Plesippus francescana (Frick) from the late Pliocene, Coso Mountains, California, with a review of the genus Plesippus

Two mammalian types, occurring in a late Pliocene fauna from the Coso Mountains, California, have already been described. Among the more abundant forms in this assemblage are the horses of the genus Plesippus. These are of particular interest not only for purposes of correlation of the geologic horizon in which they occur, but also because of their phylogenetic relationships. Opportunity is taken therefore to make a comparative study of characters of the species from the Coso Mountains with reference to nearly related forms found in beds of similar age and to define more clearly, than has been previously attempted, the position of Plesippus in the lineage of the horse group

Tilted phase space measurements

We show that the phase shift of {\pi}/2 is crucial for the phase space translation covariance of the measured high-amplitude limit observable in eight-port homodyne detection. However, for an arbitrary phase shift {\theta} we construct explicitly a different nonequivalent projective representation of R$^2$ such that the observable is covariant with respect to this representation. As a result we are able to determine the measured observable for an arbitrary parameter field and phase shift. Geometrically the change in the phase shift corresponds to the tilting of one axis in the phase space of the system.Comment: 4 pages, 4 figure

Cryogenic Mechanical Alloying of Poly (ether ether ketone) - Polycarbonate Composite Powders for Selective Laser Sintering

Mechanical alloying is a solid state processing technique traditionally used in the metallurgical industry to extend solubility limits in alloy systems. Mechanical alloying can also be used to blend polymer systems at ambient or cryogenic temperatures. In this work, cryogenic mechanical alloying was employed to create composite powders of Poly (ether ether ketone) (PEEK) - Polycarbonate (PC) for use in selective laser sintering applications. The microstructural development of the PEEK-PC system that occurs during laser sintering and the effects of this microstructure on mechanical properties of the laser sintered parts was investigated.Mechanical Engineerin

Investigation of potential anti-radiation and anti-neoplastic compounds related to plant growth regulators second quarterly progress report, 1 oct. 1964 - 1 jan. 1965

Antiradiation and antineoplastic compounds related to plant growth regulators - cytotoxic effects and radiation protectio

Timing of ancient extensional tectonic features on Mars

Although numerous studies have delineated the Tharsis and post-Tharsis volcanic/tectonic history on Mars, only a few attempts have examined the earlier epochs. This is not an easy task since unambiguous crater ages for pre-Tharsis and early Tharsis units are difficult to determine owing to a variety of active surface processes. Ancient tectonic features, however, have a sufficiently large superposed crater population that should permit relative dating. A technique for crater counting along linear features analagous to areal crater density is proposed. A modification of this approach has been tested and applied to a variety of ancient tectonic features

Floor-fractured crater models of the Sudbury structure, Canada

The Sudbury structure in Ontario, Canada, is one of the oldest and largest impact structures recognized in the geological record. It is also one of the most extensively deformed and volcanically modified impact structures on Earth. Although few other terrestrial craters are recognized as volcanically modified, numerous impact craters on the Moon have been volcanically and tectonically modified and provide possible analogs for the observed pattern of modification at Sudbury. We correlate the pattern of early deformation at Sudbury to fracture patterns in two alternative lunar analogs and then use these analogs both to estimate the initial size of the Sudbury structure and to model the nature of early crater modification at Sudbury