307 research outputs found
The effect of progressive muscle relaxation on daily cortisol secretion
Abbreviated progressive muscle relaxation (APMR) is a much used stress-management technique. Its efficacy relevant to placebo control is already established in the literature and the primary aim of the present study was to ascertain whether its proven impact on psychological stress measures is matched by a decrease in prevailing levels of the stress-associated hormone cortisol, using accurate and robust measurement based on multiple sampling of full diurnal cortisol secretion profiles. First-year university students can face significant stress in adjustment to academic demands and immersion in a novel social network and provided a convenient study population. One hundred and one first-year students completed APMR with prevailing stress levels assessed a week before and after intervention. Both cortisol and self-report measures were significantly reduced post-intervention by 8% and 10%, respectively. The efficacy of the intervention was independent of, and not modulated by neuroticism, gender, age and smoking status. We also demonstrated that cortisol reduction was unlikely to have been a consequence of adaptation to any initial cortisol elevation prompted by the challenge of the demanding saliva collection protocol. We conclude that the efficacy of APMR in this population extends to reduction in biologically expressed stress levels as well as levels based solely on self-report
Rapid subduction of organic matter by maldanid polychaetes on the North Carolina slope
In situ tracer experiments conducted on the North Carolina continental slope reveal that tube-building worms (Polychaeta: Maldanidae) can, without ingestion, rapidly subduct freshly deposited, algal carbon (13C-labeled diatoms) and inorganic materials (slope sediment and glass beads) to depths of 10 cm or more in the sediment column. Transport over 1.5 days appears to be nonselective but spatially patchy, creating localized, deep hotspots. As a result of this transport, relatively fresh organic matter becomes available soon after deposition to deep-dwelling microbes and other infauna, and both aerobic and anaerobic processes may be enhanced. Comparison of tracer subduction with estimates from a diffusive mixing model using 234Th-based coefficients, suggests that maldanid subduction activities, within 1.5 d of particle deposition, could account for 25–100% of the mixing below 5 cm that occurs on 100-day time scales. Comparisons of community data from the North Carolina slope for different places and times indicate a correlation between the abundance of deep-dwelling maldanids and the abundance and the dwelling depth in the sediment column of other infauna. Pulsed inputs of organic matter occur frequently in margin environments and maldanid polychaetes are a common component of continental slope macrobenthos. Thus, the activities we observe are likely to be widespread and significant for chemical cycling (natural and anthropogenic materials) on the slope. We propose that species like maldanids, that rapidly redistribute labile organic matter within the seabed, probably function as keystone resource modifiers. They may exert a disproportionately strong influence (relative to their abundance) on the structure of infaunal communities and on the timing, location and nature of organic matter diagenesis and burial in continental margin sediments
Guías para la práctica de la autopsia en casos de muerte súbita cardíaca
A pesar de que la muerte súbita cardíaca es una de las formas más importantes de muerte en los países occidentales, este problema no ha recibido la atención que merece por parte de los patólogos y de los médicos de los sistemas públicos de salud. Se han desarrollado nuevos métodos de prevención de arritmias potencialmente mortales, y el diagnóstico de certeza de las causas de muerte súbita cardíaca es en este momento de particular importancia. Los patólogos son responsables de determinar la causa exacta de la muerte súbita pero existen diferencias considerables en el modo en el que se aborda esta cada vez más compleja tarea. La Asociación Europea de Patología Cardiovascular desarrolló unas guías que representan el estándar mínimo necesario en la práctica habitual de la autopsia para la valoración de la muerte súbita cardíaca, incluyendo no sólo un protocolo para el examen del corazón y el muestreo histopatológico, sino también para la investigación toxicológica y molecular. Nuestras recomendaciones son aplicables a centros médicos universitarios, a hospitales regionales y locales y a todo tipo de Institutos de Medicina Forense. La adopción a lo largo de la Unión Europea de un método uniforme de investigación supondrá la mejora de la práctica habitual, permitirá realizar comparaciones significativas entre distintas comunidades y regiones y, lo que es más importante aún, favorecerá que se monitoricen los patrones de las enfermedades que causan una muerte súbita. Although sudden cardiac death is one of the most important mode of death in Western Countries, pathologists and public health physicians have not given this problem the attention it deserves. New methods of preventing potentially fatal arrhythmias have been developed, and the accurate diagnosis of the causes of sudden cardiac death is now of particular importance. Pathologists are responsible for determining the precise cause of sudden death but there is considerable variation in the way in which they approach this increasingly complex task. The Association for European Cardiovascular Pathology developed guidelines, which represent the minimum standard that is required in the routine autopsy practice for the adequate assessment of sudden cardiac death, including not only a protocol for heart examination and histological sampling, but also for toxicology and molecular investigation. Our recommendations apply to university medical centres, regional and district hospitals and all types of forensic medicine institutes. If a uniform method of investigation is adopted throughout the European Union, this will lead to improvements in standards of practice, allow meaningful comparisons between different communities and regions and, most importantly, permit future trends in the patterns of disease causing sudden death to be monitored
JASPAR 2016: a major expansion and update of the open-access database of transcription factor binding profiles.
JASPAR (http://jaspar.genereg.net) is an open-access database storing curated, non-redundant transcription factor (TF) binding profiles representing transcription factor binding preferences as position frequency matrices for multiple species in six taxonomic groups. For this 2016 release, we expanded the JASPAR CORE collection with 494 new TF binding profiles (315 in vertebrates, 11 in nematodes, 3 in insects, 1 in fungi and 164 in plants) and updated 59 profiles (58 in vertebrates and 1 in fungi). The introduced profiles represent an 83% expansion and 10% update when compared to the previous release. We updated the structural annotation of the TF DNA binding domains (DBDs) following a published hierarchical structural classification. In addition, we introduced 130 transcription factor flexible models trained on ChIP-seq data for vertebrates, which capture dinucleotide dependencies within TF binding sites. This new JASPAR release is accompanied by a new web tool to infer JASPAR TF binding profiles recognized by a given TF protein sequence. Moreover, we provide the users with a Ruby module complementing the JASPAR API to ease programmatic access and use of the JASPAR collection of profiles. Finally, we provide the JASPAR2016 R/Bioconductor data package with the data of this release
BFF: A tool for eliciting tie strength and user communities in social networking services
The final publication is available at Springer via http://dx.doi.org/ 10.1007/s10796-013-9453-6The use of social networking services (SNSs) such as Facebook has explosively grown in the last few years. Users see these SNSs as useful tools to find friends and interact with them. Moreover, SNSs allow their users to share photos, videos, and express their thoughts and feelings. However, users are usually concerned about their privacy when using SNSs. This is because the public image of a subject can be affected by photos or comments posted on a social network. In this way, recent studies demonstrate that users are demanding better mechanisms to protect their privacy. An appropriate approximation to solve this could be a privacy assistant software agent that automatically suggests a privacy policy for any item to be shared on a SNS. The first step for developing such an agent is to be able to elicit meaningful information that can lead to accurate privacy policy predictions. In particular, the information needed is user communities and the strength of users' relationships, which, as suggested by recent empirical evidence, are the most important factors that drive disclosure in SNSs. Given the number of friends that users can have and the number of communities they may be involved on, it is infeasible that users are able to provide this information without the whole eliciting process becoming confusing and time consuming. In this work, we present a tool called Best Friend Forever (BFF) that automatically classifies the friends of a user in communities and assigns a value to the strength of the relationship ties to each one. We also present an experimental evaluation involving 38 subjects that showed that BFF can significantly alleviate the burden of eliciting communities and relationship strength.This work has been partially supported by CONSOLIDER-INGENIO 2010 under grant CSD2007-00022, and TIN 2008-04446 and PROMETEO II/2013/019 projects. This article has been developed as a result of a mobility stay funded by the Erasmus Mundus Programme of the European Comission under the Transatlantic Partnership for Excellence in Engineering - TEE Project.López Fogués, R.; Such Aparicio, JM.; Espinosa Minguet, AR.; García-Fornes, A. (2014). BFF: A tool for eliciting tie strength and user communities in social networking services. Information Systems Frontiers. 16:225-237. https://doi.org/10.1007/s10796-013-9453-6S22523716Blondel, V.D., Guillaume, J.L., Lambiotte, R., Lefebvre, E. (2008). Fast unfolding of communities in large networks. Journal of Statistical Mechanics: Theory and Experiment, 2008(10), P10008.Boyd, D., & Hargittai, E. (2010). Facebook privacy settings: who cares? First Monday, 15(8).Burt, R. (1995). Structural holes: the social structure of competition. Harvard University Pr.Culotta, A., Bekkerman, R., McCallum, A. (2004). 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A genetic approach for long term virtual organization distribution
Electronic versíon of an article published as International Journal on Artificial Intelligent Tools, Volume 20, issue 2, 2011. 10.1142/S0218213011000152. © World Scientific Publishing Company[EN] An agent-based Virtual Organization is a complex entity where dynamic collections of agents agree to share resources in order to accomplish a global goal or offer a complex service. An important problem for the performance of the Virtual Organization is the distribution of the agents across the computational resources. The final distribution should provide a good load balancing for the organization. In this article, a genetic algorithm is applied to calculate a proper distribution across hosts in an agent-based Virtual Organization. Additionally, an abstract multi-agent system architecture which provides infrastructure for Virtual Organization distribution is introduced. The developed genetic solution employs an elitist crossover operator where one of the children inherits the most promising genetic material from the parents with higher probability. In order to validate the genetic proposal, the designed genetic algorithm has been successfully compared to several heuristics in different scenarios. © 2011 World Scientific Publishing Company.This work is supported by TIN2008-04446, TIN2009-13839-C03-01, CSD2007-00022 and FPU grant AP2008-00600 of the Spanish government, and PROMETEO 2008/051 of the Generalitat Valenciana.Sánchez Anguix, V.; Valero Cubas, S.; García Fornes, AM. (2011). A genetic approach for long term virtual organization distribution. International Journal on Artificial Intelligence Tools. 20(2):271-295. https://doi.org/10.1142/S0218213011000152S27129520
INTERTIDAL BIODIVERSITY IN CENTRAL CHILE REVISTA CHILENA DE HISTORIA NATURAL
ABSTRACT Along the coast of central Chile, geographic trends of diversity have been inferred from literature compilations and museum collections based on species range limits for some taxonomic groups. However, spatially-intensive fieldbased assessments of macrobenthic species richness are largely missing. Over the course of a multiyear study (1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005), we characterized latitudinal patterns of rocky intertidal diversity at 18 sites along the coast of central Chile (29-36º S). At each site, the number of sessile and mobile macrobenthic species was quantified in 0.25 m 2 quadrats. Two estimators of local (alpha) diversity were used: observed local species richness, calculated from the asymptote of a species-rarefaction curve, and the Chao2 index, which takes into account the effect of rare species on estimates of local richness. We identified a total of 71 species belonging to 66 genera for a total of 86 taxa. The most diverse groups were herbivorous mollusks (27 taxa) and macroalgae (43 taxa). Diversity showed a complex spatial pattern with areas of high species richness interspersed with areas of low richness. In accordance with previous work, we found no trend in the number of herbivorous mollusks and an inverse and significant latitudinal gradient in the number of algal species. Our results highlight the need for taxonomically diverse assessments of biodiversity of the dominant taxa that conform intertidal communities
Advances in infrastructures and tools for multiagent systems
In the last few years, information system technologies have focused on solving challenges in order to develop distributed applications. Distributed systems can be viewed as collections of service-provider and ser vice-consumer components interlinked by dynamically defined workflows (Luck and McBurney 2008).Alberola Oltra, JM.; Botti Navarro, VJ.; Such Aparicio, JM. (2014). Advances in infrastructures and tools for multiagent systems. Information Systems Frontiers. 16:163-167. doi:10.1007/s10796-014-9493-6S16316716Alberola, J. M., Búrdalo, L., Julián, V., Terrasa, A., & García-Fornes, A. (2014). An adaptive framework for monitoring agent organizations. Information Systems Frontiers, 16(2). doi: 10.1007/s10796-013-9478-x .Alfonso, B., Botti, V., Garrido, A., & Giret, A. (2014). A MAS-based infrastructure for negotiation and its application to a water-right market. 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