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801.
Roger S. Porter James M. Jonza Masao Kimura C. Richard Desper Eric R. George 《Polymer Engineering and Science》1989,29(1):55-62
Thermal and mechanical studies on many linear polyesters have revealed their behavior in crystalline, liquid crystalline, and amorphous phases. Their phase behavior in binary compositions has also been studied by a range of additional techniques and in combinations including the polycarbonate of bisphenol-A. Regions of amorphous compatibility and incompatibility have been identified and measures made of transition temperature changes with composition. The conditions for transreaction have also been determined and the properties measured for the resultant new copolymers. 相似文献
802.
803.
T Kimura Y Ito A Einspanier K Tohya T Nobunaga Y Tokugawa M Takemura Y Kubota R Ivell N Matsuura F Saji Y Murata 《Canadian Metallurgical Quarterly》1998,13(9):2645-2653
The milk ejection reflex is mediated by the release of pituitary oxytocin and its interaction with specific receptors within the mammary gland. Although up-regulation of the oxytocin receptor during lactation has been shown for the rat mammary gland by ligand binding assay, investigation of the receptor expression in human breast at the molecular level has not yet been carried out in detail. Here we report the expression and immunolocalization of the oxytocin receptor in the human breast. It appears that the expression level of the receptor-specific mRNA is not significantly elevated during lactation and the protein remains at a relatively low level. However, this lack of increase may be only a dilution effect because of the high level of milk protein expression. Immunohistochemistry and immunoelectron microscopy using three anti-oxytocin receptor antibodies raised against different epitopes of the receptor indicated the presence of receptor immunoreactivity only to a very limited extent in the myoepithelial cells; more specific expression appeared to occur in the ductal/glandular epithelium in both the non-lactating as well as lactating breast. This finding was also confirmed in a New World monkey, the common marmoset (Callithrix jacchus). These results suggest that, at least for human and marmoset, in addition to--or even instead of--myoid cells, the ductal/glandular epithelium is also a target for oxytocin action, not only during lactation but also in the non-lactating breast. Thus, there may be other physiological effects of oxytocin besides direct myoid cell contraction in the breast. 相似文献
804.
805.
806.
Guoqiang Xie Dmitri V. Louzguine-Luzgin Li Song Hisamichi Kimura Akihisa Inoue 《Intermetallics》2009,17(7):512-516
Two-phase bulk metallic glasses (BMGs) have attracted increasing interest since phase separation might produce metallic glasses with new physical and mechanical properties. In this study, we fabricated the dual phase glassy BMG composites by a spark plasma sintering process using a mixed powder of the gas-atomized Ni-based and Fe-based metallic glassy alloy powders. The thermal stability, microstructure, mechanical and magnetic properties of the obtained dual-phase glassy composites were investigated. The dual-phase glassy composites exhibited ultra-high strength and good soft magnetic properties which satisfy large-size requirements. 相似文献
807.
Ogawara K. Takamatsu J. Kimura H. Ikeuchi K. 《Industrial Electronics, IEEE Transactions on》2003,50(4):667-675
This paper describes a new approach on how to teach a robot everyday manipulation tasks under the "Learning from Observation" framework. In this approach, human demonstrations, which are made up of mutual interactions between a grasped object and an environmental object, are observed and a reusable manipulation task model is automatically generated. Most of the similar approaches so far assume that a demonstration can be well understood from a single demonstration. However, a single demonstration contains ambiguity, in that interactions which are essential to complete a task cannot be discerned without prior task dependent knowledge, which should be obtained from observation. To address these issues, a technique to integrate multiple observations of demonstrations is proposed. The demonstrations differ, but are virtually the same task. The shared interactions among all the demonstrations are considered to be essential and a task model is generated from their symbolic representations. Then, the relative trajectories corresponding to each essential interaction are generalized by calculating their mean and variance, and they are also stored in the task model, which is used to reproduce skilled behavior. This approach is examined by using a human-form robot, which successfully imitates human demonstrations of everyday tasks. 相似文献
808.
Cellular proteins of a normal human diploid fibroblast line (TIG-3) at various stages of replicative aging were resolved by horizontal isoelectric focusing on an immobilized pH gradient, followed by vertical sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE). Spot proteins were visualized by silver staining and quantitated by image processing. All corresponding spots were matched among two-dimensional gel images, and variation profiles in relative abundance of individual proteins during in vitro aging were classified into five categories, i.e., (i) increase, (ii) decrease, (iii) increase followed by decrease, (iv) decrease followed by increase, and (v) irregular or nonsignificant variation. The new concept of the Tokyo Metropolitan Institute of Gerontology two-dimensional gel protein database (TMIG-2DPAGE) was prepared from the above data to support research on cellular aging. The database was put on our World Wide Web home page at the URL of http://www.tmig.or.jp/2D/ to allow free access through the Internet. The individual protein data entries were linked to the standard spot protein map of the two-dimensional gel image in order to be accessible by clicking the mouse on it. 相似文献
809.
Purkinje cells of the cerebellum discharge complex spikes, named after the complexity of their waveforms, with a frequency of approximately 1 Hz during arm movements. Despite the low frequency of firing, complex spikes have been proposed to contribute to the initiation of arm movements or to the gradual improvement of motor skills. Here we recorded the activity of Purkinje cells from the hemisphere of cerebellar lobules IV-VI while trained monkeys made short-lasting reaching movements (of approximately 200 milliseconds in duration) to touch a visual target that appeared at a random location on a tangent screen. We examined the relationship between complex-spike discharges and the absolute touch position, and between complex-spike discharges and relative errors in touching the screen. We used information theory to show that the complex spikes occurring at the beginning of the reach movement encode the absolute destination of the reach, and the complex spikes occurring at the end of the short-lasting movements encode the relative errors. Thus, complex spikes convey multiple types of information, consistent with the idea that they contribute both to the generation of movements and to the gradual, long-term improvement of these movements. 相似文献
810.
The effect of addition of 0.25 pct silicon and aluminum on the intergranular fracture and the grain-boundary segregation of
solutes in a high-purity Fe-0.2 pct P alloy with a trace of boron has been investigated by impact test, tensile test at low
temperatures, optical and scanning electron microscopy, and Auger electron spectroscopy (AES). The addition of 0.25 pct silicon
and aluminum remarkably reduces the susceptibility of an Fe-0.2 pct P alloy to the intergranular fracture and decreases the
ductile-brittle transition temperature (DBTT). The addition of silicon and aluminum causes considerable segregation of boron
to grain boundaries and, simulta-neously, remarkably decreases the segregation of phosphorus in the Fe-0.2 pct P alloy. The
cause for these effects is discussed.
Formerly Professor, Institute for Materials Research, Tohoku University 相似文献