1,409 research outputs found

    Steering a quantum system over a Schroedinger bridge

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    A new approach to the steering problem for quantum systems relying on Nelson's stochastic mechanics and on the theory of Schroedinger bridges is presented. The method is illustrated by working out a simple Gaussian example.Comment: Proc. Intern. Conf. on the Mathematical Theory of Networks and Systems, Perpignan, France, June 2000, CD-ROM, paper nr. 268, M. Fliess and A. El Jai Ed

    Coefficient of thermal expansion of nanostructured tungsten based coatings assessed by thermally induced substrate curvature method

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    The in plane coefficient of thermal expansion (CTE) and the residual stress of nanostructured W based coatings are extensively investigated. The CTE and the residual stresses are derived by means of an optimized ad-hoc developed experimental setup based on the detection of the substrate curvature by a laser system. The nanostructured coatings are deposited by Pulsed Laser Deposition. Thanks to its versatility, nanocrystalline W metallic coatings, ultra-nano-crystalline pure W and W-Tantalum coatings and amorphous-like W coatings are obtained. The correlation between the nanostructure, the residual stress and the CTE of the coatings are thus elucidated. We find that all the samples show a compressive state of stress that decreases as the structure goes from columnar nanocrystalline to amorphous-like. The CTE of all the coatings is higher than the one of the corresponding bulk W form. In particular, as the grain size shrinks, the CTE increases from 5.1 10−6^{-6} K−1^{-1} for nanocrystalline W to 6.6 10−6^{-6} K−1^{-1} in the ultra-nano-crystalline region. When dealing with amorphous W, the further increase of the CTE is attributed to a higher porosity degree of the samples. The CTE trend is also investigated as function of materials stiffness. In this case, as W coatings become softer, the easier they thermally expand.Comment: The research leading to these results has also received funding from the European Research Council Consolidator Grant ENSURE (ERC-2014-CoG No. 647554

    Environmental impact of a new concept of food service: A case study for the re-use of naval shipping containers

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    This study aims to evaluate the environmental sustainability of a new street food format for food service based on the re-use of naval shipping containers and to compare it with the conventional one (street food truck). The environmental impact analysis was performed using the Life Cycle Assessment methodology. The functional unit (FU) was identified in the food service, including three food preparations: a dish of pasta (100 g), one sandwich (150 g) and one portion of fries (200 g). Following a \u201cfrom cradle to gate\u201d approach, the factors studied are: (i) the customization of a shipping container in a street food format, (ii) the construction and use of the cooking appliance, (iii) the logistics, (iv) the cooking phase (including final packaging as food cup). The life cycle of ingredients for food preparations has been neglected due to the variability of the products. The results show that the two higher hotspots are electricity consumed by cooking appliance (35%) and oil used to fry (34%), attributable only to the fries preparation. The third hotspot is imputable to the customized structure, with an average percentage value equal to 15%. Considering the global warming impact category, the customization into a street food format release 1280 kg CO2eq, while the production of a new container or a new street food truck format implies the emission of 12,800 kg CO2eq and 20,900 kg CO2eq respectively. The impact of the customized container (re-used container) weight for 0.04 kg CO2eq/FU, this value increases 11.6 times for a new container street food format, and 17 times for a new street food truck format. Overall, quantifying the environmental damage, the results showed how the re-use of a naval shipping container can be a way to reduce the environmental impact of food preparation, avoiding dismissing or building activity of the structure reducing the impact of the structure of about 95% offering a more sustainable street food services

    The impact of COVID-19 quarantine on mental health: an observational study from an outpatient service for non-psychotic patients in Russia (Moscow)

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    We aimed to compare psychiatric hospital visits during the COVID-19 quarantine period with the same period in 2019, to reveal the predictors of underutilization of mental health services. We then investigated the fluctuation of telemedicine service during the quarantine period. The retrospective study included patients with non-psychotic mental disorders who consecutively visited the Moscow clinic. The number of outpatient visits, inpatient admissions, sociodemographic factors were analyzed. We assessed the sample within two periods -the "quarantine period" (March 30 -June 9, 2020) and "control period" (March 30 -June 9, 2019). Psychiatric visits decreased in older, retired and disabled persons, and increased among the unemployed. In multivariate analysis, the reduction became significant for the number of inpatient admissions. Telemedicine calls gradually increased from the start of the service, but decreased towards the end of the quarantine. In conclusion, referrals to outpatient and inpatient psychiatric services decreased during the quarantine period, with newly established TMS potentially compensating for that decrease. The strongest factor associated with visits during the pandemic is employment status

    Risk of Guillain-Barré syndrome after 2010–2011 influenza vaccination

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    Influenza vaccination has been implicated in Guillain Barré Syndrome (GBS) although the evidence for this link is controversial. A case–control study was conducted between October 2010 and May 2011 in seven Italian Regions to explore the relation between influenza vaccination and GBS. The study included 176 GBS incident cases aged ≥18 years from 86 neurological centers. Controls were selected among patients admitted for acute conditions to the Emergency Department of the same hospital as cases. Each control was matched to a case by sex, age, Region and admission date. Two different analyses were conducted: a matched case–control analysis and a self-controlled case series analysis (SCCS). Case–control analysis included 140 cases matched to 308 controls. The adjusted matched odds ratio (OR) for GBS occurrence within 6 weeks after influenza vaccination was 3.8 (95 % CI: 1.3, 10.5). A much stronger association with gastrointestinal infections (OR = 23.8; 95 % CI 7.3, 77.6) and influenza-like illness or upper respiratory tract infections (OR = 11.5; 95 % CI 5.6, 23.5) was highlighted. The SCCS analysis included all 176 GBS cases. Influenza vaccination was associated with GBS, with a relative risk of 2.1 (95 % CI 1.1, 3.9). According to these results the attributable risk in adults ranges from two to five GBS cases per 1,000,000 vaccinations

    Optimization of the geometrical stability in square ring laser gyroscopes

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    Ultra sensitive ring laser gyroscopes are regarded as potential detectors ofthe general relativistic frame-dragging effect due to the rotation of theEarth: the project name is GINGER (Gyroscopes IN GEneral Relativity), aground-based triaxial array of ring lasers aiming at measuring the Earthrotation rate with an accuracy of 10^-14 rad/s. Such ambitious goal is nowwithin reach as large area ring lasers are very close to the necessarysensitivity and stability. However, demanding constraints on the geometricalstability of the laser optical path inside the ring cavity are required. Thuswe have started a detailed study of the geometry of an optical cavity, in orderto find a control strategy for its geometry which could meet the specificationsof the GINGER project. As the cavity perimeter has a stationary point for thesquare configuration, we identify a set of transformations on the mirrorpositions which allows us to adjust the laser beam steering to the shape of asquare. We show that the geometrical stability of a square cavity stronglyincreases by implementing a suitable system to measure the mirror distances,and that the geometry stabilization can be achieved by measuring the absolutelengths of the two diagonals and the perimeter of the ring

    The GINGER Project and status of the ring-laser of LNGS

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    A ring-laser attached to the Earth measures the absolute angular velocity of the Earth summed to the relativistic precessions, de Sitter and Lense-Thirring. GINGER (Gyroscopes IN GEneral Relativity) is a project aiming at measuring the LenseThirring effect with a ground based detector; it is based on an array of ring-lasers. Comparing the Earth angular velocity measured by IERS and the measurement done with the GINGER array, the Lense-Thirring effect can be evaluated. Compared to the existing space experiments, GINGER provides a local measurement, not the averaged value and it is unnecessary to model the gravitational field. It is a proposal, but it is not far from being a reality. In fact the GrossRing G of the Geodesy Observatory of Wettzell has a sensitivity very close to the necessary one. G ofWettzell is part of the IERS system which provides the measure of the Length Of the DAY (LOD); G provides information on the fast component of LOD. In the last few years, a roadmap toward GINGER has been outlined. The experiment G-GranSasso, financed by the INFN Commission II, is developing instrumentations and tests along the roadmap of GINGER. In this short paper the main activities of G-GranSasso and some results will be presented. The first results of GINGERino will be reported, GINGERino is the large ring-laser installed inside LNGS and now in the commissioning phase. Ring-lasers provide as well important informations for geophysics, in particular the rotational seismology, which is an emerging field of science. GINGERino is one of the three experiments of common interest between INFN and INGV

    Risk of seizure recurrence in people with single seizures and early epilepsy - Model development and external validation

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    PURPOSE: Following a single seizure, or recent epilepsy diagnosis, it is difficult to balance risk of medication side effects with the potential to prevent seizure recurrence. A prediction model was developed and validated enabling risk stratification which in turn informs treatment decisions and individualises counselling. METHODS: Data from a randomised controlled trial was used to develop a prediction model for risk of seizure recurrence following a first seizure or diagnosis of epilepsy. Time-to-event data was modelled via Cox's proportional hazards regression. Model validity was assessed via discrimination and calibration using the original dataset and also using three external datasets - National General Practice Survey of Epilepsy (NGPSE), Western Australian first seizure database (WA) and FIRST (Italian dataset of people with first tonic-clonic seizures). RESULTS: People with neurological deficit, focal seizures, abnormal EEG, not indicated for CT/MRI scan, or not immediately treated have a significantly higher risk of seizure recurrence. Discrimination was fair and consistent across the datasets (c-statistics: 0.555 (NGPSE); 0.558 (WA); 0.597 (FIRST)). Calibration plots showed good agreement between observed and predicted probabilities in NGPSE at one and three years. Plots for WA and FIRST showed poorer agreement with the model underpredicting risk in WA, and over-predicting in FIRST. This was resolved following model recalibration. CONCLUSION: The model performs well in independent data especially when recalibrated. It should now be used in clinical practice as it can improve the lives of people with single seizures and early epilepsy by enabling targeted treatment choices and more informed patient counselling

    Long-term prognosis of epilepsy, prognostic patterns and drug resistance: a population-based study

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    BACKGROUND AND PURPOSE: Seizures in most people with epilepsy remit but prognostic markers are poorly understood. There is also little information on the long-term outcome of people who fail to achieve seizure control despite the use of two antiepileptic drugs (drug resistance). METHODS: People with a validated diagnosis of epilepsy in whom two antiepileptic drugs had failed were identified from primary care records. All were registered with one of 123 family physicians in an area of northern Italy. Remission (uninterrupted seizure freedom lasting 2 years or longer) and prognostic patterns (early remission, late remission, remission followed by relapse, no remission) were determined. RESULTS: In all, 747 individuals (381 men), aged 11 months to 94 years, were followed for 11 045.5 person-years. 428 (59%) were seizure-free. The probability of achieving 2-year remission was 18% at treatment start, 34% at 2 years, 45% at 5, 52% at 10 and 67% at 20 years (terminal remission, 60%). Epilepsy syndrome and drug resistance were the only independent predictors of 2- and 5-year remission. Early remission was seen in 101 people (19%), late remission in 175 (33%), remission followed by relapse in 85 (16%) and no remission in 166 (32%). Treatment response was the only variable associated with differing prognostic patterns. CONCLUSION: The long-term prognosis of epilepsy is favourable in most cases. Early seizure remission is not invariably followed by terminal remission and seizure outcome varies according to well-defined patterns. Prolonged seizure remission and prognostic patterns can be predicted by broad syndromic categories and the failure of two antiepileptic drugs
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