Fast Incoherent OFDR Interrogation of FBG Arrays Using Sparse Radio Frequency Responses

[EN] We present two implementations of fast, discrete incoherent optical frequency-domain reflectometers (I-OFDR) for the interrogation of equally spaced fiber Bragg grating (FBG) arrays, based on the determination of the array's radio frequency (RF) response at a sparse number of frequencies. FBG reflectivities are determined by use of the inverse discrete Fourier transform (IDFT) of the sparse RF response, in a dynamic range limited by crosstalk induced by FBG positioning errors. The first implementation employs the complete, vector RF response at a number of frequencies equal to the number N of FBGs in the array. In the second, the introduction of a reference reflector allows for an interrogation using the power (phaseless) RF response in 4N - 1 frequencies. Demodulation based on IDFT leads to total interrogation times determined by the network analyzer scan time, which can be as low as 10 mu s per FBG. Depending on the interrogation technique, electrical bandwidth requirements are 12 GHz in our array with 10-cm separation. We implemented both techniques in a N = 10 array, inducing decays in reflectivity by 10 dB in one or several FBGs. Unambiguous detection of FBG decays was obtained in both interrogation methods. Additional tests performed on the measured reflectivities also show that measurement linearity is preserved in the 10-dB decay range. As discrete I-OFDR systems, the proposed techniques show the possibility to reach compromises between interrogation time and dynamic range or accuracy in reflectivity measurements, using the number of interrogation frequencies and the sensor topology.This work was supported in part by Infraestructura GVA-FEDER operative program 2007-2013 and in part by the Spanish MINECO through Project TEC2017-88029-R. The work of J. Clement Bellido was supported by the GVA VALi+d scholarship ACIF/2016/214. The work of J. Hervas was supported by the Spanish MEC scholarship FPU13/04675.Clement, J.; Hervás-Peralta, J.; Madrigal-Madrigal, J.; Maestre, H.; Torregrosa, G.; Fernandez-Pousa, CR.; Sales Maicas, S. (2018). Fast Incoherent OFDR Interrogation of FBG Arrays Using Sparse Radio Frequency Responses. Journal of Lightwave Technology. 36(19):4393-4400. https://doi.org/10.1109/JLT.2018.2821199S43934400361

Nuevos conocimientos sobre la invernada y migración de la gaviota báltica Larus fuscus fuscus Linnaeus, 1758 (Charadriiformes: Laridae) en España

La gaviota sombría, Larus fuscus (Linnaeus, 1758), es una especie politípica cuya situación taxonómica sigue siendo revisada por parte de algunos científicos. La subespecie nominal Larus fuscus fuscus o “gaviota báltica” está considerada rareza en España, aunque desde hace más de una década cada año es observado algún ejemplar anillado. Esto nos ha llevado a actualizar su distribución espacial y temporal en España, usando datos de aves cuyos registros han sido aprobados o están bajo revisión del Comité de Rarezas de la Sociedad Española de Ornitología. Nuestros resultados sugieren que España constituye un área de invernada para una parte muy pequeña de la población, especialmente el área de Málaga, y que el período con mayor probabilidad de avistamientos es el de noviembre a marzo.Postprin

Revista de libros

Se reseñan los siguientes libros: - Benvenuto Terracini. Págine e Appunti di Lingüistica Storica. Editorial Felice Le Monnier. Firenze, 1957. Vol. rústica, 303 págs - Domingo A. Bravo: El quichua santiagueño (Reducto idiomático argentino). Ed. Universidad de Tucumán. Instituto de Letras, publicación N9 2, 1956. Vol. rústica, 400 página - Rafael Alberto Arrieta: La literatura argentina y sus vínculos con España. Colección Argirópolis. Librería y Editorial Uruguay. Buenos Aires, 1957. Volumen rústica, 205 páginas. - Alfredo D. Calcagno y Alfredo Eric Calcagno: Educación Democrática (segundo curso). Editorial Kapelusz, Buenos Aires, 1957. Volumen rústica, 282 páginas. - Risieri Frondizi: El punto de partida del filosofar (2a edición). Biblioteca Filosófica. Ed. Losada, Bs. Aires, 1957, 156 págs - H. H. Price: Hume’s theory of external world. Oxford Ap. The Clarendon Press (2* edición). Volumen encuadernado. 231 páginas - Juan Mantovani: La Crisis de la Educación. Editorial Columba. Colección Esquemas. Buenos Aires, 1957. Volumen rústica, 76 pág. - Fredrick H. Jungeann: La teoría del sustrato y los dialectos hispanorromances y gascones. Traducción de E. Alarcos Llorach. Editorial Gredos, Madrid, 1955. Volumen rústica de 454 páginasUniversidad Nacional de La Plat

Revista de libros

Se reseñan los siguientes libros: - Benvenuto Terracini. Págine e Appunti di Lingüistica Storica. Editorial Felice Le Monnier. Firenze, 1957. Vol. rústica, 303 págs - Domingo A. Bravo: El quichua santiagueño (Reducto idiomático argentino). Ed. Universidad de Tucumán. Instituto de Letras, publicación N9 2, 1956. Vol. rústica, 400 página - Rafael Alberto Arrieta: La literatura argentina y sus vínculos con España. Colección Argirópolis. Librería y Editorial Uruguay. Buenos Aires, 1957. Volumen rústica, 205 páginas. - Alfredo D. Calcagno y Alfredo Eric Calcagno: Educación Democrática (segundo curso). Editorial Kapelusz, Buenos Aires, 1957. Volumen rústica, 282 páginas. - Risieri Frondizi: El punto de partida del filosofar (2a edición). Biblioteca Filosófica. Ed. Losada, Bs. Aires, 1957, 156 págs - H. H. Price: Hume’s theory of external world. Oxford Ap. The Clarendon Press (2* edición). Volumen encuadernado. 231 páginas - Juan Mantovani: La Crisis de la Educación. Editorial Columba. Colección Esquemas. Buenos Aires, 1957. Volumen rústica, 76 pág. - Fredrick H. Jungeann: La teoría del sustrato y los dialectos hispanorromances y gascones. Traducción de E. Alarcos Llorach. Editorial Gredos, Madrid, 1955. Volumen rústica de 454 páginasUniversidad Nacional de La Plat

Revista de libros

Se reseñan los siguientes libros: - Benvenuto Terracini. Págine e Appunti di Lingüistica Storica. Editorial Felice Le Monnier. Firenze, 1957. Vol. rústica, 303 págs - Domingo A. Bravo: El quichua santiagueño (Reducto idiomático argentino). Ed. Universidad de Tucumán. Instituto de Letras, publicación N9 2, 1956. Vol. rústica, 400 página - Rafael Alberto Arrieta: La literatura argentina y sus vínculos con España. Colección Argirópolis. Librería y Editorial Uruguay. Buenos Aires, 1957. Volumen rústica, 205 páginas. - Alfredo D. Calcagno y Alfredo Eric Calcagno: Educación Democrática (segundo curso). Editorial Kapelusz, Buenos Aires, 1957. Volumen rústica, 282 páginas. - Risieri Frondizi: El punto de partida del filosofar (2a edición). Biblioteca Filosófica. Ed. Losada, Bs. Aires, 1957, 156 págs - H. H. Price: Hume’s theory of external world. Oxford Ap. The Clarendon Press (2* edición). Volumen encuadernado. 231 páginas - Juan Mantovani: La Crisis de la Educación. Editorial Columba. Colección Esquemas. Buenos Aires, 1957. Volumen rústica, 76 pág. - Fredrick H. Jungeann: La teoría del sustrato y los dialectos hispanorromances y gascones. Traducción de E. Alarcos Llorach. Editorial Gredos, Madrid, 1955. Volumen rústica de 454 páginasUniversidad Nacional de La Plat

Structure and reactivity of surface oxides on Pt(110) during catalytic CO oxidation

We present the first structure determination by surface x-ray diffraction during the restructuring of a model catalyst under reaction conditions, i.e., at high pressure and high temperature, and correlate the restructuring with a change in catalytic activity. We have analyzed the Pt(110) surface during CO oxidation at pressures up to 0.5 bar and temperatures up to 625 K. Depending on the O2/CO pressure ratio, we find three well-defined structures: namely, (i) the bulk-terminated Pt(110) surface, (ii) a thin, commensurate oxide, and (iii) a thin, incommensurate oxide. The commensurate oxide only appears under reaction conditions, i.e., when both O2 and CO are present and at sufficiently high temperatures. Density functional theory calculations indicate that the commensurate oxide is stabilized by carbonate ions (CO2−3). Both oxides have a substantially higher catalytic activity than the bulk-terminated Pt surface

Integrating clinicians, knowledge and data: expert-based cooperative analysis in healthcare decision support

<p>Abstract</p> <p>Background</p> <p>Decision support in health systems is a highly difficult task, due to the inherent complexity of the process and structures involved.</p> <p>Method</p> <p>This paper introduces a new hybrid methodology <it>Expert-based Cooperative Analysis </it>(EbCA), which incorporates explicit prior expert knowledge in data analysis methods, and elicits implicit or tacit expert knowledge (IK) to improve decision support in healthcare systems. EbCA has been applied to two different case studies, showing its usability and versatility: 1) Bench-marking of small mental health areas based on technical efficiency estimated by <it>EbCA-Data Envelopment Analysis (EbCA-DEA)</it>, and 2) Case-mix of schizophrenia based on functional dependency using <it>Clustering Based on Rules (ClBR)</it>. In both cases comparisons towards classical procedures using qualitative explicit prior knowledge were made. Bayesian predictive validity measures were used for comparison with expert panels results. Overall agreement was tested by Intraclass Correlation Coefficient in case "1" and kappa in both cases.</p> <p>Results</p> <p>EbCA is a new methodology composed by 6 steps:. 1) Data collection and data preparation; 2) acquisition of "Prior Expert Knowledge" (PEK) and design of the "Prior Knowledge Base" (PKB); 3) PKB-guided analysis; 4) support-interpretation tools to evaluate results and detect inconsistencies (here <it>Implicit Knowledg </it>-IK- might be elicited); 5) incorporation of elicited IK in PKB and repeat till a satisfactory solution; 6) post-processing results for decision support. EbCA has been useful for incorporating PEK in two different analysis methods (DEA and Clustering), applied respectively to assess technical efficiency of small mental health areas and for case-mix of schizophrenia based on functional dependency. Differences in results obtained with classical approaches were mainly related to the IK which could be elicited by using EbCA and had major implications for the decision making in both cases.</p> <p>Discussion</p> <p>This paper presents EbCA and shows the convenience of completing classical data analysis with PEK as a mean to extract relevant knowledge in complex health domains. One of the major benefits of EbCA is iterative elicitation of IK.. Both explicit and tacit or implicit expert knowledge are critical to guide the scientific analysis of very complex decisional problems as those found in health system research.</p

GC-MS Profile, Antioxidant Activity, and in Silico Study of the Essential Oil from Schinus molle L. Leaves in the Presence of Mosquito Juvenile Hormone-Binding Protein (mJHBP) from Aedes aegypti

Schinus molle is a medicinal plant used as an anti-inflammatory and for rheumatic pain in the traditional medicine of Peru. On the other hand, Aedes aegypti is the main vector of several tropical diseases and the transmitter of yellow fever, chikungunya, malaria, dengue, and Zika virus. In this study, the aim was to investigate the antioxidant activity in vitro and the insecticidal activity in silico, in the presence of the mosquito juvenile hormone-binding protein (mJHBP) from Aedes aegypti, of the essential oil from S. molle leaves. The volatile phytochemicals were analyzed by gas chromatography-mass spectrometry (GC-MS), and the profile antioxidants were examined by DPPH, ABTS, and FRAP assays. The evaluation in silico was carried out on mJHBP (PDB: 5V13) with an insecticidal approach. The results revealed that EO presented as the main volatile components to alpha-phellandrene (32.68%), D-limonene (12.59%), and beta-phellandrene (12.24%). The antioxidant activity showed values for DPPH=11.42±0.08 μmol ET/g, ABTS=134.88±4.37 μmol ET/g, and FRAP=65.16±1.46 μmol ET/g. Regarding the insecticidal approach in silico, alpha-muurolene and gamma-cadinene had the best biding energy on mJHBP (ΔG=-9.7 kcal/mol), followed by beta-cadinene (ΔG=-9.5 kcal/mol). Additionally, the volatile components did not reveal antioxidant activity, and its potential insecticidal effect would be acting on mJHBP from A. aegypti.Revisión por pare

Prácticas de física : laboratorio II

1 archivo PDF (86 páginas)Manual de laboratorio de prácticas de física