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In three-phase AC motors, three-phase AC voltage system is essential to generate a rotating magnetic field. Three- phase AC motors also require a three-phase inverter for variable speed and torque operation. In general, the number of switching devices used in three-phase inverter is not less than six and decreasing its number is difficult. This paper focuses on an LC ladder circuit consisting of linear inductors and capacitors. This paper presents a new operating method of the AC motor based on a propagating magnetic field. It is successfully excited by connecting one single-phase AC power supply to the end of the LC ladder circuit. The induction motor operated by the presented method produces torque as in general induction motors.

Purpose We evaluated the diagnostic performance of a clinically available deep learning-based computer-assisted diagnosis software for detecting unruptured aneurysms (UANs) using magnetic resonance angiography and assessed the functionality of the convolutional neural network (CNN) final layer score for distinguishing between UAN and infundibular dilatation (ID). Materials and methods EIRL brain aneurysm (EIRL_BA) was used in this study. The subjects were 117 UAN and/or ID cases including 100 UAN lesions (average sizes of 2.56 ± 1.45 mm) and 40 ID lesions (average sizes of 1.75 ± 0.41 mm) in any of internal carotid artery, middle cerebral artery, and anterior communicating artery, and 123 normal controls. The sensitivity, specificity, and accuracy of EIRL_BA were determined for UAN and ID or UAN only. Furthermore, the relationship between the lesion category and score was examined using a linear regression analysis model, and the receiver operating characteristic (ROC) analysis was used to assess whether the scores represent UAN-like characteristics. Results EIRL_BA showed a total of 203 candidates (an average of 1.73/case) in UAN and/or ID cases and 98 candidates (an average of 0.80/case) in normal controls. For diagnosing either UAN/ID, EIRL_BA showed an overall sensitivity of 80%, specificity of 84.2%, and accuracy of 83.7%, resulting in the positive likelihood ratio of 5.0. For diagnosing UAN only, the overall sensitivity of 89.0, specificity of 82.6%, and accuracy of 83.2% resulting in the positive likelihood ratio of 5.1. In a linear regression analysis, the scores significantly increased in the candidates’ first and second ranks in UAN (p Conclusion EIRL_BA is applicable for detecting small UAN, and the CNN’s final layer scores may be an effective index for discriminating UAN and ID and representing the likelihood of UAN.

Linker structures were systematically investigated for use in designing halogen-bond donor catalysts with two-point activation modes based on perfluoroiodobenzenes. Tetrafluorophenylene, phenylene, and acetylene were examined as potential linkers, and perfluoroiodobenzenes containing these linkers were successfully synthesized. Their activities were evaluated in terms of binding constant K (M–1) for Cl– and reaction yield (%) in the Mukaiyama- Mannich-type reaction of isoquinoline, and the catalyst with the acetylene linker exhibited the highest activity. The significance of the two-point mode was postulated based on the X-ray diffraction analysis of the acetylene-linked halogen-bond donor with two halogen-bond donor sites. Computational studies revealed the effect of the linker on Cl– binding via halogen bonding. Finally, the utility of the acetylene- linked two-point halogen-bond donor catalyst in the Mukaiyama- Mannich-type reaction was established using various substituted isoquinolines, chloroformates, and ketene silyl acetals.

This paper presents a new hybrid dynamic vibration absorber (DVA) using the Coriolis effect to reduce a rotational vibration observed in various kinds of rotating machinery. The Coriolis force is generated by a linear oscillatory actuator (LOA), which reciprocates in the radial direction. The effectiveness of the proposed hybrid DVA is confirmed through a MATLAB/Simulink simulation under passive and hybrid operations of the LOA. Moreover, an active torque ripple control is also presented for the purpose of applying this DVA to a switched reluctance motor (SRM). A Numerical simulation shows that the proposed hybrid DVA is able to reduce the torque ripple of the SRM by a non-sinusoidal position control of the LOA.

A special vibration mode called intrinsic localized mode (ILM) in a dispersed multi mass point-nonlinear spring system has been actively studied in solid-state physics and has a high application potential in engineering. Previous studies have only considered parameter-invariant systems, hence active control of the excited ILM is not possible. Therefore, even though the phenomena are very interesting, there are no applications to devices. In this paper, we propose a new paradigm of ILM by designing a dynamic nonlinear vibration system that can treat nonlinear spring properties in a variable manner depending on the applied current. By using variable spring characteristics, the localized vibration energy of the ILM can be freely transferred in unconventional way than before. The spring properties of the variable spring structure with applied current are investigated using finite element analysis. Then, numerical simulations in MATLAB show that the active control of the ILM is possible in a dynamic vibration system with variable spring characteristics.

To examine whether reasonable detection rate of endoscopically diagnosed lesions as adenoma ("endoscopic" adenoma detection rate [ADR]) could be calculated with a database generated from colonoscopy reports and whether it could be used as a surrogate colonoscopy quality indicator of "pathological" ADR.A lesion-by-lesion database of colonoscopies performed between 2010 and 2020 at eight Japanese endoscopy centers and corresponding pathology database were integrated. Differences in numbers of detected polyps, "endoscopic" and "pathological" adenomas, and what these differences could be attributed to were examined. Polyp detection rate (PDR), "endoscopic" and "pathological" ADRs, and correlation coefficients between "pathological" ADR and PDR or "endoscopic" ADR by each endoscopist were calculated.Overall, 129,065 colonoscopy reports were analyzed. Among a total of 146,854 polyps, more "endoscopic" adenomas (117,359) were observed than "pathological" adenomas (70,076), primarily because adenomas were not resected on site, rather than because of a misdiagnosis. In all patients analyzed, PDR, "endoscopic" and "pathological" ADRs were 56.4% (95% confidence interval [CI]: 56.2-56.7), 48.0% (95% CI: 47.7-48.3), and 32.7% (95% CI: 32.5-33.0), respectively. "Endoscopic" and "pathological" ADRs from each endoscopist showed a high correlation in hospitals where adenomas were usually resected at the time of examination.By appropriately describing endoscopically diagnosed lesions as "adenomas" in endoscopy reports, "endoscopic" ADR might be used as a surrogate colonoscopy quality indicator of "pathological" ADR (UMIN000040690).

Patients with superficial head and neck squamous cell carcinoma (HNSCC) can be completely treated by techniques of transoral surgery (TOS). The aim of this study was to evaluate the risk of metachronous multiple HNSCC arising after TOS based on alcohol dehydrogenase 1B (ADH1B) and aldehyde dehydrogenase 2 (ALDH2). We registered patients who underwent TOS for superficial HNSCC. Buccal cell samples were obtained by using a cotton swab to examine two single nucleotide polymorphisms in ADH1B and ALDH2 genotyping. We used Cox proportional hazards models to examine the risk of metachronous HNSCC. A total of 198 patients who underwent TOS for HNSCC were evaluated. In multivariate analysis, risks for second HNSCC were ADH1B*1/*1 [hazard ratio (HR), 1.88; 95% confidence interval (CI), 1.11–3.19; P = 0.02], ALDH2*1/*2 (HR, 2.11; 95% CI, 1.00–5.16; P = 0.048) and alcohol consumption before TOS (HR, 1.17; 95% CI, 1.06–1.27; P = 0.01). The 5-year incidence rates of second primary HNSCC in the temperance group and the non-temperance group were 20.8 and 46.5%, respectively (HR, 0.54; 95% CI, 0.31–0.92; P = 0.02). Cumulative development rates of third HNSCC in the temperance group and non-temperance group at 10 years were 11.3 and 36.1%, respectively (HR, 0.19; 95% CI, 0.03–0.65; P = 0.006). ADH1B*1/*1, ALDH2*1/*2 and moderate or heavy alcohol consumption before treatment are independent risk factors of metachronous HNSCC. Since it was shown that temperance decreased the incidences of second and third metachronous HNSCC, advice to discontinue alcohol drinking is necessary.

Background and Aim Fine‐needle biopsy (FNB) needles obtain more core samples and support the shift from cytologic to histologic evaluation; however, recent studies have proposed a superior diagnostic potential for liquid‐based cytology (LBC). This study compared the diagnostic ability of endoscopic ultrasound (EUS)‐guided FNB histology with a 22‐gauge Franseen needle (22G‐FNB‐H) and fine‐needle aspiration (FNA) LBC with a conventional 25‐gauge needle (25G‐FNA‐LBC). Methods We analyzed 46 patients who underwent both 22G‐FNB‐H and 25G‐FNA‐LBC in the same lesion during the same endoscopic procedure. This study evaluated the diagnostic ability of each needle, diagnostic concordance between needles, and incremental diagnostic effect of both needles compared to using each needle alone. Results The agreement rate for malignancy between both techniques was 93.5% (kappa value = 0.82). There was no significant difference in the diagnostic ability of both methods. 22G‐FNB‐H and 25G‐FNA‐LBC provided an incremental diagnostic accuracy in two (4.3%) cases and one (2.2%) case, respectively. Conclusion Our study demonstrated that the diagnostic accuracy of 25G‐FNA‐LBC and 22G‐FNA‐H for solid pancreatic lesions were comparable. A conventional 25‐gauge needle that punctures lesions with ease can be used in difficult cases and according to the skill of the endoscopist., We analyzed 46 patients who underwent both endoscopic ultrasound‐guided fine‐needle biopsy histology with a 22‐gauge Franseen needle and fine‐needle aspiration liquid‐based cytology with a conventional 25‐gauge needle in the same lesion during the same endoscopic procedure. There was no significant difference in the diagnostic ability of both methods. Our study suggests that a conventional 25‐gauge needle that punctures lesions with ease can be used in difficult cases and according to the skill of the endoscopist.

The need for mastering standard imaging techniques for convex endoscopic ultrasound (EUS) in the biliopancreatic regions has been increasing; however, large variations in the aptitude for achieving EUS competency hinder expert development. Therefore, we investigated the factors influencing the achievement of expert competency in EUS using a new assessment tool for multiple imaging items.Between January 2018 and February 2022, 3,277 consecutive EUS procedures conducted by five beginners (EUS number250), seven intermediate trainees (250-749), and two experts (≥750) were prospectively evaluated. Immediately after each EUS procedure, the success or failure of imaging for each item was recorded using a newly developed EUS assessment tool that requires 17 items to be photographed. After correcting for missing values using multiple imputation, learning curves of EUS scores were created, and a competency was set based on expert scores. Finally, a comparative analysis between high and low performers was performed to extract factors influencing EUS scores.Although three of the seven intermediates (43%, mean of 317 cases) achieved competency, none of the beginners achieved competency. During a comparative analysis, although no significant difference in the number of EUS performed was observed between the high and low performers, the former had significantly higher scores in the written test (theoretical knowledge).Our results showed that theoretical knowledge, rather than the number of EUS cases, may be a possible influencing factor for distinguishing high and low performers after treating 250 cases.

Objectives The Japan Endoscopy Database Project was initiated to develop the world's largest endoscopy data repository. This study describes the first phase of the colonoscopy project in Japan. Methods Data were aggregated offline by integrating information from the endoscopy database software from January 2015 through March 2017. The study population included all patients who underwent colonoscopy at eight centers. Results A total of 31,395 patients who underwent 38,497 colonoscopy procedures were registered. The majority of procedures were performed for screening (n = 14,156), followed by fecal immunochemical test positivity (n = 3960), abdominal symptoms (n = 3864), post-colorectal surgery surveillance (n = 3431), post-endoscopic treatment surveillance (n = 3757), thorough pre-treatment examination (n = 2822), and therapeutic purposes (n = 6507). In the screening group, advanced cancers, early cancers, and adenomas were diagnosed endoscopically in 2.1%, 1.3%, and 28.7% of cases, respectively, while in the fecal immunochemical test-positive group, they were diagnosed in 2.5%, 1.9%, and 41.6% of cases, respectively. The incidence of complications was 0.177% and 0.152% in the screening and fecal immunochemical test-positive groups, respectively. The therapeutic procedures included 1446 cold forceps polypectomy procedures, 4770 cold snare polypectomy procedures, 368 hot biopsies, 2998 hot snare polypectomy procedures, 9775 endoscopic or piecemeal endoscopic mucosal resections, and 1660 endoscopic submucosal dissections. A total of 173 procedure-related complications (0.82%) occurred in 21,017 therapeutic procedures performed in 15,744 patients. Conclusions The first phase of the Japan Endoscopy Database Project established the proportions of the diagnostic and therapeutic colonoscopy procedures, and complication rates in real-world settings.

Many researchers have been interested in a special vibrational mode called the intrinsic localized mode (ILM), which was found in solid-state physics. As a practical solution to use ILM, this article proposes a novel method of generating an alternating magnetic field which is completely different from the general three-phase alternating current method. An LC ladder circuit array is introduced to reproduce the ILM in an electrical system. Electromagnetic field analysis using the finite element method reveals that the ILM is able to transmit to the neighboring inductors at a constant velocity.

Initial staging by positron emission tomography/computed tomography (PET/CT) scanning is recommended for patients with diffuse large B-cell lymphoma (DLBCL). Whether both PET/CT and bone marrow biopsy (BMB) are required remains unclear. This study examined whether staging by PET/CT is sufficient. Participants with untreated DLBCL assessed using both PET/CT and BMB were included. Patients received independent diagnostic assessments from a radiologist and a hematopathologist. Both hematoxylin-eosin staining and CD20 immunostaining were performed to determine the bone marrow involvement in BMB. A total of 84 patients were included. The number of patients with positive bone marrow involvement identified by PET/CT and BMB was 16 (19%) and 22 (26%), respectively. Eight (10%) patients showed positive results in both tests. When considering BMB as a reference, PET/CT showed 36% sensitivity and 87% specificity, with positive and negative predictive values of 50% and 79%, respectively. BMB-positive patients had shorter progression-free (PFS) and overall (OS) survival than their BMB-negative counterparts. Compared to PET/CT-negative patients, patients with positive results did not show any significant differences in PFS and OS. However, among 16 PET/CT-positive patients, poor PFS and OS were observed among patients who were also BMB positive. BMB remains a mandatory step in staging of untreated DLBCL patients.

Selection criteria for self-expandable metal stents (SEMSs) with or without cover during palliative treatment of distal malignant biliary obstruction (DMBO) remain unclear. We evaluated factors associated with time to recurrent biliary obstruction (TRBO) in fully covered SEMSs (FCSEMSs) and uncovered SEMSs (UCSEMSs).We retrospectively analyzed consecutive patients with DMBO who received a SEMS. TRBO was determined using the Kaplan-Meier analysis, and complications were compared between the FCSEMS and UCSEMS groups. After TRBO-associated factors were extracted using multivariate competing-risks regression (CRR), propensity score-adjusted CRRs were performed to verify their robustness.There were 180 patients (66 FCSEMSs and 114 UCSEMSs) enrolled in this study. There was no significant difference between median TRBO in the FCSEMS and UCSEMS groups (275 vs. 255 days,UCSEMSs are a possible option for both patients with DMBO arising from PDAC and for patients with any DMBO receiving palliative care who should avoid SEMS-related complications.

The three-center-four-electron halogen bond (3c4e X-bond) presents a new design concept for catalysis. By integrating halogen(I) (X+: I+ or Br+), bis-pyridyl ligand NN, and non-nucleophilic counter anion Y, we developed non-metallic complex catalysts, [N···X···N]Ys, which exhibited outstanding activity and facilitated the Mukaiyama–Mannich-type reaction of N-heteroaromatics with ppm-level catalyst loading. The high activity of [N···X···N]SbF6 was clearly demonstrated. NMR titration experiments, CSI-MS, computations, and UV-vis spectroscopic studies suggest that the robust catalytic activity of [N···X···N]Y can be attributed to the unique feature of the 3c4e X-bond for binding chloride: i) the partial covalent nature transforms [N···X···N]+ complexation to sp2CH as a hydrogen bonding donor site, and ii) the noncovalent property allows for the dissociation of [N···X···N]+ for the formation of [Cl···X···Cl]–. This study introduces a new application of 3c4e X-bonds for catalysis via halogen(I) complexes.

The three-center-four-electron halogen bond (3c4e X-bond) presents a new design concept for catalysis. By integrating halogen(I) (X+: I+ or Br+), bis-pyridyl ligand NN, and non-nucleophilic counter anion Y. [N···X···N]SbF6, we developed non-metallic complex catalysts, [N···X···N]Ys, which exhibited outstanding activity and facilitated the Mukaiyama–Mannich-type reaction of N-heteroaromatics with sub-ppm-level catalyst loading. The high activity of [N···X···N]SbF6 was clearly demonstrated. NMR titration experiments, CSI-MS, computations, and UV-vis spectroscopic studies attribute the robust catalytic activity of [N···X···N]Y to the unique feature of the 3c4e X-bond for binding chloride: i) the partial covalent nature transforms [N···X···N]+ complexation to sp2CH as a hydrogen bonding donor site, and ii) the noncovalent property allows for the dissociation of [N···X···N]+ for the formation of [Cl···X···Cl]–. This study introduces a new application of 3c4e X-bonds to catalysis via halogen(I) complexes.

Background Gastric mixed adenoma-neuroendocrine tumors (NETs) are quite rare. In the 2019 world health organization classification of tumors of the digestive system, these were designated as a combination of grade 1 or grade 2 NETs and adenomas or tubular adenomas. There are no treatment guidelines for these tumors, and pathological and clinical studies are ongoing. Herein, we review previous case reports and present a case of gastric mixed adenoma-NET. Case summary A 66-year-old man underwent gastrointestinal endoscopy for the evaluation of upper abdominal pain. Histopathological examination of the biopsy specimen indicated the possibility of gastric cancer. A histopathological examination by endoscopic submucosal dissection showed a mixed adenoma-NET that was completely excised by endoscopic submucosal dissection. No recurrence was observed on gastrointestinal endoscopy at the 6-mo follow-up. Conclusion Clinicians' awareness of this rare tumor is important for its timely diagnosis and treatment.

The sample storage environment affects gut microbial profiles as assessed using 16S rRNA sequencing. However, the influence of storage condition on human salivary microbial profiles has not been well characterized. Here, we performed an observational study to assess the robustness of microbiota profiles in three different storage environments (-80°C after flash-freezing, -80°C, and -15°C; all for 14 days) compared to immediate DNA extraction using the MiSeq Illumina platform. Notably, the 16S rRNA V1-V2 region amplicon sequencing revealed no difference in microbiota profiles between the immediate extraction and each of three storage conditions. An almost perfect correlation was shown between the immediate extraction and the -15°C storage group for relative abundance at the genus and operational taxonomic unit levels. The intraindividual UniFrac distances among storage methods were significantly shorter than those of interindividual distances. None of the amount of extracted DNA, the α-diversity indices, or the relative abundance at the phylum/genus/operational taxonomic unit level differed among storage methods. These findings indicate that a storage temperature of -15°C without flash-freezing may be optimal in terms of cost advantage and simplicity in 16S rRNA sequencing-based salivary microbial research.

The terrestrialization of floodplains has become a concern to river managers and ecologists because it has degraded habitats for floodplain-dependent organisms. We examined the temporal distributions of the endangered deepbody bitterling (Acheilognathus longipinnis) throughout its life history, which is an autumn-spawning annual fish spending its egg and larval stages in unionid mussels and emerging in spring, to understand its population decline in the terrestrialized floodplains of the Kiso River, central Japan. We first validated our A. longipinnis environmental DNA (eDNA) sampling method and observed an 89.3% probability of consistency between the eDNA and the direct capture surveys of 56 floodplain waterbodies (FWBs). Subsequently, the temporal distributions with autumn dispersal (9 of 14 FWBs) were found using time-series eDNA samples collected from 14 FWBs on a floodplain with a length and width of 1.4 and 0.2 km, respectively. In the following spring, juveniles were only detected in the two FWBs connected to the river channel. Moreover, the direct capture data revealed that juveniles occurred in 52.9% (9/17) of the connected FWBs, but only in 5.1% (2/39) of the FWBs isolated from the river channel. Autumn dispersal of A. longipinnis would be disadvantageous for reproduction in terrestrialized floodplains with numerous isolated FWBs.