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Summary: Half-metallic materials are widely used as spintronic devices such as electrodes, magnetic tunneling junction, and giant magnetoresistance. In this work, we have systematically investigated the structural stability, Gilbert damping, electronic structure, and magnetism together with exchange interactions and Curie temperatures for Mn2TaAl and Mn2WAl alloys. Initially, we estimate their structural stability and offer possible phase synthesis. Subsequently, the Gilbert damping parameters calculated by the linear response theory are used to assess their response speed as spintronic materials. Furthermore, the Mn2TaAl and Mn2WAl are predicted to be half-metallic and nearly half-metallic ferrimagnets and their total magnetic moments obey the Mt = Zt-18 rule. Accordingly, their Curie temperatures for Mn2TaAl and Mn2WAl are also evaluated by the mean-field approximation. Finally, their thermodynamic parameters within 0∼600 K and thermoelectric properties within 200∼900 K are discussed. Overall, our research for Mn2TaAl and Mn2WAl alloys might provide some valuable clues for their application in spintronic devices.

Background and aims“Astringent seed” is a type of abortive seed frequently observed in Chinese fir (Cunninghamia lanceolata). It is widely recognized but poorly understood for its underlying causes. This study investigates the potential of astringent seeds to alleviate the toxic effects of active aluminum ions.MethodsThis study involved treating seeds and seedlings with two distinct concentrations of astringent seeds water extracts under the aluminum ion stress. Then the germination of seeds and growth of seedlings were evaluated and compared.ResultsUnder aluminum stress, both seed germination and seedling growth were notably inhibited. Treatment with a low-concentration of the extract significantly alleviated this inhibition. Root elongation in the seedlings increased by 36.95% compared to the control group, and the aluminum ion accumulation at the root tips was reduced by 38.89% relative to the aluminum-stressed group. This treatment also normalized the levels of malondialdehyde (MDA) in the roots and leaves, enhanced the activities of antioxidative enzymes such as superoxide dismutase (SOD) and catalase (CAT), and restored the levels of endogenous hormones including gibberellin (GA3), indole-3-acetic acid (IAA), methyl jasmonate (Ja-ME), and abscisic acid (ABA). Furthermore, the low-concentration of the extract positively impacted the disorganized chloroplast structures. In contrast, a high-concentration of the extract failed to revert most of these stress indicators.ConclusionLow concentrations of astringent seed water extract effectively alleviate the inhibitory effects of aluminum ions on seed and seedling. This implies that in natural environments, the proximity of healthy seeds to astringent seeds could potentially enhance their growth.

Objective To observe the injury of intestinal mucosal barrier and the expression of autophagy protein in colon tissue of rats with chronic renal failure. Methods Thirty SPF healthy male SD rats were randomly divided into sham operation group (10 rats) and model group (20 rats). The model group was given adenine 200 mg/(kg·d) by gavage for 4 weeks after left nephrectomy. The general conditions of rats were observed. Serum, renal tissue and colon tissue samples were collected at 4 and 8 weeks after gavage. The levels of serum creatinine, urea nitrogen, TNF-α, IL-6 and LPS were measured by ELISA. Renal and colon tissue were examined by HE staining and microscopy. The protein expressions of LC3, beclin-1, ZO-1 and claudin-1 were detected by Western blot. Results Compared with the sham operation group, the model group rats gradually showed a slow response to external stimuli, slow action, withered and yellow hair color, dull luster, pale conjunctiva and slow weight gain. The levels of serum creatinine, urea nitrogen and inflammatory factors in the model group were all higher than those in the sham operation group, and increased at 8 weeks compared with 4 weeks (P＜0.05). Renal pathology in the model group showed renal tubular dilatation, lymphatic and monocyte infiltration, glomerulosclerosis and interstitial fibrosis. Histopathology of colon in model group showed atrophy and collapse of intestinal villi, infiltration of inflammatory cells in mucosal layer and aggravation of pathological changes, which was more serious at 8 weeks than at 4 weeks. The expression of LC3Ⅱ/Ⅰ, Beclin-1, ZO-1 and Claudin-1 in the model group decreased as compared to those of sham operation group(P＜0.05), and much decreased at 8 weeks as compared with 4 weeks (P＜0.05). Conclusions Autophagy disorder may be a potential mechanism causing intestinal mucosal barrier injury in rats with chronic renal failure.