45 research outputs found

    From black strings to black holes: nuttier and squashed AdS5_5 solutions

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    We construct new solutions of the Einstein equations with negative cosmological constant in five spacetime dimensions. They smoothly emerge as deformations of the known AdS5_5 black strings. The first type of configurations can be viewed as the d=4d=4 Taub-NUT-AdS solutions uplifted to five dimensions, in the presence of a negative cosmological constant. We argue that these solutions provide the gravity dual for a N=4{\cal N}=4 super-Yang-Mills theory formulated in a d=4d=4 homogeneous G\"odel-type spacetime background. A different deformation of the AdS5_5 black strings leads to squashed AdS black holes and their topological generalizations. In this case, the conformal infinity is the product of time and a circle-fibration over a base space that is a two-dimensional Einstein space.Comment: 19 pages, 7 figure

    Model-based analyses: Promises, pitfalls, and example applications to the study of cognitive control

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    We discuss a recent approach to investigating cognitive control, which has the potential to deal with some of the challenges inherent in this endeavour. In a model-based approach, the researcher defines a formal, computational model that performs the task at hand and whose performance matches that of a research participant. The internal variables in such a model might then be taken as proxies for latent variables computed in the brain. We discuss the potential advantages of such an approach for the study of the neural underpinnings of cognitive control and its pitfalls, and we make explicit the assumptions underlying the interpretation of data obtained using this approach

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Tremor ortostático

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    Tremor ortostático (TO) é v.m novo tipo de tremor, irregular e de alta freqüência, recentemente descrito, que afeta grupamentos musculares antagonistas nos membros inferiores, desde que seja mantida a postura ereta. Descrevemos dois novos casos deste tipo peculiar de tremor, que pode não ser tão incomum quanto até então suposto. Enfatizamos suas principais características diagnosticas e semiológicas. O TO pode compartilhar algum mecanismo fisiopatológico básico com os tremores da variedade heredofamilial essencial clássica
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