43 research outputs found

    Interactions of Oxygen and Water Molecules with Pyrite Surface: A New Insight

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    Pyrite is the most common sulfide in nature, and it is well-known for its roles in acid mine drainage, flotation separation of useful metal (Cu, Pb, Zn, and Mo) sulfide minerals, optoelectronic and photovoltaic application, pneumoconiosis, and even in the origin of life. However, the detailed oxidation behaviors of pyrite are still unclear and not well-understood. New oxidation pathways by O<sub>2</sub> on the pyrite (100) surface have been found in this work for the first time using density functional theory simulation; that is, besides Fe sites, S sites are also possible oxidation sites in the initial oxidation state of pyrite, where easier and stronger oxidation may occur. This is the first time to confirm the other researchers’ conjecture on the direct oxidation of S sites, which explains the isotopic composition experiments that a minor amount of O<sub>2</sub> is permanently incorporated into SO<sub>4</sub><sup>2–</sup> during pyrite oxidation (O in SO<sub>4</sub><sup>2–</sup> is mainly derived from water). We constructed various H<sub>2</sub>O–O<sub>2</sub> coadsorption models on the pyrite surface by considering the adsorption sequence of H<sub>2</sub>O and O<sub>2</sub>. It is found that the H<sub>2</sub>O molecule undergoes step-wise dissociation in the presence of the O<sub>2</sub> molecule. Hydroxyl radical •OH is the reactive oxygen species during H<sub>2</sub>O dissociation. Cyclic voltammetric measurements confirm the presence of •OH. In addition, H<sub>2</sub>O<sub>2</sub> may also be formed on the surface in terms of H<sub>2</sub>O-then-O<sub>2</sub> sequence adsorption

    Data_Sheet_1_Acupuncture and moxibustion therapy for cognitive impairment: the microbiome–gut–brain axis and its role.docx

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    Cognitive impairment poses a significant burden on individuals, families, and society worldwide. Despite the lack of effective treatment strategies, emerging evidence suggests that the microbiome–gut–brain (MGB) axis may play a critical role in the pathogenesis of cognitive impairment. While targeted treatment is not yet comprehensive, recently, acupuncture and moxibustion therapy has participated increasingly in the treatment of degenerative diseases and has achieved a certain therapeutic effect. In this review, the possible mechanisms by which acupuncture and moxibustion therapy may improve cognitive impairment through the MGB axis are reviewed, including regulating gut microbial homeostasis, improving intestinal inflammation mediated by the neuroendocrine–immune system, and enhancing intestinal barrier function. We also discuss common acupoints and corresponding mechanism analysis to provide insights into further exploration of mechanisms that target the MGB axis and thereby intervene in cognitive impairment.</p

    Image_1_Bacteria from nodules of Abrus mollis Hance: genetic diversity and screening of highly efficient growth-promoting strains.pdf

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    IntroductionAbrus mollis Hance. (AM) is an important species used in southern Chinese medicine. It is mainly found in Guangdong and Guangxi provinces in China, and it is effective in the treatment of hepatitis. Endophytic bacteria are known to affect the growth and quality of medicinal plants. However, there are limited reports describing endophytic bacteria related to AM.MethodsIn the present study, Illumina-based 16S rRNA gene sequencing was used to investigate the endophytic bacterial communities of root nodules of AM at five sampling sites in Guangxi. In addition, 179 strains of endophytic bacteria were isolated and categorized into 13 haplotypes based on recA sequence analysis.ResultsThe phylogeny of the 16S rRNA gene sequences revealed a predominance of nonrhizobial endophytes. Microbial diversity analysis showed that Proteobacteria was the dominant phylum in all samples, while Bradyrhizobium was the dominant genus in different samples. An efficient strain, Rhizobium tropici FM-19, was screened and obtained through greenhouse experiments. The AM plants inoculated with this strain showed the best growth performance and high nitrogen fixation and nodulation capacity. Notably, total phenols and total flavonoids, important active components in AM, increased by 30.9 and 42.7%, respectively, after inoculation with Rhizobium tropici FM-19.DiscussionThis study provides insights into the complex microbial diversity of AM nodules and provides strain information for the efficient cultivation of AM.</p

    Direct Formation of Electronic Excited NO<sub>2</sub> Contributes to the High Yield of HONO during Photosensitized Renoxification

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    Photosensitized renoxification of HNO3 is found to produce HONO in an unexpectedly high yield, which has been considered an important source for atmospheric HONO. Conventionally, the production of HONO is ascribed to the secondary photolysis of the primarily formed NO2. In this study, by using humic acid (HA) as a model environmental photosensitizer, we provide evidence of the direct formation of NO2 in its electronic excited state (NO2*) as a key intermediate during the photosensitizing renoxification of HNO3. Moreover, the high HONO yield originates from the heterogeneous reaction of the primarily formed NO2* with the co-adsorbed water molecules on HA. Such a mechanism is supported by the increase of the product selectivity of HONO with relative humidity. Further luminescence measurements demonstrate clearly the occurrence of an electronic excited state (NO2*) from photolysis of adsorbed HNO3 on HA. This work deepens our understanding of the formation of atmospheric HONO and gives insight into the transformation of RNS

    Transcriptional regulatory network for transcription factors of MAX and USF1.

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    <p>Diamond represents transcription factor, and circle represents differentially expressed genes (DEGs). Red represents up-regulated expression, and green represents down-regulated expression.</p
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