A conserved lysine residue of plant Whirly proteins is necessary for higher order protein assembly and protection against DNA damage

All organisms have evolved specialized DNA repair mechanisms in order to protect their genome against detrimental lesions such as DNA double-strand breaks. In plant organelles, these damages are repaired either through recombination or through a microhomology-mediated break-induced replication pathway. Whirly proteins are modulators of this second pathway in both chloroplasts and mitochondria. In this precise pathway, tetrameric Whirly proteins are believed to bind single-stranded DNA and prevent spurious annealing of resected DNA molecules with other regions in the genome. In this study, we add a new layer of complexity to this model by showing through atomic force microscopy that tetramers of the potato Whirly protein WHY2 further assemble into hexamers of tetramers, or 24-mers, upon binding long DNA molecules. This process depends on tetramer–tetramer interactions mediated by K67, a highly conserved residue among plant Whirly proteins. Mutation of this residue abolishes the formation of 24-mers without affecting the protein structure or the binding to short DNA molecules. Importantly, we show that an Arabidopsis Whirly protein mutated for this lysine is unable to rescue the sensitivity of a Whirly-less mutant plant to a DNA double-strand break inducing agent

Altimetry for the future: Building on 25 years of progress

In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and more recently, in 2018, in Ponta Delgada, Portugal, 25 Years of Progress in Radar Altimetry. On this latter occasion it was decided to collect contributions of scientists, engineers and managers involved in the worldwide altimetry community to depict the state of altimetry and propose recommendations for the altimetry of the future. This paper summarizes contributions and recommendations that were collected and provides guidance for future mission design, research activities, and sustainable operational radar altimetry data exploitation. Recommendations provided are fundamental for optimizing further scientific and operational advances of oceanographic observations by altimetry, including requirements for spatial and temporal resolution of altimetric measurements, their accuracy and continuity. There are also new challenges and new openings mentioned in the paper that are particularly crucial for observations at higher latitudes, for coastal oceanography, for cryospheric studies and for hydrology. The paper starts with a general introduction followed by a section on Earth System Science including Ocean Dynamics, Sea Level, the Coastal Ocean, Hydrology, the Cryosphere and Polar Oceans and the ‘‘Green” Ocean, extending the frontier from biogeochemistry to marine ecology. Applications are described in a subsequent section, which covers Operational Oceanography, Weather, Hurricane Wave and Wind Forecasting, Climate projection. Instruments’ development and satellite missions’ evolutions are described in a fourth section. A fifth section covers the key observations that altimeters provide and their potential complements, from other Earth observation measurements to in situ data. Section 6 identifies the data and methods and provides some accuracy and resolution requirements for the wet tropospheric correction, the orbit and other geodetic requirements, the Mean Sea Surface, Geoid and Mean Dynamic Topography, Calibration and Validation, data accuracy, data access and handling (including the DUACS system). Section 7 brings a transversal view on scales, integration, artificial intelligence, and capacity building (education and training). Section 8 reviews the programmatic issues followed by a conclusion

Altimetry for the future: building on 25 years of progress

In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and more recently, in 2018, in Ponta Delgada, Portugal, 25 Years of Progress in Radar Altimetry. On this latter occasion it was decided to collect contributions of scientists, engineers and managers involved in the worldwide altimetry community to depict the state of altimetry and propose recommendations for the altimetry of the future. This paper summarizes contributions and recommendations that were collected and provides guidance for future mission design, research activities, and sustainable operational radar altimetry data exploitation. Recommendations provided are fundamental for optimizing further scientific and operational advances of oceanographic observations by altimetry, including requirements for spatial and temporal resolution of altimetric measurements, their accuracy and continuity. There are also new challenges and new openings mentioned in the paper that are particularly crucial for observations at higher latitudes, for coastal oceanography, for cryospheric studies and for hydrology. The paper starts with a general introduction followed by a section on Earth System Science including Ocean Dynamics, Sea Level, the Coastal Ocean, Hydrology, the Cryosphere and Polar Oceans and the “Green” Ocean, extending the frontier from biogeochemistry to marine ecology. Applications are described in a subsequent section, which covers Operational Oceanography, Weather, Hurricane Wave and Wind Forecasting, Climate projection. Instruments’ development and satellite missions’ evolutions are described in a fourth section. A fifth section covers the key observations that altimeters provide and their potential complements, from other Earth observation measurements to in situ data. Section 6 identifies the data and methods and provides some accuracy and resolution requirements for the wet tropospheric correction, the orbit and other geodetic requirements, the Mean Sea Surface, Geoid and Mean Dynamic Topography, Calibration and Validation, data accuracy, data access and handling (including the DUACS system). Section 7 brings a transversal view on scales, integration, artificial intelligence, and capacity building (education and training). Section 8 reviews the programmatic issues followed by a conclusion

Denis Cailleaux. La cathédrale en chantier : la construction du transept de Saint-Etienne de Sens d'après les comptes de la fabrique, 1490-1517. Préface de Léon Pressouyre. Paris : Editions du Comité des travaux historiques et scientifiques, 1999. In-4°, 667 pages, ill. (Mémoires de la Section d'archéologie et d'histoire de l'art, 7.)

Hamon Etienne. Denis Cailleaux. La cathédrale en chantier : la construction du transept de Saint-Etienne de Sens d'après les comptes de la fabrique, 1490-1517. Préface de Léon Pressouyre. Paris : Editions du Comité des travaux historiques et scientifiques, 1999. In-4°, 667 pages, ill. (Mémoires de la Section d'archéologie et d'histoire de l'art, 7.). In: Bibliothèque de l'école des chartes. 2000, tome 158, livraison 2. pp. 614-618

Chantiers d’architecture à Bourges, XVe et XVIe siècle

Hamon Étienne. Chantiers d’architecture à Bourges, XVe et XVIe siècle. In: Bulletin Monumental, tome 167, n°4, année 2009. pp. 372-373

Chantiers d’architecture à Bourges, XVe et XVIe siècle

Hamon Étienne. Chantiers d’architecture à Bourges, XVe et XVIe siècle. In: Bulletin Monumental, tome 167, n°4, année 2009. pp. 372-373

Chantiers médiévaux, Paris-La Pierre-qui-Vire, 1996 (coll. Présence de l'art, vol. II).

Hamon Étienne. Chantiers médiévaux, Paris-La Pierre-qui-Vire, 1996 (coll. Présence de l'art, vol. II).. In: Bulletin Monumental, tome 155, n°2, année 1997. pp. 162-164

Fabienne Joubert, Le jubé de Bourges , Exposition-dossier du département des Sculptures, Musée du Louvre, Paris, Réunion des Musées Nationaux, 1994, 104 p.

Hamon Étienne. Fabienne Joubert, Le jubé de Bourges , Exposition-dossier du département des Sculptures, Musée du Louvre, Paris, Réunion des Musées Nationaux, 1994, 104 p.. In: Bulletin Monumental, tome 153, n°4, année 1995. pp. 396-397

Les débuts du chantier de l’Hôtel-Dieu de Bourges d’après les sources comptables (1508-1520)

Die Belegabschnitte der Rechnungsführung für den Bau des Hôtel-Dieu in Bourges liefert Angaben für die gesamte Bauzeit von 1508 bis 1527. Eine synthetische Zusammenstellung aller Daten in Form von Tabellen und Graphiken erweist die zeitliche Abfolge der einzelnen Bauabschnitte, identifiziert die jeweiligen Akteure und präzisiert bestimmte architektonische und technische Details. Andere Bereiche bleiben im Dunkel, etwa die Farbgestaltung imKellergeschoss. Die Identität des Architekten und die Herkunft des Bauleiters, Philippon Boulot, sowie seiner Partner werden durch die Rechnungsbücher anderer Baustellen erhellt. Wichtig ist insbesondere der Bau des Nordturms der Kathedrale von Bourges (1507-1535), der die Berufspraxis des Bauleiters und der Arbeiter am Hôtel-Dieu geprägt hat, diesem zugleich wertvolle Arbeitskräfte abzog, aber auch logistische und handwerkliche Unterstützung bot. Der Bau des Hôtel-Dieu bleibt sowohl finanziell wie vomEinsatz der Arbeitskräfte her weit hinter den großen Baustellen des Gothique flamboyant zurück, die zeitgleich oder kurz zuvor in Betrieb waren; deren Modellwirkung bot dem Hôtel-Dieu aber zugleich das Faustpfand für einen unstreitbaren architektonischen Erfolg.The vouchers preserved with the account books documenting the construction of the Hôtel-Dieu of Bourges cover the whole time of the building operations, from 1508 to 1527. A review of their contents in the formof tables and graphs makes it possible to ascertain the chronology, to describe the work of single individuals and to shed light on some technical aspects of the art of building. Nonetheless, the records remain unclear about other features, such as the use of colour on the basement. New evidence is also to be found in the account books of other building sites, concerning the author of the Bourges monument and the provenance of the foreman, Philippon Boulot, and of his assistants. The work which was then in progress on the north tower of Bourges cathedral (1507-1535) was of great consequence: it is there that both master and workmen acquired much of their craft; but it also detained the most talented among them; at the same time it provided logistical and technical support. The building of the Hôtel-Dieu thus appears as a subordinate project, as to funds and labour. Yet its very dependence on some of the major flamboyant projects of its time or of the recent past resulted in an indisputable architectural success.Étienne Hamon, Les débuts du chantier de l’Hôtel-Dieu de Bourges d’après les sources comptables (1508-1520), dans Bibliothèque de l’École des chartes, t. 161, 2003, p. 9-32. Les pièces justificatives des comptes du chantier de l’Hôtel-Dieu de Bourges couvrent toute la période de construction de l’édifice, de 1508 à 1527. La présentation synthétique de l’ensemble des données en tableaux et en graphiques permet de restituer la chronologie, de suivre les intervenants et de préciser certains aspects techniques de la construction. La documentation laisse subsister des zones d’ombre, sur la polychromie des soubassements notamment. L’identité du concepteur, l’origine du maître d’oeuvre, Philippon Boulot, et de ses associés s’éclairent à la consultation des comptabilités d’autres chantiers. Celui de la tour nord de la cathédrale de Bourges (1507-1535) a pesé d’un grand poids: étape majeure dans la formation du maître et des ouvriers de l’Hôtel-Dieu, il a aussi détourné les meilleurs talents, tout en fournissant un appui logistique et technique. La construction de l’Hôtel-Dieu apparaît ainsi comme une entreprise secondaire par son budget et ses moyens humains; mais sa dépendance à l’égard de grands chantiers flamboyants contemporains ou plus anciens a été le gage d’une incontestable réussite monumentale.Hamon Etienne. Les débuts du chantier de l’Hôtel-Dieu de Bourges d’après les sources comptables (1508-1520). In: Bibliothèque de l'école des chartes. 2003, tome 161, livraison 1. pp. 9-32

Ulrich Coenen, Die spätgotischen Werkmeisterbücher in Deutschland, Munich, Scaneg, 1990, 407 p.

Hamon Étienne. Ulrich Coenen, Die spätgotischen Werkmeisterbücher in Deutschland, Munich, Scaneg, 1990, 407 p.. In: Bulletin Monumental, tome 151, n°4, année 1993. p. 626