During volcanic eruptions, aviation stakeholders require an assessment of the volcanic ash hazard. Operators and regulators are required to make fast decisions based on deterministic forecasts, which are subject to various sources of uncertainty. For a robust decision to be made, a measure of the uncertainty of the hazard should be considered, but this can lead to added complexity preventing fast decision-making. A proof-of-concept risk-matrix approach is presented that combines uncertainty estimation and volcanic ash hazard forecasting into a simple warning system for aviation. To demonstrate the methodology, an ensemble of 600 dispersion model simulations is used to characterize uncertainty (due to eruption source parameters, meteorology and internal model parameters) in ash dosages and concentrations for a hypothetical Icelandic eruption. To simulate aircraft encounters with volcanic ash, trans-Atlantic air routes between New York (JFK) and London (LHR) are generated using time-optimal routing software. This approach was developed in collaboration with operators, regulators and engine manufacturers; it demonstrates how an assessment of ash dosage and concentration risk can be used to make fast and robust flight-planning decisions, even when the model uncertainty spans several orders of magnitude. The results highlight the benefit of using an ensemble over a deterministic forecast and a new method for visualizing dosage risk along flight paths. The risk-matrix approach is applicable to other aviation hazards such as sulphur dioxide (SO 2 ) dosages, desert dust, aircraft icing and clear-air turbulence, and is expected to aid flight-planning decisions by improving the communication of ensemble-based forecasts to aviation.

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The theoretical aim of this article is to integrate the singulative into the theory of division proposed by Borer (2005) and other theoretical linguists (e.g., Krifka 1995 , Doetjes 1996 , 1997 , Chierchia 1998 , Cheng and Sybesma 1999 ). To illustrate my claim, I offer a brief case study of Ojibwe, an Algonquian language, which I argue uses gender shift (from inanimate to animate) to mark singulativization. Singulatives, as morphological markers, are primarily known from Celtic, Afro-Asiatic, and Nilo-Saharan languages, but are not a known feature of Algonquian languages. Further support for my claim that the grammar of Algonquian languages embeds a singulative system comes from Fox (Mesquakie).

The aim of this paper is two-fold: on the one hand, its purpose is to show that Stylistic Fronting was very productive in Old French; on the other, its rationale is the introduction of a novel hypothesis according to which Stylistically Fronted elements in Old French target a special Topic phrase. This phrase is labelled TopicP+ to distinguish it from TopicP, the position where topicalized elements in V2 structures raise to in Old French. The special topic position accessed by Stylistic Fronting is motivated by the main pattern emerging from a series of carefully studied Old French texts: two elements can undergo SF at the same time, but the two elements cannot both be XPs or both be heads. It is further demonstrated that the subject gap constraint that accompanies Stylistic Fronting in Modern Insular Scandinavian languages is also relevant for Old French and that the most natural way to account for it is to suppose that Stylistically Fronted XPs move through (rather than into, cf. Holmberg 2000) the specifier of Spec-TP. This is made to follow from the fact that TP in Old French is a (strong) phase. The account relies on the splitting of the EPP between two features, [P] and [D], and on the idea that these features may not necessarily come packaged as a bundle. [P] can appear on one head while [D] surfaces on another, with [P] depending on [D]. In the second part of the paper, an explanation is given as to why Stylistic Fronting disappeared from French grammar: the hypothesis put forward is that once verbal agreement lost its pronominal

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