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Shoseiryuto, a Japanese herbal medicine, is used to treat asthma exacerbation; however, the effect of Shoseiryutoin a clinical setting is yet to be elucidated. We aimed to examine the effect of Shoseiryutofor inpatients with asthma exacerbation and the reduction in the total amount of intravenous steroids administered during hospitalization, in-hospital mortality, and length of hospital stay using a national inpatient database in Japan.

The neutrino minimal standard model (νMSM) is the minimum extension of the standard model. In this model, the Dodelson-Widrow mechanism (DW) produces keV sterile neutrino dark matter (DM) and the degenerate GeV heavy Majorana neutrinos lead to leptogenesis. However, the DW mechanism has been ruled out by Lyman-a bounds and x-ray constraints. An alternative scenario that evades these constraints has been proposed, where the sterile neutrino DM is generated by the thermal freeze-in mechanism via a singlet scalar. In this paper, we consider a Higgs sector extension of the νMSM to improve dark matter sectors and leptogenesis scenarios, focusing on the thermal freeze-in production mechanism. We discuss various thermal freeze-in scenarios for the production of keV-MeV sterile neutrino DM with a singlet scalar, and reinvestigate the Lyman-a bounds and the x-ray constraints on the parameter regions. Furthermore, we propose thermal freeze-in leptogenesis scenarios in the extended νMSM. The singlet scalar needs to be TeV scale in order to generate the observed DM relic density and baryon number density with the thermal freeze-in production mechanism. [ABSTRACT FROM AUTHOR]

The semiclassical gravity describes gravitational backreactions of the classical spacetime interacting with quantum matter fields, but the quantum effects on the background are formally defined as higher-derivative curvatures. These induce catastrophic instabilities and classic solutions become unstable under small perturbations or their evolutions. In this paper, we discuss validity of the semiclassical gravity from the perspective of the spacetime instabilities and consider cosmological dynamics of the Universe in this theory. We clearly show that the homogenous and isotropic flat Universe is unstable and the solutions either grow exponentially or oscillate even in Planckian time tI=(α1GN)1/2≈α110-43sec. The subsequent curvature evolution leads to Planck-scale spacetime curvature in a short time and causes a catastrophe of the Universe unless one takes extremely large values of the gravitational couplings. Furthermore, we confirm the above suggestion by comparing the semiclassical solutions and ΛCDM with the Planck data and it is found that the semiclassical solutions are not consistent with the cosmological observations. Thus, the standard semiclassical gravity using quantum energy momentum tensor Tμν is not appropriate to describe our Universe. [ABSTRACT FROM AUTHOR]

In the present paper, we investigate regularization of the one-loop quantum corrections with infinite Kaluza-Klein (KK) states and evaluate Casimir vacuum energy from extra dimensions. The extradimensional models always involve the infinite massless or massive Kaluza-Klein states, and therefore, the regularization of the infinite KK corrections is highly problematic. In order to avoid the ambiguity, we adopt the proper time integrals and the Riemann zeta function regularization in evaluating the summations of infinite KK states. In the calculation, we utilize the KK regularization method with exchanging the infinite summations and the infinite loop integrals. At the same time, we also evaluate the correction by the dimensional regularization method without exchanging the summations and the loop integrals. Then, we clearly show that the regularized Casimir corrections from the KK states have the form of ∝1/R² for the Higgs mass and ∝1/R4 for the cosmological constant, where R is the compactification radius. We also evaluate the Casimir energy in supersymmetric extradimensional models. The contributions from bulk fermions and bulk bosons are not offset because we choose supersymmetry breaking boundary conditions. The nonzero supersymmetric Casimir corrections from extra dimensions undoubtedly contribute to the Higgs mass and the cosmological constant. We conclude that the coefficients of such corrections are enhanced compared to the case without bulk supersymmetry. [ABSTRACT FROM AUTHOR]

We study if eternal inflation is realized while satisfying the recently proposed string swampland criteria concerning the range of scalar field excursion, |Δϕ|c⋅V/MP, where D and c are constants of order unity and MP is the reduced Planck mass. We find that only the eternal inflation of chaotic type is possible for c∼O(0.01) and 1/D∼O(0.01) and that the Hubble parameter during the eternal inflation is parametrically close to the Planck scale and is in the range of 2πc≲Hinf/MP<1/√3. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the Higgs vacuum stability around evaporating black holes. We provide a new approach to investigate the false vacuum decay around the black hole and clearly show how vacuum fluctuations of the Higgs induce a gravitational collapse of the vacuum. Furthermore, we point out that the backreaction of the Hawking radiation cannot be ignored and the gravitational vacuum decay is exponentially suppressed. However, a large number of the evaporating (or evaporated) primordial black holes threaten the existence of the Universe and we obtain a new upper bound on the evaporating primordial black hole abundance from the vacuum stability. Finally, we show that the high-order corrections of the beyond standard model or quantum gravity would not destabilize the Higgs potential, otherwise even a single evaporating black hole triggers a collapse of the electroweak vacuum. [ABSTRACT FROM AUTHOR]

The cosmological Higgs vacuum stability has been an attractive research subject, and it is crucial to accurately follow the development of the Higgs fluctuations. In this work, we thoroughly investigate how the vacuum fluctuations of the Higgs field affect the stability of the electroweak vacuum in Friedmann-Lemaitre-Robertson-Walker (FLRW) background. Adopting adiabatic Wentzel-Kramers-Brillouin method approximation or adiabatic regularization methods, we clearly show that vacuum fluctuations of the Higgs field in the FLRW background depend on the curvature and also masses of the Higgs or other scalar fields. The Higgs fluctuations can generate true vacuum bubbles and trigger off a collapse of the electroweak vacuum. Furthermore we clearly show that the effective Higgs potential in the FLRW background is modified by the Higgs vacuum fluctuations. The vacuum fluctuations of the standard model fields can stabilize or destabilize the effective Higgs potential through backreaction effects. Considering the improved effective Higgs potential with the Higgs vacuum fluctuations 〈δϕ²〉 in various backgrounds, we provide new cosmological constraints on the mass of the Higgs-coupled scalar fields and a quantitative description of the Higgs stability in the FLRW background. [ABSTRACT FROM AUTHOR]

Current measurements of the Higgs boson mass and top Yukawa coupling suggest that the effective Higgs potential develops an instability below the Planck scale. If the energy scale of inflation is as high as the grand unified theory (GUT) scale, inflationary quantum fluctuations of the Higgs field can easily destabilize the standard electroweak vacuum and produce a lot of anti-de Sitter (AdS) domains. This destabilization during inflation can be avoided if a relatively large nonminimal Higgs-gravity or inflaton-Higgs coupling is introduced. Such couplings generate a large effective mass term for the Higgs, which can raise the effective Higgs potential and suppress the vacuum fluctuation of the Higgs field. After primordial inflation, however, such effective masses drops rapidly and the nonminimal Higgs-gravity or inflaton-Higgs coupling can cause large fluctuations of the Higgs field to be generated via parametric resonance, thus producing AdS domains in the preheating stage. Furthermore, thermal fluctuations of the Higgs field cannot be neglected in the proceeding reheating epoch. We discuss the Higgs vacuum fluctuations during inflation, preheating, and reheating, and show that the Higgs metastability problem is severe unless the energy scale of the inflaton potential is much lower than the GUT scale. [ABSTRACT FROM AUTHOR]