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International audience; In this paper, we introduce the development of a bio-inspired system that mimics the angular acceleration sensor function provided by the vestibular system. The prototype is made of a Plexiglas piece that presents the pattern of a semicircular canal at scale 10, with a simplified geometry. A flexible piezoresistive cantilever integrated on polyimide substrate is used to model the electro-mechanical transduction of the cupula/hair cells system. The electro-mechanical response of the complete system is analyzed when submitted to both pulse and sine rotational excitations. It is demonstrated that the biomimetic system only responds to one rotational axis, and is also sensitive to the rotational direction. We also validate that the prototype actually responds to the expected medium vestibular frequencies (from 0.16Hz to 0.64Hz).

We introduce a nonlinear all-optical theranostics protocol based on the excitation wavelength decoupling between imaging and photoinduced damage of human cancer cells labeled by bismuth ferrite (BFO) harmonic nanoparticles (HNPs). To characterize the damage process, we rely on a scheme for in situ temperature monitoring based on upconversion nanoparticles: by spectrally resolving the emission of silica coated NaGdF4:Yb3+/Er3+ nanoparticles in close vicinity of a BFO HNP, we show that the photointeraction upon NIR-I excitation at high irradiance is associated with a temperature increase >100 °C. The observed laser–cell interaction implies a permanent change of the BFO nonlinear optical properties, which can be used as a proxy to read out the outcome of a theranostics procedure combining imaging at 980 nm and selective cell damage at 830 nm. The approach has potential applications to monitor and treat lesions within NIR light penetration depth in tissues.