5 research outputs found
Effect of sedation with inhaled anaesthetics on cognitive and psychiatric outcomes in critically ill adults: a systematic review protocol
Introduction The COVID-19 pandemic has renewed interest in the use of inhaled anaesthetics for sedation of ventilated critically ill patients. Preliminary data show that inhaled anaesthetics reduce lung inflammation, time to extubation and intensive care unit length of stay compared with intravenous sedatives. However, the impact of inhaled anaesthetics on cognitive and psychiatric outcomes is not well described in this setting. Randomised controlled trials are underway to establish if inhaled anaesthetics affect these and other patient and health system outcomes. Our aim is to summarise the known effects of inhaled sedatives on cognitive and psychiatric outcomes. Methods and analysis In this systematic review, we will use MEDLINE, EMBASE, and PsycINFO to identify studies from 1970 to 2021 that assessed cognitive and psychiatric outcomes in critically ill adult patients sedated with inhaled anaesthetics. We will include case series, observational and cohort studies and randomised controlled trials. We will exclude case studies due to the heterogeneity of reporting in these studies. For randomised controlled trials comparing inhaled to intravenous sedation, we will report cognitive and psychiatric outcomes for both study arms. Studies will be selected based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist. Data will be extracted using a standardised data extraction tool by two independent reviewers. Studies will be assessed for bias using the Cochrane risk of bias tool for randomised controlled trials, or the Newcastle-Ottawa Scale for cohort and case-control studies. Findings will be reported according to outcome and descriptive statistics will be used to illustrate findings in a narrative fashion. Ethics and dissemination The systematic review uses published data and therefore does not require ethics approval. Results will be disseminated via publication in peer-reviewed journals and presentation at conferences related to the field. PROSPERO registration number CRD42021236455
Dimer Models and Integrable Systems
We explore various aspects of the correspondence between dimer models and
integrable systems recently introduced by Goncharov and Kenyon. Dimer models
give rise to relativistic integrable systems that match those arising from 5d
N=1 gauge theories studied by Nekrasov. We apply the correspondence to dimer
models associated to the Y^{p,0} geometries, showing that they give rise to the
relativistic generalization of the periodic Toda chain originally studied by
Ruijsenaars. The correspondence reduces the calculation of all conserved
charges to a straightforward combinatorial problem of enumerating
non-intersecting paths in the dimer model. We show how the usual periodic Toda
chain emerges in the non-relativistic limit and how the Lax operator
corresponds to the Kasteleyn matrix of the dimer model. We discuss how the
dimer models for general Y^{p,q} manifolds give rise to other relativistic
integrable systems, generalizing the periodic Toda chain and construct the
integrable systems for general Y^{p,p} explicitly. The impurities introduced in
the construction of Y^{p,q} quivers are identified with impurities in twisted
sl(2) XXZ spin chains. Finally we discuss how the physical concept of higgsing
a dimer model provides an efficient method for producing new integrable systems
starting from known ones. We illustrate this idea by constructing the
integrable systems for higgsings of Y^{4,0}.Comment: 29 pages, 16 figures. v2: typos fixe
Global zoogeography of fragile macrozooplankton in the upper 100-1000 m inferred from the underwater video profiler
4th International Zooplankton Production Symposium, Hiroshima, JAPAN, MAY 28-JUN 01, 2007International audienceMesopelagic gelatinous zooplankton fauna are insufficiently known because of inappropriate and infrequent sampling, but may have important trophic roles. In situ imaging systems and undersea vehicles have been used to investigate their diversity, distribution, and abundance. The use of different platforms, however, restricts the comparison of data from different regions. Starting in 2001, the underwater video profiler (UVP) was deployed during 12 cruises in six oceanic regimes (Mediterranean Sea, North Atlantic shelves, Mid-Atlantic Ridge, tropical Pacific Ocean, eastern Indian Ocean, and Subantarctic Ocean) to determine the vertical distribution of organisms in the upper 1000 m. Nine oceanic regions were identified based on the hydrological properties of the water column. They correspond to nine of the biogeochemical provinces defined by Longhurst. In all, 21 morphotypes were recognized: sarcodines (eight groups), ctenophores (two groups), siphonophores, medusae (five groups), crustaceans (one group), chaetognaths, appenclicularians, salps, and fish. The similarity in the community assemblages of zooplankton in the 100-1000 m layer was significantly greater within regions than between regions, in most cases. The regions with comparable composition were located in the North Atlantic with adjacent water masses, suggesting that the assemblages were either mixed by advective transport or that environmental conditions were similar in mesopelagic layers. The data suggest that the spatial structuring of mesopelagic macrozooplankton occurs on large scales (e.g. basin scales) but not necessarily on smaller scales (e.g. oceanic front)