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The ZnAl coating was prepared on ring-shaped bonded NdFeB magnets (RSM) via air spraying method with silane as adhesive and flake-like Zn and Al powder as raw materials. The morphology, composition structure and element distribution of the ZnAl coating were characterized by scan electron microscopy with energy-dispersive spectroscopy and x-ray diffraction. The corrosion resistance of the ZnAl coating was analyzed by means of potentiodynamic polarization curve and neutral salt spray test (NSS). The variation in magnetic flux for RSM and ZnAl/RSM was also measured. It was found out that the Zn and Al appeared as metal elements in the coating and superimposed as sheets on the RSM and the ZnAl coating was deposited uniformly and densely with thickness of 16.7 μm. The corrosion current density of ZnAl/RSM was an order of magnitude lower than that of bare RSM and the NSS time attained to 264 h (red rust), indicating the better anticorrosion performance of the ZnAl coating. The magnetic flux of RSM was reduced by 0.15-0.55% after coated with ZnAl, indicating that the coating has little effect on the magnetic property of the RSM.

Iron oxychloride (FeOCl) has been reported to be a highly efficient heterogeneous Fenton catalyst over a wide pH range. In order to determine the true catalytic performance of FeOCl, we simultaneously quantified the adsorptive and oxidative removal of formate, oxalate, and rhodamine-B (RhB) and the formation of RhB oxidation products at both pH 4.0 and 7.0. FeOCl was found to be a poor Fenton catalyst at either pH, as gauged by the oxidation of formate, oxalate, and rhodamine B and the decomposition of H2O2, in comparison with ferrihydrite (Fhy), one of the most common Fe-containing Fenton catalysts. The adsorption of target contaminants to FeOCl and homogeneous Fenton processes, induced by dissolved iron, resulted in overevaluation of the catalytic performance of FeOCl, especially for (i) the use of strongly adsorbing target compounds, without consideration of the role of adsorption in their removal and (ii) exceedingly high concentrations of H2O2 to remove trace quantities of target contaminants. Overall, this study highlights that the systematic quantification of H2O2 decomposition, target compound adsorption, and oxidation as well as the concentrations of oxidized products formed are prerequisites for unequivocal elucidation of the catalytic nature and reaction mechanism of solid Fenton catalysts.

PURPOSE: To acquire the mobile macromolecule (MM) spectrum from healthy participants, and to investigate changes in the signals with age and sex. METHODS: 102 volunteers (49M/53F) between 20 and 69 years were recruited for in vivo data acquisition in the centrum semiovale (CSO) and posterior cingulate cortex (PCC). Spectral data were acquired at 3T using PRESS localization with a voxel size of 30 × 26 × 26 mm(3), pre-inversion (TR/TI 2000/600 ms) and CHESS water suppression. Metabolite-nulled spectra were modeled to eliminate residual metabolite signals, which were then subtracted out to yield a ‘clean’ MM spectrum using the Osprey software. Pearson’s correlation coefficient was calculated between integrals and age for the 14 MM signals. One-way ANOVA was performed to determine differences between age groups. An independent t-test was carried out to determine differences between sexes. RESULTS: MM spectra were successfully acquired in 99 (CSO) and 96 (PCC) of 102 subjects. No significant correlations were seen between age and MM signals. One-way ANOVA also suggested no age-group differences for any MM peak (all p > 0.004). No differences were observed between sex groups. WM and GM voxel fractions showed a significant (p < 0.05) negative linear association with age in the WM-predominant CSO (R = –0.29) and GM-predominant PCC regions (R = –0.57) respectively while CSF increased significantly with age in both regions. CONCLUSION: Our findings suggest that a pre-defined MM basis function can be used for linear combination modeling of metabolite data from different age and sex groups.

PurposeMobile macromolecules (MMs) from amino acids, cytosolic proteins and mobile lipids contribute a significant spectral background underlying the metabolite signals in the MR spectrum. A recent consensus recommends that MM contributions should be removed or included in modeling basis sets for determination of metabolite concentrations and/or metabolite ratios. The purpose of this study was to acquire the MM spectrum from healthy participants at a range of ages, and to investigate changes in the signals with age and sex groups.MethodsInversion time (TI) series were acquired to determine an optimal inversion time to null the metabolite signals. Experiments were carried out using a single adiabatic hyperbolic-secant inversion pulse. After the preliminary experiment, 102 volunteers (49M/53F) between 20 and 69 years were recruited for in vivo data acquisition in the centrum semiovale (CSO) and posterior cingulate cortex (PCC). The protocol consisted of a T1-weighted MPRAGE for structural images, followed by PRESS localization using a voxel size of 30 × 26 × 26 mm3 with pre-inversion (TR/TI 2000/600 ms) and CHESS water suppression. Metabolite-nulled spectra were modeled using a reduced basis set (NAA, Cr, Cho, Glu) and a flexible spline baseline (0.1 ppm knot spacing) followed by subtraction of the modeled metabolite signals to yield a ‘clean’ MM spectrum, using the Osprey software. Pearson’s correlation coefficient was calculated between integrals and age for the 14 MM signals between 0.9–4.2 ppm. One-way ANOVA was performed to determine differences between age groups. An independent t-test was carried out to determine differences between sexes. Relationships between brain tissues with age and sex groups were also measured.ResultsMM spectra were successfully acquired in 99 (CSO) and 96 (PCC) of 102 subjects. No significant correlations were seen between age and MM integrals. One-way ANOVA also suggested no age-group differences for any MM peak (all p > 0.004). No differences were observed between sex groups. The voxels were segmented as 80 ± 4% white matter, 18 ± 4% gray matter, and 2 ± 1% CSF for CSO and 28 ± 4% white matter, 61 ± 4% gray matter and 11 ± 1% CSF for PCC. WM and GM showed a significant (p < 0.05) negative linear association with age in the WM-predominant CSO (R = −0.29) and GM-predominant PCC regions (R = −0.57) respectively while CSF increased significantly with age in both regions.ConclusionOur findings indicate that the MM spectrum is stable across a large age range and between sexes, suggesting a pre-defined MM basis function can be used for linear combination modeling of metabolite data from different age and sex groups.HighlightsA large publicly available MM-aging dataset is presented.Macromolecule signals do not change with age between 20 and 70.There is no sex difference for macromolecule integrals.

Cu(II) enhanced the oxygen activation by Fe(II) to increase the yield of oxidants. However the factors controlling the catalytic performance and indeed the underlying influencing mechanisms remained unclear. Here, we presented the detailed study of Cu(II)-Fe(II) reactions for a range of pH and Cu(II)/Fe(II) ratios. From the results obtained, we provided insight into the factors controlling the redox reactions of Fe-Cu and the catalytic behaviours of active species. A reaction scheme for the Fe(II)/Cu(II) system was developed in which the in-situ formed Cu(I) mainly contributed to producing H2O2 and Fe(II) dominantly decomposed H2O2 to hydroxyl radical (HO ) [see companion article] (Yufan Chen). Circumneutral conditions facilitated the catalytic processes; under acidic conditions, the reverse reaction between Fe(III) and Cu(I) was strongly favoured; alkaline conditions improved the reducing capacity, which subsequently enhanced the generation of Cu(0) instead of Cu(I). There was a saturated Cu(II)/Fe(II) ratio above which further addition of Cu(II) could not be reduced, and then excessive Cu(I) and Cu(II) consumed HO and O2 –, respectively. Therefore, the highest removal efficiency of organic pollutants was achieved when the stoichiometric Cu(II)/Fe(II) ratio was 60% at circumneutral pH. The new findings have implications for the treatment of mixed wastewater where copper and organic pollutants coexist.

The heterogeneous Fenton process has been widely applied though some aspects of this process are still poorly understood. In this study, we simultaneously quantify the adsorption and decomposition of formate and H2O2 at pH 4.0 in the presence of freshly formed ferrihydrite and provide new insights into the ferrihydrite-induced heterogeneous Fenton mechanism with the aid of kinetic and reactive-transport modeling. Our results show that the decomposition of H2O2 and formate is controlled by surface-initiated reactions. Adsorbed formate occupies the surface sites otherwise available for reaction with H2O2 and therefore hampers the surface Fenton reactions despite the negligible accumulation of H2O2 on the surface. The minimal impact of methanol (an effective HO• scavenger) on formate oxidation as well as the poor oxidation of fully adsorbed oxalate compared with the ready oxidation of partially adsorbed formate demonstrates that oxidation mainly occurs in the solid-liquid boundary layer, rather than in bulk or on the surface. This is suggested to be due to the diffusion of surface-generated HO•, rather than surface Fe(II), to the boundary layer with the results of kinetic and reactive-transport modeling supporting this conclusion. The new findings are critical to our understanding of the removal behavior of more complex organic target species and to the design of more effective heterogeneous Fenton technologies.

Purpose Focal cortical dysplasia (FCD) is a major cause of drug-resistant epilepsy; however the underlying epileptogenic mechanisms of FCD metabolism in epilepsy patients remain unclear. The aim of this study is to detect alterations of γ-aminobutyric acid (GABA), glutathione (GSH), and the composite of glutamate and glutamine (Glx) in MRI-typical and neuropathologically confirmed FCD-associated epilepsy using Hadamard Encoding and Reconstruction of Mega-Edited Spectroscopy (HERMES). Materials and methods Fourteen epileptic patients suspected to be caused by FCD and 14 healthy controls were enrolled prospectively in this study; all subjects underwent a 3 T MRI scan, including 3D T1 weighted imaging and HERMES. The GABA signal detected by HERMES also contains signals from macromolecules and homocarnosine, so it is referred as GABA+. Signals of GABA+, GSH and Glx detected by HERMES from tumor foci, contralateral cerebral regions, and healthy controls were quantified using Gannet. Fitting errors and signal to noise ratios (SNRs) of GABA + signals were also recorded. Differences of GABA+, GSH, Glx, fitting error and SNR of GABA + among three groups were analyzed using linear mixed effects models. Results Twelve FCD-associated epilepsy patients (7 females, aged 21.9 ± 9.3 years) and 12 matched healthy controls (7 females, aged 22.8 ± 9.8 years) were finally enrolled in this study. ANOVA results indicated that GABA levels were significantly increased in FCD foci compared with contralateral regions (p = 0.008) and with healthy controls (p = 0.003), while no difference was found in GSH and Glx levels. No difference of fitting errors or SNR of GABA + was found among FCD foci, contralateral regions and healthy controls. Conclusions Increased GABA levels were found in FCD foci that indicated GABA may play a central role in the pathophysiology of FCD patients with epilepsy.

In this study, three GR/Cu(II) (Green Rust/Cu(II)) composites (GRSO4/Cu(II), GRCO3/Cu(II), and GRCl/Cu(II)) were synthesized and used to activate dioxygen under weakly acidic conditions. The change in the mechanism caused by three interlayer anions, CO32−, SO42−, and Cl−, was discussed for the first time. Both Cu(I) and H2O2 were generated during GR/Cu(II)-induced dioxygen activation, resulting in the rapid degradation of acetaminophen. The inconsistency between the reaction constant rates and oxidation reduction potential (ORP) order revealed the effects of the various types of interlayer ions. To further reveal the effects of the anions, the variations in the morphology and valence states of the composites were examined. To identify the rate-controlling step of dioxygen activation by the three composites, the production of reactive oxygen species (ROS) was investigated and compared. The combination of interlayer anions and metal ions changed the oxide morphology of the solid-phase materials. Furthermore, changes in the content of the reductive species (Fe(II) or Cu(I)) either enhanced or inhibited specific reaction steps. The results from this study could deepen our understanding of the effects of anions on dioxygen activation by transition metals and provide a basis for the study of oxidation reactions and mechanisms in the presence of various anions.

Summary Sexual mating of compatible sporida is essential for Sporisorium scitamineum to form dikaryotic mycelia and then cause infection on sugarcane. Our previous work identified a Pseudomonas sp. ST4 from a soil sample, which showed a promising biocontrol potential by inhibiting the mating of S. scitamineum sporida and hyphal growth. In this study, we set to isolate the active compounds from Pseudomonas sp. ST4 through solid fermentation. High‐performance liquid chromatography (HPLC) separation coupling with bioassay showed that Pseudomonas sp. ST4 produced a range of antimicrobial compounds. Two of the major components were purified following acetate extraction, silica gel and HPLC separation. Nuclear magnetic resonance (NMR) and liquid chromatography–mass spectrometry (LC‐MS) analysis identified these active compounds are 4‐hydroxybenzaldehyde and indole‐3‐carbaldehyde respectively. Further analysis showed that the former compound only inhibited the hyphal growth of the fungus at a concentration of 3 mM, while the latter interfered the fungal sexual mating at a concentration of 0.6 mM and affected hyphal growth at a concentration of 2 mM. Treatment of corn plants with 3 mM indole‐3‐carbaldehyde significantly inhibited corn smut infection, with a control rate up to 94%. Further analysis of the structure and activity relationship revealed that indole has a much stronger inhibitory activity against the fungal sexual mating than indole‐3‐carbaldehyde. The results from this study provide new agents for control and prevention of the sugarcane smut disease, and the active compounds could also be used to probe the molecular mechanisms of fungal sexual mating., 4‐hydroxybenzaldehyde and indole‐3‐carbaldehyde from Pseudomonas sp. ST4 were isolated and identified, the former of which inhibited hyphal growth of Sporisorium scitamineum at a concentration of 3 mM, and the latter of which interfered the fungal sexual mating at a concentration of 0.6 mM, and affected hyphal growth at a concentration of 2 mM and has a good control efficacy against sugarcane smut.

This study investigates the effect of H2O on transformation of organic sulphur in coal during CO2 atmospheres by thermodynamic equilibrium calculation by HSC Chemistry. The effect of water vapour on the release of sulphur containing compounds was studied. Detailed S distribution between 200-1400°C was explored. The results show that CO2 not only promotes the formation of inorganic compounds, but also moves the peak of released less complicated organic compounds such as Thiophene, Methylthiophene, Dimethylthiophene, etc. to a much lower temperature. The ranking of the sulphur release in CO2 atmosphere by HSC is: SO2 > Methyl thiophene > Dimethyl thiophene > Ethyl thiophene > dimethyl sulfone. Temperature affects the transformation of sulphur greatly during pyrolysis in CO2 atmosphere. Below 700 °C, COS and H2S are two major sulphur containing compounds formed during pyrolysis in CO2. Above 700 °C, SO2 plays the main role. H2O at different temperature range during heating also reacts with organic sulphur compounds, leading to a further decomposition. Since more organic S stays in inert gas, water promotes the decomposition of organic S compounds more intense than that in CO2 atmosphere. Besides, the effect of water vapour on S distribution depends on the amount of H2O in the reaction.

The influence of a biodegradable agent, N,N-bis(carboxymethyl)glutamic acid (GLDA), on chloramphenicol (CAP) degradation in pyrite/H2O2 system was investigated. The results indicated that the presence of GLDA could extend the working pH range and provided favorable performance at alkaline conditions. The addition of 100 μmol/L GLDA increased the CAP removal rate to 83.3% at pH 8 due to the reinforced formation of OH. The beneficial effect was found to be indifferent of possible reduction of redox potential (Fe(III)/Fe(II)), probable decrease of reaction pH and complex of structured iron on pyrite surface. However, it was correlated well with the facilitated autocatalytic oxidation reaction by Fe(III)-GLDA that promoted cycle of iron, which was confirmed by the determination of ESR and sulfate ion leaching. Based on GC–MS results, the presence of GLDA led to further oxidation of product with reinforced oxidation efficiency, and the potential degradation routine remains similar. All these provide some fundamental insights into the characteristics of environment friendly GLDA-enhanced pyrite/H2O2 system for bio-refractory contaminants removal under neutral or alkaline conditions, and enrich the theoretical knowledge of heterogeneous Fenton-like processes.

Abnormal pattern recognition receptor (PRR) signaling plays an important role in gastric mucosal damage caused by stomach microbiota; however, the underlying molecular mechanisms remain obscure. Here, we show that DC-SIGN, a surface phenotype marker of dendritic cells, is overexpressed in gastric epithelial cells facing LPS stimulation. NLRP3 expression in gastric epithelial cells are significantly increased and related to the degree of LPS stimulation. Furthermore, DC-SIGN could interact with TLR4, promote NLRP3 and related genes expression via MyD88-independent signaling pathway and regulate the secretion of IL-1β and IL-18 in gastric epithelial cells. The results of flow cytometry analysis show that DC-SIGN primarily mediates Th1 differentiation when co-cultured with gastric epithelial cells. These results reveal that LPS-induced DC-SIGN expression modulates NLRP3 inflammasomes formation via MyD88-independent TLR4 signaling in gastric epithelial cell, and induces a Th1-predominant host immune response,these findings may indicate a new function of DC-SIGN in non-immune cells, and elucidate the diversity role of gastric epithelial cells in mechanism of immune damage caused by microbial flora.

In this study, the novel combination of Fe 3+ and FeS 2 /H 2 O 2 system was used to enhance the degradation of chloramphenicol (CAP) by promoting the synergetic effect between the Fe 3+ and the FeS 2 , and the kinetic models to elucidate the reaction mechanisms were validated. Raw pyrite samples were pretreated and characterized by X-ray diffraction, scanning electron microscope, transmission electron microscopy and Brunauer–Emmett–Teller surface area analyzer. Studies on the effects of buffer solution and phosphate on the kinetics of CAP degradation revealed that the autocatalytic effect was associated with the dissolution and generation of Fe 3+ . As confirmed by the experiment to examine the Fe 3+ mediated oxidation of FeS 2 , the catalytic improvement was due to the release of Fe 2+ by the reaction between the FeS 2 and the Fe 3+ at zero-order rate when the Fe 3+ was excessively present. Kinetic models including surface-controlled activation and homogeneous Fenton reactions were responsible for the degradation of CAP.

Glucose-regulated protein 78 (GRP78) is an endoplasmic reticulum stress signaling regulator with anti-apoptotic properties. It has been demonstrated to promote tumor proliferation, survival and metastasis, and to confer resistance against a large variety of therapies. CD24 is a glycosyl-phosphatidylinositol-anchored protein, which is known to have a role in tumor progression, particularly in colorectal cancer (CRC). In the present study, oxaliplatin (L-OHP) was demonstrated to decrease the expression of CD24 in HT29 cells. Knockdown of CD24 using small interfering RNA resulted in sensitization of HT29 cells to L-OHP. By contrast, overexpression of CD24 rendered SW480 cells resistant to L-OHP, which indicated that CD24 antagonized L-OHP-induced cytotoxicity. A co-immunoprecipitation assay revealed that GRP78 physically associates with CD24. L-OHP suppresses the expression of GRP78 and CD24, in part come from the inhibition of interaction between the two. Suppression of GRP78 caused downregulation of CD24 expression and enhanced L-OHP-induced CD24 inhibition. Furthermore, down-regulation of GPR78 with a pharmacological inhibitor sensitized the CRC cells to L-OHP. Collectively, the present results indicate that CD24 antagonizes L-OHP-induced cytotoxicity and that GRP78 is involved in this process. A novel mechanism via which CRC cells acquire resistance to L-OHP was thereby revealed. Use of a combination of compounds which suppress GRP78 may help to improve the effectiveness of L-OHP in the treatment of CRC.

Sugarcane smut is a fungal disease caused by Sporisorium scitamineum, which can cause severe economic losses in sugarcane industry. The infection depends on the mating of bipolar sporida to form a dikaryon and develops into hyphae to penetrate the meristematic tissue of sugarcane. In this study, we set to isolate bacterial strains capable of blocking the fungal mating and evaluate their potential in control of sugarcane smut disease. A bacterial isolate ST4 from rhizosphere displayed potent inhibitory activity against the mating of S. scitamineum bipolar sporida and was selected for further study. Phylogenetic analyses and biochemical characterization showed that the isolate was most similar to Pseudomonas guariconensis. Methanol extracts from minimum and potato dextrose agar (PDA) agar medium, on which strain ST4 has grown, showed strong inhibitory activity on the sexual mating of S. scitamineum sporida, without killing the haploid cells MAT-1 or MAT-2. Further analysis showed that only glucose, but not sucrose, maltose, and fructose, could support strain ST4 to produce antagonistic chemicals. Consistent with the above findings, greenhouse trials showed that addition of 2% glucose to the bacterial inoculum significantly increased the strain ST4 biocontrol efficiency against sugarcane smut disease by 77% than the inoculum without glucose. The results from this study depict a new strategy to screen for biocontrol agents for control and prevention of the sugarcane smut disease.

Dickeya zeae strain EC1 was recently shown to produce a new type of phytotoxins designated as zeamine and zeamine II, which are potent wide-spectrum antibiotics against Gram-positive and Gram-negative bacterial pathogens, suggesting their promising potential as clinical medicines. In this study, the optimized medium composition and culture conditions for biosynthesis of novel antibiotics zeamines have been established by using response surface methodology, largely increasing the yield of zeamines from original about 7.35 µg · mL(-1) in minimal medium to about 150 µg · mL(-1) in LS5 medium. The study identified the major factors contributing to zeamines production, which include nitrate, sucrose, asparaginate, mineral elements Mg2+ and K+, and optimized amount of phosphate. In addition, the results showed that overexpression of zmsK in D. zeae strain EC1 could further increase zeamines yield to about 180 µg · mL(-1) in LS5 medium. The findings from this study could facilitate further characterization and utilization of these two novel antibiotics, and also provide useful clues for understanding the regulatory mechanisms that govern D. zeae virulence.

In order to accelerate the kinetics and improve the utilization of the surface active groups of chitosan (CS) for heavy metal ion removal, sub-micron-sized polystyrene supported chitosan thin-film was synthesized by the electrostatic assembly method. Glutaraldehyde was used as cross-linking agent. Chitosan thin-film was well coated onto the surface of the polystyrene (PS) beads characterized by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX). Their adsorption toward Cu(II) ions was investigated as a function of solution pH, degree of cross-linking, equilibrium Cu(II) ions concentration and contact time. The maximum adsorptive capacity of PS–CS was 99.8 mg/g in the adsorption isotherm study. More attractively, the adsorption equilibrium was achieved in 10 min, which showed superior properties among similar adsorbents. Continuous adsorption–desorption cyclic results demonstrated that Cu(II)-loaded PS–CS can be effectively regenerated by a hydrochloric acid solution (HCl), and the regenerated composite beads could be employed for repeated use without significant capacity loss, indicating the good stability of the adsorbents. The XPS analysis confirmed that the adsorption process was due to surface complexes with atoms of chitosan. Generally, PS beads could be employed as a promising host to fabricate efficient composites that originated from chitosan or other bio-sorbents for environmental remediation.

2,2'-Dihydroxychalcone (2,2'DHC) is a potent inhibitor of glutathione S-transferases (GSTs). Pre-treatment of human colon cancer cells by a non-toxic concentration of this GST inhibitor significantly sensitised cancer cells to chlorambucil and melphalan, which are substrates of glutathione (GSH) conjugation. However, sensitisation to actinomycin D, which has not been shown to be detoxified by GSH-related mechanisms, was not observed. These results further confirm the contribution of GSH-related mechanisms to drug resistance by increased detoxification of drugs. 2,2'DHC inhibited GST activity and the transport of GSH conjugates by cancer cells. Its combined effects on GST and glutathione conjugate export (GS-X) pump may provide more potent sensitisation of cancer cells to chemotherapeutic drugs.