Sound focusing by gradient index sonic lenses

Gradient index sonic lenses based on two-dimensional sonic crystals are here designed, fabricated and characterized. The index-gradient is achieved in these type of flat lenses by a gradual modification of the sonic crystal filling fraction along the direction perpendicular to the lens axis. The focusing performance is well described by an analytical model based on ray theory as well as by numerical simulations based on the multiple-scattering theory.Comment: 4 pages, 4 figure

Extended Far-Infrared CO Emission in the Orion OMC-1 Core

We report on sensitive far-infrared observations of $^{12}$CO pure rotational transitions in the OMC-1 core of Orion. The lines were observed with the Long Wavelength Spectrometer (LWS) in the grating mode on board the Infrared Space Observatory (ISO), covering the 43-197 $\mu$m wavelength range. The transitions from $J_{up}=14$ up to $J_{up}=19$ have been identified across the whole OMC-1 core and lines up to $J_{up}= 43$ have been detected towards the central region, KL/IRc2. In addition, we have taken high-quality spectra in the Fabry-Perot mode of some of the CO lines. In KL/IRc2 the lines are satisfactorily accounted for by a three-temperature model describing the plateau and ridge emission. The fluxes detected in the high-$J$ transitions ($J_{up} > 34$) reveal the presence of a very hot and dense gas component ($T=1500-2500$ K; $\rm N(CO)$=2\times 10^{17}\cmmd$), probably originating from some of the embedded sources previously observed in the$\rm H_2$near-infrared lines. At all other positions in the OMC-1 core, we estimate kinetic temperatures$\geq 80$ K and as high as 150 K at some positions around IRc2, from a simple Large-Velocity Gradient model.Comment: 10 pages, 3 figure

Regulon-Specific Control of Transcription Elongation across the Yeast Genome

Transcription elongation by RNA polymerase II was often considered an invariant non-regulated process. However, genome-wide studies have shown that transcriptional pausing during elongation is a frequent phenomenon in tightly-regulated metazoan genes. Using a combination of ChIP-on-chip and genomic run-on approaches, we found that the proportion of transcriptionally active RNA polymerase II (active versus total) present throughout the yeast genome is characteristic of some functional gene classes, like those related to ribosomes and mitochondria. This proportion also responds to regulatory stimuli mediated by protein kinase A and, in relation to cytosolic ribosomal-protein genes, it is mediated by the silencing domain of Rap1. We found that this inactive form of RNA polymerase II, which accumulates along the full length of ribosomal protein genes, is phosphorylated in the Ser5 residue of the CTD, but is hypophosphorylated in Ser2. Using the same experimental approach, we show that the in vivo–depletion of FACT, a chromatin-related elongation factor, also produces a regulon-specific effect on the expression of the yeast genome. This work demonstrates that the regulation of transcription elongation is a widespread, gene class–dependent phenomenon that also affects housekeeping genes

D-brane probes on L^{abc} Superconformal Field Theories

We study supersymmetric embeddings of D-brane probes of different dimensionality in the AdS_5xL^{abc} background of type IIB string theory. In the case of D3-branes, we recover the known three-cycles dual to the dibaryonic operators of the gauge theory and we also find a new family of supersymmetric embeddings. Supersymmetric configurations of D5-branes, representing fractional branes, and of spacetime filling D7-branes (which can be used to add flavor) are also found. Stable non supersymmetric configurations corresponding to fat strings and domain walls are found as well.Comment: 20 pages, LaTeX;v2: minor improvements, references adde

Nutrición del oso negro (Ursus americanus eremicus) en las serranías del Carmen, Coahuila

RESUMEN Se determinaron los componentes de la dieta del oso negro (Ursus americanus eremicus) en las serranías Maderas del Carmen, Coahuila. También se cuantificó la disponibilidad de los alimentos y su contenido de energía metabolizable. Se calcularon las necesidades energéticas de los osos y se estimó la capacidad de carga para esta especie. Se establecieron seis patrones estacionales de la dieta y se identificaron 28 componentes alimenticios, 92% de materia vegetal y 8% de materia animal. La capacidad de carga estimada para la etapa de máximos requerimientos energéticos de los osos es de 136 ha/ oso o 0.73 osos/km2. ABSTRACT The black bear (Ursus americanus eremicus) diet composition was determined in Maderas del Carmen Coahuila. The availability of the food was determined, as well as its metabolizable energy concentration. Black bear metabolizable energy requirements and carrying capacity were estimated. Six seasonal diet patterns were established. 28 food components were identified. 92% of the diet was vegetation and 8% animal matter. The estimated carrying capacity for Sierra del Carmen, Coahuila during the maximum bear energetic requirement phase is 136 ha/bear or 0.73 bears/km2

Identification of the water stress level in olive trees during pit hardening using the trunk growth rate indicator.

Water scarcity is generating an increasing interest in deficit irrigation scheduling. The trunk diameter fluctuations are daily cycles that have been suggested as tools for irrigation scheduling. The trunk growth rate (TGR) was suggested as the best indicator for olive trees during pit hardening. The aim of this work is to clarify how the TGR could be used to identify water stress levels. The experiment was performed during the 2017 season, in a commercial, super-high-density orchard in Carmona (Seville, Spain). Four different irrigation treatments were performed according to midday stem water potential values and TGR. The data obtained were very variable and both indicators presented a wide range of water status throughout the season. The maximum trunk diameter data clearly showed the pattern of the trees water status but the comparison between treatments and the identification of the water stress level was not possible. The average TGR was linked to the midday stem water potential, but with a minimum amount of data. Irrigation scheduling based on the average TGR was difficult because of the great increases in some daily TGR values. For clarity, the pool of data was grouped by midday stem water potential. These water stress levels were characterized using the weekly frequency of TGR values. The increase of water stress reduced the frequency of values between -0.1 and 0.3mm day-1 from 60% to less than 25%. Moderate water stress levels increased the percentage of values lower than -0.3mm day-1 from 7% to 37%. The most severe water stress conditions increased the TGR values between -0.3 and -0.1mm day-1 from 16% up to 22%.IRNASINSTITUTO DE LA GRASACSI

Cardiac resynchronization therapy and valvular cardiomyopathy after corrective surgery

Cardiac resynchronization therapy (CRT) has been shown to have clinical benefits in certain groups of patients with advanced heart failure (HF). However, patients with valvular cardiomyopathy are underrepresented in randomized clinical studies. The aim of this study was to assess the medium-term (i.e., at 6 months) effects of CRT in patients with HF exclusively due to valvular disease. The study included 40 consecutive patients who underwent CRT device implantation. At 6 months, there were improvements in functional class, left ventricular remodeling, and intraventricular dyssynchrony parameters in treated patients. In this particular subgroup of patients, the benefits of CRT were similar to those observed in patients with HF due to other etiologies

Positive culture in allograft ACL-reconstruction: what to do?

The transmission of disease or infection from the donor to the recipient is always a risk with the use of allografts. We carried out a research study on the behavioural pattern of implanted allografts, which were initially stored in perfect conditions (all cultures being negative) but later presented positive cultures at the implantation stage. Because there is no information available on how to deal with this type of situation, our aim was to set guidelines on the course of action which would be required in such a case. We conducted a retrospective study of 181 patients who underwent an ACL reconstruction using BPTB allografts. All previous bone and blood cultures and tests for hepatitis B and C, syphilis and HIV were negative. An allograft sample was taken for culture in the operating theatre just before its implantation. The results of the cultures were obtained 3-5 days after the operation. We had 24 allografts with positive culture (13.25%) after the implantation with no clinical infection in any of these patients. Positive cultures could be caused by undetected contamination while harvesting, storing or during manipulation before implantation. The lack of clinical signs of infection during the follow-up of our patients may indicate that no specific treatment-other than an antibiotic protocol-would be required when facing a case of positive culture of a graft piece after its implantation

Higher-order spectral analysis of stray flux signals for faults detection in induction motors

[EN] This work is a review of current trends in the stray flux signal processing techniques applied to the diagnosis of electrical machines. Initially, a review of the most commonly used standard methods is performed in the diagnosis of failures in induction machines and using stray flux; and then specifically it is treated and performed the algorithms based on statistical analysis using cumulants and polyspectra. In addition, the theoretical foundations of the analyzed algorithms and examples applications are shown from the practical point of view where the benefits that processing can have using HOSA and its relationship with stray flux signal analysis, are illustrated.This work has been supported by Generalitat Valenciana, Conselleria d'Educació, Cultura i Esport in the framework of the "Programa para la promoción de la investigación científica, el desarrollo tecnológico y la innovación en la Comunitat Valenciana", Subvenciones para grupos de investigación consolidables (ref: AICO/2019/224). J. Alberto Conejero is also partially supported by MEC Project MTM2016-75963-P.Iglesias Martínez, ME.; Antonino Daviu, JA.; Fernández De Córdoba, P.; Conejero, JA. (2020). Higher-order spectral analysis of stray flux signals for faults detection in induction motors. Applied Mathematics and Nonlinear Sciences. 5(2):1-14. https://doi.org/10.2478/amns.2020.1.00032S11452H. Akçay and E. Germen. 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