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La educación bilingüe: ¿Una respuesta al Aragón trilingüe?

  • Huguet, Àngel
  • Chireac, Silvia María
  • Janés i Carulla, Judit
  • Lapresta Rey, Cecilio
  • Navarro Sierra, José Luis
  • Querol Coronado, Mònica
  • Sansó Galiay, Clara
Frente al progresivo reconocimiento de los derechos de las diferentes minorías lingüísticas del Estado español, en el caso de Aragón no ha sido hasta recientemente que el debate sobre el papel de las lenguas minoritarias ha alcanzado cierta notoriedad. Más concretamente, la reforma del Estatuto de Autonomía aprobada en 2007 establece el mandato de desarrollar una Ley de Cortes que determine las zonas de uso predominante de las lenguas y modalidades propias de la región, así como otros aspectos relativos a su recuperación, promoción o enseñanza. En este contexto, el artículo presenta una taxonomía de los modelos de educación bilingüe y describe los resultados de diversos estudios centrados en el análisis de las actitudes lingüísticas manifestadas por los ciudadanos aragoneses. A partir de ello, se plantea una propuesta de educación bilingüe coherente con el conocimiento acumulado sobre el tema y ajustada a la realidad trilingüe de la Comunidad.
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Conservation of soil organic carbon, biodiversity and the provision of other ecosystem services along climatic gradients in West Africa

  • Marks, E.
  • Aflakpui, G. K. S.
  • Nkem, N.
  • Poch, Rosa M.
  • Khouma, M.
  • Kokou, K.
  • Sagoe, R.
  • Sebastià, Ma. T.
Terrestrial carbon resources are major drivers of development in West Africa. The distribution of these resources co-varies with ecosystem type and rainfall along a strong Northeast-Southwest climatic gradient. Soil organic carbon, a strong indicator of soil quality, has been severely depleted in some areas by human activities, which leads to issues of soil erosion and desertification, but this trend can be altered with appropriate management. There is significant potential to enhance existing soil carbon stores in West Africa, with benefits at the global and local scale, for atmospheric CO2 mitigation as well as supporting and provisioning ecosystem services. Three key factors impacting carbon stocks are addressed in this review: climate, biotic factors, and human activities. Climate risks must be considered in a framework of global change, especially in West Africa, where landscape managers have few resources available to adapt to climatic perturbations. Among biotic factors, biodiversity conservation paired with carbon conservation may provide a pathway to sustainable development, and biodiversity conservation is also a global priority with local benefits for ecosystem resilience, biomass productivity, and provisioning services such as foodstuffs. Finally, human management has largely been responsible for reduced carbon stocks, but this trend can be reversed through the implementation of appropriate carbon conservation strategies in the agricultural sector, as shown by multiple studies. Owing to the strong regional climatic gradient, country-level initiatives will need to consider carbon sequestration approaches for multiple ecosystem types. Given the diversity of environments, global policies must be adapted and strategies developed at the national or sub-national levels to improve carbon storage above and belowground. Initiatives of this sort must act locally at farmer scale, and focus on ecosystem services rather than on carbon sequestration solely.
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Modeling the consequences of the demise and potential recovery of a keystone-species: wild rabbits and avian scavengers in Mediterranean landscapes

  • Cortés-Avizanda, Ainara
  • Colomer, M. Àngels (Maria Àngels)
  • Margalida, Antoni
  • Ceballos, Olga
  • Donázar, José A.
Restoration of demised keystone-species populations is an overriding concern in conservation biology. However, since no population is independent of its environment, progress is needed in predicting the efficacy of restoration in unstable ecological contexts. Here, by means of Population Dynamics P-system Models (PDP), we studied long-term changes in the population size of Egyptian vultures (Neophron percnopterus) inhabiting a Natural Park, northern Spain, to changes in the numbers of wild rabbits (Oryctolagus cuniculus), a keystone-species of Mediterranean ecosystems that have suffered >90% population decline after a hemorrhagic disease outbreak. Low availability of rabbit carcasses leads Egyptian vultures to extend their foraging activities to unprotected areas with higher non-natural mortality whereas growing numbers of griffon vultures (Gyps fulvus), a dominant competitor, progressively monopolize trophic resources resulting in a focal population decrease. Modeling shows that, even if keystone-species populations recover in core protected areas, the return to the original studied population size may be unfeasible, due to both the high non-natural mortality rates in humanized areas and long-term changes in the scavenger guild structure. Policy decisions aimed to restore keystone-species should rely on holistic approaches integrating the effects of spatial heterogeneity on both producer and consumer populations as well as within-guild processes.
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Hidrolizados de proteína: procesos y aplicaciones

  • Benítez, Ricardo
  • Ibarz Ribas, Alberto
  • Pagan i Gilabert, Jordi
En la hidrólisis enzimática de proteínas hasta péptidos o aminoácidos, por acción de enzimas proteolíticas, la composición final y, por tanto, el uso de los hidrolizados dependerá principalmente de la fuente proteica, del tipo de proteasa usada, de las condiciones de hidrólisis y del grado de hidrólisis alcanzado en la reacción. Los hidrolizados se utilizan ampliamente en la tecnología alimentaria por sus propiedades nutricionales o funcionales (solubilidad, poder emulsificante, capacidad espumante). En este trabajo se muestra la tendencia actual en las técnicas empleadas para la obtención de hidrolizados mediante enzimas y los diferentes métodos usados para el control de estos preparados; se indican además sus posibles aplicaciones.
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Design and Implementation of a Biomimetic Turtle Hydrofoil for an Autonomous Underwater Vehicle

  • Font Calafell, Davinia
  • Tresánchez Ribes, Marcel
  • Siegentahler, Cedric
  • Pallejà Cabrè, Tomàs
  • Teixidó Cairol, Mercè
  • Pradalier, Cedric
  • Palacín Roca, Jordi
This paper presents the design and implementation of a turtle hydrofoil for an Autonomous Underwater Vehicle (AUV). The final design of the AUV must have navigation performance like a turtle, which has also been the biomimetic inspiration for the design of the hydrofoil and propulsion system. The hydrofoil design is based on a National Advisory Committee for Aeronautics (NACA) 0014 hydrodynamic profile. During the design stage, four different propulsion systems were compared in terms of propulsion path, compactness, sealing and required power. The final implementation is based on a ball-andsocket mechanism because it is very compact and provides three degrees of freedom (DoF) to the hydrofoil with very few restrictions on the propulsion path. The propulsion obtained with the final implementation of the hydrofoil has been empirically evaluated in a water channel comparing different motion strategies. The results obtained have confirmed that the proposed turtle hydrofoil controlled with a mechanism with three DoF generates can be used in the future implementation of the planned AUV.
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Non existence of almost Moore digraphs of diameter three

  • Conde Colom, Josep
  • Gimbert i Quintilla, Joan
  • Miret, Josep M. (Josep Maria)
  • Moreno Chiral, Ramiro
  • Gonzàlez, J.
Almost Moore digraphs appear in the context of the degree/diameter problem as a class of extremal directed graphs, in the sense that their order is one less than the unattainable Moore bound M(d; k) = 1 + d + + dk, where d > 1 and k > 1 denote the maximum out-degree and diameter, respectively. So far, the problem of their existence has only been solved when d = 2; 3 or k = 2. In this paper, we prove that almost Moore digraphs of diameter k = 3 do not exist for any degree d. The enumeration of almost Moore digraphs of degree d and diameter k = 3 turns out to be equivalent to the search of binary matrices A ful lling that AJ = dJ and I+A+A2+A3 = J +P, where J denotes the all-one matrix and P is a permutation matrix . We use spectral techniques in order to show that such equation has no (0; 1)-matrix solutions. More precisely, we obtain the factorization in Q[x] of the characteristic polynomial of A, in terms of the cycle structure of P, we compute the trace of A and we derive a contradiction on some algebraic multiplicities of the eigenvalues of A. In order to get the factorization of det(xI - A) we determine when the polynomials Fn(x) = n(1 + x + x2 + x3) are irreducible in Q[x], where n(x) denotes the n-th cyclotomic polynomial, since in such case they become `big pieces' of det(xI - A). By using concepts and techniques from algebraic number theory, we prove that Fn(x) is always irreducible in Q[x], unless n = 1; 10. So, by combining tools from matrix and number theory we have been able to solve a problem of graph theory.
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Characterization of a Low-Cost Optical Flow Sensor When Using an External Laser as a Direct Illumination Source

  • Font Calafell, Davinia
  • Tresánchez Ribes, Marcel
  • Pallejà Cabrè, Tomàs
  • Teixidó Cairol, Mercè
  • Palacín Roca, Jordi
In this paper, a low cost optical flow sensor is combined with an external laser device to measure surface displacements and mechanical oscillations. The measurement system is based on applying coherent light to a diffuser surface and using an optical flow sensor to analyze the reflected and transferred light to estimate the displacement of the surface or the laser spot. This work is focused on the characterization of this measurement system, which can have the optical flow sensor placed at different angles and distances from the diffuser surface. The results have shown that the displacement of the diffuser surface is badly estimated when the optical mouse sensor is placed in front of the diffuser surface (angular orientation >150°) while the highest sensitivity is obtained when the sensor is located behind the diffuser surface and on the axis of the laser source (angular orientation 0°). In this case, the coefficient of determination of the measured displacement, R2 , was very high (>0.99) with a relative error of less than 1.29%. Increasing the distance between the surface and the sensor also increased the sensitivity which increases linearly, R2 = 0.99. Finally, this measurement setup was proposed to measure very low frequency mechanical oscillations applied to the laser device, up to 0.01 Hz in this work. The results have shown that increasing the distance between the surface and the optical flow sensor also increases the sensitivity and the measurement range.
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Prolonged Sitting Time: Barriers, Facilitators and Views on Change among Primary Healthcare Patients Who Are Overweight or Moderately Obese

  • Martínez Ramos, Elena
  • Martín Borràs, Carme
  • Trujillo, José Manuel
  • Giné Garriga, Maria
  • Martín Cantera, Carlos
  • Solà Gonfaus, Mercè
  • Castillo Ramos, Eva
  • Pujol Ribera, Enriqueta
  • Rodríguez, Dolors
  • Puigdomenech, Elisa
  • Beltran, Angela Maria
  • Serra Payà, Noemí
  • Gascón Catalán, Ana
  • Puig Ribera, Anna
Background and Objectives: Prolonged sitting time has negative consequences on health, although the population is not well aware of these harmful effects. We explored opinions expressed by primary care patients diagnosed as overweight or moderately obese concerning their time spent sitting, willingness to change, and barriers, facilitators, goals and expectations related to limiting this behaviour. Methods: A descriptive-interpretive qualitative study was carried out at three healthcare centres in Barcelona, Spain, and included 23 patients with overweight or moderate obesity, aged 25 to 65 years, who reported sitting for at least 6 hours a day. Exclusion criteria were inability to sit down or stand up from a chair without help and language barriers that precluded interview participation. Ten in-depth, semi-structured interviews (5 group, 5 individual) were audio recorded from January to July 2012 and transcribed. The interview script included questions about time spent sitting, willingness to change, barriers and facilitators, and the prospect of assistance from primary healthcare professionals. An analysis of thematic content was made using ATLAS.Ti and triangulation of analysts. Results: The most frequent sedentary activities were computer use, watching television, and motorized journeys. There was a lack of awareness of the amount of time spent sitting and its negative consequences on health. Barriers to reducing sedentary time included work and family routines, lack of time and willpower, age and sociocultural limitations. Facilitators identified were sociocultural change, free time and active work, and family surroundings. Participants recognized the abilities of health professionals to provide help and advice, and reported a preference for patient-centred or group interventions. Conclusions: Findings from this study have implications for reducing sedentary behaviour. Patient insights were used to design an intervention to reduce sitting time within the frame of the SEDESTACTIV clinical trial.
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Cloning and Functional Characterization of the Maize (Zea mays L.) Carotenoid Epsilon Hydroxylase Gene

  • Chang, Shu
  • Berman Quintana, Judit
  • Sheng, Yanmin
  • Wang, Yingdian
  • Capell Capell, Teresa
  • Shi, Lianxuan
  • Ni, Xiuzhen
  • Sandmann, Gerhard
  • Christou, Paul
  • Zhu, Changfu
The assignment of functions to genes in the carotenoid biosynthesis pathway is necessary to understand how the pathway is regulated and to obtain the basic information required for metabolic engineering. Few carotenoid ε-hydroxylases have been functionally characterized in plants although this would provide insight into the hydroxylation steps in the pathway. We therefore isolated mRNA from the endosperm of maize (Zea mays L., inbred line B73) and cloned a full-length cDNA encoding CYP97C19, a putative heme-containing carotenoid ε hydroxylase and member of the cytochrome P450 family. The corresponding CYP97C19 genomic locus on chromosome 1 was found to comprise a single-copy gene with nine introns. We expressed CYP97C19 cDNA under the control of the constitutive CaMV 35S promoter in the Arabidopsis thaliana lut1 knockout mutant, which lacks a functional CYP97C1 (LUT1) gene. The analysis of carotenoid levels and composition showed that lutein accumulated to high levels in the rosette leaves of the transgenic lines but not in the untransformed lut1 mutants. These results allowed the unambiguous functional annotation of maize CYP97C19 as an enzyme with strong zeinoxanthin ε-ring hydroxylation activity.
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Eleccions parlamentàries a la Lleida liberal, 1810-1868. Segona part: l'època isabelina (1845-1868)

  • Casals Bergés, Quintí
En el present treball s’agafaran tots els diputats que representaren la circumscripció de Lleida al Parlament espanyol i s’analitzaran totes les seves característiques (condició social, professió, dades econòmiques, nivell d’estudis, ideologia i participació política). Després s’agruparan en diverses variables (per sectors econòmics, riquesa, estudis, etc.) per arribar a les conclusions que defineixin la tipologia del diputat lleidatà dels primers 2/3 del segle XIX. Finalment, es compararan aquestes dades amb la resta de Catalunya i Espanya per veure si a Lleida se seguien uns paràmetres similars als de la resta de l’Estat., In the present work are taken all the deputies that represented in the Spanish Parliament Lleida and analyse all the characteristics (social status, profession, economic data, level of education, ideology and political participation). Then grouped into several variables (by economic sectors, wealth, education, etc.) to arrive at conclusions that define the type of Lleida deputy in the nineteenth century. Finally, we compare these data with the rest of Catalonia and Spain in Lleida to see if they were following parameters similar to those of the rest of the state.
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