Plant litter dynamics in the forest-stream interface: Precipitation is a major control across tropical biomes

Riparian plant litter is a major energy source for forested streams across the world and its decomposition has repercussions on nutrient cycling, food webs and ecosystem functioning. However, we know little about plant litter dynamics in tropical streams, even though the tropics occupy 40% of the Earth's land surface. Here we investigated spatial and temporal (along a year cycle) patterns of litter inputs and storage in multiple streams of three tropical biomes in Brazil (Atlantic forest, Amazon forest and Cerrado savanna), predicting major differences among biomes in relation to temperature and precipitation regimes. Precipitation explained most of litter inputs and storage, which were generally higher in more humid biomes (litterfall: 384, 422 and 308 g m-2 y-1, storage: 55, 113 and 38 g m-2, on average in Atlantic forest, Amazon and Cerrado, respectively). Temporal dynamics varied across biomes in relation to precipitation and temperature, with uniform litter inputs but seasonal storage in Atlantic forest streams, seasonal inputs in Amazon and Cerrado streams, and aseasonal storage in Amazon streams. Our findings suggest that litter dynamics vary greatly within the tropics, but point to the major role of precipitation, which contrasts with the main influence of temperature in temperate areas. © 2017 The Author(s)

Heart rate variability during sleep in children with autism spectrum disorder

PURPOSE: Autonomic dysfunction has been reported in autism spectrum disorder (ASD). Less is known about autonomic function during sleep in ASD. The objective of this study is to provide insight into the autonomic cardiovascular control during different sleep stages in ASD. We hypothesized that patients with ASD have lower vagal and higher sympathetic modulation with elevated heart rate (HR), as compared to typical developing children (TD). METHODS: We studied 21 children with ASD and 23 TD children during overnight polysomnography. Heart rate and spectral parameters were calculated for each vigilance stage during sleep. Data from the first four sleep cycles were used to avoid possible effects of different individual sleep lengths and sleep cycle structures. Linear regression models were applied to study the effects of age and diagnosis (ASD and TD). RESULTS: In both groups, HR decreased during non-REM sleep and increased during REM sleep. However, HR was significantly higher in stages N2, N3 and REM sleep in the ASD group. Children with ASD showed less high frequency (HF) modulation during N3 and REM sleep. LF/HF ratio was higher during REM. Heart rate decreases with age at the same level in ASD and in TD. We found an age effect in LF in REM different in ASD and TD. CONCLUSION: Our findings suggest possible deficits in vagal influence to the heart during sleep, especially during REM sleep. Children with ASD may have higher sympathetic dominance during sleep but rather due to decreased vagal influence

Occupational Burnout Syndrome in the nursing context: an integrative literature review

OBJECTIVE To characterize the scientific production on Burnout Syndrome in the Nursingcontext, systematizing the location where the studies were carried out, the related constructs, the employed methods and their main results. METHOD An integrative review of the literature with a bibliometric approach of articles published in Portuguese, Spanish and English between 2005 and 2016. RESULTS 106 articles wereincluded. Mostinvolvedprevalence, and were descriptive, quantitative studies performed in hospitals.The Southeastern and Southern regions of Brazil had the largest number of publications, and stress was the construct most related to burnout.Most of the studies used the Maslach Burnout Inventory to investigate the presence of the syndrome. CONCLUSION New case-control and cohort studies should be carried out.Qualitative-exploratory studies are necessary to better understand Burnout Syndrome among nursing professionals usingfocus groups or interviews, as well as comparative causal studies, with the purpose of exploring the syndrome’smanifestations.OBJETIVO Caracterizar a produção científica sobre a Síndrome do Esgotamento Profissionalno contexto da enfermagem, sistematizando os locais onde as pesquisas foram realizadas, os construtos relacionados, os métodos empregados e seus principais resultados. MÉTODO Revisão integrativa da literatura, com abordagem bibliométrica, em artigos na língua portuguesa, espanhola e inglesa publicados entre 2005 e 2016. RESULTADOS Foram selecionados 106 artigos.A maioria estudos de prevalência, descritivos, quantitativos e realizados em hospitais. Nas regiões Sudeste e Sul do Brasil encontram-se o maior número de publicações, sendo o estresse o construto mais relacionado com o esgotamento profissional. A maior parte dos estudos utilizou o Maslach Burnout Inventory como meio de averiguação da presença da síndrome. CONCLUSÃO Novos estudos de caso controle e coorte devem ser realizados. Pesquisas de cunho qualitativo-exploratório são necessárias para poder compreender melhor a Síndrome do Esgotamento Profissionalentre os profissionais de enfermagem com grupos focais ou entrevistas, como também pesquisas causais comparativas, com o intuito de explorar as manifestações da síndrome.OBJETIVO Caracterizar la producción científica acerca del Síndrome del Agotamiento Profesionalen el marco de la enfermería, sistematizando los sitios en donde las investigaciones fueron realizadas, los constructos relacionados, los métodos empleados y sus principales resultados. MÉTODO Revisión integrativa de la literatura, con abordaje bibliométrico, en artículos en lengua portuguesa, española e inglesa publicados entre 2005 y 2016. RESULTADOS Fueron seleccionados 106 artículos. La mayoría se compuso de estudios de prevalencia, descriptivos, cuantitativos y realizados en hospitales. En las regiones Sureste y Sur de Brasil se halla el mayor número de publicaciones, siendo el estrés el constructo más relacionado con el agotamiento profesional. La mayor parte de los estudios utilizó el Maslach Burnout Inventorycomo medio de la averiguación de la presencia del síndrome. CONCLUSIÓN Nuevos estudios de caso control y cohorte deben llevarse a cabo. Investigaciones de cuño cualitativo-exploratorio son necesarias para poder comprender mejor el Síndrome del Agotamiento Profesionalentre los profesionales de enfermería con grupos focales o entrevistas, como también investigaciones causales comparativas, a fin de explorar las manifestaciones del síndrome