89 research outputs found

    The Milky Way like galaxy NGC 6384 and its nuclear star cluster at high NIR spatial resolution using LBT/ARGOS commissioning data

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    We analyse high spatial resolution near infra-red (NIR) imaging of NGC6384, a Milky Way like galaxy, using ARGOS commissioning data at the Large Binocular Telescope (LBT). ARGOS provides a stable PSFFWHM ⁣= ⁣0.2" ⁣ ⁣0.3"_{\rm FWHM}\!=\!0.2"\!-\!0.3" AO correction of the ground layer across the LUCI2 NIR camera 4 ⁣×44'\!\times4' field by using six laser guide stars (three per telescope) and a natural guide star for tip-tilt sensing and guiding. Enabled by this high spatial resolution we analyse the structure of the nuclear star cluster (NSC) and the central kiloparsec of NGC6384. We find via 2D modelling that the NSC (reff ⁣ ⁣10r_{\rm eff}\!\simeq\!10pc) is surrounded by a small (reff ⁣ ⁣100r_{\rm eff}\!\simeq\!100pc) and a larger Sersi\'c (reff ⁣ ⁣400r_{\rm eff}\!\simeq\!400pc), all embedded within the NGC\,6384 large-scale boxy/X-shaped bulge and disk. This proof-of-concept study shows that with the high spatial resolution achieved by ground-layer AO we can push such analysis to distances previously only accessible from space. SED-fitting to the NIR and optical HST photometry allowed to leverage the age-metallicity-extinction degeneracies and derive the effective NSC properties of an young to old population mass ratio of 8%8\% with M,old ⁣ ⁣3.5×107M{\cal M}_{\rm\star,old}\!\simeq\!3.5\times10^7M_\odot, Age$_{\rm old,\ young}\!=\!10.9\pm1.3Gyrand226MyrGyr and 226\,Myr \pm62\%,metallicity[M/H], metallicity [M/H]=\!-0.11\pm0.16and and 0.33\pm39\%dex,anddex, and E(B\!-\!V)\!=\!0.63$ and 1.44mag.Comment: 12 pages (+9 appendix), 11 figures, Accepted in MNRA

    Post-traumatic-stress in the context of childhood maltreatment: pathways from attachment through mentalizing during the transition to parenthood

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    INTRODUCTION: This study aimed to clarify the role of mentalizing in pathways from attachment to Post Traumatic Stress Symptoms (PTSS) in survivors of childhood maltreatment (CM). We focused on the transition to parenting, a critical period for reworking parenting representations to reduce intergenerational maltreatment cycles. METHOD: Study participants included 100 pregnant CM survivors. We assessed PTSS with the SCID and attachment and mentalizing with the Adult Attachment Interview (AAI), which was rated for Attachment and Reflective Functioning (RF). RESULTS: Regarding Re-experiencing trauma symptoms, the results of the path analysis were consistent with mediation. CM survivors' mentalizing about their early relationships with their parents (RF-Other) directly impacted Re-experiencing trauma symptoms, and attachment had an effect on Re-experiencing trauma symptoms through mentalizing (RF-Other). Regarding Arousal/Reactivity symptoms, the results of the pathways analysis were consistent with partial mediation by mentalizing about early relationships with parents (RF-Other). In addition to the pathway from attachment via mentalizing (RF-Other) to Arousal/Reactivity, the pathway between attachment and Arousal/Reactivity also remained significant. DISCUSSION: This study provides new evidence of a mentalizing and attachment model of PTSS in CM survivors. The findings indicate that increased mentalizing about early relationships with parents is an important process associated with lower PTSS. Finally, we discuss the implications of developing interventions for CM survivors to reduce PTSS. Scaffolding the development of mentalizing regarding attachment relationships in which CM occurred may help CM survivors reduce the intrusion of traumatic memories and decrease trauma-related arousal and reactivity symptoms. Interventions to help CM survivors mentalize regarding parents and attachment relationships in which trauma occurred may be particularly important during the transition to parenting when activation of representations of parenting can trigger PTSS

    Maternal and Child Sexual Abuse History: An Intergenerational Exploration of Children’s Adjustment and Maternal Trauma-Reflective Functioning

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    Objective: The aim of the current study was to investigate associations, unique and interactive, between mothers’ and children’s histories of childhood sexual abuse (CSA) and children’s psychiatric outcomes using an intergenerational perspective. Further, we were particularly interested in examining whether maternal reflective functioning about their own trauma (T-RF) was associated with a lower likelihood of children’s abuse exposure (among children of CSA-exposed mothers).Methods: One hundred and eleven children (Mage = 9.53 years; 43 sexual abuse victims) and their mothers (Mage = 37.99; 63 sexual abuse victims) participated in this study. Mothers completed the Parent Development Interview (PDI), which yielded assessments of RF regarding their own experiences of abuse, and also reported on their children’s internalizing and externalizing symptoms.Results: Children of CSA-exposed mothers were more likely to have experienced CSA. A key result was that among CSA-exposed mothers, higher maternal T-RF regarding their own abuse was associated with lower likelihood of child CSA-exposure. Mothers’ and children’s CSA histories predicted children’s internalizing and externalizing symptoms, such that CSA exposure for mother or child was associated with greater symptomatology in children.Conclusion: The findings show that the presence of either maternal or child CSA is associated with more child psychological difficulties. Importantly in terms of identifying potential protective factors, maternal T-RF is associated with lower likelihood of CSA exposure in children of CSA-exposed mothers. We discuss these findings in the context of the need for treatments focusing on increasing T-RF in mothers and children in the context of abuse to facilitate adaptation and reduce the intergenerational risk

    School-Aged Children With Higher Reflective Functioning Exhibit Lower Cardiovascular Reactivity

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    Despite extensive theorizing regarding the regulatory role of reflective functioning (RF), few studies have explored the links between RF and physiological indices of emotion regulation, and none have examined these associations in children. Further, while scholars contend that RF promotes resilience via enhanced ability to process emotional experiences, including those occurring in attachment relationships, this argument has seldom been tested empirically in children. In the current study, we explore the association between RF and physiological measures of emotion reactivity and regulation, as well as the interaction of RF and attachment insecurity. We test these associations by examining children's (N = 76; 8–12 years old) cardiovascular responses [respiratory sinus arrhythmia (RSA)] to a standardized paradigm designed to evoke reactions regarding the experience and expression of attachment-related needs. Children also completed a semi-structured attachment interview, which was later coded for children's attachment insecurity (operationalized as attachment dismissal and preoccupation) and RF. Our findings were largely consistent with theory and our hypotheses, suggesting that higher RF is associated with lesser cardiovascular reactivity (higher levels of RSA) during the stressor task and better recovery following the task. These links were especially strong for children with greater attachment preoccupation but did not vary as a function of children's levels of attachment dismissal. These findings contribute to developmental theory in suggesting that RF is closely linked to physiological emotion regulation in children

    Gamma-Linolenic Acid Levels Correlate with Clinical Efficacy of Evening Primrose Oil in Patients with Atopic Dermatitis

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    Introduction: Atopic dermatitis (AD) has been related to a deficiency of delta-6-desaturase, an enzyme responsible for the conversion of linoleic acid to gamma-linolenic acid (GLA). Evening primrose oil (EPO) contains high amounts of GLA. Therefore, this study investigated whether EPO supplementation results in an increase in plasma GLA and its metabolite dihomo-gamma-linolenic acid (DGLA) correlating with clinical improvement of AD, assessed by the SCORing Atopic Dermatitis (SCORAD) index. Methods: The open study included 21 patients with AD. EPO (4-6g) was administered daily for 12weeks. Before treatment, and 4 and 12weeks after initiation of EPO supplementation, objective SCORAD was assessed and plasma concentrations of GLA and DGLA were determined by gas chromatography. Results: A significant increase in plasma GLA and DGLA levels and a decrease in the objective SCORAD were observed 4 and 12weeks after initiation of EPO treatment. In the per-protocol population (n=14), a significant inverse correlation between the changes in plasma GLA levels and SCORAD was found (P=0.008). Conclusion: The clinical disease activity under EPO treatment correlates with the individual increase in plasma GLA levels. Thus, the results of this pilot study indicate that an increase in plasma GLA might be used as predictive parameter for responsiveness of AD to EPO therapy

    LBT/ARGOS adaptive optics observations of z2\sim 2 lensed galaxies

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    Gravitationally lensed systems allow a detailed view of galaxies at high redshift. High spatial- and spectral-resolution measurements of arc-like structures can offer unique constraints on the physical and dynamical properties of high-z systems. We present near-infrared spectra centred on the gravitational arcs of six known z ~ 2 lensed star-forming galaxies of stellar masses of 10^9-10^11 Msun and star formation rate (SFR) in the range between 10 and 400 Msun/yr. Ground layer adaptive optics (AO)-assisted observations are obtained at the Large Binocular Telescope (LBT) with the LUCI spectrographs during the commissioning of the ARGOS facility. We used MOS masks with curved slits to follow the extended arched structures and study the diagnostic emission lines. Combining spatially resolved kinematic properties across the arc-like morphologies, emission line diagnostics and archival information, we distinguish between merging and rotationally supported systems, and reveal the possible presence of ejected gas. For galaxies that have evidence for outflows, we derive outflow energetics and mass-loading factors compatible with those observed for stellar winds in local and high-z galaxies. We also use flux ratio diagnostics to derive gas-phase metallicities. The low signal-to-noise ratio in the faint Hβ\beta and nitrogen lines allows us to derive an upper limit of ~ 0.15 dex for the spatial variations in metallicity along the slit for the lensed galaxy J1038. Analysed near-infrared spectra presented here represent the first scientific demonstration of performing AO-assisted multi-object spectroscopy with narrow curved-shape slits. The increased angular and spectral resolution, combined with the binocular operation mode with the 8.4-m-wide eyes of LBT, will allow the characterisation of kinematic and chemical properties of a large sample of galaxies at high-z in the near future.Comment: 18 pages, 13 figures, accepted for publication in A&

    ARGOS: the laser guide star system for the LBT

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    ARGOS is the Laser Guide Star adaptive optics system for the Large Binocular Telescope. Aiming for a wide field adaptive optics correction, ARGOS will equip both sides of LBT with a multi laser beacon system and corresponding wavefront sensors, driving LBT's adaptive secondary mirrors. Utilizing high power pulsed green lasers the artificial beacons are generated via Rayleigh scattering in earth's atmosphere. ARGOS will project a set of three guide stars above each of LBT's mirrors in a wide constellation. The returning scattered light, sensitive particular to the turbulence close to ground, is detected in a gated wavefront sensor system. Measuring and correcting the ground layers of the optical distortions enables ARGOS to achieve a correction over a very wide field of view. Taking advantage of this wide field correction, the science that can be done with the multi object spectrographs LUCIFER will be boosted by higher spatial resolution and strongly enhanced flux for spectroscopy. Apart from the wide field correction ARGOS delivers in its ground layer mode, we foresee a diffraction limited operation with a hybrid Sodium laser Rayleigh beacon combination.12 page(s

    European Atlas of Natural Radiation

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    Natural ionizing radiation is considered as the largest contributor to the collective effective dose received by the world population. The human population is continuously exposed to ionizing radiation from several natural sources that can be classified into two broad categories: high-energy cosmic rays incident on the Earth’s atmosphere and releasing secondary radiation (cosmic contribution); and radioactive nuclides generated during the formation of the Earth and still present in the Earth’s crust (terrestrial contribution). Terrestrial radioactivity is mostly produced by the uranium and thorium radioactive families together with potassium. In most circumstances, radon, a noble gas produced in the radioactive decay of uranium, is the most important contributor to the total dose. This Atlas aims to present the current state of knowledge of natural radioactivity, by giving general background information, and describing its various sources. This reference material is complemented by a collection of maps of Europe displaying the levels of natural radioactivity caused by different sources. It is a compilation of contributions and reviews received from more than 80 experts in their field: they come from universities, research centres, national and European authorities and international organizations. This Atlas provides reference material and makes harmonized datasets available to the scientific community and national competent authorities. In parallel, this Atlas may serve as a tool for the public to: • familiarize itself with natural radioactivity; • be informed about the levels of natural radioactivity caused by different sources; • have a more balanced view of the annual dose received by the world population, to which natural radioactivity is the largest contributor; • and make direct comparisons between doses from natural sources of ionizing radiation and those from man-made (artificial) ones, hence to better understand the latter.JRC.G.10-Knowledge for Nuclear Security and Safet
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