Asymmetric Mediator in Scotogenic Model

The scotogenic model is the Standard Model (SM) with Z_2 symmetry and the addition of Z_2 odd right-handed Majorana neutrinos and SU(2)_L doublet scalar fields. We have extended the original scotogenic model by an additional Z_2 odd singlet scalar field that plays a role in dark matter. In our model, the asymmetries of the lepton and Z_2 odd doublet scalar are simultaneously produced through CP-violating right-handed neutrino decays. While the former is converted into baryon asymmetry through the sphaleron process, the latter is relaid to the DM density through the decay of SU(2)_L doublet scalar that is named "asymmetric mediator". In this way, we provide an extended scotogenic model that predicts the energy densities of baryon and dark matter being in the same order of magnitude, and also explains the low-energy neutrino masses and mixing angles.Comment: 17 pages, 1 table, 5 figure

Effect of thyroid statuses on sodium/iodide symporter (NIS) gene expression in the extrathyroidal tissues in mice

<p>Abstract</p> <p>Background</p> <p>Iodide that is essential for thyroid hormone synthesis is actively transported into the thyroid follicular cells via sodium/iodide symporter (NIS) protein in vertebrates. It is well known that NIS expression in thyroid is regulated by the thyroid statuses mainly through thyroid stimulating hormone (TSH). Although <it>NIS </it>mRNA expressions in extrathyroidal tissues have been qualitatively reported, their regulation by thyroid statuses has not been well clarified.</p> <p>Methods</p> <p>Male ICR mice aged four weeks were assigned into three groups (control, hypothyroid, and hyperthyroid). Hypothyroid group of mice were treated with 0.02% methimazole in drinking water and hyperthyroid group of mice received intraperitoneal injection (4 μg _L-T₄twice a week) for four weeks. <it>NIS </it>mRNA expression levels in the tissues were evaluated using Northern blot hybridization and quantitative real-time RTPCR (qPCR). Additionally, end-point RTPCR for the thyroid follicular cell-characteristic genes (TSH receptor, <it>TSHR</it>; thyroid transcription factor-1, <it>TTF1</it>; and paired box gene 8, <it>Pax8</it>) was carried out.</p> <p>Results</p> <p>By Northern blot analysis, <it>NIS </it>mRNA was detected in thyroid and stomach. In addition to these organs, qPCR revealed the expression also in the submandibular gland, colon, testis, and lung. Expression of <it>NIS </it>mRNA in thyroid was significantly increased in hypothyroid and decreased in hyperthyroid group. Trends of <it>NIS </it>mRNA expression in extrathyroidal tissues were not in line with that in the thyroid gland in different thyroid statuses. Only in lung, <it>NIS </it>mRNA was regulated by thyroid statuses but in opposite way compared to the manner in the thyroid gland. There were no extrathyroidal tissues that expressed all three characteristic genes of thyroid follicular cells.</p> <p>Conclusions</p> <p><it>NIS </it>mRNA expression in the thyroid gland was up-regulated in hypothyroid mice and was down-regulated in hyperthyroid mice, suggesting that <it>NIS </it>mRNA in the thyroid gland is regulated by thyroid statuses. In contrast, <it>NIS </it>mRNA expression in extrathyroidal tissues was not altered by thyroid statuses although it was widely expressed. Lack of responsiveness of <it>NIS </it>mRNA expressions in extrathyroidal tissues reemphasizes additional functions of NIS protein in extrathyroidal tissues other than iodide trapping.</p

外側環軸関節の関節症性変化のリスク増加に関連する要因; 後ろ向き研究

Purpose Atlantodens osteoarthritis and atlantoaxial osteoarthritis cause neck pain and suboccipital headaches. Currently, knowledge on the risk factors for atlantoaxial osteoarthritis is lacking. This study aimed to investigate the factors related to the increased risk of atlantoaxial osteoarthritis. Methods We analyzed computed tomography (CT) images of the upper cervical spine of 1266 adult trauma patients for whom upper cervical spine CT was performed at our hospital between 2014 and 2019. The degree of atlantoaxial osteoarthritis was quantified as none-to-mild (not having osteoarthritis) or moderateto- severe (having osteoarthritis). Risk factors associated with atlantoaxial osteoarthritis were identified using univariate and multivariable logistic regression analyses. Results The study group included 69.4% men, and the overall average age of the study population was 54.9 ± 20.4 years. The following factors were independently and significantly associated with atlantoaxial osteoarthritis in the multivariable logistic regression analysis: age in the sixth decade or older (odds ratio [OR], 20.5; 95% confidence interval [CI], 6.2‒67.2, p < 0.001), having calcific synovitis (OR, 4.9; 95% CI, 2.4‒9.9, p < 0.001), women sex (OR, 3.3; 95% CI, 1.9‒5.7, p = 0.002), and not having atlantodens osteoarthritis (OR, 2.1; 95% CI, 1.2‒3.8, p = 0.014). Conclusion In the multivariable logistic regression analysis, age in the sixth decade or older, calcification of the transverse ligament, being women, and not having atlantodens osteoarthritis were found to be significantly associated with atlantoaxial osteoarthritis. Delayed diagnosis and treatment can be avoided by focusing on these risk factors.博士（医学）・甲第873号・令和5年3月15

Functional 1,3a,6a-triazapentalene scaffold : Design of fluorescent probes for kinesin spindle protein (KSP)

1,3a,6a-Triazapentalene is a compact fluorescent chromophore. In this study, triazapentalene was used to modify a series of biphenyl-type inhibitors of kinesin spindle protein (KSP) to develop fluorescent probes for the intracellular visualization of this protein. Microscopic studies demonstrated that these novel triazapentalene-labeled compounds exhibited inhibitory activity towards KSP in cultured cells and provided important information concerning the intracellular distribution

Establishing the carrier scattering phase diagram for ZrNiSn-based half-Heusler thermoelectric materials

Chemical doping is one of the most important strategies for tuning electrical properties of semiconductors, particularly thermoelectric materials. Generally, the main role of chemical doping lies in optimizing the carrier concentration, but there can potentially be other important effects. Here, we show that chemical doping plays multiple roles for both electron and phonon transport properties in half-Heusler thermoelectric materials. With ZrNiSn-based half-Heusler materials as an example, we use high-quality single and polycrystalline crystals, various probes, including electrical transport measurements, inelastic neutron scattering measurement, and first-principles calculations, to investigate the underlying electron-phonon interaction. We find that chemical doping brings strong screening effects to ionized impurities, grain boundary, and polar optical phonon scattering, but has negligible influence on lattice thermal conductivity. Furthermore, it is possible to establish a carrier scattering phase diagram, which can be used to select reasonable strategies for optimization of the thermoelectric performance.Comment: 21 pages, 5 figure

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

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

Laser-driven multi-MeV high-purity proton acceleration via anisotropic ambipolar expansion of micron-scale hydrogen clusters

強力なレーザーを使ってエネルギーがそろった純度100％の陽子ビーム発生に成功 --レーザー駆動陽子ビーム加速器の実現へ向けて大きく前進--. 京都大学プレスリリース. 2022-10-13.Multi-MeV high-purity proton acceleration by using a hydrogen cluster target irradiated with repetitive, relativistic intensity laser pulses has been demonstrated. Statistical analysis of hundreds of data sets highlights the existence of markedly high energy protons produced from the laser-irradiated clusters with micron-scale diameters. The spatial distribution of the accelerated protons is found to be anisotropic, where the higher energy protons are preferentially accelerated along the laser propagation direction due to the relativistic effect. These features are supported by three-dimensional (3D) particle-in-cell (PIC) simulations, which show that directional, higher energy protons are generated via the anisotropic ambipolar expansion of the micron-scale clusters. The number of protons accelerating along the laser propagation direction is found to be as high as 1.6 ±0.3 × 10⁹/MeV/sr/shot with an energy of 2.8 ±1.9 MeV, indicating that laser-driven proton acceleration using the micron-scale hydrogen clusters is promising as a compact, repetitive, multi-MeV high-purity proton source for various applications

Discriminative detection of laser-accelerated multi-MeV carbon ions utilizing solid state nuclear track detectors

A new diagnosis method for the discriminative detection of laser‐accelerated multi‐MeV carbon ions from background oxygen ions utilizing solid‐state nuclear track detectors (SSNTDs) is proposed. The idea is to combine two kinds of SSNTDs having different track registration sensitivities: Bisphenol A polycarbonate detects carbon and the heavier ions, and polyethylene terephthalate detects oxygen and the heavier ions. The method is calibrated with mono‐energetic carbon and oxygen ion beams from the heavy ion accelerator. Based on the calibration data, the method is applied to identify carbon ions accelerated from multilayered graphene targets irradiated by a high‐power laser, where the generation of high‐energy high‐purity carbon ions is expected. It is found that 93 ± 1% of the accelerated heavy ions with energies larger than 14 MeV are carbons. The results thus obtained support that carbon‐rich heavy ion acceleration is achieved