8 research outputs found

    Multiwavelength behaviour of the blazar 3C 279: decade-long study from γ-ray to radio

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    We report the results of decade-long (2008–2018) Îł-ray to 1 GHz radio monitoring of the blazar 3C 279, including GASP/WEBT, Fermi and Swift data, as well as polarimetric and spectroscopic data. The X-ray and Îł-ray light curves correlate well, with no delay ≳ 3 h, implying general cospatiality of the emission regions. The Îł-ray–optical flux–flux relation changes with activity state, ranging from a linear to a more complex dependence. The behaviour of the Stokes parameters at optical and radio wavelengths, including 43 GHz Very Long Baseline Array images, supports either a predominantly helical magnetic field or motion of the radiating plasma along a spiral path. Apparent speeds of emission knots range from 10 to 37c, with the highest values requiring bulk Lorentz factors close to those needed to explain Îł-ray variability on very short time-scales. The Mg ii emission line flux in the ‘blue’ and ‘red’ wings correlates with the optical synchrotron continuum flux density, possibly providing a variable source of seed photons for inverse Compton scattering. In the radio bands, we find progressive delays of the most prominent light-curve maxima with decreasing frequency, as expected from the frequency dependence of the τ = 1 surface of synchrotron self-absorption. The global maximum in the 86 GHz light curve becomes less prominent at lower frequencies, while a local maximum, appearing in 2014, strengthens toward decreasing frequencies, becoming pronounced at ∌5 GHz. These tendencies suggest different Doppler boosting of stratified radio-emitting zones in the jet.First author draf

    Towards better definition, quantification and treatment of fibrosis in heart failure. A scientific roadmap by the Committee of Translational Research of the Heart Failure Association (HFA) of the European Society of Cardiology

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    Fibrosis is a pivotal player in heart failure development and progression. Measurements of (markers of) fibrosis in tissue and blood may help to diagnose and risk stratify patients with heart failure, and its treatment may be effective in preventing heart failure and its progression. A lack of pathophysiological insights and uniform definitions has hampered the research in fibrosis and heart failure. The Translational Research Committee of the Heart Failure Association discussed several aspects of fibrosis in their workshop. Early insidious perturbations such as subclinical hypertension or inflammation may trigger first fibrotic events, while more dramatic triggers such as myocardial infarction. and myocarditis give rise to full blown scar formation and ongoing fibrosis in diseased hearts. Aging itself is also associated with a cardiac phenotype that includes fibrosis. Fibrosis is an extremely heterogeneous phenomenon, as several stages of the fibrotic process exist, each with different fibrosis subtypes and a different composition of various cells and proteins — resulting in a very complex pathophysiology. As a result, detection of fibrosis, e.g. using current cardiac imaging modalities or plasma biomarkers, will detect only specific subforms of fibrosis, but cannot capture all aspects of the complex fibrotic process. Furthermore, several anti-fibrotic therapies are under investigation, but such therapies generally target aspecific aspects of the fibrotic process and suffer from a lack of precision. This review discusses the mechanisms and the caveats and proposes a roadmap for future research. © 2019 The Authors. European Journal of Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology

    Towards better definition, quantification and treatment of fibrosis in heart failure. A scientific roadmap by the Committee of translational research of the heart failure association (HFA) of the european society of cardiology

    No full text
    Fibrosis is a pivotal player in heart failure development and progression. Measurements of (markers of) fibrosis in tissue and blood may help to diagnose and risk stratify patients with heart failure, and its treatment may be effective in preventing heart failure and its progression. A lack of pathophysiological insights and uniform definitions has hampered the research in fibrosis and heart failure. The Translational Research Committee of the Heart Failure Association discussed several aspects of fibrosis in their workshop. Early insidious perturbations such as subclinical hypertension or inflammation may trigger first fibrotic events, while more dramatic triggers such as myocardial infarction and myocarditis give rise to full blown scar formation and ongoing fibrosis in diseased hearts. Aging itself is also associated with a cardiac phenotype that includes fibrosis. Fibrosis is an extremely heterogeneous phenomenon, as several stages of the fibrotic process exist, each with different fibrosis subtypes and a different composition of various cells and proteins - resulting in a very complex pathophysiology. As a result, detection of fibrosis, e.g. using current cardiac imaging modalities or plasma biomarkers, will detect only specific subforms of fibrosis, but cannot capture all aspects of the complex fibrotic process. Furthermore, several anti-fibrotic therapies are under investigation, but such therapies generally target aspecific aspects of the fibrotic process and suffer from a lack of precision. This review discusses the mechanisms and the caveats and proposes a roadmap for future research

    The socialist past and post-socialist urban identity in Central and Eastern Europe

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    Cities in Central and Eastern Europe (CEE) are creating new urban identities under conditions of postsocialist transformation, Europeanization and globalization. Discourses about postsocialist urban identity frequently attempt to `Europeanize' these cities' identity and to obscure elements of the `unwanted past', particularly the socialist, Soviet and Russian pasts. However, those pasts can return to disrupt dominant narratives of postsocialist urban identity. This article analyses how the past of socialism and relationships with Russia and the Soviet Union are treated in the construction of new urban identities in postsocialist CEE, particularly in the case of LĂłdz, Poland. After outlining the treatment of the socialist past in Polish society and politics, the article analyses the contested construction of a new identity for LĂłdz. The analysis focuses on the construction of a past multicultural `European' `Golden Age' for the city to create a new identity for it, and how that identity is contested and disrupted by the re-emergence of the city's socialist past and the history of its relations with Russia and the Soviet Union.The article concludes by outlining the broader implications of the case-study for the understanding of postsocialist urban identity formation

    Multiwavelength behaviour of the blazar 3C 279: Decade-long study from Îł -ray to radio

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    © 2020 The Author(s). We report the results of decade-long (2008-2018) Îł -ray to 1 GHz radio monitoring of the blazar 3C 279, including GASP/WEBT, Fermi and Swift data, as well as polarimetric and spectroscopic data. The X-ray and Îł -ray light curves correlate well, with no delay ≳ 3 h, implying general cospatiality of the emission regions. The Îł -ray-optical flux-flux relation changes with activity state, ranging from a linear to amore complex dependence. The behaviour of the Stokes parameters at optical and radio wavelengths, including 43 GHz Very Long Baseline Array images, supports either a predominantly helical magnetic field or motion of the radiating plasma along a spiral path. Apparent speeds of emission knots range from 10 to 37c, with the highest values requiring bulk Lorentz factors close to those needed to explain Îł -ray variability on very short time-scales. The MgII emission line flux in the 'blue' and 'red' wings correlates with the optical synchrotron continuum flux density, possibly providing a variable source of seed photons for inverse Compton scattering. In the radio bands, we find progressive delays of the most prominent light-curve maxima with decreasing frequency, as expected from the frequency dependence of the τ= 1 surface of synchrotron self-absorption. The global maximum in the 86 GHz light curve becomes less prominent at lower frequencies, while a local maximum, appearing in 2014, strengthens toward decreasing frequencies, becoming pronounced at ∌5 GHz. These tendencies suggest different Doppler boosting of stratified radio-emitting zones in the jet

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    The Cryptochrome Blue Light Receptors

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