67 research outputs found

    Controlling unstable chaos: stabilizing chimera states by feedback

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    Copyright © 2014 American Physical SocietyWe present a control scheme that is able to find and stabilize an unstable chaotic regime in a system with a large number of interacting particles. This allows us to track a high dimensional chaotic attractor through a bifurcation where it loses its attractivity. Similar to classical delayed feedback control, the scheme is noninvasive, however only in an appropriately relaxed sense considering the chaotic regime as a statistical equilibrium displaying random fluctuations as a finite size effect. We demonstrate the control scheme for so-called chimera states, which are coherence-incoherence patterns in coupled oscillator systems. The control makes chimera states observable close to coherence, for small numbers of oscillators, and for random initial conditions.Engineering and Physical Sciences Research Council (EPSRC

    Phase sensitive excitability of a limit cycle

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    The classical notion of excitability refers to an equilibrium state that shows under the influence of perturbations a nonlinear threshold-like behavior. Here, we extend this concept by demonstrating how periodic orbits can exhibit a specific form of excitable behavior where the nonlinear threshold-like response appears only after perturbations applied within a certain part of the periodic orbit, i.e the excitability happens to be phase sensitive. As a paradigmatic example of this concept we employ the classical FitzHugh-Nagumo system. The relaxation oscillations, appearing in the oscillatory regime of this system, turn out to exhibit a phase sensitive nonlinear threshold-like response to perturbations, which can be explained by the nonlinear behavior in the vicinity of the canard trajectory. Triggering the phase sensitive excitability of the relaxation oscillations by noise we find a characteristic non-monotone dependence of the mean spiking rate of the relaxation oscillation on the noise level. We explain this non-monotone dependence as a result of an interplay of two competing effects of the increasing noise: the growing efficiency of the excitation and the degradation of the nonlinear response

    Nebuliser therapy in the intensive care unit

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    The relationship between identity, lived experience, sexual practices and the language through which these are conveyed has been widely debated in sexuality literature. For example, ‘coming out’ has famously been conceptualised as a ‘speech act’ (Sedgwick 1990) and as a collective narrative (Plummer 1995), while a growing concern for individuals’ diverse identifications in relations to their sexual and gender practices has produced interesting research focusing on linguistic practices among LGBT-identified individuals (Leap 1995; Kulick 2000; Cameron and Kulick 2006; Farqhar 2000). While an explicit focus on language remains marginal to literature on sexualities (Kulick 2000), issue of language use and translation are seldom explicitly addressed in the growing literature on intersectionality. Yet intersectional perspectives ‘reject the separability of analytical and identity categories’ (McCall 2005:1771), and therefore have an implicit stake in the ‘vernacular’ language of the researched, in the ‘scientific’ language of the researcher and in the relationship of continuity between the two. Drawing on literature within gay and lesbian/queer studies and cross-cultural studies, this chapter revisits debates on sexuality, language and intersectionality. I argue for the importance of giving careful consideration to the language we choose to use as researchers to collectively define the people whose experiences we try to capture. I also propose that language itself can be investigated as a productive way to foreground how individual and collective identifications are discursively constructed, and to unpack the diversity of lived experience. I address intersectional complexity as a methodological issue, where methodology is understood not only as the methods and practicalities of doing research, but more broadly as ‘a coherent set of ideas about the philosophy, methods and data that underlie the research process and the production of knowledge’ (McCall 2005:1774). My points are illustrated with examples drawn from my ethnographic study on ‘lesbian’ identity in urban Russia, interspersed with insights from existing literature. In particular, I aim to show that an explicit focus on language can be a productive way to explore the intersections between the global, the national and the local in cross-cultural research on sexuality, while also addressing issues of positionality and accountability to the communities researched

    From Barbie to the oligarchs wife: Reading fantasy femininity and globalisation in post-Soviet Russian womens magazines

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    This article shows how an analysis of fantasy femininity sheds light on how norms of gender, class and national identity reflect global and local cross-cultural currents in post-Soviet Russia. Drawing on a discourse analysis of women’s magazines and in-depth interviews with readers, it shows how, in the globalized post-Soviet cultural landscape, fantasy femininity represents both change and continuity. Feminine archetypes in women’s magazines, from fairytale princesses to Barbie dolls, reflect a wider post-Soviet cultural hybridisation, and show how Western women’s magazines have adapted to the Russian context. Furthermore, the article highlights readers’ ambiguous attitudes towards post-Soviet cultural trends linked to perceived Westernisation or globalisation, such as individualism, conspicuous consumption, and glamour

    To love, be proud, leave? Russian youth in a patriotic labyrinth

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    Russia's Skinheads: Exploring and Rethinking Subcultural Lives

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    Russia’s Skinheads: Exploring and Rethinking Subcultural Lives provides a thorough examination of the phenomenon of skinheads, explaining its nature and its significance, and assessing how far Russian skinhead subculture is the ‘lumpen’ end of the extreme nationalist ideological spectrum. There are large numbers of skinheads in Russia, responsible for a significant number of xenophobic attacks, including 97 deaths in 2008 alone, making this book relevant to Russian specialists as well as to sociologists of youth subculture. It provides a practical example of how to investigate youth subculture in depth over an extended period – in this case through empirical research following a specific group over six years – and goes on to argue that Russian skinhead subculture is not a direct import from the West, and that youth cultural practices should not be reduced to expressions of consumer choice. It presents an understanding of the Russian skinhead as a product of individuals’ whole, and evolving, lives, and thereby compels sociologists to rethink how they conceive the nature of subcultures
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