5,446 research outputs found
Can’t Get Here from There: The Decision to Apply to a Selective Institution
Students from low-income families are greatly underrepresented at selective colleges and universities in the United States. In an attempt to increase applications from low-income students, some institutions have developed programs involving increased recruitment of and more attractive financial aid packages for students from low-income families. However, relatively little research has looked at the factors that are important in the college application decision-making process, and in particular how the importance of some factors may be different for low-income students. This paper uses data from the National Education Longitudinal Study of 1988 and the National Longitudinal Survey of Youth, 1997 cohort to analyze the factors influencing students\u27 college application decisions, with a focus on the decision to apply to a selective four-year institution. We analyze how the influence of distance from a student’s home during high school to a selective college or university and average tuition levels at selective institutions located nearby vary with the a student’s family income. Our results show that the further a student lives from a selective college, the less likely they are to apply to one, and this effect seems to be stronger than that of average tuition levels in the student’s state. Although the effect of distance does not differ for low-income students, they are most heavily impacted due to the geographic mismatch of low-income students and selective institutions. Personal, family (in particular, parent’s education) and high school characteristics also prove to be very influential when students are deciding whether or not to apply to a selective institution
Accounting of computer system use in EXEC 8
EXEC 8 modified multiprogramming system to log core time and central processing uni
Effective field theory approach to Casimir interactions on soft matter surfaces
We utilize an effective field theory approach to calculate Casimir
interactions between objects bound to thermally fluctuating fluid surfaces or
interfaces. This approach circumvents the complicated constraints imposed by
such objects on the functional integration measure by reverting to a point
particle representation. To capture the finite size effects, we perturb the
Hamiltonian by DH that encapsulates the particles' response to external fields.
DH is systematically expanded in a series of terms, each of which scales
homogeneously in the two power counting parameters: \lambda \equiv R/r, the
ratio of the typical object size (R) to the typical distance between them (r),
and delta=kB T/k, where k is the modulus characterizing the surface energy. The
coefficients of the terms in DH correspond to generalized polarizabilities and
thus the formalism applies to rigid as well as deformable objects.
Singularities induced by the point particle description can be dealt with using
standard renormalization techniques. We first illustrate and verify our
approach by re-deriving known pair forces between circular objects bound to
films or membranes. To demonstrate its efficiency and versatility, we then
derive a number of new results: The triplet interactions present in these
systems, a higher order correction to the film interaction, and general scaling
laws for the leading order interaction valid for objects of arbitrary shape and
internal flexibility.Comment: 4 pages, 1 figur
Sneutrino Dark Matter: Symmetry Protection and Cosmic Ray Anomalies
We present an R-parity conserving model of sneutrino dark matter within a
Higgs-philic U(1)' extension of the minimal supersymmetric standard model. In
this theory, the mu parameter and light Dirac neutrino masses are generated
naturally upon the breaking of the U(1)' gauge symmetry. The leptonic and
hadronic decays of sneutrinos in this model, taken to be the lightest and
next-to-lightest superpartners, allow for a natural fit to the recent results
reported by the PAMELA experiment.Comment: Revised to match the published version; 11 pages (2 column format), 1
table, 6 figures, to appear in PR
High Energy Field Theory in Truncated AdS Backgrounds
In this letter we show that, in five-dimensional anti-deSitter space (AdS)
truncated by boundary branes, effective field theory techniques are reliable at
high energy (much higher than the scale suggested by the Kaluza-Klein mass
gap), provided one computes suitable observables. We argue that in the model of
Randall and Sundrum for generating the weak scale from the AdS warp factor, the
high energy behavior of gauge fields can be calculated in a {\em cutoff
independent manner}, provided one restricts Green's functions to external
points on the Planck brane. Using the AdS/CFT correspondence, we calculate the
one-loop correction to the Planck brane gauge propagator due to charged bulk
fields. These effects give rise to non-universal logarithmic energy dependence
for a range of scales above the Kaluza-Klein gap.Comment: LaTeX, 7 pages; minor typos fixe
Next to leading order spin-orbit effects in the motion of inspiralling compact binaries
Using effective field theory (EFT) techniques we calculate the
next-to-leading order (NLO) spin-orbit contributions to the gravitational
potential of inspiralling compact binaries. We use the covariant spin
supplementarity condition (SSC), and explicitly prove the equivalence with
previous results by Faye et al. in arXiv:gr-qc/0605139. We also show that the
direct application of the Newton-Wigner SSC at the level of the action leads to
the correct dynamics using a canonical (Dirac) algebra. This paper then
completes the calculation of the necessary spin dynamics within the EFT
formalism that will be used in a separate paper to compute the spin
contributions to the energy flux and phase evolution to NLO.Comment: 25 pages, 4 figures, revtex4. v2: minor changes, refs. added. To
appear in Class. Quant. Gra
A nonlinear scalar model of extreme mass ratio inspirals in effective field theory I. Self force through third order
The motion of a small compact object in a background spacetime is
investigated in the context of a model nonlinear scalar field theory. This
model is constructed to have a perturbative structure analogous to the General
Relativistic description of extreme mass ratio inspirals (EMRIs). We apply the
effective field theory approach to this model and calculate the finite part of
the self force on the small compact object through third order in the ratio of
the size of the compact object to the curvature scale of the background (e.g.,
black hole) spacetime. We use well-known renormalization methods and
demonstrate the consistency of the formalism in rendering the self force finite
at higher orders within a point particle prescription for the small compact
object. This nonlinear scalar model should be useful for studying various
aspects of higher-order self force effects in EMRIs but within a comparatively
simpler context than the full gravitational case. These aspects include
developing practical schemes for higher order self force numerical
computations, quantifying the effects of transient resonances on EMRI waveforms
and accurately modeling the small compact object's motion for precise
determinations of the parameters of detected EMRI sources.Comment: 30 pages, 8 figure
Identification of Functionally Distinct TRAF Proinflammatory and PI3K/MEK Transforming Activities Emanating from the RET/PTC Fusion Oncoprotein
Thyroid carcinomas that harbor RET/PTC oncogenes are well differentiated, relatively benign neoplasms compared with those expressing oncogenic RAS or BRAF mutations despite signaling through shared transforming pathways. A distinction, however, is that RET/PTCs induce immunostimulatory programs, suggesting that, in the case of this tumor type, the additional pro-inflammatory pathway reduces aggressiveness. Here, we demonstrate that pro-inflammatory programs are selectively activated by TRAF2 and TRAF6 association with RET/PTC oncoproteins. Eliminating this mechanism reduces pro-inflammatory cytokine production without decreasing transformation efficiency. Conversely, ablating MEK/ERK or PI3K/AKT signaling eliminates transformation but not pro-inflammatory cytokine secretion. Functional uncoupling of the two pathways demonstrates that intrinsic pro-inflammatory pathways are not required for cellular transformation and suggests a need for further investigation into the role inflammation plays in thyroid tumor progression
Non-Abelian Conversion and Quantization of Non-scalar Second-Class Constraints
We propose a general method for deformation quantization of any second-class
constrained system on a symplectic manifold. The constraints determining an
arbitrary constraint surface are in general defined only locally and can be
components of a section of a non-trivial vector bundle over the phase-space
manifold. The covariance of the construction with respect to the change of the
constraint basis is provided by introducing a connection in the ``constraint
bundle'', which becomes a key ingredient of the conversion procedure for the
non-scalar constraints. Unlike in the case of scalar second-class constraints,
no Abelian conversion is possible in general. Within the BRST framework, a
systematic procedure is worked out for converting non-scalar second-class
constraints into non-Abelian first-class ones. The BRST-extended system is
quantized, yielding an explicitly covariant quantization of the original
system. An important feature of second-class systems with non-scalar
constraints is that the appropriately generalized Dirac bracket satisfies the
Jacobi identity only on the constraint surface. At the quantum level, this
results in a weakly associative star-product on the phase space.Comment: LaTeX, 21 page
On Writ of Certiorari to the United States Court of Appeals for the Ninth Circuit, Brief of Product Liability Advisory Council, Inc., National Association of Manufacturers, Business Roundtable, and Chemical Manufacturers Association as Amici Curiae in Support of Respondent, William Daubert and Joyce Daubert, Individually and as Guardians Ad Litem for Jason Daubert, and Anita De Young, Individually and as Gaurdian Ad Litem for Eric Schuller v. Merrell Dow Pharmaceuticals, Inc.
The Federal Rules of Evidence exclude expert scientific testimony when it has been developed without regard for accepted scientific methods.
This case focuses on expert scientific evidence. Such evidence plays a vital and often dispositive role in modern litigation. For scientific evidence to be helpful to the factfinder it must meet some minimal threshold of reliability. To hold otherwise would be to allow a system of adjudication based more on chance than on reason
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