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Changes of foot pressure pattern in post-stroke individuals who achieved independent walking during the convalescent phase
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Assessment of body composition, metabolism, and pulmonary function in patients with myotonic dystrophy type1
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GENETIC AND MOLECULAR ANALYSES OF P53 IN A JAPANESE FAMILY WITH LI-FRAUMENI SYNDROME
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Descriptive Petrology and Geochemical Study of New Basalt Volcanic Activity in Palawan Island, Northern Province, Philippines
Get PDF秋田大学博士（理学）Manguao Basalt is a basalt-basaltic andesite lava flow field found on the northeast end of Palawan Island, Philippines. The relatively stable nature of the Palawan Continental Block seemingly contradicts the presence of the geomorphologically young lava flow field. This study investigates the occurrence and origin of Manguao Basalt, and its relation to the evolution of the Palawan microcontinent.
Good exposures of the Manguao Basalt lava flow field are found nearshore. Lava flow structures and features (i.e., levees, channels, and tumuli) are still intact and observable in several locations. The lava flow is generally blocky and vesicular, with observable phenocrysts and large chert xenoliths. Macroscopic observations of obtained samples show identifiable olivine and pyroxene phenocrysts. Petrographic observations show olivine dominance in the phenocryst assemblage and plagioclase dominance in the groundmass. Pyroxenes are found both in phenocryst and groundmass assemblages. Mineral textures observed from petrography show the earlier formation of pyroxene phenocrysts from olivine. Plagioclase laths, on the other hand, show earlier crystallization from the anhedral groundmass pyroxenes. Volcanic glass fills the interstices between plagioclase and pyroxene, forming intersertal textures. A general overview of the crystallization sequence (pyroxenes → olivine → plagioclase → groundmass pyroxenes) is presented.
Major element chemistry from bulk-rock compositions characterizes the Manguao Basalt as subalkaline and tholeiitic. Bivariate diagrams show the fractionation of ferromagnesian minerals (i.e., olivine and pyroxenes) but limited fractionation in later-formed minerals (i.e., plagioclase). Total iron over magnesium (FeOt/MgO) versus silica (SiO2) plots (Miyashiro, 1974) of Manguao Basalt shows 'straddling' tholeiite and calc-alkaline character. The presence of the chert xenoliths, however, may have affected bulk silica concentrations, shifting the plots towards the calc-alkaline field. AFM ternary plots show a diagnostic early iron enrichment, reflecting a tholeiitic trend. Trace element chemistry confirms the early ferromagnesian fractionation from nickel and cobalt trends. Tectonic discrimination diagrams of Manguao Basalt show resemblance with different basalts from other known tectonic settings (i.e., continental flood basalts, island-arc basalts, continental-arc basalts, and within-plate basalts). However, the association of Manguao Basalt with ocean-island basalts (OIB) or mid-ocean ridge basalts (MORB) appeared inconclusive [i.e., plotting outside MORB-OIB array defined by Pearce (2008)]. These inconsistencies that accompany the trace element discrimination diagrams have been pointed out by Li et al. (2015). Nevertheless, their utility is in constraining the possible tectonic processes that influence melt generation and evolution. Trace element patterns in spider diagrams show the enriched melt character of Manguao Basalt. Characteristic Nb-Ta depletion is absent for Manguao Basalt, indicating source melting that is unrelated to subduction. Positive anomalies in continent-derived trace elements (e.g., Th and Pb) are observable and consistent in any spider diagram presented (Primitive Mantle-, MORB-, NMORB-, EMORB-, and OIB-normalized).
Mineral chemistry data (olivine, orthopyroxene, clinopyroxene, and plagioclase) confirm the crystallization sequence inferred from petrography. The highest Mg# was obtained from orthopyroxene phenocrysts (Mg# > 80). Calculations using orthopyroxene barometer also yielded the highest pressures (~5 kbar), while orthopyroxene thermometers (i.e., opx-liquid) yielded the highest temperatures (~1260 °C). These obtained pressure and temperature conditions were used as benchmarks for simulations of source melting and crystallization.
Melting simulations of different upper mantle sources (e.g., fertile and depleted) were done using the MELTS program. Equilibrium and fractional melting from depressurization (15 kbar → 5 kbar; T = 1350 °C and at QFM buffer) of any mantle source produce liquids that are saturated in pyroxene components. Subsequent crystallization of melt, while being at equilibrium with source and at elevated pressures (~5 kbar) produce orthopyroxenes with similar compositions to orthopyroxenes in Manguao Basalt. The formation of olivine and the rest of the groundmass cannot be reconciled with any of the simulations due to the assumption of complete crystallization at depth. The model for magmatic underplating is presented here as a possible setup for the origin of Manguao Basalt
Cytotoxic T Lymphocytes Regenerated from iPS Cells Have Therapeutic Efficacy in a Patient-Derived Xenograft Solid Tumor Model.
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Efficacy and safety of treatment with sofosbuvir plus ribavirin for hepatits C virus genotype2
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The hydrocarbon potential and sedimentary environment of the Miocene siliceous formation in Tsugaru and Akita basins, northern Japan, based on the sedimentological and geochemical analyses
Get PDF秋田大学博士（理学）The area extending from Hokkaido to the northwestern side of Honshu island in Japan is where most of the Japanese oil and gas fields occur. Several present and past studies focused on the Middle-Late Miocene siliceous sedimentary formations of Akita and Aomori Prefectures, which are considered the most prospective horizons for hydrocarbons generation. These formations occur in several locations of Akita and Aomori Prefectures and provide an excellent geological record of the Miocene paleoenvironmental evolution in the Japan Sea. However, in many areas of the Akita and Aomori Prefectures, petroleum potential and paleoenvironmental studies have not yet been performed, and minimal subsurface data are available.
This study introduces new data about the hydrocarbon potential and the paleoenvironment of the Japan Sea in the Middle-Late Miocene through the sedimentological and geochemical analysis of the Miocene sedimentary succession of Tsugaru Basin (southwestern Aomori Prefecture) and the Middle-Late Miocene Onnagawa and Iwaya Formations (central Akita Prefecture).
Rock-Eval pyrolysis analysis performed on the core and outcrop samples of the studied formations indicates that the Odoji Formation in Aomori and the Onnagawa and Iwaya Formations in Akita are characterized by a fair/good organic richness. However, these formations are immature for the generation and expulsion of hydrocarbons.
According to several wells data in the Akita Prefecture, the Onnagawa Formation and its equivalents are mature for oil in various locations of the region. The main factors that determined the maturation of potential source rocks were the burial depth and the geothermal gradient anomalies determined by the intrusion of igneous bodies in the Onnagawa Formation. On the other hand, according to the wells data in the Aomori Prefecture, the increase of burial depth did not influence the thermal maturity significantly. At the current state, mature horizons for the oil generation are still not located.
Paleoenvironmental reconstruction of depositional conditions of the Miocene formations of Akita and Aomori Prefectures was inferred from the lithofacies and geochemical composition of sediments. Major oxides revealed that the composition of Middle-Late Miocene formations is dominated by SiO2 and variable percentages of detrital oxides such as Al2O3 and K2O. The detrital oxides content is low in the lower and central parts of the Onnagawa and Odoji Formations, while it tends to increase at the top of these formations and in the Late Miocene formations (ex. Akaishi Formation). Major oxides interpretation indicates that the detrital fraction originated from a felsic source, located in a continental area. This result suggests that the detrital fraction derived from the erosion of continental rocks in the Asian continent or the land areas on the east margin of the northwestern Honshu basin. These interpretations suggest that the detrital fraction was related to the variation of the monsoon activity in the Asian continent during the Middle-Late Miocene and the variation of riverine supply from northeastern Honshu. The generally positive correlation between the TOC and the detrital oxides suggests that the dilution of organic matter by detritus contributed to the preservation of TOC.
The high concentration of the biogenic SiO2 in the formations from both Akita and Aomori regions indicates high primary productivity in the surface waters of the Japan Sea. The intense productivity delivered considerable amounts of phytoplankton organic matter in the water column. The TOC shows a slightly negative correlation with the biogenic SiO2, possibly indicating that the intense production of biogenic SiO2 generated a biogenic dilution process that impacted the TOC content.
The lithofacies and framboidal pyrite size variations indicated that paleo-oxygenation of bottom waters varied throughout the Akita and Aomori regions. The massive samples with large-size framboidal pyrite of all the formations were probably deposited in oxic/dysoxic bottom waters. On the other hand, the laminated samples with small-size framboidal pyrite of the Onnagawa Formation were deposited in anoxic bottom waters. However, no consistent difference in the TOC of massive and laminated facies, suggests that the paleo-redox conditions had a low influence in the TOC preservation in the studied formations. The only evident case of oxic degradation is represented by the Akaishi Formation in which the TOC is markedly low.
Combining the data of this and previous studies, it was possible to hypothesize the paleoenvironmental setting of Akita and Aomori regions in the Middle-Late Miocene. Both regions were characterized by a detrital input from the Asian monsoon and the riverine supply, and by the widespread activity of phytoplankton on the sea surface. An intense process of upwelling stimulated by the cold surface water and the wind energy brought nutrient elements in the sea surface, favoring the surface water bio-productivity. The different paleo-oxygenation conditions in the bottom water were determined by the mixing between north Pacific OMZ and the Japan Sea waters. The OMZ waters probably did not reach the Tsugaru Basin and the Gotanzawa areas, suggesting that the paleo-depth of these basins was shallow. On the other hand, the intermittent inflow of the OMZ waters in the Ajigasawa and Sugisawa areas determined the deposition of both massive and laminated sediments. The inflow of the OMZ was regulated by the variations of the sea-level
Practical application of non-contact alternating current electric field mixing for reagent-saving in situ hybridisation of HER2
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