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Redistributing toward the rich: Strategic policy crafting in the campaign to repeal the Sixteenth Amendment, 1938-1958
Beginning in 1938, some American business groups campaigned to repeal the Sixteenth Amendment and limit the federal taxation of income and wealth. Although their proposed upward-redistributive policy would benefit few voters, it won the support of 31 state legislatures. To explain this outcome, this article offers a theory of strategic policy crafting by advocacy groups. Such groups may succeed even in otherwise unfavorable institutional environments if they craft their proposals to fit the salient policy context. Archival evidence and event history analysis support this hypothesis. Public opinion also helps explain legislative support for upward-redistributive policy. © 2010 by The University of Chicago. All rights reserved
Factorization and NNLL Resummation for Higgs Production with a Jet Veto
Using methods of effective field theory, we derive the first all-order
factorization theorem for the Higgs-boson production cross section with a jet
veto, imposed by means of a standard sequential recombination jet algorithm.
Like in the case of small-q_T resummation in Drell-Yan and Higgs production,
the factorization is affected by a collinear anomaly. Our analysis provides the
basis for a systematic resummation of large logarithms log(m_H/p_T^veto) beyond
leading-logarithmic order. Specifically, we present predictions for the
resummed jet-veto cross section and efficiency at next-to-next-to-leading
logarithmic order. Our results have important implications for Higgs-boson
searches at the LHC, where a jet veto is required to suppress background
events.Comment: 28 pages, 5 figures; v2: published version; note added in proo
NLL+NNLO predictions for jet-veto efficiencies in Higgs-boson and Drell-Yan production
Using the technology of the CAESAR approach to resummation, we examine the
jet-veto efficiency in Higgs-boson and Drell-Yan production at hadron colliders
and show that at next-to-leading logarithmic (NLL) accuracy the resummation
reduces to just a Sudakov form factor. Matching with NNLO calculations results
in stable predictions for the case of Drell-Yan production, but reveals
substantial uncertainties in gluon-fusion Higgs production, connected in part
with the poor behaviour of the perturbative series for the total cross section.
We compare our results to those from POWHEG with and without reweighting by
HqT, as used experimentally, and observe acceptable agreement. In an appendix
we derive the part of the NNLL resummation corrections associated with the
radius dependence of the jet algorithm.Comment: 30 pages, 8 figures; v2 as published in JHE
Jet-veto in bottom-quark induced Higgs production at next-to-next-to-leading order
We present results for associated Higgs+n-jet production in bottom quark
annihilation, for n=0 and n>=1 at NNLO and NLO accuracy, respectively. We
consider both the cases with and without b-tagging. Numerical results are
presented for parameters relevant for experiments at the LHC.Comment: 27 pages, 13 figures, 8 table
The Quark Beam Function at NNLL
In hard collisions at a hadron collider the most appropriate description of
the initial state depends on what is measured in the final state. Parton
distribution functions (PDFs) evolved to the hard collision scale Q are
appropriate for inclusive observables, but not for measurements with a specific
number of hard jets, leptons, and photons. Here the incoming protons are probed
and lose their identity to an incoming jet at a scale \mu_B << Q, and the
initial state is described by universal beam functions. We discuss the
field-theoretic treatment of beam functions, and show that the beam function
has the same RG evolution as the jet function to all orders in perturbation
theory. In contrast to PDF evolution, the beam function evolution does not mix
quarks and gluons and changes the virtuality of the colliding parton at fixed
momentum fraction. At \mu_B, the incoming jet can be described perturbatively,
and we give a detailed derivation of the one-loop matching of the quark beam
function onto quark and gluon PDFs. We compute the associated NLO Wilson
coefficients and explicitly verify the cancellation of IR singularities. As an
application, we give an expression for the next-to-next-to-leading logarithmic
order (NNLL) resummed Drell-Yan beam thrust cross section.Comment: 54 pages, 9 figures; v2: notation simplified in a few places, typos
fixed; v3: journal versio
Factorization and resummation of s-channel single top quark production
In this paper we study the factorization and resummation of s-channel single
top quark production in the Standard Model at both the Tevatron and the LHC. We
show that the production cross section in the threshold limit can be factorized
into a convolution of hard function, soft function and jet function via
soft-collinear-effective-theory (SCET), and resummation can be performed using
renormalization group equation in the momentum space resummation formalism. We
find that in general, the resummation effects enhance the Next-to-Leading-Order
(NLO) cross sections by about at both the Tevatron and the LHC, and
significantly reduce the factorization scale dependence of the total cross
section at the Tevatron, while at the LHC we find that the factorization scale
dependence has not been improved, compared with the NLO results.Comment: 29 pages, 7 figures; version published in JHE
GPVI (Glycoprotein VI) Interaction With Fibrinogen Is Mediated by Avidity and the Fibrinogen αC-Region
Objective:
GPVI (glycoprotein VI) is a key molecular player in collagen-induced platelet signaling and aggregation. Recent evidence indicates that it also plays important role in platelet aggregation and thrombus growth through interaction with fibrin(ogen). However, there are discrepancies in the literature regarding whether the monomeric or dimeric form of GPVI binds to fibrinogen at high affinity. The mechanisms of interaction are also not clear, including which region of fibrinogen is responsible for GPVI binding. We aimed to gain further understanding of the mechanisms of interaction at molecular level and to identify the regions on fibrinogen important for GPVI binding.
Approach and Results:
Using multiple surface- and solution-based protein-protein interaction methods, we observe that dimeric GPVI binds to fibrinogen with much higher affinity and has a slower dissociation rate constant than the monomer due to avidity effects. Moreover, our data show that the highest affinity interaction of GPVI is with the αC-region of fibrinogen. We further show that GPVI interacts with immobilized fibrinogen and fibrin variants at a similar level, including a nonpolymerizing fibrin variant, suggesting that GPVI binding is independent of fibrin polymerization.
Conclusions:
Based on the above findings, we conclude that the higher affinity of dimeric GPVI over the monomer for fibrinogen interaction is achieved by avidity. The αC-region of fibrinogen appears essential for GPVI binding. We propose that fibrin polymerization into fibers during coagulation will cluster GPVI through its αC-region, leading to downstream signaling, further activation of platelets, and potentially stimulating clot growth
Stable Isotopic Evidence for Methane Seeps in Neoproterozoic Postglacial Cap Carbonates
The Earth's most severe glaciations are thought to have occurred about 600 million years ago, in the late Neoproterozoic era. A puzzling feature of glacial deposits from this interval is that they are overlain by 1–5-m-thick 'cap carbonates' (particulate deep-water marine carbonate rocks) associated with a prominent negative carbon isotope excursion. Cap carbonates have been controversially ascribed to the aftermath of almost complete shutdown of the ocean ecosystems for millions of years during such ice ages—the 'snowball Earth' hypothesis. Conversely, it has also been suggested that these carbonate rocks were the result of destabilization of methane hydrates during deglaciation and concomitant flooding of continental shelves and interior basins. The most compelling criticism of the latter 'methane hydrate' hypothesis has been the apparent lack of extreme isotopic variation in cap carbonates inferred locally to be associated with methane seeps. Here we report carbon isotopic and petrographic data from a Neoproterozoic postglacial cap carbonate in south China that provide direct evidence for methane-influenced processes during deglaciation. This evidence lends strong support to the hypothesis that methane hydrate destabilization contributed to the enigmatic cap carbonate deposition and strongly negative carbon isotopic anomalies following Neoproterozoic ice ages. This explanation requires less extreme environmental disturbance than that implied by the snowball Earth hypothesis
Crystal Structure of the RNA Recognition Motif of Yeast Translation Initiation Factor eIF3b Reveals Differences to Human eIF3b
BACKGROUND: The multi-subunit eukaryotic initiation factor3 (eIF3) plays a central role in the initiation step of protein synthesis in eukaryotes. One of its large subunits, eIF3b, serves as a scaffold within eIF3 as it interacts with several other subunits. It harbors an RNA Recognition Motif (RRM), which is shown to be a non-canonical RRM in human as it is not capable to interact with oligonucleotides, but rather interacts with eIF3j, a sub-stoichiometric subunit of eIF3. PRINCIPAL FINDING: We have analyzed the high-resolution crystal structure of the eIF3b RRM domain from yeast. It exhibits the same fold as its human ortholog, with similar charge distribution on the surface interacting with the eIF3j in human. Thermodynamic analysis of the interaction between yeast eIF3b-RRM and eIF3j revealed the same range of enthalpy change and dissociation constant as for the human proteins, providing another line of evidence for the same mode of interaction between eIF3b and eIF3j in both organisms. However, analysis of the surface charge distribution of the putative RNA-binding β-sheet suggested that in contrast to its human ortholog, it potentially could bind oligonucleotides. Three-dimensional positioning of the so called "RNP1" motif in this domain is similar to other canonical RRMs, suggesting that this domain might indeed be a canonical RRM, conferring oligonucleotide binding capability to eIF3 in yeast. Interaction studies with yeast total RNA extract confirmed the proposed RNA binding activity of yeast eIF3b-RRM. CONCLUSION: We showed that yeast eIF3b-RRM interacts with eIF3j in a manner similar to its human ortholog. However, it shows similarities in the oligonucleotide binding surface to canonical RRMs and interacts with yeast total RNA. The proposed RNA binding activity of eIF3b-RRM may help eIF3 to either bind to the ribosome or recruit the mRNA to the 43S pre-initiation complex
Quantum Measurement Theory in Gravitational-Wave Detectors
The fast progress in improving the sensitivity of the gravitational-wave (GW)
detectors, we all have witnessed in the recent years, has propelled the
scientific community to the point, when quantum behaviour of such immense
measurement devices as kilometer-long interferometers starts to matter. The
time, when their sensitivity will be mainly limited by the quantum noise of
light is round the corner, and finding the ways to reduce it will become a
necessity. Therefore, the primary goal we pursued in this review was to
familiarize a broad spectrum of readers with the theory of quantum measurements
in the very form it finds application in the area of gravitational-wave
detection. We focus on how quantum noise arises in gravitational-wave
interferometers and what limitations it imposes on the achievable sensitivity.
We start from the very basic concepts and gradually advance to the general
linear quantum measurement theory and its application to the calculation of
quantum noise in the contemporary and planned interferometric detectors of
gravitational radiation of the first and second generation. Special attention
is paid to the concept of Standard Quantum Limit and the methods of its
surmounting.Comment: 147 pages, 46 figures, 1 table. Published in Living Reviews in
Relativit
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