Simulation of ion behavior in an open three-dimensional Paul trap using a power series method

Simulations of the dynamics of ions trapped in a Paul trap with terms in the potential up to the order 10 have been carried out. The power series method is used to solve numerically the equations of motion of the ions. The stability diagram has been studied and the buffer gas cooling has been implemented by a Monte Carlo method. The dipole excitation was also included. The method has been applied to an existing trap and it has shown good agreement with the experimental results and previous simulations using other methods

Misinformation on Misinformation: Conceptual and Methodological Challenges

Copyright © 2021 The Author(s). Alarmist narratives about online misinformation continue to gain traction despite evidence that its prevalence and impact are overstated. Drawing on research questioning the use of big data in social science and reception studies, we identify six misconceptions about misinformation and examine the conceptual and methodological challenges they raise. The first three misconceptions concern the prevalence and circulation of misinformation. First, the internet is not rife with misinformation or news, but with memes and entertaining content. Second, scientists focus on social media because it is methodologically convenient, but misinformation is not just a social media problem. Third, falsehoods do not spread faster than the truth; how we define (mis)information influences our results and their practical implications. The second three misconceptions concern the impact and the reception of misinformation. First, people do not believe everything they see on the internet: sheer volume of engagement should not be conflated with belief. Second, the influence of misinformation on people’s behavior is overblown since it often ‘preaches to the choir’. Third, people are more likely to be uninformed than misinformed; surveys overestimate misperceptions and say little about the causal influence of misinformation. To appropriately understand and fight misinformation, future research needs to address these challenges

Towards psychological herd immunity: Cross-cultural evidence for two prebunking interventions against COVID-19 misinformation

Funder: Cabinet Office, Government of the United KingdomMisinformation about the novel coronavirus (COVID-19) is a pressing societal challenge. Across two studies, one preregistered ( n1 = 1771 and n2 = 1777), we assess the efficacy of two ‘prebunking’ interventions aimed at improving people’s ability to spot manipulation techniques commonly used in COVID-19 misinformation across three different languages (English, French and German). We find that Go Viral!, a novel five-minute browser game, (a) increases the perceived manipulativeness of misinformation about COVID-19, (b) improves people’s attitudinal certainty (confidence) in their ability to spot misinformation and (c) reduces self-reported willingness to share misinformation with others. The first two effects remain significant for at least one week after gameplay. We also find that reading real-world infographics from UNESCO improves people’s ability and confidence in spotting COVID-19 misinformation (albeit with descriptively smaller effect sizes than the game). Limitations and implications for fake news interventions are discussed.</jats:p

On inelastic hydrogen atom collisions in stellar atmospheres

The influence of inelastic hydrogen atom collisions on non-LTE spectral line formation has been, and remains to be, a significant source of uncertainty for stellar abundance analyses, due to the difficulty in obtaining accurate data for low-energy atomic collisions either experimentally or theoretically. For lack of a better alternative, the classical "Drawin formula" is often used. Over recent decades, our understanding of these collisions has improved markedly, predominantly through a number of detailed quantum mechanical calculations. In this paper, the Drawin formula is compared with the quantum mechanical calculations both in terms of the underlying physics and the resulting rate coefficients. It is shown that the Drawin formula does not contain the essential physics behind direct excitation by H atom collisions, the important physical mechanism being quantum mechanical in character. Quantitatively, the Drawin formula compares poorly with the results of the available quantum mechanical calculations, usually significantly overestimating the collision rates by amounts that vary markedly between transitions.Comment: 9 pages, 6 figures, accepted for A&

A multiple primer pairs polymerase chain reaction for the detection of human genital papillomavirus types.

International audienceWe describe a polymerase chain reaction (PCR) based on the simultaneous detection of multiple strains of papillomavirus in a single reaction tube. This PCR method was specific and sensitive. We have validated this multiplex procedure on a collection of typed cervical biopsies specimens, and applied it to the detection of viruses in some clinical samples

Ab initio calculations of electronic structure of the BaCs molecule: adiabatic potential energy curves, spectroscopic constants, spin–orbit effect and permanent and transition electric dipole moments

International audienc

An Evaluation of TiN Coatings Applied to Compressor Blades

NRC publication: Ye

Evaluation of Two TiN Coatings Applied to Compressor Blades

NRC publication: Ye