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Focusing on innovative high-performance single-pole double-throw nonlinear optical (NLO) molecular switches, two C3v configurations (1 and 3) and one D3h configuration (2) of bipyramidal CaN3Ca have been obtained by using quantum mechanical methods. Not only are 1, 2, and 3 alkaline-earth-based aromatic superalkalis, but they are also interesting electrides. The salt-like electronic structures of e−⋯Ca2+N33−Ca2+ (1) and Ca2+N33−Ca2+⋯e− (3) with localized redox centres are rare inorganic Robin–Day class II-type structures, and e0.5−⋯Ca2+N33−Ca2+⋯e0.5− (2) with a delocalized structure is a class III-type mixed-valent superalkali electride. Under a small external electric field of ±0.0110 a.u. (0.565 V Å−1), the short-distance hopping of Ca atoms in CaN3Ca from the D3h configuration with in-plane aromaticity to each C3v configuration with out-of-plane aromaticity brings about the long-range transfer of half an electron from one Ca atom to another. And, subsequently, a large dipole moment (μ0) and remarkable static first hyperpolarizability (β0) occur. μz and βzzz range from 0 (D3h, off form) to −12.1 or 12.1 D (C3v, on forms) and from 0 (D3h, off form) to −19 428 or 19 428 a.u. (C3v, on forms), respectively. These extremely large differences in μz and βzzz values between the D3h and each of the C3v configurations confirm the potential of these inorganic aromatic Robin–Day-type superalkali electrides for applications in high-sensitivity multi-state nonlinear optical switches. [ABSTRACT FROM AUTHOR]

To explore the active substances exerting anti-tumour effect in lemon essential oil and the molecular mechanism inhibiting the proliferation of head and neck cancer cells SCC15 and CAL33, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay(MTT) was utilized to identify the active component inhibiting the proliferation of head and neck cancer cells, namely citral. The IC_(50) of citral inhibiting the proliferation of head and neck cancer cells and normal cells were also determined. In addition, a 5-ethynyl-2'-deoxyuridine(EdU) staining assay was used to detect the effect of citral on the proliferation rate of head and neck cancer cells, and a colony formation assay was used to detect the effect of citral on tumor sphere formation of head and neck cancer cells in vitro. The cell cycle arrest and apoptosis induction of head and neck cancer cells by citral were evaluated by flow cytometry, and Western blot was used to detect the effect of citral on the expression levels of cell cycle-and apoptosis-related proteins in head and neck cancer cells. The findings indicated that citral could effectively inhibit the proliferation and growth of head and neck cancer cells, with anti-tumor activity, and its half inhibitory concentrations for CAL33 and SCC15 were 54.78 and 25.23 μg·mL~(-1), respectively. Furthermore, citral arrested cell cycle at G_2/M phase by down-regulating cell cycle-related proteins such as S-phase kinase associated protein 2(SKP2), C-MYC, cyclin dependent kinase 1(CDK1), and cyclin B. Moreover, citral increased the cysteinyl aspartate-specific proteinase-3(caspase-3), cysteinyl aspartate-specific proteinase-9(caspase-9), and cleaved poly ADP-ribose polymerase(PARP). It up-regulated the level of autophagy-related proteins including microtubule associated protein 1 light chain 3B(LC3B), sequestosome 1(P62/SQSTM1), autophagy effector protein Beclin1(Beclin1), and lysosome-associate membrane protein 1(LAMP1), suggesting that citral could effectively trigger cell apoptosis and cell autophagy in head and neck cancer cells. Furthermore, the dual-tagged plasmid system mCherry-GFP-LC3 was used, and it was found that citral impeded the fusion of autophagosomes and lysosomes, leading to autophagic flux blockage. Collectively, our findings reveal that the main active anti-proliferation component of lemon essential oil is citral, and this component has a significant inhibitory effect on head and neck cancer cells. Its underlying molecular mechanism is that citral induces apoptosis and autophagy by cell cycle arrest and ultimately inhibits cell proliferation.

The structural and functional characteristics of soil prokaryotic community are important for maintaining ecosystem functions. In this study, we examined the diversity and compositions, the key drivers, as well as functional characteristics of prokaryotic communities in the rhizosphere and non-rhizosphere soils of Picea asperata with different stand ages using high-throughput sequencing technique and bioinformatics methods. The results showed that β -diversity of soil prokaryotic communities in both rhizosphere and non-rhizosphere showed significant differences among different stand ages, but no significant difference between rhizosphere and non-rhizosphere in the same stand age. In terms of community composition at the phylum level, the relative abundances of Proteobacteria and Rokubacteria showed an increasing trend with the increases of stand age, while the relative abundance of Actinobacteria showed a decreasing trend, but no significant difference was observed between 75 year-old planted forests (PF75) and natural forests (NF). The relative abundances of Firmicutes and Thaumarchaeota in the soil of the 25 year-old planted forests (PF25) were significantly higher than in other planted forests and NF. At the genus level, the relative abundances of RB 41, Terrimonas and Acidibacter showed an increasing trend with the increases of stand age, and RB 41 and Terrimonas in rhizosphere soil of PF75 were significantly higher than those in NF . Soil properties and vegetation characteristics jointly influenced the structure of soil prokaryotic communities, with herb layer coverage, soil pH, total phosphorus, and total nitrogen as major drivers. The functional characteristics of soil prokaryotic communities were significantly different among different stand ages. The relative abundances of functions involved in carbon and nitrogen cycle, e.g ., cellulolysis and nitrification, decreased with the increases of stand age, whereas that of sulfate respiration involved in the sulfur cycle increased. We proposed that the structure and functional characteristics of soil prokaryotic communities could serve as important indicators of the development stages of P. asperata forests. In the later stages of plantation forest development, soil nutrient availability could be improved by mediating phosphorus-dissolving and nitrogen-enhancing microorganisms to maintain the stability of the plantation ecosystem.

The diversity and interactions of soil fungal community are the key to maintain the diversity and stability of ecosystem. In this study, we examined the structure, diversity and co-occurrence networks of fungal community in rhizosphere and non-rhizosphere soils of planted and natural Picea asperata forests using high-throughput sequencing technique and bioinformatic methods. The results showed that Inocybaceae and Sebacinaceae were dominant family in soils of planted and natural forests, respectively. At the genus level, Inocybe was dominant one in soils of planted and natural forests. There were significant differences in β -diversity of fungal communities between rhizosphere and non-rhizosphere soils in both planted and natural forests. There were no significant correlations between environmental variables and the relative abundance and α -diversity of fungal communities. Herb layer coverage, soil water content, total organic carbon concentration, and plant species richness played important roles in explaining the variations of β -diversity of fungal communities. Results of the network analysis showed that the negative correlations were dominant among soil fungal communities in natural forest, suggesting that the competition of different groups in natural forest. Moreover, there were more negative correlations in non-rhizosphere soils than in rhizosphere soils, which indicated that fungal communities in non-rhizosphere soils comprised more competitive network structure than in the rhizosphere soils. Biomarker species were identified based on differential abundance analysis. Sebacinaceae was the single shared keystone species in the fungal network which had significant differences among rhizosphere and non-rhizosphere soils of planted and natural forests. Therefore, it is suggested that the variation of differential species in the soil fungal communities between the planted and natural forest might had limited influence on the stability of the community of planted and natural forests.

Focusing on innovative high-performance single-pole double-throw nonlinear optical (NLO) molecular switches, two C3v configurations (1 and 3) and one D3h configuration (2) of bipyramidal CaN3Ca have been obtained by using quantum mechanical methods. Not only are 1, 2, and 3 alkaline-earth-based aromatic superalkalis, but they are also interesting electrides. The salt-like electronic structures of e-Ca2+N33-Ca2+ (1) and Ca2+N33-Ca2+e- (3) with localized redox centres are rare inorganic Robin-Day class II-type structures, and e0.5-Ca2+N33-Ca2+e0.5- (2) with a delocalized structure is a class III-type mixed-valent superalkali electride. Under a small external electric field of ±0.0110 a.u. (0.565 V Å-1), the short-distance hopping of Ca atoms in CaN3Ca from the D3h configuration with in-plane aromaticity to each C3v configuration with out-of-plane aromaticity brings about the long-range transfer of half an electron from one Ca atom to another. And, subsequently, a large dipole moment (μ0) and remarkable static first hyperpolarizability (β0) occur. μz and βzzz range from 0 (D3h, off form) to -12.1 or 12.1 D (C3v, on forms) and from 0 (D3h, off form) to -19 428 or 19 428 a.u. (C3v, on forms), respectively. These extremely large differences in μz and βzzz values between the D3h and each of the C3v configurations confirm the potential of these inorganic aromatic Robin-Day-type superalkali electrides for applications in high-sensitivity multi-state nonlinear optical switches.

The transmission route of TCM knowledge in ancient China primarily included doctor's transmission and non-doctor's transmission. The doctor's transmission mode included lineage-teaching system, elementary study system, transmission between schools and the clinical effects on the society etc. Non-doctor's transmission mode included literati's interests, literati's sickness, literati's health cultivation, the interests of top society, literati's recoding etc. Different transmission modes played an important role in the transmission and conservation of TCM knowledge as well as a reference to developing the transmission of present-day TCM knowledge.