Document Word Clouds: Visualising Web Documents as Tag Clouds to Aid Users in Relevance Decisions

Περιέχει το πλήρες κείμενοInformation Retrieval systems spend a great effort on determining the significant terms in a document. When, instead, a user is looking at a document he cannot benefit from such information. He has to read the text to understand which words are important. In this paper we take a look at the idea of enhancing the perception of web documents with visualisation techniques borrowed from the tag clouds of Web 2.0. Highlighting the important words in a document by using a larger font size allows to get a quick impression of the relevant concepts in a text. As this process does not depend on a user query it can also be used for explorative search. A user study showed, that already simple TF-IDF values used as notion of word importance helped the users to decide quicker, whether or not a document is relevant to a topic

Deletion of the unique gene encoding a typical histone H1 has no apparent phenotype in Aspergillus nidulans

We have cloned the H1 histone gene (hhoA) of Aspergillus nidulans. This single-copy gene codes for a typical linker histone with one central globular domain. The open reading frame is interrupted by six introns. The position of the first intron is identical to that of introns found in some plant histones. An H1–GFP fusion shows exclusive nuclear localization, whereas chromosomal localization can be observed during condensation at mitosis. Surprisingly, the deletion of hhoA results in no obvious phenotype. The nucleosomal repeat length and susceptibility to micrococcal nuclease digestion of A. nidulans chromatin are unchanged in the deleted strain. The nucleosomal organization of a number of promoters, including in particular the strictly regulated niiA-niaD bidirectional promoter is not affected.This work was supported by EC grant BIO2-CT93-0147, the CNRS and the Université Paris Sud. M.I.M-P. has been the recipient of CE fellowship BIO-CT-94-8102 and a fellowship from the Fondation pour la Recherche Médicale. R.G. has been the recipient of CE fellowship BIO4-CT-96-5010Peer reviewe