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To visualize and characterize the unsteady properties of the wake trailing behind a wind turbine, we propose a novel numerical methodology in this study. Through a wind-tunnel experiment using a smoke generator, we succeeded in visualizing a compact-type small-scale wind turbine wake using continuous scalar plumes from a single point source. Next, to simulate the above wind-tunnel experiment, we proposed a method using the passive scalar advection–diffusion equation based on a high-fidelity large-eddy simulation (LES). The actuator-line method (ALM) was adopted for the wind turbine model. We succeeded in qualitatively reproducing the wake visualization experiment in the wind tunnel described above and verified the effectiveness of the proposed numerical visualization method. To evaluate the characteristics of wakes generated by wind turbines in more detail, we conducted a quantitative comparison using a disk-shaped volume source with the same size as the swept area, set behind the wind turbine model. The results indicated that the non-dimensional time-averaged passive scalar profile in the near- and far-wake regions qualitatively matched the shape of the stream-wise velocity profile, despite having opposite signs. In other words, it was shown that if a disk-shaped volume source with the same size as the swept area is placed just behind the wind turbine, it is possible to accurately predict the behavior of the wind turbine wake. Finally, to validate the proposed method for wind farm wake management, we performed a visualization of wake flows in a virtual offshore wind farm consisting of 12 wind turbines with short separation distances. Through detailed comparison of two types of numerical results with different wind directions, we showed that the proposed method can effectively demonstrate the range of spatial influence of the wakes formed by the wind turbine with special attention.

Aims/Introduction An efficient screening strategy for identification of cognitive dysfunction remains a clinical issue in the management of elderly adults with diabetes. A magnetic resonance imaging voxel‐based specific regional analysis system for Alzheimer’s disease (VSRAD) has been developed as an automated brain morphometry system that includes the hippocampus. We carried out a multicenter retrospective study to evaluate the utility of VSRAD for screening cognitive dysfunction in diabetes outpatient clinics. Materials and Methods We enrolled patients with diabetes aged >65 years who underwent brain magnetic resonance imaging scans for the purpose of a medical checkup between November 2018 and May 2019. Patients who were already suspected or diagnosed with mild cognitive impairment and/or dementia as well as those with a history of cerebrovascular disease were excluded. Results A total of 67 patients were enrolled. Five patients were diagnosed with mild cognitive impairment or dementia (clinical cognitive dysfunction). Patients with clinical cognitive dysfunction showed a significantly higher z‐score in VSRAD analysis (2.57 ± 0.47 vs 1.15 ± 0.55, P, We evaluated the utility of the voxel‐based specific regional analysis system of Alzheimer's disease, an automated brain morphometry system that includes the hippocampus, for screening unrecognized cognitive dysfunction in elderly patients with diabetes. This is the first report to assess the association between hippocampal atrophy and cognitive dysfunction by an automated voxel‐based morphometry system in clinical diabetes practice. The results suggest that the voxel‐based specific regional analysis system of Alzheimer's disease can be useful for early identification of cognitive dysfunction in the elderly with diabetes.

A straightforward solution for minimizing the cost of major materials used in motors, such as permanent magnets and silicon steel sheets, is to reduce the motor size as far as possible. However, there is a trade-off between the motor size and temperature rise in the motor that should be taken into account while reducing the motor size. For achieving this, we have been developing an optimal design method based on a combination of a thermomagnetic field coupling analysis and a direct search algorithm. This paper reports the details of this design method. A multipole permanent magnet synchronous motor of an outer rotor is the test motor. The results of the torque-density-maximization problem involving constraints on the terminal voltage, coil-temperature rise, and demagnetization of the permanent magnet are shown. The usefulness of our method is also demonstrated. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 183(2): 29–38, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22346

A straightforward solution for minimizing the cost of major materials used in motors, such as permanent magnets and silicon steel sheets, is to reduce the motor size as far as possible. However, there is a trade-off between the motor size and temperature rise in the motor that should be taken into account while reducing the motor size. For achieving this, we have been developing an optimal design method based on a combination of a thermo-magnetic field coupling analysis and a direct search algorithm. This paper reports the details of this design method. An outer-rotor, multipole permanent-magnet synchronous motor is the test motor. The results of the torque-density-maximization problem involving constraints on the terminal voltage, coil-temperature rise, and demagnetization of the magnet are shown. The usefulness of our method is also demonstrated.

In order to clarify the basic aerodynamic mechanisms of the hovering flight of the dragonfly, numerical simulations of the unsteady viscous flow around a tandem wing configuration have been performed using a three -dimensional Navier -Stokes code. The flow simulations are conducted for Anax parthenope julius as a typical dragonfly model. The total lifting force and specific necessary power predicted by the present simulation show close agreement with those observed experimentally for the present dragonfly model. The present code is furth er validated by comparing the results of the simulation with the experimental values of total lift and stroke -plane angle obtained using a robot.

In an experiment using a single-degree-of-freedom (pitching) flutter model, which simulates the typical section of a forward-swept wing, shock-stall flutter, which is induced by large-scale shock-induced flow separation, has been observed by a schlieren system with a high-speed video camera. The experimental results are compared with computational ones to evaluate the numerical analysis code using the compressible Navier-Stokes equations. The mechanism of the shock-stall flutter is made clear by considering the relations between the pitching moments vs angle of attack and the flow patterns around the airfoil, which are obtained by the experimental flow visualization and the numerical simulation

We observed the microstructure of perovskite thin films, and compared the results with their colossal magnetoresistance (CMR) properties. Epitaxial or textured films of La1-xSrxMnyO3-δwere prepared by rf sputtering on (100)SrTiO3 and (110)sapphire single crystal substrates. The films were investigated by X-ray diffraction, magnetoresistance measurement, and transmission electron microscopy (TEM). The magnetoresistance of the films deposited on SrTiO3 substrate shows similar temperature dependence to that of bulk single crystals. The temperature dependence of the magnetresistance in the films on a sapphire substrate is different from that in bulk single crystals, that is, the magnetoresistance decrease monotonously with increasing temperature. We revealed by TEM observations that the films on SrTiO3 substrate grew epitaxially with a number of defects, however, the films on sapphire substrate grew with a columnar structure and showed no epitaxy. Therefore, the difference in the MR properties is attributed to the lattice mismatch between films and substrates.

Transmigration of monocytes to the subendothelial space is the initial step in atherosclerotic plaque formation and inflammation. Integrin activation and chemotaxis are two important functions in monocyte transmigration. To delineate the signaling cascades leading to integrin activation and chemotaxis by monocyte chemoattractant protein-1 (MCP-1), we investigated the roles of MAPK in THP-1 cells, a monocytic cell line. MCP-1 stimulated beta1 integrin-dependent, but not beta2 integrin-dependent cell adhesion in a time-dependent manner. MCP-1-mediated cell adhesion was inhibited by a MEK inhibitor, but not by a p38-MAPK inhibitor. By contrast, MCP-1-mediated chemotaxis was inhibited by the p38-MAPK inhibitor, but not by the MEK inhibitor. These data indicate that ERK is responsible for integrin activation and that p38-MAPK is responsible for chemotaxis mediated by MCP-1. This study demonstrates that two distinct MAPKs regulate two dependent signaling cascades, leading to integrin activation and chemotaxis induced by MCP-1 in THP-1 cells.

Monocyte chemoattractant protein 1 (MCP-1) has a crucial role in atherogenesis and inflammation. However, MCP-1-mediated signalling pathways in monocytes have not been fully elucidated. In the present study we investigated the role of tyrosine kinases such as proline-rich tyrosine kinase 2 (Pyk2) in MCP-1-mediated signal transduction in the monocytic cell line THP-1. Pyk2 was tyrosine phosphorylated very quickly after stimulation with MCP-1. We found that Lyn, Shc and paxillin were also tyrosine phosphorylated by MCP-1. We examined the association of these molecules by immunoprecipitation and immunoblot analysis. The association of Pyk2 with Lyn was dependent on stimulation with MCP-1 and on tyrosine phosphorylation of Pyk2. Phosphorylation of p38 was also dependent on tyrosine phosphorylation of Pyk2. However, the association of Pyk2 with paxillin and Grb2 was not affected by stimulation with MCP-1. Phosphorylation of ERK (extracellular-signal-regulated protein kinase) was not affected by overexpression of kinase-negative Pyk2. Our results indicate that Pyk2 forms a complex with paxillin, Grb2 and Lyn in THP-1 cells. However, Pyk2 is not always involved in MCP-1-mediated signalling pathways.

Transmigration of monocytes to the subendothelial space is the initial step of atherosclerotic plaque formation and inflammation. Integrin activation and chemotaxis are two important functions involved in monocyte transmigration. To delineate the signaling cascades leading to integrin activation and chemotaxis by monocyte chemoattractant protein-1 (MCP-1), we have investigated the roles of MAPK and Rho GTPases in THP-1 cells, a monocytic cell line. MCP-1 stimulated beta1 integrin-dependent, but not beta2 integrin-dependent cell adhesion in a time-dependent manner. MCP-1-mediated cell adhesion was inhibited by a MEK inhibitor but not by a p38-MAPK inhibitor. In contrast, MCP-1-mediated chemotaxis was inhibited by the p38-MAPK inhibitor but not by the MEK inhibitor. The inhibitor of Rho GTPase, C3 exoenzyme, and a Rho kinase inhibitor abrogated MCP-1-dependent chemotaxis but not integrin-dependent cell adhesion. Further, C3 exoenzyme and the Rho kinase inhibitor blocked MCP-1-dependent p38-MAPK activation. These data indicate that ERK is responsible for integrin activation, that p38-MAPK and Rho are responsible for chemotaxis mediated by MCP-1, and that Rho and the Rho kinase are upstream of p38-MAPK in MCP-1-mediated signaling. This study demonstrates that two distinct MAPKs regulate two dependent signaling cascades leading to integrin activation and chemotaxis induced by MCP-1 in THP-1 cells.