1,767 research outputs found

    Strong Coupling of a Single Photon to a Magnetic Vortex

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    Strong light-matter coupling means that cavity photons and other types of matter excitations are coherently exchanged. It is used to couple different qubits (matter) via a quantum bus (photons) or to communicate different types of excitations, e.g., transducing light into phonons or magnons. A, so far, unexplored interface is the coupling between light and topologically protected particle-like excitations as magnetic domain walls, skyrmions, or vortices. Here, we show theoretically that a single photon living in a superconducting cavity can be strongly coupled to the gyrotropic mode of a magnetic vortex in a nanodisc. We combine numerical and analytical calculations for a superconducting coplanar waveguide resonator and different realizations of the nanodisc (materials and sizes). We show that, for enhancing the coupling, constrictions fabricated in the resonator are crucial, allowing to reach strong coupling in CoFe discs of radius 200-400 nm having resonance frequencies of a few GHz. The strong coupling regime permits coherently exchanging a single photon and quanta of vortex gyration. Thus, our calculations show that the device proposed here serves as a transducer between photons and gyrating vortices, opening the way to complement superconducting qubits with topologically protected spin-excitations such as vortices or skyrmions. We finish by discussing potential applications in quantum data processing based on the exploitation of the vortex as a short-wavelength magnon emitter

    Defining and Prototyping a Life-cycle for Dynamic Service Composition

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    Since the Internet has become a commodity in both wired and wireless environments, new applications and paradigms have emerged to explore this highly distributed and widespread system. One such paradigm is service-orientation, which enables the provision of software functionality as services, \ud allowing in this way the construction of distributed systems with loosely coupled parts. The Service-Oriented Architecture (SOA) provides a set of principles to create service-oriented systems, by defining how services can be \ud created, composed, published, discovered and invoked. In accordance with these principles, in this paper we address the challenge of performing dynamic service composition. The composition process and its associated tasks have to be precisely defined so that the different problems of dynamic service composition can be identified and tackled. To achieve this, this paper defines a life-cycle for dynamic service composition, which defines the required phases and stakeholders. Furthermore, we present our prototype in which the different phases of the dynamic service composition life-cycle are being implemented. This prototype is being used to experiment with and validate our initial ideas on dynamic service composition

    Fabrication and Characterization of Multiband Solar Cells Based on Highly Mismatched Alloys

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    Multiband solar cells are one type of third generation photovoltaic devices in which an increase of the power conversion efficiency is achieved through the absorption of low energy photons while preserving a large band gap that determines the open circuit voltage. The ability to absorb photons from different parts of the solar spectrum originates from the presence of an intermediate energy band located within the band gap of the material. This intermediate band, acting as a stepping stone allows the absorption of low energy photons to transfer electrons from the valence band to the conduction band by a sequential two photons absorption process. It has been demonstrated that highly mismatched alloys offer a potential to be used as a model material system for practical realization of multiband solar cells. Dilute nitride GaAs1-xNx highly mismatched alloy with low mole fraction of N is a prototypical multiband semiconductor with a well-defined intermediate band. Currently, we are using chemical beam epitaxy to synthesize dilute nitride highly mismatched alloys. The materials are characterized by a variety of structural and optical methods to optimize their properties for multiband photovoltaic devices

    Implementation of an extended ZINB model in the study of low levels of natural gastrointestinal nematode infections in adult sheep

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    Background: In this study, two traits related with resistance to gastrointestinal nematodes (GIN) were measured in 529 adult sheep: faecal egg count (FEC) and activity of immunoglobulin A in plasma (IgA). In dry years, FEC can be very low in semi-extensive systems, such as the one studied here, which makes identifying animals that are resistant or susceptible to infection a difficult task. A zero inflated negative binomial model (ZINB) model was used to calculate the extent of zero inflation for FEC; the model was extended to include information from the IgA responses. Results: In this dataset, 64 % of animals had zero FEC while the ZINB model suggested that 38 % of sheep had not been recently infected with GIN. Therefore 26 % of sheep were predicted to be infected animals with egg counts that were zero or below the detection limit and likely to be relatively resistant to nematode infection. IgA activities of all animals were then used to decide which of the sheep with zero egg counts had been exposed and which sheep had not been recently exposed. Animals with zero FEC and high IgA activity were considered resistant while animals with zero FEC and low IgA activity were considered as not recently infected. For the animals considered as exposed to the infection, the correlations among the studied traits were estimated, and the influence of these traits on the discrimination between unexposed and infected animals was assessed. Conclusions: The model presented here improved the detection of infected animals with zero FEC. The correlations calculated here will be useful in the development of a reliable index of GIN resistance that could be of assistance for the study of host resistance in studies based on natural infection, especially in adult sheep, and also the design of breeding programs aimed at increasing resistance to parasites

    Chileans facing immigration: Relations between orientations of acculturation, perception of threat and social well-being in the great concepcion

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    Indexación: Scopus; Scielo; Redalyc.En Chile, el aumento sostenido de la inmigración extranjera ha impactado en la construcción de nuevas formas de relación social. Si bien los procesos aculturativos han sido estudiados desde la perspectiva de los inmigrantes por numerosas investigaciones, los miembros de las sociedades receptoras han recibido menor atención. Este trabajo tiene como propósito identificar las preferencias de aculturación de N=553 chilenos, y verificar sus relaciones con la percepción de amenaza y el bienestar social. Contrario a lo esperado, el individualismo aculturativo se asoció con un menor grado de amenaza percibida y una mejor evaluación del propio funcionamiento social que el integracionismo. Estos hallazgos son relacionados con la incorporación de modelos de ciudadanía promovidos por la ideología neoliberal en el Chile post-dictatorial.In Chile, the sustained increase of migratory flows is producing an important impact on building new forms of social relations. Acculturation processes have been studied from immigrant’s perspective by numerous studies, but host majority members has received less attention from scholars. is study aimed to verify relations between acculturation preferences of N=553 Chilean participants, their social well-being and perceived threat. Results showed that, contrary as expected, individualism was positively linked with better social functioning and less perceived threat than integrationism, suggesting the impact of neoliberal ideology on post-dictatorial Chilean culture.http://www.redalyc.org/jatsRepo/647/64753989005/index.htm

    The new curricu1um for Pharmaceutical studies in the University of Granada

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    En el curso 1995-96 comienza un nuevo Plan de Estudios en Farmacia en la Universidad de Granada. Se hace una revisión sobre los anteriores planes de estudios que se han impartido en esta Facultad, comparándolos con el nuevo, se reseñan las principales caracteristicas del mismo y se le compara con los planes de estudios actualmente vigentes en otras facultades de farmacia en España.A new Curriculum designed for Pharmaeutical studies in instaured in the University of Granada during the Academic year 1995-96. A revision is made on the new curriculum comparing it to the previous one. The main characteristics are highlighted and it is also compared to the actual curricula of the different Faculties of Pharmacy in Spain

    Influence of processing conditions on microstructural, mechanical and tribological properties of graphene nanoplatelet reinforced UHMWPE

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    Ultra-high molecular weight polyethylene (UHMWPE) is a relevant thermoplastic in industry and a well-proven standard biomaterial in joint replacements. To enhance its tribological properties while preserving its bulk ones, composite coatings on a UHMWPE substrate were prepared using non-functionalised graphene nanoplatelet (GNP) at reinforcement concentration of 0.1–5 wt% and two mechanical mixing techniques (ball mill or blade mixer) with different consolidation temperatures of 175–240 °C. Changes in morphology and size of the UHMWPE particles before hot-pressing were observed in function of the mechanical mixing techniques applied. Wear rate was affected by graphene content, reaching a minimum at 0.5 wt% GNP, with a reduction of 20 and 15%, for ball milling and blade mixer, respectively. However, blade mixer increased the wear rate by around twice respect the ball milling results, for all the studied materials. The coefficient of friction decreased notably, by ~25%, below 3 wt% GNP content, and hardness increased by 24%, regardless of the mechanical mixing process used. Finally, consolidation temperature had a positive influence on wear rate at temperatures of around 195 °C, which could be related to the free radical scavenger effect of the GNP

    The mediated effect of social presence on social commerce WOM behavior

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    Based on expectation disconfirmation theory, this study analyzes how attitudes (satisfaction and loyalty) influence interaction intention (sWOM) and, consequently, active and passive sWOM behavior. It does so by assessing the mediating role of social presence on sWOM intention and behavior. The empirical results provide several contributions. First, knowing how to increase active sWOM contributes to bridging the gap regarding how to enhance interactions between users. Second, fostering active sWOM on social commerce websites will provide companies with more positive user-generated content, since this active sWOM comes from satisfied and loyal users, and it is assumed that they will rate the product positively and report a good experience. Third, companies can benefit more from users if users interact with other users by sharing their experiences. This study sheds light on how social presence can mediate the relationship between intention and behavior, particularly when it comes to increasing active participation and brand promotion. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

    Spanish reference values for the Breastfeeding Self-Efficacy Scale-Short Form BSES-SF

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    Fundamento. Describir los valores de referencia para la versión española de la Escala de Autoeficacia para la Lactancia Materna en su versión reducida (BSES-SF), considerando las diferencias según la experiencia previa en lactancia y la paridad. Metodología. Estudio transversal realizado en cinco hospitales de Alicante y uno de la Región de Murcia, con una muestra accidental de 949 mujeres que ofrecieron lactancia materna en el posparto, sin problemas médicos, propios o del recién nacido, que dificultaran la lactancia. Se obtuvieron datos sociodemográficos, obstétricos y sobre autoeficacia materna para la lactancia mediante la escala BSES-SF. Se calcularon datos de tendencia central, dispersión y percentiles de las puntuaciones de la escala BSES-SF para generar valores de referencia para toda la muestra y según la paridad y experiencia previa. Resultados. El nivel de autoeficacia fue significativamente menor (p<0,001) entre las mujeres primíparas (media =47,67±11,03) o sin experiencia previa (media =47,30±11,18) que entre las multíparas (media =52,87±10,66) o con experiencia anterior (media =53,93±9,93). La puntuación de los percentiles P25 y P75 de la escala BSES-SF fue, respectivamente, para toda la muestra de 42 y 59; para las mujeres sin hijos o sin experiencia previos de 39 y 56; para madres con hijos de 46 y 61; y para las madres con experiencia previa de 47 y 62. Conclusión. Los percentiles específicos obtenidos, según la paridad o la experiencia previa, pueden considerarse como valores de referencia para comparar el nivel de autoeficacia de un caso dado, evaluar intervenciones educativas y planificar intervenciones de apoyo durante el posparto.Background. To describe the reference values for the Spanish version of the Breastfeeding Self-Efficacy Scale-Short Form (BSES-SF), considering the differences according to parity and previous breastfeeding experience. Methods. Cross-sectional study in five hospitals in Alicante and one in Murcia, Spain, in a convenience sample of 949 in-hospital breastfeeding women, with no medical problems in the mothers or newborns hindering breastfeeding. Data on sociodemographic and obstetric variables, and on breastfeeding self-efficacy, using the BSES-SF, were collected. Central tendency, dispersion and percentile data were calculated to generate reference values for the entire sample, and by parity and previous experience. Results. The level of self-efficacy was significantly lower (p<0.001) among primiparous women (mean =47.67±11.03) or those without previous experience (mean =47.30±11.18) than among multiparas (mean =52.87±10.66) or women with previous experience (mean =53.93±9.93). The P25 and P75 percentiles for the BSES-SF were, respectively, 42 and 59 for the entire sample; 39 and 56 for women without children or without previous experience; 46 and 61 for mothers with children; and 47 and 62 for mothers with previous experience. Conclusions. The specific percentiles obtained by parity or previous experience should be considered the reference values for comparing the level of self-efficacy of a given case, and for evaluating educational interventions and planning postpartum support interventions.Este estudio recibió financiación del Ministerio de Ciencia e Innovación (nº de expediente PI09/90899)

    A methodological proposal and tool support for the HL7 standards compliance in the development of health information systems

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    Health information systems are increasingly complex, and their development is presented as a challenge for software development companies offering quality, maintainable and interoperable products. HL7 (Health level 7) International, an international non-profit organization, defines and maintains standards related to health information systems. However, the modelling languages proposed by HL7 are far removed from standard languages and widely known by software engineers. In these lines, NDT is a software development methodology that has a support tool called NDT-Suite and is based, on the one hand, on the paradigm of model-driven engineering and, on the other hand, in UML that is a widely recognized standard language. This paper proposes an extension of the NDT methodology called MoDHE (Model Driven Health Engineering) to offer software engineers a methodology capable of modelling health information systems conforming to HL7 using UML domain models
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