hITeQ: A new workflow-based computing environment for streamlining discovery. Application in materials science

[EN] This paper presents the implementation of the recent methodology called Adaptable Time Warping (ATW) for the automatic identification of mixture of crystallographic phases from powder X-ray diffraction data, inside the framework of a new integrative platform named hITeQ. The methodology is encapsulated into a so-called workflow, and we explore the benefits of such an environment for streamlining discovery in R&D. Beside the fact that ATW successfully identifies and classifies crystalline phases from powder XRD for the very complicated case of zeolite ITQ-33 for which has been employed a high throughput synthesis process, we stress on the numerous difficulties encountered by academic laboratories and companies when facing the integration of new software or techniques. It is shown how an integrative approach provides a real asset in terms of cost, efficiency, and speed due to a unique environment that supports well-defined and reusable processes, improves knowledge management, and handles properly multi-disciplinary teamwork, and disparate data structures and protocols.EU Commission FP6 (TOPCOMBI Project) is gratefully acknowledged.Baumes, LA.; Jiménez Serrano, S.; Corma Canós, A. (2011). hITeQ: A new workflow-based computing environment for streamlining discovery. Application in materials science. Catalysis Today. 159(1):126-137. doi:10.1016/j.cattod.2010.03.067S126137159

Benchmarks for testing community detection algorithms on directed and weighted graphs with overlapping communities

Many complex networks display a mesoscopic structure with groups of nodes sharing many links with the other nodes in their group and comparatively few with nodes of different groups. This feature is known as community structure and encodes precious information about the organization and the function of the nodes. Many algorithms have been proposed but it is not yet clear how they should be tested. Recently we have proposed a general class of undirected and unweighted benchmark graphs, with heterogenous distributions of node degree and community size. An increasing attention has been recently devoted to develop algorithms able to consider the direction and the weight of the links, which require suitable benchmark graphs for testing. In this paper we extend the basic ideas behind our previous benchmark to generate directed and weighted networks with built-in community structure. We also consider the possibility that nodes belong to more communities, a feature occurring in real systems, like, e. g., social networks. As a practical application, we show how modularity optimization performs on our new benchmark.Comment: 9 pages, 13 figures. Final version published in Physical Review E. The code to create the benchmark graphs can be freely downloaded from http://santo.fortunato.googlepages.com/inthepress

Seeding for pervasively overlapping communities

In some social and biological networks, the majority of nodes belong to multiple communities. It has recently been shown that a number of the algorithms that are designed to detect overlapping communities do not perform well in such highly overlapping settings. Here, we consider one class of these algorithms, those which optimize a local fitness measure, typically by using a greedy heuristic to expand a seed into a community. We perform synthetic benchmarks which indicate that an appropriate seeding strategy becomes increasingly important as the extent of community overlap increases. We find that distinct cliques provide the best seeds. We find further support for this seeding strategy with benchmarks on a Facebook network and the yeast interactome.Comment: 8 Page

Changes in aromatic characteristics of loureiro and alvarinho wines during maturation

Changes in volatiles during maturation in bottles of monovarietal Vinhos Verdes wines from Loureiro and Alvarinho grape varieties, were followed by chemical and sensory analyses. Young wines and wines matured for 8 and 20 months were studied. The volatiles were determined by gas chromatography– mass spectrometry (GC-MS) after extraction on XAD-2 resin. Straight chain fatty acid ethyl esters and acetates of fusel alcohols decreased quicker for Loureiro wine, while the increase in ethyl esters of branched fatty acids was similar for both varieties. Linalool, Ho-trienol, a-terpineol and b-damascenone could be used to differentiate between each variety. However, linalool decreased to negligible values after 20 months of maturation. b-Damascenone decreased but remained high enough to be useful for differentiating each variety. Sensory analysis indicated a decrease of tropical fruit and tree fruit characters with conservation time for Alvarinho wine, and the opposite for Loureiro; moreover, citrus fruit character decreased in both varietiesCentre of Biological Engineering of Universidade do Minho (CEB-UM); Estação Vitivinícola Amândio Galhano (EVAG); Solar de Serrade; Comissão de Viticultura da Região dos Vinhos Verdes

Soil and climatic influence on the free and glycosidically bound volatiles of grapes from two white varieties from vinhos verdes region

The Vinhos Verdes Region is situated in the northwest of Portugal. The Atlantic Ocean and the relief markedly influence the climate. This region is in Viticultural Zone C I a) of the Winegrowing Regions of the European Communities. The produced wine is unique and its specific characteristics are mainly due to the climate and soil. The white Vinho Verde is softly alcoholic, with a delicate, fresh and fruity bouquet. In this work we investigated the influence of the climate and the soil on the volatile compounds of grapes from two autochthonous white grape varieties, Alvarinho and Loureiro, in two sub-regions for each one of them (Alvarinho - Monção and Lima; Loureiro - Lima and Cávado). The research was carried out during three years: 1996, 1997 and 1998. We found out that the global characteristics of the grapes from the two varieties depend on the harvest factor (climate) rather than on the sub-region where the vine is planted. The characteristics of the soil have an even lesser influence on the variableness of the samples, although the Alvarinho variety picked in the Lima sub-region seems to have different characteristics

Différentiation des cépages portugais Loureiro et Alvarinho basée sur la composition monoterpénique libre

IBQF; Com. Vit. Região Vinhos Verdes (EVAG); Adega C.R. Monção; Casa da Tapada