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This paper presents a new method for the recovery of iron and rare earth elements (REEs) from Bayan Obo tailings, which are the waste materials from the extraction of iron and REEs from the Bayan Obo ore deposit in Inner Mongolia, China. The method is based on the combination of microwave-assisted carbothermal reduction and acid leaching. The microwave-assisted carbothermal reduction can effectively reduce the iron oxides and REE oxides in the tailings to metallic iron and REE metals, respectively, and separate them from the gangue minerals. The acid leaching can then dissolve the REE metals from the reduced product and obtain a high-purity REE solution. The effects of various parameters on the performance of the method were investigated and optimized, and the mechanisms and kinetics of the reactions were analyzed and modeled. The results showed that the method can achieve a high recovery rate of iron and REEs, a high selectivity of REEs, a low energy consumption, and a simple process. The economic and environmental benefits of the method are also significant, as it can utilize the Bayan Obo tailings and recover the valuable elements from them, and reduce the waste generation and greenhouse gas emission. The method provides a new and efficient technology for the utilization of Bayan Obo tailings and the recovery of iron and REEs, and contributes to the fundamental understanding of the microwave-assisted carbothermal reduction and acid leaching processes.

Scandium can used in unique electronic or alloying materials such as aluminum-scandium alloys, magnesia-scandium alloys, laser glasses, superconductors and electronic components. However, there is no single scandium mine in the world. Scandium is usually associated with other minerals and is found in very low amounts. Therefore, it is very difficult to obtain scandium and it is of great significance to explore the appropriate extraction process for the production of scandium. This paper highlights key applications of scandium, resource characterization, and production advances with less polluting. It provides environmentally friendly methods for improve scandium product recovery, and optimize the existing process.

Aim: To investigate the current situation and need for post-competence training for psychiatric nurses in China and provide a reference for the development of training programs for psychiatric nurses., Design: A cross-sectional design., Methods: A cross-sectional study was conducted from August to October 2023 with 435 psychiatric nurses from 34 hospitals in 24 provinces of mainland China. A self-administered questionnaire was used for data collection. Descriptive statistics, non-parametric tests, and chi-square tests were used for data analysis., Results: The training content for psychiatric nurses is extensive, and the training load is large. Psychiatric nurses have high training demands for first aid knowledge, emergency handling ability, and anti-riot skills. Nurses with different years of experience have different training needs. The training needs of psychiatric nurses in specialized and general hospitals also different., Conclusion: The training status of psychiatric nurses is not consistent with the demand. Managers should combine this with psychiatric nurses' own work needs to develop practical and effective training programs., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Tan, Pan, Wan, Yang, Zhang, Fang, Li and Shen.)

Importance: It is uncertain whether intravenous methylprednisolone improves outcomes for patients with acute ischemic stroke due to large-vessel occlusion (LVO) undergoing endovascular thrombectomy., Objective: To assess the efficacy and adverse events of adjunctive intravenous low-dose methylprednisolone to endovascular thrombectomy for acute ischemic stroke secondary to LVO., Design, Setting, and Participants: This investigator-initiated, randomized, double-blind, placebo-controlled trial was implemented at 82 hospitals in China, enrolling 1680 patients with stroke and proximal intracranial LVO presenting within 24 hours of time last known to be well. Recruitment took place between February 9, 2022, and June 30, 2023, with a final follow-up on September 30, 2023., Interventions: Eligible patients were randomly assigned to intravenous methylprednisolone (n = 839) at 2 mg/kg/d or placebo (n = 841) for 3 days adjunctive to endovascular thrombectomy., Main Outcomes and Measures: The primary efficacy outcome was disability level at 90 days as measured by the overall distribution of the modified Rankin Scale scores (range, 0 [no symptoms] to 6 [death]). The primary safety outcomes included mortality at 90 days and the incidence of symptomatic intracranial hemorrhage within 48 hours., Results: Among 1680 patients randomized (median age, 69 years; 727 female [43.3%]), 1673 (99.6%) completed the trial. The median 90-day modified Rankin Scale score was 3 (IQR, 1-5) in the methylprednisolone group vs 3 (IQR, 1-6) in the placebo group (adjusted generalized odds ratio for a lower level of disability, 1.10 [95% CI, 0.96-1.25]; P = .17). In the methylprednisolone group, there was a lower mortality rate (23.2% vs 28.5%; adjusted risk ratio, 0.84 [95% CI, 0.71-0.98]; P = .03) and a lower rate of symptomatic intracranial hemorrhage (8.6% vs 11.7%; adjusted risk ratio, 0.74 [95% CI, 0.55-0.99]; P = .04) compared with placebo., Conclusions and Relevance: Among patients with acute ischemic stroke due to LVO undergoing endovascular thrombectomy, adjunctive methylprednisolone added to endovascular thrombectomy did not significantly improve the degree of overall disability., Trial Registration: ChiCTR.org.cn Identifier: ChiCTR2100051729.

Objectives: The liver X receptors (LXRs) are members of the nuclear hormone receptor superfamily, and LXR-β is an important receptor for cholesterol content in brain cells. LXR-β/retinoic X receptor (RXR-α)/ATP binding cassette transporter A1 (ABCA1) cholesterol transmembrane transport system is closely related to the occurrence and development of Alzheimer's disease (AD). LXR agonist TO901317 can affect the accumulation of β- amyloid protein in the brain tissue of APP/PS1 double transgenic AD mice. However, the molecular mechanism is not clarified in detail. This study aims to evaluate the effects of LXR agonist TO901317 on the cognitive function of AD mice fed with high cholesterol diet, and to explore its possible mechanism from the perspective of cholesterol metabolism., Methods: Twenty four male 6-month-old APP/PS1 double transgenic AD mice were randomly divided into 4 groups, 6 mice in each group: a control group (fed with normal diet), a cholesterol rich diet (CRD) group, a TO901317 group (fed with CRD combined with TO901317), and a GSK2033 group (fed with CRD combined with TO901317 and LXR antagonist GSK2033). The mice were fed with pellet feed made of high cholesterol feed, mixed with lard, egg yolk powder, and cod liver oil twice a day. TO901317 and GSK2033 were dissolved and diluted to a final concentration at 0.03%. The drugs were given to the mice daily through gastric tube according to their body weight. Meanwhile, the mice in the drug group were fed with high cholesterol diet . After feeding for 3 months, Morris water maze was used to observe the changes of spatial exploration and memory ability of AD mice in each group. The contents of TC, LDL, and HDL in serum of mice in each group were detected by cholesterol enzyme colorimetry, and the differences among the groups were compared. The expression of Aβ 42 in the brain of AD mice was detected by ELISA. Western blotting was used to detect the protein levels of LXR-β, RXR-α, ABCA1, and Caveolin-1 in the brain of each group., Results: Morris water maze results showed that the times, distance and the duration of mice crossing the platform in the CRD group were significantly decreased compared with the control group (all P <0.05), while these three figures in TO901317 group were significantly increased compared with the CRD group (all P <0.05). Compared with the TO901317 group, there was a decrease of these figures in the GSK2033 group (all P <0.05). The serum TC and LDL levels in the CRD group were significantly higher than those in the control group, while HDL levels were significantly lower (all P <0.001). The figures of the TC and LDL contents level in the TO901317 group were lower than those in the CRD group, while HDL levels were higher (all P <0.001). Compared with TO901317 group, the contents of the TC and LDL in GSK2033 group were significantly increased, while HDL content was significantly decreased (all P <0.001). ELISA results showed that the production of Aβ 42 peptides in the brain of CRD group was the highest while the content in the TO901317 group was significantly decreased ( P <0.001), which was the lowest among the groups. The figure in the control group was close to the GSK2033 group. Western blotting results showed that the protein levels of LXR-β, RXR-α, and ABCA1 in the CRD group were significantly decreased compared with the control group, but the protein level of Caveolin-1 was increased (all P <0.01). After TO901317 treatment, the protein levels of LXR-β, RXR-α and ABCA1 were significantly increased, while the protein level of Caveolin-1 was decreased partially (all P <0.001). In the GSK2033 group, the effect of TO901317 on AD mice was partially reversed by GSK2033. Compared to TO901317 group, the protein levels of LXR-β, RXR-α, and ABCA1 showed a decrease trend, while the protein level of Caveolin-1 showed an increase state (all P <0.05)., Conclusions: High cholesterol diet leads to severer spatial exploration, learning and memory impairment in transgenic AD mice, while the LXR agonist TO901317 attenuates this effect. The mechanism may be that TO901317 promotes cholesterol efflux by activating LXR-β/RXR-α/ABCA1 transmembrane transport system, reduces the expression of Caveolin-1, improves the composition of lipid raft, and ultimately reduces the production of Aβ 42 in the brain.

Constructing van der Waals (vdW) heterostructures has been proved to be an excellent strategy to design or modulate the physical and chemical properties of 2D materials. Here, we investigated the electronic structures and solar cell performances of the g-C 3 N 4 /WTe 2 heterostructure via first-principles calculations. It is highlighted that the g-C 3 N 4 /WTe 2 heterostructure presents a type-II band edge alignment with a band gap of 1.24 eV and a corresponding visible light absorption coefficient of ∼10 6 cm -1 scale. Interestingly, the band gap of the g-C 3 N 4 /WTe 2 heterostructure could increase to 1.44 eV by enlarging the vdW gap to harvest more visible light energy. It is worth noting that the decreased band alignment difference resulting from tuning the vdW gap, leads to a promotion of the power conversion efficiency up to 17.68%. This work may provide theoretical insights into g-C 3 N 4 /WTe 2 heterostructure-based next-generation solar cells, as well as a guide for tuning properties of vdW heterostructures., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)