AARON is a program designed to investigate the cognitive principles underlying visual representation. Under continuous development for fifteen years, it is now able autonomously to make "freehand" drawings of people in garden-like settings. This has required a complex interplay between two bodies of knowledge: objectspecific knowledge of how people are constructed and how they move, together wi...

a 25 year-old construction worker underwent neck laceration following penetrating neck trauma in a falling incident. the 3rd tracheal ring was injured which was initially repaired and the patient was discharged in good general condition. (figure 1 shows the patient’s neck view after discharge from hospital).two months later the patient was again admitted due to provocative coughing and a metal ...

2 SI A. Y. Tulchinsky et al.

Let n be an integer and q be a prime power. Then for any 3 ≤ n ≤ q − 1, or n = 2 and q odd, we construct a connected q-regular edgebut not vertextransitive graph of order 2qn+1. This graph is defined via a system of equations over the finite field of q elements. For n = 2 and q = 3, our graph is isomorphic to the Gray graph.

In this paper we study finite, connected, 4-valent graphs X which admit an action of a group G which is transitive on vertices and edges, but not transitive on the arcs of X. Such a graph X is said to be (G, 1 2)-transitive. The group G induces an orientation of the edges of X, and a certain class of cycles of X (called alternating cycles) determined by the group G is identified as having an im...