Effects of organophosphate, diazinon on some haematological and biochemical changes in Rutilus frisii kutum (Kamensky, 1901) male brood stocks

The acute toxicity and effects of diazinon on some haematological parameters of kutum (Rutilus frisii kutum, Kamensky, 1901) weighing 613.33 ± 157.06 g were studied under static water quality conditions at 15 °C ± 2 ºC. These experiments were carried out based on the standard TRC, 1984 method over 4 days, and controlled for the effective water physicochemical factors having pH ranges of 7-8.2, total hardness 300 mgl^-1 (CaCO3), dissolved oxygen 7 mgl^-1. The results showed that the 96h LC50 value of diazinon was 0.4 mgl^-1 and that the maximum allowable concentration (MAC) value of this toxin was 0.04 mgl^-1. The second stage of experiments consisted of four treatments: LC0: 0 as blank, treatment A with a concentration of LC1: 0.107 mgl^-1, treatment B with a concentration of LC5: 0.157 mgl^-1, treatment C with a concentration of MAC value: 0.04 mgl^-1. Male brood stocks of R. frisii were treated with these concentrations for 45 days. The results showed that long-term exposure to diazinon causes a decrease in the erythrocyte count (RBC), haemoglobin (Hb), haematocrit (PCV), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), leucocyte count (WBC), lymphocyte, testosterone, iron (Fe), sodium (Na), lactate dehydrogenase (LDH) and cholinesterase (CHeS) (P0.05). The results showed that long-term exposure to low concentrations of diazinon causes changes in some haematological and biochemical parameters of R. frisii male brood stocks

Acute and subchronic toxicological evaluation of Echinophora platyloba DC (Apiaceae) total extract in Wistar rats

OBJECTIVE: Echinophora platyloba DC is a widely used herbal medicine and food seasoning in Iran. It is claimed to exert antimicrobial, antifungal, and antispasmodic effects. Despite the prevalent use of this plant as a food and medicine, there are no reports on its possible toxic effects. To evaluate the safety of E. platyloba, we tested its acute and sub-chronic toxicity in male and female Wistar rats. METHODS: Rats were orally treated with four different single doses of E. platyloba total extract and screened for signs of toxicity two weeks after administration. In the sub-chronic toxicity study, E. platyloba was administered for 45 days. Mortality, clinical signs, body weight changes, hematological and biochemical parameters, gross findings, organ weights, and histological markers were monitored during the study. RESULTS: We found no mortality and no abnormality in clinical signs, body weight, or necropsy findings in any of the animals in the acute study. The results of the subchronic study showed no significant difference in hematological parameters in either sex. There was a significant increase in lactate dehydrogenase in the female groups. A significant increase in the relative lung weight of female rats was noted at 500 mg/kg. Histopathological examinations revealed intra-alveolar hemorrhage in the male rats (500 mg/kg). In the females, congestion of the alveolar capillaries (at 500 mg/kg) and liver bridging necrosis (at 200 mg/kg) were significantly increased. CONCLUSION: The no observed adverse effect level of E. platyloba was determined to be 200 and 50 mg/kg for male and female rats, respectively

Optimization of a power electronic structure for hybrid Fuel Cell/Ultracapacitors vehicle

International audienceThis paper deals with the optimization of a parallel hybrid Fuel Cell (FC)/ Ultracapacitors (UCs) power source for automotive applications. The aim of this hybridization and its control are to fulfil the load requirements as well as to comply with the component constraints (high efficiency, reduced weight and cost, etc.). First, a classical hybrid architecture using FC/UCs and a two-converter structure is presented. After that, power requirements for automotive applications are analyzed, and the load power demands for the FC/UCs sources are deduced. Secondly, the model-based design approach is used for the optimization, and a selection of the main components to be optimized is presented. Thus, the simulation model and the control strategy are detailed. This model has been validated experimentally. Finally, an optimization algorithm is designed using Parallel Computing and the Genetic Algorithm toolbox of Matlab/Simulink. The retained criterion is based on the reduction of the total volume of the system

Nonlinear vibration of fractional viscoelastic micro-beams

Nonlinear vibration of a fractional viscoelastic micro-beam is investigated in this paper. The Euler–Bernoulli beam theory and the nonlinear von Kármán strain are used to model the beam. The small-scale effects are considered by employing the Modified Couple Stress Theory (MCST). The viscoelastic material of the beam is modeled via the fractional Kelvin–Voigt model. Utilizing the Hamilton's Principle, a partial fractional differential equation is derived as the governing equation of motion. The Finite Difference Method (FDM) and the Galerkin method are used together for solving the partial fractional differential equation. The FDM is utilized to discretize the time domain, and the Galerkin method is employed to discretize the space domain. In this paper, the FDM and the Shooting method are coupled together to find the periodic solution of the fractional micro-beam and draw the corresponding amplitude–frequency curve. The effects of the order of the fractional derivative, viscoelastic model, and the micro-scale are studied numerically here in this study. Numerical simulations suggest that, the effect of the fractional derivative is very strong and must be considered for modeling the viscoelastic behavior; especially when the amplitude is high. Results also show that the effects of the nonlinear viscoelastic part are considerable when the amplitude is high; this may happen when the excitation frequency is near the natural frequency, at which the maximum amplitude occurs

"Repellent Effect of Extracts and Essential Oils of Citrus limon (Rutaceae) and Melissa officinalis (Labiatae) Against Main Malaria Vector, Anopheles stephensi (Diptera: Culicidae)"

Repellet effect of extracts and essential oils of Citrus limon (L.) Burm.F., (lemon) and Melissa officinalis, (balm) were evaluated against Anopheles stephensi in laboratory on animal and human and compared with synthetic repellent, N,Ndiethyl- 3-methylbenzamide (Deet) as a standard. Results of statistical analysis revealed significant differences between oils and extracts (P< 0.05) against the tested species, thus oils were more effective than extracts. There was no significant difference between Deet and lemon oil, whereas the difference between lemon and melissa oils was significant. Relative efficacy of lemon oil to Deet was 0.88 whereas it was 0.71 for melissa oil. The results were found marginally superior in repellency for animals than human. Due to advantages of botanic compounds to synthetic compounds we recommend lemon essential oil as an effective alternative to Deet with potential as a means of personal protection against mosquito vectors of disease