1,301 research outputs found
Beyond âMove Moreâ: Feeling the Rhythms of physical activity in mid and later-life
This is the author accepted manuscriptThe last two decades have seen growing unease regarding the negative health consequences of increasing levels of physical inactivity, both in the UK and further afield. Public health initiatives and interventions aimed at increasing levels of physical activity have, therefore, become somewhat commonplace. Within the current context of demographic change, with growing numbers of older adults and evidence that inactivity increases with age, these initiatives hold particular relevance to mid and later-life adults. Yet despite their prevalence, the policy gains from such promotional efforts have typically been modest at best, demonstrating the limits to decontextualized health messages that encourage people to âsit lessâ, âmove moreâ or âmove fasterâ.
In this paper, we draw on the concept of rhythm, to provide an original contribution in response to recent calls to rethink existing approaches to physical activity in mid-life and beyond. We draw from three qualitative data sets from separate studies exploring health, wellbeing and ageing (two in the context of chronic health conditions and sensory impairments). Inspired by facet methodology, we advance knowledge by providing âflashes of insightâ into the subtle patterns and tempos that frame physical activity in mid and later life. In doing so, we offer alternative insight into how people avail themselves to, and experience motion and stillness during these life stages. That alternative, as we also note, has an important role to play in the development of appropriate, relatable health messages regarding movement that recognises âexpertise by experienceâ.This work was supported by funding from the Economic and SocialResearch Council (RES-061-30-000551), the Thomas Pocklington Trustand the MĂ©niĂšre's Society
Polarization and frequency disentanglement of photons via stochastic polarization mode dispersion
We investigate the quantum decoherence of frequency and polarization
variables of photons via polarization mode dispersion in optical fibers. By
observing the analogy between the propagation equation of the field and the
Schr\"odinger equation, we develop a master equation under Markovian
approximation and analytically solve for the field density matrix. We identify
distinct decay behaviors for the polarization and frequency variables for
single-photon and two-photon states. For the single photon case, purity
functions indicate that complete decoherence for each variable is possible only
for infinite fiber length. For entangled two-photon states passing through
separate fibers, entanglement associated with each variable can be completely
destroyed after characteristic finite propagation distances. In particular, we
show that frequency disentanglement is independent of the initial polarization
status. For propagation of two photons in a common fiber, the evolution of a
polarization singlet state is addressed. We show that while complete
polarization disentanglement occurs at a finite propagation distance, frequency
entanglement could survive at any finite distance for gaussian states.Comment: 2 figure
The dissipative dynamics of the field of two-photon Jaynes-Cummings model with Stark shift in dispersive approximation
We present the dissipative dynamics of the field of two-photon
Jaynes-Cummings model (JCM) with Stark shift in dispersive approximation and
investigate the influence of dissipation on entanglement. We show the coherence
properties of the field can be affected by the dissipative cavity when
nonlinear two-photon process is involved.Comment: 8 pages,3 figure
Keeping it in the family: narrative maps of ageing and young athletes' perceptions of their futures
© Cambridge University Press 2006. Published version reproduced with the permission of the publisher.Drawing upon interviews with 22 young athletes aged on average 20 years, this article examines the ways in which they used observations of the ageing and old age of their family members to shape the ways in which they anticipated the ageing of their own bodies. The representations of the bodies, roles and lifestyles of their parents and grandparents provided ânarrative mapsâ that held pre-presentations of the young athletesâ possible futures. They included both preferred and feared scenarios about middle age and old age, particularly the opportunities they would have for maintaining physical activity and the appearance of their bodies. The young menâs and the young womenâs narrative maps differed: the womenâs accounts of old age gave more prominence to the loss of appearance, while the menâs focused more on the loss of control and independence. The informants were highly sensitised to the biological dimensions of ageing which, for them, meant the inevitable decline of the material body, especially in performance terms, and both genders recognised social dimensions, particularly that responsibilities to jobs and family would constrain the time available for exercise. To understand more fully young athletesâ experiences of self-ageing, and the family as a key arena for the embodied projection and inscription of ageing narratives, further research is required
Being Fred: Big stories, small stories and the accomplishment of a positive ageing identity
This is a postprint of an article published in Qualitative Research, Volume 9 (2), 83 - 99. © 2009 copyright SAGE Publications. Qualitative Research is available online at: http://www.uk.sagepub.com/journals.navThis article is informed by recent trends in narrative research that focus on the meaning-making actions of those involved in describing the life course. Drawing upon data generated during a series of interactive interviews with a 70-year-old physically active man named Fred, his story is presented to illustrate a strategic model of narrative activity. In particular, using the concepts of `big stories' and `small stories' as an analytical framework, we trace Fred's use of two specific identities; being fit and healthy , and being leisurely to analyse the ways that he accomplishes an ontological narrative where the plot line reads; `Life is what you make it'. The ways in which this narrative enables Fred to perform a narrative of positive self-ageing in his everyday life is illustrated. Finally, the analytical possibilities of being attentive to both big and small stories in narrative analysis are discussed
Segregation and the Sea: Towards a Critical Understanding of Race and Coastal Blue Space in Greater Miami
This is the final version. Available on open access from SAGE Publications via the DOI in this recordThere is a growing body of research signalling the health and wellbeing benefits of being in
blue space. Here, we advance this intellectual agenda by critically examining perceptions
and experiences of coastal blue space among residents of a disadvantaged, predominantly
African-American community who report limited engagement with their local coastal blue
space, despite beachgoing being considered mainstream by a previous generation. Drawing
on focus group data and sensitised to a range of theoretical perspectives aligned with race,
space and social class, we advance theoretical and empirical knowledge pertaining to blue
space engagement. In doing so, we demonstrate the need for more critically informed,
theoretically appropriate research in this area, which connects individual stories of the sea
to the wider historical, social and political settings in which relationships with blue space are
framed and produced.University of ExeterEuropean Regional Development Fund Programme 2007-2013European Social Fund Convergence Programme for Cornwall and the Isles of ScillyNational Science Foundation (NSF)National Institute of Environmental Health Sciences (NIEHS) Oceans and Human Health Center, University of Miami Rosenstiel Schoo
Spherical Code Key Distribution Protocols for Qubits
Recently spherical codes were introduced as potentially more capable
ensembles for quantum key distribution. Here we develop specific key creation
protocols for the two qubit-based spherical codes, the trine and tetrahedron,
and analyze them in the context of a suitably-tailored intercept/resend attack,
both in standard form, and a ``gentler'' version whose back-action on the
quantum state is weaker. When compared to the standard unbiased basis
protocols, BB84 and six-state, two distinct advantages are found. First, they
offer improved tolerance of eavesdropping, the trine besting its counterpart
BB84 and the tetrahedron the six-state protocol. Second, the key error rate may
be computed from the sift rate of the protocol itself, removing the need to
sacrifice key bits for this purpose. This simplifies the protocol and improves
the overall key rate.Comment: 4 pages revtex, 2 figures; clarified security analysis. Final version
for publicatio
Using geonarratives to explore the diverse temporalities of therapeutic landscapes: perspectives from âgreenâ and âblueâ settings
This is the author accepted manuscript. The final version is available from Taylor and Francis via the DOI in this record.A growing evidence base highlights âgreenâ and âblueâ spaces as examples of
âtherapeutic landscapesâ incorporated into peopleâs lives to maintain a sense of wellbeing. A
commonly overlooked dimension within this corpus of work concerns the dynamic nature of
peopleâs therapeutic place assemblages over time. This article provides these novel temporal
perspectives, drawing on the findings of an innovative three-stage interpretive geo-narrative
study conducted in south-west England from May to November 2013, designed to explore the
complex spatial-temporal ordering of peopleâs lives. Activity maps produced using
accelerometer and Global Positioning system (GPS) data were used to guide in-depth geonarrative
interviews with 33 participants, followed by a subset of go-along interviews in
therapeutic places deemed important by participants.
Concepts of âfleeting timeâ, ârestorative timeâ and âbiographical timeâ are used,
alongside notions of individual agency, to examine participantsâ green and blue space
experiences in the context of the temporal structures characterising their everyday lives and
the biographical experiences contributing to the perceived importance of such settings over
time. In a culture that by and large prioritises speed, dominated by social ideals of, for
example, the âproductive workerâ and the âgood parentâ, participants conveyed a desire to
shift from âfleeting timeâ to ârestorative timeâ, seeking a balance between embodied stillness and therapeutic mobility. This was deemed particularly important during more stressful life
transitions, such as parenthood, employment shifts and the onset of illness or impairment,
when participants worked hard to tailor their therapeutic geographies to shifting wellbeing
needs and priorities.This work was supported by the European Social Fund Convergence Programme for
Cornwall and the Isles of Scilly
Experiences and Expectations of Biographical Time among Young Athletes
In this article, we explore how biographical time is storied by a particular group of young athletes in relation to their experiences and expectations of embodied ageing. The data suggests that at present, as able and sporting bodies, their everyday experiences are framed by the cyclical, maximizing, and disciplined notions of time associated with the social organization of sport. In their middle years, however, it was perceived that time would be pressured. In contrast, when talking about old age, empty time and static time were expected. The ways in which three different narratives of self operate to shape the projected experiences of time for these individuals are highlighted, and the implications of this process for their ability to access diverse narrative resources of ageing is discussed
Security against eavesdropping in quantum cryptography
In this article we deal with the security of the BB84 quantum cryptography
protocol over noisy channels using generalized privacy amplification. For this
we estimate the fraction of bits needed to be discarded during the privacy
amplification step. This estimate is given for two scenarios, both of which
assume the eavesdropper to access each of the signals independently and take
error correction into account. One scenario does not allow a delay of the
eavesdropper's measurement of a measurement probe until he receives additional
classical information. In this scenario we achieve a sharp bound. The other
scenario allows a measurement delay, so that the general attack of an
eavesdropper on individual signals is covered. This bound is not sharp but
allows a practical implementation of the protocol.Comment: 11 pages including 3 figures, contains new results not contained in
my Phys. Rev. A pape
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