Convergence

Since at least the early 1990s with the publication of groundbreaking works such as Manovich's The Language of New Media, the rise of digital and online media into every facet of our lives has been conceptualized through distinctions between " new " and " old " media. Yet, scholars have recently started to criticize such concepts, arguing that they are inappropriate to describe media change and that they do not help improve our understanding of the relationship between different media in contemporary societies. Approaches to the biography and social life of media have examined how definitions of oldness and newness are attributed to technologies and artefacts throughout their lifetime, providing an interpretative model to rethink processes such as convergence, media encounters, and the transformations that media technologies and practices experience throughout time. This special issue will further advance these reflections. It aims to illuminate places, cases, and contexts where distinctions between old and new media break down, and to propose alternative theoretical frameworks that redefine media change and the interaction between different media. Papers are invited that interrogate how changing definitions of old and new media inform the trajectory of specific media as well as their interrelations, moving away from rigid conceptions of oldness and newness to emphasise, instead, the persistent changes that characterise our relationship with media objects and technologies.

The convergence hypothesis maintains that an economy whose productivity lags behind other economies has a potential to grow faster. We introduce a procedure for testing this hypothesis and apply it to 24 OECD countries for the period 1950 ± 1990. Our approach is an attempt to capture the economics of the convergence hypothesis, while avoiding the problems associated with two popular tests of convergence, namely b-convergence and s-convergence. An application of an ARMA process to our sample data finds only modest support for the convergence hypothesis in the OECD during the postwar era. Patterns of investment, government consumption, and exports largely explain the observed convergence in the OECD. D 2001 Elsevier Science Inc. All rights reserved.

The morphology of the Rivera plate subducted beneath the Jalisco block in western Mexico is determined from accurately located hypocenters of locally recorded microearthquakes, and from earthquakes with magnitude mb>4.5 recorded at teleseismic distances. The hypocenters of these latter earthquakes are relocated, and for five of them the focal depth is constrained by the inversion of long-period body waves. The Wadati-Benioff zone inferred from these data indicates a steep subduction of the Rivera plate that resembles the geometry of subduction of the Cocos plate beneath Central America. It is, however, very different from the shallower and almost subhorizontal subduction of the Cocos plate observed in southern Mexico, southeast of this region. The Rivera plate is comparable to the Juan de Fuca plate in terms of the small areal extent, young seafloor age, low relative velocity, and low teleseismic activity in the subduction zone. This study shows that the dip of both the Juan de Fuca and Rivera plates are similar once they are decoupled from the overriding continental crust. The downgoing Rivera plate initially starts with a dip of-10 ø down to a depth of 20 km and then increases gradually to a constant dip of-50 ø below a depth of 40 km. Intermediatedepth seismicity is low in this zone associated with the subduction of the slow (2 cm/yr) and young (9 m.y.) Rivera plate. The maximum depth extent of earthquakes observed in the Rivera subduction zone is about 130 km. The andesitic, calc-alkaline Colima volcano appears to be directly related to the subduction of the Rivera plate. To the NW of this volcano, the observed Quaternary volcanism in the Jalisco block, which is parallel to the trench, may also be explained by the subduction of the Rivera plate. Int., 31,247-252, 1991. Taber, J. and S. Smith, Seismicity and focal mechanisms associated with the subduction of the Juan de Fuca plate beneath the Olympic peninsula, Washington, Bull. Seismol. Soc. Am., 75, 237-249, 1985.