14 research outputs found

    The Late Civil War

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    The Narrowest M-dwarf Line Profiles and the Rotation-Activity Connection at Very Slow Rotation

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    The rotation-activity connection explains stellar activity in terms of rotation and convective overturn time. It is well established in stars of spectral types F--K and in M-type stars of young clusters. It is not established in field M-dwarfs, because they rotate very slowly, and detecting rotation periods or rotational line broadening is a challenge. In field M-dwarfs, saturation sets in below v_rot = 5 km/s, hence they are expected to populate the non-saturated part of the rotation-activity connection. This work for the first time shows intrinsically resolved spectral lines of slowly rotating M-dwarfs and makes a first comparison to estimates of convective velocities. By measuring rotation velocities in a sample of mostly inactive M-dwarfs, the unsaturated part of the rotation-activity connection is followed into the regime of very low activity. Spectra of ten M-dwarfs are taken at a resolving power of R = 200 000 in the molecular FeH absorption band. The intrinsically narrow lines are compared to model calculations and rotational broadening is measured. In one star, an upper limit of vsini = 1 km/s was found, significant rotation was detected in the other nine objects. All inactive stars show rotation below or equal to 2 km/s. In the two active stars AD Leo and YZ CMi, rotation velocities are found to be 40-50% below the results from earlier studies. The rotation activity connection holds in field early-M stars, too. Activity and rotation velocities of the sample stars are well in agreement with the relation found in earlier and younger stars. The intrinsic absorption profiles of molecular FeH lines are consistent with calculations from atomic Fe lines. Investigation of FeH line profiles is a very promising tool to measure convection patterns at the surfaces of M-stars.Comment: accepted by A&A, 11 pages [abstract abridged

    The Late Civil War

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    PORPHYRIA CUTANEA TARDA AND HEPATITIS C AND G VIRUSES INFECTIONS :STUDY IN A CENTER-SOUTH

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    Decentralization in Italy and the troubles of federalization

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    Since the mid-1990s, Italy has made significant steps towards federalism, decentralizing political, fiscal and administrative powers, also by means of a major constitutional reform. Yet, 20 years after the beginning of this process, the country is experiencing problems in finalizing these reforms towards a stable federal architecture. This article examines Italy as a case of failed federalization. Adopting a long-term focus inspired by the \u2018gradual institutional change\u2019 approach, we argue that federalization has been trapped between a rather anomalous (and pathological) alliance between a persistent centralism, which prevailed when Italy was born as a state in 1861, and an ever-present strong tradition of localism. This approach allows us to show the very incremental nature of institutional change and to map changes and continuities along the 150 years of the Italian state, identifying both political and cultural factors that help to explain this unfulfilled journey towards federalism
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