Oxidative Dissolution of Sulfide Minerals Tends to Accumulate More Dissolved Heavy Metals in Deep Seawater Environments than in Shallow Seawater Environments.

Deep-sea mining magnifies the release of heavy metals into seawater through oxidative dissolution of seafloor massive sulfide (SMS). At present, there is little information about how the metals released into seawater might be affected by the mineral assemblages, seawater conditions, and solid percentages. Here, leaching experiments were carried out to examine the behavior of three sulfides from the Southwest Indian Ridge, under conditions that replicated deep and shallow seawater environments at three solid-liquid ratios.

Transformation of minerals and mobility of heavy metals during oxidative weathering of seafloor massive sulfide and their environmental significance.

Seafloor massive sulfide (SMS) deposits have received widespread attention because of their potential as available metal resources. Deep-sea mining operations significantly increase the exposure of fresh sulfide to oxygenated seawater. Knowledge about mineral transformation and the fate of heavy metals during sulfide oxidation remains insufficient, which is unfavorable for eco-friendly deep-sea mining.

The prevalence and risk factors of potentially inappropriate medication use in older Chinese inpatients with multimorbidity and polypharmacy: a cross-sectional study.

Background: Multimorbidity and polypharmacy are common problems among the older population globally. They not only reduce the quality of life of older adults but also increase the prevalence of potentially inappropriate medication (PIM) use. This study aimed to examine the prevalence and the predictors of PIMs in hospitalized geriatric patients with multimorbidity and polypharmacy in Chengdu based on the 2015 American Geriatric Society Beers Criteria (2015 AGS Beers Criteria) and 2019 American Geriatric Society Beers Criteria (2019 AGS Beers Criteria).

Deep high-temperature hydrothermal circulation in a detachment faulting system on the ultra-slow spreading ridge.

Coupled magmatic and tectonic activity plays an important role in high-temperature hydrothermal circulation at mid-ocean ridges. The circulation patterns for such systems have been elucidated by microearthquakes and geochemical data over a broad spectrum of spreading rates, but such data have not been generally available for ultra-slow spreading ridges. Here we report new geophysical and fluid geochemical data for high-temperature active hydrothermal venting at Dragon Horn area (49.

Melting of recycled ancient crust responsible for the Gutenberg discontinuity.

A discontinuity in the seismic velocity associated with the lithosphere-asthenosphere interface, known as the Gutenberg discontinuity, is enigmatic in its origin. While partial mantle melts are frequently suggested to explain this discontinuity, it is not well known which factors critically regulate the melt production. Here, we report geochemical evidence showing that the melt fractions in the lithosphere-asthenosphere boundary were enhanced not only by accumulation of compacted carbonated melts related to recycled ancient marine sediments, but also by partial melting of a pyroxene-rich mantle domain related to the recycled oceanic eclogite/pyroxenites.

Synthesis, Characterization, and Biological Evaluations of 1,3,5-Triazine Derivatives of Metformin Cyclization with Berberine and Magnolol in the Presence of Sodium Methylate.

The novel target products were synthesized in the formation of a triazine ring from berberine, magnolol, and metformin catalyzed by sodium methylate. The structures of products - were firstly confirmed by extensive spectroscopic analyses and single-crystal X-ray diffraction. The crystal structures of the target product and the intermediate product were reported for the first time.