Modernity, postmodernity and identity of jazz in Chile : The cases of the generation of 1990 and Ángel Parra

This research is about jazz in Chile in relation to modernity and identity. Final chapters focus and detach latest jazz musician s generation in 1990 decade and composer guitarist Angel Parra. An historic and sociological approach is developed, which will be useful for modernity and identity analysis, and so on post modernity and globalization. Modernity has been studied in texts of Adorno, Baudrillard, Brünner, García Canclini, Habermas and Jameson. Identity has been studied in texts of Aharonián, Cordúa, Garretón, Gissi, Larraín and others. Chapter 3 is about Latin-American musicology and jazz investigations, in relation to approach developed in chapter 2. Chapters 4 and 5 are about history of jazz in Chile until beginning of XXI century. Chapter 6 focuses in Ángel Parra Orrego. Conclusions of this investigation detach the modernist mechanical that has conducted jazz development in Chile, which in Ángel Parra´s case has been overcame by a post modernist behaviour. This behaviour has solved in a creative way, subjects like modernity and identity in jazz practice in a Latin-American country.

Fast in-memory XPath search using compressed indexes

A large fraction of an XML document typically consists of text data. The XPath query language allows text search via the equal, contains, and starts-with predicates. Such predicates can be efficiently implemented using a compressed self-index of the document's text nodes. Most queries, however, contain some parts querying the text of the document, plus some parts querying the tree structure. It is therefore a challenge to choose an appropriate evaluation order for a given query, which optimally leverages the execution speeds of the text and tree indexes. Here the SXSI system is introduced. It stores the tree structure of an XML document using a bit array of opening and closing brackets plus a sequence of labels, and stores the text nodes of the document using a global compressed self-index. On top of these indexes sits an XPath query engine that is based on tree automata. The engine uses fast counting queries of the text index in order to dynamically determine whether to evaluate top-down or bottom-up with respect to the tree structure. The resulting system has several advantages over existing systems: (1) on pure tree queries (without text search) such as the XPathMark queries, the SXSI system performs on par or better than the fastest known systems MonetDB and Qizx, (2) on queries that use text search, SXSI outperforms the existing systems by 1-3 orders of magnitude (depending on the size of the result set), and (3) with respect to memory consumption, SXSI outperforms all other systems for counting-only queries.

Storage and retrieval of individual genomes

A repetitive sequence collection is one where portions of a base sequence of length n are repeated many times with small variations, forming a collection of total length N. Examples of such collections are version control data and genome sequences of individuals, where the differences can be expressed by lists of basic edit operations. Flexible and efficient data analysis on a such typically huge collection is plausible using suffix trees. However, suffix tree occupies O(N log N) bits, which very soon inhibits in-memory analyses. Recent advances in full-text self-indexing reduce the space of suffix tree to O(N log σ) bits, where σ is the alphabet size. In practice, the space reduction is more than 10-fold, for example on suffix tree of Human Genome. However, this reduction factor remains constant when more sequences are added to the collection. We develop a new family of self-indexes suited for the repetitive sequence collection setting. Their expected space requirement depends only on the length n of the base sequence and the number s of variations in its repeated copies. That is, the space reduction factor is no longer constant, but depends on N / n. We believe the structures developed in this work will provide a fundamental basis for storage and retrieval of individual genomes as they become available due to rapid progress in the sequencing technologies.