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Sodium-glucose cotransporter 2 inhibition attenuates protein overload in renal proximal tubule via suppression of megalin O-GlcNacylation in progressive diabetic nephropathy
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Gait-related self-efficacy is directly associated with the daily number of steps in individuals with knee osteoarthritis -A cross-sectional path model analysis-
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Mineral chemistry and sulfur isotope insights into magmatic and hydrothermal processes leading to porphyry Cu mineralization at Grasberg, Indonesia
Get PDF秋田大学博士（理学）Preparation for sufficient amounts of Cl, S and metals during magma evolution is of paramount importance for the generation of porphyry Cu deposits. Reduction of oxidized S is essential for precipitation of sulfides in such deposits, in which mineralization predominantly comprises Cu sulfides, whereas their source magmas are oxidized with most of their S as SO42- and with exsolved fluids having SO2>>H2S. I explore how magma evolution and oxidation state affected the degassing of Cl- and S-bearing fluids from the source magma at Grasberg, based on igneous mineral paragenesis and amphibole, zircon and apatite chemistries. The process of S reduction required for sulfide mineralization during hydrothermal processes is also evaluated in this study on the basis of S isotope and biotite chemical composition. The low-Al amphiboles formed at approximately 730–700 °C, 1.1–0.7 kbar and FMQ+3.4 are contained in the syn-mineralization Main Grasberg Intrusion (MGI). The MGI magmatism was followed by the emplacement of the syn-mineralization Early South Kali Dike (ESKD) that contains amphibole with a disequilibrium texture of chemically distinct core and rim; the high-Al cores crystallized at approximately 900–850 °C, 4.3–3.3 kbar and FMQ+1, whereas the low-Al rims and associated low-Al amphibole phenocrysts formed at approximately 790–720 °C, 1.9–1.0 kbar and FMQ+2.7. The high-Al amphibole is anhydrite-, titanite-magnetite-quartz- and zircon-free, whereas the low-Al amphibole hosts inclusions of, and/or is associated with such minerals that indicate a high magma oxidation state. The low-Al amphiboles of both MGI and ESKD are characteristically low in REE+Y (particularly MREE) and V, and having large negative Eu, Ba, and Sr anomalies compared with the ESKD high-Al amphiboles. This confirms that the low-Al amphibole crystallized from a melt in equilibrium with plagioclase, K-feldspar, biotite, titanite (-magnetite-quartz), zircon, apatite and anhydrite, at lower pressure and temperature and higher fO2 than the conditions for the high-Al amphibole. Zircons from the MGI yield the elevated mean Ce4+/Ce3+ value of 519, whereas the ESKD zircons record a lower value of 248. Zircon Ce/Ce*, Ce/Nd and Eu/Eu* values also indicate that the MGI magma was more oxidized than the ESKD. The changes in melt Cl and S concentrations calculated from apatite chemistry indicate a degassing sequence which can be divided into: 1) degassing of Cl from the MGI magma after low-Al amphibole and plagioclase crystallizations, 2) degassing of S from the ESKD magma at ~800 °C and ~2 kbar, prior to the crystallizations of low-Al amphibole and plagioclase, 3) degassing of Cl from the ESKD magma after low-Al amphibole and plagioclase crystallizations. Initial hydrothermal events formed sulfide-free, anhydrite-rich K-feldspar and biotite alteration, followed by successive vein stages of 1) magnetite, 2) biotite, 3) quartz, 4) anhydrite-chalcopyrite, 5) chalcopyrite ± sericite selvages, and 6) pyrite-chalcopyrite- quartz + sericite selvages. Hydrothermal biotite within the potassic alteration zone is characterized by higher Mg# and lower Fe contents than igneous biotite. The ranges of δ34S values of S-bearing minerals hosted in the anhydrite- chalcopyrite veins are 1.2–4.2‰ for chalcopyrite (n=24; avg. 2.3‰), 1.1 and 2.1‰ for bornite (n=2) and 10.5–13.8‰ for anhydrite (n=26; avg. 12.2‰). Two chalcopyrite samples that occur along the centerlines of comb-textured quartz veins have δ34S values of 2.4 and 2.5‰ (n=2). One chalcopyrite vein that is accompanied by sericite alteration has δ34S = 2.1‰. The δ34S values for pyrite in a veinlet with sericite selvage are 2.8 to 4.8‰ (n=3; avg. 3.7‰), and those of anhydrite are 14.6–15.2‰ (n=2). A sample of the syn-mineralization ESKD MD yields a δ34S of 9.4‰. The combined igneous mineral paragenesis and geochemistry indicate that a less oxidized magma batch containing high-Al amphibole injected into a strongly oxidized MGI-related upper-crustal magma chamber, forming a hybrid magma from which the ESKD porphyry was derived. The degassing of Cl both from MGI and ESKD magmas is likely related to the crystallization of phenocryst in the upper crust, whereas the partitioning of S from the ESKD magma into fluids may require another process that occurs at higher pressure and temperature, prior to the crystallization of phenocrysts in the upper crustal magma chamber. I suggest that mixing of magmas of two distinct oxidation states generated SO2 by the reduction of sulfate from the oxidized magma via oxidation of Fe2+ derived from the other reduced or less oxidized magma: CaSO4 + 2FeO = CaO + SO2 + 2FeO1.5 Magmatic degassing that occurred intermittently at Grasberg implies that localized accumulation of ore-forming fluids before a sudden discharge is required for an efficient hydrothermal system. Ore-forming fluids may have been accumulated and stored in a stable fluid pocket beneath the cupola zone before a sudden discharge. Such a short-lived fluid discharge is in agreement with the fact that most porphyry deposits occur in a short period of time (>H2S). The δ34S values of sulfide-sulfate mineral pairs indicate SO2-derived SO42- and H2S in SO42-/H2S molar proportions of ~4:1 to ~3:1 at >550 °C. The hydrothermal fluid then likely followed a rock-buffered trajectory and became more reduced at <550 °C. Hydrothermal biotite that replaces igneous amphibole and biotite has a phlogopitic composition, suggesting that Fe2+ was liberated from igneous mafic minerals and oxidized by reaction with SO42- to form magnetite, resulting in sulfide formation by the simplified reaction: 12FeO + SO42- + 2H+ → 4Fe3O4 + H2
Reduction of Superoxide Dismutase 1 Delays Regeneration of Cardiotoxin Injured Skeletal Muscle in KK/Ta Ins22Akita Mice with Progressive Diabetic Nephropathy
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Prognostic value of plasminogen activator inhibitor-1 in biomarker exploration using multiplex immunoassay in patients with metastatic renal cell carcinoma treated with axitinib
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Rapid HER2 cytologic fluorescence in situ hybridization for breast cancer using noncontact alternating current electric field mixing
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Teriparatide and aerobic exercise improve bone, skeletal muscle, and fat parameters in ovariectomized and tail-suspended rats
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Evaluating critical metals for Japan and a low carbon future
Get PDF秋田大学博士（資源学）Concern about availability and access to mineral resources has increased beginning the21st Century as technological advancement increased the demand for mineral resources.Besides changing the demand landscape by altering the quantity and the composition for metals demanded,the increase in demand pushed mineral prices up, further increasing the anxiety about mineral resource availability and access. The minerals supply landscape, too, has changed. The resurgence of resource nationalism indicates a return to protectionist thinking, which has led to tension between mineral consuming and mineral producing countries. Meanwhile, the need to reduce carbon emissions to mitigate climate change could further accelerate mineral resource availability concerns. The amount of mineral resources demanded by low carbon technologies could increase rapidly and put significant pressure on the mineral demand-supply dynamics. Therefore, it is necessary to investigate the metals that have a higher chance of experiencing supply-demand tensions in the medium term and the long term, given these developments. In the medium term, Japan is one of the countries that could be heavily a ected if there is a disruption to the supply of mineral resources. Japan has created a competitive manufacturing industry that relies significantly on mineral resources despite Japan lacking a meaningful domestic supply. Despite this reliance on minerals resources by Japan's manufacturing sector, few studies not initiated by the government exist to understand Japan's critical minerals|mineral resources with high economic importance and a high risk of supply disruption. In other major economies, concerns about the availability of and access to mineral resources have prompted researchers to suggest multiple methods to identify critical materials. However,the methods proposed so far, though sensible, should be improved. This study proposes a quasi-dynamic approach that incorporates probabilities to measure the vulnerability of an economy to supply restriction of metals to improve the existing medium-term criticality methodologies. The study identifies unique probabilities for absolute price changes for 18 metals and, using economic data from Japan's economic input-output tables, identifies critical metals for Japan for 2000, 2005, 2011, and 2015. The results indicate that metal price changes follow di erent probability distributions.The study also finds that niobium, molybdenum, rare earths, vanadium, tungsten, and cobalt are critical metals for Japan, and they will remain critical for the medium term. Based on the finding for the medium-term critical metals, the study proposes several strategies for Japan to secure the supply of these critical metals, including strengthening the relationships with resource-rich countries, pushing for more recycling of valuable metals, and stockpiling. Regarding the low carbon future, the International Energy Agency(IEA) has carried out extensive modeling of future energy and transport requirements and proposed pathways to a low carbon future. However, few studies investigate the mineral resource requirements to achieve this ideal low carbon future. Based on IEA's 2 degrees scenario(2DS)(which describes an energy system consistent with emissions trajectory that climate science research indicates would limit the global temperature increase to 2°C)this study quantifies the amount of metals required by renewable energy techniologies and electric vehicles necessary to achieve the 2DS scenario. The study analyzes eight metals necessary for running five major renewable energy technologies (hydropower, geothermal, wind, solar, electric vehicles) to understand the possible additional demand for the selected metals. The study uses systems dynamic analysis with STELLA software to investigate the demand-supply progression between 2019 and 2070. By investigating additional demand and factors such as available reserves, recycling rates, available substitutes, and environmental implications, the study identifies critical metals for the long term in the context of pursuing a low carbon future. The study found that Nickel, cobalt, rear-earth elements and molybdenum will experience the most significant additional demand. However, only cobalt, lithium, and rear-earth elements are critical in the long term after considering recycling rates, substitute availability, and environmental implications. Although the study proposed improvements in measuring and displaying critical metals, it did not eliminate the need to estimate critical metals accurately. In the medium-term analysis, there is still a need to estimate the end-use application of metals accurately because the existing data on end-use and GDP are broadly aggregated, leading to overlaps in estimating metals' real economic contributions. Furthermore, important factors that could a ect the metal supply's security such as recycling rates, available metal substitutes, improvements in mining technology, and metal co-production were left out, to avoid meaningless results because of aggregating too many factors. In the long-term study, recycling rates and available substitutes were discussed but not quantitatively measured. The system dynamics model could be improved further if such factors and others like impact on the environmental and the implications, improvements in technology, and metal co-production are quantitatively measured and incorporated into the model
