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4.
Pers Soc Psychol Bull ; 42(7): 855-63, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27149876

RESUMO

People drastically overestimate how often others attend to them or notice their unusual features, a phenomenon termed the spotlight effect Despite the prevalence of this egocentric bias, little is known about how to reduce the tendency to see oneself as the object of others' attention. Here, we tested the hypothesis that a basic property of mental imagery-the visual perspective from which an event is viewed-may alleviate a future-oriented variant of the spotlight effect. The results of three experiments supported this prediction. Experiment 1 revealed a reduction in egocentric spotlighting when participants imagined an event in the far compared with near future. Experiments 2 and 3 demonstrated reduced spotlighting and feelings of embarrassment when participants viewed an impending event from a third-person (vs. first-person) vantage point. Simple changes in one's visual perspective may be sufficient to diminish the illusion of personal salience.


Assuntos
Atenção , Ego , Imaginação , Autoimagem , Adulto , Feminino , Humanos , Masculino , Percepção Social , Adulto Jovem
5.
Faraday Discuss ; 189: 85-103, 2016 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-27104223

RESUMO

Low cost pollution sensors have been widely publicized, in principle offering increased information on the distribution of air pollution and a democratization of air quality measurements to amateur users. We report a laboratory study of commonly-used electrochemical sensors and quantify a number of cross-interferences with other atmospheric chemicals, some of which become significant at typical suburban air pollution concentrations. We highlight that artefact signals from co-sampled pollutants such as CO2 can be greater than the electrochemical sensor signal generated by the measurand. We subsequently tested in ambient air, over a period of three weeks, twenty identical commercial sensor packages alongside standard measurements and report on the degree of agreement between references and sensors. We then explore potential experimental approaches to improve sensor performance, enhancing outputs from qualitative to quantitative, focusing on low cost VOC photoionization sensors. Careful signal handling, for example, was seen to improve limits of detection by one order of magnitude. The quantity, magnitude and complexity of analytical interferences that must be characterised to convert a signal into a quantitative observation, with known uncertainties, make standard individual parameter regression inappropriate. We show that one potential solution to this problem is the application of supervised machine learning approaches such as boosted regression trees and Gaussian processes emulation.

6.
Environ Sci Technol ; 49(2): 1025-34, 2015 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-25494849

RESUMO

Direct measurements of NOx concentration and flux were made from a tall tower in central London, UK as part of the Clean Air for London (ClearfLo) project. Fast time resolution (10 Hz) NO and NO2 concentrations were measured and combined with fast vertical wind measurements to provide top-down flux estimates using the eddy covariance technique. Measured NOx fluxes were usually positive and ranged from close to zero at night to 2000-8000 ng m(-2) s(-1) during the day. Peak fluxes were usually observed in the morning, coincident with the maximum traffic flow. Measurements of the NOx flux have been scaled and compared to the UK National Atmospheric Emissions Inventory (NAEI) estimate of NOx emission for the measurement footprint. The measurements are on average 80% higher than the NAEI emission inventory for all of London. Observations made in westerly airflow (from parts of London where traffic is a smaller fraction of the NOx source) showed a better agreement on average with the inventory. The observations suggest that the emissions inventory is poorest at estimating NOx when traffic is the dominant source, in this case from an easterly direction from the BT Tower. Agreement between the measurements and the London Atmospheric Emissions Inventory (LAEI) are better, due to the more explicit treatment of traffic flow by this more detailed inventory. The flux observations support previous tailpipe observations of higher NOx emitted from the London vehicle diesel fleet than is represented in the NAEI or predicted for several EURO emission control technologies. Higher-than-anticipated vehicle NOx is likely responsible for the significant discrepancies that exist in London between observed NOx and long-term NOx projections.


Assuntos
Poluentes Atmosféricos/análise , Óxido Nítrico/análise , Dióxido de Nitrogênio/análise , Nitrogênio/análise , Emissões de Veículos/análise , Atmosfera , Monitoramento Ambiental/métodos , Gases , Londres
7.
Gut ; 60(10): 1345-53, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21459928

RESUMO

BACKGROUND AND AIMS: Inappropriate immune responses contribute to the continuous stimulation of the intestinal immune system in chronic inflammatory bowel disease (IBD). Among several pathogenic factors, a numerical deficiency of regulatory T (Treg) cells has been suggested to lead to an insufficient compensation of chronically activated T lymphocytes. This study was conducted to investigate whether increased apoptosis contributes to Treg cell deficiency in IBD and whether successful treatment with antitumour necrosis factor α (TNFα) is achieved by reducing of Treg cell apoptosis. METHODS: Apoptosis of CD4(+)Foxp3(+) Treg cells in tissue sections of patients with active IBD was analysed by immunohistochemistry and TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labelling) staining. Apoptosis of peripheral blood CD4(+)CD25(+)Foxp3(+) Treg cells was investigated by flow cytometry and annexin-V staining. In addition, caspase activity and apoptosis were measured in sera of patients with IBD treated with anti-TNFα by a luminometric caspase enzyme assay. RESULTS: It is demonstrated that patients with active IBD revealed increased apoptosis of local CD4(+)Foxp3(+) Treg cells in the inflamed mucosa compared with non-inflamed control colon tissue. Moreover, in peripheral blood a reduced frequency and increased apoptosis of Treg cells were found and accompanied by elevated caspase activity in the serum. During anti-TNFα treatment, Treg cell apoptosis declined in close correlation with elevated peripheral Treg cell numbers and a decrease of caspase activation and disease activity. CONCLUSIONS: These data suggest that increased apoptosis of Treg cells plays a potentially important role in the pathogenesis of IBD and can be reversed by anti-TNFα treatment. Measurement of Treg cell apoptosis and serum caspase activity might therefore represent promising tools for monitoring disease activity and treatment response in patients with IBD.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Apoptose/imunologia , Doenças Inflamatórias Intestinais/patologia , Linfócitos T Reguladores/patologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto , Idoso , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais/administração & dosagem , Biópsia , Doença Crônica , Colo/imunologia , Colo/patologia , Feminino , Citometria de Fluxo , Seguimentos , Humanos , Íleo/imunologia , Íleo/patologia , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/imunologia , Infliximab , Injeções Intravenosas , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Linfócitos T Reguladores/imunologia , Resultado do Tratamento , Adulto Jovem
8.
Nature ; 453(7199): 1232-5, 2008 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-18580948

RESUMO

Increasing tropospheric ozone levels over the past 150 years have led to a significant climate perturbation; the prediction of future trends in tropospheric ozone will require a full understanding of both its precursor emissions and its destruction processes. A large proportion of tropospheric ozone loss occurs in the tropical marine boundary layer and is thought to be driven primarily by high ozone photolysis rates in the presence of high concentrations of water vapour. A further reduction in the tropospheric ozone burden through bromine and iodine emitted from open-ocean marine sources has been postulated by numerical models, but thus far has not been verified by observations. Here we report eight months of spectroscopic measurements at the Cape Verde Observatory indicative of the ubiquitous daytime presence of bromine monoxide and iodine monoxide in the tropical marine boundary layer. A year-round data set of co-located in situ surface trace gas measurements made in conjunction with low-level aircraft observations shows that the mean daily observed ozone loss is approximately 50 per cent greater than that simulated by a global chemistry model using a classical photochemistry scheme that excludes halogen chemistry. We perform box model calculations that indicate that the observed halogen concentrations induce the extra ozone loss required for the models to match observations. Our results show that halogen chemistry has a significant and extensive influence on photochemical ozone loss in the tropical Atlantic Ocean boundary layer. The omission of halogen sources and their chemistry in atmospheric models may lead to significant errors in calculations of global ozone budgets, tropospheric oxidizing capacity and methane oxidation rates, both historically and in the future.


Assuntos
Atmosfera/química , Halogênios/química , Ozônio/química , Água do Mar/química , Clima Tropical , África Ocidental , Oceano Atlântico , Eucariotos/metabolismo , Geografia , Biologia Marinha , Metano/química , Ozônio/análise , Ozônio/efeitos da radiação , Estações do Ano , Água do Mar/microbiologia , Temperatura
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