An increasing number of our interactions are mediated through e-technologies. In order to enhance the human's feeling of presence into these virtual environments, also known as telepresence, the individual is usually embodied into an avatar. The natural adaptation capabilities, underlain by the plasticity of the body schema, of the human being make a body ownership of the avatar possible, in which the user feels more like his/her virtual alter ego than himself/herself. However, this phenomenon only occurs under specific conditions. Two experiments are designed to study the human's feeling and performance according to a scale of natural relationship between the participant and the avatar. In both experiments, the human-avatar interaction is carried out by a Natural User Interface (NUI) and the individual's performance is assessed through a behavioural index, based on the concept of affordances, and a questionnaire of presence The first experiment shows that the feeling of telepresence and ownership seem to be greater when the avatar's kinematics and proportions are close to those of the user. However, the efficiency to complete the task is higher for a more mechanical and stereotypical avatar. The second experiment shows that the manipulation of the viewpoint induces a similar difference across the sessions. Results are discussed in terms of the neurobehavioral processes underlying performance in virtual worlds, which seem to be based on ownership when the virtual artefact ensures a preservation of sensorimotor contingencies, and simple geometrical mapping when the conditions become more artificial.

Mannosylerythritol lipids (MELs) are biosurfactants with excellent biochemical properties and a wide range of potential applications. However, most of the studies focusing on MELs high titre production have been relying in the use of vegetable oils with impact on the sustainability and process economy. Herein, we report for the first time MELs production using oils produced from microalgae. The bio-oil was extracted from Neochloris oleoabundans and evaluated for their use as sole carbon source or in a co-substrate strategy, using as an additional carbon source D-glucose, on Moesziomyces spp. cultures to support cell growth and induce the production of MELs. Both Moesziomyces antarcticus and M. aphidis were able to grow and produce MELs using algae-derived bio-oils as a carbon source. Using a medium containing as carbon sources 40 g/L of D-glucose and 20 g/L of bio-oils, Moesziomyces antarcticus and M. aphidis produced 12.47 ± 0.28 and 5.72 ± 2.32 g/L of MELs, respectively. Interestingly, there are no significant differences in productivity when using oils from microalgae or vegetable oils as carbon sources. The MELs productivities achieved were 1.78 ± 0.04 and 1.99 ± 0.12 g/L/h, respectively, for M. antarcticus fed with algae-derived or vegetable oils. These results open new perspectives for the production of MELs in systems combining different microorganisms.

Part 1: Fundamental IssuesInternational audienceVirtual environments are an increasing trend in today’s society. In this scope, the avatar is the representation of the user in the virtual world. However, that relationship lacks empirical studies regarding the nature of the interaction between avatars and human beings. For that purpose it was studied how the avatar’s modeled morphology and dynamics affect its control by the user. An experiment was conducted to measure telepresence and ownership on participants who used a Kinect Natural User Interface (NUI). The body ownership of different avatars was assessed through a behavioral parameter, based on the concept of affordances, and a questionnaire of presence. The results show that the feelings of telepresence and ownership seem to be greater when the kinematics and the avatar’s proportions are closer to those of the user