Multiple-point principle with a scalar singlet extension of the Standard Model

We suggest a scalar singlet extension of the standard model, in which the multiple-point principle (MPP) condition of a vanishing Higgs potential at the Planck scale is realized. Although there have been lots of attempts to realize the MPP at the Planck scale, the realization with keeping naturalness is quite difficult. Our model can easily achieve the MPP at the Planck scale without large Higgs mass corrections. It is worth noting that the electroweak symmetry can be radiatively broken in our model. In the naturalness point of view, the singlet scalar mass should be of ${\cal O}(1)\,{\rm TeV}$ or less. We also consider right-handed neutrino extension of the model for neutrino mass generation. The model does not affect the MPP scenario, and might keep the naturalness with the new particle mass scale beyond TeV, thanks to accidental cancellation of Higgs mass corrections.Comment: 17 pages, 6 figures, version accepted for publication in PTE

Bosonic seesaw mechanism in a classically conformal extension of the Standard Model

We suggest the so-called bosonic seesaw mechanism in the context of a classically conformal $U(1)_{B-L}$ extension of the Standard Model with two Higgs doublet fields. The $U(1)_{B-L}$ symmetry is radiatively broken via the Coleman-Weinberg mechanism, which also generates the mass terms for the two Higgs doublets through quartic Higgs couplings. Their masses are all positive but, nevertheless, the electroweak symmetry breaking is realized by the bosonic seesaw mechanism. Analyzing the renormalization group evolutions for all model couplings, we find that a large hierarchy among the quartic Higgs couplings, which is crucial for the bosonic seesaw mechanism to work, is dramatically reduced toward high energies. Therefore, the bosonic seesaw is naturally realized with only a mild hierarchy, if some fundamental theory, which provides the origin of the classically conformal invariance, completes our model at some high energy, for example, the Planck scale. We identify the regions of model parameters which satisfy the perturbativity of the running couplings and the electroweak vacuum stability as well as the naturalness of the electroweak scale.Comment: 5 pages, 2 figures, published version in PL

Energetics and Electronic Structures of Inclusion Compounds of Large Fullerenes and Cycloparaphenylenes

The energetics and electronic structures of large fullerenes included within [n]cycloparaphenylenes ([n]CPPs) are investigated using density functional theory. We observe that the large fullerenes included within [n]CPP ([n]CPP ⊃ Cn, where n = 76 and 78) are energetically stable and the inclusion reactions are exothermic for the [n]CPP with a diameter of 1.49 nm or larger. Owing to the electronic states of the guest fullerene molecules and the host [n]CPP, [n]CPP ⊃ C60 possesses a staggered electronic structure near the energy gap between the highest occupied and lowest unoccupied states, leading to a narrower energy gap than that of fullerenes and CPP. We also demonstrate that the electron states associated with the fullerene exhibit an upward shift upon inclusion owing to the quantum confinement effect on the π states of fullerenes by the CPP

Energetics and electronic structures of perylene confined in carbon nanotubes

The energetics and geometries of perylene encapsulated in carbon nanotubes (CNTs) have been investigated employing density functional theory using the generalized gradient approximation combined with the van der Waals correction. Our calculations show that the encapsulated perylene molecules possess two metastable molecular conformations with respect to the CNT wall, which are almost degenerate with each other. A standing conformation, with respect to the CNT wall, is the ground state conformation for a semiconducting (19,0)CNT, while a lying conformation is the ground state for a metallic (11,11)CNT. Cooperation and competition between perylene–perylene and perylene–CNT interactions cause these possible perylene conformations inside CNTs. However, the electronic structure of the CNT encapsulating the perylene molecules is found to be insensitive to the molecular conformation

Block copolymer-mediated synthesis of gold nanoparticles in aqueous solutions: Segment effect on gold ion reduction, stabilization, and particle morphology

We report here on the segment effects of poly(ethylene oxide)-containing block copolymers (PEO-BCP) on the reduction activity for tetrachloride gold(III) ([AuCl4](-)), interfacial activity for gold surface, colloidal stability, and morphology of gold nanoparticles formed in aqueous solutions. In particular, the effects of poly(ethylene oxide) (PEO), poly(propylene oxide) (PPO), polyethylene (PE) segments and amino group (NH2) on the rate of [AuCl4](-) reduction, adsorption of PEO-BCP onto gold surface, colloidal stability, and morphology of gold nanoparticles formed in aqueous solutions were examined using a poly(ethylene oxide)-poly(propylene oxide) triblock copolymer (PEO-PPO-PEO, Pluronic L44), an amino-terminated poly(ethylene oxide)-poly(propylene oxide) block copolymer (PEO-PPO-NH2, SURFONAMINE(R) L-207), a poly(ethylene oxide) homopolymer (PEO, poly(ethylene glycol)2000), and a polyethylene-poly(ethylene oxide) block copolymer (PE-PEO). We found that the reduction activity of PEO-BCP for [AuCl4](-) became higher with the order of PEO-PPO-NH2 < PE-PEO < PEO < PEO-PPO-PEO. The interfacial activity (affinity) of PEO-BCP for gold surface increased with the order of PEO < PE-PEO < PEO-PPO-PEO < PEO-PPO-NH2. Consequently, the colloidal stability of gold nanoparticles formed in aqueous PEO-PPO-NH2 solutions was extremely high compared with that in PEO, PEO-PPO-PEO, and PE-PEO solutions. In addition, the size of gold nanoparticles formed in aqueous PEO-PPO-NH2 solutions was much smaller than that in aqueous solutions of PEO-PPO-PEO, PEO or PE-PEO.ArticleJOURNAL OF COLLOID AND INTERFACE SCIENCE. 394:124-131 (2013)journal articl

日本語Wikipediaを用いた慣用句の構成性の数値化

Kwansei Gakuin University会議名: 言語資源活用ワークショップ2018, 開催地: 国立国語研究所, 会期: 2018年9月4日-5日, 主催: 国立国語研究所 コーパス開発センター本研究は、日本語慣用句の構成性の度合いを数値化する手法を用いて、慣用句と一般連語句の差異について調査するものである。構成性の数値化は、日本語Wikipediaの全記事からなるコーパスをもとに、調査対象とするひとつの慣用句について構成的連語句分散表現ベクトルと非構成的連語句分散表現ベクトルの2つのベクトルをそれぞれ獲得し、この2つのベクトル間のコサイン類似度を計算することによって行う。構成的連語句分散表現ベクトルとは、連語句の構成要素である単語の分散表現ベクトルから加算的に計算されるベクトルである。一方、非構成的連語句分散表現ベクトルとは、連語句を内部構造のないひとまとまりの表現だと捉え、コーパスから直接的に獲得されるベクトルである。獲得した2つのベクトルのコサイン類似度が慣用句の構成性の度合いを反映するものであることを主張するため、一般連語句についても同じ手法により構成性の度合いの数値化を行い、慣用句について獲得された数値との間に統計的に有意な差が生じることを示す

Relationships between motivations to learn science and motivations for natural experience in junior high school students : An investigation using structural equation modeling

This study sought to investigate relationships between motivations to learn science and motivations for natural experience in junior high school students. The participants were 265 students in Kochi Prefecture, Japan. Firstly, explanatory factor analysis revealed that motivations for natural experience were composed of three factors: “familiarity with immediate natural environment”, “familiarity with animals through the senses”, and “interest in animal morphology and ecology”. Next, confirmatory factor analysis and structural equation modeling were used to further study the interrelationships. Motivations to learn science was assumed to include two factors: “expectancy of success” and “task values”. Excellent model fi t showed that factors in motivations to learn science have statistically significant effects on factors in motivations for natural experience.本研究の成果の一部は，平成27年度日本理科学会四国支部大会（高知大会）において岡田・草場・伊谷（2015）にて発表されたものである。また、本研究は平成27～31年度科学研究費補助金（基盤研究C：研究代表者：草場実）（課題番号15K04448，研究課題「メタ認知能力を基盤とした科学的思考力育成のための理科学習指導法の開発」）により行ったものである

Appropriate pelvic obliquity measurement method in Lenke type 5C adolescent idiopathic scoliosis: a preliminary study

Kanie Y., Takenaka S., Kitahara T., et al. Appropriate pelvic obliquity measurement method in Lenke type 5C adolescent idiopathic scoliosis: a preliminary study. Journal of Spine Surgery 10, 255 (2024); https://doi.org/10.21037/jss-23-138.Background: Although pelvic obliquity (PO) is a risk factor for postoperative coronal decompensation in corrective surgery in adolescent idiopathic scoliosis (AIS), especially Lenke 5C, methods of measuring PO are controversial. This study aimed to establish an appropriate measurement method using multiplanar reconstructed computed tomography (MPR-CT) images instead of standing posteroanterior (PA) whole-spine radiographs to evaluate PO in patients with Lenke 5C AIS. Methods: This study was a retrospective cross-sectional study. Twenty-five patients who underwent corrective surgery for AIS in Osaka University Hospital from August 2014 to February 2023 were included. Cobb angle, L5 tilt, C7 plumb line to center sacral vertebral line (C7PL-CSVL), and leg length discrepancy (LLD) were measured on standing PA whole-spine radiographs preoperatively. Sacral obliquity (SO), the slope of the upper endplate of S1, and iliac obliquity (IO), the tilt of the line connecting the iliac crests, were measured on standing PA whole-spine radiographs and MPR-CT (SO/IO-X-ray, SO/IO-CT, respectively). S1 angle and S2 angle were measured on CT. Results: The mean age of the patients was 18.7±3.9 years and all of them were females. SO-X-ray and SO-CT were larger than IO-X-ray and IO-CT, respectively. SO-X-ray was highly correlated with SO-CT (r=0.838, P<0.001). L5 tilt had higher correlation with SO-CT (r=0.884, P<0.001) than with SO-X-ray (r=0.726, P=0.001) and IO-CT (r=0.550, P=0.22). L5 tilt was correlated poorly with IO-X-ray (r=0.104, P=0.69). The S1 angle was 4.5±3.5° meanwhile the S2 angle was 1.2±2.1°, the sacral deformity was mainly due to the S1 vertebral wedging. Conclusions: Given the asymmetric sacral morphology, SO is more appropriate pelvic parameter than IO to represent the sacral tilt of Lenke 5C AIS, especially when measured using CT images to overcome the poor visibility on PA whole-spine radiographs

Molecular epidemiology of Clostridioides difficile and risk factors for the detection of toxin gene-positive strains

In this study, we investigated all Clostridioides difficile strains isolated from stool samples in Nagasaki University Hospital between January 2012 and December 2014. Toxin genes (tcdA, tcdB and cdtA/cdtB) were analyzed for multiplex PCR in a total of 213 strains. In the toxin gene-positive strain, PCR ribotyping was conducted using capillary gel electrophoresis-based PCR and the Webribo database. Patients’ backgrounds were analyzed by departments, disorders, antimicrobials, and clinical dates. The positive rates of tcdA, tcdB, and cdtA/cdtB genes were 62.9%, 63.4%, and 2.8%, respectively. The most frequent PCR ribotype was 047 (14.1%), followed by 014/0 (11.1%) and 002/0 (8.2%). In univariate analysis, the risk factors for the detection of toxin gene-positive strains in patients were older age (p = 0.0036), over ≥ 65 years old (p = 0.0175), the patients hospitalized at Department of Digestive Surgery (P = 0.0059), higher CRP level (P = 0.0395), and lower albumin level (p = 0.0014). In the multivariate analysis, the risk factor for detection of toxin gene-positive strains was the patients hospitalized at Department of Digestive Surgery (OR; 4.62, 95% CI; 1.18–18.0, p = 0.0274). In this study, the percentage of toxin gene-positive and cdtA/cdtB gene-positive strains was almost the same as that reported in previous studies, but the ribotype was different. In addition, we revealed that the risk factor associated with the detection of toxin gene-positive strains was the patients hospitalized at Department of digestive surgery