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We examine various logics that combine knowledge, awareness, and change of awareness. An agent can become aware of propositional propositions but also of other agents or of herself. The dual operation to becoming aware, forgetting, can also be modelled. Our proposals are based on a novel notion of structural similarity that we call awareness bisimulation, the obvious notion of modal similarity for structures encoding knowledge and awareness. [ABSTRACT FROM AUTHOR]

Abstract: One way of comparing knowledge representation formalisms that has attracted attention recently is in terms of representational succinctness, i.e., we can ask whether one of the formalisms allows for a more ‘economical’ encoding of information than the other. Proving that one logic is more succinct than another becomes harder when the underlying semantics is stronger. We propose to use Formula Size Games (as put forward by Adler and Immerman (2003) [1], but we present them as games for one player, called Spoiler), games that are played on two sets of models, and that directly link the length of a play in which Spoiler wins the game with the size of a formula, i.e., a formula that is true in the first set of models but false in all models of the second set. Using formula size games, we prove the following succinctness results for m-dimensional modal logic, where one has a set of indices for m modalities: (1) on general Kripke models (and also on binary trees), a definition (with ) makes the resulting logic exponentially more succinct for ; (2) several modal logics use such abbreviations , e.g., in description logics the construct corresponds to adding role disjunctions, and an epistemic interpretation of it is ‘everybody in Γ knows’. Indeed, we show that on epistemic models (i.e., -models), the logic with becomes more succinct for ; (3) the results for the logic with ‘everybody knows’ also hold for a logic with ‘somebody knows’, and (4) on epistemic models, Public Announcement Logic is exponentially more succinct than epistemic logic, if . The latter settles an open problem raised by Lutz (2006) [18]. [Copyright &y& Elsevier]

Abstract: In this paper we present a process model for developing usable cross-cultural websites. Compatible with ISO 13407, the process model documents an abstraction of the design process focusing on cultural issues in development. It provides a framework in which a variety of user-based and expert-based techniques for analysis and design are placed within the life-cycle of website development. In developing the model, we relate practical approaches to design with theories and models of culture and discuss the relevance of such theories to the practical design process. In particular we focus on four key concerns: how an audit of local website attractors can inform the design process; the concept of a cultural fingerprint to contrast websites with the cultural needs of local users; the problems associated with user evaluation; and cross-cultural team development. We then show their relation to our process model. We conclude by summarising our contribution to date within the field. [Copyright &y& Elsevier]

Potential biomarkers were identified for in vitro sensitivity to the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor gefitinib in head and neck cancer. Gefitinib sensitivity was determined in cell lines, followed by transcript profiling coupled with a novel pathway analysis approach. Eleven cell lines were highly sensitive to gefitinib (inhibitor concentration required to give 50% growth inhibition [GI50] < 1 μM), three had intermediate sensitivity (GI50 1–7 μM), and six were resistant (GI50 > 7 μM); an exploratory principal component analysis revealed a separation between the genomic profiles of sensitive and resistant cell lines. Subsequently, a hypothesis-driven analysis of Affymetrix data (Affymetrix, Inc., Santa Clara, CA, USA) revealed higher mRNA levels for E-cadherin (CDH1); transforming growth factor, alpha (TGF-α); amphiregulin (AREG); FLJ22662; EGFR; p21-activated kinase 6 (PAK6); glutathione S-transferase Pi (GSTP1); and ATP-binding cassette, subfamily C, member 5 (ABCC5) in sensitive versus resistant cell lines. A hypothesis-free analysis identified 46 gene transcripts that were strongly differentiated, seven of which had a known association with EGFR and head and neck cancer (human EGF receptor 3 [HER3], TGF-α, CDH1, EGFR, keratin 16 [KRT16], fibroblast growth factor 2 [FGF2], and cortactin [CTTN]). Polymerase chain reaction (PCR) and enzyme-linked immunoabsorbant assay analysis confirmed Affymetrix data, and EGFR gene mutation, amplification, and genomic gain correlated strongly with gefitinib sensitivity. We identified biomarkers that predict for in vitro responsiveness to gefitinib, seven of which have known association with EGFR and head and neck cancer. These in vitro predictive biomarkers may have potential utility in the clinic and warrant further investigation. [ABSTRACT FROM AUTHOR]

While the object oriented paradigm and its instantiation within programming languages such as Java has become a ubiquitous part of both the commercial and educational landscapes, its usage as a visualization technique within mathematics undergraduate programmes of study has perhaps been somewhat underestimated. By regarding the object oriented paradigm as a medium for conceptual exploration (rather than merely as a tool) the aim is to show how the close conceptual links between object orientation and certain mathematical structures such as rings and groups can be more fully realized, using a ready-made public-domain Java package. [ABSTRACT FROM AUTHOR]