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61.
The lipid and fatty acid compositions in the various organs (muscle, liver, other viscera) and stomach contents of three common herbivorous fish species in Japan, Siganus fuscescens, Calotomus japonicus and Kyphosus bigibbus, were examined to explore the stable 20:4n-6 (arachidonic acid, ARA) sources. Triacylglycerol (TAG), phosphatidylethanolamine (PtdEtn), and phosphatidylcholine (PtdCho) were the dominant lipid classes, while the major FA contents were 16:0, 18:1n-9, 16:1n-7, 14:0, 18:0, 18:1n-7, and some PUFA, including ARA, 20:5n-3 (eicosapentaenoic acid, EPA), 22:5n-3 (docosapentaenoic acid, DPA), and 22:6n-3 (docosahexaenoic acid, DHA). The amounts of these fatty acids were varied among species and their lipid classes. Phospholipids contained higher levels of PUFA than TAG. However, ARA in both phospholipids and TAG was markedly present in the muscle and viscera of all specimens, particularly in C. japonicus and K. bigibbus. Moreover, their ARA levels were higher than the levels of DHA and EPA. The observed high ARA level is unusual in marine fish and might be characteristic of herbivorous fish. Furthermore, ARA was the dominant PUFA in the stomach contents of the three species, suggesting that the high ARA level originated from their food sources. The above indicates that these three herbivorous fishes are ARA-rich marine foods and have potential utilization as stable ARA resources.  相似文献   
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The dynamic mechanical properties and the adhesive strengths of epoxy resins-CTBN blend systems and epoxy resins-CTBNX blend systems were investigated. Both CTBN blend and CTBNX blend systems were proved to be partially compatible with the dynamic mechanical measurement. In the case of CTBN blend systems, the more blending of CTBN, the more the compatibility increased. On the other hand, CTBNX-20 was more compatible than CTBNX-30 but less than CTBNX-40. In any case, the blending of CTBN or CTBNX reduced the nonreacted part of the epoxy resins cured at room temperature. The adhesive strengths were evaluated as a function of the storage modulus with altering temperature and altering rubber content. Both procedures were proved to be equal.  相似文献   
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In all living systems, the genetic information is replicated by the self‐encoded replicase (Rep); this can be said to be a self‐encoding system. Recently, we constructed a self‐encoding system in liposomes as an artificial cell model, consisting of a reconstituted translation system and an RNA encoding the catalytic subunit of Qβ Rep and the RNA was replicated by the self‐encoded Rep produced by the translation reaction. In this system, both the ribosome (Rib) and Rep bind to the same RNA for translation and replication, respectively. Thus, there could be a dilemma: effective RNA replication requires high levels of Rep translation, but excessive translation in turn inhibits replication. Herein, we actually observed the competition between the Rib and Rep, and evaluated the effect for RNA replication by constructing a kinetic model that quantitatively explained the behavior of the self‐encoding system. Both the experimental and theoretical results consistently indicated that the balance between translation and replication is critical for an efficient self‐encoded system, and we determined the optimum balance.  相似文献   
67.
This study investigates the phenomenon of water freezing below the freezing point in polymer electrolyte fuel cell (PEFCs). Water generated on the surface of the catalyst layer was observed simultaneously with visible and infrared images. Surprisingly, it was found that water generated below the freezing point is in the liquid state and that the temperature rises to 0 °C at the time of freezing. It is generally known that heat of solidification is radiated when water in a super-cooled state starts to freeze. This study shows that water generated below the freezing point in polymer electrolyte fuel cells (PEFCs) is in a super-cooled state.  相似文献   
68.
Trypsin inhibitor from adzuki bean ( Vigna angularis ) seed was isolated and characterised. Extraction of seed with NaCl at the concentration of 0.15  m showed a higher recovery of trypsin inhibitor than other solvents tested ( P  <   0.05). Optimal extraction time for the recovery trypsin inhibitor from adzuki bean seed was 30 min ( P  <   0.05). Purification of inhibitor was achieved by heat-treatment at 90 °C for 10 min, followed by ammonium sulphate precipitation with 30–65% saturation and size exclusion chromatography on Sephacryl S-200, presenting a yield and purification of 53.9% and 10.91-fold, respectively. The apparent molecular weight of trypsin inhibitor was estimated to be 14 kDa based on SDS-PAGE and inhibitor activity of zones separated by electrophoresis. The purified inhibitor was stable over a broad pH range and retained high inhibitory activity toward trypsin after incubation at 90 °C for 60 min. NaCl, at 0–3% concentration, did not affect the inhibitory activity of purified trypsin inhibitor, however, the activity was lost when sample was treated with β-mercaptoethanol prior to electrophoresis.  相似文献   
69.
This paper discusses the correlation between peak spatial-average specific absorption rate (SAR) and maximum temperature increase for antennas attached to the human trunk. Frequency bands considered are 150, 400, and 900 MHz, which are assigned for occupational communications. This problem is throughly investigated with the aid of Green's function. In particular, the effect of variation of thermal constants on the temperature increase is revealed by using one-dimensional model. Computational results suggests that one of the most dominant factors which affect the correlation between peak SAR and maximum temperature increase is blood flow in tissues. This is confirmed by considering a three-dimensional realistic human body model. Uncertainties caused by the calculation of peak SAR and the difference in the body model shape are also quantified.  相似文献   
70.
Capacitive inclination sensors have the advantage that they can easily provide a linear analog output with respect to inclination. Although inclination sensors featuring this advantages are already commercially available, they are generally too large. We fabricated a micro-capacitive inclination sensor by a combination of a resin forming method and a mold. Electrodes of the sensor are 40 μm in a gap and 12 mm2 in area. The sensor detects difference of capacitance, which varies with movement of silicone oil accompanying with inclination of the sensor. Since the dimensions of the sensing region are 5 × 5 × 3 mm3 this inclination sensor is expected to be widely used in fields where efficient and reliable position control is a primary factor to be considered. The use of resins is also expected to contribute to a reduction in the costs of materials. We successfully fabricated a micro inclination sensor as a molded product. In future, we will wire up the device to complete this inclination sensor, and will then conduct performance evaluations. If techniques using resin-molded parts are introduced to the low-cost mass-production of Micro Electro Mechanical Systems devices, the range of applications will further expand to new areas of technology and industry.  相似文献   
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