Korea and the BICs (Brazil, India and China) : catching up experiences

This paper tests a neo-Schumpeterian model with industry-level data to analyze how Brazil, India, and China are catching up with South Korea’s technological frontier in a globalized world. The paper validates Aghion et al.’s inverted-U hypothesis that industries that are closer to the technological frontier innovate to escape competition while longer distances discourage innovating. It suggests that for effective catching up, distance-shortening (or innovation-enhancing) policies may be a necessary complement to liberalization. South Korea and China combined a variety of distance-shortening policies with financial subsidies to promote high tech industries and an export-led growth strategy. Post-liberalization, they leveraged swift competition to spur catch-up. In comparison, Brazil, which was as rich as South Korea, and India, which was as rich as China in 1980, are catching up more slowly. Import-substitution industrialization strategies saddled Brazil and India with a large anti-export bias, and unfocused attention to innovation-enhancing policies dampened global competitiveness. Post liberalization, many of their industries were too far behind the technological frontier to effectively benefit from competition. The catch-up experiences of Brazil, India, and China with South Korea illustrate that distance from the technological frontier matters and that the design of country-specific distance- shortening policies can be an important complement to trade liberalization in promoting catching up with richer countries.Labor Policies,Economic Theory&Research,Water and Industry,E-Business,Knowledge for Development

Angle-resolved cathodoluminescence imaging polarimetry

Cathodoluminescence spectroscopy (CL) allows characterizing light emission in bulk and nanostructured materials and is a key tool in fields ranging from materials science to nanophotonics. Previously, CL measurements focused on the spectral content and angular distribution of emission, while the polarization was not fully determined. Here we demonstrate a technique to access the full polarization state of the cathodoluminescence emission, that is the Stokes parameters as a function of the emission angle. Using this technique, we measure the emission of metallic bullseye nanostructures and show that the handedness of the structure as well as nanoscale changes in excitation position induce large changes in polarization ellipticity and helicity. Furthermore, by exploiting the ability of polarimetry to distinguish polarized from unpolarized light, we quantify the contributions of different types of coherent and incoherent radiation to the emission of a gold surface, silicon and gallium arsenide bulk semiconductors. This technique paves the way for in-depth analysis of the emission mechanisms of nanostructured devices as well as macroscopic media.Comment: 8 figures. Includes supplementary informatio

Realització d'un portal web d'oci i cultura del Maresme

La comarca del Maresme és molt activa en matèria d’oci i cultura, però els mitjans locals només es fan ressò del que es fa a la seva localitat, i aquells que tenen un caràcter més comarcal opten per donar més importància a temes polítics o esportius, deixant una mica de banda la cultura i l’oci. Els mitjans de comunicació generalistes, ja siguin digital o en format paper, han de fer una selecció de les noticies que succeeixen i moltes queden fora. A la comarca no hi ha cap portal cultural que es faci ressò de tots els actes, events i espectacles culturals que es duen a terme per entitats, institucions, empreses i associacions. La idea principal del meu Projecte Final de Carrera és omplir aquest buit i crear un portal web d’oci i cultura de la comarca del Maresme amb articles d’allò del que es fa i s’ha fet, crítiques, enriquit amb fotografies i vídeos

Spatial entanglement of paired photons generated in cold atomic ensembles

Cold atomic ensembles can mediate the generation of entanglement between pairs of photons. Photons with specific directions of propagation are detected, and the entanglement can reside in any of the degrees of freedom that describe the whole quantum state of the photons: polarization, spatial shape or frequency. We show that the direction of propagation of the generated photons determines the spatial quantum state of the photons and therefore, the amount of entanglement generated. When photons generated in different directions are combined, this spatial distinguishing information can degrade the quantum purity of the polarization or frequency entanglement.Comment: 5 pages, 4 figures. Submitted to Phys. Rev. A.; one figure (Fig. 3) was added, typos and labels in figure 2 were correcte

Rusty microglia: trainers of innate immunity in Alzheimer's disease

Alzheimer's disease, the most common form of dementia, is marked by progressive cognitive and functional impairment believed to reflect synaptic and neuronal loss. Recent preclinical data suggests that lipopolysaccharide (LPS)-activated microglia may contribute to the elimination of viable neurons and synapses by promoting a neurotoxic astrocytic phenotype, defined as A1. The innate immune cells, including microglia and astrocytes, can either facilitate or inhibit neuroinflammation in response to peripherally applied inflammatory stimuli, such as LPS. Depending on previous antigen encounters, these cells can assume activated (trained) or silenced (tolerized) phenotypes, augmenting or lowering inflammation. Iron, reactive oxygen species (ROS), and LPS, the cell wall component of gram-negative bacteria, are microglial activators, but only the latter can trigger immune tolerization. In Alzheimer's disease, tolerization may be impaired as elevated LPS levels, reported in this condition, fail to lower neuroinflammation. Iron is closely linked to immunity as it plays a key role in immune cells proliferation and maturation, but it is also indispensable to pathogens andmalignancies which compete for its capture. Danger signals, including LPS, induce intracellular iron sequestration in innate immune cells to withhold it from pathogens. However, excess cytosolic iron increases the risk of inflammasomes' activation, microglial training and neuroinflammation. Moreover, it was suggested that free iron can awaken the dormant central nervous system (CNS) LPS-shedding microbes, engendering prolonged neuroinflammation that may override immune tolerization, triggering autoimmunity. In this review, we focus on iron-related innate immune pathology in Alzheimer's disease and discuss potential immunotherapeutic agents for microglial de-escalation along with possible delivery vehicles for these compounds

Backaction in metasurface etalons

We consider the response of etalons created by a combination of a conventional mirror and a metasurface, composed of a periodic lattice of metal scatterers with a resonant response. This geometry has been used previously for perfect absorption, in so-called Salisbury screens, and for hybridization of localized plasmons with Fabry-Perot resonances. The particular aspect we address is if one can assume an environment-independent reflectivity for the metasurface when calculating the reflectivity of the composite system, as in a standard Fabry-Perot analysis, or whether the fact that the metasurface interacts with its own mirror image renormalizes its response. Using lattice sum theory, we take into account all possible retarded dipole-dipole interactions of scatterers in the metasurface amongst each other, and through the mirror. We show that while a layer-by-layer Fabry-Perot formalism captures the main qualitative features of metasurface etalons, in fact the mirror modifies both the polarizability and reflectivity of the metasurface in a fashion that is akin to Drexhage's modification of the radiative properties of a single dipole.Comment: 10 pages, 5 figure