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The fast evolution of transmission systems, induced by the massive integration of high voltage direct current links, special protection schemes and renewable energies, has a strong influence on the system's behaviour and the steady state it reaches after one or several events. The power flow tools that are currently used to calculate steady states after some events are not adapted any more to such changes. A case study advocating for the use of simplified time-domain simulations for steady state calculation instead of fully static tools is presented here. This case study is simulated using DynaFlow, a new simulation tool that does a simplified time-domain simulation whose final state is given as a result. It focuses on the France–Spain border, and it is shown that the dynamic parameters of the special protection schemes have a strong impact on the steady state that cannot be easily captured by classical power flow tools. A sensitivity analysis is also done to illustrate this. • The advantage of using a simplified time-domain approach is presented on a real case. • Simulations focus on the French grid system, around the France–Spain border. • Taking into account temporality of controls allows to catch their mutual influence. • Modifying the HVDC links response time has an impact on the final position of PSTs taps. • Larger margins of power export are observed when introducing controls temporality. [ABSTRACT FROM AUTHOR]

The article presents an experimental study on the development of bedforms in the supply limited configuration in France. The study highlights the role played by the sediment supply rate and the shear velocity in the development of the bedform. The findings of the study will be used to control the equilibrium height and migration speed of bedforms in supply-limited conditions.

Aims: Methadone is characterized by wide intersubject variability regarding the dose needed to obtain full therapeutic response. We assessed the influence of sociodemographic, ethnic, clinical, metabolic and genotypic variables on methadone maintenance dose requirement in opioid-dependent responder patients., Methods: Eighty-one stable patients (60 men and 21 women, 43.7 ± 8.1 years old, 63.1 ± 50.9 mg day(-1) methadone), divided into quartiles with respect to the median daily dose, were enrolled and underwent clinical examination, treatment history and determination of liver/intestinal cytochrome P450 (CYP) 3A4 activity measured by the midazolam test, R,S-methadone trough concentration and clinically significant polymorphisms of the OPRM1, DRD2, COMT, ABCB1, CYP2B6, CYP3A5, CYP2C19 and CYP2D6 genes., Results: Methadone maintenance dose was correlated to the highest dose ever used (r(2) = 0.57, P < 0.0001). Fractioned methadone intake (odds ratio 4.87, 95% confidence interval 1.27-18.6, P = 0.02), bodyweight (odds ratio 1.57, 95% confidence interval 1.01-2.44, P = 0.04), history of cocaine dependence (80 vs. 44 mg day(-1) in never-addict patients, P = 0.005) and ethnicity (Asian > Caucasian > African, P = 0.04) were independently associated with high-dose methadone in multiple regression analysis. A modest correlation was observed between liver/intestinal CYP3A4 activity and methadone dose at steady state (Spearman rank correlation coefficient [rs ] = 0.21, P = 0.06) but not with highest dose ever used (rs = 0.15, P = 0.18) or dose-normalized R,S-methadone trough concentrations (rs = -0.05, P = 0.64). Concomitant CYP3A4 inhibitors only affected the relationship between methadone dose and R,S-methadone trough concentration. None of the genetic polymorphisms explored was predictive of the methadone maintenance dose., Conclusions: Methadone maintenance dose was predicted by sociodemographic and clinical variables rather than genetic polymorphisms or liver/intestinal CYP3A4 activity in stable patients., (© 2015 The British Pharmacological Society.)