3,339 research outputs found
Analytical investigation of the atmospheric radiation limits in semigray atmospheres in radiative equilibrium
We model the wavelength-dependent absorption of atmospheric gases by assuming constant mass absorption coefficients in finite-width spectral bands. Such a semigray atmosphere is analytically solved by a discrete ordinate method. The general solution is analyzed for a water vapor saturated atmosphere that also contains a carbon dioxide-like absorbing gas in the infrared. A multiple stable equilibrium with a relative upper limit in the outgoing long-wave radiation is found. Differing from previous radiative–convective models, we find that the amount of carbon dioxide strongly modifies the value of this relative upper limit. This result is also obtained in a gray (i.e., equal absorption of radiation at all infrared wavelengths) water vapor saturated atmosphere. The destabilizing effect of carbon dioxide implies that massive carbon dioxide atmospheres are more likely to reach a runaway greenhouse state than thin carbon dioxide one
A multivariate regional test for detection of trends in extreme rainfall: the case of extreme daily rainfall in the French Mediterranean area
In this paper we present a multivariate regional test we developed for the
detection of trends in extreme rainfall, which takes into account the
spatial dependence between rainfall measurements with copula functions. The
test is based on four steps. It was applied to a set of 92 series of Annual
Daily Maxima (ADM) rainfall in the French Mediterranean area, sampled during
the 1949–2004 observation period. The results show a low significant trend,
concerning mainly the mountains area in the west part of the French
Mediterranean region. The position's parameters of the ADM rainfall
probability distribution functions present a low but significant increasing
trend of about 5% to 10%, the same increase as that observed in ADM
rainfall quantiles in the last 56 years. Further work is needed
to understand if this significative trend is related to the global climate
change or to the natural variability of Mediterranean climate
Trends in survival of older care home residents in England: A 10-year multi-cohort study
Increases in longevity combined with a policy emphasis on caring for older people in their own homes could have widened or narrowed the survival gap between care home and community-dwelling resident older people. Knowledge of pre-COVID-19 trends in this gap is needed to assess the longer-term impacts of the pandemic. We provide evidence for England on recent trends in 1, 2 and 3-year mortality amongst care home residents aged 65+ compared with similar community-dwelling residents. We use the Clinical Practice Research Datalink, a nationally representative primary care database. For each of the ten years from 2006 to 2015, care home and community-dwelling residents aged 65+ were identified and matched in the ratio 1:3, according to age, gender, area deprivation and region. Cox survival analyses were used to estimate mortality risks for care home residents in comparison with similar community-dwelling people, adjusting for age, gender, area deprivation and region. The study sample consisted of ten overlapping cohorts averaging 5495 care home residents per cohort. Adjusted mortality risks increased over the study period for care home residents while decreasing slightly for matched community-dwelling residents. The relative risks (RRs) of mortality associated with care home residence were higher for younger ages and shorter follow-up periods, in all years. Over the decade, the RRs increased, most at younger ages and for shorter follow-up periods (e.g. for the age group 65-74 years, 1-year average RR increased by 61% from 5.4 to 8.8, while for those aged 85-94 years and over, 3-year RR increased by 22% from 1.3 to 1.6). Thus the survival gap between older care home and community-dwelling residents has been widening, especially at younger ages. In due course, it will be possible to establish to what extent the COVID-19 pandemic has resulted in further growth in this gap
Trends in survival of older care home residents in England: A 10-year multi-cohort study
Increases in longevity combined with a policy emphasis on caring for older people in their own homes could have widened or narrowed the survival gap between care home and community-dwelling resident older people. Knowledge of pre-COVID-19 trends in this gap is needed to assess the longer-term impacts of the pandemic. We provide evidence for England on recent trends in 1, 2 and 3-year mortality amongst care home residents aged 65+ compared with similar community-dwelling residents. We use the Clinical Practice Research Datalink, a nationally representative primary care database. For each of the ten years from 2006 to 2015, care home and community-dwelling residents aged 65+ were identified and matched in the ratio 1:3, according to age, gender, area deprivation and region. Cox survival analyses were used to estimate mortality risks for care home residents in comparison with similar community-dwelling people, adjusting for age, gender, area deprivation and region. The study sample consisted of ten overlapping cohorts averaging 5495 care home residents per cohort. Adjusted mortality risks increased over the study period for care home residents while decreasing slightly for matched community-dwelling residents. The relative risks (RRs) of mortality associated with care home residence were higher for younger ages and shorter follow-up periods, in all years. Over the decade, the RRs increased, most at younger ages and for shorter follow-up periods (e.g. for the age group 65–74 years, 1-year average RR increased by 61% from 5.4 to 8.8, while for those aged 85–94 years and over, 3-year RR increased by 22% from 1.3 to 1.6). Thus the survival gap between older care home and community-dwelling residents has been widening, especially at younger ages. In due course, it will be possible to establish to what extent the COVID-19 pandemic has resulted in further growth in this gap
Validacion de una prueba para evaluar memoria de trabajo fonologica y visuoespacial, en ninos de 4 anos a 5 años 11 meses, con desarrollo tipico, de la ciudad de Talca.
92 p.La memoria de trabajo presenta una relación directa con la adquisición del desarrollo de habilidades de procesamiento lingüÃstico, adquisición de la lectura y comprensión de lectura, asà como también en la adquisición de nuevas palabras.
Por esto se hace necesario la validación de una prueba que evalúe especÃficamente la memoria de trabajo fonológica y visuoespacial en niños de 4 años a 5 años 11, para asà detectar de manera temprana alguna dificultad en la adquisición de nuevas habilidades como las ya descrita.
En el presente estudio se validaron los estÃmulos que buscaban medir especÃficamente la memoria de trabajo, dejando fuera de este trabajo aquellos estÃmulos que no cumplÃan su objetivo de medir memoria de trabajo. Asà la prueba, si bien presenta pocos estÃmulos, éstos evalúan especÃficamente la memoria de trabajo tanto fonológica como visuoespacial
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