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1.
Sensors (Basel) ; 24(11)2024 May 24.
Article in English | MEDLINE | ID: mdl-38894170

ABSTRACT

We present a novel decision-making framework for accelerated degradation tests and predictive maintenance that exploits prior knowledge and experimental data on the system's state. As a framework for sequential decision making in these areas, dynamic programming and reinforcement learning are considered, along with data-driven degradation learning when necessary. Furthermore, we illustrate both stochastic and machine learning degradation models, which are integrated in the framework, using data-driven methods. These methods are presented as a valuable tool for designing life-testing experiments and for maintaining lithium-ion batteries.

2.
Multivariate Behav Res ; 58(6): 1160-1164, 2023.
Article in English | MEDLINE | ID: mdl-37038660

ABSTRACT

This article proposes the Shiny app 'CLC Estimator' -Congeneric Latent Construct Estimator- to address the problem of estimating latent unidimensional constructs via congeneric approaches. While congeneric approaches provide more rigorous results than suboptimal parallel-based scoring methods, most statistical packages do not provide easy access to congeneric approaches. To address this issue, the CLC Estimator allows social scientists to use congeneric approaches to estimate latent unidimensional constructs smoothly. The present app provides a novel solution to the challenge of limited access to congeneric estimation methods in survey research.


Subject(s)
Research Design , Monte Carlo Method
3.
Qual Quant ; : 1-26, 2022 Sep 08.
Article in English | MEDLINE | ID: mdl-36097442

ABSTRACT

In this article, we propose a formative-reflective scheme for the assessment of Tourism Destination Competitiveness (TDC) based on a combined use of Partial Least Squares-Path Modelling (PLS-PM) and the method recently proposed by Fattore, Pelagatti, and Vittadini (FPV). TDC is conceived as a construct reflecting the tourism performance of a destination, and several determinants are considered, including endowed resources, created resources, and supporting factors. The proposed scheme is applied to a case study on 1575 Italian municipalities for which the Italian National Institute of Statistics released data on tourist flows. Our contribution is innovative for three aspects: (i) the consistency of the formative-reflective scheme for TDC assessment is discussed on a theoretical basis; (ii) an empirical comparison between PLS-PM and the FPV method is performed; (iii) data with higher granularity than most studies on TDC assessment are employed. Our findings highlight that endowed resources are the primary driver of TDC, followed by created resources and supporting factors, and emphasize that the best ranked destinations are big cities with a multifaceted tourism alongside sea and mountain destinations with cultural attractions.

4.
Eur J Nutr ; 59(5): 2011-2024, 2020 Aug.
Article in English | MEDLINE | ID: mdl-31292752

ABSTRACT

PURPOSE: We evaluated the effect of low-calorie mediterranean (MD) and vegetarian (VD) diets on gut microbiome (GM) composition and short-chain-fatty acids (SCFA) production. METHODS: We performed next generation sequencing (NGS) of 16S rRNA and SCFA analysis on fecal samples of 23 overweight omnivores (16 F; 7 M) with low-to-moderate cardiovascular risk. They were randomly assigned to a VD or MD, each lasting 3 months, with a crossover study design. RESULTS: Dietary interventions did not produce significant diversity in the GM composition at higher ranks (family and above), neither between nor within MD and VD, but they did it at genus level. MD significantly changed the abundance of Enterorhabdus, Lachnoclostridium and Parabacteroides, while VD significantly affected the abundance of Anaerostipes, Streptococcus, Clostridium sensu stricto, and Odoribacter. Comparison of the mean variation of each SCFA between MD and VD showed an opposite and statistically significant trend for propionic acid (+ 10% vs - 28%, respectively, p = 0.034). In addition, variations of SCFA were negatively correlated with changes of some inflammatory cytokines such as VEGF, MCP-1, IL-17, IP-10 and IL-12, only after MD. Finally, correlation analyses showed a potential relationship-modulated by the two diets-between changes of genera and changes of clinical and biochemical parameters. CONCLUSIONS: A short-term dietary intervention with MD or VD does not induce major change in the GM, suggesting that a diet should last longer than 3 months for scratching the microbial resilience. Changes in SCFA production support their role in modulating the inflammatory response, thus mediating the anti-inflammatory and protective properties of MD.


Subject(s)
Diet, Mediterranean , Gastrointestinal Microbiome , Cross-Over Studies , Diet, Vegetarian , Humans , RNA, Ribosomal, 16S/genetics
5.
Breast ; 40: 85-91, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29709729

ABSTRACT

AIM: Male breast cancer (MBC) is a rare disease and recommendations for its clinical management are often extrapolated from those for female breast cancer, even if breast cancer (BC) has different characteristics in the two sexes. The purpose of this study was to assess the influence of several individual characteristics including clinico-pathological, lifestyle and genetic factors on overall survival (OS) of a relatively large and well characterized population-based series of 166 MBCs enrolled in Tuscany. METHODS: We genotyped MBC cases at BRCA1/2 genes and at 9 candidate BC susceptibility SNPs. Kaplan-Meier method and multivariate Cox regression, adjusted for several individual characteristics were used. To reduce a possible selection bias related to the interval between diagnosis and enrolment of MBC cases into the study, we used the date of blood donation as the date of the start of observation for survival analysis. RESULTS: Only smoking habits had a significant effect on OS at 10 years (for current smokers, HR: 3.34; 95% CI 1.45-7.68; p = 0.004), while lymph node status fell short of reaching statistical significance (for pN positive, HR: 2.07; 95% CI 0.93-4.55; p = 0.07). In the same multivariate analysis we found a significantly higher OS in cases with FGFR2 rs2981582 variant in the dominant transmission model (HR: 0.29; 95% CI: 0.13-0.62; p = 0.028). A sensitivity analysis with left truncation showed similar results. CONCLUSIONS: Our results may contribute to shed light on factors influencing MBC survival suggesting an important role for cigarette smoking and FGFR2 rs2981582 variant, and provide clues for better patient management.


Subject(s)
Breast Neoplasms, Male/genetics , Breast Neoplasms, Male/mortality , Cigarette Smoking/genetics , Receptor, Fibroblast Growth Factor, Type 2/genetics , Adult , Aged , Aged, 80 and over , Genes, BRCA1 , Genes, BRCA2 , Genetic Association Studies , Genetic Predisposition to Disease , Genotype , Humans , Italy , Kaplan-Meier Estimate , Male , Middle Aged , Multivariate Analysis , Polymorphism, Single Nucleotide , Proportional Hazards Models , Regression Analysis , Young Adult
6.
Biom J ; 60(1): 174-195, 2018 01.
Article in English | MEDLINE | ID: mdl-29029359

ABSTRACT

In this paper, the development of a probabilistic network for the diagnosis of acute cardiopulmonary diseases is presented in detail. A panel of expert physicians collaborated to specify the qualitative part, which is a directed acyclic graph defining a factorization of the joint probability distribution of domain variables into univariate conditional distributions. The quantitative part, which is a set of parametric models defining these univariate conditional distributions, was estimated following the Bayesian paradigm. In particular, we exploited an original reparameterization of Beta and categorical logistic regression models to elicit the joint prior distribution of parameters from medical experts, and updated it by conditioning on a dataset of hospital records via Markov chain Monte Carlo simulation. Refinement was iteratively performed until the probabilistic network provided satisfactory concordance index values for several acute diseases and reasonable diagnosis for six fictitious patient cases. The probabilistic network can be employed to perform medical diagnosis on a total of 63 diseases (38 acute and 25 chronic) on the basis of up to 167 patient findings.


Subject(s)
Biometry/methods , Heart Diseases/diagnosis , Lung Diseases/diagnosis , Acute Disease , Hospitals , Humans , Monte Carlo Method , Probability
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