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This paper describes a new user-friendly hybrid surface mesh-generation method coupled with a modified hybrid volume mesh-generation method for viscous flow simulations. A suppressed marching-direction method is proposed to improve the quality of meshes at concave corners on surfaces and in volumes, such as aircraft wing–body junctions. Good-quality semistructured quadrilateral faces can be created around selected geometrical features with minimum user interventions using an advancing-layers-type method with a special treatment at concave corners. The hybrid volume mesh-generation method proposed by Ito et al. (Ito,Y., Shih, A. M., Soni, B. K., and Nakahashi, K., “Multiple Marching Direction Approach to Generate High Quality Hybrid Meshes,” AIAA Journal, Vol. 45, No. 1, 2007, pp. 162–167 and Ito, Y., Shih, A. M., and Soni, B. K., “Hybrid Mesh Generation with Embedded Surfaces Using a Multiple Marching Direction Approach,” International Journal for Numerical Methods in Fluids, Vol. 67, No. 1, 2011, pp. 1–7...

Background Tracheal immunogenicity has been controversial. Although replacement of allotracheal epithelia by the host epithelia has been reported in rat orthotopic tracheal grafting, the immunological effect of epithelial replacement is still uncertain. Methods We performed orthotopic tracheal grafting of nine cartilage rings in the following groups: 1, Lewis → Lewis ( n = 30); 2, ACI → DA ( n = 25); 3, Lewis → F344 ( n = 23); 4-A, DA → Lewis ( n = 41); 4-B, DA → Lewis with tacrolimus therapy (1 mg/kg/d for 10 days) starting from the day of the operation ( n = 31); 4-C, retransplantation of DA allografts to secondary naive Lewis rats 10 or 15 days after primary grafting ( n = 11); 4-D, DA → Lewis with tacrolimus therapy starting from postoperative day 10 ( n = 6). Survival times and histopathology were assessed. Epithelial replacement was evaluated by immunohistochemistry. Results All rats survived in groups 1, 2, and 3. Even in the fully histoincompatible group 4-A, survival ratio on day 120 was 15%. Epithelial replacement was in progress on day 10 in this group. However, all tacrolimus-treated rats died by day 54 and epithelial replacement did not occur on days 30 and 50 in group 4-B. In group 4-C, retransplantation after complete epithelial replacement increased the long-surviving rats. In group 4-D, all rats receiving tacrolimus therapy after complete epithelial replacement survived over 120 days. Conclusions These results suggest that complete replacement of tracheal epithelia by the host promotes spontaneous acceptance of orthotopic tracheal allografts in rats.

Si3N4 ceramic specimens were ground under different conditions with high-speed (wheel speed: 55m/s) and speed-stroke (table speed: 45-90m/min). The grindability was evaluated by grinding force, specific grinding energy and grinding ratio in comparison with conventional surface grinding. The strength degradation and surface roughness of ground workpieces were examined. The main results are summarized as follows. (1) This grinding conditions showed lower normal grinding force and specific grinding energy in a higher stock removal rate. And, the strength degradation and the surface roughness were not changed significantly even by increasing stock removal rate. (2) The lower normal grinding force and specific grinding energy were caused by a lower mean value of the maximum grain depth of cut. (3) This grinding conditions showed lower specific grinding energy in increasing stock removal and higher grinding ratio.

This paper describes a new user-friendly hybrid surface mesh generation method coupled with a modified hybrid volume mesh generation method for viscous flow simulations. A suppressed marching direction method is proposed to improve the quality of meshes at concave corners on surfaces and in volumes, such as aircraft wing-body junctions. Goodquality semi-structured quadrilateral faces can be created around selected geometrical features with minimum user-interventions using an advancing-layers type method with a special treatment at concave corners. The hybrid volume mesh generation method proposed by Ito et al. has also been modified so that it creates good-quality hexahedra along concave corners. Computational simulations have been performed using resulting meshes to demonstrate the capability of the new methods.

1. 1. Single smooth muscle cells were isolated from guinea-pig taenia caeci by digestion with collagenase. 2. 2. The 45 Ca desaturation curve from isolated cells, which were previously washed with Ca 2+ -free solution containing EGTA in Ca 2+ -free modified Locke solution, consisted of three components (half-time: 1.0, 3.8 and 12.4 min). 3. 3. The 45 Ca efflux from isolated cells in the third component was significantly increased by caffeine. This increase was suppressed by procaine, but was not affected by La 3+ . 4. 4. These results suggest that, in guinea-pig taenia caeci, there are at least four Ca 2+ compartments: superficial low and high affinity bound Ca 2+ and cellular low and high affinity bound Ca 2+ . Caffeine releases Ca 2+ from the cellular high affinity binding sites.