18,732 research outputs found
Possible Exotic State
We study the possible exotic states with using the
tetraquark interpolating currents with the QCD sum rule approach. The extracted
masses are around 4.85 GeV for the charmonium-like states and 11.25 GeV for the
bottomomium-like states. There is no working region for the light tetraquark
currents, which implies the light state may not exist below 2 GeV.Comment: 13 pages, 11 figures, 2 table
Study on the mechanism of open-flavor strong decays
The open-flavor strong decays are studied based on the interaction of
potential quark model. The decay process is related to the s-channel
contribution of the same scalar confinment and one-gluon-exchange(OGE)
interaction in the quark model. After we adopt the prescription of massive
gluons in time-like region from the lattice calculation, the approximation of
four-fermion interaction is applied. The numerical calculation is performed to
the meson decays in , , light flavor sector. The analysis of the
ratios of and show
that the scalar interaction should be dominant in the open-flavor decays
On determination of the geometric cosmological constant from the OPERA experiment of superluminal neutrinos
The recent OPERA experiment of superluminal neutrinos has deep consequences
in cosmology. In cosmology a fundamental constant is the cosmological constant.
From observations one can estimate the effective cosmological constant
which is the sum of the quantum zero point energy
and the geometric cosmological constant . The
OPERA experiment can be applied to determine the geometric cosmological
constant . It is the first time to distinguish the contributions of
and from each other by experiment. The
determination is based on an explanation of the OPERA experiment in the
framework of Special Relativity with de Sitter space-time symmetry.Comment: 7 pages, no figure
Electrical coupling between ventricular myocytes and myofibroblasts in the infarcted mouse heart
Aims:
Recent studies have demonstrated electrotonic coupling between scar tissue and the surrounding myocardium in cryoinjured hearts. However, the electrical dynamics occurring at the myocyte-nonmyocyte interface in the fibrotic heart remain undefined. Here, we sought to develop an assay to interrogate the nonmyocyte cell type contributing to heterocellular coupling and to characterize, on a cellular scale, its voltage response in the infarct border zone of living hearts.
Methods and results:
We used two-photon laser scanning microscopy in conjunction with a voltage-sensitive dye to record transmembrane voltage changes simultaneously from cardiomyocytes and adjoined nonmyocytes in Langendorff-perfused mouse hearts with healing myocardial infarction. Transgenic mice with cardiomyocyte-restricted expression of a green fluorescent reporter protein underwent permanent coronary artery ligation and their hearts were subjected to voltage imaging 7-10 days later. Reporter-negative cells, i.e. nonmyocytes, in the infarct border zone exhibited depolarizing transients at a 1:1 coupling ratio with action potentials recorded simultaneously from adjacent, reporter-positive ventricular myocytes. The electrotonic responses in the nonmyocytes exhibited slower rates of de- and repolarization compared to the action potential waveform of juxtaposed myocytes. Voltage imaging in infarcted hearts expressing a fluorescent reporter specifically in myofibroblasts revealed that the latter were electrically coupled to border zone myocytes. Their voltage transient properties were indistinguishable from those of nonmyocytes in hearts with cardiomyocyte-restricted reporter expression. The density of connexin43 expression at myofibroblast-cardiomyocyte junctions was ∼5% of that in the intercalated disc regions of paired ventricular myocytes in the remote, uninjured myocardium, whereas the ratio of connexin45 to connexin43 expression levels at heterocellular contacts was ∼1%.
Conclusion:
Myofibroblasts contribute to the population of electrically coupled nonmyocytes in the infarct border zone. The slower kinetics of myofibroblast voltage responses may reflect low electrical conductivity across heterocellular junctions, in accordance with the paucity of connexin expression at myofibroblast-cardiomyocyte contacts
Photon Conversion and Radiation Synergism in Eu/Tb Complexes Incorporated Poly Methyl Methacrylate
Green and red emissions in terbium and europium benzoic acids (TBA and EBA) incorporated poly methyl methacrylates (PMMA) are exhibited. Larger intensity parameters Ω2 (11.13×10-20 cm2) and Ω4 (13.15×10-20 cm2) of Eu3+ indicate a high inversion asymmetrical and strong covalent environment around lanthanide (Ln) ions and maximum emission cross section σem-max (2.45×10-21 cm2) for the dominant transition D50→F27 of Eu3+ reveals the effective photon conversion capacity in EBA incorporated PMMA. Color variation and fluorescence enhancement are validated to be originated from energy transfer and synergistic effect in TBA/EBA coincorporated PMMA system. The results indicate that Eu and Tb complexes incorporated PMMA with effective photon conversion hold great prospect in increment of lighting quality and enhancement of solar-cell efficiency employed in outer space
Universality of preference behaviors in online music-listener bipartite networks: A Big Data analysis
We investigate the formation of musical preferences of millions of users of
the NetEase Cloud Music (NCM), one of the largest online music platforms in
China. We combine the methods from complex networks theory and information
sciences within the context of Big Data analysis to unveil statistical patterns
and community structures underlying the formation and evolution of musical
preference behaviors. Our analyses address the decay patterns of music
influence, users' sensitivity to music, age and gender differences, and their
relationship to regional economic indicators. Employing community detection in
user-music bipartite networks, we identified eight major cultural communities
in the population of NCM users. Female users exhibited higher within-group
variability in preference behavior than males, with a major transition
occurring around the age of 25. Moreveor, the musical tastes and the preference
diversity measures of women were also more strongly associated with economic
factors. However, in spite of the highly variable popularity of music tracks
and the identified cultural and demographic differences, we observed that the
evolution of musical preferences over time followed a power-law-like decaying
function, and that NCM listeners showed the highest sensitivity to music
released in their adolescence, peaking at the age of 13. Our findings suggest
the existence of universal properties in the formation of musical tastes but
also their culture-specific relationship to demographic factors, with
wide-ranging implications for community detection and recommendation system
design in online music platforms.Comment: 23 pages, 15 Figures, 4 Table
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