415 research outputs found
Editorial : The psychology of fake news on social media, who falls for it, who shares it, why, and can we help users detect it?
The proliferation of fake news on social media has become a major societal concern which has been shown to impact elections, referenda, and effective public health messaging (Lewandowsky et al., 2017). To combat this, there is now a growing body of research that focuses on the role of psychological and behavioural science in understanding and mitigating the spread of misinformation (Rapp & Salovich, 2018;Van Bavel et al., 2020). For example, research on belief revision has reported a 'continued influence effect' (CIE) where misinformation lingers in the mind of a person despite being categorically refuted (e.g., Ecker et al., 2010;Desai et al., 2020), simulations have attempted to replicate the seepage of misinformation in social networks (Lewandowsky et al., 2019), and inoculation theorists are building training tools to understand and enhance psychological resistance against misinformation. Such attempts have been conducted in the context of COVID-19 (Basol et al., 2021), political disinformation (Roozenbeek & van der Linden, 2020), and climate change (Maertens et al., 2020). While it is clear that important advances have been made in our understanding of the critical psychological functions that underpin how individuals seek out, process, and share misinformation -there is still much to do. Therefore, in this special topic, we are delighted to introduce six new papers which present novel, interesting, and engaging contributions to our understanding of the fake news phenomenon
Nuclear organisation and replication timing are coupled through RIF1-PP1 interaction
Three-dimensional genome organisation and replication timing are known to be correlated, however, it remains unknown whether nuclear architecture overall plays an instructive role in the replication-timing programme and, if so, how. Here we demonstrate that RIF1 is a molecular hub that co-regulates both processes. Both nuclear organisation and replication timing depend upon the interaction between RIF1 and PP1. However, whereas nuclear architecture requires the full complement of RIF1 and its interaction with PP1, replication timing is not sensitive to RIF1 dosage. The role of RIF1 in replication timing also extends beyond its interaction with PP1. Availing of this separation-of-function approach, we have therefore identified in RIF1 dual function the molecular bases of the co-dependency of the replication-timing programme and nuclear architecture
Photon Physics in Heavy Ion Collisions at the LHC
Various pion and photon production mechanisms in high-energy nuclear
collisions at RHIC and LHC are discussed. Comparison with RHIC data is done
whenever possible. The prospect of using electromagnetic probes to characterize
quark-gluon plasma formation is assessed.Comment: Writeup of the working group "Photon Physics" for the CERN Yellow
Report on "Hard Probes in Heavy Ion Collisions at the LHC", 134 pages. One
figure added in chapter 5 (comparison with PHENIX data). Some figures and
correponding text corrected in chapter 6 (off-chemical equilibrium thermal
photon rates). Some figures modified in chapter 7 (off-chemical equilibrium
photon rates) and comparison with PHENIX data adde
Numerical Portrait of a Relativistic BCS Gapped Superfluid
We present results of numerical simulations of the 3+1 dimensional Nambu -
Jona-Lasinio (NJL) model with a non-zero baryon density enforced via the
introduction of a chemical potential mu not equal to 0. The triviality of the
model with a number of dimensions d>=4 is dealt with by fitting low energy
constants, calculated analytically in the large number of colors (Hartree)
limit, to phenomenological values. Non-perturbative measurements of local order
parameters for superfluidity and their related susceptibilities show that, in
contrast to the 2+1 dimensional model, the ground-state at high chemical
potential and low temperature is that of a traditional BCS superfluid. This
conclusion is supported by the direct observation of a gap in the dispersion
relation for 0.5<=(mu a)<=0.85, which at (mu a)=0.8 is found to be roughly 15%
the size of the vacuum fermion mass. We also present results of an initial
investigation of the stability of the BCS phase against thermal fluctuations.
Finally, we discuss the effect of splitting the Fermi surfaces of the pairing
partners by the introduction of a non-zero isospin chemical potential.Comment: 41 pages, 19 figures, uses axodraw.sty, v2: minor typographical
correction
NA60 results on thermal dimuons
The NA60 experiment at the CERN SPS has measured muon pairs with
unprecedented precision in 158A GeV In-In collisions. A strong excess of pairs
above the known sources is observed in the whole mass region 0.2<M<2.6 GeV. The
mass spectrum for M<1 GeV is consistent with a dominant contribution from
pi+pi- -> rho -> mu+mu- annihilation. The associated rho spectral function
shows a strong broadening, but essentially no shift in mass. For M>1 GeV, the
excess is found to be prompt, not due to enhanced charm production, with
pronounced differences to Drell-Yan pairs. The slope parameter Teff associated
with the transverse momentum spectra rises with mass up to the rho, followed by
a sudden decline above. The rise for M<1 GeV is consistent with radial flow of
a hadronic emission source. The seeming absence of significant flow for M>1 GeV
and its relation to parton-hadron duality is discussed in detail, suggesting a
dominantly partonic emission source in this region. A comparison of the data to
the present status of theoretical modeling is also contained. The accumulated
empirical evidence, including also a Planck-like shape of the mass spectra at
low pT and the lack of polarization, is consistent with a global interpretation
of the excess dimuons as thermal radiation. We conclude with first results on
omega in-medium effects.Comment: 10 pages, 12 figures, submitted to Eur. Phys. J.
Evidence for radial flow of thermal dileptons in high-energy nuclear collisions
The NA60 experiment at the CERN SPS has studied low-mass dimuon production in
158 AGeV In-In collisions. An excess of pairs above the known meson decays has
been reported before. We now present precision results on the associated
transverse momentum spectra. The slope parameter Teff extracted from the
spectra rises with dimuon mass up to the rho, followed by a sudden decline
above. While the initial rise is consistent with the expectations for radial
flow of a hadronic decay source, the decline signals a transition to an
emission source with much smaller flow. This may well represent the first
direct evidence for thermal radiation of partonic origin in nuclear collisions.Comment: Accepted for publication in Physical Review Letter
Study of the electromagnetic transition form-factors in \eta -> \mu^+\mu^-\gamma and \omega -> \mu^+\mu^-\pi^0 decays with NA60
The NA60 experiment at the CERN SPS has studied low-mass muon pairs in 158A
GeV In-In collisions. The mass and pT spectra associated with peripheral
collisions can quantitatively be described by the known neutral meson decays.
The high data quality has allowed to remeasure the electromagnetic transition
form factors of the Dalitz decays \eta -> \mu^+\mu^-\gamma and \omega ->
\mu^+\mu^-\pi^0. Using the usual pole approximation F =
(1-M_{\mu\mu}^{2}/\Lambda^{2})^{-1} for the form factors, we find \Lambda^{-2}
(in GeV^{-2}) to be 1.95+-0.17(stat.)+-0.05(syst.) for the \eta and
2.24+-0.06(stat.)+-0.02(syst.) for the \omega. While the values agree with
previous results from the Lepton-G experiment, the errors are greatly improved,
confirming now on the level of 10\sigma the strong enhancement of the \omega
form factor beyond the expectation from vector meson dominance. An improved
value of the branching ratio BR(\omega -> \mu^+\mu^-\pi^0) =
[1.73+-0.25(stat.)+-0.14(syst.)]*10^{-4} has been obtained as a byproduct.Comment: Submitted to Phys. Lett.
RHIC physics overview
The results from data taken during the last several years at the Relativistic
Heavy-Ion Collider (RHIC) will be reviewed in the paper. Several selected
topics that further our understanding of constituent quark scaling, jet
quenching and color screening effect of heavy quarkonia in the hot dense medium
will be presented. Detector upgrades will further probe the properties of Quark
Gluon Plasma. Future measurements with upgraded detectors will be presented.
The discovery perspectives from future measurements will also be discussed.Comment: 9 pages, 4 figures, invited review article, published by Frontier of
Physics in Chin
The impact of itch symptoms in psoriasis: results from physician interviews and patient focus groups
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