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81.
We report electrical manipulation of magnetization processes in a ferromagnetic semiconductor, in which low-density carriers are responsible for the ferromagnetic interaction. The coercive force HC at which magnetization reversal occurs can be manipulated by modifying the carrier density through application of electric fields in a gated structure. Electrically assisted magnetization reversal, as well as electrical demagnetization, has been demonstrated through the effect. This electrical manipulation offers a functionality not previously accessible in magnetic materials and may become useful for reversing magnetization of nanoscale bits for ultrahigh-density information storage. 相似文献
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Le-Chang Sun Kodai Kaneko Emiko Okazaki Min-Jie Cao Hiroki Ohwaki Wu-Yin Weng Kazufumi Osako 《Fisheries Science》2013,79(3):537-546
North Pacific krill is widely distributed in the waters around Japan, however its utilization for human consumption has been limited due to its small size. We have investigated the proximate composition, the amino acid, free fatty acid, mineral and protein composition, respectively, as well as the residual proteolytic activity of krill protein, as recovered by acidic- and alkaline-aided isoelectric solubilization/precipitation, in order to facilitate effective utilization of this krill species. Krill protein yield was 31.7 and 73.4 % by acidic and alkaline treatment, respectively. Both treatments resulted in a comparable higher content of essential amino acids than that in whole krill, accompanied with effective removal of insoluble materials. Three major proteolytic active bands with molecular weights of approximately 28, 18 and 16 kDa, as estimated by gelatin-based zymography, were detected. Pronounced residual proteolytic activity was observed in the krill protein after alkaline processing, implying the possible involvement of proteinase(s) in protein degradation during alkaline solubilization. Based on these results, we suggest that inhibition of proteolysis during isoelectric solubilization/precipitation is required for the effective use of North Pacific krill. 相似文献
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The present study evaluated the quality of setting gels prepared by adding sodium acetate, sodium gluconate, sodium citrate,
and sodium succinate to Todarodes pacificus mantle muscle meat, and of the acid-induced kamaboko gels produced by soaking the setting gels in their corresponding acid
solutions. The breaking strength was the lowest for the setting gel treated with sodium acetate. The pH values of the acid-induced
kamaboko gels decreased when soaked in acid, whereas their moisture contents, whitenesses, and breaking strengths increased.
The citric acid-induced kamaboko gel had the highest whiteness index and breaking strength among the gels. The sodium dodecyl
sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) patterns did not show large differences among the gels, except for a
low-intensity polymer band in the gluconic acid-induced kamaboko gel. Sodium citrate combined with citric acid yielded the
best-quality acid-induced kamaboko gel among all the combinations, so this condition was used to study the effect of organic
salt levels. The breaking strength increased when a sodium citrate level of up to 3% was used for the sodium citrate-treated
setting gel, and 10% for the citric acid-induced kamaboko gel. The SDS-PAGE patterns did not differ among the sodium citrate
levels. Egg white and microbial transglutaminase were necessary for citric acid-induced kamaboko gel production. 相似文献
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Shinichi WATANABE Megumi MIURA Hiromi MORITA Moeka NISHI Shin-ichi YOKOTA Shosaku HATTORI Hiromichi MATSUMOTO Emiko FUKUI Ken Takeshi KUSAKABE Masanori OCHI Naomi NAKAGATA Yasuo KISO Chieko KAI Midori YOSHIZAWA 《The Journal of reproduction and development》2021,67(4):265
Advanced reproductive technologies are being applied for the propagation of squirrel monkeys, to ensure their preservation as a genetic resource and the effective use of their gametes in the future. In the present study, oocytes and spermatozoa were collected from live squirrel monkeys, following which piezo intracytoplasmic sperm injection (ICSI) was performed using these gametes. Follicular development was induced by administering equine chorionic gonadotropin (eCG) containing inhibin antiserum to an immature squirrel monkey female. The unilateral ovary was excised after the administration of human chorionic gonadotropin (hCG), to induce ovulation, following which the larger developed follicular oocytes were collected. Follicular oocytes were prepared for ICSI using sperm from the epididymal tail of a unilateral testis extracted from a mature male. The embryos were continuously incubated in CMRL 1066 medium supplemented with 10% (v/v) fetal bovine serum. Embryo culture was performed with cumulus cells. Two experiments of ICSI carried out with three females resulted in 14 mature oocytes from the 49 cumulus-oocyte complexes collected and five embryos, three of which developed into blastocysts. These blastocysts were vitrified, thawed, and transferred to recipient monkeys, but no pregnancies resulted. In conclusion, the present study is the first to successfully produce ICSI-derived blastocysts from MII oocytes obtained by means of hormone administration (a combination of eCG+inhibin antiserum and hCG) and in vitro maturation in immature squirrel monkeys. 相似文献
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Hiroe YoshidaTakeshi Horie Kou NakazonoHiroyuki Ohno Hiroshi Nakagawa 《Field Crops Research》2011,124(3):433-440
The objective of this study was to identify physiological processes that result in genotypic and N fertilization effects on rice yield response to elevated atmospheric CO2 concentrations ([CO2]). This study conducted growth and yield simulations for 9 rice genotypes grown at 4 climatically different sites in Asia, assuming the current atmospheric [CO2] (360 ppm) and elevated [CO2] (700 ppm) using 5 levels of N fertilizer (4, 8, 12, 16, 20 g m−2 N fertilizer). A rice growth model that was developed and already validated for 9 different genotypes grown under 7 sites in Asia was used for the simulation, integrating additional components into the model to explain the direct effect of [CO2] on several physiological processes. The model predicted that the relative yield response to elevated [CO2] (RY, the ratio of yield under 700 ppm [CO2] to that under 360 ppm [CO2]) increased with increasing N fertilizer, ranging from 1.12 at 4 g m−2 N fertilizer to 1.22 at 20 g m−2 N fertilizer, averaged overall genotypes and locations. The model also predicted a large genotypic variation in RY at the 20 g N treatment, ranging from 1.08 for ‘WAB450-I-B-P-38-HB’ to 1.41 for ‘Takanari’ averaged overall locations. Combining all genotypes grown at the 5N fertilization conditions, a close 1:1 relationship was predicted between RY and the relative [CO2] response in spikelet number for crops with a small number of spikelets (less than 30,000 m−2) under the current atmospheric [CO2] (n = 18, r = 0.89***). In contrast, crops with a large number of spikelets under the current atmospheric [CO2] showed a significantly larger RY than the relative [CO2] response for spikelet number per unit area. The model predicted that crops with a larger number of spikelets under the current atmospheric [CO2] derived great benefit from elevated [CO2] by directly allocating increased carbohydrate to their large, vacant sink, whereas crops with a smaller number of spikelets primarily required an increased spikelet number to use the increased carbohydrate to fill grains. The simulation analyses suggested that rice with a larger sink capacity relative to source availability under the current atmospheric [CO2] showed a larger yield response to elevated [CO2], irrespective of whether genotype or N availability was the major factor for the large sink capacity under the current [CO2]. The model predicted that the RY response to nitrogen was brought about through the N effects on spikelet number and non-structural carbohydrate accumulation. The genotypic variation in RY was related to differences in spikelet differentiation efficiency per unit plant N content. Further model validation about the effects of [CO2] on growth processes is required to confirm these findings considering data from experimental studies. 相似文献
89.
Hiroe Yoshida Kunihiko Takehisa Toshihiko Kojima Hiroyuki Ohno Kaori Sasaki 《Plant Production Science》2016,19(1):30-42
The objective of this study was to propose a model for explaining rice responses to a wide range of N application rates in various growth attributes associated with the occurrence of chalky grains. We improved the sub-model for N uptake process of a previous rice model which was originally developed for explaining genotypic and environmental variations in the whole growth processes, considering the difference in the rate of N loss from the plant-soil system between indigenously supplied soil mineral N and fertilizer N. A total of 80 growth datasets of cultivar ‘Koshihikari’ grown at Shiga prefecture, Japan, in 2010 was utilized for the calibration and validation of the model. The rice growth model well explained the above-ground biomass growth (RMSD = 78.7 g m?2) and rough dry grain yield (RMSD = 83.2 g m?2) for the validation data-set, simultaneously. The simulated carbohydrate content available per single spikelet was negatively correlated with the observed percentage of the milky-white grain which includes white-cored grain (r = ?.77, p < .001) for all the data-sets of calibration and validation. On the other hand, the observed percentage of the sum of white-back and white-base grains was closely correlated with the simulated plant N content available per single spikelet (r = ?.59, p < .001). It was suggested that the present rice growth model would rationally explain the effects of N application on the occurrence of the chalky grains through the dynamic change of the carbohydrate content and plant N content available per single spikelet. 相似文献
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