195 research outputs found
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A Rational Scheme for Conflict Detection and Resolution in Distributed Collaborative Environments for Enterprise Integration
A typical enterprise may have large numbers of information sources such as data stores, expert systems, knowledge-based systems, or standard software systems. These may need to be integrated so that, for example, an application program or a decision maker can access information from all these sources. Such architectures are generally called 'Distributed Collaborative Environments for Enterprise Integration'.
A general problem in these enterprise integration architectures is that information from heterogeneous, pre-existing sources may be obsolete, incomplete, incorrect or, for many other reasons, contradictory. Thus, conflicting results may occur when the same information is requested from semantically related sources. A mechanism is required to detect and resolve these conflicts in a way that is rational to any potential client of the integration environment.
This thesis lays open the design of a general mechanism for conflict detection and resolution that enables intelligent information agents to reason about contradictory information from pre-existing, heterogeneous and autonomous sources. The mechanism's theoretical basis is a framework that is drawn from evidence law, which shares some fundamental commonalities with conflict detection and resolution in enterprise integration environments.
Conflict detection opens with gathering the results collected by the information retrieval process. These results may have justifications or certainty assessments attached to them. Furthermore, it identifies whether and how these results are conflicting.
The design of a conflict resolution mechanism is based on a rational scheme for judging the weight of conflicting results. First, the agents assess the reliability or credibility of an information source. Judgement based on the weight of conflicting results is first applied to any available, domain-specific, resolution strategies. Second, the agent applies any 'general scientific' resolution strategies that are not specific to one domain. When no domain-related expertise can solve the conflict then the agent can only judge on domain independent evaluation criteria such as the results' reliability. A scheme is sketched out for judgement based on the reliability of conflicting results, involving three steps: Ranking the conflicting results according to their reliability; Ways to redefine conflicting results; and Heuristic decision-making.
The evaluation includes a computational implementation of an enterprise integration environment incorporating a model of an information agent. An example is realised in this environment. The conflict detection and resolution mechanism, and interfaces to each integrated source, are implemented in Visual C++. A case study is conducted on this scenario to evaluate each conflict detection and resolution step. Furthermore, this illustrates both the advantages over existing approaches and the limitations
Mechanical activation of vinculin binding to talin locks talin in an unfolded conformation
The force-dependent interaction between talin and vinculin plays a crucial role in the initiation and growth of focal adhesions. Here we use magnetic tweezers to characterise the mechano-sensitive compact N-terminal region of the talin rod, and show that the three helical bundles R1-R3 in this region unfold in three distinct steps consistent with the domains unfolding independently. Mechanical stretching of talin R1-R3 enhances its binding to vinculin and vinculin binding inhibits talin refolding after force is released. Mutations that stabilize R3 identify it as the initial mechano-sensing domain in talin, unfolding at ~5 pN, suggesting that 5 pN is the force threshold for vinculin binding and adhesion progression
Neurobiological Correlates of Decision-Making in Framing Conditions
Human decision-making is a complex process, of which the neurobiological correlates are not well understood. Several theories have been proposed, among others Prospect theory which assumes a different evaluation of gains and losses of the same value. De Martino et al. tested the influence of the “framing effect” on decision-making and we aimed to replicate their study as some of the findings remained unclear. A general tendency to act in accordance with the frame was shown in a behavioural study. In order to uncover the underlying neural correlates, participants performed the same task in an fMRI scanner. Even though the amygdala could not be linked to framing, increased activity in the ACC when making frame-incongruent decisions was established. This can be related to acting in a more rational manner. Furthermore, activity in the cerebellum was increased when making a choice, indicating the involvement of this brain area in decision-making under uncertainty
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The Resonance of Resonance: Critical Theory as a Sociology of World-Relations?
The main purpose of this paper is to examine Hartmut Rosa’s account of “resonance.” To this end, the analysis is divided into four parts. The first part focuses on the concept of resonance, including Rosa’s differentiation between horizontal, diagonal, and vertical “axes of resonance” and their role in the construction of different “world-relations.” The second part centers on the concept of alienation, notably the degree to which it constitutes an integral element of modern life forms and, in a larger sense, of the human condition. The third part grapples with the dialectic of resonance and alienation, shedding light on the assumption that they are antithetical to each other, while contending that their in-depth study provides normative parameters to distinguish between “the good life” and “the bad life.” The final part scrutinizes Rosa’s attempt to defend his outline of a sociological theory of resonance against objections raised by his critics and comprises a point-by-point assessment of his plea for a resonance-focused sociology of world-relations. The paper concludes by suggesting that, notwithstanding its limitations, Rosa’s approach represents one of the most promising developments in twenty-first-century critical theory
Control and Manipulation of Pathogens with an Optical Trap for Live Cell Imaging of Intercellular Interactions
The application of live cell imaging allows direct visualization of the dynamic interactions between cells of the immune system. Some preliminary observations challenge long-held beliefs about immune responses to microorganisms; however, the lack of spatial and temporal control between the phagocytic cell and microbe has rendered focused observations into
the initial interactions of host response to pathogens difficult. This paper outlines a method that advances live cell imaging by integrating a spinning disk confocal microscope with an optical trap, also known as an optical tweezer, in order to provide exquisite spatial and temporal control of pathogenic organisms and place them in proximity to host cells, as
determined by the operator. Polymeric beads and live, pathogenic organisms (Candida albicans and Aspergillus fumigatus) were optically trapped using non-destructive forces and moved adjacent to living cells, which subsequently phagocytosed the trapped particle. High resolution, transmitted light and fluorescence-based movies established the ability to observe early events of phagocytosis in living cells. To demonstrate the broad applicability of this method to immunological studies, anti-CD3 polymeric beads were also trapped and manipulated to form synapses with T cells in vivo, and time-lapse imaging of synapse formation was also obtained. By providing a method to exert fine control of live pathogens with respect to immune cells, cellular interactions can be captured by fluorescence microscopy with minimal perturbation to cells and can
yield powerful insight into early responses of innate and adaptive immunity.National Institute of Biomedical Imaging and Bioengineering (U.S.) (grant T32EB006348)Massachusetts General Hospital (Department of Medicine Internal Funds)Center for Computational and Integrative Biology (Development fund)Center for Computational and Integrative Biology (AI062773)Center for Computational and Integrative Biology (grant AI062773)Center for Computational and Integrative Biology (grant DK83756)Center for Computational and Integrative Biology (grant DK 043351)National Institute of Allergy and Infectious Diseases (U.S.)National Institutes of Health (U.S.) (grant AI057999
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