4,050 research outputs found
Radio Polarization of BL Lacertae objects
In this paper, using the database of the university of Michigan Radio
Astronomy Observatory (UMRAO) at three (4.8 GHz, 8 GHZ, and 14.5 GHz) radio
frequencies, we studied the polarization properties for 47 BL Lacertae
objects(38 radio selected BL Lacertae objects, 7 X-ray selected BL Lacertae,
and two inter-middle objects (Mkn 421 and Mkn 501), and found that (1) The
polarizations at higher radio frequency is higher than those at lower
frequency, (2) The variability of polarization at higher radio frequency is
higher than those at lower frequency, (3) The polarization is correlated with
the radio spectral index, and (4) The polarization is correlated with
core-dominance parameter for those objects with known core-dominance parameters
suggesting that the relativistic beaming could explain the polarization
characteristic of BL Lacs.Comment: 5 pages, 3 figures, 1 table. PASJ, in pres
P-wave states: masses and pole residues
In this paper, we consider all P-wave states represented by
interpolating currents with a derivative and calculate the corresponding masses
and pole residues with the method of QCD sum rule. Due to the large
uncertainties in our calculation compared with the small difference in the
masses of the excited states observed by the LHCb collaboration,
it is necessary to study other properties of the P-wave states
represented by the interpolating currents investigated in the present work in
order to have a better understanding about the four excited states
observed by the LHCb collaboration.Comment: 14 pages, 8 figure
Effect of hydroxyurea on the promoter occupancy profiles of tumor suppressor p53 and p73
<p>Abstract</p> <p>Background</p> <p>The p53 tumor suppressor and its related protein, p73, share a homologous DNA binding domain, and mouse genetics studies have suggested that they have overlapping as well as distinct biological functions. Both p53 and p73 are activated by genotoxic stress to regulate an array of cellular responses. Previous studies have suggested that p53 and p73 independently activate the cellular apoptotic program in response to cytotoxic drugs. The goal of this study was to compare the promoter-binding activity of p53 and p73 at steady state and after genotoxic stress induced by hydroxyurea.</p> <p>Results</p> <p>We employed chromatin immunoprecipitation, the NimbleGen promoter arrays and a model-based algorithm for promoter arrays to identify promoter sequences enriched in anti-p53 or anti-p73 immunoprecipitates, either before or after treatment with hydroxyurea, which increased the expression of both p53 and p73 in the human colon cancer cell line HCT116-3(6). We calculated a model-based algorithm for promoter array score for each promoter and found a significant correlation between the promoter occupancy profiles of p53 and p73. We also found that after hydroxyurea treatment, the p53-bound promoters were still bound by p73, but p73 became associated with additional promoters that that did not bind p53. In particular, we showed that hydroxyurea induces the binding of p73 but not p53 to the promoter of <it>MLH3</it>, which encodes a mismatch repair protein, and causes an up-regulation of the <it>MLH3 </it>mRNA.</p> <p>Conclusion</p> <p>These results suggest that hydroxyurea exerts differential effects on the promoter-binding functions of p53 and p73 and illustrate the power of model-based algorithm for promoter array in the analyses of promoter occupancy profiles of highly homologous transcription factors.</p
On compression rate of quantum autoencoders: Control design, numerical and experimental realization
Quantum autoencoders which aim at compressing quantum information in a
low-dimensional latent space lie in the heart of automatic data compression in
the field of quantum information. In this paper, we establish an upper bound of
the compression rate for a given quantum autoencoder and present a learning
control approach for training the autoencoder to achieve the maximal
compression rate. The upper bound of the compression rate is theoretically
proven using eigen-decomposition and matrix differentiation, which is
determined by the eigenvalues of the density matrix representation of the input
states. Numerical results on 2-qubit and 3-qubit systems are presented to
demonstrate how to train the quantum autoencoder to achieve the theoretically
maximal compression, and the training performance using different machine
learning algorithms is compared. Experimental results of a quantum autoencoder
using quantum optical systems are illustrated for compressing two 2-qubit
states into two 1-qubit states
Due Process in Antitrust Enforcement: Normative and Comparative Perspectives
Due process in antitrust enforcement has significant implications for better professional and accurate enforcement decisions. Not only can due process spur economic growth, raise government credibility, and limit the abuse of powers according to law, it also promotes competitive reforms in monopolized sectors and curbs corruption. Jurisdictions learn from the best practices in the investigation process, decisionmaking process, and the announcement and judicial review of antitrust enforcement decisions. By comparing the enforcement policies of China, the European Union, and the United States, this article calls for better disclosure of evidence, participation of legal counsel, and protection of the procedural and substantive rights of the respondent in the investigation process. In conducting evidence review and arriving at punitive decisions, the enforcement agency should establish a separation between investigatory and adjudicatory functions. Finally, the issued punishment decision should contain more comprehensive information and be subject to judicial review
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