753 research outputs found

    Developmental conditions modulate DnA methylation at the glucocorticoid receptor gene with cascading effects on expression and corticosterone levels in zebra finches

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    Developmental conditions can impact the adult phenotype via epigenetic changes that modulate gene expression. In mammals, methylation of the glucocorticoid receptor gene Nr3c1 has been implicated as mediator of long-term effects of developmental conditions, but this evidence is limited to humans and rodents, and few studies have simultaneously tested for associations between DNA methylation, gene expression and phenotype. Adverse environmental conditions during early life (large natal brood size) or adulthood (high foraging costs) exert multiple long-term phenotypic effects in zebra finches, and we here test for effects of these manipulations on DNA methylation and expression of the Nr3c1 gene in blood. Having been reared in a large brood induced higher DNA methylation of the Nr3c1 regulatory region in adulthood, and this effect persisted over years. Nr3c1 expression was negatively correlated with methylation at 2 out of 8 CpG sites, and was lower in hard foraging conditions, despite foraging conditions having no effect on Nr3c1 methylation at our target region. Nr3c1 expression also correlated with glucocorticoid traits: higher expression level was associated with lower plasma baseline corticosterone concentrations and enhanced corticosterone reactivity. Our results suggest that methylation of the Nr3c1 regulatory region can contribute to the mechanisms underlying the emergence of long-term effects of developmental conditions in birds, but in our system current adversity dominated over early life experiences with respect to receptor expression.We thank A. Hidalgo, F.M. Miranda and E. Mulder for their assistance and training in the lab; S. Jörg for expertly running the hormone assays; M. Briga for training and assistance with the long-term experiment, and M. Driessen for assistance with sampling. We also thank M. JordĂ  for assistance with the interpretation of methylation data analysis, and the laboratory of ecophysiology and molecular ecology of the EstaciĂłn BiolĂłgica de Doñana for technical support. This project was funded by an EMBO short-term fellowship grant (nÂș7178) and a Dr. J. L. Dobberke Foundation grant (n°0205510782), both awarded to B.J., who was further supported by the University of Groningen and the Max Planck Institute for Ornithology. E.G-D was funded by a Spanish Ministry of Economy and Competitiveness Ramon y Cajal fellowship and by Plan Nacional Grant BFU2015-65000-R.Peer reviewe

    Setting targets leads to greater long-term weight losses and ‘unrealistic’ targets increase the effect in a large community-based commercial weight management group

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    Background. Setting personal targets is an important behavioural component in weight management programmes. Normal practice is to encourage ‘realistic’ weight loss but the under-pinning evidence base for this is limited and controversial. This study investigates the effect of number and size of weight loss targets on long-term weight loss in a large community sample of adults. Methods. Weight change, attendance and target weight data for all new UK members, joining January to March 2012 was extracted from a commercial slimming organisation’s electronic database. Results. Of the 35 380 members who had weight data available at 12 months after joining, 69.1% (n=24 447)had a starting BMI≄30kg/m2. Their mean weight loss was 12.9±7.8% and for both sexes, weight loss at 12 months was greater for those who set targets (p25% was 7.6±4.0 kg/m2. A higher percentage of obese members did not set targets (p<0.001) compared to those with a BMI below 30kg/m2. Conclusions. Much of the variance in achieved weight loss in this population was explained by the number of targets set and the size of the first target. Whilst obese people were less likely to set targets, doing so increased the likelihood of achieving clinically significant weight loss and for some ‘unrealistic’ targets improved results

    Towards the Legal Recognition and Governance of Forest Ecosystem Services in Mozambique

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    Within the context of Mozambique, this paper examines the state of forest ecosystem services, the dependency of the population on these systems for their well-being, if an adaptive governance regime is being created which will ensure the resilience of the forest ecosystem services including the legal framework, the institutions operating within this framework, the tools available and their functioning, and how cooperative governance is operating.  

    Phrases in literary contexts: patterns and distributions of suspensions in Dickens’s novels

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    This paper addresses relations between lexico-grammatical patterns and texts. Our focus is on a specific linguistic unit, the ‘suspended quotation’ (or ‘suspension’), which has received particular attention in Dickens studies. The suspended quotation refers to an interruption of a fictional character’s speech by the narrator with a sequence of at least five words. We show how corpus linguistic methods can help to systematically study suspensions in a corpus of Dickens’s novels: we investigate relationships between patterns of body language presentation and suspensions; we consider the distribution of suspensions across novels; and we illustrate how patterns in suspensions relate to meanings of reporting verbs. Overall, we argue that suspensions are discernible units that contribute to meaningful patterns in narrative prose

    Testing microtubular SOFCs in unmanned air vehicles (UAVs)

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    Unmanned Air Vehicles (UAVs) powered by microtubular SOFCs (mSOFCs) are described for comparison with polymer fuel cells (PEFCs). Using propane as fuel, 7mm diameter mSOFCs have been tested in a 2m wingspan aircraft with a total weight of 6kg. The start-up time was 12 minutes to deliver 250W in a fuel cell/battery hybrid drive system. Tubes were YSZ cermet anode supported, with 10 ”m YSZ electrolyte, 6”m SDC interlayer coated with 50”m LSCF cathode. Silver wires were used as interconnects. Pure propane fuel gas was mixed with air in a CPOX reactor using catalytic fuel processing mesh. A polymeric fuel inlet manifold gave cold sealing at the tube inlet ends which projected out of the hot box. Cathode air was provided in counterflow, preheated over an anode off-gas catalyst. The fuel utilization was 55%, output power of 250W. The fuel cell was incorporated in a hybrid electrical system with lithium polymer battery and inserted in a Skywalker X8 UAV with 500g of propane in an aluminum tank

    Gewerkschaften im deutschen Einheitsprozess

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    The role of the unions in the process of German unity has so far received little attention. From the beginning, they were among the forces that helped shape the social and economic transformation of East Germany. In the volume's volume, scientists and formerly active people from East and West - starting from their respective different perspectives - consider the possibilities, successes and limits of trade union politics and trade union action. The focus is on trade union contacts before 1989, the phases of upheaval and unification, the work of the Treuhandanstalt and tariff policy. The effects of the transformation process are also elaborated

    Population heterogeneity and dynamics in starter culture and lag phase adaptation of the spoilage yeast Zygosaccharomyces bailii to weak acid preservatives

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    The food spoilage yeast Zygosaccharomyces bailii shows great resistance to weak-acid preservatives, including sorbic acid (2, 4-hexadienoic acid). That extreme resistance was shown to be due to population heterogeneity, with a small sub-population of cells resistant to a variety of weak acids, probably caused by a lower internal pH reducing the uptake of all weak acids. In the present paper, it was found that resistant cells were extremely rare in exponential cultures, but increased by up to 8000-fold in stationary phase. Inoculation of media containing sorbic acid with a population of Z. bailii cells gave rise to what appeared to be a prolonged lag phase, suggesting adaptation to the conditions before the cells entered the period of exponential growth. However, the apparent lag phase caused by sorbic acid was largely due to the time required for the resistant sub-population to grow to detectable levels. The slow growth rate of the sub-population was identical to that of the final total population. The non-resistant bulk population remained viable for 3. days but had lost viability by 6. days and, during that time, there was no indication of any development of resistance in the bulk population. The sub-population growing in sorbic acid showed very high population diversity in colony size and internal pH. After removal of sorbic acid, the population rapidly reverted back to the normal, largely non-resistant, population distribution. The data presented suggest that a reevaluation of the lag phase in microbial batch culture is required, at least for the resistance of Z. bailii to sorbic acid. Furthermore, the significance of phenotypic diversity and heterogeneity in microbial populations is discussed more broadly with potential relevance to bacterial "persisters", natural selection and evolution. © 2014
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