2,778 research outputs found
United Airlines LOFT training
Line oriented training is used in a broader, more generic sense that as a specific program under FAR 12.1409 and AC 120-35. A company policy was adopted more than twenty years ago requiring that all pilot checks and recurrent training be conducted with a full crew occupying the seats they occupy on the line. Permission was obtained to reschedule the hours for recurrent proficiency training to include one and one-half hours of LOFT flight. The number of emergencies and abnormal procedures which could be undertaken were considered and the introduction of an a occasional incapacitation revealed which person is the most difficult to replace on the widebodies. By using the LOFT concept, every training period can be structured like a typical line flight. The use of LOFT in simulator syllabus development and problems that need to be refined are discussed
Nuclear Magnetic Resonance in Low-Symmetry Superconductors
We consider the nuclear spin-lattice relaxation rate, in
superconductors with accidental nodes. We show that a Hebel-Slichter-like peak
occurs even in the absence of an isotropic component of the superconducting
gap. The logarithmic divergence found in clean, non-interacting models is
controlled by both disorder and electron-electron interactions. However, for
reasonable parameters, neither of these effects removes the peak altogether.Comment: 10 pages, 5 figure
The Resolved Outer Population of NGC6822 with WFPC2
We present F336W (U), F439W (B), F555W (V), and F675W (R) Wide Field
Planetary Camera 2 (WFPC2) photometry of two outer regions of the Local Group
dwarf irregular galaxy NGC6822. The NE region is ~13 arcmin from the galaxy
centre, while the W region lies 10 arcmin out, and within the wispy low surface
brightness outer regions of the galaxy. The fields are not crowded and contain
few NGC 6822 stars. We discuss errors and uncertainties and find that the W
region contains a main sequence that extends to stars of about 2 solar masses,
with an age of about 200 Myr. The NE region has no main sequence or stars
younger than 1 Gyr, but does contain some luminous red stars that are not
matched in the W field. These stars are not clumped in the field. The results
suggest that the W region may be a trace of a tidal event that triggered the
current star-formation in this isolated galaxy.Comment: 12 pages including 2 tables, plus 4 figures (#1 omitted) To appear in
PAS
Challenges and implications of routine depression screening for depression in chronic disease and multimorbidity: a cross sectional study
<b>Background</b> Depression screening in chronic disease is advocated but its impact on routine practice is uncertain. We examine the effects of a programme of incentivised depression screening in chronic disease within a UK primary care setting.<p></p>
<b>Methods and Findings</b> Cross sectional analysis of anonymised, routinely collected data (for 2008-9) from family practices in Scotland serving a population of circa 1.8 million. Patients registered in primary care with at least one of three chronic diseases, coronary heart disease, diabetes and stroke, underwent incentivised depression screening using the Hospital Anxiety and Depression Score (HADS). <p></p>
125143 patients were identified with at least one chronic disease. 10670 (8.5%) were under treatment for depression and exempt from screening. Of the remaining, HADS were recorded for 35537 (31.1%) patients. 7080 (19.9% of screened) had raised HADS (≥8); the majority had indications of mild depression with a HADS between 8 and 10. Over 6 months, 572 (8%) of those with a raised HADS (≥8) were initiated on antidepressants, while 696 (2.4%) patients with a normal HADS (<8) were also initiated on antidepressants (relative risk of antidepressant initiation with raised HADS 3.3 (CI 2.97-3.67), p value <0.0001). Of those with multimorbidity who were screened, 24.3% had a raised HADS (≥8). A raised HADS was more likely in females, socioeconomically deprived, multimorbid or younger (18-44) individuals. Females and 45-64 years old were more likely to receive antidepressants.<p></p>
<b>Limitations</b> â retrospective study of routinely collected data.<p></p>
<b>Conclusions </b> Despite incentivisation, only minority of patients underwent depression screening, suggesting that systematic depression screening in chronic disease can be difficult to achieve in routine practice. Targeting those at greatest risk such as the multimorbid or using simpler screening methods may be more effective. Raised HADS was associated with a higher number of new antidepressant prescriptions which has significant resource implications. The clinical benefits of such screening remain uncertain and merit investigation
Foveal target repetitions reduce crowding
Crowding is the limitation of peripheral vision by clutter. Objects that are easily identified when presented in isolation are hard to identify when presented flanked by similar close-by objects. It is often assumed that the signal of a crowded target is irretrievably lost because it is combined with the signals of the flankers. Here, we asked whether a target signal can be enhanced (or retrieved) by items presented far outside the crowding region. We investigated whether remote items matching a peripheral, crowded target enhanced discrimination compared to remote items not matching the target. In Experiment 1, we presented the remote item at different locations in the visual field and found that, when presented in the fovea, a matching remote item improved target discrimination compared to a nonmatching remote item. In Experiment 2, we varied stimulus onset asynchronies between target and remote items and found a strong effect when the remote item was presented simultaneously with the target. The effect diminished (or was absent) with increasing temporal separation. In Experiment 3, we asked whether semantic knowledge of a target was sufficient to improve target discrimination and found that this was not the case. We conclude that crowded target signals are not irretrievably lost. Rather, their accurate recognition is facilitated in the presence of remote items that match the target. We suggest that long-range grouping mechanisms underlie this "uncrowding" effect
High-resolution photoelectron spectroscopy of linear â bent polyatomic photodetachment transitions: The electron affinity of CSâ
A combination of high-resolution velocity-map-imaging photoelectron spectroscopy and isotopic
substitution is used to show that precise electron affinities can be obtained from polyatomic photodetachment
spectra, even for cases involving significant changes in equilibrium geometry between
the molecular neutral and anion.This research was supported by the Australian Research
Council (Grant Nos. DP0666267 and DP0880850)
Predicting cortical bone adaptation to axial loading in the mouse tibia
The development of predictive mathematical models can contribute to a deeper understanding of the specific stages of bone mechanobiology and the process by which bone adapts to mechanical forces. The objective of this work was to predict, with spatial accuracy, cortical bone adaptation to mechanical load, in order to better understand the mechanical cues that might be driving adaptation. The axial tibial loading model was used to trigger cortical bone adaptation in C57BL/6 mice and provide relevant biological and biomechanical information. A method for mapping cortical thickness in the mouse tibia diaphysis was developed, allowing for a thorough spatial description of where bone adaptation occurs. Poroelastic finite-element (FE) models were used to determine the structural response of the tibia upon axial loading and interstitial fluid velocity as the mechanical stimulus. FE models were coupled with mechanobiological governing equations, which accounted for non-static loads and assumed that bone responds instantly to local mechanical cues in an onâoff manner. The presented formulation was able to simulate the areas of adaptation and accurately reproduce the distributions of cortical thickening observed in the experimental data with a statistically significant positive correlation (Kendall's Ï rank coefficient Ï = 0.51, p < 0.001). This work demonstrates that computational models can spatially predict cortical bone mechanoadaptation to a time variant stimulus. Such models could be used in the design of more efficient loading protocols and drug therapies that target the relevant physiological mechanisms
Cylindrical, periodic surface lattice â theory, dispersion analysis, and experiment
A two-dimensional surface lattice of cylindrical topology obtained via perturbing the inner surface of a cylinder is considered. Periodic perturbations of the surface lead to observation of high-impedance, dielectric-like media and resonant coupling of surface and non-propagating volume fields. This allows synthesis of tailored-for-purpose "coating" material with dispersion suitable, for instance, to mediate a Cherenkov type interaction. An analytical model of the lattice is discussed and coupled-wave equations are derived. Variations of the lattice dispersive properties with variation of parameters are shown, illustrating the tailoring of the structure's electromagnetic properties. Experimental results are presented showing agreement with the theoretical model
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