Metal halide perovskites, such as CsPbX3 (X = Cl, Br, and I), have gained extensive attention due to their increasing demand in optoelectronic applications such as solar cells and lighting-emitting ...devices. Herein, we report a versatile approach to synthesize high-quality CsPbBr3 perovskite nanocrystals (sized 5–15 nm) by ligand-assisted reprecipitation at room temperature. The monodispersed CsPbBr3 nanocube perovskites displayed relatively high photoluminescence quantum yields of 50–80%. By virtue of the quantum size effects, the bandgap energies were manipulated from blue to green spectral regions (410–530 nm). In addition, through compositional modulations of the anion exchange technique, the bright photoluminescence could be almost tuned over the entire visible spectral region (450–650 nm). Furthermore, the photoluminescence of the CsPbBr3 nanocrystals was characterized by narrow emission line widths of 15–50 nm and radiative lifetimes of 5–15 ns. Finally, by taking advantage of these outstanding merits, the CsPbBr3 perovskites were successfully utilized in the application of highly fluorescent patterning and color-purity light-emitting diodes.
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•FeCo-MCM-41 exhibits excellent performance for MO degradation by activating PMS.•FeCo-MCM-41 has good stability and low metal leaching amount.•1O2 plays a dominant role for MO ...degradation in FeCo-MCM-41/PMS system.•The degradation pathways of MO are proposed.
Cobalt-mediated activation of peroxymonosulfate (PMS) has been widely investigated for the effective oxidation of organic contaminants in wastewater. Herein, monometal- and bimetal-doped MCM-41 catalysts (Fe-MCM-41, Co-MCM-41, and FeCo-MCM-41) were synthesized by using one-pot hydrothermal method and attempted to degrade artificial methyl orange (MO) dye wastewater via PMS activation. The influences of initial PMS concentration, pH, catalyst dosage and reaction temperature on the degradation efficiency of MO were systematically examined. Compared with the contrasting catalysts, FeCo-MCM-41 exhibited extremely higher activity and lower amount of metal leaching in the degradation process. The excellent catalytic activity of FeCo-MCM-41 was ascribed to the high dispersion of metals and the synergistic effects of Co2+/Co3+ and Fe2+/Fe3+ redox cycles. A series of radical inhibition and electron paramagnetic resonance experiments revealed that both radical and non-radical pathways were involved in the degradation of MO. Singlet oxygen (1O2) was unveiled to be the dominant reactive oxygen species in the FeCo-MCM-41/PMS system. The possible degradation pathways were proposed based on the identification of intermediate products generated in the degradation process by LC-MS analyses.
Abstract
High expression or aberrant activation of epidermal growth factor receptor (EGFR) is related to tumor progression and therapy resistance across cancer types, including non-small cell lung ...cancer (NSCLC). EGFR tyrosine kinase inhibitors (TKIs) are first-line therapy for NSCLC. However, patients eventually deteriorate after inevitable acquisition of EGFR TKI-resistant mutations, highlighting the need for therapeutics with alternative mechanisms of action. Here, we report that the elevated tribbles pseudokinase 3 (TRIB3) is positively associated with EGFR stability and NSCLC progression. TRIB3 interacts with EGFR and recruits PKCα to induce a Thr654 phosphorylation and WWP1-induced Lys689 ubiquitination in the EGFR juxtamembrane region, which enhances EGFR recycling, stability, downstream activity, and NSCLC stemness. Disturbing the TRIB3-EGFR interaction with a stapled peptide attenuates NSCLC progression by accelerating EGFR degradation and sensitizes NSCLC cells to chemotherapeutic agents. These findings indicate that targeting EGFR degradation is a previously unappreciated therapeutic option in EGFR-related NSCLC.
The recent outbreak of Zika virus (ZIKV) has imposed a serious threat to public health. Here we report the crystal structure of the ZIKV NS5 protein in complex with S-adenosyl-L-homocysteine, in ...which the tandem methyltransferase (MTase) and RNA-dependent RNA polymerase (RdRp) domains stack into one of the two alternative conformations of flavivirus NS5 proteins. The activity of this NS5 protein is verified through a de novo RdRp assay on a subgenomic ZIKV RNA template. Importantly, our structural analysis leads to the identification of a potential drug-binding site of ZIKV NS5, which might facilitate the development of novel antivirals for ZIKV.
Esophageal squamous cell carcinoma (ESCC) is one of the deadliest cancers. We performed exome sequencing on 113 tumor-normal pairs, yielding a mean of 82 non-silent mutations per tumor, and 8 cell ...lines. The mutational profile of ESCC closely resembles those of squamous cell carcinomas of other tissues but differs from that of esophageal adenocarcinoma. Genes involved in cell cycle and apoptosis regulation were mutated in 99% of cases by somatic alterations of TP53 (93%), CCND1 (33%), CDKN2A (20%), NFE2L2 (10%) and RB1 (9%). Histone modifier genes were frequently mutated, including KMT2D (also called MLL2; 19%), KMT2C (MLL3; 6%), KDM6A (7%), EP300 (10%) and CREBBP (6%). EP300 mutations were associated with poor survival. The Hippo and Notch pathways were dysregulated by mutations in FAT1, FAT2, FAT3 or FAT4 (27%) or AJUBA (JUB; 7%) and NOTCH1, NOTCH2 or NOTCH3 (22%) or FBXW7 (5%), respectively. These results define the mutational landscape of ESCC and highlight mutations in epigenetic modulators with prognostic and potentially therapeutic implications.
Microbubble shows great potential for hydrogenation reaction in fixed bed reactors (FBRs). However, the lack of understanding of the hydrodynamic behaviors of microbubble swarm in FBR limits the ...reactor design. In this work, a pilot‐scale HiGee‐aided fixed bed reactor (HFBR), including a HiGee microbubble generator (HMG) and a catalyst bed, has been developed and then applied for poly alpha olefin 4 (PAO 4) hydrogenation. An empirical correlation of Sauter mean diameter (d32) of microbubbles at the inlet and outlet of catalyst bed was established. The gas holdup (φb) of catalyst bed with HMG was 5–10 times higher than that without HMG. Based on d32 and φb, the effective interfacial area in HFBR was calculated as 2000–6000 m2/m3. Compared with static mixer‐aided fixed bed reactor, the aromatic content of PAO 4 hydrogenated in the HFBR was 56%–69% lower, which shows bright future for industrial application.
A chestnut-like aroma is widely considered an important indicator of an excellent-quality green tea; however, the key odorants responsible for chestnut-like aroma have never been systematically ...studied and remain unknown. In this study, the aroma components of green teas and Chinese chestnuts were analyzed using comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-TOFMS), and 58 compounds were identified as common aroma components among green teas, boiled Chinese chestnuts, roasted Chinese chestnuts and raw Chinese chestnuts. Subsequently, 17 volatiles, including 3-methylbutanal, (E)-3-penten-2-one, ethylbenzene, heptanal, benzaldehyde, 2-pentylfuran, octanal, benzeneacetaldehyde, (E)-2-octenal, (E,E)-3,5-octadien-2-one, linalool, nonanal, (E)-2-nonenal, decanal, (Z)-hex-3-en-1-yl hexanoate, trans-β-ionone and (E)-nerolidol, were identified as the key odorants responsible for chestnut-like aroma based on the odor activity value (OAV) calculation method. Besides, the comparison of OAVs of key odorants between fresh tea leaves and finished teas indicated that all key odorants were present in fresh tea leaves and that their contents increased or decreased during tea processing. Moreover, the comparison between results of OAV and gas chromatography-olfactometry (GC-O) methods showed that ethylbenzene, heptanal, benzaldehyde, 2-pentylfuran, (E,E)-3,5-octadien-2-one, linalool, (Z)-hex-3-en-1-yl hexanoate and trans-β-ionone were the common identified compounds between the two methods. The identification of chestnut-like aroma in green teas will provide a theoretical basis for further research on the directional adjustment and control of tea aroma quality.
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•Volatiles of green teas and Chinese chestnuts were analyzed by GC × GC-TOFMS.•58 Compounds were identified as potential key odorants by statistical comparison.•17 Key odorants were determined by OAV calculation and validation analysis.•Key odorants showed different variation trends of contents during processing.•The GC-O analysis of green tea with chestnut-like aroma was performed.
DNA methylation and trimethylated histone H4 Lysine 20 (H4K20me3) constitute two important heterochromatin-enriched marks that frequently cooperate in silencing repetitive elements of the mammalian ...genome. However, it remains elusive how these two chromatin modifications crosstalk. Here, we report that DNA methyltransferase 1 (DNMT1) specifically 'recognizes' H4K20me3 via its first bromo-adjacent-homology domain (DNMT1
). Engagement of DNMT1
-H4K20me3 ensures heterochromatin targeting of DNMT1 and DNA methylation at LINE-1 retrotransposons, and cooperates with the previously reported readout of histone H3 tail modifications (i.e., H3K9me3 and H3 ubiquitylation) by the RFTS domain to allosterically regulate DNMT1's activity. Interplay between RFTS and BAH1 domains of DNMT1 profoundly impacts DNA methylation at both global and focal levels and genomic resistance to radiation-induced damage. Together, our study establishes a direct link between H4K20me3 and DNA methylation, providing a mechanism in which multivalent recognition of repressive histone modifications by DNMT1 ensures appropriate DNA methylation patterning and genomic stability.
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