25 resultados para Classificació AMS::01 History and biography::01A History of mathematics and mathematicians

em CentAUR: Central Archive University of Reading - UK


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Changes in atmospheric temperature have a particular importance in climate research because climate models consistently predict a distinctive vertical profile of trends. With increasing greenhouse gas concentrations, the surface and troposphere are consistently projected to warm, with an enhancement of that warming in the tropical upper troposphere. Hence, attempts to detect this distinct ‘fingerprint’ have been a focus for observational studies. The topic acquired heightened importance following the 1990 publication of an analysis of satellite data which challenged the reality of the projected tropospheric warming. This review documents the evolution over the last four decades of understanding of tropospheric temperature trends and their likely causes. Particular focus is given to the difficulty of producing homogenized datasets, with which to derive trends, from both radiosonde and satellite observing systems, because of the many systematic changes over time. The value of multiple independent analyses is demonstrated. Paralleling developments in observational datasets, increased computer power and improved understanding of climate forcing mechanisms have led to refined estimates of temperature trends from a wide range of climate models and a better understanding of internal variability. It is concluded that there is no reasonable evidence of a fundamental disagreement between tropospheric temperature trends from models and observations when uncertainties in both are treated comprehensively

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Aromatic amino acid hydroxylase (AAAH) genes and insulin-like genes form part of an extensive paralogy region shared by human chromosomes 11 and 12, thought to have arisen by tetraploidy in early vertebrate evolution. Cloning of a complementary DNA (cDNA) for an amphioxus (Branchiostoma floridae) hydroxylase gene (AmphiPAH) allowed us to investigate the ancestry of the human chromosome 11/12 paralogy region. Molecular phylogenetic evidence reveals that AmphiPAH is orthologous to vertebrate phenylalanine (PAH) genes; the implication is that all three vertebrate AAAH genes arose early in metazoan evolution, predating vertebrates. In contrast, our phylogenetic analysis of amphioxus and vertebrate insulin-related gene sequences is consistent with duplication of these genes during early chordate ancestry. The conclusion is that two tightly linked gene families on human chromosomes 11 and 12 were not duplicated coincidentally. We rationalize this paradox by invoking gene loss in the AAAH gene family and conclude that paralogous genes shared by paralogous chromosomes need not have identical evolutionary histories.

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This essay traces the development of Otto Neurath’s ideas that led to the publication of one of the first series of children’s books produced by the Isotype Institute in the late 1940s, the Visual History of Mankind. Described in its publicity material as ‘new in content’ and ‘new in method’, it embodied much of Otto Neurath’s thinking about visual education, and also coincided with other educational ideas in the UK in the 1930s and 1940s. It exemplified the Isotype Institute’s approach: teamwork, thinking about the needs of younger readers, clear explanation, and accessible content. Further, drawing on correspondence, notes and drawings from the Otto and Marie Neurath Isotype Collection at the University of Reading, the essay presents insights to the making of the books and the people involved, the costs of production and the influence of this on design decisions, and how the books were received by teachers and children.

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This is a history of fascist Italy from 1919 to 1945 that explores through the private (and mostly unpublished) diaries, letters and memoirs of ordinary people, how the regime was lived and experienced. It sets out to examine the emotional, cultural and ideological landscape of fascism and to investigate what it was that induced so many millions of people to give their support, in varying degrees, to a regime that led the country ultimately to disaster.