Smoothness of time functions and the metric splitting of globally hyperbolic spacetimes

The folk questions in Lorentzian Geometry, which concerns the smoothness of time functions and slicings by Cauchy hypersurfaces, are solved by giving simple proofs of: (a) any globally hyperbolic spacetime $(M,g)$ admits a smooth time function $\tau$ whose levels are spacelike Cauchy hyperfurfaces and, thus, also a smooth global splitting $M= \R \times {\cal S}$, $g= - \beta(\tau,x) d\tau^2 + \bar g_\tau$, (b) if a spacetime $M$ admits a (continuous) time function $t$ (i.e., it is stably causal) then it admits a smooth (time) function $\tau$ with timelike gradient $\nabla \tau$ on all $M$.Comment: 9 pages, Latex, to appear in Commun. Math. Phys. Some comments on time functions and stably causal spacetimes are incorporated, and referred to gr-qc/0411143 for further detail

The Localisation of Video Games

The present thesis is a study of the translation of video games with a particular emphasis on the Spanish-English language pair, although other languages are brought into play when they offer a clearer illustration of a particular point in the discussion. On the one hand, it offers a descriptive analysis of the video game industry understood as a global phenomenon in entertainment, with the aim of understanding the norms governing present game development and publishing practices. On the other hand, it discusses particular translation issues that seem to be unique to these entertainment products due to their multichannel and polysemiotic nature, in which verbal and nonverbal signs are intimately interconnected in search of maximum game interactivity. Although this research positions itself within the theoretical framework of Descriptive Translation Studies, it actually goes beyond the mere accounting of current processes to propose changes whenever professional practice seems to be unable to rid itself of old unsatisfactory habits. Of a multidisciplinary nature, the present thesis is greatly informed by various areas of knowledge such as audiovisual translation, software localisation, computer assisted translation and translation memory tools, comparative literature, and video game production and marketing, amongst others. The conclusions are an initial breakthrough in terms of research into this new area, challenging some of the basic tenets current in translation studies thanks to its multidisciplinary approach, and its solid grounding on current game localisation industry practice. The results can be useful in order to boost professional quality and to promote the training of translators in video game localisation in higher education centres.Open Acces

Multiple hypothesis testing and clustering with mixtures of non-central t-distributions applied in microarray data analysis

Multiple testing analysis, based on clustering methodologies, is usually applied in Microarray Data Analysis for comparisons between pair of groups. In this paper, we generalize this methodology to deal with multiple comparisons among more than two groups obtained from microarray expressions of genes. Assuming normal data, we define a statistic which depends on sample means and sample variances, distributed as a non-central t-distribution. As we consider multiple comparisons among groups, a mixture of non-central t-distributions is derived. The estimation of the components of mixtures is obtained via a Bayesian approach, and the model is applied in a multiple comparison problem from a microarray experiment obtained from gorilla, bonobo and human cultured fibroblasts.Clustering, MCMC computation, Microarray analysis, Mixture distributions, Multiple hypothesis testing, Non-central t-distribution

Maestres y señores de naos, con particular referencia a los onubenses y la financiación de la Carrera de Indias

Tomo I ; págs. 105-12