Pinning field representation using play hysterons for stress-dependent domain-structure model

© 2019 To predict the stress-dependent magnetization properties of silicon steel using a multiscale magnetization model called assembled domain structure model, pinning field models are developed using the play model. The hysteretic property of pinning field is identified from measured BH loops under stress-free condition. From the unidirectional hysteretic property, the distribution of the play hysterons is determined via an identification method that uses scalar and vector play models under the assumption of 2D or 3D distribution of crystal orientations. The loss properties of non-oriented silicon steel under compressive and tensile stresses are predicted successfully using an energy minimization process without parameter fitting to the stress-dependent measurement results

Anisotropic Vector Play Model and its Application in Magnetization Analysis

An anisotropic vector play model was developed by the superposition of scalar play models. An analytical identification method was derived for a uniaxially anisotropic term. Computed BH loops accurately reconstructed the measured anisotropic hysteretic characteristics of non-oriented (NO) silicon steel sheet. Its application to magnetization analysis by a physical magnetization model using multi-domain particles enhanced the prediction accuracy of the stress-dependent loss property

Model Order Reduction of Cage Induction Motor With Skewed Rotor Slots Using Multiport Cauer Ladder Network Method

A method for efficiently deriving a reduced-order model of a cage induction motor (IM) with skewed rotor slots is proposed based on the multiport Cauer ladder network (CLN) method. This article presents several formulations of the multiport CLN method for the skewed rotor, in which the continuity of the bar currents and the space harmonics included in the air-gap flux density waveform are treated differently. The effectiveness of the developed methods was verified from the viewpoints of computational accuracy and cost through application to a practical cage IM with skewed rotor slots

Serum IgG4 as a biomarker reflecting pathophysiology and post-operative recurrence in chronic rhinosinusitis

Background: Type 2 chronic rhinosinusitis (CRS), especially eosinophilic CRS (ECRS), is an intractable upper airway inflammatory disease. Establishment of serum biomarkers reflecting the pathophysiology of CRS is desirable in a clinical setting. As IgG4 production is regulated by type 2 cytokines, we sought to determine whether serum IgG4 levels can be used as a biomarker for CRS. Methods: Association between the serum IgG4 levels and clinicopathological factors was analyzed in 336 CRS patients. Receiver operating characteristics (ROC) analysis was performed to determine the cut-off value of serum IgG4 levels that can be used to predict the post-operative recurrence. Results: Serum IgG4 levels were significantly higher in patients with moderate to severe ECRS versus those with non to mild ECRS. The levels were also significantly higher in asthmatic patients and patients exhibiting recurrence after surgery compared to controls. ROC analysis determined that the best cut-off value for the serum IgG4 level to predict the post-operative recurrence was 95 mg/dL. The corresponding sensitivity and specificity were 39.7% and 80.5%, respectively. When we combined the two cut-off values for the serum IgG4 and periostin, patients with high serum levels of either IgG4 or periostin exhibited a high post-operative recurrence (OR: 3.95) as compared to patients having low serum levels of both IgG4 and periostin. Conclusions: The present results demonstrate that the serum IgG4 level is associated with disease severity and post-operative course in CRS. In particular, the combination of serum IgG4 and periostin could be a novel biomarker that predicts post-operative recurrence

Preparation of porous thin-film polymethylsiloxane microparticles in a W/O emulsion system

Porous thin-film polymethylsiloxane microparticles have been prepared successfully from octyltrichlorosilane and methyltrichlorosilane in (water/oil) W/O emulsion systems by using several oil phases and changing the amount of the silanes or of the surfactant Span 60. Hollow microspheres of various shell thicknesses (120-180 nm) and high surface area were prepared by using four types of nonpolar solvents as the oil phase of the W/O emulsion system. The diameter of the spheres can also be controlled (1-1.6 mu m) by using different oil phases. The results of thermal analysis, nitrogen adsorption isotherm, infrared spectra and X-ray diffraction data showed that hollow microspheres of amorphous polymethylsiloxane with high surface area (360-385 m(2)g(-1)) can be obtained by heating the spheres in air at 673 K; the polymethylsiloxane microspheres become nonporous silica particles after calcination at 873 K for 3 h. Cup-shape microparticles of polymethylsiloxane with nano-order thickness (20-120 nm) were prepared by reducing the amount of silanes in the mixture. Small hollow particles were prepared by replacing a portion of the octyltrichlorosilane with Span 60.ArticlePOLYMER JOURNAL. 47(6): 449-455 (2015)journal articl

Particle simulation approach for subcellular dynamics and interactions of biological molecules

BACKGROUND: Spatio-temporal dynamics within cells can now be visualized at appropriate resolution, due to the advances in molecular imaging technologies. Even single-particle tracking (SPT) and single fluorophore video imaging (SFVI) are now being applied to observation of molecular-level dynamics. However, little is known concerning how molecular-level dynamics affect properties at the cellular level. RESULTS: We propose an algorithm designed for three-dimensional simulation of the reaction-diffusion dynamics of molecules, based on a particle model. Chemical reactions proceed through the interactions of particles in space, with activation energies determining the rates of these chemical reactions at each interaction. This energy-based model can include the cellular membrane, membranes of other organelles, and cytoskeleton. The simulation algorithm was tested for a reversible enzyme reaction model and its validity was confirmed. Snapshot images taken from simulated molecular interactions on the cell-surface revealed clustering domains (size ~0.2 μm) associated with rafts. Sample trajectories of raft constructs exhibited "hop diffusion". These domains corralled the diffusive motion of membrane proteins. CONCLUSION: These findings demonstrate that our approach is promising for modelling the localization properties of biological phenomena