Search results for "Multivariate Analysi"

Application of multivariate T-pattern analysis in the study of social interaction in rats

2015

ABSTRACT NON PREVISTO DALLA PUBBLICAZIONE

Prognostic significance of p16INK4a alterations and 9p21 loss of heterozigosity in locally advanced laryngeal squamous cell carcinoma

2002

The p16INK4a gene, localized within chromosome 9p21, has been identified as a cyclin-dependent kinase inhibitor and may negatively regulate the cell cycle acting as a tumor suppressor. Genetic alterations involving the 9p21 region are common in human cancers. A consecutive series of 64 untreated patients (median of follow up 53 months) undergoing surgical resection for locally advanced laryngeal squamous-cell carcinomas (LSCCs) has been studied prospectively. Our purpose was to investigate p16 alterations (9p21 allelic loss, hypermethylation and point mutations) and their possible association with clinico-pathological data and flow cytometric variables (DNA-ploidy and S-phase fraction (SPF)…

The silver collection of San Gennaro treasure (Neaples): A multivariate statistic approach applied to X-ray fluorescence data

2021

Abstract In this work we report an X-ray fluorescence spectroscopy (XRF) study combined with a multivariate approach allowing to detect compositional differences and similarities among the alloys used in realization of silver collection of San Gennaro items collection. The San Gennaro treasure in Naples (Italy) represents, in fact, one of the most important silver collections in the world. The classification of the collection items is very complex, not only for the large number of objects, but also in consideration that between 1600 and 1700, in Naples, more than 350 laboratories were active, most of them specialized in specific art of work. As a consequence, a given collection object could…

P0792 : Baseline factors associated with increased SVR rates in 123 treatment-naïve chronic HCV genotype 1 patients treated with a shortened 12-week …

2015

Effectiveness of a mobile app intervention to prevent dating violence in residential child care

2020

ABSTRACT This study focuses on the effectiveness of an app-based, monitored intervention using the Liad@s app in a residential youth-care setting. The aim of this intervention is to reduce maladaptive beliefs and attitudes linked to dating violence: distortions or myths about romantic love and hostile and benevolent dimensions of sexism. A quasi-experimental pre-post study with a control group was carried out. Participants were 71 adolescents from 9 group homes in Valencia (Spain). The outcomes measures were hostile and benevolent sexism (Ambivalent Sexism Inventory - ASI), ambivalence and prejudice towards men (Ambivalence toward Men Inventory - AMI), and myths about romantic love. The res…

Curative therapies are superior to standard of care (transarterial chemoembolization) for intermediate stage hepatocellular carcinoma.

2017

Background and aims the Barcelona Clinic Liver Cancer intermediate stage (BCLC-B) of hepatocellular carcinoma (HCC) includes extremely heterogeneous patients in terms of tumor burden and liver function. Transarterial-chemoembolization (TACE) is the first-line treatment for these patients although it may be risky/useless for someone, while others could undergo curative treatments. This study assesses the treatment type performed in a large cohort of BCLC-B patients and its outcome. Methods retrospective analysis of 485 consecutive BCLC-B patients from the ITA.LI.CA database diagnosed with naive HCC after 1999. Patients were stratified by treatment. Results 29 patients (6%) were lost to follo…

Effects of morphometric descriptor changes on statistical classification and morphospaces

2004

Ten morphometric descriptors (five pairs of form and shape parameters) are used to describe the complex morphology of the first lower molar of two morphologically similar species, Microtus arvalis and M. agrestis. These descriptors are derived either from linear measurements or from outline analysis. The effects of these different descriptors on classical analysis as used in biology or palaeobiology are explored. First, the reliability of results in statistical classification is assessed. All of the descriptors discriminate well between the two species. The initial morphometric scheme (linear or outline) does not induce marked differences in statistical classification and the major discrepa…

Automatic variable selection for exposure-driven propensity score matching with unmeasured confounders.

2020

Multivariable model building for propensity score modeling approaches is challenging. A common propensity score approach is exposure-driven propensity score matching, where the best model selection strategy is still unclear. In particular, the situation may require variable selection, while it is still unclear if variables included in the propensity score should be associated with the exposure and the outcome, with either the exposure or the outcome, with at least the exposure or with at least the outcome. Unmeasured confounders, complex correlation structures, and non-normal covariate distributions further complicate matters. We consider the performance of different modeling strategies in …

The asymptotic covariance matrix of the Oja median

2003

The Oja median, based on a sample of multivariate data, is an affine equivariant estimate of the centre of the distribution. It reduces to the sample median in one dimension and has several nice robustness and efficiency properties. We develop different representations of its asymptotic variance and discuss ways to estimate this quantity. We consider symmetric multivariate models and also the more narrow elliptical models. A small simulation study is included to compare finite sample results to the asymptotic formulas.

Estimating the decomposition of predictive information in multivariate systems

2015

In the study of complex systems from observed multivariate time series, insight into the evolution of one system may be under investigation, which can be explained by the information storage of the system and the information transfer from other interacting systems. We present a framework for the model-free estimation of information storage and information transfer computed as the terms composing the predictive information about the target of a multivariate dynamical process. The approach tackles the curse of dimensionality employing a nonuniform embedding scheme that selects progressively, among the past components of the multivariate process, only those that contribute most, in terms of co…