Transformational-transactional leadership and upward influence:the role of Relative Leader-Member Exchanges (RLMX) and Perceived Organizational Support (POS)

By utilizing the resource theory of social exchange (Foa & Foa, 1974), we attempted to cast light on the dynamics of the relationship between transformational-transactional leadership and employees' upward influence tactics. Using data collected in two time points (N=200, 1. year apart), we found perceptions of transformational leadership (Time 1) to be positively related to the use of soft and rational upward influence tactics (Time 2) whereas transactional leadership (Time 1) was positively related to the use of soft and hard upward influence tactics (Time 2). We also found support for a 3-way interaction between transformational-transactional leadership, relative Leader Member Exchanges (RLMX) and Perceived Organizational Support (POS) on employees' upward influence tactics. Specifically, in resource-constrained conditions (low RLMX and low POS), employees were likely to use soft tactics to influence a manager they perceived as transformational to a greater extent than in resource-munificent conditions. They were also likely to employ higher levels of soft and hard tactics to influence a transactional manager in resource-constrained rather than in resource-munificent conditions. © 2012 Elsevier Inc.

Identification of the HLA-DM/HLA-DR interface

Human leukocyte antigen (HLA)-DM is a critical participant in antigen presentation that catalyzes the dissociation of the Class II-associated Invariant chain-derived Peptide (CLIP) from the major histocompatibility complex (MHC) Class II molecules. There is competition amongst peptides for access to an MHC Class II groove and it has been hypothesised that DM functions as a 'peptide editor' that catalyzes the replacement of one peptide for another within the groove. It is established that the DM catalyst interacts directly with the MHC Class II but the precise location of the interface is unknown. Here, we combine previously described mutational data with molecular docking and energy minimisation simulations to identify a putative interaction site of >4000A2 which agrees with known point mutational data for both the DR and DM molecule. The docked structure is validated by comparison with experimental data and previously determined properties of protein-protein interfaces. A possible dissociation mechanism is suggested by the presence of an acidic cluster near the N terminus of the bound peptide.

Watermark-only security attack on DM-QIM watermarking:vulnerability to guided key guessing

This paper addresses the security of a specific class of common watermarking methods based on Dither modulation-quantisation index modulation (DM-QIM) and focusing on watermark-only attacks (WOA). The vulnerabilities of and probable attacks on lattice structure based watermark embedding methods have been presented in the literature. DM-QIM is one of the best known lattice structure based watermarking techniques. In this paper, the authors discuss a watermark-only attack scenario (the attacker has access to a single watermarked content only). In the literature it is an assumption that DM-QIM methods are secure to WOA. However, the authors show that the DM-QIM based embedding method is vulnerable against a guided key guessing attack by exploiting subtle statistical regularities in the feature space embeddings for time series and images. Using a distribution-free algorithm, this paper presents an analysis of the attack and numerical results for multiple examples of image and time series data.

Watermark-only security attack on DM-QIM watermarking:vulnerability to guided key guessing

This paper addresses the security of a specific class of common watermarking methods based on Dither modulation-quantisation index modulation (DM-QIM) and focusing on watermark-only attacks (WOA). The vulnerabilities of and probable attacks on lattice structure based watermark embedding methods have been presented in the literature. DM-QIM is one of the best known lattice structure based watermarking techniques. In this paper, the authors discuss a watermark-only attack scenario (the attacker has access to a single watermarked content only). In the literature it is an assumption that DM-QIM methods are secure to WOA. However, the authors show that the DM-QIM based embedding method is vulnerable against a guided key guessing attack by exploiting subtle statistical regularities in the feature space embeddings for time series and images. Using a distribution-free algorithm, this paper presents an analysis of the attack and numerical results for multiple examples of image and time series data.

THOMAS NIEHR AND KARIN BÖKE (eds), Einwanderungsdiskurse. Vergleichende diskurslinguistische Studien. [Immigration Discourses: Comparative Discourse Studies.] Opladen: Westdeutscher Verlag, 2000. 241 pp. DM 56.00 (pbk). ISBN 3–5311–3307–1

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