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"Innovation Journalism ist die Politikberichterstattung der Zukunft" Interview mit David Nordfors
(2011)
Die dargestellte Rating-Methodik auf der Basis der Vorgehensweise von S&P erscheint bei einer grundsätzlichen Untersuchung der Ausfallwahrscheinlichkeiten von Zahlungsverpflichtungen als sachgerecht. Allerdings bedürfen die aufgezeigten Analyseschritte einer deutlichen Adjustierung der Methodik, um die unterschiedlichen Effekte einer internen und einer externen Finanzierung so herauszuarbeiten, dass nicht bereits durch die angewandte Art der Analyse Verzerrungen in den Aussagen eintreten.
2-Methyl-3-hydroxybutyryl-CoA dehydrogenase deficiency is caused by mutations in the HADH2 gene
(2003)
3D Printers as Sociable Technologies: Taking Appropriation Infrastructures to the Internet of Things
(2017)
The aim of design science research (DSR) in information systems is the user-centred creation of IT-artifacts with regard to specific social environments. For culture research in the field, which is necessary for a proper localization of IT-artifacts, models and research approaches from social sciences usually are adopted. Descriptive dimension-based culture models most commonly are applied for this purpose, which assume culture being a national phenomenon and tend to reduce it to basic values. Such models are useful for investigations in behavioural culture research because it aims to isolate, describe and explain culture-specific attitudes and characteristics within a selected society. In contrast, with the necessity to deduce concrete decisions for artifact-design, research results from DSR need to go beyond this aim. As hypothesis, this contribution generally questions the applicability of such generic culture dimensions’ models for DSR and focuses on their theoretical foundation, which goes back to Hofstede’s conceptual Onion Model of Culture. The herein applied literature-based analysis confirms the hypothesis. Consequently, an alternative conceptual culture model is being introduced and discussed as theoretical foundation for culture research in DSR.
A framework of decision‐support systems in advanced manufacturing enterprises ‐ a systems view
(1997)
In the design of robot skills, the focus generally lies on increasing the flexibility and reliability of the robot execution process; however, typical skill representations are not designed for analysing execution failures if they occur or for explicitly learning from failures. In this paper, we describe a learning-based hybrid representation for skill parameterisation called an execution model, which considers execution failures to be a natural part of the execution process. We then (i) demonstrate how execution contexts can be included in execution models, (ii) introduce a technique for generalising models between object categories by combining generalisation attempts performed by a robot with knowledge about object similarities represented in an ontology, and (iii) describe a procedure that uses an execution model for identifying a likely hypothesis of a parameterisation failure. The feasibility of the proposed methods is evaluated in multiple experiments performed with a physical robot in the context of handle grasping, object grasping, and object pulling. The experimental results suggest that execution models contribute towards avoiding execution failures, but also represent a first step towards more introspective robots that are able to analyse some of their execution failures in an explicit manner.
Striated muscle contraction is regulated by the translocation of troponin-tropomyosin strands over the thin filament surface. Relaxation relies partly on highly-favorable, conformation-dependent electrostatic contacts between actin and tropomyosin, which position tropomyosin such that it impedes actomyosin associations. Impaired relaxation and hypercontractile properties are hallmarks of various muscle disorders. The α-cardiac actin M305L hypertrophic cardiomyopathy-causing mutation lies near residues that help confine tropomyosin to an inhibitory position along thin filaments. Here, we investigate M305L actin in vivo, in vitro, and in silico to resolve emergent pathological properties and disease mechanisms. Our data suggest the mutation reduces actin flexibility and distorts the actin-tropomyosin electrostatic energy landscape that, in muscle, result in aberrant contractile inhibition and excessive force. Thus, actin flexibility may be required to establish and maintain interfacial contacts with tropomyosin as well as facilitate its movement over distinct actin surface features and is, therefore, likely necessary for proper regulation of contraction.
Today’s computer systems face a vast array of severe threats that are posed by automated attacks performed by malicious software as well as manual attacks by individual humans. These attacks not only differ in their technical implementation but may also be location-dependent. Consequentially, it is necessary to join the information from heterogeneous and distributed attack sensors in order to acquire comprehensive information on current ongoing cyber attacks.
Currently, there are a lot of research activities dealing with gamma titanium aluminide (γ-TiAl) alloys as new materials for low pressure turbine (LPT) blades. Even though the scatter in mechanical properties of such intermetallic alloys is more distinctive as in conventional metallic alloys, stochastic investigations on γ -TiAl alloys are very rare. For this reason, we analyzed the scatter in static and dynamic mechanical properties of the cast alloy Ti-48Al-2Cr-2Nb. It was found that this alloy shows a size effect in strength which is less pronounced than the size effect of brittle materials. A weakest-link approach is enhanced for describing a scalable size effect under multiaxial stress states and implemented in a post processing tool for reliability analysis of real components. The presented approach is a first applicable reliability model for semi-brittle materials. The developed reliability tool was integrated into a multidisciplinary optimization of the geometry of a LPT blade. Some processes of the optimization were distributed in a wide area network, so that specialized tools for each discipline could be employed. The optimization results show that it is possible to increase the aerodynamic efficiency and the structural mechanics reliability at the same time, while ensuring the blade can be manufactured in an investment casting process.
Earth’s nearest candidate supermassive black hole lies at the centre of the Milky Way1. Its electromagnetic emission is thought to be powered by radiatively inefficient accretion of gas from its environment2, which is a standard mode of energy supply for most galactic nuclei. X-ray measurements have already resolved a tenuous hot gas component from which the black hole can be fed3. The magnetization of the gas, however, which is a crucial parameter determining the structure of the accretion flow, remains unknown. Strong magnetic fields can influence the dynamics of accretion, remove angular momentum from the infalling gas4, expel matter through relativistic jets5 and lead to synchrotron emission such as that previously observed6, 7, 8. Here we report multi-frequency radio measurements of a newly discovered pulsar close to the Galactic Centre9, 10, 11, 12 and show that the pulsar’s unusually large Faraday rotation (the rotation of the plane of polarization of the emission in the presence of an external magnetic field) indicates that there is a dynamically important magnetic field near the black hole. If this field is accreted down to the event horizon it provides enough magnetic flux to explain the observed emission—from radio to X-ray wavelengths—from the black hole.
A structural mapping of mutations causing succinyl-CoA:3-ketoacid CoA transferase (SCOT) deficiency
(2013)
Succinyl-CoA:3-ketoacid CoA transferase (SCOT) deficiency is a rare inherited metabolic disorder of ketone metabolism, characterized by ketoacidotic episodes and often permanent ketosis. To date there are ~20 disease-associated alleles on the OXCT1 gene that encodes the mitochondrial enzyme SCOT. SCOT catalyzes the first, rate-limiting step of ketone body utilization in peripheral tissues, by transferring a CoA moiety from succinyl-CoA to form acetoacetyl-CoA, for entry into the tricarboxylic acid cycle for energy production. We have determined the crystal structure of human SCOT, providing a molecular understanding of the reported mutations based on their potential structural effects. An interactive version of this manuscript (which may contain additional mutations appended after acceptance of this manuscript) may be found on the web address:
http://www.thesgc.org/jimd/SCOT
Updating a shared data structure in a parallel program is usually done with some sort of high-level synchronization operation to ensure correctness and consistency. The realization of such high-level synchronization operations is done with appropriate low-level atomic synchronization instructions that the target processor architecture provides. These instructions are costly and often limited in their scalability on larger multi-core / multi-processor systems. In this paper, a technique is discussed that replaces atomic updates of a shared data structure with ordinary and cheaper read/write operations. The necessary conditions are specified that must be fulfilled to ensure overall correctness of the program despite missing synchronization. The advantage of this technique is the reduction of access costs as well as more scalability due to elided atomic operations. But on the other side, possibly more work has to be done caused by missing synchronization. Therefore, additional work is traded against costly atomic operations. A practical application is shown with level-synchronous parallel Breadth-First Search on an undirected graph where two vertex frontiers are accessed in parallel. This application scenario is also used for an evaluation of the technique. Tests were done on four different large parallel systems with up to 64-way parallelism. It will be shown that for the graph application examined the amount of additional work caused by missing synchronization is neglectible and the performance is almost always better than the approach with atomic operations.
The article explores SME (Small and Medium Sized Enterprises) brand strategies as a means to position and successfully engage in competitive markets. A derived typology of brand strategy types deals with social profiling and sheds light on brand strategy internalization of two current managerial paradigms—sustainability and co-creation. N = 895 German SME wineries were examined, leaning on a netnographic analysis of predominantly websites and social media interactions. A two-step clustering method thereby identified eight winery SME brand strategy types. The importance of sustainability across the identified eight brand strategy types is significant. Co-creation turned out to be a key profiling trait characterizing one brand strategy type. The typology illustrates strategic richness, with brand strategies leaning predominantly on traditional values, on sustainability, on external reputation, or on more innovative customer centric concepts such as co-creation. Hereby, the typology and the identified brand levers invite to strategically design brand management, governance, and sustainability. Wineries which focus on traditional positioning and legitimacy were found to be cautious in deploying co-creation through social media. Winery brands that are characterized by engagement in digital co-creation apparently either tend to expand their scope or partially combine it with traditional values, making them the most diverse type identified. Sustainability obviously needs to be addressed by all brand strategies. Despite industry and country focus, the analyses illustrate the relevance of socially-oriented profiling and highlights that sustainability has reached a status of a fundamental business approach still allowing to differentiate thereon. Furthermore, the business models of the SMEs need to deliver communicated values.
We present a system that combines voxel and polygonal representations into a single octree acceleration structure that can be used for ray tracing. Voxels are well-suited to create good level-of-detail for high-frequency models where polygonal simplifications usually fail due to the complex structure of the model. However, polygonal descriptions provide the higher visual fidelity. In addition, voxel representations often oversample the geometric domain especially for large triangles, whereas a few polygons can be tested for intersection more quickly.
AAV-encoded expression of TRAIL in experimental human colorectal cancer leads to tumor regression
(2004)
Abschlussarbeiten FAQ/FGA
(2006)
Herein we report an update to ACPYPE, a Python3 tool that now properly converts AMBER to GROMACS topologies for force fields that utilize nondefault and nonuniform 1–4 electrostatic and nonbonded scaling factors or negative dihedral force constants. Prior to this work, ACPYPE only converted AMBER topologies that used uniform, default 1–4 scaling factors and positive dihedral force constants. We demonstrate that the updated ACPYPE accurately transfers the GLYCAM06 force field from AMBER to GROMACS topology files, which employs non-uniform 1–4 scaling factors as well as negative dihedral force constants. Validation was performed using β-d-GlcNAc through gas-phase analysis of dihedral energy curves and probability density functions. The updated ACPYPE retains all of its original functionality, but now allows the simulation of complex glycomolecular systems in GROMACS using AMBER-originated force fields. ACPYPE is available for download at https://github.com/alanwilter/acpype.
At present, data publication is one of the most dynamic topics in e-Research. While the fundamental problems of electronic text publication have been solved in the past decade, standards for the external and internal organisation of data repositories are advanced in some research disciplines but underdeveloped in others. We discuss the differences between an electronic text publication and a data publication and the challenges that result from these differences for the data publication process. We place the data publication process in the context of the human knowledge spiral and discuss key factors for the successful acquisition of research data from the point of view of a data repository. For the relevant activities of the publication process, we list some of the measures and best practices of successful data repositories.
Hydrogen sulfide (H2S) is well known as a highly toxic environmental chemical threat. Prolonged exposure to H2S can lead to the formation of pulmonary edema. However, the mechanisms of how H2S facilitates edema formation are poorly understood. Since edema formation can be enhanced by an impaired clearance of electrolytes and, consequently, fluid across the alveolar epithelium, it was questioned whether H2S may interfere with transepithelial electrolyte absorption. Electrolyte absorption was electrophysiologically measured across native distal lung preparations (Xenopus laevis) in Ussing chambers. The exposure of lung epithelia to H2S decreased net transepithelial electrolyte absorption. This was due to an impairment of amiloride-sensitive sodium transport. H2S inhibited the activity of the Na+/K+-ATPase as well as lidocaine-sensitive potassium channels located in the basolateral membrane of the epithelium. Inhibition of these transport molecules diminishes the electrochemical gradient which is necessary for transepithelial sodium absorption. Since sodium absorption osmotically facilitates alveolar fluid clearance, interference of H2S with the epithelial transport machinery provides a mechanism which enhances edema formation in H2S-exposed lungs.
The introduction of new steering conceptsSteer-by-Wire (SBW) gives possibility to replace theconventional steering wheel by an alternative userinterface such as a sidestick. In SBW system the sidestickcan be used as user input element instead of a steeringwheel. The implementation of sidestick in the Human-Machine-Interface (HMI) allows combiningthe conventional steering consisting of a steeringwheel, an accelerator and a brake pedal into a singleelement. Also the implementation of the sidestickcreates new, interesting and flexible design optionswhich can be used to transform the driver’s spatialenvironment. This article describes an active sidestickfor a vehicle which has been developed, integrated andtested in accordance of haptic, ergonomic and safetyrelevant requirements. The control strategies used forthe active attenuators of the sidestick have beeninvestigated and optimised using a Simulink model.
Adaptability as a Special Demand on Open Educational Resources: The Cultural Context of e-Learning
(2011)
Producing and providing Open Educational Resources (OERs) is driven by the concepts of openness and sharing. Although there already are a lot of free high-quality resources available, practitioners often rather rewrite learning resources than creatively embed (and thus, reuse) existing OERs. In this paper, we analyse the reasons for this in two different educational contexts. As a result of this analysis, we found that the uncertainty on possible adaptation needs is one of the major barriers. In order to overcome this barrier and make different learning contexts comparable, we analysed the context of learners and in particular, in the research project ‘Learning Culture’, we investigated the field of culturally motivated expectations and attitudes of learners. This paper shows the results of this research project and discusses which cultural issues should be taken into consideration when OERs are to be adapted from one to another cultural context.
Adaptation of e-Learning Environments: Determining National Differences through Context Metadata
(2008)
The paper shows how existing e-learning modules can be internationalized using structured information on the context and specifically culture. Reusing e-Learning contents is a promising concept for the internationalization or cross-cultural purposes. However, most adaptation efforts are often limited to pure language translation.
As the only alternative is rewriting, reusability allows a massive cost reduction by implementing and adapting already established courses, for example into developing countries on a low-cost level. Our approach provides a basis for international and cross-cultural adaptation. In the approach, we identify, collect and store as many parameters about the source and target context and culture as available. After comparing contexts, we determine changing needs by analyzing the impacting differences.
To implement this approach on a large-scale, we plan a public database containing the necessary information for the comparison process. In our research, we have identified a set of around 170 parameters describing national and, more specifically, cultural attributes related to various situations. Utilizing those in an adequate way will lead to an easier and efficient adaptation process.
Adoption of Modern Maize Varieties in India: Insights Based on Expert Elicitation Methodology
(2018)
Advanced thermal gradient mechanical fatigue testing of CMSX-4 with an oxidation protection coating
(2008)
This paper presents recent research on an active multispectral scanning sensor capable of classifying an object's surface material in order to distinguish between different kinds of materials and human skin. The sensor itself has already been presented in previous work and can be used in conjunction with safeguarding equipment at manually-fed machines or robot workplaces, for example. This work shows how an extended sensor system with advanced material classifiers can be used to provide additional value by distinguishing different materials of work pieces in order to suggest different tools or parameters for the machine (e.g. the use of a different saw blade or rotation speed at table saws). Additionally, a first implementation and evaluation of an active multispectral camera system addressing new safety applications is described. Both approaches intend to increase the productivity and the user's acceptance of the sensor technology.
One of the main aims of current social robotic research is to improve the robots’ abilities to interact with humans. In order to achieve an interaction similar to that among humans, robots should be able to communicate in an intuitive and natural way and appropriately interpret human affects during social interactions. Similarly to how humans are able to recognize emotions in other humans, machines are capable of extracting information from the various ways humans convey emotions-including facial expression, speech, gesture or text-and using this information for improved human computer interaction. This can be described as Affective Computing, an interdisciplinary field that expands into otherwise unrelated fields like psychology and cognitive science and involves the research and development of systems that can recognize and interpret human affects. To leverage these emotional capabilities by embedding them in humanoid robots is the foundation of the concept Affective Robots, which has the objective of making robots capable of sensing the user’s current mood and personality traits and adapt their behavior in the most appropriate manner based on that. In this paper, the emotion recognition capabilities of the humanoid robot Pepper are experimentally explored, based on the facial expressions for the so-called basic emotions, as well as how it performs in contrast to other state-of-the-art approaches with both expression databases compiled in academic environments and real subjects showing posed expressions as well as spontaneous emotional reactions. The experiments’ results show that the detection accuracy amongst the evaluated approaches differs substantially. The introduced experiments offer a general structure and approach for conducting such experimental evaluations. The paper further suggests that the most meaningful results are obtained by conducting experiments with real subjects expressing the emotions as spontaneous reactions.
Seit vielen Jahren ist der Übergang von der Schule zur Hochschule eines der zentralen Themen für didaktische Theorien, empirische Untersuchungen und bildungspolitische Diskussionen. Ein dabei identifiziertes großes Problem vieler Studierender ist, dass mit dem Abitur „eine Lebensphase mit meist klar definierten Zielen in überschaubaren räumlichen, familiären und schulischen Strukturen endet“.1) Entscheidet man sich als Studierender gegen die nicht akademische Laufbahn und nimmt ein Hochschulstudium auf, trifft man auf Studienstrukturen und -bedingungen, die einem fremd und chaotisch vorkommen können. Der Weg an die Hochschulen ermöglicht den Individuen eine Reihe von Optionen, ist aber leider auch immer mit Risiken und Unsicherheiten behaftet. Entscheidungen müssen nun selbstständig vorbereitet und getroffen werden und dies in einem Umfeld, das sehr unterschiedlich im Vergleich zur bekannten Schulstruktur sein kann.
Alleine Bowling spielen?
(2021)
Womöglich ist das social distancing dieser Tage gar kein soziales sondern einfach nur ein körperliches, ein body distancing. Sozial können wir heute auch sein, ohne uns physisch zu begegnen. Wir können sogar "gemeinsam einsam" musizieren oder im Chor singen. Trotzdem geht etwas verloren - und am Ende wissen wir Zusammenkünfte in Vereinen welcher Art auch immer vielleicht wieder besonders zu schätzen.
Allgemeines Steuerrecht
(2015)