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The Gacun deposit is a typical Volcanic Hosted Massive Sulfide (VHMS) associated with Late Triassic seafloor calc-alkaline felsic volcanics. Studies of zircon ages, petrology, major and trace element geochemistry, and Sr-Nd-Hf isotope geochemistry of volcanic rocks from the Northern Yidun arc were undertaken in this paper. We reshaped the Gacun magmatic system activity time, defined the origin of magma evolution, and proposed a metallogenic model of the deposit. Whole-rock major element compositions of the magmatic rocks in the Northern Yidun island arc indicate that they are a complete basalt–andesite–dacite–rhyolite assemblage, showing three obvious stages of composition evolution. They are enriched in large-ion lithophile and light rare earth elements, but depleted in high field-strength and heavy rare earth elements, with weak-to-negligible Eu anomalies (obvious in rhyolite). These geochemical features indicate that the Northern Yidun island arc is a magmatic arc based on ancient continental crust. The Ganzi–Litang oceanic subduction induced mantle melting and produced calc-alkaline basaltic magma, while the MASH processes at the bottom of the crust produced andesitic magma. Part of the andesite magma erupted to form andesite lava. The remaining part was mixed with magma produced via anatexis of ancient crust (approximately 20%–40% of the ancient crustal component), forming the ore-bearing rhyolite. Zircon U-Pb age data defines Gacun magmatic–hydrothermal mineralization sequence of events: At 238 Ma, arc magmatism led to the formation of andesite in the eastern part of the deposit. At 233 Ma, in the arc zone (the western part of Gacun deposit), a large-scale bimodal magmatism formed the main ore-bearing rock series of Gacun deposit, rhyolitic volcanic rocks. At 221 Ma, volcanic eruptions tended to end and sub-volcanic intrusion occurred, forming a lava dome, which was located under the ore-bearing rhyolitic volcanic rocks. The lava dome acted as a thermal engine and promoted hydrothermal circulation. The hydrothermal activity reached a peak at 217 ± 1 Ma, and the Gacun VHMS deposit was formed. [ABSTRACT FROM AUTHOR]

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Our aim was to clarify the incidence and risk of acute symptomatic seizures in people with coronavirus disease 2019 (COVID‐19). This multicenter retrospective study enrolled people with COVID‐19 from January 18 to February 18, 2020 at 42 government‐designated hospitals in Hubei province, the epicenter of the epidemic in China; Sichuan province; and Chongqing municipality. Data were collected from medical records by 11 neurologists using a standard case report form. A total of 304 people were enrolled, of whom 108 had a severe condition. None in this cohort had a known history of epilepsy. Neither acute symptomatic seizures nor status epilepticus was observed. Two people had seizurelike symptoms during hospitalization due to acute stress reaction and hypocalcemia, and 84 (27%) had brain insults or metabolic imbalances during the disease course known to increase the risk of seizures. There was no evidence suggesting an additional risk of acute symptomatic seizures in people with COVID‐19. Neither the virus nor potential risk factors for seizures seem to be significant risks for the occurrence of acute symptomatic seizures in COVID‐19. [ABSTRACT FROM AUTHOR]

Abstract: Surface soils from the Chengdu Economic Region (CER) were analyzed for sixteen United States Environment Protection Agency priority polycyclic aromatic hydrocarbons (PAHs) to study the spatial distribution and to identify the sources of PAHs. Relatively high concentrations (more than 1500ngg−1) of high molecular weight PAHs were found in Chengdu Plain, in the middle of CER, while high concentrations (more than 500ng g−1) of low molecular weight PAHs were detected in the surrounding mountains. The concentrations of ∑16-PAHs in topsoil samples from CER (12.52–75,431.47ngg−1, average value was 3233.92ngg−1) were higher than that from the southern China (21.91–3077ngg−1, average value was less than 500ngg−1), and they were comparable to concentrations in soils from the northern China (366–254,080ngg−1, mean value was more than 3000ngg−1). The concentrations from CER were also much higher than the concentrations of some world clean regions such as Antarctic (34.9–171ngg−1), European high mountains (9–11,000ngg−1, mean value was 158ngg−1) and some Europe residential (736ngg−1) and arable soils (60–145ngg−1, mean value was 66ngg−1). The ratio of tracer compounds (BaA/(BaA+Chr), Flo/(Flo+Pyr), and IcdP/(IcdP+BghiP)) indicated that the high concentrations of PAHs in soils were mainly derived from fossil fuels combustion in mountain region and from the incomplete combustion of petroleum in developed plain area (such as Chengdu and Deyang). From the above distribution characteristics and ratios of tracer compounds, we inferred the reasons for the distribution pattern of PAHs in CER were the domestic heating, emissions, and the physicochemical properties of PAHs. [Copyright &y& Elsevier]