Energy efficiency drives the global seasonal distribution of birds.

The uneven distribution of biodiversity on Earth is one of the most general and puzzling patterns in ecology. Many hypotheses have been proposed to explain it, based on evolutionary processes or on constraints related to geography and energy. However, previous studies investigating these hypotheses have been largely descriptive due to the logistical difficulties of conducting controlled experiments on such large geographical scales. Here, we use bird migration-the seasonal redistribution of approximately 15% of bird species across the world-as a natural experiment for testing the species-energy relationship, the hypothesis that animal diversity is driven by energetic constraints. We develop a mechanistic model of bird distributions across the world, and across seasons, based on simple ecological and energetic principles. Using this model, we show that bird species distributions optimize the balance between energy acquisition and energy expenditure while taking into account competition with other species. These findings support, and provide a mechanistic explanation for, the species-energy relationship. The findings also provide a general explanation of migration as a mechanism that allows birds to optimize their energy budget in the face of seasonality and competition. Finally, our mechanistic model provides a tool for predicting how ecosystems will respond to global anthropogenic change

Neural coding tools, based on Information Theory, applied to discrete time series: from electrophysiology to neuroethology

This work is supported by Brazilian agencies Fapesp, CAPES and CNP

Qualidade de vida de pacientes submetidos à cirurgia bariátrica: estudo transversal

Purpose: Analyze factors that influenced the quality of life (QoL) of patients after bariatric surgery. Methods: A cross-sectional study was carried out, involving 307 adult bariatric surgery patients between 2012 and 2014. Data was obtained from the electronic patient records and telephone interviews. To assess the QoL, the World Health Organization Quality of Life-Bref (WHOQOL-bref) was used. A simple linear regression model was constructed, adjusted by sociodemographic variables, with p<0.05. Results: The domains with the worst scores were the physical (mean=58.45; SD±10.42) and environmental (mean=65.19; SD±11.36). The best domains were the social (mean=76.51; SD±15.71) and psychological (mean=68.70; SD±15.71). In the linear regression model, it was observed that time since the surgery was inversely associated with the physical health domain. For each month post-bariatric surgery, the patient’s average score dropped by 2.66 points, adjusted by sex and age. Conclusions: Time since the surgery could be an important determinant of the physical domain score of quality of life. Identifying the quality of life after bariatric surgery and influential factors is fundamental to prepare these patients for the changes deriving from the weight loss.Objetivo: Analizar los factores que influyeron en la calidad de vida (CV) de los pacientes después de la cirugía bariátrica. Métodos: Se llevó a cabo un estudio transversal en el que participaron 307 pacientes adultos con cirugía bariátrica entre 2012 y 2014. Se han obtenido los datos de los registros electrónicos de los pacientes y de sus entrevistas telefónicas. Después se construyó un modelo de regresión lineal simple, ajustado por variables sociodemográficas, con p <0.05. Para evaluar la CV, se utilizó la Calidad de Vida Breve de la Organización Mundial de la Salud (WHOQOL-bref). Resultados: Los dominios con las peores puntuaciones fueron el físico (media = 58,45; SD ± 10,42) y ambiental (media = 65,19; SD ± 11,36). Los mejores dominios fueron el social (media = 76.51; SD ± 15.71) y psicológico (media = 68.70; SD ± 15.71). En el modelo de regresión lineal, se observó que el tiempo desde la cirugía se asoció inversamente con el dominio de la salud física. Por cada mes posterior a la cirugía bariátrica, el puntaje promedio del paciente se redujo en 2.66 puntos, ajustado por sexo y edad. Conclusión: El tiempo transcurrido desde la cirugía puede ser un determinante importante de la puntuación del dominio físico de la calidad de vida. Identificar la calidad de vida después de la cirugía bariátrica y los factores influyentes es fundamental para preparar a estos pacientes para los cambios derivados de la pérdida de peso.Objetivo: Analisar os fatores que influenciaram a qualidade de vida (QV) dos pacientes após a cirurgia bariátrica. Método: Realizado um estudo transversal envolvendo 307 pacientes adultos submetidos à cirurgia bariátrica, no período de 2012 a 2014. Os dados foram obtidos por meio de prontuário eletrônico e entrevistas telefônicas. Para avaliar a QV, foi utilizada a World Health Organization Quality of Life-bref (WHOQOL-bref). Um modelo de regressão linear simples foi construído, ajustado por variáveis sociodemográficas, com p <0,05.Resultados: Os domínios com os piores escores foram físico (média = 58,45; DP ± 10,42) e ambiental (média = 65,19; DP ± 11,36). Os melhores domínios foram o social (média = 76,51; DP ± 15,71) e o psicológico (média = 68,70; DP ± 15,71). No modelo de regressão linear, observou-se que o tempo desde a cirurgia foi inversamente associado ao domínio saúde física. Para cada mês pós-cirurgia bariátrica, a pontuação média do paciente caiu em 2,66 pontos, ajustada por sexo e idade. Conclusão: O tempo desde a cirurgia pode ser um importante determinante do escore do domínio físico de QV. Identificar a QV após a cirurgia bariátrica e fatores que a influenciam é fundamental para preparar esses pacientes para as mudanças decorrentes da perda de peso

The dynamics of apparent horizons in Robinson-Trautman spacetimes

We present an alternative scheme of finding apparent horizons based on spectral methods applied to Robinson-Trautman spacetimes. We have considered distinct initial data such as representing the spheroids of matter and the head-on collision of two non-rotating black holes. The evolution of the apparent horizon is presented. We have obtained in some cases a mass gap between the final Bondi and apparent horizon masses, whose implications were briefly commented in the light of the thermodynamics of black holes.Comment: 9 pages, 7 figure

Estimating the incidence of acute infectious intestinal disease in the community in the UK:A retrospective telephone survey

Objectives: To estimate the burden of intestinal infectious disease (IID) in the UK and determine whether disease burden estimations using a retrospective study design differ from those using a prospective study design. Design/Setting: A retrospective telephone survey undertaken in each of the four countries comprising the United Kingdom. Participants were randomly asked about illness either in the past 7 or 28 days. Participants: 14,813 individuals for all of whom we had a legible recording of their agreement to participate Outcomes: Self-reported IID, defined as loose stools or clinically significant vomiting lasting less than two weeks, in the absence of a known non-infectious cause. Results: The rate of self-reported IID varied substantially depending on whether asked for illness in the previous 7 or 28 days. After standardising for age and sex, and adjusting for the number of interviews completed each month and the relative size of each UK country, the estimated rate of IID in the 7-day recall group was 1,530 cases per 1,000 person-years (95% CI: 1135 – 2113), while in the 28-day recall group it was 533 cases per 1,000 person-years (95% CI: 377 – 778). There was no significant variation in rates between the four countries. Rates in this study were also higher than in a related prospective study undertaken at the same time. Conclusions: The estimated burden of disease from IID varied dramatically depending on study design. Retrospective studies of IID give higher estimates of disease burden than prospective studies. Of retrospective studies longer recall periods give lower estimated rates than studies with short recall periods. Caution needs to be exercised when comparing studies of self-reported IID as small changes in study design or case definition can markedly affect estimated rates

A2 Noradrenergic Lesions Prevent Renal Sympathoinhibition Induced by Hypernatremia in Rats

Renal vasodilation and sympathoinhibition are recognized responses induced by hypernatremia, but the central neural pathways underlying such responses are not yet entirely understood. Several findings suggest that A2 noradrenergic neurons, which are found in the nucleus of the solitary tract (NTS), play a role in the pathways that contribute to body fluid homeostasis and cardiovascular regulation. The purpose of this study was to determine the effects of selective lesions of A2 neurons on the renal vasodilation and sympathoinhibition induced by hypertonic saline (HS) infusion. Male Wistar rats (280–350 g) received an injection into the NTS of anti-dopamine-beta-hydroxylase-saporin (A2 lesion; 6.3 ng in 60 nl; n = 6) or free saporin (sham; 1.3 ng in 60 nl; n = 7). Two weeks later, the rats were anesthetized (urethane 1.2 g⋅kg−1 b.wt., i.v.) and the blood pressure, renal blood flow (RBF), renal vascular conductance (RVC) and renal sympathetic nerve activity (RSNA) were recorded. In sham rats, the HS infusion (3 M NaCl, 1.8 ml⋅kg−1 b.wt., i.v.) induced transient hypertension (peak at 10 min after HS; 9±2.7 mmHg) and increases in the RBF and RVC (141±7.9% and 140±7.9% of baseline at 60 min after HS, respectively). HS infusion also decreased the RSNA (−45±5.0% at 10 min after HS) throughout the experimental period. In the A2-lesioned rats, the HS infusion induced transient hypertension (6±1.4 mmHg at 10 min after HS), as well as increased RBF and RVC (133±5.2% and 134±6.9% of baseline at 60 min after HS, respectively). However, in these rats, the HS failed to reduce the RSNA (115±3.1% at 10 min after HS). The extent of the catecholaminergic lesions was confirmed by immunocytochemistry. These results suggest that A2 noradrenergic neurons are components of the neural pathways regulating the composition of the extracellular fluid compartment and are selectively involved in hypernatremia-induced sympathoinhibition

Author Correction: Simulation-based reconstruction of global bird migration over the past 50,000 years.

An amendment to this paper has been published and can be accessed via a link at the top of the paper

Effectiveness of protected areas in conserving tropical forest birds.

Protected areas (PAs) are the cornerstones of global biodiversity conservation efforts, but to fulfil this role they must be effective at conserving the ecosystems and species that occur within their boundaries. Adequate monitoring datasets that allow comparing biodiversity between protected and unprotected sites are lacking in tropical regions. Here we use the largest citizen science biodiversity dataset - eBird - to quantify the extent to which protected areas in eight tropical forest biodiversity hotspots are effective at retaining bird diversity. We find generally positive effects of protection on the diversity of bird species that are forest-dependent, endemic to the hotspots, or threatened or Near Threatened, but not on overall bird species richness. Furthermore, we show that in most of the hotspots examined this benefit is driven by protected areas preventing both forest loss and degradation. Our results provide evidence that, on average, protected areas contribute measurably to conserving bird species in some of the world's most diverse and threatened terrestrial ecosystems

Effects of whey protein supplement in the elderly submitted to resistance training:systematic review and meta-analysis

Aim: We performed a systematic review to map the evidence and analyze the effect of whey protein supplementation in the elderly submitted to resistance training.  Methods: A comprehensive search on Medline, LILACS, EMBASE, and the Cochrane Library for relevant publications was conducted until August 2015. The terms used in the search were: “Resistance training”; “Whey protein”; “Elderly”.  Results: A total of 632 studies were screened. Five studies were included composing a sample of 391 patients. The supplement whey protein was associated with higher total protein ingestion 9.40 (95% CI: 4.03–14.78), and with an average change in plasma leucine concentration. The supplementation was also associated with increased mixed muscle protein synthesis 1.26 (95% CI: 0.46–2.07) compared to the control group.  Conclusion: We observed an increase in total protein intake, resulting in increased concentration of leucine and mixed muscle protein fractional synthesis rate

Transition of plasmodium sporozoites into liver stage-like forms is regulated by the RNA binding protein pumilio

Many eukaryotic developmental and cell fate decisions that are effected post-transcriptionally involve RNA binding proteins as regulators of translation of key mRNAs. In malaria parasites (Plasmodium spp.), the development of round, non-motile and replicating exo-erythrocytic liver stage forms from slender, motile and cell-cycle arrested sporozoites is believed to depend on environmental changes experienced during the transmission of the parasite from the mosquito vector to the vertebrate host. Here we identify a Plasmodium member of the RNA binding protein family PUF as a key regulator of this transformation. In the absence of Pumilio-2 (Puf2) sporozoites initiate EEF development inside mosquito salivary glands independently of the normal transmission-associated environmental cues. Puf2- sporozoites exhibit genome-wide transcriptional changes that result in loss of gliding motility, cell traversal ability and reduction in infectivity, and, moreover, trigger metamorphosis typical of early Plasmodium intra-hepatic development. These data demonstrate that Puf2 is a key player in regulating sporozoite developmental control, and imply that transformation of salivary gland-resident sporozoites into liver stage-like parasites is regulated by a post-transcriptional mechanism