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The Wutonggou iron deposit is located in the well-known iron metallogenic belt in the eastern Tianshan, NW China, and has been regarded as a sedimentary iron deposit. Although hydrothermal overprinting could play indispensable roles in the formation of high-grade iron ores in sedimentary iron deposits, previous studies mainly focused on sedimentary-related iron mineralization, while the nature and contribution of hydrothermal fluids are poorly constrained. Accordingly, an integrated study of ore geology, H-O-C isotopes and 40Ar-39Ar dating, is conducted on the Wutonggou deposit, in order to reveal the features, source, and timing of hydrothermal mineralization. The studied deposit includes two mining sections namely the Jianshan and Wutonggou. The δ18O values of early magnetite from the Jianshan section range from +3.0‰ to +5.8‰ that nearly consistent with classic magmatic magnetite, while increase to 6.3‰–8.0‰ in the late stage. Quartz from the two sections shows comparable H-O isotopic compositions and identical fractionation trends, and is plotted in or periphery to the primary magmatic water area. Calcites from the two sections are broadly similar in carbon and oxygen isotopic compositions, and siderite from the Wutonggou section is plotted in the same region. Thus, comparable stable isotopic compositions and evolution trends indicate similar magmatic fluids contributed hydrothermal iron mineralization in the two mining sections. Moreover, water-rock interactions of varying degrees generated distinct mineralization styles in the Jianshan and Wutonggou sections, and caused the isotopic fractionation in late stages. Biotite extracted from a hydrothermal siderite ore yielded a 40Ar-39Ar plateau age of 299.5 ± 2.0 Ma, indicates the timing of hydrothermal iron mineralization is corresponding to the emplacement of vicinity granitoids. Taken together, the hydrothermal mineralization in the Wutonggou iron deposit was the product of remobilization and upgrading of early sedimentary iron ores, and ore-forming fluids were most probably originated from regional granitic magmatism. [ABSTRACT FROM AUTHOR]

Acute ischemic stroke is one of the common diseases in Chinese, among which acute ischemic stroke with large vessel occlusion(AIS-LVO))has the most serious complications and has the risk of death. Studies have shown that reperfusion is a first-line treatment for the effective rescue of ischemic brain tissue, usually mainly by mechanical thrombectomy (MT), supplemented by intravenous thrombolysis. However, there are still complications after large blood vessel occlusion and MT. such as bleeding and infection at the puncture point, vasospasm, vascular dissection, subarachnoid hemorrhage, hemorrhagic transfomation, reembolization, and massive cerebral infarction, etc. The high risk factors and corresponding measures of complications after MT by reviewing the research analysis. [ABSTRACT FROM AUTHOR]

A core‐shell structured Pd@TS‐1@meso‐SiO2 catalyst with confined Pd nanometals has been fabricated by one‐pot synthesis, impregnation method and sol‐gel method. With the promotion of acid sites and protection of mesoporous silica shell, Pd@TS‐1@meso‐SiO2 shows higher activity than commercial comparison and higher stability than sample without mesoporous silica shell in the hydrogenation of nitrobenzene. The schematic illustration of the synergy effect is also proposed. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a chronic progressive neurodegenerative disease. Deep brain stimulation (DBS) is an effective treatment for patients with advanced PD. There are many DBS targets for PD, including subthalamic nucleus (STN), globus pallidus (GPi), meso-ventral thalamic nucleus (VIM), pontine peduncle nucleus (PPN), posterior subthalamic region (PSA) and zonation of undetermined zone (ZI). This paper summarizes the efficacy of each target in the treatment of PD with DBS, not only makes a systematic analysis and comparison of motor symptoms, but also makes a detailed description of the efficacy of non-motor symptoms, so as to provide a personalized treatment basis for PD patients to select appropriate target targets in DBS. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have great potential for producing photoelectrocatalyzed hydrogen and degrading pollutants, owing to several factors such as high porosity and tunable semiconductor-like properties. Wide band gaps, which restrict their use to only UV light induced reactions, and low efficiencies for the separation of photogenerated charge carriers (electrons and holes) pose significant challenges to the widespread applications of MOFs. In this study, a hierarchical hollow Pt@H-UiO-66-NH2/CdS ternary catalyst was designed and synthesized. The immobilized CdS nanoparticles (NPs) in this catalyst endow the MOF H-UiO-66-NH2 with high visible light absorption ability and the Pt NPs serve as electron sinks to improve charge carrier separation. Furthermore, the hierarchical hollow structure of H-UiO-66-NH2 in the composite contributes to boosting light absorption and shortening the distance for charge transfer. As a proof of principle, Pt@H-UiO-66-NH2/CdS catalyzes methylene blue (MB) degradation with a high rate constant of 1.025 × 10−2 and hydrogen production with a rate of 12 810 μmol g−1 h−1, the latter of which is about 2.3, 11.7 and 173 times higher than those of Pt@UiO-66-NH2/CdS, H-UiO-66-NH2/CdS and Pt@H-UiO-66-NH2, respectively. [ABSTRACT FROM AUTHOR]

Hierarchical TiO2 nanofibers with enriched surface hydroxyl groups and oxygen vacancies have been synthesized. An assessment of their photocatalytic properties shows that the new catalyst has high stability and exhibits excellent photocatalytic H2 production performance in seawater. The enhanced activity of the catalyst is a consequence of the elevation in the rates of charge transfer and H+ adsorption by the synergistic effects of surface hydroxyls and oxygen vacancies. [ABSTRACT FROM AUTHOR]

Uncovering an efficient and stable photocatalytic system for seawater splitting is a highly desirable but challenging goal. Herein, Cd0.2Zn0.8S@Silicalite-1 (CZS@S-1) composites, in which CZS is embedded in the hierarchical zeolite S-1, were prepared and show remarkably high activity, stability and salt resistance in seawater. [ABSTRACT FROM AUTHOR]

The Xiaoqinling Precambrian metamorphic terrane is located in the southern margin of the North China Craton, where it is the second largest gold‐producing province in China. The Huashan, Wenyu, and Niangniangshan granitic plutons are distributed from west to east across the Xiaoqinling terrane. To fully reveal the terrane's cooling and uplift history, a systematic thermochronological study of the Niangniangshan pluton was carried out in this work. Combined with previous data for the other two plutons, our new data allow us to draw four important conclusions: (a) The Niangniangshan granitic pluton has experienced three cooling–uplift stages, with a rapid stage from 141.7 to 118.5 Ma, a second slow stage from 118.5 to 40.3 Ma, and a final relatively rapid stage from 40.3 to 29.0 Ma. Correspondingly, the cooling rates are 17.24°C/Ma, 0.77°C/Ma, and 11.50°C/Ma. (b) The three plutons experienced similar post‐emplacement rapid cooling stages until ca. 120 Ma, with high cooling rates of about 17–20°C/Ma. Subsequently, their host terrane entered a long period of tectonic quiescence with cooling rates of less than 1°C/Ma. A new diachronous rapid cooling stage began first in the west at 57 Ma, then in the centre at 45 Ma, and finally in the east at 40 Ma with markedly different cooling rates. In this latter rapid stage, the Huashan and Wenyu plutons experienced a much more rapid cooling and uplift than the Niangniangshan pluton, resulting in the higher elevations and larger outcrop area of granitoids in the west and centre of the terrane than in the east. Consequently, the present topography of the Xiaoqinling terrane was close to present‐day form by the Eocene–Oligocene. (c) The emplacement of the three plutons was prior to the regional extension and detachment faulting in the Xiaoqinling terrane, with the evolution of magmatic thermal domes triggering development of the Xiaoqinling metamorphic core complex. (d) Gold mineralization of the Xiaoqinling goldfield took place at ca. 132–125 Ma, which was coeval with the early rapid cooling stage of the plutons and the extensional detachment faulting of the Xiaoqinling metamorphic core complex. Regionally, the gold mineralization overlaps lithospheric thinning and asthenospheric upwelling below the entire eastern part of the North China Craton that occurred during the major extensional regime in the late Early Cretaceous. [ABSTRACT FROM AUTHOR]

Hosted by volcaniclastics of the Carboniferous Dahalajunshan Formation, the Songhu iron deposit is located in the central segment of the Awulale metallogenic belt, Chinese Western Tianshan. Mineralization and alteration are structurally controlled by orogen-parallel NWW-striking faults. Integrating with mineralogical and stable isotopic analyses based on paragenetic relationships, two types of iron mineralization have been identified. The deuteric mineralization (Type I) represented by brecciated, banded, and disseminated-vein ores juxtaposed with potassic-calcic alteration in the inner zone, which was formed from a magmatic fluid generated during the late stages of regional volcanism. In contrast, the volcanic-hydrothermal mineralization (Type II) is characterized by hydrothermal features occurring in massive and agglomerated ores with abundant sulfides, and was generated from the magmatic fluid with seawater contamination. Two volcaniclastic samples from the hanging and footwall of the main orebody yield zircon U-Pb ages of 327.8 ± 3.1 and 332.0 ± 2.0 Ma, respectively, which indicate Middle Carboniferous volcanism. Timing for iron mineralization can be broadly placed in the same epoch. By reviewing geological, mineralogical, and geochemical features of the primary iron deposits in the Awulale metallogenic belt, we propose that the two types of iron mineralization in the Songhu iron deposit are representative regionally. A summary of available geochronological data reveals Middle-Late Carboniferous polycyclic ore-related volcanism, and nearly contemporaneous iron mineralization along the belt. Furthermore, petro-geochemistry of volcanic-volcaniclastic host rocks indicates that partial melting of a metasomatized mantle wedge under a continental arc setting could have triggered the continuous volcanic activities and associated metallogenesis. [ABSTRACT FROM AUTHOR]