92 research outputs found

    Bianchi's classification of 3-dimensional Lie algebras revisited

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    We present Bianchi's proof on the classification of real (and complex) 33-dimensional Lie algebras in a coordinate free version from a strictly representation theoretic point of view. Nearby we also compute the automorphism groups and from this the orbit dimensions of the corresponding orbits in the algebraic variety X⊆Λ2V∗⊗VX\subseteq\Lambda^2V^*\otimes V describing all Lie brackets on a fixed vector space VV of dimension 33. Moreover we clarify which orbits lie in the closure of a given orbit and therefore the topology on the orbit space X/GX/G with G=Aut(V)G=\mathrm{Aut}(V)

    Vorwort

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    Vorwort zum Band 01 "Theorien!" der Schriftenreihe der TĂŒbingen School of Educatio

    Dimensionen fachwissenschaftlicher und fachdidaktischer Kompetenzen bei angehenden LehrkrÀften: Erkenntnisse zum VerhÀltnis beider Kompetenzformen aus den FÀchern Mathematik und Englisch

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    Dimensionen fachwissenschaftlicher und fachdidaktischer Kompetenzen bei angehenden LehrkrÀften: Erkenntnisse zum VerhÀltnis beider Kompetenzformen aus den FÀchern Mathematik und Englisc

    Veröffentlichungen aus dem Staatsarchiv der Freien und Hansestadt Hamburg

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    Das Staatsarchiv Hamburg feierte 2010 sein 300-jÀhriges Bestehen. Sein VorlÀufer wurde bereits im Jahre 1293 erstmals erwÀhnt und somit die Aufbewahrung wichtiger Dokumente der Stadt an zentraler Stelle bezeugt. Doch erst seit dem 11. September 1710, dem Amtsantritt von Nicolaus Stampeel als wissenschaftlicher Archivar bei der Stadt Hamburg, werden Dokumente systematisch ausgewÀhlt, bewahrt und erschlossen. Dieses JubilÀum hat das Staatsarchiv mit einem breit gefÀcherten Veranstaltungsprogramm begangen, zu dem auch VortrÀge und Lesungen gehörten, die in der hier vorliegenden Festschrift abgedruckt sind.In 2010, the Hamburg State Archives celebrated its 300th anniversary. The Archives\u27 forerunner was first mentioned in 1293 and thus testified to the preservation of important documents of the city in a central place. But it was not until September 11th, 1710, when Nicolaus Stampeel took office as a scientific archivist at the City of Hamburg. From then on, documents were systematically selected, preserved and indexed. This anniversary was celebrated by the State Archives with a broad programme of events, which included lectures and readings printed in the commemorative volume available here

    Sarbecoviruses of British Horseshoe Bats; Sequence Variation and Epidemiology

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    Horseshoe bats are the natural hosts of the Sarbecovirus subgenus that includes SARS-CoV and SARS-CoV- 2. Despite the devastating impact of the COVID-19 pandemic, there is still little known about the underlying epidemiology and virology of sarbecoviruses in their natural hosts, leaving large gaps in our pandemic preparedness. Here we describe the results of PCR testing for sarbecoviruses in the two horseshoe bat species (Rhinolophus hipposideros and R. ferrumequinum) present in Great Britain, collected in 2021–22 during the peak of COVID-19 pandemic. One hundred and ninety seven R. hipposideros samples from 33 roost sites and 277 R. ferrumequinum samples from 20 roost sites were tested. No coronaviruses were detected in any samples from R. ferrumequinum whereas 44 and 56 % of individual and pooled (respectively) faecal samples from R. hipposideros across multiple roost sites tested positive in a sarbecovirus-specific qPCR. Full genome sequences were generated from three of the positive samples (and partial genomes from two more) using Illumina RNAseq on unenriched samples. Phylogenetic analyses showed that the obtained sequences belong to the same monophyletic clade, with >95 % similarity to previously-reported European isolates from R. hipposideros. The sequences differed in the presence or absence of accessory genes ORF 7b, 9b and 10. All lacked the furin cleavage site of SARS-CoV-2 spike gene and are therefore unlikely to be infective for humans. These results demonstrate a lack, or at least low incidence, of SARS-CoV-2 spill over from humans to susceptible GB bats, and confirm that sarbecovirus infection is widespread in R. hipposideros. Despite frequently sharing roost sites with R. ferrumequinum, no evidence of cross-species transmission was found

    Apercal-The Apertif calibration pipeline

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    Apertif (APERture Tile In Focus) is one of the Square Kilometre Array (SKA) pathfinder facilities. The Apertif project is an upgrade to the 50-year-old Westerbork Synthesis Radio Telescope (WSRT) using phased-array feed technology. The new receivers create 40 individual beams on the sky, achieving an instantaneous sky coverage of 6.5 square degrees. The primary goal of the Apertif Imaging Survey is to perform a wide survey of 3500 square degrees (AWES) and a medium deep survey of 350 square degrees (AMES) of neutral atomic hydrogen (up to a redshift of 0.26), radio continuum emission and polarisation. Each survey pointing yields 4.6 TB of correlated data. The goal of Apercal is to process this data and fully automatically generate science ready data products for the astronomical community while keeping up with the survey observations. We make use of common astronomical software packages in combination with Python based routines and parallelisation. We use an object oriented module-based approach to ensure easy adaptation of the pipeline. A Jupyter notebook based framework allows user interaction and execution of individual modules as well as a full automatic processing of a complete survey observation. If nothing interrupts processing, we are able to reduce a single pointing survey observation on our five node cluster with 24 physical cores and 256 GB of memory each within 24 h keeping up with the speed of the surveys. The quality of the generated images is sufficient for scientific usage for 44% of the recorded data products with single images reaching dynamic ranges of several thousands. Future improvements will increase this percentage to over 80%. Our design allowed development of the pipeline in parallel to the commissioning of the Apertif system
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