Atomic-physics calculations of radiative cooling are used to develop criteria for the overstability of radiating shocks. Our calculations explain the measurement of shock overstability by Grun et al. [Phys. Rev. Lett. 66, 2738 (1991)]] and explain why the overstability was not observed in other experiments. The methodology described here can be especially useful in astrophysical situations where the relevant properties leading to an overstability can be measured spectroscopically, but the effective adiabatic index is harder to determine.
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http://dx.doi.org/10.1103/PhysRevLett.89.125002 | DOI Listing |
Endocr Relat Cancer
March 2018
Department of Biochemistry and Molecular BiologySchool of Basic Medical Sciences, Beijing Key Laboratory of Tumor Invasion and Metastasis Research, Institute of Cancer Research, Capital Medical University, Beijing, China
Sulforaphane (SFN) inhibited growth in many cancers, but its half-life is 2 h in circulation. However, its metabolites, sulforaphane-cysteine (SFN-Cys) and sulforaphane-N-acetyl-cysteine (SFN-NAC) had longer half-lives and decreased the cell viability in both dose- and time-dependent manners in human prostate cancer. Flow cytometry assay revealed that these two SFN metabolites induced apoptosis with the features such as vacuolization, disappeared nuclear envelope, nuclear agglutination and fragmentation via transmission electron microscopy observation.
View Article and Find Full Text PDFEur J Neurosci
August 2008
Oxford Centre for Computational Neuroscience, Oxford, UK.
We propose a top-down approach to the symptoms of obsessive-compulsive disorder (OCD) based on a statistical dynamical framework. An increased depth in the basins of attraction of attractor network states in the brain makes each state too stable, so that it tends to remain locked in that state and can not easily be moved on to another state. We suggest that the different symptoms that may be present in OCD could be related to changes of this type in different brain regions.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
November 2004
Space Science Division Code 7674L, Naval Research Laboratory, Washington, DC 20375, USA.
We give an analytic treatment of radiative cooling behind radiative shocks following solutions given by Chevalier and Imamura. We demonstrate that within the approximation of a steady state radiative shock, the radiative cooling laws Lambda is proportional to Talpha that give rise to the oscillatory instability modeled by Chevalier and Imamura in gamma=5/3 cooling gas are stable to the dynamical thin-shell overstability in this gas, and vice versa. We also show that the fundamental features of the dynamical overstability observed by Grun et al.
View Article and Find Full Text PDFPhys Rev Lett
September 2002
Space Science Division Code 7674L, Naval Research Laboratory, Washington, D.C. 20375, USA.
Atomic-physics calculations of radiative cooling are used to develop criteria for the overstability of radiating shocks. Our calculations explain the measurement of shock overstability by Grun et al. [Phys.
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