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Spatial modulation of the electromagnetic energy transfer by excitation of graphene waveguide surface plasmons
2019
We theoretically study the electromagnetic energy transfer between donor and acceptor molecules near a graphene waveguide (WG). The surface plasmons (SPs) supported by the structure provide decay channels which lead to an improvement in the energy transfer rate when the donor and acceptor are localized on the same side or even on opposite sides of the WG. The modification of the energy transfer rate compared to its value in absence of the WG are calculated by deforming the integration path into a suitable path in the complex plane. Our results show that this modification is dramatically enhanced when the symmetric and antisymmetric SPs are excited. Notable effects on the spatial dependence …
Desafio de dos vecinos madrideños [sic], que acaso se verificara el viernes 24 del corriente mes de abril de este año de 1812 en la plaza de San Anto…
Signat a la fi: G.A.X, inicials de Guillermo Atanasio Jaramillo, deduït d'altres impresos Text a 1 col Sign.: [ ]2
Inversion oportuna é inesperada que Don Guillermo Atanasio Xaramillo, ha hecho de cien reales vellon que le remitió Don Bartolomé Josef Gallardo : =S…
Text a 1 col Sign.: [ ]2
Impugnacion del Diccionario burlesco, que contra las leyes divinas y humanas publicara un libertino, contra el reglamento de la libertad de imprenta …
Ornamentació tip Text a 1 col Sign.: [ ]4
Geometric inequivalence of metric and Palatini formulations of General Relativity
2020
Projective invariance is a symmetry of the Palatini version of General Relativity which is not present in the metric formulation. The fact that the Riemann tensor changes nontrivially under projective transformations implies that, unlike in the usual metric approach, in the Palatini formulation this tensor is subject to a gauge freedom, which allows some ambiguities even in its scalar contractions. In this sense, we show that for the Schwarzschild solution there exists a projective gauge in which the (affine) Kretschmann scalar, K≡R R , can be set to vanish everywhere. This puts forward that the divergence of curvature scalars may, in some cases, be avoided by a gauge transformation of the …
Crustal controls on light noble gas isotope variability along the andean volcanic arc
2021
This study combines new noble gas data from fluid inclusions in minerals from Sabancaya, Ubinas, and El Misti (CVZ, Peru) and Villarica (South Chile, SVZ) with a revised noble gas compilation in the Andes, to identify systematic along arc variations in helium isotope compositions. We find 3He/4He ratios varying from 8.8 RA (Colombia) to 7.4 RA (Ecuador) within the NVZ, and only as high as 6.4 RA in the CVZ (RA is the atmospheric 3He/4He ratio of 1.39 × 10–6). These distinct isotope compositions cannot be explained by variable radiogenic 4He production via slab fluid transport of U and Th in the mantle wedge, since both NVZ and CVZ share similar slab sediment inputs (Th/La ≈ 0.08–0.13). Inst…
Nutritional status, physical performance and disability in the elderly of the Peruvian Andes
2016
Background: Although nutritional status plays an important part in the physical performance and disability of older people, this relationship has been little studied in developing countries. Aims: A study on the effects of nutritional status on the physical performance and functional status of elderly people living in rural areas of the Peruvian Andes. Methods: The study concerned 222 people aged ≥65 years living in a rural area of the Peruvian Andes. The Mini-Nutritional Assessment (MNA) was used to classify participants as malnourished (MNA <= 17), at risk of malnutrition (MNA 18-23), or well-nourished (MNA>= 24). The short physical performance battery (SPPB) and six-minute walking …
Psychosocial risks at work and occupational health
2012
Los cambios que han ocurrido en las últimas décadas sobre los procesos laborales y el diseño del trabajo son de carácter sociodemográfico, económico, político, y tecnológico. Estos cambios han originado nuevos riesgos psicosociales en el trabajo que afectan a la salud y la calidad de vida laboral, pues incrementan los niveles de estrés de los trabajadores. El objetivo del estudio es presentar este tipo de riesgos, sus consecuencias, y algunas recomendaciones para promover la salud en el trabajo como estrategia para mejorar la salud pública de la población. El estudio se estructura en cinco puntos en los que: (1) se presenta el concepto de factores y riesgos psicosociales en el trabajo, (2) …
Active Site Mapping of Xylan-Deconstructing Enzymes with Arabinoxylan Oligosaccharides Produced by Automated Glycan Assembly
2017
Xylan-degrading enzymes are crucial for the deconstruction of hemicellulosic biomass, making the hydrolysis products available for various industrial applications such as the production of biofuel. To determine the substrate specificities of these enzymes, we prepared a collection of complex xylan oligosaccharides by automated glycan assembly. Seven differentially protected building blocks provided the basis for the modular assembly of 2-substituted, 3-substituted, and 2-/3-substituted arabino- and glucuronoxylan oligosaccharides. Elongation of the xylan backbone relied on iterative additions of C4-fluorenylmethoxylcarbonyl (Fmoc) protected xylose building blocks to a linker-functionalized …
Aspirações vitais e sua relação com a paixão, em atletas argentinos selecionados para os Jogos Olímpicos da Juventude
2018
El objetivo de este trabajo fue estudiar las aspiraciones vitales de deportistas adolescentes de alto rendimiento y su relación con la pasión que tienen con respecto a su deporte. Participaron 234 deportistas argentinos (47,9 % varones; 52,1 % mujeres) de entre 12 y 16 años de edad (M = 14,48; DT = 1,09) pertenecientes al Plan de Desarrollo de los Juegos Olímpicos de la Juventud (Buenos Aires, 2018), quienes respondieron un cuestionario sociodemográfico, el Inventario de Aspiraciones vitales y la Escala de Pasión. Los varones obtuvieron puntajes significativamente más altos que las mujeres en las aspiraciones de riqueza y fama, así como también en pasión obsesiva. Para los varones, el creci…