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In this study, common multiwalled and carboxylated carbon nanotubes (CNTs) were added to the cemented lithium tailings backfill (CLTB). The effects of CNTs on the mechanical properties, hydration products, damage process, and microstructure of CLTB specimens were studied by uniaxial compression (UCS), infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). The experimental results show that the addition of CNTs effectively increased the compressive strength compared with the blank control group. When the concentration was 0.05–0.20%, the compressive strength was proportional to the content, the optimal addition amount was 0.2%, and the enhancement effect was 75% and 95.31%, respectively. The FT-IR results indicate that the addition of CNTs increased the total amount of the hydration product but did not affect its type. The hydration of the three-dimensional reciprocal penetration network formed by moderate amounts of CNTs has a positive effect on the mechanical strength of CLTB specimens. [ABSTRACT FROM AUTHOR]

In this study, nPd/Fes were dispersed on peanut shells‐derived alkali‐modified biochar (BCalk) to obtain BCalk‐nPd/Fe composite for overcoming the instability, agglomeration, and oxidation of nPd/Fes. Results demonstrated that the dispersion stability and thermal stability of nPd/Fes were improved and the surface passivation layer was thinned by nanoparticles loading onto the alkalized biochar. Characterization analyses revealed of the improved 2,4‐D dichlorination by BCalk‐nPd/Fe. After biochar alkalization, more Si‐O‐Si sites on BCalk responsible for supporting nZVI particles were formed and coupled with nZVI to generate Si‐O‐Fe. Hence, nPd/Fes were immobilized on BCalk, while the increased oxygen‐containing surface functional groups promoted electron transport between nPd/Fes and 2,4‐D. Therefore, the BCalk‐nPd/Fe exhibited higher dechlorination efficiency toward 2,4‐D than that of nPd/Fe and BCraw‐nPd/Fe. About 99.25% and 89.11% of the 2,4‐D removal and dechlorination, respectively, were achieved after 150 min. Kinetic studies revealed that the removal of 2,4‐D using nPd/Fe, BCraw‐nPd/Fe, and BCalk‐nPd/Fe fitted well in the Langmuir–Hinshelwood kinetic model, and the order of rate constants was as follows: BCalk‐nPd/Fe > BCraw‐nPd/Fe > nPd/Fe. This study suggested that the prepared composites promoted detoxification and harmlessness of 2,4‐D contaminated wastewater and exhibited promising prospect in the efficient treatment of wastewater containing chlorinated organics. [ABSTRACT FROM AUTHOR]

Background: Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder, and its specific pathogenesis is still unclear. We have previously reported that TTX-resistant (TTX-R) sodium channels in colon-specific dorsal root ganglion (DRG) neurons were sensitized in a rat model of visceral hypersensitivity induced by neonatal colonic inflammation (NCI). However, the detailed molecular mechanism for activation of sodium channels remains unknown. This study was designed to examine roles for melatonin (MT) in sensitization of sodium channels in NCI rats. Methods: Colorectal distention (CRD) in adult male rats as a measure of visceral hypersensitivity. Colon-specific dorsal root ganglion (DRG) neurons were labeled with DiI and acutely dissociated for measuring excitability and sodium channel current under whole-cell patch clamp configurations. Western blot and Immunofluorescence were employed to detect changes in expression of Nav1.8 and MT2. Results: The results showed that rats exhibited visceral hypersensitivity after NCI treatment. Intrathecal application of melatonin significantly increased the threshold of CRD in NCI rats with a dose-dependent manner, but has no role in the control group. Whole-cell patch clamp recording showed that melatonin remarkably decreased the excitability and the density of TTX-R sodium channel in DRG neurons from NCI rats. The expression of MT2 receptor at the protein level was markedly lower in NCI rats. 8MP, an agonist of MT2 receptor, enhanced the distention threshold in NCI rats. Application of 8MP reversed the enhanced hypersensitivity of DRG neurons from NCI rats. 8MP also reduced TTX-R sodium current density and modulated dynamics of TTX-R sodium current activation. Conclusions: These data suggest that sensitization of sodium channels of colon DRG neurons in NCI rats is most likely mediated by MT2 receptor, thus identifying a potential target for treatment for chronic visceral pain in patients with IBS. [ABSTRACT FROM AUTHOR]

Abstract Background Irritable bowel syndrome (IBS) is characterized by chronic visceral hyperalgesia (CVH) that manifested with persistent or recurrent abdominal pain and altered bowel movement. However, the pathogenesis of the CVH remains unknown. The aim of this study was to investigate roles of endogenous hydrogen sulfide (H2S) producing enzyme cystathionine beta-synthetase (CBS) and p65 nuclear factor-kappa B subunits in CVH. Results CVH was induced by neonatal maternal deprivation (NMD) in male rats on postnatal days 2–15 and behavioral experiments were conducted at the age of 7–15 weeks. NMD significantly increased expression of CBS in colon-innervating DRGs from the 7th to 12th week. This change in CBS express is well correlated with the time course of enhanced visceromoter responses to colorectal distention (CRD), an indicator of visceral pain. Administration of AOAA, an inhibitor of CBS, produced a dose-dependent antinociceptive effect on NMD rats while it had no effect on age-matched healthy control rats. AOAA also reversed the enhanced neuronal excitability seen in colon-innervating DRGs. Application of NaHS, a donor of H2S, increased excitability of colon-innervating DRG neurons acutely dissociated from healthy control rats. Intrathecal injection of NaHS produced an acute visceral hyperalgesia. In addition, the content of p65 in nucleus was remarkably higher in NMD rats than that in age-matched controls. Intrathecal administration of PDTC, an inhibitor of p65, markedly reduced expression of CBS and attenuated nociceptive responses to CRD. Conclusion The present results suggested that upregulation of CBS expression, which is mediated by activation of p65, contributes to NMD-induced CVH. This pathway might be a potential target for relieving CVH in patients with IBS.

Painful diabetic neuropathy is a common complication of diabetes produced by mechanisms that as yet are incompletely defined. The aim of this study was to investigate the roles of nuclear factor-κB (NF-κB) in the regulation of purinergic receptor P2X ligand-gated ion channel 3 (P2X3R) plasticity in dorsal root ganglion (DRG) neurons of rats with painful diabetes. Here, we showed that hindpaw pain hypersensitivity in streptozocin-induced diabetic rats was attenuated by treatment with purinergic receptor antagonist suramin or A-317491. The expression and function of P2X3Rs was markedly enhanced in hindpaw-innervated DRG neurons in diabetic rats. The CpG (cytosine guanine dinucleotide) island in the p2x3r gene promoter region was significantly demethylated, and the expression of DNA methyltransferase 3b was remarkably downregulated in DRGs in diabetic rats. The binding ability of p65 (an active form of NF-κB) with the p2x3r gene promoter region and p65 expression were enhanced significantly in diabetes. The inhibition of p65 signaling using the NF-κB inhibitor pyrrolidine dithiocarbamate or recombinant lentiviral vectors designated as lentiviral vector-p65 small interfering RNA remarkably suppressed P2X3R activities and attenuated diabetic pain hypersensitivity. Insulin treatment significantly attenuated pain hypersensitivity and suppressed the expression of p65 and P2X3Rs. Our findings suggest that the p2x3r gene promoter DNA demethylation and enhanced interaction with p65 contributes to P2X3R sensitization and diabetic pain hypersensitivity. [ABSTRACT FROM AUTHOR]

La-doped LiVLa(PO) ( x = 0.01, 0.02, and 0.03) cathode materials for lithium ion batteries were synthesized by the microwave-assisted carbothermal reduction method (MW-CTR). The structures and properties of the prepared samples were investigated by X-ray diffraction (XRD) and electrochemical measurements. The results showed that all the three LiVLa(PO) samples had the same monoclinic structures and sharper diffraction peaks of the crystal plane compared with those of the undoped LiV(PO). The initial charge/discharge specific capacity, coulomb efficiency, and discharge decay rate of all the three LiVLa(PO) samples were superior to those of the undoped LiV(PO) sample, and the LiVLa(PO) sample exhibited the best features among the three La-doped LiVLa(PO) samples. Electrochemical impedance spectroscopy (EIS) demonstrated that the LiVLa(PO4) sample had a lower charge transfer resistance and a higher Li ion diffusion coefficient compared with the undoped LiV (PO) sample. [ABSTRACT FROM AUTHOR]