1,764 research outputs found
Leptophilic dark matter in gauged model in light of DAMPE cosmic ray excess
Motivated by the very recent cosmic-ray electron+positron excess observed by
DAMPE collaboration, we investigate a Dirac fermion dark matter (DM) in the
gauged model. DM interacts with the electron and muon via the
gauge boson . The model can explain the DAMPE data well.
Although a non-zero DM-nucleon cross section is only generated at one loop
level and there is a partial cancellation between and
couplings, we find that a large portion of mass is ruled out from
direct DM detection limit leaving the allowed mass to be close to two
times of the DM mass. Implications for and , and muon anomaly are also studied.Comment: Discussions added, version accepted by EPJ
Miniaturization of Branch-Line Coupler Using Composite Right/Left-Handed Transmission Lines with Novel Meander-shaped-slots CSSRR
A novel compact-size branch-line coupler using composite right/left-handed transmission lines is proposed in this paper. In order to obtain miniaturization, composite right/left-handed transmission lines with novel complementary split single ring resonators which are realized by loading a pair of meander-shaped-slots in the split of the ring are designed. This novel coupler occupies only 22.8% of the area of the conventional approach at 0.7 GHz. The proposed coupler can be implemented by using the standard printed-circuit-board etching processes without any implementation of lumped elements and via-holes, making it very useful for wireless communication systems. The agreement between measured and stimulated results validates the feasible configuration of the proposed coupler
Quantum correlation measure in arbitrary bipartite systems
A definition of quantum correlation is presented for an arbitrary bipartite
quantum state based on the skew information. This definition not only inherits
the good properties of skew information such as the contractivity and so on,
but also is effective and almost analytically calculated for any bipartite
quantum states. We also reveal the relation between our measure and quantum
metrology. As applications, we give the exact expressions of quantum
correlation for many states, which provides a direct support for our result.Comment: 6 pages, 2 figures. Comments are welcom
The Blood AFB1-DNA Adduct Acting as a Biomarker for Predicting the Risk and Prognosis of Primary Hepatocellular Carcinoma
Aflatoxin B1 (AFB1) is an important carcinogen for primary hepatocellular carcinoma (PHCC). However, the values of blood AFB1-DNA adducts predicting HCC risk and prognosis have not still been clear. We conducted a hospital-based case-control study, consisting of 380 patients with pathologically diagnosed PHCC and 588 controls without any evidence of liver diseases, to elucidate the associations between the amount of AFB1-DNA adducts in the peripheral blood and the risk and outcome of HCC. All subjects had not the history of hepatitis B and C virus infection. AFB1-DNA adducts were tested using enzyme-linked immunosorbent assay. Cases with PHCC featured an increasing blood amount of AFB1-DNA adducts compared with controls (2.01 ± 0.71 vs. 0.98 ± 0.63 μmol/DNA). Increasing adduct amount significantly grew the risk of PHCC [risk values, 1.82 (1.34–2.48) and 3.82 (2.71–5.40) for medium and high adduct level, respectively]. Furthermore, compared with patients with low adduct level, these with medium or high adduct level faced a higher death and tumor-recurrence risk. These results suggest that the blood AFB1-DNA adducts may act as a potential biomarker for predicting the risk and prognosis of PHCC
Demonstration of Einstein-Podolsky-Rosen Steering with Enhanced Subchannel Discrimination
Einstein-Podolsky-Rosen (EPR) steering describes a quantum nonlocal
phenomenon in which one party can nonlocally affect the other's state through
local measurements. It reveals an additional concept of quantum nonlocality,
which stands between quantum entanglement and Bell nonlocality. Recently, a
quantum information task named as subchannel discrimination (SD) provides a
necessary and sufficient characterization of EPR steering. The success
probability of SD using steerable states is higher than using any unsteerable
states, even when they are entangled. However, the detailed construction of
such subchannels and the experimental realization of the corresponding task are
still technologically challenging. In this work, we designed a feasible
collection of subchannels for a quantum channel and experimentally demonstrated
the corresponding SD task where the probabilities of correct discrimination are
clearly enhanced by exploiting steerable states. Our results provide a concrete
example to operationally demonstrate EPR steering and shine a new light on the
potential application of EPR steering.Comment: 16 pages, 8 figures, appendix include
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