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Integrated single cell analysis of blood and cerebrospinal fluid leukocytes in multiple sclerosis
CP Violation in \tau ->\nu\pi K_S and D->\pi K_S: The Importance of K_S-K_L Interference
The -factories have measured CP asymmetries in the and
modes. The state is identified by its decay to two pions at
a time that is close to the lifetime. Within the Standard Model and many
of its extensions, the asymmetries in these modes come from CP violation in
mixing. We emphasize that the interference between the
amplitudes of intermediate and is as important as the pure
amplitude. Consequently, the measured asymmetries depend on the times over
which the relevant decay rates are integrated and on features of the
experiment.Comment: 4 pages, 4 figure
Noise Effects on the Complex Patterns of Abnormal Heartbeats
Patients at high risk for sudden death often exhibit complex heart rhythms in
which abnormal heartbeats are interspersed with normal heartbeats. We analyze
such a complex rhythm in a single patient over a 12-hour period and show that
the rhythm can be described by a theoretical model consisting of two
interacting oscillators with stochastic elements. By varying the magnitude of
the noise, we show that for an intermediate level of noise, the model gives
best agreement with key statistical features of the dynamics.Comment: 4 pages, 4 figures, RevTe
Magnitude and Sign Correlations in Heartbeat Fluctuations
We propose an approach for analyzing signals with long-range correlations by
decomposing the signal increment series into magnitude and sign series and
analyzing their scaling properties. We show that signals with identical
long-range correlations can exhibit different time organization for the
magnitude and sign. We find that the magnitude series relates to the nonlinear
properties of the original time series, while the sign series relates to the
linear properties. We apply our approach to the heartbeat interval series and
find that the magnitude series is long-range correlated, while the sign series
is anticorrelated and that both magnitude and sign series may have clinical
applications.Comment: 4 pages,late
Final State Interactions and New Physics in B -> pi K Decays
Within the Standard Model, and if one assumes that soft rescattering effects
are negligible, the CP asymmetry A^dir_CP (B^\pm -> \pi^\pm K) is predicted to
be very small and the ratio R = BR(B_d -> \pi^\mp K^\pm)/BR(B^\pm -> \pi^\pm K)
provides a bound on the angle \gamma of the unitarity triangle, sin^2 \gamma
\leq R. We estimate the corrections from soft rescattering effects using an
approach based on Regge phenomenology, and find effects of order 10% with large
uncertainties. In particular, we conclude that A^dir_CP \sim 0.2 and sin^2
\gamma \sim 1.2 R could not be taken unambiguously to signal New Physics. Using
SU(3) relations, we suggest experimental tests that could constrain the size of
the soft rescattering effects thus reducing the related uncertainty. Finally,
we study the effect of various models of New Physics on A^dir_CP and on R.Comment: 20 pages, RevTex, no figures; a few typos corrected, references
added, brief additional discussion of uncertanties is adde
Testing the Standard Model and Schemes for Quark Mass Matrices with CP Asymmetries in B Decays
The values of and , where and
are angles of the unitarity triangle, will be readily measured in a B
factory (and maybe also in hadron colliders). We study the standard model
constraints in the plane. We use the results
from recent analyses of and which take into account
heavy quark symmetry considerations. We find and
most likely \sin (2 \beta) \roughly{>} 0.6, and emphasize the strong
correlations between and . Various schemes
for quark mass matrices allow much smaller areas in the plane. We study the schemes of Fritzsch, of Dimopoulos, Hall and
Raby, and of Giudice, as well as the ``symmetric CKM'' idea, and show how CP
asymmetries in B decays will crucially test each of these schemes.Comment: 11 pages and 4 postscript figures available on request, LaTeX,
WIS-92/52/Jun-PH, LBL-3256
Modeling resilience and sustainability in ancient agricultural systems
The reasons why people adopt unsustainable agricultural practices, and the ultimate environmental implications of those practices, remain incompletely understood in the present world. Archaeology, however, offers unique datasets on coincident cultural and ecological change, and their social and environmental effects. This article applies concepts derived from ecological resilience thinking to assess the sustainability of agricultural practices as a result of long-term interactions between political, economic, and environmental systems. Using the urban center of Gordion, in central Turkey, as a case study, it is possible to identify mismatched social and ecological processes on temporal, spatial, and organizational scales, which help to resolve thresholds of resilience. Results of this analysis implicate temporal and spatial mismatches as a cause for local environmental degradation, and increasing extralocal economic pressures as an ultimate cause for the adoption of unsustainable land-use practices. This analysis suggests that a research approach that integrates environmental archaeology with a resilience perspective has considerable potential for explicating regional patterns of agricultural change and environmental degradation in the past
Comparisons of binary black hole merger waveforms
This a particularly exciting time for gravitational wave physics.
Ground-based gravitational wave detectors are now operating at a sensitivity
such that gravitational radiation may soon be directly detected, and recently
several groups have independently made significant breakthroughs that have
finally enabled numerical relativists to solve the Einstein field equations for
coalescing black-hole binaries, a key source of gravitational radiation. The
numerical relativity community is now in the position to begin providing
simulated merger waveforms for use by the data analysis community, and it is
therefore very important that we provide ways to validate the results produced
by various numerical approaches. Here, we present a simple comparison of the
waveforms produced by two very different, but equally successful
approaches--the generalized harmonic gauge and the moving puncture methods. We
compare waveforms of equal-mass black hole mergers with minimal or vanishing
spins. The results show exceptional agreement for the final burst of radiation,
with some differences attributable to small spins on the black holes in one
case.Comment: Revtex 4, 5 pages. Published versio
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