2,138 research outputs found
Review of: The Ethics of Reproductive Technology (Kenneth D. Alpern ed., Oxford University Press 1992)
Review of: The Ethics of Reproductive Technology (Kenneth D. Alpern ed., Oxford University Press 1992). Additional readings, glossary, introduction, notes, preface. LC 92-8252; ISBN 0-19-507435-1. [370 pp. Paper $19.95. 200 Madison Avenue, New York NY 10016.
The Effect of Skin-to-Skin Contact (Kangaroo Care) Shortly After Birth on the Neurobehavioral Responses of the Term Newborn: A Randomized, Controlled Trial
Enhancing Robustness and Immunization in geographical networks
We find that different geographical structures of networks lead to varied
percolation thresholds, although these networks may have similar abstract
topological structures. Thus, the strategies for enhancing robustness and
immunization of a geographical network are proposed. Using the generating
function formalism, we obtain the explicit form of the percolation threshold
for networks containing arbitrary order cycles. For 3-cycles, the
dependence of on the clustering coefficients is ascertained. The analysis
substantiates the validity of the strategies with an analytical evidence.Comment: 6 pages, 8 figure
Good Windbreaks Help Increase South Dakota Crop Yields
The use of field windbreaks as a soil conservation practice in the Plains States has progressed steadily during the past 20 years. These plantings reward their owners with numerous benefits, including the reduction of wind currents, soil drifting, crop blowout, evaporation, transpiration, and control of drifting snow. In many cases they also provide protection for livestock and wildlife and produce wood products and fruit for home use. Many farmers have also observed increased crop yields in areas protected by windbreaks. Little research data are available on this phase. To get more information, employees of the Soil Conservation Service interviewed representative South Dakota farmers during the fall of 1954 to obtain firsthand results on the use of field windbreaks2 for increasing crop yields
Multifractality of Brownian motion near absorbing polymers
We characterize the multifractal behavior of Brownian motion in the vicinity
of an absorbing star polymer. We map the problem to an O(M)-symmetric
phi^4-field theory relating higher moments of the Laplacian field of Brownian
motion to corresponding composite operators. The resulting spectra of scaling
dimensions of these operators display the convexity properties which are
necessarily found for multifractal scaling but unusual for power of field
operators in field theory. Using a field-theoretic renormalization group
approach we obtain the multifractal spectrum for absorbtion at the core of a
polymer star as an asymptotic series. We evaluate these series using
resummation techniques.Comment: 18 pages, revtex, 6 ps-figure
Conversion of bright magneto-optical resonances into dark at fixed laser frequency for D2 excitation of atomic rubidium
Nonlinear magneto-optical resonances on the hyperfine transitions belonging
to the D2 line of rubidium were changed from bright to dark resonances by
changing the laser power density of the single exciting laser field or by
changing the vapor temperature in the cell. In one set of experiments atoms
were excited by linearly polarized light from an extended cavity diode laser
with polarization vector perpendicular to the light's propagation direction and
magnetic field, and laser induced fluorescence (LIF) was observed along the
direction of the magnetic field, which was scanned. A low-contrast bright
resonance was observed at low laser power densities when the laser was tuned to
the Fg=2 --> Fe=3 transition of Rb-87 and near to the Fg=3 --> Fe=4 transition
of Rb-85. The bright resonance became dark as the laser power density was
increased above 0.6mW/cm2 or 0.8 mW/cm2, respectively. When the Fg=2 --> Fe=3
transition of Rb-87 was excited with circularly polarized light in a second set
of experiments, a bright resonance was observed, which became dark when the
temperature was increased to around 50C. The experimental observations at room
temperature could be reproduced with good agreement by calculations based on a
theoretical model, although the theoretical model was not able to describe
measurements at elevated temperatures, where reabsorption was thought to play a
decisive role. The model was derived from the optical Bloch equations and
included all nearby hyperfine components, averaging over the Doppler profile,
mixing of magnetic sublevels in the external magnetic field, and a treatment of
the coherence properties of the exciting radiation field.Comment: 9 pages, 7 figure
Mini-Proceedings of the 15th meeting of the Working Group on Rad. Corrections and MC Generators for Low Energies
The mini-proceedings of the 15th Meeting of the "Working Group on Rad.
Corrections and MC Generators for Low Energies" held in Mainz on April 11,
2014, are presented. These meetings, started in 2006, have as aim to bring
together experimentalists and theorists working in the fields of meson
transition form factors, hadronic contributions to and the
effective fine structure constant, and development of Monte Carlo generators
and Radiative Corrections for precision e+e- and tau physics.Comment: 21 pages, 7 contributions. Editors: S. E. Mueller and G. Venanzon
Lower bounds for the first eigenvalue of the magnetic Laplacian
We consider a Riemannian cylinder endowed with a closed potential 1-form A
and study the magnetic Laplacian with magnetic Neumann boundary conditions
associated with those data. We establish a sharp lower bound for the first
eigenvalue and show that the equality characterizes the situation where the
metric is a product. We then look at the case of a planar domain bounded by two
closed curves and obtain an explicit lower bound in terms of the geometry of
the domain. We finally discuss sharpness of this last estimate.Comment: Replaces in part arXiv:1611.0193
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