422 research outputs found
Safety of 41 flavouring compounds providing a herbal flavour and belonging to different chemical groups for use as feed additives in all animal species (FEFANA asbl)
: Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety of 41 compounds to provide a Herbal flavour and belonging to different chemical groups, when used as sensory additives in feed for all animal species. Fourteen out of the 41 compounds were tested in tolerance studies in chickens for fattening, piglets, cattle for fattening and Atlantic salmon. No adverse effects were observed in the tolerance studies at 10-fold the intended level. The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the 14 tested compounds were safe for these species at the proposed use level and conclusions were extrapolated to all animal species. For the remaining 27 compounds, read-across from structurally similar compounds tested in tolerance trials and belonging to the same chemical group was applied. The FEEDAP Panel concluded that these 27 compounds were safe for all animal species at the proposed use level. No safety concern would arise for the consumer and the environment from the use of the 41 compounds up to the maximum proposed use level in feed
Context-dependent cheating: experimental evidence from 16 countries
Policy makers use several international indices that characterize countries according to the quality of their
institutions. However, no effort has been made to study how the honesty of citizens varies across countries. This paper explores the honesty among citizens across sixteen countries with 1440 participants. We employ a very simple task where participants face a trade-off between the joy of eating a fine chocolate and the disutility of having a threatened self-concept because of lying. Despite the incentives to cheat, we find that individuals are mostly honest. Further, international indices that are indicative of institutional honesty are completely uncorrelated with citizens' honesty for our sample countries
Planck intermediate results. VIII. Filaments between interacting clusters
About half of the baryons of the Universe are expected to be in the form of
filaments of hot and low density intergalactic medium. Most of these baryons
remain undetected even by the most advanced X-ray observatories which are
limited in sensitivity to the diffuse low density medium. The Planck satellite
has provided hundreds of detections of the hot gas in clusters of galaxies via
the thermal Sunyaev-Zel'dovich (tSZ) effect and is an ideal instrument for
studying extended low density media through the tSZ effect. In this paper we
use the Planck data to search for signatures of a fraction of these missing
baryons between pairs of galaxy clusters. Cluster pairs are good candidates for
searching for the hotter and denser phase of the intergalactic medium (which is
more easily observed through the SZ effect). Using an X-ray catalogue of
clusters and the Planck data, we select physical pairs of clusters as
candidates. Using the Planck data we construct a local map of the tSZ effect
centered on each pair of galaxy clusters. ROSAT data is used to construct X-ray
maps of these pairs. After having modelled and subtracted the tSZ effect and
X-ray emission for each cluster in the pair we study the residuals on both the
SZ and X-ray maps. For the merging cluster pair A399-A401 we observe a
significant tSZ effect signal in the intercluster region beyond the virial
radii of the clusters. A joint X-ray SZ analysis allows us to constrain the
temperature and density of this intercluster medium. We obtain a temperature of
kT = 7.1 +- 0.9, keV (consistent with previous estimates) and a baryon density
of (3.7 +- 0.2)x10^-4, cm^-3. The Planck satellite mission has provided the
first SZ detection of the hot and diffuse intercluster gas.Comment: Accepted by A&
Performance and first measurements of the MAGIC stellar intensity interferometer
In recent years, a new generation of optical intensity interferometers has emerged, leveraging the existing infrastructure of Imaging Atmospheric Cherenkov Telescopes (IACTs). The MAGIC telescopes host the MAGIC-SII system (Stellar Intensity Interferometer), implemented to investigate the feasibility and potential of this technique on IACTs. After the first successful measurements in 2019, the system was upgraded and now features a real-time, dead-time-free, 4-channel, GPU-based correlator. These hardware modifications allow seamless transitions between MAGICâs standard very-high-energy gamma-ray observations and optical interferometry measurements within seconds. We establish the feasibility and potential of employing IACTs as competitive optical Intensity Interferometers with minimal hardware adjustments. The measurement of a total of 22 stellar diameters are reported, 9 corresponding to reference stars with previous comparable measurements, and 13 with no prior measurements. A prospective implementation involving telescopes from the forthcoming Cherenkov Telescope Array Observatoryâs Northern hemisphere array, such as the first prototype of its Large-Sized Telescopes, LST-1, is technically viable. This integration would significantly enhance the sensitivity of the current system and broaden the UV-plane coverage. This advancement would enable the system to achieve competitive sensitivity with the current generation of long-baseline optical interferometers over blue wavelengths
A detailed study of the very-high-energy Crab pulsar emission with the LST-1
Context: There are currently three pulsars firmly detected by imaging atmospheric Cherenkov telescopes (IACTs), two of them reaching TeV energies, challenging models of very-high-energy (VHE) emission in pulsars. More precise observations are needed to better characterize pulsar emission at these energies. The LST-1 is the prototype of the Large-Sized Telescope, that will be part of the Cherenkov Telescope Array Observatory (CTAO). Its improved performance over previous IACTs makes it well suited for studying pulsars. Aims: To study the Crab pulsar emission with the LST-1, improving and complementing the results from other telescopes. These observations can also be used to characterize the potential of the LST-1 to study other pulsars and detect new ones. Methods: We analyzed a total of 103 hours of gamma-ray observations of the Crab pulsar conducted with the LST-1 in the period from September 2020 to January 2023. The observations were carried out at zenith angles less than 50 degrees. A new analysis of the Fermi-LAT data was also performed, including 14 years of observations. Results: The Crab pulsar phaseogram, long-term light-curve, and phase-resolved spectra are reconstructed with the LST-1 from 20 GeV to 450 GeV for P1 and up to 700 GeV for P2. The pulsed emission is detected with a significance of 15.2. The two characteristic emission peaks of the Crab pulsar are clearly detected (>10), as well as the so-called bridge emission (5.7). We find that both peaks are well described by power laws, with spectral indices of 3.44 and 3.03 respectively. The joint analysis of Fermi-LAT and LST-1 data shows a good agreement between both instruments in the overlapping energy range. The detailed results obtained in the first observations of the Crab pulsar with LST-1 show the potential that CTAO will have to study this type of sources
Constraints on models of the Higgs boson with exotic spin and parity using decays to bottom-antibottom quarks in the full CDF data set
A search for particles with the same mass and couplings as those of the standard model Higgs boson but different spin and parity quantum numbers is presented. We test two specific alternative Higgs boson hypotheses: a pseudoscalar Higgs boson with spin-parity JP=0- and a gravitonlike Higgs boson with JP=2+, assuming for both a mass of 125GeV/c2. We search for these exotic states produced in association with a vector boson and decaying into a bottom-antibottom quark pair. The vector boson is reconstructed through its decay into an electron or muon pair, or an electron or muon and a neutrino, or it is inferred from an imbalance in total transverse momentum. We use expected kinematic differences between events containing exotic Higgs bosons and those containing standard model Higgs bosons. The data were collected by the CDF experiment at the Tevatron proton-antiproton collider, operating at a center-of-mass energy of s=1.96TeV, and correspond to an integrated luminosity of 9.45fb-1. We exclude deviations from the predictions of the standard model with a Higgs boson of mass 125GeV/c2 at the level of 5 standard deviations, assuming signal strengths for exotic boson production equal to the prediction for the standard model Higgs boson, and set upper limits of approximately 30% relative to the standard model rate on the possible rate of production of each exotic state
Interplay between Structure and Dynamics in Chitosan Films Investigated with Solid-State NMR, Dynamic Mechanical Analysis, and X-ray Diffraction
Modern solid-state NMR techniques, combined with X-ray diffraction, revealed the molecular origin of the difference in mechanical properties of self-associated chitosan films. Films cast from acidic aqueous solutions were compared before and after neutralization, and the role of the counterion (acetate vs Clâ») was investigated. There is a competition between local structure and long-range order. Hydrogen bonding gives good mechanical strength to neutralized films, which lack long-range organization. The long-range structure is better defined in films cast from acidic solutions in which strong electrostatic interactions cause rotational distortion around the chitosan chains. Plasticization by acetate counterions enhances long-range molecular organization and film flexibility. In contrast, Clâ» counterions act as a defect and impair the long-range organization by immobilizing hydration water. Molecular motion and proton exchange are restricted, resulting in brittle films despite the high moisture content
A hot mini-Neptune and a temperate, highly eccentric sub-Saturn around the bright K-dwarf TOI-2134
Funding: ACC and TGW acknowledge support from STFC consolidated grant numbers ST/R000824/1 and ST/V000861/1, and UKSA grant number ST/R003203/1. RDH is funded by the UK Science and Technology Facilities Council (STFC)âs Ernest Rutherford Fellowship (grant no. ST/V004735/1). SD is funded by the UK Science and Technology Facilities Council (grant no. ST/V004735/1). BSL is funded by a UK Science and Technology Facilities Council (STFC) studentship (ST/V506679/1). This project has received funding from the European Research Council (ERC) under the European Unionâs Horizon 2020 research and innovation programme (grant agreement SCORE no. 851555).We present the characterisation of an inner mini-Neptune in a 9.2292005±0.0000063 day orbit and an outer mono-transiting sub-Saturn planet in a 95.50+0.36-0.25 day orbit around the moderately active, bright (mv = 8.9 mag) K5V star TOI-2134. Based on our analysis of five sectors of TESS data, we determine the radii of TOI-2134b and c to be 2.69±0.16 Râ for the inner planet and 7.27±0.42 Râ for the outer one. We acquired 111 radial-velocity spectra with HARPS-N and 108 radial-velocity spectra with SOPHIE. After careful periodogram analysis, we derive masses for both planets via Gaussian Process regression: 9.13+0.78-0.76 Mâ for TOI-2134b and 41.89+7.69-7.83 Mâ for TOI-2134c. We analysed the photometric and radial-velocity data first separately, then jointly. The inner planet is a mini-Neptune with density consistent with either a water-world or a rocky core planet with a low-mass H/He envelope. The outer planet has a bulk density similar to Saturnâs. The outer planet is derived to have a significant eccentricity of 0.67+0.05-0.06 from a combination of photometry and RVs. We compute the irradiation of TOI-2134c as 1.45±0.10 times the bolometric flux received by Earth, positioning it for part of its orbit in the habitable zone of its system. We recommend further RV observations to fully constrain the orbit of TOI-2134c. With an expected Rossiter-McLaughlin (RM) effect amplitude of 7.2±1.3 m-1, we recommend TOI-2134c for follow-up RM analysis to study the spin-orbit architecture of the system. We calculate the Transmission Spectroscopy Metric, and both planets are suitable for bright-mode NIRCam atmospheric characterisation.Publisher PDFPeer reviewe
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