Mobile qualified electronic signatures for secure mobile brokerage

Despite a legal framework being in place for several years, the market share of qualified electronic signatures is disappointingly low. Mobile Signatures provide a new and promising opportunity for the deployment of an infrastructure for qualified electronic signatures. We that SIM-based signatures are the most secure and convenient solution. However, using the SIM-card as a secure signature creation device (SSCD) raises new challenges, because it would contain the user’s private key as well as the subscriber identification. Combining both functions in one card raises the question who will have the control over the keys and certificates. We propose a protocol called Certification on Demand (COD) that separates certification services from subscriber identification information and allows consumers to choose their appropriate certification services and service providers based on their needs. This infrastructure could be used to enable secure mobile brokerage services that can ommit the necessity of TAN lists and therefore allow a better integration of information and transaction services

An Outline of a Neural Architecture for Unified Visual Contrast and Brightness Perception

In this contribution a neural architecture is proposed that serves as a framework for further empirical as well as modeling investigations into a unified theory for contrast, contour and lnightncss perception. The computational mechanisms utilize a center-surround antagonism based on shunting interactions which allow to multiples contrast. as well as luminance data. As a key new feature, this data is demultiplexed at a later stage into segrcgated processing streams that signal both local contrast information of each polarity, and a scaled, low-pass filted and compressed version of the luminance information respectively. In correspondence with recent findings about the major processing channels in the primary visual system, the ON and OFF contrast channels feed into a subsystem for contrast processing, perceptual organization, and grouping (boundary contour system, BCS). The activity in the Segregated luminance path, however, is hypothesized to he contrast enhanced via shunting interaction, utilized hy the coc~xisLing contrast. channels. Following Grossbergs FACADE architecture, it is suggested that activity generated in the BCS acts as a modulation mechanism that controls the local diffusion coefficients for lateral activity spreading within the segregated brightness&darkness (B&D) channel. A three stage process is suggested for brightness reconstruction and filling-in. Based on the segregation of ON and OFF contrast information and basic neural principles such as divergence, convergence, and pooling, the nrodel accounts for the linear response properties of odd and even symetric simple and complex cells in VI. Theoretical analysis of the network's function at various stages of processing, provides a framework for quantitative studies referring to available data on visual perception.German Ministry of Research and Technology (413-5839-01 1N 101 C/1

Pro-inflammatory signaling by IL-10 and IL-22: bad habit stirred up by interferons?

Interleukin (IL)-10 and IL-22 are key members of the IL-10 cytokine family that share characteristic properties such as defined structural features, usage of IL-10R2 as one receptor chain, and activation of signal transducer and activator of transcription (STAT)-3 as dominant signaling mode. IL-10, formerly known as cytokine synthesis inhibitory factor, is key to deactivation of monocytes/macrophages and dendritic cells. Accordingly, pre-clinical studies document its anti-inflammatory capacity. However, the outcome of clinical trials assessing the therapeutic potential of IL-10 in prototypic inflammatory disorders has been disappointing. In contrast to IL-10, IL-22 acts primarily on non-leukocytic cells, in particular epithelial cells of intestine, skin, liver, and lung. STAT3-driven proliferation, anti-apoptosis, and anti-microbial tissue protection is regarded a principal function of IL-22 at host/environment interfaces. In this hypothesis article, hidden/underappreciated pro-inflammatory characteristics of IL-10 and IL-22 are outlined and related to cellular priming by type I interferon. It is tempting to speculate that an inherent inflammatory potential of IL-10 and IL-22 confines their usage in tissue protective therapy and beyond that determines in some patients efficacy of type I interferon treatment

Taking the heterogeneity of citizens into account: flood risk communication in coastal cities – a case study of Bremen

The likely manifestations of climate change like flood hazards are prominent topics in public communication. This can be shown by media analysis and questionnaire data. However, in the case of flood risks an information gap remains resulting in misinformed citizens who probably will not perform the necessary protective actions when an emergency occurs. This paper examines more closely a newly developed approach to flood risk communication that takes the heterogeneity of citizens into account and aims to close this gap. The heterogeneity is analysed on the meso level regarding differences in residential situation as well as on the micro level with respect to risk perception and protective actions. Using the city of Bremen as a case study, empirical data from n=831 respondents were used to identify Action Types representing different states of readiness for protective actions in view of flood risks. These subpopulations can be provided with specific information to meet their heterogeneous needs for risk communication. A prototype of a computer-based information system is described that can produce and pass on such tailored information. However, such an approach to risk communication has to be complemented by meso level analysis which takes the social diversity of subpopulations into account. Social vulnerability is the crucial concept for understanding the distribution of resources and capacities among different social groups. We therefore recommend putting forums and organisations into place that can mediate between the state and its citizens

Skid resistance and durability of coated and uncoated concrete floors in dairy cattle buildings

Passageways in cattle buildings should provide durable and non-slippery surface to allow cattle an unrestrained locomotion and expression of behaviour. In order to evaluate walking areas fo cattle buildings and their grip or skid resistance, measures with Skid Resistance Tester to obtain SRT-values were performed on sevreal dairy farms in Germany

Uniform convergence rates and uniform adaptive estimation in mixtures of regressions

In this thesis, we develop theoretical tools to examine estimators in non-parametric regression models in regard of uniform convergence rates and uniform adaptivity with respect to the smoothness of the parameter functions. Subsequently, those are applied to non-parametric regression models with Hölder-smooth parameter functions. One model is a mixture of Gaussian regressions and the other model is a mixture model with two components and an unspecified symmetric error distribution

Thermocycling experiments with the three-dimensional Ising spin glass model

A characteristic feature of the non--equilibrium dynamics of real spin glasses at low temperatures are strong aging effects. These phenomena can be manipulated by changing the external parameters in various ways: a thermo-cycling experiment consists for instance of a short heat pulse during the waiting time, by which the relaxation might be strongly affected. Results of numerical experiments of this kind, performed via Monte Carlo simulations of the three dimensional Ising spin glass model, are presented. The theoretical implications are discussed and the scenario found is compared with the experimental situation.Comment: LaTeX 13 pages (+6 figures upon request), THP11-9