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Lorrie Moore: Mo(o)re than an interim assessment
Lorrie Moore has long shed the image of the precocious talent who won the Seventeen story prize with her first submission as a nineteen-year-old undergraduate, but there is still a sense that her best work may be yet to come. In that respect, this mini special issue represents by no means the final word on Moore, but rather an interim assessment of a career that is already substantial and that promises much more to come. Together these three essays (and introduction) offer a coherent and striking exploration of Moore's work that develops new directions for future criticism and will help cement her growing reputation as one of the most original and distinctive contemporary writers. They sometimes circle around the same stories, even the same quotations, reading them in a variety of frames and picking up (and at) the nuances of Moore's sustained wordplay and careful documenting of space, of identity, of gender. Thus these essays work together rather than separately, layering over multiple understandings of Moore's incisive American literature
Effectiveness and reach of a directed-population approach to improving dental health and reducing inequalities: a cross sectional study
Background
Childsmile School adopts a directed-population approach to target fluoride varnish applications to 20% of the primary one (P1) population in priority schools selected on the basis of the proportion of enrolled children considered to be at increased-risk of developing dental caries. The study sought to compare the effectiveness of four different methods for identifying individuals most in need when a directed-population approach is taken. <p></p>
Methods
The 2008 Basic National Dental Inspection Programme (BNDIP) cross-sectional P1 Scottish epidemiological survey dataset was used to model four methods and test three definitions of increased-risk. Effectiveness was determined by the positive predictive value (PPV) and explored in relation to 1-sensitivity and 1-specificity. <p></p>
Results
Complete data was available on 43470 children (87% of the survey). At the Scotland level, at least half (50%) of the children targeted were at increased-risk irrespective of the method used to target or the definition of increased-risk. There was no one method across all definitions of <i>increased-risk</i> that maximised PPV. Instead, PPV was highest when the targeting method complimented the definition of <i>increased-risk</i>. There was a higher percentage of children at <i>increased-risk</i> who were not targeted (1-sensitivity) when caries experience (rather than deprivation) was used to define <i>increased-risk</i>, irrespective of the method used for targeting. Over all three definitions of <i>increased-risk</i>, there was no one method that minimised (1-sensitivity) although this was lowest when the method and definition of <i>increased-risk</i> were complimentary. The false positive rate (1-specificity) for all methods and all definitions of <i>increased-risk</i> was consistently low (<20%), again being lowest when the method and definition of <i>increased-risk</i> were complimentary. <p></p>
Conclusion
Developing a method to reach all (or even the vast majority) of individuals at <i>increased-risk</i> defined by either caries experience or deprivation is difficult using a directed-population approach at a group level. There is a need for a wider debate between politicians and public health experts to decide how best to reach those most at need of intervention to improve health and reduce inequalities. <p></p>
Binary open clusters in the Milky Way: photometric and spectroscopic analysis of NGC 5617 and Trumpler 22
Using photometry and high resolution spectroscopy we investigate for the
first time the physical connection between the open clusters NGC 5617 and
Trumpler 22. Based on new CCD photometry we report their spatial proximity and
common age of ~70 Myr. Based on high resolution spectra collected using the
HERMES and UCLES spectrographs on the Anglo-Australian telescope, we present
radial velocities and abundances for Fe, Na, Mg, Al, Si, Ca and Ni. The
measured radial velocities are -38.63 +/-2.25 km/s for NGC 5617 and -38.46
+/-2.08 km/s for Trumpler 22. The mean metallicity of NGC 5617 was found to be
[Fe/H] =-0.18 +/-0.02 and for Trumpler 22 was found to be [Fe/H] = -0.17
+/-0.04. The two clusters share similar abundances across the other elements,
indicative of a common chemical enrichment history of these clusters. Together
with common motions and ages we confirm that NGC 5617 and Trumpler 22 are a
primordial binary cluster pair in the Milky Way.Comment: 7 pages, 3 figure, accepted by MNRA
Advanced electrostatic ion thruster for space propulsion
The suitability of the baseline 30 cm thruster for future space missions was examined. Preliminary design concepts for several advanced thrusters were developed to assess the potential practical difficulties of a new design. Useful methodologies were produced for assessing both planetary and earth orbit missions. Payload performance as a function of propulsion system technology level and cost sensitivity to propulsion system technology level are among the topics assessed. A 50 cm diameter thruster designed to operate with a beam voltage of about 2400 V is suggested to satisfy most of the requirements of future space missions
Seeing with sound? Exploring different characteristics of a visual-to-auditory sensory substitution device
Sensory substitution devices convert live visual images into auditory signals, for example with a web camera (to record the images), a computer (to perform the conversion) and headphones (to listen to the sounds). In a series of three experiments, the performance of one such device (‘The vOICe’) was assessed under various conditions on blindfolded sighted participants. The main task that we used involved identifying and locating objects placed on a table by holding a webcam (like a flashlight) or wearing it on the head (like a miner’s light). Identifying objects on a table was easier with a hand-held device, but locating the objects was easier with a head-mounted device. Brightness converted into loudness was less effective than the reverse contrast (dark being loud), suggesting that performance under these conditions (natural indoor lighting, novice users) is related more to the properties of the auditory signal (ie the amount of noise in it) than the cross-modal association between loudness and brightness. Individual differences in musical memory (detecting pitch changes in two sequences of notes) was related to the time taken to identify or recognise objects, but individual differences in self-reported vividness of visual imagery did not reliably predict performance across the experiments. In general, the results suggest that the auditory characteristics of the device may be more important for initial learning than visual associations
Interaction of Supernova Ejecta with Nearby Protoplanetary Disks
The early Solar System contained short-lived radionuclides such as 60Fe (t1/2
= 1.5 Myr) whose most likely source was a nearby supernova. Previous models of
Solar System formation considered a supernova shock that triggered the collapse
of the Sun's nascent molecular cloud. We advocate an alternative hypothesis,
that the Solar System's protoplanetary disk had already formed when a very
close (< 1 pc) supernova injected radioactive material directly into the disk.
We conduct the first numerical simulations designed to answer two questions
related to this hypothesis: will the disk be destroyed by such a close
supernova; and will any of the ejecta be mixed into the disk? Our simulations
demonstrate that the disk does not absorb enough momentum from the shock to
escape the protostar to which it is bound. Only low amounts (< 1%) of mass loss
occur, due to stripping by Kelvin-Helmholtz instabilities across the top of the
disk, which also mix into the disk about 1% of the intercepted ejecta. These
low efficiencies of destruction and injectation are due to the fact that the
high disk pressures prevent the ejecta from penetrating far into the disk
before stalling. Injection of gas-phase ejecta is too inefficient to be
consistent with the abundances of radionuclides inferred from meteorites. On
the other hand, the radionuclides found in meteorites would have condensed into
dust grains in the supernova ejecta, and we argue that such grains will be
injected directly into the disk with nearly 100% efficiency. The meteoritic
abundances of the short-lived radionuclides such as 60Fe therefore are
consistent with injection of grains condensed from the ejecta of a nearby (< 1
pc) supernova, into an already-formed protoplanetary disk.Comment: 57 pages, 16 figure
Practitioner perspectives on strategies to promote longer-term benefits of acupuncture or counselling for depression: a qualitative study
Background: Non-pharmacological interventions for depression may help patients manage their condition. Evidence from a recent large-scale trial (ACUDep) suggests that acupuncture and counselling can provide longer-term benefits for many patients with depression. This paper describes the strategies practitioners reported using to promote longer-term benefits for their patients. Methods: A qualitative sub-study of practitioners (acupuncturists and counsellors) embedded in a randomised controlled trial. Using topic guides, data was collected from telephone interviews and a focus group, altogether involving 19 counsellors and 17 acupuncturists. Data were audio recorded, transcribed verbatim and analysed using thematic content analysis. Results: For longer-term impact, both acupuncturists and counsellors encouraged insight into root causes of depression on an individual basis and saw small incremental changes as precursors to sustained benefit. Acupuncturists stressed the importance of addressing concurrent physical symptoms, for example helping patients relax or sleep better in order to be more receptive to change, and highlighted the importance of Chinese medicine theory-based lifestyle change for lasting benefit. Counsellors more often highlighted the importance of the therapeutic relationship, emphasising the need for careful “pacing” such that the process and tools employed were tailored and timed for each individual, depending on the “readiness” to change. Our data is limited to acupuncture practitioners using the principles of traditional Chinese medicine, and counsellors using a humanistic, non-directive and person-centred approach. Conclusions: Long-term change appears to be an important focus within the practices of both acupuncturists and counsellors. To achieve this, practitioners stressed the need for an individualised approach with a focus on root causes
Plans for High Beta Optics in the LHC
ISBN 978-3-95450-115-1 - http://accelconf.web.cern.ch/AccelConf/IPAC2012/papers/moppc007.pdfInternational audienceBased on what has been learned with the first high β* = 90 m operation in 2011, we describe the potential and practical scenarios for reaching very high β* in the LHC in 2012 and beyond. Very high β* optics require dedicated running time and conditions in the LHC. We describe a plan which is optimized to maximize the physics potential in a minimum of dedicated running time
Gauged Fermionic Q-balls
We present a new model for a non-topological soliton (NTS) that contains
interacting fermions, scalar particles and a gauge field. Using a variational
approach, we estimate the energy of the localized configuration, showing that
it can be the lowest energy state of the system for a wide range of parameters.Comment: 5 pages, 2 figures; revised version to appear in Phys. Rev.
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