On the diffusion approximation of the stationary radiative transfer equation with absorption and emission

We study the situation in which the distribution of temperature a body is due to its interaction with radiation. We consider the boundary value problem for the stationary radiative transfer equation under the assumption of the local thermodynamic equilibrium. We study the diffusion equilibrium approximation in the absence of scattering. We consider absorption coefficient independent of the frequency $\nu$ (the so-called Grey approximation) and the limit when the photons' mean free path tends to zero, i.e. the absorption coefficient tends to infinity. We show that the densitive of radiative energy $u$, which is proportional to the fourth power of the temperature due to the Stefan-Boltzmann law, solves in the limit an elliptic equation where the boundary value can be determined uniquely in terms of the original boundary condition. We derive formally with the method of matched asymptotic expansions the boundary condition for the limit problem and we prove rigorously the convergence to the solution of the limit problem with a careful analysis of some non-local integral operators. The method developed here allows to prove all the results using only maximum principle arguments.Comment: 62 pages, 9 Figure

Estilos educativos parentales y su relación con la socialización en adolescentes

En el presente artículo se analiza la importancia de la familia sobre el desarrollo social óptimo del hijo adolescente. Los objetivos de esta investigación son evaluar la socialización de 80 sujetos entre 11 y 14 años a través de su conducta social y sus habilidades sociales, estudiar el modelo de crianza de los padres y las madres y su relación con el nivel educativo de los mismos, y analizar la correlación entre el estilo de socialización utilizado por los padres y el ajuste social del hijo. Los instrumentos utilizados han sido la Batería de Socialización (BAS-3), la Escala de Habilidades Sociales (EHS) y la Escala de Socialización Parental en la Adolescencia (ESPA29). Los resultados muestran una relación significativa entre la competencia social del adolescente y muchas dimensiones que conforman el estilo educativo parental. Además se crean modelos predictores de diversas variables relacionadas con la conducta social y las habilidades sociales.The current article examines the influence of families on the optimum social development of adolescents. The objectives of this study include the assessment of socialization in 80 subjects from age 11 to 14 through their social behavior and skills, the research of parenting styles and its relation to educational attainment and the analysis of the correlation between the parents’ socialization and the children’s social adjustment. The instruments used were the Socialization Battery (BAS-3), the Social Skills Scale in Adolescents (EHS) and the Parental Socialization Scale in Adolescent (ESPA29). The results show a significant relationship between the children’s social competence and many dimensions of the parenting styles. Furthermore, some models are created to predict variances related to social behavior and skills

Compactness and existence theory for a general class of stationary radiative transfer equations

In this paper, we study the steady-states of a large class of stationary radiative transfer equations in a $C^1$ convex bounded domain. Namely, we consider the case in which both absorption-emission and scattering coefficients depend on the local temperature $T$ and the radiation frequency $\nu.$ The radiative transfer equation determines the temperature of the material at each point. The main difficulty in proving existence of solutions is to obtain compactness of the sequence of integrals along lines that appear in several exponential terms. We prove a new compactness result suitable to deal with such a non-local operator containing integrals on a line segment. On the other hand, to obtain the existence theory of the full equation with both absorption and scattering terms we combine the compactness result with the construction of suitable Green functions for a class of non-local equations

Drawing planar graphs with prescribed face areas

This thesis deals with planar drawings of planar graphs such that each interior face has a prescribed area. Our work is divided into two main sections. The rst one deals with straight-line drawings and the second one with orthogonal drawings. For straight-line drawings, it was known that such drawings exist for all planar graphs with maximum degree 3. We show here that such drawings exist for all planar partial 3-trees, i.e., subgraphs of a triangulated planar graph obtained by repeatedly inserting a vertex in one triangle and connecting it to all vertices of the triangle. Moreover, vertices have rational coordinates if the face areas are rational, and we can bound the resolution. For orthogonal drawings, we give an algorithm to draw triconnected planar graphs with maximum degree 3. This algorithm produces a drawing with at most 8 bends per face and 4 bends per edge, which improves the previous known result of 34 bends per face. Both vertices and bends have rational coordinates if the face areas are rational

In Vitro Culture of ‘Myrobalan’ (Prunus cerasifera Ehrh.) Embryos

The definitive version is available at: http://hortsci.ashspublications.org/In vitro embryo culturing has arisen as a powerful tool for embryo germination of low-viability seeds. This tool has been used to germinate seeds of early-maturing or hybrid Prunus species. ‘Myrobalan’ (Prunus cerasifera Ehrh.) is a widely used rootstock for plum and apricot cultivars and its interspecific hybrids have a clear potential for breeding purposes. However, early seed abortion is often a problem in interspecific crosses because no protocol has been established yet for ‘Myrobalan’ seeds. In this work, we developed a procedure for in vitro germination of embryos of different sizes. Various factors affecting embryo germination such as the culture media, the presence of cotyledons, the stratification temperature, and the embryo size were tested in three different ‘Myrobalan’ clones. The developed protocol includes the use of full embryos that were stratified at 4 °C and cultured in C2d culture medium. The germination rate was strongly affected by the embryo size and reached 90% germination with intermediate- to large-sized embryos (6.5 to 10 mm). However, smaller embryos could also be germinated, and up to 30% germination was achieved with 0.5- to 2-mm long embryos. The results obtained here provide a protocol for in vitro germination of ‘Myrobalan’ embryos that will likely be helpful in breeding programs.This work was partially supported by the INIA-FEDER project RF2008-00029-C02-01 and by the Grupo de Excelencia A-43 (Gobierno de Aragón).Peer reviewe

Desarrollo de tejido vascular en etapas precoces de combinaciones de injerto/patrón de diferente compatibilidad

Comunicación presentada en el X Congreso Nacional de Ciencias Hortícolas (Pontevedra, mayo de 2003), en su apartado "Fruticultura".El objetivo de este trabajo fue encontrar diferencias tempranas de compatibilidad en el desarrollo de uniones entre yemas del cultivar Moniquí de albaricoquero injertadas en plantas híbridas provenientes de cruzamientos interespecíficos entre albaricoquero y ciruelo Mirobolán.Peer reviewe

From water to energy : the virtual water content and water footprint of biofuel consumption in Spain

Energy diversification and the use of renewable energy sources are key points in the European energy strategy. Biofuels are the most popular renewable resource option for the transport sector, and the European Union has established objectives that the Member States must adopt and implement. However, biofuel production at such a scale requires a considerable amount of water resources, and this water-energy nexus is rarely taken into account. This paper shows the strong nexus between water and energy in biofuel production and estimates the virtual water (VW) content and the water footprint (WF) from the raw material production that will be needed to reach the Spanish targets for biofuel consumption by 2010. The results show how the impact of such targets on the global and local water situation could be reduced through virtual water imports and, at the same time, how these imports could increase Spain's water and energy dependence. Hence, in order to manage water from an integral perspective of the territory, the inclusion of biofuel consumption objectives should go hand in hand with measures to reduce the demand of energy in the transport sector

How to improve the early diagnosis of Trypanosoma cruzi infection: Relationship between validated conventional diagnosis and quantitative DNA amplification in congenitally infected children

BACKGROUND: According to the Chagas congenital transmission guides, the diagnosis of infants, born to Trypanosoma cruzi infected mothers, relies on the detection of parasites by INP micromethod, and/or the persistence of T. cruzi specific antibody titers at 10-12 months of age. METHODOLOGY AND PRINCIPAL FINDINGS: Parasitemia levels were quantified by PCR in T. cruzi-infected children, grouped according to the results of one-year follow-up diagnosis: A) Neonates that were diagnosed in the first month after delivery by microscopic blood examination (INP micromethod) (n = 19) had a median parasitemia of 1,700 Pe/mL (equivalent amounts of parasite DNA per mL); B) Infants that required a second parasitological diagnosis at six months of age (n = 10) showed a median parasitemia of around 20 Pe/mL and 500 Pe/mL at 1 and 6 months old, respectively, and C) babies with undetectable parasitemia by three blood microscopic observations but diagnosed by specific anti - T. cruzi serology at around 1 year old, (n = 22), exhibited a parasitemia of around 5 Pe/mL, 800 Pe/mL and 20 Pe/mL 1, 6 and 12 month after delivery, respectively. T. cruzi parasites were isolated by hemoculture from 19 congenitally infected children, 18 of which were genotypified as DTU TcV, (former lineage TcIId) and only one as TcI. SIGNIFICANCE: This report is the first to quantify parasitemia levels in more than 50 children congenitally infected with T. cruzi, at three different diagnostic controls during one-year follow-up after delivery. Our results show that the parasite burden in some children (22 out of 51) is below the detection limit of the INP micromethod. As the current trypanocidal treatment proved to be very effective to cure T. cruzi - infected children, more sensitive parasitological methods should be developed to assure an early T. cruzi congenital diagnosis.Fil: Bua, Jacqueline Elena. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Volta, Bibiana Julieta. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; ArgentinaFil: Perrone, Alina Elizabeth. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Scollo, Karenina. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; ArgentinaFil: Velázquez, Elsa Beatriz. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ruiz, Andrés Mariano. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: de Rissio, Ana María. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; ArgentinaFil: Cardoni, Rita Liliana. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Health : the main ally for support of the anti-tobacco law in Spain

Objective: To determine the sociodemographic characteristics and opinions that predict citizens' attitudes towards the anti-tobacco law in Spain. Methods: Data was analyzed from a telephone survey on smoking habits conducted among citizens of Spain in 2008 by the Centro de Investigaciones Sociológicas (CIS). The sample was stratified by region and size of habitat, establishing age and sex quotas. A descriptive analysis is provided of the main results. A forward stepwise logistic regression analysis was performed with opinions about the anti-tobacco law as a dependent variable and sociodemographic characteristics of the respondents as independent variables. Results: The perceived effectiveness of the law in terms of health benefits and reduction in number of smokers and cigarettes consumed has the greatest predictive power on support for the anti-tobacco law. Conclusion: Policies aimed at improving public health must meet with the support of citizens. In order to garner this support it is essential that citizens be informed about the effectiveness and health benefits of restrictive legislation such as anti-tobacco laws.Analizar qué características sociodemográficas y de opinión predicen el respaldo de los ciudadanos a la Ley antitabaco en España. Métodos: Se han analizado los datos de una encuesta telefónica realizada en 2008 por el Centro de Investigaciones Sociológicas (CIS) sobre hábitos relacionados con el tabaco a población española, estableciendo cuotas de sexo y edad y con distribución por comunidades autónomas y tamaño de hábitat. Se ha realizado un análisis descriptivo de los principales resultados y un análisis de regresión logística (stepwise forward). La variable dependiente es la posición ante la ley antitabaco, y las variables independientes, las características sociodemográficas del entrevistado y las opiniones sobre la ley. Resultados: Lo que más predice la posición favorable a la ley es la apreciación de su efectividad, es decir, la percepción de que la ley ayuda a mejorar la salud de la población y a reducir el número de fumadores y la cantidad de cigarrillos fumados. Conclusión: Es necesario que la población apoye políticas sanitarias que son claramente beneficiosas para la salud pública en general. En este sentido, la información sobre la efectividad de la ley se postula como un elemento decisivo para conseguir el respaldo popular necesario para llevar a cabo políticas restrictivas y/o prohibitivas