How mathematics is defined and measured in PISA 2003

Description of some variables used in PISA 2003 project to asses competences.

[Conference report] Magic and mathematics: The life and work of John Dee. National Maritime Museum, Greenwich, 13-14 June 2003

Tony Mann provides a report of a two-day meeting "Magic and mathematics: The life and work of John Dee" held from 13-14 June 2003 at the National Maritime Museum, Greenwich.

Decadal fluctuations in North Atlantic water inflow in the North Sea between 1958-2003: impacts on temperature and phytoplankton populations

The circulation of Atlantic water along the European continental slope, in particular the inflow into the North Sea, influences North Sea water characteristics with consequent changes in the environment affecting plankton community dynamics. The long-term effect of fluctuating oceanographic conditions oil the North Sea, pelagic ecosystem is assessed. It is shown that (i) there are similar regime shifts in the inflow through the northern North Sea and in Sea, Surface Temperature, (ii) long-term phytoplankton trends are influenced by the inflow only in some North Sea regions, and (iii) the spatial variability in chemicophysical and biological parameters highlight the influence of smaller scale processes.

Temporal changes in total and size-fractioned chlorophyll-a in surface waters of three provinces in the Atlantic Ocean (September to November) between 2003 and 2010

Phytoplankton total chlorophyll concentration (TCHLa) and phytoplankton size structure are two important ecological indicators in biological oceanography. Using high performance liquid chromatography (HPLC) pigment data, collected from surface waters along the Atlantic Meridional Transect (AMT), we examine temporal changes in TCHLa and phytoplankton size class (PSC: micro-, nano- and pico-phytoplankton) between 2003 and 2010 (September to November cruises only), in three ecological provinces of the Atlantic Ocean. The HPLC data indicate no significant change in TCHLa in northern and equatorial provinces, and an increase in the southern province. These changes were not significantly different to changes in TCHLa derived using satellite ocean-colour data over the same study period. Despite no change in AMT TCHLa in northern and equatorial provinces, significant differences in PSC were observed, related to changes in key diagnostic pigments (fucoxanthin, peridinin, 19′-hexanoyloxyfucoxanthin and zeaxanthin), with an increase in small cells (nano- and pico-phytoplankton) and a decrease in larger cells (micro-phytoplankton). When fitting a three-component model of phytoplankton size structure — designed to quantify the relationship between PSC and TCHLa to each AMT cruise, model parameters varied over the study period. Changes in the relationship between PSC and TCHLa have wide implications in ecology and marine biogeochemistry, and provide key information for the development and use of empirical ocean-colour algorithms. Results illustrate the importance of maintaining a time-series of in-situ observations in remote regions of the ocean, such as that acquired in the AMT programme.

Shark personalities? Repeatability of social network traits in a widely distributed predatory fish. Behavioral Ecology and Sociobiology, 68, 1995-2003.

Interest in animal personalities has generated a burgeoning literature on repeatability in individual traits such as boldness or exploration through time or across different contexts. Yet, repeatability can be influenced by the interactive social strategies of individuals, for example, consistent inter-individual variation in aggression is well documented. Previous work has largely focused on the social aspects of repeatability in animal behaviour by testing individuals in dyadic pairings. Under natural conditions, individuals interact in a heterogeneous polyadic network. However, the extent to which there is repeatability of social traits at this higher order network level remains unknown. Here, we provide the first empirical evidence of consistent and repeatable animal social networks. Using a model species of shark, a taxonomic group in which repeatability in behaviour has yet to be described, we repeatedly quantified the social networks of ten independent shark groups across different habitats, testing repeatability in individual network position under changing environments. To understand better the mechanisms behind repeatable social behaviour, we also explored the coupling between individual preferences for specific group sizes and social network position. We quantify repeatability in sharks by demonstrating that despite changes in aggregation measured at the group level, the social network position of individuals is consistent across treatments. Group size preferences were found to influence the social network position of individuals in small groups but less so for larger groups suggesting network structure, and thus, repeatability was driven by social preference over aggregation tendency.

Modelos de desarrollo, unificación y “desterritorialización”.

El presente estudio tiene el objetivo de ofrecer una visión general sobre los Modelos de Desarrollo y Organización Territorial desde la perspectiva de las relaciones entre el medio urbano, “rururbano” y rural, en España. Para ello, tras conocer y valorar los enfoque conceptuales y temáticos, se estudia el crecimiento urbano en nuestro país en las últimas décadas, analizando de manera pormenorizada la importancia que ha cobrado y cobra la aplicación legislativa de leyes, planes y normas, tanto en el propio crecimiento urbano como en la demanda de viviendas en las ciudades españolas y, de igual modo, la vinculación de ambas con el precio de las viviendas, relacionándolo con la problemática de la “rururbanización”, y del medio rural.

La influencia de las nuevas tecnologías en los hábitos de lectura: análisis de las noticias de "El País", "El Mundo" y "ABC" (2011)

En este texto se explica el cambio de hábitos que ha supuesto la lectura en formato digital. Se indican los factores que determinan la selección un formato u otro, al igual que la situación en la que se encuentra la lectura digital en España. Para ello, se analizan las noticias sobre este tema encontradas en los periódicos: ABC, El País y El Mundo durante el año 2011 -período relevante para la lectura digital- y se comparan con los resultados de las encuestas de AIMC, FGEE, etc., con el fin de sacar conclusiones certeras.

"Google News" y el impacto de la Ley de Propiedad Intelectual en la prensa: un nuevo amanecer para la información

2015 se recordará como el gran año del cambio en los medios de comunicación, especialmente para la prensa. A lo largo del mismo se ha llevado a cabo una enconada lucha entre los editores y Google News, a la que se han sumado Yahoo News, Facebook, LinkedIn, Twitter, etc., para determinar quién debe pagar por los contenidos, quién los creará, quién los distribuirá y quién y cómo los leerá. Nuevos pactos para nuevos lectores. Nuevos acuerdos para reflotar económicamente la prensa. Y todo ello bajo el paraguas de la Ley de Propiedad Intelectual en España y otras similares que se irán publicando o adaptando en Europa. Se ofrece un estudio y análisis de la situación previa al establecimiento de dicha ley y las consecuencias de su aplicación.