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1.
J Allergy Clin Immunol ; 128(2): 284-292.e7, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21536321

RESUMEN

BACKGROUND: Asthma prevalence varies widely among neighborhoods within New York City. Exposure to mouse and cockroach allergens has been suggested as a cause. OBJECTIVE: To test the hypotheses that children living in high asthma prevalence neighborhoods (HAPNs) would have higher concentrations of cockroach and mouse allergens in their homes than children in low asthma prevalence neighborhoods (LAPNs), and that these exposures would be related to sensitization and asthma. METHODS: In the New York City Neighborhood Asthma and Allergy Study, a case-control study of asthma, children 7 to 8 years old from HAPNs (n = 120) and LAPNs (n = 119) were recruited through the same middle-income health insurance plan. Children were classified as asthma cases (n = 128) or controls without asthma (n = 111) on the basis of reported symptoms or medication use. Allergens were measured in bed dust. RESULTS: HAPN homes had higher Bla g 2 (P = .001), Mus m 1 (P = .003), and Fel d 1 (P = .003) and lower Der f 1 (P = .001) than LAPN homes. Sensitization to indoor allergens was associated with asthma, but relevant allergens differed between LAPNs and HAPNs. Sensitization to cockroach was more common among HAPN than LAPN children (23.7% vs 10.8%; P = .011). Increasing allergen exposure was associated with increased probability of sensitization (IgE) to cockroach (P < .001), dust mite (P = .009), and cat (P = .001), but not mouse (P = .58) or dog (P = .85). CONCLUSION: These findings further demonstrate the relevance of exposure and sensitization to cockroach and mouse in an urban community and suggest that cockroach allergen exposure could contribute to the higher asthma prevalence observed in some compared with other New York City neighborhoods.


Asunto(s)
Alérgenos/inmunología , Asma/epidemiología , Exposición a Riesgos Ambientales , Hipersensibilidad Inmediata/epidemiología , Características de la Residencia , Población Urbana , Alérgenos/efectos adversos , Animales , Asma/diagnóstico , Asma/fisiopatología , Estudios de Casos y Controles , Gatos/inmunología , Niño , Cucarachas/inmunología , Perros/inmunología , Polvo/análisis , Polvo/inmunología , Femenino , Humanos , Hipersensibilidad Inmediata/diagnóstico , Hipersensibilidad Inmediata/etiología , Hipersensibilidad Inmediata/inmunología , Inmunoglobulina E/sangre , Masculino , Ratones/inmunología , Ciudad de Nueva York , Poaceae/inmunología
2.
Rev. colomb. quím. (Bogotá) ; 48(3): 26-35, sep.-dic. 2019. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1058425

RESUMEN

Abstract Every year the demand for energy worldwide is increasing. There are some alternatives to reduce these problems, such as clean energy or renewable energy. A particular alternative is the microbial fuel cells. These cells are biochemical reactors that convert chemical energy into electricity. The present research evaluated the dairy serum to produce bioelectricity from micro fuel cells (MFC) that were constructed with low-cost materials and with isolated bacteria in anaerobic sediments, located in Ecuadorian national territory, producing maximum voltages of 0.830 V in the circuit and a maximum power density of 30 mW / m2. This low voltage was worked with 50 mL MFCs and with an output voltage of 300 mV. Under these conditions, a FLYBACK lift circuit isolated by the transformer was designed. This new circuit could increase the voltage from 30 mV to enough voltage to light a 2.5 V LED. Therefore, the energy produced by the MFC can be directly used to light a LED and to charge capacitors. This study shows that these MFCs, together with the designed circuit, could be used potentially to generate clean energy.


Resumen Cada año la demanda de energía, en todo el mundo, va en aumento. Existen algunas alternativas para reducir estos problemas, tales como las energías limpias y renovables. Una alternativa muy específica es el uso de celdas de combustible microbianas. Dichas celdas son reactores bioquímicos que convierten la energía química en electricidad. La presente investigación evaluó el suero lácteo para la producción de bioelectricidad en celdas de combustible microbianas (MFC). Estas fueron construidas con materiales de bajo costo y con bacterias aisladas en sedimentos anaeróbicos, ubicados en territorio nacional ecuatoriano, produciendo voltajes máximos de 0,830 V en el circuito y una densidad de potencia máxima de 30 mW / m2. Este bajo voltaje se trabajó con MFC de 50 mL y con un voltaje de salida de 300 mV. Bajo estas condiciones, se diseñó un circuito de elevación FLYBACK aislado por transformador. Este nuevo circuito aumentará el voltaje de 30 mV a un voltaje suficiente para encender un LED de 2.5 V. Por lo tanto, la energía producida por las MFC puede ser directamente utilizable para encender un LED y cargar los condensadores. Este estudio muestra que dichas celdas MFC, junto con el circuito diseñado, podrían utilizarse, potencialmente, para generar energía limpia.


Resumo Todos os anos a demanda por energia, em todo o mundo, está aumentando. Existem algumas alternativas para reduzir esses problemas, como energias limpas e renováveis. Uma alternativa muito específica é o uso de células combustíveis microbianas. Essas células são reatores bioquímicos que convertem energia química em eletricidade. O presente trabalho avaliou o soro lácteo para a produção de bioeletricidade em células a combustível microbianas (CCM), Estes foram construídos com materiais de baixo custo e bactérias isoladas em sedimentos anaeróbios, localizados no território nacional equatoriano, produzindo tensões máximas de 0,830 V no circuito e uma densidade de potência máxima de 30 mW / m2. Esta baixa voltagem trabalhamos com CCM de 50 mL e com uma voltagem de saída de 300 mV. Sob essas condições, um circuito de elevação FLYBACK isolado por transformador foi projetado. Este novo circuito aumentará a tensão de 30 mV para uma tensão suficiente para ligar um LED de 2,5 V. Portanto, a energia produzida pelo MFC pode ser diretamente utilizável para ligar um LED e carregar os capacitores. Este estudo mostra que essas células CCM, juntamente com o circuito projetado, poderiam ser usadas para gerar energia limpa.

3.
Pediatrics ; 131(1): e127-35, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23248227

RESUMEN

OBJECTIVE: Exercise-induced wheeze (EIW) may identify a distinct population among asthmatics and give insight into asthma morbidity etiology. The prevalence of pediatric asthma and associated urgent medical visits varies greatly by neighborhood in New York City and is highest in low-income neighborhoods. Although increased asthma severity might contribute to the disparities in urgent medical visits, when controlling for health insurance coverage, we previously observed no differences in clinical measures of severity between asthmatic children living in neighborhoods with lower (3%-9%) versus higher (11%-19%) asthma prevalence. Among these asthmatics, we hypothesized that EIW would be associated with urgent medical visits and a child's neighborhood asthma prevalence. METHODS: Families of 7- to 8-year-old children were recruited into a case-control study of asthma through an employer-based health insurance provider. Among the asthmatics (n = 195), prevalence ratios (PRs) for EIW were estimated. Final models included children with valid measures of lung function, seroatopy, and waist circumference (n = 140). RESULTS: EIW was associated with urgent medical visits for asthma (PR, 2.29; P = .021), independent of frequent wheeze symptoms. In contrast to frequent wheeze, EIW was not associated with seroatopy or exhaled NO, suggesting a distinct mechanism. EIW prevalence among asthmatics increased with increasing neighborhood asthma prevalence (PR, 1.09; P = .012), after adjustment for race, ethnicity, maternal asthma, environmental tobacco smoke, household income, and neighborhood income. CONCLUSIONS: EIW may contribute to the disparities in urgent medical visits for asthma between high- and low-income neighborhoods. Physicians caring for asthmatics should consider EIW an indicator of risk for urgent medical visits.


Asunto(s)
Atención Ambulatoria , Asma Inducida por Ejercicio/diagnóstico , Asma Inducida por Ejercicio/epidemiología , Ejercicio Físico/fisiología , Características de la Residencia , Ruidos Respiratorios/diagnóstico , Atención Ambulatoria/métodos , Asma/diagnóstico , Asma/epidemiología , Asma/terapia , Asma Inducida por Ejercicio/terapia , Estudios de Casos y Controles , Niño , Femenino , Humanos , Masculino , Ciudad de Nueva York/epidemiología , Prevalencia , Ruidos Respiratorios/fisiología
4.
J Expo Sci Environ Epidemiol ; 22(3): 258-66, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22377682

RESUMEN

Differential exposure to combustion by-products and allergens may partially explain the marked disparity in asthma prevalence (3-18%) among New York City neighborhoods. Subclinical changes in airway inflammation can be measured by fractional exhaled nitric oxide (FeNO). FeNO could be used to test independent effects of these environmental exposures on airway inflammation. Seven- and eight-year-old children from neighborhoods with lower (range 3-9%, n=119) and higher (range 11-18%, n=121) asthma prevalence participated in an asthma case-control study. During home visits, FeNO was measured, and samples of bed dust (allergens) and air (black carbon; BC) were collected. Neighborhood built-environment characteristics were assessed for the 500 m surrounding participants' homes. Airborne BC concentrations in homes correlated with neighborhood asthma prevalence (P<0.001) and neighborhood densities of truck routes (P<0.001) and buildings burning residual oil (P<0.001). FeNO concentrations were higher among asthmatics with than in those without frequent wheeze (≥4 times/year) (P=0.002). FeNO concentrations correlated with domestic BC among children without seroatopy (P=0.012) and with dust mite allergen among children with seroatopy (P=0.020). The association between airborne BC in homes and both neighborhood asthma prevalence and FeNO suggest that further public health interventions on truck emissions standards and residual oil use are warranted.


Asunto(s)
Contaminantes Atmosféricos , Pruebas Respiratorias , Carbono , Óxido Nítrico/análisis , Alérgenos , Asma/epidemiología , Niño , Exposición a Riesgos Ambientales , Femenino , Humanos , Inmunoglobulina E/sangre , Masculino , Ciudad de Nueva York/epidemiología , Prevalencia
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