This is a systematic theoretical investigation on all the possible light emitters of firefly using a multireference method. Six chemical forms of oxyluciferin (OxyLH2) molecules/anions were studied by a multistate complete active space second-order perturbation (MS-CASPT2) method in vacuum and dimethyl sulfoxide. The calculated results and subsequent analysis excluded enol-OxyLH2, keto-OxyLH2, and enolate-OxyLH(-) as possible light emitters. The remaining three candidates, phenolate-enol-OxyLH(-), phenolate-keto-OxyLH(-), and OxyL(2-), were further investigated in protein by a MS-CASPT2/molecular mechanics (MM) study to explain the natural bioluminescence of firefly. By comparison of the MS-CASPT2/MM calculated results of phenolate-enol-OxyLH(-), phenolate-keto-OxyLH(-), and OxyL(2-) with the experimental observation and detailed analysis, we concluded that the direct decomposition excited-state product of firefly dioxetanone in vivo and the only light emitter of firefly in natural bioluminescence is the first singlet excited state (S1) of phenolate-keto-OxyLH(-).
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Sci Rep
January 2025
China Coal Shanxi China Resources Liansheng Energy Investment Co., LTD, Lvliang, 033000, China.
Bolt support improves the stress state of the surrounding rock and forms an integral bearing structure inside the anchored surrounding rock. Therefore, it is of theoretical significance and practical application value to systematically study the mechanical mechanism and bearing characteristics of the anchorage composite carrier and elucidate the interaction mechanism between the bearing effect of the anchorage composite carrier and the stability of the roadway surrounding rock. In this paper, a mechanical model for the anchorage composite carrier is meticulously constructed through a fusion of theoretical analysis and advanced numerical simulation techniques.
View Article and Find Full Text PDFFood Chem
January 2025
Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China. Electronic address:
Reductions in polycyclic aromatic hydrocarbon (PAH) concentrations have been observed during frying. However, transformation mechanisms of PAHs remain unclear. We hypothesize that PAHs may be oxidized into oxygenated polycyclic aromatic hydrocarbons (OPAHs) and other derivatives during frying.
View Article and Find Full Text PDFPharmacoeconomics
January 2025
Belgian Health Care Knowledge Centre, Brussels, Belgium.
Background: Forecasting future public pharmaceutical expenditure is a challenge for healthcare payers, particularly owing to the unpredictability of new market introductions and their economic impact. No best-practice forecasting methods have been established so far. The literature distinguishes between the top-down approach, based on historical trends, and the bottom-up approach, using a combination of historical and horizon scanning data.
View Article and Find Full Text PDFInorg Chem
January 2025
Key Laboratory of Green and Precise Synthetic Chemistry and Applications, Ministry of Education, Huaibei Normal University, Huaibei, Anhui 235000, P. R. China.
Improving catalytic performance by controlling the microstructure of materials has become a hot topic in the field of photocatalysis, such as the surface defect site, multistage layered morphology, and exposed crystal surface. Due to the differences in the metal atomic radius (Mn and Cd) and solubility product constant (MnS and CdS), Mn defect easily occurred in the S/MnCdS (S/0.4MCS) composite.
View Article and Find Full Text PDFNutrients
December 2024
Engineering Research Center of Chinese Ministry of Education for Edible and Medicinal Fungi, Jilin Agricultural University, Changchun 130118, China.
Background: Atherosclerosis, a persistent inflammatory disease marked by the presence of atherosclerotic plaques or fibrous plaques, is a significant contributor to the onset of the development of cardiovascular disease. Berk contains various active ingredients that have anti-inflammatory, antioxidant, and hypolipidemic properties. Nevertheless, the potential effects of on atherosclerosis have not been systematically reported.
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