Thermal energy storage with phase change materials in building envelopes

Els materials de canvi de fase (PCM) han estat considerats per a l’emmagatzematge tèrmic en edificis des de 1980. Amb la inclusió dels PCM en plaques de guix, guix, formigó o altres materials que s’utilitzen per a cobrir les parets, l’emmagatzematge tèrmic pot ser part de les estructures fins i tot en edificis lleugers. Les noves tècniques de microencapsulació han obert moltes possibilitats en aplicacions per a edificis. El treball que es presenta és el desenvolupament d’un formigó innovador mesclat amb PCM microencapsulat, amb un punt de fusió de 26 oC i una entalpia de canvi de fase de 110 kJ/kg. El primer experiment va ser la inclusió del PCM microencapsulat dins del formigó i la construcció d’una caseta amb aquest nou formigó-PCM. Es va construir una segona caseta al costat de la primera amb les mateixes característiques i orientació però amb formigó convencional que serveix com a referència. Durant els anys 2005 i 2006 es va analitzar el comportament d’ambdues casetes i més tard es va edificar un mur Trombe a la paret sud de totes dues per investigar la seva influència durant la tardor i l’hivern.

Pros y contras de una sociedad profesional transparente

L'article aporta una relació d'avantatges i inconvenients, des del punt de vista fiscal, de les societats professionals en règim de transparència.

Lack of support for the association between facial shape and aggression: a reappraisal based on a worldwide population genetics perspective

Antisocial and criminal behaviors are multifactorial traits whose interpretation relies on multiple disciplines. Since these interpretations may have social, moral and legal implications, a constant review of the evidence is necessary before any scientific claim is considered as truth. A recent study proposed that men with wider faces relative to facial height (fWHR) are more likely to develop unethical behaviour mediated by a psychological sense of power. This research was based on reports suggesting that sexual dimorphism and selection would be responsible for a correlation between fWHR and aggression. Here we show that 4,960 individuals from 94 modern human populations belonging to a vast array of genetic and cultural contexts do not display significant amounts of fWHR sexual dimorphism. Further analyses using populations with associated ethnographical records as well as samples of male prisoners of the Mexico City Federal Penitentiary condemned by crimes of variable level of inter-personal aggression (homicide, robbery, and minor faults) did not show significant evidence, suggesting that populations/individuals with higher levels of bellicosity, aggressive behaviour, or power-mediated behaviour display greater fWHR. Finally, a regression analysis of fWHR on individual"s fitness showed no significant correlation between this facial trait and reproductive success. Overall, our results suggest that facial attributes are poor predictors of aggressive behaviour, or at least, that sexual selection was weak enough to leave a signal on patterns of between- and within-sex and population facial variation.

El show de las stock options

El presente artículo comenta las consecuencias tributarias en Derecho español del uso de stock options.

Información y asistencia a los obligados tributarios

Se comenta la nueva Ley General Tributaria, concretamente en lo relativo a las actuaciones de información, asistencia y colaboración social.

Stable isotopes indicate population structuring in the Southwest Atlantic population of right whales

From the early 17th century to the 1970s southern right whales, Eubalaena australis, were subject to intense exploitation along the Atlantic coast of South America. Catches along this coast recorded by whalers originally formed a continuum from Brazil to Tierra del Fuego. Nevertheless, the recovery of the population has apparently occurred fragmentarily, and with two main areas of concentration, one off southern Brazil (Santa Catarina) and another off central Argentina (Peninsula Valdés). This pattern suggests some level of heterogeneity amongst the population, which is apparently contradicted by records that traced individuals moving throughout the whole geographical extension covered by the species in the Southwest Atlantic. To test the hypothesis of the potential occurrence of discrete subpopulations exploiting specific habitats, we investigated N, C and O isotopic values in 125 bone samples obtained from whaling factories operating in the early 1970s in southern Brazil (n = 72) and from contemporary and more recent strandings occurring in central Argentina (n = 53). Results indicated significant differences between the two sampling areas, being δ13C and δ18O values significantly higher in samples from southern Brazil than in those from central Argentina. This variation was consistent with isotopic baselines from the two areas, indicating the occurrence of some level of structure in the Southwest Atlantic right whale population and equally that whales more likely feed in areas commonly thought to exclusively serve as nursing grounds. Results aim at reconsidering of the units currently used in the management of the southern right whale in the Southwest Atlantic Ocean. In the context of the current die-off affecting the species in Peninsula Valdés, these results also highlight the necessity to better understand movements of individuals and precisely identify their feeding areas.

Tasa Tobin: arena en las ruedas

El artículo trata de un impuesto concebido por James Tobin al que se ha llamado la tasa Tobin. La idea de esta tasa es brillante y bastaría una decidida voluntad política de llevarla a cabo para que fuese efectiva.

HARVEST LABOR QUALITY AND PRODUCTIVITY:CASE STUDY OF CHERRY GROWING IN CHILE

In Chile, the cherry tree has been one of the fastest growing and most profitable crops in the last ten years. However, increasing production costs, the scarcity of hired labor, and unfavorable exchange rates have reduced the productivity and competitiveness of the Chilean fruit sector. The aim of this article is to evaluate the harvest labor quality in cherry growing in Chile through the use of productivity indicators. A harvest labor evaluation system (HLES) was designed and four indicators were measured: Average Weight of Harvested Box, Average Daily Production per Worker, Percent of Export Fruit, and Percent of Fruit Discarded. Significant differences werefound between the 2010/11 season (with the HLES implementation) and the previous seasons without HLES. The average worker yield, average weight of a filled box, and fruit quality improved, while the amount of discarded fruit decreased. Hired labor management in agriculture is crucial for improving the productivity of the fresh fruit export producers. The use of HLES and the adoption of new technologies could help to solve the competitiveness problem in the Chilean fruit sector.

Las claves de la financiación autonómica: José V. Sevilla Segura, Crítica, Barcelona 2001

Reseña del libro 'Las claves de la financiación autonómica', de José V. Sevilla Segura (Barcelona: Crítica, 2001).

Incentivos fiscales a la inversión empresarial: catálogo y fundamento constitucional

La vigente ley reguladora del Impuesto sobre Sociedades (Ley núm. 43, de 27 de diciembre de 1995) presenta numerosos beneficios fiscales. El objetivo de este trabajo es el de describir y desgranar el contenido de una parte de dichos beneficios, indagando su fundamento constitucional.

Acuerdo entre KPMG y el IRS

La década de los noventa arrancó en EEUU con una prosperidad económica que infló las cuentas de resultados de un buen número de empresas y particulares. Muchas empresas de auditoría, consultoras y despachos de abogados comercializaron por entonces 'productos financieros' cuyo principal atractivo consistía en poner ahorros y rendimientos a buen recaudo, invertir a refugio de la acción del Tesoro público: Tax-Shelter. En España fueron bancos y cajas quienes transitaron estas líneas de negocio: primas únicas, cesiones de crédito, bonos austríacos.

Evolución y reforma del sistema financiero de energía eléctrica

En el presente trabajo se hace, primero, un análisis de la evolución y situación actual del sistema financiero de la energía eléctrica en España, hasta la Ley 24/2013. Tras un estudio pormenorizado, a continuación, de una de las ideas que se consideró para mejorar sus ingresos -el establecimiento de una tasa sobre las energías renovables- se pasa revista, por último, a lo que en los últimos meses se ha hecho al respecto, tanto en cuanto al incremento de los ingresos como en lo relativo a la atenuación de sus costes.

Snail blocks the cell cycle and confers resistance to cell death

The Snail zinc-finger transcription factors trigger epithelial-mesenchymal transitions (EMTs), endowing epithelial cells with migratory and invasive properties during both embryonic development and tumor progression. During EMT, Snail provokes the loss of epithelial markers, as well as changes in cell shape and the expression of mesenchymal markers. Here, we show that in addition to inducing dramatic phenotypic alterations, Snail attenuates the cell cycle and confers resistance to cell death induced by the withdrawal of survival factors and by pro-apoptotic signals. Hence, Snail favors changes in cell shape versus cell division, indicating that with respect to oncogenesis, although a deregulation/increase in proliferation is crucial for tumor formation and growth, this may not be so for tumor malignization. Finally, the resistance to cell death conferred by Snail provides a selective advantage to embryonic cells to migrate and colonize distant territories, and to malignant cells to separate from the primary tumor, invade, and form metastasis.