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1.
Nat Commun ; 14(1): 3707, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37349297

RESUMO

Few studies report the occurrence of microplastics (MP), including tire wear particles (TWP) in the marine atmosphere, and little data is available regarding their size or sources. Here we present active air sampling devices (low- and high-volume samplers) for the evaluation of composition and MP mass loads in the marine atmosphere. Air was sampled during a research cruise along the Norwegian coast up to Bear Island. Samples were analyzed with pyrolysis-gas chromatography-mass spectrometry, generating a mass-based data set for MP in the marine atmosphere. Here we show the ubiquity of MP, even in remote Arctic areas with concentrations up to 37.5 ng m-3. Cluster of polyethylene terephthalate (max. 1.5 ng m-3) were universally present. TWP (max. 35 ng m-3) and cluster of polystyrene, polypropylene, and polyurethane (max. 1.1 ng m-3) were also detected. Atmospheric transport and dispersion models, suggested the introduction of MP into the marine atmosphere equally from sea- and land-based emissions, transforming the ocean from a sink into a source for MP.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Polipropilenos
2.
Atherosclerosis ; 195(2): e203-9, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17720168

RESUMO

INTRODUCTION: Carotid Intima-Media Thickness (IMT) is used widely to assess an individual's risk of myocardial infarction and stroke. Although significant associations have been showed, IMT as used in major studies does not improve prediction of cardiovascular events much compared to traditional risk factors. Therefore, a new approach to IMT-measurements is sought-after by examining the wall structure continuously throughout several heart cycles. MATERIALS AND METHODS: Computerized single-image analysis (IA) and sequential analysis (SA) were used to assess latter's capability in predicting risk of cardiovascular disease and to compare both. Healthy subjects (mean+/-S.D., age 46.1+/-5.6 years, n=490) were compared with subjects suffering from confirmed coronary artery disease (CAD) (mean+/-S.D., age 47.3+/-6.2 years, n=51). RESULTS: SA could differentiate between both groups better then single IA, especially when looking at the maximal and mean IMT-values (SA<-->IA, p<0.01<-->p<0.05). The area under the curve (AUC) for maximal and mean IMT was greater for sequences then for single images as well. DISCUSSION: Due to our findings sequential analysis can offer an extensive and complete examination of the carotid wall with a maximal reduction of bias. Commonly used IA may disguise vascular conditions and therefore the patient's risk, since IMT-values, as proven with SA, seems to usually be higher. Therefore, the need for further studies arises, examining if and to what extend common IMT-studies underestimate differences between groups.


Assuntos
Doenças das Artérias Carótidas/diagnóstico por imagem , Artéria Carótida Primitiva/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Túnica Íntima/diagnóstico por imagem , Túnica Média/diagnóstico por imagem , Adulto , Doenças das Artérias Carótidas/patologia , Artéria Carótida Primitiva/patologia , Estudos de Casos e Controles , Doença da Artéria Coronariana/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Medição de Risco , Túnica Íntima/patologia , Túnica Média/patologia , Ultrassonografia
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