Abstract: The disclosure provides a biological brain-computer interface comprising genetically modified cells engrafted onto an adult mammal (e.g., mouse) above cortical layer 1, forming an artificial cortical layer termed layer zero (L0). Following engraftment, L0 goes through a developmental process characterized by synchronous waves of activity that gradually recede to resemble spontaneous cortical activity. Axons and dendrites from L0 nondestructively infiltrated the host cortex and formed synaptic connections necessary for bidirectional communication with the brain.

Abstract: Methods and systems of using a laser beam to weld an object with a non-flat surface, including curved surfaces, are described, where at least one piece of the object is transparent. An optical guide with a flat surface and an interface surface is placed on a piece of an object to welded. The interface surface is fabricated to form-fit the non-flat surface of the object to be welded, and is opposite the flat surface. A liquid optical medium is applied between the non-flat surface and the interface surface, filling any gaps or surface defects. The laser beam is then transmitted through the optical guide, liquid optical medium, and into the object to be welded, to a location to be welded. The laser beam then welds the object to be welded at pre-determined points.