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We introduce aggregate transmission shocks to an epidemic model and link firm valuations to infections via an asset pricing framework with vaccines. Infections lower earnings growth but firms can mitigate damages. We estimate a large reproduction number |${\mathcal R}_0$| and transmission volatility for COVID-19. Using these estimates, we quantify the bias of deterministic approximations based on |${\mathcal R}_0$|⁠. Our model generates predictions consistent with the data: unexpected infection resurgence, nonmonotonic mitigation policies, and higher price-to-earnings ratios during a pandemic. Valuations would be significantly lower absent mitigation and a high vaccine arrival rate. [ABSTRACT FROM AUTHOR]

Optimising advanced oxidation processes (AOPs) by creating oxygen vacancies (OVs) on metal oxides via doping with different ions to improve catalyst activity is currently a significant research field. OVs produced by doping have the potential to substantially reduce the reaction energy barrier, and impact the reaction products with high selectivity. However, there is currently a lack of reviews on the utilization of dopant ions to induce OVs and the application of dopant-induced OVs in AOPs. This paper provides a systematic overview of the selection of dopant ions for the construction of OVs by doping. Additionally, we present two theoretical explanations highlighting the ability of doping to obtain OVs, explaining how doping can be used to design catalysts with ample OVs. Next, we methodically illustrate the kinetic and thermodynamic interactions between OVs and dopant ions. We also discuss the direct and indirect destruction of OVs by environmental factors that influence dopant elements in AOPs. Finally, the paper concludes with a detailed account of the application of OVs induced by doping in typical advanced oxidation techniques, such as Fenton-like oxidation, activated persulfate oxidation, catalytic ozonation, photocatalysis and electrochemical oxidation. Additionally, potential avenues of future research are suggested. [ABSTRACT FROM AUTHOR]

Guilu-Erxian-Glue (GLEXG) is a traditional Chinese formula used to improve male reproductive dysfunction. To investigate the ferroptosis resistance of GLEXG in the improvement of semen quality in the oligoasthenospermia (OAS) rat model. Male Sprague-Dawley (SD) rats were administered Tripterygium wilfordii polyglycoside, a compound extracted from Tripterygium wilfordii Hook F. (Celastraceae), at a dose of 40 mg/kg/day, to establish an OAS model. Fifty-four SD rats were randomly divided into six groups: sham, model, low-dose GLEXG (GLEXGL, 0.25 g/kg/day), moderate-dose GLEXG (GLEXGM, 0.50 g/kg/day), high-dose GLEXG (GLEXGH, 1.00 g/kg/day) and vitamin E (0.01 g/kg/day) group. The semen quality, structure and function of sperm mitochondria, histopathology, levels of oxidative stress and iron, and mRNA levels and protein expression in the Keap1/Nrf2/GPX4 pathway, were analyzed. Compared with the model group, GLEXGH significantly improved sperm concentration (35.73 ± 15.42 vs. 17.40 ± 4.12, p < 0.05) and motility (58.59 ± 11.06 vs. 28.59 ± 9.42, p < 0.001), and mitigated testicular histopathology. Moreover, GLEXGH markedly reduced the ROS level (5684.28 ± 1345.47 vs. 15500.44 ± 2307.39, p < 0.001) and increased the GPX4 level (48.53 ± 10.78 vs. 23.14 ± 11.04, p < 0.01), decreased the ferrous iron level (36.31 ± 3.66 vs. 48.64 ± 7.74, p < 0.05), and rescued sperm mitochondrial morphology and potential via activating the Keap1/Nrf2/GPX4 pathway. Ferroptosis resistance from GLEXG might be driven by activation of the Keap1/Nrf2/GPX4 pathway. Targeting ferroptosis is a novel approach for OAS therapy. [ABSTRACT FROM AUTHOR]

The naturally scarce eupholathone-type euphornin E (1) was efficiently prepared from abundant lathyrane-type Euphorbia factor L1via a visible-light-induced Sc(OTf)3-catalyzed tandem process. Eupholathones 2 and 3 were also smoothly obtained by changing the reaction solvent. This route provides a convenient method for easily constructing scarce eupholathone- from lathyrane-type Euphorbia diterpenes, and confirms the biogenetic relationship between them from a chemical standpoint. Notably, compound 1 exhibited good anti-HIV activity. [ABSTRACT FROM AUTHOR]