Browsing by Author "Winter, R."

A challenge that IS researchers face in general is to combine the goals of generating new scientific knowledge while at the same time producing practically relevant research results, e.g., in the form of IT artefacts. To combine rigor and relevance, researchers and practitioners need to collaborate to develop and employ methods that enable both the systematic generation of scientific insights and the knowledge exchange between academia and industry. In this paper, we present the findings of a research project where we entered into an industry-academic collaboration with the financial services industry involving three software development and implementation projects. We adopted a design science research approach to accompany the project and to guide the scientific discovery process. In the course of our research process we developed an innovative research model that integrates our experiences from the research project with existing design science research mod

Background and purpose: This study aimed to characterize the time course of inflammatory parameters after acute ischemic stroke. Methods: We serially determined high sensitivity C-reactive protein (CRP), fibrinogen, and leukocyte counts at 10 time points between days I and 90 after ischemic stroke and in control subjects. Results: CRP did not significantly change, whereas fibrinogen increased after stroke. At all time points, CRP and fibrinogen were higher than in healthy control subjects, but not risk factor control subjects. The leukocyte count declined after stroke and was significantly elevated as compared to both control groups only on day 1 but not later. NIHSS levels were positively correlated with CRP and fibrinogen at all time points. Larger infarcts were associated with a higher CRP and leukocyte counts on day 90. Treatment with aspirin was associated with lower values for all three inflammatory parameters in the subacute phase after ischemia. Conclusions: The course after stroke was different between the parameters of inflammation. Only the leukocytes followed the paradigm of an acute phase response. (c) 2005 Elsevier B.V. All rights reserved.

The influence of high hydrostatic pressure on the structure and protein-protein interaction potential of highly concentrated lysozyme solutions up to about 370 mg ml(-1) was studied and analyzed using small-angle X-ray scattering in combination with a liquid-state theoretical approach. In the concentration region below 200 mg ml(-1), the interaction parameters of lysozyme solutions are affected by pressure in a nonlinear way, which is probably due to significant changes in the structural properties of bulk water, i.e., due to a solvent-mediated effect. Conversely, for higher concentrated protein solutions, where hydration layers below ∼4 water molecules are reached, the interaction potential turns rather insensitive to compression. The onset of transient (dynamic) clustering is envisaged in this concentration range. Our results also show that pressure suppresses protein nucleation, aggregation and finally crystallization in supersaturated condensed protein solutions. These findings are of importance for controlling and fine-tuning protein crystallization. Moreover, these results are also important for understanding the high stability of highly concentrated protein solutions (as they occur intracellularly) in organisms thriving under hydrostatic pressure conditions such as in the deep sea, where pressures up to the kbar-level are reached.

The influence of incorporating the polypeptide gramicidin on the lateral mobility of the monoacylglyceride monoolcin (MO) in its bicontinuous cubic lipid mesophases is studied applying static field gradient NMR. The effects of gramicidin on the topology, structure and phase behaviour of the system are characterized by small-angle x-ray scattering (SAXS) experiments. On the structural level the experiments show significant shifts in the boundaries of the various mesophases. Measurements of the translational dynamics are restricted to cubic mesophases, where the diffusion coefficients of lipid and additive are determined both by geometrical obstruction and by lipid-protein interaction effects.