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Silicone rubber foam is a significant structural material in specific systems. It works effectively under mechanical and complex environmental loads such as thermal, oxygen, irradiation, and so on. Previous studies have showed that the silicone rubber foam ages under complex conditions such as heat, oxygen, irradiation, and mechanical, which leads to the deterioration of its material properties. The aging mechanism of porous silicon rubber foam under the combination of thermal oxygen and irradiation is more complicated in contrast to the ordinary thermal degradation of rubber. It has always been challenging to predict the service life of silicon rubber foam accurately. The development of new experimental techniques for enhancing numerical modeling ability and establishing a theoretical multi-field aging model has been a key concern. Further, it is essential for predicting the life of silicon rubber foam and guiding performance evaluation. In this study, the research results of accelerated the aging of silicon rubber foam have been presented, primarily in three aspects including thermo-oxygen aging, radiation aging, and multi-field speed-up aging. Furthermore, the current research progress and latest developments in this field of study have been summarized.

Tanshinone IIA is an extract of Salvia miltiorrhiza Bunge (Labiatae) used to treat cardiovascular disorders. It shows potential anticonvulsant and cognition-protective properties. We investigated the mechanism of tanshinone IIA on antiepileptic and cognition-protective effects in the model of epileptic rats. Lithium chloride (LiCl)-pilocarpine-induced epileptic Wistar rats were randomly assigned to the following groups (n = 12): control (blank), model, sodium valproate (VPA, 189 mg/kg/d, positive control), tanshinone IIA low dose (TS IIA-L, 10 mg/kg/d), medium dose (TS IIA-M, 20 mg/kg/d) and high dose (TS IIA-H, 30 mg/kg/d). Then, epileptic behavioural observations, Morris water maze test, Timm staining, transmission electron microscopy, immunofluorescence staining, western blotting and RT-qPCR were measured. Compared with the model group, tanshinone IIA reduced the frequency and severity of seizures, improved cognitive impairment, and inhibited hippocampal mossy fibre sprouting score (TS IIA-M 1.50 ± 0.22, TS IIA-H 1.17 ± 0.31 vs. model 2.83 ± 0.31), as well as improved the ultrastructural disorder. Tanshinone IIA increased levels of synapse-associated proteins synaptophysin (SYN) and postsynaptic dense substance 95 (PSD-95) (SYN: TS IIA 28.82 ± 2.51, 33.18 ± 2.89, 37.29 ± 1.69 vs. model 20.23 ± 3.96; PSD-95: TS IIA 23.10 ± 0.91, 26.82 ± 1.41, 27.00 ± 0.80 vs. model 18.28 ± 1.01). Tanshinone IIA shows antiepileptic and cognitive function-improving effects, primarily via regulating synaptic plasticity. This research generates a theoretical foundation for future research on potential clinical applications for tanshinone IIA. [ABSTRACT FROM AUTHOR]

Human angiotensin-converting enzyme 2 (hACE2) is the primary receptor for cellular entry of SARS-CoV-2 into human host cells. hACE2 is heavily glycosylated and glycans on the receptor may play a role in viral binding. Thus, comprehensive characterization of hACE2 glycosylation could aid our understanding of interactions between the receptor and SARS-CoV-2 spike (S) protein, as well as provide a basis for the development of therapeutic drugs targeting this crucial interaction. Herein, 138 N-glycan compositions were identified, most of which are complex-type N-glycans, from seven N-glycosites of hACE2. Among them, 67% contain at least one sialic acid residue. At the level of glycopeptides, the overall quantification of sialylated glycan isomers observed on the sites N322 and N546 have a higher degree of NeuAc (α2–3)Gal (over 80.3%) than that of other N-glycosites (35.6–71.0%). In terms of O-glycans, 69 glycan compositions from 12 O-glycosites were identified, and especially, the C-terminus of hACE2 is heavily O-glycosylated. The terminal sialic acid linkage type of H1N1S1 and H1N1S2 are covered highly with α2,3-sialic acid. These findings could aid the investigation of the interaction between SARS-CoV-2 and human host cells. [ABSTRACT FROM AUTHOR]

Exogenous melatonin (MT) regulates plant growth and mitigates stress in response to stress. To analyze the machinery of exogenous melatonin, which improves salt and alkaline tolerance in oats, MT's function was identified in the oat seed germination stage in our previous study. In this study, morphogenesis, photosynthetic physiology, hormone levels, and ion homeostasis were evaluated using the same MT treatment concentration. The results revealed that compared to the S45 treatment, the 100 μmol·L−1 MT treatment efficiently increased the seedling height and main root length of oat seedlings; promoted secondary root development; enhanced the root volume and root surface area; maintained a higher photosynthetic pigment content (carotenoids; chlorophyll a; chlorophyll b); raised the leaf photosynthetic rate (Pn), intercellular CO2 concentration (Ci), conductance to H2O (Gs), and transpiration rate (Tr); enhanced the light energy absorption and conversion of leaves; increased the leaf GA3, Tryptamine (TAM), and IAA contents; and decreased ABA levels. Hierarchical cluster analysis revealed that MT treatment also increased the contents of P, K, Ca, Mn, Cu, Mg, Fe, Zn, Mo, Cd, Al, Se, Ni, Co, and Ti; decreased the Na/K ratio; and maintained cellular ionic homeostasis in oat seedlings under saline–alkali stress, as compared with the untreated group. These findings showed that MT treatment enhanced the adaptation of oat to saline–alkali stress through regulating the physiological process of seedling growth. This suggests that MT plays a different role in improving saline–alkali tolerance in the germination and seedling stages of oat. [ABSTRACT FROM AUTHOR]