VVV J165507.19-421755.5: A Nearby T Dwarf Hidden in the Galactic Plane

© 2022. The Author(s). Published by the American Astronomical Society. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/We present the discovery of VVV J165507.19−421755.5, a mid-T dwarf found through ongoing unWISE-based proper motion searches. A near-infrared spectrum of this object obtained with the NIRES instrument on the Keck II telescope indicates a spectral classification of T5. Using data from the VISTA Variables in the Via Lactea (VVV) catalog with a 9 year baseline, we measure a proper motion of ( μαcos(δ) , μ δ ) = (−631.0 ± 1.3, −315.0 ± 1.4) mas yr−1 and a trigonometric parallax of π abs = 66.0 ± 4.8 mas, corresponding to a distance of 15.2 ± 1.1 pc. The trigonometric parallax agrees well with our photometric distance estimate (16.1 −3.9+5.1 pc) assuming that VVV J165507.19−421755.5 is a single T5 dwarf. VVV J165507.19−421755.5 is a new member of the 20 parsec census.Peer reviewe

Discovery of a Mid-L Dwarf Companion to the L 262-74 System

We present the discovery of CWISE J151044.74$-$524923.5, a wide low-mass companion to the nearby ($\sim$24.7 pc) system L 262-74, which was identified through the Backyard Worlds: Planet 9 citizen science project. We detail the properties of the system, and we assess that this companion is a mid-L dwarf, which will need to be verified spectroscopically. With an angular separation of 74\farcs3, we estimate a projected physical separation of $\sim$1837 au from the central system

WRAP: A Tool for Efficient Cross-Identification of Proper Motion Objects Spanning Multiple Surveys

We introduce the Wide-field Retrieval of Astrodata Program (WRAP), a tool created to aid astronomers in gathering photometric and astrometric data for point sources that may confuse simple cross-matching algorithms because of their faintness or motion. WRAP allows astronomers to correctly cross-identify objects with proper motion across multiple surveys by wedding the catalog data with its underlying images, thus providing visual confirmation of cross-associations in real time. Developed within the Backyard Worlds: Planet 9 citizen science project, WRAP aims to aid in the characterization of faint, high motion sources by this collaboration (and others).Comment: 4 pages, 1 figure, Github and DOI link to progra

The geopolitics of Boko Haram and Nigeria's ‘war on terror’

The April 2014 kidnapping of the schoolgirls at Chibok, north-eastern Nigeria, has meant that Boko Haram is now widely discussed by Western governments and in Western media. Yet within Nigeria the group has been well known for several years. Boko Haram's activities, or actions attributed to the group, have developed in a range of ways, many contradictory, including bombings, kidnappings of Europeans within Nigeria and neighbouring Cameroon, killing of medical personnel, and overtures for dialogue with the Federal Government. There are recurrent reports of links to Al Qaeda in the Islamic Maghreb, and in the past few years the United States has taken a much more active role in the region. Some of the wider geopolitical issues relate to the French-led intervention in Mali; a country to which Nigeria has also sent troops. This article tries to disentangle these different questions. It looks first at who Boko Haram are, and their history. It situates the group within the wider context of Nigerian politics, and to discuss the biopolitical and geopolitical elements of their operations and of the actions of the Nigerian security services and other actors towards them. It ends by relating what is happening within and beyond Nigeria to the wider context of the ‘war on terror’

Use of biologics for the management of Crohn's disease: IG-IBD clinical guidelines based on the GRADE methodology

A cure for Crohn's disease (CD), a chronic inflammatory disease of the gastrointestinal tract of unknown etiology, is not available, so patients require lifelong management to keep inflammation under control. The therapeutic armamentarium has expanded with approval of several biological drugs, including in-fliximab, adalimumab, vedolizumab and ustekinumab - monoclonal antibodies that target different in-flammatory pathways - and darvadstrocel, a suspension of expanded human allogeneic, adipose-derived, mesenchymal stromal cells for the treatment of refractory complex perianal fistula. Notwithstanding ex-isting practice guidelines on medical therapy for CD, the Italian Group for the Study of Inflammatory Bowel Disease felt the need to issue new guidelines focused on the use of biologics for managing the intestinal manifestations of CD and based on the GRADE methodology. This document presents recom-mendations regarding six clinical settings, from the induction to the maintenance of clinical remission, and from optimization and de-escalation of treatments to dealing with perianal CD and post-operative recurrence. The 19 evidence-based statements are supported by information on the quality of the evi-dence, agreement rate among panel members, and panel comments mainly based on evidence from real world studies