A Surface‐Charge Study on Cellular‐Uptake Behavior of F3‐Peptide‐Conjugated Iron Oxide Nanoparticles

Surface‐charge measurements of mammalian cells in terms of Zeta potential are demonstrated as a useful biological characteristic in identifying cellular interactions with specific nanomaterials. A theoretical model of the changes in Zeta potential of cells after incubation with nanoparticles is established to predict the possible patterns of Zeta‐potential change to reveal the binding and internalization effects. The experimental results show a distinct pattern of Zeta‐potential change that allows the discrimination of human normal breast epithelial cells (MCF‐10A) from human cancer breast epithelial cells (MCF‐7) when the cells are incubated with dextran coated iron oxide nanoparticles that contain tumor‐homing F3 peptides, where the tumor‐homing F3 peptide specifically bound to nucleolin receptors that are overexpressed in cancer breast cells.     

Hydrolytic Kinetic Resolution of Epoxides Catalyzed by Chromium(III)‐endo,endo‐2,5‐diaminonorbornane‐salen [Cr(III)‐DIANANE‐salen] Complexes. Improved Activity,Low Catalyst Loading

The hydrolytic kinetic resolution (HKR) of terminal epoxides, using chiral chromium(III )‐salen catalysts based on DIANANE (endo,endo‐2,5‐diaminonorbornane), was studied. A broad substrate scope was found for the chromium(III )‐DIANANE catalysts, and very low loadings (down to 0.05 mol %) were needed to achieve high enantiomeric purities of both the remaining epoxides and the product diols (up to >99 % ee). Besides monosubstituted epoxides, 2‐methyl‐2‐n‐pentyloxirane, which is an example for 2,2‐disubstituted epoxides, could be ring‐opened in an asymmetric fashion with water in the presence of an electronically tuned chromium(III )‐DIANANE complex.     

Hybrid polymeric scaffolds prepared by micro and macro approaches

Polymeric scaffolds with complex porous structures were fabricated with two different polymers by combining three fabrication methods in three steps, in which, nonwoven poly(ε-caprolactone) microfibers were obtained with electrospinning and immersed in solvent cast chitosan solution poured in Petri dish to fabricate hybrid polymers, and finally the combined structure was freeze-dried with two different predrying techniques to obtain macropores in the structure. The resulting hybrid polymeric mats were found to have both microfibers and macroporosity due to the electrospinning as well as freeze-drying processes, which resemble the natural extracellular matrix. The optimized scaffolds that predried in the incubator at 40°C for 5?h and then freeze-dried for 24?h exhibited contact angle value of 68.93?±?2.18° with 3.252?±?0.783?MPa Young’s modulus and 0.260?±?0.002?MPa yield strength as well as 1.35-fold cell yield in MRC5 fibroblast cell culture, compared to the commercial tissue culture polystyrene.     

Effect of essential oils treatment on the frozen storage stability of chub mackerel fillets

The effect of bay leaf (BLO), thyme (TO), rosemary (RO), black seed (BSO), sage (SO), grape seed (GSO), flaxseed (FSO) and lemon (LO) essential oil from vegetable extracted on lipid oxidation and some other quality parameter of frozen chub mackerel during frozen storage at ?20°C were examined over a period of 11 months. Taste, odour, texture and overall acceptability of control samples were given ‘unacceptable’ scores by the sixth month. Based primarily on sensory data, the shelf-lives of frozen chub mackerel were found 6 month for samples treated with oil of TO, RO, BSO, SO and LO and 7 month for samples treated with BLO, GSO and FSO. During the 11-months storing process of chub mackerel, the values of pH, total volatile basic nitrogen (TVB-N), trimethylamine nitrogen (TMA-N) both in control group samples and samples treated with oils did not reach to deterioration levels. Thiobarbitüric acid (TBA) and free fatty acid (FFA) values for all treatments remained lower than TBA and FFA values of control samples throughout the 11 month storage period. Particularly, thyme oil treatment is effective in delaying lipid oxidation. Bay leaf, rosemary, sage, lemon, flaxseed and grape seed oils were fallowed.     

Biotreatment of zinc-containing wastewater in a sulfidogenic CSTR: Performance and artificial neural network (ANN) modelling studies

Sulfidogenic treatment of sulfate (2-10g/L) and zinc (65-677mg/L) containing simulated wastewater was studied in a mesophilic (35 degrees C) CSTR. Ethanol was supplemented (COD/sulfate=0.67) as carbon and energy source for sulfate-reducing bacteria (SRB). The robustness of the system was studied by increasing Zn, COD and sulfate loadings. Sulfate removal efficiency, which was 70% at 2g/L feed sulfate concentration, steadily decreased with increasing feed sulfate concentration and reached 40% at 10g/L. Over 99% Zn removal was attained due to the formation of zinc-sulfide precipitate. COD removal efficiency at 2g/L feed sulfate concentration was over 94%, whereas, it steadily decreased due to the accumulation of acetate at higher loadings. Alkalinity produced from acetate oxidation increased wastewater pH remarkably when feed sulfate concentration was 5g/L or lower. Electron flow from carbon oxidation to sulfate reduction averaged 83+/-13%. The rest of the electrons were most likely coupled with fermentative reactions as the amount of methane production was insignificant. The developed ANN model was very successful as an excellent to reasonable match was obtained between the measured and the predicted concentrations of sulfate (R=0.998), COD (R=0.993), acetate (R=0.976) and zinc (R=0.827) in the CSTR effluent.     

Kinetic Stabilization of the Sol–Gel State in Perovskites Enables Facile Processing of High‐Efficiency Solar Cells

Perovskite solar cells increasingly feature mixed‐halide mixed‐cation compounds (FA_1?x?yMA_xCs_yPbI_3?zBr_z) as photovoltaic absorbers, as they enable easier processing and improved stability. Here, the underlying reasons for ease of processing are revealed. It is found that halide and cation engineering leads to a systematic widening of the anti‐solvent processing window for the fabrication of high‐quality films and efficient solar cells. This window widens from seconds, in the case of single cation/halide systems (e.g., MAPbI₃, FAPbI₃, and FAPbBr₃), to several minutes for mixed systems. In situ X‐ray diffraction studies reveal that the processing window is closely related to the crystallization of the disordered sol–gel and to the number of crystalline byproducts; the processing window therefore depends directly on the precise cation/halide composition. Moreover, anti‐solvent dripping is shown to promote the desired perovskite phase with careful formulation. The processing window of perovskite solar cells, as defined by the latest time the anti‐solvent drip yields efficient solar cells, broadened with the increasing complexity of cation/halide content. This behavior is ascribed to kinetic stabilization of sol–gel state through cation/halide engineering. This provides guidelines for designing new formulations, aimed at formation of the perovskite phase, ultimately resulting in high‐efficiency perovskite solar cells produced with ease and with high reproducibility.     

Simultaneous heterotrophic and sulfur-oxidizing autotrophic denitrification process for drinking water treatment: control of sulfate production

A long-term performance of a packed-bed bioreactor containing sulfur and limestone was evaluated for the denitrification of drinking water. Autotrophic denitrification rate was limited by the slow dissolution rate of sulfur and limestone. Dissolution of limestone for alkalinity supplementation increased hardness due to release of Ca²⁺. Sulfate production is the main disadvantage of the sulfur autotrophic denitrification process. The effluent sulfate concentration was reduced to values below drinking water guidelines by stimulating the simultaneous heterotrophic and autotrophic denitrification with methanol supplementation. Complete removal of 75 mg/L NO₃-N with effluent sulfate concentration of around 225 mg/L was achieved when methanol was supplemented at methanol/NO₃-N ratio of 1.67 (mg/mg), which was much lower than the theoretical value of 2.47 for heterotrophic denitrification. Batch studies showed that sulfur-based autotrophic NO₂-N reduction rate was around three times lower than the reduction rate of NO₃-N, which led to NO₂-N accumulation at high loadings.     

Weathering performance of waterborne acrylic coating systems on flat-pressed wood–plastic composites

This study applied coating systems containing two different waterborne acrylic resins with an ultraviolet (UV) absorber on the surfaces of polyvinyl chloride-based flat-pressed wood–plastic composites (WPCs) evaluated and the effects of waterborne acrylic coating on the performance of WPCs in outdoor conditions. The results showed that waterborne acrylic coating systems enhanced the surface quality of WPC. The decrease in flexural strength was found to reach up to 22%, while it was about 25% for modulus. The color changes on the surface decreased by 55% as a result of the UV absorbability of the coating systems. Moreover, the chemical changes in the composites were found to be almost nonexistent in the attenuated total reflection–Fourier transform infrared spectroscopy for WPCs coated with both formulations. The light microscopy images revealed that the coating systems minimized deformation on the surface. In comparison to the control samples, it was seen that the surface roughness of the WPC was also improved by using waterborne acrylic coating systems. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48518.     

Microbiological and chemical quality of different types of salted pearl mullet (Chalcalburnus tarichi Pallas, 1811)

This research aimed to determine microbiological and chemical quality of different types of salted pearl mullet (Chalcalburnus tarichi Pallas, 1811). Samples of salted pearl mullet (C. tarichi Pallas, 1811), produced by six different methods, were obtained from three different local producers at the end of the hunting season of 2016 and 2017 (May–June) with wooden boxes, plastic cans, or in bottom perforated plastic cans. Samples stored in a cold storage (2 ± 2°C) were analyzed in August and September of 2017. Six fish were used in each sampling day and thus the analyses were completed in 18 days. So, 108 fish samples were analyzed (3 producer × 6 method × 3 sample for each method × 2 hunting season). Analysis results were calculated as mean ± SD. One-way analysis of variance was used to determine whether there was a significant difference between the sample groups analyzed, and p < .05 was considered significant. All sample groups were found to be appropriate according to total mesophilic aerobic bacteria count, but one sample group (OS11-old sample, gutted and cleaned fish producted in wooden box according to method 1) included Salmonella spp. and Vibrio parahaemolyticus, it was found to be inappropriate (p < .05). The total volatile basic nitrogen acceptability upper limit (25–30 mg/100 g) were found to be exceeded in three sample groups (OS12-old sample, ungutted, and uncleaned fish producted in wooden box according to method 1, OS31-old sample, gutted, and cleaned fish producted in bottom perforated plastic can according to method 3, OS32-old sample, ungutted, and uncleaned fish producted in bottom perforated plastic can according to method 3) (p < .05) and the tiobarbituric acid index value was found to vary between 13.32 ± 0.08 and 31.43 ± 0.04 μg malondialdehyde/g (p < .05). According to histamine results, all sample groups were determined at acceptable values (p > .05). However, it was determined that the salt amount of the sample groups was very high in raw, and that more than half of the salt amount remained in the samples, even after baked waiting for 3 hr in warm water (p < .05).