6,176 research outputs found
'The world is full of big bad wolves': investigating the experimental therapeutic spaces of R.D. Laing and Aaron Esterson
In conjunction with the recent critical assessments of the life and work of R.D. Laing, this paper seeks to demonstrate what is revealed when Laing’s work on families and created spaces of mental health care are examined through a geographical lens. The paper begins with an exploration of Laing’s time at the Tavistock Clinic in London during the 1960s, and of the co-authored text with Aaron Esterson entitled, Sanity, Madness and the Family (1964). The study then seeks to demonstrate the importance Laing and his colleague placed on the time-space situatedness of patients and their worlds. Finally, an account is provided of Laing’s and Esterson’s spatial thinking in relation to their creation of both real and imagined spaces of therapeutic care
Structures of the magnetoionic media around the FR I radio galaxies 3C 31 and Hydra A
We use high-quality VLA images of the Fanaroff & Riley Class I radio galaxy
3C 31 at six frequencies in the range 1365 to 8440MHz to explore the spatial
scale and origin of the rotation measure (RM) fluctuations on the line of sight
to the radio source. We analyse the distribution of the degree of polarization
to show that the large depolarization asymmetry between the North and South
sides of the source seen in earlier work largely disappears as the resolution
is increased. We show that the depolarization seen at low resolution results
primarily from unresolved gradients in a Faraday screen in front of the
synchrotron-emitting plasma. We establish that the residual degree of
polarization in the short-wavelength limit should follow a Burn law and we fit
such a law to our data to estimate the residual depolarization at high
resolution. We show that the observed RM variations over selected areas of 3C
31 are consistent with a power spectrum of magnetic fluctuations in front of 3C
31 whose power-law slope changes significantly on the scales sampled by our
data. The power spectrum can only have the form expected for Kolmogorov
turbulence on scales <5 kpc. On larger scales we find a flatter slope. We also
compare the global variations of RM across 3C 31 with the results of
three-dimensional simulations of the magnetic-field fluctuations in the
surrounding magnetoionic medium. We show that our data are consistent with a
field distribution that favours the plane perpendicular to the jet axis -
probably because the radio source has evacuated a large cavity in the
surrounding medium. We also apply our analysis techniques to the case of Hydra
A, where the shape and the size of the cavities produced by the source in the
surrounding medium are known from X-ray data. (Abridged)Comment: 33 pages, 25 figures, accepted for publication in MNRA
Protecting the rights of patients in psychiatric settings:A comparison of the work of the Mental Health Act Commission with the Care Quality Commission
Chimera states in networks of phase oscillators: the case of two small populations
Chimera states are dynamical patterns in networks of coupled oscillators in
which regions of synchronous and asynchronous oscillation coexist. Although
these states are typically observed in large ensembles of oscillators and
analyzed in the continuum limit, chimeras may also occur in systems with finite
(and small) numbers of oscillators. Focusing on networks of phase
oscillators that are organized in two groups, we find that chimera states,
corresponding to attracting periodic orbits, appear with as few as two
oscillators per group and demonstrate that for the bifurcations that
create them are analogous to those observed in the continuum limit. These
findings suggest that chimeras, which bear striking similarities to dynamical
patterns in nature, are observable and robust in small networks that are
relevant to a variety of real-world systems.Comment: 13 pages, 16 figure
Nonlinear stability of relativistic sheared planar jets
The linear and non-linear stability of sheared, relativistic planar jets is
studied by means of linear stability analysis and numerical hydrodynamical
simulations. Our results extend the previous Kelvin-Hemlholtz stability studies
for relativistic, planar jets in the vortex sheet approximation performed by
Perucho et al. (2004a,b) by including a shear layer between the jet and the
external medium and more general perturbations. The models considered span a
wide range of Lorentz factors () and internal energies () and are classified into three classes according to the main
characteristics of their long-term, non-linear evolution. We observe a clear
separation of these three groups in a relativistic Mach-number Lorentz-factor
plane. Jets with a low Lorentz factor and small relativistic Mach number are
disrupted after saturation. Those with a large Lorentz factor and large
relativistic Mach number are the stablest, due to the appearance of short
wavelength resonant modes which generate local mixing and heating in the shear
layer around a fast, unmixed core, giving a plausible solution for the problem
of the long-term stability of relativistic jets. A third group is present
between them, including jets with intermediate values of Lorentz factor and
relativistic Mach number, which are disrupted by a slow process of mixing
favored by an efficient and continuous conversion of kinetic into internal
energy. In the long term, all the models develop a distinct transversal
structure (shear/transition layers) as a consequence of KH perturbation growth,
depending on the class they belong to. The properties of these shear layers are
analyzed in connection with the parameters of the original jet models.Comment: accepted for publication in A&A (in press). High resolution plots,
figures and Appendices of the paper will be found in the online version of
the paper in A&A, and on request to [email protected]
Drought Monitoring and Advisory Services in South Africa
The normal total rainfall for the summer rainfall areas in South Africa is 664 mm. Since 1963, the country has recorded 16 seasons below normal and 14 above normal. Since the 1982–83 season, 7 seasons have been below normal and 4 have been above normal. Of these last 11 years, two rainy seasons recorded less than 75% of normal rainfall, which is a coarse estimation of severe drought. These seasons were 1982–83, when an average total of only 408 mm was measured, and 1992–93, when the average total was 484 mm. Although 1991–92 has been called the worst drought this century, for the stations used in this survey, the average total was 510 mm, or about 77% of normal. The 1981–82 and 1982–83 as well as 1991–92 and 1992–93 seasons were close to being only 75% of normal rainfall. These are the only occasions in the last 70 years that two consecutive summer rainy seasons have had such seriously inadequate rainfall. Fortunately, the geographical and temporal distribution of rainfall varies seasonally, and in 1992–93, adequate rain fell on the main summer cropping areas of South Africa to save the country from experiencing two disastrous crop failures. The greatest impacts of these two very dry seasons were the low levels of surface water stored in dams on which most industrial and urban areas depend and low ground water reserves for boreholes, which support most irrigation and many rural communities. In addition, the sugar industry in Natal and Zululand on the normally wet east coast has been seriously damaged and many sugar mills have closed. Farming and rural communities with accumulated capital losses and mounting debt cannot hope to recover as quickly as the grazing grasses did following good rains in October and November 1993
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