3,449 research outputs found

    Externalities and Growth

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    Externalities play a central role in most theories of economic growth. We argue that international externalities, in particular, are essential for explaining a number of empirical regularities about growth and development. Foremost among these is that many countries appear to share a common long run growth rate despite persistently different rates of investment in physical capital, human capital, and research. With this motivation, we construct a hybrid of some prominent growth models that have international knowledge externalities. When calibrated, the hybrid model does a surprisingly good job of generating realistic dispersion of income levels with modest barriers to technology adoption. Human capital and physical capital contribute to income differences both directly (as usual), and indirectly by boosting resources devoted to technology adoption. The model implies that most of income above subsistence is made possible by international diffusion of knowledge.

    New Economic Geography And Educational Attainment Levels In The European Union

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    In this paper a New Economic Geography model is used to analyse the distribution of educational attainment levels in the European Union. The results show that educational attainment levels decrease with distance to large consumer markets, proving that the theoretical predictions of the model are verified empirically

    European constitutional political economy : enlargement and the crisis of institutional system

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    The classical “integration process” has reached a critical point and constitutional limits, which make a qualitative change of importance in the system of community government indispensable. Our paper is based on an analysis of the constitutional choices of citizens and governments using a political-economic model, whose main conclusion centres on the need for breaking the central governments’ monopoly in the representation of national interests of the Union’s member states, both at a constitutional level (reform of treaties) and in the institutional balance (decision making).peer-reviewe

    The long-term role of EU structural funds in the accessibility of peripheral regions : the case of Galicia in the period 1989-2013

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    Purpose: The main aim of this research is to analyzed the role of the European srtuctural funds in the region of Galicia, Spain. In 1980’s, Galicia was a peripheral region with poor external accessibility and internal connectivity with a lacked efficient transport infrastructure. Design/Methodology/Approach: The evaluation methodology used integrates documentary sources depending on the availability in each programme period (official documents, evaluation reports, basic statistics and papers). Findings: One of the most important lessons learned by the Structural Funds from the Galician experience relates to the effect of accessibility in peripheral lagging regions. Practical Implications: Enhanced accessibility to a large integrated market is a good way to boost structural adjustment and productivity. Originality/Value: The combination of the strong investment policy and increased competition in the single European market has been demonstrated as a powerful vehicle for economic development and convergence.peer-reviewe

    Polymer brush collapse under shear flow

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    Shear responsive surfaces offer potential advances in a number of applications. Surface functionalisation using polymer brushes is one route to such properties, particularly in the case of entangled polymers. We report on neutron reflectometry measurements of polymer brushes in entangled polymer solutions performed under controlled shear, as well as coarse-grained computer simulations corresponding to these interfaces. Here we show a reversible and reproducible collapse of the brushes, increasing with the shear rate. Using two brushes of greatly different chain lengths and grafting densities, we demonstrate that the dynamics responsible for the structural change of the brush are governed by the free chains in solution rather than the brush itself, within the range of parameters examined. The phenomenon of the brush collapse could find applications in the tailoring of nanosensors, and as a way to dynamically control surface friction and adhesion

    TerĂŒletfejlesztĂ©s vagy iparpolitika?: A francia versenykĂ©pessĂ©gi pĂłlus program tapasztalatai

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    A tanulmĂĄny felvĂĄzolja a terĂŒletfejlesztĂ©si Ă©s a verseny-, illetve iparpolitikĂĄnak a metszetĂ©ben elhelyezkedƑ francia versenykĂ©pessĂ©gi pĂłlusok kialakulĂĄsĂĄnak elƑzmĂ©nyeit, elmĂ©leti hĂĄtterĂ©t, Ă©s az alig egy Ă©vtizedes mĂșltra visszatekintƑ gyakorlati tapasztalatok összegzĂ©sĂ©re vĂĄllalkozik. A versenykĂ©pessĂ©gi pĂłlusok az innovĂĄciĂłs szereplƑk hĂĄlĂłzatos kapcsolataira Ă©pĂŒlnek, fejlƑdĂ©sĂŒket a szereplƑk közti egyĂŒttmƱködĂ©s minƑsĂ©ge alakĂ­tja. Miközben a teljesĂ­tmĂ©ny-szemlĂ©letƱ politikĂĄk a legdinamikusabban fejlƑdƑ rĂ©giĂłkra összpontosĂ­tanak az orszĂĄg eurĂłpai Ă©s globĂĄlis pozĂ­ciĂłjĂĄt szem elƑtt tartva, Ă©s a pĂłlusok esetĂ©ben is a legĂ­gĂ©retesebb csĂșcsipari ĂĄgazatok tĂĄmogatĂĄsĂĄt szorgalmazzĂĄk, a közel fĂ©l Ă©vszĂĄzados mĂșltĂș egyenlƑsĂ­tƑ cĂ©lzatĂș terĂŒletfejlesztĂ©si politikĂĄk cĂ©ljai a pĂłlusok nagy szĂĄmĂĄval Ă©s a hagyomĂĄnyos, Ă©rettebb ĂĄgazatok tĂĄmogatĂĄsĂĄval realizĂĄlĂłdnak. A kettƑs cĂ©lkitƱzĂ©s egyidejƱleg a pĂłlusprogram esetĂ©ben is nehezen teljesĂ­thetƑ, de mindmĂĄig jelen van az orszĂĄg jövƑjĂ©t meghatĂĄrozĂł terĂŒletpolitikai vitĂĄkban

    Water quality and quantity assessment of pervious pavements performance in experimental car park areas

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    Pervious pavements have become one of the most used sustainable urban drainage system (SUDS) techniques in car parks. This research paper presents the results of monitoring water quality from several experimental car park areas designed and constructed in Spain with bays made of interlocking concrete block pavement, porous asphalt, polymer-modified porous concrete and reinforced grass with plastic and concrete cells. Moreover, two different sub-base materials were used (limestone aggregates and basic oxygen furnace slag). This study therefore encompasses the majority of the materials used as permeable surfaces and sub-base layers all over the world. Effluent from the test bays was monitored for dissolved oxygen, pH, electric conductivity, total suspended solids, turbidity and total petroleum hydrocarbons in order to analyze the behaviour shown by each combination of surface and sub-base materials. In addition, permeability tests were undertaken in all car parks using the ‘Laboratorio Caminos Santander’ permeameter and the Cantabrian Portable Infiltrometer. All results are presented together with the influence of surface and sub-base materials on water quality indicators using bivariate correlation statistical analysis at a confidence level of 95%. The polymer-modified porous concrete surface course in combination with limestone aggregate sub-base presented the best performance

    Enriching footsteps sounds in gait rehabilitation in chronic stroke patients: a pilot study

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    In the context of neurorehabilitation, sound is being increasingly applied for facilitating sensorimotor learning. In this study, we aimed to test the potential value of auditory stimulation for improving gait in chronic stroke patients by inducing alterations of the frequency spectra of walking sounds via a sound system that selectively amplifies and equalizes the signal in order to produce distorted auditory feedback. Twenty‐two patients with lower extremity paresis were exposed to real‐time alterations of their footstep sounds while walking. Changes in body perception, emotion, and gait were quantified. Our results suggest that by altering footsteps sounds, several gait parameters can be modified in terms of left–right foot asymmetry. We observed that augmenting low‐frequency bands or amplifying the natural walking sounds led to a reduction in the asymmetry index of stance and stride times, whereas it inverted the asymmetry pattern in heel–ground exerted force. By contrast, augmenting high‐frequency bands led to opposite results. These gait changes might be related to updating of internal forward models, signaling the need for adjustment of the motor system to reduce the perceived discrepancies between predicted–actual sensory feedbacks. Our findings may have the potential to enhance gait awareness in stroke patients and other clinical conditions, supporting gait rehabilitation

    Variations of OCT measurements corrected for the magnification effect according to axial length and refractive error in children

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    The aim of this paper was to examine the distribution of macular, retinal nerve fiber layer (RNFL) thickness and optic disc parameters of myopic and hyperopic eyes in comparison with emmetropic control eyes and to investigate their variation according to axial length (AL) and spherical equivalent (SE) in healthy children. Methods: This study included 293 pairs of eyes of 293 children (145 boys and 148 girls), ranging in age from 6 to 17 years. Subjects were divided according to SE in control (emmetropia, 99 children), myopia (100 children) and hyperopia (94 children) groups and according to axial AL in 68 short ((Formula presented.)22.00(Formula presented.)mm, 68), medium (from (Formula presented.)22.00(Formula presented.)mm to 25.00(Formula presented.)mm, 189) and long eyes ((Formula presented.)25.00(Formula presented.)mm, 36). Macular parameters, RNFL thickness and optic disc morphology were assessed by the CirrusTM HD-OCT. AL was measured using the IOL-Master system. Littmann’s formula was used for calculating the corrected AL-related ocular magnification. Results: Mean age ((Formula presented.)(Formula presented.)SD) was 10.84(Formula presented.)(Formula presented.)(Formula presented.)3.05 years; mean ((Formula presented.)(Formula presented.)SD) SE was (Formula presented.)0.14(Formula presented.)(Formula presented.)(Formula presented.)0.51 D (range from (Formula presented.)8.75 to (Formula presented.)8.25 D) and mean AL ((Formula presented.)(Formula presented.)SD) was 23.12(Formula presented.)(Formula presented.)(Formula presented.)1.49. Average RNFL thickness, average macular thickness and macular volume decreased as AL and myopia increased. No correlations between AL/SE and optic disc parameters were found after correcting for magnification effect. Conclusions: AL and refractive error affect measurements of macular and RNFL thickness in healthy children. To make a correct interpretation of OCT measurements, ocular magnification effect should be taken into account by clinicians or OCT manufacturers.Postprint (published version
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