998 resultados para Tostes, Celeida, 1929-1995


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Purpose – This study aims to investigate the pattern among 17 heterodox economic journals over a prolonged period to provide evidence about the social dynamics among the group of researchers who publish in them and the extent to which they hold or develop a collective identity as heterodox economists. Design/methodology/approach – Traditional approaches to citation analysis are extended by the use of techniques from social network analysis. In addition to citation counts, measures of network position and clique membership are used to identify key journals and turning points in a longitudinal analysis. Findings – Important shifts in the nature of citation within the network of journals are identified in the 1998-2001 period and evidence is found of the emergence of a collective identity. Research limitations/implications – The methods prove a valuable extension of citation analysis and also focus greater consideration on the social relationships that citations represent. They are well suited to addressing the principal limitation of the study, its restriction to journals within the defined community rather than journals in general. Originality/value – This extends traditional approaches to citation analysis, provides an important new technique in identifying emergent collective identities and provides insight into the history and nature of the heterodox economic community.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Long-term regional changes in phytoplankton biomass in the Northeast Atlantic and North Sea are investigated using data from the Continuous Plankton Recorder survey. During the last decade there have been large changes in the long-term variation in phytoplankton biomass in the Northeast Atlantic and North Sea. Most regions, particularly in the North Sea, have shown a considerable increase in phytoplankton biomass while the opposite pattern was seen in the northern oceanic region of the Northeast Atlantic. These different spatial responses show similar patterns of change to the decadal variability in sea surface temperature influenced by the North Atlantic Oscillation index. Two rare oceanographic events and their relationship to the interannual changes in phytoplankton biomass are discussed. The results highlight the importance of maintaining long-term biological monitoring programmes to assess the biological responses to slow oceanic/atmospheric processes and to rare or episodic physical events.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

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.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Los agrietamientos poligonales representan una forma común de modelado granítico cuyo origen y evolución continúa en fase de estudio, no existiendo una sistematización de estas estructuras diversas. Algunos autores explican su origen por procesos geodinámicos internos, relacionándolo con movimientos de planos de fractura en estados tardíos de consolidación magmática. Otros autores atribuyen su formación y desarrollo a factores externos relacionados con el régimen climático. La gran variedad de agrietamientos poligonales requiere la utilización de un número mayor de variables para definir los distintos orígenes, y las posibles interrelaciones entre los factores externos e internos, así como para explicar la evolución de dichas estructuras y avanzar en la clasificación de los patrones concretos. Este trabajo pretende contribuir a sistematizar los mecanismos que intervienen en el desarrollo de agrietamientos poligonales. Para ello se estudian únicamente agrietamientos poligonales formados sobre planos de fractura verticales o subverticales. En particular se establecen relaciones entre la presencia de agrietamientos poligonales y la red de fracturación, la altura de aparición, la orientación e inclinación de la pared, la morfología de las placas y la profundidad de incisión de las grietas perimetrales. Por otra parte, establece relaciones entre procesos geodinámicos internos y procesos de meteorización externos.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

En la Segunda Guerra Mundial la propaganda se convirtió en un campo de batalla más: en el caso de Italia era necesario crear en una opinión pública favorable a la guerra sin crear alarmismos. Para ello se utilizó uno de los instrumentos más eficaces para la propaganda del fascismo: el noticiario cinematográfico Luce. Este artículo analiza la representación que los noticiarios producidos desde 1940 hasta 1945 ofrecen de la Segunda Guerra Mundial. Se apuntan los temas más recurrentes, las características de las noticias sobre la guerra y se señalan las grandes ausencias debidas a la censura del Régimen de Mussolini.