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An Apatite-Group Praseodymium Carbonate Fluoroxybritholite: hydrothermal synthesis, crystal structure, and implications for natural and synthetic Britholites
Get PDFBritholites are the lanthanide–silica-rich end-members of the apatite group, commonly studied for their optical properties. Here, we show ∼50–100 μm single crystals synthesized hydrothermally at 650–500 °C and 500–300 MPa composed of a solid solution between Ca2Pr3(SiO4)3F–fluorbritholite and CaPr4(SiO4)3O–oxybritholite, with a significant carbonate component substitution, via C4+ replacing Si4+. Single-crystal X-ray diffraction and density functional theory computations show that a planar carbonate group occupies the face of a now-vacant silica tetrahedron. This modifies Pr–O bond lengths, diversifying lanthanide optical emission wavelengths. Our britholite was synthesized in geologically reasonable conditions and compositions, suggesting that carbonated oxybritholites could exist as yet-unrecognized natural minerals
Sentiment and time-series analysis of direct-message conversations
Get PDFSocial media and mobile communications in general are an extremely rich source of digital forensic information. We present our new framework for analysing this resource with an innovative combination of time series and text mining methods. The framework is intended to create a tool to analyse and operationally summarise extended trails of social media messages, thus enabling investigators for the first time to drill down into specific moments at which sentiment analysis has detected a change of tone indicative of a particularly strong and significant response. Crucially, the method will give investigators an opportunity to reduce the time and resource commitment required for ongoing and hands-on analysis of digital communications on media such as Texts/SMS, WhatsApp and Messenger
A dissociation between the effects of expectations and attention in selective visual processing
Get PDFIt is often claimed that probabilistic expectations affect visual perception directly, without mediation by selective attention. However, these claims have been disputed, as effects of expectation and attention are notoriously hard to dissociate experimentally. In this study, we used a new approach to separate expectations from attention. In four experiments (N=60), participants searched for a target in a rapid serial visual presentation (RSVP) stream and had to identify a digit or a letter defined by a low-level cue (colour or shape). Expectations about the target’s alphanumeric category were probabilistically manipulated. Since category membership is a high-level feature and since the target was embedded among many distractors that shared its category, targets from the expected category should not attract attention more than targets from the unexpected category. In the first experiment, these targets were more likely to be identified relative to targets from the unexpected category. Importantly, in the following experiments, we also included behavioural and electrophysiological indices of attentional guidance and engagement. This allowed us to examine whether expectations also modulated these or earlier attentional processes. Results showed that category-based expectations had no modulatory effects on attention, and only affected processing at later encoding-related stages. Alternative interpretation of expectation effects in terms of repetition priming or response bias were also ruled out. These observations provide new evidence for attention-independent direct expectation effects on perception. We suggest that expectations can adjust the threshold required for encoding expectations-congruent information, thereby affecting the speed with which target objects are encoded in working memory
Behind the screen: perceptions and experiences of online fraud victimisation
Get PDFFraud is now the most commonly experienced crime in the UK, making up over 40 per cent of all recorded crime. Instances of fraud have risen substantially over the last decade, from 510,403 offences recorded in the year ending 2013 to 1.16 million offences recorded in the year ending 2023,2 with online fraud contributing significantly to the increase (the Crime Survey for England and Wales estimates that over 60 per cent of cyber incidents take place online). Yet our understanding of online fraud in particular — its typology, scale and impact — is limited.
Crest Advisory, in partnership with the Police Foundation and Birkbeck, University of London (Institute for Crime and Justice Policy Research), and with funding from the Dawes Trust, is carrying out a large research project into tackling online fraud.
The first part of our project focuses on developing a better understanding of the impact of online fraud on victims and the wider public. In September 2023, Crest published findings from large-scale online surveys of the public and small and medium enterprises (SMEs)3 which explored public perceptions and experiences of online fraud. This report presents the findings from interviews with 20 victims and 12 focus groups (with 96 members of the public) to build on the survey findings and deepen our insight and knowledge of online fraud victimisation and its impact. It addresses a key gap as most existing studies do not distinguish between online and offline fraud victimisation, in part because many fraudulent activities combine offline and online elements. Key findings from the interviews and focus groups are set out in this report
Some personal notes on the REF OA mandate for books
No full textA few thoughts on the REF OA mandate for book
Haptic experience of bodies alters body perception
Get PDFResearch on media’s effects on body perception has mainly focused on the role of vision of extreme body types. However, haptics is a major part of the way children experience bodies. Playing with unrealistically thin dolls has been linked to the emergence of body image concerns, but the perceptual mechanisms remain unknown. We explore the effects of haptic experience of extreme body types on body perception, using adaptation aftereffects. Blindfolded participants judged whether the doll-like stimuli explored haptically were thinner or fatter than the average body before and after adaptation to an underweight or overweight doll. In a second experiment, participants underwent a traditional visual adaptation paradigm to extreme bodies, using stimuli matched to those in Experiment 1. For both modalities, after adaptation to an underweight body test bodies were judged as fatter. Adaptation to an overweight body produced opposite results. For the first time, we show adiposity aftereffects in haptic modality, analogous to those established in vision, using matched stimuli across visual and haptic paradigms
Forum on Heikki Patomäki’s World Statehood: The Future of World Politics
Get PDFIn this forum, six scholars discuss Heikki Patomäki’s book World Statehood: The Future of World Politics, published in 2023
Objectives pursued by European football clubs: hiring talent to generate income through victories and media exposure
Get PDFDesign/methodology/approach: This paper applies SEM (path analysis) techniques to re-examine what is the more realistic description of football club owners’ decisions when hiring talent. Our database comprises teams from the first division of four top European football leagues: 80 observations per season during the pre-Covid period spanning from 2009/10 to 2017/18.
Purpose: The paper revisits the debate on the priorities of football clubs in talent hiring with respect to maximizing sporting performance or economic profitability. Based on the degree of media exposure of the clubs, we examine whether the clubs’ objectives include, in addition to the classic twofold choice, the aspiration of club managers to gain popularity through media exposure.
Findings: The results suggest that, when recruiting players, in addition to considering the two classic objectives (wins and profits), club owners also seem to aim expanding the media exposure and
popularity of their clubs. Our study reveals that, to explain talent hiring decisions in football, the ability to attract media attention is as crucial as sporting performance could be. Furthermore, by
examining the direct, indirect and total effects on annual revenue, we found that our media visibility index performs a mediation effect connecting sports performance and revenue.
Originality/value: An innovative feature of our analysis is the use of the MERIT media visibility index, which jointly captures the on
-field and off-field players’ skills. The consistency and robustness of the results derive from the various specifications of the estimated models
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