Optical spectroscopy of rare-earth ions doped KY(WO4)2 thin films

KY(WO4)2 thin films doped with Dy3+, Tb3+, Yb3+, were grown onto KY(WO4)2 substrates using liquid-phase epitaxy. Spectroscopic investigations of the grown layers were performed. Obtained results were compared with spectra given for bulk crystals. Upconversion experiments after direct Yb3+ excitation in Dy3+-Yb3+ and Tb3+-Yb3+ codoped layers will be also presented

Optical spectroscopic study of Al₂O₃:Ti³⁺ under hydrostatic pressure

This work investigates the effect of hydrostatic pressure on the excitation, emission and lifetime of Ti3+-doped Al2O3 in the 0–110 kbar range. The application of pressure induces band shifts that are correlated with the corresponding local structural changes undergone by the TiO6 complex. The increase of the Stokes-shift and the reduction of the Jahn–Teller (JT) splittings under pressure are analysed in terms of a simple model based on linear electron–phonon couplings to the a1g and the JT eg vibrational modes

Low-temperature flux growth of sulfates, molybdates, and tungstates of Ca, Sr, and Ba and investigation of doping with Mn 6 +

The growth of undoped and Mn6+-doped molybdates and tungstates of alkali-earth metals and BaSO4 has been investigated. Single crystals were grown by the flux method within the temperature range of 600-475°C, using the ternary NaCl-KCl-CsCl solvent. Sizes of undoped crystals increase within the series tungstates<molybdates<sulfate and, depending on the cation, within the series Ca2+≈Sr2+<Ba2+. The Mn6+ ion tends to be reduced to Mn5+/Mn4+ with time in the chloride solution, but can be partly stabilized by the addition of alkali-metal carbonates or hydroxides. The incorporation of Mn6+ is governed by the coordination of the MnO4 2- tetrahedron in the crystal. No significant doping was found for Ca and Sr compounds and only small amounts of Mn6+ were incorporated into BaMoO4 and BaWO4. Crystals with orthorhombic space group Pnma such as BaSO4 exhibit significantly higher doping levels. The Mn6+ distribution in each crystal varies due to manganese reduction with growth time. Temperature-, time-, and concentration-dependent spectroscopy of BaSO4:Mn6+ was performe

Audiometría con extensión en altas frecuencias (9.000-20.000 Hz): Utilidad en el diagnóstico audiológico

This is the peer reviewed version of the following article: Acta Otorrinolaringológica 67.1 (2016): 40-44, which has been published in final form at http://dx.doi.org/10.1016/j.otorri.2015.02.002Early detection and appropriate treatment of hearing loss are essential to minimise the consequences of hearing loss. In addition to conventional audiometry (125-8,000 Hz), extended high-frequency audiometry (9,000-20,000 Hz) is available. This type of audiometry may be useful in early diagnosis of hearing loss in certain conditions, such as the ototoxic effect of cisplatin-based treatment, noise exposure or oral misunderstanding, especially in noisy environments. Eleven examples are shown in which extended high-frequency audiometry has been useful in early detection of hearing loss, despite the subject having a normal conventional audiometry. The goal of the present paper was to highlight the importance of the extended high-frequency audiometry examination for it to become a standard tool in routine audiological examinations.La detección precoz y el tratamiento adecuado de la hipoacusia es fundamental para minimizar las consecuencias de la pérdida auditiva. Además de la audiometría convencional (125-8.000 Hz), disponemos de la audiometría con extensión en altas frecuencias (9.000-20.000 Hz), que puede ser de gran utilidad en el diagnóstico precoz de hipoacusia en ciertas patologías, como es el efecto ototóxico de los tratamientos quimioterápicos, la exposición a ruido o el mal entendimiento del lenguaje, especialmente en ambientes ruidosos. Aquí se presentan 11 casos clínicos en los que la audiometría con extensión en altas frecuencias ha ayudado en la detección precoz de la hipoacusia en diversas patologías, a pesar de tener una audiometría normal en frecuencias convencionales. Se pretende así destacar la importancia de la exploración audiométrica en altas frecuencias, con el fin de que se convierta en una herramienta habitual en la exploración audiológic

Respuesta reproductiva de conejas alimentadas con dietas enriquecidas con aceite de salmón

Un total de 136 conejas luníparasse alimentaron ad libitum desde las 10 semanas de edad con dos piensos isofibrosos, isoenergéticos e isoproteicos formulados con dos fuentes de grasa diferentes: manteca (grupo C; n=68) y un suplemento a base de aceite de salmón rico en ácidos grasos poliinsaturados (PUFA) n=3 (grupo P, n=68) con un nivel de inclusión de 1,5% (7,5g/kg) hasta el primer parto y de 3% (15g/kg) hasta el 2º destete. El peso y la composición corporal de las conejas a lo largo del estudio fueron similares entre grupos a pesar de que las conejas del grupo P redujeron el consumo al incrementar el nivel de inclusión de PUFA n-3. La prolificidad, el peso de los gazapos al nacimiento y el número de destetados fue similar en los dos grupos pero en los gazapos del grupo C la ganancia media diaria tendió a ser mayo, así como su peso al destete. No obstante, la fertilidad media fue más de un 12% superior en las conejas del grupo P, por lo que, el número estimado de gazapos destetados por coneja y año resultó mayor en ellas. En conclusión, el incremento en los niveles de inclusión de ácidos grasos poliisaturados n-3 de 7,5 a 15 g/kg después del primer parto disminuyó el consumo de las madres reduciendo el crecimiento de sus camadas pero incidiendo positivamente sobre su fertilidad

On the construction of a geometric invariant measuring the deviation from Kerr data

This article contains a detailed and rigorous proof of the construction of a geometric invariant for initial data sets for the Einstein vacuum field equations. This geometric invariant vanishes if and only if the initial data set corresponds to data for the Kerr spacetime, and thus, it characterises this type of data. The construction presented is valid for boosted and non-boosted initial data sets which are, in a sense, asymptotically Schwarzschildean. As a preliminary step to the construction of the geometric invariant, an analysis of a characterisation of the Kerr spacetime in terms of Killing spinors is carried out. A space spinor split of the (spacetime) Killing spinor equation is performed, to obtain a set of three conditions ensuring the existence of a Killing spinor of the development of the initial data set. In order to construct the geometric invariant, we introduce the notion of approximate Killing spinors. These spinors are symmetric valence 2 spinors intrinsic to the initial hypersurface and satisfy a certain second order elliptic equation ---the approximate Killing spinor equation. This equation arises as the Euler-Lagrange equation of a non-negative integral functional. This functional constitutes part of our geometric invariant ---however, the whole functional does not come from a variational principle. The asymptotic behaviour of solutions to the approximate Killing spinor equation is studied and an existence theorem is presented.Comment: 36 pages. Updated references. Technical details correcte

Asymptotic expansions of the Cotton-York tensor on slices of stationary spacetimes

We discuss expansions for the Cotton-York tensor near infinity for arbitrary slices of stationary spacetimes. From these expansions it follows directly that a necessary condition for the existence of conformally flat slices in stationary solutions is the vanishing of a certain quantity of quadrupolar nature (obstruction). The obstruction is nonzero for the Kerr solution. Thus, the Kerr metric admits no conformally flat slices. An analysis of higher orders in the expansions of the Cotton-York tensor for solutions such that the obstruction vanishes suggests that the only stationary solution admitting conformally flat slices are the Schwarzschild family of solutions.Comment: Revised version to appear in Class. Quantum Grav. with 13 pages. Section 2 regarding multipolar expansions of stationary spacetimes largely expanded. A Maple script demonstrating the calculations in the axially symmetric case is available upon request from the autho

Eosinophilic esophagitis: A relevant entity for the otolaryngologist

This is the peer reviewed version of the following article: Acta Otorrinolaringológica 67.3 (2016): 167-168, which has been published in final form at http://dx.doi.org/10.1016/j.otorri.2015.06.002Eosinophilic esophagitis (EE) is a recently recognised pathologic entity whose prevalence has risen significantly since it was first described. Its diagnosis represents a challenge for different medical specialties, among which ENT specialists play an important role. Clinical suspicion in a patient with recurrent food impaction or a child with eating disorders and history of hypersensitivity constitutes the first warning sign of a possible EE.The purpose of this review is to highlight EE as a possible differential diagnosis in patients with deglutition disorders and describe the possible clinical symptoms that should alert the ENT specialist to perform appropriate diagnostic tests and procedures. The transnasal esophagoscopy, performed in-office by the ENT, is ideal for reducing possible underdiagnosed cases.Given the fact that an ENT specialist will evaluate a great many patients with deglutition disorders, it is paramount for possible EE cases to be suspected and recognised so that a correct multidisciplinary approach involving not only ENT specialists but also paediatricians, gastroenterologists, allergologists and pathologists can be established. Identifying the dietary component responsible for the esophageal inflammation and removing that food from the patient's diet is the key in the treatment of this immune-mediated disease.La esofagitis eosinofílica (EE) es una entidad clínico patológica reconocida recientemente y con una prevalencia que va en aumento desde su descripción inicial. Su diagnóstico representa un reto para diferentes especialistas, entre los que tiene un rol destacado el otorrinolaringólogo. La sospecha clínica ante un paciente que presenta episodios recidivantes de impactación de alimentos no punzantes o ante un niño con trastornos de la alimentación y antecedentes de atopia constituyen el primer signo de alerta de una posible EE. El objetivo de esta revisión persigue destacar el papel de la EE en el diagnóstico diferencial de los pacientes con trastornos de la deglución, así como dar a conocer las manifestaciones clínicas que deben alertar al otorrinolaringólogo para proseguir la realización de las pruebas encaminadas al diagnóstico de esta enfermedad. La esofagoscopia transnasal, realizada por el otorrinolaringólogo en consulta, ayudará a disminuir el número de casos infradiagnosticados. Dado que gran parte de los pacientes afectos de trastornos de la deglución van a ser evaluados por el otorrinolaringólogo, se hace imprescindible el reconocimiento de la EE, así como el manejo diagnóstico-terapéutico por un equipo multidisciplinar en el que se involucren, además del otorrinolaringólogo, pediatras, digestólogos, alergólogos y patólogos familiarizados con la enfermedad. La identificación del alimento responsable de la inflamación del esófago y su eliminación de la dieta es la clave del tratamiento de este desorden inmunomediad

In vitro and in vivo effects of lutein against cisplatin-induced ototoxicity

This is peer reviewed version of the following article Experimental and Toxicologic Pathology 68.4 (2016): 197-204, which has been published in final form at http://dx.doi.org/10.1016/j.etp.2016.01.003Introduction: Cisplatin is a commonly prescribed drug that produces ototoxicity as a side effect. Lutein is a carotenoid with antioxidant and anti-inflammatory properties previously tested for eye, heart and skin diseases but not evaluated to date in ear diseases. Aim: To evaluate the protective effects of lutein on HEI-OC1 auditory cell line and in a Wistar rat model of cisplatin ototoxicity. Materials and Methods: In vitro study: Culture HEI-OC1 cells were exposed to lutein (2.5-100 μM) and to 25 μM cisplatin for 24 h. In vivo study: Twenty eight female Wistar rats were randomized into three groups. Group A (n = 8) received intratympanic lutein (0.03 mL) (1 mg/mL) in the right ear and saline solution in the left one to determine the toxicity of lutein. Group B (n = 8) received also intraperitoneal cisplatin (10 mg/kg) to test the efficacy of lutein against cisplatin ototoxicity. Group C (n = 12) received intratympanic lutein (0.03 mL) (1 mg/mL) to quantify lutein in cochlear fluids (30 min, 1 h and 5 days after treatment). Hearing function was evaluated by means of Auditory Steady-State Responses before the procedure and 5 days after (groups A and B). Morphological changes were studied by confocal laser scanning microscopy. Results: In vitro study: Lutein significantly reduced the cisplatin-induced cytotoxicity in the HEI-OC1 cells when they were pre-treated with lutein concentrations of 60 and 80 μM. In vivo study: Intratympanic lutein (1 mg/mL) application showed no ototoxic effects. However it did not achieve protective effect against cisplatin-induced ototoxicity in Wistar rats. Conclusions: Although lutein has shown beneficial effects in other pathologies, the present study only obtained protection against cisplatin ototoxicity in culture cells, but not in the in vivo model. The large molecule size, the low dose administered, and restriction to diffusion in the inner ear could account for this negative result.Research supported by a Spanish FIS Grant EI 11/00742