Herein, an electrochemical oxidative cross‐coupling reaction between terminal alkynes and sulfonylhydrazides has been developed. Tetrabutylammonium iodide is used as the electrolyte and redox medium. ...The significant advantages of this method are high atom efficiency, functional group tolerance, and transition metal‐ and oxidant‐free conditions. Most of the compounds exhibit good inhibitory activity on tumor cell lines, and one of the compounds can inhibit cell migration and induce apoptosis in HeLa cells.
A vast amount of text data is recorded in the forms of repair verbatim in railway maintenance sectors. Efficient text mining of such maintenance data plays an important role in detecting anomalies ...and improving fault diagnosis efficiency. However, unstructured verbatim, high-dimensional data, and imbalanced fault class distribution pose challenges for feature selections and fault diagnosis. We propose a bilevel feature extraction-based text mining that integrates features extracted at both syntax and semantic levels with the aim to improve the fault classification performance. We first perform an improved X 2 statistics-based feature selection at the syntax level to overcome the learning difficulty caused by an imbalanced data set. Then, we perform a prior latent Dirichlet allocation-based feature selection at the semantic level to reduce the data set into a low-dimensional topic space. Finally, we fuse fault features derived from both syntax and semantic levels via serial fusion. The proposed method uses fault features at different levels and enhances the precision of fault diagnosis for all fault classes, particularly minority ones. Its performance has been validated by using a railway maintenance data set collected from 2008 to 2014 by a railway corporation. It outperforms traditional approaches.
Industrial waste gas is one of the major sources of atmospheric CO2, yet the direct conversion of the low concentrations of CO2 in waste gases into high value‐added chemicals have been a great ...challenge. Herein, a copper‐based N‐heterocyclic carbene porous polymer catalyst (Cu@NHC‐1) for the direct conversion of low concentration CO2 into oxazolidinones was successfully fabricated via a facile copolymerization process followed by the complexation with Cu(OAc)2. A continuous flow device was designed to deliver a continuous and stable carbon source for the reaction. Due to the triple synergistic effect of its porous structure, nitrogen activation sites and catalytic Cu center, Cu@NHC‐1 shows highly efficient and selective adsorption, activation, and conversion of the low concentration CO2 (30 vol%). Its practical application potential is demonstrated by the ability to successfully convert the CO2 in lime kiln waste gas into oxazolidinones in satisfactory yields under mild conditions.
Fuming value: A copper‐based N‐heterocyclic carbene porous polymer (Cu@NHC‐1) with triple synergistic catalytic effect on the conversion of CO2 via carboxylative cyclization was successfully fabricated to convert CO2 in lime kiln waste gas into value‐added oxazolidinones, providing a prospect for the direct utilization of low concentration CO2 in industrial waste gas.
We introduce confinement effect to overcome disadvantages of directly immobilizing Fe2O3 on the surface of TiO2 by encapsulating Fe2O3 in photocatalyst, which exhibits a higher photocatalytic ...activity.
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•Spatially confined Fe2O3 in hierarchical SiO2@TiO2 (SFT) photocatalyst was prepared.•A complete degradation of antibiotics was achieved under natural sunlight irradiation.•Transformation intermediates and pathways of antibiotics were presented.•This work provided a new insight for constructing other metal oxides confined photocatalysts.
Although TiO2-based photocatalysts have achieved great successes for the degradation of organic pollutants, the complete removal of antibiotics is hard to be realized because of its unique macromolecular ring structure under solar-light irradiation. Herein, this work demonstrates the rational design of the hierarchical hollow SiO2-Fe2O3@TiO2 (SFT) photocatalyst by introducing spatially confined Fe2O3 as a modifier of TiO2, in which inner SiO2 serves as a carrier to support and disperse Fe2O3 in order to obtain small size of Fe2O3 (2–6 nm), while outer TiO2 acts as a bounding wall to protect Fe2O3 from aggregation and abscission. The as-synthesized SFT photocatalyst not only can overcome easy corrosion, dissolution and deactivation of Fe2O3 during the photoreaction process, but also can substantially enhance the adsorption of antibiotics because of its hierarchical hollow structure, facilitating the separation of electron-hole pairs and prolonging the trapping of incident light. Therefore, the SFT photocatalyst manifests the complete removal of antibiotics under simulated solar light irradiation. The intermediates of antibiotics were analyzed by liquid chromatography-mass spectrometry (LC/MS) and the possible degradation pathway was proposed accordingly. Besides, SFT photocatalyst exhibits an excellent recyclability due to confinement effect. Especially, the as-synthesized SFT also achieves the 100% degradation rate of antibiotics under natural sunlight irradiation, efficiently overcoming the incomplete removal of antibiotics for many previous TiO2-based photocatalysts.
With the ever-increasing burden of kidney disease, the need for developing new therapeutics to manage this disease has never been greater. Extracellular vesicles (EVs) are natural membranous ...nanoparticles present in virtually all organisms. Given their excellent delivery capacity in the body, EVs have emerged as a frontier technology for drug delivery and have the potential to usher in a new era of nanomedicine for kidney disease. This review is focused on why EVs are such compelling drug carriers and how to release their fullest potentiality in renal therapeutics. We discuss the unique features of EVs compared to artificial nanoparticles and outline the engineering technologies and steps in developing EV-based therapeutics, with an emphasis on the emerging approaches to target renal cells and prolong kidney retention. We also explore the applications of EVs as natural therapeutics or as drug carriers in the treatment of renal disorders and present our views on the critical challenges in manufacturing EVs as next-generation renal therapeutics.
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•Kidney diseases are global public health concerns lacking effective treatment.•Both native and bioengineered EVs are prime candidates for next-generation renal therapeutics.•EVs can be tailored to target specific renal cells and prolong kidney retention for enhanced efficacy.•EVs can act as natural therapeutic agents or smart drug carriers fighting against renal diseases.
Mining activity for rare earth elements (REEs) has caused serious environmental pollution, particularly for soil ecosystems. However, the effects of REEs on soil microbiota are still poorly ...understood. In this study, soils were collected from abandoned sites of a REEs mine, and the structure, diversity, and co-occurrence patterns of soil microbiota were evaluated by Illumina high-throughput sequencing targeting 16S rRNA genes. Although microbiota developed significantly along with the natural restoration, the microbial structure on the site abandoned for 10 years still significantly differed from that on the unmined site. Potential plant growth promoting bacteria (PGPB) were identified by comparing 16S sequences against a self-constructed PGPB database via BLAST, and it was found that siderophore-producing and phosphorus-solubilizing bacteria were more abundant in the studied soils than in reference soils. Canonical correspondence analysis indicated that species richness of plant community was the prime factor affecting microbial structure, followed by limiting nutrients (total carbon and total nitrogen) and REEs content. Further co-occurring network analysis revealed nonrandom assembly patterns of microbiota in the studied soils. These results increase our understanding of microbial variation and assembly pattern during natural restoration in REE contaminated soils.
Due to their specific properties, ion-adsorption rare earth mine sites may be a threat for adjacent environments. This work was undertaken to assess whether former mining operations on ion-adsorption ...rare earth mine sites have a significant impact on water bodies and soils of the surrounding environments. Tailing soil materials, stream waters and sediments, and farmland soils were collected from one of the largest ion-adsorption rare earth mine sites worldwide (Southern China). Total concentrations of rare earth elements (REEs), Fe, Al, etc., and pH were measured. Results revealed high concentrations of REEs in tailing soils (392 mg kg−1), stream waters (4460 μg L−1), sediments (462 mg kg−1) and farmland soils (928 mg kg−1) in comparison with control sites. In the tailing profiles, light REEs (LREEs) were preferentially leached compared to middle REEs (MREEs) and heavy REEs (HREEs). Anomalies in tailings and stream water indicated strong soil weathering (Eu) and leaching activities (Ce) within the tailings. The MREE enriched pattern in stream water was more related to water parameters such as Al and Fe oxides, and ligands, than to the source of REEs. Anomalies also indicated that REEs contamination in the farmland soils was mainly originated from the stream water contaminated by the leaching from the tailings. In conclusion, a heavy REEs pollution was recorded in the surrounding environment of ion-adsorption rare earth mine. REEs fractionation, Ce and Eu anomalies provided an insight to the understanding of REEs leaching and soil weathering processes, and REEs environmental fate in rare earth mining area.
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•Heavy REEs contamination at ion-adsorption rare earth mine sites, especially stream waters and farmland soils.•Heavy soil weathering and leaching activities within the tailings in which LREEs were preferentially leached.•REEs fractionation and anomalies facilitate to understand REEs geochemistry within ion-adsorption rare earth mine sites.
Summary
Acid mine drainage (AMD) generated by rare earth elements (REEs) deposits exploration contains high concentrations of REEs, ammonium and sulfates, which is quite different from typical ...metallic AMD. Currently, microbial responses and ecological functions in REEs‐AMD impacted rivers are unknown. Here, 16S rRNA analysis and genome‐resolved metagenomics were performed on microbial community collected from a REEs‐AMD contaminated river. The results showed that REEs‐AMD significantly changed river microbial diversity and shaped unique indicator species (e.g. Thaumarchaeota, Methylophilales, Rhodospirillales and Burkholderiales). The main environmental factors regulating community were pH, ammonium and REEs, among which high concentration of REEs increased REEs‐dependent enzyme‐encoding genes (XoxF and ExaF/PedH). Additionally, we reconstructed 566 metagenome‐assembled genomes covering 70.4% of identifying indicators. Genome‐centric analysis revealed that the abundant archaea Thaumarchaeota and Xanthomonadaceae were often involved in nitrification and denitrification, while family Burkholderiaceae were capable of sulfide oxidation coupled with dissimilatory nitrate reduction to ammonium. These indicators play crucial roles in nitrogen and sulfur cycling as well as REEs immobilization in REEs‐AMD contaminated rivers. This study confirmed the potential dual effect of REEs on microbial community at the functional gene level. Our investigation on the ecological roles of indicators further provided new insights for the development of REEs‐AMD bioremediation.
The discovery of hypoxia‐inducible factor (HIF)‐prolyl hydroxylase inhibitor (PHI) has revolutionized the treatment strategy for renal anemia. However, the presence of multiple transcription targets ...of HIF raises safety concerns regarding HIF‐PHI. Here, we explored the dose‐dependent effect of MK‐8617 (MK), a kind of HIF‐PHI, on renal fibrosis. MK was administered by oral gavage to mice for 12 wk at doses of 1.5, 5, and 12.5 mg/kg. In vitro, the human proximal tubule epithelial cell line HK‐2 was treated with increasing doses of MK administration. Transcriptome profiling was performed, and fibrogenesis was evaluated. The dose‐dependent biphasic effects of MK on tubulointerstitial fibrosis (TIF) were observed in chronic kidney disease mice. Accordingly, high‐dose MK treatment could significantly enhance TIF. Using RNA‐sequencing, combined with in vivo and in vitro experiments, we found that Krüppel‐like factor 5 (KLF5) expression level was significantly increased in the proximal tubular cells, which could be transcriptionally regulated by HIF‐1α with high‐dose MK treatment but not low‐dose MK. Furthermore, our study clarified that HIF‐1α‐KLF5‐TGF‐β1 signaling activation is the potential mechanism of high‐dose MK‐induced TIF, as knockdown of KLF5 reduced TIF in vivo. Collectively, our study demonstrates that high‐dose MK treatment initiates TIF by activating HIF‐1α‐KLF5‐TGF‐β1 signaling. These findings provide novel insights into TIF induction by high‐dose MK (HIF‐PHI), suggesting that the safety dosage window needs to be emphasized in future clinical applications.—Li, Z.‐L., Lv, L.‐L., Wang, B., Tang, T.‐T., Feng, Y., Cao, J.‐Y., Jiang, L.‐Q., Sun, Y.‐B., Liu, H., Zhang, X.‐L., Ma, K.‐L., Tang, R.‐N., Liu, B.‐C. The profibrotic effects of MK‐8617 on tubulointerstitial fibrosis mediated by the KLF5 regulating pathway. FASEB J. 33, 12630–12643 (2019). www.fasebj.org
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