Entorhinal-retrosplenial circuits for allocentric-egocentric transformation of boundary coding

Spatial navigation requires landmark coding from two perspectives, relying on viewpoint-invariant and self-referenced representations. The brain encodes information within each reference frame but their interactions and functional dependency remains unclear. Here we investigate the relationship between neurons in the rat's retrosplenial cortex (RSC) and entorhinal cortex (MEC) that increase firing near boundaries of space. Border cells in RSC specifically encode walls, but not objects, and are sensitive to the animal’s direction to nearby borders. These egocentric representations are generated independent of visual or whisker sensation but are affected by inputs from MEC that contains allocentric spatial cells. Pharmaco- and optogenetic inhibition of MEC led to a disruption of border coding in RSC, but not vice versa, indicating allocentric-to-egocentric transformation. Finally, RSC border cells fire prospective to the animal’s next motion, unlike those in MEC, revealing the MEC-RSC pathway as an extended border coding circuit that implements coordinate transformation to guide navigation behavior.

System Design of Numerical Control Turret Press Based on Motion Controller

According to the characteristics and requirements of NCT processing system, deeper research was done on the system. The three-module design has been completed based on motion controller. The first module is completed on the design of panel, key position, machine functions and coding circuit; the second module is mainly accomplished on the tool-path generation, tool adapter and program development; the last module is used to verify the NC codes. Thus the NCT processing system is improved effectively.

Design and Realization of Color Character Overlay Based on AT89S51 and MC1377

This paper describes a color character overlay using color synchrolock and coding circuit composed of color television integrated circuit AT89S51and MC1377, introduces the basic method of overlay color character on television image, discusses relevant theory from microcomputer video image and color character overlay, puts forward a new character overlay method, and gives the video image character overlay’s design method based on AT89S51.