Search results for "Group"
showing 10 items of 19225 documents
Projecte d'investigació-acció: Violència escolar i integració social
2006
En aquest treball es presenta el Projecte d'Investigació-Acció realitzat pel grup Lisis de la Universitat de València. Des del model ecològic, l'interès està a analitzar i prevenir la conducta violenta entre iguals a l'escola. Per a això s'ha aplicat en una mostra de 1319 adolescents d'edats compreses entre els 11 i els 16 anys una bateria d'instruments. En aquest article s'exposa, a tall d'exemple, un dels models d'equacions estructurals calculats en aquesta investigació. En concret s'analitza l'efecte directe i l'indirecte del clima familiar en la conducta violenta entre iguals i en el context escolar.
Postmodernity, insecurity and job loss Focus on the unemployed's suffering
2017
International audience; Objectives Recent research shows clear correlations between the subjective perception of job's insecurity and physical, mental and relational health. This article highlights the difficulties of workers , and particularly the impact of uncertainty and job loss on their self-esteem and psycho-physical well-being. The work presents and contextualizes the perception of job insecurity as an effect of postmodern society.Methods The research involved 60 subjects that have lost the jobs and received a 3 month intervention of active policies organized in groups focusing on empowerment and employability. At two times before and after group participants filled in Rosenberg Self…
Comparative Cytogenetic Analysis of Three Stylommatophoran Slugs (Mollusca, Pulmonata)
2009
system is still controversial because phylogeny and systematic relationships at the family level are poorly understood. Besides morphological studies, ribosomal RNA genes and the H3/H4 histone gene cluster (Ambruster et al., 2005; Wade et al., 2006) have also been used to resolve the relationships within this order. Recently, by comparison of primary sequence of mitochondrial and nuclear genes, Grande et al. (2004) resolved the Stylommatophora as the early split monophyletic sister group of all the other gastropod taxa. Available data on the cytogenetics of Stylommatophora are extremely poor (reviewed by Patterson, 1969, and Thiriot-Quievreux, 2003) and mostly concern the haploid (n) and/ o…
Singletons on AdSn
2000
We define the singletons for the invariance group \( {\overline S _n} = {\overline {SO} _0}\left( {2,n - 1} \right) \)) of the AdS n space-time. We write down some of their important properties and characterizations. It is found that the tensor product of singletons of spin 0 or 1/2 decomposes into representations that are a kind of massless representations of S n . Other kinds of massless representations, related to singletons, are also studied and a comparison is made. Various Gupta-Bleuler triplets are constructed for singletons and for massless representations.
Variation in the Senecio aethnensis group (Asteraceae) along an altitudinal gradient
2003
ABSTRACT The variability of the Senecio aethnensis group was investigated through morphometric analyses of seven populations along an altitudinal transect on Mt. Etna (E Sicily). The data obtained show a separation into two groups, one including the populations of the upper and middle belts, at and above 1700 m, the other including the populations from lower altitudes. In the first group a clinal morphological variation in several reproductive and vegetative characters was observed in relation to altitude. The analysis of leaf characters in progeny cultivated under uniform conditions confirmed the differentiation into the two groups, which are to be treated as separate species, i.e. S. aeth…
Synthesis of hyperbranched poly(tert-butyl acrylate) by self-condensing atom transfer radical polymerization of a macroinimer
2000
Using 2-hydroxyethyl α-bromoisobuty-rate as initiator, atom transfer radical polymerization (ATRP) of tert-butyl acrylate leads to poly(tert-butyl acrylate) (PtBA) with a hydroxyl group at one and a bromine atom at the other end. Esterification of the hydroxyl group of these heterotelechelic polymers with acryloyl chloride yields PtBA (M n = 3060) with a polymerizable double bond at one end and a bromine atom at the other end which can act as an initiator in ATRP (macroinimer). Self-condensing ATRP of such a macroinimer leads to hyperbranched or highly branched PtBA. The polymer was characterized by GPC viscosity measurements. Even at M w = 78800, a rather low polydispersity index of M w M …
Three-page encoding and complexity theory for spatial graphs
2004
We construct a series of finitely presented semigroups. The centers of these semigroups encode uniquely up to rigid ambient isotopy in 3-space all non-oriented spatial graphs. This encoding is obtained by using three-page embeddings of graphs into the product of the line with the cone on three points. By exploiting three-page embeddings we introduce the notion of the three-page complexity for spatial graphs. This complexity satisfies the properties of finiteness and additivity under natural operations.
On the empirical spectral distribution for certain models related to sample covariance matrices with different correlations
2021
Given [Formula: see text], we study two classes of large random matrices of the form [Formula: see text] where for every [Formula: see text], [Formula: see text] are iid copies of a random variable [Formula: see text], [Formula: see text], [Formula: see text] are two (not necessarily independent) sets of independent random vectors having different covariance matrices and generating well concentrated bilinear forms. We consider two main asymptotic regimes as [Formula: see text]: a standard one, where [Formula: see text], and a slightly modified one, where [Formula: see text] and [Formula: see text] while [Formula: see text] for some [Formula: see text]. Assuming that vectors [Formula: see t…
The effect of macromolecular architecture of ethylene copolymers with multi-alkenylsilsesquioxane on morphological, rheological and dynamic mechanica…
2021
Abstract The influence of the degree and the way of incorporation of multi-alkenylsilsesquioxane into the polymer chain on morphological, rheological and dynamic mechanical parameters were determined. It was found that POSS incorporated into the polymer chain was located outside the crystalline structure of lamella in amorphous phase. The incorporation of POSS-6-2 as a pendant group resulted in significant increase of separation of macromolecules. The key factor in rheological and dynamic mechanical behavior of copolymers turned out to be the way of POSS incorporation into the polymer chain. The incorporation of POSS into the polymer chain as a pendant group resulted in decreased relaxation…
The effects of the Nordic hamstring exercise on sprint performance and eccentric knee flexor strength: A systematic review and meta-analysis of inter…
2021
Objectives: The primary aim of this study was to investigate the effects of the Nordic hamstring exercise (NHE) on sprint performance (i.e., 5, 10 and 20 m) and explore associations between study characteristics and sprint outcomes in team sport players. Secondary aims were to (1) investigate the effects of the NHE on eccentric strength of the knee flexors (ESKF) with categorical subgroup analysis to determine differences between recreationally, well-trained individuals and young athletes, (2) determine the relation between ESKF and sprint performance in team sport players, and (3) explore the effect of study characteristics (i.e., weekly volume, time duration and body mass) on ESKF.Methods…