Phase Diagram and Incommensurate Phases in Undoped Manganites

We study the existence of incommensurate phases in the phase diagram of the two orbital double exchange model coupled with Jahn-Teller phonons and with superexchange interactions. In agreement with experimental results, we find that undoped manganites $RMnO_3$ ($R$ being some rare earth element) show temperature induced commensurate-incommensurate phase transitions. In the incommensurate phase the magnetic wave vector varies with temperature. The incommensurate phase arises from the competition between the short range antiferromagnetic superexchange interaction and the long range ferromagnetic double exchange interaction

Involuntary admissions to the emergency department: a retrospective observational study.

The main objective of this study was to describe patients who were involuntarily admitted to the emergency department of Lausanne University Hospital on involuntary admission in 2018 in terms of age, gender, emergency department length of stay, the motive for involuntary admission, use of psychoactive substances, diagnosis, and destination at emergency department discharge, with or without discontinuation of involuntary admission. This retrospective, observational, and monocentric study included patients 18 years and older admitted to the emergency department of Lausanne University Hospital on involuntary admission from January 1, 2018, to December 31, 2018. Patients were identified by the Cantonal Medical Office of Vaud. The emergency department length of stay and patient destination on discharge from the emergency department were extracted from the patient flow database, and discharge letters and involuntary admission were extracted from the electronic archiving software. Descriptive statistics were processed by using means and standard deviations for quantitative variables with a normal distribution and median and interquartile range for non-normally distributed data. During the study period, 83 patients were admitted on involuntary admission to the emergency department. The majority of the patients were male (58%) with a mean age of 55 (±20) years. The median emergency department length of stay of patients with an involuntary admission was between 9 and 16 hours, depending on whether the involuntary admission was confirmed or discontinued after patient assessment in the emergency department. In comparison, the median emergency department length of stay was 6 hours for patients overall. The two principal diagnoses described were psychiatric (schizophrenia) and mental and behavioural disorders due to psychoactive substance use. Half of the patients on involuntary admission consumed psychoactive substances, primarily alcohol, and had a mean ethanolaemia of 53 (±32) mmol/l. Only a third of patients admitted on involuntary admission saw this measure confirmed after their assessment in the emergency department. Involuntary admissions with admission to the emergency department is used to force patients to be examined by an emergency physician or even a psychiatrist. On-call and primary care physicians seemed to lack the time or resources to set up alternatives to emergency department admissions on involuntary admission, especially in situations in which the involuntary admission was discontinued after an emergency department assessment. This demonstrates the inappropriate use of this measure because a patient cannot be involuntarily hospitalised in an emergency department

Fire debris analysis by Raman spectroscopy and chemometrics

A paper reporting the use of Raman Spectroscopy in fire debris analysis is presented. Five polymer based samples, namely carpet (polypropylene), nylon stockings (nylon), foam packaging (polystyrene), CD cases (polystyrene) and DVD cases (polypropylene) were burnt with each one of the following ignitable liquids: petrol, diesel, kerosene and ethanol. Raman shifts were obtained and, in some cases, peaks were identified to correspond to pyrolysis products in the form of alkanes, aromatic or polyaromatic compounds. All pyrolysis peaks were used to produce a Principal Component Analysis (PCA) of the burned samples with the different ignitable liquids. The change in the Raman spectra made it possible to identify some of the pyrolysis products produced in the combustion and also to identify the different plastic materials in fire debris, even when different fuels have been used and the chemical and structural identity of the plastic has been altered in the fire

Propagation of gamma rays and production of free electrons in air

A new concept of remote detection of concealed radioactive materials has been recently proposed \cite{Gr.Nusin.2010}-\cite{NusinSprangle}. It is based on the breakdown in air at the focal point of a high-power beam of electromagnetic waves produced by a THz gyrotron. To initiate the avalanche breakdown, seed free electrons should be present in this focal region during the electromagnetic pulse. This paper is devoted to the analysis of production of free electrons by gamma rays leaking from radioactive materials. Within a hundred meters from the radiation source, the fluctuating free electrons appear with the rate that may exceed significantly the natural background ionization rate. During the gyrotron pulse of about 10 microsecond length, such electrons may seed the electric breakdown and create sufficiently dense plasma at the focal region to be detected as an unambiguous effect of the concealed radioactive material.Comment: 27 pages, 10 figure

Lp-cohomology of negatively curved manifolds

We compute the $L^p$-cohomology spaces of some negatively curved manifolds. We deal with two cases: manifolds with finite volume and sufficiently pinched negative curvature, and conformally compact manifolds

Characterisation of precipitation upon cooling of an AA2618 Al-Cu-Mg alloy

The precipitation of an AA2618 Al-Cu-Mg alloy is monitored during isothermal holdings and continuous coolings. The Time-Temperature-Property and Continuous-Cooling-Precipitation diagrams of AA2618 are obtained using in-situ resistivity and differential scanning calorimetry respectively. The two precipitation domains observed at high temperature and low temperature (< 300 degrees C) are discussed with regard to their influence on the mechanical properties during quenching of large components. (C) 2015 Elsevier B.V. All rights reserved

Überinfusion von Verbrennungsopfern: häufig und schädlich

Zusammenfassung: Hintergrund: Schwerbrandverletzte (mehr als 20% verbrannter Körperoberfläche bei Erwachsenen) weisen in der ersten Phase (8-48h) einen durch das massive Kapillarleck bedingten Verbrennungsschock auf, der einer Infusionstherapie bedarf, um die Hämodynamik wieder herzustellen. Bis in die 80erJahre stellte eine unzureichende Flüssigkeitstherapie (Unterinfusion) die Haupttodesursache von Verbrennungspatienten dar. Seither ist die übermäßige Flüssigkeitstherapie (Überinfusion) zu einer beachtenswerten Quelle von Komplikationen geworden: abdominales Kompartmentsyndrom, Entlastungsschnitte (Escharotomie), Verschlechterung des Gasaustauschs, Verlängerung der künstlichen Beatmung und des Spitalaufenthalts. Die Überinfusion hat Ende der 90erJahre begonnen, wo innerhalb der ersten 24h Flüssigkeitsmengen zugeführt wurden, die weit über den 4ml/kg/%BSA ("burn surface area") der Parkland-Formel lagen. Ziel: Dieser Beitrag analysiert die Faktoren, welche zu einer Überinfusion führen können und zeigt Möglichkeiten, dem durch eine strikte Kontrolle der präklinischen Infusionstherapie sowie durch eine permissive Hypovolämie vorzubeuge

Dynamics of light propagation in spatiotemporal dielectric structures

Propagation, transmission and reflection properties of linearly polarized plane waves and arbitrarily short electromagnetic pulses in one-dimensional dispersionless dielectric media possessing an arbitrary space-time dependence of the refractive index are studied by using a two-component, highly symmetric version of Maxwell's equations. The use of any slow varying amplitude approximation is avoided. Transfer matrices of sharp nonstationary interfaces are calculated explicitly, together with the amplitudes of all secondary waves produced in the scattering. Time-varying multilayer structures and spatiotemporal lenses in various configurations are investigated analytically and numerically in a unified approach. Several new effects are reported, such as pulse compression, broadening and spectral manipulation of pulses by a spatiotemporal lens, and the closure of the forbidden frequency gaps with the subsequent opening of wavenumber bandgaps in a generalized Bragg reflector

Gupta–Bleuler Quantization of the Maxwell Field in Globally Hyperbolic Space-Times

We give a complete framework for the Gupta–Bleuler quantization of the free electromagnetic field on globally hyperbolic space-times. We describe one-particle structures that give rise to states satisfying the microlocal spectrum condition. The field algebras in the so-called Gupta–Bleuler representations satisfy the time-slice axiom, and the corresponding vacuum states satisfy the microlocal spectrum condition. We also give an explicit construction of ground states on ultrastatic space-times. Unlike previous constructions, our method does not require a spectral gap or the absence of zero modes. The only requirement, the absence of zero-resonance states, is shown to be stable under compact perturbations of topology and metric. Usual deformation arguments based on the time-slice axiom then lead to a construction of Gupta–Bleuler representations on a large class of globally hyperbolic space-times. As usual, the field algebra is represented on an indefinite inner product space, in which the physical states form a positive semi-definite subspace. Gauge transformations are incorporated in such a way that the field can be coupled perturbatively to a Dirac field. Our approach does not require any topological restrictions on the underlying space-time