264 research outputs found
Identifying Promising Themes for Adolescent Vaping Warnings: A National Experiment
Introduction: Adolescent vaping remains a problem in the United States, yet little is known about what health warning themes most discourage vaping among adolescents. We sought to identify the most compelling themes for vaping warnings for US adolescents. Methods: Participants were a national probability sample of 623 US adolescents aged 13-17 years, recruited in the summer of 2020. Adolescents were randomized to one of the five warning message themes about the potential health effects of vaping: 1. chemical harms, 2. lung harms, 3. Coronavirus Disease 2019 (COVID-19) harms, 4. nicotine addiction, or 5. control (messages about vape litter). The primary outcome was perceived message effectiveness (PME; 3-item scale). Secondary outcomes were negative affect (fear), attention, anticipated social interactions, and message novelty. Results: Adolescents rated the chemical, lung, and COVID-19 harms warning messages higher on PME than nicotine addiction and control (all p <. 05), while nicotine addiction was rated higher than control (p <. 05). The chemical, lung, and COVID-19 harms warning themes also elicited greater negative affect than nicotine addiction and control (all p <. 05). For all other secondary outcomes, the COVID-19 harms warning message theme was rated higher than nicotine addiction and control (all p <. 05). Conclusion: Adolescents perceived warning message themes about lung, chemical and COVID-19 health effects of vaping as more effective than nicotine addiction. To discourage vaping, the FDA and others should communicate to youth about the health effects of vaping beyond nicotine addiction. Implications: Adolescents rated warning message themes about the lung, chemical, and COVID-19 health effects of vaping as more effective than nicotine addiction, while nicotine addiction was rated as more effective than control themes about vaping litter. To discourage vaping among adolescents, health messaging should expand message themes to communicate about a broader set of health effects of vaping beyond nicotine addiction
Sensations of skin infestation linked to abnormal frontolimbic brain reactivity and differences in self-representation
Some patients experience skin sensations of infestation and contamination that are elusive to proximate dermatological explanation. We undertook a functional magnetic resonance imaging study of the brain to demonstrate, for the first time, that central processing of infestation-relevant stimuli is altered in patients with such abnormal skin sensations. We show differences in neural activity within amygdala, insula, middle temporal lobe and frontal cortices. Patients also demonstrated altered measures of self-representation, with poorer sensitivity to internal bodily (interoceptive) signals and greater susceptibility to take on an illusion of body ownership: the rubber hand illusion. Together, these findings highlight a potential model for the maintenance of abnormal skin sensations, encompassing heightened threat processing within amygdala, increased salience of skin representations within insula and compromised prefrontal capacity for self-regulation and appraisal
Probabilistic non-linear registration with spatially adaptive regularisation
This paper introduces a novel method for inferring spatially varying regularisation in non-linear registration. This is achieved through full Bayesian inference on a probabilistic registration model, where the prior on the transformation parameters is parameterised as a weighted mixture of spatially localised components. Such an approach has the advantage of allowing the registration to be more flexibly driven by the data than a traditional globally defined regularisation penalty, such as bending energy. The proposed method adaptively determines the influence of the prior in a local region. The strength of the prior may be reduced in areas where the data better support deformations, or can enforce a stronger constraint in less informative areas. Consequently, the use of such a spatially adaptive prior may reduce unwanted impacts of regularisation on the inferred transformation. This is especially important for applications where the deformation field itself is of interest, such as tensor based morphometry. The proposed approach is demonstrated using synthetic images, and with application to tensor based morphometry analysis of subjects with Alzheimer’s disease and healthy controls. The results indicate that using the proposed spatially adaptive prior leads to sparser deformations, which provide better localisation of regional volume change. Additionally, the proposed regularisation model leads to more data driven and localised maps of registration uncertainty. This paper also demonstrates for the first time the use of Bayesian model comparison for selecting different types of regularisation
Quantum walks: a comprehensive review
Quantum walks, the quantum mechanical counterpart of classical random walks,
is an advanced tool for building quantum algorithms that has been recently
shown to constitute a universal model of quantum computation. Quantum walks is
now a solid field of research of quantum computation full of exciting open
problems for physicists, computer scientists, mathematicians and engineers.
In this paper we review theoretical advances on the foundations of both
discrete- and continuous-time quantum walks, together with the role that
randomness plays in quantum walks, the connections between the mathematical
models of coined discrete quantum walks and continuous quantum walks, the
quantumness of quantum walks, a summary of papers published on discrete quantum
walks and entanglement as well as a succinct review of experimental proposals
and realizations of discrete-time quantum walks. Furthermore, we have reviewed
several algorithms based on both discrete- and continuous-time quantum walks as
well as a most important result: the computational universality of both
continuous- and discrete- time quantum walks.Comment: Paper accepted for publication in Quantum Information Processing
Journa
Observation of hard scattering in photoproduction events with a large rapidity gap at HERA
Events with a large rapidity gap and total transverse energy greater than 5
GeV have been observed in quasi-real photoproduction at HERA with the ZEUS
detector. The distribution of these events as a function of the
centre of mass energy is consistent with diffractive scattering. For total
transverse energies above 12 GeV, the hadronic final states show predominantly
a two-jet structure with each jet having a transverse energy greater than 4
GeV. For the two-jet events, little energy flow is found outside the jets. This
observation is consistent with the hard scattering of a quasi-real photon with
a colourless object in the proton.Comment: 19 pages, latex, 4 figures appended as uuencoded fil
D* Production in Deep Inelastic Scattering at HERA
This paper presents measurements of D^{*\pm} production in deep inelastic
scattering from collisions between 27.5 GeV positrons and 820 GeV protons. The
data have been taken with the ZEUS detector at HERA. The decay channel
(+ c.c.) has been used in the study. The
cross section for inclusive D^{*\pm} production with
and is 5.3 \pms 1.0 \pms 0.8 nb in the kinematic region
{ GeV and }. Differential cross
sections as functions of p_T(D^{*\pm}), and are
compared with next-to-leading order QCD calculations based on the photon-gluon
fusion production mechanism. After an extrapolation of the cross section to the
full kinematic region in p_T(D^{*\pm}) and (D^{*\pm}), the charm
contribution to the proton structure function is
determined for Bjorken between 2 10 and 5 10.Comment: 17 pages including 4 figure
Observation of Scaling Violations in Scaled Momentum Distributions at HERA
Charged particle production has been measured in deep inelastic scattering
(DIS) events over a large range of and using the ZEUS detector. The
evolution of the scaled momentum, , with in the range 10 to 1280
, has been investigated in the current fragmentation region of the Breit
frame. The results show clear evidence, in a single experiment, for scaling
violations in scaled momenta as a function of .Comment: 21 pages including 4 figures, to be published in Physics Letters B.
Two references adde
Metazoan parasite of lambari Astyanax altiparanae, collected from the Peixe river, São Paulo, southeast of Brazil
Structure of the parasite infracommunity of Sciades proops from the Japaratuba River Estuary, Sergipe, Brazil
Dissodactylus crinitichelis Moreira, 1901 and Leodia sexiesperforata (Leske, 1778): first record of this symbiosis in Brazil
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