14 research outputs found

    Characteristics of the nuclear (18S, 5.8S, 28S and 5S) and mitochondrial (12S and 16S) rRNA genes of Apis mellifera (Insecta: Hymenoptera): structure, organization, and retrotransposable elements

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    As an accompanying manuscript to the release of the honey bee genome, we report the entire sequence of the nuclear (18S, 5.8S, 28S and 5S) and mitochondrial (12S and 16S) ribosomal RNA (rRNA)-encoding gene sequences (rDNA) and related internally and externally transcribed spacer regions of Apis mellifera (Insecta: Hymenoptera: Apocrita). Additionally, we predict secondary structures for the mature rRNA molecules based on comparative sequence analyses with other arthropod taxa and reference to recently published crystal structures of the ribosome. In general, the structures of honey bee rRNAs are in agreement with previously predicted rRNA models from other arthropods in core regions of the rRNA, with little additional expansion in non-conserved regions. Our multiple sequence alignments are made available on several public databases and provide a preliminary establishment of a global structural model of all rRNAs from the insects. Additionally, we provide conserved stretches of sequences flanking the rDNA cistrons that comprise the externally transcribed spacer regions (ETS) and part of the intergenic spacer region (IGS), including several repetitive motifs. Finally, we report the occurrence of retrotransposition in the nuclear large subunit rDNA, as R2 elements are present in the usual insertion points found in other arthropods. Interestingly, functional R1 elements usually present in the genomes of insects were not detected in the honey bee rRNA genes. The reverse transcriptase products of the R2 elements are deduced from their putative open reading frames and structurally aligned with those from another hymenopteran insect, the jewel wasp Nasonia (Pteromalidae). Stretches of conserved amino acids shared between Apis and Nasonia are illustrated and serve as potential sites for primer design, as target amplicons within these R2 elements may serve as novel phylogenetic markers for Hymenoptera. Given the impending completion of the sequencing of the Nasonia genome, we expect our report eventually to shed light on the evolution of the hymenopteran genome within higher insects, particularly regarding the relative maintenance of conserved rDNA genes, related variable spacer regions and retrotransposable elements

    Introduction to graph databases

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    The use of graphs in analytic environments is getting more and more widespread, with applications in many different environments like social network analysis, fraud detection, industrial management, knowledge analysis, etc. Graph databases are one important solution to consider in the management of large datasets. The course will be oriented to tackle four important aspects of graph management. First, to give a characterization of graphs and the most common operations applied on them. Second, to review the technologies for graph management and focus on the particular case of Sparksee. Third, to analyze in depth some important applications and how graphs are used to solve them. Fourth, to understand the use of benchmarking to make the requirements of the user compatible with the growth of the technologies for graph management.Peer ReviewedPostprint (published version

    Dynamic Similarity-Aware Inverted Indexing for Real-Time Entity Resolution ⋆

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    Abstract. Entity resolution is the process of identifying groups of records in a single or multiple data sources that represent the same real-world entity. It is an important tool in data de-duplication, in linking records across databases, and in matching query records against a database of existing entities. Most existing entity resolution techniques complete the resolution process offline and on static databases. However, real-world databases are often dynamic, and increasingly organizations need to resolve entities in real-time. Thus, there is a need for new techniques that facilitate working with dynamic databases in real-time. In this paper, we propose a dynamic similarity-aware inverted indexing technique (DySimII) that meets these requirements. We also propose a frequencyfiltered indexing technique where only the most frequent attribute values are indexed. We experimentally evaluate our techniques on a large realworld voter database. The results show that when the index size grows no appreciable increase is found in the average record insertion time (around 0.1 msec) and in the average query time (less than 0.1 sec). We also find that applying the frequency-filtered approach reduces the index size with only a slight drop in recall

    Some antecedents and outcomes of brand love

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    Survey research is employed to test hypotheses involving brand love, a new marketing construct that assesses satisfied consumers’ passionate emotional attachment to particular brands. Findings suggest that satisfied consumers’ love is greater for brands in product categories perceived as more hedonic (as compared with utilitarian) and for brands that offer more in terms of symbolic benefits. Brand love, in turn, is linked to higher levels of brand loyalty and positive word-of-mouth. Findings also suggest that satisfied consumers tend to be less loyal to brands in more hedonic product categories and to engage in more positive word-of-mouth about self-expressive brands. Copyright Springer Science + Business Media, Inc. 2006Satisfaction, Delight, Love, Loyalty, Word-of-mouth, Consumer-brand relationships,

    Speed and selection in the evolution of killer-cell immunoglobulin-like receptors

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    The killer-cell immunoglobulin-like receptors (KIR) form a diverse family of receptors that control the functions of natural killer cells. Sequencing of KIR from primates has revealed the unexpected extent to which this gene family has diversified mostly likely in response to pathogens and to pathogen-mediated selection of their MHC class I ligands. Human KIR diversity is now a burgeoning area for disease association studies. This review examines the evolution of KIR from a primate-centric view in order to rationalize our current knowledge of the diversity of human KIR
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