50,964 research outputs found
Schechter vs. Schechter: Sub-Arcsecond Gravitational Lensing and Inner Halo Profiles
Sub-arcsecond lensing statistics depend sensitively on the inner mass
profiles of low-mass objects and the faint-end slopes of the Schechter
luminosity function and the Press-Schechter mass function. By requiring the
luminosity and mass functions to give consistent predictions for the
distribution of image separation below 1'', we show that dark matter halos with
masses below 10^12 M_sun cannot have a single type of profile, be it the
singular isothermal sphere (SIS) or the shallower ``universal'' dark matter
profile. Instead, consistent results are achieved if we allow a fraction of the
halos at a given mass to be luminous with the SIS profile, and the rest be dark
with an inner logarithmic slope shallower than -1.5 to compensate for the
steeper faint-end slope of the mass function compared with the luminosity
function. We quantify how rapidly the SIS fraction must decrease with
decreasing halo mass, thereby providing a statistical measure for the
effectiveness of feedback processes on the baryon content in low-mass halos.Comment: 13 pages, 4 figures. CLASS lensing data added; minor revisions. ApJL
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Interpretation of HRCT Scans in the Diagnosis of IPF: Improving Communication Between Pulmonologists and Radiologists.
Idiopathic pulmonary fibrosis (IPF) is a progressive fibrosing interstitial lung disease (ILD). In this review, we describe the central role of high-resolution computed tomography (HRCT) in the diagnosis of IPF and discuss how communication between pulmonologists and radiologists might be improved to make the interpretation of HRCT scans more effective. Clinical information is important in the interpretation of HRCT scans, as the likelihood that specific radiologic features reflect IPF is not absolute, but dependent on the clinical context. In cases where the clinical context or HRCT pattern are inconclusive, multidisciplinary discussion (MDD) between a pulmonologist and radiologist (and, where relevant, a pathologist and rheumatologist) experienced in the differential diagnosis of ILD is necessary to establish a diagnosis. While it can be challenging to convene a face-to-face meeting, MDD can be conducted virtually or by telephone to enable each specialty group to contribute. To make the MDD most effective, it is important that relevant clinical information (for example, on the patient's clinical history, exposures and the results of serological tests) is shared with all parties in advance. A common lexicon to describe HRCT features observed in ILD can also help improve the effectiveness of MDD. A working diagnosis may be made in patients who do not fulfill all the diagnostic criteria for any specific type of ILD, but this diagnosis should be reviewed at regular intervals, with repeat of clinical, radiological, and laboratory assessments as appropriate, as new information pertinent to the patient's diagnosis may become available
Inclusive Production Through AdS/CFT
It has been shown that AdS/CFT calculations can reproduce certain exclusive
2->2 cross sections in QCD at high energy, both for near-forward and for
fixed-angle scattering. In this paper, we extend prior treatments by using
AdS/CFT to calculate the inclusive single-particle production cross section in
QCD at high center-of-mass energy. We find that conformal invariance in the UV
restricts the cross section to have a characteristic power-law falloff in the
transverse momentum of the produced particle, with the exponent given by twice
the conformal dimension of the produced particle, independent of incoming
particle types. We conclude by comparing our findings to recent LHC
experimental data from ATLAS and ALICE, and find good agreement.Comment: JHEP version. Discussion, appendix, figures, and tables added.
Conclusions and key results unchange
Hamiltonian formulation of SL(3) Ur-KdV equation
We give a unified view of the relation between the KdV, the mKdV, and
the Ur-KdV equations through the Fr\'{e}chet derivatives and their inverses.
For this we introduce a new procedure of obtaining the Ur-KdV equation, where
we require that it has no non-local operators. We extend this method to the
KdV equation, i.e., Boussinesq(Bsq) equation and obtain the hamiltonian
structure of Ur-Bsq equationin a simple form. In particular, we explicitly
construct the hamiltonian operator of the Ur-Bsq system which defines the
poisson structure of the system, through the Fr\'{e}chet derivative and its
inverse.Comment: 12 pages, KHTP-93-03 SNUTP-93-2
Random Feature Maps via a Layered Random Projection (LaRP) Framework for Object Classification
The approximation of nonlinear kernels via linear feature maps has recently
gained interest due to their applications in reducing the training and testing
time of kernel-based learning algorithms. Current random projection methods
avoid the curse of dimensionality by embedding the nonlinear feature space into
a low dimensional Euclidean space to create nonlinear kernels. We introduce a
Layered Random Projection (LaRP) framework, where we model the linear kernels
and nonlinearity separately for increased training efficiency. The proposed
LaRP framework was assessed using the MNIST hand-written digits database and
the COIL-100 object database, and showed notable improvement in object
classification performance relative to other state-of-the-art random projection
methods.Comment: 5 page
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