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The aim of this study was to evaluate the effects of different concentrations of lycopene and cysteamine on characteristics of sperm, liquid peroxidation and enzymatic activities in seminal plasma of canine semen preserved at 5°C for 72 hr. The semen samples were divided into eight aliquots: control, control sham (dimethyl sulfoxide 5%), lycopene groups (250, 500 and 750 µg/ml) and cysteamine groups (2.5, 5 and 10 mM). Motility, viability, membrane integrity, DNA integrity, total antioxidant capacity (TAC) and malondialdehyde (MDA) levels were evaluated. Progressive motility and total motility were higher with the 500 and 750 µg/ml lycopene concentrations, respectively, compared to the control group and the cysteamine groups following 72 hr of storage in the liquid storage. Motility characteristics, viability and hypo-osmotic swelling test (HOST) percentages were significantly improved in 500 µg/ml lycopene compared to other groups. The 500 and 750 µg/ml lycopene concentrations, respectively, showed significantly reduced percentages of spermatozoa with DNA integrity compared to the control group. The 500 and 750 µg/ml lycopene concentrations, respectively, led to the significant decrease of MDA levels. The 500 µg/ml lycopene enhanced TAC levels after 48 and 72 hr that was not observed in other groups. In conclusion, the findings of this study showed that lycopene supplementation in canine semen extenders improved canine semen parameters and TAC levels and decreased MDA levels in the chilling process.

Software‐defined networking (SDN) is a modern approach for current computer and data networks. The increase in the number of business websites has resulted in an exponential growth in web traffic. To cope with the increased demands, multiple web servers with a front‐end load balancer are widely used by organizations and businesses as a viable solution to improve the performance. In this paper, we propose a load‐balancing mechanism for SDN. Our approach allocates web requests to each server according to its response time and the traffic volume of the corresponding switch port. The centralized SDN controller periodically collects this information to maintain an up‐to‐date view of the load distribution among the servers, and incoming user requests are redirected to the most appropriate server. The simulation results confirm the superiority of our approach compared to several other techniques. Compared to LBBSRT, round robin, and random selection methods, our mechanism improves the average response time by 19.58%, 33.94%, and 57.41%, respectively. Furthermore, the average improvement of throughput in comparison with these algorithms is 16.52%, 29.72%, and 58.27%, respectively.

In this study, adaptive neuro-fuzzy inference system (ANFIS) and genetic algorithm–artificial neural network (GA-ANN) models were used to predict inactivation of Salmonella enteritidis by ultrasound. The effect of amplitude levels, duty cycles and irradiation time of ultrasound on inactivation of S. enteritidis was investigated. The inactivation rate of S. enteritidis was increased by intensifying the amplitude levels and the best inactivation was achieved at 37.5 μm amplitude that S. enteritidis population was reduced to 1.67 cfu/mL. The high inactivation rate of S. enteritidis was achieved under duty cycle of 0.7:0.3, with reduction of population to 1.02 cfu/mL. The overall agreement between ANFIS predictions and experimental data was also very good (R2 = 0.974). The developed GA-ANN, which included 12 hidden neurons, could predict S. enteritidis population with low mean squared error, normalized mean squared error and mean absolute error equal to 0.083, 0.023 and 0.200, respectively. The results indicated that both GA-ANN and ANFIS models could give good prediction for the population of S. enteritidis. Sensitivity analysis results showed that ultrasound time was the most sensitive factor for the prediction of S. enteritidis population. Practical Applications Microbial inactivation by thermal treatment does damage to the organoleptic properties of foods. However, using ultrasound (US) for microbial inactivation minimizes this change. Generally, the advantages of US over thermal treatment are minimal flavor loss, significant energy saving and greater homogeneity.

A dynamic model for the wind flow in wind farms is developed in this paper. The model is based on the spatial discretization of the linearized Navier–Stokes equation combined with the vortex cylinder theory. The spatial discretization of the model is performed using the finite difference method, which provides the state-space form of the dynamic wind farm model. The model provides an approximation of the behavior of the flow in the wind farm and obtains the wind speed in the vicinity of each wind turbine. Afterwards, the model is validated using measurement data of Energy research Center of the Netherlands’ Wind turbine Test site in Wieringermeer in the Netherlands and by employing the outcomes of two other wind flow models. The end goal of this work is to present the wind farm flow model by ordinary differential equations, to be applied in wind farm control algorithms along with load and power optimizations. Copyright © 2013 John Wiley & Sons, Ltd.

With more than two billion infected people, from whom 350 to 400 million suffer from chronic infection, hepatitis B virus (HBV) is still a major health problem worldwide. As dental treatment puts both dentists and patients at a higher risk of HBV infection, dentists can play an important role in preventing HBV transmission in dental settings. This study was performed to evaluate dental students' awareness and practice regarding HBV-related issues and to compare the results obtained from different academic years. One hundred and forty-two questionnaires consisting of questions on students' knowledge of HBV and preventive measures against this virus were completed by third- to sixth-year dental students of Tehran University of Medical Sciences (TUMS), Tehran, Iran. Overall, a relatively good level of knowledge was observed amongst this population. However, students' answers to practice questions were less satisfying. It is noteworthy that in some cases students of higher academic years showed less awareness. This finding highlights the necessity of continued infection control education. TUMS students must complete an infection control workshop before they start their clinical education. The authors propose that such training at the beginning of each academic year would be worthwhile.