At present, the authors think that a substantial fraction of the interstellar medium is filled with a hot (approximately 10 6 K) and diffuse 'coronal gas' (10 -3 cm -3 ). The case of streaming in HII regions was considered by Wentzel (1974) and Skilling (1975), and did not lead either to a satisfactory solution. Kulsrud and Cesarsky (1971) showed that, in such a medium, cosmic rays of energy >approximately100 GeV are not confined at all, because the waves are damped very rapidly by the effect of the collisions between the neutral and the charged particles in the medium. Until a few years ago, it was believed that the interstellar medium was mostly filled by a neutral gas, of density approximately 0.1 cm -3 and a temperature of several thousand degrees. =10) must reflect accretion of mantles within interstellar cloudsĬosmic-ray self-confinement in the hot phase of the interstellar medium This requires that (a) the density contrast between the cloud and intercloud medium be sufficiently high, and (b) the filling factor of the hot and tenuous gas of the interstellar medium, which presumably gives rise to the O VI absorption and soft X-ray emission, be nearly unity. In order to obtain significant (approx.3) depletions of metals presubably locked up in refractory grain cores, the destruction of grains that reside in the clouds must be minimal. Supernova blast waves expand predominantly in the hot and tenuous phase of the medium and are showed down as they propagate through a cloud. In a cloudy three-phase ISM most grains reside in the warm and cold phases of the medium. We find that in the standard two-phase model for the interstellar medium (ISM), grain destruction is very efficient, and the abundance of refractory grains should be negligible, contrary to observations. The calculations include a self-consistent treatment of red-giant winds, planetary nebulae, protostellar nebulae, and suprnovae as sources of grains and star formation, and of encounters with supernova blast waves as sinks. We have examined theoretically the evolution of refractory interstellar grain abundances and corresponding metal deplections in the solar neighborhood.
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In the practical aspect, the method is suitable for conformational analyses of large biomacromolecules and calculations of mechanical properties of biomaterials, which is demonstrated by the studied systems including an amyloid dimer, lysozyme and adenylate kinase proteins, and the S2 subdomain of myosin.Interstellar depletions and the filling factor of the hot interstellar medium The new approach is quite efficient since it avoids expensive atomistic molecular dynamics simulations and can start from already coarse-grained elastic network models. The method relies on the technique of fluctuation matching that has been devised earlier for parametrizing heterogeneous elastic network models based on data from atomistic molecular dynamics simulations. In the framework of normal-mode analysis, an arbitrary fine-grained model can be systematically converted to a more coarse-grained model, while the crucial low-frequency motions of the fine-grained system are able to be reproduced in the coarse-grained modeling.
A multiscale coarse-graining method called the normal-mode analysis based fluctuation matching (NMA-FM) is developed for constructing coarse-grained models of biomolecular systems.
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