No abstract

A coordinated effort to measure divertor heat flux characteristics in fully attached, similarly shaped H-mode plasmas on C-Mod, DIII-D and NSTX was carried out in 2010 in order to construct a predictive scaling relation applicable to next step devices including ITER, FNSF, and DEMO. Few published scaling laws are available and those that have been published were obtained under widely varying conditions and divertor geometries, leading to conflicting predictions for this critically important quantity. This study was designed to overcome these deficiencies. Corresponding plasma parameters were systematically varied in each tokamak, resulting in a combined data set in which I p varies by a factor 3, B t varies by a factor of 14.5, and major radius varies by a factor of 2.6. The derived scaling relation consistently predicts narrower heat flux widths than relations currently in use. Analysis of the combined data set reveals that the primary dependence of the parallel heat flux width is robustly inverse with I p. All three tokamaks independently demonstrate this dependence. The midplane SOL profiles in DIII-D are also found to steepen with higher I p , similar to the divertor heat flux profiles. Weaker dependencies on the toroidal field and normalized Greenwald density, f GW , are also found, but vary across devices and with the measure of the heat flux width used, either FWHM or integral width. In the combined data set, the strongest size scaling is with minor radius resulting in an approximately linear dependence on a/I p. This suggests a scaling correlated with the inverse of the poloidal field, as would be expected for critical gradient or drift-based transport.

No abstract

The control of genotoxic impurities (GTIs) is a crucial activity that is performed for any new chemical entity intended for clinical use. A key element of this is the quality risk assessment. This article seeks to examine the primary components of such a strategy, focusing specifically on the effective use of in silico assessment tools to augment this process, in particular the calculation of theoretical purge factors based on the physicochemical properties of a specific GTI and its interrelationship to the process.

There is a significant need for research and development into paediatric medicines. Only a small fraction of the drugs marketed and utilized as therapeutic agents in children have been clinically evaluated. The majority of marketed drugs are either not labelled, or inadequately labelled, for use in paediatric patients. The absence of suitable medicines or critical safety and efficacy information poses significant risks to a particularly vulnerable patient population. However, there are many challenges associated with developing medicines for the paediatric population and this review paper is intended to highlight these. The paediatric population is made up of a wide range of individuals of substantially varied physical size, weight and stage of physiological development. Experimentation on children is considered by many to be unethical, resulting in difficulties in obtaining critical safety data. Clinical trials are subject to detailed scrutiny by the various regulatory bodies who have recently recognized the need for pharmaceutical companies to invest in paediatric medicines. The costs associated with paediatric product development could result in poor or negative return on investment and so incentives have been proposed by the EU and US regulatory bodies. Additionally, some commonly used excipients may be unsuitable for use in children; and some dosage forms may be undesirable to the paediatric population.