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In recent years, molecular ferroelectrics have received great attention due to their low weight, mechanical flexibility, easy preparation and excellent ferroelectric properties. Among them, crown‐ether‐based molecular ferroelectrics, which are typically composed of the host crown ethers, the guest cations anchored in the crown ethers, and the counterions, are of great interest because of the host‐guest structure. Such a structure allows the components to occur order‐disorder transition easily, which is beneficial for inducing ferroelectric phase transition. Herein, we summarized the research progress of crown ether host‐guest molecular ferroelectrics, focusing on their crystal structure, phase transition, ferroelectric‐related properties. In view of the small spontaneous polarization and uniaxial nature, we outlook the chemical design strategies for obtaining high‐performance crown‐ether‐based molecular ferroelectrics. This minireview will be of guiding significance for the future exploration of crown ether host‐guest molecular ferroelectrics. [ABSTRACT FROM AUTHOR]

To explore the more efficient regulation mechanism of lipid accumulation in Desmodesmus sp. under mixotrophic condition, Desmodesmus sp. were cultivated unde autotrophic and mixotrophic conditions, and differences of lipid accumulation of Desmodesmus sp. under two cultivation conditions were compared using transcriptome sequencing. The results showed that the mixotrophic group had 1081 up-regulated genes, 575 down-regulated genes, and 23 331 non-significantly differentially expressed genes. The enrichment of the differential gene GO term was mainly in the molecular function, biological process and cell components of photosynthesis, such as thylakoid, photosystem I, chlorophyll binding, photosynthetic electron transport, light response and dark response etc. The enrichment of KEGG pathway was mainly characterized as photosynthesis, followed by fatty acid elongation, protein processing in the endoplasmic reticulum, and starch and sucrose synthesis. Under mixotrophic condition, reduced PS II's demand for light energy was reduced, but photosynthetic electron transport was enhanced, and more ATP and NADPH were produced for carbon fixation in photosynthesis and other metabolic activities of cells. The enhancement of lipid accumulation was mainly due to the enhancement of glycolytic pathway, which produced more acetyl- CoA for fatty acid production and promoting fatty acids production. [ABSTRACT FROM AUTHOR]

Questions: What are the characteristics of the spatial patterns of soil seed banks (SSBs) at local scales? How does the spatial distribution of SSBs relate to above‐ground vegetation? Location: The piedmont plain of the eastern slope of Gandur mountain, Wuhai, northwestern China. Methods: A plot of 50 m × 50 m square, divided into 100 quadrats (5 m × 5 m) and 100 subquadrats (1 m × 1 m), was prepared to conduct a field survey of vegetation and SSB sampling. We analyzed the spatial pattern of 196 samples at different scales and directions with geostatistical analysis. The relationship between above‐ground vegetation and SSB was quantified by integrating geostatistics, point pattern analysis, and spatial comparison (IGPS). Results: The SSB density in the study area was 404.5 ± 352 seeds·m−2. SSBs of shrub species and herbaceous species Ⅱ (occurring only below‐ground) had a moderate spatial autocorrelation, and their spatial dependence increased with increasing scale. The SSB of herbaceous species Ⅰ (occurring both above‐ground and below‐ground) had great spatial autocorrelation, and its spatial dependence showed an initial decrease and then increased. Furthermore, SSBs showed lower spatial heterogeneity in the prevailing wind direction than in other directions. The spatial patterns of SSBs of shrub species and herbaceous species Ⅰ correlated with shrubs within a specific range, but not with herbs, while the SSB of herbaceous species Ⅱ did not have a spatial relationship with above‐ground vegetation. Conclusion: The spatial pattern of SSBs had scale dependence features, which exhibited clustered distribution at a certain scale, and were significantly correlated with above‐ground shrubs. Therefore, we suggest subsampling larger quadrats with smaller sample units near shrubs in desert areas. Our workflow seems efficient for determining the spatial pattern of SSBs at medium small scale in arid areas. [ABSTRACT FROM AUTHOR]

Fraction 10 was chromatographed over a column of silica gel with gradient elution by dichloromethane-methanol (50:1-1:1) to yield compounds B 7 b , B 8 b , and B 9 b . Fraction 7 was decolored through an MCI column and then chromatographed over a column of silica gel with gradient elution by dichloromethane-EtOAc (100:1-30:1) to yield compound B 6 b . Fraction 2 was chromatographed over a column of silica gel with gradient elution via dichloromethane-EtOAc (100:1-15:1) to yield compound B 1 b . Fraction 8 was chromatographed over a column of silica gel with gradient elution by petroleum ether-EtOAc (30:1-1:1) and HPLC (acetonitrile-H SB 2 sb O, 7:3) to obtain two compounds B 4 b and B 5 b . [Extracted from the article]

Our exploration of novel inorganic solids with large birefringence in the d10 Metal–Te4+–SO42− system afforded four new sulfate tellurites, Ga2(TeO3)(SO4)(OH)2, In2(TeO3)2(SO4)(H2O), Zn4(Te3O7)2(SO4)2(H2O) and Hg3(Te3O8)(SO4). Notably, Hg3(Te3O8)(SO4) exhibits the largest birefringence at 532 nm (0.184) and 1064 nm (0.166) among the reported metal sulfate tellurites. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of matrine on antigen presentation of dendritic cells (DCs), and to explore the pharmacological mechanism of matrine on anti-tumor effect. Methods: Different concentrations (0, 1, 2, 4, 8 and 16 µ g/mL) of matrine were co-cultured with DCs, the harvested DCs were co-cultured with antigens of Lewis lung cancer (LLC) cells, and then DCs and T cells were co-cultured to produce DCs-activated killer (DAK) cells, which have significant tumor-killing activity. The expression of cytokines, mRNA and protein of toll-like receptors (TLRs) in DCs were detected by enzyme linked immunosobent assay, polymerase chain reaction and Western blot, respectively. And the killing effect of DAK were measured by MTT assay. Results: Matrine significantly increased the mRNA expression of TLR7, TLR8, myeloid differentiation factor 88 (MyD88), tumor necrosis factor receptor-associated factor 6 (TRAF-6) and I κ B kinase (IKK), as well as the protein expression of TLR7 and TLR8, and up-regulated the levels of interleukin-12 (IL-12), IL-6 and tumor necrosis factor-α (TNF-α), meanwhile, it also increased the expressions of MHC-II, CD54, CD80 and CD86 in DCs. DCs-activated effector T cells had significant tumor-killing activity. When the concentration of matrine was more than 4 µg/mL, all indices had significant difference (P<0.01 or P<0.05). Conclusion: Matrine plays an anti-tumor role by regulating TLRs signal transduction pathway, promoting the secretion of inflammatory cytokines and enhancing immune function. [ABSTRACT FROM AUTHOR]