1,907 research outputs found
Clinical and service implications of a cognitive analytic therapy model of psychosis
Cognitive analytic therapy (CAT) is an integrative, interpersonal model of therapy predicated on a radically social concept of self, developed over recent years in the UK by Anthony Ryle. A CAT-based model of psychotic disorder has been developed much more recently based on encouraging early experience in this area. The model describes and accounts for many psychotic experiences and symptoms in terms of distorted, amplified or muddled enactments of normal or âneuroticâ reciprocal role procedures (RRPs) and of damage at a meta-procedural level to the structures of the self.
Reciprocal role procedures are understood in CAT to represent the outcome of the process of internalization of early, sign-mediated, interpersonal experience and to constitute the basis for all mental activity, normal or otherwise. Enactments of maladaptive RRPs generated by early interpersonal stress are seen in this model to constitute a form of âinternal expressed emotionâ. Joint description of these RRPs and their enactments (both internally and externally) and their subsequent revision is central to the practice of CAT during which they are mapped out through written and diagrammatic reformulations.
This model may usefully complement and extend existing approaches, notably recent CBT-based interventions, particularly with âdifficultâ patients, and generate meaningful and helpful understandings of these disorders for both patients and their treating teams. We suggest that use of a coherent and robust model such as CAT could have important clinical and service implications in terms of developing and researching models of these disorders as well as for the training of multidisciplinary teams in their effective treatment
Resolving the Radio Source Background: Deeper Understanding Through Confusion
We used the Karl G. Jansky Very Large Array (VLA) to image one primary beam
area at 3 GHz with 8 arcsec FWHM resolution and 1.0 microJy/beam rms noise near
the pointing center. The P(D) distribution from the central 10 arcmin of this
confusion-limited image constrains the count of discrete sources in the 1 <
S(microJy/beam) < 10 range. At this level the brightness-weighted differential
count S^2 n(S) is converging rapidly, as predicted by evolutionary models in
which the faintest radio sources are star-forming galaxies; and ~96$% of the
background originating in galaxies has been resolved into discrete sources.
About 63% of the radio background is produced by AGNs, and the remaining 37%
comes from star-forming galaxies that obey the far-infrared (FIR) / radio
correlation and account for most of the FIR background at lambda = 160 microns.
Our new data confirm that radio sources powered by AGNs and star formation
evolve at about the same rate, a result consistent with AGN feedback and the
rough correlation of black hole and bulge stellar masses. The confusion at
centimeter wavelengths is low enough that neither the planned SKA nor its
pathfinder ASKAP EMU survey should be confusion limited, and the ultimate
source detection limit imposed by "natural" confusion is < 0.01 microJy at 1.4
GHz. If discrete sources dominate the bright extragalactic background reported
by ARCADE2 at 3.3 GHz, they cannot be located in or near galaxies and most are
< 0.03 microJy at 1.4 GHz.Comment: 28 pages including 16 figures. ApJ accepted for publicatio
Community policing on a limited budget: a look at how departments approach the challenge
Explores ways that police departments can implement community policing on a limited budge
Correlated X-ray and Optical Variability in Mkn 509
We present results of a 3 year monitoring campaign of the Seyfert 1 galaxy
Markarian 509, using X-ray data from the Rossi X-ray Timing Explorer (RXTE) and
optical data taken by the SMARTS consortium. Both light curves show significant
variations, and are strongly correlated with the optical flux leading the X-ray
flux by 15 days. The X-ray power spectrum shows a steep high-frequency slope of
-2.0, breaking to a slope of -1.0 at at timescale of 34 days. The lag from
optical to X-ray emission is most likely caused by variations in the accretion
disk propagating inward.Comment: 13 pages, 3 figures. Accepted for publication in the Astrophysical
Journa
Personal and sub-personal: a defence of Dennett's early distinction
Since 1969, when Dennett introduced a distinction between personal and subâpersonal levels of explanation, many philosophers have used âsubâpersonalâ very loosely, and Dennett himself has abandoned a view of the personal level as genuinely autonomous. I recommend a position in which Dennett's original distinction is crucial, by arguing that the phenomenon called mental causation is on view only at the properly personal level. If one retains the commitââ ments incurred by Dennett's early distinction, then one has a satisfactory antiâphysicalistic, antiâdualist philosophy of mind. It neither interferes with the projects of subâpersonal psychology, nor encourages ; instrumentalism at the personal level.
People lose sight of Dennettâs personal/sub-personal distinction because they free it from its philosophical moorings. A distinction that serves a philosophical purpose is typically rooted in doctrine; it cannot be lifted out of context and continue to do its work. So I shall start from Dennettâs distinction as I read it in its original context. And when I speak of âthe distinctionâ, I mean to point not only towards the terms that Dennett first used to define it but also towards the philosophical setting within which its work was cut out
Radial Velocities of Six OB Stars
We present new results from a radial velocity study of six bright OB stars
with little or no prior measurements. One of these, HD 45314, may be a
long-period binary, but the velocity variations of this Be star may be related
to changes in its circumstellar disk. Significant velocity variations were also
found for HD 60848 (possibly related to nonradial pulsations) and HD 61827
(related to wind variations). The other three targets, HD 46150, HD 54879, and
HD 206183, are constant velocity objects, but we note that HD 54879 has
H emission that may originate from a binary companion. We illustrate
the average red spectrum of each target.Comment: Accepted for publication in PASP July 2007 issu
The 74MHz System on the Very Large Array
The Naval Research Laboratory and the National Radio Astronomy Observatory
completed implementation of a low frequency capability on the VLA at 73.8 MHz
in 1998. This frequency band offers unprecedented sensitivity (~25 mJy/beam)
and resolution (~25 arcsec) for low-frequency observations. We review the
hardware, the calibration and imaging strategies, comparing them to those at
higher frequencies, including aspects of interference excision and wide-field
imaging. Ionospheric phase fluctuations pose the major difficulty in
calibrating the array. Over restricted fields of view or at times of extremely
quiescent ionospheric ``weather'', an angle-invariant calibration strategy can
be used. In this approach a single phase correction is devised for each
antenna, typically via self-calibration. Over larger fields of view or at times
of more normal ionospheric ``weather'' when the ionospheric isoplanatic patch
size is smaller than the field of view, we adopt a field-based strategy in
which the phase correction depends upon location within the field of view. This
second calibration strategy was implemented by modeling the ionosphere above
the array using Zernike polynomials. Images of 3C sources of moderate strength
are provided as examples of routine, angle-invariant calibration and imaging.
Flux density measurements indicate that the 74 MHz flux scale at the VLA is
stable to a few percent, and tied to the Baars et al. value of Cygnus A at the
5 percent level. We also present an example of a wide-field image, devoid of
bright objects and containing hundreds of weaker sources, constructed from the
field-based calibration. We close with a summary of lessons the 74 MHz system
offers as a model for new and developing low-frequency telescopes. (Abridged)Comment: 73 pages, 46 jpeg figures, to appear in ApJ
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Managing digital coordination of design: emerging hybrid practices in an institutionalized project setting
What happens when digital coordination practices are introduced into the institutionalized setting of an engineering project? This question is addressed through an interpretive study that examines how a shared digital model becomes used in the late design stages of a major station refurbishment project. The paper contributes by mobilizing the idea of âhybrid practicesâ to understand the diverse patterns of activity that emerge to manage digital coordination of design. It articulates how engineering and architecture professions develop different relationships with the shared model; the design team negotiates paper-based practices across organizational boundaries; and diverse practitioners probe the potential and limitations of the digital infrastructure. While different software packages and tools have become linked together into an integrated digital infrastructure, these emerging hybrid practices contrast with the interactions anticipated in practice and policy guidance and presenting new opportunities and challenges for managing project delivery. The study has implications for researchers working in the growing field of empirical work on engineering project organizations as it shows the importance of considering, and suggests new ways to theorise, the introduction of digital coordination practices into these institutionalized settings
Multispectral lensless digital holographic microscope: imaging MCF-7 and MDA-MB-231 cancer cell cultures
Digital holography is the process where an objectâs phase and amplitude information is retrieved from intensity images
obtained using a digital camera (e.g. CCD or CMOS sensor). In-line digital holographic techniques offer full use of the
recording deviceâs sampling bandwidth, unlike off-axis holography where object information is not modulated onto
carrier fringes. Reconstructed images are obscured by the linear superposition of the unwanted, out of focus, twin
images. In addition to this, speckle noise degrades overall quality of the reconstructed images. The speckle effect is a
phenomenon of laser sources used in digital holographic systems. Minimizing the effects due to speckle noise, removal
of the twin image and using the full sampling bandwidth of the capture device aids overall reconstructed image quality.
Such improvements applied to digital holography can benefit applications such as holographic microscopy where the
reconstructed images are obscured with twin image information. Overcoming such problems allows greater flexibility in
current image processing techniques, which can be applied to segmenting biological cells (e.g. MCF-7 and MDA-MB-
231) to determine their overall cell density and viability. This could potentially be used to distinguish between apoptotic
and necrotic cells in large scale mammalian cell processes, currently the system of choice, within the biopharmaceutical
industry
A Brief History of AGN
Astronomers knew early in the twentieth century that some galaxies have
emission-line nuclei. However, even the systematic study by Seyfert (1943) was
not enough to launch active galactic nuclei (AGN) as a major topic of
astronomy. The advances in radio astronomy in the 1950s revealed a new universe
of energetic phenomena, and inevitably led to the discovery of quasars. These
discoveries demanded the attention of observers and theorists, and AGN have
been a subject of intense effort ever since. Only a year after the recognition
of the redshifts of 3C 273 and 3C 48 in 1963, the idea of energy production by
accretion onto a black hole was advanced. However, acceptance of this idea came
slowly, encouraged by the discovery of black hole X-ray sources in our Galaxy
and, more recently, supermassive black holes in the center of the Milky Way and
other galaxies. Many questions remain as to the formation and fueling of the
hole, the geometry of the central regions, the detailed emission mechanisms,
the production of jets, and other aspects. The study of AGN will remain a
vigorous part of astronomy for the foreseeable future.Comment: 37 pages, no figures. Uses aaspp4.sty. To be published in
Publications of the Astronomical Society of the Pacific, 1999 Jun
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