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Abstract Background The COVID-19 pandemic led to concerns about the potential airborne transmission of the virus during dental procedures, but evidence of actual transmission in clinical settings was lacking. This study aimed to observe the behavior of dental sprays generated from dental rotary handpieces and to evaluate the effectiveness of high-volume evacuators (HVEs) using laser light sheets and water-sensitive papers. Methods A dental manikin and jaw model were mounted in a dental treatment unit. Mock cutting procedures were performed on an artificial tooth on the maxillary left central incisor using an air turbine, a contra-angle electric micromotor (EM), and a 1:5 speed-up contra-angle EM (×5EM). Intraoral vacuum and extraoral vacuum (EOV) were used to verify the effectiveness of the HVEs. The dynamics and dispersal range of the dental sprays were visualized using a laser light sheet. In addition, environmental surface pollution was monitored three-dimensionally using water-sensitive papers. Results Although the HVEs were effective in both the tests, the use of EOV alone increased vertical dispersal and pollution. Conclusions The use of various types of HVEs to reduce the exposure of operators and assistants to dental sprays when using dental rotary cutting instruments is beneficial. The study findings will be helpful in the event of a future pandemic caused by an emerging or re-emerging infectious disease.

A single crystalline thin film of Ba _2 Ti _6 O _13 was grown on the (210) surface of a SrTiO _3 single-crystal substrate by pulsed laser deposition. Scanning transmission electron microscopy shows that the Ba _2 Ti _6 O _13 thin film grew epitaxially with the a -plane, and the b -/ c -axes of Ba _2 Ti _6 O _13 parallel to the (210) plane and the [00 $\bar{1}$ ]/[ $\bar{1}$ 20] directions of SrTiO _3 , respectively. The electrical conductance of the Ba _2 Ti _6 O _13 film was approximately one order larger than that of the reduced SrTiO _3− _δ single crystal with oxygen deficiency of roughly δ = 0.05. Electronic structure calculations predict that Ba _2 Ti _6 O _13 is an n-type degenerate semiconductor with spin-split states primarily of Ti 3d orbital.

Abstract Crystal-grain refinement is one of the effective approaches to obtaining high-strength materials. A good strength/ductility balance has been reported in fine grains of high- and medium-entropy alloys. However, crystal-grain refinement at the nanometer scale has not been achieved yet. In this study, we used electrodeposition to fabricate 0.2-mm thick equiatomic FeCoNi medium-entropy alloys (MEAs) with 10-nm crystal grains. The nanocrystalline FeCoNi MEAs exhibit the maximum tensile strength of 1.6 GPa, which is the highest reported result to date.

Background: Eosinophilic chronic rhinosinusitis (ECRS) is a subtype of chronic rhinosinusitis with nasal polyps in Japanese. ECRS highly associated with asthma is a refractory eosinophilic airway inflammation and requires comprehensive care as part of the united airway concept. We recently reported a series of ECRS patients with asthma treated with fine-particle inhaled corticosteroid (ICS) exhalation through the nose (ETN).Objective: To evaluate fine-particle ICS ETN treatment as a potential therapeutic option in ECRS with asthma.Methods: Twenty-three patients with severe ECRS under refractory to intranasal corticosteroid treatment were randomized in a double-blind fashion to receive either HFA-134a-beclomethasone dipropionate (HFA-BDP) metered-dose inhaler (MDI) ETN (n = 11) or placebo MDI ETN (n = 12) for 4 weeks. Changes in nasal polyp score, computed tomographic (CT) score, smell test, and quality of life (QOL) score from baseline were assessed. Fractionated exhaled nitric oxide (FENO) was measured as a marker of eosinophilic airway inflammation. Response to corticosteroids was evaluated before and after treatment. Additionally, deposition of fine-particles was visualized using a particle deposition model. To examine the role of eosinophils on airway inflammation, BEAS-2B human bronchial epithelial cells were co-incubated with purified eosinophils to determine corticosteroid sensitivity.Results: HFA-BDP MDI ETN treatment improved all assessed clinical endpoints and corticosteroid sensitivity without any deterioration in pulmonary function. FENO and blood eosinophil number were reduced by HFA-BDP MDI ETN treatment. The visualization study suggested that ETN at expiratory flow rates of 10–30 L/min led to fine particle deposition in the middle meatus, including the sinus ostia. Co-incubation of eosinophils with BEAS-2B cells induced corticosteroid resistance.Conclusions: Additional HFA-BDP MDI ETN treatment was beneficial in patients with ECRS and should be considered as a potential therapeutic option for eosinophilic airway inflammation such as ECRS with asthma. (UMIN-CTR: R000019325) (http://www.umin.ac.jp/ctr/index.htm).

Nanoscale designs are known to increase the energy conversion efficiency of photoelectrochemical water splitting. Here, the authors report a self-organized nanocomposite formed by embedding self-assembled metal nanopillars in a semiconductor thin film, for enhanced photocarrier separation efficiency.

The use of inverse magnetostriction effect is a possible approach for the applications of actuator, sensor and energy harvester. A strong textured Fe100-xCox (x = 70 mol%) magnetostrictive alloys have been studies as a new smart material. The design of microstructure plays important roles in performance enhancement of power generation by heat-treatment at several temperatures from 420℃ to 850℃. Experimentally, the effect of heat-treatment on their microstructures was evaluated by laser microscope and X-ray diffraction and orientation analysis. Furthermore, the magnetic, magnetostrictive and electric power generation characteristics were investigated by vibrating sample magnetometer (VSM), single-axis strain gauge and drop impact test, respectively. These results indicated the lattice strain in the crystal grain was related to the coercivity resulting from the domain wall mobility in the materials. Moreover, the orientation aligned by the drawing process was related to the magnetostriction. Also, the large grain width, that is, low grain boundary density was strongly attributed to enhance the magnetostrictive susceptibility. The output power calculated from the output waveform was reached up to 91 mJ/s for 820℃-WQ (water quenching) resulting from the high magnetostrictive susceptibility as well as the quenching effect from the temperature near the (bcc + fcc)/bcc interface. These results indicated that it is important to control not only the annealing conditions for improving magnetostrictive susceptibility but also the control of residual stress or grain boundary density for developing higher performance of output characteristics.

In a previous case report, we determined for the first time that uvulopalatopharyngoplasty (UPPP) does not change the volume of the upper airway but causes morphological changes in the entire upper airway. The objective of this study is to elucidate the mechanisms underlying the improvement in obstructive sleep apnea syndrome (OSAS) by UPPP. We present an additional case involving a patient with OSAS treated using UPPP. Morphological and numerical parameter changes after surgery were compared with the corresponding preoperative values. Anatomically accurate upper airway computational models were reconstructed from computed tomographic imaging data. In addition, computed fluid dynamics analysis was performed to reveal inhalation flow characteristics before and after UPPP and clearly assess the effect of UPPP on airflow patterns in the patient’s upper airway. An important benefit of UPPP is the morphological changes in the entire upper airway, in addition to widening the restricted area. These morphological changes induce laminarization of the pharyngeal jet. To obtain sufficient efficacy of UPPP in OSAS, the morphological changes in the upper airway and the airflow pattern after the surgery must be controlled.

Objective. The aim of this study was to investigate the changes in velopharyngeal and glossopharyngeal airway morphology and volume after uvulopalatopharyngoplasty in three adult obstructive sleep apnea syndrome patients who had bilateral large tonsils using three-dimensional computed tomography. Case Report. All three patients (one male and two females) who presented with a history of heavy snoring and excessive daytime sleepiness were examined with overnight nocturnal polysomnography, which indicated moderate-to-severe obstructive sleep apnea syndrome. Because all patients had large tonsils, uvulopalatopharyngoplasty was expected to enlarge the pharyngeal airway. Polysomnography and three-dimensional computed tomography scanning were performed and compared, both before and 3 months after uvulopalatopharyngoplasty. Results. Unexpectedly, although the morphology of the glossopharyngeal airway clearly changed after UPPP, the volume changes in the velopharyngeal and glossopharyngeal airways were negligible.

Malignant transformation of endometriosis has been extensively described in the literature. However, extragonadal endometrioid adenocarcinoma, either de novo or arising from malignant transformation of endometriosis, is rare. The present case report describes a patient with endometrioid adenocarcinoma on the serous surface of the small intestine. A 25- year-old female with no history of endometriosis was referred to our hospital with an intrapelvic tumor. An internal examination, ultrasound, and magnetic resonance imaging revealed a round mass approximately 80 mm in diameter; however, identification of the affected organ was difficult. Because we could not rule out malignancy based on the non-specific radiologic findings, laparotomy was performed. A mass with ileal adhesions was detected intraoperatively. In addition, the uterus and bilateral adnexa appeared normal. The tumor was resected with part of the ileum. Histopathology confirmed a diagnosis of endometrioid adenocarcinoma originating from the serous surface of the small intestine.

We first successfully synthesized Li1+x−yNb1−x−3yTix+4yO3 (LNT) solid solutions (0.13 ≤ x ≤ 0.18, 0 ≤ y ≤ 0.06) rapidly at 1373 K for one hour under 0.35 MPa by the controlling of air pressure using an air-pressure control atmosphere furnace. The composition is a formation area of a superstructure for LNT, in which the periodical intergrowth layer was formed in the matrix, and where it can be controlled by Ti content. Therefore, the sintering time depended on Ti content, and annealing was repeated for over 24 h until a homogeneous structure was formed using a conventional electric furnace. We clarified the mechanism of the rapid sintering using various microscale to nanoscale characterization techniques: X-ray diffraction, a scanning electron microscope, a transmission electron microscope (TEM), a Cs-corrected scanning TEM equipped with electron energy-loss spectroscopy, and X-ray absorption fine structure spectroscopy.

The apparent activation energy of sintering for 8-mol%-Y2O3-doped ZrO2 during shrinkage-rate-controlled flash sintering was determined using a master sintering curve. The activation energy during SCF sintering was found to decrease from approximately 700 to 430 kJ/mol with density. The activation energy in a high-density region is approximately similar value of lattice diffusion, 460 kJ/mol. The relative density range over which the decrease in activation energy occurred during SCF sintering was smaller than during thermal sintering and further moved to a lower temperature range. The increase in shrinkage rate at lower temperatures that occurs during SCF sintering could be considered to be related to this decrease in activation energy. [ABSTRACT FROM AUTHOR]