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Metal-catalysed reactions are often hypothesized to proceed on bifunctional active sites, whereby colocalized reactive species facilitate distinct elementary steps in a catalytic cycle1–8. Bifunctional active sites have been established on homogeneous binuclear organometallic catalysts9–11. Empirical evidence exists for bifunctional active sites on supported metal catalysts, for example, at metal–oxide support interfaces2,6,7,12. However, elucidating bifunctional reaction mechanisms on supported metal catalysts is challenging due to the distribution of potential active-site structures, their dynamic reconstruction and required non-mean-field kinetic descriptions7,12,13. We overcome these limitations by synthesizing supported, atomically dispersed rhodium–tungsten oxide (Rh-WOx) pair site catalysts. The relative simplicity of the pair site structure and sufficient description by mean-field modelling enable correlation of the experimental kinetics with first principles-based microkinetic simulations. The Rh-WOx pair sites catalyse ethylene hydroformylation through a bifunctional mechanism involving Rh-assisted WOx reduction, transfer of ethylene from WOx to Rh and H2 dissociation at the Rh-WOx interface. The pair sites exhibited >95% selectivity at a product formation rate of 0.1 gpropanal cm−3 h−1 in gas-phase ethylene hydroformylation. Our results demonstrate that oxide-supported pair sites can enable bifunctional reaction mechanisms with high activity and selectivity for reactions that are performed in industry using homogeneous catalysts.Catalysts consisting of oxide-supported pair sites can enable bifunctional reaction mechanisms with high activity and selectivity for reactions and so overcome the limitations in industry imposed by the use of homogeneous catalysts. [ABSTRACT FROM AUTHOR]

An orientational dependence on the interfacial reaction between aluminum and (010), (001), and ( 2 ̄ 01) β-Ga2O3 substrates is addressed. Electron microscopy and x-ray diffraction were used to assess the interface crystallinity, thickness, and chemical composition of the interfacial layers. At the interface, amorphous aluminum oxide is observed in all three samples with a thicknesses of 3.5 nm for (010) β-Ga2O3 and 2 nm for (001) β-Ga2O3 and ( 2 ̄ 01) β-Ga2O3. Aluminum oxide is formed at the interface as a result of a chemical reaction that reduces the Ga2O3 surface when aluminum is deposited. We propose that in Al on (010) β-Ga2O3, in which the thickest interfacial oxide layer is observed, diffusional pathways of consecutive octahedral Ga sites perpendicular to the interface promote increased interdiffusion in the out-of-plane direction. In contrast, the (001) β-Ga2O3 and ( 2 ̄ 01) β-Ga2O3 substrates exhibit alternating rows of tetrahedral and octahedral Ga sites parallel to the interface, where the rows of tetrahedral Ga sites act as increased energy barriers that impede interdiffusion of Al and β-Ga2O3. The orientational dependence of metal-oxide interlayers in β-Ga2O3 can impact electronic and thermal transport, pointing to the importance of understanding the impact of β-Ga2O3 orientation on interfacial properties. [ABSTRACT FROM AUTHOR]

AbstractCurrent studies have clearly shown that aristolochic acid (AA) exposure can induce a variety of diseases, such as kidney disease, liver cancer, and urinary tract cancer (UTC). However, no studies have systematically analyzed and integrated these results. Therefore, we aimed to elucidate the association between AA exposure and the risk of safety outcomes for AA-related overall disease and different types of disease it causes. We conducted an exhaustive search of PubMed, EMBASE, Web of Science, and the Cochrane Library for relevant material up to April 2024. For AA-related overall disease, AA exposure was significantly associated with an increased incidence of AA-related overall disease (OR: 1.289, 95% CI: 1.183 − 1.404). For different types of disease, AA exposure was significantly associated with increased incidence of kidney disease (OR: 1.279, 95% CI: 1.029 − 1.590), UTC (OR: 1.842, 95% CI: 1.376 − 2.465) and liver cancer (OR: 1.146, 95% CI: 1.040 − 1.262). No significant association was found between AA exposure and the incidence of brain disease (OR: 1.161, 95% CI: 0.989 − 1.362). This study systematically analyzed various safety outcomes associated with AA exposure to provide a solid scientific basis for future prevention strategies and clinical management. [ABSTRACT FROM AUTHOR]

Clinical evidence for early identification and diagnosis of liver cirrhosis (LC) caused by different types of liver disease is limited. We investigated this topic through a meta-analysis of quantitative metabolomics. Four databases were searched until October 31, 2022 for studies comparing metabolite levels between patients with different types of liver disease and control individuals. A random-effects model was applied for the meta-analysis. This study included 55 studies with 8266 clinical participants, covering 348 metabolites. In LC related to drug-induced liver injury (DILI), hepatitis B virus (HBV) infection, and non-alcoholic fatty liver disease (NAFLD), the primary bile acid biosynthesis (taurocholic acid: SMD, 1.08[0.81, 1.35]; P < 0.00001; glycocholic acid: SMD, 1.35[1.07, 1.62]; P < 0.00001; taurochenodeoxycholic acid: SMD, 1.36[0.94, 1.78]; P < 0.00001; glycochenodeoxycholic acid: SMD, 1.49[0.93, 2.06]; P < 0.00001), proline and arginine (l -proline: SMD, 1.06[0.53, 1.58]; P < 0.0001; hydroxyproline: SMD, 0.81[0.30, 1.33]; P = 0.002), and fatty acid biosynthesis (palmitic acid: SMD, 0.44[0.21, 0.67]; P = 0.0002; oleic acid: SMD, 0.46[0.19, 0.73]; P = 0.0008; stearic acid: SMD, 0.37[0.07, 0.68]; P = 0.02) metabolic pathways were significantly altered. We identified key biomarkers and metabolic characteristics for distinguishing and identifying LC related to different types of liver disease, providing a new perspective for early diagnosis, disease monitoring, and precise treatment. • The metabolic characteristics of different liver diseases were quantitatively evaluated. • The metabolic pathways of cirrhosis related to different liver diseases have been clarified. • Key biomarkers of cirrhosis related to different liver diseases have been identified. [ABSTRACT FROM AUTHOR]

• A systematic review of mycotoxin contamination in medicinal plants was conducted. • The prevalence and concentration of mycotoxins were analyzed through meta-analysis. • The dietary exposure risk of mycotoxins was evaluated by the point assessment method. • Aflatoxins and ochratoxin A indicated risk in diverse traditional Chinese medicines. • Thus, the severity of mycotoxin contamination in medicinal plants should be reduced. Mycotoxins have been reported to be present in medicinal plants. With the growing usage of medicinal plants, contamination of mycotoxins has emerged as one of the biggest threats to global food hygiene and ecological environment, posing a severe threat to human health. This study aimed to determine the mycotoxin prevalence and levels in medicinal plants and conduct a risk assessment by conducting a systematic review and meta-analysis. A thorough search on Web of Science and PubMed was conducted for the last decade, resulting in 54 studies (meeting the inclusion criteria) with 2829 data items that were included in the meta-analysis. The combined prevalence of mycotoxins in medicinal plants was 1.7% (95% confidence interval, CI = 1.1% – 2.4%), with a mean mycotoxin concentration in medicinal plants of 3.551 µg/kg (95% CI = 3.461 – 3.641 µg/kg). Risk assessment results indicated that aflatoxins and ochratoxin A found in several medicinal plants posed a health risk to humans; additionally, emerging enniatins exhibited possible health risks. Therefore, the study underlines the need for establishing stringent control measures to reduce the severity of mycotoxin contamination in medicinal plants. [Display omitted] [ABSTRACT FROM AUTHOR]

Closing the anthropogenic carbon cycle by converting CO2 into reusable chemicals is an attractive solution to mitigate rising concentrations of CO2 in the atmosphere. Herein, we prepared Ni metal catalysts ranging in size from single atoms to over 100 nm and distributed them across N‐doped carbon substrates which were obtained from converted zeolitic imidazolate frameworks (ZIF). The results show variance in CO2 reduction performance with variance in Ni metal size. Ni single atoms demonstrate a superior Faradaic efficiency (FE) for CO selectivity (ca. 97 % at −0.8 V vs. RHE), while results for 4.1 nm Ni nanoparticles are slightly lower (ca. 93 %). Further increase the Ni particle size to 37.2 nm allows the H2 evolution reaction (HER) to compete with the CO2 reduction reaction (CO2RR). The FE towards CO production decreases to under 30 % and HER efficiency increase to over 70 %. These results show a size‐dependent CO2 reduction for various sizes of Ni metal catalysts. [ABSTRACT FROM AUTHOR]