4,773 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
Process Decoupling of Plasma Enhanced Synthesis of Chlorinated Polyvinyl Chloride (CPVC) Particles in a Circulating Fluidized Bed
Plasma enhanced synthesis of CPVC particles in a gas-solid plasma circulating fluidized bed reactor (PCFBR) is proposed as a novel CPVC synthesizing method. The chlorination process is decoupled into a fast initiation step in a plasma riser and a slow chlorination process in the accompanying bed. The CPVC product has good properties in terms of chlorine content and microstructure
Exceptional entanglement in non-Hermitian fermionic models
Exotic singular objects, known as exceptional points, are ubiquitous in
non-Hermitian physics. They might be spectral singularities in energy bands
that produce anomalous effects and defectiveness. The quantum entanglement of a
generic non-Hermitian model with two different types of spectral exceptional
points (SEPs) is systematically investigated in this paper. We discovered a
relationship between non-unitary conformal field theories and the
-linear-type SEPs, which is typically associated with
-symmetry or pesdo-Hermicity spontaneous breaking. The underlying
association between -square-root-type SEPs, which arise concurrently with
real (imaginary) gap closing in the complex spectrum, mimicking
first-order-phase-transition criticalities, and complex conformal field
theories (cCFTs) is addressed through the calculation of complex central
charges. From the entanglement spectrum, zero-energy exceptional modes are
found to be distinct from normal zero modes or topological boundary modes.
Finally, we include a brief discussion of analogous non-Hermitian quantum spin
models and endeavor to establish an intuitive understanding of exceptional
points through the spin picture in various scenarios
A 1d lattice realization of chiral fermions with a non-Hermitian Hamiltonian
Quantum Hall state is characterized by a 2-dimensional(2D) bulk insulator and
a chiral fermion edge state, which gives quantized Hall conductance. It is
generally believed that the corresponding 1D chiral fermion state can not exist
by itself without its parent surface system. This is closely related to the
quantum anomaly of chiral fermion in quantum field theory. It has been
recognized that such an anomalous state implies the existence of a
topologically nontrivial bulk. Here we show that such a 1D chiral fermion state
can be realized without its corresponding surface system in a non-Hermitian
Hamiltonian. Our model possesses correct chiral anomaly and gravitational
anomaly, which ensures the quantization of the Hall conductance.Comment: 11 pages, 4 figure
Upregulation of Endogenous HMOX1 Expression by a Computer-Designed Artificial Transcription Factor
Heme oxygenase-1 (HO-1) is well known as a cytoprotective factor. Research has revealed that it is a promising therapeutic target for cardiovascular diseases. In the current study, an HMOX1 (HO-1 gene) enhancer-specific artificial zinc-finger protein (AZP) was designed using bioinformatical methods. Then, an artificial transcription factor (ATF) was constructed based on the AZP. In the ATF, the p65 functional domain was used as the effector domain (ED), and a nuclear localization sequence (NLS) was also included. We next analyzed the affinity of the ATF to the HMOX1 enhancer and the effect of the ATF on endogenous HMOX1 expression. The results suggest that the ATF could effectively upregulate endogenous HMOX1 expression in ECV304 cells. With further research, the ATF could be developed as a potential drug for cardiovascular diseases
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