39,999 research outputs found
Med news
The Med News was a newsletter published from 1960-1962 by the Student American Medical Association (SAMA) at Boston University School of Medicine
Decay of protons and neutrons induced by acceleration
We investigate the decay of accelerated protons and neutrons. Calculations
are carried out in the inertial and coaccelerated frames. Particle
interpretation of these processes are quite different in each frame but the
decay rates are verified to agree in both cases. For sake of simplicity our
calculations are performed in a two-dimensional spacetime since our conclusions
are not conceptually affected by this.Comment: 18 pages (REVTEX), 3 figure
Search for semiclassical-gravity effects in relativistic stars
We discuss the possible influence of gravity in the neutronization process,
, which is particularly important as a cooling mechanism
of neutron stars. Our approach is semiclassical in the sense that leptonic
fields are quantized on a classical background spacetime, while neutrons and
protons are treated as excited and unexcited nucleon states, respectively. We
expect gravity to have some influence wherever the energy content carried by
the in-state is barely above the neutron mass. In this case the emitted
neutrinos would be soft enough to have a wavelength of the same order as the
space curvature radius.Comment: 10 pages (REVTEX
Some monetary facts
This article describes three long-run monetary facts derived by examining data for 110 countries over a 30-year period, using three definitions of a country's money supply and two subsamples of countries: (1) Growth rates of the money supply and the general price level are highly correlated for all three money definitions, for the full sample of countries, and for both subsamples. (2) The growth rates of money and real output are not correlated, except for a subsample of countries in the Organisation for Economic Co-operation and Development, where these growth rates are positively correlated. (3) The rate of inflation and the growth rate of real output are essentially uncorrelated. ; Reprinted in Quarterly Review, Fall 2001 (v. 25, no. 4)Money supply ; Monetary theory
Strategies to augment volitional and reflex function may improve locomotor capacity following incomplete spinal cord injury
Many studies highlight the remarkable plasticity demonstrated by spinal circuits following an incomplete spinal cord injury (SCI). Such plasticity can contribute to improvements in volitional motor recovery, such as walking function, although similar mechanisms underlying this recovery may also contribute to the manifestation of exaggerated responses to afferent input, or spastic behaviors. Rehabilitation interventions directed toward augmenting spinal excitability have shown some initial success in improving locomotor function. However, the potential effects of these strategies on involuntary motor behaviors may be of concern. In this article, we provide a brief review of the mechanisms underlying recovery of volitional function and exaggerated reflexes, and the potential overlap between these changes. We then highlight findings from studies that explore changes in spinal excitability during volitional movement in controlled conditions, as well as altered kinematic and behavioral performance during functional tasks. The initial focus will be directed toward recovery of reflex and volitional behaviors following incomplete SCI, followed by recent work elucidating neurophysiological mechanisms underlying patterns of static and dynamic muscle activation following chronic incomplete SCI during primarily single-joint movements. We will then transition to studies of locomotor function and the role of altered spinal integration following incomplete SCI, including enhanced excitability of specific spinal circuits with physical and pharmacological interventions that can modulate locomotor output. The effects of previous and newly developed strategies will need to focus on changes in both volitional function and involuntary spastic reflexes for the successful translation of effective therapies to the clinical setting
- …