Influence of Organic Sulfur on Low-Temperature Oxidation of Coal and its Transition Characteristics.

The low-temperature oxidation spontaneous combustion of coal was caused by the active groups in its structure. The oxidation mechanism of carbon and oxygen functional groups in coal had been extensively studied, but there were few reports on the study of sulfur functional groups initiating the coal spontaneous combustion. To investigate the influence of organic sulfur functional groups on the spontaneous combustion of high-sulfur coal and explore its transformation characteristics, the low-temperature oxidation experimental system was used to study the spontaneous combustion tendency of coal with similar metamorphic degrees and different organic sulfur contents. The variations of element forms and organic sulfur functional groups were analyzed by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy during low-temperature oxidation of coal and model compounds. The results showed that the forms of organic sulfur in coal mainly included mercaptans, thioethers, thiophenes, sulfones (sulfoxides), and sulfates, and the low-temperature oxidation of coal was not only related to the content of organic sulfur but also related to its type. The coal samples, which possess a low content of total sulfur and a small proportion of active organic sulfur groups such as mercaptans and thioethers, had a lower concentration of indicator gas and a smaller tendency to coal spontaneous combustion. After low-temperature oxidation, the content of mercaptan, thioether, thiophene, methyl(methylene), and pyridine in coal decreased, and the content of oxygen-containing groups such as sulfone (sulfoxide), sulfate, carboxyl, and nitrogen oxide increased. The elements of S, C, and N all changed to a high-valent state. In the oxidation reaction of model compounds, mercaptans were more reactive than thiophenes in the low-temperature region, and the oxidation of thiophene could direct form sulfone (sulfoxide), while the oxidation of mercaptan formed disulfide first. It is speculated that low-valence sulfur migrated to a high-valent state by providing sulfhydryl radicals (•SH) and sulfur radicals (C-S•) combined with active oxygen atoms. After the low-temperature oxidation reaction of model compounds, some organic sulfur existed in the form of aromatic sulfur or sulfur oxides and a small part of sulfur escaped as SO2 and H2S gases in the solid oxidation product.

Difference in Intestinal Flora and Characteristics of Plasma Metabonomics in Pneumoconiosis Patients.

From the two perspectives of intestinal flora and plasma metabolomics, the mechanism of occurrence and development of pneumoconiosis was explored to provide a new target for the prevention and treatment of pneumoconiosis. In this study, 16S ribosome DNA (16SrDNA) gene sequencing technology was used to analyze the differences in intestinal flora of each research group through operational taxonomic units (OUT) analysis, cluster analysis, principal component analysis (PCA), partial least square discriminant analysis (PLS-DA), Kyoto Encyclopedia of Genes and Genomes (KEGG), and other analytical methods were used to analyze the differences in plasma metabolites between the study groups. Metabonomics analysis showed that the plasma metabolites of pneumoconiosis patients were significantly different from those of normal people. Fold change > 2; vip > 1; p < 0.05 were the screening criteria. In the positive and negative mode, we screened ten types of differential metabolites. These ten metabolites were upregulated to varying degrees in the pneumoconiosis patients. Seven metabolic pathways were obtained by analyzing the metabolic pathways of different metabolites. Among them, the aminoacyl tRNA biosynthesis pathway changed most obviously. The α diversity of two groups of intestinal flora was analyzed using the 16SrDNA technique. The results showed that there was no significant difference in ACE, Chao1, Shannon, or Simpson in the two groups (p > 0.05). Beta diversity analysis showed that there were differences in microbial communities. In pneumoconiosis patients, the abundance of Prevotellaceae increased, and the other nine species decreased. Compared to the control group, the abundance of Prevotellaceae in the intestinal flora of pneumoconiosis increased, and the abundance of the other nine species decreased. Compared to controls, ten substances in the plasma metabolites of pneumoconiosis patients were upregulated. Seven metabolic pathways were obtained by analyzing the metabolic pathways of different metabolites. Among them, the aminoacyl tRNA biosynthesis pathway changed most significantly. This provided a theoretical basis for further study on the pathogenesis, early prevention, and treatment of pneumoconiosis.

Metabolic changes of Issatchenkia orientalis under acetic acid stress by transcriptome profile using RNA-sequencing / Cambios metabólicos de Issatchenkia orientalis bajo estrés con ácido acético por perfil de transcriptoma usando secuenciación de ARN

Issatchenkia orientalis (I. orientalis) is tolerant to various environmental stresses especially acetic acid stress in wine making. However, limited literature is available on the transcriptome profile of I. orientalis under acetic acid stress. RNA-sequence was used to investigate the metabolic changes due to underlying I. orientalis 166 (Io 166) tolerant to acetic acid. Transcriptomic analyses showed that genes involved in ergosterol biosynthesis are differentially expressed under acetic acid stress. Genes associated with ribosome function were downregulated, while energy metabolism-related genes were upregulated. Moreover, Hsp70/Hsp90 and related molecular chaperones were upregulated to recognize and degrade misfolded proteins. Compared to Saccharomyces cerevisiae, transcriptomic changes of Io 166 showed many similarities under acetic acid stress. There were significant upregulation of genes in ergosterol biosynthesis and for the application of wine production.(AU)

Molecular dynamics study of Cr doping on the crystal structure and surficial/interfacial properties of 2H-MoS2.

Molecular doping has proved to be an efficient technique to improve the properties of pristine materials. A better understanding of it is quite necessary. For the first time, the force field parameters of the transition metal chromium (Cr) doped in 2H-MoS2 in molecular dynamics (MD) were developed. Compared with the DFT calculation results, the error in the stable-state lattice parameters is less than 1%. The optimized force field parameters were used for the MD simulation of different amounts of Cr substitution doping in 2H-MoS2. This study found that the Cr doping at different sites will have a significant impact on the stability of the bulk 2H-MoS2. With increasing doping amount, the water contact angle increases from 69.2° ± 2° to 78.5° ± 0.4°, and the hydrophobic performance is obviously improved. Finally, we also found that the adsorption energy of Cr-MoS2 decreased with increasing Cr doping content, indicating that bulk MoS2 is easier to separate to form single- or fewer-layer 2H-MoS2 in the case of higher doping content. Comparison between the simulated adsorption energies of typical solvents on the 2H-MoS2 surface shows that methanol (CH3OH) and water (H2O) can separate bulk 2H-MoS2, which matched with the experimental results. By using high-precision force field parameters, molecular dynamics were performed to study the surface/interface characteristics of Cr-doped 2H-MoS2, and provided an effective and detailed description for future experimental design.

Metabolic changes of Issatchenkia orientalis under acetic acid stress by transcriptome profile using RNA-sequencing.

Issatchenkia orientalis (I. orientalis) is tolerant to various environmental stresses especially acetic acid stress in wine making. However, limited literature is available on the transcriptome profile of I. orientalis under acetic acid stress. RNA-sequence was used to investigate the metabolic changes due to underlying I. orientalis 166 (Io 166) tolerant to acetic acid. Transcriptomic analyses showed that genes involved in ergosterol biosynthesis are differentially expressed under acetic acid stress. Genes associated with ribosome function were downregulated, while energy metabolism-related genes were upregulated. Moreover, Hsp70/Hsp90 and related molecular chaperones were upregulated to recognize and degrade misfolded proteins. Compared to Saccharomyces cerevisiae, transcriptomic changes of Io 166 showed many similarities under acetic acid stress. There were significant upregulation of genes in ergosterol biosynthesis and for the application of wine production.

Transcriptome analysis reveals that high temperatures alter modes of lipid metabolism in juvenile turbot (Scophthalmus maximus) liver.

With the increase in farming density and the continuously high summer temperatures against the background of global warming, high temperature stress has become a major challenge in fish farming. In this study, we simulated the high temperature environments (20 °C, 24 °C, and 28 °C) that may occur during turbot culture. High-throughput sequencing was used to investigate the lipid metabolism response patterns in juvenile turbot liver under high temperature stress. A total of 2067 differentially expressed genes (DEGs) were identified. KEGG analysis revealed that the DEGs were mainly associated with glycerophospholipid metabolism, steroid biosynthesis, glycerolipid metabolism, fatty acid metabolic pathways, and the PPAR signaling pathway. A regulatory network was constructed to further elucidate the transcriptional regulation of lipid metabolism. We speculated that high temperature activates PPAR signaling pathway through interaction with ligands such as fatty acids. On the one hand, the HMGCS1 gene in this pathway can inhibit sterol synthesis by down-regulating the expression of key genes in steroid biosynthesis pathway (SQLE, EBP, and DHCR24). On the other hand, the expression of ACSL1 in this pathway is significantly increased under high temperature, which may play an important role in regulating fatty acid metabolism. Moreover, we collected blood and detected changes in serum lipid parameters; the variation patterns were also consistent with our results. These findings reveal that lipid metabolism has an important regulatory role in stress resistance when turbot is exposed to high temperatures.

A rapid liquid chromatography-electrospray ionization-ion mobility spectrometry method for monitoring nine representative metabolites in the seedlings of cucumber and wheat.

A fast and convenient high-performance liquid chromatography-electrospray ionization-ion mobility spectrometry method was developed to determine nine representative metabolites in the seedlings of cucumber and wheat. The analytical conditions were obtained by optimizing the parameters of high-performance liquid chromatography and ion mobility spectrometry. Briefly, acetonitrile-0.1% formic acid solution was selected as the mobile phase for gradient elution at a flow velocity of 0.4 mL/min. Under negative electrospray ionization mode, spray voltage of ion mobility spectrometry was 4.5 kV, and drift tube temperature was set at 90°C. The metabolites from seedling leaves were extracted using 80% acetonitrile as the solvent at 4°C for 12 h. Results showed that under soilless culture conditions, the contents of maltose, citric acid, and p-hydroxybenzoic acid in the seedlings of cucumber and wheat were reduced by low concentration of itaconic acid, succinic acid, and citric acid. Importantly, this analytical approach demonstrated high sensitivity, good linear response, and high selectivity. The lowest limit of detection was 0.004 µg for p-hydroxybenzoic acid. Overall, this high-performance liquid chromatography-electrospray ionization-ion mobility spectrometry method is sensitive and efficient for rapid separation and identification of plant metabolites.

Integrated transcriptomic and proteomic analysis of the acetic acid stress in Issatchenkia orientalis.

Issatchenkia orientalis known as a multi-tolerant non-Saccharomyces yeast, which tolerant environmental stresses, exhibits potential in wine making and bioethanol production. It is essential for the growth of I. orientalis to tolerant acetic acid in the mixed cultures with Saccharomyces cerevisiae. In this work, RNA-sequence and TMT (Tandem Mass Tag) were used to examine the comprehensive transcriptomic and proteomic profiles of I. orientalis in response to acetic acid. The results showed that 876 genes were identified differentially transcribed in I. orientalis genome and 399 proteins expressed in proteome after 4 hr acetic acid (90 mM, pH 4.5). The comprehensive analysis showed a series of determinants of acetic acid tolerance: Glycolysis and TCA cycle provide enough nicotinamide adenine dinucleotide to effectively convert acetic acid. Genes associated with potassium, iron, zinc, and glutathione synthesis were upregulated. The same changes of differentially expressed genes and proteins were mainly concentrated in chaperones, coenzyme, energy production, and transformation. PRACTICAL APPLICATIONS: In addition to the main fermentation products, wine yeast also produces metabolite acetic acid in the fermentation process, and yeast cells are exposed to acetic acid stress, which restrains cell proliferation. Issatchenkia orientalis exhibits great potential in winemaking and bioethanol production. The yeast is known as a multi-tolerant non-Saccharomyces yeast that can tolerate a variety of environmental stresses. In this study, RNA-Seq and TMT were conducted to investigate the changes in transcriptional and proteomic profile of I. orientalis under acetic acid stress. The knowledge of the transcription and expression changes of the I. orientalis is expected to understand the tolerance mechanisms in I. orientalis and to guide traditional fermentation processes by Saccharomyces cerevisiae improving its high resistance to acetic acid stress.

Treatment with Subcritical Water-Hydrolyzed Citrus Pectin Ameliorated Cyclophosphamide-Induced Immunosuppression and Modulated Gut Microbiota Composition in ICR Mice.

Subcritical water can effectively hydrolyze pectin into smaller molecules while still maintaining its functional regions. Pectic heteropolysaccharide can mediate immune regulation; however, the possible effects of subcritical water-hydrolyzed citrus pectin (SCP) on the immune response remain unclear. Therefore, the effects of SCP on immunomodulatory functions and intestinal microbial dysbiosis were investigated using a cyclophosphamide-induced immunosuppressed mouse model. In this research, immunosuppressed ICR mice were administrated with SCP at dosages of 300/600/1200 mg/kg.bw by oral gavage, and body weight, immune organ indexes, cytokines, and gut microbiota were determined. The results showed that subcritical water treatment decreased the molecular mass and increased the content of galacturonic acid in citrus pectin hydrolysates. Meanwhile, the treatment with SCP improved immunoregulatory functional properties and bioactivities over the original citrus pectin. For example, SCP protected immune organs (accelerated recovery of immune organ indexes) and significantly enhanced the expression of immune-related cytokines (IL-2, IL-6, IFN-γ, and TNF-α). The results of the 16S rDNA sequencing analysis on an IlluminaMiSeq platform showed that SCP normalized Cy-induced gut dysbiosis. SCP ameliorated Cy-dependent changes in the relative abundance of several taxa, shifting the balance back to normal status (e.g., SCP increased beneficial Muribaculaceae, Ruminococcaceae, Bacteroidaceae, and Prevotellaceae while decreasing pathogenic Brevundimonas and Streptococcus). The results of this study suggest an innovative application of citrus pectin as an immunomodulator.

Integrated transcriptomic and proteomic analysis of the ethanol stress response in Saccharomyces cerevisiae Sc131.

The molecular mechanism of Saccharomyces cerevisiae tolerant to ethanol stress remains to be further elucidated. In this study, a comprehensive analysis based on RNA-seq and iTRAQ LC-MS/MS was used to investigate the global mechanism of S. cerevisiae strain Sc131 in response to ethanol stress at transcriptomic and proteomic levels. Totally, 937 differentially expressed genes (DEGs) and 457 differentially expressed proteins (DEPs) were identified in Sc131 under ethanol stress. Results revealed that 4-h ethanol stress (10% v/v) can induce filamentous growth, sexual reproduction. Mitochondria and endoplasmic reticulum (ER) were proved to be two important organelles in resisting ethanol stress. Signal transduction such as G-protein coupled receptor signaling and metal ion regulation were remarkably activated at the presence of ethanol. Moreover, silent information regulator (Sir) proteins and aromatic amino acids especially tryptophan were involved in response to ethanol and might be helpful for cell survival. This study provides a global perspective on the mechanism of S. cerevisiae tolerant to ethanol stress and sheds light on the potential application of Sc131 in Chinese bayberry wine brewing. BIOLOGICAL SIGNIFICANCE: It is of great importance for S. cerevisiae to tolerate high levels of ethanol during wine fermentation. However, the molecular mechanism of S. cerevisiae tolerant to ethanol stress remains to be further elucidated at transcriptomic and proteomic levels. In present study, we employed a comprehensive analysis based on RNA-seq and iTRAQ and found several potential pathways involving in the response of Sc131 to ethanol stress. To our knowledge, this is the first integrated analysis combining transcriptomic and proteomic technologies to study the mechanism of Sc131 under ethanol stress.

One-Step Controllable Synthesis of Mesoporous MgCo2 O4 Nanosheet Arrays with Ethanol on Nickel Foam as an Advanced Electrode Material for High-Performance Supercapacitors.

In recent years, ternary transition metal oxides (TTMOs), especially spinel type TTMOs have attracted widespread attention as promising candidates for electrode materials. Among all of the popular TTMOs, MgCo2 O4 is an outstanding one, owing to its superior theoretical capacitance. In this work, MgCo2 O4 nanosheet arrays (NSAs) grown directly on nickel foams were fabricated through a facile hydrothermal process at 120 °C for 4 h. With a series of structural and morphological characterization techniques, it was found that the ethanol played a key role in controlling the composition and morphology during the synthesis process. The MgCo2 O4 NSAs exhibited a superior specific capacitance of 853.06 C g-1 (at 1 mA cm-2 ) and enhanced cycling performance, with 94.65 % of initial capacitance retained after 3000 cycles when used as a binder-free integrated electrode for electrochemical supercapacitors; much higher than other reported data for MgCo2 O4 as well. The excellent electrochemical properties mainly came from the unique morphology of the MgCo2 O4 NSAs. This study will demonstrate the applications of MgCo2 O4 NSAs based large-scale supercapacitors grown on low-cost nickel foams.

Silver Nanoparticle Generators: Silicon Dioxide Microspheres.

A green and simple approach has been developed to synthesize un-coated Ag nanoparticles (AgNPs) in situ on the surface of thiol-group-functionalized silica dioxide microspheres (TSMs) in the aqueous solution. As soon as the Ag+ ions attach onto the surface of TSMs, nucleation and growth of AgNPs can spontaneously complete within one minute without other reducing agents or capping agents. The main reason is that the self-assembled silane-layer formed by mercaptosilane molecules could reduce the Ag0 formation energy, transport electrons efficiently, improve the nucleation density, and protect AgNPs against oxidation. Thus, the supported AgNPs show excellent chemical/photochemical stability in air and solution. Meanwhile, the size of as-prepared AgNPs could be controlled by tuning the concentration of Ag+ ions. This process provides a general route to generate bare AgNPs on the surface of silica dioxide in situ, which might be extended to other materials and is promising in developing novel methodologies for making supported noble metal NPs with desired structure and properties.

Gender differences in visual reflexive attention shifting: evidence from an ERP study.

Attention is considered a central component of cognitive functioning. While many studies have demonstrated that eye direction can trigger reflexive attention shifting, there have been few studies on gender differences in attention shifting. To explore this issue we present results from an event-related potential (ERP) experiment using the spatial cueing task, in which females show larger ERP component amplitude. We suggest this result may be because women have a larger cueing effect in the visual spatial attention task, which leads women to use more attention resources to complete the task. The result may also be because women mature earlier than men in the major brain areas for visual spatial attention, and therefore women have the more mature activation patterns with enhanced amplitude in these regions. Gender differences in visual attention shifting may moderate or contribute to gender differences in other cognitive activities, such as memory, thought, and speech. Future studies of cognitive ability and cognitive processes should pay more attention to the possible effects of gender.