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Objectives: This study aimed to investigate the effects of six-week continuous training (CT) and high-intensity interval training (HIIT) protocols on brain superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities and their associations with short-, mid-, and long-term memory in albino Wistar rats. Methods: In this study, 18 male albino Wistar rats (5 months old) were randomly assigned to three equal (n = 6) groups of sedentary control (SC), CT, and HIIT. Both CT and HIIT regimens were performed for 6 consecutive days per week for 6 weeks. Results: Both HIIT and CT regimens increased short-, mid-, and long-term memory, and the alterations were greater following HIIT than CT. In addition, both HIIT and CT regimens significantly increased SOD activity, with a higher elevation following HIIT than CT. Moreover, brain SOD activity positively correlated with short-, mid-, and long-term memory. However, neither CT nor HIIT had a significant effect on brain GPX and CAT activities. Conclusions: The HIIT regimen is highly potential, as opposed to the CT regimen, to improve memory function through a greater increase in the SOD activity of the brain.

In this study, a sensitive and selective sensor is constructed to measure the melamine (MEL) using molecular imprinting polymer (MIP) technique. Chemical and electrochemical techniques are used to construct the MIP and quantitative measurements. The constructed sensor was modified with GO-Fe3O4@SiO2 nanocomposite. Screening and optimization of factors are done using statistical methods, including Plackett–Burman design (PBD) and central composite design (CCD). Under the optimized conditions, an MIP sensor showed a linear range from 5.0 × 10−7 to 1.0 × 10−5 M MEL concentration with a correlation coefficient (R2) of 0.9997. The limit of detection was obtained (0.028 µM) with a highly reproducible response (RSD 2.15%, n = 4). The electrochemical sensor showed good results for the determination of MEL in food samples.

Over the last decade, polyoxometalates (POMs) have attracted extensive attention as homogeneous and heterogeneous catalysts used for organic transformation. The most important feature of POMs is the possibility of the catalyst design at atomic/molecular levels. They could also be used as multifunctional catalysts, based on different metal atoms and heteroatoms in their structure, counter cations, and second structures. In this review, application of the Keplerate-type giant nanoporous isopolyoxomolybdate (NH4)42[Mo VI 72Mo V 60O372-(CH3COO)30(H2O)72], denoted {Mo132} was reviewed in the synthesis of many organic reactions as a heterogeneous solid acid catalyst, which significantly improved the synthesis condition of various organic reactions in the recent years from 2013 to 2019.

A solid-phase microextraction (SPME) technique using steel fiber coated with polypyrrole (PPY) was developed for UV-Vis determination of citalopram in blood serum. The coating was prepared using a three-electrode electrochemical system from an acetonitrile/aqueous (ACN/H(2)O) oxalic acid solution containing 0.01 M of pyrrole monomer by applying a potential range (0-1.3 V) for 25 min. In order to obtain an efficient film of PPY, experimental parameters related to the coating process were optimized, specifically deposition potential, concentration of monomer, and number of cycles. The effects of various parameters on the efficiency of the SPME process such as extraction time, stirring speed, adsorption and desorption temperature, desorption solvent, and pH of desorption solution were also studied. The coating was stable and adhered to the surface of the steel fiber. The method was linear over about three orders of magnitude with an average correlation coefficient of 0.97. Spiking of blank samples with 0.2 μg/mL citalopram afforded a recovery of 84% with a precision of 10.2%. A limit of detection of 0.046 μg/mL (based on S/N = 3) was obtained in the linear dynamic range of 0.046-2.0 μg/mL. The proposed method was applied to monitor citalopram in serum samples.