Nonlinear Modulation of Travelling Rolls in Magnetoconvection

Modulational dynamics of oscillatory travelling rolls in magnetoconvection is studied near the onset of a Hopf bifurcation. Using weakly nonlinear analysis, we derive an envelope equation of oscillatory travelling rolls in the plane perpendicular to an ambient vertical magnetic field.The envelope equation is the Davey-Stewartson (DS) equation with complex coefficients, from which we obtain criteria for the modulational (Benjamin-Feir) instability of oscillatory travelling rolls.Comment: 8 pages,late

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Comparison of various methods of analysis and finite elements in 3-D magnetic field analysis

In order to evaluate the most suitable method of analysis (A- phi or T- Omega method) and finite element (nodal or edge element) for a given problem, the features of each method and element have been investigated. The accuracy, computer storage, and CPU time of each method and element are compared for a 3-D nonlinear magnetostatic model and a 3-D eddy current model. The flux and eddy current densities calculated are compared with those measured. It is shown that the accuracy and the CPU time of the edge element are better than those of the nodal element. The A- phi method is better than T- Omega method for nonlinear problems from the viewpoint of convergence characteristics of nonlinear iterations.</p

“All-on-Four”コンセプトに基づいて即時荷重を適用したインプラントの力学解析

PURPOSE: The purpose of this study was to investigate the biomechanical behavior of immediately loaded implants in an edentulous mandible according to the "All-on-Four" concept. METHODS: A 3D-finite element model of an edentulous mandible was constructed. Four implants were placed between the bilateral mental foramen according to "All-on-Four" concept. A framework made of titanium or acrylic resin between the bilateral first molars was modeled. Immediate loading and a delayed loading protocol were simulated. A vertical load of 200N was applied at the cantilever or on the abutments region of the distal implants, simulating the absence of a cantilever. RESULTS: The peak principal compressive strains in the immediate loading models resulted in 24.0-35.8% and 26.4-39.0% increases compared with the delayed loading models under non-cantilever loading and cantilever loading, respectively. The loading position greatly affected the principal compressive and tensile strain values. The peak principal compressive strains in non-cantilever loading resulted in a 45.3-52.6% reduction compared with those in cantilever loading. The framework material did not influence the peak compressive and tensile strain. The maximum micromotion at the bone-implant interface in the immediate loading models was 7.5-14.4μm. CONCLUSIONS: Mandibular fixed full-arch prostheses without cantilevers may result in a favorable reduction of the peri-implant bone strain during the healing period, compared with cantilevers. The maximum micromotion was within the acceptable limits for uneventful implant osseointegration in the immediate loading models. Framework material did not play an important role in reducing the peri-implant bone strain and micromotion at the bone-implant interface.博士（医学）・乙第1398号・平成29年3月15日Copyright © 2016 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved

Russell Body Gastritis Concurrent with Eosinophilia: a case report

A 64-year-old male patient with a histological diagnosis of Russell body gastritis and with eosinophilic infiltrate in biopsy specimens is reported. The patient continued hemodialysis and pseudomembranous enteritis was contracted. Upper gastrointestinal endoscopy was performed due to poor appetite and blood eosinophilia. During endoscopy, a flare, swollen mucous membrane, and multiple verrucous erosions were noted in the gastric antrum. Biopsy and histopathological examination of gastric mucosa showed infiltration of plasma cells containing Russell bodies and eosinophils. Plasma cells containing Russell bodies were positive for CD138, immunoglobulin A (IgA) and kappa-light chain. Giemsa stained biopsy specimen revealed that the patient was negative for Helicobacter pylori. The patient was diagnosed with Russell body gastritis with eosinophilia. This is the first report of Russell body gastritis concurrent with eosinophilia. We discussed the possible correlation between the presence of plasma cells containing Russell bodies and gastric eosinophilia

Salvage esophagectomy under bilateral thoracotomy after definitive chemoradiotherapy for aorta T4 thoracic esophageal squamous cell carcinoma: Report of a case

AbstractIntroductionThe surgical technique for esophagectomy to treat esophageal malignancies has been improved over the past several decades. Nevertheless, it remains extremely difficult to surgically treat patients with locally advanced T4b tumors invading the aorta or respiratory tract.Presentaion of caseA 37-year-old Japanese man was diagnosed with T4b (descending aorta) N2M0, Stage IIIC middle thoracic esophageal squamous cell carcinoma. He was initially treated with definitive CRT followed by 3 courses of DCF. After the DCF, CT showed that the main tumor had shrunk and appeared to have separated from the descending aorta. Therefore we decided to perform a salvage esophagectomy. Because we needed the ability to closely observe the site of invasion to determine whether aortic invasion was still present, half the esophageal resection was performed under right thoracotomy, but the final resection at the invasion site was performed under left thoracotomy. Consequently, the thoracic esophagus was safely removed and aortic replacement was avoided. The patient has now survived more than 30 months after the salvage esophagectomy with no additional treatment for esophageal cancer and no evidence of recurrent disease.DiscussionBecause this and the previously reported procedures, each have particular advantages and disadvantages, one must contemplate and select an approach based on the situation for each individual patient.ConclusionSalvage esophagectomy through a right thoracotomy followed by careful observation of the invasion site for possible aortic replacement through a left thoracotomy is an optional procedure for these patients

Semiconductor optical modulator by using electron depleting absorption control

Operation of a newly proposed semiconductor optical modulator based on absorption control by electron depletion around a p-n junction is demonstrated, forming preliminary structures of waveguide-type as well as panel-type (or surface-illuminated type) devices. The optical absorption is occurred at the intrinsic energy levels in the band structure not at the extended state into the band-gap. Performance of 35 dB on-off extinction ratio for 4 V variation of the applied voltage was obtained in a waveguide type device. Validity of the proposed mechanism were confirmed by getting large change of the absorption coefficient of around 5000 cm-1 over wide wavelength range of 30 nm