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We performed a laboratory investigation at 1,873 K using a MoSi2 furnace to study the effect of refractories on inclusions in 55SiCr suspension spring steel. Three types of crucible materials (Al2O3, MgO·Al2O3, and MgO–CaO) were investigated. The results of this study indicated that SiO2, Al2O3, and MgO·Al2O3 were not suitable for making 55SiCr suspension spring steel. By contrast, MgO–CaO was a perfect choice for producing 55SiCr suspension spring steel. The advantages of using MgO–CaO crucibles to smelt 55SiCr spring steel were summarized in three aspects as follows: (i) the stability of MgO–CaO was quite good; (ii) a MgO–CaO crucible could act as a desulfurizer and dephosphorizer; (iii) finally, a MgO–CaO crucible could simultaneously remove Al2O3 inclusions.

Clarifying public willingness to pay (WTP) for farmland non‐point source pollution (FNSP) governance helps to establish an ecological compensation mechanism with public participation. This will reduce China's agricultural pollution and its environmental and food safety consequences while promoting sustainable development. Nevertheless, research has yet to reveal the public WTP within China's FNSP governance policy framework. To this end, a "2030‐oriented FNSP governance program" choice experiment with specific FNSP governance measures (fertilizer reduction, pesticide reduction, straw resource utilization, and mulch film recycling) was conducted in Gansu Province to reveal the public WTP for FNSP governance and its key influencing factors. Results from mixed logit models show that urban residents' marginal WTP (MWTP) for improving the FNSP status quo and different measures for fertilizer reduction, pesticide reduction, straw resource utilization, and mulch film recycling is ¥151.62, ¥1.33, ¥7.3, ¥4.85, and ¥3.16 annually, respectively, indicating the highest preference for reducing pesticides because of food safety problems. Meanwhile, the average individual WTP for optimal FNSP governance schemes is ¥513.02 annually, accounting for only 3.86‰ of annual household income; the regional aggregate social welfare of optimal FNSP governance is as high as ¥2038.23 million, accounting for 2.81% of GDP in 2020. This means that FNSP governance can bring substantial social welfare with a low household economic burden. In addition, the perception that food safety has improved in the past 5 years or an awareness of food safety incidents can enhance the willingness of urban residents to change the status quo of FNSP: the more serious the respondents perceive food safety problems to be, the stronger the above effects, indicating the critical impact of food safety factors on the public's WTP for FNSP governance. The study's findings highlight the potential to find socially acceptable ways to promote FNSP governance as well as provide insight into the relevant policymaking process from the standpoint of public participation and food safety. [ABSTRACT FROM AUTHOR]

Doping engineering is an effective strategy to improve the electrocatalytic activity of manganese oxides by enhancing their poor electrical conductivity and oxygen adsorption capacity. Herein, p‐block aluminum group metal ions (Al3+, Ga3+, and In3+) are introduced into cryptomelane‐type manganese oxide octahedral molecular sieves (OMS‐2), leading to p−d orbital hybridization between the p‐orbitals of the aluminum group metals and d‐orbitals of Mn, facilitating the oxygen reduction reaction. The aluminum group metal‐doped OMS‐2 exhibits excellent catalytic activity, rapid reaction kinetics, and favorable stability compared to commercial Pt/C. Among the three prepared catalysts, Ga‐doped OMS‐2 (Ga‐OMS‐2) has stronger oxygen reduction activity. Experimental and theoretical calculations show that the superiority of Ga‐OMS‐2 is attributed to p−d hybridization, which enriches the reaction sites and enhances the binding strength of the catalyst to the O2 reaction intermediates. As a proof of concept, Zinc−air batteries assembled with Ga‐OMS‐2 as a catalyst exhibit superior power density and cycle life to commercial Pt/C. This p−d hybridization strategy gives insight into the p‐block metal doping of catalysts prepared with other transition metals with excellent electrocatalytic activity and durability for energy storage and conversion. [ABSTRACT FROM AUTHOR]

Ammonia borane (AB, NH3BH3) has received much attention as a hydrogen storage material because of its high hydrogen content (19.6 wt %), low molecular weight, high solubility, high stability and non-toxicity. However, the rate of hydrogen release from AB in pure water is slow, so the development of catalysts has been a hot topic of research. A variety of high-performance catalysts have been developed to catalyze the hydrolysis of AB, but the oxidation and agglomeration of transition metals has affected their activity and stability. Metal oxides have attracted the interest of researchers as catalysts to solve this problem and various metal oxides have been developed to catalyze hydrogen production from AB hydrolysis. Therefore, a systematic analysis and summary of metal oxide-based catalysts can provide a better understanding of the development and guide for subsequent research. This review summarizes the progress of research on metal oxide-based catalysts, which is divided into two main categories: carbon-free support catalysts and carbon-based support catalysts. We emphasized on preparation methods, compositional structures, methods for performance optimization and hydrolysis mechanisms of catalysts. In addition, perspective of metal oxide catalysts are provided based on current research. [ABSTRACT FROM AUTHOR]

AbstractThis paper explores the effect of China’s Targeted Poverty Alleviation (TPA) policy by considering the child human capital of households targeted by the policy. Using data from the China Family Panel Studies, we employ a difference-in-differences strategy to identify the effect of TPA on child human capital. The evidence indicates that TPA significantly enhances beneficiary children’s health, cognitive, and non-cognitive abilities. The most substantial improvement is observed in cognitive ability, reaching 49.8 per cent of its standard deviation (0.999). Mechanism tests suggest that TPA achieves these positive outcomes primarily through improving infrastructure, alleviating resource constraints, and enhancing family-process capacity. Specifically, TPA contributes to local infrastructure enhancement to facilitate child human capital development while increasing targeted households’ utilization of medical services for their children and promoting educational inputs in children. Moreover, TPA substantially improves parent–child relationships, increases quality time spent together, and considerably reduces mothers’ depression in targeted households. A back-of-envelop calculation suggests that exposure to the TPA policy during childhood leads to a 0.562 increase in years of schooling and a 13.1 per cent increase in wages for adults in their twenties. [ABSTRACT FROM AUTHOR]

PCSK9 has been recognized as an efficient target for hyperlipidemia and related cardiovascular/cerebrovascular diseases. However, PCSK9 inhibitors in the clinic are all biological products, and no small molecules are available yet. In the current work, we discovered that the crude extract of Euphorbia esula ( E. esula ) promoted LDL uptake in vitro and then obtained 8 new and 12 known jatrophane diterpenoids by activity-guided isolation. After summarized their structure-activity relationship of PCSK9 inhibition, we selected compound 11 (C11) with potent activity and high abundance to investigate its mechanism and in vivo efficacy. Mechanistically, C11 bound with HNF1α to influence its nuclear distribution and subsequently inhibit PCSK9 transcription, thereby enhancing LDLR and promoting LDL uptake. Moreover, C11 demonstrated obvious lipid-lowering activity in HFD mouse model. In conclusion, we first revealed the novel application of E. esula in the discovery of a lipid-lowering candidate and highlighted the potential of C11 in the treatment of hyperlipidemia.

Whole mitochondrial genomes have been widely used in phylogenetic analysis, population genetics and biogeography studies. This study sequenced and characterized three complete mitochondrial genomes ( Dasyhippus peipingensis , Myrmeleotettix palpalis , Aeropedellus prominemarginis ) and determined their phylogenetic position in Acrididae. The length of the mitochondrial genomes ranged from 15,621-15,629 bp and composed of 13 PCGs, 2 rRNA, 22 tRNA genes and an AT control region. The arrangement and structure of the mitochondrial genomes were similar to those of other invertebrates. Comparative genomics revealed that the three mitochondrial genomes were highly conserved in terms of gene size, structure, and codon usage, all PCGs were purified selections with an ATN start codon and a TAN stop codon. All tRNAs could be folded into the typical clover-leaf structure, except tRNA Ser (AGN) that lacked a dihydrouridine (DHU) arm. Phylogenetic analysis based on 13 PCGs of 34 Acrididae species and seven outgroup species revealed that differences in the shape of antennae within the family Acrididae should be given less weight as a taxonomic character for higher-level classification. Moreover, the divergence time estimates indicates that in Gomphocerinae, the species with clubbed antennae were formed within the nearest 18 Mya, and Pacris xizangensis is more ancient., Competing Interests: The authors declare that they have no competing interests., (© 2023 Wang et al.)

Objective: To investigate the synergistic effect of oleanolic acid (OA) and cyclosporine A (CsA) on the survival of renal allografts in rats., Methods: Renal allograft transplantation was performed using BN rats as donors and LEW rats as recipients. Forty male LEW rats were randomized into 4 equal groups for interventions with DMSO-PBS (control), OA, CsA, or CsA+OA, starting from 1 day before transplantation. Serum creatinine levels were regularly examined, and the survival of rats were recorded. On day 5 after transplantation, CD4(+) and CD8(+) T-cell infiltration in the renal grafts was analyzed by immunohistochemistry; the concentrations of the proinflammatory cytokines (IL-1β, IFN-γ, IL-2, IL-4, and IL-17), anti-inflammatory cytokine IL-10 and chemokines (IP-10, MCP-1, MIP, and Mig) were analyzed with Luminex; the T-cell phenotypes (IFN-γ, IL-10, IL-4, and IL-17) were analyzed using ELISpot., Results: In OA+CsA group, renal allograft survival was markedly prolonged and CD4(+) and CD8(+) T cell infiltration in the graft significantly decreased as compared to other groups. A significant decrease in IL-2 was observed in OA group and OA+CsA group, especially the latter. Compared with the control group, all the 3 treated groups showed significantly decreased IL-1β, IP-10 and MCP-1, increased IL-10 levels, decreased percentages of T cells secreting IFN-γ, IL-4 and IL-17, and increased percentage of T cells secreting IL-10. The increments of serum IL-10 level and T cell percentage were more prominent in OA+CsA group than in the other two intervention groups., Conclusions: OA and CsA synergistically ameliorate renal graft rejection and inflammation and promote allograft survival and function in rats.