34.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 571 34.2 Latent Semantic Indexing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 572 34.3 Software Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

This talk is focused on such systems in overload. We look at a single queue and consider the scenario where customers leave impatient as their waiting time grows too large. We propose a fluid (functional LLN) approximation of this system and investigate the fixed point of this approximation. This leads to several qualitative insights into the dynamics of PS models with impatience. We show that ...

Conrad Hal Waddington?s ?Experiments on Embryonic Induction III,? published in 1934 in the Journal of Experimental Biology, describes the discovery that the primitive streak [7] induces the mammalian embryo. Waddington?s hypothesis was that a transplanted primitive streak [7] could induce neural tissue in the ectoderm [8] of the rabbit [9] embryo. The primitive streak [7] defines the axis of an...

We describe the cloning, expression pattern and functional overexpression analysis of Xotx5b, a new member of the Otx gene family in Xenopus laevis. Early expression of Xotx5b resembles that of Xotx2, being detected in the organizer region at early gastrula stage, and, shortly after, also in anterior neuroectoderm. During neurula stages Xotx5b exhibits a changing and dynamic pattern of expressi...

The most studied secondary neural organizer is the isthmic organizer, which is localized at the mid-hindbrain transition of the neural tube and controls the anterior hindbrain and midbrain regionalization. Otx2 and Gbx2 expressions are fundamental for positioning the organizer and the establishment of molecular interactions that induce Fgf8. We present here evidences demonstrating that Otx2 and...

Spemann's organizer has potent neural inducing and mesoderm dorsalizing activities in the Xenopus gastrula. A third activity, the organizer's ability to induce a secondary gut, has been difficult to analyze experimentally due to the lack of early gene markers. Here we introduce endodermin, a pan-endodermal gene marker, and use it to demonstrate that chordin (Chd), a protein secreted by the orga...

Virtual reality (VR) techniques offer us the ability to interact with computer images in a way never before experienced. The computer, and later computer graphics, revolutionized the way in which engineers design and manufacture products, and now virtual reality holds the potential to further revolutionize the engineering design cycle by providing engineers with a new window into the computer w...

The foundation for the anatomical and functional complexity of the vertebrate central nervous system is laid during embryogenesis. After Spemann's organizer and its derivatives have endowed the neural plate with a coarse pattern along its anteroposterior and mediolateral axes, this basis is progressively refined by the activity of secondary organizers within the neuroepithelium that function by...