Browsing by Subject "REAL"

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  • Cai, Runlong; Yan, Chao; Worsnop, Douglas; Bianchi, Federico; Kerminen, Veli-Matti; Liu, Yongchun; Wang, Lin; Zheng, Jun; Kulmala, Markku; Jiang, Jingkun (2021)
    New particle formation (NPF) occurs frequently in various atmospheric environments and it is a major source of ultrafine particles. This study proposes an indicator, I, for the occurrence of NPF in the atmosphere based on the mechanism of H2SO4-amine nucleation. It characterizes the synergistic effects of the governing factors for H2SO4-amine nucleation, including H2SO4 concentration, amine concentrations, the stability of H2SO4-amine clusters, and aerosol surface area concentration. Long-term measurements in urban Beijing were used to validate this indicator. Good consistency was found between this indicator and the occurrence of NPF. NPF was usually observed with I > 1 for typical conditions in urban Beijing. The derivation and expressions of I also indicate a good positive association between the H2SO4 dimer concentration and NPF, as also verified by measurements. I was shown to be also applicable in urban Shanghai. Copyright (c) 2021 American Association for Aerosol Research
  • TOTEM Collaboration; Antchev, G.; Berretti, M.; Garcia, F.; Heino, J.; Helander, P.; Lauhakangas, R.; Naaranoja, T.; Oljemark, F.; Österberg, K.; Saarikko, H.; Welti, J. (2019)
    The TOTEM experiment at the LHC has performed the first measurement at root s = 13 TeV of the rho parameter, the real to imaginary ratio of the nuclear elastic scattering amplitude at t = 0, obtaining the following results: rho = 0.09 +/- 0.01 and rho = 0.10 +/- 0.01, depending on different physics assumptions and mathematical modelling. The unprecedented precision of the rho measurement, combined with the TOTEM total cross-section measurements in an energy range larger than 10 TeV (from 2.76 to 13 TeV), has implied the exclusion of all the models classified and published by COMPETE. The rho results obtained by TOTEM are compatible with the predictions, from other theoretical models both in the Regge-like framework and in the QCD framework, of a crossing-odd colourless 3-gluon compound state exchange in the t-channel of the proton-proton elastic scattering. On the contrary, if shown that the crossing-odd 3-gluon compound state t-channel exchange is not of importance for the description of elastic scattering, the rho value determined by TOTEM would represent a first evidence of a slowing down of the total cross-section growth at higher energies. The very low-vertical bar t vertical bar reach allowed also to determine the absolute normalisation using the Coulomb amplitude for the first time at the LHC and obtain a new total proton-proton cross-section measurement sigma(tot) = (110.3 +/- 3.5) mb, completely independent from the previous TOTEM determination. Combining the two TOTEM results yields sigma(tot) = (110.5 +/- 2.4) mb.
  • Talwar, Shalini; Dhir, Amandeep; Singh, Dilraj; Virk, Gurnam; Salo, Jari (2020)
    Sharing of fake news on social media platforms is a global concern, with research offering little insight into the motives behind such sharing. This study adopts a mixed-method approach to explore fake-news sharing behaviour. To begin with, qualitative data from 58 open-ended essays was analysed to identify six behavioural manifestations associated with sharing fake news. Thereafter, research model hypothesizing the association between these behaviours was proposed using the honeycomb framework and the third-person effect hypothesis. Age and gender were the control variables. Two data sets obtained from cross-sectional surveys with 471 and 374 social media users were utilized to test the proposed model. The study results suggest that instantaneous sharing of news for creating awareness had positive effect on sharing fake news due to lack of time and religiosity. However, authenticating news before sharing had no effect on sharing fake news due to lack of time and religiosity. The study results also suggest that social media users who engage in active corrective action are unlikely to share fake news due to lack of time. These results have significant theoretical and practical implications.
  • Ptchelkine, Denis; Gillum, Ashley; Mochizuki, Tomohiro; Lucas-Staat, Soizick; Liu, Ying; Krupovic, Mart; Phillips, Simon E. V.; Prangishvili, David; Huiskonen, Juha T. (2017)
    Archaeal viruses have evolved to infect hosts often thriving in extreme conditions such as high temperatures. However, there is a paucity of information on archaeal virion structures, genome packaging, and determinants of temperature resistance. The rod-shaped virus APBV1 (Aeropyrum pernix bacilliform virus 1) is among the most thermostable viruses known; it infects a hyperthermophile Aeropyrum pernix, which grows optimally at 90 degrees C. Here we report the structure of APBV1, determined by cryo-electron microscopy at near-atomic resolution. Tight packing of the major virion glycoprotein (VP1) is ensured by extended hydrophobic interfaces, and likely contributes to the extreme thermostability of the helical capsid. The double-stranded DNA is tightly packed in the capsid as a left-handed superhelix and held in place by the interactions with positively charged residues of VP1. The assembly is closed by specific capping structures at either end, which we propose to play a role in DNA packing and delivery.