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The CS-TPP nanoparticles were synthesized and their efficiency for removal of arsenic (V) ions at the optimum conditions was investigated. The optimum conditions for CS-TPP nanoparticles were obtained with the mass ratio of tripolyphosphate to chitosan of 1: 2 and pH = 5.0. The experimental data for the adsorption of As (V) ions followed the Freundlich adsorption isotherm and the maximum adsorption capacity was 77 mg/g at pH = 6.0. All isotherm experiments were performed at room temperature (25 °C). The crosslinking of sodium tripolyphosphate with the chitosan led to a decrease in crystallinity of the formed particles which then resulted in an improvement in metal ion sorption properties.

This study was conducted to evaluate the potential of the bleached bagasse, cellulose, and nanofiber cellulose to remove methylene blue (MB) from aqueous solution. The morphology of adsorbents surface and their functional groups were examined by using scanning electron microscope and Fourier transform infrared spectroscopy techniques, respectively. In a batch mode study at 25°C temperature, the effects of initial dye concentration, contact time, adsorbent dose, and solution pH on adsorption performance were investigated. The results showed that the percent of MB removal increases by increasing pH and also by increasing sorbent dosage and decreasing initial dye concentration. The adsorption kinetics and equilibrium data were in good agreement with the pseudo-second-order kinetic model and Freundlich adsorption isotherm, respectively. The removal of MB was better and more effective with cellulose and cellulose nanofiber as compared with the bleached bagasse. The regeneration of cellulose and nanofiber cellulose loaded with MB was investigated using electrochemical method under different operating conditions. The results showed that the electrochemical process efficiency is more than 60 for regeneration adsorbents. © 2018 Desalination Publications. All rights reserved.

Presence of aluminum residues in treated water has various health and environmental consequences such as neurotoxicity and possibly Alzheimer’s disease. This study investigated the effects of coagu-lation/flocculation/sedimentation processes using alum as a coagulant in conjunction with Moringa oleifera coagulant protein (MOCP) as coagulant aid on alkalinity and hardness as well as removal of metal ions and turbidity from turbid water. In this study, MOCP was synthesized and used as a new method of treating turbid water. A conventional jar test apparatus was utilized for the tests. Optimal dosage for MOCP was found at pH of 7–7.5 for all turbidities. Maximum turbidity removal of 99 was achieved. MOCP significantly reduced the required dosage of alum. The values of TOC in treated water in low, medium and high turbidity were 0.55, 0.5 and 0.65 mg L–1, respectively. The efficiency of metal ion removal in the present study was as follows: Fe2+ > Cu2+ > Zn2+ > Mn2+. We demonstrated that this method is an efficient approach for optimization of the coagulation-flocculation process in the treatment of raw water. © 2018 Desalination Publications. All rights reserved.

This study investigated the effect of dietary supplementation of probiotic Pedicoccus acidilactici and nucleotide (separately or combined) on growth performance, intestinal microbiota, hemato-immunological parameters, and immunity response in goldfish (Carassius auratus). Fish (average weight 5–6 g) were acclimatized and divided into eight experimental diets supplemented with P. acidilactici of different concentrations (0.1, 0.2, and 0.3% diet) and nucleotides (0 and 0.5% diet) for 6 months. Fish fed with experimental diets showed significant differences in terms of final weight, weight gain, feed conversion ratio, daily growth rate, and condition factor when compared to control diet (P

This investigation was focused on the physico-chemical characterization of the leachate generated by the fine fraction (

Degradation of diclofenac (DCF) from aqueous solution was investigated by the heterogeneous electro-Fenton (EF) process using magnetic single-walled carbon nanotubes (MSWCNTs) as a new catalyst. The effect of parameters including initial pH, current density, initial catalyst concentration, the initial concentration of DCF and air flow rate on the efficiency of DCF removal and electrochemical production of H2O2 were studied. A removal efficiency of 97.8% for DCF and 71.12% for COD was obtained at an initial pH of 5, current density of 20 mA/cm2, MSWCNTs concentration of 80 mg/L, DCF concentration of 10 mg/L, air flow rate of 1 mL/min and reaction time of 120 min. Regarding the removal of DCF and COD, and production of H2O2, the heterogeneous EF process with MSWCNTs catalyst showed higher activity and efficiency than other electro-catalytic degradation systems. The stability tests of MSWCNTs after 5 time application confirmed its performance potential for long-term degradation of DCF in aqueous solutions. Intermediate products such as 2,3-dichlorobenzene and 2,4-dichlorophenol were identified by gas chromatography-mass spectrometry (GC–MS). Based on the identification of reactive species and the intermediate products, a possible mechanism of removal and degradation pathways for DCF was suggested.

The aim of this study was to determine the presence and nature of bacterial flora on hearing aids earmoulds in a children's population. The study population consisted of 119 children referred to Imam Ali and Rudaky Schools in Ahvaz, Iran. Three samples were taken from surface of hearing aids earmoulds; canal in hearing aid wearers and ear without hearing aids earmoulds. The samples were cultured directly onto blood agar and MacConkey agar plates. According to preliminary examination, necessary standard biochemical tests were performed on grown bacteria and the organisms were identified as per standard identification criteria. Totally, 66 samples (61.1%) from hearing aids earmoulds and 124 samples (52.1%) from both ear canal without hearing aids earmoulds were culture positive, which 73 (58.9%) and 51 (41.1%) were from right and left ears, respectively. The majority of isolated bacteria from earmoulds were Coagulase-Negative Staphylococci (CNS) 40 (60.6%) and Polybacterial flora 14 (21.2%) and the least isolated bacteria were Pseudomonas aeruginosa and Staphylococcus aureus. In conclusion, although the majority of isolated bacteria were common normal flora of the ear, however a few pathogens were isolated as well. So, it is very important to educate the people with hearing aids earmoulds about proper cleaning and disinfection procedure to prevent any serious ear canal infection.

The aim of the present study was to investigate the incidence of fungal and bacterial contaminations of in-use eye drop products in the teaching department of ophthalmology, Imam Khomeini Hospital, Ahvaz. Two hundred and eighty seven eye drop bottles were randomly collected at the end of day 1, day 2, day 3, day 4 and day 7 of use. The eye drop residues, swabs from internal caps and droppers were inoculated onto MacConkey agar, blood agar and Sabouraud's dextrose agar. The identification of the recovered organisms was accomplished using standard microbial identification techniques. The incidence of microbial contamination of in-use eye drop products was 17.8%, with the highest rate (24.6%) and the lowest rate (9.0%) noted with day 1 and day 3 samples, respectively. The most contaminated part of the eye drop products was the caps (45.9%) followed by droppers (41.0%) and residual contents (13.1%). Considering mendicants contents, those with pilocarpine (41.7%) had the highest rate of contamination followed by atropine (31.8%), tropicamide (28.6%) and betamethasone (23.3%). Our study revealed the potential risk of contamination of in-use eye drop products in hospitals, but we did not find a direct relationship between usage duration and contamination rate.

Acetylcholinesterase (AChE) is responsible for the rapid hydrolytic degradation of the neurotransmitter acetylcholine into inactive products choline and acetic acid. The purpose of this study was to examine the effect of carbaryl and dichlorvos on the activity of AChE. In this experimental study, 60 samples of free and immobilized form of AChE were prepared. Determination of AChE activity followed the Ellman’s method with modifications. Briefly, 200 µl of the enzyme solution was combined with 400 µl of 25 mM phosphate-buffered saline, 200 µl of DTNB [5,5′-dithio-bis(2-nitrobenzoic acid)], and 200 µl of 300 μM acetylthiocholine iodide. Triplicate (1000 µl) samples were transferred to clean 1.5-ml centrifuge tubes, mixed, and held on ice until analysed and the change in absorbance was measured. For inhibition studies, substrate solutions were pre-incubated with dichlorvos and/or carbaryl. Dichlorvos and carbaryl were used at the concentrations of 100 and 500 μM. The activity was evaluated at 412 nm using Ceceil, CE 1020 spectrophotometer. Phosphate buffer (pH 7.35) was used for blanks. AChE activity was quantified as mM/ml/min. AChE activity of free form is more affected by Dichlorvos (0.09 ± 0.03 mM/ml/min) than immobilized form (0.19 ± 0.02 mM/ml/min). AChE activity of free form is more affected by carbaryl (0.11 ± 0.01 mM/ml/min) than immobilized form (0.1 ± 0.04 mM/ml/min). Comparison of mean AChE activity showed that the activity of the enzyme in presence of dichlorvos and carbaryl was significantly lower compared to controls. To calculate the significance of the difference, the t-test for paired values was applied. The results of our study indicate that dichlorvos and carbaryl cause decrease in AChE activity for both free and immobilization form of enzyme. It is therefore concluded that measuring AChE activity is a way to evaluate poisoning with carbaryl and dichlorvos.