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1.
In Caenorhabditis elegans, the vulval induction is mediated by tyrosine kinase receptor/Ras signal transduction pathway composed of the lin-3, let-23, and let-60 products. In addition to these gene products, the lin-2, lin-7, and lin-10 products are also implicated in this pathway. Lin-2 encodes a MAGUK and lin-7 encodes a small protein with one PDZ domain. The lin-10 product has no homology to known proteins. Here, we have cloned a rat homologue of the lin-10 product and characterized it. Rat lin-10 is ubiquitously expressed in various rat tissues and distributed in both the cytosol and membrane fractions. In brain, however, rat lin-10 is distributed only in the membrane fraction and enriched in the synaptic plasma membrane and postsynaptic density fractions. These results suggest that rat lin-10 is involved at least in synaptic functions in brain.  相似文献   
2.
The role of ergosterol in yeast stress tolerance, together with heat shock proteins (hsps) and trehalose, was examined in a sterol auxotrophic mutant of Saccharomyces cerevisiae. Ergosterol levels paralleled viability data, with cells containing higher levels of the sterol exhibiting greater tolerances to heat and ethanol. Although the mutant synthesised hsps and accumulated trehalose upon heat shock to the same levels as the wild-type cells, these parameters did not relate to stress tolerance. These results indicate that the role of ergosterol in stress tolerance is independent of hsps or trehalose.  相似文献   
3.
This paper overviews the International Standards Organization–Linguistic Annotation Framework (ISO–LAF) developed in ISO TC37 SC4. We describe the XML serialization of ISO–LAF, the Graph Annotation Format (GrAF) and discuss the rationale behind the various decisions that were made in determining the standard. We describe the structure of the GrAF headers in detail and provide multiple examples of GrAF representation for text and multi-media. Finally, we discuss the next steps for standardization of interchange formats for linguistic annotations.  相似文献   
4.
Some mechanical properties of styrene and acrylonitrile copolymers grafted onto acrylic rubber are investigated. The impact strength of graft polymers depended upon the nature and the concentration of the catalyst, the composition and the intrinsic viscosity of the rubber, and the acrylonitrile content in the rigid matrix. The most desirable result was obtained when benzoyl peroxide as the catalyst, n-butyl acrylate–acrylonitrile copolymer of 7–10% acrylonitrile content, and about 0–5% acrylonitrile in the rigid matrix were used. Dynamic mechanical tests show the increase in efficiency of rubber modification by the grafted chains. The better weathering resistance of these graft polymers, as compared with commercial ABS plastics, was confirmed.  相似文献   
5.
An asymmetric double cantilever beam test was used to determine the ability of carbon nanotubes with varying chemistry along their lengths, that is, diblock nanotubes, to compatibilize the polystyrene/poly(methyl methacrylate) (PS/PMMA) interface. PS molecules were grafted primarily to one of the blocks to cause that block to migrate to the PS phase since otherwise both blocks would prefer to reside in PMMA. Fracture toughnesses increased monotonically with increasing diblock carbon nanotube concentration and maximum values were like those for block copolymer-reinforced interfaces while single-chemistry nanotubes showed no reinforcing effect. However, the abrupt increase in fracture toughness with added compatibilizer indicative of a transition to crazing was not found consistent with nanotubes suppressing crazing in homopolymers. Scanning electron microscopy images of the fractured surfaces show agglomerates of carbon nanotubes present which are likely limiting the efficacy of carbon nanotubes at toughening the interface.  相似文献   
6.
The use of an agent in the environment, as in medical treatment, welfare, the construction field, and the home, is examined. It is necessary for the agent to be able to work cooperatively with a human, and that may be a problem. Therefore, this study pays attention to the phenomenon that is called entrainment. This is the phenomenon where the rhythm of a certain person and the partner in the communication is synchronized. The purpose of this study is to perform a basic examination into applying an entrainment in order to realize cooperation in operations between a human and an agent. Since many human rhythms are expressed by a nonlinear oscillator, we simulated limited cycle oscillators, which are one of two nonlinear oscillators that cause interactions between agents, as the basic examination for this achievement. Consequently, entrainment of limited cycle oscillators with rhythms which differ has been checked in certain conditions. As a result, the possibility that cooperative movement could be gained was suggested.  相似文献   
7.
This paper describes relationships between characteristics of a magnetically anisotropic slot wedge and voltage higher harmonics in an ac exciting synchronous generator terminal due to permeance ripple caused by an open-slot-type rotor. From the relationships obtained, practical guidelines were formulated for machine designs applying the magnetically anisotropic slot wedge. The results are as follows.
  • 1 (1) Equivalent permeability of the magnetically anisotropic slot wedge became isotropic wedge permeability for air-gap flux ripple.
  • 2 (2) Two ways were identified to reduce voltage-higher harmonics by using the slot wedges.
  • 3 (3) The level of leakage flux passing through the anisotropic slot wedge was determined only by its permeability in the width direction.
  • 4 (4) Effectiveness of the magnetic anisotropic slot wedges inserted into the stator slots was verified from experimental results using a model machine of the open- slot-type rotor.
  相似文献   
8.
We propose a recognition method of character-string images captured by portable digital cameras. A challenging task in character-string recognition is the segmentation of characters. In the proposed method, a hypothesis graph is used for recognition-based segmentation of the character-string images. The hypothesis graph is constructed by the subspace method, using eigenvectors as conditionally elastic templates. To obtain these templates, a generation-based approach is introduced in the training stage. Various templates are generated to cope with low-resolution. We have experimentally proved that the proposed scheme achieves high recognition performance even for low-resolution character-string images. The text was submitted by the authors in English. Hiroyuki Ishida. Received his B.S. and M.S. degrees from the Department of Information Engineering and from the Graduate School of Information Science, respectively, at Nagoya University. He is currently pursuing a Ph.D. in Information Science at Nagoya University. Ichiro Ide. Received his B.S. degree from the Department of Electronic Engineering, his M.S. degree from the Department of Information Engineering, and his Ph.D. from the Department of Electrical Engineering at the University of Tokyo. He is currently an Associate Professor in the Graduate School of Information Science at Nagoya University. Tomokazu Takahashi. Received his B.S. degree from the Department of Information Engineering at Ibaraki University, and his M.S. and Ph.D. from the Graduate School of Science and Engineering at Ibaraki University. His research interests include computer graphics and image recognition. Hiroshi Murase. Received his B.S., M.S., and Ph.D. degrees from the Graduate School of Electrical Engineering at Nagoya University. He is currently a Professor in the Graduate School of Information Science at Nagoya University. He received the Ministry Award from the Ministry of Education, Culture, Sports, Science and Technology in Japan in 2003. He is a Fellow of the IEEE.  相似文献   
9.
Our purpose is to develop the technology for evaluating emotion objectively from the oxygenated hemoglobin within a brain. Nowadays, Japan is an aging society. The elderly people who need care will increase from now on increasingly. In the case of the person requiring the care who lost the function to convey an intention especially, the objective judgment to a physical and mental pain is required. Persons requiring care will also increase in number with the increase in this population. We gave subject stimulus of a comfortable or an uncomfortable sound and measured concentration of the oxygenated hemoglobin of a frontal lobe part by near-infrared spectroscopy. Based on the experimental result, a comfortable state or an uncomfortable state was distinguished by concentration of the oxygenated hemoglobin using the bayesian network. As a result, we were able to estimate the subject’s psychological condition.  相似文献   
10.
The effect of the type of dietary fiber on the bile acid and taurine metabolism was examined in rats. Diets containing 10% of various water-soluble fibers (citrus pectin, konjak mannan, guar gum) as compared to a fiber-free diet increased biliary excretion of total bile acids. In contrast, water-insoluble dietary fibers (cellulose, corn bran, chitin; 10% in the diets) as well as cholestyramine (5% in the diet) considerably, decreased bile acid excretion. Water-soluble dietary fibermediated increases in bile acid excretion were totally attributable to increases in glycine-conjugates. Thus, these fibers greatly increased by the bile acid glycine-to-taurine ratio (G/T). Excretio of glycine conjugates decreased more than that of taurine conjugates in rats fed various water-insoluble dietary fibers. As a results, G/T in rats fed water-insoluble fibers was significantly lowered as compared to G/T in animals fed a fiber-free diet. Cholestyramine did not affect the G/T ratio of bile acids. Fecal bile acid excretion and the activities of hepatic cholesterol 7α-hydroxylase (EC 1.14.13.17) in rats fed various water-soluble dietary fibers approximately doubled as compared to the respective values for rats fed a fiber-free diet. Whereas cholestyramine greatly increased these parameters, water-insoluble fibers did not significantly affect them. Various water-soluble fibers decreased hepatic concentration and urinary excretion of taurine as well as the activity of hepatic cysteine dioxygenase (EC 1.13.11.20). In contrast, water-insoluble fibers considerably increased hepatic taurine concentrations and enzyme activities. The parameters for taurine metabolism were unaffected by cholestyramine. It was suggested that the types of dietary fiber affected hepatic taurine synthesis and thus modified bile acid glycine/taurine ratios.  相似文献   
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