20,040 research outputs found
The flat space S-matrix from the AdS/CFT correspondence?
We investigate recovery of the bulk S-matrix from the AdS/CFT correspondence,
at large radius. It was recently argued that some of the elements of the
S-matrix might be read from CFT correlators, given a particular singularity
structure of the latter, but leaving the question of more general S-matrix
elements. Since in AdS/CFT, data must be specified on the boundary, we find
certain limitations on the corresponding bulk wavepackets and on their
localization properties. In particular, those we have found that approximately
localize have low-energy tails, and corresponding power-law tails in position
space. When their scattering is compared to that of "sharper" wavepackets
typically used in scattering theory, one finds apparently significant
differences, suggesting a possible lack of resolution via these wavepackets. We
also give arguments that construction of the sharper wavepackets may require
non-perturbative control of the boundary theory, and particular of the N^2
matrix degrees of freedom. These observations thus raise interesting questions
about what principle would guarantee the appropriate control, and about how a
boundary CFT can accurately approximate the flat space S-matrix.Comment: 26 pages. v2: typos fixed v3: minor improvements in discussio
Earnings Dynamics and Inequality among Canadian Men, 1976-1992: Evidence from Longitudinal Income Tax Records
Several recent studies have found that earnings inequality in Canada has grown considerably since the late 1970's. Using an extraordinary data base drawn from longitudinal income tax records, we decompose this growth in earnings inequality into its persistent and transitory components. We find that the growth in earnings inequality reflects both an increase in long-run inequality and an increase in earnings instability. The large size of our earnings panel allows us to estimate and test richer models of earnings dynamics than could be supported by the relatively small panel surveys used in U.S. research. The Canadian data strongly reject several restrictions commonly imposed in the U.S. literature, and they also suggest that imposing these evidently false restrictions may lead to distorted inferences about earnings dynamics and inequality trends.
Earnings Dynamics and Inequality among Canadian Men, 1976-1992: Evidence from Longitudinal Income Tax Records
Several recent studies have found that earnings inequality in Canada has grown considerably since the late 1970's. Using an extraordinary data base drawn from longitudinal income tax records, we decompose this growth in earnings inequality into its persistent and transitory components. We find that the growth in earnings inequality reflects both an increase in long-run inequality and an increase in earnings instability. Our large sample size enables us to estimate and test richer models than could be supported by the relatively small panel surveys used in most previous research on earnings dynamics. For example, we are able to incorporate both heterogeneous earnings growth and a random-walk process in the same model, and we find that both are empirically significant.
2012-13 Arkansas Test Results
In early August, the Arkansas Department of Education (ADE) released the 2012-2013 test score results. The following brief will highlight the results of these tests, compare achievement scores over time, and provide a glimpse of regional achievement results for the following exams: Benchmark Exam (Grades 3-8) End-of-Course Exam (Algebra I, Geometry, Biology, and Grade 11 Literacy). Iowa Test of Basic Skills (Grades 1-9
Residential broadband subscription demand: an econometric analysis of Australian choice experiment data
The recent roll-out of fibre-optic cable suggests that the willingness of households in passed communities to subscribe to networked services is an important issue. This paper studies the determination of the demand for network subscription. Through a discrete choice model the effect of installation and rental price on the likelihood of subscription is analysed. The logit regression is based on choice experiment (stated preference)subscription data obtained from a national survey of households. Limitations of this preliminary work and suggestions for future research are discussed.Broadband subscription demand
Visualizing mitochondrial FoF1-ATP synthase as the target of the immunomodulatory drug Bz-423
Targeting the mitochondrial enzyme FoF1-ATP synthase and modulating its
catalytic activities with small molecules is a promising new approach for
treatment of autoimmune diseases. The immuno-modulatory compound Bz-423 is such
a drug that binds to subunit OSCP of the mitochondrial FoF1-ATP synthase and
induces apoptosis via increased reactive oxygen production in coupled, actively
respiring mitochondria. Here we review the experimental progress to reveal the
binding of Bz-423 to the mitochondrial target and discuss how subunit rotation
of FoF1-ATP synthase is affected by Bz-423. Briefly, we report how F\"orster
resonance energy transfer (FRET) can be employed to colocalize the enzyme and
the fluorescently tagged Bz-423 within the mitochondria of living cells with
nanometer resolution.Comment: 10 pages, 2 figure
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