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1.
Nature ; 614(7949): 659-663, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36623548

RESUMO

Transmission spectroscopy1-3 of exoplanets has revealed signatures of water vapour, aerosols and alkali metals in a few dozen exoplanet atmospheres4,5. However, these previous inferences with the Hubble and Spitzer Space Telescopes were hindered by the observations' relatively narrow wavelength range and spectral resolving power, which precluded the unambiguous identification of other chemical species-in particular the primary carbon-bearing molecules6,7. Here we report a broad-wavelength 0.5-5.5 µm atmospheric transmission spectrum of WASP-39b8, a 1,200 K, roughly Saturn-mass, Jupiter-radius exoplanet, measured with the JWST NIRSpec's PRISM mode9 as part of the JWST Transiting Exoplanet Community Early Release Science Team Program10-12. We robustly detect several chemical species at high significance, including Na (19σ), H2O (33σ), CO2 (28σ) and CO (7σ). The non-detection of CH4, combined with a strong CO2 feature, favours atmospheric models with a super-solar atmospheric metallicity. An unanticipated absorption feature at 4 µm is best explained by SO2 (2.7σ), which could be a tracer of atmospheric photochemistry. These observations demonstrate JWST's sensitivity to a rich diversity of exoplanet compositions and chemical processes.

2.
Tob Control ; 12(3): 251-6, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12958381

RESUMO

OBJECTIVE: Comprehensive tobacco control policies for US colleges and universities have been proposed by several groups in order to counter the rising use of tobacco by students enrolled in these institutions. Student opinion of these policies is not known, and concern about student opposition is one barrier that deters administrators from adopting the policies. This study measured student support for recommended college tobacco control policies. DESIGN: Mailed survey of US college students (2001 Harvard School of Public Health College Alcohol Study). SETTING: 119 nationally representative, four-year colleges and universities in the USA. PARTICIPANTS: 10,904 randomly selected undergraduate students enrolled at participating schools. MAIN OUTCOME MEASURES: Students' opinion of 7 proposed tobacco control policies. RESULTS: A majority of students supported each policy. Over three quarters of students favoured smoke-free policies for all college buildings, residences, and dining areas, while 71% supported prohibiting tobacco advertising and sponsorship of campus social events, 59% favoured prohibiting tobacco sales on campus, and 51% supported smoke-free campus bars. All policies had more support among non-smokers than smokers (p < 0.001). Among smokers, support for policies was inversely related to intention to quit and intensity of tobacco consumption. Because college students' tobacco consumption is low, a majority of smokers favoured banning smoking in college buildings and dining areas and prohibiting tobacco marketing on campus. CONCLUSIONS: Student support for proposed campus tobacco control policies is strong, even among smokers, and broadly based across demographic subgroups. These findings should provide reassurance to college administrators who are considering adopting these policies.


Assuntos
Política de Saúde , Serviços de Saúde Escolar/organização & administração , Prevenção do Hábito de Fumar , Serviços de Saúde para Estudantes/organização & administração , Estudantes/psicologia , Adolescente , Adulto , Atitude Frente a Saúde , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Apoio Social , Estados Unidos
4.
Appl Opt ; 26(3): 475-91, 1987 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-20454160

RESUMO

The design, theory, operation, and characteristics of an optically phase-locked electronic speckle pattern interferometer (OPL-ESPI) are described. The OPL-ESPI system couples an optical phase-locked loop with an ESPI system to generate real-time equal Doppler speckle contours of moving objects from unstable sensor platforms. In addition, the optical phase-locked loop provides the basis for a new ESPI video signal processing technique which incorporates local oscillator phase shifting coupled with video sequential frame subtraction.

5.
Clin Exp Allergy ; 29(8): 1033-41, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10457105

RESUMO

BACKGROUND: There is evidence that people who use gas for cooking have reduced lung function and experience more respiratory symptoms than those who use other fuels for cooking. OBJECTIVES: To study the effect of the presence of a gas cooker in the home, during both childhood and adulthood, on respiratory symptoms, allergic sensitization and ventilatory function among young adults. METHODS: A sample of 1449 young adults born in Britain 3-9 March 1958, who have been followed from birth to ages 7, 11, 16, 23 and 33 years, were examined at home at age 34-35 years. FEV1 and FVC were measured before and 20 min after inhalation of 400 microg salbutamol, and skin prick tests performed with three allergen extracts (grass, Der p 1 and cat). An interview on respiratory symptoms and indoor environmental exposures was included. RESULTS: No association was found between gas cooking in childhood or adulthood and incidence or prognosis of asthma/wheeze, allergic sensitization or current severity of respiratory symptoms. Subjects who currently used gas for cooking had a significantly reduced FEV1 (- 70 mL, 95% CI +/- 56) but not FVC (- 35 mL, 95% CI +/- 61) compared with those who used electricity for cooking. This reduction in FEV1 was concentrated among men and current asthmatics. CONCLUSION: The use of gas for cooking is unlikely to be a major influence on respiratory morbidity in young adults.


Assuntos
Poluição do Ar em Ambientes Fechados/efeitos adversos , Culinária/instrumentação , Combustíveis Fósseis/efeitos adversos , Ventilação Pulmonar/fisiologia , Hipersensibilidade Respiratória/epidemiologia , Doenças Respiratórias/epidemiologia , Adulto , Criança , Estudos de Coortes , Feminino , Humanos , Exposição por Inalação , Masculino , Dióxido de Nitrogênio/efeitos adversos , Hipersensibilidade Respiratória/etiologia , Doenças Respiratórias/etiologia , Testes Cutâneos , Inquéritos e Questionários
6.
Int J Qual Health Care ; 11(1): 21-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10411286

RESUMO

BACKGROUND: Despite clinical guidelines penetrating every aspect of clinical practice and health policy, doubts persist over their ability to improve patient care. We have designed and tested a generic critical appraisal instrument, that assesses whether developers have minimized the biases inherent in creating guidelines, and addressed the requirements for effective implementation. DESIGN: Thirty-seven items describing suggested predictors of guideline quality were grouped into three dimensions covering the rigour of development, clarity of presentation (including the context and content) and implementation issues. The ease of use, reliability and validity of the instrument was tested on a national sample of guidelines for the management of asthma, breast cancer, depression and coronary heart disease, with 120 appraisers. A numerical score was derived to allow comparison of guidelines within and between diseases. RESULTS: The instrument has acceptable reliability (Cronbach's alpha coefficient, 0.68-0.84; intra-class correlation coefficient, (0.82-0.90)). The results provided some evidence of validity (Pearson's correlation coefficient between appraisers' dimension scores and their global assessment was 0.49 for dimension one, 0.63 for dimension two and 0.40 for dimension three). The instrument could differentiate between national and local guidelines and was easy to apply. There was variation in the performance of guidelines with most not achieving a majority of criteria in each dimension. CONCLUSIONS: Use of this instrument should encourage developers to create guidelines that reflect relevant research evidence more accurately. Potential users or groups adapting guidelines for local use could apply the instrument to help decide which one to follow. The National Health Service Executive is using the instrument to assist in deciding which guidelines to recommend to the UK National Health Service. This methodology forms the basis of a common approach to assessing guideline quality in Europe.


Assuntos
Aplicações da Informática Médica , Guias de Prática Clínica como Assunto/normas , Garantia da Qualidade dos Cuidados de Saúde/métodos , Estudos de Avaliação como Assunto , Humanos , Reprodutibilidade dos Testes , Medicina Estatal/normas , Reino Unido
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