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This study aims to design a nervous system model to drive the realistic muscle-driven legs for the locomotion of a quadruped robot. We evaluate our proposed nervous system model with a hind leg simulated model and robot. We apply a two-level central pattern generator for each leg, which generates locomotion rhythms and reproduces cat-like leg trajectories by driving different sets of the muscles at any timing during one cycle of moving the leg. The central pattern generator receives sensory feedback from leg loading. A cat simulated model and a robot with two hind legs, each with three joints driven by six muscle models, are controlled by our nervous system model. Even though their hind legs are forced backward at a wide range of speeds, they can adapt to the speed variation by autonomously adjusting its stride and cyclic duration without changing any parameters or receiving any descending inputs. In addition to the autonomous speed adaptation, the cat hind leg robot switched from a trot-like gait to a gallop-like gait while speeding up. These features can be observed in existing animal locomotion tests. These results demonstrate that our nervous system is useful as a valid and practical legged locomotion controller.

An ethyl-substituted diamidine, 1,8-bis(N,N'-diethylamidino)anthracene (1), for the recognition of dicarboxylic acids has been designed and synthesized. The complexation of diamidine 1 with dicarboxylic acids 3, 4 and α,ω−dicarboxylic acids 6 (C6-C11), showed the formation of 1:1 complexes in CH3CN. On the other hand, for the complexation with a monocarboxylic acid and α,ω−dicarboxylic acids 6 (C3-C5), formation of the amidinium 1·2H+ was observed. The crystal structures of the 1:1 complexes of the diamidine 1 and the α,ω−dicarboxylic acids 6 were obtained, and an unusual “U-shaped conformation” of 6 was observed. Furthermore, fluorescence spectra of the diamidine 1 showed “structural vibrational bands” derived from the anthracene unit after recognition of the α,ω−dicarboxylic acids (C6-C11). However, for the formation of the dissociated amidinium 1·2H+, broad fluorescence bands were observed (without a vibrational structure). Consequently, the stability of the formed complexes can be analyzed by the patterns (vibrational structures) of the fluorescence spectra.

A 1,8-diphenylnaphthalene-based diamidine (1) ‘turn-on’ fluorescent probe for the detection of dicarboxylic acids has been designed and synthesized. The fluorescence spectra of the diamidine 1 with carboxylic acids that showed two different fluorescence bands, which corresponded to the amidinium-carboxylate (λem=410–430 nm) and amidinium (λem=440–470 nm as a broad band, which consisted from two peaks) formation, were confirmed by DOSY NMR and TD-DFT calculations. The complexation of diamidine 1 with dicarboxylic acids, which have sufficient distances between the two carboxylic groups for binding to the diamidine 1 (dicarboxylic acids 3, 4, and α,ω-dicarboxylic acids 6 (C6–C20)), showed the formation of 1:1 complexes (i.e., amidinium-carboxylate formation). On the other hand, for the complexation with monocarboxylic acids and dicarboxylic acids having insufficient distances between the two carboxylic groups (benzoic acid 5, acetic acid 7, and α,ω-dicarboxylic acids 6 (C3–C5)), formation of the amidinium (1·2H+) was observed. Relatively similar binding constants (10−5) for the complexation of the diamidine 1 with dicarboxylic acids 6, which depend on their chain length (strain), were observed due to the flexibility of the 1,8-diphenylnaphthalene unit. Additionally, for the complexation of the diamidine 1 with dicarboxylic acids, higher fluorescence quantum yields (Φfl: up to 80%) were observed when compared to the binding of the diamidine 2 (Φfl: up to 35%).

Light-scattering measurements were carried out on polyisoprene (PI) samples with weight-averaged molecular weights (Mws) ranging from 1.1 × 103 to 2.7 × 104 in 1,4-dioxane at and near the theta point, 35.3 °C, which is defined as the temperature at which the second virial coefficient A2 for sufficiently high Mw (larger than 1 × 104) vanishes. It was found that A2 at the theta point decreases with decreasing Mw for Mw

Background/Aims: Stent migration occurs frequently, but the prevention of complications resulting from covered self- expandable metal stents (C-SEMSs) remains unresolved. We prospectively assessed a newly developed C-SEMS, a modi- fied covered Zeo stent (m-CZS), in terms of its antimigration effect. Methods:�Between February 2010 and January 2011, an m-CZS was inserted into 42 patients (31 initial drainage cases and 11 reintervention cases) at a tertiary referral center and three affiliated hospitals. The laser-cut stent was flared for 1.5 cm at both ends, with a 1 cm raised bank located 1 cm in from each flared end. The main outcome of this study was the rate of stent migration, and second- ary outcomes were the rate of recurrent biliary obstruction (RBO), the time to RBO, the frequencies of complications, and overall survival. Results:�Of the 31 patients with initial drainage, stent migration occurred in four (12.9%, 95% con- fidence interval, 5.1% to 29.0%), with a mean time of 131 days. RBO occurred in 18 (58%), with a median time to RBO of 107 days. Following previous C-SEMS migration, seven of 10 patients (70%) did not experience m-CZS migration until death. Conclusions:�m-CZSs with antimigration properties ef- fectively, although not completely, prevented stent migration after stent insertion. (GutLiver�2013;7:725-730)

Light scattering and viscosity measurements were made on dilute solutions of a polymacromonomer consisting of a polystyrene main chain and polyisoprene (PI) side chains, which was synthesized by an...

We show the preparation of honeycomb-nanoparticles hybrid structures by simple casting of nanoparticle dispersion onto the self-organized honeycomb-patterned films. The polystyrene honeycomb-patterned films were prepared by the “Breath Figure” method. The hydrophobic polystyrene honeycomb-patterned films were treated by UV-O 3 to improve the wettablity. A newly developed sliding apparatus were used for embedding the submicron polystyrene particles. Finally, we obtained the multiple-periodic structure of the honeycomb-patterned film and nanoparticles.

The atomic-scale surface roughness of thermal oxides formed on Si(100) were studied as a function of oxide film thickness up to 3.15 nm using non-contact mode atomic force microscopy (NC-AFM). The height deviation of the oxide surface is limited to within a single atomic-step height of 0.135 nm on a Si(100) surface below the thickness of about 1 nm, but above this thickness, it increases with an increase in thickness at 700°C and then decreases drastically by the oxidation at 900°C and becomes comparable with the surface roughness before the oxidation. Oscillations in surface roughness with constant amplitude and period intervals of 0.19 nm were observed in the thickness range studied. Surface morphologies are affected strongly by the oxidation temperature, while the interface structures are affected weakly by the oxidation temperature. The area where the layer-by-layer oxidation reaction occurs is on the order of 5 nm in diameter at 700°C and increases significantly with an increase in oxidation temperatures up to 800°C and 900°C.

In the present study, crystal aluminum alloy with fine grain was used for micro-forming. The micro-forming was tried on the melt spun Al-14mass%Si foil by cold rolling. The ability of micro-forming of a metallic alloy by cold forming was investigated. A V-shape die was used with depths of 1, 3, 5 and 10 μm. Rolling speed was 1 m/min. The as-cast foil was cold rolled and polished to make the surface smooth. The polished foil was annealed at 400°C before the micro-forming. The thickness of the foil used for microforming was 100 μm.

This paper proposes a induction motor drive using magnetic energy recovery switch (MERS). The MERS is a series compensation device and it can control the load voltage and input power factor. Stability problem because of self-excitation was found. However, this could be solved with voltage feedback control. Small scale experiments and field test results are reported.

The critical amount of nitrogen atoms at the interface, above which the roughness of the oxynitride/Si(100) interface increases, was studied using noncontact-mode atomic force microscopy and X-ray photoelectron spectroscopy. The interface roughness was found to increase upon increasing the amount of nitrogen atoms at and near the interface if the amount of nitrogen atoms is greater than 0.37 monolayers. This increase in interface roughness was found to be reflected in an increase in surface roughness of almost the same amount.