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Introduction: Postoperative dysphonia is mostly caused by vocal fold scarring, and careful management of vocal fold surgery has been reported to reduce the risk of scar formation. However, depending on the vocal fold injury, treatment of postoperative dysphonia can be challenging. Objective: The goal of the current study was to develop a novel prophylactic regenerative approach for the treatment of injured vocal folds after surgery, using biodegradable gelatin hydrogel microspheres as a drug delivery system for basic fibroblast growth factor. Methods: Videoendoscopic laryngeal surgery was performed to create vocal fold injury in 14 rabbits. Immediately following this procedure, biodegradable gelatin hydrogel microspheres with basic fibroblast growth factor were injected in the vocal fold. Two weeks after injection, larynges were excised for evaluation of vocal fold histology and mucosal movement. Results: The presence of poor vibratory function was confirmed in the injured vocal folds. Histology and digital image analysis demonstrated that the injured vocal folds injected with gelatin hydrogel microspheres with basic fibroblast growth factor showed less scar formation, compared to the injured vocal folds injected with gelatin hydrogel microspheres only, or those without any injection. Conclusion: A prophylactic injection of basic fibroblast growth factor -containing biodegradable gelatin hydrogel microspheres demonstrates a regenerative potential for injured vocal folds in a rabbit model.

Abstract We report a rare case of angiomyolipoma (AML) of the larynx. AML belongs to the family of perivascular epithelioid cell tumors (PEComas). We review the literature on PEComas and describe differences in immunohistochemical findings between renal AML and AML in the head and neck region.

Purpose - The purpose of this paper is to discuss the development and assessment of learning support environments for academic writing that utilize ICT, such as e-learning and online tutoring, in Japanese higher education. First, the authors introduce the design of an e-learning writing program for the Japanese language and assess whether the program is an effective learning support tool for undergraduates. Second, the authors analyze and assess online tutoring support for academic writing and clarify the merits and disadvantages of online and offline tutoring at writing centers, then suggest instructional strategies by analyzing the writing tutoring process. Design/methodology/approach - The authors adopted e-learning goals to assess its effectiveness. The authors asked the participants questions they could answer from five-point scales, conducted a paired t-test, and included a free description-type questionnaire. Then, to assess online tutoring, the 12 students took pre- and post-test questionnaires, after which the authors conducted a Wilcoxon signed rank test. In addition, the authors carried out a Kruskal–Wallis rank sum test in order to confirm differences in satisfaction level and the effectiveness of face-to-face tutoring and online tutoring. Findings - By analyzing the pre- and post-test results, the t-test confirmed that the students found the e-learning system to be effective for nurturing academic literacy. This means the system is appropriate as a support tool for nurturing academic writing, especially writing knowledge and rules, and university must provide a comprehensive learning support environment including e-learning. Next, the authors found no statistically significant difference between face-to-face and online tutoring, although some problems with the writing process remained. So online tutoring has opportunity to promote autonomous learning. The research results make it clear that because of writing centers’ potential and their effectiveness in utilizing ICT tools. Originality/value - Research findings about academic writing are to improve the tutoring process and writing strategies, such as the use of ICT for academic writing support like e-learning, online tutoring, do not exist. To provide learning opportunity to learners and promote autonomous learning, e-learning and online tutoring are important. For the reasons noted above, it is necessary to provide an alternative writing support environment to students in Japan. Therefore, the authors report on and assess the development of learning support environments for e-learning programs and online tutoring for academic writing at the undergraduate level in Japan.

Objectives: The mean bilateral nasal resistance in normal Japanese adults is 0.25±0.12 Pa/cm3/s, but this value in children remains unknown. This study aimed to determine the mean nasal resistance values in Japanese children. Methods: We measured nasal resistance in a normal rhinosinal status and rhinosinal morbidity in elementary school children by active anterior rhinomanometry. We used a nasal nozzle that has been recommended for the standard measurement of nasal resistance by the Japanese Standardization Committee on Rhinomanometry. Results: The mean value of bilateral nasal resistance at ΔP 100 Pa in 1204 normal children was 0.35±0.13 Pa/cm3/s on inspiration and 0.37±0.14 Pa/cm3/s on expiration (ΔP is an abbreviation for the pressure gradient). Nasal resistance in children decreased with growth, making it difficult to determine a single value of nasal resistance in normal children. The mean value of bilateral nasal resistance at ΔP 100 Pa in 838 children with nasal problems, including marked adenoidal hypertrophy, was 0.56±0.87 Pa/cm3/s on inspiration and 0.55±0.47 Pa/cm3/s on expiration. Conclusions: Bilateral nasal resistance is significantly greater in children with nasal morbidity than in normal children. Additionally, nasal resistance in normal children is best assessed according to the body height category.

We study orbital diamagnetism at zero temperature in (2 + 1)-dimensional Dirac fermions with a short-range interaction which exhibits a quantum phase transition to a charge density wave (CDW) phase. We introduce orbital magnetic fields into spinless Dirac fermions on the π -flux square lattice, and analyze them by using infinite density matrix renormalization group. It is found that the diamagnetism remains intact in the Dirac semimetal regime, while it is monotonically suppressed in the CDW regime. Around the quantum critical point of the CDW phase transition, we find a scaling behavior of the diamagnetism characteristic of the chiral Ising universality class. Besides, the scaling analysis implies that the robust orbital diamagnetism at weak magnetic fields in a Dirac semimetal regime would hold not only in our model but also in other interacting Dirac fermion systems as long as scaling regions are wide enough. The scaling behavior may also be regarded as a quantum, magnetic analogue of the critical Casimir effect which has been widely studied for classical phase transitions.

We present a theory of a hybrid quantum liquid state, the quantum spin-dipole liquid (QSDL), in a hydrogen-bonded electron system, by combining a quantum proton ice and Anderson's resonating valence bond spin liquid theory, motivated by the recent experimental discovery of a quantum spin liquid with proton fluctuations in κ-H_{3}(Cat-EDT-TTF)_{2} (a.k.a. H-Cat). In our theory, an electron spin liquid and a proton dipole liquid are realized simultaneously in the ground state called quantum valence bond ice. In this state, neither of them can be established independently of the other. Analytical and numerical calculations reveal that this state has a large entanglement entropy between spins and dipoles, which is far beyond the (crude) Born-Oppenheimer approximation. We also examine the stability of QSDL with respect to perturbations and discuss implications for experiments in H-Cat and its deuterated analog D-Cat.

We study quantum criticality of the magnetic-field-induced charge density wave (CDW) order in correlated spinless Dirac fermions on the π-flux square lattice at zero temperature as a prototypical example of the magnetic catalysis, by using the infinite density matrix renormalization group. It is found that the CDW order parameter M(B) exhibits an anomalous magnetic field (B) scaling behavior characteristic of the (2+1)-dimensional chiral Ising universality class near the quantum critical point, which leads to a strong enhancement of M(B) compared with a mean-field result. We also establish a global phase diagram in the interaction-magnetic field plane for the fermionic quantum criticality.

Motivated by the recent experimental observations of quantum oscillations in the Kondo insulators SmB_{6} and YbB_{12}, we study magneto-optical conductivity of Kondo insulators. We show that there exist nontrivial cyclotron resonance peaks in a frequency domain below the hybridization gap as a result of the characteristic Landau level structure of the system. Furthermore, these low-energy peaks are enhanced near the insulator-metal phase transition driven by an applied magnetic field and stable even at low temperatures. They are smoothly connected via the Kondo effect to resonance peaks for unhybridized conduction and f electrons at high temperature. The nontrivial cyclotron resonance is a dynamical counterpart of quantum oscillations in static quantities, and through this intimate connection it will provide a useful insight for the latter.

Cylindrical vector beam (CVB) is a structured lightwave characterized by its topologically nontrivial nature of the optical polarization. The unique electromagnetic field configuration of CVBs has been exploited to optical tweezers, laser accelerations, and so on. However, use of CVBs in research fields outside optics such as condensed matter physics has not progressed. In this paper, we propose potential applications of CVBs to those fields based on a general argument on their absorption by matter. We show that pulse azimuthal CVBs around terahertz or far-infrared frequencies can be a unique and powerful mean for time-resolved spectroscopy of magnetic properties of matter and claim that an azimuthal electric field of a pulse CVB would be a novel way of studying and controlling edge currents in topological materials. We also demonstrate how powerful CVBs will be as a tool for Floquet engineering of nonequilibrium states of matter.