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21.
Khairul Salleh Hiroaki Seki Yoshitsugu Kamiya Masatoshi Hikizu 《Artificial Life and Robotics》2008,12(1-2):142-147
Manipulating deformable objects like clothes, plastic, and paper by a robot is very challenging. This paper focuses on clothes
manipulation as an example. A tracing manipulation method is used here to find a corner of the clothes. In this paper, tracing
refers to tracing the clothes’ edge, with the robot’s movement based on feedback from sensors. One difficulty during this
edge tracing is to make the robot trace smoothly and speedily without dropping the clothes in the process. This is due to
the fact that deformable objects are sensitive to contact forces. A solution to this problem is to design a special robot
gripper that can trace the clothes without having to worry about the clothes slipping away. In this paper, the development
of inchworm-type grippers is proposed. Two sets of grippers inside a robot hand will allow the robot to trace the clothes
more freely because there will always be a gripper firmly holding the clothes at any time. A unique tracing method for towel
spreading using the inchworm grippers is also discussed. Experimental results have demonstrated the effectiveness of both
the proposed grippers and also the algorithm.
This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January
25–27, 2007 相似文献
22.
Effect of heparin on high glucose induced proliferation and expression of matrix metalloproteinases in normal human mesangial cells 总被引:1,自引:0,他引:1
Zhou Qiao-ling Yasumoto Yuichiro Tsukamoto Masatoshi Nozaki Tsuyoshi Sogabe Atsushi Harada Kouji Zhang Yi-xiang Lin Xiao-yan Zhang Yang-de Arima Terukatsu 《中南工业大学学报(英文版)》2005,12(1):359-364
Background The pathogenesis of diabetic nephropathy (DN) is a complex pathophysiological process. Its precise mechanism is not fully
known. In recent years it has been recognized that synthesis of various extracelluar matrix (ECM) components may increase,
and that degradation of ECM may decrease in DN. It was reported heparin could inhibit mesangial cells proliferation in vitro.
The main aim of this study is to explore whether heparin inhibits proliferation of mesangial cells grown in high glucose concentration
and to measure the effect of heparin on matrix metalloproteinases (MMPs) expression in mesangial cells. Methods The medium contained either low glucose (5 mmol/L) or high glucose (25 mmol/L). The concentrations of heparin in the culture
medium were 0, 25, 50, 100, 200 or 400 μg/mL. A metabolic (WST-1) assay was used to measure mesangial cell proliferation and
Western blot analysis was used to measure MMPs expression of mesangial cells. Results Normal human mesangial cell (NHMC) proliferation was higher in high glucose (HG) medium than in low glucose (LG) medium.
They showed a 1.93 fold expansion after 72 h in high glucose in contrast to a 1.63 fold expansion in low glucose. In the presence
of heparin, mesangial cells proliferation was inhibited, which was more obvious at high glucose concentrations than at low
glucose concentrations. In high glucose, with heparin concentration of 50, 100, 200 and 400 μg/mL, the mesangial cells showed
a 0.61 fold, 0.52 fold, 0.52 fold and 0.41 fold reductions in cell number compared to cells grown without heparin. In low
glucose, only concentrations of 200 μg/mL and 400 μg/mL showed reduction in cell number, namely 0.54 fold and 0.45 fold, when
compared to cells grown without heparin. In Western blot analysis, MMP1, MMP2, MMP3 and MMP9 was expressed by mesangial cells expressed in both high and low glucose concentrations, which was more prominent in high
glucose medium. Incubation of heparin further increased expression of MMP1, MMP2, MMP3 and MMP9. Conclusions This study suggests that glucose can accelerate mesangial cell proliferation while heparin can reduce proliferation, being
more obvious at high glucose concentrations. Higher glucose concentrations led to increased MMP expression, which may take
part in the regulation of mesangial matrix synthesis and degradation. Addition of heparin resulted in a corresponding increase
in MMP expression, most notably at high glucose concentrations, indicating a potentially renoprotective role in DN.
Foundation item: Project (30370663) supported by the National Natural Science Foundation of China 相似文献
23.
It has been said that nuclear energy is an important option for especially developing countries to satisfy their increasing energy demand. However, it will be difficult to deploy first of a kind nuclear power plant in developing countries because extensive safety demonstration has to be conducted in industrialized countries. On the other hand, it will be essential to present rigid proof of reliable operational experience to develop proper understanding of the safety features of new reactor systems among the people around the demonstration plant sites. One of the ways to solve the issue is to integrate existing technologies supported by a great deal of data and experience into a new reactor design. Based on the consideration, a small-sized district heating reactor system based on the pressurized water reactor (PWR) technologies combined with the fuel concept of high temperature gas cooled reactors (HTGRs) has been studied. The purpose of the combination of these two existing concepts is to take the best advantages of both excellent operational experience of PWRs and the integrity of HTGR fuel, coated particle fuel, against fission products release even at high temperature. We expect that this approach will help create a breakthrough to the current stagnation of nuclear power deployment. 相似文献
24.
Koichi Uozumi Masatoshi Iizuka Tadashi Inoue Takashi Iwai 《Journal of Nuclear Materials》2004,325(1):34-43
Experiments were conducted on simultaneous recovery of uranium and plutonium electrochemically into laboratory scale liquid cadmium cathodes (LCCs) at different U/Pu ratios in the salt phase, and the influence of the salt composition on the recovered amounts of uranium and plutonium, the morphologies of uranium and plutonium in the LCC, and the behavior of americium, which is present as a decay product of plutonium-241, were examined. As a result, it was shown that there is a threshold in the U/Pu ratio in the salt phase between 1/4.3 and 1/1.73 for the successful simultaneous recovery of uranium and plutonium up to 10 wt% in the LCC at high current efficiencies. In the LCC, uranium and plutonium existed in the forms of intermetallic compounds, (U, Pu)Cd6 and (U, Pu)Cd11, and also pure uranium metal. It was also revealed that americium associates with plutonium according to the separation factor during the LCC operation. 相似文献
25.
Estimations have been made, resulting in a general method for the prediction of the incubation time for cavitation erosion using various cavitating conditions and materials. From a single erosion test, the incubation time can be estimated for various conditions and materials by plotting the mass loss as a function of exposure time to cavitation on a log–log scale. 相似文献
26.
27.
Masatoshi Hasegawa Masahito Horiuchi Kyoko Kumakura Junko Koyama 《Polymer International》2014,63(3):486-500
Alkyl‐substituted cyclobutanetetracarboxylic dianhydrides (CBDAs) were synthesized by photo‐dimerization of alkyl‐substituted maleic anhydrides to obtain novel colorless polyimides (PIs). Dimethyl‐substituted CBDA (DM‐CBDA) showed much higher polymerizability with various diamines than conventional cycloaliphatic tetracarboxylic dianhydrides and led to high molecular weights of PI precursors. Polyaddition of non‐substituted CBDA and trans‐1,4‐cyclohexanediamine (t‐CHDA) was completely inhibited by salt formation in the initial reaction stage. The use of DM‐CBDA allowed the formation of a homogeneous/viscous PI precursor solution by overcoming the salt formation problem. The prominent substituent effect probably reflects how the methyl substituents of DM‐CBDA contributed to increasing the salt solubility. Some of the thermally imidized DM‐CBDA‐based systems simultaneously possessed non‐coloration, low coefficient of thermal expansion (CTE), very high Tg exceeding 300 °C and very low dielectric constant. Copolymerization was very effective for improving the solubility of DM‐CBDA‐based PIs. The copolyimide cast films prepared via chemical imidization displayed a further decreased CTE without sacrificing other target properties, suggesting that the present materials can be useful as plastic substrates in display devices. The mechanism of self‐chain orientation behavior during solution casting is also discussed. A potential application of the copolyimide systems as optical compensation film materials in liquid crystal displays is proposed. © 2013 Society of Chemical Industry . 相似文献
28.
Yutaka Kawahara Atsushi Nakayama Masatoshi Shioya Masaki Tsuji Hideki Yamane Tadahisa Iwata 《Journal of Materials Science》2012,47(4):1887-1892
Structure of poly(dioxanone) (PPDX) fibers produced through a two-step melt-spinning process with an additional short-period
annealing above the melting temperature of PPDX was investigated and the effect of annealing on the degradation behavior was
discussed. The morphological study carried out by etching the fibers using a phosphate or permanganate solution suggested
that the fibers take a skin–core structure, and both the skin layer and the core region consist of a bundle of microfibrils.
The micro-beam X-ray diffraction analysis revealed that the short-period annealing in the production process only slightly
promotes the crystallization in the skin layer but contributes to increasing the packing of amorphous chains near the skin,
which seems to be the controlling factor of the hydrolytic degradation behavior of the fibers. 相似文献
29.
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