601 research outputs found

    Towards self-organized service-oriented multi-agent systems

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    The demand for large-scale systems running in complex and even chaotic environments requires the consideration of new paradigms and technologies that provide flexibility, robustness, agility and responsiveness. Multiagents systems is pointed out as a suitable approach to address this challenge by offering an alternative way to design control systems, based on the decentralization of control functions over distributed autonomous and cooperative entities. However, in spite of their enormous potential, they usually lack some aspects related to interoperability, optimization in decentralized structures and truly self-adaptation. This paper discusses a new perspective to engineer adaptive complex systems considering a 3-layer framework integrating several complementary paradigms and technologies. In a first step, it suggests the integration of multi-agent systems with service-oriented architectures to overcome the limitations of interoperability and smooth migration, followed by the use of technology enablers, such as cloud computing and wireless sensor networks, to provide a ubiquitous and reconfigurable environment. Finally, the resulted service-oriented multi-agent system should be enhanced with biologically inspired techniques, namely self-organization, to reach a truly robust, agile and adaptive system

    In Utero Exposures, Infant Growth, and DNA Methylation of Repetitive Elements and Developmentally Related Genes in Human Placenta

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    BACKGROUND: Fetal programming describes the theory linking environmental conditions during embryonic and fetal development with risk of diseases later in life. Environmental insults in utero may lead to changes in epigenetic mechanisms potentially affecting fetal development. OBJECTIVES: We examined associations between in utero exposures, infant growth, and methylation of repetitive elements and gene-associated DNA in human term placenta tissue samples. METHODS: Placental tissues and associated demographic and clinical data were obtained from subjects delivering at Women and Infants Hospital in Providence, Rhode Island (USA). Methylation levels of long interspersed nuclear element-1 (LINE-1) and the Alu element AluYb8 were determined in 380 placental samples from term deliveries using bisulfite pyrosequencing. Genomewide DNA methylation profiles were obtained in a subset of 184 samples using the Illumina Infinium HumanMethylation27 BeadArray. Multiple linear regression, model-based clustering methods, and gene set enrichment analysis examined the association between birth weight percentile, demographic variables, and repetitive element methylation and gene-associated CpG locus methylation. RESULTS: LINE-1 and AluYb8 methylation levels were found to be significantly positively associated with birth weight percentile (p = 0.01 and p \u3c 0.0001, respectively) and were found to differ significantly among infants exposed to tobacco smoke and alcohol. Increased placental AluYb8 methylation was positively associated with average methylation among CpG loci found in polycomb group target genes; developmentally related transcription factor binding sites were overrepresented for differentially methylated loci associated with both elements. CONCLUSIONS: Our results suggest that repetitive element methylation markers, most notably AluYb8 methylation, may be susceptible to epigenetic alterations resulting from the intrauterine environment and play a critical role in mediating placenta function, and may ultimately inform on the developmental basis of health and disease

    The pursuit of happiness: the social and scientific origins of Hans Selye’s natural philosophy of life

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    © The Author(s) 2012. Open access article.In 1956, Hans Selye tentatively suggested that the scientific study of stress could ‘help us to formulate a precise program of conduct’ and ‘teach us the wisdom to live a rich and meaningful life’. Nearly two decades later, Selye expanded this limited vision of social order into a full-blown philosophy of life. In Stress without Distress, first published in 1974, he proposed an ethical code of conduct designed to mitigate personal and social problems. Basing his arguments on contemporary understandings of the biological processes involved in stress reactions, Selye referred to this code as ‘altruistic egotism’. This article explores the origins and evolution of Selye’s ‘natural philosophy of life’, analysing the links between his theories and adjacent intellectual developments in biology, psychosomatic and psychosocial medicine, cybernetics and socio-biology, and situating his work in the broader cultural framework of modern western societies.Wellcome Trus

    Serial Analysis of the Gut and Respiratory Microbiome in Cystic Fibrosis in Infancy: Interaction between Intestinal and Respiratory Tracts and Impact of Nutritional Exposures

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    Pulmonary damage caused by chronic colonization of the cystic fibrosis (CF) lung by microbial communities is the proximal cause of respiratory failure. While there has been an effort to document the microbiome of the CF lung in pediatric and adult patients, little is known regarding the developing microflora in infants. We examined the respiratory and intestinal microbiota development in infants with CF from birth to 21 months. Distinct genera dominated in the gut compared to those in the respiratory tract, yet some bacteria overlapped, demonstrating a core microbiota dominated by Veillonella and Streptococcus. Bacterial diversity increased significantly over time, with evidence of more rapidly acquired diversity in the respiratory tract. There was a high degree of concordance between the bacteria that were increasing or decreasing over time in both compartments; in particular, a significant proportion (14/16 genera) increasing in the gut were also increasing in the respiratory tract. For 7 genera, gut colonization presages their appearance in the respiratory tract. Clustering analysis of respiratory samples indicated profiles of bacteria associated with breast-feeding, and for gut samples, introduction of solid foods even after adjustment for the time at which the sample was collected. Furthermore, changes in diet also result in altered respiratory microflora, suggesting a link between nutrition and development of microbial communities in the respiratory tract. Our findings suggest that nutritional factors and gut colonization patterns are determinants of the microbial development of respiratory tract microbiota in infants with CF and present opportunities for early intervention in CF with altered dietary or probiotic strategies

    Towards Harmonisation in Landscape Unit Delineation: An Analysis of Spanish Case Studies

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    [EN] The European Landscape Convention has encouraged member states to develop tools for landscape planning and management. Landscape character assessment is the most widespread approach. The aim of this paper is to identify the main trends in landscape unit delineation in Spain. For this purpose, 29 works are analysed by the Multiple Correspondence technique (MCA). Each work is characterised by a category of the variables: scale, type of extent, geomorphology, land matrix and visual boundaries. Results show that there is an implicit hierarchy in the way Spanish professionals are mapping landscape units. It is more apparent in variables related to geomorphology and less evident in variables related to land matrix. Regarding visual boundaries, they are not usually used at small scales and are more frequent at intermediate and large scales. The definition of clear criteria that allow comparable classifications and the increased consideration of cultural and perceptual factors is encouraged for future landscape character classifications.This work was supported by DGI and FEDER grant n8 AGL–2004-03263/AGR. We would like to thank Paz Aramburu, Rafael Escribano, Jordi Puig, the enterprise P&G and Florencio Zoido and Valencia Regional Department of Environment for the data provided for this research and also the R&D&I Linguistic Assistance Office at the Universidad Polite´cnica de Valencia for their help in revising and correcting this paper.Vallés-Planells, M.; Galiana, F.; Bru García, R. (2012). Towards Harmonisation in Landscape Unit Delineation: An Analysis of Spanish Case Studies. Landscape Research. 38(3):329-346. https://doi.org/10.1080/01426397.2011.647896S32934638
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