Neuronal plasticity of the inner retina has been observed in response to photoreceptor degeneration. Typically, this phenomenon has been considered maladaptive and may preclude vision restoration in the blind. However, several recent studies utilizing triggered photoreceptor ablation have shown adaptive responses in bipolar cells expected to support normal vision. Whether such homeostatic plasticity occurs during progressive photoreceptor degenerative disease to help maintain normal visual behavior is unknown. We addressed this issue in an established mouse model of Retinitis Pigmentosa caused by the P23H mutation in rhodopsin. We show robust modulation of the retinal transcriptomic network, reminiscent of the neurodevelopmental state, and potentiation of rod – rod bipolar cell signaling following rod photoreceptor degeneration. Additionally, we found highly sensitive night vision in P23H mice even when more than half of the rod photoreceptors were lost. These results suggest retinal adaptation leading to persistent visual function during photoreceptor degenerative disease.

We show how spatial dispersion can be used as a mechanism to customize the longitudinal profiles of electric fields inside modulated wire media, using a fast and remarkably accurate 1D inhomogeneous model. This customization gives fine control of the sub-wavelength behaviour of the field, as has been achieved recently for transverse fields in simpler slotted-slab media. Our scheme avoids any necessity to run a long series of computationally intensive 3D simulations of specific structures, in order to iteratively converge (or brute-force search) to an empirical 'best-performance' design according to an abstract figure-of-merit. Instead, if supplied with an 'ideal waveform' profile, we could now calculate how to construct it directly. Notably, and unlike most work on photonic crystal structures, our focus is specifically on the field profiles because of their potential utility, rather than other issues such as band-gap control, and/or transmission and reflection coefficients.

Electromagnetic mode profile shaping would be a very useful technique, with applications including in accelerator science and data transmission. Two methods are proposed: one varying the permittivity and the other using a wire medium. By the use of Mathieu functions, we demonstrate a flatter, a triangular and a peakier profile. The first two may be used to manipulate longer particle bunches, while the last could be used on shorter bunches and in data transmission. It is also demonstrated how further improvements can be achieved by going beyond Mathieu functions.