1,721,582 research outputs found
Christian Bason: Design for public service
No full textChristian Bason is the Chief Executive of the Danish Design Center, which works to advance the use of design in business and society. From 2007 to 2014, he was Director of MindLab, the Danish cross-governmental innovation team. Prior to this he was a consultant and business manager with the international advisory group Ramboll. Christian is the author of multiple books on innovation and design in government, including Leading Public Design: Discovering Human-Centred Governance (2017), Design for Policy (2014) and Leading Public Sector Innovation: Co-creating for a Better Society (2010)
-diagram technique for , superfields
No full textWe describe a diagrammatic procedure to carry out the Grassmann integration in super-Feynman diagrams of 4d theories expressed in terms of superfields. This method is alternative to the well known D-algebra approach. We develop it in detail for theories containing vector, chiral and anti-chiral superfields, with the type of interactions which occur in SYM theories with massless matter, but it would be possible to extend it to other cases. The main advantage is that this method is algorithmic; we implemented it as a Mathematica program that, given the description of a super Feynman diagram in momentum space, returns directly the polynomial in the momenta produced by the Grassmann integration
Condizioni al bordo di teorie di gauge N=2 tetradimensionali
No full textIn questa tesi esploriamo la dinamica delle teorie di gauge supersimmetriche 4d N=2 in presenza di bordo, con 1/2-BPS condizioni al bordo, in diversi scenari. Lo facciamo con l'obiettivo di migliorare strumenti analitici per modelli progressivamente meno vincolati e per migliorare la nostra comprensione della dinamica introdotta dai bordi in teorie quantistiche di campo oltre il regime perturbativo. Intendiamo anche far progredire la conoscenza dello spazio consentito delle condizioni al contorno in funzione dei parametri di una teoria e della scala energetica. Un' importante classe di modelli che abbiamo preso in considerazione sono le teorie di campo conformi con bordo, che possono essere realizzate in natura in transizioni di fase di secondo ordine per sistemi racchiusi in regioni finite. In questo contesto abbiamo studiato come calcolare esattamente la funzione a un punto degli operatori chirali 4d N=2 mediante localizzazione supersimmetrica, collegando questi calcoli alle derivate della funzione di partizione dell'emisfero e del suo coniugato. Abbiamo anche avviato uno studio teorico delle stringhe, tramite costruzioni di brane, che realizzano queste teorie di campo. Ciò ci consente di discutere le dualità tra regimi debolmente e fortemente accoppiati. Come ulteriore applicazione della nostra comprensione delle teorie di gauge supersimmetriche con confini, avviamo uno studio di teorie N=2 asintoticamente libere in AdS4. In questa configurazione, la scala di curvatura svolge il ruolo di un regolatore IR che consente di interpolare tra il regime UV debolmente accoppiato e quello IR fortemente accoppiato. Grazie alla supersimmetria siamo in grado di ottenere nuovi risultati esatti che utilizziamo per studiare le condizioni al contorno disponibili e il loro comportamento quando modifichiamo il raggio di AdS. In particolare ci concentriamo sullo studio di quando le condizioni al contorno di Dirichlet, possibili solo quando esistono stati asintotici colorati, si destabilizzano, segnalando così la fine della fase deconfinata.In this thesis we explore the dynamics of 4d N=2 supersymmetric gauge theories in presence of a boundary, with 1/2-BPS boundary conditions, in different scenarios. We do this with the aim of enlarging the scopes of analytical tools, for progressively less constrained models, and for improving our comprehension of the dynamics of boundaries in quantum field theory beyond the perturbative regime. We also intend to advance the knowledge of the allowed space of boundary conditions in function of the parameters of a theory and the energy scale. An important class of models we considered are boundary Conformal Field Theories, which can be realized in nature at second order phase transition for a system enclosed in a finite region. Within this context we studied how to exactly compute the one-point function of 4d N=2 chiral operators by means of supersymmetric localization, relating these computations to derivatives of the hemisphere partition function and its conjugate. We also initiate a string theoretic study of brane constructions realizing these field theoretic systems. This allows us to argue dualities among weakly and strongly coupled regimes. As a further application of our understanding of supersymmetric gauge theories with boundaries, we initiate a study of asymptotically free N=2 theories in AdS4. In this set up, the curvature scale plays the role of an IR regulator which allows to interpolate between the weakly coupled UV regime and the strongly coupled IR one. Thanks to supersymmetry we are able to obtain novel exact results that we use to study the available boundary conditions and their behaviour as we change the AdS radius. In particular we focus on studying when Dirichlet boundary conditions, possible only when colored asymptotic states exists, destabilize, thus signalling the end of the deconfined phase
Induction of endothelial cell damage by hCMV molecular mimicry
No full textMolecular mimicry between infectious agents and normal human host cell components is one of the mechanisms responsible for autoimmunity. Among infectious agents, some viruses represent ideal candidates for their ability to infect human cells, where they are harbored for the duration of the life of the host in a latent state. Human cytomegalovirus (hCMV) infection has been implicated in the pathogenesis of vascular damage in systemic sclerosis (SSc) and atherosclerosis. Based on recent data describing a cause and effect relationship between hCMV and endothelial cell damage in SSc and atherosclerosis, we propose that the immune response to particular hCMV proteins might result in autoaggression through a mechanism of molecular mimicry of normally expressed endothelial cell surface molecules
ANTROPOLOGENS ROLLE I INNOVATION: Interview med Christian Bason
No full textI interviewet med Christoffer Nejrup fra temaredaktionen giver Christian Bason, administrerende direktør for Dansk Design Center, sit bud på, hvorfor han ser antropologer som afgørende for innovation, hvilken rolle antropologen har, og hvilke kompetencer en antropolog bør have for at gøre sig gældende i denne branche
The Extracellular Matrix, Growth Factors and Morphogens in Biomaterial Design and Tissue Engineering
No full textCells, morphogens, growth factors, and custom scaffolds are the critical ingredients for successful tissue regeneration in which morphogens and growth factors function sequentially. Extensive studies, in vitro and in vivo, have been made to explore the mechanisms and the roles played by these molecules. As a consequence, precise, localized control over the signaling of these factors and appropriate strategy selection, depending on the tissue or organ to be repaired or regenerated, is known to permit specific management of regenerative processes. The first part of the chapter examines natural ECMs which are a set of molecules secreted by cells that provide structural and biochemical support to the surrounding cells. ECMs also perform many other functions, such as actively regulating cell function through the control of biochemical gradients, cell density, spatial organization, and ligand attachment, thus influencing various types of cell processes. Subsequently, growth factors and morphogens are examined in greater depth to clarify to what degree progress has been made into improving methodologies and functionality and, perhaps, to hint at what remains to be done for the future of tissue engineering
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Immunopathogenesis of Systemic Sclerosis
No full textSystemic Sclerosis is a multysistem disorder of connective tissue characterized by an autoimmune background and fibrosis of the skin and internal organs following endothelial cell damage. The etiopathogenesis is complex and still poorly understood; however the results of the most recent research have provided significant advances in understanding of the events that lead to the onset and/or progression of the disease. Interactions among endothelial cells, lymphoid cells and fibroblast are likely to be central to the pathogenesis of the disease. Increasing evidence suggests that environmental factors, such as infectious agents, may trigger the onset of the disease in genetically susceptible individuals.
In this chapter we briefly describe some aspects of SSc pathogenesis and concentrate on the endothelial cell damage following human cytomegalovirus infection
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