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As a class of emerging organic contaminants (EOCs), organophosphate flame retardants (OPFRs) have been raising concern due to their persistence, bioaccumulation and toxicity. Therefore, it is urgent need to develop environmental-friendly and high-efficient techniques to remove OPFRs. The degradation kinetics and mechanism of tris-(2-chloroisopropyl) phosphate (TCPP), a representative OPFRs, by UV/TiO2 photocatalytic degradation were explored in current research. It was found that degradation reaction was well documented by first-order kinetics with a kobs of 0.3146 min−1, and hydroxyl radical was identified as a dominating contributor for the TCPP elimination. Simultaneously, six steady intermediate products were generated with the release of Cl− and PO43− as photocatalytic reaction further proceeded. The degradation efficiency can be interfered by natural organic matters, anions and pH value, implying that an incomplete mineralization of TCPP could be ubiquitous in heterogeneous water matrix. Combining the proteomics analysis with KEGG metabolism networks analysis, the process of transmembrane transport and energy generation in Escherichia coli altered by intermediates has proved that the intermediates could be transported and utilized through cellular metabolism. Moreover, the diminution of stress resistance suggested that the toxicity of degradation products through UV/TiO2 photocatalytic degradation was lower than that of intact TCPP. To sum up, environmental safety of degrading intermediate products and the satisfactory detoxification effect of TCPP were identified under appropriate mineralization, indicating that UV/TiO2 photocatalysis technique was safe and high-efficient for TCPP control.

Rice grain with excessive cadmium (Cd) is a major source of dietary Cd intake and a serious threat to health for people who consume rice as a staple food. The development of elite rice cultivars with consistently low Cd content is challenging for conventional breeding approaches, and new strategies urgently need to be developed. Here, we report the development of new indica rice lines with low Cd accumulation and no transgenes by knocking out the metal transporter gene OsNramp5 using CRISPR/Cas9 system. Hydroponic culture showed that Cd concentrations in shoots and roots of osnramp5 mutants were dramatically decreased, resulting in rescue of impaired growth in high Cd condition. Cd-contaminated paddy field trials demonstrated that Cd concentration in osnramp5 grains was consistently less than 0.05 mg/kg, in contrast to high Cd concentrations from 0.33 mg/kg to 2.90 mg/kg in grains of Huazhan (the wild-type indica rice). In particular, the plant yield was not significantly affected in osnramp5 mutants. Furthermore, we developed promising hybrid rice lines with extremely low Cd content in grains. Our work supplies a practical approach to developing Cd pollution-safe indica rice cultivars that minimizes Cd contamination risk in grains.

In this study, we compared the physicochemical properties and starch structures of hybrid rice varieties with similar apparent amylose content but different taste values. In addition to the apparent amylose content, gel permeation chromatography analysis showed that the higher proportions of amylopectin short chains and relatively lower proportions of amylopectin long chains, which could lead to higher peak viscosity and breakdown value, as well as a softer and stickier texture of cooked rice, were the key factors in determining the eating quality of hybrid rice. High-performance anion-exchange chromatography analyses showed that the proportion of amylopectin short chains (degree of polymerization 6-10) and intermediate chains (degree of polymerization 13-24), which might affect the gelatinisation enthalpy and crystallinity, also contributed greatly to the eating quality of hybrid rice. Moreover, this study indicated that a greater diversity of forms and sizes of starch granules might influence the eating quality of hybrid rice.

Using La (NO3)3·6H2O, TiCl4 , and citric acid as the main raw materials, nanocrystalline La2Ti2O7 samples were prepared by microwave assisted method. The structure and morphology of samples were characterized by thermogravimetric and differential thermal analysis (TG-DTA), powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier Transform Infrared (FT-IR) spectroscopy. The photocatalytic activity of La2Ti2O7 was studied for methyl orange (MO) used as simulated sewage. It was found that the single phase La2Ti2O7 could be obtained through the calcination of microwave processed La2Ti2O7 precursors at 600 °C. The resulted product had an approximate spherical shape and average grain size of 50 nm in diameter. Under UV light, the photocatalytic experiment indicated that the prepared La2Ti2O7 nanocrystalline had high photocatalytic activity for degradation of methyl orange.

Using La (NO3)3·6H2O, NH4VO3, citric acid as the main raw materials, nanocrystalline LaVO4 sample was prepared by microwave method. The structure and morphology of sample were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-visible diffuse reflectance spectroscopy (DRS) and Fourier Transform Infrared (FT-IR) spectroscopy. The photocatalytic activity of LaVO4 was studied for methyl orange (MO) used as simulated sewage. The XRD and SEM showed that the particle size of LaVO4 was about 80-100 nm. The DRS showed that LaVO4 had optical absorption onset of 356 nm, indicating the optical band gap of 3.48 eV. The FT-IR showed that LaVO4 had vibration peaks of Fe-O and V-O bond. Under UV-light, the photocatalytic experiment indicated that the prepared LaVO4 nanocrystalline had highly photocatalytic activity for degradation of methyl orange.

Background/Aims: This study investigated signaling pathways via which extracellular histones induce the pro-inflammatory cytokine tumor necrosis factor-α (TNF-α) release from the macrophage cell line RAW 264.7 and the anti-inflammatory efficacy of the antioxidant alpha-lipoic acid (ALA). Methods: ELISA and western blotting analyses were conducted to detect the release of TNF-α from histone-stimulated RAW 264.7 macrophages and the associated phospho-activation of MAPKs (ERK and p38) and NF-κB p65. The effects of ALA on the release of TNF-α and phospho-activation of the MAPKs and NF-κB p65 were studied. P < 0.05 was considered statistically significant. Results: Extracellular histones dose-dependently induced TNF-α release from RAW 264.7 cells and increased the phosphorylation of p38, ERK, and NF-κB p65. TNF-α release was markedly suppressed by p38, ERK, and NF-kB inhibitors. ALA reduced histone-induced TNF-α release, ERK/p38 MAPK activation, and NF-kB activation without affecting macrophage viability. Conclusion: Histones induce TNF-α release from macrophages by activating the MAPK and NF-kB signaling pathways, while ALA suppresses this response by inhibiting ERK, p38 and NF-kB. These findings identify potentially critical inflammatory signaling pathways in sepsis and molecular targets for sepsis treatment.

Triphenyltin (TPT) has severely polluted the environment, and it often coexists with metal ions, such as Cu2+. This paper describesthe cell&rsquo, s molecular recognition of TPT, the interaction betweenTPT recognition and Cu2+ biosorption, and their effecton cell permeability. We studiedthe recognition ofTPT byBacillus thuringiensiscells and theeffect of TPT recognition on Cu2+ biosorption by using atomic force microscopy to observechanges in cell surface mechanical properties and cellular morphology andbyusingflow cytometry to determinethe cell growth status and cell permeability. The results show that B. thuringiensis can quickly recognize different media. The adhesion force of cellsin contact with Tween 80 was significantly reduced to levels that were much lower than that of cells in contact with PBS. Conversely, the cell surface adhesion force increased as TPT became more degraded. B. thuringiensis cells maintained their original morphology after 48 h of TPT treatment. The amount of Cu2+ adsorption by TPT-treated cells was positively correlated with the surface adhesion force (r=0.966, P=0.01). The cell adhesion force significantly decreased after Cu2+adsorption, and cell recognition of TPT and/or Cu2+hindered the entrance of2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) intothe cell. The initial diffusion time of DCFH-DA into cells treated by PBS, Cu2+, TPT, and TPT+Cu2+was4, 10, 30, and 30 min, respectively, andthe order of the fluorescence intensity wasPBS &gt, &gt, Cu2+&gt, TPT &gt, TPT+Cu2+. We conclude that changes in the cell surface properties of the microbe during recognition of pollutants depend on the contaminant&rsquo, s properties. B. thuringiensis recognized TPT and secreted intracellular substancesthatnot only enhanced the adsorption of Cu2+, but also formed a &ldquo, barrier&rdquo, on the cell surface that reduced permeability. These findings provide a novel insight into the mechanism of microbial removal of pollutants.

Microbiologic experiments together with Tessier sequential extraction and ICP-OES determination showed that distributions of Pb, Cu, Cd and Cr in soil of Guiyu, an e-waste dismantling region in South China, have changed after activities of native combined Bacillus cereus. Exchangeable fractions of these heavy metals were 1.52, 12.32, 3.98 and 34.50-fold those of original ones after 8 h interaction, here the organic phases were supposed to be the main alteration origin. The changing interaction time brought different impacts on concentration variation of heavy metals. Decabromodiphenyl ether (BDE209) influenced combined Bacillus cereus to redistribute the shares of heavy metals. BDE209 of 1 mg/L favored the alteration to make heavy metals become more bioavailable, while 5 mg/L and 10 mg/L of BDE209 baffled this alteration. However, influences of these strains on heavy metal speciation could be generally enhanced at the presence of BDE209, particularly for Cu and Pb Therefore, non-residual fractions were easier to be transferred into bioavailable ones after interaction with biomass, thus favoring the subsequent bioremediation of soil.

A series of Fe–Ce–Ti catalysts were prepared via co-precipitation method to investigate the effect of doping Ce into Fe–Ti catalysts for selective catalytic reduction of NO with NH3. The NO conversion over Fe–Ce–Ti catalysts was considerably improved after Ce doping compared to that of Fe–Ti catalysts. The Fe(0.2)–Ce(0.4)–Ti catalysts exhibited superior catalytic activity to that of Fe(0.2)–Ti catalysts. The obtained catalysts were characterized by N2 adsorption (BET), X-ray diffraction (XRD), temperature programmed reduction (H2-TPR), temperature programmed desorption (NH3-TPD), Fourier transform infrared (FT-IR) spectrophotometry, thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS). The data showed that the introduction of Ce results in higher surface area and better dispersion of active components on the catalyst surface and enhances the amount of surface acid sites. The interactions between Fe and Ce species were found to improve the redox ability of the catalyst, which promotes catalytic performance at low temperature. The XPS results revealed that Fe3+/Fe2+ and Ce4+/Ce3+ coexisted on the catalyst surface and that Ti was in 4+ oxidation state on catalyst surface. Ce doping increased the atomic ratio of Fe/Ti and Ce/Ti and enhanced the surface adsorbed oxygen species. In addition, Fe(0.2)–Ce(0.4)–Ti catalyst also showed better tolerance to H2O and SO2 and up to 92% NO conversion at 270 °C with 200 ppm SO2 added over 25 h, which suggests that it is a promising industrial catalyst for mid-low temperature NH3–selective catalytic reduction (SCR) reaction.

A bacterial strain, Arthrobacter oxydans (B4), capable of degrading benzo[a]pyrene (BaP) in water body, was isolated from a polycyclic aromatic hydrocarbons-contaminated site. Effects of different factors, such as reaction time, pH value, temperature and organic nutrients, on BaP biodegradation by the strain B4 were studied. After 5 d treatment, the concentration of BaP in mineral salts medium was reduced to 0.318 mg L−1, compared to the initial concentration of 1.000 mg L−1. There was a process of acid formation during the degradation with pH falling from initial 7.01 to 4.61 at 5 d, so keeping the water body under slightly alkaline condition was propitious to BaP degradation. Strain B4 efficiently degraded BaP at 20 to 37 °C with addition of organic nutrients. The biodegradation and transformation of BaP mainly occurred on cell surfaces, and extracellular secretions played an important role in these processes. Fourier transform infrared spectroscopy and gas chromatograph-mass spectrometer analyses of metabolites showed that ring cleavage occurred in the BaP degradation process and the resulting metabolically utilizable substrates were generated as sole carbon sources for B4 growth. Furthermore, mineralization extent of metabolites was verified by determining the total organic carbon and inorganic carbon in the degradation system.

In the paper, Cd1-xZnxTe polycrystalline films have been prepared by co-evaporation, which can control the zinc content, using CdTe and ZnTe as the evaporation sources. The cubic phase in these films as-deposited and annealed has been demonstrated by XRD. The XRD peaks of Cd1-xZnxTe films are always between the corresponding peaks of CdTe and ZnTe. According to Vegard Formula, x values of Cd1-xZnxTe films have been confirmed from XRD data, which shows that both the calculated and experimental x values are almost identical. The optical transmission of Cd1-xZnxTe films has been measured, and the optical energy gaps have been calculated from the transmission. The band gaps vary in a quadratic way with x values, and increase with annealing temperatures. When application of Cd1-xZnxTe film as a buffer of around 80nm thick in CdS/CdTe solar cells, the structure of the cells becomes CdS/CdTe / Cd1-xZnxTe / ZnTe:Cu and their average conversion efficiency is improved by 40% where x is in the range of 0.55 to 0.65. The mentioned above results are discussed.