2,107 research outputs found
Sequestration of noble gases in giant planet interiors
The Galileo probe showed that Jupiter's atmosphere is severely depleted in
neon compared to protosolar values. We show, via ab initio simulations of the
partitioning of neon between hydrogen and helium phases, that the observed
depletion can be explained by the sequestration of neon into helium-rich
droplets within the postulated hydrogen-helium immiscibility layer of the
planet's interior. We also demonstrate that this mechanism will not affect
argon, explaining the observed lack of depletion of this gas. This provides
strong indirect evidence for hydrogen-helium immiscibility in Jupiter
New Phases of Water Ice Predicted at Megabar Pressures
Based on density functional calculations we predict water ice to attain two
new crystal structures with Pbca and Cmcm symmetry at 7.6 and 15.5 Mbar,
respectively. The known high pressure ice phases VII, VIII, X, and Pbcm as well
as the Pbca phase are all insulating and composed of two interpenetrating
hydrogen bonded networks, but the Cmcm structure is metallic and consists of
corrugated sheets of H and O atoms. The H atoms are squeezed into octahedral
positions between next-nearest O atoms while they occupy tetrahedral positions
between nearest O atoms in the ice X, Pbcm, and Pbca phases.Comment: submitted to Physical Review Letters on Jan 25, 201
New journal: Algorithms for Molecular Biology
This editorial announces Algorithms for Molecular Biology, a new online open access journal published by BioMed Central. By launching the first open access journal on algorithmic bioinformatics, we provide a forum for fast publication of high-quality research articles in this rapidly evolving field. Our journal will publish thoroughly peer-reviewed papers without length limitations covering all aspects of algorithmic data analysis in computatioal biology. Publications in Algorithms for Molecular Biology are easy to find, highly visible and tracked by organisations such as PubMed. An established online submission system makes a fast reviewing procedure possible and enables us to publish accepted papers without delay. All articles published in our journal are permanently archived by PubMed Central and other scientific archives. We are looking forward to receiving your contributions
Stellenwert der pelvinen Lymphadenektomie beim klinisch lokalisierten Prostatakarzinom
Zusammenfassung: Der Stellenwert und die Ausdehnung der pelvinen Lymphadenektomie beim klinisch lokalisierten Prostatakarzinom werden weiterhin kontrovers diskutiert. Die Lymphadenektomie stellt jedoch bis heute die einzige Methode für ein exaktes Tumorstaging dar. Es gibt zunehmend Hinweise, dass das Entfernen von allen befallenen Lymphknoten einen positiven Einfluss auf das tumorfreie Überleben und evtl. auf das Gesamtüberleben haben könnte. Aus diesem Grund sollte, wenn eine Lymphadenektomie durchgeführt wird, diese Entlang der V.iliaca externa, in der Fossa obturatoria und beidseits Entlang der A.iliaca interna erfolge
Universal spectral statistics in Wigner-Dyson, chiral and Andreev star graphs II: semiclassical approach
A semiclassical approach to the universal ergodic spectral statistics in
quantum star graphs is presented for all known ten symmetry classes of quantum
systems. The approach is based on periodic orbit theory, the exact
semiclassical trace formula for star graphs and on diagrammatic techniques. The
appropriate spectral form factors are calculated upto one order beyond the
diagonal and self-dual approximations. The results are in accordance with the
corresponding random-matrix theories which supports a properly generalized
Bohigas-Giannoni-Schmit conjecture.Comment: 15 Page
Rotating Boson Stars in 5 Dimensions
We study rotating boson stars in five spacetime dimensions. The boson fields
consist of a complex doublet scalar field. Considering boson stars rotating in
two orthogonal planes with both angular momenta of equal magnitude, a special
ansatz for the boson field and the metric allows for solutions with nontrivial
dependence on the radial coordinate only. The charge of the scalar field equals
the sum of the angular momenta. The rotating boson stars are globally regular
and asymptotically flat. For our choice of a sixtic potential the rotating
boson star solutions possess a flat spacetime limit. We study the solutions in
flat and curved spacetime.Comment: 17 pages, 6 figure
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