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91.
Yamada Jun-Ichi Temmyo Jiro Yoshikawa Shokichiro Kimura Tatsuya 《Electronics letters》1980,16(2):57-58
The performance of a 1.6 Gbit/s optical receiver employing a s.a.w. filter as a timing tank is reported. The error-rate characteristics in a p.c.m. transmission system using a 1.3 ?m In-GaAsP laser and single-mode fibres were studied. The average received optical power at a 10?9 error rate was ?28 dBm. In a 15 km transmission experiment, the receiving level was degraded by 2 dB owing to fibre dispersion. Timing phase margin of 75 degrees after 12 km transmission was confined with the self-timed receiver. 相似文献
92.
Magnetic properties of CeC2 and its solid solutions, CeXDy1?XC2, were investigated. Cerium dicarbide has the highest Neel temperature, 30 K, of the cerium compounds with non-magnetic elements and a positive paramagnetic Curie temperature, +12 K. This Nèel temperature is greatly higher than that expected on the basis of the de Gennes factor. In order to explain this high Nèel temperature we propose an idea that a super exchange interaction via acetylide ion, C22?, contributes much to the total magnetic exchange for CeC2. The positive paramagnetic Curie temperature observed for CeC2 are also discussed in terms of the crystal field effects. The Nèel temperature (TN) for CeXDy1?XC2 has a minimum on the TN vs. the de Gennes factor curve, while the paramagnetic Curie temperature (θp) varies almost linearly with the de Gennes factor. These behaviors of TN and θp are understood based on a difference in the magnetic exchange between CeC2 and DyC2. 相似文献
93.
Summary Viscometry of PLGNa solutions was performed for various degrees of neutralization . The cooperativity parameter in the helix-coil transition was estimated using Ptitsyn's method with some modifications. The increase of thus obtained with decreasing is explained in terms of the a dependence of short-range interactions of PLGNa segments. 相似文献
94.
Cvacka J Kofronová E Vasícková S Stránský K Jiros P Hovorka O Kindl J Valterová I 《Lipids》2008,43(5):441-450
Unusual fatty acids with 24, 26, and 28 carbon atoms were found in triacylglycerols (TAGs) isolated from fat body tissue of
bumblebee Bombus pratorum. The most abundant one was (Z,Z)-9,19-hexacosadienoic acid. Its structure was determined by mass spectrometry after derivatization with dimethyl disulfide
and by infrared spectroscopy. ECL (equivalent chain length) values of its methyl ester were determined on both DB-1 and DB-WAX
capillary columns. (Z,Z)-9,19-Hexacosadienoic acid is quite rare in nature. So far it has been identified only in marine sponges, and this work is
the first evidence of its occurrence in a terrestrial organism. HPLC/MS analysis of the bumblebee TAGs showed that (Z,Z)-9,19-hexacosadienoic acid is present in one third of all TAG molecular species. As it was found in all sn-TAG positions,
it is likely that (Z,Z)-9,19-hexacosadienoic acid is transported to tissues. Interestingly, labial gland secretion of B. pratorum was found to contain (Z,Z)-7,17-pentacosadiene, a hydrocarbon with markedly similar double bond positions and geometry. Possible biosynthetic relationships
between these two compounds are discussed. 相似文献
95.
96.
RH Perez K Himeno N Ishibashi Y Masuda T Zendo K Fujita P Wilaipun V Leelawatcharamas J Nakayama K Sonomoto 《Journal of Bioscience and Bioengineering》2012,114(5):490-496
Enterococcus faecium NKR-5-3 produces four antimicrobial peptides referred here as enterocins NKR-5-3A, B, C and D. A two-step electrospray ionization-liquid chromatography and mass spectrometry (ESI-LC/MS)-based quantification system was developed to monitor its multiple bacteriocin production profiles, which is essential in understanding the complex production regulation mechanism of strain NKR-5-3. The developed ESI-LC/MS-based quantification system can easily monitor the multiple bacteriocin production of this strain. Using the developed system, the production of enterocin NKR-5-3B was found to be not as variable as those of the other enterocins in different cultivation media. Production of enterocin NKR-5-3B was also found to have a wider optimum incubation temperature (20-30°C) than enterocins NKR-5-3A, C and D (25°C). Furthermore, at least 2?nM of the bacteriocin-like inducing peptide, enterocin NKR-5-3D, regulated the production of NKR-5-3 enterocins except enterocin NKR-5-3B. These findings taken together suggest that enterocin NKR-5-3B has an independent production regulation mechanism from the other NKR-5-3 enterocins. The developed system could effectively pin-point the production profiles of the multiple bacteriocins of E.?faecium NKR-5-3 under different fermentation conditions. 相似文献
97.
Tadashi Hatanaka Yosikazu Inoue Jiro Arima Yuya Kumagai Hirokazu Usuki Kayoko Kawakami Masayo Kimura Takafumi Mukaihara 《Food chemistry》2012
The insulinotropic hormone glucagon-like peptide-1 is metabolised extremely rapidly by the ubiquitous enzyme dipeptidyl peptidase IV (DPP-IV). Therefore, human DPP-IV is a key regulator involved in the prevention and treatment of type 2 diabetes. To simplify the method of producing an inhibitory peptide against DPP-IV, we focused on rice bran (RB) as a source and subjected proteins from defatted RB to enzymatic proteolysis using 2 commercial enzymes. The RB peptides produced with Umamizyme G exhibited 10 times the inhibitory activity as those produced with Bioprase SP. The half-maximal inhibitory concentration (IC50) value of the RB peptides was 2.3 ± 0.1 mg/ml. Leu-Pro and Ile-Pro were identified as the inhibitory peptides among the RB peptides produced with Umamizyme G. Ile-Pro was the strongest DPP-IV inhibitor among the 15 Xaa-Pro dipeptides and Pro-Ile tested. Ile-Pro competitively inhibited DPP-IV (Ki = 0.11 mM). Mass spectrometry indicated that the contents of Leu-Pro and Ile-Pro in the RB peptides were 2.91 ± 0.52 μg/mg. 相似文献
98.
Satoshi Inoue Jiro Takito Masanori Nakamura 《International journal of molecular sciences》2021,22(17)
The process of fracture healing varies depending upon internal and external factors, such as the fracture site, mode of injury, and mechanical environment. This review focuses on site-specific fracture healing, particularly diaphyseal and metaphyseal healing in mouse long bones. Diaphyseal fractures heal by forming the periosteal and medullary callus, whereas metaphyseal fractures heal by forming the medullary callus. Bone healing in ovariectomized mice is accompanied by a decrease in the medullary callus formation both in the diaphysis and metaphysis. Administration of estrogen after fracture significantly recovers the decrease in diaphyseal healing but fails to recover the metaphyseal healing. Thus, the two bones show different osteogenic potentials after fracture in ovariectomized mice. This difference may be attributed to the heterogeneity of the skeletal stem cells (SSCs)/osteoblast progenitors of the two bones. The Hox genes that specify the patterning of the mammalian skeleton during embryogenesis are upregulated during the diaphyseal healing. Hox genes positively regulate the differentiation of osteoblasts from SSCs in vitro. During bone grafting, the SSCs in the donor’s bone express Hox with adaptability in the heterologous bone. These novel functions of the Hox genes are discussed herein with reference to the site-specificity of fracture healing. 相似文献
99.
Jiro Yates 《Journal of Architectural Education》2013,67(4):252-262
A work of architecture is experienced at many different levels, and yet all too often, preconceived notions of style and form at the largest scale are generated initially and become the operative focus of a given project. Carefully considered moments and rich tactile articulation on a human scale are all but lost to image-oriented design that glorifies the building as an object. It is the design of these component elements and the methodology according to which they are constructed and integrated into the whole that interest me. I believe that alternative design methodologies that analyze the role and function of the detail must be explored and elaborated. 相似文献
100.
An analogue voltage-voltage convertor circuit using l.e.d-CdSe photoresistors and several active elements is proposed. The error in a transfer characteristic were less than 1% in the compensated experimental circuit. 相似文献