Search results for "Linear Models"
showing 10 items of 440 documents
Epoch versus impulse models in the analysis of parametric fMRI studies
2013
Abstract Objective In parametric fMRI studies the relationship between the amplitude of the hemodynamic response and electrophysiological or behavioral parameters is commonly analyzed using the general linear model (GLM). We examined ways of using single-trial response time (RT) in the analysis of a decision-making task to better isolate task-specific activation. Methods fMRI and RT data were recorded in twenty-one subjects performing a visual-oddball-task. Four explanatory variables (EVs) were generated for the GLM-analysis: A conventional (constant impulse) EV, a constant epoch EV informed using subjects’ average RT, a variable impulse EV and a variable epoch EV both informed using single…
Noninvasive measurement of intracranial pressure: Is it possible?
2007
BACKGROUND: Some publications suggest a strong correlation between the intracranial pressure and the intraocular pressure. Other studies claim no correlation between these two physiologic variables. Our aim was to study whether the tonometry could be a useful method to evaluate intracranial pressure in patients with suspected intracranial abnormality. METHODS: We evaluated the correlation between the intracranial pressure and the intraocular pressure, the intracranial pressure and the mean arterial pressure, and the intraocular pressure and the mean arterial pressure in 22 patients, initially comatose, who were admitted to our hospital. All patients required the intracranial pressure monito…
Predictors of weight loss after an intensive lifestyle intervention program in obese patients: a 1-year prospective cohort study.
2013
Published Version of an article in the journal: Health and Quality of Life Outcomes. Also available from the publisher at: http://dx.doi.org/10.1186/1477-7525-11-165 Open access Background Studies of lifestyle intervention programs in morbid obesity report large variations in weight loss outcomes. This is reported not only between but also within standardized programs. Such reports point to participants’ characteristics as possible predictors of this outcome. The aim of this prospective cohort study was to identify predictors of weight loss after a 1-year partly residential intensive lifestyle intervention program (ILI). Methods Morbidly obese patients (n=199), all Caucasian, 71% women, mea…
Effect of static foot posture on the dynamic stiffness of foot joints during walking
2018
Background The static foot posture has been related to the development of lower limb injuries. Research question This study aimed to investigate the dynamic stiffness of foot joints during gait in the sagittal plane to understand the role of the static foot posture in the development of injuries. Methods Seventy healthy adult male subjects with different static postures, assessed by the Foot Posture Index (FPI) (30 normal, 20 highly pronated and 20 highly supinated), were recruited. Kinematic and kinetic data were recorded using an optical motion capture system and a pressure platform, and dynamic stiffness at the different stages of the stance was calculated from the slopes of the linear r…
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…
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…