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71.
72.
Sato Minoru Oba Takashi Hosokawa Takao Yamaguchi Toshiyasu Nakano Toshiki Saito Tadao Muramoto Koji Kahara T akashi Funayama Katsura Kobayashi Akio Nakano Takahisa 《中国海洋大学学报(英文版)》2005,4(3):209-213
Brown alga ( Undaria pinnatifida) was treated with alginate lyase and hydrolyzed using 17 kinds of proteases and the inhibitory activity of the hydrolysates for the angiotensin-I-converting enzyme (ACE) was measured. Four hydrolysates with potent ACE-inhibitory activity were administered singly and orally to spontaneously hypertensive rats (SHRs). The systolic blood pressure of SHRs decreases significantly after single oral administration of the brown alga hydrolysates by pro- tease S ' Amano' (from Bacillus stearothermophilus) at the concentration of 10 (mg protein) (kg body weight)^ - 1. In the 17 weeks of feeding experiment, 7-week-old SHRs were fed standard diet supplemented with the brown alga hydrolysates for 10 weeks. In SHRs fed 1.0 and 0.1% brown alga hydrolysates, elevating of systolic bloodpressure was significantly suppressed for 7 weeks. To elucidate the active components, the brown alga hydrolysates were fractionated by 1-butanol extraction and HPLC on a reverse-phase column. Seven kinds of ACE-inhibitory peptides were isolated and identified by amino acid composition analysis, sequence analysis, and LC-MS with the results Val-Tyr, Ile-Tyr, Ala-Trp, Phe-Tyr, Val-Trp, Ile-Trp, and Leu-Trp. Each peptide was determined to have an antihypertensive effect after a single oral administration in SHRs. The brown alga hydrolysates were also confirmed to decrease the blood pressure in humans. 相似文献
73.
Minoru Ozima 《Earth and Planetary Science Letters》1980,47(1):121-123
Compressional plastic deformation of a Cu-Co alloy in which Co particles (submicron to a few tens of microns in diameter) were precipitated in a Cu matrix resulted in a systematic rotation of remanent magnetization (IRM atH = 1000Oe) away from the axis of compression with increasing degree of the deformation. 相似文献
74.
The role of megatides and relative sea level in controlling the deglaciation of the British–Irish and Fennoscandian ice sheets 下载免费PDF全文
Key external forcing factors have been proposed to explain the collapse of ice sheets, including atmospheric and ocean temperatures, subglacial topography, relative sea level and tidal amplitudes. For past ice sheets it has not hitherto been possible to separate relative sea level and tidal amplitudes from the other controls to analyse their influence on deglaciation style and rate. Here we isolate the relative sea level and tidal amplitude controls on key ice stream sectors of the last British–Irish and Fennoscandian ice sheets using published glacial isostatic adjustment models, combined with a new and previously published palaeotidal models for the NE Atlantic since the Last Glacial Maximum (22 ka BP). Relative sea level and tidal amplitude data are combined into a sea surface elevation index for each ice stream sector demonstrating that these controls were potentially important drivers of deglaciation in the western British Irish Ice Sheet ice stream sectors. In contrast, the Norwegian Channel Ice Stream was characterized by falling relative sea level and small tidal amplitudes during most of the deglaciation. As these simulations provide a basis for observational field testing we propose a means of identifying the significance of sea level and tidal amplitudes in ice sheet collapse. 相似文献
75.
76.
Harutaka Sakai Minoru Sawada Yutaka Takigami Yuji Orihashi Tohru Danhara Hideki Iwano Yoshihiro Kuwahara Qi Dong Huawei Cai Jianguo Li 《Island Arc》2005,14(4):297-310
Abstract Newly discovered peloidal limestone from the summit of Mount Qomolangma (Mount Everest) contains skeletal fragments of trilobites, ostracods and crinoids. They are small pebble-sized debris interbedded in micritic bedded limestone of the Qomolangma Formation, and are interpreted to have been derived from a bank margin and redeposited in peri-platform environments. An exposure of the Qomolangma detachment at the base of the first step (8520 m), on the northern slope of Mount Qomolangma was also found. Non-metamorphosed, strongly fractured Ordovician limestone is separated from underlying metamorphosed Yellow Band by a sharp fault with a breccia zone. The 40 Ar–39 Ar ages of muscovite from the Yellow Band show two-phase metamorphic events of approximately 33.3 and 24.5 Ma. The older age represents the peak of a Barrovian-type Eo-Himalayan metamorphic event and the younger age records a decompressional high-temperature Neo-Himalayan metamorphic event. A muscovite whole-rock 87 Rb–86 Sr isochron of the Yellow Band yielded 40.06 ± 0.81 Ma, which suggests a Pre-Himalayan metamorphism, probably caused by tectonic stacking of the Tibetan Tethys sediments in the leading margin of the Indian subcontinent. Zircon and apatite grains, separated from the Yellow Band, gave pooled fission-track ages of 14.4 ± 0.9 and 14.4 ± 1.4 Ma, respectively. These new chronologic data indicate rapid cooling of the hanging wall of the Qomolangma detachment from approximately 350°C to 130°C during a short period (15.5–14.4 Ma). 相似文献
77.
Volcanism in the Sumisu Rift, I. Major element, volatile, and stable isotope geochemistry 总被引:2,自引:0,他引:2
Alfred G. Hochstaedter James B. Gill Minoru Kusakabe Sally Newman Malcolm Pringle Brian Taylor Patty Fryer 《Earth and Planetary Science Letters》1990,100(1-3)
A bimodal volcanic suite with KAr ages of 0.05–1.40 Ma was collected from the Sumisu Rift using alvin. These rocks are contemporaneous with island arc tholeiite lavas of the Izu-Ogasawara arc 20 km to the east, and provide a present day example of volcanism associated with arc rifting and back-arc basin initiation. Major element geochemistry of the basalts is most similar to that of basalts found in other, more mature back-arc basins, which indicates that back-arc basins need not begin their magmatic evolution with lavas bearing strong arc signatures.Volatile concentrations distinguish Sumisu Rift basalts from island arc basalts and MORB. H2O contents, which are at least four times greater than in MORB, suppress plagioclase crystallization. This suppression results in a more mafic fractionating assemblage, which prevents Al2O3 depletion and delays the initiation of Fe2O3(tot) and TiO2 enrichment. However, unlike arc basalts,Fe3+/ΣFe ratios are only slightly higher than in MORB and are insufficient to cause magnetite saturation early enough to suppress Fe2O3(tot) and TiO2 enrichment. Thus, major element trends are more similar to those of MORB than arcs.H2O, CO2 and S are undersaturated relative to pure phase solubility curves, indicating exsolution of an H2O-rich mixed gas phase. HighH2O/S, highδD, and low (MORB-like)δ34S ratios are considered primary and distinctive of the back-arc basin setting. 相似文献
78.
Edward D. Goldberg Vern Hodge Minoru Koide John Griffin Eric Gamble Owen P. Bricker Gerry Matisoff George R. Holdren Ruth Braun 《Geochimica et cosmochimica acta》1978,42(9):1413-1425
Present day anthropogenic fluxes of some heavy metals to central Chesapeake Bay appear to be intermediate to those of the southern California coastal region and those of Narragansett Bay. The natural fluxes, however, are in general higher. On the bases of Pb-210 and Pu-239 + 240 geochronologies and of the time changes in interstitial water compositions, there is a mixing of the upper 30 or so centimeters of the sediments in the mid-Chesapeake Bay area through bioturbation by burrowing mollusks and polychaetes. Coal, coke and charcoal levels reach one percent or more by dry weight in the deposits, primarily as a consequence of coal mining operations. 相似文献
79.
Stability of genetic diversity in an intertidal goby population after exposure to tsunami disturbance 下载免费PDF全文
Shotaro Hirase Minoru Ikeda Shun Hayasaka Wataru Iwasaki Akihiro Kijima 《Marine Ecology》2016,37(5):1161-1167
Massive tsunami disturbances have potentially detrimental effects on genetic diversity and effective population size of coastal marine species, and evaluating these effects can be useful for devising conservation strategies for coastal marine environments. Local populations of the intertidal goby Chaenogobius annularis, which are distributed on scattered rocky beaches of the Japanese Archipelago, show demographic independence without overlapping generations, making this an ideal species with which to study the effects of tsunami disturbance on genetic diversity. Some of these populations were affected by the tsunami of the 2011 off the Pacific coast of Tohoku Earthquake. Here, we investigated the change in genetic diversity of a local population of this species, which was located close to the epicenter of the earthquake, across the cohorts before and after the tsunami and evaluated the impact of the tsunami disturbance. Genetic diversity was maintained after the tsunami, and no change in the effective population size was observed. Our results suggest that the tsunami disturbance has had no marked impact on the genetic diversity of C. annularis. 相似文献
80.
Minoru Ozima 《Geochimica et cosmochimica acta》1975,39(8):1127-1134
Earth-atmosphere evolution models are mathematically simulated and the resulting present isotopic ratio (40Ar/36Ar) in the mantle is given for each.Differential outgassing experiments on several recent submarine glasses were made to estimate an isotopic ratio (40Ar/36Ar) in the present mantle. Estimations of (40Ar/36Ar) in the mantle by various methods are also critically reviewed. From the experimental results and these considerations a minimum value of 2000 for (40Ar/36Ar) ratio in the present mantle is inferred. By assuming that is larger than 2000 and that the potassium content in the present mantle is larger than 50 ppm, we can limit considerably a choice among various Earth-atmosphere evolution models, i.e. (1) a continuous degassing process can not explain rare gas evolution in the atmosphere, (2) early sudden degassing is more likely and (3) such sudden degassing must have occurred earlier than 4.35 b.y. 相似文献