16,766 research outputs found
Diffusion and localization of relative strategy scores in the Minority Game
We study the equilibrium distribution of relative strategy scores of agents
in the asymmetric phase () of the basic Minority
Game using sign-payoff, with agents holding two strategies over
histories. We formulate a statistical model that makes use of the gauge freedom
with respect to the ordering of an agent's strategies to quantify the
correlation between the attendance and the distribution of strategies. The
relative score of the two strategies of an agent is described
in terms of a one dimensional random walk with asymmetric jump probabilities,
leading either to a static and asymmetric exponential distribution centered at
for fickle agents or to diffusion with a positive or negative drift for
frozen agents. In terms of scaled coordinates and the
distributions are uniquely given by and in quantitative agreement with
direct simulations of the game. As the model avoids the reformulation in terms
of a constrained minimization problem it can be used for arbitrary payoff
functions with little calculational effort and provides a transparent and
simple formulation of the dynamics of the basic Minority Game in the asymmetric
phase
Parametrization of translational surfaces
The algebraic translational surface is a typical modeling surface in computer
aided design and architecture industry. In this paper, we give a necessary and
sufficient condition for that algebraic surface having a standard parametric
representation and our proof is constructive. If the given algebraic surface is
translational, then we can compute a standard parametric representation for the
surface
Linking Induction and Transrepression of PPARβ/δ with Cellular Function
The copyrights of all papers published in this journal are retained by the respective authors as per the 'Creative Commons Attribution License' (http://creativecommons.org/licenses/by/3.0/).Peroxisome proliferator activated receptors (PPARs) are ligand-activated transcription factors and members of the nuclear hormone receptor superfamily. PPARβ/δ is ubiquitously expressed and has a central role in homeostasis, and has been suggested as a therapeutic target for a number of metabolic and cardiovascular disorders. This important nuclear receptor controls transcription under different modes of molecular activity which directly control the cellular function and fate of tissues. This complex activity of induction and transrepression of gene expression (with and without exogenous ligands) is poorly understood and yet understanding this molecular control through novel drug development would led to control over a key molecular switch in all cells. This review outlines the main molecular mechanisms of PPARβ/δ, and links the modes of activity to the signalling pathways in inflammation, proliferation and senescence, with the goal to understand how this will translate into novel drug design to control the PPARβ/δ molecular switch.Peer reviewe
An empirical calibration of nebular abundances based on the sulphur emission lines
We present an empirical calibration of nebular abundances based on the strong
emission lines of [SII] and [SIII] in the red part of the spectrum through the
definition of a sulphur abundance parameter S23. This calibration presents two
important advantages against the commonly used one based on the optical oxygen
lines: it remains single-valued up to abundances close to solar and is rather
independent of the degree of ionization of the nebula.Comment: 10 pages, 8 figures. Accepted for publication in MNRA
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