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Volatile N-nitrosamines (VNAs) are probably and possibly carcinogenic compounds to humans and widely found in processed meat products. In this study, the dietary exposure distribution and probabilistic cancer risk for main VNAs (N-nitrosodimethylamine, N-nitrosodiethylamine, N-nitrosomethylethylamine, N-nitrosopiperidine, N-nitrosodibutylamine, and N-nitrosodi-n-propylamine) were calculated by Monte Carlo simulation (MCS). The lowest and highest mean concentrations of these six NAs were related to NDBA and NDEA as 0.350 and 2.655 μg/kg, respectively. In the 95th percentile, chronic daily intake of total VNAs for children (3–14 years) and adults (15–70 years) were calculated to be 2.83 × 10−4 and 5.90 × 10−5 mg/kg bw/day, respectively. The cancer risk caused by the consumption of chicken sausages was less than 10−4, indicating low concern for the Iranian population. According to principal component analysis and heat map results, NDEA, NPIP and frying showed a positive correlation, highlighting that the variables follow a similar trend. [ABSTRACT FROM AUTHOR]

Main group of contaminants including toxic compounds be formed during food processing and packaging (incidental group) and fungal toxins have been listed as critical challenge for food safety and human health. Because of absorption and transferring of these compounds into the human body and accumulation of them in different organs, several chronic diseases have been observed. The levels of these toxicants have been seriously monitored using analytical techniques. In this review, formation mechanism, toxicological effect and analytical methods of biogenic amines, furfural, hydroxymethylfurfural, polycyclic aromatic hydrocarbon, acrylamide, bisphenol A, nitrosamine and aflatoxin were discussed in different food samples. [ABSTRACT FROM AUTHOR]

In this article, a multi-crack detection method, which is based on natural frequency changes and the concept of modal strain energy, is for the first time developed for the general cross-section swept tapered wings under coupled bending-torsional vibration and applied to the solid and thin-walled airfoil cross-section wings. The presented method is able to handle the problems with an unknown number of cracks and predicts the number of existent cracks, their locations and depths by optimization of an appropriate objective function. The stress intensity factors of airfoil-shaped crack surfaces are obtained using an approximation method. Inputs of the detection method are natural frequencies of uncracked and cracked wings which are calculated by using a mathematical model and finite element method software ANSYS, respectively, and validated by comparison with former research studies. In the mathematical model, the Rayleigh–Ritz method is used to calculate the coupled bending-torsional mode shapes of the uncracked wing and their corresponding natural frequencies. Results demonstrate that the proposed method has precisely predicted the number, locations and depths of cracks in all case studies. [ABSTRACT FROM AUTHOR]

The safety of doner kebab as a traditional Middle East tasty food can threaten via the formation of dangerous compounds such as heterocyclic aromatic amines during heat process. In this regard, the current investigation was devoted to measuring of 4 HAAs (2‐amino‐3,4‐dimethylimidazo[4,5‐f]quinoline (MeIQ), 2‐amino‐3,8‐dimethylimidazo[4,5‐f]quinoxaline (MeIQx), 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP), and 2‐amino‐3‐methylimidazo[4,5‐f]quinoline (IQ)) in doner kebab samples with an innovative microextraction technique combined with high‐performance liquid chromatography. The limit of detection was in the range of 4.8 and 5.3 ng/g, while relative standard deviations were between 6.5% and 8.3%, and recoveries were calculated in the range of 89%–97%. The most and the least total mean values of HAA levels were 13.30 ng/g for MeIQx and 5.0 ng/g for IQ. The proposed method showed a high capability to extract trace amount of HAAs from a complex matrix such as doner kebab. Also, this technique is easy, high sensitive, selective, accurate and efficient. [ABSTRACT FROM AUTHOR]

Moghadasi, M.; Barzegar, F.; Nuri, R. Changes of plasma adipocyte fatty acid binding protein levels following 8 weeks aerobic exercise. Brazilian Journal of Biomotricity. v. 7, n. 4, p. 150-155, 2013. The aim of this study was to examine the changes of plasma adipocyte fatty acid binding protein (A-FABP) levels following 8 weeks aerobic exercise in female athletes. Twenty female karate athletics were randomly assigned to one of the exercise group (n=10) or control group (n=10). The training group performed endurance training 3 days a week for 8 weeks at an intensity corresponding to 50-60% individual maximum oxygen consumption for 45 min. Body mass and BMI increased (P<0.05) after 8 weeks aerobic exercise compared to the control group. For WHR, body fat percentage and maximal oxygen consumption there were no significant difference between the exercise group and the control group. The results showed that A-FABP, fasting glucose and insulin and insulin resistance determined by HOMA-IR did not change in the exercise training compared with the control group. In conclusion, serum A-FABP levels were not affected by 8 weeks moderate intensity aerobic exercise in female athletes. [ABSTRACT FROM AUTHOR]

Introduction: Nicotine, a highly addictive substance, is naturally produced in the Solanaceae family of plants, particularly tobacco. The presence of nicotine in plant foods has adverse effects on the lungs, kidneys, heart, and reproductive system., Objective: A novel three-phase microchip flat electromembrane coupled with online high-performance liquid chromatography (HPLC) was developed to analyze nicotine in tomato, mushroom, eggplant, bell pepper, and red pepper., Methods: The microchip was connected to the HPLC in online mode. All effective variables were optimized to achieve the best extraction response. The use of electric potential and 2-nitrophenyl octyl ether -5% di(2-ethylhexyl) phosphate as a modified supported liquid membrane (SLM) increased the sensitivity and selectivity., Results: The optimal extraction voltage, extraction time, and ion balance were 40 V, 10 min and 0, respectively. The dynamic linear range was 0.5-1000 ng g -1 . The obtained recovery, relative standard deviation, and enrichment factor were 98%, 7%, and 35, respectively. The limits of detection 0.4 ng g -1 and the limits of quantification were obtained 1.3 ng g -1 . The highest (105.0 ng g -1 ) and lowest (3.4 ng g -1 ) concentrations of nicotine were obtained for eggplant and tomato, respectively., Conclusion: Selective electromembrane extraction of nicotine from the donor phase to the acceptor phase was performed by optimizing the main variables influencing the method mechanism. The new channel design in this analytical system and online injection increased efficiency, stability, and repeatability. The results revealed that this method is capable for the efficient determination of trace amount of nicotine in edible vegetables., (© 2024 John Wiley & Sons Ltd.)