10,115 research outputs found

    Observability of Linear Positive Dynamic Systems

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    Expression of homoeologous molecular systems in wheat alloploids

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    Allopolyploidy is widespread in the plant kingdom, where it has been of considerable evolutionary significance. Although the existence of heterotic interactions between the genomes that make up an alloploid have been generally assumed, the precise nature of these interactions has not been extensively investigated. Presently available evidence about metabolic integration of the wheat genomes is examined in search of new insights about the different modes of genome interaction. Although additive expression seems to be the case for many homoeologous systems, more complex patterns of integration have become evident. Examples of enzyme subunit complementation, gene compensation and other dosage effects, holoprotein completion, and complementation of metabolic pathways are discussed

    The largest oxigen bearing organic molecule repository

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    We present the first detection of complex aldehydes and isomers in three typical molecular clouds located within 200pc of the center of our Galaxy. We find very large abundances of these complex organic molecules (COMs) in the central molecular zone (CMZ), which we attribute to the ejection of COMs from grain mantles by shocks. The relative abundances of the different COMs with respect to that of CH3OH are strikingly similar for the three sources, located in very different environments in the CMZ. The similar relative abundances point toward a unique grain mantle composition in the CMZ. Studying the Galactic center clouds and objects in the Galactic disk having large abundances of COMs, we find that more saturated molecules are more abundant than the non-saturated ones. We also find differences between the relative abundance between COMs in the CMZ and the Galactic disk, suggesting different chemical histories of the grain mantles between the two regions in the Galaxy for the complex aldehydes. Different possibilities for the grain chemistry on the icy mantles in the GC clouds are briefly discussed. Cosmic rays can play an important role in the grain chemistry. With these new detections, the molecular clouds in the Galactic center appear to be one of the best laboratories for studying the formation of COMs in the Galaxy.Comment: 20 pages, 4 figures, accepted in Ap

    Independent confirmation and refined parameters of the hot Jupiter XO-5b

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    We present HATNet observations of XO-5b, confirming its planetary nature based on evidence beyond that described in the announcement of Burke et al. (2008), namely, the lack of significant correlation between spectral bisector variations and orbital phase. In addition, using extensive spectroscopic measurements spanning multiple seasons, we investigate the relatively large scatter in the spectral line bisectors. We also examine possible blended stellar configurations (hierarchical triples, chance alignments) that can mimic the planet signals, and we are able to show that none are consistent with the sum of all the data. The analysis of the S activity index shows no significant stellar activity. Our results for the planet parameters are consistent with values in Burke et al. (2008), and we refine both the stellar and planetary parameters using our data. XO-5b orbits a slightly evolved, late G type star with mass M_s = 0.88 +/- 0.03, radius R_s = 1.08 +/- 0.04, and metallicity close to solar. The planetary mass and radius are M_p = 1.059 +/- 0.028 M_Jup and R_p = 1.109 +/- 0.050 R_Jup, respectively, corresponding to a mean density of 0.96 -0.11 +0.14 g/cm^3. The ephemeris for the orbit is P = 4.187757 +/- 0.000011, E= 2454552.67168 +/- 0.00029 (BJD) with transit duration of 0.1307 +/- 0.0013 d. By measuring four individual transit centers, we found no signs for transit timing variations. The planet XO-5b is notable for its anomalously high Safronov number, and has a high surface gravity when compared to other transiting exoplanets with similar period.Comment: Accepted for publication in ApJ, 8 pages in emulateapj styl

    Celebrando los 50 años de la revista interamericana de psicologia/interamerican journal of psychology: un análisis de contenido

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    The Revista Interamericana de Psicologia/Interamerican Journal of Psychology (RIP/IJP) was first published in 1967. During its fifty-year history, the goal of the journal has been to promote collaboration and communication among psychologists on the Americas through the dissemination of theoretical and applied research. The authors reviewed 1,200 articles published in the RIP/IJP between 1967 and 2016 (Volumes 1-50). The articles were coded into seven main content categories, which included type of article, research design, sample characteristics, data collection strategies, data analysis, thematic analysis, and author’s characteristics and affiliations. Results indicated that up to date, 2,688 authors from 30 identified countries have contributed research on a diverse array of psychological topics on primarily three languages: Spanish, English, and Portuguese. Data also suggest these articles are characterized by a broad range of research methodologies, data collection procedures and analysis, and sample characteristics.La Revista Interamericana de Psicología/ /Interamerican Journal of Psychology (RIP/IJP) se publicó por primera vez en el 1967. Durante sus cincuenta años de historia, el objetivo de la revista ha sido promover la colaboración y la comunicación entre los psicólogos de las Américas a través de la difusion de investigaciones teoricas y aplicadas. Los autores revisaron 1.200 artículos publicados en el RIP/IJP entre 1967 y 2016 (volúmenes 1-50). Los artículos se codificaron en siete categorías principales de contenido que incluyeron el tipo de artículo, el diseño de la investigación, las características de la muestra, las estrategias de recopilación de datos, el análisis de datos, el análisis temático y las características y afiliaciones del autor. Los resultados indicaron que hasta la fecha, 2,688 autores de 30 países han contribuido con investigaciones sobre una gran variedad de temas psicológicos en principalmente tres idiomas: español, inglés y portugués. Los datos también sugieren que estos artículos se caracterizan por una amplia gama de metodologías de investigación, procedimientos y análisis de recopilación de datos y características de la muestra.Fil: Torres Fernandez, Ivelisse. New Mexico State University.; Estados UnidosFil: Polanco, Fernando Andrés. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Informática. Laboratorio Investigación y Desarrollo en Inteligencia Computacional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis; ArgentinaFil: Pereira, Steve R.. New Mexico State University.; Estados UnidosFil: Béria, Josiane Sueli. Universidad Nacional de San Luis. Facultad de Psicología. Departamento de Formación Profesional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis; ArgentinaFil: Zapico, Martín Gonzalo. Universidad Nacional de San Luis; Argentin

    An XMM-Newton and INTEGRAL view on the hard state of EXO 1745-248 during its 2015 outburst

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    CONTEXT - Transient low-mass X-ray binaries (LMXBs) often show outbursts lasting typically a few-weeks and characterized by a high X-ray luminosity (Lx10361038L_{x} \approx 10^{36}-10^{38} erg/sec), while for most of the time they are found in X-ray quiescence (LX10311033L_X\approx10^{31} -10^{33} erg/sec). EXO 1745-248 is one of them. AIMS - The broad-band coverage, and the sensitivity of instrument on board of {\xmm} and {\igr}, offers the opportunity to characterize the hard X-ray spectrum during {\exo} outburst. METHODS - In this paper we report on quasi-simultaneous {\xmm} and {\igr} observations of the X-ray transient {\exo} located in the globular cluster Terzan 5, performed ten days after the beginning of the outburst (on 2015 March 16th) shown by the source between March and June 2015. The source was caught in a hard state, emitting a 0.8-100 keV luminosity of 1037\simeq10^{37}~{\lumcgs}. RESULTS - The spectral continuum was dominated by thermal Comptonization of seed photons with temperature kTin1.3kT_{in}\simeq1.3 keV, by a cloud with moderate optical depth τ2\tau\simeq2 and electron temperature kTe40kT_e\simeq 40 keV. A weaker soft thermal component at temperature kTth0.6kT_{th}\simeq0.6--0.7 keV and compatible with a fraction of the neutron star radius was also detected. A rich emission line spectrum was observed by the EPIC-pn on-board {\xmm}; features at energies compatible with K-α\alpha transitions of ionized sulfur, argon, calcium and iron were detected, with a broadness compatible with either thermal Compton broadening or Doppler broadening in the inner parts of an accretion disk truncated at 20±620\pm6 gravitational radii from the neutron star. Strikingly, at least one narrow emission line ascribed to neutral or mildly ionized iron is needed to model the prominent emission complex detected between 5.5 and 7.5 keV. (Abridged)Comment: 14 pages, 6 figure, 2 tables. Accepted for publication on A&A (21/03/2017

    Cavity-backed slot array antenna in substrate-integrated waveguide technology

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    A slot array placed on the face of a cavity realized in substrate-integrated waveguide technology is presented. Guidelines to design similar antennas are provided. The design has been done with the help of commercial software. The result is a low-cost, directive array antenna with a single feeding microstrip-line

    HAT-P-12b: A Low-Density Sub-Saturn Mass Planet Transiting a Metal-Poor K Dwarf

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    We report on the discovery of HAT-P-12b, a transiting extrasolar planet orbiting the moderately bright V=12.8 K4 dwarf GSC 03033-00706, with a period P = 3.2130598 +- 0.0000021 d, transit epoch Tc = 2454419.19556 +- 0.00020 (BJD) and transit duration 0.0974 +- 0.0006 d. The host star has a mass of 0.73 +- 0.02 Msun, radius of 0.70 +- ^0.02_0.01 Rsun, effective temperature 4650 +- 60 K and metallicity [Fe/H] = -0.29 +- 0.05. We find a slight correlation between the observed spectral line bisector spans and the radial velocity, so we consider, and rule out, various blend configurations including a blend with a background eclipsing binary, and hierarchical triple systems where the eclipsing body is a star or a planet. We conclude that a model consisting of a single star with a transiting planet best fits the observations, and show that a likely explanation for the apparent correlation is contamination from scattered moonlight. Based on this model, the planetary companion has a mass of 0.211 +- 0.012 MJup, and a radius of 0.959 +- ^0.029_0.021 RJup yielding a mean density of 0.295 +- 0.025 g cm^-3. Comparing these observations with recent theoretical models we find that HAT-P-12b is consistent with a ~ 1-4.5 Gyr, mildly irradiated, H/He dominated planet with a core mass Mc <~ 10 Mearth. HAT-P-12b is thus the least massive H/He dominated gas giant planet found to date. This record was previously held by Saturn.Comment: Accepted for publication in ApJ, 13 pages, 9 figures, 5 table

    Knowledge, attitudes and preventive practices of primary health care professionals towards alcohol use: A national, cross-sectional study

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    Introduction Primary care (PC) professionals' knowledge about alcohol use has been identified as one of the barriers PC providers face in their clinic. Both PC professionals' level of training and attitude are crucial in the clinical practice regarding alcohol use. Objective To evaluate the knowledge, attitude, and preventive practices of Spanish PC physicians and nurses towards alcohol use. Design An observational, descriptive, cross-sectional, multi-center study. Methodology Location: PC centers of the Spanish National Health System (NHS). Participants: PC physicians and nurses selected randomly from health care centers, and by sending an e-mail to semFYC and SEMERGEN members. Healthcare providers completed an online survey on knowledge, attitude, and follow-up recommendations for reducing alcohol intake. A descriptive, bivariate, and multivariate statistical analysis was conducted (p<0.05). Results Participants: 1, 760 healthcare providers completed the survey (75.6% [95% CI 73.5-77.6] family physicians; 11.4% [95% CI 9.9-12.9] medical residents; and 12.5% [95% CI 10.9-14.1] nurses), with a mean age of 44.7 (SD 11.24, range: 26-64, 95% CI: 47.2-48.2). Knowledge was higher in family physicians (p<0.001), older professionals (Spearman's r = 0.11, p<0.001), and resident trainers (p<0.001). The PC professional most likely to provide advice for reducing alcohol use was: a nurse (p<0.001), female (p = 0.010), between 46 and 55 years old (p <0.001). Conclusions PC providers' knowledge and preventive practices regarding alcohol use are scarce, hence specific training strategies to increase their knowledge and improve their attitude and skills with regard to this health problem should be considered a healthcare policy priority
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