115 research outputs found

    Stochasticity of comet P/Slaughter-Burnham

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    Three comets are now known to be at or near the 1/1 resonance with Jupiter: P/Slaughter-Burnham, P/Boethin and the newly discovered P/Ge-Wang. Although details of the individual orbits differ, the three comets have very similar dynamical behavior: their orbits show many transitions between the different types of resonant motion (satellite libration, anti-satellite libration, and circulating motion). The stochastic character of such cometary orbits, mainly due to encounters with Jupiter is investigated using Lyapunov Characteristic Indicators. For each comet of the group, we study the influences on the stochasticity of initial eccentricity, inclination, longitude of node, and l-l(sub J) (mean longitude of comet minus mean longitude of Jupiter). We present here our first results for P/Slaughter-Burnham

    New directions for lifelong learning using network technologies

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    Please refer only to original source: Koper, R., Tattersall, C. (2004). New directions for lifelong learning using network technologies. British Journal of Educational Technology, 35 (6), 689-700.The requirements placed on learning technologies to support lifelong learning differ considerably from those placed on technologies to support particular fragments of a learning lifetime. The time scales involved in lifelong learning, together with its multi-institutional and episodic nature are not reflected in today’s mainstream learning technologies and their associated architectures. The article presents an integrated model and architecture to serve as the basis for the realization of networked learning technologies serving the specific needs and characteristics of lifelong learners. The integrative model is called a “Learning Network” (LN) and its requirements and architecture are explored, together with the ways in which its application can help in reducing barriers to lifelong learning

    Interaction Between Convection and Pulsation

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    This article reviews our current understanding of modelling convection dynamics in stars. Several semi-analytical time-dependent convection models have been proposed for pulsating one-dimensional stellar structures with different formulations for how the convective turbulent velocity field couples with the global stellar oscillations. In this review we put emphasis on two, widely used, time-dependent convection formulations for estimating pulsation properties in one-dimensional stellar models. Applications to pulsating stars are presented with results for oscillation properties, such as the effects of convection dynamics on the oscillation frequencies, or the stability of pulsation modes, in classical pulsators and in stars supporting solar-type oscillations.Comment: Invited review article for Living Reviews in Solar Physics. 88 pages, 14 figure

    The diffusion of policy in contexts of practice : flexible delivery in Australian vocational education and training

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    Significant changes have occurred over the last decade within the Australian Vocational Education and Training (VET) system. Not least amongst these has been a shift from a predominantly traditional face-to-face classroom model of programme delivery to more flexible models informed by the needs of clients. To lead this revolution, in 1991 the Australian Commonwealth and State Ministers for Training established the Flexible Delivery Working Party. A series of reports followed that sought to develop a policy framework, including a definition of flexible delivery, and its principles and characteristics. Despite these efforts, project funding and national staff development initiatives, several difficulties have been experienced in the ‘take-up’ of flexible delivery; problems that we argue are related to how the dissemination of innovative practice is conceived. Specifically, the literature and research on the diffusion of innovations points to the efficacy of informal social networks ‘in which individuals adopt the new idea as a result of talking with other individuals who have already adopted it’ (Valente, 1995, p. ix). Following a discussion of these issues, the article concludes by arguing the need for research of innovative practice transfer within VET in Australia, using qualitative case study in order to develop an in-depth and rich description of the process, and facilitate greater understanding of how it works in practice

    Asteroseismology and Interferometry

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    Asteroseismology provides us with a unique opportunity to improve our understanding of stellar structure and evolution. Recent developments, including the first systematic studies of solar-like pulsators, have boosted the impact of this field of research within Astrophysics and have led to a significant increase in the size of the research community. In the present paper we start by reviewing the basic observational and theoretical properties of classical and solar-like pulsators and present results from some of the most recent and outstanding studies of these stars. We centre our review on those classes of pulsators for which interferometric studies are expected to provide a significant input. We discuss current limitations to asteroseismic studies, including difficulties in mode identification and in the accurate determination of global parameters of pulsating stars, and, after a brief review of those aspects of interferometry that are most relevant in this context, anticipate how interferometric observations may contribute to overcome these limitations. Moreover, we present results of recent pilot studies of pulsating stars involving both asteroseismic and interferometric constraints and look into the future, summarizing ongoing efforts concerning the development of future instruments and satellite missions which are expected to have an impact in this field of research.Comment: Version as published in The Astronomy and Astrophysics Review, Volume 14, Issue 3-4, pp. 217-36

    Power spectra of velocity fluctuations in plages

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    Spatial power spectral densities of velocities in plages were compared with velocity power spectra of the quiet photosphere. The comparison suggests that photospheric oscillations are not gravity waves.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43735/1/11207_2004_Article_BF00154971.pd

    How Can We Improve Oncofertility Care for Patients? A Systematic Scoping Review of Current International Practice and Models of Care

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    © The Author(s) 2018. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. BACKGROUND: Fertility preservation (FP) is an important quality of life issue for cancer survivors of reproductive age. Despite the existence of broad international guidelines, the delivery of oncofertility care, particularly amongst paediatric, adolescent and young adult patients, remains a challenge for healthcare professionals (HCPs). The quality of oncofertility care is variable and the uptake and utilization of FP remains low. Available guidelines fall short in providing adequate detail on how oncofertility models of care (MOC) allow for the real-world application of guidelines by HCPs. OBJECTIVE AND RATIONALE: The aim of this study was to systematically review the literature on the components of oncofertility care as defined by patient and clinician representatives, and identify the barriers, facilitators and challenges, so as to improve the implementation of oncofertility services. SEARCH METHODS: A systematic scoping review was conducted on oncofertility MOC literature published in English between 2007 and 2016, relating to 10 domains of care identified through consumer research: communication, oncofertility decision aids, age-appropriate care, referral pathways, documentation, training, supportive care during treatment, reproductive care after cancer treatment, psychosocial support and ethical practice of oncofertility care. A wide range of electronic databases (CINAHL, Embase, PsycINFO, PubMed, AEIPT, Education Research Complete, ProQuest and VOCED) were searched in order to synthesize the evidence around delivery of oncofertility care. Related citations and reference lists were searched. The review was undertaken following registration (International prospective register of systematic reviews (PROSPERO) registration number CRD42017055837) and guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). OUTCOMES: A total of 846 potentially relevant studies were identified after the removal of duplicates. All titles and abstracts were screened by a single reviewer and the final 147 papers were screened by two reviewers. Ten papers on established MOC were identified amongst the included papers. Data were extracted from each paper and quality scores were then summarized in the oncofertility MOC summary matrix. The results identified a number of themes for improving MOC in each domain, which included: the importance of patients receiving communication that is of a higher quality and in different formats on their fertility risk and FP options; improving provision of oncofertility care in a timely manner; improving access to age-appropriate care; defining the role and scope of practice of all HCPs; and improving communication between different HCPs. Different forms of decision aids were found useful for assisting patients to understand FP options and weigh up choices. WIDER IMPLICATIONS: This analysis identifies core components for delivery of oncofertility MOC. The provision of oncofertility services requires planning to ensure services have safe and reliable referral pathways and that they are age-appropriate and include medical and psychological oncofertility care into the survivorship period. In order for this to happen, collaboration needs to occur between clinicians, allied HCPs and executives within paediatric and adult hospitals, as well as fertility clinics across both public and private services. Training of both cancer and non-cancer HCPs is needed to improve the knowledge of HCPs, the quality of care provided and the confidence of HCPs with these consultations
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