4,217 research outputs found
The End of Modernity : what the financial and environmental crisis is really telling us
No full textGlobal financial crisis, global environmental crisis - what connects them? Stuart Sim claims they are both symptoms of the end of modernity, the cultural system that has prevailed in the West from the Enlightenment onwards. In this provocative book, Sim argues that the modern world's insatiable need for technologically driven economic progress is unsustainable, and potentially destructive of the planet and its socio-economic systems. The new landscape this creates - socially, politically, economically, intellectually - is explored through an interdisciplinary approach, providing a wide-ranging assessment of the collapse of modernity and the challenges it poses us. Sim calls for a radical alteration in our world view and for purposeful changes both to our economic and intellectual life: we need to jettison the free market, rein in conspicuous consumption, reinvigorate public service, and develop talents other than the entrepreneurial if we are to reconstruct our society satisfactorily
No. 617 Stuart Ruckman
No full textTranscript (12, 40 pages) of two interviews by Matt Driscoll with Stuart Ruckman on April 9, 2010, and July 7, 2011Ruckman (b. 1966) was born in Salt Lake City, Utah. Stuart shares how his family, particularly his father, played a significant role in introducing him to the outdoors. Some of his initial explorations included a hike to the top of Mount Olympus when he was five years old, backpacking trips in the Wasatch and Uinta Mountains, and a successful summit attempt on the Grand Teton when he was twelve. Stuart discovered technical rock climbing due to the influence of his older brother Bret, five years Stuart\u27s senior. Bret learned under Dennis Turville, a well-respected Salt Lake climbing instructor. Stuart shares his observations on the Salt Lake climbing community of the late 1970s and 1980s, noting the intimacy of the community, while also pointing out the significant influence of a handful of climbers, including Merrill Bitter, Les Ellison, and Brian Smoot. He briefly describes the proliferation of new-route development in the Wasatch during his first decade in climbing. In collaboration with his brother Bret, Stuart published comprehensive guidebooks on climbing in the Wasatch Mountains. Stuart\u27s contributions as a first-ascensionist and co-author of Rock Climbing the Wasatch Range attest to his lasting impact on Utah climbing. Interview is part of the Outdoor Recreation History Project. Interviewer: Matt Driscol
State-of-the-art simulations of line-driven accretion disc winds: realistic radiation-hydrodynamics leads to weaker outflows
No full textDisc winds are a common feature in accreting astrophysical systems on all scales. In active galactic nuclei (AGN) and accreting white dwarfs (AWDs), specifically, radiation pressure mediated by spectral lines is a promising mechanism for driving these outflows. Previous hydrodynamical simulations have largely supported this idea, but relied on highly approximate treatments of ionization and radiative transfer. Given the sensitivity of line driving to the ionization state and radiation field in the outflow, here we present a new method for carrying out 2.5D radiation-hydrodynamic simulations that takes full account of the frequency-dependent radiative transfer through the wind, the corresponding ionization state and the resulting radiative accelerations. Applying our method to AWDs, we find that it is much harder to drive a powerful line-driven outflow when the interaction between matter and radiation is treated self-consistently. This conclusion is robust to changes in the adopted system parameters. The fundamental difficulty is that discs luminous enough to drive such a wind are also hot enough to over-ionize it. As a result, the mass-loss rates in our simulations are much lower than those found in earlier, more approximate calculations. We also show that the ultraviolet spectra produced by our simulations do not match those observed in AWDs. We conclude that, unless the over-ionization problem can be mitigated (e.g. by sub-grid clumping or a softer-than-expected radiation field), line driving may not be a promising mechanism for powering the outflows from AWDs. These conclusions are likely to have significant implications for disc winds in AGN also
Tolko Industries treasurer Fred Stehle signing documents with president Bill Sim, Marg Sim and Stuart Park
No full textWorld class science centre opening this fall in Vernon. Surrounded by displays that will find a permanent home downstairs, Tolko Industries secretary/treasurer Fred Stehle (R) signs documents releasing part of the lower floor of the company's downtown office building to the Vernon Science and Discovery centre, represented by president Bill Sim (seated), his wife Marg and the group's secretary Stuart Park. Used on pg. 3 of the June 29 1990 newspaper
A diagnostic kit for optical emission lines shaped by accretion disc winds
Full text linkBlueshifted absorption is the classic spectroscopic signature of an accretion disc wind in X-ray binaries and cataclysmic variables (CVs). However, outflows can also create pure emission lines, especially at optical wavelengths. Therefore, developing other outflow diagnostics for these types of lines is worthwhile. With this in mind, we construct a systematic grid of 3645 synthetic wind-formed H α line profiles for CVs with the radiative transfer code sirocco. Our grid yields a variety of line shapes: symmetric, asymmetric, single- to quadruple-peaked, and even P-Cygni profiles. About 20percnt of these lines – our ‘Gold’ sample – have strengths and widths consistent with observations. We use this grid to test a recently proposed method for identifying wind-formed emission lines based on deviations in the wing profile shape: the ’excess equivalent width diagnostic diagram’. We find that our Gold sample can preferentially populate the suggested ‘wind regions’ of this diagram. However, the method is highly sensitive to the adopted definition of the line profile ‘wing’. Hence, we propose a refined definition based on the full-width at half maximum to improve the interpretability of the diagnostic diagram. Furthermore, we define an approximate scaling relation for the strengths of wind-formed CV emission lines in terms of the outflow parameters. This relation provides a fast way to assess whether – and what kind of – outflow can produce an observed emission line. All our wind-based models are open-source and we provide an easy-to-use web-based tool to browse our full set of H α spectral profiles
George MacLeod’s open-air preaching: performance and counter-performance
No full textStuart Blythe uses the methodology of performance to analyse George MacLeod’s open-air preaching. He points out that MacLeod’s preaching was derived from a theology of the incarnation, and an understanding of the paradoxes and dichotomies of common human life. This preaching, Blythe suggests, was also a counter-performance in the context of outlooks and ideologies inimical to the gospel. The paper raises interesting issues related to preaching as performance, and the further question as to whether or not the life and work of the Church as a whole might now be better understood as a counter-performance.Publisher PD
Redemption in the work of Francis Stuart
Full text linkThe idea of redemption is central to an understanding of the work
of Francis Stuart. Through an examination of its development and
expression, it is possible to demonstrate the integrity of his work and
its distinctive qualities. Such a demonstration is necessary because
Stuart's writing has been subjected to comparatively little scholarly
inquiry, although reviews of his work, especially that produced since
1949, suggest that it is impressive and important.
First, a general background to Stuart's work, a discussion of the
special problems associated with reading it, and a summary of his corpus
is provided. This indicates that the idea of redemption is important to
his earliest writing. The state of redemption is shown to be a
necessary apotheosis for Stuart's outcast heroes; it involves spiritual
suffering through which may be found a sense of reintegration and a
higher reality. This is expressed through interrelated themes such as
those of gambler, artist and ordinary man; mystic and criminal; sacred
and profane love; and spirituality and the mundane. The nature of the
redemptive experience is further elaborated by distinctive, complex
motifs, especially the hare, the ark and the woman-Christ. Their
recurrence provides an important element in the unity of Stuart's work.
Because Stuart's idea of the outcast raises important biographical
questions, an examination of the relationship between Stuart's life and
his work is made. Finally, the way in which the idea of redemption
exists in the language structures of Stuart's novels is examined, with
especial reference to his most recent work, The High Consistory. The
thesis shows that the development of the these of redemption
demonstrates the integrity of Stuart's work
Accretion disc winds in tidal disruption events: ultraviolet spectral lines as orientation indicators: ultraviolet spectral lines as orientation indicators
Full text linkSome tidal disruption events (TDEs) exhibit blueshifted broad absorption lines (BALs) in their rest-frame ultraviolet (UV) spectra, while others display broad emission lines (BELs). Similar phenomenology is observed in quasars and accreting white dwarfs, where it can be interpreted as an orientation effect associated with line formation in an accretion disc wind. We propose and explore a similar unification scheme for TDEs. We present synthetic UV spectra for disc and wind-hosting TDEs, produced by a state-of-the-art Monte Carlo ionization and radiative transfer code. Our models cover a wide range of disc wind geometries and kinematics. Such winds naturally reproduce both BALs and BELs. In general, sightlines looking into the wind cone preferentially produce BALs, while other orientations preferentially produce BELs. We also study the effect of wind clumping and CNO-processed abundances on the observed spectra. Clumpy winds tend to produce stronger UV emission and absorption lines, because clumping increases both the emission measure and the abundances of the relevant ionic species, the latter by reducing the ionization state of the outflow. The main effect of adopting CNO-processed abundances is a weakening of C iv 1550 Å and an enhancement of N v 1240 Å in the spectra. We conclude that line formation in an accretion disc wind is a promising mechanism for explaining the diverse UV spectra of TDEs. If this is correct, the relative number of BAL and BEL TDEs can be used to estimate the covering factor of the outflow. The models in this work are publicly available online and upon request
Does the amount of participation matter? Public comments, agency responses and the time to finalize a regulation
No full textThe notice and comment rulemaking process is a fundamental part of how agencies write regulations. While this process is starting to receive more empirical attention, the question of how the number of comments that an agency receives affects its decision-making process has received little examination. This paper uses Boolean analysis to examine nine rules from two agencies at the Department of Health and Human Services and evaluates the impact of a high volume of comments on agency changes to proposed rules and the time an agency takes to finalize a proposed rule. These nine cases suggest that agencies are most likely to change their proposals when they receive a high volume of comments on highly complex rules that are not very politically salient. Highly complex rules are also likely to take a long time to finalize when there are many public comments however it is often other factors that cause a long delay between proposed and final rules.Peer reviewedThe final publication is available at Springer via http://dx.doi.org/10.1007/s11077-007-9051-
Radiation-hydrodynamic simulations of thermally-driven disc winds in X-ray binaries: a direct comparison to GRO J1655-40
Full text linkEssentially all low-mass X-ray binaries (LMXBs) in the soft state appear to drive powerful equatorial disc winds. A simple mechanism for driving such outflows involves X-ray heating of the top of the disc atmosphere to the Compton temperature. Beyond the Compton radius, the thermal speed exceeds the escape velocity, and mass loss is inevitable. Here, we present the first coupled radiation-hydrodynamic simulation of such thermally-driven disc winds. The main advance over previous modelling efforts is that the frequency-dependent attenuation of the irradiating SED is taken into account. We can therefore relax the approximation that the wind is optically thin throughout which is unlikely to hold in the crucial acceleration zone of the flow. The main remaining limitations of our simulations are connected to our treatment of optically thick regions. Adopting parameters representative of the wind-driving LMXB GRO~J1655-40, our radiation-hydrodynamic model yields a mass-loss rate that is lower than that suggested by pure hydrodynamic, optically thin models. This outflow rate still represents more than twice the accretion rate and agrees well with the mass-loss rate inferred from Chandra/HETG observations of GRO~J1655-40 at a time when the system had a similar luminosity to that adopted in our simulations. The Fe XXV and Fe XXVI Lyman absorption line profiles observed in this state are slightly stronger than those predicted by our simulations but the qualitative agreement between observed and simulated outflow properties means that thermal driving is a viable mechanism for powering the disc winds seen in soft-state LMXBs
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