Nonlinear and non-separable multiscale representations based on Lipschitz perturbation

In this Note, we present a new formalism for nonlinear and non-separable multiscale representations. The new formalism we propose brings about similarities between existing nonlinear multiscale representations and also allows us to alleviate the classical hypotheses made to prove the convergence of the multiscale representations.     

Some remarks on non-commutative principal ideal rings

We prove some algebraic results on the ring of matrix differential operators over a differential field in the generality of non-commutative principal ideal rings. These results are used in the theory of non-local Poisson structures.     

Screening of pesticides in blood with liquid chromatography–linear ion trap mass spectrometry

In clinical or forensic toxicology, general unknown screening procedures are used to identify as many xenobiotics as possible, belonging to numerous chemical classes. We present here a general unknown screening procedure based on liquid chromatography coupled with use of a single linear ion trap mass spectrometer, and focus on the identification of pesticides and/or metabolites in whole blood. After solid-phase extraction (SPE), the compounds of interest were separated using a reversed-phase column and identified by the mass spectrometer operated first in the full-scan mass spectrometry (MS) mode, in the positive and negative polarities, followed by MS² and MS³ scanning of ions selected in data-dependent acquisition. The total scan time was 2.45 s. Two mass spectral libraries (MS² and MS³), each of 450 spectra, were created for the 320 pesticides and metabolites detected after injection of pure solutions. Robustness of the spectra and matrix effects were studied and were satisfactory for the present application. Detection limits for the 320 compounds were studied by extracting 1 mL spiked blood at concentrations between 10 μg/L and 10 mg/L. If necessary, it was possible to decrease the detection limits of some compounds by 10–100-fold by scanning MS² in only one polarity, owing to a shorter total scan time. However, at the same time, the detection specificity decreased as no confirmation could be recorded in the following MS³ scan and no information could be registered in the other polarity. So, in these rare cases, confirmation by another method was required.     

Incompact3d: A powerful tool to tackle turbulence problems with up to O(105) computational cores

Understanding the nature of complex turbulent flows remains one of the most challenging problems in classical physics. Significant progress has been made recently using high performance computing, and computational fluid dynamics is now a credible alternative to experiments and theories in order to understand the rich physics of turbulence. In this paper, we present an efficient numerical tool called Incompact3d that can be coupled with massive parallel platforms in order to simulate turbulence problems with as much complexity as possible, using up to O(10⁵) computational cores by means of direct numerical simulation (DNS). DNS is the simplest approach conceptually to investigate turbulence, featuring the highest temporal and spatial accuracy and it requires extraordinary powerful resources. This paper is an extension of Laizet et al.(Comput. Fluids 2010; 39 (3):471–484) where the authors proposed a strategy to run DNS with up to 1024 computational cores. Copyright © 2010 John Wiley & Sons, Ltd.     

On the Synthesis of Pyrrolobenzo[<Emphasis Type="Italic">b</Emphasis>]thieno[1,4]diazepines

Summary. 2-Amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile was converted into the corresponding 2-(pyrrol-1-yl) derivative, followed by reduction of the latter compound into the corresponding amine. This amine and its acyl, aroyl, and arylidene derivatives were used as synthons in the synthesis of several title compounds.     

Kinetic study of H‐atom transfer in imidazoline‐, imidazolidine‐, and pyrrolidine‐based alkoxyamines: Consequences for nitroxide‐mediated polymerization

The H‐atom transfer reaction was studied for a series of imidazoline, imidazolidine, and pyrrolidine‐based alkoxyamines containing either isobutyrate‐2‐yl or 1‐phenylethyl alkyl fragments. The C O bond homolysis rate constants and activation energies were determined by ¹H NMR product analysis as a function of temperature. Inter‐ and intramolecular H‐atom transfer reactions were distinguished by examination of alkoxyamine thermolysis products in the absence and in the presence of a radical scavenger (thiophenol or deuterated styrene). A correlation between the structure of the nitroxyl fragment of alkoxyamine and the H‐transfer reaction was found. The high steric demands of the substituents on the nitroxyl part of the isobutyrate‐2‐yl alkoxyamine decrease both types of reaction. For alkoxyamines containing the 1‐phenylethoxyamines, neither inter‐ nor intramolecular H‐atom transfer was observed. Controlled polymerization of methylmethacrylate initiated with imidazoline‐based alkoxyamine was observed, although the polymer obtained was not living. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6579–6595, 2009     

Recurrence and genericity

We prove a C¹-connecting lemma for pseudo-orbits of diffeomorphisms on compact manifolds. We explore some consequences for C¹-generic diffeomorphisms. For instance, C¹-generic conservative diffeomorphisms are transitive. To cite this article: C. Bonatti, S. Crovisier, C. R. Acad. Sci. Paris, Ser. I 336 (2003).     

Triangulations in CGAL

This paper presents the main algorithmic and design choices that have been made to implement triangulations in the computational geometry algorithms library .