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Objective To evaluate the inflammation of perirenal adipose tissue induced by high-fat diet in C57BL/6J mice. Methods Mice were randomly divided into normal diet group (control group, n=6) and high-fat diet group (HFD group, n=6). The mRNA expression of TNF-α, CD11c, IL-1β, IL-10, TGF-β1, CD206 in perirenal adipocytes were detected by RT-qPCR. The expressions of F4/80, CD68 and LCA in perirenal adipose tissue and renal parenchyma were detected by immunohistochemistry method. Results Compared with the control group, the mRNA expression by TNF-α and IL-1β in perirenal adipose tissue of mice in HFD group was increased(P＜0.05); The expression of F4/80, CD68 and LCA in perirenal fat increased in HFD group(P＜0.05). Conclusions High-fat diet induces inflammation in perirenal adipose tissue of C57BL/6J mice.

Searching the global minimum (GM) structures of metal clusters is of great importance in cluster science. Very recently, the global optimization method based on deep neural network combined with transfer learning (DNN-TL) was developed to improve the efficiency of optimizing the GM structures of metal clusters by greatly reducing the number of samples to train the DNN. Aiming to further enhance the sampling efficiency of the potential energy surface and the global search ability of the DNN-TL method, herein, an advanced global optimization method by embedding genetic algorithm (GA) into the DNN-TL method (DNN-TL-GA) is proposed. In the case of the global optimization of Ptn (n=9–15) clusters, the DNN-TL-GA method requires only a half number of samples at most with respect to the DNN-TL method to find the GM structures. Meanwhile, the DNN-TL-GA method saves about 70%-80% of computational costs, suggesting the significant improved efficiency of global search ability. There are much more samples distributed in the area of the potential energy surface with low energies for DNN-TL-GA (25% for Pt14) than for DNN-TL (<1% for Pt14). The success of the DNNTL-GA method for global optimization is evidenced by finding unprecedented GM structures of Pt16 and Pt17 clusters. [ABSTRACT FROM AUTHOR]

A fundamental understanding of the exact structural characteristics and reaction mechanisms of interface active sites is vital to engineering an energetic metal–support boundary in heterogeneous catalysis. Herein, benefiting from a newly developed high-temperature ion trap reactor, the reverse water–gas shift (RWGS) (CO2 + H2 → CO + H2O) catalyzed by a series of compositionally and structurally well-defined RhnVO3,4− (n = 3–7) clusters were identified under variable temperatures (298–773 K). It is discovered that the Rh5–7VO3,4− clusters can function more effectively to drive RWGS at relatively low temperatures. The experimentally observed size-dependent catalytic behavior was rationalized by quantum-chemical calculations; the framework of RhnVO3,4− is constructed by depositing the Rhn clusters on the VO3,4 "support", and a sandwiched base–acid–base [Rhout−–Rhin+–VO3,4−; Rhout and Rhin represent the outer and inner Rh atoms, respectively] feature in Rh5–7VO3,4− governs the adsorption and activation of reactants as well as the facile desorption of the products. In contrast, isolated Rh5–7− clusters without the electronic modification of the VO3,4 "support" can only catalyze RWGS under relatively high-temperature conditions. [ABSTRACT FROM AUTHOR]

Nitrogen (N2) fixation is a challenging task for chemists. Adsorption of N2 on transition metal (TM) sites has been identified as a prerequisite for activating the very stable N≡N triple bond in both industrial and biological processes. The importance of π back-donation (filled orbitals of TM → π* orbitals of N2) between metal sites and N2 has been well elucidated while the role of another classic orbital interaction, namely σ donation (σ orbitals of N2 → empty orbitals of TM), remains ambiguous. Herein, the size-dependent reactivity of trinuclear rhodium deuteride cluster anions Rh3Dn− (n = 0–3) toward N2 adsorption in the gas phase was investigated experimentally and theoretically. A reverse relationship that higher electron-donating ability of clusters corresponds to lower N2 adsorption reactivity was experimentally observed, which is uncommon in N2 activation by gas-phase species. Theoretical analysis revealed that the σ donation rather than the π back-donation plays a predominant role in the adsorption complexes Rh3DnN2− and the enhanced reactivity upon D addition is ascribed to the lowered energy levels of active orbitals in Rh3Dn− as n increases. This study provides the first experimental evidence to declare the important role of σ donation and new clues for the design of reactive metal species in nitrogen fixation. [ABSTRACT FROM AUTHOR]

BACKGROUND: Phenolic endocrine‐disrupting chemicals (EDCs) are widespread and easily ingested through the food chain. They pose a serious threat to human health. Magnetic solid‐phase extraction (MSPE) is an effective sample pre‐treatment technology to determine traces of phenolic EDCs. RESULTS: Magnetic covalent organic framework (COF) (Fe3O4@COF) nanospheres were prepared and characterized. The efficient and selective extraction of phenolic EDCs relies on a large specific surface and the inherent porosity of COFs and hydrogen bonding, π–π, and hydrophobic interactions between COF shells and phenolic EDCs. Under optimal conditions, the proposed magnetic solid‐phase extraction‐high‐performance liquid chromatography–ultra violet (MSPE‐HPLC‐UV) based on the metallic covalent organic framework method for phenolic EDCs shows good linearities (0.002–6 μg mL−1), with R2 of 0.995 or higher, and low limits of detection (6–1.200 ng mL−1). CONCLUSION: Magnetic covalent organic frameworks (Fe3O4@COFs) with good MSPE performance for phenolic EDCs were synthesized by the solvothermal method. The magnetic covalent organic framework‐based MSPE‐HPLC‐UV method was applied successfully to determine phenolic EDCs in beverage and water samples with satisfactory recoveries (90.200%–123%) and relative standard deviations (2.100%–12.100%). © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]