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Review of Decolonizing the University, edited by Gurminder K. Bhambra, Dalia Gebrial, and Kerem Nişancıoğlu
Stress: Putting the Brain Back Into Medicine
Throughout the life course stress plays a major role in health and disease. Although it has long been known that the brain orchestrates the many ways that the body responds to these experiences, a gap exists between health care providers who focus from the head up and those who focus on the head down
Chaotic diffusion of the Vesta family induced by close encounters with massive asteroids
We numerically estimate the semi-major axis chaotic diffusion of the Vesta
family asteroids induced by close encounters with 11 massive main belt
asteroids : (1) Ceres, (2) Pallas, (3) Juno, (4) Vesta, (7) Iris, (10) Hygiea,
(15) Eunomia, (19) Fortuna, (324) Bamberga, (532) Herculina, (704) Interamnia.
We find that most of the diffusion is due to Ceres and Vesta. By extrapolating
our results, we are able to constrain the global effect of close encounters
with all the main belt asteroids. A comparison of this drift estimate with the
one expected for the Yarkovsky effect shows that for asteroids whose diameter
is larger than about 40 km, close encounters dominate the Yarkovsky effect.
Overall, our findings confirm the standard scenario for the history of the
Vesta family.Comment: 9 pages, 9 figures, 1 Table, submitte
Tidal dissipation and the formation of Kepler near-resonant planets
Multi-planetary systems detected by the Kepler mission present an excess of
planets close to first-order mean-motion resonances (2:1 and 3:2) but with a
period ratio slightly higher than the resonant value. Several mechanisms have
been proposed to explain this observation. Here we provide some clues that
these near-resonant systems were initially in resonance and reached their
current configuration through tidal dissipation. The argument that has been
opposed to this scenario is that it only applies to the close-in systems and
not to the farthest ones for which the tidal effect is too weak. Using the
catalog of KOI of the Kepler mission, we show that the distributions of period
ratio among the most close-in planetary systems and the farthest ones differ
significantly. This distance dependent repartition is a strong argument in
favor of the tidal dissipation scenario.Comment: 3 pages, 3 figures, submitted for publicatio
An Overview of Federal Support for Housing
The federal government commits substantial resources to support housing and mortgage markets through a combination of spending programs and tax expenditures (that is, subsidies conveyed through reductions in taxes). During the crisis of the past two years, the budgetary commitment expanded—to about $300 billion in fiscal year 2009—from the placement into conservatorship in September 2008 of the Federal National Mortgage Association (Fannie Mae) and the Federal Home Loan Mortgage Corporation (Freddie Mac) and the creation of new housing programs. This Congressional Budget Office (CBO) brief describes, in broad terms, the array of federal activities that support housing and the recent expansion of particular programs.
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