From the body to the tools and back: A general framework for presence in mediated interactions

Different neuropsychological studies clearly show that the perception of our body and its surrounding space is not a given fact but it is influenced by the outcome of our actions (both direct and mediated by the use of tools). In this view, a possible starting point for a better understanding of Presence in computer-mediated interactions is the study of mediated action and its effects on our spatial experience.Following a cognitive perspective, the presented framework describes Presence as an intuitive feeling which is the outcome of an experience-based metacognitive judgment that controls our action. This process monitors pre-reflexively our activity by using an embodied intuitive simulation of the intended action developed through practice (implicit learning).When actions are implemented using one or more tools, it is possible to distinguish between two different types of mediated action: first-order (I use the body to control a proximal artifact, e.g. a tennis player striking the ball with the racquet) or second-order (I use the body to control a proximal artifact that controls a different distal one, e.g. a cranemen using a lever to move a mechanical boom to lift materials). These two mediated actions, when produced intuitively, have different effects on our experience of body and space: a successfully learned first-order mediated action produces incorporation – the proximal tool extends the peripersonal space of the subject – while a successfully learned second-order mediated action produces also incarnation – a second peripersonal space centered on the distal tool.     

Nanostructured Superhydrophobic Substrates Trigger the Development of 3D Neuronal Networks

The generation of 3D networks of primary neurons is a big challenge in neuroscience. Here, a novel method is presented for a 3D neuronal culture on superhydrophobic (SH) substrates. How nano‐patterned SH devices stimulate neurons to build 3D networks is investigated. Scanning electron microscopy and confocal imaging show that soon after plating neurites adhere to the nanopatterned pillar sidewalls and they are subsequently pulled between pillars in a suspended position. These neurons display an enhanced survival rate compared to standard cultures and develop mature networks with physiological excitability. These findings underline the importance of using nanostructured SH surfaces for directing 3D neuronal growth, as well as for the design of biomaterials for neuronal regeneration.     

Carbon-rich SiCN ceramics derived from phenyl-containing poly(silylcarbodiimides)

Novel phenyl-containing polysilylcarbodiimides were synthesized and their thermolysis and crystallization behavior up to 2000 °C was investigated. The Si/C ratio of the preceramic polymer was varied in a defined way by starting from dichlorosilanes with different organic substituents, namely R and R′ with R = phenyl and R′ = H, phenyl, methyl or vinyl. Several techniques were employed to study the structural features of the polymers and their thermolysis products. The temperature of crystallization depends on the carbon content of the precursors. Thus, in the sample with the highest carbon content the separation of β-SiC from the amorphous SiCN matrix is observed at T > 1500 °C, resulting in the highest temperature of thermal stability against crystallization ever reported for a SiCN ceramic derived from polysilylcarbodiimides. Moreover, no crystallization of β-Si₃N₄ was observed.