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Mode of access: Internet.
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In this study, the partial molar volumes of L-serine and L-threonine in aqueous solutions of ammonium sulfate at (0.0, 0.1, 0.3, 0.7, and 1.0) mol.kg(-1) are reported between 278.15 and 308.15 K. Transfer volumes and hydration numbers were obtained, which are larger in L-serine than in L-threonine. Dehydration of the amino acids is observed, rising with the temperature and salt molality. The data suggest that interactions between ions and charged/hydrophilic groups are predominant, and by applying the McMillan and Mayer formalism, it was concluded that they are mainly pair wise. The combination of the data presented in this study with solubility and molecular dynamics data suggests a stronger interaction of the ammonium cation with the zwitterionic centers of the amino acids when compared to the interactions of those centers with the sulfate anion.
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In this work, the partial molar volumes of glycine and DL-alanine in aqueous solutions of ammonium sulfate at 0.0, 0.1, 0.3, 0.7, and 1.0 mol.kg(-1) are determined between 278.15 and 308.15 K. Transfer volumes were obtained, which are larger for glycine than DL-alanine. On the contrary, the hydration numbers are higher for DL-alanine than glycine, and dehydration of the amino acids is observed with increasing temperature or salt molality. The data suggest that interactions between ion and charged/hydrophilic groups are predominant and, by applying the methodology proposed by Friedman and Krishnan, it was concluded that they are mainly pairwise. A group-contribution scheme has been successfully applied to the pairwise volumetric interaction coefficient. Finally, the dehydration effect on glycine, alanine and serine in the presence of different electrolytes has been rationalized in terms of the charge density and a parameter accounting for the cation's hydration.
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In this work, the partial molar volumes of glycine, l-alanine, l-valine, l-serine, and l-threonine in aqueous solutions of magnesium chloride at 0.0, 0.1, 0.3, 0.7, and 1.0 molal are addressed between 278.15 and 308.15 K. Volumes of transfer were obtained, following the rank serine > glycine a parts per thousand threonine > alanine > valine. Differently, the hydration numbers follow the sequence serine > valine > alanine > threonine > glycine, and dehydration of the amino acids is observed, rising the temperature or salt molality. The data suggest that interactions are mainly pairwise, between the ions and charged/hydrophilic groups of the amino acids. Within the Friedman and Krishnan formalism, a group-contribution scheme has been successfully applied to the pairwise volumetric interaction coefficient. Finally, the dehydration effect of MgCl2 on glycine, alanine, and serine has been predicted applying empirical correlations developed before, showing satisfactory results.
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Rezension von: Manfred Liebel: Kinder und Gerechtigkeit. Über Kinderrechte neu nachdenken. Weinheim / Basel: Beltz Juventa 2013 (278 S.; ISBN 978-3-7799-2837-9)
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Objective: To assess the health-related quality of life (HRQoL) in children 1-2 years after they had sustained an injury. Methods: Parents of all children who were identified by the Queensland Trauma Registry during their admission to either of the two paediatric specialty hospitals in Brisbane, Australia, for the treatment of an injury, were invited to participate in this study. Parents who consented to participation received a copy of the Child Health Questionnaire (CHQ) that required them to provide information regarding their child’s HRQoL following injury. The CHQ scores for the study respondents were compared with those of the Australian norms. This study was approved by the relevant ethics committees. Results: Two hundred and forty-one completed questionnaires were returned. The majority of cases were male (65%) and there was even representation across all age groups. The majority of injuries were considered to be minor (81%) and were predominantly the result of falls and cycling accidents causing mainly fractures and intracranial injury. On the majority of subscales of the CHQ, study participants recorded scores that were statistically significantly below those of the Australian norms. None of the relevant variables collected by the Queensland Trauma Registry were found to predict scores on the CHQ in this study (for those children hospitalized for >24 h). Conclusion: Injured children are worse off than their Australian counterparts in terms of HRQoL even up to 2 years following an injury. Further research needs to be undertaken to identify factors that predict lower HRQoL in order to reduce the burden of injury on children and their families.
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The portability and runtime safety of programs which are executed on the Java Virtual Machine (JVM) makes the JVM an attractive target for compilers of languages other than Java. Unfortunately, the JVM was designed with language Java in mind, and lacks many of the primitives required for a straighforward implementation of other languages. Here, we discuss how the JVM may be used to implement other object-oriented languages. As a practical example of the possibilities, we report on a comprehensive case study. The open source Gardens Point Component Pascal compiler compiles the entire Component Pascal language, a dialect of Oberon-2, to JVM bytecodes. This compiler achieves runtime efficiencies which are comparable to native-code implementations of procedural languages.