539 research outputs found

    A weighted multidimensional index of child well-being which incorporates children’s individual perceptions

    Get PDF
    It has been a decade since a landmark piece of work on child well-being measurement based on a summary index was developed in the United States, the Index of Child and Youth Well-Being. Several research studies, both in the U.S. and Europe, followed on from this work. However, improvements in the methodologies used by researchers are still required, namely with regard to incorporating children’s own perspectives of their well-being, as well as involving them in the measurement process. In the present paper, a composite index is proposed in order to try overcoming three of the main methodological limitations of current studies: the short account for children’s perceptions on their own well-being, the use of aggregated data, and the use of uniform and other weighting schemes that do not translate the real weights of individual indicators.child well-being, measurement, child indicators, methods

    Hexane isomers sorption on the rigid framework MOF MIL-100(Cr)

    Get PDF
    In this work we studied the hexane isomers sorption on the MIL-100(Cr) [1]. The first part of the study was related to the pattern MIL-100(Cr) solid, the second dealt with the MIL-100(Cr) grafted with EtAp (Ethylamine pure) and the third with MIL-100(Cr)MEDA (Methyl ethylene diamine). The synthesis and characterization of MIL-100 (Cr), MIL-100(Cr)EtAp and MIL-100(Cr)MEDA was performed at Institut Lavoisier de Versailles. The separation and adsorption capacity of each MOF were evaluated through breakthrough experiments in a chromatographic system at LSRE using an equimolar mixture of four hexane isomers: n-hexane (nHEX) (RON 25), 3-methylpentane (3MP) (RON 75), 2,3-dimethylbutane (23DMB) (RON 103) and 2,2-dimethylbutane (22DMB) (RON 94) with the objective to the develop an adsorptive process to separate hexane isomers (kinetic diameter very similar) in order to improve the quality of gasoline measured by the octane number (RON)

    Separation of hexane isomers in metal-organic frameworks

    Get PDF
    In this work we study the effect of the functionalization of UiO-66(Zr) architecture with three different organic ligands: 2-aminoterephthalic acid (NH2-H2BDC), 2-nitroterephthalic acid (NO2-H2BDC) and 2-bromoterephthalic acid (Br-H2BDC) on the separation of hexane isomers by adsorption viewing the upgrading of TIP processes. The functionalized MOFs were synthesized and fully characterized applying established techniques: X-ray powder diffraction (XRPD), Infra-Red spectroscopy (IR), Thermo Gravimetric analysis (TGA) and nitrogen adsorption measurement. The potential of separation of the hexane isomers in the synthesized MOFs has been assessed by ISBN: 988-84-695-3536-3 T12-7 performing several screening studies in a breakthrough apparatus exploiting the effect of temperature and partial pressure, demonstrating that functionalization changes sorption behavior improving the separation between 22DMB and the other isomers. Figure 2 shows an experimental breakthrough curve performed in a bed packed with amino functionalized UiO-66 (UiO-66_NH2) where it can be seen that this material is able to separate high RON di-branched isomers (22DMB) from the low RON parents mono (3MP) and linear (nHEX) ones

    Bennettitales, Erdtmanithecales and Gnetales from the Early Cretaceous of the Lusitanian Basin (western Portugal)

    Get PDF
    This paper presents a synthesis of the occurrence of extinct gymnosperms related to the Bennettitales, Erdtmanithecales and Gnetales group and discusses the stratigraphic setting of previously described specimens. These plants are represented by small fossil seeds collected from Lower Cretaceous (Berriasian to Lower Albian) fluvial siliciclastic deposits of the Lusitanian Basin, western Portugal, and probably constitute a monophyletic group, the BEG complex. The fossil seeds are composed of an innermost membranous nucellus preserved as a delicate cuticle. The nucellus is evolved by a membranous integument surrounded by a sclerenchymatic outer envelope. Plants from the BEG complex were contemporary of the earliest angiosperm having shared ecosystems with similar environmental characteristics, what reinforces its paleoecological importance

    Impact of the L-arginine-Nitric Oxide Pathway and Oxidative Stress on the Pathogenesis of the Metabolic Syndrome

    Get PDF
    The discovery of the physiological roles of nitric oxide has revolutionized the understanding of regulation of vascular tone, platelet adhesion and aggregation, and immune activation. Perhaps the most intriguing aspect of nitric oxide (NO) is that it is a gas that, in the absence of receptors, can regulate both normal physiological events and mediate cytotoxicity under pathological conditions. NO is produced from L-arginine by NO synthases (NOS), yielding L-citrulline and NO. The regulation of L-arginine pathway activity occurs at the level of NO production. The metabolic syndrome is a cluster of insulin resistance, elevated blood pressure, and atherogenic dyslipidemia, a common basis of cardiovascular disease. It occurs in genetically susceptible individuals with environmental influences and has serious economic and social consequences. Pharmacological and non-pharmacological therapies should be individualized and targeted to normalize its alterations of blood pressure, HDL cholesterol, triglycerides and glucose values. Despite the increasing prevalence of the metabolic syndrome in the last decades, there has been little progress in the understanding of the precise mechanisms involved in the pathogenesis of this syndrome and its complications. Emerging evidence is available that NO, inflammation and oxidative stress play important roles in the physiopathology of this syndrome. This review summarizes and evaluates the participation of the L-arginine-NO pathway and oxidative stress in the physiopathology of the metabolic syndrome and cardiovascular events at the systemic level, as well as the effects of exercise on this syndrome

    Disease processes identified in road killed wild carnivores

    Get PDF
    Só está disponível o resumoDisease processes identified in road killed wild carnivores
    corecore