Temperature, light and nitrate sensing coordinate Arabidopsis seed dormancy cycling resulting in winter and summer annual phenotypes

Seeds use environmental cues to sense the seasons and their surroundings to initiate the plants life cycle. Dormancy cycling underlying this process is extensively described, but the molecular mechanism is largely unknown. To address this we selected a range of representative genes from published array experiments in the laboratory and investigated their expression patterns in seeds of Arabidopsis ecotypes, having contrasting life cycles, over an annual dormancy cycle in the field. We show how mechanisms identified in the laboratory are coordinated in response to the soil environment to determine dormancy cycles that result in winter and summer annual phenotypes. Our results are consistent with a seed specific response to seasonal temperature patterns (temporal sensing) involving the gene DELAY OF GERMINATION1 (DOG1) that indicates the correct season; and concurrent temporally driven co-opted mechanisms that sense spatial signals i.e. nitrate via CBL-INTERACTING PROTEIN KINASE 23 (CIPK23) phosphorylation of the NITRATE TRANSPORTER 1 (NRT1.1) and light via PHYTOCHROME A (PHYA). In both ecotypes studied, when all three genes have low expression there is enhanced GIBBERELLIN 3 BETA-HYDROXYLASE 1 (GA3ox1) expression, exhumed seeds have the potential to germinate in the laboratory, and the initiation of seedling emergence occurs following soil disturbance (exposure to light) in the field. Unlike DOG1, expression of MOTHER of FLOWERING TIME (MFT) has an opposite thermal response in seeds of the two ecotypes indicating a role in determining their different dormancy cycling phenotypes

Emergent situations in interactive storytelling

Interactive storytelling can either be based on explicit plot representations or on the autonomous behaviour of artificial characters. In such a character-based approach, the dynamic interaction between characters generates the actual plot from a generic storyline. Characters' behaviours are implemented through real-time search-based planning techniques. However, the top-down planning systems that control artificial actors need to be complemented with appropriate mechanisms dealing with emerging ("bottom-up") situations of narrative relevance. After discussing the determinants of plot variability and the mechanisms that account for the emergence of narrative situations, we introduce additional mechanisms for coping with these situations. Thes

Developing Re-Usable Interactive Storytelling Technologies

Abstract: Despite the growing interest in Interactive Storytelling (IS), there have been only a small number of implemented demonstrators and few have attempted at developing a re-usable IS technology. In this paper we describe such an IS engine, which is the result of several years of experimentation in the field. The system is based on a game engine for its visualisation component, while the narrative generation component implements a variant of HTN Planning. After an introduction to the principles underlying the system, we introduce the associated production process and discuss authoring problems as well as tools we have developed to facilitate the use of the technology

Sex, lies, and video games::An interactive storytelling prototype

The authors describe a first prototype of an Interactive Storytelling system, whose objective is to allow user intervention within a pre-defined storyline. The system is character-based rather than plot-based, each character’s role being dynamically computed using HTN planning. The interaction between characters creates various instantiations of the baseline narrative, with which the user can interfere at any time. After introducing the basic AI techniques used in the prototype, the authors discuss the modalities of user intervention and present an example story produced by the system

Non-instructional linguistic communication with virtual actors

In this paper, we explore a new paradigm for natural language communication with autonomous agents. While the dominant paradigm is to use natural language instructions from which the agent behaviour is generated, we investigate how natural language input can influence a pre-existing planbased behaviour, by interfering with the various types of sub-goals in such a plan. Using as a testbed a fully-implemented interactive storytelling application based on virtual actors, we identify various forms of communicative actions and how these can influence actors' behaviours. We report early results from the use of a speech processing system, used within the storytelling application to influence the behaviour of the artificial actors

Character-Based Interactive Storytelling

is a privileged application of intelligent virtual-actors technology. The authors introduce their character-based interactive storytelling prototype that uses Hierarchical Task Network planning techniques, which support story generation and anytime user intervention

Planning formalisms and authoring in interactive storytelling

Interacting Storytelling systems integrate AI techniques such as planning with narrative representations to generate stories. In this paper, we discuss the use of planning formalisms in Interactive Storytelling from the perspective of story generation and authoring. We compare two different planning formalisms, Hierarchical Task Network (HTN) planning and Heuristic Search Planning (HSP). While HTN provide a strong basis for narrative coherence in the context of interactivity, HSP offer additional flexibility and the generation of stories and the mechanisms for generating comic situations

Multimodal acting in mixed reality interactive storytelling

An experimental mixed reality using a multimodal approach lets users play characters in interactive narratives as though acting on a stage. Users interact with characters through speech, attitude, and gesture, enhancing their immersion in the virtual world