39,196 research outputs found

    Urban growth drivers in a Europe of sticky people and implicit boundaries

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    We investigate urban GDP pc growth across the EU12 using data for functionally defined cities - rather than administrative regions. We test hypotheses on the role of human capital, EU integration and fragmentation of urban government and explore spatial dependence and mechanisms of spatial interaction. Results are acceptable on standard econometric tests without measures of spatial interaction but there is spatial dependence. If variables reflecting spatial adjustment are included, they are statistically significant and eliminate spatial dependence. Not only do the results now provide consistent estimates of parameters, they also support relevant theoretical insights and show national borders are still significant barriers to economic adjustment. People in Europe are sticky so it is unreasonable to assume spatial disparities will disappear. Our findings also imply that cities in Europe form national rather than a single continental system

    Hemispheric lateralisation and immune function: A systematic review of human research

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    This is the post-print version of the final paper published in Journal of Neuroimmunology. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2011 Elsevier B.V.Past studies examined relationships between hemispheric lateralisation (HL) and immune system functioning. However, there has been no up-dated systematic review of this research area. This article reviews relevant published studies, evaluates study quality and effect sizes. Eleven studies were selected: three revealing a relationship between weaker left hemisphere function and poorer immune function, three describing a relationship between weaker right hemisphere function and stronger immune functioning, and five describing both relationships. Mean effect-size of the studies was r = 0.536 (range 0.280–0.866). Collectively, studies point at left-HL and stronger immunity relationships. Limitations, mechanisms and clinical implications are discussed

    Does FDI promote regional development? Evidence from local and regional productivity spillovers in Greece

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    Studies on the productivity spillovers of FDI have concentrated on the nationalsectoral level. As a result, little is known about the impact of FDI on absolute and relative regional economic performance. In this paper we examine this issue by relying on a unique dataset of over 20,000 Greek firms for the period 2002-2006 covering all sectors of economic activity. We examine the spatial distribution of foreign-owned firms in the country and analyse the effect that their presence – at the local, regional and national levels – has on the productivity of domestic firms. We find strong evidence suggesting that foreignowned firms self-select into regions and sectors of high productivity. Net of this selection effect, the impact of foreign presence on domestic productivity is negative – although at the very local level some positive spillover effects are identifiable. The bulk of the effects concentrate in non-manufacturing activities, high-tech sectors, and medium-sized high-productivity firms. Importantly, this effect is not constant across space however. Productivity spillovers tend to be negative in the regions hosting the main urban areas in the country but positive in smaller and more peripheral regions. In this way, despite the tendency of FDI to concentrate in a limited number of areas within the country – those of the highest level of development – the externalities that FDI activity generates to the local economies appear to be of a rather equilibrating character. Key words: regional development, FDI, productivity spillovers, Greece, spatial heterogeneity

    Single DNA conformations and biological function

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    From a nanoscience perspective, cellular processes and their reduced in vitro imitations provide extraordinary examples for highly robust few or single molecule reaction pathways. A prime example are biochemical reactions involving DNA molecules, and the coupling of these reactions to the physical conformations of DNA. In this review, we summarise recent results on the following phenomena: We investigate the biophysical properties of DNA-looping and the equilibrium configurations of DNA-knots, whose relevance to biological processes are increasingly appreciated. We discuss how random DNA-looping may be related to the efficiency of the target search process of proteins for their specific binding site on the DNA molecule. And we dwell on the spontaneous formation of intermittent DNA nanobubbles and their importance for biological processes, such as transcription initiation. The physical properties of DNA may indeed turn out to be particularly suitable for the use of DNA in nanosensing applications.Comment: 53 pages, 45 figures. Slightly revised version of a review article, that is going to appear in the J. Comput. Theoret. Nanoscience; some typos correcte

    Quantum learning: optimal classification of qubit states

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    Pattern recognition is a central topic in Learning Theory with numerous applications such as voice and text recognition, image analysis, computer diagnosis. The statistical set-up in classification is the following: we are given an i.i.d. training set (X1,Y1),...(Xn,Yn)(X_{1},Y_{1}),... (X_{n},Y_{n}) where XiX_{i} represents a feature and Yi∈{0,1}Y_{i}\in \{0,1\} is a label attached to that feature. The underlying joint distribution of (X,Y)(X,Y) is unknown, but we can learn about it from the training set and we aim at devising low error classifiers f:X→Yf:X\to Y used to predict the label of new incoming features. Here we solve a quantum analogue of this problem, namely the classification of two arbitrary unknown qubit states. Given a number of `training' copies from each of the states, we would like to `learn' about them by performing a measurement on the training set. The outcome is then used to design mesurements for the classification of future systems with unknown labels. We find the asymptotically optimal classification strategy and show that typically, it performs strictly better than a plug-in strategy based on state estimation. The figure of merit is the excess risk which is the difference between the probability of error and the probability of error of the optimal measurement when the states are known, that is the Helstrom measurement. We show that the excess risk has rate n−1n^{-1} and compute the exact constant of the rate.Comment: 24 pages, 4 figure

    Provision of foot health services for people with rheumatoid arthritis in New South Wales: a web-based survey of local podiatrists

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    Background: It is unclear if podiatric foot care for people with rheumatoid arthritis (RA) in New South Wales (NSW) meets current clinical recommendations. The objective of this study was to survey podiatrists' perceptions of the nature of podiatric foot care provision for people who have RA in NSW.Methods: An anonymous, cross-sectional survey with a web-based questionnaire was conducted. The survey questionnaire was developed according to clinical experience and current foot care recommendations. State registered podiatrists practising in the state of NSW were invited to participate. The survey link was distributed initially via email to members of the Australian Podiatry Association (NSW), and distributed further through snowballing techniques using professional networks. Data was analysed to assess significant associations between adherence to clinical practice guidelines, and private/public podiatry practices.Results: 86 podiatrists participated in the survey (78% from private practice, 22% from public practice). Respondents largely did not adhere to formal guidelines to manage their patients (88%). Only one respondent offered a dedicated service for patients with RA. Respondents indicated that the primary mode of accessing podiatry was by self-referral (68%). Significant variation was observed regarding access to disease and foot specific assessments and treatment strategies. Assessment methods such as administration of patient reported outcome measures, vascular and neurological assessments were not conducted by all respondents. Similarly, routine foot care strategies such as prescription of foot orthoses, foot health advice and footwear were not employed by all respondents.Conclusions: The results identified issues in foot care provision which should be explored through further research. Foot care provision in NSW does not appear to meet the current recommended standards for the management of foot problems in people who have RA. Improvements to foot care could be undertaken in terms of providing better access to examination techniques and treatment strategies that are recommended by evidence based treatment paradigms. © 2013 Hendry et al.; licensee BioMed Central Ltd

    An HST/ACS investigation of the spatial and chemical structure and sub-structure of NGC 891, a Milky Way analogue

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    We present a structural analysis of NGC891, an edge-on galaxy that has long been considered to be an analogue of the Milky Way. Using starcounts derived from deep HST/ACS images, we detect the presence of a thick disk component in this galaxy with vertical scale height 1.44+/-0.03 kpc and radial scale length 4.8+/-0.1 kpc, only slightly longer than that of the thin disk. A stellar spheroid with a de Vaucouleurs-like profile is detected from a radial distance of 0.5 kpc to the edge of the survey at 25 kpc; the structure appears to become more flattened with distance, reaching q = 0.50 in the outermost halo region probed. The halo inside of 15 kpc is moderately metal-rich (median [Fe/H] ~ -1.1) and approximately uniform in median metallicity. Beyond that distance a modest chemical gradient is detected, with the median reaching [Fe/H] ~ -1.3 at 20 kpc. We find evidence for subtle, but very significant, small-scale variations in the median colour and density over the halo survey area. We argue that the colour variations are unlikely to be due to internal extinction or foreground extinction, and reflect instead variations in the stellar metallicity. Their presence suggests a startling conclusion: that the halo of this galaxy is composed of a large number of incompletely-mixed sub-populations, testifying to its origin in a deluge of small accretions.Comment: 21 pages, 16 figures, accepted for publication in MNRA
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