Local Temperature and Universal Heat Conduction in FPU chains

It is shown numerically that for Fermi Pasta Ulam (FPU) chains with alternating masses and heat baths at slightly different temperatures at the ends, the local temperature (LT) on small scales behaves paradoxically in steady state. This expands the long established problem of equilibration of FPU chains. A well-behaved LT appears to be achieved for equal mass chains; the thermal conductivity is shown to diverge with chain length N as N^(1/3), relevant for the much debated question of the universality of one dimensional heat conduction. The reason why earlier simulations have obtained systematically higher exponents is explained.Comment: 4 pages, 3 figures, revised published versio

A Bayesian Sample Size Estimation Procedure Based on a B-Splines Semiparametric Elicitation Method

Sample size estimation is a fundamental element of a clinical trial, and a binomial experiment is the most common situation faced in clinical trial design. A Bayesian method to determine sample size is an alternative solution to a frequentist design, especially for studies conducted on small sample sizes. The Bayesian approach uses the available knowledge, which is translated into a prior distribution, instead of a point estimate, to perform the final inference. This procedure takes the uncertainty in data prediction entirely into account. When objective data, historical information, and literature data are not available, it may be indispensable to use expert opinion to derive the prior distribution by performing an elicitation process. Expert elicitation is the process of translating expert opinion into a prior probability distribution. We investigated the estimation of a binomial sample size providing a generalized version of the average length, coverage criteria, and worst outcome criterion. The original method was proposed by Joseph and is defined in a parametric framework based on a Beta-Binomial model. We propose a more flexible approach for binary data sample size estimation in this theoretical setting by considering parametric approaches (Beta priors) and semiparametric priors based on B-splines

Incidence and prevalence analysis of non-small-cell and small-cell lung cancer using administrative data

Treatment of lung cancer depends on the stage of the tumor and the histological type. In recent years, the histological confirmation of lung non-small-cell lung cancer has become crucial since the availability of selective target therapeutic approaches. The aim of the study was to develop a validated procedure to estimate the incidence and prevalence of non-small-cell and small-cell lung cancer from healthcare administrative data. A latent class model for categorical variables was applied. The following observed variables were included in the analysis: ICD-9-CM codes in the Hospital Discharge Registry, ATC codes of medications dispensed present in the Drugs Prescriptions Registry, and the procedure codes in the Outpatient Registry. The proportion of non-small-cell lung cancer diagnoses was estimated to be 85% of the total number of lung cancer on the cohort of incident cases and 89% on the cohort of prevalent cases. External validation on a cohort of 107 patients with a lung cancer diagnosis and histological confirmation showed a sensitivity of 95.6% (95%CI: 89–98.8%) and specificity of 94.1% (95%CI: 71.3–99.9%). The procedure is an easy-to-use tool to design subpopulation-based studies on lung cancer and to better plan resource allocation, which is important since the introduction of new targeted therapies in non-small-cell lung carcinoma

The Severe Heart Failure Questionnaire: Italian translation and linguistic validation

Introduction. The quality of life (QoL) is an important outcome indicator for heart failure management. As the use of a validate questionnaire in a different cultural context can affect data interpretation our main objective is the Italian translation and linguistic validation of the Severe Heart Failure Questionnaire (SHF) and its comparison with the MLHF (Minnesota Living with Heart Failure) Questionnaire. Methods. The SHF and ?The Minnesota Living with Heart Failure Questionnaire? were translated. A consensus involving parallel back-translations was established among a group of cardiologists, psychologists and biostatisticians. SHF and MLHF were both administrated to a sample of 50 patients Results. The patients? median age was 63 years. Ace inhibitors therapy was administered in 88% of cases and betablockers in 56% of cases. Finally the Italian version of SHF correlates well with MLHF for all domains, except life satisfaction SHF domain. Discussion: The Italian version of the SHF correlates well with MLHF for almost all domains and it represents a valid alterna- tive for quality of life assessment in heart failure patients

Is a more aggressive COVID-19 case detection approach mitigating the burden on ICUs? Some reflections from Italy

No abstract availabl