Search results for " Variability"
showing 10 items of 853 documents
Spectral analysis of the beat-to-beat variability of arterial compliance
2022
Arterial compliance is an important parameter influencing ventricular-arterial coupling, depending on structural and functional mechanics of arteries. In this study, the spontaneous beat-to-beat variability of arterial compliance was investigated in time and frequency domains in thirty-nine young and healthy subjects monitored in the supine resting state and during head-up tilt. Spectral decomposition was applied to retrieve the spectral content of the time series associated to low (LF) and high frequency (HF) oscillatory components. Our results highlight: (i) a decrease of arterial compliance with tilt, in agreement with previous studies; (ii) an increase of the LF power content concurrent…
Feasibility of Ultra-short Term Complexity Analysis of Heart Rate Variability in Resting State and During Orthostatic Stress
2022
In this work, we study ultra-short term (UST) complexity of Heart Rate Variability (HRV) and its agreement with analysis of standard short-term (ST) HRV recordings obtained at rest and during orthostatic stress. Conditional Entropy (CE) measures have been computed using both a linear Gaussian approximation and a more accurate model-free approach based on nearest neighbors. The agreement between UST and ST indices has been compared via statistical tests and correlation analysis, suggesting the feasibility of exploiting faster algorithms and shorter time series for detecting changes in cardiovascular control during various states.
Effects of Sicilian Opuntia ficus-indica juice on heart rate variability after a maximal exercise in young physically active women
2018
Systematic review by meta-analyses on the possible role of TNF-alpha polymorphisms in association with Alzheimer's disease.
2009
It has been hypothesized that polymorphisms of Tumor Necrosis Factor (TNF)-alpha gene affect the risk of developing Alzheimer's disease (AD). However, results of different studies are often inconsistent. Our aim was to investigate by meta-analysis the association of the common polymorphisms comprehensively defining the genetic variability of the TNF-alpha gene with AD risk. Hence, the results being stated are of a meta-analysis across studies, and that this meta-analysis does not invalidate the results of the individual studies previously performed. Seventeen studies that investigated the association between 5 TNF-alpha polymorphisms (-850, -308, -863, -238, and -1031) and AD were retrieved…
Phylodynamic Analysis and Implication of HCV Genotype 4 Variability on Antiviral Drug Response and T-Cell Recognition.
2020
Therapies for HCV care could change the prevalence and the geographic distribution of genotypes due to differences in Sustained Virologic Response (SVR). In this scenario, uncommon genotypes/subtypes, such as genotype 4, could spread from high-risk groups, replacing genotypes eradicated by antiviral drugs. Genotype eradication is also strongly influenced by the CD8+ T cell response. In this study, the genetic variability in HCV genotype 4 strains obtained from a cohort of 67 patients naï
Nationwide surveillance study of human astrovirus infections in an Italian paediatric population
2012
SUMMARYThe study investigated the genetic diversity of human astroviruses (HAstVs) detected in children hospitalized with gastroenteritis in Italy in 2008–2009. A total of 1321 faecal samples were collected in Parma (northern Italy), Bari (southern Italy), and Palermo (Sicily) and screened for the presence of HAstVs. RT–PCR amplification of a portion at the 5′-end of ORF2 allowed the detection of HAstVs in 3·95% of the patients. Four different genotypes (HAstV-1, HAstV-2, HAstV-4, HAstV-5) were found to be circulating during the study period, with HAstV-1 being the predominant type. Interestingly, a novel lineage, proposed as HAstV-2d, was found to have emerged in Parma in 2009. Investigati…
uality Evaluation of “Tardivo di Ciaculli” Mandarins in Post-Harvest Processing on an Industrial Scale Using a Portable Vis/NIR Device
2016
Abstract. Vis/NIR technology is widely used today to quickly and non-destructively evaluate fruit and vegetable qualities, and many applications have been found since the 1990s. However, no industrial-scale applications can further consolidate the use of non-destructive techniques in post-harvest processing. This study aims to test the possibility of applying vis/NIR technology in a modern citrus-processing plant to assess the damage that the fruits eventually suffer when they are processed on an industrial scale and the evolution of their key quality parameters in a period of 10 days after harvest. The spectral acquisitions were performed using a portable vis/NIR device, which operated in …
Sampling procedure in a willow plantation for chemical elements important for biomass combustion quality
2015
Willow (Salix spp.) is expected to contribute significantly to the woody bioenergy system in the future, so more information on how to sample the quality of the willow biomass is needed. The objectives of this study were to investigate the spatial variation of elements within shoots of a willow clone ‘Tordis’, and to reveal the relationship between sampling position, shoot diameters, and distribution of elements. Five Tordis willow shoots were cut into 10–50 cm sections from base to top. The ash content and concentration of twelve elements (Al, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, P, Si, and Zn) in each section were determined. The results showed large spatial variation in the distribution of mos…
“Sicilia”. Una, nessuna, centomila Sicilie / ‘Sicilia’. One, no one and one hundred thousand Sicilies
2013
Sicilia, è una rivista che ancora oggi ha molto da raccontare e insegnare, nella sua assoluta visionarietà così costantemente in bilico tra l’essere un periodico visceralmente siciliana e ancor più palermitana e l’essere una rivista internazionale, contemporanea, poliglotta, sperimentale e proiettata verso nuovi scenari. Sicilia, senza timore di potere essere tacciata di inutile campanilismo, merita di essere studiata in modo ben più approfondito di quanto sia stato fatto sinora, attraverso un’attenta analisi condotta nei diversi ambiti disciplinari coinvolti tra le pieghe delle sue pagine. In questa sede proveremo ad approfondire il suo studio analizzando la rivista, quale complesso artefa…
Simulation of the effects of climate change on barley yields in rural Italy
2009
The Greenhouse effect is considered to be one of the most influential factors on climate change today, especially where temperature and rainfall levels/distribution are concerned, making it of considerable importance in the field of Agronomy. Crop growth and development simulation models are a valuable cognitive tool in understanding water and nutrient dynamics in soil/plant systems. This paper looks at the direct and indirect effects of climatic changes on average barley yields. The complex nature of the study rendered the use of mathematical simulation models essential, both for predicting future climate conditions and for the simulation of crop growth and development. Of the different si…