2,339 research outputs found
Experimental observation of a complex periodic window
The existence of a special periodic window in the two-dimensional parameter
space of an experimental Chua's circuit is reported. One of the main reasons
that makes such a window special is that the observation of one implies that
other similar periodic windows must exist for other parameter values. However,
such a window has never been experimentally observed, since its size in
parameter space decreases exponentially with the period of the periodic
attractor. This property imposes clear limitations for its experimental
detection.Comment: 4.2 pages, 4 figure
Crises in a dissipative Bouncing ball model
The dynamics of a bouncing ball model under the influence of dissipation is
investigated by using a two dimensional nonlinear mapping. When high
dissipation is considered, the dynamics evolves to different attractors. The
evolution of the basins of the attracting fixed points is characterized, as we
vary the control parameters. Crises between the attractors and their boundaries
are observed. We found that the multiple attractors are intertwined, and when
the boundary crisis between their stable and unstable manifolds occur, it
creates a successive mechanism of destruction for all attractors originated by
the sinks. Also, an impact physical crises is setup, and it may be useful as a
mechanism to reduce the number of attractors in the system
Genetic heterogeneity in breast cancer: the road to personalized medicine?
This is the final published version. It was originally published here: http://www.biomedcentral.com/1741-7015/11/151. DOI: 10.1186/1741-7015-11-151.More women die from breast cancer across the world today than from any other type of malignancy. The clinical course of breast cancer varies tremendously between patients. While some of this variability is explained by traditional clinico-pathological factors (including patient age, tumor stage, histological grade and estrogen receptor status), molecular profiling studies have defined breast cancer subtypes with distinct clinical outcomes. This mini-review considers recent studies which have used genomics technologies in an attempt to identify new biomarkers of prognosis and treatment response. These studies highlight the genetic heterogeneity that exists within breast cancers in space and time
Maximal acceleration or maximal accelerations?
We review the arguments supporting the existence of a maximal acceleration
for a massive particle and show that different values of this upper limit can
be predicted in different physical situations.Comment: 13 pages, Latex, to be published in Int. J. Mod. Phys.
Phase Diagram of Cold Polarized Fermi Gas in Two Dimensions
The superfluid phase diagrams of a two-dimensional cold polarized Fermi gas
in the BCS-BEC crossover are systematically and analytically investigated. In
the BCS-Leggett mean field theory, the transition from unpolarized superfluid
phase to normal phase is always of first order. For a homogeneous system, the
two critical Zeeman fields and the critical population imbalance are
analytically determined in the whole coupling parameter region, and the
superfluid-normal mixed phase is shown to be the ground state between the two
critical fields. The density profile in the presence of a harmonic trap
calculated in the local density approximation exhibits a shell structure, a
superfluid core at the center and a normal shell outside. For weak interaction,
the normal shell contains a partially polarized cloud with constant density
difference surrounded by a fully polarized state. For strong interaction, the
normal shell is totally in fully polarized state with a density profile
depending only on the global population imbalance. The di-fermion bound states
can survive in the whole highly imbalanced normal phase.Comment: V3: extended version according to referee's comment. 12 pages, 6
figures. Analytical results of density profile in trapped system are
reported; V4: Version accepted by Physical Review
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