617 research outputs found
Cosmologically safe QCD axion as a present from extra dimension
We propose a QCD axion model where the origin of PQ symmetry and suppression
of axion isocurvature perturbations are explained by introducing an extra
dimension. Each extra quark-antiquark pair lives on branes separately to
suppress PQ breaking operators. The size of the extra dimension changes after
inflation due to an interaction between inflaton and a bulk scalar field, which
implies that the PQ symmetry can be drastically broken during inflation to
suppress undesirable axion isocurvature fluctuations.Comment: 6 page
Diphoton Excess as a Hidden Monopole
We provide a theory with a monopole of a strongly-interacting hidden U(1)
gauge symmetry that can explain the 750-GeV diphoton excess reported by ATLAS
and CMS. The excess results from the resonance of monopole, which is produced
via gluon fusion and decays into two photons. In the low energy, there are only
mesons and a monopole in our model because any baryons cannot be gauge
invariant in terms of strongly interacting Abelian symmetry. This is
advantageous of our model because there is no unwanted relics around the BBN
epoch.Comment: 6 pages, 1 figur
Unification of the Standard Model and Dark Matter Sectors in [SU(5)U(1)]
A simple model of dark matter contains a light Dirac field charged under a
hidden U(1) gauge symmetry. When a chiral matter content in a strong dynamics
satisfies the t'Hooft anomaly matching condition, a massless baryon is a
natural candidate of the light Dirac field. One realization is the same matter
content as the standard SU(5)U(1) grand unified theory. We
propose a chiral [SU(5)U(1)] gauge theory as a unified model of the
SM and DM sectors. The low-energy dynamics, which was recently studied, is
governed by the hidden U(1) gauge interaction and the third-family
U(1) gauge interaction. This model can realize self-interacting
dark matter and alleviate the small-scale crisis of collisionless cold dark
matter in the cosmological structure formation. The model can also address the
semi-leptonic -decay anomaly reported by the LHCb experiment.Comment: 15 pages, 2 figure
Abundance of microRNA target motifs in the 3′-UTRs of 20527 human genes
AbstractA mechanism, selective avoidance, proposes that microRNA (miRNA) target sites are selectively depleted in the 3′-UTRs of genes expressed at the same time and place as a miRNA. If this mechanism is ubiquitous, the target motif occurrences in the 3′-UTRs would be decreased. To test this hypothesis, we examined miRNA target motif occurrences in the 3′- and 5′-UTRs of 20527 human protein-coding genes. The results revealed that miRNA target motifs appeared more frequently than non-target motifs and were enriched in the 3′-UTRs. This enrichment was relatively reduced in a set of 2525 genes coexpressed with miR-124a in the prefrontal cortex, but still remained at a high level, suggesting that miRNA target motifs are fostered by some other factors that surpass the influence of selective avoidance
Unification for the Darkly Charged Dark Matter
We provide a simple UV theory for a Dirac dark matter with a massless Abelian
gauge boson. We introduce a single fermion transforming as the
representation in the SO(10) gauge group, which is assumed to be
spontaneously broken to SU(5)U(1). The SU(5) gauge interaction
becomes strong at an intermediate scale and then we obtain a light composite
Dirac fermion with U(1) gauge interaction at the low-energy scale. Its
thermal relic can explain the observed amount of dark matter consistently with
other cosmological and astrophysical constraints. We discuss that a nonzero
kinetic mixing between the U(1) gauge boson and the Hypercharge gauge boson
is allowed and the temperature of the visible sector and the dark matter sector
can be equal to each other.Comment: 6 pages, 2 figure
Self-interacting dark matter with a vector mediator: kinetic mixing with U(1) gauge boson
A spontaneously broken hidden U(1) gauge symmetry can explain both the
dark matter stability and the observed relic abundance. In this framework, the
light gauge boson can mediate the strong dark matter self-interaction, which
addresses astrophysical observations that are hard to explain in collisionless
cold dark matter. Motivated by flavoured grand unified theories, we introduce
right-handed neutrinos and a flavoured gauge symmetry for the third
family U(1). The unwanted relic of the U(1) gauge boson decays
into neutrinos via the kinetic mixing with the U(1) gauge boson.
Indirect detection bounds on dark matter are systematically weakened, since
dark matter annihilation results in neutrinos. However, the kinetic mixing
between U(1) and U(1) gauge bosons are induced by quantum
corrections and leads to an observable signal in direct and indirect detection
experiments of dark matter. This model can also explain the baryon asymmetry of
the Universe via the thermal leptogenesis. In addition, we discuss the
possibility of explaining the lepton flavour universality violation in
semi-leptonic meson decays that is recently found in the LHCb experiment.Comment: 27 pages, 2 figures; v2: minor changes, Appendix A added, published
versio
Preventive Effect of Boiogito on Metabolic Disorders in the TSOD Mouse, a Model of Spontaneous Obese Type II Diabetes Mellitus
“Boiogito” is a Kampo preparation which has been used since ancient times in patients with obesity of the “asthenic constitution” type, so-called “watery obesity”, and its effect has been recognized clinically. In this study, we investigated the anti-obesity effect of Boiogito in the TSOD (Tsumura Suzuki Obese Diabetes) mouse, a model of spontaneous obese type II diabetes mellitus. Boiogito showed a significant anti-obesity effect in TSOD mice by suppressing body weight gain in a dosage-dependent manner. In addition, Boiogito showed significant ameliorative effects on features of metabolic syndrome such as hyperinsulinemia, fasting hyperglycemia and abnormal lipid metabolism. Regarding lipid accumulation in TSOD mice, Boiogito showed a significant suppressive effect on accumulation of subcutaneous fat, but the effect on the visceral fat accumulation that constitutes the basis of metabolic syndrome was weak, and the suppressive effect on insulin resistance was also weak. Furthermore, Boiogito did not alleviate the abnormal glucose tolerance, the hypertension or the peripheral neuropathy characteristically developed in the TSOD mice. In contrast, in the TSNO (Tsumura Suzuki Non-Obesity) mice used as controls, Boiogito suppressed body weight gain and accumulation of subcutaneous and visceral fat. The above results suggested that Boiogito is effective as an anti-obesity drug against obesity of the “asthenic constitution” type in which subcutaneous fat accumulates, but cannot be expected to exert a preventive effect against various symptoms of metabolic syndrome that are based on visceral fat accumulation
- …