The objective of this study was to study the structure and physicochemical properties of biochar derived from apple tree branches (ATBs), whose valorization is crucial for the sustainable development ...of the apple industry. ATBs were collected from apple orchards located on the Weibei upland of the Loess Plateau and pyrolyzed at 300, 400, 500 and 600 °C (BC300, BC400, BC500 and BC600), respectively. Different analytical techniques were used for the characterization of the different biochars. In particular, proximate and element analyses were performed. Furthermore, the morphological, and textural properties were investigated using scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, Boehm titration and nitrogen manometry. In addition, the thermal stability of biochars was also studied by thermogravimetric analysis. The results indicated that the increasing temperature increased the content of fixed carbon (C), the C content and inorganic minerals (K, P, Fe, Zn, Ca, Mg), while the yield, the content of volatile matter (VM), O and H, cation exchange capacity, and the ratios of O/C and H/C decreased. Comparison between the different samples show that highest pH and ash content were observed in BC500. The number of acidic functional groups decreased as a function of pyrolysis temperature, especially for the carboxylic functional groups. In contrast, a reverse trend was found for the basic functional groups. At a higher temperature, the brunauer–emmett–teller (BET) surface area and pore volume are higher mostly due to the increase of the micropore surface area and micropore volume. In addition, the thermal stability of biochars also increased with the increasing temperature. Hence, pyrolysis temperature has a strong effect on biochar properties, and therefore biochars can be produced by changing pyrolysis temperature in order to better meet their applications.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Pseudocapacitance holds great promise for improving energy densities of electrochemical supercapacitors, but state-of-the-art pseudocapacitive materials show capacitances far below their theoretical ...values and deliver much lower levels of electrical power than carbon-based materials due to poor cation accessibility and/or long-range electron transferability. Here we show that in situ corundum-to-rutile phase transformation in electron-correlated vanadium sesquioxide can yield nonstoichiometric rutile vanadium dioxide layers that are composed of highly sodium ion accessible oxygen-deficiency quasi-hexagonal tunnels sandwiched between conductive rutile slabs. This unique structure serves to boost redox and intercalation kinetics for extraordinary pseudocapacitive energy storage in hierarchical isomeric vanadium oxides, leading to a high specific capacitance of ~1856 F g
(almost sixfold that of the pristine vanadium sesquioxide and dioxide) and a bipolar charge/discharge capability at ultrafast rates in aqueous electrolyte. Symmetric wide voltage window pseudocapacitors of vanadium oxides deliver a power density of ~280 W cm
together with an exceptionally high volumetric energy density of ~110 mWh cm
as well as long-term cycling stability.
Electrochemical reduction of nitrogen to produce ammonia at moderate conditions in aqueous solutions holds great prospect but also faces huge challenges. Considering the high selectivity of Au‐based ...materials to inhibit competitive hydrogen evolution reaction (HER) and high activity of transition metals such as Fe and Mo toward the nitrogen reduction reaction (NRR), it was proposed that Au‐based alloy materials could act as efficient catalysts for N2 fixation based on density functional theory simulations. Only on Mo3Au(111) surface the adsorption of N2 is stronger than H atom. Thermodynamics combined with kinetics studies were performed to investigate the influence of composition and ratio of Au‐based alloys on NRR and HER. The binding energy and reorganization energy affected performance for the initial N2 activation and hydrogenation process. By considering the free‐energy diagram, the computed potential‐determining step was either the first or the fifth hydrogenation step on metal catalysts. The optimum catalytic activity could be achieved by adjusting atomic proportion in alloys to make all intermediate species exhibit moderate adsorption. Free‐energy diagrams of N2 hydrogenation via Langmuir‐Hinshelwood mechanism and hydrogen evolution via Tafel mechanism were compared to reveal that the Mo3Au surface showed satisfactory catalytic performance by simultaneously promoting NRR and suppressing HER. Theoretical simulations demonstrated that Au‐Mo alloy materials could be applied as high‐performance electrocatalysts for NRR.
Electrocatalytic nitrogen reduction reaction: The influences of composition and ratio of Au‐based alloys on the catalytic activity and selectivity of electrochemical nitrogen reduction reaction (NRR) are investigated by theoretical calculations of electronic structures, thermodynamics, and reaction kinetics. Among all the studied bimetallic catalysts, Mo3Au(111) shows the best electrocatalytic performace by promoting NRR and suppressing hydrogen evolution.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Circular RNAs (circRNAs) is one type of important non-coding RNAs that participate in tumorigenesis and cancer progression. In our previous study, we performed a microarray analysis of circRNAs ...between the tumor tissues and the adjacent normal tissues of hepatocellular carcinoma (HCC) patients, and found that the circRNA hsa_circ_0007456 is significantly downregulated in the tumor tissues and correlated with the prognosis of HCC. We further investigated the relationship between the expression levels of hsa_circ_0007456 in HCC and the susceptibility of NK cells, and found that the expression levels of hsa_circ_0007456 in HCC cell lines significantly influenced their susceptibility to NK cells. Through a series of screening and validation, we found that hsa_circ_0007456 mainly functioned through sponging miR-6852-3p and regulating the expression of intercellular adhesion molecule-1 (ICAM-1) in HCC. The miR-6852-3p/ICAM-1 axis is essential for the NK cytotoxicity toward HCC mediated by hsa_circ_0007456. In conclusion, we identify here hsa_circ_0007456 as a promising biomarker of HCC, and highlight hsa_circ_0007456/miR-6852-3p/ICAM-1 axis as an important signaling pathway in the process of tumor immune evasion and the tumorigenesis of HCC.
Dual‐atom catalysts (DAC) are deemed as promising electrocatalysts due to the abundant active sites and adjustable electronic structure, but the fabrication of well‐defined DAC is still full of ...challenges. Herein, bonded Fe dual‐atom catalysts (Fe2DAC) with Fe2N6C8O2 configuration were developed through one‐step carbonization of a preorganized covalent organic framework with bimetallic Fe chelation sites (Fe2COF). The transition from Fe2COF to Fe2DAC involved the dissociation of the nanoparticles and the capture of atoms by carbon defects. Benefitting from the optimized d‐band center and enhanced adsorption of OOH* intermediates, Fe2DAC exhibited outstanding oxygen reduction activity with a half‐wave potential of 0.898 V vs. RHE. This work will guide more fabrication of dual‐atom and even cluster catalysts from preorganized COF in the future.
Fe dual‐atom catalysts with Fe2N6C8O2 configuration were fabricated through the one‐step carbonization of a preorganized covalent organic framework, which exhibited high oxygen reduction activity due to the enhanced adsorption of *OOH, and adjustable d‐band center.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Epigenetic alterations are strongly associated with the development of cancer. The aim of this study was to identify epigenetic pattern in squamous cell lung cancer (LUSC) on a genome-wide scale.
...Here we performed DNA methylation profiling on 24 LUSC and paired non-tumor lung (NTL) tissues by Illumina Human Methylation 450 K BeadArrays, and identified 5214 differentially methylated probes. By integrating DNA methylation and mRNA expression data, 449 aberrantly methylated genes accompanied with altered expression were identified. Ingenuity Pathway analysis highlighted these genes which were closely related to the carcinogenesis of LUSC, such as ERK family, NFKB signaling pathway, Hedgehog signaling pathway, providing new clues for understanding the molecular mechanisms of LUSC pathogenesis. To verify the results of high-throughput screening, we used 56 paired independent tissues for clinical validation by pyrosequencing. Subsequently, another 343 tumor tissues from the Cancer Genome Atlas (TCGA) database were utilized for further validation. Then, we identified a panel of DNA methylation biomarkers (CLDN1, TP63, TBX5, TCF21, ADHFE1 and HNF1B) in LUSC. Furthermore, we performed receiver operating characteristics (ROC) analysis to assess the performance of biomarkers individually, suggesting that they could be suitable as potential diagnostic biomarkers for LUSC. Moreover, hierarchical clustering analysis of the DNA methylation data identified two tumor subgroups, one of which showed increased DNA methylation.
Collectively, these results suggest that DNA methylation plays critical roles in lung tumorigenesis and may potentially be proposed as a diagnostic biomarker.
ChiCTR-RCC-12002830 Date of registration: 2012-12-17.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In plants, reactive oxygen species (ROS) produced following the expression of the respiratory burst oxidase homolog (Rboh) gene are important regulators of stress responses. However, little is known ...about how plants acclimate to salt stress through the Rboh-derived ROS signaling pathway. Here, we showed that a 400-bp fragment of the tobacco (Nicotiana tabacum) NtRbohE promoter played a critical role in the salt response. Using yeast one-hybrid (Y1H) screens, NtbHLH123, a bHLH transcription factor, was identified as an upstream partner of the NtRbohE promoter. These interactions were confirmed by Y1H, electrophoretic mobility assay, and chromatin immunoprecipitation assays. Overexpression of NtbHLH123 resulted in greater resistance to salt stress, while NtbHLH123-silenced plants had reduced resistance to salt stress. We also found that NtbHLH123 positively regulates the expression of NtRbohE and ROS production soon after salt stress treatment. Moreover, knockout of NtRbohE in the 35S::NtbHLH123 background resulted in reduced expression of ROS-scavenging and salt stress-related genes and salt tolerance, suggesting that NtbHLH123-regulated salt tolerance is dependent on the NtbHLH123-NtRbohE signaling pathway. Our data show that NtbHLH123 is a positive regulator and acts as a molecular switch to control a Rboh-dependent mechanism in response to salt stress in plants.
This study aims to identify promising biomarkers for the early detection of lung cancer and evaluate the prognosis of lung cancer patients. Genome-wide mRNA expression data obtained from the Gene ...Expression Omnibus (GSE19188, GSE18842 and GSE40791), including 231 primary tumor samples and 210 normal samples, were used to discover differentially expressed genes (DEGs). NEK2, DLGAP5 and ECT2 were found to be highly expressed in tumor samples. These results were experimentally confirmed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The elevated expression of the three candidate genes was also validated using the Cancer Genome Atlas (TCGA) datasets, which consist of 349 tumor and 58 normal tissues. Furthermore, we performed receiver operating characteristics (ROC) analysis to assess the diagnostic value of these lung cancer biomarkers, and the results suggested that NEK2, DLGAP5 and ECT2 expression levels could robustly distinguish lung cancer patients from normal subjects. Finally, Kaplan-Meier analysis revealed that elevated NEK2, DLGAP5 and ECT2 expression was negatively correlated with both overall survival (OS) and relapse-free survival (RFS). Taken together, these findings indicate that these three genes might be used as promising biomarkers for the early detection of lung cancer, as well as predicting the prognosis of lung cancer patients.
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