204 research outputs found
Extracting the infrared permittivity of SiO2 substrates locally by near-field imaging of phonon polaritons in a van der Waals crystal
Layered materials in which individual atomic layers are bonded by weak van der Waals forces (vdW materials) constitute one of the most prominent platforms for materials research. Particularly, polar vdW crystals, such as hexagonal boron nitride (h-BN), alpha-molybdenum trioxide (α-MoO3) or alpha-vanadium pentoxide (α-V2O5), have received significant attention in nano-optics, since they support phonon polaritons (PhPs)―light coupled to lattice vibrations― with strong electromagnetic confinement and low optical losses. Recently, correlative far- and near-field studies of α-MoO3 have been demonstrated as an effective strategy to accurately extract the permittivity of this material. Here, we use this accurately characterized and low-loss polaritonic material to sense its local dielectric environment, namely silica (SiO2), one of the most widespread substrates in nanotechnology. By studying the propagation of PhPs on α-MoO3 flakes with different thicknesses laying on SiO2 substrates via near-field microscopy (s-SNOM), we extract locally the infrared permittivity of SiO2. Our work reveals PhPs nanoimaging as a versatile method for the quantitative characterization of the local optical properties of dielectric substrates, crucial for understanding and predicting the response of nanomaterials and for the future scalability of integrated nanophotonic devices
Estimador competitivo de bajo coste computacional para deconvolución dispersa
This paper presents an efficient algorithm for computing
the maximum a posteriori (MAP) estimate of a Bernouilli-
Gaussian sequence distorted by a linear filter and corrupted by
noise. The computational effort for the MAP estimator increases
exponentially with the number of samples and is generally
unfeasible. The approach used by Kormylo and Mendel in their
pioneering work on the Single Most-Likely Replacement algorithm
(SMLR) has been the sub-optimal reference to evaluate the
efficiency of this new estimation method in computational effort
and detection probability. This algorithm reduces drastically
the SMLR computational load and allows real-time processing,
because only few samples of the observation data are required
by employing a windowing strategy. An extensive Monte Carlo
analysis, using synthetic data, has been performed to compare
the behaviour of the proposed estimators
Wnt pathway genes in osteoporosis and osteoarthritis: differential expression and genetic association study
Producción CientíficaIn comparison with hip fractures, increased
expression of genes in the Wnt pathway and increased
Wnt activity were found in bone samples and osteoblast
cultures from patients with osteoarthritis, suggesting the
involvement of this pathway in subchondral bone changes.
No consistent differences were found in the genetic
association study
Laboratory test system for small wind energy generators
This research work is devoted to the development of a set-up facility for testing Permanet-Magnet Synchronous-Machines (PMSM) used in small wind energy generators. The developed test system can be used not only for PMSM parameters characterization but also for the study of the performance of the power electronic associated to the electrical machine.This project is supported by the Instituto de Ingeniera y Tecnologa de Cantabria (ITEC) and the Cantabria Government under SODERCAN-INVESNOVA initiative
Análisis del desarrollo curricular de la Educación Física en la Enseñanza Secundaria Obligatoria: comparación de los currículos autonómicos : Analysis of curriculum development of Physical Education in Secondary Education: comparison of regional curricula
P. 82-87Tres fueron los objetivos de esta investigación: a) analizar el desarrollo curricular autonómico a partir del RD 1.105/2014 que establece el currículo básico de Educación Secundaria Obligatoria (ESO) en relación a la Educación Física (EF), b) comparar la carga horaria asignada a esta asignatura, y c) examinar las diferentes posibilidades que los currículos autonómicos han contemplado para incrementar la actividad física (AF) de los estudiantes en horario lectivo. Se realizó un análisis comparativo y cualitativo de las 15 normativas curriculares autonómicas disponibles. Los resultados muestran una elevada disparidad entre las autonomías en la manera de abordar los elementos curriculares. La catalogación de la EF como asignatura específica ha provocado serias divergencias, principalmente en los contenidos. Pese a las reiteradas reivindicaciones de los docentes y profesionales de la salud, la carga horaria se ha mantenido inmutable en relación a las leyes anteriores: dos horas semanales. Con todo, la consideración de propuestas en el marco de las asignaturas de libre configuración autonómica podría representar una vía eficaz para el incremento de la AF en los centros educativosS
Ensino de Robótica Móvel através da Realização de um Hackathon em ROS
[ES] El intercambio de ideas entre científicos y técnicos, tanto del ámbito académico como empresarial, es fundamental para facilitar el desarrollo de sistemas que puedan satisfacer las demandas de la sociedad actual. La transferencia de tecnología en este campo sigue siendo un reto y, por ello, este tipo de aportaciones se consideran de forma destacada en esta recopilación. Este libro trae debates y publicaciones sobre el desarrollo de técnicas innovadoras de problemas complejos de IoT. El programa técnico se centra tanto en la alta calidad como en la diversidad, con contribuciones en áreas de investigación bien establecidas y en evolución. Específicamente, 10 capítulos fueron presentados a este libro. Los editores alentaron y agradecieron particularmente las contribuciones sobre IA y computación distribuida en aplicaciones de IoT. Los editores agradecen especialmente el apoyo financiero del proyecto “Virtual-Ledgers-Tecnologías DLT/Blockchain y Cripto-IOT sobre organizaciones virtuales de agentes ligeros y su aplicación en la eficiencia en el transporte de última milla”, ID SA267P18, financiado por Junta de Castilla y León y fondos FEDER.[EN] The exchange of ideas between scientists and technicians, from both academic and business areas, is essential in order to ease the development of systems which can meet the demands of today’s society. Technology transfer in this field is still a challenge and, for that reason, this type of contributions are notably considered in this compilation. This book brings in discussions and publications concerning the development of innovative techniques of IoT complex problems. The technical program focuses both on high quality and diversity, with contributions in well-established and evolving areas of research. Specifically, 10 chapters were submitted to this book. The editors particularly encouraged and welcomed contributions on AI and distributed computing in IoT applications. The editors are specially grateful for the funding supporting by the project “Virtual-Ledgers-Tecnologías DLT/Blockchain y Cripto-IOT sobre organizaciones virtuales de agentes ligeros y su aplicación en la eficiencia en el transporte de última milla”, ID SA267P18, financed by regional government of Castilla y León and FEDER funds
Controlled Magnetic Anisotropy in Single Domain Mn-doped Biosynthesized Nanoparticles
Magnetotactic bacteria Magnetospirillum gryphiswaldense synthesize cubo-octahedral shaped magnetite nanoparticles, called magnetosomes, with a mean diameter of 40 nm. The high quality of the biosynthesized nanoparticles makes them suitable for numerous applications in fields like cancer therapy, among others.
The magnetic properties of magnetite magnetosomes can be tailored by doping them with transition metal elements, increasing their potential applications. In this work, we address the effect of Mn doping on the main properties of magnetosomes by the combination of structural and magnetic characterization techniques.
Energy-dispersive X-ray spectroscopy, X-ray absorption nearedge structure, and X-ray magnetic circular dichroism results reveal a Mn dopant percentage of utmost 2.3%, where Mn cations are incorporated as a combination of Mn2+ and Mn3+, preferably occupying tetrahedral and octahedral sites, respectively. Fe substitution by Mn notably alters the magnetic behavior of the doped magnetosomes. Theoretical modeling of the experimental hysteresis loops taken between 5 and 300 K with a modified Stoner-Wohlfarth approach highlights the different anisotropy contributions of the doped magnetosomes as a function of temperature. In
comparison with the undoped magnetosomes, Mn incorporation alters the magnetocrystalline anisotropy introducing a negative and larger cubic anisotropy down to the Verwey transition, which appears shifted to lower temperature values as a consequence of Mn doping. On the other hand, Mn-doped magnetosomes show a decrease in the uniaxial anisotropy in the whole temperature range, most likely associated with a morphological modification of the Mn-doped magnetosomes.The Spanish and Basque Governments are acknowledged for funding under project numbers MAT2017-
83631-C3-R and IT-1245-19, respectively
Unraveling heterogeneous susceptibility and the evolution of breast cancer using a systems biology approach
This is an Open Access article distributed under the terms of the Creative Commons Attribution License.-- et al.[Background]: An essential question in cancer is why individuals with the same disease have different clinical outcomes. Progress toward a more personalized medicine in cancer patients requires taking into account the underlying heterogeneity at different molecular levels. [Results]: Here, we present a model in which there are complex interactions at different cellular and systemic levels that account for the heterogeneity of susceptibility to and evolution of ERBB2-positive breast cancers. Our model is based on our analyses of a cohort of mice that are characterized by heterogeneous susceptibility to ERBB2-positive breast cancers. Our analysis reveals that there are similarities between ERBB2 tumors in humans and those of backcross mice at clinical, genomic, expression, and signaling levels. We also show that mice that have tumors with intrinsically high levels of active AKT and ERK are more resistant to tumor metastasis. Our findings suggest for the first time that a site-specific phosphorylation at the serine 473 residue of AKT1 modifies the capacity for tumors to disseminate. Finally, we present two predictive models that can explain the heterogeneous behavior of the disease in the mouse population when we consider simultaneously certain genetic markers, liver cell signaling and serum biomarkers that are identified before the onset of the disease. [Conclusions]: Considering simultaneously tumor pathophenotypes and several molecular levels, we show the heterogeneous behavior of ERBB2-positive breast cancer in terms of disease progression. This and similar studies should help to better understand disease variability in patient populations.JPL was partially supported by FEDER and MICINN (PLE2009-119), FIS (PI07/0057, PI10/00328, PIE14/00066), the Junta de Castilla y León (SAN673/SA26/08; SAN126/SA66/09, SA078A09, CSI034U13), the “Fundación Eugenio Rodríguez Pascual”, the Fundación Inbiomed (Instituto Oncológico Obra Social de la Caja Guipozcoa-San Sebastian, Kutxa), and the “Fundación Sandra Ibarra de Solidaridad frente al Cáncer”. AC was supported by MICINN (PLE2009-119). SCLL is funded by a JAEdoc Fellowship (CSIC)/FSE. MMSF and ABG are funded by fellowships from the Junta de Castilla y Leon. WR was supported by a Forschungsstipendium of the Deutsche Forschungsgemeinschaft (DFG) [RE 3108/1-1]. TN, BPB and DYL acknowledge support from the US Department of Energy Low-Dose SFA Program at Berkeley Lab [DE-AC02-05CH11231], the National Institutes of Health [RC1NS069177] and the California Breast Cancer Research Program [15IB-0063]. JHM was supported by the National Institutes of Health, a National Cancer Institute grant (R01 CA116481), and the Low-Dose Scientific Focus Area, Office of Biological and Environmental Research, US Department of Energy (DE-AC02-05CH11231).Peer Reviewe
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