1,145 research outputs found

    Neural Effects of the Social Environment

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    Epidemiological studies have suggested that the association between city upbringing and minority status with risk for schizophrenia can be explained by social mechanisms. Neuroimaging approaches hold promise for investigating this claim. Recent studies have shown that in healthy individuals, city upbringing and minority status are associated with increased activity in brain circuits involved in emotion regulation during social evaluative processing. These findings support the hypothesis that changes in the ability to regulate social stress contribute to the mechanism of risk. This is in accordance with a body of evidence demonstrating the sensitivity of the human brain to social stress, based on observational studies investigating the neurological sequelae of interpersonal trauma and experimental studies manipulating exposure to interpersonal distress. In this report, we summarize these initial findings, discuss methodological and conceptual challenges of pursuing this line of inquiry in schizophrenia, and suggest an outline for future research

    Circulating insulin-like growth factor I modulates mood and is a biomarker of vulnerability to stress:from mouse to man

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    Individual susceptibility to anxiety disorders after maladaptive responses to stress is not well understood. We now report that while exploring stress responses in mice after traumatic brain injury (TBI), a condition associated to stress susceptibility, we observed that the anxiogenic effects of either TBI or exposure to life-threatening experiences (predator) were blocked when both stressors were combined. Because TBI increases the entrance into the brain of serum insulin-like growth factor I (IGF-I), a known modulator of anxiety with a wide range of concentrations in the human population, we then determined whether circulating IGF-I is related to anxiety measures. In mice, anxiety-like responses to predator were inversely related to circulating IGF-I levels. Other indicators of mood regulation such as sensitivity to dexamethasone suppression and expression levels of blood and brain FK506 binding protein 5 (FKBP5), a co-chaperone of the glucocorticoid receptor that regulates its activity, were also associated to circulating IGF-I. Indeed, brain FKBP5 expression in mice was stimulated by IGF-I. In addition, we observed in a large human cohort (n = 2686) a significant relationship between plasma IGF-I and exposure to recent stressful life events, while FKBP5 expression in blood cells was significantly associated to plasma IGF-I levels. Collectively, these data indicate that circulating IGF-I appears to be involved in mood homeostasis across different species. Furthermore, the data in mice allow us to indicate that IGF-I may be acting at least in part by modulating FKBP5 expression

    Serum insulin-like growth factor I regulates brain amyloid-β levels

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    Context-Aware Semantic Association Ranking

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    Discovering complex and meaningful relationships, which we call Semantic Associations, is an important challenge. Just as ranking of documents is a critical component of today\u27s search engines, ranking of relationships will be essential in tomorrow\u27s semantic search engines that would support discovery and mining of the Semantic Web. Building upon our recent work on specifying types of Semantic Associations in RDF graphs, which are possible to create through semantic metadata extraction and annotation, we discuss a framework where ranking techniques can be used to identify more interesting and more relevant Semantic Associations. Our techniques utilize alternative ways of specifying the context using ontology. This enables capturing users\u27 interests more precisely and better quality results in relevance ranking

    XSHOOTER spectroscopy of the enigmatic planetary nebula Lin49 in the Small Magellanic Cloud

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    We performed a detailed spectroscopic analysis of the fullerene C60-containing planetary nebula (PN) Lin49 in the Small Magellanic Cloud (SMC) using XSHOOTER at the European Southern Observatory Very Large Telescope and the Spitzer/Infrared Spectrograph instruments. We derived nebular abundances for nine elements. We used TLUSTY to derive photospheric parameters for the central star. Lin49 is C-rich and metal-deficient PN (Z ∼ 0.0006). The nebular abundances are in good agreement with asymptotic giant branch nucleosynthesis models for stars with initial mass 1.25 M⊙ and metallicity Z = 0.001. Using the TLUSTY synthetic spectrum of the central star to define the heating and ionizing source, we constructed the photoionization model with CLOUDY that matches the observed spectral energy distribution (SED) and the line fluxes in the UV to far-IR wavelength ranges simultaneously. We could not fit the ∼1–5 μm SED using a model with 0.005–0.1-μm-sized graphite grains and a constant hydrogen density shell owing to the prominent near-IR excess, while at other wavelengths the model fits the observed values reasonably well. We argue that the near-IR excess might indicate either (1) the presence of very small particles in the form of small carbon clusters, small graphite sheets, or fullerene precursors, or (2) the presence of a high-density structure surrounding the central star. We found that SMC C60 PNe show a near-IR excess component to lesser or greater degree. This suggests that these C60 PNe might maintain a structure nearby their central star

    Age estimation by tooth/pulp ratio in canines by peri-apical X-rays: reliability in age determination of Spanish and Italian medieval skeletal remains

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    Estimation of age at death is an unavoidable step in the process of human identification, both in forensic practice and in the anthropological and palaeopathological study of skeletal remains. In several cases, in which medical or demographic records are completely lacking, a reliable estimation of the age at death becomes very important. Skeletal remains from archaeological contexts suffer from several biasing factors such as post-mortem changes, taphonomy and various burial practices depending on age, sex and social status of the deceased persons. Currently, anthropological methods of age determination reveal several possibilities of inaccuracy. Of all the body parts used in age estimation, teeth are the least affected by any taphonomic process. Although there are many dental methods for age at death estimation, some of them are very complex and/or destructive and they are not normally used in anthropology. However, study of the apposition of secondary dentine by examining peri-apical X-rays of canines is beginning to supply very interesting results. The aim of this work was to test Cameriere\u2019s method on a large sample of historical subjects from several cemeteries in Spain and Italy. The Spanish sample belongs to the Medieval cemetery of La Torrecilla (Arenas del Rey, Granada) and is housed in the Laboratory of Anthropology, Faculty of Medicine, University of Granada. The Italian samples come from the Medieval cemeteries of Comacchio (Ferrara) and Castel S. Pietro (Bologna). In order to test the reliability of Cameriere\u2019s method, age estimations of canines were compared with the mean ranges of age of the most commonly applied anthropological methods such as tooth wear changes in the pubic symphysis or the metamorphosis of the auricular surface of the ilium. Tests on these Middle Ages cemeteries produced satisfactory results, indicating that Cameriere\u2019s method is a reliable tool in determining age at death in skeletal remains of archaeological context

    Herschel Planetary Nebula Survey (HerPlaNS) - First Detection of OH+ in Planetary Nebulae

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    We report the first detections of OH+^+ emission in planetary nebulae (PNe). As part of an imaging and spectroscopy survey of 11 PNe in the far-IR using the PACS and SPIRE instruments aboard the Herschel Space Observatory, we performed a line survey in these PNe over the entire spectral range between 51 and 672μ\mum to look for new detections. OH+^+ rotational emission lines at 152.99, 290.20, 308.48, and 329.77μ\mum were detected in the spectra of three planetary nebulae: NGC 6445, NGC 6720, and NGC 6781. Excitation temperatures and column densities derived from these lines are in the range of 27 to 47 K and 2×\times1010^{10} to 4 ×\times1011^{11} cm2^{-2}, respectively. In PNe, the OH+ rotational line emission appears to be produced in the photodissociation region (PDR) in these objects. The emission of OH+ is observed only in PNe with hot central stars (Teff_{eff} > 100000 K), suggesting that high-energy photons may play a role in the OH+ formation and its line excitation in these objects, as it seems to be the case for ultraluminous galaxies.Comment: 9 pages, 7 figures; accepted for publication in A&

    Trait self-reflectiveness relates to time-varying dynamics of resting state functional connectivity and underlying structural connectomes:Role of the default mode network

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    BACKGROUND: Cognitive insight is defined as the ability to reflect upon oneself (i.e. self-reflectiveness), and to not be overly confident of one's own (incorrect) beliefs (i.e. self-certainty). These abilities are impaired in several disorders, while they are essential for the evaluation and regulation of one's behavior. We hypothesized that cognitive insight is a dynamic process, and therefore examined how it relates to temporal dynamics of resting state functional connectivity (FC) and underlying structural network characteristics in 58 healthy individuals. METHODS: Cognitive insight was measured with the Beck Cognitive Insight Scale. FC characteristics were calculated after obtaining four FC states with leading eigenvector dynamics analysis. Gray matter (GM) and DTI connectomes were based on GM similarity and probabilistic tractography. Structural graph characteristics, such as path length, clustering coefficient, and small-world coefficient, were calculated with the Brain Connectivity Toolbox. FC and structural graph characteristics were correlated with cognitive insight. RESULTS: Individuals with lower cognitive insight switched more and spent less time in a globally synchronized state. Additionally, individuals with lower self-reflectiveness spent more time in, had a higher probability of, and had a higher chance of switching to a state entailing default mode network (DMN) areas. With lower self-reflectiveness, DTI-connectomes were segregated less (i.e. lower global clustering coefficient) with lower embeddedness of the left angular gyrus specifically (i.e. lower local clustering coefficient). CONCLUSIONS: Our results suggest less stable functional and structural networks in individuals with poorer cognitive insight, specifically self-reflectiveness. An overly present DMN appears to play a key role in poorer self-reflectiveness

    Incidencia de las nuevas tecnologías en el valor percibido de los servicios en el sector de la comunicación en Aragón

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    El sector de las empresas de comunicación, considerando como tales tanto medios como agencias de publicidad, ha cambiado enormemente sus prácticas profesionales durante la última década y el valor de los servicios que ofrecen a los anunciantes y a usuarios está en entredicho. Esta investigación estudia la incidencia de la tecnología en los cambios producidos en la estructura competitiva del sector, utilizando como estudio de caso Aragón (España). Mediante la triangulación metodológica, analizamos datos de los principales informes nacionales e internacionales, las percepciones de los profesionales, anunciantes y usuarios. En el presente estudio, proponemos un marco contextual a los decisores estratégicos, que no solo describe la situación actual, sino que permite vislumbrar tendencias. Funciones que tradicionalmente eran asumidas por las agencias de publicidad se han internalizado, tanto en las empresas anunciantes como en los medios de comunicación, ante la facilidad de implementación que ofrecen los nuevos canales de comunicación. Tanto los medios convencionales como los nuevos soportes publicitarios digitales llegan ahora de forma directa a las empresas anunciantes, eliminando de esta forma todo lo que es percibido como intermediación sin valor añadido. En un contexto tecnológico en el que se han reducido enormemente los costes de información y de transacción, es hora de que cada agente económico reflexione sobre su aportación real en la cadena de valor. Mediante esta investigación, hemos aportado algunas claves que pueden ayudar a quienes deban tomar este tipo de decisiones, sean medios o agencias, a comprender los procesos de decisión de sus clientes. During the last decade, the communication companies sector, considering as such both media and advertising agencies, has greatly changed professional practices. The value of the services offered to advertisers and users is being compromised. This research studies the incidence of technology in the changes in the sector's competitive structure, using Aragon (Spain) as a case study. Through methodological triangulation, we analyze data from the main national and international reports, the impressions of professionals, advertisers and users. In the present study, we propose a contextual framework for strategic decision-makers. It not only describes the current situation, but also allows for a glimpse at trends. Functions that, traditionally, were taken on board by publicity agencies have been internalized, both in the advertising companies and in the media, given the ease of implementation offered by the new communication channels. Now, both conventional media and new digital advertising media reach advertisers directly, eliminating what is perceived as intermediation without added value. In a technological context in which the costs of information and transactions have been greatly reduced, it is time for each economic agent to reflect on his real contribution in the value chain. With our research, we have put forward some key factors that allow assistance for those who should take that kind of decisions, whether media or agencies, in order to understand their customers' decision-making processes
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