2,334 research outputs found

    Astronomia e Fisica a Firenze : dalla Specola ad Arcetri

    Get PDF
    La Mostra Astronomia e Fisica a Firenze illustra l’evoluzione delle due discipline dal XVIII secolo fino ai primi decenni del Novecento. Teatro cittadino di questo processo, anzi di tutte le scienze, fu l’Imperiale e Reale Museo di Fisica e Storia Naturale, dove adesso ha sede la Mostra. Nell’arco di tempo esaminato tutti gli aspetti dell’indagine della natura erano ugualmente pertinenti ad un’unica figura di studioso, ma verso l’inizio del XX secolo alcuni indirizzi subirono una profonda trasformazione e al prevalente approccio tassonomico e fenomenologico subentrò, soprattutto per Astronomia e Fisica, un’indagine specialistica che finì per differenziare le varie ricerche. Protagonista di questa fase fu lo sviluppo dell’analisi spettroscopica. La Mostra, aperta da dicembre 2016 a marzo 2017, è organizzata dall’Università di Firenze (Museo di Storia Naturale; Dipartimento di Fisica e Astronomia) e dall’Osservatorio Astrofisico di Arcetri, in collaborazione con la Sezione di Firenze dell’INFN, il Museo Galileo, l’Archivio Storico del Comune di Firenze, l’Istituto Nazionale di Ottica del CNR e la Biblioteca di Scienze dell’Universit

    Italy’s Path to Very Low Fertility: The Adequacy of Economic and Second Demographic Transition Theories: Le cheminement de l’Italie vers les très basses fécondités: Adéquation des théories économique et de seconde transition démographique

    Get PDF
    The deep drop of the fertility rate in Italy to among the lowest in the world challenges contemporary theories of childbearing and family building. Among high-income countries, Italy was presumed to have characteristics of family values and female labor force participation that would favor higher fertility than its European neighbors to the north. We test competing economic and cultural explanations, drawing on new nationally representative, longitudinal data to examine first union, first birth, and second birth. Our event history analysis finds some support for economic determinants of family formation and fertility, but the clear importance of regional differences and of secularization suggests that such an explanation is at best incomplete and that cultural and ideational factors must be considered

    HIV incidence estimate combining HIV/AIDS surveillance, testing history information and HIV test to identify recent infections in Lazio, Italy

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The application of serological methods in HIV/AIDS routine surveillance systems to identify persons with recently acquired HIV infection has been proposed as a tool which may provide an accurate description of the current transmission patterns of HIV. Using the information about recent infection it is possible to estimate HIV incidence, according to the model proposed by Karon et al. in 2008, that accounts for the effect of testing practices on the number of persons detected as recently infected.</p> <p>Methods</p> <p>We used data from HIV/AIDS surveillance in the period 2004-2008 to identify newly diagnosed persons. These were classified with recent/non-recent infection on the basis of an avidity index result, or laboratory evidence of recently acquired infection (i.e., previous documented negative HIV test within 6 months; or presence of HIV RNA or p24 antigen with simultaneous negative/indeterminate HIV antibody test). Multiple imputation was used to impute missing information. The incidence estimate was obtained as the number of persons detected as recently infected divided by the estimated probability of detection. Estimates were stratified by calendar year, transmission category, gender and nationality.</p> <p>Results</p> <p>During the period considered 3,633 new HIV diagnoses were reported to the regional surveillance system. Applying the model, we estimated that in 2004-2008 there were 5,465 new infections (95%CI: 4,538-6,461); stratifying by transmission category, the estimated number of infections was 2,599 among heterosexual contacts, 2,208 among men-who-have-sex-with-men, and 763 among injecting-drug-users. In 2008 there were 952 (625-1,229) new HIV infections (incidence of 19.9 per 100,000 person-years). In 2008, for men-who-have-sex-with-men (691 per 100,000 person-years) and injecting drug users (577 per 100,000 person-years) the incidence remained comparatively high with respect to the general population, although a decreasing pattern during 2004-2008 was observed for injecting-drug-users.</p> <p>Conclusions</p> <p>These estimates suggest that the transmission of HIV infection in Lazio remains frequent and men-who-have-sex-with men and injecting-drug-users are still greatly affected although the majority of new infections occurs among heterosexual individuals.</p

    Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

    Get PDF
    Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio

    Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan