4,034 research outputs found
Una nueva especie del gĂ©nero Yuriria Jordan & Evermann, 1896 (Actinopterygii, Cyprinidae) de la cuenca del rĂo Ameca en la Mesa Central Mexicana
A new cyprinid species is described based on morfometric, meristic and genetic characters. The new species identified, Yuriria amatlana sp. nov., inhabits the high Ameca Basin in the central plateau of Mexico. This Mexican minnow differs from Yuriria alta and Yuriria chapalae in terms of the following characters: (50-52) 53-54 pored lateralline scales; 10 upper transverse-line scales, 5-6 lower transverse-line scales and 8-10 gill rakers. Body coloration is light yellowish-brown. Compared to Yuriria alta and Yuriria chapalae, the new species has a less conspicuous dark grey band running from the start of the dorsal fin to the head. Cytochrome b gene sequences differ from those of Yuriria alta and Yuriria chapalae in terms of 29 fixed nucleotide positions (molecular autopomorphies). Calculated genetic divergences for the cytochrome b gene were: `DHKY = 3.8 (3.2-4.4%) between Yuriria amatlana sp. nov. and Y. alta; `DHKY = 5 (4.8-5.2%) between Y. amatlana sp. nov and Y. chapalae; and `DHKY = 2.6 (2.1-3.3%) between Y. chapalae and Y. alta.Se describe una nueva especie, Yuriria amatlana sp. nov., en base a caracteres morfomĂ©tricos, merĂsticos y genĂ©ticos. La nueva especie proviene de la parte alta de la cuenca del rĂo Ameca en la Meseta Central de MĂ©xico. Esta especie se diferencia de Yuriria alta y Yuriria chapalae por una combinaciĂłn de los siguientes caracteres: (50-52) 53-54 escamas en una serie longitudinal, 10 escamas en una serie transversal por encima de la lĂnea lateral y 5-6 escamas por debajo de la lĂnea lateral y 8-10 branquiespinas. El color del cuerpo es amarillo-marrĂłn claro. La nueva especie tiene una banda gris oscura menos marcada en el cuerpo desde el comienzo de la aleta dorsal hacia la cabeza con respecto a Yuriria alta y Yuriria chapalae. La nueva especie se diferencia de Yuriria alta y Yuriria chapalae en 29 posiciones nucleotĂdicas fijadas (autopomorfias moleculares) para el citocromo b. La divergencia genĂ©tica entre Yuriria alta y Yuriria amatlana sp. nov. para el citocromo b fue de `DHKY = 3.8 (3.2-4.4%); entre Y. amatlana sp. nov. y Y. chapalae fue `DHKY = 5 (4.8-5.2%) y entre Y. chapalae y Y. alta fue `DHKY = 2.6 (2.1-3.3%)
Transformation Optics Approach to Plasmon-Exciton Strong Coupling in Nanocavities
We investigate the conditions yielding plasmon-exciton strong coupling at the
single emitter level in the gap between two metal nanoparticles. A
quasi-analytical transformation optics approach is developed that makes
possible a thorough exploration of this hybrid system incorporating the full
richness of its plasmonic spectrum. This allows us to reveal that by placing
the emitter away from the cavity center, its coupling to multipolar dark modes
of both even and odd parity increases remarkably. This way, reversible dynamics
in the population of the quantum emitter takes place in feasible
implementations of this archetypal nanocavity.Comment: 5 pages, 4 figure
Effective capillary interaction of spherical particles at fluid interfaces
We present a detailed analysis of the effective force between two smooth
spherical colloids floating at a fluid interface due to deformations of the
interface. The results hold in general and are applicable independently of the
source of the deformation provided the capillary deformations are small so that
a superposition approximation for the deformations is valid. We conclude that
an effective long--ranged attraction is possible if the net force on the system
does not vanish. Otherwise, the interaction is short--ranged and cannot be
computed reliably based on the superposition approximation. As an application,
we consider the case of like--charged, smooth nanoparticles and
electrostatically induced capillary deformation. The resulting long--ranged
capillary attraction can be easily tuned by a relatively small external
electrostatic field, but it cannot explain recent experimental observations of
attraction if these experimental systems were indeed isolated.Comment: 23 page
High-order localized spoof surface plasmon resonances and experimental verifications
We theoretically demonstrated and experimentally verified high-order radial
spoof localized surface plasmon resonances supported by textured metal
particles. Through an effective medium theory and exact numerical simulations,
we show the emergence of these geometrically-originated electromagnetic modes
at microwave frequencies. The occurrence of high-order radial spoof plasmon
resonances is experimentally verified in ultrathin disks. Their spectral and
near-field properties are characterized experimentally, showing an excellent
agreement with theoretical predictions. Our findings shed light into the nature
of spoof localized surface plasmons, and open the way to the design of
broadband plasmonic devices able to operate at very different frequency
regimes.Comment: 29 pages, 10 figure
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