A Concept for Attribute-Based Authorization on D-Grid Resources

In Germany's D-Grid project numerous Grid communities are working together to provide a common overarching Grid infrastructure. The major aims of D-Grid are the integration of existing Grid deployments and their interoperability. The challenge lies in the heterogeneity of the current implementations: three Grid middleware stacks and different Virtual Organization management approaches have to be embraced to achieve the intended goals. In this article we focus oil the implementation of an attribute-based authorization infrastructure that not only leverages the well-known VO attributes but also campus attributes managed by a Shibboleth federation

Learning to Predict Image-based Rendering Artifacts with Respect to a Hidden Reference Image

Image metrics predict the perceived per-pixel difference between a reference image and its degraded (e. g., re-rendered) version. In several important applications, the reference image is not available and image metrics cannot be applied. We devise a neural network architecture and training procedure that allows predicting the MSE, SSIM or VGG16 image difference from the distorted image alone while the reference is not observed. This is enabled by two insights: The first is to inject sufficiently many un-distorted natural image patches, which can be found in arbitrary amounts and are known to have no perceivable difference to themselves. This avoids false positives. The second is to balance the learning, where it is carefully made sure that all image errors are equally likely, avoiding false negatives. Surprisingly, we observe, that the resulting no-reference metric, subjectively, can even perform better than the reference-based one, as it had to become robust against mis-alignments. We evaluate the effectiveness of our approach in an image-based rendering context, both quantitatively and qualitatively. Finally, we demonstrate two applications which reduce light field capture time and provide guidance for interactive depth adjustment.Comment: 13 pages, 11 figure

A comprehensive evaluation of rhythm monitoring strategies for the detection of atrial fibrillation recurrence: insights from 647 continuously monitored patients and implications for monitoring after therapeutic interventions

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Modulation of Calcitonin Secretion by Modification of Calcium Channels?

Voltage-dependent calcium channels (VDCC) regulating Ca++ influx through the cellular plasma membrane play a major role in the Ca++ -induced calcitonin (CT) secretion. Using rat C-cells (rMTC 6-23 cell line), we have studied the effect of repetitive stimulation by either Ca++ (2 mM) or glucagon (10 μM) or epinephrine (10 μM) on CT secretion. Following a Ca++ -induced initial rise, CT release declined to basal levels after about four hours despite high Ca++ ; addition of 10 μM glucagon to the Ca++ desensitized C-cells yielded the normal stimulatory effect of glucagon on CT release. Repetitive stimulation with glucagon showed a constant stimulatory action over an eight-hour period. In contrast, repetitive stimulation with 10 μM epinephrine caused an initial rise followed by a gradual decline of CT release over six hours. The observed desensitization of Ca++ -induced CT secretion may be due to a modification of VDCC in C-cells. Whether or not the desensitization of epinephrine-induced CT release occurs independently of the regulation of VDCC remains unclear

Examining the Moderating Effects of Organizational Identification between Human Resource Practices and Employee Turnover Intentions in Indian Hospitality Industry

This paper presents an employee turnover intention model, which examines the effects of frontline employees’ perceptions of human resource practices (recruitment, selection, training, career growth opportunities, performance appraisal and compensation) on employee turnover intention in Indian hospitality firms. Using this model as a framework, the role of organizational identification in the aforementioned relationship is explored. Hierarchical linear regression analyses demonstrated that selection and compensation practices have significant effects on employee turnover intention. Organizational identification moderates the relationship between selection practices and employee turnover intention. The paper concludes with implications for managers in hospitality industry and some future research directions

Differentiation Restricted Endocytosis of Cell Penetrating Peptides in MDCK Cells Corresponds with Activities of Rho-GTPases

Purpose: Cellular entry of biomacromolecules is restricted by the barrier function of cell membranes. Tethering such molecules to cell penetrating peptides (CPPs) that can translocate cell membranes has opened new horizons in biomedical research. Here, we investigate the cellular internalization of hCT(9-32)-br, a human calcitonin derived branched CPP, and SAP, a γ-zein related sequence. Methods: Internalization of fluorescence labelled CPPs was performed with both proliferating and confluent MDCK cells by means of confocal laser scanning microscopy (CLSM) and fluorescence activated cell sorting (FACS) using appropriate controls. Internalization was further elaborated in an inflammatory, IFN-γ/TNF-αa induced confluent MDCK model mimicking inflammatory epithelial pathologies. Activities of active form Rho-GTPases (Rho-A and Rac-1) in proliferating and confluent MDCK cells were monitored by pull-down assay and Western blot analysis. Results: We observed marked endocytic uptake of the peptides into proliferating MDCK by a process suggesting both lipid rafts and clathrin-coated pits. In confluent MDCK, however, we noted a massive but compound-unspecific slow-down of endocytosis. This corresponded with a down-regulation of endocytosis by Rho-GTPases, previously identified to be intimately involved in endocytic traffic. In fact, we found endocytic internalization to relate with active Rho-A; vice versa, MDCK cell density, degree of cellular differentiation and endocytic slow-down were found to relate with active Rac-1. To our knowledge, this is the first study to cast light on the previously observed differentiation restricted internalization of CPPs into epithelial cell models. In the inflammatory IFN-γ/TNF-αa induced confluent MDCK model mimicking inflammatory epithelial pathologies, CPP internalization was enhanced in a cytokine concentration-dependent way resulting in maximum enhancement rates of up to 90%. We suggest a cytokine induced redistribution of lipid rafts in confluent MDCK to cause this enhancement. Conclusion: Our findings emphasize the significance of differentiated cell models in the study of CPP internalization and point towards inflammatory epithelial pathologies as potential niche for the application of CPPs for cellular deliver

09131 Abstracts Collection -- Service Level Agreements in Grids

From 22.03. to 27.03.09, the Dagstuhl Seminar 09131 ``Service Level Agreements in Grids \u27\u27 was held in Schloss Dagstuhl~--~Leibniz Center for Informatics. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available

Die Neupositionierung des Wealth Management in der Schweiz : Entwicklungen und ihre Auswirkungen auf die Soll-Kompetenzen in der Kundenberatung

StudieDie vorliegende Studie zeichnet ein umfassendes Bild zur Neupositionierung des Wealth Management in der Schweiz. Sie stützt sich dabei namentlich auf eine Online-Befragung von in der Kundenberatung tätigen Personen und auf persönliche Interviews mit Führungskräften von Schweizer Banken ab. Dabei stand insgesamt die Frage im Zentrum, wie sich die Rahmenbedingungen für die Beratung von Privatkunden im Wealth Management verändern werden und was dies für die zukünftigen Soll-Kompetenzen von Kundenberatern und den Aus- und Weiterbildungsbedarf bedeutet

Predicting long-term outcome after acute ischemic stroke: a simple index works in patients from controlled clinical trials

Background and Purpose—An early and reliable prognosis for recovery in stroke patients is important for initiation of individual treatment and for informing patients and relatives. We recently developed and validated models for predicting survival and functional independence within 3 months after acute stroke, based on age and the National Institutes of Health Stroke Scale score assessed within 6 hours after stroke. Herein we demonstrate the applicability of our models in an independent sample of patients from controlled clinical trials. Methods—The prognostic models were used to predict survival and functional recovery in 5419 patients from the Virtual International Stroke Trials Archive (VISTA). Furthermore, we tried to improve the accuracy by adapting intercepts and estimating new model parameters. Results—The original models were able to correctly classify 70.4% (survival) and 72.9% (functional recovery) of patients. Because the prediction was slightly pessimistic for patients in the controlled trials, adapting the intercept improved the accuracy to 74.8% (survival) and 74.0% (functional recovery). Novel estimation of parameters, however, yielded no relevant further improvement. Conclusions—For acute ischemic stroke patients included in controlled trials, our easy-to-apply prognostic models based on age and National Institutes of Health Stroke Scale score correctly predicted survival and functional recovery after 3 months. Furthermore, a simple adaptation helps to adjust for a different prognosis and is recommended if a large data set is available. (Stroke. 2008;39:000-000.

Polymorphisms of the NADPH Oxidase p22phox Gene in a Caucasian Population with Intracranial Aneurysms

Background: Vascular remodeling generated by reactive oxygen species contributes to aneurysm formation. The NADPH oxidase system is a major source of superoxide anion not only in phagocytes, but also in endothelial and vascular smooth muscle cells. Polymorphisms of p22phox, an essential component of the NADPH oxidase system, are found to be associated with atherosclerosis, while a recent study found a significant association between the 214C>T polymorphism and the occurrence of ischemic cerebrovascular disease. We conducted a case-control study to investigate the relationship of five polymorphisms of the p22phox gene and the occurrence of cerebral aneurysms. Methods: The study population consisted of 113 patients with intracranial aneurysms and 53 control subjects. The 214C>T polymorphism was investigated by restriction fragment length polymorphism analysis, while polymorphisms 381T>C, 480G>A, 521C>T, and *24A>G were analyzed by direct sequencing of exon 6 and adjacent intronic sequences. Results: The analysis of a primary study sample comprising 35 cases and 28 controls failed to show a significant association between any of the five polymorphisms and the occurrence of intracranial aneurysms using both allele frequencies and genotypes (all nominal p > 0.05). Although there was a deviation from Hardy-Weinberg equilibrium in cases at the 521C>T locus (nominal p T, 521C>T, and *24A>G); haplotype frequencies in cases and controls were not significantly different. Conclusion: Although polymorphisms of the p22phox gene located in the coding region and the 3′-untranslated region were reported to be associated with atherosclerosis and cerebrovascular disease, our data provide evidence that there is no association between these polymorphisms and the occurrence of cerebral aneurysms in Caucasians.Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich