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1.
Environ Pollut ; 229: 329-338, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28605720

RESUMO

In April of 2010, the Macondo well blowout in the northern Gulf of Mexico resulted in an unprecedented release of oil into the water column at a depth of approximately 1500 m. A time series of surface and subsurface sediment samples were collected to the northwest of the well from 2010 to 2013 for molecular biomarker and bulk carbon isotopic analyses. While no clear trend was observed in subsurface sediments, surface sediments (0-3 cm) showed a clear pattern with total concentrations of n-alkanes, unresolved complex mixture (UCM), and petroleum biomarkers (terpanes, hopanes, steranes) increasing from May to September 2010, peaking in late November 2010, and strongly decreasing in the subsequent years. The peak in hydrocarbon concentrations were corroborated by higher organic carbon contents, more depleted Δ14C values and biomarker ratios similar to those of the initial MC252 crude oil reported in the literature. These results indicate that at least part of oil discharged from the accident sedimented to the seafloor in subsequent months, resulting in an apparent accumulation of hydrocarbons on the seabed by the end of 2010. Sediment resuspension and transport or biodegradation may account for the decrease in sedimented oil quantities in the years following the Macondo well spill.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos/análise , Poluição por Petróleo/análise , Poluentes Químicos da Água/análise , Alcanos/metabolismo , Biodegradação Ambiental , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Golfo do México , Petróleo/análise
2.
Rev. bras. farmacogn ; 24(2): 103-109, Mar-Apr/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-714764

RESUMO

This work compiled Brazilian articles regarding medicinal plant use by local communities in order to analyze the most common sampling problems and if research characteristics can influence the presence of sampling irregularities. We focused on studies about medicinal plants that present a species-indications list and had a quantitative nature. The proportion of works with and without sampling problems was evaluated considering the journal impact factor, period of publication, community status (urban x rural), sample type, presence of testing hypothesis and presence of research questions. We found that an alarming proportion of papers had some kind of sampling problems (48.39% serious and 19.35% moderate). The most common problems were related to: lack of information regarding the sample size or the universe, small sample sizes and selection of specialists based on obscure criteria. We could not find a significant influence between our tested variables and the occurrence of sampling problems, except for the community status (urban x rural). Results indicate that a significant amount of intracultural diversity is not properly captured, taking into consideration both the population as a whole and a group of interest in the community (= healers).

3.
Rev. bras. cir. cardiovasc ; Rev. bras. cir. cardiovasc;24(4): 447-452, out.-dez. 2009. ilus
Artigo em Inglês, Português | LILACS | ID: lil-540745

RESUMO

Objetivo: Avaliar o resultado imediato da operação de Norwood modificado com nova técnica de perfusão regional cerebral (PRCeA) anterógrada associado a perfusão regional coronariana (PRCoR) retrógrada em substituição à parada circulatória total com hipotermia profunda em crianças portadoras da Síndrome da Hipoplasia do Coração Esquerdo (SHCE) com aorta ascendente extremamente hipoplásica (AH). Métodos: No período de dezembro de 2006 a fevereiro de 2008, a operação de Norwood modificado com tubo entre o ventrículo direito e as artérias pulmonares ou shunt tipo Sano foi realizada em oito crianças portadoras de SHCE e aorta ascendente com diâmetro inferior a 3 mm, (quatro do sexo masculino e quatro do sexo feminino) com idade média de 9,2 dias (variando de 1 a 29 dias) e peso médio de 3,3 kg (variando de 2,7 a 3,8 kg). Utilizada CEC e hipotermia a 25ºC com duas cânulas venosas e anastomose de um enxerto de politetrafluoretileno com a artéria inominada utilizado como linha arterial e para PRCeA. A PRCoR foi realizada por meio de um desvio na linha arterial e colocação de um cateter na aorta ascendente. Foram analisados o resultado cirúrgico imediato e a presença de alterações neurológicas nesse período. Resultados: O resultado cirúrgico imediato revelou mortalidade de 25 por cento e ausência de comprometimento neurológico ao exame clínico. Conclusão: A operação de Norwood modificado pode ser realizada com PRCeA e PRCoR em crianças com SHCE e AH com resultado cirúrgico imediato satisfatório e ausência de complicações neurológicas.


Objective: To assess the immediate result of the modified Norwood procedure with new technique of anterograde regional cerebral perfusion (ARCeP) and retrograde regional coronary perfusion (RRCoP) in substitution of profound hypothermia and circulatory arrest in children with hypoplastic left heart syndrome (HLHS) with extremely hypoplastic ascending aorta (HA). Methods: In the period of December of 2006 to February 2008 the modified Norwood procedure with tube between the right ventricle and pulmonary arteries or Sano shunt was performed in eight children with HLHS and with ascending aorta diameter less than 3 mm, (four male and four female) with median age of 9.2 days (ranging from 1 to 29 days) and median weigh of 3.3 kg (ranging from 2.7 to 3.8 kg). We used cardiopulmonary bypass and hypothermia at 25ºC with two venous cannulas and suture with a polytetrafluoroethylene graft sutured to the innominate artery as an arterial line and used to ARCeP. The RRCoP was performed by a deviation in the arterial line and placement of a catheter in the ascending aorta. The immediate surgical results and the clinical neurological manifestation were assessed. Results: The immediate surgical results revealed mortality of 25 percent and there were absence of neurological injury at clinical examination. Conclusions: The modified Norwood procedure can be accomplished with ARCeP and RRCoP in children with HLHS with HA with satisfactory immediate surgical result and without neurological complications.


Assuntos
Feminino , Humanos , Recém-Nascido , Masculino , Aorta/cirurgia , Circulação Cerebrovascular , Circulação Coronária , Procedimentos Cirúrgicos Cardíacos/métodos , Ponte Cardiopulmonar/métodos , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Anastomose Cirúrgica/métodos , Aorta/anormalidades , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Ponte Cardiopulmonar/instrumentação , Síndrome do Coração Esquerdo Hipoplásico/mortalidade , Resultado do Tratamento
4.
Rev Bras Cir Cardiovasc ; 24(4): 447-52, 2009.
Artigo em Inglês, Português | MEDLINE | ID: mdl-20305916

RESUMO

OBJECTIVE: To assess the immediate result of the modified Norwood procedure with new technique of anterograde regional cerebral perfusion (ARCeP) and retrograde regional coronary perfusion (RRCoP) in substitution of profound hypothermia and circulatory arrest in children with hypoplastic left heart syndrome (HLHS) with extremely hypoplastic ascending aorta (HA). METHODS: In the period of December of 2006 to February 2008 the modified Norwood procedure with tube between the right ventricle and pulmonary arteries or Sano shunt was performed in eight children with HLHS and with ascending aorta diameter less than 3 mm, (four male and four female) with median age of 9.2 days (ranging from 1 to 29 days) and median weigh of 3.3 kg (ranging from 2.7 to 3.8 kg). We used cardiopulmonary bypass and hypothermia at 25 masculineC with two venous cannulas and suture with a polytetrafluoroethylene graft sutured to the innominate artery as an arterial line and used to ARCeP. The RRCoP was performed by a deviation in the arterial line and placement of a catheter in the ascending aorta. The immediate surgical results and the clinical neurological manifestation were assessed. RESULTS: The immediate surgical results revealed mortality of 25% and there were absence of neurological injury at clinical examination. CONCLUSIONS: The modified Norwood procedure can be accomplished with ARCeP and RRCoP in children with HLHS with HA with satisfactory immediate surgical result and without neurological complications.


Assuntos
Aorta/cirurgia , Procedimentos Cirúrgicos Cardíacos/métodos , Ponte Cardiopulmonar/métodos , Circulação Cerebrovascular , Circulação Coronária , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Anastomose Cirúrgica/métodos , Aorta/anormalidades , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Ponte Cardiopulmonar/instrumentação , Feminino , Humanos , Síndrome do Coração Esquerdo Hipoplásico/mortalidade , Recém-Nascido , Masculino , Resultado do Tratamento
5.
Environ Sci Technol ; 39(18): 6961-70, 2005 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16201617

RESUMO

Despite all of the economic problems and environmental discussions on the dangers and hazards of plastic materials, plastic production worldwide is growing at a rate of about 5% per year. Increasing techniques for recycling polymeric materials have been developed during the last few years; however, a large fraction of plastics are still being discarded in landfills or subjected to intentional or incidental open-fire burning. To identify specific tracer compounds generated during such open-fire combustion, both smoke particles from burning and plastic materials from shopping bags, roadside trash, and landfill garbage were extracted for gas chromatography-mass spectrometry analyses. Samples were collected in Concón, Chile, an area frequently affected by wildfire incidents and garbage burning, and the United States for comparison. Atmospheric samples from various aerosol sampling programs are also presented as supportive data. The major components of plastic extracts were even-carbon-chain n-alkanes (C16-C40), the plasticizer di-2-ethylhexyl phthalate, and the antioxidants and lubricants/antiadhesives Irganox 1076, Irgafos 168, and its oxidation product tris(2,4-di-tertbutylphenyl) phosphate. Major compounds in smoke from burning plastics include the non-source-specific n-alkanes (mainly even predominance), terephthalic acid, phthalates, and 4-hydroxybenzoic acid, with minor amounts of polycyclic aromatic hydrocarbons (including triphenylbenzenes) and tris(2,4-di-tert-butylphenyl)phosphate. 1,3,5-Triphenylbenzene and tris(2,4-di-tert-butylphenyl)- phosphate were found in detectable amounts in atmospheric samples where plastics and refuse were burned in open fires, and thus we propose these two compounds as specific tracers for the open-burning of plastics.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Compostos Orgânicos/análise , Plásticos/análise , Eliminação de Resíduos , Aerossóis , Antioxidantes/análise , Atmosfera , Benzeno/análise , Hidroxitolueno Butilado/análogos & derivados , Hidroxitolueno Butilado/análise , Carbono/química , Chile , Dietilexilftalato/análise , Resíduos de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Modelos Químicos , Organofosfatos/análise , Fosfitos/análise , Plastificantes , Hidrocarbonetos Policíclicos Aromáticos , Polímeros/química , Polipropilenos , Fumaça , Fatores de Tempo , Estados Unidos
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