220 research outputs found

    On the relation of Voevodsky's algebraic cobordism to Quillen's K-theory

    Full text link
    Quillen's algebraic K-theory is reconstructed via Voevodsky's algebraic cobordism. More precisely, for a ground field k the algebraic cobordism P^1-spectrum MGL of Voevodsky is considered as a commutative P^1-ring spectrum. There is a unique ring morphism MGL^{2*,*}(k)--> Z which sends the class [X]_{MGL} of a smooth projective k-variety X to the Euler characteristic of the structure sheaf of X. Our main result states that there is a canonical grade preserving isomorphism of ring cohomology theories MGL^{*,*}(X,U) \tensor_{MGL^{2*,*}(k)} Z --> K^{TT}_{- *}(X,U) = K'_{- *}(X-U)} on the category of smooth k-varieties, where K^{TT}_* is Thomason-Trobaugh K-theory and K'_* is Quillen's K'-theory. In particular, the left hand side is a ring cohomology theory. Moreover both theories are oriented and the isomorphism above respects the orientations. The result is an algebraic version of a theorem due to Conner and Floyd. That theorem reconstructs complex K-theory via complex cobordism.Comment: LaTeX, 18 pages, uses XY-pi

    Estimation of tail probabilities in detection

    Get PDF
    Two approximate analytical methods allowing a quick evaluation of the false alarm probability in detection are presented . Th e first one is based on the Chernov bound, properly modified to give an equivalent of the false alarm probability when the threshol d tends to infinity. It can be applied whenever the moment generating function is available, for instance in the case of the quadrati c detector. The second one is based on the classical formula for the volume of a tube about a manifold on the unit sphere of Rn . I t can be applied to all detectors which maximize the squared norm of a projection in a family of subspaces . As a function of th e threshold, the result can be expressed in both cases as the product of a constant, a power, and an exponential .On présente deux méthodes analytiques approchées permettant l'évaluation rapide d'une probabilité de fausse alarme en détection. La première repose sur la borne de Chernov, complétée par un facteur correctif pour transformer cette borne en un équivalent de la probabilité de fausse alarme lorsque le seuil tend vers l'infini. Elle s'applique chaque fois que la fonction génératrice des moments est disponible, notamment dans le cas du détecteur quadratique. La seconde repose sur l'expression classique donnant le volume du tube associé à une variété portée par la sphère unité dans Rn. Elle s'applique aux détecteurs maximisant la norme au carré d'une projection dans une famille de sous espaces. Dans les deux cas, le résultat obtenu s'exprime en fonction du seuil par le produit d'une constante, d'une puissance et d'une exponentielle

    Knowledge, attitudes, and practices of influenza and pneumococcal vaccines among agricultural workers: Results of an Italian a cross-sectional study

    Get PDF
    Background: Working age is increasing across Europe. Seasonal influenza (SID) and pneumococcal disease (PND) immunization programmes might be successfully implemented at the workplace. We conducted a cross-sectional survey among to assess SID and PND vaccine status, as well as knowledge, attitudes and practices (KAP) in a representative sample of agricultural workers (AWs) aged ≥55 years in North-Eastern Italy. Methods: A structured questionnaire was administered in person by trained personnel. Bivariate and multivariate logistic regression analyses were carried out to identify behavioral and work-related factors associated with SID and PND vaccine uptake. Results: Among 707 participants, 238 were aged 55 years or more (33.7% of total). Of them, 39.1% had an up-to-date immunization status towards influenza, and 17.6% towards pneumococcus. Factors associated with inadequate immunization were doubts about influenza vaccine safety (40.0%) and the confidence in natural immunity towards pneumococcus (30.8%). Attitude towards vaccinations was somehow favorable in 44.5% of participants for SID, and 37.8% for PND. Overall, 37.4% and 21.8% workers were aware of national recommendations on SID and PND immunization, respectively. This factor was characterized as a significant predictor for SID vaccination (multivariated Odds Ratio, OR 32.688 95%CI 12.015-88.930), as well as the perception of SID as a severe disease (OR 7.539 95%CI 3.312-17.164), and the perceived value of preventing new infections (OR 3.215 95%CI 1.205-8.578). A somehow favorable attitude towards vaccinations was the main predictor (OR 39.214 95%CI 10.179-151.1) for PND vaccination. Conclusions: Our study indicates that older workers lack appropriate knowledge of national recommendations and correct risk perception of SID and PND infections, but also vaccines’ side effects. As the latter has been recognized as predictive factor for SID vaccination, our results stress the importance for tailored informative interventions in the workplaces aimed to increase risk perception and vaccine acceptance. (www.actabiomedica.it)

    Epidemiology of leprosy in Italy (1920-2019): A comprehensive review on existing data

    Get PDF
    Background and aims: Incidence of leprosy in Italy has declined steadily over the last century, but available evidence remains fragmentary. Our review aims to summarize available data on the epidemiology of leprosy cases in Italy. Methods: The following keywords were used to explore PubMed and Embase: leprosy, Hansen’s disease, (Mycobacterium) leprae, Italy, without any chronological restriction. Results: We identified a total of 39 reports, including 7 national reports, 11 international reports, 20 case reports. Notified leprosy cases were: 839 between 1925 and 1948; 434 between 1955 and 1979; 76 cases for the decade 1980-1989; 112 between 1990 and 1999; 62 between 2000 and 2009, and a total of 25 cases since 2009. Since 2003, 53% of all cases occurred in illegal residents. Focusing on individual cases, latency between early signs/symptoms and a proper diagnosis ranged between 2 and 20 years in 52.1% of individual cases. Conclusion: Imported cases of leprosy are responsible for most leprosy incidence in Italy, and social stigma, the unfamiliarity of healthcare professionals with such disorders, and difficulties of some high-risk groups to be appropriately assessed hint to a possible under-diagnosis. Professionals should be made more aware of the potential for leprosy incidence among patients from countries where the disease is endemic. (www.actabiomedica.it)

    The sources of committee Influence in the European Parliament

    Get PDF
    The European Parliament (EP) has evolved into a powerful legislative actor over the past 40 years. In order to exercise its hard won legislative competencies in an efficient and effective manner the EP has developed an extensive and influential committee system. The Treaty of Lisbon (ToL) recognised its equal status as co-legislator with the Council of the EU and introduced the Ordinary Legislative Procedure (OLP) as the default EU legislative procedure. Despite the fact that after the introduction of the OLP all EP committees formally operate under the same legal procedure, disparities remain in the levels of influence that each committee commands. This state of affairs demonstrates that if we are to understand what drives committee influence we need to explore the informal sources of influence that committees draw on in addition to the formal rules. This project addresses the lack of understanding of how the committees establish legislative influence by identifying and testing the different resources which committees may be utilising to establish their influence. The thesis puts forward four hypotheses concerning the factors that can account for how committees establish influence. These are developed and tested within three case studies. The case studies comprise the highly influential committees on, firstly, the Environment, Public Health and Food Safety Committee, secondly, the Budget Committee and, thirdly, the International Trade Committee. The research project adopts a qualitative approach to complement and create a different perspective from the quantitative studies which dominate the field. It draws on extensive primary material from thirty semi-structured interviews held with MEPs, advisers, EP staff and party officials active in the 7th legislative term (2009-2014). A number of the current conventions concerning the way in which expertise, partisan dynamics, and policy outputs affect how committees establish legislative influence are challenged and new insights regarding their relative importance are offered. Overall, these original findings, contained within this dissertation, have highly significant implications, not only with regard to the committee system of the EP but, also, for the wider field of legislative politics
    • …
    corecore