Un monastère et son patron

De tout temps, et de nos jours encore, tout monastère a son saint patron. Mais actuellement on parlera plutôt de titulaire et ce titulaire pourra au besoin être changé, sans que cela ne pose de problème. Ainsi, une communauté de moniales qui s’est récemment transférée d’un lieu à un autre a trouvé tout à fait normal de changer de patronage à cette occasion. Au Moyen Âge, il n’en était pas ainsi, mais, comme l’a magistralement montré Peter Brown, le saint patron : « avait pris tous les traits ..

The Relative Roles of Passive Surface Forces and Active Ion Transport in the Modulation of Airway Surface Liquid Volume and Composition

Two hypotheses have been proposed recently that offer different views on the role of airway surface liquid (ASL) in lung defense. The “compositional” hypothesis predicts that ASL [NaCl] is kept low (<50 mM) by passive forces to permit antimicrobial factors to act as a chemical defense. The “volume” hypothesis predicts that ASL volume (height) is regulated isotonically by active ion transport to maintain efficient mechanical mucus clearance as the primary form of lung defense. To compare these hypotheses, we searched for roles for: (1) passive forces (surface tension, ciliary tip capillarity, Donnan, and nonionic osmolytes) in the regulation of ASL composition; and (2) active ion transport in ASL volume regulation. In primary human tracheobronchial cultures, we found no evidence that a low [NaCl] ASL could be produced by passive forces, or that nonionic osmolytes contributed substantially to ASL osmolality. Instead, we found that active ion transport regulated ASL volume (height), and that feedback existed between the ASL and airway epithelia to govern the rate of ion transport and volume absorption. The mucus layer acted as a “reservoir” to buffer periciliary liquid layer height (7 μm) at a level optimal for mucus transport by donating or accepting liquid to or from the periciliary liquid layer, respectively. These data favor the active ion transport/volume model hypothesis to describe ASL physiology

Software Architectures and Multiple Variability

International audienceDuring the construction of software product lines, variability management is a crucial activity. A large number of software variants must be produced, in most cases, by using extensible architectures. In this chapter, we present the various applications of a set of modular management variability tools (FAMILIAR) for different forms of architecture (component-, service- and plug-in-based), and at different stages of the software life cycle. We discuss the lessons learnt from these studies and present guidelines for resolving recurring problems linked to multiple variability and to software architecture