2,050 research outputs found

    Second resonance of the Higgs field: more signals from the LHC experiments

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    It has been proposed that, beside the known resonance with mass mh=m_h= 125 GeV, the Higgs field might exhibit a second resonance with a larger mass (MH)Theor=690±10 (stat)±20 (sys)(M_H)^{\rm Theor} = 690 \pm 10 ~({\rm stat}) \pm 20 ~({\rm sys}) GeV which, however, would couple to longitudinal W's with the same typical strength as the low-mass state at 125125 GeV and thus represent a relatively narrow resonance. Looking for evidences in the LHC data, from two analyses published in 2021 by ATLAS (searching for heavy resonances decaying into final states with 4 charged leptons or with photon pairs) we have found combined indications for a new resonance of mass (MH)Exp∼(M_H)^{\rm Exp} \sim 680 (15) GeV and total width (ΓH)Exp∼(\Gamma_H)^{\rm Exp} \sim 45 (15) GeV. More recent results by CMS (searching for heavy resonances decaying into a pair of h(125) Higgs bosons or looking for high-mass photon pairs produced in pp-diffractive scattering) also show definite excesses pointing toward a new resonance of mass (MH)Exp∼(M_H)^{\rm Exp} \sim 660(30) GeV. However, beside the agreement with the predicted mass range, a clean indication derives from the ATLAS 4-lepton data which reproduce to high accuracy the expected correlation between resonating peak cross section σR(pp→H→4l)\sigma_R(pp\to H \to 4l) and the ratio γH=ΓH/MH\gamma_H=\Gamma_H/M_H. This correlation is mainly determined by the lower mass mh=m_h= 125 GeV and supports the view that the known mhm_h and the new heavy resonance are two different excitations of the same Higgs field by effectively eliminating the spin-zero vs. spin-2 ambiguity in the interpretation of the heavy state. The overall statistical evidence might now be above the traditional 5-sigma discovery threshold because, when comparing with a definite theoretical prediction as in our case, local excesses should maintain intact their statistical significance and not be downgraded by the so called "look-elsewhere" effect.Comment: 14 pages, 4 figures, 4 table

    The Corrosion Behaviour of Additively Manufactured AlSi10Mg Parts Compared to Traditional Al Alloys

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    Additive manufacturing of metal parts in the motorsport industry is becoming a decisive technology for producing lightweight and rigid parts, with increasing applications as the costs decrease. Among the available metal alloys, AlSi10Mg is one of the most widely used. In this paper, the corrosion resistance of additively manufactured AlSi10Mg is compared with that of other traditionally manufactured aluminium alloys widespread in the automotive industry. Several potentially corrosive agents, typical of vehicle applications, were used: salty water, motor oil, suspension oil, cooling fluid and gasoline. Corrosion tests were conducted at both room temperature and 90 C. The effects of heat and surface treatments were evaluated separately. The samples were visually inspected and weighed to evaluate the corrosion rate with the aid of SEM and EDS analysis. Additively manufactured AlSi10Mg generally showed better corrosion resistance in the stress-relieved condition as compared to the T6-treated state, with slightly better results for the polished samples. Motor oil, suspension oil, cooling fluid and gasoline did not significantly corrode the specimens, except for the T6-treated AlSi10Mg samples at 90 C. However, the corrosion rate was always higher than traditionally manufactured aluminium alloys tested for comparison

    La società civile resiliente. Prendersi cura della comunità: indagine sui volontari ANPAS durante la pandemia

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    L’emergenza pandemica da Covid-19 si è rivelata essere un vero e proprio “disastro” dal punto di vista economico e sociale, in quanto ha scosso alle fondamenta i sistemi politici occidentali mettendone in luce le debolezze e le fragilità di fronte alle sfide di un mondo globalizzato. In Italia questa catastrofe ha travolto l’intero sistema di welfare e ha messo a dura prova i principali attori che lo costituiscono, in particolare nel comparto sanitario. In questo ambito, accanto alle istituzioni pubbliche, il Terzo Settore ha svolto un ruolo di primaria importanza. Il volume illustra e commenta i principali risultati di un’indagine sull’impatto della pandemia sui volontari attivi nelle Pubbliche Assistenze affiliate alla rete nazionale ANPAS. La ricerca ha avuto come target il personale volontario coinvolto in prima linea (front-line) nel trasporto sanitario di persone affette da Covid-19, colmando un vuoto conoscitivo. Dall’analisi della letteratura scientifica in ambito delle scienze sociali, epidemiologiche e psicologiche, è emerso che gli studi sulle ricadute psico-fisiche e relazionali della pandemia sugli operatori socio-sanitari hanno riguardato in prevalenza personale retribuito operante presso le strutture ospedaliere. L’indagine muove dalla preoccupazione per lo stato di salute psico-fisica degli operatori delle emergenze e del soccorso sanitario, sottoposti nella fase apicale della diffusione pandemica a forti stress emotivi. Il volume si rivolge agli studiosi del Terzo Settore, agli studenti universitari, nonché a coloro che occupano posizioni di responsabilità nell’ambito delle politiche sanitarie e socio-assistenziali

    Ski Boot Soles Based on a Glass Fiber/Rubber Composite with Improved Grip on Icy Surfaces

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    Abstract A study on the effect of glass fibers/rubber composites on the grip on ice has been conducted in order to develop new materials for ski boot soles with increased grip in winter environments. The study has been conducted analyzing the friction of a composite material and of a ski boot sole containing an insert made of the composite material and comparing the results with those obtained using rubber and a thermoplastic elastomer. The analysis of the morphology of the composite surface, by Scanning Electron Microscopy, shows a homogenous distribution of glass fibers of approximately 10 μm of diameter in the rubber matrix. Moreover, the measure of the contact angle shows that the composite material has a higher water repellency compared to the rubber matrix. The measure of the coefficient of friction indicates a significant effect of the glass fibers on the grip on icy surfaces. The increased grip can be ascribed to the stiffness of the glass fibers that are able to have a mechanical grip on the ice surface and to the increased contact angle and water repellency of the composite that decrease the formation of a water layer below the sole

    Diagnosis of Asthma and COPD

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    Publisher Summary The differential diagnosis between asthma and COPD is quite simple when the typical clinical and functional features of either disease are present. The difficulty comes when trying to make a diagnosis of asthma or COPD in a middle-aged or elderly patient, a smoker, who may be atopic or have a history of asthma, who complains of chronic dyspnea but not wheezing, chronic cough, or sputum, and who presents with poorly reversible airflow limitation. It is also difficult to make a diagnosis of asthma or COPD in a middle-aged or elderly patient who has a clear history of atopy and asthma, bronchodilator reversibility, and recurrent wheezing, but who also smokes and has chronic cough and sputum and dyspnea that are not suppressed by inhaled steroids. The diagnosis of asthma or COPD is based on clinical history and lung function tests, particularly peak expiratory flow (PEF) and spirometry, with assessment of spontaneous or postbronchodilator reversibility of airflow limitation. Allergy tests are also usually performed for the diagnosis of asthma, but not of COPD patients, to identify allergens responsible for asthma exacerbations and to consider the opportunity to treat the patient with immunotherapy. While the diagnosis and assessment of severity of asthma and COPD can be fully established on the basis of clinical history and lung function tests, additional tests might be helpful to better characterize individual patients

    Neurological involvement in Ile68Leu (p.Ile88Leu) ATTR amyloidosis: not only a cardiogenic mutation

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    Ile68Leu transthyretin-related amyloidosis (ATTR) is known as a mainly or exclusively cardiogenic variant. We hypothesized that an accurate specialized neurological evaluation could reveal a consistent frequency of mixed phenotypes.Forty-six consecutive subjects with transthyretin (TTR) Ile68Leu (p.Ile88Leu) mutation (29 patients and 17 unaffected carriers) underwent an in-depth cardiac and neurologic evaluation at a single center.All 29 patients showed cardiac involvement. In 20 (69%) cases, it was associated with neurological abnormalities (i.e. a mixed phenotype): 10 (35% of the total) had signs and symptoms of neuropathy, 5 (17%) had abnormalities at the neurologic specialist examination but without symptoms, and 5 (17%) had abnormal nerve conduction study only. None of the asymptomatic carriers showed neurological abnormalities or cardiac involvement. The Neuropathy Impairment Score was5 in seven patients at baseline, and became5 in six more patients during follow-up. The probability of experiencing a major adverse cardiac event (MACE) during follow-up was higher in the mixed than cardiologic phenotype (At least two-thirds of patients with Ile68Leu ATTR and amyloidotic cardiomyopathy show an associated - definite or probable - neurologic impairment of variable degree if accurately evaluated in a neurologic setting. This proportion can rise during follow-up. The mixed phenotype carries a worse prognosis compared to the exclusively cardiologic one. These observations show that more patients could be eligible for treatment with gene silencers than currently indicated and highlight the need for an in-depth and continuous multidisciplinary evaluation of Ile68Leu ATTR patients

    Test and simulation of plastic scintillator strips readout by silicon photomultipliers

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    We studied the light collection in plastic scintillator strips, optimized for the detection of Minimum Ionizing Particles (MIPs). The light is collected by Wave Length Shifter (WLS) fibers and detected by Silicon Photo Multipliers (SiPMs). The study is based on prototypes developed for the muon detector of SuperB experiment. In parallel to measurement made on various type of geometries, a complete simulation suite, based on FLUKA, was developed. The simulation parameters were tuned by comparison with real data. In this way, we were able to study the effects of geometries and assembling procedures on light collection and provide a useful simulation tool for the design of future prototypes
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