2,088 research outputs found

    Detection of the secondary eclipse of Qatar-1b in the Ks band

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    Qatar-1b is a close-orbiting hot Jupiter (Rp1.18R_p\simeq 1.18 RJR_J, Mp1.33M_p\simeq 1.33 MJM_J) around a metal-rich K-dwarf, with orbital separation and period of 0.023 AU and 1.42 days. We have observed the secondary eclipse of this exoplanet in the Ks band with the objective of deriving a brightness temperature for the planet and providing further constraints to the orbital configuration of the system. We obtained near-infrared photometric data from the ground by using the OMEGA2000 instrument at the 3.5 m telescope at Calar Alto (Spain) in staring mode, with the telescope defocused. We have used principal component analysis (PCA) to identify correlated systematic trends in the data. A Markov chain Monte Carlo analysis was performed to model the correlated systematics and fit for the secondary eclipse of Qatar-1b using a previously developed occultation model. We adopted the prayer bead method to assess the effect of red noise on the derived parameters. We measured a secondary eclipse depth of 0.196%0.051%+0.071%0.196\%^{+0.071\%}_{-0.051\%}, which indicates a brightness temperature in the Ks band for the planet of 1885168+2121885^{+212}_{-168} K. We also measured a small deviation in the central phase of the secondary eclipse of 0.00790.0043+0.0162-0.0079^{+0.0162}_{-0.0043}, which leads to a value for ecosωe\cos{\omega} of 0.01230.0067+0.0252-0.0123^{+0.0252}_{-0.0067}. However, this last result needs to be confirmed with more data.Comment: 6 pages, 6 figures, accepted for publication in A&

    Blockchain-Based Services Implemented in a Microservices Architecture Using a Trusted Platform Module Applied to Electric Vehicle Charging Stations

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    Microservice architectures exploit container-based virtualized services, which rarely use hardware-based cryptography. A trusted platform module (TPM) offers a hardware root for trust in services that makes use of cryptographic operations. The virtualization of this hardware module offers high usability for other types of service that require TPM functionalities. This paper proposes the design of TPM virtualization in a container. To ensure integrity, different mechanisms, such as attestation and sealing, have been developed for the binaries and libraries stored in the container volumes. Through a REST API, the container offers the functionalities of a TPM, such as key generation and signing. To prevent unauthorized access to the container, this article proposes an authentication mechanism based on tokens issued by the Cognito Amazon Web Service. As a proof of concept and applicability in industry, a use case for electric vehicle charging stations using a microservice-based architecture is proposed. Using the EOS.IO blockchain to maintain a copy of the data, the virtualized TPM microservice provides the cryptographic operations necessary for blockchain transactions. Through a two-factor authentication mechanism, users can access the data. This scenario shows the potential of using blockchain technologies in microservice-based architectures, where microservices such as the virtualized TPM fill a security gap in these architectures.Infineon TechnologiesProgram “Digitalisierung der EnergiewendeBundesministeriums für Wirtschaft und EnergieTrusted Blockchains fur das offene, intelligente Energienetz der Zukunft (tbiEnergy)FKZ 03EI6029DEuropean Health and Digital Executive Agency (HaDEA) program under Grant Agreement No 101092950 (EDGELESS project)FEDER/Junta de Andalucia-Consejeria de Transformacion Economica, Industria, Conocimiento y Universidades under Project B-TIC-588-UGR20

    Caracterización del Sistema Kárstico de Olalde a partir del análisis del hidrograma del manantial

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    The Olalde spring is the main drain of the karstic system of the Iimestome of San Miguel de Ereñozar; the aquifer is also recharged through sinks (ponors), by the surface run off from drained closed basins, partially occupied by impermeable materials. The mean flow of the spring is 240 I/sec, with a very high variability: the flow was 2633 I/sec at the beginning of the recession curve analyzed here and 18 I/sec the last day considered. The value of the depletion coefficient α is 0.032 day-1 and the duration of the recession curve "sensu stricto" is 21.5 days. The values of the velocity of infiltration coefficient ἠ and the heterogeneity coefficient ξ are, respectively, 0.0465 and 3.49 day-1. The parameters i (=0.114) and k (=0.025) suggest a very fast recession and a very poor regulation power; this behaviour is typical of intensely karstified systems with a very well developed subterranean drainage network which are characteristic of the realm of huge spelaeological caves. These facts reveal that the prospects of regulation of the spring are not very promising and would involve, in any case, a small part of the whole discharge.El manantial de Olalde es la principal surgencia del sistema kárstico constituido por las calizas de San Miguel de Ereñozar; el acuífero es recargado además, a través de sumideros, por la escorrentía superficial de cuencas endorreicas ocupadas parcialmente por materiales impermeables. El caudal medio del manantial es de 240 l/seg con una notable variabilidad: el caudal era de 2633 l/seg al comienzo de la decrecida estudiada en este trabajo y de 18 l/seg el último día considerado. El coeficiente de agotamiento α tiene un valor de 0.032 día-1 y la duración de la decrecida propiamente dicha es de 21,5 días. Los valores del coeficiente de velocidad de infiltración ἠ y del coeficiente del heterogeneidad ξ son, respectivamente, 0.0465 -1 día y 3,49-1 día. Los parámetros i (=0.114) y k (=0.025) indican una decrecida muy rápida y un escaso poder regulador, lo que corresponde a sistemas muy karstificados con redes de drenaje subterráneo muy desarrolladas, propias del dominio de las redes espeleológicas. Todo ello pone de manifiesto unas perspectivas de regulación del manantial poco favorables y que, en todo caso, afectarían a una pequeña fracción de las aportaciones totales

    Estudio del comportamiento electroquímico en baterías de litio de nanopartículas de Li2NiTiO4

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    III Encuentro sobre Nanociencia y Nanotecnología de Investigadores y Tecnólogos Andaluce

    3-Amino­pyridin-1-ium 3-carb­oxy­benzo­ate

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    In the title organic salt, C5H7N2 +·C8H5O4 −, the carb­oxy­lic group is nearly coplanar with the benzene ring [dihedral angle 1.9 (4)°] whereas the carboxyl­ate group is twisted relative to the benzene ring by 13.6 (4)°. In the crystal, N-H⋯O and O—H⋯O hydrogen bonds connect the components into a three-dimensional framework consisting of stacks of alternating pairs of anions and cations exhibiting π–π stacking inter­actions with centroid–centroid distances in the range 3.676 (2)–3.711 (1) Å. The π–π stacks extend along [110] and [-110]

    Fenoles de interés farmacológico en hojas de vides silvestres (Vitis spp.) de México

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    Sedentary styles of life, along with inadequate nutritional habits, increase the risk to develop degenerative chronic diseases. Searching for possible alternatives of prevention for those risks, it has been investigated about the quality and nutraceutic properties of several agricultural commodities. The phenols are substances with important functions in vegetal organisms; and moreover they have antioxidants properties in the cellular metabolism of humans and animals. In order to quantify the content of three phenolic acids and a stilbene, it was performed analyses, by high performance liquid chromatography (HPLC-UV/Vis), on metanolic leave extracts of 97 wild grapevines (Vitis spp.) of Puebla, Mexico. Those plants were found growing in their natural environments from 207 to 2175 m. The gallic acid was the most common of the metabolites since it appeared in 96 of the 97 samples, rutin was the second most common substance and it was identified in 80 samples, the caffeic acid appeared in 29 and finally resveratrol only in 14. The leaves of wild grapevines contain diverse antioxidants substances that might have several benefits in the human health; in addition the suitable conservation, maintenance and correct advantage of this plant genus provide environmental services and the balance of ecosystems

    Effect of boron addition on the electrochemical properties of LiFePO4

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    III Encuentro sobre Nanociencia y Nanotecnología de Investigadores y Tecnólogos Andaluce

    Resveratrol content in leaves of Mexican wild grapevines (Vitis spp.)

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    El resveratrol es considerado una fitoalexina pues es sintetizado como respuesta a patógenos (factores bióticos) y en condiciones climáticas adversas (factores abióticos). Actualmente existe mucho interés en él por su potencial uso en farmacología como antioxidante. Mediante cromatografía de líquidos de alta resolución (HPLC) se determinó el contenido de resveratrol en hojas de 18 accesiones de vides nativas de Puebla, México, cuatro de ellas creciendo en cuatro condiciones ambientales diferentes. Las concentraciones fueron muy variables, estimándose 39,5 μg g−1 peso fresco como valor máximo, mientras que en algunas accesiones no fue posible detectar resveratrol. Se observaron diferencias en el contenido de resveratrol para accesiones creciendo en localidades diferentes, lo que sugiere alta influencia de los factores ambientales sobre la expresión del genotipo en la inducción o inhibición de la biosíntesis de dicho metabolito secundario.Resveratrol is considered a phytoalexin, because it is synthesized in response to pathogens (biotic factors) and adverse climatic conditions (abiotic factors). Nowadays there is great interest in this substance, due to its potential use in pharmacology as an antioxidant. Through high performance liquid chromatography (HPLC), resveratrol content was determined in leaves of 18 accessions of wild grapevines native to Puebla, Mexico; four of them growing in four different environmental conditions. There was high variability in the resveratrol contents, estimating 39.5 μg g-1 fresh weight as maximum value whereas in some accessions there was not detection. Differences in the content of resveratrol within the four environments for the different accessions were observed, suggesting high influence of the environment on the genotype, inducting or inhibiting the biosynthesis of that compound.Fil: Tobar-Reyes, J. Refugio. Benemérita Universidad Autónoma de México. Escuela de Ingeniería AgrohidraúlicaFil: Franco-Mora, Omar. Universidad Autónoma del Estado de México. Facultad de Ciencias AgrícolasFil: Morales-Rosales, Edgar Jesús. Universidad Autónoma del Estado de México. Facultad de Ciencias AgrícolasFil: Cruz-Castillo, Juan Guillermo. Universidad Autónoma Chapingo (México). Centro Regional Universitario Orient

    In situ photoacoustic spectroscopy of phycobiliproteins in Gracilaria chilensis

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    peer reviewedPhycobiliproteins, the main polypeptidic components of the phycobilisomes (PBS), are biolog- ical macromolecules arranged in complex interaction systems to perform light harvesting and conduction. The optical properties of these systems can hardly be studied by conventional spectroscopic techniques. Furthermore this techniques also involve laborious chemical extraction methods. Photoacoustic (PA) spec- troscopy was successfully applied to an in situ study of the phycobiliproteins expression in the eukaryotic red algae: Gracilaria chilensis
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