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Vasovagal syncope (VVS) or reflex is usually caused by physical and mental stress-related factors, like pain, anxiety, and fear, and it is one of the most frequent complications during dental treatment. Two patients, both with histories of dental phobia and of VVS during vaccination, venipuncture, and dental treatment with local anesthetics, were scheduled for dental treatment under intravenous (IV) sedation. However, both experienced episodes of VVS that occurred during venipuncture using a 24-gauge indwelling needle. We determined that pain was the main trigger of VVS for these patients and attempted to reduce venipuncture-associated pain using 60% lidocaine tape applied 3 hours before venipuncture at their next dental visits, respectively. Use of the lidocaine tape was successful and permitted comfortable placement of the IV catheter without any onset of VVS.

Bone conduction implants (BCIs) and middle ear implants (MEIs) are promising options for individuals with persistent chronic inflammation of the middle or outer ear. However, the structure of the middle ear is often altered in patients who undergo mastoidectomy or posterior wall removal for refractory otitis media, leaving uncertainty regarding the efficacy of hearing devices. Only a few studies have examined auditory outcomes based on the etiology of hearing impairment. We investigated hearing outcomes, including speech audiometry, in patients who underwent implantation after surgery for refractory otitis media. Our findings indicated that patients who received BCIs or MEIs achieved favorable hearing outcomes. Furthermore, a correlation was observed between the preoperative bone-conduction threshold at 1 kHz in the better ear and the sound-field threshold at 1 kHz with BCIs, whereas no correlation was observed between the preoperative bone-conduction threshold and the sound-field threshold with MEIs. This study highlights the positive impact of BCIs and MEIs in patients who undergo implantation after surgery for refractory otitis media. Additionally, our study identified parameters that predict postoperative efficacy.

Silver coating has an excellent antibacterial activity but low mechanical properties, e.g., microhardness. In order to improve simultaneously the antibacterial activity and surface hardness of titanium alloys, TiAlN/Ag multiple coatings with different gradient distributions in thickness were prepared on titanium alloys by unbalanced magnetron sputtering. The coatings with gradient thickened TiAlN–Ag cosputtered upper layers had a much stronger antibacterial activity, 99.82% in antiseptic Escherichia coli, than those with the gradient thinned upper layers. With increasing gradient cycles of the multiple coatings, the antibacterial activity decreased, whereas the hardness increased. The alternate growth of TiAlN and TiAlN–Ag layers may repeatedly provide an excellent comprehensive antibacterial activity (99.23% for Escherichia coli) and hardness (two times TC4 alloy) for a long term.

At present, the surface precision requirements for mold and die parts are extremely high. Especially in the precision mold and die cavity for ELD lenses, several mirror surfaces for automotive lens parts, and general camera lenses that required a few tens or a single nano-level like a mirror-finished surface. This final process is difficult to achieve with the conventional cutting edge of ball-nose end mills. In addition, it is commonly performing a very long time by manual polishing of the skilled worker after machining. To the problem, we purposed to develop a sintered polycrystalline diamond (PCD) rotary tool with a simple spherical cutting part. This PCD tool is a novel method for the final process of the small molds and dies cavities with high precision. A distinctive feature of its cutting can achieve a mirror-finished surface by full automation on a CNC machining center. This study aims to clarify the basic machining characteristics and verify its effectiveness on the hardened stainless steel commercial STAVAX with the hardness of 54 HRC for small mold and die cavities. As a result, we can clarify the chip generation mechanism, finish surface accuracy, internal crystal structure state, and residual stress characteristic of this processing method. It also shows that the manual problems related to mirror finishing of the precision mold and die cavity can be solved under the actual mold manufacturing process by consecutive conditions.

NiO combined with conductive materials is a practicable way to improve its catalytic property for the oxygen evolution reaction (OER) by enhancing its electrical conductivity. Herein, Ni@NiO@graphite nanoparticles less than 20 nm in average diameter were synthesized by a one-step chemical vapor deposition process. Due to the deliberately controlled lack of oxygen, Ni particles and carbon clusters decomposed from NiCp

Commercial CaF2 powder was applied to fabricate transparent CaF2 ceramics by spark plasma sintering under various sintering conditions. The low sintering temperatures and high pressures caused serious carbon contamination, while the soak time had less influence on the carbon concentration in the ceramics. The highest carbon contamination occurred to the CaF2 ceramics sintered at 800 °C. A low sintering pressure suppressed carbon contamination but led to high porosity and large pore size. A high pre-loading pressure led to relatively high porosity and carbon concentration. Furthermore, the relatively fast densification in the edge region of the plates may cause the non-uniform distribution of porosity, thereby affecting the distribution of carbon concentration. The low pre-loading pressure and the high sintering pressure reduced porosity and carbon concentration to obtain dense transparent ceramic with uniform microstructure and high transmittance.

Primary cystic duct carcinoma is a rare tumor. The curative treatment of cystic duct carcinoma is complete surgical resection, for which the evaluation of local extension is important. We herein report two cases of cystic duct carcinoma in which a preoperative examination was performed using per-oral cholangioscopy (POCS). Both patients underwent POCS due to suspicion of cystic duct carcinoma based on imaging findings. A visual analysis and biopsy were performed to evaluate local extension, which led to surgery. These cases suggest that POCS is useful for the preoperative assessment of local extension in advanced cystic duct carcinoma.

Quantitative

Recently, quantitative NMR (qNMR), especially 1H-qNMR, has been widely used to determine the absolute quantitative value of organic molecules. We previously reported an optimal and reproducible sample preparation method for 1H-qNMR. In the present study, we focused on a 31P-qNMR absolute determination method. An organophosphorus compound, cyclophosphamide hydrate (CP), listed in the Japanese Pharmacopeia 17th edition was selected as the target compound, and the 31P-qNMR and 1H-qNMR results were compared under three conditions with potassium dihydrogen phosphate (KH2PO4) or O-phosphorylethanolamine (PEA) as the reference standard for 31P-qNMR and sodium 4,4-dimethyl-4-silapentanesulfonate-d6 (DSS-d6) as the standard for 1H-qNMR. Condition 1: separate sample containing CP and KH2PO4 for 31P-qNMR or CP and DSS-d6 for 1H-qNMR. Condition 2: mixed sample containing CP, DSS-d6, and KH2PO4. Condition 3: mixed sample containing CP, DSS-d6, and PEA. As conditions 1 and 3 provided good results, validation studies at multiple laboratories were further conducted. The purities of CP determined under condition 1 by 1H-qNMR at 11 laboratories and 31P-qNMR at 10 laboratories were 99.76 ± 0.43 and 99.75 ± 0.53%, respectively, and those determined under condition 3 at five laboratories were 99.66 ± 0.08 and 99.61 ± 0.53%, respectively. These data suggested that the CP purities determined by 31P-qNMR are in good agreement with those determined by the established 1H-qNMR method. Since the 31P-qNMR signals are less complicated than the 1H-qNMR signals, 31P-qNMR would be useful for the absolute quantification of compounds that do not have a simple and separate 1H-qNMR signal, such as a singlet or doublet, although further investigation with other compounds is needed.

Spark plasma sintering (SPS) is a convenient approach for preparing transparent CaF2 ceramics. However, carbon contamination is a key issue that should be addressed to achieve high transparency. In this study, a commercially available CaF2 powder was preheated under vacuum before performing SPS to mitigate carbon contamination. During the preheating of the CaF2 powder, impurities adsorbed on the particle surface, such as H2O, CO2, and O2, are desorbed. Moreover, the interdiffusion of carbon contaminants is suppressed due to the pre-sintering of the raw powder. The in-line transmittance of the CaF2 ceramic prepared from the preheated powder increased to 85 % at the wavelength of 1100 nm, which is 38 % higher than that of the ceramic prepared without preheating. In addition, the in-line transmittance increased with increasing grain size of the ceramic, possibly because of the decrease in the number of scattering sources with the reduction in the grain boundary fraction.

A 72-year-old Japanese man with a 4-month history of hoarseness and 1-week history of difficulty breathing was admitted to our department. He underwent right total nephrectomy for primary clear cell-type renal cell carcinoma (RCC) 6 years ago and left partial nephrectomy for the metastasis 4 years ago. Flexible laryngeal fiberscope examination revealed bilateral subglottic stenosis without obvious mucosal lesions. Enhanced computerized tomography (CT) scan of the neck revealed that the cricoid cartilage had become bilaterally expansive and tumorous lesion exhibiting enhancement. We performed tracheostomy on the appointed day and biopsied the tumor in the cricoid cartilage via the skin incision. Results of histologic and immunohistologic examinations for AE1/AE3, CD10, and vimentin positivity were consistent with clear cell-type RCC. Chest and abdomen CT scans revealed a few tiny metastases in the upper lobe of the left lung but no recurrence in the abdomen. At 2 weeks from the day of tracheostomy, total laryngectomy was performed. Postoperatively, the patient was treated transorally with axitinib (10 mg/day) and as of 12 months he remains alive with unchanging lung metastasis. Next-generation sequencing of targeted regions using a surgical specimen from the tumor revealed a frameshift mutation in the von Hippel-Lindau gene (p.T124Hfs*35) and a missense mutation in the TP53 gene (p.H193R).

The exploration of cheap and efficient electrodes for hydrogen evolution reactions (HER) is extremely challenging. Herein, we report a newly-designed V2O3@Ni hybrid grown in situ on nickel foam as an efficient HER catalyst. The nickel foam not only promoted the electron transfer rate as a supporting substrate, but also worked as the source of Ni to enhance the integration of catalyst components with abundant active sites. Moreover, benefitting from the synergistic effect of the interface between V2O3 and Ni, which accelerated the entire electrochemical kinetics and facilitated the electron transfer, the in situ V2O3@Ni hybrid catalysts afforded a small overpotential of 47 mV and 100 mV at a current density of 10 mA cm−2 in 1.0 M KOH and 1.0 M PBS, respectively, and with excellent long-term stability. In addition, this research provides a new route for the fabrication of noble-metal-free electrocatalysts with excellent HER performance over a broad range of pH values.

Laser chemical vapor deposition (LCVD) was applied to prepare SmBa2Cu3O7-δ (SmBCO) superconductive films on single-crystalline LaAlO3 (100) substrates. The effect of oxygen partial pressure (PO2) on the crystal orientation, microstructure, and superconducting property of SmBCO film were investigated thoroughly. The results of X-ray diffraction (XRD) and Raman showed that the crystal orientation of SmBCO film was pure c-axis orientation at the PO2 of 200 Pa, and the a-axis orientation grains gradually emerged in SmBCO film with the increase of PO2. The deposition rate, critical temperature (Tc), critical current density (Jc) firstly increased and then decreased with the increase of PO2. At the PO2 of 200 Pa, the SmBCO film had smooth and dense surface, the lowest FWHM of φ-scan (1.1°), the highest Tc (89.2 K) and Jc (2.04 MA/cm2), which indicated that SmBCO superconductive films possessed excellent crystal structure and superconducting performance.

Cubic silicon carbide (3C–SiC) is an excellent protective film on graphite and has been fabricated via laser chemical vapor deposition (LCVD) with an extremely high deposition rate by our research group. To understand comprehensively its growth behavior, the polycrystalline 3C–SiC thick films with the preferred orientation of and were characterized by diverse measurements, especially electron back-scatter diffraction (EBSD). Along the growth direction of the -oriented 3C–SiC, the microstructure changed from equiaxed grains to elongated grains with orientation, and eventually the -oriented columnar grains. The stacking faults in the -oriented 3C–SiC could be marked as -oriented 6H–SiC. On the other hand, in the -oriented 3C–SiC films, the microstructure changed from mainly equiaxed grains to large columnar grains. The high-density stacking faults in -oriented 3C–SiC films may lead to the identification of the nominal 2H, 4H and 6H polytypes by Raman spectra and EBSD. The (0001) planes of 2H-, 4H–SiC are perpendicular to the growth direction, while that of 6H–SiC are parallel.