571 research outputs found
Fractal Structure of Random Matrices
A multifractal analysis is performed on the universality classes of random
matrices and the transition ones.Our results indicate that the eigenvector
probability distribution is a linear sum of two chi-squared distribution
throughout the transition between the universality ensembles of random matrix
theory and Poisson
Polarized nuclear target based on parahydrogen induced polarization
We discuss a novel concept of a polarized nuclear target for accelerator
fixed-target scattering experiments, which is based on parahydrogen induced
polarization (PHIP). One may be able to reach a 33% free-proton polarization in
the ethane molecule. The potential advantages of such a target include
operation at zero magnetic field, fast (100 Hz) polarization reversal,
and operation with large intensity of an electron beam.Comment: 16 pages, 2 figure
The urokinase system of plasminogen activation and prognosis in 2780 breast cancer patients
The antigen levels of components of the urokinase-type plasminogen
activator (uPA) system of plasminogen activation are correlated with
prognosis in several types of cancers, including breast cancer. In the
present study involving 2780 patients with primary invasive breast cancer,
we have evaluated the prognostic importance of the four major components
of the uPA system [uPA, the receptor uPAR (CD87), and the inhibitors PAI-1
and PAI-2]. The antigen levels were determined by ELISA in cytosols
prepared from primary breast tumors. The levels of the four factors
significantly correlated with each other; the Spearman rank correlation
coefficients (r(s)) ranged from 0.32 (between PAI-2 and PAI-1 or uPAR) to
0.59 (between uPA and PAI-1). The median duration of follow-up of patients
still alive was 88 months. In the multivariate analyses for relapse-free
survival (RFS) and overall survival (OS), we defined a basic model
including age, menopausal status, tumor size and grade, lymph node status,
adjuvant therapy, and steroid hormone receptor status. uPA, uPAR, PAI-1,
and PAI-2 were considered as categorical variables, each with two cut
points that were established by isotonic regression analysis. Compared
with tumors with low levels, those with intermediate and high levels
showed a relative hazard rate (RHR) and 95% confidence interval (95% CI)
of 1.22 (1.02-1.45) and 1.69 (1.39-2.05) for uPA, and 1.32 (1.14-1.54) and
2.17 (1.74-2.70) for PAI-1, respectively, in multivariate analysis for RFS
in all patients. Compared with tumors with high PAI-2 levels, those with
intermediate and low levels showed a poor RFS with a RHR (95% CI) of 1.30
(1.14-1.48) and 1.76 (1.38-2.24), respectively. Similar results were
obtained in the multivariate analysis for OS in all patients. Furthermore,
uPA and PAI-1 were independent predictive factors of a poor RFS and OS in
node-negative and node-positive patients. PAI-2 also added to the
multivariate models for RFS in node-negative and node-positive patients,
and in the analysis for OS in node-negative patients. uPAR did not further
contribute to any of the multivariate models. A prognostic score was
calculated based on the estimates from the final multivariate model for
RFS. Using this score, the difference between the highest and lowest 10%
risk groups was 66% in the analysis for RFS at 10 years and 61% in the
analysis for OS. Moreover, separate prognostic scores were calculated for
node-negative and node-positive patients. In the 10% highest risk groups,
the proportion of disease-free patients was only 27 +/- 6% and 9 +/- 3% at
10 years for node-negative and node-positive patients, respectively. These
proportions were 86 +/- 4% and 61 +/- 6% for the corresponding 10% lowest
risk groups of relapse. We conclude that several components of the uPA
system are potential predictors of RFS and OS in patients with primary
invasive breast cancer. Knowledge of these factors could be helpful to
assess the individual risk of patients, to select various types of
adjuvant treatment and to identify patients who may benefit from targeted
therapies that are currently being developed
Observing Direct CP Violation in Untagged B-Meson Decays
Direct CP violation can exist in untagged B-meson decays to self-conjugate,
three-particle final states; it would be realized as a population asymmetry in
the untagged decay rate across the mirror line of the Dalitz plot of the
three-body decay. We explore the numerical size of this direct CP-violating
effect in a variety of B-meson decays to three pseudoscalar mesons; we show
that the resulting asymmetry is comparable to the partial rate asymmetry in the
analogous tagged decays, making the search for direct CP violation in the
untagged decay rate, for which greater statistics accrue, advantageous.Comment: 31 pages, REVTeX4, 1 eps figure, references added, typos corrected,
version to appear in PR
Exact Hypersurface-Homogeneous Solutions in Cosmology and Astrophysics
A framework is introduced which explains the existence and similarities of
most exact solutions of the Einstein equations with a wide range of sources for
the class of hypersurface-homogeneous spacetimes which admit a Hamiltonian
formulation. This class includes the spatially homogeneous cosmological models
and the astrophysically interesting static spherically symmetric models as well
as the stationary cylindrically symmetric models. The framework involves
methods for finding and exploiting hidden symmetries and invariant submanifolds
of the Hamiltonian formulation of the field equations. It unifies, simplifies
and extends most known work on hypersurface-homogeneous exact solutions. It is
shown that the same framework is also relevant to gravitational theories with a
similar structure, like Brans-Dicke or higher-dimensional theories.Comment: 41 pages, REVTEX/LaTeX 2.09 file (don't use LaTeX2e !!!) Accepted for
publication in Phys. Rev.
VLBI localization of FRB 20201124A and absence of persistent emission on milliarcsecond scales
Removing Discrete Ambiguities in CP Asymmetry Measurements
We discuss methods to resolve the ambiguities in CP violating phase angles
that are left when a measurement of is made. We show what
knowledge of hadronic quantities will be needed to fully resolve all such
ambiguities.Comment: 23 pages, revtex, no figure
Polyacetylenes from Notopterygium incisum–New Selective Partial Agonists of Peroxisome Proliferator-Activated Receptor-Gamma
Peroxisome proliferator-activated receptor gamma (PPARγ) is a key regulator of glucose and lipid metabolism and therefore an important pharmacological target to combat metabolic diseases. Since the currently used full PPARγ agonists display serious side effects, identification of novel ligands, particularly partial agonists, is highly relevant. Searching for new active compounds, we investigated extracts of the underground parts of Notopterygium incisum, a medicinal plant used in traditional Chinese medicine, and observed significant PPARγ activation using a PPARγ-driven luciferase reporter model. Activity-guided fractionation of the dichloromethane extract led to the isolation of six polyacetylenes, which displayed properties of selective partial PPARγ agonists in the luciferase reporter model. Since PPARγ activation by this class of compounds has so far not been reported, we have chosen the prototypical polyacetylene falcarindiol for further investigation. The effect of falcarindiol (10 µM) in the luciferase reporter model was blocked upon co-treatment with the PPARγ antagonist T0070907 (1 µM). Falcarindiol bound to the purified human PPARγ receptor with a Ki of 3.07 µM. In silico docking studies suggested a binding mode within the ligand binding site, where hydrogen bonds to Cys285 and Glu295 are predicted to be formed in addition to extensive hydrophobic interactions. Furthermore, falcarindiol further induced 3T3-L1 preadipocyte differentiation and enhanced the insulin-induced glucose uptake in differentiated 3T3-L1 adipocytes confirming effectiveness in cell models with endogenous PPARγ expression. In conclusion, we identified falcarindiol-type polyacetylenes as a novel class of natural partial PPARγ agonists, having potential to be further explored as pharmaceutical leads or dietary supplements
PRECISE detects high activity from FRB 20220912A at 1.4 GHz but no bursts at 5 GHz using the Effelsberg telescope
PRECISE detects high activity from FRB 20220912A at 1.4 GHz but no bursts at 5 GHz using the Effelsberg telescope
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