Circular RNAs feature prominently in cancer development. Nonetheless, the role of circ_0072088 in hepatocellular carcinoma (HCC) remains unclear. GEO databases (GSE97332, GSE108724, GSE36915, and ...GSE33006) were used to screen out the differentially expressed circRNAs, miRNAs, and mRNA in HCC. The expressions of circ_0072088, miR‐375, and Janus Kinase 2 (JAK2) mRNA in HCC tissue and cell lines were determined with quantitative real‐time polymerase chain reaction. RNase R treatment assay was used to measure the stability of circ_0072088, and subcellular fraction assay was used to detect the localization of circ_0072088. Cell counting kit‐8 assay, flow cytometry, and Transwell assay were used to measure proliferation, apoptosis, migration, and invasion of HCC cells. RNA immunoprecipitation and dual‐luciferase reporter gene assay were employed for investigating the binding sequence between circ_0072088 and miR‐375, as well as miR‐375 and JAK2 3′UTR. Western blot assay was used to detect the expression of JAK2 and p‐STAT3 after circ_0072088 and miR‐375 were selectively regulated. Circ_0072088 and JAK2 mRNA expressions were highly expressed in HCC tissues and cell lines while miR‐375 expression was remarkably downregulated. Circ_0072088 was resistant to RNase R treatment and mainly located in the cytoplasm of HCC cells. The transfection of circ_0072088 overexpression plasmid or miR‐375 inhibitors promoted the proliferation, migration, and invasion, and inhibited the apoptosis of HCC cells, whereas transfection of circ_0072088 siRNA or miR‐375 mimics exerted opposite effects. Besides, miR‐375 was confirmed as a target of circ_0072088 and miR‐375 could further downregulate the expression of JAK2. MiR‐375 mimics could reverse the upregulation of JAK2 and p‐STAT3 protein induced by circ_0072088 overexpression. Circ_0072088 can enhance the proliferation, migration, and invasion, and impede apoptosis of HCC cells. Mechanistically, circ_0072088 activates JAK2/STAT3 signaling pathway by serving as a molecular sponge of miR‐375.
For preventing the excessive consumption of agricultural resources, it is of vital importance to promote agricultural pro-environmental behavior of farmers. Despite the proven importance of ...psychological factors in encouraging farmers’ adoption of organic fertilizer, the evidence is scarce. To fill this gap, this study aims to explore how place attachment and environmental cognition affect farmers’ organic fertilizer adoption with a community sample of 944 rural farmers collected in Hubei province. Specifically, we firstly distinguish two dimensions of place attachment, namely, natural attachment and civic attachment, and then we explore the influence of those dimensions and environmental cognition on farmers’ adoption of organic fertilizer. The results reveal that both place attachment and environmental cognition positively affect farmers’ organic fertilizer adoption. Furthermore, the roles of place attachment vary across different groups divided by farmers’ environmental cognition degree and age. Therefore, to promote green agricultural practices, policy-makers should enhance various farmers’ place attachment and environmental cognition by strengthening infrastructure construction, organizing collective activities, and conducting animation propaganda.
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•The cycles and regeneration of Co(III)/Co(II) and Fe(III)/Fe(II) control reaction kinetics.•The sulfate radical play a crucial role in degrading TC.•The possible degradation ...mechanism of tetracycline is proposed by DFT calculations.•Toxicity of incomplete degradation intermediates is significantly weakened.
High-effective catalyst for activating peroxymonosulfate (PMS) to degrade pollutant in wastewater and minimize its toxicity is crucial. Herein, CoFe2O4/montmorillonite composites (CF/MO) were synthesized and used as high-effective PMS catalysts for the degradation of tetracycline (TC). The CoFe2O4 nanoparticles were firmly loaded on the surface of MO with FeOAl bonds, preventing the leaching of metal ions and bringing superior reusability and stability. It was optimized that the 20%-CF/MO showed superior catalytic activity to activate PMS for TC degradation, and SO4− was the dominant active species for TC complete degradation within 30 min and achieved high kinetic rate of 0.178 min−1. The ultrahigh catalytic performance toward TC degradation was ascribed to the cycles and regeneration of Co(III)/Co(II) and Fe(III)/Fe(II) synthergetic surface redox couples in the catalysts. The TC degradation pathway and reaction mechanism in the 20%-CF/MO/PMS system were also proposed based on DFT calculation. The ecotoxicity of degradation products was assessed using proteomics, and the toxicity of TC was found to decrease significantly as the reaction progressed.
A full set of 8,4′-oxy-8′-phenylneolignans with four chiral carbons, named (+)/(−)-leptolepisols D1‒D2 and (+)/(−)-sophorols A‒F, were isolated from the roots and rhizomes of Sophora tonkinensis ...Gagnep., including 14 previously undescribed stereoisomers, along with 2 known leptolepisol D diastereomers. Their planar structures and relative configurations were elucidated by detailed spectroscopic analysis (HRESIMS and NMR). Based on a highly accurate conformer filtering protocol at low computational cost, the absolute configurations of full set 8,4′-oxy-8′-phenylneolignans were completely assigned by TDDFT calculations of ECD spectra for the first time. Furthermore, (+)/(−)-sophorol A, (−)-sophorol B, and (−)-sophorol E could moderately suppress the lipopolysaccharide-induced nitric oxide production in murine macrophages at 10 μM, with inhibitory ratios of 48.4–52.9%.
A full set of 8,4′-oxy-8′-phenylneolignans with four chiral carbons were isolated from Sophora tonkinensis Gagnep. Four compounds could suppress the LPS-induced NO production in murine macrophages. Display omitted
•Sixteen 8,4′-oxy-8′-phenylneolignans were isolated, 14 of which were undescribed.•The absolute configurations of 8,4′-oxy-8′-phenylneolignans were assigned by TDDFT.•An accurate conformer filtering protocol at low cost for flexible molecules was used.•Four isomers exhibited moderately anti-inflammatory activities.
Bi-geometric transparent composite models (BGTCM) are used to model distributions of transform coefficients in HEVC (High efficiency video coding). Both Kullback-Leibler divergence and χ 2 test show ...that, for both original and quantized transform coefficients in HEVC, BGTCMs provide better modelling performance than popular Laplacian and Cauchy models. Based on BGTCMs, a rate control algorithm is proposed for HEVC. Experimental results using the HEVC reference software show that the proposed algorithm achieves better performance in constant-bit-rate control than previous rate control algorithms based on Laplacian models.
Wuhan,which is hot in summer and cold in winner climatic region,lies in the east of Jianghan Plain.High temperature and high humidity is characteristics of the city.Thus,it's vital to strength the ...natural ventilation of building.Simulation for the situation of wind in Wuhan a certain university in this paper,which take average meteorological element for many years in Wuhan to be initial condition.Selecting Fluent Airpak to conduct flow field Simulation Analysis in the process of calculation.posing problem which exist natural ventilation design universally,according to experimental data,and give tactics to solve it,aiming at utilizing natural wind more effectively and more rationally,and creating comfortable indoor and outdoor thermal environment.
The second extracellular loop (eLP2) of the thromboxane A(2) receptor (TP) had been proposed to be involved in ligand binding. Through two-dimensional (1)H NMR experiments, the overall ...three-dimensional structure of a constrained synthetic peptide mimicking the eLP2 had been determined by our group (Ruan, K.-H., So, S.-P., Wu, J., Li, D., Huang, A., and Kung, J. (2001) Biochemistry 40, 275-280). To further identify the residues involved in ligand binding, a TP receptor antagonist, SQ29,548 was used to interact with the synthetic peptide. High resolution two-dimensional (1)H NMR experiments, NOESY, and TOCSY were performed for the peptide, SQ29,548, and peptide with SQ29,548, respectively. Through completed (1)H NMR assignment and by comparing the different spectra, extra peaks were observed on the NOESY spectrum of the peptide with SQ29,548, which implied the contacts between residues of eLP2 at Val(176), Leu(185), Thr(186), and Leu(187) with SQ29,548 at position H2, H7, and H8. Site-directed mutagenesis was used to confirm the possible ligand-binding sites on native human TP receptor. Each of the four residues was mutated to the residues either in the same group, with different structure or different charged. The mutated receptors were then tested for their ligand binding activity. The receptor with V176L mutant retained binding activity to SQ29,548. All other mutations resulted in decreased or lost binding activity to SQ29,548. These mutagenesis results supported the prediction from NMR experiments in which Val(176), Leu(185), Thr(186), and Leu(187) are the possible residues involved in ligand binding. This information facilitates the understanding of the molecular mechanism of thromboxane A(2) binding to the important receptor and its signal transduction.
Mechanisms of the intramolecular 7(H)→9(H) proton transfer reactions of 2-thioxanthine in the gas phase were investigated with B3LYP/6-311+G(d,p) and G3MP2 methods. Sixteen paths of the proton ...transfers were investigated. The lowest energy barrier, 209.9kJ/mol, is found for the transfer in the imidazole ring via a C8 sp3-type hybrid intermediate. The barriers for the transfers in the pyrimidine ring may be slightly higher, and some of the tautomerizations from 9(H) need quite small energies, predicting that the enol–thiols IM15, IM17, IM19 and IM21, and the keto–thiol IM23 can be observed. Display omitted
► Mechanisms of the intramolecular proton transfers of 2-thioxanthine were proposed. ► Sixteen reaction paths are found within the imidazole and the pyrimidine rings. ► Necessary energy barriers were reported for different products. ► Four enol–thiols species are found to be able to co-exist in the gas phase.
Mechanisms of the intramolecular proton transfer reactions of 2-thioxanthine in the gas phase were investigated with ab initio methods. Geometries of the reactants, transition states, intermediates and products were optimized with B3LYP/6-311+G(d,p). Reaction pathways were confirmed with the intrinsic reaction coordinates. Thermochemistry properties were calculated with the accurate model chemistry method of G3MP2 combined with the standard statistical thermodynamics. Reaction paths were analyzed with respect to the Gibbs free energies. Three paths of the proton transfers in the imidazole ring were discussed in detail, nine necessary energy barriers of the proton transfers in the pyrimidine ring were examined and the tautomerizations between the thiol–enol and keto–thione isomers were investigated. The results show that the highest energy barrier for the imidazole associated paths are 209.9, 306.2 and 224.9kJ/mol, corresponding to a C8 sp3-type hybrid intermediate, a C8 carbene type intermediate and two intermediates of tetrahedral carbons C(4) and C(5). The necessary energy barriers of the pyrimidine ring associated reactions are within 218.3–295.0kJ/mol. The reactions in producing thiol–enol and keto–thiol isomers need smaller energy barriers.
•A framework of intrawell matched stochastic resonance with potential constraint is implemented to release the limitation on nonlinear system response.•The insufficient time-scale matching constraint ...and the inaccurate noise intensity estimation can be eased on potential parameters tuning.•A superior low-noise output performance to the interwell response in the sense of nonlinear filtering effect.•A wider range of frequency response so that can break through the large sampling rate limitation of classical SR.•Better anti-noise capability that expected to perform well in extracting weak line signatures from heavy background noise.
Harmonic signatures extraction is of key interests in remote passive sonar detection and classification for its relevant to the inherent characteristics of engine and shaft/propeller rotations, of which the long-term challenging problem is to address the weak signatures from heavy noise background in the far field scenario. Signal filtering is often utilized as an essential preprocessing tool to purify the acquired noisy signals for applications, whereas stochastic resonance (SR) based nonlinear filter, has been proven effective for weak signature extraction especially under low signal-to-noise ratio (SNR) conditions. In this paper, a novel intrawell matched stochastic resonance (IMSR) is parameterized and implemented to further improve the output signal-to-noise ratio (SNR) with a barrier constrained quartic double-well potential. It can release the limitation on nonlinear system response, and ease the insufficient time-scale matching constraint and the inaccurate noise intensity estimation on potential parameters tuning. The nonlinear filtering effects are comparatively analyzed, which reflect superior performance and can break through the large sampling rate limitation as well. The distinct merits of IMSR are summarized as follows: 1) a superior low-noise output performance to the interwell response in the sense of nonlinear filtering effect; 2) a wider range of frequency response so that can ease the large sampling frequency limitation; 3) better anti-noise capability that expected to perform well in extracting weak line signatures from heavy background noise. Numerical analysis and application verification are performed to confirm the effectiveness and efficiency of the proposed method in comparison with a state-of-the-art second order matched stochastic resonance (SMSR) method, which reflect superior in different contexts.
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