398 research outputs found
Sport medicine and sport science practitioners' experiences of organizational change
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Despite the emergence of and widespread uptake of a growing range of medical and scientific professions in elite sport, such environs present a volatile professional domain characterized by change and unprecedentedly high turnover of personnel. This study explored sport medicine and science practitioners' experiences of organizational change using a longitudinal design over a 2-year period. Specifically, data were collected in three temporally defined phases via 49 semi-structured interviews with 20 sport medics and scientists employed by three organizations competing in the top tiers of English football and cricket. The findings indicated that change occurred over four distinct stages; anticipation and uncertainty, upheaval and realization, integration and experimentation, normalization and learning. Moreover, these data highlight salient emotional, behavioral, and attitudinal experiences of medics and scientists, the existence of poor employment practices, and direct and indirect implications for on-field performance following organizational change. The findings are discussed in line with advances to extant change theory and applied implications for prospective sport medics and scientists, sport organizations, and professional bodies responsible for the training and development of neophyte practitioners
IACT observations of gamma-ray bursts: prospects for the Cherenkov Telescope Array
Gamma rays at rest frame energies as high as 90 GeV have been reported from
gamma-ray bursts (GRBs) by the Fermi Large Area Telescope (LAT). There is
considerable hope that a confirmed GRB detection will be possible with the
upcoming Cherenkov Telescope Array (CTA), which will have a larger effective
area and better low-energy sensitivity than current-generation imaging
atmospheric Cherenkov telescopes (IACTs). To estimate the likelihood of such a
detection, we have developed a phenomenological model for GRB emission between
1 GeV and 1 TeV that is motivated by the high-energy GRB detections of
Fermi-LAT, and allows us to extrapolate the statistics of GRBs seen by lower
energy instruments such as the Swift-BAT and BATSE on the Compton Gamma-ray
Observatory. We show a number of statistics for detected GRBs, and describe how
the detectability of GRBs with CTA could vary based on a number of parameters,
such as the typical observation delay between the burst onset and the start of
ground observations. We also consider the possibility of using GBM on Fermi as
a finder of GRBs for rapid ground follow-up. While the uncertainty of GBM
localization is problematic, the small field-of-view for IACTs can potentially
be overcome by scanning over the GBM error region. Overall, our results
indicate that CTA should be able to detect one GRB every 20 to 30 months with
our baseline instrument model, assuming consistently rapid pursuit of GRB
alerts, and provided that spectral breaks below 100 GeV are not a common
feature of the bright GRB population. With a more optimistic instrument model,
the detection rate can be as high as 1 to 2 GRBs per year.Comment: 28 pages, 24 figures, 4 tables, submitted to Experimental Astronom
Emotional labor and professional practice in sports medicine and science
The aim of the present study was to explore how sport medicine and science practitioners manage their emotions through emotional labor when engaging in professional practice in elite sport. To address the research aim a semi-structured interview design was adopted. Specifically, eighteen professional sport medicine and science staff provided interviews. The sample comprised sport and exercise psychologists (n = 6), strength and conditioning coaches (n = 5), physiotherapists (n = 5), one sports doctor and one generic sport scientist. Following a process of thematic analysis, the results were organized into the following overarching themes: (a) factors influencing emotional labor enactment, (b) emotional labor enactment and, (c) professional and personal outcomes. The findings provide a novel contribution to understanding the professional demands faced by practitioners, and are discussed in relation to the development of professional competencies and the welfare and performance of sport medics and scientists
Star Formation in Galaxies Along the Hubble Sequence
Observations of star formation rates (SFRs) in galaxies provide vital clues
to the physical nature of the Hubble sequence, and are key probes of the
evolutionary properties of galaxies. The focus of this review is on the broad
patterns in the star formation properties of galaxies along the Hubble
sequence, and their implications for understanding galaxy evolution and the
physical processes that drive the evolution. Star formation in the disks and
nuclear regions of galaxies are reviewed separately, then discussed within a
common interpretive framework. The diagnostic methods used to measure SFRs are
also reviewed, and a self-consistent set of SFR calibrations is presented as an
aid to workers in the field.Comment: 41 pages, with 9 figures. To appear in Volume 36 of the Annual Review
of Astronomy and Astrophysic
The effect of intervertebral cartilage on neutral posture and range of motion in the necks of sauropod dinosaurs
The necks of sauropod dinosaurs were a key factor in their evolution. The habitual posture and range of motion of these necks has been controversial, and computer-aided studies have argued for an obligatory sub-horizontal pose. However, such studies are compromised by their failure to take into account the important role of intervertebral cartilage. This cartilage takes very different forms in different animals. Mammals and crocodilians have intervertebral discs, while birds have synovial joints in their necks. The form and thickness of cartilage varies significantly even among closely related taxa. We cannot yet tell whether the neck joints of sauropods more closely resembled those of birds or mammals. Inspection of CT scans showed cartilage:bone ratios of 4.5% for Sauroposeidon and about 20% and 15% for two juvenile Apatosaurus individuals. In extant animals, this ratio varied from 2.59% for the rhea to 24% for a juvenile giraffe. It is not yet possible to disentangle ontogenetic and taxonomic signals, but mammal cartilage is generally three times as thick as that of birds. Our most detailed work, on a turkey, yielded a cartilage:bone ratio of 4.56%. Articular cartilage also added 11% to the length of the turkey's zygapophyseal facets. Simple image manipulation suggests that incorporating 4.56% of neck cartilage into an intervertebral joint of a turkey raises neutral posture by 15°. If this were also true of sauropods, the true neutral pose of the neck would be much higher than has been depicted. An additional 11% of zygapophyseal facet length translates to 11% more range of motion at each joint. More precise quantitative results must await detailed modelling. In summary, including cartilage in our models of sauropod necks shows that they were longer, more elevated and more flexible than previously recognised
Marr-Hildreth Enhancement of NDE Images
Previous publications [1–5] have demonstrated the usefulness of digital image enhancement techniques for improving visual detection and resolution of features in NDE images. Many of the techniques are high-pass spatial domain convolution filters [6] which are used to enhance the appearance of edges by removing blur. Two of the major advantages of the more popular edge enhancement operators are their ease of implementation and their rapidity of execution [7]. This makes them very useful for rapid “screening” of images. Their major disadvantages are that they emphasize “noise” as well as edges, and some are directionally dependent operators which tend to suppress features that are not aligned in the “preferred” direction
Access to primary care for socio-economically disadvantaged older people in rural areas: exploring realist theory using structural equation modelling in a linked dataset
Background: Realist approaches seek to answer questions such as ‘how?’, ‘why?’, ‘for whom?’, ‘in what circumstances?’ and ‘to what extent?’ interventions ‘work’ using context-mechanism-outcome (CMO) configurations. Quantitative methods are not well-established in realist approaches, but structural equation modelling (SEM) may be useful to explore CMO configurations. Our aim was to assess the feasibility and appropriateness of SEM to explore CMO configurations and, if appropriate, make recommendations based on our access to primary care research. Our specific objectives were to map variables from two large population datasets to CMO configurations from our realist review looking at access to primary care, generate latent variables where needed, and use SEM to quantitatively test the CMO configurations. Methods: A linked dataset was created by merging individual patient data from the English Longitudinal Study of Ageing and practice data from the GP Patient Survey. Patients registered in rural practices and who were in the highest deprivation tertile were included. Three latent variables were defined using confirmatory factor analysis. SEM was used to explore the nine full CMOs. All models were estimated using robust maximum likelihoods and accounted for clustering at practice level. Ordinal variables were treated as continuous to ensure convergence. Results: We successfully explored our CMO configurations, but analysis was limited because of data availability. Two hundred seventy-six participants were included. We found a statistically significant direct (context to outcome) or indirect effect (context to outcome via mechanism) for two of nine CMOs. The strongest association was between ‘ease of getting through to the surgery’ and ‘being able to get an appointment’ with an indirect mediated effect through convenience (proportion of the indirect effect of the total was 21%). Healthcare experience was not directly associated with getting an appointment, but there was a statistically significant indirect effect through convenience (53% mediated effect). Model fit indices showed adequate fit. Conclusions: SEM allowed quantification of CMO configurations and could complement other qualitative and quantitative techniques in realist evaluations to support inferences about strengths of relationships. Future research exploring CMO configurations with SEM should aim to collect, preferably continuous, primary data
The stellar halo of the Galaxy
Stellar halos may hold some of the best preserved fossils of the formation
history of galaxies. They are a natural product of the merging processes that
probably take place during the assembly of a galaxy, and hence may well be the
most ubiquitous component of galaxies, independently of their Hubble type. This
review focuses on our current understanding of the spatial structure, the
kinematics and chemistry of halo stars in the Milky Way. In recent years, we
have experienced a change in paradigm thanks to the discovery of large amounts
of substructure, especially in the outer halo. I discuss the implications of
the currently available observational constraints and fold them into several
possible formation scenarios. Unraveling the formation of the Galactic halo
will be possible in the near future through a combination of large wide field
photometric and spectroscopic surveys, and especially in the era of Gaia.Comment: 46 pages, 16 figures. References updated and some minor changes.
Full-resolution version available at
http://www.astro.rug.nl/~ahelmi/stellar-halo-review.pd
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