A deep X-ray observation of M82 with XMM-Newton

We report on the analysis of a deep (100 ks) observation of the starburst galaxy M82 with the EPIC and RGS instruments on board the X-ray telescope XMM-Newton. The broad-band (0.5-10 keV) emission is due to at least three spectral components: i) continuum emission from point sources; ii) thermal plasma emission from hot gas; iii) charge exchange emission from neutral metals (Mg and Si). The plasma emission has a double-peaked differential emission measure, with the peaks at ~0.5 keV and ~7 keV. Spatially resolved spectroscopy has shown that the chemical absolute abundances are not uniformly distributed in the outflow, but are larger in the outskirts and smaller close to the galaxy centre. The abundance ratios also show spatial variations. The X-ray derived Oxygen abundance is lower than that measured in the atmospheres of red supergiant stars, leading to the hypothesis that a significant fraction of Oxygen ions have already cooled off and no longer emit at energies > ~0.5 keV.Comment: Accepted for publication in MNRAS. 20 pages, 15 figures, LaTeX2

GPR research on damaged road pavements built in cut and fill sections

n/

Методика и методология социолингвистических исследований в условиях билингвизма и диглоссии

Lithospheric-scale analogue models are used to analyse the parameters controlling the typical evolution of deformation during continental narrow rifting, characterized by early activation of large boundary faults and basin subsidence, followed by localization of tectonic activity in internal faults at the rift axis. Integration of current and previous experiments shows that the evolution of deformation, in particular the amount of extension needed for the abandonment of boundary faults and migration of deformation to in-rift faults, is dependent on at least five boundary conditions: (i) thickness of brittle layers (including syn-rift sediments); (ii) thickness of ductile layers; (iii) extension rate; (iv) width of the weak zone localizing extension; and (v) rift obliquity with respect to the extension direction. An increase in the amount of extension corresponding to the inward migration of faulting (i.e., a longer phase of slip on boundary faults) is observed for (a) an increase in the thickness of both brittle and ductile crustal layers and syn-rift sediment accumulation, (b) a decrease in extension rate and width of the weak zone, and (c) a decrease in rift obliquity. A unified account of these correlations is presented, based on the hypothesis that fault migration occurs when boundary faults can no longer accommodate the imposed bulk extension, leading to time-space variations of internal strain and strain rate (and consequently stress) in the ductile layers which overcome the total resistance of brittle layers to thoroughgoing faulting

Stellar and gaseous abundances in M82

The near infrared (IR) absorption spectra of starburst galaxies show several atomic and molecular lines from red supergiants which can be used to infer reliable stellar abundances. The metals locked in stars give a picture of the galaxy metallicity prior to the last burst of star formation. The enrichment of the new generation of stars born in the last burst can be traced by measuring the hot gas in the X-rays. For the first time detailed stellar abundances in the nuclear region of the starburst galaxy M82 have been obtained. They are compared with those of the hot gas as derived from an accurate re-analysis of the XMM and Chandra nuclear X-ray spectra. The cool stars and the hot gas suggest [Fe/H]=-0.35+/-0.2 dex, and an overall [Si,Mg/Fe] enhancement by 0.4 and 0.5 dex, respectively. This is consistent with a major chemical enrichment by SNe II explosions in recursive bursts on short timescales. Oxygen is more puzzling to interpret since it is enhanced by 0.3 dex in stars and depleted by 0.2 dex in the hot gas. None of the standard enrichment scenarios can fully explain such a behavior when compared with the other alpha-elements.Comment: APJ, in pres

The Influence of Viscoelastic Crustal Rheologies on Volcanic Ground Deformation: Insights from Models of Pressure and Volume Change

This is the final version. Avaialble on open access from Wiley via the DOI in this recordInelastic rheological behaviour, such as viscoelasticity, is increasingly utilised in the modelling of volcanic ground deformation, as elevated thermal regimes induced by magmatic systems may necessitate the use of a mechanical model containing a component of time-dependent viscous behaviour. For the modelling of a given amplitude and footprint of ground deformation, incorporating a viscoelastic regime has been shown to reduce the magma reservoir overpressure requirements suggested by elastic models. This phenomenon, however, is restricted to pressure-based analyses and the associated creep behaviour. Viscoelastic materials exhibit additional constitutive time-dependent behaviours, determined by the stress and strain states, that are yet to be analysed in the context of volcanic ground deformation. By utilising a mechanically homogeneous model-space and distinct reservoir evolutions, we provide a comparison of three viscoelastic rheological models, including the commonly implemented Maxwell and Standard Linear Solid configurations, and their time-dependent behaviours from a fundamental perspective. We also investigate the differences between deformation timeseries resulting from a pressurisation or volume change; two contrasting approaches that are assumed to be equivalent through elastic modelling. Our results illustrate that the perceived influence of viscoelasticity is dependent on the mode of deformation, with stress-based pressurisation models imparting enhanced deformation relative to the elastic models, thus reducing pressure requirements. Strain-based volumetric models, however, exhibit reduced levels of deformation and may produce episodes of apparent ground subsidence induced by source inflation or vice versa, due to the relaxation of crustal stresses, dependent on whether the reservoir is modelled to be expanding or contracting, respectively.Natural Environment Research Council (NERC

Effects of a Combined Aquatic Exercise and Walking in Sedentary Obese Females Undergoing a Behavioral Weight-Loss Intervention

Background: The effects of the non-weight bearing method of aquatic exercise as a modality for weight loss have not been established. The purpose of this study was to examine the effects of a combined aquatic exercise and walking program compared to walking alone on body weight and selected variables in obese females undergoing a 16-week Standard Behavioral Treatment (SBT) program. Methods: Forty-four obese (BMI 34.9 ± 3.8 kg·m2) sedentary women (age=40.3 years ± 6.8 yrs) were randomly assigned to either an aquatic exercise (AE) group or a traditional walking (W) exercise only group. Both groups were also required to complete 3 sessions of home based walking per week, and reduce energy intake to facilitate weight loss. Results: In the AE group, total body weight, cardiorespiratory fitness, flexibility, strength, and health-related quality of life outcomes significantly improved over time similar to the W group. Significantly greater enjoyment scores also occurred in the AE group. Conclusion: Aquatic exercise in combination with walking can serve as an alternative to walking exercise alone for overweight women during periods of weight loss, and this can improve functional health status

Vascular anomalies of the celiac trunk and implications in treatment of HCC with TACE. Description of a case and review of the literature

Knowledge of the vascular anatomy of the upper abdomen is important in the daily practice of surgeons specialized in the hepatobiliary and pancreatic area, and for general surgeons and radiologists, mainly those involved in interventional radiology. Since anatomical variants of the celiac axis and hepatic arteries are common, an accurate description of vascularization is required before procedures to avoid iatrogenic vascular changes. We reported a case of a young male patient with HBV related cirrhosis, who came to our institution for the treatment of 2 HCC nodules. The preprocedural contrast-enhanced CT examination showed combined variations of celiac trunk, hepatic arteries, gastroduodenal artery, and right inferior phrenic artery. The careful pre- and intraprocedural evaluation of vascularization allowed us to perform transarterial chemoembolization of the 2 nodules without complications. The incidence and developmental and clinical significance of this variation is discussed with a detailed review of the literature. Knowledge of such a case has important clinical significance in abdominal operations or invasive arterial procedures

The Hot and Energetic Universe: Astrophysics of feedback in local AGN

Understanding the astrophysics of feedback in active galactic nuclei (AGN) is key to understanding the growth and co-evolution of supermassive black holes and galaxies. AGN-driven winds/outflows are potentially the most effective way of transporting energy and momentum from the nuclear scales to the host galaxy, quenching star formation by sweeping away the gas reservoir. Key questions in this field are: 1) how do accretion disks around black holes launch winds/outflows, and how much energy do these carry? 2) How are the energy and metals accelerated in winds/outflows transferred and deposited into the circumgalactic medium? X-ray observations are a unique way to address these questions because they probe the phase of the outflows which carries most of the kinetic energy. We show how a high throughput, high spectral resolution instrument like the X-ray Integral Field Unit (X-IFU) on Athena+ will allow us to address these questions by determining the physical parameters (ionization state, density, temperature, abundances, velocities, geometry, etc.) of the outflows on a dynamical time-scale, in a broad sample of nearby bright AGN. The X-IFU will also allow direct spectral imaging of the impact of these winds on the host galaxy for local AGN, forming a template for understanding AGN at higher redshifts where wind shocks cannot be resolved.Comment: Supporting paper for the science theme "The Hot and Energetic Universe" to be implemented by the Athena+ X-ray observatory (http://www.the-athena-x-ray-observatory.eu). 10 pages, 6 figure

Ultra-deep catalog of X-ray groups in the Extended Chandra Deep Field South

Ultra-deep observations of ECDF-S with Chandra and XMM-Newton enable a search for extended X-ray emission down to an unprecedented flux of $2\times10^{-16}$ ergs s$^{-1}$ cm$^{-2}$. We present the search for the extended emission on spatial scales of 32$^{\prime\prime}$ in both Chandra and XMM data, covering 0.3 square degrees and model the extended emission on scales of arcminutes. We present a catalog of 46 spectroscopically identified groups, reaching a redshift of 1.6. We show that the statistical properties of ECDF-S, such as logN-logS and X-ray luminosity function are broadly consistent with LCDM, with the exception that dn/dz/d$\Omega$ test reveals that a redshift range of $0.2<z<0.5$ in ECDF-S is sparsely populated. The lack of nearby structure, however, makes studies of high-redshift groups particularly easier both in X-rays and lensing, due to a lower level of clustered foreground. We present one and two point statistics of the galaxy groups as well as weak-lensing analysis to show that the detected low-luminosity systems are indeed low-mass systems. We verify the applicability of the scaling relations between the X-ray luminosity and the total mass of the group, derived for the COSMOS survey to lower masses and higher redshifts probed by ECDF-S by means of stacked weak lensing and clustering analysis, constraining any possible departures to be within 30% in mass. Abridged.Comment: 20 pages, 21 figures, 3 tables, to match the journal versio