3,849 research outputs found
Externalities and Growth
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
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
The classical âintegration processâ 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 governmentsâ monopoly in the representation of national interests of
the Unionâs 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
Purpose: The main aim of this research is to analyzed the role of the European srtuctural funds in the region of Galicia, Spain. In 1980âs, 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
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
A tanulmĂĄny felvĂĄzolja a terĂŒletfejlesztĂ©si Ă©s a verseny-, illetve iparpolitikĂĄnak a metszetĂ©ben elhelyezkedĆ francia versenykĂ©pessĂ©gi pĂłlusok kialakulĂĄsĂĄnak elĆzmĂ©nyeit, elmĂ©leti hĂĄtterĂ©t, Ă©s az alig egy Ă©vtizedes
mĂșltra visszatekintĆ gyakorlati tapasztalatok összegzĂ©sĂ©re vĂĄllalkozik. A versenykĂ©pessĂ©gi pĂłlusok az innovĂĄciĂłs szereplĆk hĂĄlĂłzatos kapcsolataira Ă©pĂŒlnek, fejlĆdĂ©sĂŒket a szereplĆk közti egyĂŒttmƱködĂ©s minĆsĂ©ge alakĂtja. Miközben a teljesĂtmĂ©ny-szemlĂ©letƱ politikĂĄk a legdinamikusabban fejlĆdĆ rĂ©giĂłkra összpontosĂtanak az orszĂĄg eurĂłpai Ă©s globĂĄlis pozĂciĂłjĂĄt szem elĆtt tartva, Ă©s a pĂłlusok esetĂ©ben is a legĂgĂ©retesebb csĂșcsipari ĂĄgazatok tĂĄmogatĂĄsĂĄt szorgalmazzĂĄk, a közel fĂ©l Ă©vszĂĄzados mĂșltĂș egyenlĆsĂtĆ cĂ©lzatĂș terĂŒletfejlesztĂ©si politikĂĄk cĂ©ljai a pĂłlusok nagy szĂĄmĂĄval Ă©s a hagyomĂĄnyos, Ă©rettebb ĂĄgazatok tĂĄmogatĂĄsĂĄval realizĂĄlĂłdnak. A kettĆs cĂ©lkitƱzĂ©s egyidejƱleg a pĂłlusprogram esetĂ©ben is nehezen teljesĂthetĆ, de mindmĂĄig jelen van az orszĂĄg jövĆjĂ©t meghatĂĄrozĂł terĂŒletpolitikai vitĂĄkban
Water quality and quantity assessment of pervious pavements performance in experimental car park areas
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 âLaboratorio Caminos Santanderâ 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
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. Twentyâtwo patients with lower extremity paresis were exposed to realâtime 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 leftâright foot asymmetry. We observed that augmenting lowâfrequency 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 heelâground exerted force. By contrast, augmenting highâfrequency 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 predictedâactual 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
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. Littmannâs 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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Suitability of equivalent linear soil models for analysing the seismic response of a concrete tunnel
Current methods of analysis for the seismic response of tunnels rely on linear elastic soil constitutive behaviour. This has obvious benefits in terms of minimising the number of soil parameters required and the complexity compared to more sophisticated soil models. However, it has recently become possible to parameterise sophisticated soil models using only routine data from boreholes or in-situ testing. This paper will therefore review the effectiveness of seismic analyses using an equivalent linear soil constitutive model, by comparison of 2D Finite Element simulations with those using an advanced non-linear elastic model with isotropic hardening plasticity. In the elastic case, the parameters have been estimated using Equivalent-linear Earthquake site Response Analyses software (EERA) and consideration will be given to the amount of sublayering that is required to match the variation of soil properties with depth. The tunnel considered is of horseshoe shape and sprayed concrete construction (New Austrian Tunnelling Method), based on metro tunnels in Santiago, Chile, subjected to the Llolleo ground motion from the 1985 Valparaiso Earthquake. The results will focus the differences in the induced structural forces within the tunnel lining and modification to the ground motion in the near-field of the tunnel, and discuss the implications of this for tunnel design
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