2,658 research outputs found

    Perfil del acoso escolar en institutos de enseñanza secundaria de zonas rurales y urbanas en Andalucía

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    Bullying is a social phenomenon which occurs in all schools and environment. It occurs in peer groups intentinonally and repeatedly with an abuse of authority. It lasts along the time, and it disturbs the emotional and social balance of the victim, and getting to produce impairment of his/her personality leading to an inhibition of the subject to social relations. In bullyng, there are different ways and modes. According to the way of bullying, it can be physical, orally, social and psychological and ciberbullying. According to the modes, it can be direc or indirect.El bullying o acoso escolar, es un fenómeno de carácter social que se manifiesta en las escuelas y su entorno, se produce en los grupos de iguales de forma intencional y reiterada con abuso de superioridad, es persistente en el tiempo y perturba el equilibrio emocional y social de la víctima, llegando a producir menoscabo de su personalidad que desemboca en una inhibición del sujeto a las relaciones sociales. En el acoso escolar se puede diferenciar, modos y formas. Según la forma en que se produce se distingue acoso verbal, físico, social, psicológico y ciberbullying; según el modo en que se produce se puede distinguir de modo directo o de modo indirecto

    Impact of Food Assistance Programs on Obesity in Mothers and Children: A Prospective Cohort Study in Peru.

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    Objectives. To assess obesity risk among mothers participating in Community Kitchens and children participating in Glass of Milk (Peru food assistance programs). Methods. We analyzed prospective data from the Young Lives study. The exposure consisted in varying degrees of benefit from any of the programs (no participation in any of the programs, program participation for some months, or program participation nearly every month) at baseline (2006–2007). The outcome was overweight and obesity in mothers and children at follow-up (2009–2010). Results. Prevalence of childhood overweight and obesity was 15.5% and 5.1%, respectively; the corresponding figures for mothers were 40.5% and 14.6%. Children exposed nearly every month to the Glass of Milk program had a 65% lower risk of becoming obese compared with children not participating in the program (relative risk [RR] = 0.35; 95% confidence interval [CI] = 0.18, 0.66). Mothers participating frequently in the Community Kitchens program had almost twice the risk of becoming obese compared with those who did not participate (RR = 1.93; 95% CI = 1.18, 3.15). Conclusions. Participating in food assistance programs in Peru was associated with a lower risk of obesity in children and greater risk of obesity in mothers.Revisión por pare

    Ground States for Diffusion Dominated Free Energies with Logarithmic Interaction

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    Replacing linear diffusion by a degenerate diffusion of porous medium type is known to regularize the classical two-dimensional parabolic-elliptic Keller-Segel model. The implications of nonlinear diffusion are that solutions exist globally and are uniformly bounded in time. We analyse the stationary case showing the existence of a unique, up to translation, global minimizer of the associated free energy. Furthermore, we prove that this global minimizer is a radially decreasing compactly supported continuous density function which is smooth inside its support, and it is characterized as the unique compactly supported stationary state of the evolution model. This unique profile is the clear candidate to describe the long time asymptotics of the diffusion dominated classical Keller-Segel model for general initial data.Comment: 30 pages, 2 figure

    Gorgojos (Coleoptera, Curculionidae) asociados al cultivo del pistacho (Pistacia vera L.) en Castilla – La Mancha

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    This paper presents the results of research carried out in pistachio plantations in the provinces of Ciudad Real, Cuenca and Toledo (Castilla – La Mancha Region), which led to the discovery of eight Curculionidae species from five genera (Brachyderes, Otiorhynchus, Polydrusus, Sitona and Lixus) of two subfamilies (ENTIMINAE and LIXINAE). Brachyderes marginellus, B. pubescens, Polydrusus subglaber, Otiorhynchus cribricollis and Lixus acicularis have been observed feeding on P. vera leaves, and they are recorded for the first time in this host plant. Polydrusus subglaber and Otiorhynchus cribricollis fed intensively in these leaves and further research on these species is recommended as they may represent important pistachio defoliators in the region. Biological and distributional data of these species are given.Se presentan los resultados de diversos muestreos llevados a cabo sobre parcelas cultivadas de pistachero en diferentes localidades de Castilla – La Mancha, en las provincias de Ciudad Real, Cuenca y Toledo. Se han encontrado un total de 8 especies de Curculionidae, de 5 géneros (Brachyderes, Otiorhynchus, Polydrusus, Sitona y Lixus) correspondientes a 2 subfamilias: ENTIMINAE y LIXINAE. Brachyderes marginellus, B. pubescens, Polydrusus subglaber, Otiorhynchus cribricollis y Lixus acicularis se han observado alimentándose de hojas de P. vera y se citan por primera vez sobre esta planta huésped. Polydrusus subglaber y Otiorhynchus cribricollis devoran intensamente sus hojas, por lo que se propone seguir investigando estas dos especies como importantes defoliadores de pistacho en la región. Se aportan datos biológicos y corológicos para las especies encontradas

    Physical education and school bullying: a systematic review

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    Objectives: To evaluate the associations of physical education (PE) with school violence and bullying. Design: Systematic review. Method: Using a systematic search in Medline, PsycINFO, SPORTDiscus, Web of Science, and Scopus, relevant studies with a quantitative and qualitative design were identified that met previously established eligibility criteria. Quality was assessed (bias risk analysis) and data were extracted from a previously elaborated template. Results: The systematic review finally included 16 studies, of which 10 had a quantitative design (n = 12795), 5 a qualitative design (n = 79) and 1 a mixed design (n = 86). The high heterogeneity presented by the measures used in the included studies hindered the comparison of the outcomes and prevented meta-analysis of the data. Although there is insufficient evidence about the positive impact of PE on bullying prevention, the results of this review indicate that some aspects of PE programs could improve students’ skills to cope with these situations. Conclusions: The results of this review suggest the importance of PE in the prevention of bullying. Secondly, it is emphasized that bullying situations have a negative impact on students’ enjoyment of PE, leading to detrimental consequences for their physical and psychological health. Thirdly, the figure of the PE teacher as a key element to prevent and/or encourage bullying was obvious

    A numerical solver for a nonlinear Fokker-Planck equation representation of neuronal network dynamics

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    To describe the collective behavior of large ensembles of neurons in neuronal network, a kinetic theory description was developed in [13, 12], where a macroscopic representation of the network dynamics was directly derived from the microscopic dynamics of individual neurons, which are modeled by conductance-based, linear, integrate-and-fire point neurons. A diffusion approximation then led to a nonlinear Fokker-Planck equation for the probability density function of neuronal membrane potentials and synaptic conductances. In this work, we propose a deterministic numerical scheme for a Fokker-Planck model of an excitatory-only network. Our numerical solver allows us to obtain the time evolution of probability distribution functions, and thus, the evolution of all possible macroscopic quantities that are given by suitable moments of the probability density function. We show that this deterministic scheme is capable of capturing the bistability of stationary states observed in Monte Carlo simulations. Moreover, the transient behavior of the firing rates computed from the Fokker-Planck equation is analyzed in this bistable situation, where a bifurcation scenario, of asynchronous convergence towards stationary states, periodic synchronous solutions or damped oscillatory convergence towards stationary states, can be uncovered by increasing the strength of the excitatory coupling. Finally, the computation of moments of the probability distribution allows us to validate the applicability of a moment closure assumption used in [13] to further simplify the kinetic theory

    Analysis of nonlinear noisy integrate & fire neuron models: blow-up and steady states

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    Nonlinear Noisy Leaky Integrate and Fire (NNLIF) models for neurons networks can be written as Fokker-Planck-Kolmogorov equations on the probability density of neurons, the main parameters in the model being the connectivity of the network and the noise. We analyse several aspects of the NNLIF model: the number of steady states, a priori estimates, blow-up issues and convergence toward equilibrium in the linear case. In particular, for excitatory networks, blow-up always occurs for initial data concentrated close to the firing potential. These results show how critical is the balance between noise and excitatory/inhibitory interactions to the connectivity parameter

    Skinfold thickness and the incidence of type 2 diabetes mellitus and hypertension: an analysis of the PERU MIGRANT study.

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    OBJECTIVE: To determine the association between excess body fat, assessed by skinfold thickness, and the incidence of type 2 diabetes mellitus (T2DM) and hypertension (HT). DESIGN: Data from the ongoing PERU MIGRANT Study were analysed. The outcomes were T2DM and HT, and the exposure was skinfold thickness measured in bicipital, tricipital, subscapular and suprailiac areas. The Durnin-Womersley formula and SIRI equation were used for body fat percentage estimation. Risk ratios and population attributable fractions (PAF) were calculated using Poisson regression. SETTING: Rural (Ayacucho) and urban shantytown district (San Juan de Miraflores, Lima) in Peru. PARTICIPANTS: Adults (n 988) aged ≥30 years (rural, rural-to-urban migrants, urban) completed the baseline study. A total of 785 and 690 were included in T2DM and HT incidence analysis, respectively. RESULTS: At baseline, age mean was 48·0 (sd 12·0) years and 47 % were males. For T2DM, in 7·6 (sd 1·3) years, sixty-one new cases were identified, overall incidence of 1·0 (95 % CI 0·8, 1·3) per 100 person-years. Bicipital and subscapular skinfolds were associated with 2·8-fold and 6·4-fold risk of developing T2DM. On the other hand, in 6·5 (sd 2·5) years, overall incidence of HT was 2·6 (95 % CI 2·2, 3·1) per 100 person-years. Subscapular and overall fat obesity were associated with 2·4- and 2·9-fold risk for developing HT. The PAF for subscapular skinfold was 73·6 and 39·2 % for T2DM and HT, respectively. CONCLUSIONS: We found a strong association between subscapular skinfold thickness and developing T2DM and HT. Skinfold assessment can be a laboratory-free strategy to identify high-risk HT and T2DM cases

    Contractions in the 2-wasserstein lenght space and thermalization of granular media

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    An algebraic decay rate is derived which bounds the time required for velocities to equilibrate in a spatially homogeneous flowthrough model representing the continuum limit of a gas of particles interacting through slightly inelastic collisions. This rate is obtained by reformulating the dynamical problem as the gradient flow of a convex energy on an infinite-dimensional manifold. An abstract theory is developed for gradient flows in length spaces, which shows how degenerate convexity (or even non-convexity) - if uniformly controlled - will quantify contractivity (limit expansivity) of the flow
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