Optimization with response surface methodology of biosorption conditions of Hg(II) ions from aqueous media by Polyporus Squamosus fungi as a new biosorbent

Removal of mercury(II) (Hg(II)) from aqueous media by a new biosorbent was carried out. Natural Polyporus squamosus fungus, which according to the literature has not been used for the purpose of Hg(II) biosorption before, was utilized as a low-cost biosorbent, and the biosorption conditions were analyzed by response surface methodology (RSM). Medium parameters which were expected to affect the biosorption of Hg(II) were determined to be initial pH, initial Hg(II) concentration (Co), temperature (T (°C)), and contact time (min). All experiments were carried out in a batch system using 250 mL flasks containing 100 mL solution with a magnetic stirrer. The Hg(II) concentrations remaining in filtration solutions after biosorption were analyzed using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). Based on the RSM results, the optimal conditions were found to be 5.30, 47.39 mg/L, 20°C and 254.9 min for pH, Co, T (°C), and contact time, respectively. Under these optimal conditions, the maximum biosorbed amount and the biosorption yield were calculated to be 3.54 mg/g and 35.37%, respectively. This result was confirmed by experiments. This result shows that Polyporus squamosus has a specific affinity for Hg ions. Under optimal conditions, by increasing the amount of Polyporus squamosus used, it can be concluded that all Hg ions will be removed

Dynamic rheological characterization of salep glucomannan/galactomannan-based milk beverages

The steady flow and viscoelastic properties of glucomannan (salep) and galactomannans (locust bean gum, LBG and guar gum, GG) in milk beverages were investigated at 25 and 50 °C. The consistency index (K), flow behavior index (n), yield stress and thixotropic area were measured as functions of steady shear; elastic modulus (G'), loss modulus (G''), tan ? and complex viscosity (?*) parameters were derived from oscillatory shear experiments. The steady flow behavior of mannan-based milk beverages was observed to be shear-thinning and thixotropic. Galactomannans exhibited greater shear-thinning and thixotropy than glucomannan in milk beverages. The synergistic effect was detected between salep and LBG with highest thixotropy. Increasing the temperature decreased Casson yield stresses of GG but not salep and LBG samples. Similar viscoelastic behavior was observed between salep and LBG, they could be classified as concentrated solutions but GG showed gel-like structure. At low frequencies, high tan ? values were observed for the salep and LBG samples indicating viscous character. On the other hand, GG sample had nearly the same tan ? values through the frequency sweep. Cox-Merz rule was tested to correlate the steady and dynamic viscosities of samples. It was found that Cox-Merz rule was applicable only to LBG-milk beverage among the studied samples. © 2008 Elsevier Ltd. All rights reserved

Oxidative stress biomarkers in liver and gill tissues of spotted barb (Capoeta barroisi Lortet, 1894) living in the river Ceyhan, Adana, Turkey [Ceyhan nehri (Adana-Türkiye)'nde yaşayan benekli siraz (Capoeta barroisi Lortet, 1894)'larda solungaç ve karaciger dokudaki oksidatif stresin biyolojik göstergeleri]

This study was carried out in an agricultural, industrial, domestic, and slaughterhouse area that is also a discharging region of the river Ceyhan just under the crest of the Aslantaş dam. Levels of pollution indicator parameters of the water were observed and their effects on various oxidative stress biomarkers in gill and liver tissues of spotted barb (Capoeta barroisi Lortet, 1894) were investigated. The oxidative stress biomarkers analyzed included superoxide dismutase (SOD), catalase (CAT), and glucose-6-phosphate dehydrogenase (G6PD). Levels of reduced glutathione (GSH) and lipid peroxidation (LPO) were also evaluated. High levels of CAT, G6PD, GST, and GSH activity were found in the liver tissues of fish collected from the river Ceyhan discharging region; it was determined that the region was polluted. Substantially high levels of SOD and LPO (P < 0.05 in gill and liver) were observed. The findings of the present investigation will provide a rational use for oxidative stress biomarkers in aquatic ecosystem pollution biomonitoring. © TÜBİTAK

Removal of Some Heavy Metal Cations from Aqueous Solution by Adsorption onto Natural Kaolin

The adsorption removal of some heavy metal cations such as Cu(II), Zn(II) and Co(II) from aqueous solution onto kaolin has been studied using the batch method with initial metal ion concentrations within the range 15–70 mg/l. The percentage adsorption and equilibrium concentrations were determined by means of atomic absorption flame photometry as a function of adsorbate concentration, pH and temperature. Ion-exchange studies showed that over the complete concentration range studied the adsorption ratios for metal cations adsorbed onto kaolin correlated with the linear forms of the Langmuir, Freundlich and Dubinin—Kaganer—Radushkevich (DKR) adsorption isotherms. The cationexchange capacity of kaolin towards each metal ion studied was evaluated. It was found that the adsorption phenomena depended on the charge density and diameter of the hydrated ion. The equilibrium studies demonstrated that the selectivity of the ions followed the sequence Zn(II) > Cu(II) > Co(II) at pH 7.0. Calculation of thermodynamic parameters such as the standard enthalpy (ΔH 0 ), Gibbs free energy (ΔG 0 ) and entropy (ΔS 0 ) showed that the adsorption of the heavy metal ions studied onto kaolin was an endothermic process which was favoured at higher temperatures. These results show that natural kaolin has a considerable potential for the removal of heavy metal cationic species from aqueous solution and wastewater

Occurrence of the swimbladder parasite Anguillicola crassus (Nematoda, Dracunculoidea) in European eels (Anguilla anguilla) in Ceyhan River, Turkey

European eels (Anguilla anguilla), collected from the Ceyhan River (Adana, Turkey) in 2002, were examined in terms of the presence of swimbladder nematoda. The existence of infection with Anguillicola crassus, a pathogenic swimbladder parasite, was identified in 50 out of 64 specimens. The total number of parasites, prevalence (%), parasite abundance and mean intensity of parasite values of July and November samples were 93, 82.86%, 2-7, 3.31 ± 1.32 and 56, 72.41%, 1-5, 3.20 ± 1.30, respectively. There was no significant histopathological destruction in the internal organs of the infected eels. © TÜBİTAK

An investigation of the effects of pes planus on distal and proximal lower extremity biomechanical parameters and low back pain [Pes planusun dİstal ve proksİmal alt ekstremİte bİyomekanİk parametrelerİ ve bel ağrisi üzerİne etkİlerİnİn İncelenmesİ]

Purpose: The objective of the study was to compare the biomechanical features of the lower extremity, foot structure, and function and low back pain in young sedentary subjects with and without pes planus. Methods: The study was conducted with the participation of 60 sedentary subjects consisting of 30 women and 30 men. The subjects were assigned to two groups as with or without pes planus according to navicular drop test results. The American Orthopaedic Foot and Ankle Society score and Visual Analogue Scale Foot and Ankle Scales were used to evaluate the foot function of the subjects. Muscle shortness and strength tests of the selected muscles, Q angle, and pelvic inclination angle measurements were performed. Oswestry Disability Index was used to evaluate low back pain. The subjects with and without pes planus were compared. Results: There were no significant differences between the subjects with and without pes planus regarding tibialis posterior and peroneal muscle strength, gastrocnemius, soleus and hamstring muscle shortness, Q angle, American Orthopaedic Foot and Ankle Society score, and Visual Analogue Scale Foot and Ankle score (p>0.05). The pelvic inclination angle of the non-dominant side was higher (p=0.042), and Oswestry Disability Index score was higher (p=0.001) in subjects with pes planus compared to those without pes planus. Conclusion: Our results indicated that pes planus may increase pelvic inclination and may cause low back pain, while lower extremity muscle strength, muscle shortness, and foot function were not affected from this case in young sedentary subjects. © 2019 Turkish Physiotherapy Association. All rights reserved