We construct cocycles on the Lie algebra of pseudo- and q-pseudodifferential symbols of one variable and on their close relatives: the sine-algebra and the Poisson algebra on two-torus. A ``quantum'' Godbillon-Vey cocycle on (pseudo)-differential operators appears in this construction as a natural generalization of the Gelfand-Fuchs 3-cocycle on

Recent isotopic and mineralogical studies have demonstrated a temporal and chemical link between the Chicxulub multiring impact basin and ejecta at the Cretaceous-Tertiary boundary. A fundamental problem yet to be resolved, however, is identification of the projectile responsible for this cataclysmic event. Drill core samples of impact melt rock

We discuss narrow band CCD imaging of NGC 4861 in continua at 4500 A, 5300 A and 6300 A as well as in Hα, Hβ and (O III] λ5007 A lines. We find that the system exhibits a double nucleus structure and a counter-tail to the well-known northeast chain of HII regions. The mean value of lines and continua frames for the main body brightness distribution

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The region around the Herbig Ae/Be star LKH-alpha198 was imaged at 10 micrometer with the CAMIRAS camera at the Canada-France-Hawaii Telescope and the Nordic Optical Telescope. We discovered a deeply embedded companion 6 sec north of LKH-alpha198, which may be responsible for most of the far-infrared emission in the region and for driving the