Viscothermal Losses in Double-Negative Acoustic Metamaterials

[EN] The influence of losses in double-negative metamaterial slabs recently introduced by Graciá-Salgado et al. [Phys. Rev. B 88, 224305 (2013)] is comprehensively studied. Viscous and thermal losses are considered in the linearized Navier-Stokes equations with no flow. Despite the extremely low thicknesses of boundary layers associated with each type of losses, the double-negative behavior is totally suppressed for the rigid structures under analysis. In other words, almost 100% of the energy transmitted into the slab is dissipated by viscothermal effects, in agreement with experimental data. Simulations undertaken for larger structures, using scale factors of up to 20 times, show that double-negative behavior is never recovered. The huge dissipation obtained by these structures leads us to propose them as interesting alternatives to conventional absorbers for specific situations, e.g., when treating low frequencies or when the excitation is narrow banded.V. M. G.-C. and J. S.-D. acknowledge the support from the Spanish Ministerio de Economia y Competitividad (MINECO), and the European Union Fondo Europeo de Desarrollo Regional (FEDER) through Project No. TEC 2014-53088-C3-1-R.Cutanda-Henriquez, V.; Garcia Chocano, VM.; Sánchez-Dehesa Moreno-Cid, J. (2017). Viscothermal Losses in Double-Negative Acoustic Metamaterials. Physical Review Applied. 8(1):014029-1-014029-12. doi:10.1103/PhysRevApplied.8.014029S014029-1014029-128

Some paradigms for visualizing parallel execution of logic programs

This paper addresses the design of visual paradigms for observing the parallel execution of logic programs. First, an intuitive method is proposed for arriving at the design of a paradigm and its implementation as a tool for a given model of parallelism. This method is based on stepwise reñnement starting from the deñnition of basic notions such as events and observables and some precedence relationships among events which hold for the given model of parallelism. The method is then applied to several types of parallel execution models for logic programs (Orparallelism, Determinate Dependent And parallelism, Restricted and-parallelism) for which visualization paradigms are designed. Finally, VisAndOr, a tool which implements all of these paradigms is presented, together with a discussion of its usefulness through examples

Implementation of an event driven scheme for visualizing parallel execution of logic programs

This article presents in an informal way some early results on the design of a series of paradigms for visualization of the parallel execution of logic programs. The results presented here refer to the visualization of or-parallelism, as in MUSE and Aurora, deterministic dependent and-parallelism, as in Andorra-I, and independent and-parallelism as in &-Prolog. A tool has been implemented for this purpose and has been interfaced with these systems. Results are presented showing the visualization of executions from these systems and the usefulness of the resulting tool is briefly discussed

Macroporous polymers tailored as supports for large biomolecules: Ionic liquids as porogenic solvents and as surface modifiers

Highly ordered rod-like polymeric monoliths with large-pores have been successfully synthesized using ionic liquids (ILs) IL-1 (1-Butyl-3-methylimidazolium bis (trifluoromethylsulfonyl)imide [BMIM][NTf2]) and IL-2 (1-octyl-3-methylimidazolium bis (trifluoromethylsulfonyl)imide [OMIM][NTf2]) as alternative porogenic solvents. The presence of ILs can not only promote the formation of a highly ordered macroporous structure, control the morphology of the polymer and control the chemical composition of surfaces for monoliths prepared from DVB. In this regard, post-functionalization of the monoliths can be easily achieved using the functional monomers introduced in the polymerization process or the unreacted vinyl groups present in the polymeric matrix. This control has allowed the preparation of monolithic Supported Ionic Liquid-like Phases (m-SILLPs) with excellent morphological properties. These m-SILLPs have been studied as supports for large biomolecules. Bioadsorption studies show that the adsorbed amount of protein reaches values as high as 150–200 mg of protein per gram of support

¿Es posible clasificar a los sujetos con afasia en base al enfoque neuropsicológico cognitivo?

158 p.Hoy en día, y a partir del enfoque cognitivo en el estudio de las afasias, se sabe que la variedad de pacientes afásicos es mayor de la que recoge la clasificación tradicional en síndromes, de ahí que el postulado más radical dé cuenta de que cada persona afásica es particular no pudiendo ser clasificada en forma precisa en un síndrome. El propósito de este estudio fue obtener evidencia en torno a la posibilidad de clasificar a los sujetos con afasia de acuerdo con el desempeño en un conjunto de tareas de procesamiento lingüístico. Para ello, se estudiaron los rendimientos de 30 sujetos, a partir del desempeño en distintas tareas que permitieron explorar la mayor parte de los procesos que intervienen en el lenguaje en todas sus modalidades, tanto oral como escrita y tanto en comprensión como en producción. Los resultados obtenidos dan cuenta de la conformación de subgrupos de sujetos afásicos, principalmente, a partir de tareas de repetición, denominación, lectura y procesamiento sintáctico. Estos hallazgos, se contrastan, por un lado, con la taxonomía afásica clásica y, por otro lado, con el postulado más radical del enfoque neuropsicolingüístico que señala que cada persona afásica es particular, no pudiendo ser clasificada. Palabras clave: procesamiento del lenguaje, afasia, clasificaciones./ABSTRACT:From a cognitive perspective in the study of aphasia, it is acknowledged that the current variety of aphasic patients is greater than that traditionally classified by syndrome. The more radical premise that each person with aphasia is unique, and cannot be adequately identified by syndrome has been proposed from this approach. The purpose of this study was to obtain evidence about the possibility to classify subjects with aphasia according to their performance on a set of language-processing tasks. To accomplish this goal we studied the performance of 30 subjects, based on their answers to many tasks covering all stages and modalities of language processing, particularly at the lexical and syntactic levels. We included verbal and written tasks, both at the receptive as well as expressive sublevels. According to the results, subgroups of aphasic subjects emerged. Tasks of repetition, naming, reading and syntactic processing showed a high discriminating value. These findings are contrasted, on one side with classical aphasia taxonomies, and on the other one with the more radical neuropsycholinguistic approach, according to which each person with aphasia is unique and cannot be classified in any way. Key terms: language processing, aphasia, taxonomies

Rose Bengal Immobilized on Supported Ionic‐Liquid‐like Phases: An Efficient Photocatalyst for Batch and Flow Processes

This is the peer reviewed version of the following article: Rose Bengal Immobilized on Supported Ionic‐Liquid‐like Phases: An Efficient Photocatalyst for Batch and Flow Processes, which has been published in final form at https://doi.org/10.1002/cssc.201901533. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.The catalytic activity of Rose Bengal (RB) immobilized on supported ionic liquid (IL)‐like phases was evaluated as a polymer‐supported photocatalyst. In these systems, the polymer was designed to play a pivotal role. The polymeric backbone adequately modified with IL‐like moieties (supported IL‐like phases, SILLPs) was not just an inert support for the dye but controlled the accessibility of reagents/substrates to the active sites and provided specific microenvironments for the reaction. The structure of SILLPs could be finetuned to adjust the catalytic efficiency of the RB‐SILLP composites, achieving systems that were more active and stable than the related systems in the absence of IL‐like units

Tuning lipase B from Candida antarctica C–C bond promiscuous activity by immobilization on poly-styrene-divinylbenzene beads

Lipase B from Candida antarctica (CALB) is able to catalyze C–C bond formation. After immobilization onto a hydrophobic PS-DVB support, the activity increases when compared to that of the soluble or tan – the commercially available Novozyme 435 (being up to 6 fold more active). Our results show that although this activity is not related to the catalytic group, the promiscuous activity of CALB may be tuned via immobilization. In addition, we have show that the secondary structure of both immobilized enzymes is quite different, using FT-ATR-IR spectroscopy

A proposal for an interchange abstract syntax for (parallel) Prolog

We propose an abstract syntax for Prolog that will help the manipulation of programs at compile-time, as well as the exchange of sources and information among the tools designed for this manipulation. This includes analysers, partial evaluators, and program transformation tools. We have chosen to concentrate on the information exchange format, rather than on the syntax of programs, for which we assume a simplified format. Our purpose is to provide a low-level meeting point for the tools which will allow them to read the same programs and understand the information about them. This report describes our first design in an informal way. We expect this design to evolve and concretize, along with the future development of the tools, during the project

Sublittoral soft bottom communities and diversity of Mejillones Bay in northern Chile (Humboldt Current upwelling system)

The macrozoobenthos of Mejillones Bay (23°S; Humboldt Current) was quantitatively investigated over a 7-year period from austral summer 1995/1996 to winter 2002. About 78 van Veen grab samples taken at six stations (5, 10, 20 m depth) provided the basis for the analysis of the distribution of 60 species and 28 families of benthic invertebrates, as well as of their abundance and biomass. Mean abundance (2,119 individuals m-2) was in the same order compared to a previous investigation; mean biomass (966 g formalin wet mass m-2), however, exceeded prior estimations mainly due to the dominance of the bivalve Aulacomya ater. About 43% of the taxa inhabited the complete depth range. Mean taxonomic Shannon diversity (H', Log e) was 1.54 ± 0.58 with a maximum at 20 m (1.95 ± 0.33); evenness increased with depth. The fauna was numerically dominated by carnivorous gastropods, polychaetes and crustaceans (48%). About 15% of the species were suspensivorous, 13% sedimentivorous, 11% detritivorous, 7% omnivorous and 6% herbivorous. Cluster analyses showed a significant difference between the shallow and the deeper stations. Gammarid amphipods and the polychaete family Nephtyidae characterized the 5-mzone, the molluscs Aulacomya ater, Mitrella unifasciata and gammarids the intermediate zone, while the gastropod Nassarius gayi and the polychaete family Nereidae were most prominent at the deeper stations. The communities of the three depth zones did not appear to be limited by hypoxia during non-El Niño conditions. Therefore, no typical change in community structure occurred during El Niño 1997–1998, in contrast to what was observed for deeper faunal assemblages and hypoxic bays elsewhere in the coastal Humboldt Current system

Novel glycopolymer hydrogels as mucosa-mimetic materials to reduce animal testing

Glycopolymer hydrogels capable of mimicking mucosal tissue in mucoadhesion testing have been designed. Liquid formulations containing mucoadhesive polymers were found to be retained on these tissues to the same extent as ex vivo gastric mucosa, when using a dynamic method of assessing mucoadhesion