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A bilateral wrist joint training and rehabilitation mechanism is designed to meet the requirements of bilateral passive training better than unilateral active training. The rehabilitation mechanism adopts two spatial reverse double crank parallel sub mechanisms. The forward kinematics of the mechanism is analyzed in the spherical coordinate system, and the motion relationship of the two platforms is obtained. The Euler angles of the rolling, pitching and virtual yaw motions of the two platforms are measured, and the front and back muscles are measured simultaneously in the three motion modes. The experimental data shows that when the mechanism is rolling, the angular displacements of both platforms are equal in magnitude and opposite in direction, while the mechanism is pitching, the angular displacements of both platforms are the same in magnitude and direction. The maximum and average electromyography （EMG） values of anterior and posterior muscles measured during the bilateral active training are 319.65 mV and 352.2 mV higher than those measured during the resting state, and 155.9 mV and 184 mV higher than those measured during the unilateral passive training, respectively. The above results show that the developed bilateral training machine has mirror symmetry, can play a training effect on the wrist joint, and the training effect is better than that of the unilateral training.

Gyrocheilos is a small genus of Gesneriaceae endemic to hight altitude mountains in Southwest China and Guangdong Province, with only five species. This genus is characterized by laterally bending style, which curves 90° at the top of the style and the stigma right at the mouth of floral tube. This unusual floral trait may have special evolutionary and adaptive mechanisms. In this paper, three Gyrocheilos species, i.e. G. chorisepalus, G. retrotrichus, G. microtrichus were examined to figure out the developmental patterns of floral lateral bending. Breeding systems, floral syndrome and pollination processes were also studied in G. retrotrichus at Dawuling Mountain, Guangdong Province, to explore its pollination adaptations. The results were as follows: (1) G. microtrichus had only left-bending style, while right-bending style were observed in several flowers (2% -3% of the total flowers) of G. chorisepalus and G. retrotrichus, although the individuals and populations were dominated by left-bending style. (2) Pollination observation found that style lateral bending occurred at the early stage of floral bud in G. retrotrichus, with two fertile stamens were anther-united and hidden at the middle of the floral throat, and there was no left and right mirror symmetry relationship with the lateral style. (3) The pollen-ovule ratio (P/O) was (456.98 ± 15.55), belonging to facultative outcross breeding system. G. retrotrichus had a certain pollen limitation and self-pollination, but the germination rate of outcross seeds was higher, and there might be inbreeding decline. (4) There were few floral visitors and the frequency was low of G. retrotrichus. The main floral visitors were Halictidae, Bombus and Syrphidae. Bombus were large, and they landed on the bent style and the lower lip of the petals when visiting flowers. The side and lower part of the chest could effectively contact the stigma. (5) The detected reflected lights of flowers were composed of purple and blue-purple lights and the lower lips and outer floral tube with the highest reflection intensity, more likely to attract bees to land on the corolla's lower lip. Molecular phylogeny indicated that the closest genus of Gyrocheilos was Didymorcarpus, which was characterized by style downward bending and mirror-image flowers, suggesting the style lateral bending in Gyrocheilos probably evolved from either of these conditions. In conclusion, the lateral bending style might provide landing platform for pollinators and the stigma above the lower lips increase contact probability the floral visitors, which is an adaptation to the very low insect visitation due to fragmented and foggy habitats in high altitude areas. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Computer Engineering & Applications is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to solve the bottleneck problem of radial expansion deformation of the rotor of grain peeling machine, the finite element model of the rotor was established according to the actual size of the rotor, the load characteristics of the rotor were studied, and the deformation distribution data of the longitudinal beam were fitted. First, two-step strategy optimization method and mirror symmetry method were used to compensate the structure of the model: the centrifugal load of the rotor was calculated, the range of pi, the safety factor and allowable stress range was determined. Then, the description function of longitudinal beam sweeping path was determine. Finally, the sensitivity analysis method was used to screen the parameters, and the central composite design method (CCD) was used to generate samples. The results shows that when p1 =1. 099 0 mm, p4 =3. 301 1 mm, p5 =4. 500 4 mm, p6 =3. 603 8 mm, p7 =2. 747 7 mm, p8 =2. 197 8 mm, the longitudinal beam has the best flatness and the highest safety factor. After compensation, the maximum stress of the rotor structure is reduced by 12. 89%, the maximum deformation is reduced by 11. 31%, the Str value has reduced by 64. 30%, and the safety factor is increased by 14. 78%. The mirror symmetry compensation technology is effective and feasible for solving the radial expansion deformation of the rotor of the peeling machine. [ABSTRACT FROM AUTHOR]