1,698 research outputs found

    The VizieR database of Astronomical Catalogues

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    VizieR is a database grouping in an homogeneous way thousands of astronomical catalogues gathered since decades by the Centre de Donnees de Strasbourg (CDS) and participating institutes. The history and current status of this large collection is briefly presented, and the way these catalogues are being standardized to fit in the VizieR system is described. The architecture of the database is then presented, with emphasis on the management of links and of accesses to very large catalogues. Several query interfaces are currently available, making use of the ASU protocol, for browsing purposes or for use by other data processing systems such as visualisation tools.Comment: 10 pages, 2 Postscript figures; to be published in A&A

    Southern Durchmusterung (Schoenfeld 1886): Documentation for the machine-readable version

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    The machine-readable version of the catalog, as it is currently being distributed from the Astronomical Data Center, is described. The Southern Durchmusterung (SD) was computerized at the Centre de Donnees Astronomiques de Strasbourg and at the Astronomical Data Center at the National Space Science Data Center, NASA/Goddard Space Flight Center. Corrigenda listed in the original SD volume and published by Kuenster and Sticker were incorporated into the machine file. In addition, one star indicated to be missing in a published list, and later verified, is flagged so that it can be omitted from computer plotted charts if desired. Stars deleted in the various errata lists were similarly flagged, while those with revised data are flagged and listed in a separate table. This catalog covers the zones -02 to -23 degrees; zones +89 to -01 degrees (the Bonner Durchmusterung) are included in a separate catalog available in machine-readable form

    Immunological ignorance of solid tumors

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    Many peripheral solid tumors such as sarcomas and carcinomas express tumor-specific antigens that can serve as targets for immune effector T cells. Nevertheless, the immune surveillance against clinically manifest carcinomas and sarcomas seems relatively inefficient. NaĂŻve cytotoxic T cells are activated exclusively in secondary lymphoid organs including the spleen and lymph nodes. Tumor antigen might be either cross-presented to naĂŻve cytotoxic T cells by professional antigen-presenting cells (pAPC), or presented directly by tumor cells that migrated to secondary lymphoid organs. Direct priming is quite inefficient during early tumor development because metastasis to lymphoid organs is usually limited to advanced stage diseases. Similarly, the process of cross-priming by pAPC seems to depend on relatively large antigen amounts and on maturation stimuli for dendritic cells, and both requirements may be limiting during initial tumorigenesis. Therefore, the immunosurveillance of solid tumors may fail because they are ignored for too long by the immune system. However, these situations may prove promising for the induction of tumor-specific T cell immunity by vaccination, as the T cell repertoire against these antigens has a naĂŻve phenotype and is not yet affected by tolerance mechanism

    Invasive intrauterine Therapie

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    Zusammenfassung: Einige fetale Fehlbildungen führen bereits intrauterin zu Organschäden, die postpartal schwere bleibende Behinderungen zur Folge haben oder nicht mit dem Leben vereinbar sind. Fetale Eingriffe verlangen eine sichere pränatale Diagnosestellung, Ausschluss assoziierter Fehlbildungen, Reversibilität der schädlichen Krankheitseffekte und deutliche Verbesserung der Prognose durch den fetalen Eingriff an dafür spezialisierten multidisziplinären Therapiezentren. In der invasiven fetalen Therapie wird sowohl offen, wie bei der fetalen Myelomeningozelen(MMC)-Operation, als auch fetoskopisch operiert. Zu nennen sind z.B. die reversible fetoskopische Balloneinlage in die Trachea zur Stimulation des Lungenwachstums bei der kongenitalen Zwerchfellhernie des Feten mit schwerer Lungenhypoplasie oder die Laserkoagulation plazentarer Gefäßverbindungen zum Stopp eines unausgeglichenen Blutflusses beim fetofetalen Transfusionssyndrom (FFTS). Hauptkomplikation der fetalen Chirurgie ist der vorzeitige Blasensprun

    Pushing the limits of magnetic anisotropy in trigonal bipyramidal Ni(II)

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    Monometallic complexes based on 3d transition metal ions in certain axial coordination environments can exhibit appreciably enhanced magnetic anisotropy, important for memory applications, due to stabilisation of an unquenched orbital moment. For high-spin trigonal bipyramidal Ni(II), if competing structural distortions can be minimised, this may result in an axial anisotropy that is at least an order of magnitude stronger than found for orbitally non-degenerate octahedral complexes. Broadband, high-field EPR studies of [Ni(MDABCO)2Cl3]ClO4 (1) confirm an unprecedented axial magnetic anisotropy, which pushes the limits of the familiar spin-only description. Crucially, compared to complexes with multidentate ligands that encapsulate the metal ion, we see only a very small degree of axial symmetry breaking. 1 displays field-induced slow magnetic relaxation, which is rare for monometallic Ni(II) complexes due to efficient spin–lattice and quantum tunnelling relaxation pathways

    IVOA Recommendation: An IVOA Standard for Unified Content Descriptors Version 1.1

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    This document describes the current understanding of the IVOA controlled vocabulary for describing astronomical data quantities, called Unified Content Descriptors (UCDs). The present document defines a new standard (named UCD1+) improving the first generation of UCDs (hereafter UCD1). The basic idea is to adopt a new syntax and vocabulary requiring little effort for people to adapt softwares already using UCD1. This document also addresses the questions of maintenance and evolution of the UCD1+. Examples of use cases within the VO, and tools for using UCD1+ are also described

    IVOA Recommendation: VOTable Format Definition Version 1.3

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    This document describes the structures making up the VOTable standard. The main part of this document describes the adopted part of the VOTable standard; it is followed by appendices presenting extensions which have been proposed and/or discussed, but which are not part of the standard

    Epigenetic Silencing of Immune-Checkpoint Receptors in Bone Marrow- Infiltrating T Cells in Acute Myeloid Leukemia.

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    Background Immune-checkpoint (IC) inhibitors have revolutionized the treatment of multiple solid tumors and defined lymphomas, but they are largely ineffective in acute myeloid leukemia (AML). The reason why especially PD1/PD-L1 blocking agents are not efficacious is not well-understood but it may be due to the contribution of different IC ligand/receptor interactions that determine the function of T cells in AML. Methods To analyze the interactions of IC ligands and receptors in AML, we performed a comprehensive transcriptomic analysis of FACS-purified leukemia stem/progenitor cells and paired bone marrow (BM)-infiltrating CD4+ and CD8+ T cells from 30 patients with AML. The gene expression profiles of activating and inhibiting IC ligands and receptors were correlated with the clinical data. Epigenetic mechanisms were studied by inhibiting the histone deacetylase with valproic acid or by gene silencing of PAC1. Results We observed that IC ligands and receptors were mainly upregulated in leukemia stem cells. The gene expression of activating IC ligands and receptors correlated with improved prognosis and vice versa. In contrast, the majority of IC receptor genes were downregulated in BM-infiltrating CD8+ T cells and partially in CD4+ T cells, due to pathological chromatin remodeling via histone deacetylation. Therefore, treatment with histone deacetylase inhibitor (HDACi) or silencing of PAC1, as a T cell-specific epigenetic modulator, significantly increased the expression of IC receptors and defined effector molecules in CD8+ T cells. Conclusions Our results suggest that CD8+ T cells in AML are dysfunctional mainly due to pathological epigenetic silencing of activating IC receptors rather than due to signaling by immune inhibitory IC receptors, which may explain the limited efficacy of antibodies that block immune-inhibitory ICs in AML
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