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361.
Inhibiting spontaneous light emission and redistributing the energy into useful forms are desirable objectives for advances in various fields, including photonics, illuminations, displays, solar cells, and even quantum-information systems. We demonstrate both the "inhibition" and "redistribution" of spontaneous light emission by using two-dimensional (2D) photonic crystals, in which the refractive index is changed two-dimensionally. The overall spontaneous emission rate is found to be reduced by a factor of 5 as a result of the 2D photonic bandgap effect. Simultaneously, the light energy is redistributed from the 2D plane to the direction normal to the photonic crystal. 相似文献
362.
Janejira Tospornsampan Ichiro Kita Masayuki Ishii Yoshinobu Kitamura 《Paddy and Water Environment》2005,3(1):29-38
A combination of genetic algorithm and discrete differential dynamic programming approach (called GA-DDDP) is proposed and developed to optimize the operation of the multiple reservoir system. The demonstration is carried out through application to the Mae Klong system in Thailand. The objective of optimization is to obtain the optimal operating policies by minimizing the total irrigation deficits during a critical drought year. The performance of the proposed algorithm is compared with the modified genetic algorithm. The results show that the proposed GA-DDDP provides optimal solutions, converging into the same fitness values within a short time. The GA is able to produce satisfactory results that are very close to those obtained from GA-DDDP but required alot more computation time to obtain the precise results. The difficulties in selecting optimal parameters of GA as well as finding a feasible initial trial trajectory of DDDP are significant problems and time-consuming. The significant advantage obtained from GA-DDDP is saving of computational resource as GA-DDDP requires no need for optimizing parameters and deriving feasible initial trial trajectories. Because DDDP is a part of GA-DDDP, the good performance of GA-DDDP is obtained when applied to a small system where numbers of discretizations and variables have no influence to the dimensionality problem of DDDP. 相似文献
363.
The Japanese government started to construct two subsurface dams on Miyako Island in 1988, and the project was completed in 2001. Before the construction of the dams, the NO3-N concentration of groundwater on the island was about 10 mg/l, the upper limit for drinking water in Japan, owing to the application of fertilizer to sugarcane fields. Predicting the effect of these subsurface dams on the groundwater environment was difficult because they were probably the first mega-subsurface dams in the world. We measured the NO3-N concentration in the groundwater at observation wells before and after construction of the Sunagawa Dam and after the groundwater began to be used. We also measured the NO3-N concentration monthly at a typical observation well in the catchment over a period 14 years to evaluate the environmental impact of construction of the dam. The highest NO3-N concentrations were downstream before completion of the subsurface dam, and a high NO3-N concentration zone remained around the cut-off wall after its completion, but this high-concentration zone disappeared and the distribution of NO3-N became uniform after pumping of the groundwater began. Overall, the NO3-N concentration decreased gradually. These results show that the groundwater quality did not deteriorate as a result of the construction of the Sunagawa Subsurface Dam. 相似文献
364.
Sakai K Ueno Y Ueda S Yada K Fukushi S Saijo M Kurane I Mutoh K Yoshioka K Nakamura M Takehara K Morikawa S Mizutani T 《Veterinary microbiology》2009,134(3-4):227-232
An orthoreovirus was isolated from an Ostrich (Struthio camelus) and rapidly identified as orthoreovirus by the rapid determination of viral RNA sequences (RDV) system and electron microscopy. Phylogenetic analysis of the sigma A protein indicated that the isolate belonged to avian species and was closely related to chicken orthoreovirus strain 138. The results of the present study indicated that an ostrich orthoreovirus is slight different from other chicken orthoreoviruses and provided evidence of diversity among avian orthoreoviruses. To our knowledge, this is the first genetic report of an orthoreovirus isolated from an ostrich. 相似文献
365.
366.
Takeshi TSURUTA Ryo INOUE Takamitsu TSUKAHARA Noritaka MATSUBARA Masayuki HAMASAKI Kazunari USHIDA 《Animal Science Journal》2009,80(2):206-211
The immune system in juvenile calves is immature, so calves are susceptible to several diarrheal and respiratory diseases. Oral administration of lactic acid bacteria (LAB) is known to improve the growth performance and prevent diarrheal and respiratory diseases by stimulating the immune system in juvenile calves. Most of the immunostimulation by LAB is achieved by their cell wall components, and therefore we evaluated the immunostimulation of the cell preparation of Enterococcus faecalis strain EC-12 (EC-12) in juvenile calves in a clinical field. Twenty-nine 1-week old calves were used. Fourteen calves were administered 0.2% (w/w) of an EC-12 preparation that supplemented a milk replacer, and other calves were not supplemented. Feces and serum was collected at day 0, 7 and 49 after the administration to measure the IgA and IgG concentration. The fecal IgA concentration was increased by EC-12 administration at day 49, and the serum IgA concentration was also increased at day 7. These results suggested that oral administration of EC-12 in juvenile calves might have an immunostimulatory effect and provide earlier recovery of IgA levels in mucosal immunity. 相似文献
367.
Eishiro Okamoto Hitoshi Kasahara Akira Chiba Masayuki Taniguchi Eiichi Saitoh 《Fisheries Science》2009,75(2):463-471
We have discovered multiple acidic cysteine protease inhibitors, in addition to the known Eel-CPI-1, in the skin mucus extract
of the Japanese eel Anguilla japonica by using the two-dimensional gel system of gelatin reverse zymography. Two of the acidic inhibitors, which we have named
Eel-CPI-2 and Eel-CPI-3, were purified to homogeneity by anion exchange chromatography on a column of DEAE-Sepharose CL-6B,
followed by fast protein liquid chromatography on Superdex 75 10/300 GL and HiTrap Q HP columns. The amino acid compositions
of Eel-CPI-2 and Eel-CPI-3 were found to be almost identical and closely similar to that of the eel galectin AJL1. The molecular
masses of Eel-CPI-2 and Eel-CPI-3 were elucidated to be 16,089.080 and 16,089.137 Da, respectively, by matrix-assisted laser
desorption/ionization time-of-flight mass spectrometry. The apparent dissociation constant of Eel-CPI-2 and Eel-CPI-3 for
cysteine protease papain was determined to be 1.79 × 10−7 and 1.05 × 10−7 M, respectively, by a quartz crystal microbalance technique. 相似文献
368.
Hideaki Yamada Masayuki Chimura Kimio Asami Taku Sato Masato Kobayashi Atsushi Nanami 《Fisheries Science》2009,75(5):1141-1146
Microstructures of lapilli were examined for reared larvae and juveniles of black-spot tuskfish Choerodon schoenleinii. Lapilli of larvae at 1 day after hatching have one diffuse and obscure ring with an otolith radius of 4.3 ± 0.50 μm (mean ± SD,
N = 8). The slope and intercept of the regression between the number of days after hatching and increment counts did not differ
significantly from one and zero, respectively, indicating that lapillus increments were formed on a daily basis after hatching.
There was an ontogenetic shift in the relative values of somatic and otolith growth, which corresponded to the transition
from pelagic larvae to settlement stage. Simultaneously, the daily increment width reached the maximum value. These findings
suggest that age at maximum value of increment width can be used as an indicator of the planktonic larval duration while settlement
mark is not found. Since ontogenetic shift in the relationship between otolith radius and body size was observed, back-calculation
of somatic growth in black-spot tuskfish using the otolith radius during the early life stages should be analyzed with caution,
and the method requires further validation. 相似文献