31,273,683 research outputs found
A Formative Assessment of Geologic Time for High School Earth Science Students
Provides pedagogical insight concerning the assessment strategy using formative assessment The resource being annotated is: http://www.dlese.org/dds/catalog_DLESE-000-000-004-784.htm
New Physics in b --> s bar(s) s Decay
We perform a model-independent analysis of the data on branching ratios and
CP asymmetries of and modes. The present
data is encouraging to look for indirect evidences of physics beyond the
Standard Model. We investigate the parameter spaces for different possible
Lorentz structures of the new physics four-Fermi interaction. It is shown that
if one takes the data at confidence level, only one particular
Lorentz structure is allowed. Possible consequences for the system are
also discussed.Comment: 9 pages, 3 encapsulated figures, minor changes in the text,
conclusions unchanged, a few references added, version to appear in PL
Color suppressed contributions to the decay modes B_{d,s} -> D_{s,d} D_{s,d}, B_{d,s} -> D_{s,d} D^*_{s,d}, and B_{d,s} -> D^*_{s,d} D^*_{s,d}
The amplitudes for decays of the type , have no
factorizable contributions, while , and have relatively small factorizable contributions
through the annihilation mechanism. The dominant contributions to the decay
amplitudes arise from chiral loop contributions and tree level amplitudes which
can be obtained in terms of soft gluon emissions forming a gluon condensate. We
predict that the branching ratios for the processes ,
and are all
of order , while ,
and are of
order . We obtain branching ratios for two 's in
the final state of order two times bigger.Comment: 15 pages, 4 figure
Dynamic (S,s) Economies
In this paper we provide a framework to study the aggregate dynamic behavior of an economy where individual units follow (S,s) policies. We characterize structural and stochastic heterogeneities that ensure convergence of the economy's aggregate to that of its frictionless counterpart, determine the speed at which convergence takes place, and describe the transitional dynamics of this economy. In particular, we consider a dynamic economy where agents differ in their initial positions within their bands and face both stochastic and structural heterogeneity; where the former refers to the presence of (unit specific) idiosyncratic shocks, and the latter to differences in the widths of units' (S,s) bands and their response to aggregate shocks. We study the evolution of the economy's aggregate and the evolution of the difference between this aggregate and that of an economy without macroeconomic friction, where the latter pertains to a situation where individual units adjust with no delay to all shocks. We also examine the sensitivity of this difference to common shocks. For example, in the retail inventory problem the aggregate deviation and sensitivity to common shocks correspond to the aggregate inventory level and its sensitivity to aggregate demand shocks, respectively.
Coulomb effects in a ballistic one-channel S-S-S device
We develop a theory of Coulomb oscillations in superconducting devices in the
limit of small charging energy . We consider a small
superconducting grain of finite capacity connected to two superconducting leads
by nearly ballistic single-channel quantum point contacts. The temperature is
supposed to be very low, so there are no single-particle excitations on the
grain. Then the behavior of the system may be described as quantum mechanics of
the superconducting phase on the island. The Josephson energy as a function of
this phase has two minima which become degenerate at the phase difference on
the leads equal to , the tunneling amplitude between them being controlled
by the gate voltage at the grain. We find the Josephson current and its
low-frequency fluctuations and predict their periodic dependence on the induced
charge with period .Comment: 11 pages, REVTeX, 10 figures, uses eps
2-aminophenols containing electron-withdrawing groups from N-aryl hydroxylamines
Reaction of substituted N-aryl hydroxylamines with methanesulfonyl chloride, p-toluenesulfonyl chloride, or trifluoromethanesulfonic anhydride under basic conditions leads to the rearranged 2-aminophenols (45-94%). The overall reaction sequence can be performed using polymer-supported sulfonyl chloride resin allowing for the effective conversion of N-aryl hydroxylamines to the 2-aminophenols without the need for chromatography
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