A Pure Graph-Based Solution to the SCG-1 Initiative

Abstract. This paper answers the SCG-1 initiative. The room allocation problem provided has been solved in a generic and automatic way. The solution is based on a totally declarative formal model. Basic constructs are simple graphs and the fundamental operation for doing reasonings is the graph morphism known as projection. The other formal constructs are rules and constraints defined in terms of simple graphs. The modeling framework built upon the formal model allows one to describe a problem with asserted facts, rules representing implicit knowledge about the do-main, validity constraints and rules transforming the world. A prototype implementing this framework has been built upon the tool CoGITaNT. It has been used to test our modelization of the room allocation problem.

The ImageCLEF 2013 Plant Identification Task

International audienceThe ImageCLEF's plant identification task provides a testbed for a system-oriented evaluation of plant identification about 250 species trees and herbaceous plants based on detailed views of leaves, flowers, fruits, stems and bark or some entire views of the plants. Two types of image content are considered: SheetAsBackgroud which contains only leaves in a front of a generally white uniform background, and NaturalBackground which contains the 5 kinds of detailed views with unconstrained conditions, directly photographed on the plant. The main originality of this data is that it was specifically built through a citizen sciences initiative conducted by Tela Botanica, a French social network of amateur and expert botanists. This makes the task closer to the conditions of a real-world application. This overview presents more precisely the resources and assessments of task, summarizes the retrieval approaches employed by the participating groups, and provides an analysis of the main evaluation results. With a total of twelve groups from nine countries and with a total of thirty three runs submitted, involving distinct and original methods, this third year task confirms Image Retrieval community interest for biodiversity and botany, and highlights further challenging studies in plant identification

The role of tumour necrosis factor α and NF-kB signalling in regulating neuronal survival during development

Neurons are generated in excess in the developing vertebrate peripheral nervous system, and the superfluous neurons are lost during a phase of programmed cell death that occurs shortly after they innervate their targets. Using a variety of in vitro and in vivo experimental approaches in wild type and transgenic mice, I have demonstrated that tumour necrosis factor a (TNFα) has opposite effects on neuronal survival at different stages in development. Early during the period of naturally occurring neuronal death it enhances the survival of sensory and sympathetic neurons, whereas later in development it promotes, by an autocrine mechanism, the death of neurons that fail to obtain sufficient target-derived neurotrophic factor to sustain their survival. The early survival-enhancing effect of TNFα and the survivalenhancing effect of nerve growth factor (NGF) are mediated by activation of the transcription factor NF-kB in the peripheral nervous system. However, in the case of retinal ganglion cells and motoneurons of the developing central nervous system, NF-kB appears to play a role promoting cell death during development. Finally, I demonstrated that Bad, a member of the Bcl-2 family of proteins, is required for programmed cell death of many sensory and sympathetic neurons during development. These findings show that the same extracellular and intracellular signalling proteins can exert opposite effects on neuronal survival in different locations in the nervous system and at different stages of development

Binary RDF for Scalable Publishing, Exchanging and Consumption in the Web of Data

El actual diluvio de datos está inundando la web con grandes volúmenes de datos representados en RDF, dando lugar a la denominada 'Web de Datos'. En esta tesis proponemos, en primer lugar, un estudio profundo de aquellos textos que nos permitan abordar un conocimiento global de la estructura real de los conjuntos de datos RDF, HDT, que afronta la representación eficiente de grandes volúmenes de datos RDF a través de estructuras optimizadas para su almacenamiento y transmisión en red. HDT representa efizcamente un conjunto de datos RDF a través de su división en tres componentes: la cabecera (Header), el diccionario (Dictionary) y la estructura de sentencias RDF (Triples). A continuación, nos centramos en proveer estructuras eficientes de dichos componentes, ocupando un espacio comprimido al tiempo que se permite el acceso directo a cualquier dat

Hodge Theory on Metric Spaces

Hodge theory is a beautiful synthesis of geometry, topology, and analysis, which has been developed in the setting of Riemannian manifolds. On the other hand, spaces of images, which are important in the mathematical foundations of vision and pattern recognition, do not fit this framework. This motivates us to develop a version of Hodge theory on metric spaces with a probability measure. We believe that this constitutes a step towards understanding the geometry of vision. The appendix by Anthony Baker provides a separable, compact metric space with infinite dimensional \alpha-scale homology.Comment: appendix by Anthony W. Baker, 48 pages, AMS-LaTeX. v2: final version, to appear in Foundations of Computational Mathematics. Minor changes and addition