On the possibility of a long subglacial river under the north Greenland ice sheet

The Tenth Symposium on Polar Science/Ordinary sessions: [OM] Polar Meteorology and Glaciology, Wed. 4 Dec. / 2F Auditorium, National Institute of Polar Researc

Adaptation of genetically monomorphic bacteria: evolution of copper resistance through multiple horizontal gene transfers of complex and versatile mobile genetic elements

Copper-based antimicrobial compounds are widely used to control plant bacterial pathogens. Pathogens have adapted in response to this selective pressure. Xanthomonas citri pv. citri, a major citrus pathogen causing Asiatic citrus canker, was first reported to carry plasmid-encoded copper resistance in Argentina. This phenotype was conferred by the copLAB gene system. The emergence of resistant strains has since been reported in Réunion and Martinique. Using microsatellite-based genotyping and copLAB PCR, we demonstrated that the genetic structure of the copper-resistant strains from these three regions was made up of two distant clusters and varied for the detection of copLAB amplicons. In order to investigate this pattern more closely, we sequenced six copper-resistant X. citri pv. citri strains from Argentina, Martinique and Réunion, together with reference copper-resistant Xanthomonas and Stenotrophomonas strains using long-read sequencing technology. Genes involved in copper resistance were found to be strain-dependent with the novel identification in X. citri pv. citri of copABCD and a cus heavy metal efflux resistance-nodulation-division system. The genes providing the adaptive trait were part of a mobile genetic element similar to Tn3-like transposons and included in a conjugative plasmid. This indicates the system's great versatility. The mining of all available bacterial genomes suggested that, within the bacterial community, the spread of copper resistance associated to mobile elements and their plasmid environments was primarily restricted to the Xanthomonadaceae family

A new approach to meteorological observations on remote polar glaciers using open-source internet of things technologies

Key regions of the world lack sufficient infrastructure to collect geophysical observations, often due to logistical challenges such as difficult accessibility and cost. With the advent of Internet-of-Things (IoT) technologies and low-cost electronics, it is possible today to build monitoring systems collecting spatially distributed, in-situ data with real-time connectivity to online servers for immediate and long-term usage at costs comparable to those of a single autonomous weather station. We present here a custom-built, modular system that collects quality data, and, that is, robust to adverse meteorological conditions and lack of energy. It integrates commercial and custom-built sensors connected to a node (main device) that manages power, data and radio communication. Data is sent to gateways and then to a server that parses, stores and quality controls the data. We deployed two networks in the vicinity of Ny-Ålesund in Svalbard, and operated from May 2021 to April 2022 to measure meteorological and glaciological variables. Our system collected reliable data and had sufficient power resources to survive 4–5 months of darkness during the polar night. Here, we present the design considerations and performance metrics, report our lessons learned from this challenging deployment, and suggest pathways for future improvements

High Mountain Areas

The cryosphere (including, snow, glaciers, permafrost, lake and river ice) is an integral element of high-mountain regions, which are home to roughly 10% of the global population. Widespread cryosphere changes affect physical, biological and human systems in the mountains and surrounding lowlands, with impacts evident even in the ocean. Building on the IPCC’s Fifth Assessment Report (AR5), this chapter assesses new evidence on observed recent and projected changes in the mountain cryosphere as well as associated impacts, risks and adaptation measures related to natural and human systems. Impacts in response to climate changes independently of changes in the cryosphere are not assessed in this chapter. Polar mountains are included in Chapter 3, except those in Alaska and adjacent Yukon, Iceland, and Scandinavia, which are included in this chapter

Les associations de copropriétaires

Lefeuvre Marie-Pierre. Les associations de copropriétaires. In: Les Annales de la recherche urbaine, N°89, 2001. Le foisonnement associatif. pp. 140-141

TRAVAIL DE LA PROPRIETE ET PRODUCTION DE L’ESPACE

International audienceLa littérature sur le patrimoine des ménages braque le regard sur deux grandes évolutions : l'accroissement global de leur patrimoine (notamment immobilier), sa financiarisation, et, accessoirement, le fait que ces deux tendances accentuent les inégalités sociales. Je débuterai mon propos en donnant un aperçu de ces deux évolutions. Je dirai ensuite pourquoi, à mon sens, cette vision étroitement économique est réductrice : elle donne à penser que la différence entre le patrimoine des plus riches et celui des plus pauvres est seulement quantitative et que la propriété a pour tous un sens univoque. Or le rapport à la propriété varie intensément d'une classe sociale à l'autre. Ce qui contribue, probablement, à remodeler les identités de classes.Pour saisir le rapport que les individus entretiennent à leur propriété, je pense que le terme de travail peut être utile. En m'appuyant sur plusieurs recherches, je montrerai que les propriétaires « travaillent leur propriété » et peuvent être conduits à « travailler avec leur propriété ». Le terme « travail » vient notamment souligner la porosité entre activité professionnelle et activités relatives à la propriété.Je conclurai mon propos en essayant de montrer que l'idée de « travail de la propriété » peut constituer un apport aux réflexions sur la production de l'espace

Faire métropole. De nouvelles règles du jeu ?

International audienc