Feedback by massive stars and the emergence of superbubbles. II. X-ray properties

This article has an erratum M. Krause, et al., “Feedback by massive stars and the emergence of superbubbles. II. X-ray properties”, Astronomy & Astrophysics, Vol. 566, June 2014. This version of record is available online at: https://www.aanda.org/articles/aa/abs/2014/06/aa23871-14/aa23871-14.html Reproduced with Permission from Astronomy and Astrophysics, © ESO 2014.Context. In a previous paper we investigated the energy transfer of massive stars to the interstellar medium (ISM) as a function of time and the geometrical configuration of three massive stars via 3D-mesh-refining hydrodynamics simulations, following the complete evolution of the massive stars and their supernovaewith the exception of non-thermal processes. Aims. To compare our results against observations we derivethermalX-ray properties of the ISM from our simulations and compare them to observations of superbubbles in general, to the well-studied nearby Orion-Eridanus superbubble and to the diffuse soft X-ray emission of nearby galaxies. Methods. We analysed our ISM simulation results with the help of spectra for plasma temperatures between 0.1 and 10 keV and computed the spectral evolution and the spatio-temporal distribution of the hot gas. Results. Despite significant input of high-temperature gas from supernovae and fast stellar winds, the resultingthermalX-ray spectra are generally very soft, with most of the emission well below 1 keV. We show that this is due to mixing triggered by resolved hydrodynamic instabilities. Supernovae enhance the X-ray luminosity of a superbubble by 1–2 orders of magnitude for a time span of about 0.1 Myr; which is longer if a supernova occurs in a larger superbubble and shorter in higher energy bands. Peak superbubble luminosities of the order of 1036 erg s-1 are reproduced well. The strong decay of the X-ray luminosity is due to bubble expansion, hydrodynamic instabilities related to the acceleration of the superbubble’s shell thanks to the sudden energy input, and subsequent mixing. We also find global oscillations of our simulated superbubbles, which produce spatial variations of the X-ray spectrum, similar to what we see in the Orion-Eridanus cavity. We calculated the fraction of energy emitted in X-rays and find that with a value of a few times 10-4, it is about a factor of ten below the measurements for nearby galaxies. Conclusions. Our models explain the observed soft spectra and peak X-ray luminosities of individual superbubbles. Each supernova event inside a superbubble produces a fairly similar heating-entrainment-cooling sequence, and the energy content of superbubbles is always determined by a specific fraction of the energy released by one supernova. For a given superbubble, soft X-rays trace the internal energy content well with moderate scatter. Some mechanism seems to delay the energy loss in real superbubbles compared to our simulations. Alternatively, some mechanism other thanthermal emission ofsuperbubbles may contribute to the soft X-ray luminosity of star-forming galaxies.Peer reviewe

Zum Zusammenhang von Geschlechterungleichheiten in Bildung, Beruf und Karriere : ein Ausblick

Ziel der folgenden Ausführungen im abschliessenden Teil dieses Sammelbands zur Entwicklung und Genese von geschlechtsspezifischen Bildungsungleichheiten ist es, den Blick zu öffnen in Richtung Berufsleben. Wie sind die verbesserten Bildungsmöglichkeiten von Frauen zu interpretieren? Ist es in den letzten Jahrzehnten gelungen, eines der grundlegendsten gesellschaftlichen Ungleichheitsverhältnisse zu beseitigen? Oder beginnt sich dieses sogar zu verkehren in eine gesellschaftliche Benachteiligung der Männer? Wir gehen bei unseren Überlegungen von der These aus, dass ein Abbau von Benachteiligungen der Frauen im Bildungssystem für sich genommen noch wenig aussagekräftig ist, wenn wir uns mit der klassischen soziologischen Frage der Persistenz bzw. des Wandels von gesellschaftlichen Ungleichheiten befassen wollen. Erst wenn die ganze Verknüpfung von Bildung und gesellschaftlicher Ungleichheit in den Blick genommen wird und sich dabei zeigt, dass Frauen ihre Bildungsgewinne auch in entsprechende Chancen im Beschäftigungssystem umsetzen können, sind ihre verbesserten Bildungschancen ein Gewinn für die Individuen und ein Fortschritt für die Gesellschaft – und erst dann könnten mögliche Bildungsvorteile von Frauen, wie sie in den vorliegenden Aufsätzen z.T. diagnostiziert werden, gar als neue gesellschaftliche Benachteiligungen von Männern skandalisiert werden

Working conditions and Work-Family Conflict in German hospital physicians: psychosocial and organisational predictors and consequences

<p>Abstract</p> <p>Background</p> <p>Germany currently experiences a situation of major physician attrition. The incompatibility between work and family has been discussed as one of the major reasons for the increasing departure of German physicians for non-clinical occupations or abroad. This study investigates predictors for one particular direction of Work-Family Conflict – namely work interfering with family conflict (WIF) – which are located within the psychosocial work environment or work organisation of hospital physicians. Furthermore, effects of WIF on the individual physicians' physical and mental health were examined. Analyses were performed with an emphasis on gender differences. Comparisons with the general German population were made.</p> <p>Methods</p> <p>Data were collected by questionnaires as part of a study on <it>Psychosocial work hazards and strains of German hospital physicians </it>during April–July 2005. Two hundred and ninety-six hospital physicians (response rate 38.9%) participated in the survey. The Copenhagen Psychosocial Questionnaire (COPSOQ), work interfering with family conflict scale (WIF), and hospital-specific single items on work organisation were used to assess WIF, its predictors, and consequences.</p> <p>Results</p> <p>German hospital physicians reported elevated levels of WIF (mean = 74) compared to the general German population (mean = 45, <it>p </it>< .01). No significant gender difference was found. Predictors for the WIF were lower age, high quantitative demands at work, elevated number of days at work despite own illness, and consequences of short-notice changes in the duty roster. Good sense of community at work was a protective factor. Compared to the general German population, we observed a significant higher level of quantitative work demands among hospital physicians (mean = 73 vs. mean = 57, <it>p </it>< .01). High values of WIF were significantly correlated to higher rates of personal burnout, behavioural and cognitive stress symptoms, and the intention to leave the job. In contrast, low levels of WIF predicted higher job satisfaction, better self-judged general health status, better work ability, and higher satisfaction with life in general. Compared to the German general population, physicians showed significantly higher levels of individual stress and quality of life as well as lower levels for well-being. This has to be judged as an alerting finding regarding the state of physicians' health.</p> <p>Conclusion</p> <p>In our study, work interfering with family conflict (WIF) as part of Work-Family Conflict (WFC) was highly prevalent among German hospital physicians. Factors of work organisation as well as factors of interpersonal relations at work were identified as significant predictors for WIF. Some of these predictors are accessible to alteration by improving work organisation in hospitals.</p

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Variation in the prices of oncology medicines across Europe and the implications for the future

Introduction/ Objectives: There are increasing concerns among health authorities regarding the sustainability of healthcare systems with growing expenditure on medicines including new high-priced oncology medicines. Medicine prices among European countries may be adversely affected by their population size and economic power to negotiate. There are also concerns that prices of patented medicines do not change once the prices of medicines used for negotiations substantially change. This needs to be investigated as part of the implications of low-cost generic oncology medicines. Methodology: Analysing principally reimbursed prices of patented oral oncology medicines (imatinib, erlotinib and fludarabine) between 2013 and 2017 across Europe and exploring correlations between GDP, population size, and prices. Comparing the findings with previous research regarding prices of oral generic oncology medicines. Results: The prices of imatinib, erlotinib and fludarabine did vary among European countries but showed limited price erosion over time in the absence of generics. There appeared to be no correlation between population size and prices. However, higher prices were seen among countries with higher GDP per capita which is a concern for lower income countries referencing these. Discussion and Conclusion: It is likely that the limited price erosion for patented oncology medicines will change across Europe with increased scrutiny over their prices and value as more medicines used for pricing decisions lose their patents combined with growing pressures on the oncology drug budget. In addition, discussions will continue regarding fair pricing for new oncology medicines and other approaches given ever rising prices with research showing substantial price reductions for oral oncology medicines (up to -97.8% for imatinib) once generics become available. We are also seeing appreciable price reductions for biosimilars further increasing the likelihood of these developments

Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

Search for heavy resonances decaying to two Higgs bosons in final states containing four b quarks

A search is presented for narrow heavy resonances X decaying into pairs of Higgs bosons (H) in proton-proton collisions collected by the CMS experiment at the LHC at root s = 8 TeV. The data correspond to an integrated luminosity of 19.7 fb(-1). The search considers HH resonances with masses between 1 and 3 TeV, having final states of two b quark pairs. Each Higgs boson is produced with large momentum, and the hadronization products of the pair of b quarks can usually be reconstructed as single large jets. The background from multijet and t (t) over bar events is significantly reduced by applying requirements related to the flavor of the jet, its mass, and its substructure. The signal would be identified as a peak on top of the dijet invariant mass spectrum of the remaining background events. No evidence is observed for such a signal. Upper limits obtained at 95 confidence level for the product of the production cross section and branching fraction sigma(gg -> X) B(X -> HH -> b (b) over barb (b) over bar) range from 10 to 1.5 fb for the mass of X from 1.15 to 2.0 TeV, significantly extending previous searches. For a warped extra dimension theory with amass scale Lambda(R) = 1 TeV, the data exclude radion scalar masses between 1.15 and 1.55 TeV

An embedding technique to determine ττ backgrounds in proton-proton collision data

An embedding technique is presented to estimate standard model tau tau backgrounds from data with minimal simulation input. In the data, the muons are removed from reconstructed mu mu events and replaced with simulated tau leptons with the same kinematic properties. In this way, a set of hybrid events is obtained that does not rely on simulation except for the decay of the tau leptons. The challenges in describing the underlying event or the production of associated jets in the simulation are avoided. The technique described in this paper was developed for CMS. Its validation and the inherent uncertainties are also discussed. The demonstration of the performance of the technique is based on a sample of proton-proton collisions collected by CMS in 2017 at root s = 13 TeV corresponding to an integrated luminosity of 41.5 fb(-1).Peer reviewe

Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at root s=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions

Peer reviewe