Compact focusing grating couplers for silicon horizontal slot waveguides

In this Letter, we present the design, simulation (2D and 3D), fabrication, and experimental characterization of compact and fully etched focusing gratings for a horizontal slot waveguide based on a silicon nitride layer sandwiched between amorphous silicon and a silicon-on-insulator. The measured coupling losses are about 4 dB with a 3 dB bandwidth of 38 nm. The fully etched configuration allows the fabrication in a single lithography step.Ministerio de Economia y Competitividad (MINECO) (TEC2012-38540-C02-02, TEC2016-76849-C2-2-R); Generalitat Valenciana (NANOMET PLUS -PROMETEOII/2014/034).Larrea-Luzuriaga, RA.; Gutiérrez Campo, AM.; Hurtado Montañés, J.; Ramirez, JM.; Garrido, B.; Sanchis Kilders, P. (2017). Compact focusing grating couplers for silicon horizontal slot waveguides. Optics Letters. 42(3):490-493. https://doi.org/10.1364/OL.42.000490S49049342

HIV/AIDS epidemiology, pathogenesis, prevention, and treatment.

The HIV-1 pandemic is a complex mix of diverse epidemics within and between countries and regions of the world, and is undoubtedly the defining public-health crisis of our time. Research has deepened our understanding of how the virus replicates, manipulates, and hides in an infected person. Although our understanding of pathogenesis and transmission dynamics has become more nuanced and prevention options have expanded, a cure or protective vaccine remains elusive. Antiretroviral treatment has transformed AIDS from an inevitably fatal condition to a chronic, manageable disease in some settings. This transformation has yet to be realised in those parts of the world that continue to bear a disproportionate burden of new HIV-1 infections and are most affected by increasing morbidity and mortality. This Seminar provides an update on epidemiology, pathogenesis, treatment, and prevention interventions pertinent to HIV-1

Lealtad a la marca: tipología, caracterización, y variables potencialmente relacionadas. contrastación empírica para la categoría cervezas en la ciudad de Guayaquil

La idea del desarrollo del presente tema nace de la necesidad de determinar las diferentes variables que influyen en la lealtad de los consumidores a una marca y como la implicación, la deliberación, la diferenciación, la satisfacción y los costes de cambio influyen en el proceso de decisión de la compra, dirigida a hombres y mujeres consumidores activos de cerveza para lograr mejores resultados. Se evaluó mediante una investigación concluyente y causal, también se realizó una técnica de muestreo probabilístico simple donde este estudio arrojó las variables que participan en la elección de los consumidores, teniendo como marco de muestra un procedimiento aleatorio

Metallophilic Au( i

1,4,7-Triazacyclononane (TACN) has been used for the first time to support Au(i)⋯M [M = Tl(i), Ag(i)] metallophilic interactions in the formation of heteronuclear gold(i) complexes having luminescence properties. The compounds {[{Au(C6Cl5)2}Tl(TACN)]2}n (1), [{Au(C6F5)2}Tl(TACN)] (2), [{Au(C6Cl5)2}Ag(TACN)] (3), and [{Au(C6F5)2}{Ag(TACN)}2Au(C6F5)2] (4) have been synthesized by reacting TACN and the polymeric starting organometallic gold(i) compounds [{Au(C6X5)2}M]n (M = Ag(i), Tl(i); X = Cl, F) in a 1 : 1 molar ratio, in THF. 1, 3 and 4 have also been structurally characterized and their optical properties explained on the basis of their structural features with the support of TD-DFT calculations

Influence of additives on recycled polymer blends

Polymer systems based on polymer waste offer promising way to increase recycling in the society. Since fillers play a major role in determining the properties and behavior of polymer composites, recycled polymers can also be combined with fillers to enhance the stiffness and thermal stability. In this study, blends of recycled polyethylene and recycled polypropylene with mica and glass fiber were prepared by melt blending technique. The effect of the particle loading, filler type, and filler–matrix interaction on thermal degradation and thermal transition of processed systems were investigated. Thermogravimetric analysis, differential thermogravimetric analysis, and differential scanning calorimetry were used in this investigation. Comparative analysis shows that both fillers produced different effects on thermal properties of the processed systems. These results were confirmed by calculating the activation energy for thermal degradation and thermal transition using Kissinger and Flynn–Wall expressions