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1.
Nature ; 625(7993): 51-54, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37967578

RESUMO

WASP-107b is a warm (approximately 740 K) transiting planet with a Neptune-like mass of roughly 30.5 M⊕ and Jupiter-like radius of about 0.94 RJ (refs. 1,2), whose extended atmosphere is eroding3. Previous observations showed evidence for water vapour and a thick, high-altitude condensate layer in the atmosphere of WASP-107b (refs. 4,5). Recently, photochemically produced sulfur dioxide (SO2) was detected in the atmosphere of a hot (about 1,200 K) Saturn-mass planet from transmission spectroscopy near 4.05 µm (refs. 6,7), but for temperatures below about 1,000 K, sulfur is predicted to preferably form sulfur allotropes instead of SO2 (refs. 8-10). Here we report the 9σ detection of two fundamental vibration bands of SO2, at 7.35 µm and 8.69 µm, in the transmission spectrum of WASP-107b using the Mid-Infrared Instrument (MIRI) of JWST. This discovery establishes WASP-107b as the second irradiated exoplanet with confirmed photochemistry, extending the temperature range of exoplanets exhibiting detected photochemistry from about 1,200 K down to about 740 K. Furthermore, our spectral analysis reveals the presence of silicate clouds, which are strongly favoured (around 7σ) over simpler cloud set-ups. Furthermore, water is detected (around 12σ) but methane is not. These findings provide evidence of disequilibrium chemistry and indicate a dynamically active atmosphere with a super-solar metallicity.

2.
Eur J Cardiovasc Nurs ; 17(3): 255-261, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28980478

RESUMO

BACKGROUND: Delirium is a common temporary mental disorder that often occurs in patients who undergo cardiac surgery. It is important to prevent the negative side effects of delirium by identifying high-risk patients before surgery. Koster and colleagues designed a risk model to identify patients with an increased risk of postoperative delirium after cardiac surgery. AIM: The aim of this study was to validate the risk model for delirium and further improve the risk model. METHODS: A delirium risk checklist containing predictors associated with postoperative delirium was used during the preoperative outpatient screening in 329 patients. The delirium observation screening scale was used preoperatively and postoperatively to assess delirium. RESULTS: Compared with the model of Koster and colleagues age greater than 70 years and a history of delirium were confirmed as statistically significant predictors of postoperative delirium, while cognitive impairment and alcohol abuse were almost significant factors. The European system for cardiac operative risk evaluation (EuroSCORE), comorbidity and type of surgery could not predict a postoperative delirium again. The area under the curve of this model was 0.79 (95% confidence interval (CI) 0.73-0.86; P<0.001). Based on the data of this study the model was improved with the following independent predictors of postoperative delirium: age, more than one comorbidity, history of delirium and a lower standardised mini mental state examination score as with an area under the curve of 0.79 (95% CI 0.73-0.85; P<0.001). CONCLUSION: The risk model could not be fully validated. It is difficult to validate a risk model over time; there are different circumstances such as the increased focus on the prevention of delirium.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/psicologia , Delírio/etiologia , Complicações Pós-Operatórias/etiologia , Idoso , Alcoolismo/complicações , Lista de Checagem , Disfunção Cognitiva/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco
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