18 resultados para Multitude

em Aston University Research Archive


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The relationship of knowledge and liberties in modern societies presents a multitude of fascinating issues that deserve to be explored more systematically. The production of knowledge is dynamic, and the conditions and practice of freedom is undergoing transformation. These changes ensure that the linkages between liberty and knowledge are always subject to changes. In the past, the connection between scientific knowledge, democracy, and emancipation seemed self-evident. More recently, the close linkage between democracy and knowledge has been viewed with skepticism. This volume explores the relationship between knowledge and democracy, Do they support each other, do they mutually depend on each other, or are they perhaps even in conflict with each other? Does knowledge increase the freedom to act? If additional knowledge contributes to individual and social well being, does it also enhance freedoms? Knowledge and Democracy focuses on the interpenetration of knowledge, freedom and democracy, and does so from various perspectives, theoretical as well as practical. Modern societies are transforming themselves into knowledge societies. This has a fundamental impact on political systems and the relationship of citizens to large social institutions. The contributors to this book systemically explore whether, and in what ways, these modern-day changes and developments are connected to expansion of the capacities of individual citizens to act. They focus on the interrelation of democracy and knowledge, and the role of democratic institutions, as well as on the knowledge and social conduct of actors within democratic institutions. In the process of investigation, they arrive at a newplatform for future research and theory, one that is sensitive to present-day societal conflicts, cleavages, and transformations generated by new knowledge.

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The recent global „credit crunch? has brought sharply into focus the need for better understanding of what it takes for organisations to survive. This research seeks to help organisations maintain their „viability? – the ability to maintain a separate existence and survive on their own. Whilst there are a multitude of factors that contribute to organisational viability, information can be viewed as the lifeblood of organisations. This research increases our understanding of how organisations can manage information effectively to help maintain their viability. The viable systems model (VSM) is an established modelling technique that enables the detailed analysis of organisational activity to examine how the structure and functions performed in an organisation contribute to its „viability?. The VSM has been widely applied, in small/large companies, industries and governments. However, whilst the VSM concentrates on the structure and functions necessary for an organisation to be viable, it pays much less attention to information deployment in organisations. Indeed, the VSM is criticised in the literature for being unable to provide much help with detailed information and communication structures and new theories are called for to explore the way people interact and what information they need in the VSM. This research analyses qualitative data collected from four case studies to contribute to our understanding of the role that information plays in organisational viability, making three key contributions to the academic literature. In the information management literature, this research provides new insight into the roles that specific information plays in organisations. In the systems thinking literature, this research extends our understanding of the VSM and builds on its powerful diagnostic capability to provide further criteria to aid in the diagnosis of viable organisations. In the information systems literature, this research develops a framework that can be used to help organisations design more effective information systems.

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We study the properties of radiation generated in ultralong fiber lasers and find an interesting link between these optical systems and the theory of weak wave turbulence. Experimental observations strongly suggest that turbulentlike weak interactions between the multitude of laser cavity modes are responsible for practical characteristics of ultralong fiber lasers such as spectra of the output radiation.

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We explore the dynamics of a periodically driven Duffing resonator coupled elastically to a van der Pol oscillator in the case of 1?:?1 internal resonance in the cases of weak and strong coupling. Whilst strong coupling leads to dominating synchronization, the weak coupling case leads to a multitude of complex behaviours. A two-time scales method is used to obtain the frequency-amplitude modulation. The internal resonance leads to an antiresonance response of the Duffing resonator and a stagnant response (a small shoulder in the curve) of the van der Pol oscillator. The stability of the dynamic motions is also analyzed. The coupled system shows a hysteretic response pattern and symmetry-breaking facets. Chaotic behaviour of the coupled system is also observed and the dependence of the system dynamics on the parameters are also studied using bifurcation analysis.

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Understanding a complex network's structure holds the key to understanding its function. The physics community has contributed a multitude of methods and analyses to this cross-disciplinary endeavor. Structural features exist on both the microscopic level, resulting from differences between single node properties, and the mesoscopic level resulting from properties shared by groups of nodes. Disentangling the determinants of network structure on these different scales has remained a major, and so far unsolved, challenge. Here we show how multiscale generative probabilistic exponential random graph models combined with efficient, distributive message-passing inference techniques can be used to achieve this separation of scales, leading to improved detection accuracy of latent classes as demonstrated on benchmark problems. It sheds new light on the statistical significance of motif-distributions in neural networks and improves the link-prediction accuracy as exemplified for gene-disease associations in the highly consequential Online Mendelian Inheritance in Man database. © 2011 Reichardt et al.

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Tumour promoting phorbol esters such as 12-0-tetradecanoylphorbol-13-acetate (TPA) exert a multitude of biological effects on many cellular systems, many of which are believed to be mediated via the activation of the enzyme protein kinase C (PKC). TPA and other biologically active phorbol esters inhibited the proliferation of the A549 human lung carcinoma cell line. However, after 5-6 days culture in the continued presence of the phorbol ester cells began to proliferate at a rate similar to that of untreated cells. Resistance to TPA was lost following subculturing, although subculture in the presence of 10 nM TPA for more than 9 weeks resulted in a more resistant phenotype. The selection of a TPA-resistant subpopulation was not responsible for the observed resistance. The antiproliferative properties of other PKC activators were investigated. Mezerein induced the same antiproliferative effects as TPA but synthetic diacylglycerols (DAGs), the presumed physiological ligands of PKC, exerted only a non-specific cytotoxic influence on growth. Bryostatins 1 and 2 were able to induce transient growth arrest of A549 cells in a manner similar to phorbol esters at nanomolar concentrations, but at higher concentrations blocked both their own antiproliferative action and also that of phorbol esters and mezerein. Fourteen compounds synthesized to mimic features of the phorbol ester pharmacophore and/or DAGs did not mimic the antiproliferative properties of TPA in A549 cells and exerted only a DAG-like non-specific cytotoxicity at high concentrations. The subcellular distribution and activity of PKC was determined following partial purification by non-denaturing polyacrylamide gel electrophoresis. Treatment with TPA, mezerein or bryostatins resulted in a concentration-dependent shift of PKC activity from the cytosol to cellular membranes within 30 min. Significant translocation was not observed on treatment with DAGs. Chronic exposure of cells to TPA caused a time- and concentration dependent down-regulation of functional PKC activity. A complete loss of PKC activity was also observed on treatment with growth-inhibitory concentrations of bryostatins. No PKC activity was detected in cells resistant to the growth-inhibitory influence of TPA. Measurement of intracellular Ca2+ concentrations using A549 cells cultured on Cytodex 1 microcarrier beads revealed that TPA, mezerein and the bryostatins induced a similar rapid rise in intracellular Ca2+ levels.

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The aim of this research project is to compare published history textbooks written for upper-secondary/tertiary study in the U.S. and Spain using Halliday's (1994) Theme/Rheme construct. The motivation for using the Theme/Rheme construct to analyze professional texts in the two languages is two-fold. First of all, while there exists a multitude of studies at the grammatical and phonological levels between the two languages, very little analysis has been carried out in comparison at the level of text, beyond that of comparing L1/L2 student writing. Secondly, thematic considerations allow the analyst to highlight areas of textual organization in a systematic way for purposes of comparison. The basic hypothesis tested here rests on the premise that similarity in the social function of the texts results in similar Theme choice and thematic patterning across languages, barring certain linguistic constraints. The corpus for this study consists of 20 texts: 10 from various history textbooks published in the U.S. and 10 from various history textbooks published in Spain. The texts chosen represent a variety of authors, in order to control for author style or preference. Three overall areas of analysis were carried out, representing Halliday's (1994) three metafunctions: the ideational, the interpersonal and the textual. The ideational analysis shows similarities across the two corpora in terms of participant roles and circumstances as Theme, with a slight difference in participants involved in material processes, which is shown to reflect a minor difference in the construal of the field of history in the two cultures. The textual analysis shows overall similarities with respect to text organization, and the interpersonal analysis shows overall similarities as regards the downplay of discrepant interpretations of historical events as well as a low frequency of interactive textual features, manifesting the informational focus of the texts. At the same time, differences in results amongst texts within each of the corpora demonstrate possible effect of subject matter, in many cases, and individual author style in others. Overall, the results confirm that similarity in content, but above all in purpose and audience, result in texts which show similarities in textual features, setting aside certain grammatical constraints.

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We consider the random input problem for a nonlinear system modeled by the integrable one-dimensional self-focusing nonlinear Schrödinger equation (NLSE). We concentrate on the properties obtained from the direct scattering problem associated with the NLSE. We discuss some general issues regarding soliton creation from random input. We also study the averaged spectral density of random quasilinear waves generated in the NLSE channel for two models of the disordered input field profile. The first model is symmetric complex Gaussian white noise and the second one is a real dichotomous (telegraph) process. For the former model, the closed-form expression for the averaged spectral density is obtained, while for the dichotomous real input we present the small noise perturbative expansion for the same quantity. In the case of the dichotomous input, we also obtain the distribution of minimal pulse width required for a soliton generation. The obtained results can be applied to a multitude of problems including random nonlinear Fraunhoffer diffraction, transmission properties of randomly apodized long period Fiber Bragg gratings, and the propagation of incoherent pulses in optical fibers.

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Non-British migrants and their communities were an integral part of the multifaceted and multicultural nature of the British Empire. Their history, however, goes beyond a clearly delineated narrative of the Empire and includes transnational and truly global dimensions. German migrants and their transnational network creation within the structures of the British Empire, pursued over more than two centuries in a multitude of geographical settings, is the constitutive framework of the present volume. Eight contributions cover economic, cultural, scientific and political themes. The book questions traditional nation-centred narratives of the Empire as an exclusively British undertaking.

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Magnetoencephalography (MEG) can be used to reconstruct neuronal activity with high spatial and temporal resolution. However, this reconstruction problem is ill-posed, and requires the use of prior constraints in order to produce a unique solution. At present there are a multitude of inversion algorithms, each employing different assumptions, but one major problem when comparing the accuracy of these different approaches is that often the true underlying electrical state of the brain is unknown. In this study, we explore one paradigm, retinotopic mapping in the primary visual cortex (V1), for which the ground truth is known to a reasonable degree of accuracy, enabling the comparison of MEG source reconstructions with the true electrical state of the brain. Specifically, we attempted to localize, using a beanforming method, the induced responses in the visual cortex generated by a high contrast, retinotopically varying stimulus. Although well described in primate studies, it has been an open question whether the induced gamma power in humans due to high contrast gratings derives from V1 rather than the prestriate cortex (V2). We show that the beanformer source estimate in the gamma and theta bands does vary in a manner consistent with the known retinotopy of V1. However, these peak locations, although retinotopically organized, did not accurately localize to the cortical surface. We considered possible causes for this discrepancy and suggest that improved MEG/magnetic resonance imaging co-registration and the use of more accurate source models that take into account the spatial extent and shape of the active cortex may, in future, improve the accuracy of the source reconstructions.

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Dipeptidyl peptidase IV (DPP IV) is a widely distributed physiological enzyme that can be found solubilized in blood, or membrane-anchored in tissues. DPP IV and related dipeptidase enzymes cleave a wide range of physiological peptides and have been associated with several disease processes including Crohn's disease, chronic liver disease, osteoporosis, multiple sclerosis, eating disorders, rheumatoid arthritis, cancer, and of direct relevance to this review, type 2 diabetes. Here, we place particular emphasis on two peptide substrates of DPP IV with insulin-releasing and antidiabetic actions namely, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). The rationale for inhibiting DPP IV activity in type 2 diabetes is that it decreases peptide cleavage and thereby enhances endogenous incretin hormone activity. A multitude of novel DPP IV inhibitor compounds have now been developed and tested. Here we examine the information available on DPP IV and related enzymes, review recent preclinical and clinical data for DPP IV inhibitors, and assess their clinical significance.

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The vast diversity of S100 proteins has demonstrated a multitude of biological correlations with cell growth, cell differentiation and cell survival in numerous physiological and pathological conditions in all cells of the body. This review summarises some of the reported regulatory functions of S100 proteins (namely S100A1, S100A2, S100A4, S100A6, S100A7, S100A8/S100A9, S100A10, S100A11, S100A12, S100B and S100P) on cellular migration and invasion, established in both culture and animal model systems and the possible mechanisms that have been proposed to be responsible. These mechanisms involve intracellular events and components of the cytoskeletal organisation (actin/myosin filaments, intermediate filaments and microtubules) as well as extracellular signalling at different cell surface receptors (RAGE and integrins). Finally, we shall attempt to demonstrate how aberrant expression of the S100 proteins may lead to pathological events and human disorders and furthermore provide a rationale to possibly explain why the expression of some of the S100 proteins (mainly S100A4 and S100P) has led to conflicting results on motility, depending on the cells used. © 2013 Springer Basel.

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It is a great pleasure to be Guest Editor for this issue – I hope that the papers which are included will be stimulating and support you in your ongoing research activities. A number of guiding principles were adopted in selecting the papers for inclusion in this issue. Firstly, the papers cover a wide range of logistics and supply chain management (SCM) topics. This is a reflection of the evolution of the field in recent years. In terms of the “buy-make-store-move-sell” model of SCM all the main constituent areas are addressed. Secondly, it is important that the conference issue of this Journal reflects the emphasis and content of the conference itself. I have tried to achieve this in terms of the papers included. One interesting point to note is that outsourcing is a theme which is a major issue in a number of papers. This reflects the increasing importance of this issue to organisations of all kinds and sizes. Economic globalisation and the trend towards vertical disintegration of supply chain architectures have sharpened the focus on outsourcing as a key element of supply chain strategy. The need to move beyond the notion that sourcing of certain activities can be some kind of panacea in evident from the relevant contributions. Thirdly, the LRN Annual Conference has become a more international event in recent years...the number of delegates and papers presented from outside the UK has continued to grow. The papers collected in this issue reflect this internationalization. Two papers are worthy of particular comment from an LRN perspective. The contribution by Jaafar and Rafiq has been developed from the submission which won the best paper prize at the LRN 2004 event. The paper by Pettit and Beresford is based on research which was supported by LRN seed corn funding. It was developed form the final report on this work submitted to CITL (UK) via the LRN. The seed corn funding is an important mechanism whereby the LRN supports research in innovative aspects of logistics in UK universities. In many ways, the LRN2004 event in Dublin seems like a long time ago. From my point of view it was one of the most professionally rewarding activities in which I have been involved in my career. It was a time to meet old friends and new and to keep abreast of the multitude of interesting projects being undertaken in over 20 countries. There are too many people to thank for the smooth running of the event. However, my colleague John Mee does warrant a special mention. His logistical skills were seriously put to the test in the weeks and months leading up to September 9th. 2004. I want to acknowledge his particular contribution to the success of the event. Since then we have had the 2005 event at the University of Plymouth. This was again a great opportunity to network with colleagues and many congratulations are due to John Dinwoodie and his team. We now look forward to LRN 2006 in Newcastle...form my part I hope and trust that this issue provides some useful perspectives and insights into the range of topics addressed.

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This book is concerned with the day-to-day realities of doing social science research. It is based upon the reflections and experiences of a wide range of established social researchers, the majority of whom undertake research in the field of health care. By drawing upon their anecdotal accounts of setting up research projects, negotiating access, collecting and analysing data, and disseminating findings, the book highlights a multitude of practical and ethical complexities involved in the conduct of empirically based research. It delineates the emotional, social and cultural factors involved at all stages of the research process, and sets this delineation in the context of wider debates about the relationship between research methods and research ethics.

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Behavioural studies have shown that dyslexics are a heterogeneous population and between-group comparisons are thus inadequate. Some subjects do not develop dyslexia despite having a deficit implicated in this disorder, which points to protective factors. Dyslexia co-occurs with ADHD, DCD, SLI, and SSD, so that future behavioural studies will need to screen and/or statistically control for other disorders. Studies of multiple cases of DPs with other developmental disorders are necessary. Neuroimaging findings show structural and/or functional brain abnormalities in language areas, V5/MT and the cerebellum. Future neuroimaging studies need to investigate the whole reading network and multiple cases. Six dyslexia risk genes have been found, mostly involved in neural migration, which may suggest dyslexia is a deficit of neuronal migration. However, it is not clear how these genes can restrict migration to specific brain areas. As a complex and heterogeneous disorder, dyslexia is likely to be associated with several mutated genes. ADHD and SSD are characterised by genetic risk factors which are partially shared with dyslexia, resulting in comorbidity. Future genetic studies need to focus on identifying other risk genes and pleiotropic genes involved in comorbidities, and linking genotypes implicated in dyslexia with brain structure. Any theory of dyslexia needs to take into account a multitude of risk and protective factors across behavioural, neural and genetic domains.