13,454 research outputs found

    Probing BH mass and accretion through X-ray variability in the CDFS

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    Recent work on nearby AGNs has shown that X-ray variability is correlated with the mass and accretion rate onto the central SMBH. Here we present the application of the variability-luminosity relation to high redshift AGNs in the CDFS, making use of XMM-Newton observations. We use Monte Carlo simulations in order to properly account for bias and uncertainties introduced by the sparse sampling and the very low statistics. Our preliminary results indicate that BH masses span over the range from 10^5 to 10^9 solar mass while accretion rates range from 10^-3 up to values greater than 1, in unit of Eddington accretion rate.Comment: 2 pages, 2 figures,in press in the X-ray 2009 Conference Proceedings (Bologna, 7-11 September 2009

    Attachment, Physiological and Familial Vulnerability in Childhood Obesity: an Interactive Multisystem Approach

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    The aims of the present study were to test the association between insecure attachment and basal cortisol and catecholamines levels in a sample of obese children. The role of familial vulnerability and gender was also investigated. Methods: Cortisol and catecholamines levels of 8- to 13-year olds obese children were measured. Self-report questionnaires were used to assess attachment pattern and current anxiety and depression, and parent-report questionnaires were used to assess attachment, current anxiety and depression and familial vulnerability. Linear regression analyses were performed for individuals that scored low versus high on parental internalizing problems, and for boys and girls, separately. Results: In the group with high parental internalizing problems, insecure attachment was significantly associated with reduced basal levels of cortisol, in boys (p=0.007, b= -0.861, R2= 73.0%). In the group with low parental internalizing problems, the association between insecure attachment and cortisol was not significant in either boys or girls, and it was negative in boys (p=0.075, b= -0.606, R2= 36.7%) and positive in girls (p=0.677, b= 0.176, R2= 3.1%) . Conclusions: Apparently, physiological risk factors for psicopathology in obesity are more evident in individuals with a high familial vulnerability. In addition, patterns of physiological risk for psicopathology in obesity are different in boys and girls. Therefore, it is important to take into account familial vulnerability and gender when investigating physiological risk factors for psycopathology in obesity. Insecure attachment in childhood may be a risk factor for obesity. Interventions to increase children's attachment security should examine the effects on children's weight

    Pre-harvest rindstain of ‘Encore’ mandarin: initial histological signs of epicarp disturbance and extent of the disorder

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    Pre-harvest rindstain in ‘Encore’ mandarin starts by the injury of a few epidermal cells. The connection between the damaged epidermis and the collapsed layers of ïŹ‚avedo, extending in parallel with rind surface was only visible on cross-sections containing the narrow zone of injured epidermal cells. The individual cell alteration including loss of membrane integrity and the accumulation of large amounts of osmiophilic materials in the cytoplasm are the result of a degrading process. Minute disruptions in the cuticle may provide shelters for resting forms of amoeboid or plasmodial-like organisms living on the rind. Our results suggest that these organisms could be involved in the disorder expression.FCT—Fundação para a CiĂȘncia e Tecnologi

    Finite size analysis of a two-dimensional Ising model within a nonextensive approach

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    In this work we present a thorough analysis of the phase transitions that occur in a ferromagnetic 2D Ising model, with only nearest-neighbors interactions, in the framework of the Tsallis nonextensive statistics. We performed Monte Carlo simulations on square lattices with linear sizes L ranging from 32 up to 512. The statistical weight of the Metropolis algorithm was changed according to the nonextensive statistics. Discontinuities in the m(T) curve are observed for q≀0.5q\leq 0.5. However, we have verified only one peak on the energy histograms at the critical temperatures, indicating the occurrence of continuous phase transitions. For the 0.5<q≀1.00.5<q\leq 1.0 regime, we have found continuous phase transitions between the ordered and the disordered phases, and determined the critical exponents via finite-size scaling. We verified that the critical exponents α\alpha , ÎČ\beta and Îł\gamma depend on the entropic index qq in the range 0.5<q≀1.00.5<q\leq 1.0 in the form α(q)=(10q2−33q+23)/20\alpha (q)=(10 q^{2}-33 q+23)/20, ÎČ(q)=(2q−1)/8\beta (q)=(2 q-1)/8 and Îł(q)=(q2−q+7)/4\gamma (q)=(q^{2}-q+7)/4. On the other hand, the critical exponent Îœ\nu does not depend on qq. This suggests a violation of the scaling relations 2ÎČ+Îł=dÎœ2 \beta +\gamma =d \nu and α+2ÎČ+Îł=2\alpha +2 \beta +\gamma =2 and a nonuniversality of the critical exponents along the ferro-paramagnetic frontier.Comment: accepted for publication in Phys. Rev.

    New Insights about Pulmonary Epithelioid Hemangioendothelioma: Review of the Literature and Two Case Reports

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    Pulmonary epithelioid hemangioendothelioma (PEH) is a rare neoplasm of vascular origin. There are three different major imaging patterns identified in thoracic manifestation of epithelioid hemangioendothelioma: (1) multiple pulmonary nodules; (2) multiple pulmonary reticulonodular opacities; and (3) diffuse infiltrative pleural thickening. Radiographically, presence of bilateral multiple nodules is the most common pattern of presentation. The diagnosis is made on the basis of histopathological findings and confirmed by positive immunohistochemistry staining. Although the prognostic factors for PEH have not yet been well established, a better prognosis is usually associated with the multinodular pattern. We report two different imagological presentations of this rare disease, based on two institutional experiences, along with a review of the relevant literature.info:eu-repo/semantics/publishedVersio

    Schwinger's Method for the Massive Casimir Effect

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    We apply to the massive scalar field a method recently proposed by Schwinger to calculate the Casimir effect. The method is applied with two different regularization schemes: the Schwinger original one by means of Poisson formula and another one by means of analytical continuation.Comment: plain TeX, 6 pages, DFTUZ-93-2

    Determination of phytoextraction potential of plant speciesfor toxic elements in soils of abandoned sulphide-mining areas

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    This study has determined contamination levels in soils and plants from the Sa˜o Domingos mining area, Portugal, by k0-INAA. Total concentrations of As, Sb, Cr, Hg, Cu, Zn and Fe in soils were very high, exceeding the maximum limits in Portuguese legislation. Concentrations of toxic elements like As, Sb and Zn were highest in roots of Erica andevalensis, Juncus acutus, Agrostis castellana and Nicotiana glauca. Additionally, As, Br, Cr, Fe, Sb and Zn in all organs of most plants were above toxicity levels. Those species that accumulated relatively high concentrations of toxic elements in roots (and tops) may be cultivated for phytostabilisation of similar areas

    A new method for the solution of the Schrodinger equation

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    We present a new method for the solution of the Schrodinger equation applicable to problems of non-perturbative nature. The method works by identifying three different scales in the problem, which then are treated independently: An asymptotic scale, which depends uniquely on the form of the potential at large distances; an intermediate scale, still characterized by an exponential decay of the wave function and, finally, a short distance scale, in which the wave function is sizable. The key feature of our method is the introduction of an arbitrary parameter in the last two scales, which is then used to optimize a perturbative expansion in a suitable parameter. We apply the method to the quantum anharmonic oscillator and find excellent results.Comment: 4 pages, 4 figures, RevTex

    Antenatal paternal adjustment and paternal attitudes after infertility treatment

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    STUDY QUESTION: Do mode of conception [ART versus Natural (NC)] and depression have an interactive effect on antenatal paternal adjustment and paternal attitudes? SUMMARY ANSWER: Depression increased the negative effect of ART on antenatal paternal adjustment and paternal attitudes, specifically on antenatal marital relationship satisfaction. WHAT IS KNOWN ALREADY: Research on antenatal paternal adjustment and paternal attitudes after ART is scarce and has produced inconsistent results. STUDY DESIGN, SIZE, DURATION: This cross-sectional study assessed 197 primiparous men (71 ART and 126 NC) during their partner’s second trimester of gestation. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were derived from three larger longitudinal studies recruited at public Health Services in Northern Portugal. All men, for who this was their first child and had filled in a socio-demographic questionnaire, measures of depression and anxiety, and antenatal paternal adjustment and paternal attitudes were selected. MAIN RESULTS AND THE ROLE OF CHANCE: An interaction effect of mode of conception and depression was found on antenatal paternal adjustment and paternal attitudes. ART men showing high depressive symptomatology had lower antenatal marital relationship satisfaction than ART men showing low depressive symptomatology and NC men showing high or low depressive symptomatology. LIMITATIONS, REASONS FOR CAUTION: Due to the cross-sectional design of this study and the small sample size in the depression groups, the findings should be interpreted with caution. WIDER IMPLICATIONS OF THE FINDINGS: Specialized psychological support should be available for ART men screened with high depressive symptomatology as part of routine prenatal care appointments.This study was conducted at Psychology Research Centre (UID/PSI/ 01662/2013), University of Minho, and at the Unidade de Investigação em Epidemiologia—Instituto de SaĂșde PĂșblica da Universidade do Porto (EPIUnit) (UID/DTP/04750/2013). It was supported by the Foundation for Science and Technology (Portuguese Ministry of Education and Science) through National funds and co-financed by FEDER through COMPETE2020 under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007653) and through the Operational Programme Factors of Competitiveness–COMPETE within the project ‘Health, Governance and Accountability in Embryo Research: Couples’ Decisions About the Fates of Embryos’ (FCOMP-01-0124-FEDER-014453), the FCT Investigator contract IF/01674/2015 and PhD grants (SFRH/BD/115048/2016, SFRH/BD/75807/2011 and SFRH/BD/40146/2007).info:eu-repo/semantics/publishedVersio
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