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Organic pollutants, such as toluene and xylene, in industrial wastewater negatively impact the environment. Membrane treatment is one of the best methods to reduce impurities in wastewater. Existing membranes that coat the water surface with hydrophilic material only effectively resist the initial fouling, resulting in poor oil and water selectivity. Here we report a simple and efficient method to enhance the water flux and antifouling properties of polyvinylidene fluoride (PVDF) membranes. This method involves developing and applying Catechol-Fe(III) complexes with a rough surface to the PVDF surface. Forming Catechol-Fe(III) complexes on the surface better anchors them to the membrane than the dip-coating method. The PVDF membranes with rough Catechol-Fe(III) complexes are superoleophobic, with an oil contact angle of 152 ° and high permeability, with pure water flux of 10487 L m ‐ 2 h ‐ 1 b a r ‐ 1 and 1 wt% toluene in water emulsion flux of 4697 L m ‐ 2 h ‐ 1 b a r ‐ 1 . Overall, the straightforward manufacturing process, increased permeability, and outstanding antifouling capabilities of the PVDF membrane incorporating rough nanoparticles offer promising prospects for designing and implementing suitable membranes for oil in water emulsion separation applications. [Display omitted] • Superoleophobic PVDF membrane (RN-m) are fabricated with catechol-Fe3+coordination. • The RN-m exhibits a high-water flux (10487 Lm−2h−1) and low surface energy (0.05 mNm−1). • The RN-m shows emulsions separation efficiency up to 98.3% and fluxes up to 4798 Lm−2h−1. • The membrane can be successfully reused 25 times and flux not declined by more than 5%. [ABSTRACT FROM AUTHOR]

Abstract: Oligomeric and polymeric procyanidins have been reported to possess different antioxidant capacities. However, the intracellular antioxidant mechanisms of oligomeric and polymeric procyanidins are still poorly understood. In this study, we evaluated the cytoprotective effects of the oligomeric procyanidin fraction (OPF) and the polymeric procyanidin fraction (PPF) from grape seeds against the oxidative damage induced by tert-butyl hydroperoxide (TBHP) in HepG2 cells. The levels of cellular reactive oxygen species (ROS), cellular lipid peroxidation, glutathione (GSH), and antioxidant enzyme activities were measured as biomarkers of cellular oxidative status. HepG2 cells were treated with different concentrations of procyanidin samples (0–20μg/ml) for 6h prior to treatment with TBHP for 3h. The incubation of HepG2 cells with TBHP led to an approximately 60% decrease in cell viability. However, pretreatment of the cells with the samples, at 5–20μg/ml, rescued cell viability in a dose-dependent manner. Cellular generation of ROS, formation of malondialdehyde (MDA), and depletion of GSH were reduced by OPF and PPF. Moreover, TBHP treatment increased the activities of glutathione peroxidase (GPx), catalase (CAT), and superoxide dismutase (SOD). However, a 6h pretreatment with each of the samples at 20μg/ml significantly decreased the activities of these enzymes. These results clearly showed that treatment with OPF and PPF protected against oxidative damage by modulating ROS production, GSH levels, MDA generation, and antioxidant enzyme activities in HepG2 cells. [Copyright &y& Elsevier]

Abstract: Chrysanthemum zawadskii var. latilobum (CZ) has been widely used as a tea in Korea. In this study, we investigated the involvement of anti-inflammatory haem oxygenase-1 (HO-1) in the inhibitory activity of a CZ leaf extracts on nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. At the highest concentration of CZ leaf extract (50μg/mL), NO production was 10% of that in LPS-stimulated macrophages, whereas iNOS protein expression was 5% of that in LPS-stimulated macrophages. CZ leaf extract also inhibited iNOS mRNA expression in a concentration-dependant manner, and at 50μg/mL, iNOS mRNA expression was approximately 15% of that in LPS-stimulated cells. The CZ leaf extract induced HO-1 expression in a dose-dependent manner, and blocking HO-1 activity abolished the anti-inflammatory effect of CZ leaf extract. These results suggest that CZ leaf extract has a potent anti-inflammatory activity in RAW264.7 cells through the induction of HO-1. [Copyright &y& Elsevier]

Abstract: The antioxidant and antiproliferative activities of a tocotrienol-rich fraction (TRF) obtained from grape seeds were evaluated. TRF, a mixture of γ-tocopherol and α- and γ-tocotrienol, was prepared from a methanol-soluble fraction of grape seed oils by eluting with 10% ether (v/v) using silica gel chromatography. TRF had significantly higher antioxidant and antiproliferative activities compared to other fractions. TRF showed 3.5-, 40.0-, and 39.0-fold higher ABTS radical scavenging activity, inhibition of lipid peroxidation, and reducing power, respectively, compared to α-tocopherol fraction (5% diethyl ether fraction). TRF had higher antiproliferative activity against MCF7 (81%) and NCI-H460 (76%) cells at a concentration of 1.0mg/ml. The results suggest that TRF from grape seeds has significant health-promoting effects, having excellent antioxidant and anticancer activities. [Copyright &y& Elsevier]

Abstract: The objectives of this study were to determine antioxidant activity of the methanolic extracts from some grains and to investigate relationships between antioxidant activities and antioxidant contents in the extracts. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities, 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical cation scavenging activities, inhibitory effect on lipid peroxidation, chelating activity and reducing power have been used to investigate the relative antioxidant activities of the extracts from grains. The concentrations of total polyphenolics and carotenoids in the extracts were measured by spectrophotometric methods and vitamin E analysis was carried out by HPLC. The methanolic extracts prepared from red sorghum and black rice showed significantly higher antioxidant activities and contained higher polyphenolic contents than other grains such as white rice, brown rice, mungbean, foxtail millet, prosomillet, barley, and adlay. Polyphenolic compounds were the major naturally occurring antioxidants in grains. The correlation coefficient between total polyphenolic content and ABTS radical cation scavenging activity in the extracts was >0.99. However, no relationship was found between antioxidant activities and carotenoids and vitamin E derivatives. [Copyright &y& Elsevier]

Abstract: Background and purpose: To evaluate the effect of an intravenous contrast agent (CA) on dose calculations and its clinical significance in intensity modulated radiation therapy (IMRT) plans for head and neck cancer. Materials and methods: Fifteen patients with head and neck cancer and involved neck nodes were enrolled. Each patient took two sets of computerized tomography (CT) in the same position before and after intravenous CA injections. Target volumes and organs at risk (OAR) were contoured on the enhanced CT, and then an IMRT plan of nine equiangular beams with a 6MV X-ray was created. After the fusion of non-enhanced and enhanced CTs, the contours and the IMRT plan created from the enhanced CT were copied and placed to the non-enhanced CT. Doses were calculated again from the non-enhanced CT by the same IMRT plan. The radiation doses calculated from the two sets of CTs were compared with regard to planning target volumes (PTV) and the three OARs, both parotid glands and the spinal cord, by Wilcoxon’s signed rank test. Results: The doses (maximum, mean, and the dose of 95% of PTV received (D 95%)) of PTV70 and PTV59.4 calculated from the enhanced CTs were lower than those from the non-enhanced CTs (p <0.05), but the dose differences were less than 1% compared to the doses calculated from the enhanced CTs. The doses of PTV50.4, parotid glands, and spinal cord were not significantly different between the non-enhanced and enhanced CTs. Conclusions: The difference between the doses calculated from the CTs with and without CA enhancement was tolerably small, therefore using intravenous CA could be recommended for the planning CT of head and neck IMRT. [Copyright &y& Elsevier]

Abstract: The potential of carbon-related materials, such as carbon nanotubes (CNTs) and graphite nanofibers (GNFs), supported metal catalysts as an electrode for fuel cell application was investigated using the first-principle electronic structure calculations. The stable binding geometries and energies of metal catalysts are determined on the CNT surface and the GNF edge. The catalyst metal is more tightly bound to the GNF edge than to the CNT surface because of the existence of active dangling bonds of edge carbon atoms. The diffusion barrier of metal atoms on the surface and edge is also obtained. From our calculation results, we have found that high dispersity is achievable for GNF due to high barrier against the diffusion of metal atoms, while CNT appears less suitable. The GNF with a large edge-to-wall ratio is more suitable for the high-performance electrode than perfect crystalline graphite or CNT. [Copyright &y& Elsevier]

Purpose: To investigate the feasibility of intensity-modulated radiotherapy (IMRT) as a method of boost radiotherapy after the initial irradiation by the conventional anterior/posterior opposed beams for centrally located non–small-cell lung cancer through the evaluation of dose distributions according to the various boost methods. Methods and Materials: Seven patients with T3 or T4 lung cancer and mediastinal node enlargement who previously received radiotherapy were studied. All patients underwent virtual simulation retrospectively with the previous treatment planning computed tomograms. Initial radiotherapy plans were designed to deliver 40 Gy to the primary tumor and involved nodal regions with the conventional anterior/posterior opposed beams. Two radiation dose levels, 24 and 30 Gy, were used for the boost radiotherapy plans, and four different boost methods (a three-dimensional conformal radiotherapy [3DCRT], five-, seven-, and nine-beam IMRT) were applied to each dose level. The goals of the boost plans were to deliver the prescribed radiation dose to 95% of the planning target volume (PTV) and minimize the volumes of the normal lungs and spinal cord irradiated above their tolerance doses. Dose distributions in the PTVs and lungs, according to the four types of boost plans, were compared in the boost and sum plans, respectively. Results: The percentage of lung volumes irradiated >20 Gy (V20) was reduced significantly in the IMRT boost plans compared with the 3DCRT boost plans at the 24- and 30-Gy dose levels (p = 0.007 and 0.0315 respectively). Mean lung doses according to the boost methods were not different in the 24- and 30-Gy boost plans. The conformity indexes (CI) of the IMRT boost plans were lower than those of the 3DCRT plans in the 24- and 30-Gy plans (p = 0.001 in both). For the sum plans, there was no difference of the dose distributions in the PTVs and lungs according to the boost methods. Conclusions: In the boost plans the V20s and CIs were reduced significantly by the IMRT plans, but in the sum plans the effects of IMRT on the dose distributions in the tumor and lungs, like CI and V20, were offset. Therefore, to keep the beneficial effect of IMRT in radiotherapy for lung cancer, it would be better to use IMRT as a whole treatment plan rather than as a boost treatment. [Copyright &y& Elsevier]

The atomic structure of amorphous Al2O3 has been determined using a molecular dynamics simulation. The local electronic structures of the simulated amorphous structure and of the crystalline structure of Al2O3 were investigated using first principle cluster calculations. The calculated partial densities of states for the two structures are compared with their photoelectron spectra. We find that there is a local oxygen deficiency around Al atoms in amorphous Al2O3, which results in a different local electronic structure in amorphous Al2O3. We also show with our calculations and photoelectron spectroscopy that Al2O3 thin films have both crystalline and amorphous properties. [Copyright &y& Elsevier]

Highlights: [•] The contents of some B vitamins were different in 10 black soybean varieties. [•] The responses of riboflavin and thiamine were most similarly associated in the PCA loading plot. [•] Cotyledon colour factor differently affected the correlation responses. [ABSTRACT FROM AUTHOR]

This study is to elucidate the involvement of anti-inflammatory heme oxygenase-1 (HO-1) in the inhibitory activity of a Chrysanthemum boreale Makino (CB) extract on nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Materials and methods: Cell viability and NO assay were performed. In addition, iNOS expression was detected by Western blotting and real-time PCR. HO-1 expression was also evaluated by Western blotting, and blocking HO-1 activity on NO production was performed. Results: The CB extract at the highest concentration (100μg/ml) significantly inhibited NO production by approximately 90% and suppressed iNOS protein expression by approximately 84.8% compared to LPS-stimulated cells. Furthermore, the CB extract (100μg/ml) inhibited iNOS mRNA expression in a concentration-dependant manner and suppressed iNOS mRNA expression by 94.8%. The CB extract induced the expression of HO-1 in a dose-dependent manner, and blocking HO-1 activity abolished the inhibitory effects of the CB extract. Moreover, the addition of carbon monoxide such as tricarbonyl dichlororuthenium (II) dimmer (RuCO), a byproduct derived from heme degradation, mimicked the inhibitory action of low concentrations of CB extract. Conclusion: These results suggest that a CB extract has potent anti-inflammatory activity in RAW264.7 macrophages involving the induction of HO-1. [Copyright &y& Elsevier]

Abstract: The field emission properties of double-walled carbon nanotubes (DWCNTs) were remarkably improved by decorating their surface with ruthenium (Ru) metal nanoparticles. The Ru nanoparticles were attached effectively on the surface of DWCNTs via a chemical procedure. The Ru-decorated DWCNTs showed lower turn-on voltage, higher emission current density, and improved emission uniformity compared with pristine DWCNTs. The effect of Ru nanoparticles on the work function and density of states was evaluated by the first-principles calculation. The enhanced field emission properties of Ru-DWCNTs were mainly attributed to the Ru nanoparticles which increased the field enhancement factor and the density of emission sites. Our results indicate that the Ru-decorated DWCNTs can be used as an effective field emitter for various field emission devices. [Copyright &y& Elsevier]

Abstract: This paper presents the friction and antiwear characteristics of nano-oil composed of refrigerant oil and fullerene nanoparticles in the sliding thrust bearing of scroll compressors. The nano-oil was evaluated using a sliding thrust bearing tester. The friction coefficient of fullerene nano-oil at the lower normal loads (<∼1200N) under the fixed orbiting speed (∼1800rpm) was ∼0.02, while that of pure oil was ∼0.03, indicating that the fullerene nanoparticles dispersed in the base refrigerant oil improved the lubrication property by coating the friction surfaces. However the difference between friction coefficients for both nano-oil and pure oil was found to be negligible at higher normal load conditions (>∼1200N), indicating that the nanoparticles in the base oil have little effect on the enhancement of lubrication between the friction surfaces. The friction coefficient of nano-oil at various speeds of the orbiting plate in the sliding thrust bearing was found to be less than that of pure oil over the entire orbiting speed ranges between 300 and 3000rpm. This is presumably because fullerene nanoparticles, which were inserted between the friction surfaces, improved the lubricating performance by increasing the lubricant oil viscosity and simultaneously preventing direct metal surface contacts. [Copyright &y& Elsevier]

Abstract: We have carried out the first-principle electronic structure calculations based on density functional theory on InTaO4 in various states, such as pristine, oxygen vacancy, and Ni-doped states. We have found that oxygen vacancy can induce the gap states and Ni-doping can narrow the band gap by generating additional states on the top of the valence band as well as on the top of the gap states. From our calculated results, we have shown that oxygen vacancy can do a crucial role to generate gap states which let InTaO4 absorb the visible light. [Copyright &y& Elsevier]