5,710 research outputs found
3D wedge filling and 2D random-bond wetting
Fluids adsorbed in 3D wedges are shown to exhibit two types of continuous
interfacial unbinding corresponding to critical and tricritical filling
respectively. Analytic solution of an effective interfacial model based on the
transfer-matrix formalism allows us to obtain the asymptotic probability
distribution functions for the interfacial height when criticality and
tricriticality are approached. Generalised random walk arguments show that, for
systems with short-ranged forces, the critical singularities at these
transitions are related to 2D complete and critical wetting with random bond
disorder respectively.Comment: 7 pages, 3 figures, accepted for publication in Europhysics Letter
Physical education as Olympic education
Introduction
In a recent paper (Parry, 1998, p. 64), I argued that
the justification of PE activities lies in their capacity to facilitate the development of certain human excellences of a valued kind. Of course, the problem now lies in specifying those ‘human excellences of a valued kind’, and (for anyone) this task leads us into the area of philosophical anthropology.
I suggested that the way forward for Physical Education lies in the philosophical anthropology (and the ethical ideals) of Olympism, which provide a specification of a variety of human values and excellences which:
•have been attractive to human groups over an impressive span of time and space
•have contributed massively to our historically developed conceptions of ourselves
•have helped to develop a range of artistic and cultural conceptions that have defined Western culture.
•have produced a range of physical activities that have been found universally satisfying and challenging.
Although physical activities are widely considered to be pleasurable, their likelihood of gaining wide acceptance lies rather in their intrinsic value, which transcends the simply hedonic or relative good. Their ability to furnish us with pleasurable experiences depends upon our prior recognition in them of opportunities for the development and expression of valued human excellences. They are widely considered to be such opportunities for the expression of valued human excellences because, even when as local instantiations, their object is to challenge our common human propensities and abilities.
I claimed that Olympic ideals may be seen not merely as inert ‘ideals’, but living ideas which have the power to remake our notions of sport in education, seeing sport not as mere physical activity but as the cultural and developmental activity of an aspiring, achieving, well-balanced, educated and ethical individual.
This paper seeks to make good that claim by trying to develop a case for Physical Education as Olympic Education. I begin by setting out various accounts and conceptions of the Olympic Idea; then I suggest a unifying and organising account of the philosophical anthropology of Olympism; and this is followed by the practical application of that account in two examples of current ethical issues. Finally, I seek to present an account of Physical Education as Olympic Education
Optimal Extraction of Fibre Optic Spectroscopy
We report an optimal extraction methodology, for the reduction of
multi-object fibre spectroscopy data, operating in the regime of tightly packed
(and hence significantly overlapping) fibre profiles. The routine minimises
crosstalk between adjacent fibres and statistically weights the extraction to
reduce noise. As an example of the process we use simulations of the numerous
modes of operation of the AAOmega fibre spectrograph and observational data
from the SPIRAL Integral Field Unit at the Anglo-Australian Telescope.Comment: Accepted for publication in PAS
Correlation function algebra for inhomogeneous fluids
We consider variational (density functional) models of fluids confined in
parallel-plate geometries (with walls situated in the planes z=0 and z=L
respectively) and focus on the structure of the pair correlation function
G(r_1,r_2). We show that for local variational models there exist two
non-trivial identities relating both the transverse Fourier transform G(z_\mu,
z_\nu;q) and the zeroth moment G_0(z_\mu,z_\nu) at different positions z_1, z_2
and z_3. These relations form an algebra which severely restricts the possible
form of the function G_0(z_\mu,z_\nu). For the common situations in which the
equilibrium one-body (magnetization/number density) profile m_0(z) exhibits an
odd or even reflection symmetry in the z=L/2 plane the algebra simplifies
considerably and is used to relate the correlation function to the finite-size
excess free-energy \gamma(L). We rederive non-trivial scaling expressions for
the finite-size contribution to the free-energy at bulk criticality and for
systems where large scale interfacial fluctuations are present. Extensions to
non-planar geometries are also considered.Comment: 15 pages, RevTex, 4 eps figures. To appear in J.Phys.Condens.Matte
To what extent do youth-focused prevention programmes reflect evidence-based practices? Findings from an audit of alcohol and other drug prevention programmes in Cape Town, South Africa
Despite considerable effort directed towards youth focused prevention activities in South Africa, little is known about the content of these activities. A major concern is the extent to which substance abuse prevention programmes reflect evidence-based practices (EBPs). This paper reports on the findings from a cross-sectional audit of youth-focused alcohol and other drug prevention programmes conducted in the Cape Town Metropole in 2007. This audit explored the extent to
which EBPs are used in prevention programmes and examined possible barriers to their adoption. Key findings suggest that most prevention programmes are not guided by EBP and are implemented in the absence of evidence on their effectiveness. The lack of a national regulatory regime for prevention programmes and limited funding are major barriers to implementing sustainable and effective prevention programmes. Based on these findings, strategies to assist in improving substance abuse prevention services and recommendations for improving service delivery systems are provided.
Key Words: Youth, prevention programmes, South Africa, evidence-based practice
Localization of staff in a hostile context: An exploratory investigation in Afghanistan
Hostile environments pose a distinct threat to international organizations and their staff and yet they are under researched within the literature on IHRM. Localization of staff may present a means to manage some of the risks and also to provide the resources needed to achieve competitive advantage. Drawing on the resource-based view and institutional theory, we explored resource- and capability-based and institutional influences in relation to the decision of whether to localize professional staff in a hostile environment (Afghanistan). Using in-depth semi-structured interviews with representatives from four organizations in Afghanistan, our investigation identified new influences on localization at the societal and organizational level. These include ongoing security issues as well as influences on localization such as corruption, impartiality and the need for outside experiences as well as perspectives not identified in previous work. In addition, we emphasize the importance of both picking appropriate valuable local human resources and using appropriate internal capabilities to develop and deploy them in such a way to build firm-specific assets which are also rare, inimitable and non-substitutable, thus leading to sustainable competitive advantage
Direct imaging of a digital-micromirror device for configurable microscopic optical potentials
Programable spatial light modulators (SLMs) have significantly advanced the
configurable optical trapping of particles. Typically, these devices are
utilized in the Fourier plane of an optical system, but direct imaging of an
amplitude pattern can potentially result in increased simplicity and
computational speed. Here we demonstrate high-resolution direct imaging of a
digital micromirror device (DMD) at high numerical apertures (NA), which we
apply to the optical trapping of a Bose-Einstein condensate (BEC). We utilise a
(1200 x 1920) pixel DMD and commercially available 0.45 NA microscope
objectives, finding that atoms confined in a hybrid optical/magnetic or
all-optical potential can be patterned using repulsive blue-detuned (532 nm)
light with 630(10) nm full-width at half-maximum (FWHM) resolution, within 5%
of the diffraction limit. The result is near arbitrary control of the density
the BEC without the need for expensive custom optics. We also introduce the
technique of time-averaged DMD potentials, demonstrating the ability to produce
multiple grayscale levels with minimal heating of the atomic cloud, by
utilising the high switching speed (20 kHz maximum) of the DMD. These
techniques will enable the realization and control of diverse optical
potentials for superfluid dynamics and atomtronics applications with quantum
gases. The performance of this system in a direct imaging configuration has
wider application for optical trapping at non-trivial NAs.Comment: 9 page
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