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The article presents a placebo-controlled trial which investigated whether rectal artesunate reduced mortality and permanent disability when given before referral to people with malaria. Patients in Bangladesh, Ghana, and Tanzania with malaria who could not be treated orally were randomly assigned to either single artesunate or placebo suppository. They were subsequently referred to clinics for injections. Researchers found that the artesunate suppository substantially reduced the risk of death or permanent disability among patients with severe malaria who could not be treated orally and had delayed access to injections.

New data on the aqueous solubility of n-octane, 1-chlorooctane and 1-bromooctane are reported between 1°C and 45°C. Henry’s law constants, KH, and air/water partition coefficients, KAW, were calculated by associating the measured solubility values to vapor pressures taken from literature. The mole fraction aqueous solubility varies between (1.13–1.60)×10−7 for n-octane with a minimum at approximately 23°C, (3.99–5.07)×10−7 for 1-chlorooctane increasing monotonically with temperature and (1.60–3.44)×10−7 for 1-bromooctane with a minimum near 18°C. The calculated air–water partition coefficients increase with temperature and are two orders of magnitude lower for the halogenated derivatives compared to octane. The precision of the results, taken as the average absolute deviations of the aqueous solubility, the Henry’s law constants, or the air/water partition coefficients, from appropriate smoothing equations as a function of temperature is of 3% for n-octane and of 2% and 4% for 1-chlorooctane and 1-bromooctane, respectively. A new apparatus based on the dynamic saturation column method was used for the solubility measurements. Test measurements with n-octane indicated the capability of measuring solubilities between 10−6 and 10−10 in mole fraction, with an estimated accuracy better than ±10%. A thorough thermodynamic analysis of converting measured data to air/water partition coefficients is presented. [Copyright &y& Elsevier]

Abstract: We present a study on the effect of the alkyl chain length of the imidazolium ring in 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquids, [C1C n Im][NTf2] (n =2 to 10), on the mixing properties of (ionic liquid+alcohol) mixtures (enthalpy and volume). We have measured small excess molar volumes with highly asymmetric curves as a function of mole fraction composition (S-shape) with more negative values in the alcohol-rich regions. The excess molar volumes increase with the increase of the alkyl-chain length of the imidazolium cation of the ionic liquid. The values of the partial molar excess enthalpy and the enthalpy of mixing are positive and, for the case of methanol, do not vary monotonously with the length of the alkyl side-chain of the cation on the ionic liquid – increasing from n =2 to 6 and then decreasing from n =8. This non-monotonous variation is explained by a more favourable interaction of methanol with the cation head group of the ionic liquid for alkyl chains longer than eight carbon atoms. It is also observed that the mixing is less favourable for the smaller alcohols, the enthalpy of mixing decreasing to less positive values as the alkyl chain of the alcohol increases. Based on the data from this work and on the knowledge of the vapour pressure of {[C1C n Im][NTf2]+alcohol} binary mixtures at T =298K reported in the literature, the excess Gibbs free energy, excess enthalpy and excess entropy could be then calculated and it was observed that these mixtures behave like the ones constituted by a non-associating and a non-polar component, with its solution behaviour being determined by the enthalpy. [Copyright &y& Elsevier]