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904.
Tetsuya Nishikawa Yukinobu Nakamura Shigeyoshi Okamoto Hiroshi Ueda 《Fisheries Oceanography》2020,29(1):52-55
Annual catch of the western sand lance Ammodytes japonicus in the eastern Seto Inland Sea, Japan, has shown a decreasing trend since the 1990s. To examine whether food shortage was the main cause for the catch decrease, we investigated the condition factor of the age‐0 fish at the beginning of the estivation period (late July) in Harima‐Nada, eastern Seto Inland Sea, for 10 years from 2008 to 2017. The mean abundance of copepods as food for the age‐0 fish during the fish growth period (from February to June) around the estivation area was also determined. The condition factor showed a significant decrease, and values for 2011 and later years were mostly lower than the known minimum threshold (4.2) for maturation. In the recent 4 years from 2013 to 2016, the mean copepod abundance was much lower than values for the other years. The condition factor showed a significant positive correlation with the copepod abundance. These results indicate that decline of western sand lance catch after 1990 was caused mainly by food shortage. 相似文献
905.
Okamoto Mineo Yap Minlee Roeroe Andreus Kakaskasen Nojima Satoshi Oyamada Kumi Fujiwara Shuichi Iwata Itaru 《Fisheries Science》2010,76(2):343-353
The growth of Acropora in Sekisei Lagoon was investigated in situ using ceramic coral settlement devices (CSDs) and marine blocks (MBs) with small
holes on their surfaces that were deployed prior to a mass spawning event. Acropora that had settled in 10-mm holes on the upper surface of the MBs were found to have grown inwards after 348 days post-mass
spawning. After 733 days, the colonies had grown outwards, encrusting the blocks and attaining a maximum diameter of 21.5 mm
(3.7 mm). CSDs that had been stacked above each other on frames were separated and observed in situ on 405 and 764 days after
mass spawning. After 405 days, the maximum diameter of the encrusting Acropora was 7.6 mm (±2.4 mm), which increased to 19.4 mm (±5.5 mm) after 764 days, with 30% of colonies extending short branches.
The length of the branches of Acropora grown on the CSDs fixed to the MBs 3 months after the mass spawning event exceeded the size of the encrusting portion of
the colony 629 days after spawning. The mortality of colonies between 1 and 2 years was slight, with the temperatures conducive
to coral bleaching that occurred during the study also having only a slight effect. 相似文献
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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
908.
Anthony D. M. Glass Dev T. Brito Brent N. Kaiser Herbert J. Kronzucker Anshuman Kumar Mamaru Okamoto S. R. Rawat Mohammed Y. Siddiqi Salim M. Silim Joseph J. Vidmar Degen Zhuo 《植物养料与土壤学杂志》2001,164(2):199-207
Physiological methods, especially the use of isotopes of N, have allowed for the detailed characterizations of the several putative transport systems for nitrate and ammonium in roots of higher plants. In the last decade, the cloning of genes that appear to encode both high- and low-affinity transporters represent major advances, as well as substantiating the inferences based on earlier physiological methods. Nevertheless, the unexpected plethora of genes that have been identified now presents even greater challenges, to resolve their individual functions and to attempt to place these functions in a whole plant/environmental context. 相似文献
909.
Kan He Lu Zeng Qing Ye Guoen Shi Nicholas H. Oberlies Geng-Xian Zhao C. Jesse Njoku Jerry L. McLaughlin 《Pest management science》1997,49(4):372-378
The activities of 44 Annonaceous acetogenins, which were originally isolated by monitoring plant fractionations with the brine shrimp lethality test (BST), were evaluated in the yellow fever mosquito larvae microtiter plate (YFM) assay. The results clearly demonstrate that most acetogenins have pesticidal properties. The structure–activity relationships indicate that the compounds bearing adjacent bis-THF (tetrahydrofuran) rings with three hydroxyl groups are the most potent. Bullatacin ( 1 ) and trilobin ( 7 ) gave the best activities against YFM with LC50 values of 0·10 and 0·67 mg litre-1, respectively. Compounds showing LC50 values below 1·0 mg litre-1 in this assay are usually considered significant as new lead candidates for pesticidal development. In the BST, the corresponding LC50 values were 1·6×10-3 ( 1 ) and 9·7×10-3 ( 7 ) mg litre-1. This is the first report of pesticidal structure–activity relationships for a series of Annonaceous acetogenins which are known to act, at least in part, as potent inhibitors of mitochondrial NADH: ubiquinone oxidoreductase. © of SCI. 相似文献
910.