Time-dependent energy absorption changes during ultrafast lattice deformation

The ultrafast time-dependence of the energy absorption of covalent solids upon excitation with femtosecond laser pulses is theoretically analyzed. We use a microscopic theory to describe laser induced structural changes and their influence on the electronic properties. We show that from the time evolution of the energy absorbed by the system important information on the electronic and atomic structure during ultrafast phase transitions can be gained. Our results reflect how structural changes affect the capability of the system to absorb external energy.Comment: 7 pages RevTeX, 8 ps figures, submitted to Journal of Appl. Physic

Effect of gene-gene and gene-environment interactions associated with antituberculosis drug-induced hepatotoxicity

This study evaluated the association between environmental factors and genetic variations in enzymes that metabolize antituberculosis (anti-TB) drugs [arylamine N-acetyltransferase 2, cytochrome P450 2E1 (CYP2E1), glutathione S-transferase theta 1 (GSTT1), and glutathione S-transferase mu 1] with antituberculosis drug-induced hepatotoxicity (ATDH). We also investigated the potential gene-gene and gene-environment interactions as well as their association with ATDH development in a population of hospitalized TB patients from Buenos Aires

First spectroscopic investigation of Anomalous Cepheid variables

Anomalous Cepheids (ACEPs) are intermediate mass metal-poor pulsators mostly discovered in dwarf galaxies of the Local Group. However, recent Galactic surveys, including the Gaia DR3, found a few hundreds of ACEPs in the Milky Way. Their origin is not well understood. We aim to investigate the origin and evolution of Galactic ACEPs by studying for the first time the chemical composition of their atmospheres. We used UVES@VLT to obtain high-resolution spectra for a sample of 9 ACEPs belonging to the Galactic halo. We derived the abundances of 12 elements, including C, Na, Mg, Si, Ca, Sc, Ti, Cr, Fe, Ni, Y, and Ba. We complemented these data with literature abundances for an additional three ACEPs that were previously incorrectly classified as type II Cepheids, thus increasing the sample to a total of 12 stars. All the investigated ACEPs have an iron abundance [Fe/H]$<-1.5$ dex as expected from theoretical predictions for these pulsators. The abundance ratios of the different elements to iron show that the ACEP's chemical composition is generally consistent with that of the Galactic halo field stars, except the Sodium, which is found overabundant in 9 out of the 11 ACEPs where it was measured, in close similarity with second-generation stars in the Galactic Globular Clusters. The same comparison with dwarf and ultra-faint satellites of the Milky Way reveals more differences than similarities so it is unlikely that the bulk of Galactic ACEPs originated in such a kind of galaxies which subsequently dissolved in the Galactic halo. The principal finding of this work is the unexpected overabundance of Sodium in ACEPs. We explored several hypotheses to explain this feature, finding that the most promising scenario is the evolution of low-mass stars in a binary system with either mass transfer or merging. Detailed modelling is needed to confirm this hypothesis.Comment: 15 Figures, 4 Tables, Accepted for publication on Astronomy & Astrophysic

Elites, democracy, and parties in the Italian Constituent debates, 1946–1947

Discussions of the role and legitimacy of elites in democratic societies have rarely taken the shape of debates about the internal organization and working of political parties. Except for Michels and Ostrogorski, the party has not received much attention from theorists interested in the elitist dimensions of democratic politics. In this article, I purport to look at the party as a battling ground for competing accounts of the role elites should play in modern democratic societies. However, I will not focus on theoretical analyses of the party. Rather, I will look at how political actors discussed the party in the context of the constituent debates at the Italian Constituent Assembly of 1946–1947. These debates do not explicitly deal with the role elites should play in democratic society. Instead, they center on whether and how the constitution should regulate political parties. Yet while discussing details of legal regulation, the constituents offered contrasting understandings of modern democracy, competing accounts of the role of the masses as well as of the elites, and creative attempts to create stable compromises between the two in a changing society. It is through the reconstruction of these rather practical debates that I aim to uncover how one of the main questions of modern democracy—the relation between elites and masses—has been dealt with politically. This, I suggest, is not only interesting for political or historiographical reasons, but also has theoretical relevance. Not only it directly speaks to recent debates about partisanship and intraparty deliberation, but it is also by looking at political institutions and the reasoning behind their creation that one can recover complex political thinking.1 This, I believe, is made particularly interesting by the fact that it results from long and complicated processes of negotiation of contrasting values as well as from the translation of political ideals into working institutional structures. Reconstructing these processes of negotiation and translation is what I plan to do in this article

The impact of community-based arts and health interventions on cognition in people with dementia: a systematic literature review

Objectives: Dementia is a progressive condition, affecting increasing numbers of people, characterised by cognitive decline. The current systematic review aimed to evaluate research pertaining to the impact of arts and health interventions on cognition in people with dementia. Method: A literature search was conducted utilising PsychInfo, Cochrane Reviews, Web of Science, Medline and British Humanities Index databases. Seventeen studies were included in the review, including those related to literary, performing and visual arts. Results: The review highlighted this as an emerging area of research with the literature consisting largely of small-scale studies with methodological limitations including lack of control groups and often poorly defined samples. All the studies suggested, however, that arts-based activities had a positive impact on cognitive processes, in particular on attention, stimulation of memories, enhanced communication and engagement with creative activities. Conclusion: The existent literature suggests that arts activities are helpful interventions within dementia care. A consensus has yet to emerge, however, about the direction for future research including the challenge of measurement and the importance of methodological flexibility. It is suggested that further research address some of these limitations by examining whether the impact of interventions vary depending n cognitive ability and to continue to assess how arts interventions can be of use across the stages of dementia

Radiation hardness qualification of PbWO4 scintillation crystals for the CMS Electromagnetic Calorimeter

This is the Pre-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2010 IOPEnsuring the radiation hardness of PbWO4 crystals was one of the main priorities during the construction of the electromagnetic calorimeter of the CMS experiment at CERN. The production on an industrial scale of radiation hard crystals and their certification over a period of several years represented a difficult challenge both for CMS and for the crystal suppliers. The present article reviews the related scientific and technological problems encountered

Intercalibration of the barrel electromagnetic calorimeter of the CMS experiment at start-up

Calibration of the relative response of the individual channels of the barrel electromagnetic calorimeter of the CMS detector was accomplished, before installation, with cosmic ray muons and test beams. One fourth of the calorimeter was exposed to a beam of high energy electrons and the relative calibration of the channels, the intercalibration, was found to be reproducible to a precision of about 0.3%. Additionally, data were collected with cosmic rays for the entire ECAL barrel during the commissioning phase. By comparing the intercalibration constants obtained with the electron beam data with those from the cosmic ray data, it is demonstrated that the latter provide an intercalibration precision of 1.5% over most of the barrel ECAL. The best intercalibration precision is expected to come from the analysis of events collected in situ during the LHC operation. Using data collected with both electrons and pion beams, several aspects of the intercalibration procedures based on electrons or neutral pions were investigated

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum