7,667 research outputs found
Coarse-grained Description of Polymer Blends as Interacting Soft-Colloidal Particles
We present a theoretical approach which maps polymer blends onto mixtures of
soft-colloidal particles. The analytical mesoscale pair distribution functions
reproduce well data from united atom molecular dynamics simulations of
polyolefin mixtures without fitting parameters. The theory exactly recovers the
analytical expressions for density and concentration fluctuation structure
factors of soft colloidal mixtures (liquid alloys).Comment: 27 REVTex4 pages, 8 PostScript figures, 1 table accepted for
publication in Journal of Chemical Physic
Cherenkov Telescope Array: The next-generation ground-based gamma-ray observatory
High energy gamma-ray astronomy is a newly emerging and very successful
branch of astronomy and astrophysics. Exciting results have been obtained by
the current generation Cherenkov telescope systems such as H.E.S.S., MAGIC,
VERITAS and CANGAROO. The H.E.S.S. survey of the galactic plane has revealed a
large number of sources and addresses issues such as the question about the
origin of cosmic rays. The detection of very high energy emission from
extragalactic sources at large distances has provided insights in the star
formation during the history of the universe and in the understanding of active
galactic nuclei. The development of the very large Cherenkov telescope array
system (CTA) with a sensitivity about an order of magnitude better than current
instruments and significantly improved sensitivity is under intense discussion.
This observatory will reveal an order of magnitude more sources and due to its
higher sensitivity and angular resolution it will be able to detect new classes
of objects and phenomena that have not been visible until now. A combination of
different telescope types will provide the sensitivity needed in different
energy ranges.Comment: 4 pages, 3 figures, to appear in the proceedings of the 30th
International Cosmic Ray Conference, Merida, July 200
Étude des caractères non-métriques dans une population d'ours des cavernes (Ursus spelaeus ROSENMÜLLER & HEINROTH, 1794) provenant de la grotte de Vaucluse (Doubs, France)
Many bones of cave bear were found in the cave of Vaucluse (Doubs, France). The JAGHER\u27S collection is part of this material and was the subject of my thesis, supervised by Professor Louis CHAIX. This study presents information on several non-metric features -such as the number of premolars, the supra-trochlear foramen, the folds of the os carpi ulnare, the sagittal sulcus, the astragaliaulcus, the congenital absence of a tooth or the fusion of two bones - as observed in the population of cave bears from the cave of Vaucluse. Most of these non-metric features have previously been described for other populations, providing a basis for comparison. Their frequency differs between populations, suggesting that they can provide evidence of population biology
Cave of La Chěnelaz (Hostias, Ain, France). The large Mammals of the layer 6b
More than 3600 remains of large Mammals have been discovered in layer 6b of the cave of La Chenelaz, about 33\u27000 years ago. The identified taxa belong to the orders of Insectivora, Carnivora, Lagomorpha, Rodentia, Perissodactyla and Artiodactyla. The Carnivora are the most numerous with 38% of the remains. At this time, the cave was occupied by bears (cave bears mainly and brown bears) which hibernated there. Alternatively, it was a lair for hyaenas and wolves, who raised their cubs there and brought their preys (Perissodactyla and Artiodactyla mainly), and smaller Carnivora like the red fox or the pine marten. Many of the studied species indicate a warm and woody climate. Some remains belong to the porcupine. The genus Hystrix is present in Europe during the Pleistocene but is always scarce. No trace of human occupation was discovered in layer 6b
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