661 research outputs found
On the regular-geometric-figure solution to the N-body problem
The regular-geometric-figure solution to the -body problem is presented in
a very simple way. The Newtonian formalism is used without resorting to a more
involved rotating coordinate system. Those configurations occur for other kinds
of interactions beyond the gravitational ones for some special values of the
parameters of the forces. For the harmonic oscillator, in particular, it is
shown that the -body problem is reduced to one-body problems.Comment: To appear in Eur. J. Phys. (5 pages
Undergraduate student experience in dental service delivery in rural South Australia: An analysis of costs and benefits
The document attached has been archived with permission from the Australian Dental Association. An external link to the publisher’s copy is included.Background: Rural experience for dental students can provide valuable clinical education, change attitudes to rural practice, and make a valuable contribution to clinical service provision. The aim of this paper is to assess the costs and benefits of service delivery by students through rural training programmes. Methods: Groups of two students worked in the public dental clinics in adjacent rural centres where there had been long-term difficulties in recruiting staff. The costs and benefits of the programme were assessed by the impact on waiting lists, the total cost per patient of a course of care and by the marginal cost of adding service provision by students to existing arrangements. Results: The total costs of emergency and complete treatment provided by students were greater than the costs of treatment provided by public-sector dentists but less than the costs of private providers treating public patients. However, the value of services were greater when care was provided by students or private providers and the marginal cost of students providing services was 50-70 per cent of the cost of care provided by public dentists. Conclusion: This assessment suggests that the service benefits achieved compliment the primary objective of influencing the attitude of students to rural practice.L Richards, B Symon, D Burrow, A Chartier, G Misan and D Wilkinso
Effect of a consultation teaching behaviour modification on sleep performance in infants: a randomised controlled trial
The document attached has been archived with permission from the editor of the Medical Journal of Australia (09 January 2008). An external link to the publisher’s copy is included.Objective: To evaluate the effect of a behaviour modification program, taught to parents in a single visit to a trained nurse, in improving sleep performance in newborn infants. Design: Randomised controlled trial. Setting and participants: 268 families with normal newborn infants in the community, recruited between October 1996 and March 1997 from birth notices published in a South Australian daily newspaper. Intervention: A 45-minute consultation with a nurse 2–3 weeks after the birth, including a tutorial discussion on normal sleep patterns in newborn infants, supported by retained written material and, for infants with weight gain < 30 g daily, referral to their usual postnatal care provider. Main outcome measures: Hours of daytime sleep (0600–1800), night sleep (1800–0600) and total sleep per 24 h; and number of daily records with total sleep ≥ 15 h per 24 h, assessed by 7-day sleep diary at ages 6 and 12 weeks. Results: 268 families returned at least one sleep diary (137/171 intervention, 131/175 control), recording 3273 days. Two intervention infants were referred for low weight gain. Total sleep time was 15 h or more per 24 h on 62% of recorded days in the intervention group, compared with 36% in the control group (P < 0.001). At 6 weeks of age, intervention infants slept a mean 1.3 h per day more than control infants (95% CI, 0.95–1.65), comprising a mean 0.5 h more night sleep (95% CI, 0.32–0.69) and 0.8 h more daytime sleep (95% CI, 0.56–1.07). At 12 weeks, intervention infants slept a mean 1.2 h per day more (95% CI, 0.94–2.14), comprising 0.64 h more night sleep (95% CI, 0.19–0.89) and 0.58 h more daytime sleep (95% CI, 0.39–1.03). There was no significant difference in crying time between the groups. Conclusions: A single consultation supported by written material in the first 3 weeks of a child’s life improves sleep performance at 6 weeks of age. This improvement is maintained at 3 months.Brian G Symon, John E Marley, A James Martin and Emily R Norma
Resonance in Bose-Einstein condensate oscillation from a periodic variation in scattering length
Using the explicit numerical solution of the axially-symmetric
Gross-Pitaevskii equation we study the oscillation of the Bose-Einstein
condensate induced by a periodic variation in the atomic scattering length .
When the frequency of oscillation of is an even multiple of the radial or
axial trap frequency, respectively, the radial or axial oscillation of the
condensate exhibits resonance with novel feature. In this nonlinear problem
without damping, at resonance in the steady state the amplitude of oscillation
passes through maximum and minimum. Such growth and decay cycle of the
amplitude may keep on repeating. Similar behavior is also observed in a
rotating Bose-Einstein condensate.Comment: 14 REVTEX4 pages, 18 PS figures, final version Accepted in Journal of
Physics
Implementing digital resources for clinicians' and patients' varying needs.
This paper presents an overview of several evidence-based medicine and patient information studies conducted across the UK health service over a 4 year period, investigating clinicians', managers', and patients' perceptions of digital resources (primarily digital libraries) in hospitals, Primary Care Trusts, NHS Direct (patient call centre) and patient groups. In-depth interviews and focus groups are analysed using grounded theory methodologies and through content analysis used to produce quantitative finding. The perceived impacts of three different methods employed for delivering health informatics are presented. The findings highlight some generic issues relevant for health informatics in the UK health sector as well as some specific issues for medical digital libraries. This paper reviews in more detail the issues of medical technology implementation (traditional implementation, on the wards, and intermediaries within in communities). A breakdown of the clinicians' and patients' information journey (information initiation, facilitation and interpretation) is also presented with regard to medical digital libraries and online resources. Broad guidelines derived from these findings are provided for health-informatics deployment
Tidal Forces in Reissner-Nordström Spacetimes
We analyze the tidal forces produced in the spacetime of Reissner-Nordstr\"om black holes. We point out that the radial component of the tidal force changes sign just outside the event horizon if the charge-to-mass ratio is close to unlike in Schwarzschild spacetime of uncharged black holes, and that the angular component changes sign between the outer and inner horizons. We solve the geodesic deviation equations for radially falling bodies towards the charged black hole. We find, for example, that the radial component of the geodesic deviation vector starts decreasing inside the event horizon unlike in the Schwarzschild case
Integration of a nationally procured electronic health record system into user work practices
BACKGROUND: Evidence suggests that many small- and medium-scale Electronic Health Record (EHR) implementations encounter problems, these often stemming from users' difficulties in accommodating the new technology into their work practices. There is the possibility that these challenges may be exacerbated in the context of the larger-scale, more standardised, implementation strategies now being pursued as part of major national modernisation initiatives. We sought to understand how England's centrally procured and delivered EHR software was integrated within the work practices of users in selected secondary and specialist care settings. METHODS: We conducted a qualitative longitudinal case study-based investigation drawing on sociotechnical theory in three purposefully selected sites implementing early functionality of a nationally procured EHR system. The complete dataset comprised semi-structured interview data from a total of 66 different participants, 38.5 hours of non-participant observation of use of the software in context, accompanying researcher field notes, and hospital documents (including project initiation and lessons learnt reports). Transcribed data were analysed thematically using a combination of deductive and inductive approaches, and drawing on NVivo8 software to facilitate coding. RESULTS: The nationally led "top-down" implementation and the associated focus on interoperability limited the opportunity to customise software to local needs. Lack of system usability led users to employ a range of workarounds unanticipated by management to compensate for the perceived shortcomings of the system. These had a number of knock-on effects relating to the nature of collaborative work, patterns of communication, the timeliness and availability of records (including paper) and the ability for hospital management to monitor organisational performance. CONCLUSIONS: This work has highlighted the importance of addressing potentially adverse unintended consequences of workarounds associated with the introduction of EHRs. This can be achieved with customisation, which is inevitably somewhat restricted in the context of attempts to implement national solutions. The tensions and potential trade-offs between achieving large-scale interoperability and local requirements is likely to be the subject of continuous debate in England and beyond with no easy answers in sight
Reducing postnatal depression, anxiety and stress using an infant sleep intervention
Extent: 6p.Objective: To examine the psychological well-being of mothers following participation in a behavioural modification programme previously shown to improve infant sleep. Design, setting and participants: A 45 min consultation with either a general practitioner (GP) or trained nurse providing verbal and written information describing sleep physiology in infants and strategies to improve infant sleep. Eighty mothers of infants 6−12 months of age with established infant sleep problems at a single general practice, Adelaide, South Australia. Main outcome measures: The Depression Anxiety Stress Scale 21 (DASS21) immediately prior to the first consultation and again at follow-up approximately 3 weeks later. The number of infant nocturnal awakenings requiring parental support was also reported by mothers on both occasions. Results: All measures of maternal well-being and infant nocturnal awakenings improved significantly. The mean number of maximum nocturnal awakenings decreased from 5.0 to 0.5 (mean difference 4.4, 95% CI 3.4 to 5.5). All measures of DASS21 improved significantly. The mean total DASS21 decreased from 29.1 to 14.9 (mean decrease 14.2, 95% CI 10.2 to 18.2); mean depression decreased from 7.9 to 2.8 (mean difference 5.2, 95% CI 3.7 to 6.7); mean anxiety decreased from 4.6 to 2.6 (mean difference 2.0, 95% CI 0.7 to 3.2); mean stress decreased from 16.6 to 9.5 (mean difference 7.0, 95% CI 5.1 to 9.0). The proportion of mothers assessed as having any degree of depression decreased by 85% from 26/80 (32.5%) to 4/80 (5%). Conclusions: The number of nocturnal awakenings requiring parental support among infants aged 6−12 months significantly decreased following a single consultation on infant sleep physiology and teaching behavioural strategies to improve sleep. Significant improvements in maternal stress, anxiety and depression were also observed.Brian Symon, Michael Bammann, Georgina Crichton, Chris Lowings, James Tucso
Rhizoclonium hieroglyphicum and Recycled Papers as Materials for Handcrafted Papermaking
The study explored the usage of Rhizoclonium hieroglyphicum and recycled papers as materials for handcrafted paper. The Rhizoclonium hieroglyphicum was mixed with 25%, 50%, and 75% wastepaper with three treatments of different material ratios formed following the same procedure. Each treatment was tested in terms of grammage, opacity, microscopic analysis, and tensile strength, with each test having ten trials except the oil absorbency and thickness test. Algae were mixed with 1.5% NaOH and cooked for 30 minutes at 95 degrees Celsius then 10 grams of calcium carbonate for every 100 grams of the pulp mixture. After various tests of the algae paper, the results show that the product composed of 75% algae and 25% waste copy paper has a higher value in terms of the tests recommended by the Department of Science and Technology (DOST). After analyzing the data of the tests to determine the viability and quality of the treatments, as well as taking their data and results, and having a statistical analysis among the three treatments, it shows the effectiveness of using Rhizoclonium hieroglyphicum as an alternative material for paper
Prenatal exposures and exposomics of asthma
This review examines the causal investigation of preclinical development of childhood asthma using exposomic tools. We examine the current state of knowledge regarding early-life exposure to non-biogenic indoor air pollution and the developmental modulation of the immune system. We examine how metabolomics technologies could aid not only in the biomarker identification of a particular asthma phenotype, but also the mechanisms underlying the immunopathologic process. Within such a framework, we propose alternate components of exposomic investigation of asthma in which, the exposome represents a reiterative investigative process of targeted biomarker identification, validation through computational systems biology and physical sampling of environmental medi
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