The impact of context on pattern category learning and representation

Context traditionally has been regarded in vision research as a determinant for the interpretation of sensory information on the basis of previously acquired knowledge. Here we propose a novel, complementary perspective by showing that context also specifically affects visual category learning. In two experiments involving sets of Compound Gabor patterns we explored how context, as given by the stimulus set to be learned, affects the internal representation of pattern categories. In Experiment 1, we changed the (local) context of the individual signal classes by changing the configuration of the learning set. In Experiment 2, we varied the (global) context of a fixed class configuration by changing the degree of signal accentuation. Generalization performance was assessed in terms of the ability to recognize contrast-inverted versions of the learning patterns. Both contextual variations yielded distinct effects on learning and generalization thus indicating a change in internal category representation. Computer simulations suggest that the latter is related to changes in the set of attributes underlying the production rules of the categories. The implications of these findings for phenomena of contrast (in)variance in visual perception are discussed.

Analysis and representation of statistical performance of JPEG2000 encoded image over wireless channels

JPEG2000 is a new coming image standard. In this paper we analyze the performance of error resilience tools in JPEG2000, and present an analytical model to estimate the quality of JPEG2000 encoded image transmitted over wireless channels. The effectiveness of the analytical model is validated by simulation results. Furthermore, analytical model is utilized by the base station to design efficient unequally error protection schemes for JPEG2000 transmission. In the design, a utility function is denned to make a tradeoff between the image quality and the cost for transmitting the image over wireless channel. © 2002 IEEE.

The translation of cell-based therapies:clinical landscape and manufacturing challenges

Cell-based therapies have the potential to make a large contribution toward currently unmet patient need and thus effective manufacture of these products is essential. Many challenges must be overcome before this can become a reality and a better definition of the manufacturing requirements for cell-based products must be obtained. The aim of this study is to inform industry and academia of current cell-based therapy clinical development and to identify gaps in their manufacturing requirements. A total of 1342 active cell-based therapy clinical trials have been identified and characterized based on cell type, target indication and trial phase. Multiple technologies have been assessed for the manufacture of these cell types in order to facilitate product translation and future process development.

Women, power and politics

This is major new introduction to women's political involvement and role in the liberal democratic world drawing examples from a wide range of countries to illustrate key common features and divergences. Stevens assesses women's participation and representation in government, parliaments and at the grassroots. Does gender make a difference?

Representing others:translation, ethnography and museum

Cultural anthropology has always been dependent on translation as a textual practice, and it has often used 'translation' as a metaphor to describe ethnography's processes of interpretation and cross-cultural comparison. Questions of intelligibility and representation are central to both translation studies and ethnographic writing - as are the dilemmas of cultural distance or proximity, exoticism or appropriation. Similarly, recent work in museum studies discusses problems of representation that are raised by ethnographic museums as multimedia 'translations'. However, as yet there has been remarkably little interdisciplinary exchange: neither has translation studies kept up with the sophistication of anthropology's investigations of meaning, representation and 'culture' itself, nor have anthropology and museum studies often looked to translation studies for analyses of language difference or concrete methods of tracing translation practices.

Description and critical appraisal of principal components analysis (PCA) methodology applied to pulsed-field gel electrophoresis profiles of methicillin-resistant Staphylococcus aureus isolates

Principal components analysis (PCA) has been described for over 50 years; however, it is rarely applied to the analysis of epidemiological data. In this study PCA was critically appraised in its ability to reveal relationships between pulsed-field gel electrophoresis (PFGE) profiles of methicillin- resistant Staphylococcus aureus (MRSA) in comparison to the more commonly employed cluster analysis and representation by dendrograms. The PFGE type following SmaI chromosomal digest was determined for 44 multidrug-resistant hospital-acquired methicillin-resistant S. aureus (MR-HA-MRSA) isolates, two multidrug-resistant community-acquired MRSA (MR-CA-MRSA), 50 hospital-acquired MRSA (HA-MRSA) isolates (from the University Hospital Birmingham, NHS Trust, UK) and 34 community-acquired MRSA (CA-MRSA) isolates (from general practitioners in Birmingham, UK). Strain relatedness was determined using Dice band-matching with UPGMA clustering and PCA. The results indicated that PCA revealed relationships between MRSA strains, which were more strongly correlated with known epidemiology, most likely because, unlike cluster analysis, PCA does not have the constraint of generating a hierarchic classification. In addition, PCA provides the opportunity for further analysis to identify key polymorphic bands within complex genotypic profiles, which is not always possible with dendrograms. Here we provide a detailed description of a PCA method for the analysis of PFGE profiles to complement further the epidemiological study of infectious disease. © 2005 Elsevier B.V. All rights reserved.

The social media paradox:an intersection with freedom of expression and the criminal law

This article begins by setting out the human rights provisions that apply to social media expression. It then provides insight into the part social media plays within our society by analysing the social media landscape and how it facilitates a ‘purer’ form of expression. The social media paradox is explored through the lens of current societal issues and concerns regarding the use of social media and how these have manifested into litigation. It concludes by analysing the tension that the application of an array of criminal legislation and jurisprudence has created with freedom of expression, and whether this can successfully mitigated by the Director of Public Prosecution’s Interim Guidelines.

Plant closures, precariousness and policy responses:revisiting MG Rover 10 years on

With automotive plants being closed in Australia and western Europe, this article reflects on the employment status of ex-MG Rover (MGR) workers following the closure of the Longbridge plant in 2005. In particular, it draws on Standing's typology of labour market insecurity and uses a mixed-methods approach including an analysis of a longitudinal survey of some 200 ex-MGR workers, and in-depth interviews with ex-workers and policy-makers. While the policy response to the closure saw significant successes in terms of the great majority of workers successfully adjusting into re-employment, and with positive findings in terms of re-training and education, the paper finds significant challenges in terms of security of employment, income, job quality and representation at work years after closure. In particular, the paper posits that the general lack of attention to employment security at the macrolevel effectively undermined elements of a positive policy response over the longer run. This in turn suggests longer-term policy measures are required to address aspects of precariousness at work.