22 research outputs found

    Sleep characteristics across the lifespan in 1.1 million people from the Netherlands, United Kingdom and United States: a systematic review and meta-analysis

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    How long does the average person sleep? Here, Kocevska et al. conducted a meta-analysis including over 1.1 million people to produce age- and sex-specific population reference charts for sleep duration and efficiency.We aimed to obtain reliable reference charts for sleep duration, estimate the prevalence of sleep complaints across the lifespan and identify risk indicators of poor sleep. Studies were identified through systematic literature search in Embase, Medline and Web of Science (9 August 2019) and through personal contacts. Eligible studies had to be published between 2000 and 2017 with data on sleep assessed with questionnaires including >= 100 participants from the general population. We assembled individual participant data from 200,358 people (aged 1-100 years, 55% female) from 36 studies from the Netherlands, 471,759 people (40-69 years, 55.5% female) from the United Kingdom and 409,617 people (>= 18 years, 55.8% female) from the United States. One in four people slept less than age-specific recommendations, but only 5.8% slept outside of the 'acceptable' sleep duration. Among teenagers, 51.5% reported total sleep times (TST) of less than the recommended 8-10 h and 18% report daytime sleepiness. In adults (>= 18 years), poor sleep quality (13.3%) and insomnia symptoms (9.6-19.4%) were more prevalent than short sleep duration (6.5% with TST = 9 h in bed, whereas poor sleep quality was more frequent in those spending = 41 years) reported sleeping shorter times or slightly less efficiently than men, whereas with actigraphy they were estimated to sleep longer and more efficiently than man. This study provides age- and sex-specific population reference charts for sleep duration and efficiency which can help guide personalized advice on sleep length and preventive practices.Pathophysiology, epidemiology and therapy of agein

    Forest and woodland replacement patterns following drought-related mortality

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    Forest vulnerability to drought is expected to increase under anthropogenic climate change, and drought-induced mortality and community dynamics following drought have major ecological and societal impacts. Here, we show that tree mortality concomitant with drought has led to short-term (mean 5 y, range 1 to 23 y after mortality) vegetation-type conversion in multiple biomes across the world (131 sites). Self-replacement of the dominant tree species was only prevalent in 21% of the examined cases and forests and woodlands shifted to nonwoody vegetation in 10% of them. The ultimate temporal persistence of such changes remains unknown but, given the key role of biological legacies in long-term ecological succession, this emerging picture of postdrought ecological trajectories highlights the potential for major ecosystem reorganization in the coming decades. Community changes were less pronounced under wetter postmortality conditions. Replacement was also influenced by management intensity, and postdrought shrub dominance was higher when pathogens acted as codrivers of tree mortality. Early change in community composition indicates that forests dominated by mesic species generally shifted toward more xeric communities, with replacing tree and shrub species exhibiting drier bioclimatic optima and distribution ranges. However, shifts toward more mesic communities also occurred and multiple pathways of forest replacement were observed for some species. Drought characteristics, species-specific environmental preferences, plant traits, and ecosystem legacies govern postdrought species turnover and subsequent ecological trajectories, with potential far-reaching implications for forest biodiversity and ecosystem services

    Linking dietary energy and skeletal development in the horse Vinculação de energia na dieta e desenvolvimento do esqueleto do cavalo

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    Athletic production is what is sought from the horse. As mammary development is important to the dairy cow, skeletal development is important to horses meeting their production goals. As any integrative physiologist will appreciate, the variables that come together to result in optimal skeletal development are complex. Nutrition is one of these, and it contains two broad variables; the supply of dietary nutrients and energy. This presentation will focus on dietary energy and its links with skeletal development. I propose that it is not simply the amount of dietary energy, but the way and from that that energy is supplied that impacts skeletal development. Through an understanding of how dietary energy impact skeletal development, more precise feeding management strategies can be developed to reduce the risk of skeletal abnormalities and even potentially improve skeletal integrity.<br>Produção atlética é o que se exige do cavalo. Do mesmo modo que o desenvolvimento das glândulas mamárias é importante para vaca leiteira, o desenvolvimento do esqueleto é importante para os cavalos atingirem as metas de produção. Como qualquer fisiologista integrador vai apreciar, as variáveis necessárias para se atingir o desenvolvimento ideal do esqueleto são complexas. A nutrição é uma destas variáveis que contém outras duas mais amplas: fornecimento de nutrientes e energia da dieta. Esta apresentação irá focar na energia da dieta e seus vínculos com o desenvolvimento do esqueleto. Proponho que não é simplesmente a quantidade de energia da dieta, mas a maneira como essa energia será fornecida e quais serão os impactos sobre o desenvolvimento do esqueleto. O entendimento do impacto da energia da dieta sobre o desenvolvimento do esqueleto pode gerar estratégias de gestão de alimentação mais precisas para reduzir o risco de anormalidades esqueléticas e até melhorar potencialmente a integridade do esqueleto
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