1,495 research outputs found

    Educación bilingüe en EE.UU. Estudio de casos de una escuela primaria

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    Los Estados Unidos de América son por su historia una nación lingüística y culturalmente diversa desde sus orígenes, lo que ha obligado a la administración a atender a los grupos minoritarios y a dar respuestas adecuadas a sus necesidades educativas. Este trabajo arranca con un recorrido por lo que ha supuesto la política estadounidense en materia de instrucción lingüística a los hijos de los inmigrantes. Exponemos las respuestas de educación bilingüe que se han ido dando a las minorías. Desde una investigación que responde al diseño de estudio de casos hemos analizado una escuela bilingüe del condado de Los Ángeles en California. La escuela responde al modelo Two-Way Immersion/Dual Language Immersion. Este modelo busca integrar a las minorías lingüísticas con la mayoría dominante y conseguir que siguiendo instrucción en dos lenguas ambos grupos sean bilingües y desarrollen actitudes de respeto hacia otras culturas. El modelo TWI/DLI puede ser de ayuda en la implantación de las líneas de educación bilingüe/plurilingüe en algunas comunidades autónomas que comienzan su andadura en este ámbito

    Stable propagation of pulsed beams in Kerr focusing media with modulated dispersion

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    We propose the modulation of dispersion to prevent collapse of planar pulsed beams which propagate in Kerr-type self-focusing optical media. As a result, we find a new type of two-dimensional spatio-temporal solitons stabilized by dispersion management. We have studied the existence and properties of these solitary waves both analytically and numerically. We show that the adequate choice of the modulation parameters optimizes the stabilization of the pulse.Comment: 3 pages, 3 figures, submitted to Optics Letter

    Controllable soliton emission from a Bose-Einstein condensate

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    We demonstrate, through numerical simulations, the controllable emission of matter-wave bursts from a Bose-Einstein Condensate in a shallow optical dipole trap. The process is triggered by spatial variations of the scattering length along the trapping axis. In our approach, the outcoupling mechanism are atom-atom interactions and thus, the trap remains unaltered. Once emitted, the matter wave forms a robust soliton. We calculate analytically the parameters for the experimental implementation of this atomic soliton machine gun.Comment: 4 pages, 5 figure

    Optimized routing for people with permanent or temporary mobility disability: a case study in Viana do Castelo

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    Nowadays, it is already common to have apps to assist citizens in their mobility within a city. However, apps are usually designed for the general citizen and do not include the specificity of people with reduced mobility, temporarily or permanently, such as visually impaired people, autistic people, people in wheelchairs, among others segments. This paper illustrates a case study carried out in the city of Viana do Castelo, in Portugal, where the streets of the historic center of the city were classified in a Geographic Information System (GIS) by the City Council together with the institutions that represent each one of the considered segments. Based on this classification, the Viana+Acessivel app was developed, which is about to be made available free of charge to all citizens, and which recommends to each user the optimum route from a source to a destination, taking into account his segment. For example, visually impaired people should avoid streets where emergency vehicles can circulate and autistic people should preferably avoid streets with loud noises, among other conditions. The A -Star Algorithm and Dijkstra Algorithm were used in the app to identify the optimum route. A comparative study was made concluding that both strategies identify the optimum route and A -Star method obtains the optimum solution in a faster time. An evaluation of the app was also made in terms of its effectiveness and usability.info:eu-repo/semantics/publishedVersio

    Sistemas agroflorestais: conciliando a conservação do ambiente e a geração de renda nas propriedades rurais.

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    Durante o processo de consolidação dos SAFs em Roraima houve a necessidade de obter informações técnicas sobre as diferentes etapas de implantação e manejo dos modelos agroflorestais. Os trabalhos de pesquisa foram conduzidos no campo experimental Confiança, pertencente à Embrapa Roraima. O modelo agrossilvicultural foi composto por culturas anuais (arroz, milho, soja, feijão caupi (Vigna sp.) e mandioca), bananeira, ingá-de-metro, gliricídia (Gliricidia sepium), cupuaçuzeiro, pupunheira, castanha-do-Brasil e cupiúba (Goupia glabra). A avaliação financeira apresentou resultados onde a proporção entre as receitas e os custos em cada ano do desenvolvimento do projeto, tornou evidente que as receitas superaram os custos a partir do oitavo ano, com uma tendência positiva até o último ano de avaliação do projeto. Houve maior demanda de mão-de-obra no início da implantação do projeto com uma gradativa redução desta necessidade à medida que o projeto atingiu sua estabilidade. O ponto mais importante a ser observado nesta tendência é a quantidade de diárias necessárias em cada fase de avaliação do projeto (implantação, consolidação, estabilidade e finalização). Os principais indicadores financeiros, avaliados durante o período de 20 anos, com uma taxa de juros de 4%, foram: RB/C= 3,7; VPL=R$ 83.276,50; TIR= 35,40%, com tempo de retorno do investimento de 5,4 anos. Tais resultados indicam a viabilidade financeira do modelo agroflorestal avaliado

    Testosterone and Cholesterol Vasodilation of Rat Aorta Involves L-Type Calcium Channel Inhibition

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    Testosterone has rapid nongenomic vasodilator effects which could be involved in protective cardiovascular actions. Several authors suggested specific mechanisms to explain this effect, but this matter was not clarified yet. We studied the actions of testosterone and cholesterol on endothelium-denuded rat aorta and their effects on the L-type Ca2+ current (ICa,L) and potassium current (IK). Testosterone (1–100 μM) totally relaxed, in a rapid and concentration-dependent way, the aortic rings contracted by KCl or by (−)-Bay K8644 (BAY). Cholesterol also fully relaxed the contractions induced by KCl. None of the potassium channel antagonists tested (glibenclamide, tetraethylammonium and 4-aminopyridine) modified significantly the relaxant effect of testosterone. The antagonist of classic testosterone receptors, flutamide, did not modify the vasorelaxant effect of testosterone. Furthermore, testosterone and cholesterol inhibited either basal and BAY-stimulated ICa,L in A7r5 cells and they have no effects on IK. In summary, our results demonstrate that cholesterol and testosterone relax rat aorta by inhibiting LTCC. This effect of testosterone is not mediated by the classic hormone receptor or by potassium channel activation. These results suggest that the vasodilator mechanism of cholesterol and testosterone is the same

    Effectiveness of clinical assessment in Spanish forensic practice: detecting malingered psychosocial sequelae in victims of intimate partner violence

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    Background and Objectives: According to Spanish legislation, the psychological harm suffered by the victim of a criminal act is determined by assessing its impact on the victim's mental state. Usually, the victim's pain and suffering is estimated by administering clinical scales. The aim of the present study was to explore the effectiveness of psychopathological assessment using commonly used scales in clinical practice and whose results are presented as legal evidence in a forensic context in order to detect malingered psychological sequelae (anxiety, depression and low self-esteem) in victims of intimate partner violence in forensic contexts. Methods: In the present study three scales based in a clinical setting and regularly used in a forensic context were administered (BDI, STAI and Rosenberg) to assess malingering of symptoms. The sample comprised 66 women: 36 students, and 30 real victims. The non-clinical sample was evaluated twice: the first time they gave sincere responses, and the second time they were instructed to answer as if they were victims. The real victims underwent testing in a forensic context. Results and Conclusions: The results of our research show that, even without previous knowledge of the scales, people can distort the test results by malingering symptoms that are normally accepted as sequelae of intimate partner violence, especially depression and low self-esteem; however, the results for anxiety, were less homogeneous. Although these tests are used extensively in clinical psychology, our study confirms that, just by themselves, they are not a reliable source of information in a forensic context

    Drammaturgia musicale e altri studi

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    Numero monografico che raccoglie contributi di neolaureati e giovani studiosi dedicati all'attivit\ue0 musicale a Palermo tra Cinque e Settecento, con notizie inedite ricavate da fonti archivistiche

    Evaluación de la función adrenal en perros

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    En 30 perros sanos, hemos estudiado los niveles de cortisol plasmático antes y después de la administración de hormona adrenocórticotropa (ACTH sintético, vía i.m.) y de dexametasona (dosis de 0,01 y 0,02 mg/Kg p.v., vía i.v.), Las pruebas se iniciaron siempre antes de las 10 horas de la mañana y las determinaciones de cortisol plasmático se evaluaron mediante técnicas de RIA. En nuestras condiciones de trabajo, hemos encontrado unos niveles basales de cortisol cuyo rango va de 0,17 a 7,95 ug/ dl. Se ha observado que, en perros sin sintomatología adrenal y con perfiles hematológicos y bioquímicos normales, la prueba de estimulación con ACTH exógeno, a las dos horas de su administración, es capaz de discriminar como animales sanos el 76,7% de los individuos (23 animales), dando falsos resultados positivos en el 10% (3 animales) y una estimulación baja en el U)% (4 animales). La prueba con dexametasona (0,01 mg/Kg p.v.), a las 8 horas de su aplicación, sólo es capaz de ejercer efecto inhibitorio en el 40% de los casos (12 individuos); pero cuando se incrementa la dosis al doble (dexametasona 0,02 mg/Kg p.v.) se 49 obtienen los mejores resultados de toda la experiencia porque se produce el efecto supresor esperado en el 96,7% de los individuos (29 animales).Thirty healty dogs uiere evaluated for plasma cortisol values before and after adrenocorticotrophic hormone (ACm, administered i.m.) and low dose dexamethasone (0.01 and 0.02 mglKgp.v. administered i.u.). The assays started always before 10 hour A.M.} and cortisol plasma concentrations were determined by RIA. In our laboratory we have obserued the normal baseline morning cortisol concentration was between 0.17 and 7.95 ¡..tgldl. ACTH-estimulation test wasfound abnormal bypereponse in 10% (J animals), anormallow stimulation in 11.1% (a dogs) and a expected byperreponse in 76.7% (23) ofthe normal dogs.Dexamethasone-screening test (0.01 mg/Kgp.v.) bring us supressed effect in 40% (12 animals). But wefound the best reliable results when screening test was applied with 0.02 mg/Kgp.v. dexamethasone dose. the suppressed especting effect wasfound in 06. 7% (29 dogs)
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