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Argentina is the world's leading exporter of confectionery sunflower. This work characterized the morphometric and nutritional composition of sunflower seeds from new confectionery genotypes. Average morphometric variables per seed were: weight 0.11 and 0.06 g with and without achene, respectively; length 15.2 mm; and width 8.50 mm, with most calibers greater than 9.51 mm. Proximate analysis indicated that seeds without shell were an important source of lipids (49 %), as well as proteins (28 %), carbohydrates (11 %), and minerals (4.8 % ashes). Fatty acid composition showed that polyunsaturated fatty acids were the major components (56 %), followed by monounsaturated ones (34 %), and saturated ones (11 %). The mid-oleic genotype developed by INTA showed significantly greater oleic acid (47 %) and lower linoleic acid (42 %) than the commercial hybrid. Proteic composition showed 33 % of essential amino acids (EAA) while fiber and sugars represented 3.9 % and 7.3 % respectively; macroelements such as K, Mg and Ca, and microelements such as Mn, Fe, Cu, Zn, Se, Co, Mo and Na. New confectionery sunflower hybrids developed by INTA stand out for their high quality in edible oil, proteins and essential components, all very valuable for the food industry.

Quasar projected pairs (QPPs) can be used for investigating the circumgalactic medium of quasars through the study of intervening absorption lines in the spectrum of the background quasar that are at the same redshift of the foreground quasar. Here we report on optical spectroscopy, gathered at Gran Telescopio Canarias, of 14 QPPs. In 7 cases we find MgII absorption lines associated with the foreground quasar. Only for two cases line-of-sight absorptions (LOS) are revealed. These new observations complement our previous study performed on other 30 QPPs. A brief discussion of the properties of the intervening absorption lines associated with the foreground quasar for the full dataset is reported., 9 pages, 5 figures, accepted for publication in Astrophysics and Space Science

Temporal analysis of blazar flux is a powerful tool to draw inferences about the emission processes and physics of these sources. In the most general case, the available light curves are irregularly sampled and influenced by gaps, and in addition are also affected by correlated noise, making their analysis complicated. Gaussian processes may offer a viable tool to assess the statistical significance of proposed periods in light curves characterized by any sampling and noise pattern. We infer the significance of the periods proposed in the literature for two well known blazars with multiple claims of possible year-long periodicity: PG1553+113 and PKS2155-304, in the high-energy and optical bands. Adding a periodic component to the modeling gives a better statistical description of the analyzed light curves. The improvement is rather solid for PG1553+113, both at high energies and in the optical, while for PKS2155-304 at high energies the improvement is not yet strong enough to allow cogent claims, and no evidence for periodicity emerged by the analysis in the optical. Modeling a light curve by means of Gaussian processes, in spite of being relatively computationally demanding, allows us to derive a wealth of information about the data under study and suggests an original analysis framework for light curves of astrophysical interest., Comment: Astronomical Journal, in press

PKS 1510-089 is a flat spectrum radio quasar strongly variable in the optical and GeV range. To date, very high-energy (VHE, > 100 GeV) emission has been observed from this source either during long high states of optical and GeV activity or during short flares. Aims. We search for low-state VHE gamma-ray emission from PKS 1510-089. We characterize and model the source in a broadband context, which would provide a baseline over which high states and flares could be better understood. Methods. PKS 1510-089 has been monitored by the MAGIC telescopes since 2012. We use daily binned Fermi-LAT flux measurements of PKS 1510-089 to characterize the GeV emission and select the observation periods of MAGIC during low state of activity. For the selected times we compute the average radio, IR, optical, UV, X-ray, and gamma-ray emission to construct a low-state spectral energy distribution of the source. The broadband emission is modeled within an external Compton scenario with a stationary emission region through which plasma and magnetic fields are flowing. We also perform the emission-model-independent calculations of the maximum absorption in the broad line region (BLR) using two different models. Results. The MAGIC telescopes collected 75 hr of data during times when the Fermi-LAT flux measured above 1 GeV was below 3? × 10 -8 ? cm -2 ? s -1 , which is the threshold adopted for the definition of a low gamma-ray activity state. The data show a strongly significant (9.5¿) VHE gamma-ray emission at the level of (4.27 ± 0.61 stat ) × 10 -12 ? cm -2 ? s -1 above 150 GeV, a factor of 80 lower than the highest flare observed so far from this object. Despite the lower flux, the spectral shape is consistent with earlier detections in the VHE band. The broadband emission is compatible with the external Compton scenario assuming a large emission region located beyond the BLR. For the first time the gamma-ray data allow us to place a limit on the location of the emission region during a low gamma-ray state of a FSRQ. For the used model of the BLR, the 95% confidence level on the location of the emission region allows us to place it at a distance > 74% of the outer radius of the BLR. © ESO 2018., The financial support of the German BMBF and MPG, the Italian INFN and INAF, the Swiss National Fund SNF, the ERDF under the Spanish MINECO (FPA2015-69818-P, FPA2012-36668, FPA2015-68378-P, FPA2015-69210-C6-2-R, FPA2015-69210-C6-4-R, FPA2015-69210-C6-6-R, AYA2015-71042-P, AYA2016-76012-C3-1-P, ESP2015-71662-C2-2-P, CSD2009-00064), and the Japanese JSPS and MEXT is gratefully acknowledged. This work was also supported by the Spanish Centro de Exce-lencia “Severo Ochoa” SEV-2012-0234 and SEV-2015-0548, and Unidad de Excelencia “María de Maeztu” MDM-2014-0369, by the Croatian Science Foundation (HrZZ) Project IP-2016-06-9782 and the University of Rijeka Project 13.12.1.3.02, by the DFG Collaborative Research Centers SFB823/C4 and SFB876/C3, the Polish National Research Centre grant UMO-2016/22/M/ST9/00382, and by the Brazilian MCTIC, CNPq and FAPERJ. IA acknowledges support from a Ramón y Cajal grant of the Ministerio de Economía, Industria, y Competitividad (MINECO) of Spain. Acquisition and reduction of the POLAMI and MAPCAT data was supported in part by MINECO through grants AYA2010-14844, AYA2013-40825-P, and AYA2016-80889-P, and by the Regional Government of Andalucía through grant P09-FQM-4784.

Blazars are a sub-population of quasars whose jets are nearly aligned with the line-of-sight, which tend to exhibit multi-wavelength variability on a variety of timescales. Quasi-periodic variability on year-like timescales has been detected in a number of bright sources, and has been connected to the orbital motion of a putative massive black hole binary. If this were indeed the case, those blazar binaries would contribute to the nanohertz gravitational-wave stochastic background. We test the binary hypothesis for the blazar population observed by the \textit{Fermi} Gamma-Ray Space Telescope, which consists of BL Lacertae objects and flat-spectrum radio quasars. Using mock populations informed by the luminosity functions for BL Lacertae objects and flat-spectrum radio quasars with redshifts $z \le 2$, we calculate the expected gravitational wave background and compare it to recent pulsar timing array upper limits. The two are consistent only if a fraction $\lesssim 10^{-3}$ of blazars hosts a binary with orbital periods $, 5 pages, 4 figures, accepted by MNRAS Letters

We review the reports of possible year-long quasi-periodicities of BL Lac objects in the γ-ray and optical bands, and present a homogeneous time analysis of the light curves of PKS2155−304, PG1553+113, and BL Lac. Based on results from a survey covering the entire Fermi γ-ray sky we have estimated the fraction of possible quasi-periodic BL Lac objects. We compared the cyclical behaviour in BL Lac objects with that derived from the search of possible optical periodicities in quasars, and find that at z ≲ 1 the cosmic density of quasi-periodic BL Lac objects is larger than that of quasi-periodic quasars. If the BL Lac quasi-periodicities were due to a supermassive binary black hole (SBBH) scenario, there could be a tension with the upper limits on the gravitational wave background measured by the pulsar timing array. The argument clearly indicates the difficulties of generally associating quasi-periodicities of BL Lac objects with SBBHs.

We investigate the environments of galaxies around BL Lac objects and FR I radiogalaxies, the alleged parent populations of misaligned sources. We compare the environment of a sample of 50 BL Lac objects at 0.1, Comment: $ pages, 4 figures, accepted for publication in Monthly Notices of the Royal Astronomical Society Letters

We examine the 2008-2016 gamma-ray and optical light curves of a number of bright Fermi blazars. In a fraction of them, the periodograms show possible evidence of quasi-periodicities related in the two bands. This coincidence strengthens their physical meaning. Comparing with results from the periodicity search of quasars, the presence of quasi-periodicities in blazars suggests that the basic condition for its observability is related to the relativistic jet in the observer direction, but the overall picture remains uncertain., 4 pages, 3 figures, in press, New Frontiers in Black Hole Astrophysics. Proceedings IAU Symposium No 324, 2017. Andreja Gomboc and Carole Mundell, eds

The availability of about a decade of uninterrupted sky monitoring by the Fermi satellite has made possible to study long-term quasi-periodicities for high-energy sources. It is therefore not a surprise that for several blazars in the recent literature claims for such periodicities, with various level of confidence, have been reported. The confirmation of these findings could be of tremendous importance for the physical description of this category of sources and have consequences for the gravitational wave background interpretation. In this work we carry out a temporal analysis of the Fermi light curves for several of the sources mentioned in recent literature by means of a homogeneous procedure and find that, globally, no strong cases for blazar year-long quasi-periodicities can be confirmed. The computed power spectral densities are all essentially consistent with being generated by red-noise only. We further discuss the meaning and the limitations of the present analysis., 5 pages, 1 table, 1 figure. MNRAS, in press

Astronomy and astrophysics 619, A159 (2018). doi:10.1051/0004-6361/201833618, Context. PKS 1510–089 is a flat spectrum radio quasar strongly variable in the optical and GeV range. To date, very high-energy (VHE, > 100 GeV) emission has been observed from this source either during long high states of optical and GeV activity or during short flares.Aims. We search for low-state VHE gamma-ray emission from PKS 1510–089. We characterize and model the source in a broadband context, which would provide a baseline over which high states and flares could be better understood.Methods. PKS 1510–089 has been monitored by the MAGIC telescopes since 2012. We use daily binned Fermi-LAT flux measurements of PKS 1510–089 to characterize the GeV emission and select the observation periods of MAGIC during low state of activity. For the selected times we compute the average radio, IR, optical, UV, X-ray, and gamma-ray emission to construct a low-state spectral energy distribution of the source. The broadband emission is modeled within an external Compton scenario with a stationary emission region through which plasma and magnetic fields are flowing. We also perform the emission-model-independent calculations of the maximum absorption in the broad line region (BLR) using two different models.Results. The MAGIC telescopes collected 75 hr of data during times when the Fermi-LAT flux measured above 1 GeV was below 3 × 10$^{−8}$ cm$^{−2}$ s$^{−1}$, which is the threshold adopted for the definition of a low gamma-ray activity state. The data show a strongly significant (9.5σ) VHE gamma-ray emission at the level of (4.27 ± 0.61$_{stat}$) × 10$^{−12}$ cm$^{−2}$ s$^{−1}$ above 150 GeV, a factor of 80 lower than the highest flare observed so far from this object. Despite the lower flux, the spectral shape is consistent with earlier detections in the VHE band. The broadband emission is compatible with the external Compton scenario assuming a large emission region located beyond the BLR. For the first time the gamma-ray data allow us to place a limit on the location of the emission region during a low gamma-ray state of a FSRQ. For the used model of the BLR, the 95% confidence level on the location of the emission region allows us to place it at a distance > 74% of the outer radius of the BLR., Published by EDP Sciences, Les Ulis

Context: PKS 1510–089 is a flat spectrum radio quasar strongly variable in the optical and GeV range. To date, very high-energy (VHE, > 100 GeV) emission has been observed from this source either during long high states of optical and GeV activity or during short flares. Aims: We search for low-state VHE gamma-ray emission from PKS 1510–089. We characterize and model the source in a broadband context, which would provide a baseline over which high states and flares could be better understood. Methods: PKS 1510–089 has been monitored by the MAGIC telescopes since 2012. We use daily binned Fermi-LAT flux measurements of PKS 1510–089 to characterize the GeV emission and select the observation periods of MAGIC during low state of activity. For the selected times we compute the average radio, IR, optical, UV, X-ray, and gamma-ray emission to construct a low-state spectral energy distribution of the source. The broadband emission is modeled within an external Compton scenario with a stationary emission region through which plasma and magnetic fields are flowing. We also perform the emission-model-independent calculations of the maximum absorption in the broad line region (BLR) using two different models. Results: The MAGIC telescopes collected 75 hr of data during times when the Fermi-LAT flux measured above 1 GeV was below 3 × 10−8 cm−2 s−1, which is the threshold adopted for the definition of a low gamma-ray activity state. The data show a strongly significant (9.5σ) VHE gamma-ray emission at the level of (4.27 ± 0.61stat) × 10−12 cm−2 s−1 above 150 GeV, a factor of 80 lower than the highest flare observed so far from this object. Despite the lower flux, the spectral shape is consistent with earlier detections in the VHE band. The broadband emission is compatible with the external Compton scenario assuming a large emission region located beyond the BLR. For the first time the gamma-ray data allow us to place a limit on the location of the emission region during a low gamma-ray state of a FSRQ. For the used model of the BLR, the 95% confidence level on the location of the emission region allows us to place it at a distance > 74% of the outer radius of the BLR.

Objectiu Comparar l’error refractiu amb l’estat emocional i trastorns psicològics com l’ansietat, la depressió i la qualitat de vida dels pacients, tenint en compte la edat, el gènere i la entitat del defecte, mitjançant l’ús de tres qüestionaris validats. Material i mètodes. La mostra del estudi es compon per 64 subjectes (29 homes i 35 dones) de edat compresa entre 18 y 80 anys, dividit en 3 grups: 22 joves, 21 adults i 21 gent gran. En funció de l’equivalent esfèric es consideren 4 grups: “no miops” ((≥ -0,50 D), “baixa miopia” (entre -0,75 D i -3,50 D), “miopia mitja” (entre -3,75 D i -5,75 D), “alta miopia” (≤ - 6,00 D). Per a la finalitat de l’estudi disposem de diferents qüestionaris, cada un relatiu a estats emocionals diferents: STAI (ansietat), CECAD (ansietat i depressió) y CUBRECAVI (qualitat de vida). Resultats. L’error refractiu promig en termes d’equivalent esfèric, considerant únicament l’ull dret, es: -1,00 D ± 2,98 D. El 63,3% dels joves son miops (valor mig de 2,28 D ±3,10 D), mentre que tant en el grup d’adults com en el grup de gent gran, el percentatge de persones amb miopia es inferior (38.1%), així com el valor mig trobat. Considerant els trastorns psicològics, mitjançant tècniques paramètriques i comparacions múltiples, hem trobat diferencies estadísticament significatives amb la ansietat (p < 0,009) i amb els símptomes psicològics (p < 0,003) tenint en compte l’error refractiu, però no amb el gènere. A més a més, hem trobat diferencies en la variable “educació” (p:0.001) tenint en compte l’edat. Mitjançant tècniques no paramètriques s’ha obtingut diferencies estadísticament significatives amb la variable salut (p

A gamma-ray nearly-periodic oscillation was observed from the well-known GeV/TeV BL Lac object PG 1553+113 by the Fermi Large Area Telescope (LAT). The quasi-periodicity in the gamma-ray flux (E>100 MeV and E>1 GeV), reported for the first time in an active galactic nucleus, is significant with a < 1% probability over red-noise fluctuations. The period of the gamma-ray modulation is 2.18 ± 0.08 observed with 3.5 oscillation maxima. It is supported by significant cross-correlated variations observed in radio and optical flux light curves. Interestingly, one of the physical scenarios that can account for such variability pattern is the presence of a supermassive black hole binary in the nucleus of PG 1553+113. The MAGIC telescopes have observed PG 1553+113 at VHE since 2005. An intense multi-wavelength (MWL) campaign started in 2015 aimed at revealing the physical scenarios that can account for such a variability pattern. The campaign will regularly monitor the source activity from radio to VHE (E>100 GeV) gamma rays and will cover the next maximum of activity, expected between the end of 2016 and beginning of 2017. The MWL data collected during this campaign, coupled with the gamma-ray ones form MAGIC, will be the key to determine the nature of the periodicity to disentangle the processes driving the periodic modulation from flaring activity typical in blazar objects.

Blazars are astrophysical sources whose emission is dominated by non-thermal processes, typically interpreted as synchrotron and inverse Compton emission. Although the general picture is rather robust and consistent with observations, many aspects are still unexplored. Polarimetric monitoring can offer a wealth of information about the physical processes in blazars. Models with largely different physical ingredients can often provide almost indistinguishable predictions for the total flux, but usually are characterized by markedly different polarization properties. We explore, with a pilot study, the possibility to derive structural information about the emitting regions of blazars by means of a joint analysis of rapid variability of the total and polarized flux at optical wavelengths. Short timescale (from tens of seconds to a couple of minutes) optical linear polarimetry and photometry for two blazars, BL Lacertae and PKS 1424+240, was carried out with the PAOLO polarimeter at the 3.6m Telescopio Nazionale Galileo. Several hours of almost continuous observations were obtained for both sources. Our intense monitoring allowed us to draw strongly different scenarios for BL Lacertae and PKS 1424+240, with the former characterized by intense variability on time-scales from hours to a few minutes and the latter practically constant in total flux. Essentially the same behavior is observed for the polarized flux and the position angle. The variability time-scales turned out to be as short as a few minutes, although involving only a few percent variation of the flux. The polarization variability time-scale is generally consistent with the total flux variability. Total and polarized flux appear to be essentially uncorrelated. However, even during our relatively short monitoring, different regimes can be singled out. (abridged), A&A, in press, 8 pages, 5 figures, 2 tables

New claims of periodic variability from gamma-ray blazars have been reported, possibly pointing at milli-pc SMBH binary systems. A modulation of ~2 year on 3.5 cycles was recently discovered with Fermi/LAT on the blazar PG1553+113 -- for the first time in gamma-rays with high significance -- and confirmed by optical lightcurves. Other possible gamma-ray periodic variations have been claimed on PKS 2155-304 and PKS 0537 by Sandrinelli et al. (2015, 2016). The interpretation of such periodicity, when confirmed with continuous observations in following years, is not straightforward. Emission from blazars is dominated by non-thermal emission from the jet; different processes in the jet or at its base, may lead to quasi-periodic emission. We used multi-wavelength (MWL) observations on PG1553+113 to investigate if the observed modulation can be explained with geometrical variations in the jet, possibly pointing to jet precession or to an helical pattern. The ongoing MWL monitoring campaign from radio to very-high energy gamma-ray bands, led by the MAGIC collaboration, will follow the maximum expected at the beginning of 2017, and will allow to set tighter constrains on underlying periodic processes.

We analyze the environment of a sample of 20 quasar physical pairs at 0.4

We have considered the Fermi γ-ray light curve of the blazar PKS 0537-441 during a high state extending from 2008 August 10 to 2011 August 27. The periodogram exhibits a peak at T ∼ 280 days, with a significance of ∼99.7%. A peak of similar relevance at \frac{1}{2}T is found in the optical light curves. Considering the entire duration of the Fermi light curve 2008-2015, no significant peak is revealed, while the optical one remains meaningful. Comparing with recent observations of PKS 2155-304 and PG 1553+113 it seems that month-year oscillations can characterize some blazars. Month-scale oscillations can also show up only during phases of enhanced or bursting emission, such as in the case of PKS 0537-441.

We searched for quasi-periodicities on year-like timescales in the light curves of 6 blazars in the optical - near infrared bands and we made a comparison with the high energy emission. We obtained optical/NIR light curves from REM photometry plus archival SMARTS data and we accessed the Fermi light curves for the $\gamma$-ray data. The periodograms often show strong peaks in the optical and gamma-ray bands, which in some cases may be inter-related. The significance of the revealed peaks is then discussed, taking into account that the noise is frequency dependent. Quasi-periodicities on a year-like timescale appear to occur often in blazars. No straightforward model describing these possible periodicities is yet available, but some plausible interpretations for the physical mechanisms causing periodic variabilities of these sources are examined., Comment: 31 pages, 23 figures. Accepted for publication in The Astronomical Journal