7,108 research outputs found

    Low dielectric fluorinated poly(phenylene ether ketone) film and coating

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    The present invention relates to film and coating materials prepared from novel fluorinated poly(phenylene ether ketones). A fluorinated poly(phenylene ether ketone) is prepared by reacting a bisphenol with 1,1,1,3,3,3 hexafluoro-2,2-bis 4-(4-halobenzoyl) phenyl propane (wherein halo is fluoro or chloro), which is a novel monomer formed as the reaction product of halobenzene (wherein halo is fluoro or chloro) and 1,1,1,3,3,3 hexafluoro-2,2-bis (p-chloro formyl phenyl) propane. Especially beneficial results of this invention are that films and coating materials prepared from the novel fluorinated poly(phenylene ether ketone) are essentially optically transparent/colorless and have a lower dielectric constant than otherwise comparable, commercially available poly(phenylene ether ketones). Moreover, unlike the otherwise comparable commercially available materials, the novel fluorinated poly(phenylene ether ketones) of the present invention can be solution cast or sprayed to produce the films and coatings. Furthermore, the long term thermal stability of the polymers of the present invention is superior to that of the commercially available materials

    Stories as personal coaching philosophy

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    The importance of coaches developing and articulating a personal coaching philosophy which encapsulates their values and beliefs is widely recognised. Yet it is also acknowledged that many coaches resist what appears an abstract task or find it to be of limited use in their day-to-day practice. In this paper we explore the potential of an alternative approach to developing and articulating a personal coaching philosophy: storytelling. Following a discussion of the potential of stories, we present a story written by one coach which expresses her personal philosophy in a way that is firmly rooted in her coaching practice. Storytelling approaches, we suggest, can reveal the connections between abstract/general philosophy and the personal embodied experience of coaching. We reflect on the possibilities and problems of using stories as philosophy and offer some suggestions for how coaches may be supported in developing their coaching philosophy through storytelling

    The Mercury-Redstone project

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    Mercury-Redstone project development history, and contributions to future manned spacecraft design and operatio

    Gibbs Sampling with Low-Power Spiking Digital Neurons

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    Restricted Boltzmann Machines and Deep Belief Networks have been successfully used in a wide variety of applications including image classification and speech recognition. Inference and learning in these algorithms uses a Markov Chain Monte Carlo procedure called Gibbs sampling. A sigmoidal function forms the kernel of this sampler which can be realized from the firing statistics of noisy integrate-and-fire neurons on a neuromorphic VLSI substrate. This paper demonstrates such an implementation on an array of digital spiking neurons with stochastic leak and threshold properties for inference tasks and presents some key performance metrics for such a hardware-based sampler in both the generative and discriminative contexts.Comment: Accepted at ISCAS 201

    The potential for dietary factors to prevent or treat osteoarthritis

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    Osteoarthritis (OA) is a degenerative joint disease for which there are no disease-modifying drugs. It is a leading cause of disability in the UK. Increasing age and obesity are both major risk factors for OA and the health and economic burden of this disease will increase in the future. Focusing on compounds from the habitual diet that may prevent the onset or slow the progression of OA is a strategy that has been under-investigated to date. An approach that relies on dietary modification is clearly attractive in terms of risk/benefit and more likely to be implementable at the population level. However, before undertaking a full clinical trial to examine potential efficacy, detailed molecular studies are required in order to optimise the design. This review focuses on potential dietary factors that may reduce the risk or progression of OA, including micronutrients, fatty acids, flavonoids and other phytochemicals. It therefore ignores data coming from classical inflammatory arthritides and nutraceuticals such as glucosamine and chondroitin. In conclusion, diet offers a route by which the health of the joint can be protected and OA incidence or progression decreased. In a chronic disease, with risk factors increasing in the population and with no pharmaceutical cure, an understanding of this will be crucial

    Positronium production in cryogenic environments

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    We report measurements of positronium (Ps) formation following positron irradiation of mesoporous SiO2 films and Ge(100) single crystals at temperatures ranging from 12–700 K. As both of these materials generate Ps atoms via nonthermal processes, they are able to function as positron-positronium converters at cryogenic temperatures. Our data show that such Ps formation is possibly provided the targets are not compromised by adsorption of residual gas. In the case of SiO2 films, we observe a strong reduction in the Ps formation efficiency following irradiation with UV laser light (λ=243.01 nm) below 250 K, in accordance with previous observations of radiation-induced surface paramagnetic centers. Conversely, Ps emission from Ge is enhanced by irradiation with visible laser light (λ=532 nm) via a photoemission process that persists at cryogenic temperatures. Both mesoporous SiO2 films and Ge crystals were found to produce Ps efficiently in cryogenic environments. Accordingly, these materials are likely to prove useful in several areas of research, including Ps mediated antihydrogen formation conducted in the cold bore of a superconducting magnet, the production of Rydberg Ps for experiments in which the effects of black-body radiation must be minimized, and the utilization of mesoporous structures that have been modified to produce cold Ps atoms

    Relaxation Design of Separable Tube Connectors

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    Design procedure to predict relaxation or time to leakage for separable tube connector

    Using Stories in Coach Education

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    The purpose of this paper is to illustrate how storied representations of research can be used as an effective pedagogical tool in coach education. During a series of continuing professional development seminars for professional golf coaches, we presented our research in the form of stories and poems which were created in an effort to evoke and communicate the lived experiences of elite professional golfers. Following these presentations, we obtained written responses to the stories from 53 experienced coaches who attended the seminars. Analysis of this data revealed three ways in which coaches responded to the stories: (i) questioning; (ii) summarising; and (iii) incorporating. We conclude that these responses illustrate the potential of storied forms of representation to enhance professional development through stimulating reflective practice and increasing understanding of holistic, person-centred approaches to coaching athletes in high-performance sport

    Making mentoring work: The need for rewiring epistemology

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    To help produce expert coaches at both participation and performance levels, a number of governing bodies have established coach mentoring systems. In light of the limited literature on coach mentoring, as well as the risks of superficial treatment by coach education systems, this paper therefore critically discusses the role of the mentor in coach development, the nature of the mentor-mentee relationship and, most specifically, how expertise in the mentee may best be developed. If mentors are to be effective in developing expert coaches then we consequently argue that a focus on personal epistemology is required. On this basis, we present a framework that conceptualizes mentee development on this level through a step by step progression, rather than unrealistic and unachievable leap toward expertise. Finally, we consider the resulting implications for practice and research with respect to one-on-one mentoring, communities of practice, and formal coach education
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