537 research outputs found

    Ferromagnetic proximity effect in a-Co_xSi_(1-x)/Nb bilayers: Role of magnetic disorder and interface transparency

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    The superconducting and magnetic properties of a-Co_(x)Si_(1−x) /Nb bilayers have been studied as a function of Co content in order to analyze the superconducting/ferromagnetic proximity effect in a system with strong disorder in the magnetic layers. As Co atoms become more diluted, the magnetization of the amorphous a-CoxSi1−x alloy decreases gradually, whereas their resistivity increases and enters in a weak localization regime. The superconducting transition temperatures of the a-Co_(x)Si_(1−x) /Nb bilayers follow a decreasing trend as Co content is reduced, reaching the lowest value at the boundary between the ferromagnetic-nonmagnetic amorphous phases. These results can be understood in terms of the increase in interface transparency together with the changes in the spin-flip scatterin

    Uprolides N, O and P from the Panamanian Octocoral Eunicea succinea.

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    Three new diterpenes, uprolide N (1), uprolide O (2), uprolide P (3) and a known one, dolabellane (4), were isolated from the CH₂Cl₂-MeOH extract of the gorgonian octocoral Eunicea succinea, collected from Bocas del Toro, on the Caribbean coast of Panama. Their structures were determined using spectroscopic analyses, including 1D and 2D NMR and high-resolution mass spectrometry (HRMS) together with molecular modeling studies. Compounds 1-3 displayed anti-inflammatory properties by inhibiting production of Tumor Necrosis Factor (TNF) and Interleukin (IL)-6 induced by lipopolysaccharide (LPS) in murine macrophages

    Coverage optimization and power reduction in SFN using simulated annealing

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    An approach that predicts the propagation, models the terrestrial receivers and optimizes the performance of single frequency networks (SFN) for digital video broadcasting in terms of the final coverage achieved over any geographical region, enhancing the most populated areas, is proposed in this paper. The effective coverage improvement and thus, the self-interference reduction in the SFN is accomplished by optimizing the internal static delays, sector antenna gain, and both azimuth and elevation orientation for every transmitter within the network using the heuristic simulated annealing (SA) algorithm. Decimation and elevation filtering techniques have been considered and applied to reduce the computational cost of the SA-based approach, including results that demonstrate the improvements achieved. Further representative results for two SFN in different scenarios considering the effect on the final coverage of optimizing any of the transmitter parameters previously outlined or a combination of some of them are reported and discussed in order to show both, the performance of the method and how increasing gradually the complexity of the model for the transmitters leads to more realistic and accurate results.This work was supported by the Spanish Ministry of Science and Innovation under Projects TEC2008-02730 and TEC2012-33321. The work of M. Lanza and Á. L. Gutiérrez was supported by a Pre-Doctoral Grant from the University of Cantabria

    Demographic and clinical characteristics of patients with α1-antitrypsin deficiency genotypes PI*ZZ and PI*SZ in the Spanish registry of EARCO

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    Spanish registry; Clinical characteristicsRegistre espanyol; Característiques clíniquesRegistro español; Características clínicasBackground The Spanish registry of α1-antitrypsin deficiency (AATD) integrated in the European Alpha-1 Research Collaboration (EARCO) provides information about the characteristics of patients, in particular those with the PI*SZ genotype, which is frequent in Spain. Method Individuals with severe AATD defined as proteinase inhibitor (PI) genotypes PI*ZZ, PI*SZ and other rare deficient variants were included from February 1, 2020, to February 1, 2022. The analysis focused on a comparison of the characteristics of PI*ZZ and PI*SZ patients. Results 409 patients were included (53.8% men) with a mean±sd age of 53.5±15.9 years. Genotypes were PI*ZZ in 181 (44.7%), PI*SZ in 163 (40.2%), PI*SS in 29 (7.2%) and other in 32 (7.9%). 271 (67.4%) had lung disease: 175 chronic obstructive pulmonary disease (43.5%), 163 emphysema (40.5%) and 83 bronchiectasis (20.6%). Patients with the PI*SZ genotype were younger, more frequently non-index cases and had a lower frequency of respiratory diseases except asthma compared with PI*ZZ patients. Among patients with respiratory diseases, PI*SZ individuals were significantly older both at onset of symptoms and at diagnosis; only asthma was more frequent in PI*SZ than in PI*ZZ individuals. Twelve PI*SZ patients (15.4%) received augmentation therapy compared with 94 PI*ZZ patients (66.2%; p<0.001). Conclusions There is a high prevalence of PI*SZ in Spain. Patients with the PI*SZ genotype were older at symptom onset and diagnosis and had less severe lung disease compared with PI*ZZ patients. The prevalence of asthma was higher in PI*SZ, and up to 15% of PI*SZ patients received augmentation therapy

    Desarrollo de mercados alimentarios en España: Análisis con el diamante de Porter

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    El propósito de este trabajo es analizar una perspectiva de creación de competencias en el desarrollo de creación de los mercados alimentarios, tomando como base España en dos períodos de tiempo significativos. Para este análisis se ha utilizado el modelo del Diamante de Porter. Este modelo considera que la ventaja de un mercado resulta de la interacción de cuatro factores, como son las condiciones de la demanda, la condición de competencia de los factores, las industrias de soporte y las estrategias, y rivalidad entre las compañías. Analizando los diferentes factores y su importancia, el modelo ayuda a detectar fortalezas y debilidades en los actores del mercado, y su cambio en el tiempo

    ChatGPT Challenges Blended Learning Methodologies in Engineering Education: A Case Study in Mathematics

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    [EN] This research aims to explore the potential impact of the ChatGPT on b-learning methodologies in engineering education, specifically in mathematics. The study focuses on how the use of these artificial intelligence tools can affect the acquisition of critical thinking, problem-solving, and group work skills among students. The research also analyzes the students' perception of the reliability, usefulness, and importance of these tools in academia. The study collected data through a survey of 110 students enrolled in a Mathematics I course in BEng Aerospace Engineering where a blended methodology, including flipped teaching, escape room gamification, problem-solving, and laboratory sessions and exams with a computer algebraic system were used. The data collected were analyzed using statistical methods and tests for significance. Results indicate students have quickly adopted ChatGPT tool, exhibiting high confidence in their responses (3.4/5) and general usage in the learning process (3.61/5), alongside a positive evaluation. However, concerns arose regarding the potential impact on developing lateral competencies essential for future engineers (2.8/5). The study concludes that the use of ChatGPT in blended learning methodologies poses new challenges for education in engineering, which requires the adaptation of teaching strategies and methodologies to ensure the development of essential skills for future engineers.This research was supported by Technical University of Valencia (UPV), "Convocatoria A + D, Proyectos de Innovación Mejora Educativa, grant number PIME/21-22/284".Sánchez Ruiz, LM.; Moll López, SE.; Núñez-Perez, A.; Moraño Fernández, JA.; Vega-Fleitas, E. (2023). ChatGPT Challenges Blended Learning Methodologies in Engineering Education: A Case Study in Mathematics. Applied Sciences. 13(10). https://doi.org/10.3390/app13106039131

    Transverse ratchet effect and superconducting vortices: simulation and experiment

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    A transverse ratchet effect has been measured in magnetic/ superconducting hybrid films fabricated by electron beam lithography and magnetron sputtering techniques. The samples are Nb films grown on top of an array of Ni nanotriangles. Injecting an ac current parallel to the triangle reflection symmetry axis yields an output dc voltage perpendicular to the current, due to a net motion of flux vortices in the superconductor. The effect is reproduced by numerical simulations of vortices as Langevin particles with realistic parameters. Simulations provide an intuitive picture of the ratchet mechanism, revealing the fundamental role played by the random intrinsic pinning of the superconductor

    Plasmonic nanodevice with magnetic funcionalities: fabrication and characterization

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    We have designed and fabricated a nanodevice exhibiting simultaneously ferromagnetic properties of nanostructures with plasmonic properties of continuous films. Our device consists of an array of nanomagnets on top of a continuous plasmonic film. The patterned nanomagnets magnetic state is single domain and well-defined shape anisotropy. Despite the presence of the patterned media on top of the Au film, the system exhibits surface plasmon resonance characteristics of a continuous film, i.e., propagating surface plasmon-polaritons

    On the applicability of ray-tracing propagation models to V2V-intersection environments

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    In this work, we analyze the applicability of a geometric-based stochastic (GBS) model based on ray-tracing techniques to vehicular-to-vehicular (V2V) intersections. The accuracy and usefulness of the proposed model is analyzed using simulated results and narrowband channel measurements at 5.9 GHz. The results show that these type of models can be a good choice to evaluate communications protocols and system performance of future vehicular networks

    COVID-19’s impact on care practice for alpha-1-antitrypsin deficiency patients

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    Alpha-1-antitrypsin deficiency; COVID-19; Patient managementDeficiencia de alfa-1-antitripsina; COVID-19; Gestión del pacienteDeficiència d'alfa-1-antitripsina; COVID-19; Gestió del pacientBackground Patients with alpha-1 antitrypsin deficiency (AATD), commonly categorized as a rare disease, have been affected by the changes in healthcare management brought about by COVID-19. This study’s aim was to identify the changes that have taken place in AATD patient care as a result of the COVID-19 pandemic in Spain and to propose experts’ recommendations aimed at ensuring humanized and quality care for people with AATD in the post-pandemic situation. Methods A qualitative descriptive case study with a holistic single-case design was conducted, using focus groups with experts in AATD clinical management, including 15 health professionals with ties to the Spanish health system (12 pneumologists and 2 hospital pharmacists from 11 different hospitals in Spain) and 1 patient representative. Results COVID-19 has had a major impact on numerous aspects of AATD clinical patient management in Spain, including diagnostic, treatment, and follow-up phases. The experts concluded that there is a need to strengthen coordination between Primary Care and Hospital Care and improve the coordination processes across all the organizations and actors involved in the healthcare system. Regarding telemedicine and telecare, experts have concluded that it is necessary to promote this methodology and to develop protocols and training programs. Experts have recommended developing personalized and precision medicine, and patient participation in decision-making, promoting self-care and patient autonomy to optimize their healthcare and improve their quality of life. The possibility of monitoring and treating AATD patients from home has also been proposed by experts. Another result of the study was the recommendation of the need to ensure that plasma donations are made on a regular basis by a sufficient number of healthy individuals. Conclusion The study advances knowledge by highlighting the challenges faced by health professionals and changes in AATD patient management in the context of the COVID-19 pandemic. It also proposes experts’ recommendations aimed at ensuring humanized and quality care for people with AATD in the post-pandemic situation. This work could serve as a reference study for physicians on their daily clinical practice with AATD patients and may also provide guidance on the changes to be put in place for the post-pandemic situation.This study was funded by CSL Behring
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