18,267 research outputs found
[Review of] Flore Zephir, Haitian Immigrants in Black American: A Sociological and Sociolinguistic Portrait
Zephir explores Haitians\u27 identification with Americans through the transitional nature of Haitians\u27 ethnicity, roles of languages, the roles of bilingual educational programs, the generational transmission of Haitian ethnicity, and Haitians\u27 and Black Americans\u27 relationships. For historians and sociologists who are unfamiliar with the history of Haiti and Haitians in American, this book is informative and insightful, especially because of its useful maps and tables. Scholars interested in migration and adaptation are provided with helpful demographic information on Haitians\u27 immigration and settlement in America. Very relevant is a critical discussion of Haiti\u27s history and the resulting effects in the behavior and attitudes of Haitian immigrants in New York
Short-lived lattice quasiparticles for strongly interacting fluids
It is shown that lattice kinetic theory based on short-lived quasiparticles
proves very effective in simulating the complex dynamics of strongly
interacting fluids (SIF). In particular, it is pointed out that the shear
viscosity of lattice fluids is the sum of two contributions, one due to the
usual interactions between particles (collision viscosity) and the other due to
the interaction with the discrete lattice (propagation viscosity). Since the
latter is {\it negative}, the sum may turn out to be orders of magnitude
smaller than each of the two contributions separately, thus providing a
mechanism to access SIF regimes at ordinary values of the collisional
viscosity. This concept, as applied to quantum superfluids in one-dimensional
optical lattices, is shown to reproduce shear viscosities consistent with the
AdS-CFT holographic bound on the viscosity/entropy ratio. This shows that
lattice kinetic theory continues to hold for strongly coupled hydrodynamic
regimes where continuum kinetic theory may no longer be applicable.Comment: 10 pages, 2 figure
Deflection of jets induced by jet-cloud & jet-galaxy interactions
The model first introduced by Raga & Canto (1996) in which astrophysical jets
are deflected on passing through an isothermal high density region is
generalised by taking into account gravitational effects on the motion of the
jet as it crosses the high density cloud. The problem is also generalised for
relativistic jets in which gravitational effects induced by the cloud are
neglected. Two further cases, classical and relativistic, are discussed for the
cases in which the jet is deflected on passing through the interstellar gas of
a galaxy in which a dark matter halo dominates the gravitational potential.
The criteria for the stability of jets due to the formation of internal
shocks are discussed.Comment: 8 pages, 5 figures, Accepted for publication in MNRA
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