98 research outputs found
High power ultrasound treatments of red young wines: effect on anthocyanins and phenolic stability indices
6openInternationalItalian coauthor/editorPolyphenols, especially anthocyanins, play an important role on red wine sensory qualities and their evolution during storage. High Power Ultrasound (HPU) has been recognized as one of the most promising technologies which can be applied in winemaking processes for several purposes, and it is recently officially approved for crushed grapes treatments. The effect of ultrasound amplitude (41 and 81%) and treatment time (1, 3, and 5 min) has been studied on anthocyanins, flavan-3-ols, tannins, polymerized pigments, HCl index, and the color intensity of two finished red young wines. Anthocyanins and phenols compounds were not degraded with an increase in amplitude and sonication time, and the chromatic properties of the selected wines were preserved. Amplitude and ultrasound time were also evaluated considering their effect on evolution of anthocyanin content and phenolic stability indices during the first thirty days of storage. The higher level of amplitude (81%) induced a higher percentage decrease in tannins, 15% and 40% after 15 and 30 days of storage, respectively, compared to untreated wine which did not show a significant change during storage. HPU shows a possible chemical effect on the evolution of some analytical indices during bottling maturation, but their effectiveness could be strictly linked with the initial phenolic profile and ratios between polyphenol classesopenCelotti, E.; Stante, S.; Ferraretto, P.; Roman, T.; Nicolini, G.; Natolino, A.Celotti, E.; Stante, S.; Ferraretto, P.; Roman, T.; Nicolini, G.; Natolino, A
Inter-comparison of Radio-Loudness Criteria for Type 1 AGNs in the XMM-COSMOS Survey
Limited studies have been performed on the radio-loud fraction in X-ray
selected type 1 AGN samples. The consistency between various radio-loudness
definitions also needs to be checked. We measure the radio-loudness of the 407
type 1 AGNs in the XMM-COSMOS quasar sample using nine criteria from the
literature (six defined in the rest-frame and three defined in the observed
frame): , ,
, ,
, ,
(observed frame),
(observed frame), and (observed frame). Using any single criterion
defined in the rest-frame, we find a low radio-loud fraction of
in the XMM-COSMOS type 1 AGN sample, except for . Requiring that any
two criteria agree reduces the radio-loud fraction to for about
3/4 of the cases. The low radio-loud fraction cannot be simply explained by the
contribution of the host galaxy luminosity and reddening. The
gives the smallest radio-loud fraction. Two
of the three radio-loud fractions from the criteria defined in the observed
frame without k-correction ( and ) are much larger than
the radio-loud fractions from other criteria.Comment: 12 pages, 7 figures, MNRAS submitte
Trend of estimated glomerular flitration rate in a large cohort of HIV mother-to -child infected patients, an observational multicenter study from 2010 to 2018
Background: People vertically infected with HIV (PVI-HIV) are a special population, due to exposition since birth
to HIV and antiretroviral therapy (ART). Among ART, Tenofovir disoproxil fumarate (TDF) was widely used in
recent years, but there are few data on safety in these patients; in particular, data about estimated glomerular
filtration rate (eGFR) trend in this population. Aim of our study is to evaluate eGFR trend in a multicentre cohort
of PVI-HIV exposed to TDF
Jet-disc coupling through a common energy reservoir in the black hole XTE J1118+480
We interpret the rapid correlated UV/optical/ X-ray variability of XTE
J1118+480 as a signature of the coupling between the X-ray corona and a jet
emitting synchrotron radiation in the optical band. We propose a scenario in
which the jet and the X-ray corona are fed by the same energy reservoir where
large amounts of accretion power are stored before being channelled into either
the jet or the high energy radiation. This time dependent model reproduces the
main features of the rapid multi-wavelength variability of XTE J1118+480.
Assuming that the energy is stored in the form of magnetic field, we find that
the required values of the model parameters are compatible with both a patchy
corona atop a cold accretion disc and a hot thick inner disc geometry. The
range of variability timescales for the X-ray emitting plasma are consistent
with the dynamical times of an accretion flow between 10 and 100 Schwarzschild
radii. On the other hand, the derived range of timescales associated with the
dissipation in the jet extends to timescales more than 10 times larger,
confirming the suggestion that the generation of a powerful outflow requires
large scale coherent poloidal field structures. A strong requirement of the
model is that the total jet power should be at least a few times larger than
the observed X-ray luminosity. This would be consistent with the overall low
radiative efficiency of the source. We present independent arguments showing
that the jet probably dominates the energetic output of all accreting black
holes in the low-hard state.Comment: 14 pages, 2 figures, to appear in MNRA
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Fertigation affects photosynthesis, modulation of secondary metabolism and sensory profiles of Vitis vinifera cv. “Schioppettino” withered grapes and wines
Nowadays a balance in plant production is required, especially in terms of nutrition, yield and for an optimal aroma and sensory profile of resulted wines. In this research, we compared two different methods of plant nutrition: one-single application (single-fertilization-SF) and two applications with the same amount adopting the fertigation (split fertigation-SpF), including a control not-treated, in a specific Italian region where grapevine Schiopettino cv. is being cultivated and this practice was not investigated yet. SpF promoted the photosynthesis parameters compared to a SF and to the non-treated vines (NTC). On these basis, the biological and physiological activity of the whole plant was enhanced. SpF treatment tendentially and significantly improved the qualitative, productive, physiological, and oenological parameters of “Schioppettino” wine
A bright megaelectronvolt emission line in -ray burst GRB 221009A
The highly variable and energetic pulsed emission of a long gamma-ray burst
(GRB) is thought to originate from local, rapid dissipation of kinetic or
magnetic energy within an ultra-relativistic jet launched by a newborn compact
object, formed during the collapse of a massive star. The spectra of GRB pulses
are best modelled by power-law segments, indicating the dominance of
non-thermal radiation processes. Spectral lines in the X-ray and soft
-ray regime for the afterglow have been searched for intensively, but
never confirmed. No line features ever been identified in the high energy
prompt emission. Here we report the discovery of a highly significant () narrow emission feature at around MeV in the brightest ever GRB
221009A. By modelling its profile with a Gaussian, we find a roughly constant
width MeV and temporal evolution both in energy ( MeV
to MeV) and luminosity ( erg/s to erg/s) over 80 seconds. We interpret this feature as a blue-shifted
annihilation line of relatively cold ()
electron-positron pairs, which could have formed within the jet region where
the brightest pulses of the GRB were produced. A detailed understanding of the
conditions that can give rise to such a feature could shed light on the so far
poorly understood GRB jet properties and energy dissipation mechanism.Comment: Submitte
Novel Textbook Outcomes following emergency laparotomy:Delphi exercise
Background: Textbook outcomes are composite outcome measures that reflect the ideal overall experience for patients. There are many of these in the elective surgery literature but no textbook outcomes have been proposed for patients following emergency laparotomy. The aim was to achieve international consensus amongst experts and patients for the best Textbook Outcomes for non-trauma and trauma emergency laparotomy. Methods: A modified Delphi exercise was undertaken with three planned rounds to achieve consensus regarding the best Textbook Outcomes based on the category, number and importance (Likert scale of 1–5) of individual outcome measures. There were separate questions for non-trauma and trauma. A patient engagement exercise was undertaken after round 2 to inform the final round. Results: A total of 337 participants from 53 countries participated in all three rounds of the exercise. The final Textbook Outcomes were divided into ‘early’ and ‘longer-term’. For non-trauma patients the proposed early Textbook Outcome was ‘Discharged from hospital without serious postoperative complications (Clavien–Dindo ≥ grade III; including intra-abdominal sepsis, organ failure, unplanned re-operation or death). For trauma patients it was ‘Discharged from hospital without unexpected transfusion after haemostasis, and no serious postoperative complications (adapted Clavien–Dindo for trauma ≥ grade III; including intra-abdominal sepsis, organ failure, unplanned re-operation on or death)’. The longer-term Textbook Outcome for both non-trauma and trauma was ‘Achieved the early Textbook Outcome, and restoration of baseline quality of life at 1 year’. Conclusion: Early and longer-term Textbook Outcomes have been agreed by an international consensus of experts for non-trauma and trauma emergency laparotomy. These now require clinical validation with patient data.</p
A mega-electron volt emission line in the spectrum of a gamma-ray burst
A long gamma–ray burst (GRB) is observed when the collapse of a massive star produces an ultrarelativistic outflow pointed toward Earth. Gamma-ray spectra of long GRBs are smooth, typically modeled by joint power-law segments describing a continuum, with no detected spectral lines. We report a significant (>6σ) narrow emission feature at ~10 mega–electron volts (MeV) in the spectrum of the bright GRB 221009A. Over 80 seconds, it evolves in energy (~12 to ~6 MeV) and in luminosity (~1.1 to <0.43 × 1050 erg second−1) but has a constant width of ~1 MeV. We interpret this feature as a blueshifted spectral line produced by the annihilation of electron-positron pairs, potentially in the same location responsible for emitting the brightest GRB pulses.M.E.R. acknowledges support from the research program Athena with project number 184.034.002, which is financed by the Dutch Research Council (NWO). O.S.S. acknowledges funding by the European Union-Next Generation EU, PRIN 2022 RFF M4C21.1 (202298J7KT- PEACE). S.A. is supported by the H2020 ERC Consolidator Grant “MAGNESIA” (grant no. 817661; principal investigator: Rea) and National Spanish grant PGC2018-095512-BI00. A.J.L. and D.B.M. are supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant no. 725246). D.B.M. thanks the Cosmic Dawn Center, supported by the Danish National Research Foundation (grant DNRF140), for kind hospitality. G.O. and M.B. acknowledge financial support from the European Union’s Horizon 2020 Programme under the AHEAD2020 project (grant no. 871158). B.B. and M.B. acknowledge financial support from the Italian Ministry of University and Research (MUR) for the PRIN grant METE under contract no. 2020KB33TPPeer reviewe
A quasar-galaxy mixing diagram: quasar spectral energy distribution shapes in the optical to near-infrared
We define a quasar-galaxy mixing diagram using the slopes of their spectral energy distributions (SEDs) from 1 \u3bcm to 3000 \uc5 and from 1 to 3 \u3bcm in the rest frame. The mixing diagram can easily distinguish among quasar-dominated, galaxy-dominated and reddening-dominated SED shapes. By studying the position of the 413 XMM-selected type 1 AGN in the wide-field `Cosmic Evolution Survey' in the mixing diagram, we find that a combination of the Elvis et al. mean quasar SED with various contributions from galaxy emission and some dust reddening is remarkably effective in describing the SED shape from 0.3 to 3 \u3bcm for large ranges of redshift, luminosity, black hole mass and Eddington ratio of type 1 AGN. In particular, the location in the mixing diagram of the highest luminosity AGN is very close (within 1\u3c3) to that of the Elvis et al. SED template. The mixing diagram can also be used to estimate the host galaxy fraction and reddening in quasar. We also show examples of some outliers which might be AGN in different evolutionary stages compared to the majority of AGN in the quasar-host galaxy co-evolution cycle
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