An improved synthesis of indazole-3-carboxylic acid

A new and efficient synthesis of indazole-3-carboxylic acid is reported. The method consists in reacting β-acetylphenylhydrazine with chloral hydrate and hydroxylamine hydrochloride in acidic medium to afford N-acetylaminoisonitrosoacetanilide which, in turn, is converted into the title compound by treatment with sulphuric acid.     

Synthesis,spectroscopic and magnetic characterization of some iron(III)-nucleotide compounds

Summary Magnetic moments and⁵⁷Fe M?ssbauer spectra at various temperatures of polycrystalline samples of some Fe^III-nucleotide compounds are described and have been characterized by u.v.-visible and fluorescence spectroscopy. Conclusions regarding the binding of iron(III) to nucleic acids are discussed.     

Coisotropic submanifolds in Poisson geometry and branes in the Poisson sigma model

General boundary conditions (branes') for the Poisson sigma model are studied. They turn out to be labeled by coisotropic submanifolds of the given Poisson manifold. The role played by these boundary conditions both at the classical and at the perturbative quantum level is discussed. It turns out to be related at the classical level to the category of Poisson manifolds with dual pairs as morphisms and at the perturbative quantum level to the category of associative algebras (deforming algebras of functions on Poisson manifolds) with bimodules as morphisms. Possibly singular Poisson manifolds arising from reduction enter naturally into the picture and, in particular, the construction yields (under certain assumptions) their deformation quantization.     

Femtosecond dynamics of Co thin films on Si support

The ultrafast electron and spin dynamics of Co films was investigated using a femto-second pump-probe technique. The samples were magnetically characterized by means of magnetooptical Kerr effect and non-optical magnetometers, i.e. superconductive quantum interference device and alternating gradient field magnetometer. Time evolution of both, Kerr rotation and ellipticity, was measured at different points of the static hysteresis cycle. This allowed separating magnetic and non-magnetic contributions to the signal. The sample magnetization was found to drop within 200 fs, following the pulse cross-correlation trace, while the magnetization recovery time was found to last few picoseconds.     

On Af.Af* geometries

This paper is intended to be a first step towards the classification of finite flag-transitive geometries of rank 3 with affine planes and dual affine point-residues. We describe those of diameter 1. In the case of diameter > 1, we describe minimal quotients, assuming that the number of lines through two points is large enough.     

Synthesis of an α‐amino nitrile and a bis α‐amino nitrile derivative of thiadiazole: reaction mechanism

The first nucleophilic addition of an inorganic nucleophile (cyanide) to the activated, rigid, α‐diazomethine groups of a 1,2,5‐thiadiazole 1,1‐dioxide is reported here. An α‐amino nitrile and a bis α‐amino nitrile derivatives were obtained in good yields (62 and 98%, respectively) and characterized by spectroscopic, analytical, and single crystal X‐ray diffraction techniques. The course of the reaction, followed by cyclic voltammetry (CV), showed that cyanide adds to only one of the two C?N double bonds of the thiadiazole, forming an anion from which an N‐methyl derivative was obtained. Adequate concentrations of cyanide and methyl iodide (MeI) produced directly the bis α‐amino nitrile derivative. Copyright © 2007 John Wiley & Sons, Ltd.     

Acoustic voice analysis in patients with Parkinson''s disease treated with dopaminergic drugs

To quantify several acoustic features of the voice in patients withParkinson's disease (PD), 41 patients and 28 age and sex-matched controls were studied. PD severity was assessed with the Unified PD Rating Scale (UPDRS) and the Hoehn and Yahr staging. The Computerized Speech Lab 4300 program (Kay Elemetrics) was used. Two seconds of a sustained /a/ and a sentence were captured with a microphone and laryngograph equipment. Measures included fundamental frequency (FO), frequency perturbation (fitter), intensity perturbation (shimmer), and harmonic/noise ratio (H/N) of the vowel /a/, and frequency and intensity variability of a sentence, phonational range, dynamic range at the natural frequency, maximum phonational time and s/z ratio. All subjects underwent indirect laryngoscopy and/or laryngeal fibroscopy. When compared with controls, PD patients showed higher jitter, lower H/N ratio, lower frequency and intensity variability of the sentence, and lower phonational range and reported a higher frequency of the presence of low voice-intensity, monopitch, voice arrests, and struggle. These features seem to be unaffected by the duration and severity of the disease.     

On the separation of split cuts and related inequalities

 The split cuts of Cook, Kannan and Schrijver are general-purpose valid inequalities for integer programming which include a variety of other well-known cuts as special cases. To detect violated split cuts, one has to solve the associated separation problem. The complexity of split cut separation was recently cited as an open problem by Cornuéjols & Li CL01. In this paper we settle this question by proving strong 𝒩𝒫-completeness of separation for split cuts. As a by-product we also show 𝒩𝒫-completeness of separation for several other classes of inequalities, including the MIR-inequalities of Nemhauser and Wolsey and some new inequalities which we call balanced split cuts and binary split cuts. We also strengthen 𝒩𝒫-completeness results of Caprara & Fischetti CF96 (for -cuts) and Eisenbrand E99 (for Chvátal-Gomory cuts). To compensate for this bleak picture, we also give a positive result for the Symmetric Travelling Salesman Problem. We show how to separate in polynomial time over a class of split cuts which includes all comb inequalities with a fixed handle. Received: October 23, 2000 / Accepted: October 03, 2001 Published online: September 5, 2002 Key words. cutting planes – separation – complexity – travelling salesman problem – comb inequalities