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1.
Nat Clim Chang ; 11(6): 492-500, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34221128

RESUMEN

Climate change affects human health; however, there have been no large-scale, systematic efforts to quantify the heat-related human health impacts that have already occurred due to climate change. Here, we use empirical data from 732 locations in 43 countries to estimate the mortality burdens associated with the additional heat exposure that has resulted from recent human-induced warming, during the period 1991-2018. Across all study countries, we find that 37.0% (range 20.5-76.3%) of warm-season heat-related deaths can be attributed to anthropogenic climate change and that increased mortality is evident on every continent. Burdens varied geographically but were of the order of dozens to hundreds of deaths per year in many locations. Our findings support the urgent need for more ambitious mitigation and adaptation strategies to minimize the public health impacts of climate change.

2.
Indoor Air ; 26(4): 526-37, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26182845

RESUMEN

Indoor air quality (IAQ) parameters in 73 primary classrooms in Porto were examined for the purpose of assessing levels of volatile organic compounds (VOCs), aldehydes, particulate matter, ventilation rates and bioaerosols within and between schools, and potential sources. Levels of VOCs, aldehydes, PM2.5 , PM10 , bacteria and fungi, carbon dioxide (CO2 ), carbon monoxide, temperature and relative humidity were measured indoors and outdoors and a walkthrough survey was performed concurrently. Ventilation rates were derived from CO2 and occupancy data. Concentrations of CO2 exceeding 1000 ppm were often encountered, indicating poor ventilation. Most VOCs had low concentrations (median of individual species <5 µg/m(3) ) and were below the respective WHO guidelines. Concentrations of particulate matter and culturable bacteria were frequently higher than guidelines/reference values. The variability of VOCs, aldehydes, bioaerosol concentrations, and CO2 levels between schools exceeded the variability within schools. These findings indicate that IAQ problems may persist in classrooms where pollutant sources exist and classrooms are poorly ventilated; source control strategies (related to building location, occupant behavior, maintenance/cleaning activities) are deemed to be the most reliable for the prevention of adverse health consequences in children in schools.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Instituciones Académicas/estadística & datos numéricos , Ventilación/estadística & datos numéricos , Aerosoles/análisis , Aldehídos/análisis , Dióxido de Carbono/análisis , Niño , Humanos , Material Particulado/análisis , Portugal , Ventilación/métodos , Compuestos Orgánicos Volátiles/análisis
3.
Allergy ; 71(2): 175-88, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26476125

RESUMEN

We aimed to assess the value and classification rate of exhaled volatile organic compounds (VOCs) in asthma diagnosis. A PRISMA-oriented systematic search for published studies regarding exhaled VOCs in asthma diagnosis was conducted based on predefined criteria. Studies presenting sensitivity and specificity values for the test were included in the meta-analysis. Pooled diagnosis odds ratios (DOR), area under the curve (AUC) and positive and negative likelihood ratios (LR) for exhaled VOC profiles were calculated; and publication bias, threshold effect and heterogeneity were estimated. Eighteen studies were selected for the qualitative analysis and six met the criteria for inclusion in the quantitative analysis. Mean (95% CI) pooled DOR, positive and negative LR were 49.3 (15.9-153.3), 5.86 (3.07-11.21) and 0.16 (0.10-0.26), respectively. The AUC value was 0.94. Only three of the 18 reviewed studies performed an external validation of the model using a different data set. The results from the revised studies suggest that exhaled VOCs are promising biomarkers for asthma diagnosis and that several compounds, mainly alkanes, may be significantly associated with asthma inflammation. However, there are still various constraints associated with standardization and externally validated studies are needed to introduce exhaled VOC profiling in a clinical scenario.


Asunto(s)
Asma/diagnóstico , Asma/metabolismo , Biomarcadores , Compuestos Orgánicos Volátiles , Diagnóstico Diferencial , Espiración , Humanos , Oportunidad Relativa , Sesgo de Publicación , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad
4.
Water Sci Technol ; 67(2): 374-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23168638

RESUMEN

A preliminary study of the gamma radiation effects on the antioxidant compounds present in cork cooking water was carried out. Radiation studies were performed using radiation between 20 and 50 kGy at 0.4 and 2.4 kGy h(-1). The radiation effects on organic matter content were evaluated by chemical oxygen demand. The antioxidant activity was measured by ferric reducing power assay. The total phenolic content was studied using the Folin-Ciocalteau method. Results show that gamma radiation increases both the amount of phenolic compounds and antioxidant capacity of cork cooking water. These results highlight the potential of this technology for increasing the added value of cork waters.


Asunto(s)
Antioxidantes/efectos de la radiación , Residuos Industriales/análisis , Corteza de la Planta/química , Radiación Ionizante , Aguas Residuales/química , Adsorción , Análisis de la Demanda Biológica de Oxígeno , Recuperación de Fluorescencia tras Fotoblanqueo , Fenoles/análisis
5.
Arq. bras. med. vet. zootec ; 57(5): 697-701, out. 2005. tab
Artículo en Portugués | LILACS | ID: lil-418852

RESUMEN

Pesquisaram-se eventuais diferencas na composicão da matéria seca (MS), proteína bruta, extrato etéreo, cinzas, cálcio, fósforo, cobre, zinco, perfil de aminoácidos e biotina entre cascos pretos e claros, de eqüinos das racas Pantaneira e Mangalarga Marchador, criados na região do Pantanal, MS, e no município de Caeté, MG, respectivamente. De cada raca foram coletadas amostras de 10 éguas vazias, não lactantes, com idade entre 5 e 10 anos, sendo que, em um mesmo animal, foram retiradas amostras das duas coloracões de casco nas regiões da pinca, ombro, quarto e talão. Na raca Pantaneira, os cascos claros apresentaram maior teor de fósforo que os pretos, e os demais elementos avaliados não foram diferentes segundo a cor. Na Mangalarga Marchador, não houve diferenca entre os cascos claros e pretos, quanto a todas as características estudadas.


Asunto(s)
Pezuñas y Garras/química , Caballos
6.
J Mass Spectrom ; 36(5): 529-37, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11391809

RESUMEN

Electrospray ionization mass spectrometry (ESIMS) was used to characterize a series of new ruthenium(II) complexes with several nitrogen heterocycles and a common ligand: the crown thioether 1,4,7-trithiacyclononane, [9]aneS(3). ESIMS allows the easy identification of the [Ru(II)Cl([9]aneS(3))Y]X complexes, where Y is a bidentate nitrogen heterocycle and X is Cl(-) or PF(6)(-), through the formation of two diagnostic ions by fragmentation of the common ligand [9]aneS(3). Structures for these ions and mechanisms for their gas-phase formation are proposed based on data from product ion spectra.


Asunto(s)
Éteres Cíclicos/química , Compuestos Heterocíclicos/química , Compuestos de Rutenio/química , Espectrometría de Masa por Ionización de Electrospray , Sulfuros/química
7.
Met Based Drugs ; 8(3): 125-36, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-18475986

RESUMEN

The complexes [Ru([9]aneS(3))(dppz)Cl]Cl 1 and [Ru([12]aneS(4))(dppz)]Cl(2)2 ([9]aneS(3) = 1,4,7- trithiaciclononane and [12]aneS(4) = 1,4,7,10-tetrathiaciclododecane) were synthesised and fully characterised. These complexes belong to a small family of dipyridophenazine complexes with non-polypyridyl ancillary ligands . Interaction studies of these complexes with CT-DNA (UV/Vis titrations, steady-state emission and thermal denaturation) revealed their high affinity for DNA . Intercalation constants determined by UV/Vis titrations are of the same order of magnitude (10(6)) as other dppz metallointercalators, namely [Ru(II)(bpy)(2)dppz]S(2+). Differences between l and2 were identified by steady-state emission and thermal denaturation studies . Emission results are in accordance with structural data, which indicate how geometric distortions and different donor and/or acceptor ligand abilities affect luminescence. The possibility of noncovalent interactions between ancillary ligands and nucleobases by van der Waals contacts and H-bridges is discussed . Furthermore, complex l undergoes aquation under intra-cellular conditions and an equilibrium with the aquated form l' is attained . This behaviour may increase the diversity of available interaction modes.

8.
Arq. bras. med. vet. zootec ; 52(2): 98-104, abr. 2000. tab
Artículo en Portugués | LILACS | ID: lil-261117

RESUMEN

Em um esquema de parcela subdividida que incluía dois tratamentos (A= solo arenoso e B= solo argiloso) e 10 subtratamentos (10 épocas de amostragem) a bioquímica clínica de 20 vacas de corte, sob pastejo contínuo de B. decumbens, foi acompanhada durante 13 meses. Os constituintes sangüíneos estudados foram: glicose (GLI), hemoglobina (HB), bilirrubina (BIL), creatinina (CREA), albumina (ALB), aspartatoaminotransferase (AST), fosfatase alcalina (FAS) e creatinoquinase (CK). Foram obtidos valores médios de 98,0 e 110,2 mg/dl para GLI, 13,27 e 13,38g/l para HB, 0,718 e 0,661mg/dl para BIL, 1,89 e 1,73mg/dl para CREA e 3,56 e 3,39g/dl para ALB nos tratamentos A e B, respectivamente. Vacas aneloradas apresentaram um perfil bioquímico clínico de animais aparentemente sadios, isto é, ausência de anemia, icterícia e disfunçäo renal. Näo foi possível diagnosticar alteraçöes hepáticas mas ocorreram lesöes musculares (CK) em algumas épocas, sem afetar clinicamente os animais. GLI, ALB, AST e FAS apresentaram mudança sazonal com níveis mais altos na primavera-veräo e mais baixos no período de seca, no outono-inverno


Asunto(s)
Animales , Femenino , Albúminas , Bioquímica , Creatinina , Enzimas
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