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Commissural axon guidance requires complex modulations of growth cone sensitivity to midline-derived cues, but underlying mechanisms in vertebrates remain largely unknown. By using combinations of ex vivo and in vivo approaches, we uncovered a molecular pathway controlling the gain of response to a midline repellent, Semaphorin3B (Sema3B). First, we provide(More)
Simultaneous recording from 21 electrode sites in a 4 X 4 mm area over the posterior cortex was used to determine the surface distribution of all major peaks which constitute flash-evoked potentials (FEPs) and pattern reversal evoked-potentials (PREPs) in hooded rats. Topographical maps were constructed with respect to Bregma and midline reference points.(More)
— This paper presents a distributed particle filter al­ gorithm for localizing multiple mobile robots that are equipped only with low cost/low power sensors. This method is applicable to multi-micro robot systems, where size limitations restrict sensor selection (e.g. small infrared range finders). Localization of three robots in a known environment is(More)
— Inverse kinematics is a nonlinear problem that may have multiple solutions. A Genetic Algorithm(GA) for solving the inverse kinematics of a serial robotic manipulator is presented. The algorithm is capable of finding multiple solutions of the inverse kinematics through niching methods. Despite the fact that the number and position of solutions in the(More)
—A 64 2 64 element CMOS active pixel sensor (APS) for star tracker applications is reported. The chip features an innovative regional electronic shutter through the use of an individual pixel reset architecture. Using the regional electronic shutter, each star in the field of view can have its own integration period. This way, simultaneous capture of bright(More)
In this paper we describe our early exploration of automatic recognition of conversational speech in meetings for use in automatic summarizers and browsers to produce meeting minutes effectively and rapidly. To achieve optimal performance we started from two different baseline English rec-ognizers adapted to meeting conditions and tested resulting(More)
The ocular motor system consists of three nerves which innervate six muscles to control eye movements. In humans, defective development of this system leads to eye movement disorders, such as Duane Retraction Syndrome, which can result from mutations in the α2-chimaerin signaling molecule. We have used the zebrafish to model the role of α2-chimaerin during(More)
This paper addresses the challenging problem of finding collision-free trajectories for many robots moving to individual goals within a common environment. Most popular algorithms for multi-robot planning manage the complexity of the problem by planning trajectories for robots sequentially; such decoupled methods may fail to find a solution even if one(More)
Design considerations and description of a CMOS Active Pixel image sensor (APS) star tracker are reported. APS technology has been thought of being most appropriate for guidance and navigation. However, making APS useful for future star tracker missions means a few challenges have to be overcome. A wider dynamic range is required, while fill factor ought to(More)
Eye movements depend on correct patterns of connectivity between cranial motor axons and the extraocular muscles. Despite the clinical importance of the ocular motor system, little is known of the molecular mechanisms underlying its development. We have recently shown that mutations in the Chimaerin-1 gene encoding the signaling protein α2-chimaerin(More)