26 research outputs found
Foncteur de Picard d'un champ alg\'ebrique
In this article we study the Picard functor and the Picard stack of an
algebraic stack. We give a new and direct proof of the representability of the
Picard stack. We prove that it is quasi-separated, and that the connected
component of the identity is proper when the fibers of the stack are
geometrically normal. We study some examples of Picard functors of classical
stacks. In an appendix, we review the lisse-etale cohomology of abelian sheaves
on an algebraic stack
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Multi-lingual and multi-cultural information literacy; perspectives, models and good practice
Purpose
This paper reviews current approaches to, and good practice, in information literacy development in multi-lingual and multi-cultural settings, with particular emphasis on provision for international students.
Design/methodology/approach
A selective and critical review of published literature is extended by evaluation of examples of multi-lingual information literacy tutorials and MOOCs.
Findings
Multi-lingual and multi-cultural information literacy are umbrella terms covering a variety of situations and issues. This provision is of increasing importance in an increasingly mobile and multi-cultural world. This article evaluates current approaches and good practice, focusing on issues of culture vis a vis language, the balance between individual and group needs, specific and generic information literacy instruction, and models for information literacy, pedagogy and culture. Recommendations for good practice and for further research are given,
Originality/value
This is one of very few articles critically reviewing how information literacy development is affected by linguistic and cultural factors
The global meningitis genome partnership.
Genomic surveillance of bacterial meningitis pathogens is essential for effective disease control globally, enabling identification of emerging and expanding strains and consequent public health interventions. While there has been a rise in the use of whole genome sequencing, this has been driven predominately by a subset of countries with adequate capacity and resources. Global capacity to participate in surveillance needs to be expanded, particularly in low and middle-income countries with high disease burdens. In light of this, the WHO-led collaboration, Defeating Meningitis by 2030 Global Roadmap, has called for the establishment of a Global Meningitis Genome Partnership that links resources for: N. meningitidis (Nm), S. pneumoniae (Sp), H. influenzae (Hi) and S. agalactiae (Sa) to improve worldwide co-ordination of strain identification and tracking. Existing platforms containing relevant genomes include: PubMLST: Nm (31,622), Sp (15,132), Hi (1935), Sa (9026); The Wellcome Sanger Institute: Nm (13,711), Sp (>Â 24,000), Sa (6200), Hi (1738); and BMGAP: Nm (8785), Hi (2030). A steering group is being established to coordinate the initiative and encourage high-quality data curation. Next steps include: developing guidelines on open-access sharing of genomic data; defining a core set of metadata; and facilitating development of user-friendly interfaces that represent publicly available data
Coscinolactams A and B : new nitrogen-containing sesterterpenoids from the marine sponge Coscinoderma mathewsi exerting anti-inflammatory properties
Investigation of the marine sponge Coscinoderma mathewsi led to the isolation of two novel nitrogen-containing cheilanthane sesterterpenoids, coscinolactams A and B, together with known suvanine. The structures were elucidated by extensive spectroscopic measurements including NOE experiments to deduce the stereochemistry. The natural compounds, as well as a semisynthetic derivative, showed moderate anti-inflammatory activity measured as their capability to inhibit PGE2 and NO production. The suvanine aldehyde derivative 4 inhibited inducible nitric oxide protein expression with an IC50 value of 7.3 ÎĽM
Temperature-dependent VNIR spectroscopy of hydrated Mg-sulfates
International audienceWe investigate two poly-hydrated magnesium sulfates, hexahydrite (MgSO 4 • 6H 2 O) and epsomite (MgSO 4 • 7H 2 O), in the visible and infrared (VNIR) spectral range 0.5÷4.0 µm, as particulate for three different grain size ranges: 20-50 µm, 75-100 µm and 125-150 µm. All samples were measured in the 93 K to 298 K temperature range. The spectra of these hydrated salts are characterized by strong OH absorption bands in the 1.0-1.5 µm region, and by H 2 O absorption bands near 2 and 3 µm. Other weak features show up at low temperatures near 1.75 µm (in both hexahydrite and epsomite) and 2.2 µm (only in hexahydrite). The spectral behavior of the absorption bands of these two minerals has been analyzed as a function of both grain size and temperature, deriving trends related to specific spectral parameters such as band center, band depth, band area, and band width. Hydrated minerals, in particular mono-and poly-hydrated sulfates, are present in planetary objects such as Mars and the icy Galilean satellites. Safe detection of these minerals shall rely on detailed laboratory investigation of these materials in different environmental conditions. Hence an accurate spectral analysis of such minerals as a function of temperature is key to better understand and constrain future observations