Search results for "Nonparametric"
showing 10 items of 427 documents
Perinatal exposure to 5-methoxytryptamine, behavioural-stress reactivity and functional response of 5-HT1A receptors in the adolescent rat.
2008
Abstract Serotonin is involved in a wide range of physiological and patho-physiological mechanisms. In particular, 5-HT1A receptors are proposed to mediate stress-adaptation. The aim of this research was to investigate in adolescent rats: first, the consequences of perinatal exposure to 5-metoxytryptamine (5MT), a 5-HT1/5-HT2 serotonergic agonist, on behavioural-stress reactivity in elevated plus maze, open field and forced swim tests; secondly, whether the behavioural effects induced by perinatal exposure to 5MT on open field and forced swim tests were affected by the selective 5-HT1A receptor agonist LY 228729, a compound able to elicit a characteristic set of motor behaviours on these ex…
An Application of Hybrid Models in Credit Scoring
2000
The predictive capability of parametric and non-parametric models in solving problems related to financial classification has been widely proved in empirical research carried out in the financial field, particulary in problems like bond rating, bankruptcy prediction and credit scoring. However, recently, it has been shown that a combination of different models generally reduces the prediction error, so that the best alternative to consider may not be a specific model but a combination of them. In this paper, we study hybrid systems based on the aggregation of individual (parametric and nonparametric) models. Our hybrids are built by using both parametric and non parametric models as the sys…
Parametric and nonparametric A-Laplace problems: Existence of solutions and asymptotic analysis
2021
We give sufficient conditions for the existence of weak solutions to quasilinear elliptic Dirichlet problem driven by the A-Laplace operator in a bounded domain Ω. The techniques, based on a variant of the symmetric mountain pass theorem, exploit variational methods. We also provide information about the asymptotic behavior of the solutions as a suitable parameter goes to 0 + . In this case, we point out the existence of a blow-up phenomenon. The analysis developed in this paper extends and complements various qualitative and asymptotic properties for some cases described by homogeneous differential operators.
Analysis of the authors’ rights collection frontier using PCA-MDEA: an application to the Valencia region
2002
The aim of this paper is to estimate the authors’ rights collection frontier within the collection zones into which the Valencia Region (Spain) has been divided. To be more exact, a nonparametric frontier technique (Modified Data Envelopment Analysis, MDEA) and the Principal Components Analysis (PCA) are jointly employed to map out an initial approach to the potential authors’ rights collection within this region (as divided into collection zones). The analysis has been carried out both jointly and by majority sectors (performing, musical, and audio-visual arts). Publicaciones Econcult: Área de Investigación en Economía de la Cultura y Turismo. Universitat de València
Bone status in adolescents with type 1 diabetes
2010
Aims The aim of the study was to investigate the potential negative impact of type 1 diabetes on bone status of adolescents. Bone status in adolescents with type 1 diabetes was assessed by means of quantitative ultrasound (QUS) and the influence of metabolic control and other diseaserelated and growth variables was analysed. Methods Group I consisted of 99 pubertal (Tanner ≥2) adolescents (49 female), aged 14.3±2.5 years, diabetes duration 4.6±2.3 years. Controls (group II) were 297 children, matched by sex and age, from a healthy population. The influence of glycated haemoglobin (current: HbA1cD; last year’s mean: HbA1cY; whole duration mean: HbA1cT), diabetes duration, percentage of life …
Five-year results following treatment of intrabony defects with enamel matrix proteins and guided tissue regeneration
2004
Treatment with enamel matrix proteins (EMD) or guided tissue regeneration (GTR) has been shown to enhance periodontal regeneration. However, until now there are limited data on the long-term results following these treatment modalities.The aim of the present clinical study was to present the 5-year results following treatment of intrabony defects with EMD, GTR, combination of EMD and GTR, and open flap debridement (OFD).Forty-two patients, each of whom displayed one intrabony defect of a probing depth of at least 6 mm, were randomly treated with one of the four treatment modalities. The following parameters were evaluated prior to surgery, at 1 year and at 5 years after: plaque index, gingi…
Searching for the right timing of surgical delay: angiogenesis, vascular endothelial growth factor and perfusion changes in a skin-flap model.
2009
Summary Background The angiogenic potential of vascular endothelial growth factor (VEGF) and its oxygen pressure-dependent regulation suggest a strong connection between this growth factor and the ‘delay phenomenon'. In this study we focused on the chronological changes in VEGF concentration and flap perfusion in order to optimise the duration of surgical delay. Methods The VEGF concentration in skin and underlying muscle was measured in oversized, random-pattern flaps on 38 male Sprague-Dawley rats after 3, 5 or 7 days of surgical delay. Additionally, flaps were raised 5 or 7 days past preconditioning. The effect on flap perfusion was measured using indocyanine green fluoroscopy and the si…
Morphological parameters as predictors of successful correction of Class III malocclusion
2001
The aim of the study was to assess pre-treatment cephalometric parameters and measurements of the size of the apical bases as predictors of successful orthodontic correction of Class III malocclusions. Pre- and post-treatment lateral cephalograms and study models of 80 completed Class III subjects were examined to obtain 23 cephalometric parameters taken mainly from the analyses of McNamara and Schwarz, and to measure the size of the apical bases. Success of occlusal correction was evaluated as the percentage change of peer assessment rating score during treatment, which was used as the dependent variable in multivariate statistical analyses testing the predictive value of the parameters as…
A blended-learning programme regarding professional ethics in physiotherapy students.
2018
Background: In the university context, assessing students’ attitude, knowledge and opinions when applying an innovative methodological approach to teach professional ethics becomes fundamental to know if the used approach is enough motivating for students. Research objective: To assess the effect of a blended-learning model, based on professional ethics and related to clinical practices, on physiotherapy students’ attitude, knowledge and opinions towards learning professional ethics. Research design and participants: A simple-blind clinical trial was performed (NLM identifier NCT03241693) (control group, n = 64; experimental group, n = 65). Both groups followed clinical practices for 8 mont…
Thalamic Network Oscillations Synchronize Ontogenetic Columns in the Newborn Rat Barrel Cortex
2013
Neocortical areas are organized in columns, which form the basic structural and functional modules of intracortical information processing. Using voltage-sensitive dye imaging and simultaneous multi-channel extracellular recordings in the barrel cortex of newborn rats in vivo, we found that spontaneously occurring and whisker stimulation-induced gamma bursts followed by longer lasting spindle bursts were topographically organized in functional cortical columns already at the day of birth. Gamma bursts synchronized a cortical network of 300-400 µm in diameter and were coherent with gamma activity recorded simultaneously in the thalamic ventral posterior medial (VPM) nucleus. Cortical gamma b…