Polar coherent states in bilayer graphene under a constant uniform magnetic field

Symmetries associated with the Hamiltonian describing bilayer graphene subjected to a constant magnetic field perpendicular to the plane of the bilayer are calculated using polar coordinates. These symmetries are then applied to explain some fundamental properties, such as the spectrum and the integer pseudo-spin character of the eigenfunctions. The probability and current densities of the bilayer Hamiltonian have also been calculated in polar coordinates and shown to be gauge invariant and scalar under generalized rotations. We also define appropriate coherent states of this system as eigenfunctions, with complex eigenvalues, of a suitable chose annihilation operator. In this framework, symmetries are also useful to show the meaning of the complex eigenvalue in terms of expected values. The local current density of these coherent states is shown to exhibit a kind of radial component interference effect, something that has gone unnoticed until now. Some of these results that have just been exposed are graphically illustrated throughout the manuscript

An overview of the lower cretaceous dinosaur tracksites from the mirambel formation in the iberian range (ne spain)

Up to now, the ichnological vertebrate record from the Barremian Mirambel Formation (NE Spain) has remained completely unknown despite the fact that osteological findings have been reported in recent years. Here we provide an overview of 11 new dinosaur tracksites found during a fieldwork campaign in the year 2011. The majority of these tracksites (seven) preserve small- to medium-sized tridactyl tracks here assigned to indeterminate theropods. Only one footprint presents enough characters to classify it as Megalosauripus isp. Ornithopod tracks identified as Caririchnium isp. and Iguanodontipodidae indet. and sauropod tracks are recorded at two tracksites. The footprints are preserved in a variety of paleoenvironmental conditions and thus display different kinds of preservation (true tracks, shallow undertracks, natural casts and undertrack casts). The ichnological record from the Mirambel Formation seems to be theropod dominated. This is a clear discrepancy with the osteological record identified in this formation, which shows a predominance of ornithopod dinosaurs

A ferric guest inside a spin crossover ferrous helicate

A designed dimetallic Fe(II) helicate made with biphenylenebridged bispyrazolylpyridine ligands and exhibiting a process of spin crossover at temperatures above ambient is shown to encapsulate an S = 5/2 tris-oxalato Fe(III) ion. The spin relaxation dynamics of this guest are strongly reduced upon encapsulatio

Effect of ground-cover management on predatory mites (Acari: Phytoseiidae) in a Mediterranean vineyard

Most predatory mites belong to the family Phytoseiidae (Acari). Throughout the world, phytoseiids are involved in the biological control of phytophagous mites in vineyards. Conservative strategies, including cover-vegetation management, are essential to achieve environmentally friendly viticulture. The abundance and diversity of phytoseiid mites in the grapevine canopy and the vegetal ground cover of a Mediterranean vineyard were surveyed by weekly samplings, from early May until the end of September for two years (2016 and 2017). Three types of soil management without herbicide application were analysed and referred to as "Tillage", "Spontaneous Cover", and "Flower-driven Cover" treatments. Six phytoseiid species were collected on the grapevine canopy, with Typhlodromus pyri being the dominant species (99.5 %). Five phytoseiid species were recorded in the ground cover, with Typhlodromus and Neoseiulus as the major genera. The Flower-driven Cover treatment showed the highest abundance of phytoseiids in the grapevine canopy. However, both species richness and abundance of phytoseiid mites on the ground-cover vegetation were highest in the Spontaneous Cover treatment. These observations suggest that improving vegetation cover would promote both the abundance and diversity of phytoseiid mites in vineyards because the greater supply of pollen would enhance their survival. Therefore, the use of cover crops in vineyards represents a means of improving vineyard ecosystems by conservative biological control

Relativistic quantum mechanics of a Dirac oscillator

The Dirac oscillator is an exactly soluble model recently introduced in the context of many particle models in relativistic quantum mechanics. The model has been also considered as an interaction term for modelling quark confinement in quantum chromodynamics. These considerations should be enough for demonstrating that the Dirac oscillator can be an excellent example in relativistic quantum mechanics. In this paper we offer a solution to the problem and discuss some of its properties. We also discuss a physical picture for the Dirac oscillator's non-standard interaction, showing how it arises on describing the behaviour of a neutral particle carrying an anomalous magnetic moment and moving inside an uniformly charged sphere.Comment: 19 pages, 1 figur

Relativistically extended Blanchard recurrence relation for hydrogenic matrix elements

General recurrence relations for arbitrary non-diagonal, radial hydrogenic matrix elements are derived in Dirac relativistic quantum mechanics. Our approach is based on a generalization of the second hypervirial method previously employed in the non-relativistic Schr\"odinger case. A relativistic version of the Pasternack-Sternheimer relation is thence obtained in the diagonal (i.e. total angular momentum and parity the same) case, from such relation an expression for the relativistic virial theorem is deduced. To contribute to the utility of the relations, explicit expressions for the radial matrix elements of functions of the form $r^\lambda$ and $\beta r^\lambda$ ---where $\beta$ is a Dirac matrix--- are presented.Comment: 21 pages, to be published in J. Phys. B: At. Mol. Opt. Phys. in Apri

Parasites of the red fox (Vulpes vulpes Linnaeus, 1758) in Murcia, southeast Spain

© 2007This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/. This document is the Published version of a Published Work that appeared in final form in Revue Médicine Vétérinaire.Fifty five red foxes were captured in Murcia province (Southeast Spain) and necropsied to evaluate parasitic infections. Fifteen helminth species were found, including five cestodes (Mesocestoides lineatus, Mesocestoides litteratus, Joyeuxiella pasqualei, Taenia pisiformis and Dipylidium caninum), nine nematodes (Pterygodermatites affinis, Toxocara canis, Trichuris vulpis, Toxascaris leonina, Oxynema crassispiculum, Eucoleus (Capillaria) aerophilus, Toxocara cati, Uncinaria stenocephala and Angiostrongylus, vasorum), and one acanthocephalan (Macracanthorhynchus catulinus). Coprological method revealed the presence of, Isospora spp. oocysts. Also, fleas and ticks were recovered from the carcasses, corresponding to Pulex irritans, Spilopsyllus cuniculi, Ctenocephalides felis felis, Rhipicephalus sanguineus, Ixodes ventalloi, and Ixodes ricinus. Both S. cuniculi and C. felis felis are first records in foxes in the Iberian PeninsulaNous avons réalisé une étude parasitologique chez le renard roux (Vulpes vulpes) dans la province de Murcie (sud-est de l’Espagne). Au total, 55 renards ont été collectés et autopsiés. L’examen coprologique parasitaire a révélé la présence d’oocystes d’Isospora spp. Nous avons trouvé quinze espèces de helminthes, desquels cinq sont cestodes (Mesocestoides lineatus, Mesocestoides litteratus, Joyeuxiella pasqualei, Taenia pisiformis et Dipylidium caninum) et neuf nématodes (Pterygodermatites affinis, Toxocara canis, Trichuris vulpis, Toxascaris leonina, Oxynema crassispiculum, Eucoleus (Capillaria) aerophilus, Toxocara cati, Uncinaria stenocephala et Angiostrongylus vasorum), et une espèce d’acanthocephalan (Macracanthorhynchus catulinus). Par ailleurs, nous avons identifié des puces et des tiques appartenant aux espèces Pulex irritans, Spilopsyllus cuniculi, Ctenocephalides felis felis, Rhipicephalus sanguineus, Ixodes ventalloi et Ixodes ricinus. C’est la première fois que S. cuniculi et C. felis felis ont été décrits chez le renard dans la Péninsule Ibérique

Attomolar detection of hepatitis C virus core protein powered by molecular antenna-like effect in a graphene field-effect aptasensor

Biosensors based on graphene field-effect transistors have become a promising tool for detecting a broad range of analytes. However, their performance is substantially affected by the functionalization protocol. In this work, we use a controlled in-vacuum physical method for the covalent functionalization of graphene to construct ultrasensitive aptamer-based biosensors (aptasensors) able to detect hepatitis C virus core protein. These devices are highly specific and robust, achieving attomolar detection of the viral protein in human blood plasma. Such an improved sensitivity is rationalized by theoretical calculations showing that induced polarization at the graphene interface, caused by the proximity of covalently bound molecular probe, modulates the charge balance at the graphene/aptamer interface. This charge balance causes a net shift of the Dirac cone providing enhanced sensitivity for the attomolar detection of the target proteins. Such an unexpected effect paves the way for using this kind of graphene-based functionalized platforms for ultrasensitive and real-time diagnostics of different diseases.EU Graphene Flagship funding (Grant Graphene Core3 881603), the Ministerio de Ciencia e Innovación of Spain: PID2020-113142RB-C21, the European Structural Funds via FotoArt-CM project (P2018/NMT-4367) and the Portuguese Foundation for Science and Technology (FCT) via the Strategic Funding UIDB/04650/2020. Work at CAB was funded by the Spanish Ministerio de Ciencia e Innovación (MICINN) grant no. PID2019-104903RB-I00 and the Spanish Agencia Estatal de Investigación (AEI) Project no. MDM-2017-0737 - Unidad de Excelencia “María de Maeztu,” and it also benefits from the interdisciplinary framework provided by CSIC through “LifeHUB.CSIC” initiative (PIE 202120E047-CONEXIONES-LIFE). CIBERehd is funded by Instituto de Salud Carlos III (ISCIII). A.N. is supported by the predoctoral fellowship PRE-CAB-BIOMOLECULAS 2 from INTA. B.T-V. is supported by the predoctoral fellowship TS17/16 from INTA and by the CSIC “Garantía Juvenil” contract CAM19_PRE_CAB_001 funded by Comunidad de Madrid (CAM). FCT supports T.D. and P.C. under Ph.D. grants SFRH/BD/08181/2020 and SFRH/BD/128579/2017. M.M. would like to thank Comunidad de Madrid for the predoctoral grant IND2020/BIO-17523. P.A. and C.B. also acknowledge the support provided by La Caixa Foundation through Project LCF/PR/HR21/52410023. L. V. would like to thank Comunidad de Madrid (TRANSNANOAVANSENS program: S2018-NMT-4349) and E.V. García-Frutos for her assistance during the AFM experiments

Using radio astronomical receivers for molecular spectroscopic characterization in astrochemical laboratory simulations: A proof of concept

We present a proof of concept on the coupling of radio astronomical receivers and spectrometers with chemical reactorsand the performances of the resulting setup for spectroscopy and chemical simulations in laboratory astrophysics. Several experiments including cold plasma generation and UV photochemistry were performed in a 40\,cm long gas cell placed in the beam path of the Aries 40\,m radio telescope receivers operating in the 41-49 GHz frequency range interfaced with fast Fourier transform spectrometers providing 2 GHz bandwidth and 38 kHz resolution. The impedance matching of the cell windows has been studied using different materials. The choice of the material and its thickness was critical to obtain a sensitivity identical to that of standard radio astronomical observations. Spectroscopic signals arising from very low partial pressures of CH3OH, CH3CH2OH, HCOOH, OCS,CS, SO2 (<1E-03 mbar) were detected in a few seconds. Fast data acquisition was achieved allowing for kinetic measurements in fragmentation experiments using electron impact or UV irradiation. Time evolution of chemical reactions involving OCS, O2 and CS2 was also observed demonstrating that reactive species, such as CS, can be maintained with high abundance in the gas phase during these experiments.Comment: Accepted for publication in Astronomy and Astrophysics in September 21, 2017. 16 pages, 18 figure

Frecuencia de riego en variedades tintas: Repercusión en la producción y la composición de la uva, durante un periodo bienal, en 4 regiones de España

Resumen La restricción hídrica es un aspecto limitante del cultivo del viñedo en muchas regiones, por lo que el riego constituye uno de los principales factores determinantes de su desarrollo en muchas zonas, que ha sido estudiado en diferentes ámbitos, pero la frecuencia de aplicación del riego, que afecta a su distribución en el suelo y puede influir en el comportamiento del viñedo, no ha sido suficientemente evaluada, por lo que su estudio resulta de gran interés en diversas condiciones de cultivo. El objetivo de este trabajo fue evaluar los efectos de cuatro frecuencias de riego deficitario del 30% ET0: 7 riegos por semana (T01), 2 riegos por semana (T03), 1 riego por semana (T07) y 1 riego cada dos semanas (T15), en la producción de uva y la composición de la baya. El experimento se desarrolló durante los años 2021 y 2022, en viñedos de Garnacha Tinta (en Badajoz: T03, T07, T15), Tempranillo (en Valladolid: T03, T07, T15), Syrah (en Albacete: T03 y T07) y Mencía (en Lugo: T01, T03, T07). Tanto la producción como la composición de la uva fueron determinadas en vendimia. Las diferentes frecuencias de riego han repercutido en el rendimiento y la calidad de la uva de forma variable según la variedad, la localización y el año. La producción de uva y la madera de poda se vieron ligeramente favorecidos por la frecuencia T07 con respecto a T03 en Garnacha y, sólo en la producción, en Tempranillo, mientras que ocurrió lo contrario en Syrah y Mencía. La concentración de azúcares se vio ligeramente favorecida por la frecuencia T07 en Syrah y, parcialmente, en Tempranillo. El pH del mosto no ofreció una respuesta apreciable derivada de la frecuencia de riego. La acidez total mostró valores ligeramente superiores de T07 en Garnacha y Tempranillo, pero algo más altos de T03 en Syrah y Mencía. El ácido tartárico apenas presentó una ligera tendencia favorable a T07 en Garnacha, mientras que el ácido málico mostró una tendencia ligeramente favorable a T07 en Garnacha y Mencía, pero beneficiosa para T03 en Syrah. El contenido de potasio y de polifenoles totales ofreció una clara variabilidad entre frecuencias de riego en general, aunque el primero mostró un ligero aumento del T03 con respecto al T07 en Mencía y el segundo un ligero aumento del T07 frente al T03 en Syrah. En definitiva, los efectos productivos y cualitativos derivados de la frecuencia de riego aplicada han tenido un alcance reducido, que, sin embargo, puede variar moderadamente en función de la variedad y del año