Search results for "linear"
showing 10 items of 7165 documents
Prediction of arch length based on intercanine width.
2008
Arch length (AL), intercanine width (ICW), and intermolar width (IMW) are essential for diagnosis and treatment planning and are closely related factors in orthodontics. The aim of the present study was to determine correlations between these measurements and to predict some of these measurements based on others. The dental casts of 197 Spanish patients (119 females and 78 males) with a mean age of 18 years (11-26 years) in the permanent dentition attending the Orthodontic Department of the University of Valencia, Spain, were selected. ICW, IMW, and AL on each dental cast were measured using a previously tested digital method. Correlation between variables was determined using Pearson's cor…
Oxidative status in nondiabetic middle-aged subjects with metabolic syndrome: preliminary data.
2013
Increase in Regular Leisure-Time Physical Activity in Spanish Adults Between 1987 and 2017.
2021
Introduction:\ud \ud The prevalence of leisure-time physical activity has increased in recent decades, but values differ significantly among countries. Owing to the improvement of living standards, a higher frequency of leisure-time physical activity is expected in Western countries such as Spain, but there is a lack of research involving large, representative samples during a prolonged temporal frame to confirm this tendency.\ud \ud Methods:\ud \ud Individual representative data from the 1987, 1993, 1995, 1997, 2001, 2011, and 2017 rounds of the Spanish National Health Survey were used. Statistical analyses were conducted from April 9, 2020 to May 5, 2020.\ud \ud Results:\ud \ud A total of…
Comparison of Methods for the Assessment of Nonlinearity in Short-Term Heart Rate Variability under different Physiopathological States
2019
Despite the widespread diffusion of nonlinear methods for heart rate variability (HRV) analysis, the presence and the extent to which nonlinear dynamics contribute to short-term HRV are still controversial. This work aims at testing the hypothesis that different types of nonlinearity can be observed in HRV depending on the method adopted and on the physiopathological state. Two entropy-based measures of time series complexity (normalized complexity index, NCI) and regularity (information storage, IS), and a measure quantifying deviations from linear correlations in a time series (Gaussian linear contrast, GLC), are applied to short HRV recordings obtained in young (Y) and old (O) healthy su…
Influence of social cognition as a mediator between cognitive reserve and psychosocial functioning in patients with first episode psychosis
2019
This work was supported by the Carlos III Institute of Health and European Fund for Regional Development (PI08/1213, PI11/01977, PI14/01900, PI08/01026, PI11/02831, PI14/01621, PI08/1161, PI16/00359, PI16/01164, PI18/00805), the Basque Foundation for Health Innovation and Research (BIOEF), the Secretaria d´Universitats I Recerca del Departament d´Economia I Coneixement (2017 SGR 1365), and R&D activities in Biomedicine, Madrid Regional Government and Structural Funds of the European Union (S2017/BMD-3740 (AGES-CM 2-CM)).
Causal transfer function analysis to describe closed loop interactions between cardiovascular and cardiorespiratory variability signals
2004
Although the concept of transfer function is intrinsically related to an input-output relationship, the traditional and widely used estimation method merges both feedback and feedforward interactions between the two analyzed signals. This limitation may endanger the reliability of transfer function analysis in biological systems characterized by closed loop interactions. In this study, a method for estimating the transfer function between closed loop interacting signals was proposed and validated in the field of cardiovascular and cardiorespiratory variability. The two analyzed signals x and y were described by a bivariate autoregressive model, and the causal transfer function from x to y w…
Deterministic chaos and the first positive Lyapunov exponent: a nonlinear analysis of the human electroencephalogram during sleep
1993
Under selected conditions, nonlinear dynamical systems, which can be described by deterministic models, are able to generate so-called deterministic chaos. In this case the dynamics show a sensitive dependence on initial conditions, which means that different states of a system, being arbitrarily close initially, will become macroscopically separated for sufficiently long times. In this sense, the unpredictability of the EEG might be a basic phenomenon of its chaotic character. Recent investigations of the dimensionality of EEG attractors in phase space have led to the assumption that the EEG can be regarded as a deterministic process which should not be mistaken for simple noise. The calcu…
Association Between Low Education and Higher Global Cardiovascular Risk
2014
This study was designed to evaluate the impact of educational status on global cardiovascular risk in a southern Italian urban population. The study population consisted of 488 consecutive outpatients aged 18 years and older. Educational status was categorized according to the number of years of formal education as follows: (1) low education group (10 years) and (2) medium-high education group (10-15 years). In both groups, cardiometabolic comorbidities (obesity, visceral obesity, diabetes, dyslipidemia, metabolic syndrome, microalbuminuria, left ventricular hypertrophy) and global cardiovascular risk, according to international guidelines, were analyzed. Left ventricular mass index and eje…
Psychotic-like experiences in the general population of Buenos Aires city
2011
Impaired Health-Related Quality of Life in Inflammatory Bowel Diseases Psychosocial Impact and Coping Styles in a National German Sample
2001
The purpose of this study is to give a detailed survey of the disease-specific and generic quality of life (HRQOL) of adult patients suffering from inflammatory bowel disease (IBD) in Germany.1322 patients suffering from IBD were examined in a cross-sectional study. A questionnaire assessing disease-specific and generic quality of life, coping, and hopelessness was sent to members of the German Crohn/Colitis association.Compared to the general population, the generic HRQOL in IBD patients is significantly reduced. Active coping has a negative influence on patients' generic physical HRQOL during an active phase (beta = -0.31), while this association is not present in the case of patients in …