732 research outputs found

    Flight test results for a separate surface stability augmented Beech model 99

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    A flight evaluation of a Beech model 99 equipped with an attitude command control system incorporating separate surface stability augmentation (SSSA) was conducted to determine whether an attitude command control system could be implemented using separate surface controls, and to determine whether the handling and ride qualities of the aircraft were improved by the SSSA attitude command system. The results of the program revealed that SSSA is a viable approach to implementing attitude command and also that SSSA has the capability of performing less demanding augmentation tasks such as yaw damping, wing leveling, and pitch damping. The program also revealed that attitude command did improve the pilot rating and ride qualities of the airplane while flying an IFR mission in turbulence. Some disadvantages of the system included the necessity of holding aileron force in a banked turn and excessive stiffness in the pitch axis

    NASA tungsten reactor radiation chemistry studies Final report

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    Cadmium sulfate poison control solutions for tungsten water moderated reacto

    How to humiliate and shame: A reporter's guide to the power of the mugshot

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    This is an Author's Accepted Manuscript of an article published in Social Semiotics, 24(1), 56-87, 2014, copyright Taylor & Francis, available online at: http://www.tandfonline.com/The judicial photograph – the “mugshot” – is a ubiquitous and instantly recognisable form, appearing in the news media, on the internet, on book covers, law enforcement noticeboards and in many other mediums. This essay attempts to situate the mugshot in a historical and theoretical context to explain the explicit and implicit meaning of the genre as it has developed, focussing in particular on their use in the UK media in late modernity. The analysis is based on the author's reflexive practice as a journalist covering crime in the national news media for 30 years and who has used mugshots to illustrate stories for their explicit and specific content. The author argues that the visual limitations of the standardised “head and shoulders” format of the mugshot make it a robust subject for analysing the changing meaning of images over time. With little variation in the image format, arguments for certain accreted layers of signification are easier to make. Within a few years of the first appearance of the mugshot form in the mid-19th century, it was adopted and adapted as a research tool by scientists and criminologists. While the positivist scientists claimed empirical objectivity we can now see that mugshots played a part in the construction of subjective notions of “the other”, “the lesser” or “sub-human” on the grounds of class, race and religion. These dehumanising ideas later informed the theorists and bureaucrats of National Socialist ideology from the 1920s to 1940s. The author concludes that once again the mugshot has become, in certain parts of the media, a signifier widely used to exclude or deride certain groups. In late modernity, the part of the media that most use mugshots – the tabloid press and increasingly tabloid TV – is part of a neo-liberal process that, in a conscious commercial appeal to the paying audience, seeks to separate rather than unify wider society

    Who are these youths? Language in the service of policy

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    In the 1990s policy relating to children and young people who offend developed as a result of the interplay of political imperatives and populist demands. The ‘responsibilisation’ of young offenders and the ‘no excuses’ culture of youth justice have been ‘marketed’ through a discourse which evidences linguistic changes. This article focuses on one particular area of policy change, that relating to the prosecutorial decision, to show how particular images of children were both reflected and constructed through a changing selection of words to describe the non-adult suspect and offender. In such minutiae of discourse can be found not only the signifiers of public attitudinal and policy change but also the means by which undesirable policy developments can be challenged

    Anti-Nirvana: crime, culture and instrumentalism in the age of insecurity

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    ‘Anti-Nirvana’ explores the relationship between consumer culture, media and criminal motivations. It has appeared consistently on the list of the top-ten most-read articles in this award-winning international journal, and it mounts a serious neo-Freudian challenge to the predominant naturalistic notion of ‘resistance’ at the heart of liberal criminology and media studies. It is also cited in the Oxford Handbook of Criminology and other criminology texts as a persuasive argument in support of the theory that criminality amongst young people is strongly linked to the acquisitive values of consumerism and the images of possessive individualism that dominate mass media

    The Image of the City Out of the Underlying Scaling of City Artifacts or Locations

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    Two fundamental issues surrounding research on the image of the city respectively focus on the city's external and internal representations. The external representation in the context of this paper refers to the city itself, external to human minds, while the internal representation concerns how the city is represented in human minds internally. This paper deals with the first issue, i.e., what trait the city has that make it imageable? We develop an argument that the image of the city arises from the underlying scaling of city artifacts or locations. This scaling refers to the fact that, in an imageable city (a city that can easily be imaged in human minds), small city artifacts are far more common than large ones; or alternatively low dense locations are far more common than high dense locations. The sizes of city artifacts in a rank-size plot exhibit a heavy tailed distribution consisting of the head, which is composed of a minority of unique artifacts (vital and very important), and the tail, which is composed of redundant other artifacts (trivial and less important). Eventually, those extremely unique and vital artifacts in the top head, i.e., what Lynch called city elements, make up the image of the city. We argue that the ever-increasing amount of geographic information on cities, in particular obtained from social media such as Flickr and Twitter, can turn research on the image of the city, or cognitive mapping in general, into a quantitative manner. The scaling property might be formulated as a law of geography. Keywords: Scaling of geographic space, face of the city, cognitive maps, power law, and heavy tailed distributions.Comment: 13 pages, 9 figures, 2 table

    Adaptive evolution of drug targets in producer and non-producer organisms

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    Mycophenolic acid (MPA) is an immunosuppressive drug produced by several fungi in Penicillium subgenus Penicillium. This toxic metabolite is an inhibitor of IMP dehydrogenase (IMPDH). The MPA biosynthetic cluster of P. brevicompactum contains a gene encoding a B-type IMPDH, IMPDH-B, which confers MPA-resistance. Surprisingly, all members of subgenus Penicillium contain genes encoding IMPDHs of both the A and B type, regardless of their ability to produce MPA. Duplication of the IMPDH gene occurred prior to and independent of the acquisition of the MPA biosynthetic cluster. Both P. brevicompactum IMPDHs are MPA-resistant while the IMPDHs from a nonproducer are MPA-sensitive. Resistance comes with a catalytic cost: while P. brevicompactum IMPDH-B is >1000-fold more resistant to MPA than a typical eukaryotic IMPDH, its value of k(cat)/K(m) is 0.5% of “normal”. Curiously, IMPDH-B of Penicillium chrysogenum, which does not produce MPA, is also a very poor enzyme. The MPA binding site is completely conserved among sensitive and resistant IMPDHs. Mutational analysis shows that the C-terminal segment is a major structural determinant of resistance. These observations suggest that the duplication of the IMPDH gene in Pencillium subgenus Penicillium was permissive for MPA production and that MPA production created a selective pressure on IMPDH evolution. Perhaps MPA production rescued IMPDH-B from deleterious genetic drift

    Limited Urban Growth: London's Street Network Dynamics since the 18th Century

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    We investigate the growth dynamics of Greater London defined by the administrative boundary of the Greater London Authority, based on the evolution of its street network during the last two centuries. This is done by employing a unique dataset, consisting of the planar graph representation of nine time slices of Greater London's road network spanning 224 years, from 1786 to 2010. Within this time-frame, we address the concept of the metropolitan area or city in physical terms, in that urban evolution reveals observable transitions in the distribution of relevant geometrical properties. Given that London has a hard boundary enforced by its long-standing green belt, we show that its street network dynamics can be described as a fractal space-filling phenomena up to a capacitated limit, whence its growth can be predicted with a striking level of accuracy. This observation is confirmed by the analytical calculation of key topological properties of the planar graph, such as the topological growth of the network and its average connectivity. This study thus represents an example of a strong violation of Gibrat's law. In particular, we are able to show analytically how London evolves from a more loop-like structure, typical of planned cities, toward a more tree-like structure, typical of self-organized cities. These observations are relevant to the discourse on sustainable urban planning with respect to the control of urban sprawl in many large cities, which have developed under the conditions of spatial constraints imposed by green belts and hard urban boundaries.Comment: PlosOne, in publicatio
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