A Silurian shift in fluvial stratigraphic architecture, coincident with the appearance of terrestrial vegetation fossil record, is traditionally cited as evidence for exclusively shallow, braided planforms pre-vegetation rivers. While recent recognition deep, single-thread channels pre-Silurian strata challenge this paradigm, it unclear how these rivers maintained stable banks. Here, we reconst...

Vice Chairmen Mr. and Mrs. W. Dillaway Ayres, Jr. Dr. Joanne Berger-Sweeney Mr. and Mrs. Hans E.R. Bosch Mr. and Mrs. Matthew J. Bruderman Mr. and Mrs. Eric Carlstrom Mr. and Mrs. James J. Celestino Mr. and Mrs. Edward A. Chernoff Mr. and Mrs. Charles “Casey” Cogut Mr. and Mrs. Michel David-Weill Ms. Florence A. Davis Mr. and Mrs. Nelson DeMille Mr. and Mrs. John M. Desmarais Mr. Martin Elias M...

Many syndromes are named in an eponymous fashion after the original authors, or occasionally after the original patients, but the name of this syndrome is derived from the hospitals where the first two patients were described. In 1973 Pelletier and Feingold' described a boy seen at the Boston Floating Hospital with short stature, delayed speech development, and a striking facial appearance. A f...

In this thesis we address the problem of drift-free navigation for underwater vehicles performing harbor surveillance and ship hull inspection. Maintaining accurate localization for the duration of a mission is important for a variety of tasks, such as planning the vehicle trajectory and ensuring coverage of the area to be inspected. Our approach uses only onboard sensors in a simultaneous loca...

process of gastrulation in a whole series of different ways — for example, as a sequence of drawings taken from the classic work on the subject by Nieuwkoop and Faber, which have been 'morphed' together into a movie. There is also a movie showing the external movements of gastrulation recorded using a conventional light microscope, and also a movie showing the internal movements of gastrulation...

In a model for rotating non-Boussinesq convection with mean flow we identify a regime of spatiotemporal chaos that is based on a hexagonal planform and is sustained by the induced nucleation of dislocations by penta-hepta defects. The probability distribution function for the number of defects deviates substantially from the usually observed Poisson-type distribution. It implies strong correlat...