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Through-thickness corrosion homogeneity of stabilized AA5083 alloy thick plate was investigated. For the as-received stabilized plates, no differences in corrosion behavior are evident in the specimens from different sampling positions along the thickness direction. However, in the plates after sensitization, the specimen from the surface position (T/10, SP) exhibits the highest degree of sensitization (DoS) and stress corrosion cracking (SCC) susceptibility, indicating the through-thickness corrosion inhomogeneity. Compared with interlayer position (3T/10, IP) and center position (T/2, CP), the higher grain stored energy and richer high angle grain boundaries (HAGBs) in SP specimens promote the formation of β phases (Al3Mg2) during the sensitization process. It results in a high coverage of β phases in the SP specimen and therefore induces severe corrosion.

α-mangostin, a polyphenol xanthone derivative, was mainly isolated from pericarps of the mangosteen fruit (Garcinia mangostana L.). In present investigation, a series of derivatives were designed, synthesised and evaluated in vitro for their inhibitory activity of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Among the synthesised xanthones, compounds 1, 9, 13 and 16 showed AChE selective inhibitory activity, 15 was a BuChE selective inhibitor while 2, 3, 5, 6, 7, 12 and 14 were dual inhibitors. The most potent inhibitor of AChE was 16 while 5 was the most potent inhibitor of BuChE with IC50 values of 5.26 μM and 7.55 μM respectively. [ABSTRACT FROM AUTHOR]

Cyclic hibernation bouts in Daurian ground squirrels (Spermophilus dauricus) lead to repeated suppression and recovery of mitochondrial respiratory function across multiple organs, potentially impacting reactive oxygen species (ROS) dynamics. The Harderian gland (HG) plays an important role in endocrine regulation through porphyrin secretion. However, the influence of hibernation on oxidative pressure and associated antioxidant pathways in the HG remains inadequately understood. In the current study, we investigated the morphological changes, secretory activity, ROS levels, and underlying mechanisms in the HG of Daurian ground squirrels at distinct circannual stages of hibernation. Results indicated that: (1) Protoporphyrin levels in the HG increased during hibernation compared to the summer active (SA) phase, with a reduction in acinar lumen during torpor, potentially related to hibernation in a low-light environment. (2) Hydrogen peroxide (H 2 O 2 ) and malondialdehyde (MDA) content during hibernation and post-hibernation (POST) did not exceed the levels observed in SA, indicating that the HG effectively mitigated oxidative pressure and lipid peroxidation during these periods. (3) Superoxide dismutase (SOD) activity increased while glutathione peroxidase (GPx) activity decreased during Inter-bout arousal (IBA) compared to both SA and torpor, although total antioxidant capacity (T-AOC) remained stable across all stages. (4) Overall fluorescent intensity of nuclear factor erythroid 2-related factor 2 (Nrf2) and Kelch-like ECH-associated protein 1 (Keap1) was significantly lower than in SA. These findings demonstrate that the HG in Daurian ground squirrels maintains a favorable oxidative status through the regulation of antioxidant enzyme activities during hibernation and even post-hibernation., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)