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Dieter Schütt† 《控制论与系统》2013,44(4):69-73
Abstract This note completes the author's study of embedding of cascade products of permutation or reset automata in so-called shift register graphs. 相似文献
105.
The potential of industrial porous concrete for using as a template for the synthesis of porous carbon materials has been investigated. Carbon replicas of porous concrete have been prepared by carbonization of sucrose. The pores of the resulting carbon materials range from the macropore to the micropore region, pointing to a hierarchy. 相似文献
106.
Assessment of intradialysis calcium mass balance by a single pool variable‐volume calcium kinetic model
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Salvatore di Filippo Fabio Carfagna Vincenzo la Milia Antonio Bellasi Giustina Casagrande Camilla Bianchi Domenico Vito Maria Laura Costantino Giuseppe Rombolà Claudio Minoretti Carlo Schönholzer Giuseppe Pontoriero Francesco Locatelli 《Hemodialysis international. International Symposium on Home Hemodialysis》2018,22(1):126-135
Introduction: A reliable method of intradialysis calcium mass balance quantification is far from been established. We herein investigated the use of a single‐pool variable‐volume Calcium kinetic model to assess calcium mass balance in chronic and stable dialysis patients. Methods: Thirty‐four patients on thrice‐weekly HD were studied during 240 dialysis sessions. All patients were dialyzed with a nominal total calcium concentration of 1.50 mmol/L. The main assumption of the model is that the calcium distribution volume is equal to the extracellular volume during dialysis. This hypothesis is assumed valid if measured and predicted end dialysis plasma water ionized calcium concentrations are equal. A difference between predicted and measured end‐dialysis ionized plasma water calcium concentration is a deviation on our main hypothesis, meaning that a substantial amount of calcium is exchanged between the extracellular volume and a nonmodeled compartment. Findings: The difference between predicted and measured values was 0.02 mmol/L (range ?0.08:0.16 mmol/L). With a mean ionized dialysate calcium concentration of 1.25 mmol/L, calcium mass balance was on average negative (mean ± SD ?0.84 ± 1.33 mmol, range ?5.42:2.75). Predialysis ionized plasma water concentration and total ultrafiltrate were the most important predictors of calcium mass balance. A significant mobilization of calcium from the extracellular pool to a nonmodeled pool was calculated in a group of patients. Discussion: The proposed single pool variable‐volume Calcium kinetic model is adequate for prediction and quantification of intradialysis calcium mass balance, it can evaluate the eventual calcium transfer outside the extracellular pool in clinical practice. 相似文献
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Dr. Aline Telzerow Dr. Juraj Paris Dr. Maria Håkansson Dr. Javier González-Sabín Dr. Nicolas Ríos-Lombardía Prof. Dr. Harald Gröger Dr. Francisco Morís Dr. Martin Schürmann Prof. Dr. Helmut Schwab Dr. Kerstin Steiner 《Chembiochem : a European journal of chemical biology》2021,22(7):1232-1242
Amine transaminases (ATAs) are used to synthesize enantiomerically pure amines, which are building blocks for pharmaceuticals and agrochemicals. R-selective ATAs belong to the fold type IV PLP-dependent enzymes, and different sequence-, structure- and substrate scope-based features have been identified in the past decade. However, our knowledge is still restricted due to the limited number of characterized (R)-ATAs, with additional bias towards fungal origin. We aimed to expand the toolbox of (R)-ATAs and contribute to the understanding of this enzyme subfamily. We identified and characterized four new (R)-ATAs. The ATA from Exophiala sideris contains a motif characteristic for d -ATAs, which was previously believed to be a disqualifying factor for (R)-ATA activity. The crystal structure of the ATA from Shinella is the first from a Gram-negative bacterium. The ATAs from Pseudonocardia acaciae and Tetrasphaera japonica are the first characterized (R)-ATAs with a shortened/missing N-terminal helix. The active-site charges vary significantly between the new and known ATAs, correlating with their diverging substrate scope. 相似文献
108.
R. Schönfelder M. Knupfer J.A. Azamar-Barrios P.I. González-Chi M.H. Rümmeli 《Journal of Experimental Nanoscience》2014,9(9):931-941
Raman spectroscopy was used to characterise 11 varieties of carbon nanostructures (CNSs) consisting on seven varieties of commercial multi-walled carbon nanotubes, two types of carbon nanofibres and two types of lab-synthesised single-walled carbon nanotubes. The Raman spectra of these CNSs provided information on the structural ordering of the as-received (or as-synthesised) material. Additionally, the CNSs were chemically treated by two mixtures of nitric and sulphuric acids at markedly different concentrations and then characterised by Raman spectroscopy. The features of the G and D Raman bands of the CNSs were used to assess structural modifications and generation of defects induced by the acid treatments. Changes in the Raman spectra before and after acidic treatment depend strongly on the initial intensity ratio of the G to D bands and the architecture (number of layers or diameter) of the CNSs. 相似文献
109.
Klaus Kaiser Jochen Schütz Ruth Schöbel Sebastian Noelle 《Journal of scientific computing》2017,70(3):1390-1407
In this work, we propose a new way of splitting the flux function of the isentropic compressible Euler equations at low Mach number into stiff and non-stiff parts. Following the IMEX methodology, the latter ones are treated explicitly, while the first ones are treated implicitly. The splitting is based on the incompressible limit solution, which we call reference solution. An analysis concerning the asymptotic consistency and numerical results demonstrate the advantages of this splitting. 相似文献