162 research outputs found

    about the early international congresses of applied mechanics

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    Several authors have discussed the conflict, during and after the first world war, between the internationalist ideology of scientific knowledge and the political commitment of scientists, in particular with regard to the policy of the International Research Council and of its scientific unions. A case study is presented here of an international body which was born during the Twenties (when the polemic between scientists on opposite sides was at its peak) and quickly attained unpredicted success. Preceded by an informal gathering organized by T. von Karman and T. Levi-Civita in Innsbruck in 1922, the International Congress of Applied Mechanics, first held in Delft in 1924, was, at the end of the decade, much more of a live institution than many of the unions tied to the IRC

    Masters and students in italian physics between the 19th and the 20th centuries: the Felici-Bartoli-Stracciati-Corbino case

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    In the second half of the 19th century, a special practice of research and training in physics took shape in Pisa, characterized by a particular attention to theoretical studies and to combining experimental activity with a profound mastery of mathematical tools. This peculiar approach, started by Carlo Matteucci and Ottaviano Mossotti, continued and spread by Riccardo Felici, Enrico Betti, Adolfo Bartoli and Vito Volterra, was quite an exception in the framework generally marked by strict experimentalism and positivist empiricism of the Italian physics cabinets of the time. The present paper highlights a special path connecting this tradition of the Pisan school to the scientific environment that was formed in the early years of the 20th century at the Royal Physical Institute in Via Panisperna in Rome, through the interaction of Orso Mario Corbino with Volterra on one side, and the imprinting left on Corbino by Adolfo Bartoli and his student and collaborator Enrico Stracciati

    Harmonization of VFAs measurement by GC: something more than R2 to evaluate the calibration function

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    Anaerobic digestion is sensitive to many environmental factors requiring a robust control of this process. One of the analytical measurements considered as key parameter is the volatile fatty acids (VFAs) content. Total amount of volatile acids (TVFA) to control the relative changes over time has been suggested as a useful tool. However, TVFA does not provide sufficient information to reveal the overall reactor performance, and individual components have been considered of particular interest. Although some attempts have been described as on-line measurements for individual VFAs, normally they are determined by off-line chromatographic techniques (GC and HPLC). A previous interlaboratory study showed the lack of harmonization in the analytical methodologies dealing to individual VFAs, and giving an overall analytical performance rather poor. One of the reasons to justify these results was the inappropriate calibration procedures. It is widely used to check the linearity of the calibration curves based on the correlation and determination coefficients. However, these statistical parameters are erroneously interpreted. The objective of this interlaboratory study was to achieve the harmonization of results. By this way, the use of internal standard methodology (ISTD) should be useful to obtain accurate calibration functions. In addition, five different statistical parameters such as lack of fit test, residual standard deviation, relative standard deviation of the slope, relative standard deviation of the sensitivity and relative error were proposed to evaluate the linearity of calibration curves. Of these, lack of fit was unable to detect appropriately the linearity mainly due to its sensitivity to the precision of analytical results. The rest of statistical parameters reported could be considered as starting point for comparative purposes, being useful as acceptance criteria. The principal advantage of the GC/ISTD analytical methodology was the normalization of the slopes obtained by the participating laboratories, being very helpful to the harmonization of results.Peer Reviewe

    Peripartum cardiomyopathy

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    Peripartum cardiomyopathy is an uncommon form of congestive heart failure associated with systolic dysfunction of left ventricle. The onset is characterised by symptoms of heart failure occurring between the last month of pregnancy and 5-6 months postpartum. The early diagnosis and the institution of medical treatment for this disease are essential because the inadequate management may affect the patient’s long-term prognosis and can lead to severe complications, including death.Currently its aetiology is not completely understood. Many aetiopathogenetic hypotheses have been formulated: inflammation, viral agents, autoimmune processes. In the last years, evidences aroused for a role of prolactin and its 16 kDa metabolite in reducing cardiomyocite metabolic activity and contraction. In this article we have reviewed the current literature with special emphasis on the role of prolactin and the related current treatment strategies. In particular, bromocriptine appears promising, even if women need to be informed that the drug stops the production of breastmilk. Further researchers, such as large multicenter trials, are needed to decide the best treatment for the women suffering of this disease

    Dissipation Function: Nonequilibrium Physics and Dynamical Systems

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    An exact response theory has recently been developed within the field of Nonequilibrium Molecular Dynamics. Its main ingredient is known as the Dissipation Function, Ω. This quantity determines nonequilbrium properties like thermodynamic potentials do with equilibrium states. In particular, Ω can be used to determine the exact response of particle systems obeying classical mechanical laws, subjected to perturbations of arbitrary size. Under certain conditions, it can also be used to express the response of a single system, in contrast to the standard response theory, which concerns ensembles of identical systems. The dimensions of Ω are those of a rate, hence Ω can be associated with the entropy production rate, provided local thermodynamic equilibrium holds. When this is not the case for a particle system, or generic dynamical systems are considered, Ω can equally be defined, and it yields formal, thermodynamic-like, relations. While such relations may have no physical content, they may still constitute interesting characterizations of the relevant dynamics. Moreover, such a formal approach turns physically relevant, because it allows a deeper analysis of Ω and of response theory than possible in case of fully fledged physical models. Here, we investigate the relation between linear and exact response, pointing out conditions for the validity of the response theory, as well as difficulties and opportunities for the physical interpretation of certain formal results

    Bruno Touschek: particle physicist and father of the electron-positron collider

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    This article gives a brief outline of the life and works of the Austrian physicist Bruno Touschek, who conceived, proposed and, 50 years ago, brought to completion the construction of AdA, the first electron-positron storage ring. The events which led to the approval of the AdA pro ject and the Franco-Italian collaboration which con- firmed the feasibility of electron-positron storage rings will be recalled. We shall illustrate Bruno Touschek's formation both as a theoretical physicist and as an expert in particle accelerators during the period be- tween the time he had to leave the Vienna Staat Gymnasium in 1938, because of his Jewish origin from the maternal side, until he arrived in Italy in the early 1950s and, in 1960, proposed to build AdA, in Frascati. The events which led to Touschek's collaboration with Rolf Wideroe in the construction of the first European betatron will be de- scribed. The article will make use of a number of unpublished as well as previously unknown documents, which include an early correspon- dence with Arnold Sommerfeld and Bruno Touschek's letters to his family in Vienna from Italy, Germany and Great Britain. The impact of Touschek's work on students and collaborators from University of Rome will be illustrated through his work on QED infrared radiative corrections to high energy e+e- experiments and the book Meccanica Statistica.Comment: To be published in EPJ

    A reciprocal legitimation: Corrado Gini and statistics in fascist Italy

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    This article deals with the relationship between science and politics and in particular with the reciprocal legitimation process involving research schools and political regimes. It focuses on the case of Italian statistics during the early twentieth century. Its emergence as both an independent scientific field and a national research school, in fact, went together with the rise of nationalism and the establishment of the fascist regime. The paper uses the biography of Corrado Gini to analyze the process of mutual legitimization between science and politics under fascism. Gini's academic and professional careers show in fact how actors and ideas could compete through their ability to alter the status of the discipline, the technical functions it was assigned, and to attract funds in a changing political context Gini, as an institutional entrepreneur, was able to make his research school hegemonic in Italy by leveraging the need for scientific legitimation of new state policies during World War I and under fascism. The reinterpretation he provided of his career after the end of World War II is crucial both to deconstructing this process and to shedding light on the postwar de-legitimation of Italian statistics
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