45 research outputs found

    Ergodicity-breaking reveals time optimal decision making in humans

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    Ergodicity describes an equivalence between the expectation value and the time average of observables. Applied to human behaviour, ergodic theories of decision-making reveal how individuals should tolerate risk in different environments. To optimise wealth over time, agents should adapt their utility function according to the dynamical setting they face. Linear utility is optimal for additive dynamics, whereas logarithmic utility is optimal for multiplicative dynamics. Whether humans approximate time optimal behavior across different dynamics is unknown. Here we compare the effects of additive versus multiplicative gamble dynamics on risky choice. We show that utility functions are modulated by gamble dynamics in ways not explained by prevailing decision theory. Instead, as predicted by time optimality, risk aversion increases under multiplicative dynamics, distributing close to the values that maximise the time average growth of wealth. We suggest that our findings motivate a need for explicitly grounding theories of decision-making on ergodic considerations.Comment: 43 pages including supplementary methods & material

    Relationship between the Clinical Frailty Scale and short-term mortality in patients ≥ 80 years old acutely admitted to the ICU: a prospective cohort study.

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    BACKGROUND: The Clinical Frailty Scale (CFS) is frequently used to measure frailty in critically ill adults. There is wide variation in the approach to analysing the relationship between the CFS score and mortality after admission to the ICU. This study aimed to evaluate the influence of modelling approach on the association between the CFS score and short-term mortality and quantify the prognostic value of frailty in this context. METHODS: We analysed data from two multicentre prospective cohort studies which enrolled intensive care unit patients ≥ 80 years old in 26 countries. The primary outcome was mortality within 30-days from admission to the ICU. Logistic regression models for both ICU and 30-day mortality included the CFS score as either a categorical, continuous or dichotomous variable and were adjusted for patient's age, sex, reason for admission to the ICU, and admission Sequential Organ Failure Assessment score. RESULTS: The median age in the sample of 7487 consecutive patients was 84 years (IQR 81-87). The highest fraction of new prognostic information from frailty in the context of 30-day mortality was observed when the CFS score was treated as either a categorical variable using all original levels of frailty or a nonlinear continuous variable and was equal to 9% using these modelling approaches (p < 0.001). The relationship between the CFS score and mortality was nonlinear (p < 0.01). CONCLUSION: Knowledge about a patient's frailty status adds a substantial amount of new prognostic information at the moment of admission to the ICU. Arbitrary simplification of the CFS score into fewer groups than originally intended leads to a loss of information and should be avoided. Trial registration NCT03134807 (VIP1), NCT03370692 (VIP2)

    Model tests of Project Mohole drilling platform : final report

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    http://deepblue.lib.umich.edu/bitstream/2027.42/6602/5/bac9667.0001.001.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/6602/4/bac9667.0001.001.tx

    Über Chinuclidine

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    An official American Thoracic Society and European Respiratory Society policy statement : disparities in respiratory health

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    Health disparities, defined as a significant difference in health between populations, are more common for diseases of the respiratory system than for those of other organ systems, because of the environmental influence on breathing and the variation of the environment among different segments of the population. The lowest social groups are up to 14 times more likely to have respiratory diseases than are the highest. Tobacco smoke, air pollution, environmental exposures, and occupational hazards affect the lungs more than other organs and occur disproportionately in ethnic minorities and those with lower socioeconomic status. Lack of access to quality healthcare contributes to disparities. The executive committees of the American Thoracic Society (ATS) and European Respiratory Society (ERS) established a writing committee to develop a policy on health disparities. The document was reviewed, edited, and approved by their full executive committees and boards of directors of the societies. This document expresses a policy to address health disparities by promoting scientific inquiry and training, disseminating medical information and best practices, and monitoring and advocating for public respiratory health. The ERS and the ATS have strong international commitments and work with leaders from governments, academia, and other organisational bodies to address and reduce avoidable health inequalities. Their training initiatives improve the function of healthcare systems and health equality. Both the ATS and the ERS support all aspects of this document, confer regularly, and act together when possible, but the activities to bring about change may vary because of the differences in the continents where the two organisations carry out most of their activities. The ATS and ERS pledge to frame their actions to reduce respiratory health disparities. The vision of the ATS and ERS is that all persons attain better and sustained respiratory health. They call on all their members and other societies to join in this commitment. Copyrigh

    An Official American Thoracic Society/European Respiratory Society Policy Statement : Disparities in Respiratory Health

    No full text
    Background: Health disparities, defined as a significant difference in health between populations, are more common for diseases of the respiratory system than for those of other organ systems, because of the environmental influence on breathing and the variation of the environment among different segments of the population. The lowest social groups are up to 14 times more likely to have respiratory diseases than are the highest. Tobacco smoke, air pollution, environmental exposures, and occupational hazards affect the lungs more than other organs, and occur disproportionately in ethnic minorities and those with lower socioeconomic status. Lack of access to quality health care contributes to disparities. Methods: The executiv ecommittees of the American Thoracic Society (ATS) and European Respiratory Society (ERS) established a writing committee to develop a policy on health disparities. The document was reviewed, edited, and approved by the full executive committees and boards of directors of the societies. Results: This document expresses a policy to address health disparities by promoting scientific inquiry and training, disseminating medical information and best practices, and monitoring and advocating for public respiratory health. ERS and ATS have strong international commitments, and work with leaders from governments academia, and organizations to address and reduce avoidable health inequalities. Their training initiatives improve the function of health care systems and health equality. Both the ATS and ERS support all aspects of this document, confer regularly, and act together when possible, but the activities to bring about change may vary because of the differences in the continents where the two organizations carry out most of their activities. Conclusions: The ATS and ERS pledge to frame their actions to reduce respiratory health disparities. The vision of the ATS and ERS is that all persons attain better and sustained respiratory health. They call on all their members and other societies to join in this commitment

    Genetic susceptibility to schizophrenia through neuroinflammatory pathways is associated with retinal thinning: Findings from the UK-Biobank.

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    The human retina is part of the central nervous system and can be easily and noninvasively imaged through optical coherence tomography. Imaging the retina may provide insights on central nervous system related disorders such as schizophrenia. Here, our objective was to investigate if variations in retinal phenotypes could be attributed to common genetic variations conveying a risk of schizophrenia as measured by polygenic risk scores. We used population data from the UK Biobank, including White British and Irish individuals without diagnosed schizoprenia, and estimated a polygenic risk score for schizophrenia based on the newest genome-wide association study (PGC release 2022). We hypothesized that greater genetic susceptibility to schizophrenia is associated with retinal thinning, especially within the macula. To gain additional mechanistic insights, we conducted pathway-specific polygenic risk score associations analyses, focusing on gene pathways that are related to schizophrenia. Of 65484 individuals recruited, 48208 participants with available matching imaging-genetic data were included in the analysis of whom 22427 (53.48%) were female and 25781 (46.52%) were male. 5148 individuals were excluded on the basis of incomplete optical coherence tomography data (for all phenotypes), 198 individuals based on the use of antipsychotics and 197 individuals with schizophrenia, schizotypal- and delusional disorders. Our robust principal component regression results showed that polygenic risk scores for schizophrenia were associated with retinal thinning while controlling for confounding factors (b = -0.03, p = 0.007). Similarly, we found that polygenic risk for schizophrenia specific to neuroinflammation gene sets revealed significant associations with retinal thinning (b = -0.03, self-contained p = 0.041 (reflecting the level of association), competitive p = 0.05 (reflecting the level of enrichment)). These results go beyond previous studies suggesting a relationship between manifested schizophrenia and retinal phenotypes. They indicate that the retina is a mirror reflecting the genetic complexities of schizophrenia. These associations also suggest the potential involvement of the neuroinflammatory pathway, with indications of genetic overlap in certain retinal phenotypes. The findings further indicate that this gene pathway in individuals with a high polygenic risk for schizophrenia could contribute through acute-phase proteins to structural changes in the retina
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