Field observation on the use of PRID®Delta to induce estrus and ovulation in anestrous mares

To advance the time of the first estrus with ovulation, we administered intravaginally a progesterone-releasing devices PRID® Delta to 42 acyclic Arab-Barb mares for 11 days at different seasons: winter (n = 10), spring (n = 14), summer (n = 9) and autumn (n = 9). Twenty-seven of 39 mares that kept their coils responded to the PRID® Delta treatment with estrus and ovulation during the 42-day observation period, in winter (4/10, 40%) mares, in spring (9/13, 69%), in summer (7/7, 100%) and autumn (7/9, 78%) mares (P <0,05). At Day 2 of PRID® Delta treatment, mean initial of progesterone concentrations was significantly increased in all mares in winter (7.20 ± 0.49 ng mL-1), spring (7.30 ± 0.64 ng mL-1), summer (7.5 ± 0.58 ng mL-1 ) and autumn ( 7.60 ± 0.71 ng mL-1) (P <0,05). Total concentration of progesterone (area under curve (AUC)) during the treatment period revealed highest values in spring (67.95 ± 2.40 ng mL-1h-1) followed by autumn (65.20 ± 1.37 ng mL-1 h-1), winter (54.19 ± 7.00 ng mL-1 h-1) and summer 52.23 ± 3.32 ng mL-1 h-1; P < 0.05). In conclusion, administration of the intravaginal device releasing progesterone PRID® Delta was able to induce estrus and ovulation in mares at different times of the year. However, the efficacy of the treatment was not satisfactory in terms of efficacy compared to the season (low response rate in winter) and synchrony of intervals from removal of PRID® Delta to ovulation

Modélisation de l'impact de projectiles sur des installations voisines : couplages mécano-probabiliste

National audienceLes projectiles engendrés lors d'une explosion d'un réservoir sont des menaces pour d'autres équipements environnants et peuvent entraîner des explosions successives

The domino effect and integrated probabilistic approaches for risk analysis

International audienceThe paper develops a probabilistic approach in order to deal with domino effects that may occur in industrial facilities : an explosion or accident may generate various sets of projectiles that may impact other existing facilities (tanks under high-pressure, etc) and may generate other sets of projectiles and so on. Three main parts are considered : 1- Source term : for the first set of generated projectiles, probabilistic distributions are considered for the number, masses, velocities, departure angles, geometrical form, dimensions, and constitutive materials properties. The authors have collected existing models from the literature. 2- Target term : for the set of impacted targets, probabilistic distributions are considered for the number of impacting projectiles, velocities, incidence angles and energy at impact, constitutive materials properties, dimensions of the impacted targets, and projectiles penetration depths into the targets. In this paper, new models for the impact are proposed to calculate the penetration depth after impact : case of cylindrical rods impacting rectangular plates, both are metal made. The theoretical results are compared to the experimental data (4 data sets) collected from the literature with the following features : projectiles mass ranging from 0.1g up to 250 kg, projectiles velocity ranging from 10 m/s up to 2100 m/s, projectiles diameters ranging from 1.5 mm up to 90 mm, target strength ranging from 300 MPa up to 1400 MPa and incidence angles ranging from 0 degree up to 70 degrees. 3- Domino effect term : evaluation of the risks of second set of explosions that may take place in the impacted components. Monte Carlo simulations are used in order to calculate the different probabilities : probability of impact, distribution of the penetration depth and probability of domino effect