920 research outputs found

    ARES+MOOG - a practical overview of an EW method to derive stellar parameters

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    The goal of this document is to describe the important practical aspects in the use of an Equivalent Width (EW) method for the derivation of spectroscopic stellar parameters. A general description of the fundamental steps composing any EW method is given, together with possible differences that may be found in different methods used in the literature. Then ARES+MOOG is then used as an example where each step of the method is described in detail. A special focus is given for the specific steps of this method, namely the use of a differential analysis to define the atomic data for the adopted line list, the automatic EW determinations, and the way to find the best parameters at the end of the procedure. Finally, a practical tutorial is given, where we focus on simple exercises useful to illustrate and explain the dependence of the abundances with the assumed stellar parameters. The interdependences are described and a clear procedure is given to find the "final" stellar parameters.Comment: 15 pages, 4 figures, accepted for publication as a chapter in "Determination of Atmospheric Parameters of B, A, F and G Type Stars", Springer (2014), eds. E. Niemczura, B. Smalley, W. Pyc

    Clec9a-mediated ablation of conventional dendritic cells suggests a lymphoid path to generating dendritic cells In Vivo

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    Conventional dendritic cells (cDCs) are versatile activators of immune responses that develop as part of the myeloid lineage downstream of hematopoietic stem cells. We have recently shown that in mice precursors of cDCs, but not of other leukocytes, are marked by expression of DNGR-1/CLEC9A. To genetically deplete DNGR-1-expressing cDC precursors and their progeny, we crossed Clec9a-Cre mice to Rosa-lox-STOP-lox-diphtheria toxin (DTA) mice. These mice develop signs of age-dependent myeloproliferative disease, as has been observed in other DC-deficient mouse models. However, despite efficient depletion of cDC progenitors in these mice, cells with phenotypic characteristics of cDCs populate the spleen. These cells are functionally and transcriptionally similar to cDCs in wild type control mice but show somatic rearrangements of Ig-heavy chain genes, characteristic of lymphoid origin cells. Our studies reveal a previously unappreciated developmental heterogeneity of cDCs and suggest that the lymphoid lineage can generate cells with features of cDCs when myeloid cDC progenitors are impaired

    Enhanced lithium depletion in Sun-like stars with orbiting planets

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    The surface abundance of lithium on the Sun is 140 times less than protosolar, yet the temperature at the base of the surface convective zone is not hot enough to burn Li. A large range of Li abundances in solar type stars of the same age, mass and metallicity is observed, but theoretically difficult to understand. An earlier suggestion that Li is more depleted in stars with planets was weakened by the lack of a proper comparison sample of stars without detected planets. Here we report Li abundances for an unbiased sample of solar-analogue stars with and without detected planets. We find that the planet-bearing stars have less than 1 per cent of the primordial Li abundance, while about 50 per cent of the solar analogues without detected planets have on average 10 times more Li. The presence of planets may increase the amount of mixing and deepen the convective zone to such an extent that the Li can be burned.Comment: 13 pages, 2 figure

    Loss of secreted gelsolin enhances response to anticancer therapies

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    Type 1 conventional dendritic cells (cDC1) play a critical role in priming anticancer cytotoxic CD8+ T cells. DNGR-1 (a.k.a. CLEC9A) is a cDC1 receptor that binds to F-actin exposed on necrotic cancer and normal cells. DNGR-1 signaling enhances cross-presentation of dead-cell associated antigens, including tumor antigens. We have recently shown that secreted gelsolin (sGSN), a plasma protein, competes with DNGR-1 for binding to dead cell-exposed F-actin and dampens anticancer immunity. Here, we investigated the effects of loss of sGSN on various anticancer therapies that are thought to induce cell death and provoke an immune response to cancer. We compared WT (wildtype) with Rag1-/- , Batf3-/- , Clec9agfp/gfp , sGsn-/- or sGsn-/- Clec9agfp/gfp mice implanted with transplantable tumor cell lines, including MCA-205 fibrosarcoma, 5555 BrafV600E melanoma and B16-F10 LifeAct (LA)-ovalbumin (OVA)-mCherry melanoma. Tumor-bearing mice were treated with (1) doxorubicin (intratumoral) chemotherapy for MCA-205, (2) BRAF-inhibitor PLX4720 (oral gavage) targeted therapy for 5555 BrafV600E, and (3) X-ray radiotherapy for B16 LA-OVA-mCherry. We confirmed that efficient tumor control following each therapy requires an immunocompetent host as efficacy was markedly reduced in Rag1-/- compared with WT mice. Notably, across all the therapeutic modalities, loss of sGSN significantly enhanced tumor control compared with treated WT controls. This was an on-target effect as mice deficient in both sGSN and DNGR-1 behaved no differently from WT mice following therapy. In sum, we find that mice deficient in sGsn display enhanced DNGR-1-dependent responsiveness to chemotherapy, targeted therapy and radiotherapy. Our findings are consistent with the notion some cancer therapies induce immunogenic cell death (ICD), which mobilizes anticancer T cells. Our results point to cDC1 and DNGR-1 as decoders of ICD and to sGSN as a negative regulator of such decoding, highlighting sGSN as a possible target in cancer treatment. Further prospective studies are warranted to identify patients who may benefit most from inhibition of sGSN function

    Information Literacy Needs and Traits of Transfer Students [Poster]

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    Assessment in Action Poster Session, American Library Association Annual Conference, Orlando, Florida, June 25, 2016

    Planet Populations as a Function of Stellar Properties

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    Exoplanets around different types of stars provide a window into the diverse environments in which planets form. This chapter describes the observed relations between exoplanet populations and stellar properties and how they connect to planet formation in protoplanetary disks. Giant planets occur more frequently around more metal-rich and more massive stars. These findings support the core accretion theory of planet formation, in which the cores of giant planets form more rapidly in more metal-rich and more massive protoplanetary disks. Smaller planets, those with sizes roughly between Earth and Neptune, exhibit different scaling relations with stellar properties. These planets are found around stars with a wide range of metallicities and occur more frequently around lower mass stars. This indicates that planet formation takes place in a wide range of environments, yet it is not clear why planets form more efficiently around low mass stars. Going forward, exoplanet surveys targeting M dwarfs will characterize the exoplanet population around the lowest mass stars. In combination with ongoing stellar characterization, this will help us understand the formation of planets in a large range of environments.Comment: Accepted for Publication in the Handbook of Exoplanet

    Midday measurements of leaf water potential and stomatal conductance are highly correlated with daily water use of Thompson Seedless grapevines

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    A study was conducted to determine the relationship between midday measurements of vine water status and daily water use of grapevines measured with a weighing lysimeter. Water applications to the vines were terminated on August 24th for 9 days and again on September 14th for 22 days. Daily water use of the vines in the lysimeter (ETLYS) was approximately 40 L vine−1 (5.3 mm) prior to turning the pump off, and it decreased to 22.3 L vine−1 by September 2nd. Pre-dawn leaf water potential (ΨPD) and midday Ψl on August 24th were −0.075 and −0.76 MPa, respectively, with midday Ψl decreasing to −1.28 MPa on September 2nd. Leaf g s decreased from ~500 to ~200 mmol m−2 s−1 during the two dry-down periods. Midday measurements of g s and Ψl were significantly correlated with one another (r = 0.96) and both with ETLYS/ETo (r = ~0.9). The decreases in Ψl, g s, and ETLYS/ETo in this study were also a linear function of the decrease in volumetric soil water content. The results indicate that even modest water stress can greatly reduce grapevine water use and that short-term measures of vine water status taken at midday are a reflection of daily grapevine water us

    Assessing Adverse Events in Madeira Primary

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    In last three decades, several epidemiological studies have been developed in order to assess the magnitude, nature and type of adverse events (AEs). Most of these studies focus on hospital settings, where the activities are more standardised, but imultaneously more complex and involving higher risks. However, in the last years, there is a growing movement and strong evidence that point out the importance of studying other healthcare contexts, such as primary care and long-term care. In Portugal, studies on primary care setting are scarce and still in the early stages. In this article, the authors describe the AEs assessment in Portuguese Primary Health Care (PHC) units in Madeira Island/Portugal. This study was quantitative, cross-sectional, observational and analytical, with probability sampling. We quantify and analyse the AEs registered by healthcare providers using the APEAS-PT formulary. A link to the APEAS–PT form was sent to 520 healthcare professionals (111 specialist in Family Medicine, 27 medical students, 382 nurses) who worked in 32 PHC centres. These professionals identified and analysed 85 AEs and 42 incidents, which corresponds to a prevalence of 3.9 AEs per 10,000 visits,with a 95% confidence interval (CI) between 3.7 and 4 AE. Most of the AEs were preventable (96%). The most frequent causal factors of AEs were associated with medication (69%), health care provided to users (54%), communication (41%) and diagnosis (22%). This analysis of AEs in Madeira island PHC contributed to reinforce patient safety culture and to better understand quaternary prevention.info:eu-repo/semantics/publishedVersio
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