes. Few works focus on local topological modifications in hexahedral meshes. In this paper, we provide some results which extend and complete some existing works [1,14,15,17], proving in a first part that the flipping operations defined by M. Ber

Differentiation of Staphylococcus argenteus (formerly: Staphylococcus aureus clonal complex 75) by mass spectrometry from S. aureus using the first strain isolated from a wild African great ape

The species Staphylococcus argenteus was separated recently from Staphylococcus aureus (Tong S.Y., F. Schaumburg, M.J. Ellington, J. Corander, B. Pichon, F. Leendertz, S.D. Bentley, J. Parkhill, D.C. Holt, G. Peters, and P.M. Giffard, 2015). The objective of this work was to characterise the genome of a non-human S. argenteus strain, which had been isolated from the faeces of a wild-living western lowland gorilla in Gabon, and analyse the spectrum of this species in matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The full genome sequence revealed a scarcity of virulence genes and absence of resistance genes, indicating a decreased virulence potential compared to S. aureus and the human methicillin-resistant S. argenteus isolate MSHR1132T. Spectra obtained by MALDI-TOF MS and the analysis of available sequences in the genome databases identified several MALDI-TOF MS signals that clearly differentiate S. argenteus, the closely related Staphylococcus schweitzeri and S. aureus. In conclusion, in the absence of biochemical tests that identify the three species, mass spectrometry should be employed as method of choice.This work was supported by a grant of the Deutsches Zentrum für Infektionsforschung (DZIF) to Gabriele Bierbaum (TTU 08.902) and the Fundação para a Ciência e a Tecnologia (FCT) to Luís D.R. Melo (SFRH/BD/66166/2009) as well as by the BONFOR funds of the Medical Faculty of the University of Bonn and funds of the Centre International de Recherches Médicales de Franceville (CIRMF) and the Institut de Recherche pour le Développement (IRD)