RESUMEN

Since mid-2015, there has been an increasing number of chicken samples that are positive for infectious bronchitis virus (IBV) in a screening PCR but which do not show positive results in any established, variant-specific PCR tests (793B, QX, D1466, Massachusetts, D274, Italy 02, Arkansas, Variant 2, Q1). Partial sequencing of the viral genome of those samples shows great similarities, but nucleotide similarity in the S1 gene is only about 57%-61% when compared to any other known GI-GVII IBV genotype and lineage. With nucleotide identity in the S1 gene of approximately 80%, the closest related strain in the National Center for Biotechnology Information database (as of March 15, 2020) is the North American PA/1220/98 isolate (AY789942) designated as a unique variant by Valastro et al. in 2016. Due to its divergence from other IBV strains, we propose that strain, designated IB80, is the type strain of a novel IBV genotype GVIII. So far, IB80 has been detected in commercial layer and broiler parent flocks, frequently showing severe drops in egg production as well as in broiler flocks in Europe and beyond.

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IB80­un nuevo genotipo del virus de la bronquitis infecciosa (GVIII). Desde mediados del 2015, ha habido un número creciente de muestras de pollo que resultan positivas para el virus de la bronquitis infecciosa (IBV) por la detección mediante PCR de escrutinio, pero que no muestran resultados positivos en ninguna prueba de PCR específica para las variantes establecidas (793B, QX, D1466, Massachusetts, D274, Italia 02, Arkansas, variante 2, Q1). La secuenciación parcial del genoma viral de esas muestras muestra grandes similitudes, pero la similitud de nucleótidos en el gene S1 es solo del 57% al 61% en comparación con cualquier otro genotipo y linaje GI-GVII conocidos del virus de bronquitis. Con una identidad de nucleótidos en el gene S1 de aproximadamente el 80 %, la cepa relacionada más cercana en la base de datos del Centro Nacional de Información Biotecnológica (al 15 de marzo de 2020) es el aislamiento norteamericano PA/1220/98 (AY789942) designado como variante única por Valastro et al. en 2016. Debido a su divergencia con otras cepas del virus de bronquitis infecciosa, se propone que la cepa, denominada IB80, es la cepa tipo de un nuevo genotipo GVIII del virus de bronquitis infecciosa. Hasta ahora, se ha detectado IB80 en parvadas de reproductoras de pollos de engorde y ponedoras comerciales, y con frecuencia muestra disminuciones severas en la producción de huevo, así como en parvadas de pollos de engorde en Europa y otras regiones.

Asunto(s)

Infecciones por Coronavirus , Virus de la Bronquitis Infecciosa , Enfermedades de las Aves de Corral , Animales , Pollos , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/veterinaria , Genotipo , Virus de la Bronquitis Infecciosa/genética , Nucleótidos , Filogenia , Enfermedades de las Aves de Corral/epidemiología

RESUMEN

The Keffi area hosts abundant pegmatite bodies as a result of the surrounding granitic intrusions. Keffi is part of areas that are geologically classified as North Central Basement Complex. Data on the mineralogy and mineralogical zonation of the Keffi pegmatite are scanty. Hence the need to understand the geology and mineralogical zonation of Keffi pegmatites especially at different depth profiles is relevant as a study of the elemental composition of the pegmatite is essential for the estimation of its economic viability. Here, the relative standardization method of instrumental neutron activation analysis (INAA) has been used to investigate the vertical deviations of the elemental concentrations of rare earth elements (REEs) at different depth profile of Keffi pegmatite. This study adopted the following metrics in investigating the vertical variations of REEs concentrations. Namely, the total contents of rare earth elements (∑REE); ratio of light to heavy rare earth elements (LREE/HREE), which defines the enrichment or depletion of REEs; europium anomaly (Eu/Sm); La/Lu ratio relative to chondritic meteorites. The study showed no significant variations in the total content of rare elements between the vertical depth profiles (100-250m). However, higher total concentrations of REEs (~ 92.65ppm) were recorded at the upper depth of the pegmatite and the europium anomaly was consistently negative at all the depth profiles suggesting that the Keffi pegmatite is enriched with light REEs.

RESUMEN

Quantum entanglement lies at the heart of quantum information and quantum metrology. In quantum metrology, with a colossal amount of quantum Fisher information (QFI), entangled systems can be ameliorated to be a better resource scheme. However, noisy channels affect the QFI substantially. This research work seeks to investigate how QFI of N-qubit Greenberger-Horne-Zeilinger (GHZ) state is affected when subjected to decoherence channels: bit-phase flip (BPF) and generalize amplitude damping (GAD) channels, which can be induced experimentally. We determine the evolution under these channels, deduce the eigenvalues, and then derive the QFI. We found that when there is no interaction with the environment, the Heisenberg limit can be achieved via rotations along the z direction. It has been shown that in BPF channel, the maximal mean QFI of the N-qubit GHZ state ([Formula: see text]) dwindles as decoherence rate (p B ) increases due to flow of information from the system to the environment, until p B = 0.5, then revives to form a symmetric around p B = 0.5. Thus, p B > 0.5 leads to a situation where more noise yields more efficiency. We found that in GAD channel, at finite temperature, QFIs decay more rapidly than at zero temperature. Our results also reveal that QFI can be enhanced by adjusting the temperature of the environment.

RESUMEN

Thermodynamic quantities of a two-dimensional Yukawa system, a model for various systems including single-layered dust particles observed in dusty plasmas, are obtained and expressed by simple interpolation formulas. In the domain of weak coupling, the analytical method based on the cluster expansion is applied and, in the domain of intermediate and strong coupling, numerical simulations are performed. Due to reduced dimensionality, the treatment based on the mean field fails at the short range and exact behavior of the binary correlation is to be taken into account even in the case of weak coupling.

RESUMEN

Single-layered two-dimensional crystals of dust particles are often observed in dusty plasma experiments and the data on their structure can be obtained by analyzing the images usually taken by charge-coupled [corrected] device cameras. We give here some formulas for practical purposes of estimating the screening length and the electric charge on a dust particle from the surface density and the radius of such finite two-dimensional dust crystals. The formulas are derived on the basis of our theoretical approach which has been successful in reproducing results of molecular-dynamics simulations on dusty plasmas. An example of application is also shown.