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We describe a chiral phosphoric acid (CPA) catalyzed asymmetric [3+3] cycloaddition of N‐viny oxindole nitrones with 2‐indolylmethanols to prepare various spirooxindole[1,2]oxazines in 43–93% yields and 88:12–97:3 enantiomeric ratios. Experimental results revealed that the addition of hexafluoroisopropanol (HFIP) played important roles to help CPA control the reaction reactivity and enantioselectivity. The present method features the construction of a tetrasubstituted chiral carbon stereocenter and the example of N‐vinyl nitrones in asymmetric [3+3] cycloaddition. [ABSTRACT FROM AUTHOR]

The front cover illustrates a chiral phosphoric acid (CPA) catalyzed enantioselective [3+3] cycloaddition of N‐vinyl oxindole nitrones and 2‐indolylmethanols, which was utilized to prepare a variety of spirooxindole[1,2]oxazines. Details can be found in Communication by Wen‐Jun Zhou, and co‐workers (N. Zou, Y.‐Z. Wu, X.‐Y. Zhong, C. Wei, L.‐M. Liao, D.‐L. Mo, W.‐J Zhou, Adv. Synth. Catal. 2024, 366, 4962‐4967; DOI: 10.1002/adsc.202400533)).By Ning Zou; Yu‐Zheng Wu; Xin‐Yi Zhong; Cui Wei; Li‐Min Liao; Dong‐Liang Mo and Wen‐Jun ZhouReported by Author; Author; Author; Author; Author; Author; Author [Extracted from the article]

In this paper, the optimal power allocation problem of two-way relay channel (TWRC) system with analog network coding (ANC) is discussed with asymmetric transmission requirements. The paper provides the closed-form expressions for optimum power allocation in terms of minimum outage probability and maximum sum-rate respectively. It also shows that the two types of optimum power allocation schemes are exactly the same. The analysis indicates that some existing optimal power allocation schemes of TWRC with ANC are special cases of the proposed scheme. Moreover, simulation results show that the achievable outage probability and sum-rate performance of the proposed unified optimum power allocation scheme outperforms that of the uniform power allocation scheme. [ABSTRACT FROM AUTHOR]

Objectives: To analyze the effects of electroacupuncture (EA) at "Fenglong" (ST40) and "Zusanli" (ST36) of different intensities and durations on rats with non-alcoholic fatty liver disease (NAFLD) based on the protein kinase R-like endoplasmic reticulum kinase (PERK)-activating transcription factor 4 (ATF4)-C/EBP homologous protein (CHOP) signaling pathway, so as to explore its mechanism underlying improvement of NAFLD., Methods: SD rats were randomly divided into normal diet group, high-fat model group, sham EA group, strong stimulation EA (SEA) group, and weak stimulation EA (WEA) group, with 15 rats in each group. Each group was further divided into 2, 3, and 4-week subgroups. NAFLD rat model was established by feeding a high-fat diet. After successful modeling, rats in the SEA and WEA groups received EA at bilateral ST40 and ST36 with dense and sparse waves (4 Hz/20 Hz) at current intensities of 4 mA (SEA group) and 2 mA (WEA group), lasting for 20 minutes, once a day, 5 days a week with 2 days of rest. The sham EA group only had the EA apparatus connected without electricity. Different duration subgroups were intervened for 2, 3, and 4 weeks. After the intervention, the contents of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in rats were detected by an automatic biochemical analyzer；liver morphological changes were observed by Oil Red O staining；real-time fluorescence quantitative PCR and Western blot were used to detect the expression of PERK, ATF4, and CHOP mRNAs and proteins in the rat liver tissue., Results: In the high-fat model group, there was a significant accumulation of red lipid droplets in the liver cells, which was reduced significantly in the SEA group at the 4 th week. Compared with the normal diet group with the same treatment duration, the contents of serum ALT, AST, and the expression of PERK, ATF4, and CHOP mRNAs and proteins in the liver tissue were elevated ( P <0.01) in the high-fat model group . Compared with the high-fat model group with the same treatment duration, the contents of serum ALT, AST, and the expression of PERK, ATF4, CHOP mRNAs and proteins in the liver tissue were decreased ( P <0.01, P <0.05) in the SEA and WEA groups. Compared with the sham EA group with the same treatment duration, the contents of serum ALT, AST, and the expression of PERK, ATF4, and CHOP mRNAs were decreased ( P <0.01, P <0.05) in the SEA and WEA groups, the expression of PERK, ATF4, and CHOP proteins in the liver tissue was decreased ( P <0.01) in the SEA group at the 2 nd , 3 rd , and 4 th week, the expression of PERK and CHOP proteins at the 2 nd , 3 rd , 4 th week and ATF4 protein at 2 nd week in the liver tissue were decreased ( P <0.01, P <0.05) in the WEA group. Compared with the SEA group with the same treatment duration, the contents of serum ALT, AST, and the expression of PERK, ATF4, and CHOP mRNAs and proteins in the liver tissue were elevated ( P <0.05, P <0.01) in the WEA group. Compared with the 2-week time point within the groups, the contents of serum ALT, AST, and the expression of PERK, ATF4, and CHOP mRNAs and PERK proteins in the liver tissue were decreased ( P <0.01, P <0.05) in the SEA and WEA groups at 3 rd and 4 th week, the expression of ATF4 proteins in the liver tissue was decreased ( P <0.01) in the SEA group at 3 rd and 4 th week, and the expression of CHOP proteins in the liver tissue was decreased ( P <0.01) in the SEA group at 4 th week and in the WEA group at 3 rd and 4 th week. Compared with the 3-week time point within the groups, the contents of serum ALT, AST, and the expression of PERK, ATF4, and CHOP mRNAs were significantly decreased ( P <0.05, P <0.01) in the SEA and WEA groups at 4 th week, the expression of PERK and CHOP proteins in the liver tissue was decreased ( P <0.01) in the SEA and WEA groups at 4 th week, and the expression of ATF4 protein in the liver tissue was decreased ( P <0.05) in the SEA group at 4 th week., Conclusions: EA at ST40 and ST36 can significantly improve liver function in NAFLD rats, and its mechanism of action may involve inhibiting PERK expression thereby targeting the downstream ATF4/CHOP signaling pathway to suppress endoplasmic reticulum stress, exerting a liver protective effect；the optimal effect was observed with EA intensity of 4 mA for 4 weeks.

To understand the distribution characteristics and restoration status of vegetation at Sanxingdui City Wall, we sampled five typical communities of the city wall at the Sanxingdui site and explored the stability and niche characteristics of herbaceous plant communities under different maintenance measures (natural regeneration, planting, abandoned field, shrub removal, and pruning) following the niche theory and the improved contribution law method. A total of 87 herbaceous species belonging to 73 genera and 31 families were recorded. Compositae and Gramineae were dominant, and perennial herbs were the majority. There were differences in the niche breadth of major herbaceous species under different maintenance measures. The niche breadth of annual plants was higher under natural regeneration and shrub removal, and that of perennial plants was higher under planting, abandoned field, and pruning measures. The niche overlap and similarity of herbaceous plants were higher under natural regene-ration, shrub removal and pruning measures, and were the lowest under planting measure. The importance values were positively correlated with the niche breadth, but the ranking was not completely consistent. Species with higher niche breadth usually had higher probability of niche overlap and higher niche similarity. Combined with the M-Godron's stability analysis, community stability was comparable among shrub removal, pruning, and natural regeneration measures whereas the abandoned field and planting showed lower community stability. We recommended the implementation of in situ conservation measures based on natural regeneration, supplemented by scientific artificial maintenance (shrub removal, pruning, etc .) when necessary, so as to achieve a stable species composition and promote the sustainable development and vegetation landscape restoration at Sanxingdui City Wall.