1,436 research outputs found
Athletic injury care training in high school coaches
The purpose of this qualitative study was to understand
the client and occupational therapist experiences of a
mental health group. A secondary aim was to explore the
extent to which this group seemed to have reflected a
client-centred approach. The topic emerged from personal
and professional issues related to the therapist as teacher
and to inconsistencies in practice with the profession's
client-centred philosophy. This philosophy, the study's
frame of reference, was established in terms of themes
related to the client-therapist relationship and to client
values. Typical practice was illustrated through an
extensive literature review. Structured didacticexperiential
methods aiming toward skill development were
predominant.
The interpretive sciences and, to a lesser extent, the
critical sciences directed the methodology. An ongoing
support group at a community mental health clinic was
selected as the focus of the study; the occupational
therapist leader and three members became the key
participants. A series of conversational interviews, the
. core method of data collection, was supplemented by
observation, document review, further interviews, and
fieldnotes. Transcriptions of conversations were returned
to participants for verification and for further reflection Analysis primarily consisted of coding and organizing
data according to emerging themes. The participants'
experiences of group, presented as narrative stories within
a group session vignette, were also returned to
participants. There was a common understanding of the
group's structure and the importance of having "air time"
within the group; however, differences in perceptions of
such things as the importance of the group in members' lives
were noted. All members valued the therapeutic aspects of
group, the role of group as weekly activity and, to a lesser
extent, the learning that came from group. The researcher's
perspective provided a critique of the group experience from
a client-centred perspective. Some areas of consistency
with client-centred practice were noted (e.g., therapist
attitudes); however the group seemed to function far from a
client-centred ideal. Members held little authority in a
-relationship dominated by the leaders, and leader agendas
rather than member values controlled the session. Possible
reasons for this discrepancy ranging from past health care
encounters through to co-leader discord emerged.
The actual and potential significance of this study was
discussed according to many areas of implications: to OT
practice, especially client-centred group practice, to
theory development, to further areas of research and
methodology considerations, to people involved in the group
and to my personal growth and development
Human Flight to Lunar and Beyond - Re-Learning Operations Paradigms
For the first time since the Apollo era, NASA is planning on sending astronauts on flights beyond Low-Earth Orbit (LEO). The Human Space Flight (HSF) program started with a successful initial flight in Earth orbit, in December 2014. The program will continue with two Exploration Missions (EM) to Lunar orbit: EM-1 will be unmanned and EM-2, carrying astronauts, will follow. NASA established a multi-center team to address the communications, and related navigation, needs. This paper will focus on the lessons learned in the team, planning for the missions' parts that are beyond Earth orbit. Many of these lessons had to be re-learned, as the HSF program after operated for many years in Earth orbit. Fortunately, the experience base from tracking robotic missions in deep space by the Deep Space Network (DSN) and close interaction with the HSF community to understand the unique needs (e.g. 2-way voice) resulted in a ConOps that leverages of both the deep space robotic and the Human LEO experiences. Several examples will be used to highlight the unique operational needs for HSF missions beyond Earth Orbit, including: - Navigation. At LEO, HSF missions can rely on Global Positioning System (GPS) devices for orbit determination. For Lunar-and-beyond HSF missions, techniques such as precision 2-way and 3-way Doppler and ranging, Delta-Difference-of-range, and eventually on-board navigation will be used. - Impact of latency - the delay associated with Round-Trip-Light-Time (RTLT). Imagine trying to have a 2-way discussion (audio or video) with an astronaut, with a 2-3 sec delay inserted (for Lunar distances) or 20 minutes delay (for Mars distances). - Balanced communications link. For robotic missions, there has been a heavy emphasis on the downlink data rates, bringing back science data from the instruments on-board the spacecraft. Uplink data rates were of secondary importance, used to send commands to the spacecraft. The ratio of downlink-to-uplink data rates was often 10:1 or more. For HSF, rates for uplink and downlink, at least for high-quality video, need to be similar
Human Flight to Lunar and Beyond - Re-Learning Operations Paradigms
For the first time since the Apollo era, NASA is planning on sending astronauts on flights beyond LEO. The Human Space Flight (HSF) program started with a successful initial flight in Earth orbit, in December 2014. The program will continue with two Exploration Missions (EM): EM-1 will be unmanned and EM-2, carrying astronauts, will follow. NASA established a multi-center team to address the communications, and related tacking/navigation needs. This paper will focus on the lessons learned by the team designing the architecture and operations for the missions. Many of these Beyond Earth Orbit lessons had to be re-learned, as the HSF program has operated for many years in Earth orbit. Unlike the Apollo missions that were largely tracked by a dedicated ground network, the HSF planned missions will be tracked (at distances beyond GEO) by the DSN, a network that mostly serves robotic missions. There have been surprising challenges to the DSN as unique modern human spaceflight needs stretch the experience base beyond that of tracking robotic missions in deep space. Close interaction between the DSN and the HSF community to understand the unique needs (e.g. 2-way voice) resulted in a Concept of Operations (ConOps) that leverages both the deep space robotic and the Human LEO experiences. Several examples will be used to highlight the unique challenges the team faced in establishing the communications and tracking capabilities for HSF missions beyond Earth Orbit, including: Navigation. At LEO, HSF missions can rely on GPS devices for orbit determination. For Lunar-and-beyond HSF missions, techniques such as precision 2-way and 3-way Doppler and ranging, Delta-Difference-of-range, and eventually possibly on-board navigation will be used. At the same time, HSF presents a challenge to navigators, beyond those presented by robotic missions - navigating a dynamic/"noisy" spacecraft. Impact of latency - the delay associated with Round-Trip-Light-Time (RTLT). Imagine trying to have a 2-way discussion (audio or video) with an astronaut, with a 2-3 sec or more delay inserted (for lunar distances) or 20 minutes delay (for Mars distances). Balanced communications link. For robotic missions, there has been a heavy emphasis on higher downlink data rates, e.g. bringing back science data. Higher uplink data rates were of secondary importance, as uplink was used only to send commands (and occasionally small files) to the spacecraft. The ratio of downlink-to-uplink data rates was often 10:1 or more. For HSF, a continuous forward link is established and rates for uplink and downlink are more similar
Borosilicate glass potentials for radiation damage simulations
Three borosilicate glass (SiO2-B2O3) fixed charge potentials from the literature are compared (Delaye and Ghaleb, 1996; Kieu et al., 2011; Rushton, 2006) and their suitability for use in simulations of radiation damage is assessed.For a range of densities, we generate glass structures by quenching at 5×1012 K/s using constant volume Molecular Dynamics. In each case, the bond lengths, mean bond angles, bulk modulus, melting point and displacement energy thresholds are calculated, and where possible compared to experimental data. Whereas the bond lengths and mean bond angles are reasonably well predicted, we find that the potentials predict melting temperatures, bulk moduli and densities that are higher than experimental data.The displacement energy thresholds are generally lower than those for ionic crystalline materials, but show a wider spread of values. However, the barriers for atomic rearrangements, after atoms have been displaced in the equilibrium structures, are very high. This indicates, that the radiation damage produced in the ballistic phase of a collision cascade, is likely to persist for extended time scales. This is in contrast to crystals, where interstitials and vacancies can diffuse rapidly between successive radiation events
Iron phosphate glasses: structure determination and displacement energy thresholds, using a fixed charge potential model
Iron phosphate glass is a versatile matrix for the immobilisation of various radioactive elements found in high-level nuclear waste (HLW). Quenched glass structures of iron phosphate glasses with Fe/P ratios of 0.33, 0.67 and 0.75 and with a composition of 40 mol% Fe2O3 and 60 mol% P2O5, with 4% and 17% Fe2 + ion concentrations were generated using molecular dynamics and the threshold displacement energies calculated. In the minimum energy structures, we found that in nearly all cases the P atoms were 4-fold coordinated. The potential energy per atom increased with increasing concentration of Fe2 + ions with similar Fe/P ratio, suggesting that decreasing the Fe2 + content is a stabilising factor. The average bond distances between Fe2 +-O, Fe3 +-O, P-O and O-O were calculated as 2.12, 1.88, 1.5 and 2.5 Å respectively. The threshold displacement energy (Ed) was found to be dependent upon the ion specie, less for Fe2 + ions compared to Fe3 + ions, and was overall slightly lower than that determined for borosilicate glass
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