507 research outputs found

    Simplified Quantum Process Characterization by Specialised Neural Networks

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    Characterization of quantum objects based on previous knowledge is a valuable approach, especially as it leads to routine procedures for real-life components. To this end, Machine Learning algorithms have demonstrated to successfully operate in presence of noise. However, there might be instances in which unknown parasitic effects occur in tandem with the sought one we aim at characterizing. Here we show that the accurate design of a two-stage neural network can account for these class of disturbances as well, applying our technique to the characterization of several quantum channels. We demonstrate that a stable and reliable characterization is achievable by training the network only with simulated data. The obtained results show the viability of this approach as an effective tool based on a completely new paradigm for the employment of NNs in the quantum domain

    Risk Attitudes to Catastrophic Events: VSL and WTP for Insurance Against Earthquakes

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    The purpose of the paper is to investigate the attitude to risk related to low-probability, high-impact events. To do this, we compare the willingness to pay (WTP) to reduce mortality risks and the WTP for life insurance against earthquakes. We explore whether risk perception affects these measures, and exploit WTP to reduce risk of fatality to calculate the Value of a Statistical Life (VSL) related to seismic events. We rely on data from a survey administered to a representative sample of the Italian population. Our results highlight that the WTP to reduce mortality risk is lower than the WTP for life insurance, and that the correlations between risk perception and these two measures differ. The findings suggest that individuals’ preferences are directed toward risk management strategies in which the mortality risk is transferred to the capital market, rather than risk mitigation strategies involving the individual in sharing the costs and benefits with all of society

    The Role of a Restorative Resource in the Academic Context in Improving Intrinsic and Extrinsic Motivation and Flow within the Job Demands–Resources Model

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    The perceived quality of the learning environment may influence both motivation and concentration. Little is known about how perceived characteristics of the learning environment, and specifically sub-dimensions of Perceived Restorativeness (being away, fascination, compatibility, and extent), can promote these positive effects in an academic context. We addressed, through a correlational study, the possibility that the characteristics of learning environments may promote concentration and involvement in activity (i.e., flow) via intrinsic and extrinsic motivation for academic study within the job demands–resources model. A total of 165 Italian university psychology classes in a 3-year degree course from two different universities context completed an online questionnaire made up of the construct considered in this study. Results in the hierarchical multivariate regression analyses confirm that the restorative quality of learning environments (i.e., being away, compatibility, extent) is positively correlated with flow. However, there is a non-significant relationship between extent and flow. Regression analyses show a significant indirect effect of compatibility, both through intrinsic and extrinsic student motivation. Furthermore, the results confirm a significant indirect effect of extent through intrinsic motivation and being away, and fascination through Extrinsic motivation. Furthermore, intrinsic motivation is a full mediator between the extent and flow relationship. The results underline the importance of considering the restorative quality of the environment for improving place design, concentration, and student learning motivation

    A cluster randomized trial to assess the impact of clinical pathways for patients with stroke: rationale and design of the Clinical Pathways for Effective and Appropriate Care Study [NCT00673491]

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    <p>Abstract</p> <p>Background</p> <p>Patients with stroke should have access to a continuum of care from organized stroke units in the acute phase, to appropriate rehabilitation and secondary prevention measures. Moreover to improve the outcomes for acute stroke patients from an organizational perspective, the use of multidisciplinary teams and the delivery of continuous stroke education both to the professionals and to the public, and the implementation of evidence-based stroke care are recommended. Clinical pathways are complex interventions that can be used for this purpose. However in stroke care the use of clinical pathways remains questionable because little prospective controlled data has demonstrated their effectiveness. The purpose of this study is to determine whether clinical pathways could improve the quality of the care provided to the patients affected by stroke in hospital and through the continuum of the care.</p> <p>Methods</p> <p>Two-arm, cluster-randomized trial with hospitals and rehabilitation long-term care facilities as randomization units. 14 units will be randomized either to arm 1 (clinical pathway) or to arm 2 (no intervention, usual care). The sample will include 238 in each group, this gives a power of 80%, at 5% significance level. The primary outcome measure is 30-days mortality. The impact of the clinical pathways along the continuum of care will also be analyzed by comparing the length of hospital stay, the hospital re-admissions rates, the institutionalization rates after hospital discharge, the patients' dependency levels, and complication rates. The quality of the care provided to the patients will be assessed by monitoring the use of diagnostic and therapeutic procedures during hospital stay and rehabilitation, and by the use of key quality indicators at discharge. The implementation of organized care will be also evaluated.</p> <p>Conclusion</p> <p>The management of patients affected by stroke involves the expertise of several professionals, which can result in poor coordination or inefficiencies in patient treatment, and clinical pathways can significantly improve the outcomes of these patients. It is proposed that this study will test a new hypothesis and provide evidence of how clinical pathways can work.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov ID [NCT00673491]</p

    Gene- and variant-specific efficacy of serum/glucocorticoid-regulated kinase 1 inhibition in long QT syndrome types 1 and 2.

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    AIMS Current long QT syndrome (LQTS) therapy, largely based on beta-blockade, does not prevent arrhythmias in all patients; therefore, novel therapies are warranted. Pharmacological inhibition of the serum/glucocorticoid-regulated kinase 1 (SGK1-Inh) has been shown to shorten action potential duration (APD) in LQTS type 3. We aimed to investigate whether SGK1-Inh could similarly shorten APD in LQTS types 1 and 2. METHODS AND RESULTS Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) and hiPSC-cardiac cell sheets (CCS) were obtained from LQT1 and LQT2 patients; CMs were isolated from transgenic LQT1, LQT2, and wild-type (WT) rabbits. Serum/glucocorticoid-regulated kinase 1 inhibition effects (300 nM-10 ”M) on field potential durations (FPD) were investigated in hiPSC-CMs with multielectrode arrays; optical mapping was performed in LQT2 CCS. Whole-cell and perforated patch clamp recordings were performed in isolated LQT1, LQT2, and WT rabbit CMs to investigate SGK1-Inh (3 ”M) effects on APD. In all LQT2 models across different species (hiPSC-CMs, hiPSC-CCS, and rabbit CMs) and independent of the disease-causing variant (KCNH2-p.A561V/p.A614V/p.G628S/IVS9-28A/G), SGK1-Inh dose-dependently shortened FPD/APD at 0.3-10 ”M (by 20-32%/25-30%/44-45%). Importantly, in LQT2 rabbit CMs, 3 ”M SGK1-Inh normalized APD to its WT value. A significant FPD shortening was observed in KCNQ1-p.R594Q hiPSC-CMs at 1/3/10 ”M (by 19/26/35%) and in KCNQ1-p.A341V hiPSC-CMs at 10 ”M (by 29%). No SGK1-Inh-induced FPD/APD shortening effect was observed in LQT1 KCNQ1-p.A341V hiPSC-CMs or KCNQ1-p.Y315S rabbit CMs at 0.3-3 ”M. CONCLUSION A robust SGK1-Inh-induced APD shortening was observed across different LQT2 models, species, and genetic variants but less consistently in LQT1 models. This suggests a genotype- and variant-specific beneficial effect of this novel therapeutic approach in LQTS

    Role of Low-Molecular-Weight Heparin in Hospitalized Patients with Severe Acute Respiratory Syndrome Coronavirus 2 Pneumonia: A Prospective Observational Study

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    Background: This study was conducted to evaluate the impact of low-molecular-weight heparin (LMWH) on the outcome of patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia. Methods: This is a prospective observational study including consecutive patients with laboratory-confirmed SARS-CoV-2 pneumonia admitted to the University Hospital of Pisa (March 4-April 30, 2020). Demographic, clinical, and outcome data were collected. The primary endpoint was 30-day mortality. The secondary endpoint was a composite of death or severe acute respiratory distress syndrome (ARDS). Low-molecular-weight heparin, hydroxychloroquine, doxycycline, macrolides, antiretrovirals, remdesivir, baricitinib, tocilizumab, and steroids were evaluated as treatment exposures of interest. First, a Cox regression analysis, in which treatments were introduced as time-dependent variables, was performed to evaluate the association of exposures and outcomes. Then, a time-dependent propensity score (PS) was calculated and a PS matching was performed for each treatment variable. Results: Among 315 patients with SARS-CoV-2 pneumonia, 70 (22.2%) died during hospital stay. The composite endpoint was achieved by 114 (36.2%) patients. Overall, 244 (77.5%) patients received LMWH, 238 (75.5%) received hydroxychloroquine, 201 (63.8%) received proteases inhibitors, 150 (47.6%) received doxycycline, 141 (44.8%) received steroids, 42 (13.3%) received macrolides, 40 (12.7%) received baricitinib, 13 (4.1%) received tocilizumab, and 13 (4.1%) received remdesivir. At multivariate analysis, LMWH was associated with a reduced risk of 30-day mortality (hazard ratio [HR], 0.36; 95% confidence interval [CI], 0.21-0.6; P &lt;.001) and composite endpoint (HR, 0.61; 95% CI, 0.39-0.95; P =.029). The PS-matched cohort of 55 couples confirmed the same results for both primary and secondary endpoint. Conclusions: This study suggests that LMWH might reduce the risk of in-hospital mortality and severe ARDS in coronavirus disease 2019. Randomized controlled trials are warranted to confirm these preliminary findings

    The impact of care pathways for exacerbation of Chronic Obstructive Pulmonary Disease: rationale and design of a cluster randomized controlled trial

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    <p>Abstract</p> <p>Background</p> <p>Hospital treatment of chronic obstructive pulmonary disease (COPD) frequently does not follow published evidences. This lack of adherence can contribute to the high morbidity, mortality and readmissions rates. The European Quality of Care Pathway (EQCP) study on acute exacerbations of COPD (NTC00962468) is undertaken to determine how care pathways (CP) as complex intervention for hospital treatment of COPD affects care variability, adherence to evidence based key interventions and clinical outcomes.</p> <p>Methods</p> <p>An international cluster Randomized Controlled Trial (cRCT) will be performed in Belgium, Italy, Ireland and Portugal. Based on the power analysis, a sample of 40 hospital teams and 398 patients will be included in the study. In the control arm of the study, usual care will be provided. The experimental teams will implement a CP as complex intervention which will include three active components: a formative evaluation of the quality and organization of care, a set of evidence based key interventions, and support on the development and implementation of the CP. The main outcome will be six-month readmission rate. As a secondary endpoint a set of clinical outcome and performance indicators (including care process evaluation and team functioning indicators) will be measured in both groups.</p> <p>Discussion</p> <p>The EQCP study is the first international cRCT on care pathways. The design of the EQCP project is both a research study and a quality improvement project and will include a realistic evaluation framework including process analysis to further understand why and when CP can really work.</p> <p>Trial Registration number</p> <p><b>NCT00962468</b></p
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