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21.
The determination of conjugated diene formation revealed that the mol % conversions of allcis-6,9,12-octadecatrienoic acid [γ-linolenic, 18:3(n-6)], allcis-5,8,11,14-eicosatetraenoic acid [arachidonic, 20:4(n-6)], allcis-5,8,11,14,17-eicosapentaenoic acid [20:5(n-3)], and allcis-4,7,10,13,16,19-docosahexaenoic acid [22:6(n-3)] into conjugated diene products by soybean lipoxygenase-1 at pH 9.0 were 84, 86, 60 and 40% of that of allcis-9,12-octadecadienoic acid [linoleic, 18:2(n-6)], respectively. On the other hand, the conversions of allcis-9,12,15-octadecatrienoic acid [α-linolenic, 18:3(n-3)], allcis-5,9,12-octadecatrienoic acid (c5,c9,c12-18:3), andtrans-5,cis-9,cis-12-octadecatrienoic acid (t5,c9,c12-18:3) were equal to that of 18:2(n-6). The lowering of the conjugated diene formation in the oxidation of 18:3(n-6), 20:4(n-6), 20:5(n-3), and 22:6(n-3) by the lipoxygenase was thought to be caused by the further oxidation of conjugated diene monohydroperoxides to yield conjugated triene products. For this reason, the conventional lipoxygenase method gave erroneous values forcis,cis-methylene interrupted polyunsaturated fatty acids (PUFA) in oils containing a large amount of 20:5(n-3) and 22:6(n-3) such as fish oils. However, by changing the pH of reaction mixtures from 9.0 to 11.0, the secondary oxidation of conjugated diene monohydroperoxides was completely inhibited, and the PUFA values in fish oils obtained by this improved method were in good agreement with those obtained by a GLC method.  相似文献   
22.
Cross‐linked polyethylene (XLPE) has been widely adopted as insulating material for high‐voltage power cables up to 500 kV. Further improvement of electrical and thermal properties on insulating material is required in order to increase cable operation efficiency. Therefore, the development of novel insulating material possessing high thermal properties will be necessary. Recent progress of catalysis technology contributes to obtain new polymeric materials which may be applied to electrical insulation. The authors investigated the basic properties of newly developed stereoregular syndiotactic polypropylene (s‐PP) which is synthesized with homogeneous metallocene catalyst. Though recycling of cross‐linked polymers such as conventionally used XLPE may be difficult because of their poor heat deformation, the s‐PP which is not cross‐linked must be suitable for recycling. A series of experiments on its physical and electrical properties gave the following results.
  • (1) s‐PP has sufficient flexibility compared with isotactic polypropylene (i‐PP ).
  • (2) Both AC and lightning impulse breakdown strength of s‐PP in spite of no cross‐linking are superior to those of XLPE in the temperature range from 25 to 90 °C.
  • (3) Degradation by copper of s‐PP is less than that of i‐PP.
  • (4) s‐PP/VLDPE blend shows sufficient brittleness temperature for use.
These results suggested that s‐PP should serve as insulating material for power cables at higher‐temperature operation. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 146(1): 18–26, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002//eej.10210  相似文献   
23.
Chemokines secreted from stromal cells have important roles for interactions with carcinoma cells and regulating tumor progression. C-C motif chemokine ligand (CCL) 5 is expressed in various types of stromal cells and associated with tumor progression, interacting with C-C chemokine receptor (CCR) 1, 3 and 5 expressed in tumor cells. However, the expression on CCL5 and its receptors have so far not been well-examined in human breast carcinoma tissues. We therefore immunolocalized CCL5, as well as CCR1, 3 and 5, in 111 human breast carcinoma tissues and correlated them with clinicopathological characteristics. Stromal CCL5 immunoreactivity was significantly correlated with the aggressive phenotype of breast carcinomas. Importantly, this tendency was observed especially in the CCR3-positive group. Furthermore, the risk of recurrence was significantly higher in the patients with breast carcinomas positive for CCL5 and CCR3 but negative for CCR1 and CCR5, as compared with other patients. In summary, the CCL5-CCR3 axis might contribute to a worse prognosis in breast cancer patients, and these findings will contribute to a better understanding of the significance of the CCL5/CCRs axis in breast carcinoma microenvironment.  相似文献   
24.
Abstract— Quick, stable transition from splay‐to‐bend alignment in optically compensated bend (OCB) mode is crucial for practical use. This has been achieved by surface treating part of a pixel with a chiral dopant to induce a twist alignment while controlling the twist direction. The effectiveness of this new method was confirmed in a prototype TFT‐LCD panel.  相似文献   
25.
The latest developments in light‐emitting‐polymer (LEP) technology at CDT continue to show steady progress. Device performance for blue, green, and red systems as well as a high‐performance yellow system in terms of device efficiency and stability will be described. Some of the issues associated with the commercialization of LEP technology including the development of direct‐patterning techniques enabling full‐color passive‐ and active‐matrix display will be discussed.  相似文献   
26.
Abstract— The adsorption strength of liquid‐crystal molecules on the alignment‐layer (polymer) surface was judged measuring temperature dependence of birefringence of an absorbed liquid‐crystal layer above the nematic—isotropic transition temperature. The relationship between the surface‐order parameter and the adsorption strength of liquid‐crystal molecules on the non‐rubbed polymer surface was also discussed.  相似文献   
27.
Abstract— One problem with front‐projection displays is that the screen contrast ratio decreases in bright ambient light. In this paper, we propose a new front‐projection display system that incorporates the control of reflection of ambient light in the screen design, providing a high contrast ratio even in a brightly lit room.  相似文献   
28.
This article demonstrates the self-replication and self-organization phenomena based on a reaction–diffusion mechanism by computer simulation. The simulation model consists of a one-dimensional cell array. Each cell contains two kinds of chemical substances, activator u and inhibitor v, that can generate a reaction–diffusion wave, which is a spatial concentration pattern. The cells are supposed to be divided or deleted depending on the concentrations of chemical substances. We tried several kinds of diffusion coefficient in the model, and in some simulations, a self-replication process and a generating cell array with a metabolic process were observed. By applying the division rule and the apoptosis rule, cell arrays duplicate in two oscillating states, i.e., self-replication processes were observed. By applying a division rule and an annihilation rule, a cell array that has a stable length is generated by changing the cell components, i.e., generating a cell array by a metabolic process was observed. Surprisingly, these two phenomena are realized independently of the initial number of cells. This work was presented in part at the 11th International Symposium on Artificial Life and Robotics, Oita, Japan, January 23–25, 2006  相似文献   
29.
Identifying the extent to which the appearance of a humanoid robot affects human behavior toward it is important. We compared participant impressions of and behaviors toward two real humanoid robots in simple human-robot interactions. These two robots, which have different appearances but are controlled to perform the same recorded utterances and motions, are adjusted by a motion-capturing system. We conducted an experiment with 48 human participants who individually interacted with the two robots and also with a human for reference. The results revealed that different appearances did not affect participant verbal behaviors, but they did affect such nonverbal behaviors as distance and delay of response. These differences are explained by two factors: impressions and attributions.  相似文献   
30.
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