163 research outputs found
Tailor-made directional emission in nanoimprinted plasmonic-based light-emitting devices
We demonstrate an enhanced and tailor-made directional emission of light-emitting devices using nanoimprinted hexagonal arrays of aluminum nanoparticles. Fourier microscopy reveals that the luminescence of the device is not only determined by the material properties of the organic dye molecules but is also strongly influenced by the coherent scattering resulting from periodically arranged metal nanoparticles. Emitters can couple to lattice-induced hybrid plasmonic–photonic modes sustained by plasmonic arrays. Such modes enhance the spatial coherence of an emitting layer, allowing the efficient beaming of the emission along narrow angular and spectral ranges. We show that tailoring the separation of the nanoparticles in the array yields an accurate angular distribution of the emission. This combination of large-area metal nanostructures fabricated by nanoimprint lithography and light-emitting devices is beneficial for the design and optimization of solid-state lighting systems
Evolution Operators for Linearly Polarized Two-Killing Cosmological Models
We give a general procedure to obtain non perturbative evolution operators in
closed form for quantized linearly polarized two Killing vector reductions of
general relativity with a cosmological interpretation. We study the
representation of these operators in Fock spaces and discuss in detail the
conditions leading to unitary evolutions.Comment: Accepted for publication in Physical Review
Hamiltonian Dynamics of Linearly Polarized Gowdy Models Coupled to Massless Scalar Fields
The purpose of this paper is to analyze in detail the Hamiltonian formulation
for the compact Gowdy models coupled to massless scalar fields as a necessary
first step towards their quantization. We will pay special attention to the
coupling of matter and those features that arise for the three-handle and
three-sphere topologies that are not present in the well studied three torus
case -in particular the polar constraints that come from the regularity
conditions on the metric. As a byproduct of our analysis we will get an
alternative understanding, within the Hamiltonian framework, of the appearance
of initial and final singularities for these models.Comment: Final version to appear in Classical and Quantum Gravit
Unitary evolution of free massless fields in de Sitter space-time
We consider the quantum dynamics of a massless scalar field in de Sitter
space-time. The classical evolution is represented by a canonical
transformation on the phase space for the field theory. By studying the
corresponding Bogoliubov transformations, we show that the symplectic map that
encodes the evolution between two instants of time cannot be unitarily
implemented on any Fock space built from a SO(4)-symmetric complex structure.
We will show also that, in contrast with some effectively lower dimensional
examples arising from Quantum General Relativity such as Gowdy models, it is
impossible to find a time dependent conformal redefinition of the massless
scalar field leading to a quantum unitary dynamics.Comment: 20 pages. Comments and references adde
Computational thinking through design patterns in video games
Computer Systems, Imagery and Medi
Endoglin-mediated angiogenic responses are regulated by its cytosolic domain
1 p.This work was supported by grants from Czech Science foundation GACR number 15-24015S, the Grant Agency of Charles University in Prague (1284214/C and 1158413/C), Charles University in Prague (SVV/2014/260064), European Regional Development Fund under the Innovative Economy Program of the European Union (grant coordinated by JCET-UJ, No POIG.01.01.02-
00-069/09), Ministerio de Economia y Competitividad of Spain
(SAF2010-19222 and SAF2013-43421-R and SAF2010-1588), Junta de Castilla y Leon (GR100), Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) and Red de Investigación Cooperativa en Enfermedades Renales (RD12/0021/0032; REDINREN).
CIBERER and REDINREN are initiatives of the Instituto de
Salud Carlos III (ISCIII) of Spain supported by FEDER funds. The
Cardiovascular Phenotyping Unit of the University of Salamanca,
including the telemetry equipment, was acquired with the support of the European Regional Development Funds (FEDER). Ministerio de Economia y Competitividad (BES-2008-005550). The publication is co-financed by the European Social Fund and the state budget of the Czech Republic (Project No.CZ.1.07/2.3.00/30.0061).Peer reviewe
Occupational injuries in workers of a Spanish bank
BACKGROUND: In 2017, 69 108 work-related traffic injuries with medical leave were documented, constituting 12% of all occupational injuries (OI) in Spain.
AIMS: The aim of this study was to describe OI within a Spanish bank company during 2017.
METHODS: A cross-sectional analysis was conducted using the company's mandatory OI records, presenting data in both absolute (n) and relative (%) frequencies. The chi-square test was employed for comparisons.
RESULTS: Among the company's 10 399 employees, 176 OI cases were recorded. Most were minor musculoskeletal incidents, with one severe myocardial infarction and one mild anxiety episode. Lower limb injuries were the most prevalent. Injuries of the trunk (P < 0.001), neck (P < 0.05), and upper limbs (P < 0.001) were linked to workplace factors. Approximately 62% of OI occurred outside the workplace and resulted in more extended medical leave (P < 0.01). Traffic-related injuries accounted for 39% of OI cases and caused 49% of days lost due to OI (P < 0.001).Female gender (P < 0.001) and age over 40 years (P < 0.05) were significantly associated with OI.
CONCLUSIONS: In our study, musculoskeletal injuries were the most common, with a single cardiovascular event being the most severe. OI occurring outside the workplace was more frequent and led to longer medical leaves. Notably, traffic-related injuries were especially significant, exceeding official statistics 4-fold
Desarrollo de un servicio experimental de teledetección en los riegos del Porma (León) para el cálculo ajustado de necesidades hídricas y mejora en la gestión del regadío
El proyecto de innovación tecnológica OPTIREG Eficiencia Hídrica, impulsado por el
Grupo Tragsa, tiene entre sus objetivos principales introducir el uso de la teledetección,
como tecnología de apoyo a la gestión hídrica. Para ello se está desarrollando un servicio
web gis experimental que servirá de repositorio único de imágenes y de sus productos
derivados y que facilitará, tanto a los regantes, como a los gestores del riego, el seguimiento
de los cultivos y de sus necesidades hídricas.
Diversos estudios científicos han demostrado la buena relación lineal existente entre el
índice de vegetación normalizado (NDVI), derivado de las imágenes de satélite, y el
coeficiente de cultivo, Kc (Torres, 2010), utilizado en el cálculo de la evapotranspiración y las
necesidades hídricas. Una primera evaluación de los resultados obtenidos en la campaña
2015 para los principales cultivos en regadío en la zona de estudio del Porma (León), indica
que el Kc calculado a partir del NDVI, se ajusta mejor que el de FAO. Por ello, se considera
un sistema muy válido como referencia para ajustar no sólo la cantidad de agua, sino
también para determinar el momento más adecuado de riego, que redundará en una mayor
eficiencia hídrica
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