Cálculo de emisiones de gases de efecto invernadero en edificios: análisis del funcionamiento de varias herramientas en diferentes climas

The first step to reduce greenhouse gas emissions from buildings is to be able to count them. If this counting is integrated in the design process the impact of architectural design strategies can be evaluated more easily and a building with reduced emissions can be developed. Fifty greenhouse gas calculators and energy modeling software were compared in the main areas in which buildings are responsible for carbon emissions: operation, water, construction, waste and transportation to and from the building. These tools had to be free and easy to use so that they could be used by everybody in the initial phases of the architectural design process, while providing sufficient precision to provide useful input to the designer. The effect of modifying the envelope insulation, the quality of the windows, the efficiency of the heating and cooling systems, and integrating direct gain and night ventilation, on operation emissions was evaluated with two energy modeling tools: HEED and Design Builder. Results demonstrated that implementing appropriate design strategies significantly reduced emissions from operation in all climates. An easy to implement protocol that combines several tools for GHG counting in buildings is provided at the end.El primer paso para reducir las emisiones de gases invernadero generadas por las edificaciones es el poder calcularlas adecuadamente. Si esta actividad se integra al proceso de diseño arquitectónico; entonces el impacto de las estrategias de diseño se puede evaluar más fácilmente; resultando un edificio con menores emisiones. Cincuenta herramientas de cálculo de emisiones y programas de modelaje se compararon en las áreas en las cuales los edificios son responsables de las emisiones de gases invernadero: operación; agua; construcción; basura; y transporte desde y hasta el edificio. Las herramientas comparadas debían ser fáciles de utilizar; pero con suficiente precisión para proveer información de utilidad al diseñador. El efecto en las emisiones; al modificar el aislante de las paredes y cubierta; cambiar la calidad de los vidrios; la eficiencia del sistema de calefacción y enfriamiento; y la integración de sistemas pasivos de ganancia solar directa o de enfriamiento pasivo por ventilación nocturna fueron evaluados con dos programas de modelaje energético: HEED y Design Builder. Los resultados de este análisis demuestran que la implementación apropiada de estrategias de diseño reducen significativamente las emisiones por operación en todos los climas. Al final del artículo se propone un protocolo que combina varias herramientas sencillas para calcular las emisiones de las diferentes fuentes

Student Housing: Trends, Preferences And Needs

To attract and retain students, universities are confronted with increased demand to provide housing options that meet the new expectations of the millennial generation.  Recent trends and housing preferences are examined.  The results of surveys detailing some of these new demands and how universities are attempting to address these demands are discussed.  Additionally, universities are under pressure to efficiently use their limited resources and, as government support for higher education declines, public universities are seeking other sources of funding for major projects. Suggestions are made for unique partnering and financing options.&nbsp

Biharmonic pattern selection

A new model to describe fractal growth is discussed which includes effects due to long-range coupling between displacements $u$. The model is based on the biharmonic equation $\nabla^{4}u =0$ in two-dimensional isotropic defect-free media as follows from the Kuramoto-Sivashinsky equation for pattern formation -or, alternatively, from the theory of elasticity. As a difference with Laplacian and Poisson growth models, in the new model the Laplacian of $u$ is neither zero nor proportional to $u$. Its discretization allows to reproduce a transition from dense to multibranched growth at a point in which the growth velocity exhibits a minimum similarly to what occurs within Poisson growth in planar geometry. Furthermore, in circular geometry the transition point is estimated for the simplest case from the relation $r_{\ell}\approx L/e^{1/2}$ such that the trajectories become stable at the growing surfaces in a continuous limit. Hence, within the biharmonic growth model, this transition depends only on the system size $L$ and occurs approximately at a distance $60 \%$ far from a central seed particle. The influence of biharmonic patterns on the growth probability for each lattice site is also analysed.Comment: To appear in Phys. Rev. E. Copies upon request to [email protected]

El dispositivo habitable

This paper explains the main concepts supporting the project "Habitar el Dispositivo" which was awarded a prize in the International Competition "25 Bioclimatical Houses" promoted by the "Instituto Tecnológico de Energías Renovables of Tenerife " and organized by the "Colegio de Arquitectos de Canarias" and sponsored by the "International Union of Architects". As opposed to bioclimatical houses which are the result of adding bioclimatical devices to an architectural project, the integration of bioclimatical and architectural concepts in a livable device is proposed. A digital model of the project was built to analyze sunlight and shadow behavior and computer simulations permitted to determine thermal performance. Average thermal satisfaction was 89.75 % during typical summer and winter 24 hour periods.Se presentan los conceptos fundamentales que respaldan la propuesta "Habitar el Dispositivo", premiada en el Concurso Internacional "25 Viviendas Bioclimáticas" promovido por el "Instituto Tecnológico de Energías Renovables del Cabildo de Tenerife", organizado por el "Colegio de Arquitectos de Canarias" y homologado por la "Unión Internacional de Arquitectos". Al contrario de la solución de añadir dispositivos a un proyecto de arquitectura, la propuesta integra conceptos bioclimáticos y arquitectónicos en un dispositivo habitable. Un modelo digital de la edificación permitió estudiar su volumetría y soleamiento en diferentes períodos del año, mientras que su comportamiento térmico se analizó con un programa de simulación en régimen dinámico. El promedio de personas satisfechas en días típicos de verano e invierno fue del 89,75 %

Telomere lengths in human oocytes, cleavage stage embryos and blastocysts

Telomeres are repeated sequences that protect the ends of chromosomes and harbour DNA-repair proteins. Telomeres shorten during each cell division in the absence of telomerase. When telomere length becomes critically short, cell senescence occurs. Telomere length therefore reflects both cellular ageing and capacity for division. We have measured telomere length in human germinal vesicle (GV) oocytes and pre-implantation embryos, by quantitative fluorescence in-situ hybridisation (Q-FISH), providing baseline data towards our hypothesis that telomere length is a marker of embryo quality. The numbers of fluorescent foci suggest that extensive clustering of telomeres occurs in mature GV stage oocytes, and in pre-implantation embryos. When calculating average telomere length by assuming that each signal presents one telomere, the calculated telomere length decreased from the oocyte to the cleavage stages, and increased between the cleavage stages and the blastocyst (11.12 vs 8.43 vs 12.22kb respectively, p<0.001). Other methods of calculation, based upon expected maximum and minimum numbers of telomeres, confirm that telomere length in blastocysts is significantly longer than cleavage stages. Individual blastomeres within an embryo showed substantial variation in calculated average telomere length. This study implies that telomere length changes according to the stage of pre-implantation embryo development

Cerramientos bioclimáticos para climas cálidos húmedos: la cuarta vivienda

In intertropical latitudes such as Venezuela with hot humid climates, building envelopes must reduce influence of solar radiation, and in these, roofs and windows must receive special attention. Venezuela is also the country with the highest energy consumption per capita in Iberoamérica, much of which is generated by air conditioning systems in residential buildings, and Maracaibo and the surrounding lake basin have some of the highest temperature and humidity values in Venezuela, which increase energy consumption even more. A bioclimatical house for this climate is proposed. This building incorporates principles from traditional indigenous, colonial and oil company houses in the Maracaibo lake basin to generate a new prototype, called the Fourth House.En climas cálidos húmedos como es el caso de grandes regiones de Venezuela, las envolventes deben reducir la influencia de la radiación solar y, por lo tanto, deben recibir atención especial. Venezuela es también el país con más alto consumo energético per capita en Iberoamérica, generado en su mayor parte por el uso de sistemas de aire acondicionado en las edificaciones residenciales. En Maracaibo y en los alrededores del Lago de Maracaibo se registran los valores más altos de temperatura y humedad en Venezuela, lo que incrementa, aún más, el consumo energético de las viviendas de estas regiones. La minimización del impacto de la radiación solar para lograr la reducción del consumo energético con un mayor bienestar térmico ha sido precisamente uno de los objetivos perseguidos con el desarrollo de una nueva vivienda bioclimática para la región del lago de Maracaibo. Esta incorpora principios de las tres viviendas bioclimáticas previas existentes en esa región: el palafito o vivienda tradicional indígena, la vivienda colonial republicana y la vivienda petrolera. Es por ello que esta vivienda ha sido llamada la Cuarta Vivienda

Galaxy evolution by color-log(n) type since redshift unity in the Hubble Ultra Deep Field

We explore the use of the color-log(n) plane (where n is the global Sersic index) as a tool for subdividing the high redshift galaxy population in a physically-motivated manner. Using a series of volume-limited samples out to z=1.5 in the Hubble Ultra Deep Field (UDF) we confirm the correlation between color-log(n) plane position and visual morphology observed locally and in other high redshift studies in the color and/or structure domain. Via comparison to a low redshift sample from the Millennium Galaxy Catalogue we quantify evolution by color-log(n) type, accounting separately for the specific selection and measurement biases against each. Specifically, we measure decreases in B-band surface brightness of 1.57 +/- 0.22 mag/sq.arcsec and 1.65 +/- 0.22 mag/sq.arcsec for `blue, diffuse' and `red, compact' galaxies respectively between redshift unity and the present day.Comment: 12 pages, 6 figures, to be published in A&A (accepted 29/10/08

Primary Cilia Mediate Diverse Kinase Inhibitor Resistance Mechanisms in Cancer.

Primary cilia are microtubule-based organelles that detect mechanical and chemical stimuli. Although cilia house a number of oncogenic molecules (including Smoothened, KRAS, EGFR, and PDGFR), their precise role in cancer remains unclear. We have interrogated the role of cilia in acquired and de novo resistance to a variety of kinase inhibitors, and found that, in several examples, resistant cells are distinctly characterized by an increase in the number and/or length of cilia with altered structural features. Changes in ciliation seem to be linked to differences in the molecular composition of cilia and result in enhanced Hedgehog pathway activation. Notably, manipulating cilia length via Kif7 knockdown is sufficient to confer drug resistance in drug-sensitive cells. Conversely, targeting of cilia length or integrity through genetic and pharmacological approaches overcomes kinase inhibitor resistance. Our work establishes a role for ciliogenesis and cilia length in promoting cancer drug resistance and has significant translational implications.This research was partly funded by the Institute of Cancer Research and by grants from Sarcoma UK (to B.E.T. [14.2014] and P.H.H. [3.2014]), Kent Cancer Trust (to M.M.), Hilfe fuer Krebskranke Kinder Frankfurt e.V. and Frankfurter Stiftung fuer Krebskranke Kinder (to J.C.), CRUK-CI Core Grant (C14303/A17197), and S.H.D. Fellowship (Wellcome Trust/Royal Society [107609]) (to M.D.R.). B.E.T. was supported by an ICR fellowship

The presence and predictors of complicated grief symptoms in perinatally-bereaved mothers from a bereavement support organization

The present study investigated the presence and possible predictors of complicated grief symptoms in perinatally-bereaved mothers (N = 121) up to 5 years post-bereavement. The presence of complicated grief scores in the clinical range was 12.4%, which is higher than in many other bereaved populations, and the presence of other living children may protect against the development of complicated grief symptoms. The majority of the women were able to negotiate a perinatal loss without developing complicated grief; however, there remains an important group of women who up to 5 years later score in the clinical range for complicated grief symptoms