963 resultados para Blood carbon monoxide levels.


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Experiments of biomass combustion were performed to determine whether specimen size, tray inclination, or combustion air flow rate was the factor that most affects the emission of carbon dioxide, carbon monoxide, and methane. The chosen biomass was Eucalyptus citriodora, a very abundant species in Brazil, utilized in many industrial applications, including combustion for energy generation. Analyses by gas chromatograph and specific online instruments were used to determine the concentrations of the main emitted gases, and the following figures were found for the emission factors: 1400 ± 101 g kg-1 of CO2, 50 ± 13 g kg-1 of CO, and 3.2 ± 0.5 g kg-1 of CH4, which agree with values published in the literature for biomass from the Amazon rainforest. Statistical analysis of the experiments determined that specimen size most significantly affected the emission of gases, especially CO2 and CO. •Statistical analysis to determine effects on emission factors.•CO2, CO, CH4 emission factors determined for combustion of Eucalyptus.•Laboratory results agreed with data for Amazonian biomass combustion in field tests.•Combustion behavior under flaming and smoldering was analyzed. © 2013 Elsevier Ltd.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

As estratégias atuais de combate à malária estimulam o conhecimento mais profundo dos mecanismos de defesa humana antiplasmodiais. A cooperação de anticorpos citofilicos com monócitos sangüíneos facilitando a fagocitose de células infectadas, tem mostrado ser um mecanismo efetivo nesta defesa. Estudos comparativos entre populações semi-imunes e não imunes têm sido feitos a fim de identificar o padrão de imunoglobulinas nestas populações. Somando-se a estes, o presente trabalho objetivou avaliar a resposta de anticorpos IgG anti-P.vivax (lgG anti-PV), subclasses citofilicas: IgG1 e IgG3 e não citofilicas: IgG2, em crianças com malária por P.vivax. Foram avaliadas 34 crianças portadoras de malária vivax, diagnosticadas pela gota espessa, acompanhadas desde a fase aguda até o último controle de cura, as quais tiveram seus níveis de anticorpos IgG anti-PV e subclasses mensurados pela técnica de imunoflüorescência indireta. Os pacientes foram subdivididos em dois grupos: priminfectados (n=28) e pacientes com história de malária anterior o (n=6). A média geométrica dos títulos de anticorpos IgG anti-PV, foi o demonstrada nos diferentes períodos relativos ao controle de cura, sendo que o os níveis de anticorpos mensurados durante a fase aguda (dias zero e sete) foram comparados (teste t de Student). Níveis de anticorpos IgG anti-PV foram correlacionados com parasitemia e tempo de doença, (Correlação de Spearman). Sinais e sintomas clínicos foram descritos em ambos subgrupos. A proporção de indivíduos positivos e negativos quanto as subclasses foi comparada nos dois subgrupos (teste exato de Fisher). Os resultados mostraram um aumento inicial dos títulos de IgG anti-PV entre o dia zero (D0) e o dia sete (D7), sendo esta diferença significativa (p=0,027), independente de exposição anterior ou não à malária. Aos 60, 120 e 180 dias pós-tratamento, obteve-se uma curva descendente de títulos, com as seguintes proporções de respostas positivas: aos 60 dias: 95,2%, com títulos variando entre 40 e 2560; aos 120 dias: 62,5%, com variação de 40 e 320; e aos 180 dias apenas 28,5% de positivos, com variação entre 40 e 160. Foi encontrada correlação positiva entre tempo de doença e níveis de anticorpos totais entre indivíduos priminfectados. As médias geométricas dos títulos de anticorpos IgG anti-PV subclasses encontradas em D0 foram: IgG1 (598,41) > IgG3 (4,064) > IgG2 (1,422). Não ocorreram diferenças entre proporções de indivíduos positivos e negativos para as subclasses de IgG anti-PV, quando se comparou priminfectados e pacientes sem história anterior de malária. Concluiu-se que, no grupo estudado: 1) Ocorre inicialmente aumento de anticorpos IgG anti-PV entre o primeiro e oitavo dia de tratamento; 2) Os níveis de anticorpos totais anti-PV declinam gradativamente durante o controle de cura: 4,76% dos pacientes apresentaram resultados negativos até D60, 37,5% até D120, e 71,42% até 180 dias após o início do tratamento 3) Não há associação entre parasitemia assexuada no dia zero e títulos de anticorpos IgG anti-PV no primeiro e oitavo dias de tratamento; 4) Em crianças expostas a ataques anteriores, quanto maior o tempo de evolução da doença, maiores são os níveis de anticorpos, ao contrário do que ocorreu com crianças priminfectadas; 5) Não há correlação entre títulos de anticorpos anti-PV totais e presença de esplenomegalia; 6) Houve predominância de anticorpos citofilicos (lgG1 > IgG3), sobre os anticorpos não citofilicos, na amostra estudada.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This study tested whether 3-4 weeks of classical Live High-Train High (LHTH) altitude training increases swim-specific VO2max through increased hemoglobin mass (Hb(mass)).Ten swimmers lived and trained for more than 3 weeks between 2,130 and 3,094 m of altitude, and a control group of ten swimmers followed the same training at sea-level (SL). Body composition was examined using dual X-ray absorptiometry. Hb(mass) was determined by carbon monoxide rebreathing. Swimming VO2peak was determined and swimming trials of 4 x 50, 200 and 3,000 m were performed before and after the intervention.Hb(mass) (n = 10) was increased (P < 0.05)after altitude training by 6.2 +/- A 3.9 % in the LHTH group, whereas no changes were apparent in the SL group (n = 10). Swimming VO2peak was similar before and after training camps in both groups (LHTH: n = 7, SL: n = 6). Performance of 4 x 50 m at race pace was improved to a similar degree in both groups (LHTH: n = 10, SL: n = 10). Maximal speed reached in an incremental swimming step test (P = 0.051), and time to complete 3,000 m tended (P = 0.09) to be more improved after LHTH (n = 10) than SL training (n = 10).In conclusion, 3-4 weeks of classical LHTH is sufficient to increase Hb(mass) but exerts no effect on swimming-specific VO2peak. LHTH may improve performance more than SL training.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Using density functional theory and a model developed in our own group, we have investigated the suitability of three intermetallic compounds - AuSn, PdSn, and PtSn - as electrode materials for hydrogen oxidation in fuel cells, focusing on their CO tolerance and their catalytic properties. All three metals were found to have lower susceptibility to be poisoned by CO compared to platinum, but only PtSn promises to be a good catalyst for hydrogen oxidation. (C) 2013 Elsevier Ltd. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The performance and emissions behavior of a Rover 1S/60 turboshaft engine when operated with several blends of aviation kerosene and ox tallow ethyl-ester are shown in this article. The tests were performed with a compressor shaft coupled to an hydraulic dynamometer where data of power and mass fuel flow were collected to determine the brake specific fuel consumption. A flue gas analyzer was positioned at the exhaust duct to collect oxygen, carbon dioxide, carbon monoxide and nitrous oxides. An increase in the specific fuel consumption was observed due to the lesser lower heating value of the most oxygenated blends. However, reductions of CO, CO2 and NO (x) have been observed and no-significant ill effects have occurred in the turbine operation.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Objectives: This experimental study aimed to evaluate the effects of central catalase inhibition on cardiovascular responses in rats exposed to sidestream cigarette smoke (SSCS) for 3 weeks. Methodology: A total of 20 males Wistar rats (320–370g) were implanted with a stainless steel guide cannula into the fourth cerebral ventricle (4thV). Femoral artery and vein were cannulated for mean arterial pressure (MAP) and heart rate (HR) measurement and drug infusion, respectively. Rats were exposed to SSCS for three weeks, 180 minutes per day, 5 days/week [carbon monoxide (CO): 100–300 ppm)]. Baroreflex was tested with one pressor dose of phenylephrine (PHE, 8 μg/kg, bolus) and one depressor dose of sodium nitroprusside (SNP, 50 μg/kg, bolus). Cardiovascular responses were evaluated before and 15 minutes after 3-amino-1, 2, 4-triazole (ATZ, catalase inhibitor, 0.001g/100μL) injection into the 4th V. Results: Vehicle treatment into the 4th V did not change cardiovascular responses. Central catalase inhibition increased tachycardic peak, attenuated bradycardic peak and reduced HR range at 15 minutes, increased MAP at 5, 15 and 30 min and increased HR at 5 and 15 min. In rats exposed to SSCS, central ATZ increased basal MAP after 5 min and increased HR at 5, 15 and 30 minutes, respectively, and attenuated bradycardic peak at 15 minutes. Conclusion: This study suggests that brain oxidative stress caused by SSCS influences autonomic regulation of the cardiovascular system.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In this work we investigate the dissociation of heteronuclear diatomic molecules subjected to laser pulses. This phenomenon can be modeled by the classical forced Morse oscillator. This system presents a chaotic dynamics associated with the anharmonicity of the internuclear potential and with the coupling of permanent dipole of molecule with the electric field of laser. We want to verify how the dissociation probability evolves while we change the intensity and frequency of laser. We study the phase space of molecules to have a better understanding of system dynamics. We make the calculations changing two parameters of laser (intensity and frequency) and checking how this parameters influences on molecule dissociation. We compare the results of HF molecule (Fluoride acid) and CO molecule (Carbon monoxide) to check how the dipole moment of each molecule can influence on laser interaction

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Aiming to reduce the cost of electrocatalysts and a greater resistance to CO poisoning this work was to study the adsorption and oxidation of carbon monoxide on ordered intermetallic phases AuIn, AuSb2, AuSn, PdSb and PdSn using voltammetric techniques in alkaline electrolyte solution. The results suggest that the AuSn and PdSn intermetallics has some form of resistance to CO poisoning. It is assumed that this behavior is a result of electronic effect and the effect of the third body has been achieved by adding a second metal to Au and Pd. However, further studies should be conducted to confirm this hypothesis as to test these materials as electrocatalysts in the reaction of oxidation of fuels

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper proposes an analysis of two major polluting elements of the atmosphere of São Paulo city, carbon monoxide (CO) and sulfur dioxide (SO2). This study was performed through analysis of data on the quality of air, by means of published reports and records obtained by experiment using measuring rate monitor for CO2. Atmospheric data were collected and sorted. From this work it was possible to identify the concentration of carbon dioxide in the center of São Paulo on September 14, 2012 using the infrared gas analyzer (IRGA). From the ratios of carbon monoxide and sulfur dioxide spatially analyzed could identify major emitters by comparing records of pollutants and their origin. The analysis makes it possible to map the intensity of air pollution in urban areas, identifying the polluting elements, their issuers and thereby contributes to the current understanding of atmospheric features, bringing a geographical spatial analysis of air pollutants in São Paulo, contributing to awareness of vulnerabilities, enabling a useful tool for planning and maintenance of the urban environment related public policies