Contents Graphic: The FE-TEM image of N-doped graphene quantum dots/graphene sheets (N-GQDs/G) and its structural schematic diagram and electrocatalyzing oxygen reduction reaction.
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...•We successfully prepare inexpensive hybrid of N-GQDs/G by simple two-step hydrothermal progresses.•The N-GQDs act as the effective crosslinker and conductive agent for constructing 3D graphene with large specific surface area.•The N-GQDs/G shows high electrocatalytic performance for ORR (dominating four-electron pathway), long-term stability and resistance to methanol crossover.•The pyridinic-N plays an important role for high electrocatalytic activity.
Nitrogen doping carbon nanomaterial has become an important metal-free electrocatalyst for oxygen reduction reaction (ORR) in fue cells. N-doped graphene quantum dots (N-GQDs) are one of the most promising nanomaterials due to abundant electrocatalytic edging and N doping active sites, but low yield, high dispersity and no forming efficient percolative conductive network hinder their direct application as the electrocatalyst. Hydrothermal method is an effective route for preparing high-quality N-GQDs and meanwhile, overcomes the drawbacks of complicated preparing progress and low yield. We further hydrothermally prepare the hybrid material of N-GQDs/Graphene (G) to immobilize N-GQDs on graphene and construct 3D conductive network. Therefore, the inexpensive N-GQDs/G integrates the advantages of rich edges, N doping active sites, high conductivity, and large specific surface area. As confirmed by a series of characterizations and tests, the N-GQDs/G performs high electocatalytic performance (dominating four-electron pathway), long-term stability and resistance to methanol crossover. Moreover, we demonstrate that the type of N specie plays an important role in ORR, especially, the pyridinic-N.
As CO2 emissions are sharply increasing, processes for converting CO2 into value-added products are becoming more desirable. Ruthenium-based catalysts are the most active for CO2 methanation; ...however, their substantially higher cost relative to transition metals makes them prohibitive for industrial application. In this study, we demonstrate porous hexagonal boron nitride (pBN) supports (an ideal support material for thermocatalysts due to the high thermal stability and conductivity) to improve the utilization of Ru and simultaneously enhance the catalytic activity and selectivity for CO2 methanation. A simple vacuum filtration process is proposed that allows the Ru precursor to quickly locate the defects of pBN, where atomic Ru can be restricted onto the defects via B, N coordination through an annealing treatment. The B and N coordinations reduce the valence state of atomic Ru. The as-prepared catalyst with low Ru loading (0.58 wt %) exhibits CH4 selectivity up to 93.5%, catalytic stability after 110 h, and a higher reaction rate 1.86 mmolCO2 /(gcat s) at 350 °C and 1.0 MPa compared to other nanoparticle catalysts. Both atomic-scale size and low valence state of atomic Ru supported on pBN are responsible for the improvement of CH4 production rate as confirmed by density functional theory simulation.
The epithelial‑stromal interaction 1 gene (
) is known to play multiple roles in the malignant progression of breast cancer and also in some aspects of the immune responses to the tumor. However, the ...relevance of the gene in the onset/progression of oral squamous cell carcinoma (OSCC) and lung squamous cell carcinoma (LSCC) is not yet known. The present study was aimed at revealing the roles of
in conferring malignant characteristics to OSCC and LSCC, and the underlying mechanisms. Quantitative real‑time polymerase chain reaction (PCR) and western blot analyses demonstrated significant upregulation of
in all four OSCC cell lines (HSC2, HSC3, HSC3‑M3 and HSC4), and significant downregulation of
in all three LSCC cell lines (LK‑2, EBC‑1 and H226) used in the present study, as compared to the expression levels in the corresponding control cell lines. Both knockdown of
in OSCC and overexpression of the gene in LSCC suppressed cell proliferation, and induced cell‑cycle arrest in the G1 phase, with upregulation of
and downregulation of
and cyclin D1. Furthermore, these alterations of
gene expression in the OSCC and LSCC cell lines suppressed the cell migration ability and reversed the EMT phenotype of the tumor cells. Collectively, while
appears to have oncogenic roles in OSCC, it appears to exert tumor‑suppressive roles in LSCC. PCR array analyses revealed some genes whose expression levels were altered along with the modified
expression in both the OSCC and LSCC cell lines. These findings suggest that
may be a therapeutic target for both OSCC and LSCC.
Acute myeloid leukemia (AML) is one of the most common malignant and aggressive hematologic tumors, and risk stratification is indispensable to ensure proper treatment. But immune-related long ...noncoding RNAs (ir-lncRNAs) pairs prognostic risk models used to stratify AML have yet to be reported. In this study, we established a prognostic risk model based on eight ir-lncRNAs pairs using LASSO-penalized Cox regression analysis and successfully validated the model in an independent cohort. According to risk scores, patients were divided into a high-risk group and a low-risk group. High-risk patients presented more tumor mutation frequency and higher expression of human leukocyte antigen (HLA)-related genes and immune checkpoint molecules. Gene Set Enrichment Analysis (GSEA) indicated that the transforming growth factors β (TGFβ) pathway was activated in the high-risk group; meanwhile, we found that TGFβ1 mRNA levels were significantly elevated in AML patients and correlated with poor prognosis, which is closely related to drug resistance. Consistently, in vitro studies found that exogenous TGFβ1 can protect AML cells from chemotherapy-induced apoptosis. Collectively, we developed an ir-lncRNA prognostic model that helps predict the prognosis of AML patients and provides valuable information about their response to immune checkpoint inhibitors, and we found that increased TGFβ1 levels resulting in chemoresistance may be one of the leading causes of treatment failure in high-risk AML patients.
The secretory proteome plays an important role in the pathogenesis of phytopathogenic fungi. However, the relationship between the large-scale secretome of phytopathogenic fungi and their lifestyle ...is not fully understood. In the present study, the secretomes of 150 plant pathogenic fungi were predicted and the characteristics associated with different lifestyles were investigated. In total, 94,974 secreted proteins (SPs) were predicted from these fungi. The number of the SPs ranged from 64 to 1,662. Among these fungi, hemibiotrophic fungi had the highest number (average of 970) and proportion (7.1%) of SPs. Functional annotation showed that hemibiotrophic and necrotroph fungi, differ from biotrophic and symbiotic fungi, contained much more carbohydrate enzymes, especially polysaccharide lyases and carbohydrate esterases. Furthermore, the core and lifestyle-specific SPs orthogroups were identified. Twenty-seven core orthogroups contained 16% of the total SPs and their motif function annotation was represented by serine carboxypeptidase, carboxylesterase and asparaginase. In contrast, 97 lifestyle-specific orthogroups contained only 1% of the total SPs, with diverse functions such as PAN_AP in hemibiotroph-specific and flavin monooxygenases in necrotroph-specific. Moreover, obligate biotrophic fungi had the largest number of effectors (average of 150), followed by hemibiotrophic fungi (average of 120). Among these effectors, 4,155 had known functional annotation and pectin lyase had the highest proportion in the functionally annotated effectors. In addition, 32 sets of RNA-Seq data on pathogen-host interactions were collected and the expression levels of SPs were higher than that of non-SPs, and the expression level of effector genes was higher in biotrophic and hemibiotrophic fungi than in necrotrophic fungi, while secretase genes were highly expressed in necrotrophic fungi. Finally, the secretory activity of five predicted SPs from
was experimentally verified. In conclusion, our results provide a foundation for the study of pathogen-host interaction and help us to understand the fungal lifestyle adaptation.
Based on the obtained SARs, further structural optimisation of compound BC2021-104511-15i was conducted in this investigation, and totally ten novel quinoline derivates were designed, synthesised and ...optimised for biological activity. Among them, compound 10a displayed significant in vitro anticancer activity against COLO 205 cells with an IC
50
value of 0.11 μM which was over 90-fold more potent than that of Regorafenib (IC
50
>10.0 μM) and Fruquintinib (IC
50
>10.0 μM). Furthermore, compound 10a exhibited over 90-fold selectivity towards COLO 205 relative to human normal colorectal mucosa epithelial cell FHC cells. Flow cytometry study demonstrated that compound 10a could induce apoptosis in COLO 205 cells, however, it could not induce cell cycle arrest in COLO 205 cells. The results of preliminary kinase profile study showed that compound 10a was a potential HGFR and MST1R dual inhibitor, with IC
50
values of 0.11 μM and 0.045 μM, respectively.
Through a simple performance dynamic modulus test (SPT), standard rutting test, Hamburg rutting test, French rutting test and asphalt pavement analyzer rutting test, the rutting resistance of asphalt ...mixtures in the middle and lower courses of three semi-rigid base asphalt pavement of Beijing full-scale test track road in China was evaluated. The test results show that the rutting resistance of asphalt mixtures of the middle and lower courses can be greatly improved by using low-grade asphalt, especially 30# asphalt. The rutting resistance of SBS modified asphalt mixtures is also better. The SPT dynamic modulus test can indirectly characterize the rutting performance of the asphalt mixture. The rutting test results of a laser road detection vehicle and 3 m ruler show that the asphalt grade has a significant impact on the rutting performance of semi-rigid base asphalt pavement. Compared with 70# asphalt used in the middle and lower courses, the rutting resistance of the pavement structure can be improved by more than 20%. The result also show that the APA rutting test results can closely characterize the full-scale test track results, which is an optimal test method for evaluating the rutting performance of semi-rigid base asphalt pavement. The research results can provide a theoretical basis and reference for the rational design and rutting evaluation of semi-rigid base asphalt pavement.
Abstract
The detection and stealth abilities of array antennas depend mainly on the antennas' radiating and scattering performance, respectively. However, the operating environmental loads and ...assembly lead to serious structural errors, including deformation and random errors, which affect both the radiating and scattering performance. As the demand to guarantee high performance in detection as well as in stealth, a new sub‐array level structural compensation method is presented to simultaneously guarantee the radiating and scattering performance of array antennas in service. First, a statistical model of scattering performance with structural deformation and random position error is established to quickly evaluate the impact of a random structural error on scattering performance. Then, the effects of structural errors in different directions on radiating and scattering performance are analysed to determine the structural adjustment direction. Moreover, the multi‐objective problem considering the comprehensive compensation of radiating and scattering performance is converted into a single‐object problem by constructing a fitness function to realise the sub‐array level structural compensation. Finally, a typical case is used to verify the effectiveness of the compensation method. The results show that the presented method can guarantee both the radiating and scattering performance effectively, providing advantageous guidance for structural design and performance compensation for array antennas.
Compared with the traditional heteroatom doping, employing heterostructure is a new modulating approach for carbon‐based electrocatalysts. Herein, a facile ball milling‐assisted route is proposed to ...synthesize porous carbon materials composed of abundant graphene/hexagonal boron nitride (G/h‐BN) heterostructures. Metal Ni powder and nanoscale h‐BN sheets are used as a catalytic substrate/hard template and “nucleation seed” for the formation of the heterostructure, respectively. As‐prepared G/h‐BN heterostructures exhibit enhanced electrocatalytic activity toward H2O2 generation with 86%–95% selectivity at the range of 0.45–0.75 V versus reversible hydrogen electrode (RHE) and a positive onset potential of 0.79 versus RHE (defined at a ring current density of 0.3 mA cm−2) in the alkaline solution. In a flow cell, G/h‐BN heterostructured electrocatalyst has a H2O2 production rate of up to 762 mmol gcatalyst−1 h−1 and Faradaic efficiency of over 75% during 12 h testing, superior to the reported carbon‐based electrocatalysts. The density functional theory simulation suggests that the B atoms at the interface of the G/h‐BN heterostructure are the key active sites. This research provides a new route to activate carbon catalysts toward highly active and selective O2‐to‐H2O2 conversion.
Porous heterostructures of graphene/hexagonal boron nitride are fabricated by a facile ball milling‐assisted route. The porous heterostructure exhibits high electrocatalytic performance toward H2O2 generation (e.g., 86%–95% selectivity). In a flow cell, the production rate is up to 762 mmol gcatalyst−1 h−1, superior to the reported metal‐free catalysts. Density functional theory simulation demonstrates that the B atoms at the G/h‐BN interface are the key active sites.
Large cell neuroendocrine carcinoma (LCNEC) of the lung is a highly aggressive tumor without established standard treatment. The Hedgehog (Hh) signal, which is critical in embryogenesis, is known to ...play important roles in maintaining a malignant phenotype in various cancers. The present study explored the possibility of targeting the Hh signal in the treatment of LCNEC by suppressing Hh downstream molecules, Smoothened (Smo) and GLI family zinc finger 1/2 (Gli1/2), in 3 human LCNEC cell lines. Smo inhibitor, BMS-833923, and Gli inhibitor, GANT61, downregulated Gli1 and 2, resulting in the suppression of the cell viability of the 3 cell lines as assessed using an MTT assay. The downregulation of Gli1 and/or Gli2 using siRNA for each gene also led to cell growth inhibition in the 3 cell lines. The downregulation of Gli1/2 made the cells more sensitive to cisplatin, resulting in increased apoptosis. These findings suggest that the Hh signaling pathway may be a candidate target for the treatment of LCNEC of the lung.
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