92 research outputs found

    "Pre-Earthquake" Micro-Structural Effects Induced by Shear Stress on α-Quartz in Laboratory Experiments

    Get PDF
    This paper presents the results of measurements performed on α-quartz subjected to shear stress in dry conditions, to understand the relationship between the shear intensity and the resulting physical and chemical effects. If a shear stress of intensity higher than 100 MPa is applied continuously to alpha quartz crystals, they will tend to lose their crystallinity, progressively reduce their friction coefficient (Cof) and change into a low-order material, apparently amorphous under X-ray diffraction, but with a structure different from silica glass. Raman and Pair Distribution Function analyses suggested a structure like cristobalite, a silica polymorph well-known for its auxetic behavior, i.e., having a negative Poisson ratio. This elastic parameter pre-eminently controls the friction coefficient of the material and, if it is negative, the Cof lowering. As a result, the increase in low crystallinity cristobalite is sufficientto explain the lowering of the quartz friction coefficient up to values able to contribute, in principle, to the triggering processes of active faults. This allows hypothesizing a slip induction mechanism that does not include the need to have the interposition of layers of hydrated silica, as invoked by many authors, to justify the low friction coefficients that are achieved in shear stress tests on rocks abundant in quartz

    The Community Assessment Psychic Experience (CAPE): evaluation study of the Italian version

    Get PDF
    AbstractNegli ultimi anni il modello categoriale della psicosi e della schizofrenia in particolare, è stato riconsiderato a favore di una visione dimensionale. Questa assume che I sintomi psicotici differiscono in modo quantitativo dalle normali esperienze psichiche distribuendosi lungo un continuum che va dalla popolazione clinica affetta da schizofrenia ad individui con disturbo di personalità, fino alla popolazione generale che può mostrare esperienze simil psicotiche (Hanssen et al., 2003; Johns & Phil, 2005). Tale continuità fenomenologica è suggerita da studi che mostrano che le dimensioni del fenotipo della psicosi subclinica sono molto simili a quelle identificate nei disturbi clinici (Van Os et al. 2000; Van Os & Tamminga, 2007; Rossler et al., 2007). Sono state infatti riportate dimensioni positive e negative sia in ambito clinico che subclinico, mentre più incerta appare la presenza della dimensione disorganizzazione (Vollema & Hoijtink, 2000; van Os et al., 2002). Vari studi hanno riportato che i fenotipi clinico e non clinico condividono fattori di rischio, meccanismi psicologici ed i pattern epidemiologici (Sharpley & Peters,1999; Johns & van Os, 2001; van Os et al., 2001), fornendo un'ulteriore prova che l'espressione clinica e subclinica delle psicosi fanno parte dello stesso continuum

    Feline Coronavirus and Alpha-Herpesvirus Infections: Innate Immune Response and Immune Escape Mechanisms

    Get PDF
    Over time, feline viruses have acquired elaborateopportunistic properties, making their infections particularly difficult to prevent and treat. Feline coronavirus (FCoV) and feline herpesvirus-1 (FeHV-1), due to the involvement of host genetic factors and immune mechanisms in the development of the disease and more severe forms, are important examples of immune evasion of the host’s innate immune response by feline viruses.It is widely accepted that the innate immune system, which providesan initial universal form of the mammalian host protection from infectious diseases without pre-exposure, plays an essential role in determining the outcome of viral infection.The main components of this immune systembranchare represented by the internal sensors of the host cells that are able to perceive the presence of viral component, including nucleic acids, to start and trigger the production of first type interferon and to activate the cytotoxicity by Natural Killercells, often exploited by viruses for immune evasion.In this brief review, we providea general overview of the principal tools of innate immunity, focusing on the immunologic escape implemented by FCoVand FeHV-1 during infection

    Osservatorio sulle edizioni critiche

    Get PDF
    Ospitiamo qui il progetto dell’ “Osservatorio sulle edizioni critiche” proposto da un gruppo di ricerca del Dipartimento di Studi letterari, filologici e linguistici dell'Università degli Studi di Milano, composto da Alberto Cadioli, Paolo Chiesa, Stefano Martinelli Tempesta, William Spaggiari, Roberto Tagliani. Ora il gruppo di lavoro intorno al progetto, coinvolge anche Paolo Borsa, Virna Brigatti, Massimiliano Gaggero, Rossana Guglielmetti, Giulia Ravera. Il progetto è stato presentato in un seminario tenutosi a Milano il 13 settembre 2017 (si veda la Cronaca accolta in questo terzo numero di «Prassi Ecdotiche della Modernità Letteraria: https://riviste.unimi.it/index.php/PEML/article/view/9272).   Observatory on Critical Editions The project “An Observatory on critical editions” is promoted by the Department of Literature, Philolgy and Linguistics of Università degli Studi di Milano. The research group is formed by Alberto Cadioli, Paolo Chiesa, Stefano Martinelli Tempesta, William Spaggiari, Roberto Tagliani. By now, the research team also involves Paolo Borsa, Virna Brigatti, Massimiliano Gaggero, Rossana Guglielmetti, Giulia Ravera. Tha project was presented during the seminar held in Milan on September the 13th 2017 (please see the resume published in this issue of «Prassi Ecdotiche della Modernità Letteraria»: https://riviste.unimi.it/index.php/PEML/article/view/9272)

    Fe-rich ferropericlase and magnesiow\ufcstite inclusions reflecting diamond formation rather than ambient mantle

    Get PDF
    At the core of many Earth-scale processes is the question of what the deep mantle is made of. The only direct samples from such extreme depths are diamonds and their inclusions. It is commonly assumed that these inclusions reflect ambient mantle or are syngenetic with diamond, but these assumptions are rarely tested. We have studied inclusion\u2013host growth relationships in two potentially superdeep diamonds from Juina (Brazil) containing nine inclusions of Fe-rich (XFe 480.33 to 650.64) ferropericlase-magnesiow\ufcstite (FM) by X-ray diffractometry, X-ray tomography, cathodoluminescence, electron backscatter diffraction, and electron microprobe analysis. The inclusions share a common [112] zone axis with their diamonds and have their major crystallographic axes within 3\ub0\u20138\ub0 of those of their hosts. This suggests a specific crystallographic orientation relationship (COR) resulting from interfacial energy minimization, disturbed by minor post-entrapment rotation around [112] due to plastic deformation. The observed COR and the relationships between inclusions and diamond growth zones imply that FM nucleated during the growth history of the diamond. Therefore, these inclusions may not provide direct information on the ambient mantle prior to diamond formation. Consequently, a \u201cnon-pyrolitic\u201d composition of the lower mantle is not required to explain the occurrence of Fe-rich FM inclusions in diamonds. By identifying examples of mineral inclusions that reflect the local environment of diamond formation and not ambient mantle, we provide both a cautionary tale and a means to test diamond-inclusion time relationships for proper application of inclusion studies to whole-mantle questions

    Bonding of the Inner Tracker Silicon Microstrip Modules

    Get PDF
    Microbonding of the CMS Tracker Inner Barrel (TIB) and Tracker Inner Disks (TID) modules was shared among six different Italian Institutes. The organization devised and the infrastructure deployed to handle this task is illustrated. Microbonding specifications and procedures for the different types of TIB and TID modules are given. The tooling specially designed and developed for these types of modules is described. Experience of production is presented. Attained production rates are given. An analysis of the microbonding quality achieved is presented, based on bond strengths measured in sample bond pull tests as well as on rates of bonding failures. Italian Bonding Centers routinely performed well above minimum specifications and a very low global introduced failure rate, at the strip level, of only \sim0.015 \% is observed

    Study of radiation damage and substrate resistivity effects from beam test of silicon microstrip detectors using LHC readout electronics

    Get PDF
    We present the beam test results of single-sided silicon microstrip detectors, with different substrate resistivities. The effects of radiation damage are studied for a detector irradiated to a fluence of 2.4 multiplied by 10**1**4 n/cm**2. The detectors are read out with the APV6 chip, which is compatible with the 40 MHz LHC clock. The performance of different detectors and readout modes are studied in terms of signal-to-noise ratio and efficiency

    Assembly of the Inner Tracker Silicon Microstrip Modules

    Get PDF
    This note describes the organization of the mechanical assembly of the nearly 4000 silicon microstrip modules that were constructed in Italy for the Inner Tracker of the CMS experiment. The customization and the calibration of the robotic system adopted by the CMS Tracker community, starting from a general pilot project realized at CERN, is described. The step-by-step assembly procedure is illustrated in detail. Finally, the results for the mechanical precision of all assembled modules are reported

    'Organization Science': A new prospective to assess marine protected areas effectiveness

    Get PDF
    Marine Protected Areas (MPAs) are widely considered as useful tools to achieve both conservation and resource management goals. They have the potential to produce a wide array of positive socio-ecological effects. Their effectiveness, however, varies dramatically. The sources of this variability are numerous and, in some cases, quite well studied. Yet, a significant portion of the variability in MPAs effectiveness still remains unexplained. MPAs, due to a number of intrinsic features, can be considered "organizational systems", a definition recognizing the fact that 1) their effectiveness can be influenced by their own organizational dimensions and 2) they could be analyzed employing the typical tools provided by 'Organization Science' (hereafter OS). Here we analyze the available literature on MPAs on a worldwide scale to explore whether and how the principles of OS have been used as a scientific basis for the evaluation of MPA effectiveness. We found that no study explicitly used a comprehensive OS framework for evaluating effectiveness in the context of MPAs. Just 20 studies considered some organizational dimensions in their analysis (e.g. professionalism of the organization members, vision, goals, strategy and networking), but not in a comprehensive manner. The outputs of our review stress the limited use of the OS methodologies and principles in the context of MPAs so far. We posit that there is a significant potential for new insights in MPA science thanks to a more integrated implementation of an OS framework for the interpretation and improvement of MPA socio-ecological effectiveness

    Epistolari dal Due al Seicento. Modelli, questioni ecdotiche, edizioni, cantieri aperti (Gargnano del Garda, 29 settembre - 1° ottobre 2014)

    Get PDF
    Nei secoli passati, la lettera era l'unico mezzo di comunicazione: familiare, amichevole, d'ufficio o di servizio, ma anche strumento di dibattito politico e culturale. Lo studio degli epistolari dei singoli ma anche delle reti di comunicazione e di scambio è uno dei grandi temi della ricerca europea contemporanea. Vi si inserisce questo secondo volume dei "Quaderni di Gargnano", che - volgendosi sia alla produzione latina sia a quella volgare dal Due al Seicento - si sofferma su problemi metodologici e casi significativi, con impostazioni e tagli diversi: dall'ecdotica alla filologia, dall'archivistica, alla storia, alla storia delle discipline
    corecore