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911.
912.
Wei-hua Song Zhen-lin Liang Rong Wan Fen-Fang Zhao Kinoshita Takeshi Liu-yi Huang Jia-zhi Ma Bo-hai Chen 《Fisheries Science》2012,78(3):491-501
The effect of horizontal waves on flexible netting panels placed at angles to the wave direction is studied with the aim of evaluating the testing method of pre-tensioned mooring and radial systems and flexible netting structures. The netting was hung on a frame at a specific hanging ratio for ten types of polyethylene panels. Regular waves were experimentally generated with a wave period varying from 0.8 to 2.0 s and wave height ranging from 50 to 250 mm. The force on the netting structure was recorded by a tension transducer and a digital signal recorder. The results showed that the horizontal wave force on the netting panel changed periodically and asymmetrically when it was back and left or right declinate to the wave direction; similar results were found for the surface wave elevation. The opposite results were obtained when the sloping angle declinated front to the wave direction, with two obvious crests during each period. The horizontal wave force was related to the height and width of the netting panel, wave height, wave length, twine diameter, bar length of the mesh, and sloping angle relative to the wave direction. Using dual series relations, the least square approximation, and multiple stepwise regression analysis, the formula for estimating the maximum value of the wave force on the netting was obtained. 相似文献
913.
Glutathione peroxidase GPx1 was purified from the red muscle of Pacific bluefin tuna Thunnus orientalis and its enzymatic properties were characterized. The enzyme was optimally active at pH 7.4 with a specific activity for hydrogen
peroxide and a K
m of 6.7 μM. cDNA was also isolated and it contained a predicted open reading frame (ORF) encoding a 188 amino acid protein.
The phylogenetic tree shows that fish including Pacific bluefin tuna, pufferfish, and zebrafish, but not mammals, possess
two genetically distinct types of GPx1, i.e., GPx1a and GPx1b. The purified enzyme was classified as a fish GPx-1b enzyme
on the basis of the phylogenetic tree of the GPx1 family. 相似文献
914.
We measured air temperature in an urban green area that includes forest and grassland and in the surrounding urban area for a full year in Nagoya, central Japan, to elucidate seasonal variations of the difference in air temperature between urban and green areas. We determined the range of the “cool-island” effect as well as the relationship between vegetation cover and air temperature throughout the year. The temperature difference between urban and green areas was large in summer and small in winter. The maximum air temperature difference was 1.9 °C in July 2007, and the minimum was ?0.3 °C in March 2004. The difference was larger during the day than during the night in summer, whereas in winter the opposite relationship was true. However, winter diurnal variation was not particularly noticeable, a behaviour thought to be related to reduced shading by deciduous trees in the green area. During the night, the cooling effect of the green area reached 200–300 m into the urban area. During the day, the cooling effect between August and October 2006 exceeded 300 m and varied widely, although there was no correlation beyond 500 m. The correlation between air temperature and forest-cover ratio within a radius of 200 m from each measurement site was significant from 16:00 to 19:00. There was also a correlation during the night; this correlation was weakest in the early morning. The effect of the forest-cover ratio on air temperature was most pronounced in August 2006 and June 2007. 相似文献
915.
Yamamoto E Izawa T Juniantito V Kuwamura M Yamate J 《Journal of toxicologic pathology》2010,23(4):271-275
Cisplatin, an anticancer drug, is well known to have nephrotoxicity as an adverse effect. We investigated the expressions of cell cycle markers and prostaglandin E(2) (PGE(2)) receptors (EP) in the affected renal tubules in rats injected with a single dose (6 mg/kg body weight) of cisplatin. On days 1-3 after dosing, the affected renal epithelial cells were almost desquamated, showing necrosis. On day 5 onwards, the renal tubules were rimmed by flattened or cuboidal epithelial cells with basophilic cytoplasm; BrdU-immunopositive cells began to significantly increase, indicating regeneration. Simultaneously, TUNEL-positive apoptotic cells were also seen. On days 1-5, cyclin D1-immunopositive cells were decreased with an increased expression in p21 mRNA, indicating G(1) arrest in the cell cycle. The affected renal epithelial cells began to react to EP4 receptor, but not to EP2 receptor. Some EP4 receptor-reacting epithelial cells gave a positive reaction to BrdU or cyclin D1. Collectively, the affected renal tubules underwent various alterations such as necrosis, apoptosis, regeneration and G(1) arrest; the aspects might be influenced by endogenous PGE(2) through EP4 receptor. 相似文献
916.
To elucidate the relationships between spatiotemporal changes in leaf nitrogen (N) content and canopy dynamics, changes in leaf N and distribution in the canopy of a 26-year-old deciduous oak (Quercus serrata Thunb. ex. Murray) stand were monitored throughout the developmental sequence from leaf expansion to senescence, by estimating the leaf mass and N concentrations of all the canopy layers. Seasonal changes were observed in leaf N concentration per unit leaf dry mass (N (m)), which peaked after bud burst, declined for two weeks shortly thereafter, and then remained constant for the rest of the growing season for each canopy layer. Leaf N concentration per unit leaf area (N (a)) was higher in the upper layer than in the lower layer throughout the growing season, and was closely correlated with relative irradiance (RI) in the summer when the air temperature was moderately high. The N concentrations of all leaf layers started to decrease in November, and reached their lowest values in late November, whereas LMA scarcely changed throughout the season. The lowest N concentrations did not differ significantly among the canopy layers. Seasonal changes in the relationship between N (a) and RI were detected, indicating that N (a) is optimized temporally as well as spatially. Nitrogen resorption efficiency was highest in the upper canopy layers where larger amounts of N were invested. Based on the estimates of leaf mass and leaf N concentrations of the canopy layers, total leaf N concentration of the whole canopy was estimated to be 84.1 kg ha(-1) in the summer, and 37.3 kg ha(-1) in late November. Therefore, 46.8 kg ha(-1) of leaf N in the canopy (about 56% of the total N) was resorbed just before leaf abscission. 相似文献
917.
日本水稻增产因素分析与稻作技术评价 总被引:2,自引:0,他引:2
文章分析了日本水稻产量增长的原因,认为提早播种和机械化程度高是日本水稻产量提高的最主要因素,是通过改善作物和资源管理水平来实现的.并对日本稻作技术进行了总结. 相似文献
918.
Cyazofamid (ISO proposed common name), 4-chloro-2-cyano-N,N-dimethyl-5-p-tolylimidazole-1-sulfonamide is a novel fungicide exhibiting specific activity against diseases caused by Oomycetes. In tests, cyazofamid at 0.4-1.6 mg litre-1 exhibited excellent preventative activity against Phytophthora infestans on tomato and Pseudoperonospora cubensis on cucumber. Minimum inhibitory concentrations of cyazofamid against both diseases were over 63 times lower than those of mancozeb and at least 16 times lower than those of metalaxyl. Cyazofamid at 1.6-25 mg litre-1 exhibited not only preventative activity, but also stable residual activity and rainfastness. Cyazofamid at 6.3 mg litre-1 reduced zoosporangia formation of P infestans and P cubensis on host plants by 100 and 94% respectively. Cyazofamid also exhibited translaminar and curative activity. Cyazofamid has a new mode of action for fungicides and exhibits no cross-resistance with other currently registered and commonly used fungicides. These properties lead to a high level control by cyazofamid in field. 相似文献
919.
Derar R Haramaki S Hoque S Hashizume T Osawa T Taya K Watanabe G Miyake Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(1):19-23
To elucidate the physiological role of insulin-like growth factor-I (IGF-I) during early pregnancy in mares, number of ovarian follicles was monitored ultrasonically during different stages of the first trimester of pregnancy in 36 thoroughbred mares. From 9 of 36 mares, blood samples were collected weekly from the mating day till the end of the first trimester of pregnancy and plasma IGF-I profiles were examined with other hormones, like follicle stimulating hormone (FSH), luteinizing hormone (LH), ir-inhibin, progesterone and estradiol-17beta. Plasma IGF-I level fluctuated throughout the studied period with four peaks on the 7th, 28th, 49th and 84th days of pregnancy. Plasma IGF-I showed a positive correlation with plasma FSH (P<0.05), whereas no correlation was found with other hormones during the studied period. Plasma IGF-I had no correlation with the foetal size, but positive correlation with the number of large (> 30 mm) and medium (10-30 mm) follicles. These results suggested that IGF-I might produce from the medium and large follicles during early pregnancy and promote to develop their growth via pituitary FSH mediated effects in the mares. 相似文献
920.
Matsuda Y Sameshima T Moriura N Inoue K Nonomura T Kakutani K Nishimura H Kusakari S Takamatsu S Toyoda H 《Phytopathology》2005,95(10):1137-1143