156 research outputs found

    Higgs Alignment from Multicritical-Point Principle in Two Higgs Doublet Models

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    In models with non-minimal Higgs sectors, enforcing (near) Higgs alignment, necessary to prevent significant deviations in the Higgs boson coupling from the standard model prediction, causes a serious fine-tuning problem. We demonstrate that the Higgs alignment is naturally deduced from the multicritical point principle (MPP) in the general two Higgs doublet model. Furthermore, we discuss the possibility of realizing the Yukawa alignment from the MPP, which is necessary to prevent flavor-changing neutral currents mediated by Higgs bosons at tree level.Comment: 17 pages, 1 figur

    Quantum phase transition and absence of quadratic divergence in generalized quantum field theories

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    In ordinary thermodynamics, around first-order phase transitions, the intensive parameters such as temperature and pressure are automatically fixed to the phase transition point when one controls the extensive parameters such as total volume and total energy. From the microscopic point of view, the extensive parameters are more fundamental than the intensive parameters. Analogously, in conventional quantum field theory (QFT), coupling constants (including masses) in the path integral correspond to intensive parameters in the partition function of the canonical formulation. Therefore, it is natural to expect that in a more fundamental formulation of QFT, coupling constants are dynamically fixed a posteriori, just as the intensive parameter in the micro-canonical formulation. Here, we demonstrate that the automatic tuning of the coupling constants is realized at a quantum-phase-transition point at zero temperature, even when the transition is of higher order, due to the Lorentzian nature of the path integral. This naturally provides a basic foundation for the multi-critical point principle. As a concrete toy model for solving the Higgs hierarchy problem, we study how the mass parameter is fixed in the ϕ4\phi^4 theory at the one-loop level in the micro-canonical or further generalized formulation of QFT. We find that there are two critical points for the renormalized mass: zero and of the order of ultraviolet-cutoff. In the former, the Higgs mass is automatically tuned to be zero and thus its fine-tuning problem is solved. We also show that the quadratic divergence is absent in a more realistic two-scalar model that realizes the dimensional transmutation. Additionally, we explore the possibility of fixing quartic coupling in ϕ4\phi^4 theory and find that it can be fixed to a finite value.Comment: 29 pages, 3 figure

    Minimal scenario of Criticality for Electroweak scale, Neutrino Masses, Dark Matter, and Inflation

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    Yuta Hamada, Hikaru Kawai, Kiyoharu Kawana, Kin-ya Oda, Kei Yagyu. Minimal scenario of Criticality for Electroweak scale, Neutrino Masses, Dark Matter, and Inflation. https://arxiv.org/abs/2102.04617

    Minimal scenario of Criticality for Electroweak scale, Neutrino Masses, Dark Matter, and Inflation

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    We propose a minimal model that can explain the electroweak scale, neutrino masses, Dark Matter (DM), and successful inflation all at once based on the multicritical-point principle (MPP). The model has two singlet scalar fields that realize an analogue of the Coleman-Weinberg mechanism, in addition to the Standard Model with heavy Majorana right-handed neutrinos. By assuming a Z2Z_2 symmetry, one of the scalars becomes a DM candidate whose property is almost the same as the minimal Higgs-portal scalar DM. In this model, the MPP can naturally realize a saddle point in the Higgs potential at high energy scales. By the renormalization-group analysis, we study the critical Higgs inflation with non-minimal coupling ξH2R\xi |H|^2 R that utilizes the saddle point of the Higgs potential. We find that it is possible to realize successful inflation even for ξ=25\xi=25 and that the heaviest right-handed neutrino is predicted to have a mass around 101410^{14} GeV to meet the current cosmological observations. Such a small value of ξ\xi can be realized by the Higgs-portal coupling λSH0.32\lambda_{SH}\simeq 0.32 and the vacuum expectation value of the additional neutral scalar ϕ2.7\langle\phi\rangle\simeq 2.7 TeV, which correspond to the dark matter mass 2.0 TeV, its spin-independent cross section 1.8×1091.8\times10^{-9} pb, and the mass of additional neutral scalar 190 GeV.Comment: 28 pages, 6 figure

    Cyclic Regulation of T-Bet and GATA-3 in Human Endometrium

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    Endometrial cytokine expression is poorly understood. T-Bet and GATA-3 regulate cytokine expression in T-lymphocytes. Previous work has demonstrated expression of T-Bet in human endometrium. Changes in human endometrial T-Bet and GATA-3 mRNA and protein expression during the normal menstrual cycle were characterized. Human endometrium from each phase of the menstrual cycle underwent real-time reverse-transcriptase polymerase chain reaction and immunohistochemistry to examine expression and localization. T-Bet and GATA-3 mRNA were increased in the late secretory phase. Progesterone receptor (PR) mRNA was increased during the proliferative and early secretory phases. T-Bet and GATA-3 proteins localized cytoplasmically in the late secretory phase. PR protein displayed nuclear localization and maximal immunostaining during the early secretory phase. T-Bet and GATA-3 are expressed in endometrial epithelium cyclically during the menstrual cycle. T-Bet and GATA-3 are both upregulated during the late secretory phase and in the same cell types. The expression patterns of T-Bet and GATA-3 oppose PR, suggesting antagonistic function and/or regulation between PR and T-Bet/GATA-3

    Pulmonary alveolar proteinosis after lung transplantation: Two case reports and literature review

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    Pulmonary alveolar proteinosis (PAP) affecting transplanted lungs is not well recognized. Herein, we report two cases of PAP after lung transplantation (LTx). The first case was a 4-year-old boy with hereditary pulmonary fibrosis who underwent bilateral LTx and presented with respiratory distress on postoperative day (POD) 23. He was initially treated for acute rejection, died due to infection on POD 248, and was diagnosed with PAP at autopsy. The second case involved a 52-year-old man with idiopathic pulmonary fibrosis who underwent bilateral LTx. On POD 99, chest computed tomography revealed ground-glass opacities. Bronchoalveolar lavage and transbronchial biopsy led to a diagnosis of PAP. Follow-up with immunosuppression tapering resulted in clinical and radiological improvement. PAP after lung transplantation mimics common acute rejection; however, is potentially transient or resolved with tapering immunosuppression, as observed in the second case. Transplant physicians should be aware of this rare complication to avoid misconducting immunosuppressive management

    Xanthogranulomatous inflammation of the perimetrium with infiltration into the uterine myometrium in a postmenopausal woman: a case report

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    BACKGROUND: Xanthogranulomatous inflammation is an uncommon form of chronic inflammation that is destructive to the normal tissue of affected organs. Although xanthogranulomatous endometritis and xanthogranulomatous salpingitis of the female genital tract has been described previously, to the best of our knowledge, this is the first report of xanthogranulomatous inflammation with infiltration into the uterine myometrium from the perimetrium without endometritis. CASE PRESENTATION: A 68-year-old Japanese woman with intermittent lower abdominal pain and low-grade fever who was initially treated with antibiotics underwent hysterectomy due to abscess formation in the posterior wall of the myometrium and perimetrium (the outer serosal layer of the uterus). Histopathological findings revealed that the abscess was caused by xanthogranulomatous inflammation with the granulation tissue and chronic inflammatory cells that consisted of focal and sheets of foam cells. The inflammation destroyed the perimetrial elastic lamina, and the myometrium was deeply infiltrated by the xanthoma cells. Neither endometritis nor salpingitis was coexistent with the xanthogranulomatous inflammation. CONCLUSION: The patient was diagnosed as xanthogranulomatous inflammation, most likely arising from the perimetrium. Our findings suggest that the perimetrium, as well as the endometrium and adnexae, is one of the origins of xanthogranulomatous inflammation in female genital tract

    Vagus-macrophage-hepatocyte link promotes post-injury liver regeneration and whole-body survival through hepatic FoxM1 activation

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    The mechanisms underlying the regenerative capacity of the liver are not fully understood. Here, the authors show that the acute regenerative response to liver injury in mice is regulated by the communication involving the vagus nerve, macrophages, and hepatocytes, leading to hepatic FoxM1 activation and promotion of overall survival
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