Abstract
The origin of charge density waves (CDWs) in TiSe
$_{2}$$
2
has long been debated, mainly due to the difficulties in identifying the timescales of the excitonic pairing and electron–phonon ...coupling (EPC). Without a time-resolved and microscopic mechanism, one has to assume simultaneous appearance of CDW and periodic lattice distortions (PLD). Here, we accomplish a complete separation of ultrafast exciton and PLD dynamics and unravel their interplay in our real-time time-dependent density functional theory simulations. We find that laser pulses knock off the exciton order and induce a homogeneous bonding–antibonding transition in the initial 20 fs, then the weakened electronic order triggers ionic movements antiparallel to the original PLD. The EPC comes into play after the initial 20 fs, and the two processes mutually amplify each other leading to a complete inversion of CDW ordering. The self-amplified dynamics reproduces the evolution of band structures in agreement with photoemission experiments. Hence we resolve the key processes in the initial dynamics of CDWs that help elucidate the underlying mechanism.
Palladium-catalyzed asymmetric functionalization of unbiased methylene C(sp3)–H bonds is a long-standing challenge. Here, we report a Pd(ii)-catalyzed highly enantioselective arylation of unbiased ...methylene C(sp3)–H bonds enabled by a strongly coordinating bidentate 2-pyridinylisopropyl (PIP) directing group and an easily accessible 3,3′-F2-BINOL chiral ligand. The use of aryl iodides with the combination of 3,3′-F2-BINOL was beneficial for high enantiocontrol. A range of aliphatic amides and aryl iodides were tolerated, providing the desired arylated products in high enantioselectivities (up to 96% ee). The PIP directing group could be removed under mild conditions without erosion of enantiopurity.
The capability of individuals to manage their finances is essential to the outcomes of their entrepreneurial activities. Using panel data from the China Household Finance Survey (C.H.F.S.) in 2013, ...2015 and 2017, this article examines how financial capability affects entrepreneurial performance in rural China. The results demonstrate that financial capability is positively correlated with the scale, profitability and sustainability of entrepreneurship, which is robust in consideration of endogeneity. The effects of financial capability are heterogeneous for different entrepreneurs. Furthermore, technology, labour and land act as the mediating variables through which financial capability improves entrepreneurial performance. Therefore, to facilitate entrepreneurial success, it is important to provide entrepreneurs with financial education. Meanwhile, improvements to the financial environment should also be considered. Additionally, financial institutions should combine financial services with factors, such as technology, land and labour, to improve entrepreneurial performance.
Graphical abstract The mechanisms responsible for AR antagonism of BPA involve inhibiting the AR N/C interaction and enhancing the interactions of AR-SMRT and AR-NCoR. BPA may interfere with the AR ...signaling to exhibit anti-androgenic activity.
A series of novel matrine-dithiocarbamate (DTC) hybrids were efficiently synthesised from matrine through a three-step sequence involving basic hydrolysis, esterification, and DTC formation. They ...were evaluated for their in vitro cytotoxic potency on several human cancer and normal cells. All matrine-DTC hybrids were much more toxic against the human hepatoma cell line HepG2 than the parent matrine. Hybrid 4l (IC50 = 31.39 μM) was the most potent compound against HepG2 cells, being 156- and 3-fold more toxic than matrine (IC50 > 4900 μM) and the reference vincristine (VCR, IC50 = 93.67 μM), respectively. Moreover, hybrid 4l was less toxic to normal human embryonic kidney cell line HEK-293T, with a higher selectivity index (SI, HEK-293T/HepG2 ≈ 6) than matrine (SI ≈ 1) and VCR (SI ≈ 1). The structure-activity relationship analysis indicated that selectivity was greatly boosted when 4-(trifluoromethyl)benzyl was incorporated into the hybrids (4f and 4l). In addition, the hybrid 4l was also highly toxic to the other five types of human cancer cells (Calu-1, SK-BR-3, HUH-7, 786-O and SK-OV-3; IC50 = 44.18–112.19 μM), whereas it was relatively less toxic to the corresponding normal cells (WI-38, LX-2, HEK-293T and KGN; IC50 = 81.48–195.17 μM). Further mechanistic studies showed that hybrid 4l induced apoptosis in a concentration-dependent manner in HepG2 cells. Our results demonstrate that the cytotoxic activity of matrine can be highly enhanced by hybridisation with DTC. Hybrid 4l has promising applications in anticancer drug development.
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•Twelve matrine-dithiocarbamate hybrids were efficiently synthesised from matrine.•All matrine-DTC hybrids were much more toxic to cancer cells HepG2 than matrine.•Hybrid 4l showed 156-fold more toxic than matrine against cancer cells HepG2.•Selectivity was greatly boosted when 4-(trifluoromethyl)benzyl was incorporated.•Apoptosis of HepG2 cells was induced in a concentration-dependent manner by 4l.
Diabetic kidney disease (DKD) is a complication of diabetes, which is the most common cause of end-stage renal disease (dialysis). DKD has a high mortality rate, and only early detection can nip this ...disease in the bud. Advanced glycation end products (AGEs)are generally believed to be involved in the occurrence of DKD. Studies have shown that the lens AGEs fluorescence for noninvasive detection has high consistency with the gold standard OGTT, has high sensitivity and specificity, and could be used as a practical tool for the early screening of type 2 diabetes mellitus (T2DM).Therefore, we speculated that the noninvasive lens AGEs fluorescence detection method can be used to predict the occurrence of DKD. This study detected levels of AGEs in multiple cellular and tissues and analyzed the relationships between AGEs and lens, eyeballs, peripheral blood mononuclear cell (PBMC), serum, and kidney. Additionally, we examined the possible role of lens AGEs fluorescence in DKD screening. Our preexperimental study found that lens AGE levels in patients with T2DM were positively correlated with PBM and serum AGE levels. Lens AGE levels in patients with T2DM were negatively correlated with eGFR and positively correlated with urinary ACR. The animal and cell experiments showed that the AGE levels in the eyeballs of DM mice were also positively correlated with those in the serum and kidney. To increase the reliability of the experiment, we increased the sample size. In our results, lens AGEs levels were positively correlated with the occurrence of DKD, and the incidence of DKD in the high lens AGEs group was 2.739 times that in the low lens AGEs group. The receiver operating characteristic (ROC) curves showed that patients with T2DM with a lens AGEs value ≥ 0.306 were likely to have DKD. The area under the ROC curve of the noninvasive technique for identifying DKD was 0.757 (95% Cl: 0.677-0.838, p<0.001), and the sensitivity and specificity were 70.0% and 78.7%, respectively. These results suggest that noninvasive lens AGEs detection technology has certain clinical value in diagnosing whether patients with T2DM have DKD.
Summary
MicroRNAs are essential in plant development and stress resistance, but their specific roles in drought stress require further investigation.
Here, we have uncovered that a Populus‐specific ...microRNAs (miRNA), miR6445, targeting NAC (NAM, ATAF, and CUC) family genes, is involved in regulating drought tolerance of poplar.
The expression level of miR6445 was significantly upregulated under drought stress; concomitantly, seven targeted NAC genes showed significant downregulation. Silencing the expression of miR6445 by short tandem target mimic technology significantly decreased the drought tolerance in poplar. Furthermore, 5′ RACE experiments confirmed that miR6445 directly targeted NAC029. The overexpression lines of PtrNAC029 (OE‐NAC029) showed increased sensitivity to drought compared with knockout lines (Crispr‐NAC029), consistent with the drought‐sensitive phenotype observed in miR6445‐silenced strains. PtrNAC029 was further verified to directly bind to the promoters of glutathione S‐transferase U23 (GSTU23) and inhibit its expression. Both Crispr‐NAC029 and PtrGSTU23 overexpressing plants showed higher levels of PtrGSTU23 transcript and GST activity while accumulating less reactive oxygen species (ROS). Moreover, poplars overexpressing GSTU23 demonstrated enhanced drought tolerance.
Taken together, our research reveals the crucial role of the miR6445‐NAC029‐GSTU23 module in enhancing poplar drought tolerance by regulating ROS homeostasis. This finding provides new molecular targets for improving the drought resistance of trees.
The asymmetric synthesis of chiral benzo-ring containing compounds through enantioselective intramolecular arylation of unbiased methylene C(sp3)–H bonds was reported. Judicious choice of ...non-C2-symmetric chiral phosphoric acid (CPA) ligand is crucial for the high reactivity and enantioselectivity. The slight decrease in enantioselectivity at the late stage of the reaction was attributed to the hydrolysis of CPA ligands to the corresponding BINOL.
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•Novel rattle-type magnetic hollow molecular imprinted nanospheres were prepared.•A specific ionic liquid was used as the functional monomer.•The nanosphere could be responsive to ...external magnetic field, temperature and pH.
For specific recognition of protein, novel rattle-type magnetic hollow molecular imprinted poly (ionic liquids) nanospheres have been prepared, and bovine serum albumin was selected as the model protein. The rattle-type magnetic Fe3O4@void@PILMIP nanospheres were synthesized by the hard templating method, and characterized by SEM, TEM, FTIR, TGA, and VSM. The as-prepared Fe3O4@void@PILMIP nanospheres could be responsive to external magnetic field, environmental temperature and pH. The results of adsorption isotherm and kinetics showed that the Fe3O4@void@PILMIP nanospheres possessed good recognition and high adsorption capacity of bovine serum albumin. The selective and competitive recognition experiments indicated that the Fe3O4@void@PILMIP nanospheres could selectively recognize bovine serum albumin compared with other proteins (bovine hemoglobin, ovalbumin and lysozyme).
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