2,552 research outputs found
FuturICT: Participatory computing to understand and manage our complex world in a more sustainable and resilient way
We have built particle accelerators to understand the forces that make up our physical world. Yet, we do not understand the princi-ples underlying our strongly connected, techno-socio-economic systems. We have enabled ubiquitous Internet connectivity and instant, global information access. Yet we do not understand how it impacts our be-havior and the evolution of society. To fill the knowledge gaps and keep up with the fast pace at which our world is changing, a Knowledge Accelerator must urgently be cre-ated. The financial crisis, international wars, global terror, the spread-ing of diseases and cyber-crime as well as demographic, technological and environmental change demonstrate that humanity is facing seri-ous challenges. These problems cannot be solved within the traditional paradigms. Moving our attention from a component-oriented view of the world to an interaction-oriented view will allow us to understand the com-plex systems we have created and the emergent collective phenomena characterising them. This paradigm shift will enable new solutions to long-standing problems, very much as the shift from a geocentric to a heliocentric worldview has facilitated modern physics and the ability to launch satellites. The FuturICT flagship project will develop new science and technology to manage our future in a complex, strongly connected world. For this, it will combine the power of information and communication technol-ogy (ICT) with knowledge from the social and complexity sciences. ICT will provide the data to boost the social sciences into a new era. Complexity science will shed new light on the emergent phenomena in socially interactive systems, and the social sciences will provide a better understanding of the opportunities and risks of strongly net-worked systems, in particular future ICT systems. Hence, the envisaged FuturICT flagship will create new methods and instruments to tackle the challenges of the 21 st century. FuturICT could indeed become one of the most important scientific endeavours ever, by revealing the principles that make socially inter-active systems work well, by inspiring the creation of new platforms to explore our possible futures, and by initiating an era of social and socio-inspired innovations
Chondrogenic Potency Analyses of Donor-Matched Chondrocytes and Mesenchymal Stem Cells Derived from Bone Marrow, Infrapatellar Fat Pad, and Subcutaneous Fat.
Autologous chondrocyte implantation (ACI) is a cell-based therapy that has been used clinically for over 20 years to treat cartilage injuries more efficiently in order to negate or delay the need for joint replacement surgery. In this time, very little has changed in the ACI procedure, but now many centres are considering or using alternative cell sources for cartilage repair, in particular mesenchymal stem cells (MSCs). In this study, we have tested the chondrogenic potential of donor-matched MSCs derived from bone marrow (BM), infrapatellar fat pad (FP), and subcutaneous fat (SCF), compared to chondrocytes. We have confirmed that there is a chondrogenic potency hierarchy ranging across these cell types, with the most potent being chondrocytes, followed by FP-MSCs, BM-MSCs, and lastly SCF-MSCs. We have also examined gene expression and surface marker profiles in a predictive model to identify cells with enhanced chondrogenic potential. In doing so, we have shown that Sox-9, Alk-1, and Coll X expressions, as well as immunopositivity for CD49c and CD39, have predictive value for all of the cell types tested in indicating chondrogenic potency. The findings from this study have significant clinical implications for the refinement and development of novel cell-based cartilage repair strategies
Virtual and Augmented Reality in Finance: State Visibility of Events and Risk
International audienceThe recent financial crisis and its aftermath motivate our re-thinking of the role of Information and Communication Technologies (ICT) as a driver for change in global finance and a critical factor for success and sustainability. We attribute the recent financial crisis that hit the global market, causing a drastic economic slowdown and recession, to a lack of state visibility of risk, inadequate response to events, and a slow dynamic system adaptation to events. There is evidence that ICT is not yet appropriately developed to create business value and business intelligence capable of counteracting devastating events. The aim of this chapter is to assess the potential of Virtual Reality and Augmented Reality (VR / AR) technologies in supporting the dynamics of global financial systems and in addressing the grand challenges posed by unexpected events and crises. We overview, firstly, in this chapter traditional AR/VR uses. Secondly, we describe early attempts to use 3D/ VR / AR technologies in Finance. Thirdly, we consider the case study of mediating the visibility of the financial state and we explore the various dimensions of the problem. Fourthly, we assess the potential of AR / VR technologies in raising the perception of the financial state (including financial risk). We conclude the chapter with a summary and a research agenda to develop technologies capable of increasing the perception of the financial state and risk and counteracting devastating events
Magnetic Resonance Imaging Parameters at 1 Year Correlate With Clinical Outcomes Up to 17 Years After Autologous Chondrocyte Implantation
Background: The ability to predict the long-term success of surgical treatment in orthopaedics is invaluable, particularly in clinical trials. The quality of repair tissue formed 1 year after autologous chondrocyte implantation (ACI) in the knee was analyzed and compared with clinical outcomes over time. Hypothesis: Better quality repair tissue and a better appearance on magnetic resonance imaging (MRI) 1 year after ACI lead to improved longer-term clinical outcomes. Study Design: Cohort study; Level of evidence, 3. Methods: Repair tissue quality was assessed using either MRI (11.5 ± 1.4 [n = 91] or 39.2 ± 18.5 [n = 76] months after ACI) or histology (16.3 ± 11.0 months [n = 102] after ACI). MRI scans were scored using the whole-organ magnetic resonance imaging score (WORMS) and the magnetic resonance observation of cartilage repair tissue (MOCART) score, with additional assessments of subchondral bone marrow and cysts. Histology of repair tissue was performed using the Oswestry cartilage score (OsScore) and the International Cartilage Repair Society (ICRS) II score. Clinical outcomes were assessed using the modified Lysholm score preoperatively, at the time of MRI or biopsy, and at a mean 8.4 ± 3.7 years (maximum, 17.8 years) after ACI. Results: At 12 months, the total MOCART score and some of its individual parameters correlated significantly with clinical outcomes. The degree of defect fill, overall signal intensity, and surface of repair tissue at 12 months also significantly correlated with longer-term outcomes. The presence of cysts or effusion (WORMS) significantly correlated with clinical outcomes at 12 months, while the presence of synovial cysts/bursae preoperatively or the absence of loose bodies at 12 months correlated significantly with long-term clinical outcomes. Thirty percent of repair tissue biopsies contained hyaline cartilage, 65% contained fibrocartilage, and 5% contained fibrous tissue. Despite no correlation between the histological scores and clinical outcomes at the time of biopsy, a lack of hyaline cartilage or poor basal integration was associated with increased pain; adhesions visible on MRI also correlated with significantly better histological scores. Conclusion: These results demonstrate that MRI at 12 months can predict longer-term clinical outcomes after ACI. Further investigation regarding the presence of cysts, effusion, and adhesions and their relationship with histological and clinical outcomes may yield new insights into the mechanisms of cartilage repair and potential sources of pain
Human Articular Chondrocytes Retain Their Phenotype in Sustained Hypoxia While Normoxia Promotes Their Immunomodulatory Potential.
Objective To assess the phenotype of human articular chondrocytes cultured in normoxia (21% O2) or continuous hypoxia (2% O2). Design Chondrocytes were extracted from patients undergoing total knee replacement ( n = 5) and cultured in ~21% (normoxic chondrocytes, NC) and 2% (hypoxic chondrocytes, HC) oxygen in both monolayer and 3-dimensional (3D) pellet culture and compared with freshly isolated chondrocytes (FC). Cells were assessed by flow cytometry for markers indicative of mesenchymal stromal cells (MSCs), chondrogenic-potency and dedifferentiation. Chondrogenic potency and immunomodulatory gene expression was assessed in NC and HC by reverse transcription quantitative polymerase chain reaction. Immunohistochemistry was used to assess collagen II production following 3D pellet culture. Results NC were positive (>97%, n = 5) for MSC markers, CD73, CD90, and CD105, while HC demonstrated 60%) compared with HC and FC in which production was <2%. Hypoxic conditions upregulated expression of SOX9, frizzled-related protein ( FRZB), fibroblast growth factor receptor 3 ( FGFR3), and collagen type II ( COL2A1) and downregulated activin receptor-like kinase 1 ( ALK1) in 3 out of 4 patients compared with normoxic conditions for monolayer cells. Conclusions Hypoxic conditions encourage retention of a chondrogenic phenotype with some immunomodulatory potential, whereas normoxia promotes dedifferentiation of chondrocytes toward an MSC phenotype with loss of chondrogenic potency but enhanced immunomodulatory capacity
A Holder Continuous Nowhere Improvable Function with Derivative Singular Distribution
We present a class of functions in which is variant
of the Knopp class of nowhere differentiable functions. We derive estimates
which establish \mathcal{K} \sub C^{0,\al}(\R) for 0<\al<1 but no is pointwise anywhere improvable to C^{0,\be} for any \be>\al.
In particular, all 's are nowhere differentiable with derivatives singular
distributions. furnishes explicit realizations of the functional
analytic result of Berezhnoi.
Recently, the author and simulteously others laid the foundations of
Vector-Valued Calculus of Variations in (Katzourakis), of
-Extremal Quasiconformal maps (Capogna and Raich, Katzourakis) and of
Optimal Lipschitz Extensions of maps (Sheffield and Smart). The "Euler-Lagrange
PDE" of Calculus of Variations in is the nonlinear nondivergence
form Aronsson PDE with as special case the -Laplacian.
Using , we construct singular solutions for these PDEs. In the
scalar case, we partially answered the open regularity problem of
Viscosity Solutions to Aronsson's PDE (Katzourakis). In the vector case, the
solutions can not be rigorously interpreted by existing PDE theories and
justify our new theory of Contact solutions for fully nonlinear systems
(Katzourakis). Validity of arguments of our new theory and failure of classical
approaches both rely on the properties of .Comment: 5 figures, accepted to SeMA Journal (2012), to appea
Towards a framework for the evaluation of mobile payments integration
This paper derives a theoretical framework for consideration of both the technologically
driven dimensions of mobile payment solutions, and the associated value proposition for customers.
Banks promote traditional payment instruments whose value proposition is the management of risk for
both consumers and merchants. These instruments are centralised, costly and lack decision support
functionality. The ubiquity of the mobile phone has provided a decentralised platform for managing
payment processes in a new way, but the value proposition for customers has yet to be elaborated
clearly. This inertia has stalled the design of sustainable revenue models for a mobile payments
ecosystem. Merchants and consumers in the meantime are being seduced by the convenience of online
and mobile payment solutions. Adopting the purchase and payment process as the unit of
analysis, the current mobile payment landscape is reviewed with respect to the creation and
consumption of customer value. From this analysis, a framework is derived juxtaposing customer
value, related to what is being paid for, with payment integration, related to how payments are being
made. The framework provides a theoretical and practical basis for considering the contribution of
mobile technologies to the payments industry
Towards a framework for the evaluation of mobile payments integration
This paper derives a theoretical framework for consideration of both the technologically
driven dimensions of mobile payment solutions, and the associated value proposition for customers.
Banks promote traditional payment instruments whose value proposition is the management of risk for
both consumers and merchants. These instruments are centralised, costly and lack decision support
functionality. The ubiquity of the mobile phone has provided a decentralised platform for managing
payment processes in a new way, but the value proposition for customers has yet to be elaborated
clearly. This inertia has stalled the design of sustainable revenue models for a mobile payments
ecosystem. Merchants and consumers in the meantime are being seduced by the convenience of online
and mobile payment solutions. Adopting the purchase and payment process as the unit of
analysis, the current mobile payment landscape is reviewed with respect to the creation and
consumption of customer value. From this analysis, a framework is derived juxtaposing customer
value, related to what is being paid for, with payment integration, related to how payments are being
made. The framework provides a theoretical and practical basis for considering the contribution of
mobile technologies to the payments industry
Synaesthesia: a distinct entity that is an emergent feature of adaptive neurocognitive differences
In this article, I argue that synaesthesia is not on a continuum with neurotypical cognition. Synaesthesia is special: its phenomenology is different; it has distinct causal mechanisms; and is likely to be associated with a distinct neurocognitive profile. However, not all synaesthetes are the same, and there are quantifiable differences between them. In particular, the number of types of synaesthesia that a person possesses is a hitherto underappreciated variable that predicts cognitive differences along a number of dimensions (mental imagery, sensory sensitivity, attention to detail). Together with enhanced memory, this may constitute a common core of abilities that may go some way to explaining why synaesthesia might have evolved. I argue that the direct benefits of synaesthesia are generally limited (i.e. the synaesthetic associations do not convey novel information about the world) but, nevertheless, synaesthesia may develop due to other adaptive functions (e.g. perceptual ability, memory) that necessitate changes to design features of the brain. The article concludes by suggesting that synaesthesia forces us to reconsider what we mean by a ‘normal’ mind/brain. There may be multiple ‘normal’ neurodevelopmental trajectories that can sculpt very different ways of experiencing the world, of which synaesthesia is but one.
This article is part of a discussion meeting issue ‘Bridging senses: novel insights from synaesthesia’
Histological and Radiological Assessment of Endogenously Generated Repair Tissue In Vivo Following a Chondral Harvest.
OBJECTIVE: To examine repair tissue formed approximately 15 months after a chondral harvest in the human knee. DESIGN: Sixteen individuals (12 males, 4 females, mean age 36 ± 9 years) underwent a chondral harvest in the trochlea as a pre-requisite for autologous chondrocyte implantation (ACI) treatment. The harvest site was assessed via MRI at 14.3 ± 3.2 months and arthroscopy at 15 ± 3.5 months (using the Oswestry Arthroscopy Score [O-AS] and the International Cartilage Repair Society Arthroscopy Score [ICRS-AS]). Core biopsies (1.8 mm diameter, n = 16) of repair tissue obtained at arthroscopy were assessed histologically (using the ICRS II and OsScore histology scores) and examined via immunohistochemistry for the presence of collagen types I and II. RESULTS: The mean O-AS and ICRS-AS of the repaired harvest sites were 7.2 ± 3.2 and 10.1 ± 3.5, respectively, with 80.3% ± 26% repair fill depth on MRI. The histological quality of the repair tissue formed was variable, with some hyaline cartilage present in 50% of the biopsies; where this occurred, it was associated with a significantly higher ICRS-AS than those with no hyaline cartilage present (median 11 vs. 7.5, P = 0.049). Collagen types I and II were detected in 12/14 and 10/13 biopsies, respectively. CONCLUSIONS: We demonstrate good-quality structural repair tissue formed following cartilage harvest in ACI, suggesting this site can be useful to study endogenous cartilage repair in humans. The trochlea is less commonly affected by osteoarthritis; therefore, location may be critical for spontaneous repair. Understanding the mechanisms and factors influencing this could improve future treatments for cartilage defects
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