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1.
Sci Rep ; 8(1): 4666, 2018 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-29568057

RESUMO

Ocean plastic can persist in sea surface waters, eventually accumulating in remote areas of the world's oceans. Here we characterise and quantify a major ocean plastic accumulation zone formed in subtropical waters between California and Hawaii: The Great Pacific Garbage Patch (GPGP). Our model, calibrated with data from multi-vessel and aircraft surveys, predicted at least 79 (45-129) thousand tonnes of ocean plastic are floating inside an area of 1.6 million km2; a figure four to sixteen times higher than previously reported. We explain this difference through the use of more robust methods to quantify larger debris. Over three-quarters of the GPGP mass was carried by debris larger than 5 cm and at least 46% was comprised of fishing nets. Microplastics accounted for 8% of the total mass but 94% of the estimated 1.8 (1.1-3.6) trillion pieces floating in the area. Plastic collected during our study has specific characteristics such as small surface-to-volume ratio, indicating that only certain types of debris have the capacity to persist and accumulate at the surface of the GPGP. Finally, our results suggest that ocean plastic pollution within the GPGP is increasing exponentially and at a faster rate than in surrounding waters.


Assuntos
Monitoramento Ambiental/métodos , Resíduos de Alimentos , Plásticos/efeitos adversos , Poluentes Químicos da Água/efeitos adversos , California , Havaí , Modelos Teóricos , Oceano Pacífico , Plâncton , Estudos de Amostragem , Imagens de Satélites/métodos , Espectrofotometria Infravermelho , Resíduos , Poluição Química da Água , Vento
2.
Eur Arch Otorhinolaryngol ; 270(2): 565-70, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22588193

RESUMO

The upper airway respiratory diseases (i.e. common cold, allergic rhinitis, nonallergic/vasomotor rhinitis, acute and chronic rhinosinusitis and nasal polyposis) in which nasal congestion is a common symptom are often undertreated due to the frequent inadequate efficacy and safety concern with current therapies. In scientific literature, few studies seem to support the hypothesis that nasal inhalatory treatment with thermal water promotes the improvement of nasal symptoms, even if the mechanisms by which the improvement from SPA therapy can be expected remain debated. A prospective comparative study with a pre-post design has been performed consecutively enrolling 33 (males 70 %) patients of both genders older than 12 years of age, affected by chronic sinonasal inflammation. All patients underwent a 14-days course of radioactive water warm vapour inhalations followed by nasal aerosol of the same thermal water 10 min each once/day at Merano Therme. At the beginning and end of the study, in all the subjects, nasal function evaluation by active anterior rhinomanometry, mucociliary transport time (MCTt) determination and nasal cytology were performed. After the inhalatory treatment, the mucociliary function was improved and the pathologic mucociliary transport times recorded at the beginning of the study being significantly reduced to physiologic ones. Besides, before treatment, the cytologic picture showed an inflammatory cell infiltration (eosinophils, neutrophils with/without bacteria, mast cells) in 37 % of patients; after therapy in 66 % of these patients, the rhinocytogram was normal. Our results suggest, according to the literature data, that SPA therapy with radioactive water could represent an alternative choice in chronic inflammatory diseases of the upper airways, nonresponsive to pharmacological therapy.


Assuntos
Balneologia , Rinite/terapia , Sinusite/terapia , Doença Crônica , Feminino , Humanos , Masculino , Depuração Mucociliar , Mucosa Nasal/patologia , Obstrução Nasal/etiologia , Rinite/complicações , Rinite/fisiopatologia , Sinusite/complicações , Sinusite/fisiopatologia
4.
Appl Opt ; 31(22): 4554-8, 1992 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20725458

RESUMO

In principle, the real n and imaginary k parts of the complex refractive index of a crystal can be determined by measuring, when possible, its transmission and reflection spectra. We show that it is possible to derive the frequency dependence of n and k in a simple way by using exact expressions for the interference-free transmittance and reflectance to describe low-resolution data. We also derive n and k data starting from one high-resolution spectrum. As an example, we have measured the roomtemperature transmittance and reflectance of MgO in the far-infrared region. Reliable n and k data are then obtained in the frequency region 50-250 cm(-1).

6.
Phys Rev B Condens Matter ; 39(12): 8622-8627, 1989 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9947576
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