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Different bimetallic platinum and bismuth catalysts supported on melamine‐modified activated carbon (AC) are designed by a co‐impregnation method. Through controlling the activation temperatures of the melamine−AC mixture, a series of N‐doped and C3N4‐modified AC (N−AC and C3N4−AC) are prepared. Combined powder X‐ray diffractions, X‐ray photoelectron spectroscopic, and high‐angle annual dark‐field scanning transmission electron microscopic studies demonstrate that the introduction of C3N4 favors the formation of PtBi alloy and leads to increased particle sizes in comparison to the pristine and N‐doped AC‐supported bimetallics. The catalytic performance of the developed catalysts is evaluated in the oxidation of n‐heptanol oxidation in a batch mode using O2 as the oxidant. PtBi/C3N4−AC exhibits significantly boosted activity as well as selectivity to heptanoic acid as compared with the other catalysts. A high yield of heptanoic acid of 69 % can be achieved under the optimized reaction conditions. Furthermore, our work points to the PtBi alloy as the most active sites for the alcohol oxidation. Catalyst deactivation occurs in the cycling tests, mainly due to the collapse of the alloy phase and likely the decrease in particle sizes. [ABSTRACT FROM AUTHOR]

During ageing, adult stem cells' regenerative properties decline, as they undergo replicative senescence and lose both their proliferative and differentiation capacities. In contrast, embryonic and foetal progenitors typically possess heightened proliferative capacities and manifest a more robust regenerative response upon injury and transplantation, despite undergoing many rounds of mitosis. How embryonic and foetal progenitors delay senescence and maintain their proliferative and differentiation capacities after numerous rounds of mitosis, remains unknown. It is also unclear if defined embryonic factors can rejuvenate adult progenitors to confer extended proliferative and differentiation capacities, without reprogramming their lineage‐specific fates or inducing oncogenic transformation. Here, we report that a minimal combination of LIN28A, TERT, and sh‐p53 (LTS), all of which are tightly regulated and play important roles during embryonic development, can delay senescence in adult muscle progenitors. LTS muscle progenitors showed an extended proliferative capacity, maintained a normal karyotype, underwent myogenesis normally, and did not manifest tumorigenesis nor aberrations in lineage differentiation, even in late passages. LTS treatment promoted self‐renewal and rescued the pro‐senescence phenotype of aged cachexia patients' muscle progenitors, and promoted their engraftment for skeletal muscle regeneration in vivo. When we examined the mechanistic basis for LIN28A's role in the LTS minimum combo, let‐7 microRNA suppression could not fully explain how LIN28A promoted muscle progenitor self‐renewal. Instead, LIN28A was promoting the translation of oxidative phosphorylation mRNAs in adult muscle progenitors to optimize mitochondrial reactive oxygen species (mtROS) and mitohormetic signalling. Optimized mtROS induced a variety of mitohormetic stress responses, including the hypoxic response for metabolic damage, the unfolded protein response for protein damage, and the p53 response for DNA damage. Perturbation of mtROS levels specifically abrogated the LIN28A‐driven hypoxic response in Hypoxia Inducible Factor‐1α (HIF1α) and glycolysis, and thus LTS progenitor self‐renewal, without affecting normal or TS progenitors. Our findings connect embryonically regulated factors to mitohormesis and progenitor rejuvenation, with implications for ageing‐related muscle degeneration. [ABSTRACT FROM AUTHOR]

The shape of the carriers has a profound impact on the catalytic performance of metal‐supported catalysts. Herein, ZrO2 of different shapes (nanorods‐like, spherical or irregular nanoparticles, demoted as RZ, SPZ, and IPZ, respectively) are adopted to disperse Ni species to assess the shape effects on the catalytic performance in dry reforming of methane. To this end, the fresh and spent catalysts are thoroughly characterized by multiple techniques including N2 sorption, powder X‐ray diffraction, temperature‐programmed reduction with H2, thermogravimetric analyses, transmission electron microscopy, Raman and X‐ray photoelectron spectroscopies. It is revealed that the reducibility of NiO species follows the orders of Ni/RZ

BACKGROUND: Pesticide contamination in oil crops and processed products is an important food safety concern. The study was aimed to investigate the pesticide residue changes in press processing of peanut oil and frying of chips. RESULTS: Five pesticides – chlorpyrifos, deltamethrin, methoxyfenozide, azoxystrobin and propargite – which are often applied during growth period in peanut plants, were selected to investigate their residue changes in cold press processing of peanut oil and frying of potato chips. Results showed that the residues of the five pesticides were decreased by 3.1–42.6% during air‐drying before oil pressing. The residues of chlorpyrifos, deltamethrin, methoxyfenozide and propargite in peanut oil were 2.05–3.63 times higher than that in peanut meal after cold pressing of the oil, except for azoxystrobin having a slightly lower residue in peanut oil, with 0.92 times that in peanut meal. The processing factors of the five pesticides in peanut oil ranged from 1.17 to 2.73 and were highly related to the log Kow of the pesticides. The higher the log Kow, the more easily was the pesticide partitioned in the peanut oil. Besides, as frying time increase during preparation of chips, the concentration of pesticides in peanut oil decreased gradually by 6.7–22.1% compared to the first frying. In addition, 0.47–11.06% of the pesticides were transferred to the chips through frying with contaminated oil. CONCLUSION: This is first report showing that pesticides can transfer from contaminated oil to chips. There exists a potential dietary health risk by using pesticide‐contaminated oil for frying chips. This work could provide basic data for accurate dietary risk assessment of pesticide residues in peanut oil and its frying products. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]