259 research outputs found

    Familiar and unfamiliar face recognition in crested macaques (Macaca nigra).

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    Many species use facial features to identify conspecifics, which is necessary to navigate a complex social environment. The fundamental mechanisms underlying face processing are starting to be well understood in a variety of primate species. However, most studies focus on a limited subset of species tested with unfamiliar faces. As well as limiting our understanding of how widely distributed across species these skills are, this also limits our understanding of how primates process faces of individuals they know, and whether social factors (e.g. dominance and social bonds) influence how readily they recognize others. In this study, socially housed crested macaques voluntarily participated in a series of computerized matching-to-sample tasks investigating their ability to discriminate (i) unfamiliar individuals and (ii) members of their own social group. The macaques performed above chance on all tasks. Familiar faces were not easier to discriminate than unfamiliar faces. However, the subjects were better at discriminating higher ranking familiar individuals, but not unfamiliar ones. This suggests that our subjects applied their knowledge of their dominance hierarchies to the pictorial representation of their group mates. Faces of high-ranking individuals garner more social attention, and therefore might be more deeply encoded than other individuals. Our results extend the study of face recognition to a novel species, and consequently provide valuable data for future comparative studies

    Unitary Averaging with Fault and Loss Tolerance

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    We consider the impact of the unitary averaging framework on single and two-mode linear optical gates. We demonstrate that this allows a trade-off between the probability of success and gate fidelity, with perfect fidelity gates being achievable for a finite decrease in the probability of success, at least in principle. Furthermore, we show that the encoding and decoding errors in the averaging scheme can also be suppressed up to the first order. We also look at how unitary averaging can work in conjunction with existing error correction schemes. Specifically, we consider how parity encoding might be used to counter the extra loss due to the decreased probability of success, with the aim of achieving fault tolerance. We also consider how unitary averaging might be utilised to expand the parameter space in which fault tolerance may be achievable using standard fault tolerant schemes.Comment: 13 pages, 6 figure

    Reduced Gaze Following and Attention to Heads when Viewing a "Live" Social Scene

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    Social stimuli are known to both attract and direct our attention, but most research on social attention has been conducted in highly controlled laboratory settings lacking in social con- text. This study examined the role of social context on viewing behaviour of participants whilst they watched a dynamic social scene, under three different conditions. In two social groups, participants believed they were watching a live webcam of other participants. The socially-engaged group believed they would later complete a group task with the people in the video, whilst the non-engaged group believed they would not meet the people in the scene. In a third condition, participants simply free-viewed the same video with the knowl- edge that it was pre-recorded, with no suggestion of a later interaction. Results demonstrat- ed that the social context in which the stimulus was viewed significantly influenced viewing behaviour. Specifically, participants in the social conditions allocated less visual attention towards the heads of the actors in the scene and followed their gaze less than those in the free-viewing group. These findings suggest that by underestimating the impact of social context in social attention, researchers risk coming to inaccurate conclusions about how we attend to others in the real world

    Dipyridamole potentiates the in vitro activity of MTA (LY231514) by inhibition of thymidine transport

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    The novel pyrrolopyrimidine-based antifolate LY231514 (MTA), inhibits multiple folate-requiring enzymes including thymidylate synthase, glycinamide ribonucleotide formyltransferase and dihydrofolate reductase. Both thymidine and hypoxanthine are required to reverse MTA growth inhibition in leukaemia and colon cancer cells. Prevention of MTA growth inhibition by thymidine and/or hypoxanthine was investigated in two human lung (A549, COR L23) and two breast (MCF7, T47D) tumour cell lines, and the effect of the nucleoside/base transport inhibitor dipyridamole (DP) on thymidine and hypoxanthine rescue defined. MTA IC50values (continuous exposure three population doublings) were: A549–640 n M, COR L23–28 n M, MCF7–52 n M and T47D–46 n M. Thymidine (1 μM) completely prevented growth inhibition at the MTA IC50in all cell lines. At 10 × IC50, growth inhibition was only partially reversed by thymidine (≤ 10 μM); both thymidine and hypoxanthine (30 μM) being required for complete reversal, reflecting the multi-targeted nature of MTA. Growth inhibition by MTA was not affected by hypoxanthine alone. A non-toxic concentration (1 μM) of DP prevented thymidine/hypoxanthine rescue of MTA indicating that DP may potentiate MTA activity by preventing nucleoside and/or base salvage. Thymidine transport was inhibited by ≥ 89% by 1 μM DP in all cell lines, whereas hypoxanthine transport was inhibited only in A549 and MCF7 cells. Therefore, prevention of end-product reversal of MTA-induced growth inhibition by DP can be explained by inhibition of thymidine transport alone. © 2000 Cancer Research Campaig

    Improving Continuous-variable Quantum Channels with Unitary Averaging

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    A significant hurdle for quantum information and processing using bosonic systems are stochastic phase errors, which are likely to occur as the photons propagate through a channel. We propose and demonstrate a scheme of passive, linear optical unitary averaging for protecting Gaussian channels. The scheme requires only linear optical elements and vacuum detectors, and protects against a loss of purity, squeezing and entanglement. We present numerical simulations and analytical formula, tailored for currently relevant parameters with low noise levels, where our approximations perform exceptionally well. We also show the asymptotic nature of the protocol, highlighting both current and future relevance.Comment: 6 pages, 7 figures, 1 tabl

    'You just don't have the time to keep bringing them back, bringing them back': the experience of primary care dental professionals in England when treating young children with carious teeth

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    Introduction Caries in the primary dentition affects around one-quarter of children in England. There is uncertainty and varying practice regarding the management of these children within NHS primary dental care. Silver diamine fluoride (SDF) is an approach that is not well-adopted nationally. This study aims to explore the factors affecting treatment choices for caries management in young children within primary dental care, including the use of SDF. Methods Semi-structured interviews were carried out via video conferencing with general dental practitioners and therapists working in NHS primary care. The topic guide covered factors which influence the management of caries in primary teeth, with SDF-specific questions. These were transcribed verbatim and analysed using thematic analysis. Results A total of 13 interviews were conducted with dental professionals working across Yorkshire and the East Midlands. Decision-making for caries management was dependent on inter-related factors, which also influenced SDF use. Treatment decisions were taken on a case-by-case basis, but were influenced by the child, their parents, the dental professional and service factors, along with the clinical technique. Conclusion Many individual- and system-level factors influence treatment decisions for early childhood caries. However, issues relating to remuneration and governance appear to be specific barriers to adoption of SDF in primary dental care

    Development of the Malocclusion Impact Questionnaire (MIQ) to measure the oral health-related quality of life of young people with malocclusion: part 1 - qualitative inquiry

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    OBJECTIVES: To seek the views of adolescents with malocclusion about how the appearance and arrangement of their teeth affects their everyday life and to incorporate these views into a new Malocclusion Impact Questionnaire (MIQ). METHODS: Semi-structured interviews were undertaken with a purposive sample of 30 young people (10-16 years) referred for orthodontic treatment to two dental teaching hospitals. The interviews were recorded, transcribed and analysed using framework analysis. Several themes and sub themes were identified and these were used to identify items to include in the new measure. RESULTS: Three themes emerged which were: concerns about the appearance of their teeth, effect on social interactions and oral health/function. Participants expressed the view that their teeth did not look normal, causing them embarrassment and a lack of confidence, particularly when they were with their peers or having their photograph taken. Concerns regarding the potential effect of a malocclusion on oral health, in terms of food becoming stuck between crooked teeth, interferences when chewing and increased risk of damaging the teeth were also identified. The themes were used to generate individual items for inclusion in the questionnaire. CONCLUSIONS: Common themes relating to the impact of malocclusion on the lives of young people were identified and generated items for the new MIQ to measure the oral health-related quality of life of young people with malocclusion. Part 2 outlines the further development and testing of the MIQ
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