Search results for "Linear Model"
showing 10 items of 598 documents
Echocardiographic reference ranges for normal left ventricular 2D strain: results from the EACVI NORRE study
2017
International audience; Aims - To obtain the normal ranges for 2D echocardiographic (2DE) measurements of left ventricular (LV) strain from a large group of healthy volunteers accounting for age and gender. Methods and results - A total of 549 (mean age: 45.6 ± 13.3 years) healthy subjects were enrolled at 22 collaborating institutions of the Normal Reference Ranges for Echocardiography (NORRE) study. 2DE data sets have been analysed with a vendor-independent software package allowing homogeneous measurements irrespective of the echocardiographic equipment used to acquire the data sets. The lowest expected values of LV strains and twist calculated as ± 1.96 standard deviations from the mean…
A topological substructural approach for the prediction of P-glycoprotein substrates
2006
A topological substructural molecular design approach (TOPS-MODE) has been used to predict whether a given compound is a P-glycoprotein (P-gp) substrate or not. A linear discriminant model was developed to classify a data set of 163 compounds as substrates or nonsubstrates (91 substrates and 72 nonsubstrates). The final model fit the data with sensitivity of 82.42% and specificity of 79.17%, for a final accuracy of 80.98%. The model was validated through the use of an external validation set (40 compounds, 22 substrates and 18 nonsubstrates) with a 77.50% of prediction accuracy; fivefold full cross-validation (removing 40 compounds in each cycle, 80.50% of good prediction) and the predictio…
Effects of comprehensive geriatric intervention on physical performance among people aged 75 years and over.
2012
Background and aims: We studied the effects of comprehensive geriatric assessment and multifactorial intervention on physical performance among older people. Methods: In a 3-year geriatric development project with an experimental design, 668 participants aged 75–98 were assigned to intervention (n=348) or control (n=320) groups. The intervention group received comprehensive geriatric assessment with an individually targeted intervention for 2 years. The outcome measures—performance in the Timed Up-and-Go (TUG), 10-meter walking and Berg Balance Scale tests 2 were gathered annually during the intervention and the 1-year follow-up after it. Results: With linear mixed models, over the 2-year i…
Associations of long-term exposure to air pollution and road traffic noise with cognitive function : an analysis of effect measure modification
2017
Background: Adverse effects of traffic-related air pollution (AP) and noise on cognitive functions have been proposed, but little is known about their interactions and the combined effect of co-exposure. Methods: Cognitive assessment was completed by 4086 participants of the population-based Heinz Nixdorf Recall cohort study using five neuropsychological subtests and an additively calculated global cognitive score (GCS). We assessed long-term residential concentrations for size-fractioned particulate matter (PM) and nitrogen oxides with land use regression. Road traffic noise (weighted 24-h (LDEN) and night-time (LNIGHT) means) was assessed according to the EU directive 2002/49/EC. Linear r…
Importance of Residual Renal Function in Continuous Ambulatory Peritoneal Dialysis: Its Influence on Different Parameters of Renal Replacement Treatm…
1999
<i>Objective:</i> To study the influence of residual renal function (RRF) on different parameters of the renal substitutive treatment offered by peritoneal dialysis. <i>Methods:</i> We analyzed the impact of RRF on dialysis dose, nutrition parameters, anemia and phosphocalcic metabolism in 37 patients with end-stage renal disease (ESRD) treated by continuous ambulatory peritoneal dialysis (CAPD). Analytical controls were done every 6 months after an initial assessment at the end of the first month of treatment. Multiple lineal regression models were used as the statistical method to analyze the influence of RRF on different theoretically dependent factors. RRF was ca…
Predicting antitrichomonal activity: A computational screening using atom-based bilinear indices and experimental proofs
2006
Existing Trichomonas vaginalis therapies are out of reach for most trichomoniasis people in developing countries and, where available, they are limited by their toxicity (mainly in pregnant women) and their cost. New antitrichomonal agents are needed to combat emerging metronidazole-resistant trichomoniasis and reduce the side effects associated with currently available drugs. Toward this end, atom-based bilinear indices, a new TOMOCOMD-CARDD molecular descriptor, and linear discriminant analysis (LDA) were used to discover novel, potent, and non-toxic lead trichomonacidal chemicals. Two discriminant functions were obtained with the use of non-stochastic and stochastic atom-type bilinear in…
A structured filter for Markovian switching systems
2014
In this work, a new methodology for the structuring of multiple model estimation schemas is developed. The proposed filter is applied to the estimation and detection of active mode in dynamic systems. The discrete-time Markovian switching systems represented by several linear models, associated with a particular operating mode, are studied. Therefore, the main idea of this work is the subdivision of the models set to some subsets in order to improve the detection and estimation performances. Each subset is associated with sub-estimators based on models of the subset. In order to compute the global estimate and subset probabilities, a global estimator is proposed. Theoretical developments ba…
Variables related to the informal caregivers' burden of dependent senior citizens in Spain
2009
The study aims at analyzing the psychosocial variables associated with the informal caregivers" burden of dependent older people. A sample of 296 dependent people and their informal caregivers (n= 153) was randomly selected among users and non-users of the Spanish public In-Home Help Service (HHS) in an autonomous Spanish region (Comunidad Valenciana). Diverse variables in reference to the care context and the caregiver as well as the care recipient show major associations with the burden: those associated to disease and the social situation of the dependent person, the greater frequency and intensity of care, and the low frequency in which the caregiver receives help from others. The obtai…
Event-based criteria in GT-STAF information indices: theory, exploratory diversity analysis and QSPR applications
2012
Versatile event-based approaches for the definition of novel information theory-based indices (IFIs) are presented. An event in this context is the criterion followed in the "discovery" of molecular substructures, which in turn serve as basis for the construction of the generalized incidence and relations frequency matrices, Q and F, respectively. From the resultant F, Shannon's, mutual, conditional and joint entropy-based IFIs are computed. In previous reports, an event named connected subgraphs was presented. The present study is an extension of this notion, in which we introduce other events, namely: terminal paths, vertex path incidence, quantum subgraphs, walks of length k, Sach's subg…
A Critical Review of Statistical Methods for Twin Studies Relating Exposure to Early Life Health Conditions
2021
International audience; When investigating disease etiology, twin data provide a unique opportunity to control for confounding and disentangling the role of the human genome and exposome. However, using appropriate statistical methods is fundamental for exploiting such potential. We aimed to critically review the statistical approaches used in twin studies relating exposure to early life health conditions. We searched PubMed, Scopus, Web of Science, and Embase (2011–2021). We identified 32 studies and nine classes of methods. Five were conditional approaches (within-pair analyses): additive-common-erratic (ACE) models (11 studies), generalized linear mixed models (GLMMs, five studies), gene…