Search results for "Linea"
showing 10 items of 7724 documents
The calculation of the first positive Lyapunov exponent in sleep EEG data
1993
To help determine if the EEG is quasiperiodic or chaotic we performed a new analysis by calculating the first positive Lyapunov exponent L1 from sleep EEG data. Lyapunov exponents measure the mean exponential expansion or contraction of a flow in phase space. L1 is zero for periodic as well as quasiperiodic processes, but positive in case of chaotic processes expressing the sensitive dependence on initial conditions. We calculated L1 for sleep EEG segments of 15 healthy male subjects corresponding to sleep stages I, II, III, IV and REM (according to Rechtschaffen and Kales). Our investigations support the assumption that EEG signals are neither quasiperiodic waves nor simple noise. Moreover…
Quantifying Net Synergy/Redundancy of Spontaneous Variability Regulation via Predictability and Transfer Entropy Decomposition Frameworks.
2017
Objective: Indexes assessing the balance between redundancy and synergy were hypothesized to be helpful in characterizing cardiovascular control from spontaneous beat-to-beat variations of heart period (HP), systolic arterial pressure (SAP), and respiration (R). Methods: Net redundancy/synergy indexes were derived according to predictability and transfer entropy decomposition strategies via a multivariate linear regression approach. Indexes were tested in two protocols inducing modifications of the cardiovascular regulation via baroreflex loading/unloading (i.e., head-down tilt at −25° and graded head-up tilt at 15°, 30°, 45°, 60°, 75°, and 90°, respectively). The net redundancy/synergy of …
Physical activity and quality of cardiopulmonary resuscitation: A secondary analysis of the MANI-CPR trial
2021
Abstract Introduction The association between the level of physical activity and quality of cardio-pulmonary resuscitation (CPR) performed by laypeople is unclear. The aim of this study was to evaluate the associations between physical activity level and laypeople performance during an eight-minute scenario of CPR. Materials and methods This study was a secondary analysis of the MANI-CPR Trial. The entire cohort of participants was grouped based on the level of physical activity assessed using the International Physical Activity Questionnaire (IPAQ) into a “low-moderate” level group and a “high” level group. Descriptive statistics were used for unadjusted analysis and multivariate logistic …
Neural correlates of interference inhibition, action withholding and action cancelation in adult ADHD
2011
Attention-Deficit/Hyperactivity Disorder (ADHD) is marked by inhibitory and attentional deficits which can persist into adulthood. Those deficits have been associated with dysfunctional fronto-striatal and fronto-parietal circuits. The present study sought to delineate neural correlates of component specific inhibitory deficits in adult ADHD using functional magnetic resonance imaging (fMRI). 20 adult ADHD patients and 24 matched healthy controls were included. Brain activation was assessed during three stages of behavioral inhibition, i.e. interference inhibition (Simon task), action withholding (Go/no-go task) and action cancelation (Stop-signal task). Behaviorally, ADHD patients were aff…
Olfactory categorization: a developmental study.
2012
International audience; This study examined the ability of children to classify fruit and flower odors. We asked four groups of children (4-11 years of age) and a group of adults to identify, categorize, and evaluate the edibility, liking, and typicality of 12 fruit and flower odors. Results showed an increase in interindividual agreement with age for the taxonomic (fruit/flower) and function-based (edible/nonedible) categories but not for the hedonic component. So, it seems that this hedonic component is not the explicit basis for this increase in interindividual agreement when categorizing an odor as a fruit/flower odor or as being edible or nonedible. An age-related trend was also observ…
The effect of olive oil polyphenols on antibodies against oxidized LDL. A randomized clinical trial
2010
summary Background & aim: Oxidized LDL (oxLDL) is a highly immunogenic particle that plays a key role in the development of atherosclerosis. Some data suggest a protective role of OxLDL autoantibodies (OLAB) in atherosclerosis. Our aim was to assess the effect of olive oil polyphenols on the immunogenicity of oxLDL to autoantibody generation. Methods: In a crossover, controlled trial, 200 healthy men were randomly assigned to 3-week sequences of 25 mL/day of 3 olive oils with high (366 mg/kg), medium (164 mg/kg), and low (2.7 mg/kg) phenolic content. Results: Plasma OLAB concentration was inversely associated with oxLDL (p < 0.001). Olive oil phenolic content increased OLAB generation, with…
Brain atrophy and lesion load in a large population of patients with multiple sclerosis
2005
Objective: To measure white matter (WM) and gray matter (GM) atrophy and lesion load in a large population of patients with multiple sclerosis (MS) using a fully automated, operator-independent, multiparametric segmentation method. Methods: The study population consisted of 597 patients with MS and 104 control subjects. The MRI parameters were abnormal WM fraction (AWM-f), global WM-f (gWM-f), and GM fraction (GM-f). Results: Significant differences between patients with MS and control subjects included higher AWM-f and reduced gWM-f and GM-f. MRI data showed significant differences between patients with relapsing-remitting and secondary progressive forms of MS. Significant correlations bet…
Feasibility, reproducibility, and reliability for the T*2 iron evaluation at 3 T in comparison with 1.5 T
2012
This study aimed to determine the feasibility, reproducibility, and reliability of the multiecho T * 2 Magnetic resonance imaging technique at 3 T for myocardial and liver iron burden quantification and the relationship between T * 2 values at 3 and 1.5 T. Thirty-eight transfusion-dependent patients and 20 healthy subjects were studied. Cardiac segmental and global T * 2 values were calculated after developing a correction map to compensate the artifactual T * 2 variations. The hepatic T * 2 value was determined over a region of interest. The intraoperator and interoperator reproducibility for T * 2 measurements at 3 T was good. A linear relationship was found between patients' R (1000/T * …
Circulating 25-Hydroxyvitamin D3 in Pregnancy and Infant Neuropsychological Development
2012
OBJECTIVE:To investigate whether circulating 25-hydroxyvitamin D3 [25(OH)D3] concentration in pregnancy is associated with neuropsychological development in infants.METHODS:The Spanish population-based cohort study INfancia y Medio Ambiente Project recruited pregnant women during the first trimester of pregnancy between November 2003 and February 2008. Completed data on 1820 mother-infant pairs were used. Maternal plasma 25(OH)D3 concentration was measured by high-performance liquid chromatography in pregnancy (mean 13.5±2.1 weeks of gestation). Offspring mental and psychomotor scores were assessed by trained psychologists at age 14 months (range, 11–23) by using the Bayley Scales of Infant…
Associations of Birth Weight and Postnatal Weight Gain With Cardiometabolic Risk Parameters at 5 Years of Age
2014
The present prospective study assessed the impact of birth weight (BW) and postnatal weight gain on blood pressure and metabolic profile during the first 5 years of life. One hundred thirty-nine newborns (63 women) born at term after uncomplicated pregnancies and in the absence of perinatal illness were included. Subjects were divided according to size at birth in small, appropriate, and large for gestational age. After the initial evaluation on the second day of life, infants were followed up at 6 months and 2 and 5 years. Anthropometric parameters and blood pressure were measured at each visit and metabolic assessment was performed at 5 years of age. Among the BW groups, mothers did not d…