105 research outputs found

    Impact of tunable oligophosphonates on barium sulfate crystallization

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    Calixarenes can be used as well-defined scaffolds for investigating structure–activity relationships of additives and their impact on crystallization. In this work, we present the crystal growth modification of barium sulfate by p-phosphonic acid calix[n]arenes that vary in size (n = 4, 5, 6, and 8) and thus vary in the size of the internal cavity for the same functionality in the upper rim. The tetrameric, hexameric, and octameric macrocycles induce nanoparticle formation with clear superstructure. In the case of the hexameric calix[6]arene, the initial mesocrystalline superstructure fuses over time to form almost hollow spheres, while the mesocrystals formed in the presence of the tetramer and octamer are stable over an extended period. The pentameric calix[5]arene forms more disordered aggregates of single crystals. Thermogravimetric data shows that a significant proportion of the mass of the barium sulfate-containing solid is the macrocycle, regardless of the choice of macrocycle

    Framing the Paralympic Games: A Mixed-Methods Analysis of Spanish Media Coverage of the Beijing 2008 and London 2012 Paralympic Games

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    In recent years, there has been an increased emergence of studies focusing on the media coverage of the Paralympic Games. Until recently, studies have predominately used quantitative content analyses that, although providing useful interrogation of observational patterns, limits the understanding of and appreciation for the contexts that may have shaped the production of information. By focusing exclusively on the ‘what’ and on the ‘how much’ it is difficult to reveal the ‘why’ and to identify the underlying motives of any changes. This paper recognizes the nuances of the editorial decision-making process by using a mixed methods approach; employing quantitative and qualitative data drawn from a case study focusing on the Spanish media coverage of the 2008 and 2012 Paralympic Games. An initial content analysis of all news published in Spain’s twelve highest-circulation newspapers during Beijing 2008 and London 2012 Paralympic Games was undertaken. Subsequently, 15 semi-structured interviews were conducted with journalists that were also sent to these two iterations of the Paralympic Games by Spanish media. Drawing on conceptualisations of media framing, the results highlight that the numerical data alone shed insufficient light on the complexity of the news-making process. The semi-structured interviews brought to light issues such as editorial management buoyed by commercial imperatives, and organisational interjection in journalists’ narratives and authorship, that also contoured coverage and content. In addition to further debate about the complexities of media coverage of Paralympic sport, the study also underscores the utility of incorporating and combining qualitative and quantitative methodologies within sport media and communication research

    From old organisms to new molecules: integrative biology and therapeutic targets in accelerated human ageing

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    Understanding the basic biology of human ageing is a key milestone in attempting to ameliorate the deleterious consequences of old age. This is an urgent research priority given the global demographic shift towards an ageing population. Although some molecular pathways that have been proposed to contribute to ageing have been discovered using classical biochemistry and genetics, the complex, polygenic and stochastic nature of ageing is such that the process as a whole is not immediately amenable to biochemical analysis. Thus, attempts have been made to elucidate the causes of monogenic progeroid disorders that recapitulate some, if not all, features of normal ageing in the hope that this may contribute to our understanding of normal human ageing. Two canonical progeroid disorders are Werner’s syndrome and Hutchinson-Gilford progeroid syndrome (also known as progeria). Because such disorders are essentially phenocopies of ageing, rather than ageing itself, advances made in understanding their pathogenesis must always be contextualised within theories proposed to help explain how the normal process operates. One such possible ageing mechanism is described by the cell senescence hypothesis of ageing. Here, we discuss this hypothesis and demonstrate that it provides a plausible explanation for many of the ageing phenotypes seen in Werner’s syndrome and Hutchinson-Gilford progeriod syndrome. The recent exciting advances made in potential therapies for these two syndromes are also reviewed
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