3,365 research outputs found

    The determination of the direction of the optic axis of uniaxial crystalline materials

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    The birefringence of crystalline substances in general, and of sapphire in particular, is described. A test is described whose purpose is to determine the direction of the optic axis of a cylindrically machined single crystal of sapphire. This test was performed on the NASA Lewis sapphire cylinder and it was found that the optic axis made an angle of 18 deg with the axis of symmetry of the cylinder

    Impact of Marine Locomotion Constraints on a Bio-inspired Aerial-Aquatic Wing:Experimental Performance Verification

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    This paper describes the design, fabrication, experimental testing and performance optimization of the morphology of a flapping wing for use on a robot capable of aerial and aquatic modes of locomotion. The focus of the optimization studies is that of wing design for aquatic propulsion. Inspiration for the research stems from numerous avian species which use a flapping wing for the dual purpose of locomotion (propulsion) in both air and water. The main aim of this research is to determine optimal kinematic parameters for marine locomotion that maximize nondimensionalized performance measures (e.g., propulsive efficiency), derived from analysis of avian wing morphing mechanisms that balance competing demands of both aerial and aquatic movement. Optimization of the kinematic parameters enables the direct comparison between outstretched (aerial) and retracted (aquatic) wing morphologies and permits trade-off studies in the design space for future robotic vehicles. Static foils representing the wing in both an extended and retracted orientation have been manufactured and subsequently subjected to testing over a range of kinematics. Details of the purpose built 2 degree-of-freedom (dof) flapping mechanism are presented. The gathered results enable validation of previously developed numerical models as well as quantifying achievable performance measures. This research focuses on the mechanical propulsive efficiencies and thrust coefficients as key performance measures whilst simultaneously considering the required mechanical input torques and the associated thrust produced.</jats:p

    Protocol for a national monthly survey of alcohol use in England with 6-month follow-up: 'The Alcohol Toolkit Study'.

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    Timely tracking of national patterns of alcohol consumption is needed to inform and evaluate strategies and policies aimed at reducing alcohol-related harm. Between 2014 until at least 2017, the Alcohol Toolkit Study (ATS) will provide such tracking data and link these with policy changes and campaigns. By virtue of its connection with the 'Smoking Toolkit Study' (STS), links will also be examined between alcohol and smoking-related behaviour

    Development and implementation of the Bachelor of Nursing (Conversion) course in Vanuatu.

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    CONTEXT: Vanuatu, a Pacific Island nation in the Western Pacific region, has to date educated its nurses by diploma program. Research evidence in developed countries has consistently shown that nurses educated by bachelor degree improve patient health outcomes and reduce hospital length of stay. In seeking to improve health outcomes, the Vanuatu Ministry of Health decided to introduce a new Bachelor of Nursing degree to provide a skilled, safe nursing workforce for the provision of health care to its peoples{1-3}. The curriculum for this degree was to be developed by Ni-Vanuatu nurse educators with the collaboration of educators from the WHO Collaborating Centre, University of Technology Sydney. However, it was first necessary to upgrade (from diploma to bachelor level) the qualifications of teachers and senior nursing practitioners who would lead the new degree course by introducing a Bachelor of Nursing (Conversion) course. ISSUES: In order to design and implement a Bachelor of Nursing (Conversion) course that would be relevant for the educational and healthcare context in Vanuatu and that would meet qualification requirements of the local regulatory bodies, it was essential to build collaborative relationships with key stakeholders in Vanuatu. A second key concern was to design a program that would cater for participants who were working full time, who were not all living in the same physical location, and who had limited access to internet technology and resources. The course also needed to take into account that participants were multilingual, and that English was not their first language. LESSONS LEARNED: Lessons learned included the importance of coming to understand the sociocultural nexus within which this course was developed and implemented, as well as appreciating the constraints that affect nursing education within the Pacific

    On the flow of kaons produced in relativistic heavy ion collisions

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    We investigate the different contributions to the in-plane flow of K+ mesons observed recently by the FOPI collaboration in the reaction Ni(1.93 AGeV)+Ni. Due to the kinematics of the three body phase space decay the flow of kaons produced in baryon-baryon interactions is smaller than that of the baryons in the entrance channel. On the contrary, in pi N interactions the flow of the sources and of the kaons are identical. Therefore the total kaon flow depends on the relative number of Delta N -> K+ and pi N -> K+ reactions and hence on the lifetime of the Delta, in addition to the already known dependence on the potential interaction interaction of the kaons with the nuclear environment.Comment: 11 pages, 10 figures, submitted to NP

    Parent-child interaction in Nigerian families: conversation analysis, context and culture

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    This paper uses a conversation analysis (CA) approach to explore parent child interaction (PCI) within Nigerian families. We illustrate how speech and language therapists (SLTs), by using CA, can tailor recommendations according to the interactional style of each individual family that are consonant with the family’s cultural beliefs. Three parent-child dyads were videoed playing and talking together in their home environments. The analysis uncovered a preference for instructional talk similar to that used in the classroom. Closer examination revealed that this was not inappropriate when considering the context of the activities and their perceived discourse role. Furthermore, this was not necessarily at the expense of responsivity or semantic contingency. The preference for instructional talk appeared to reflect deeply held cultural beliefs about the role of adults and children within the family and it is argued that the cultural paradigm is vitally important to consider when evaluating PCI. Given a potential risk that such young children may be vulnerable in terms of language difficulties, we offer an example of how PCI can be enhanced to encourage language development without disrupting the naturally occurring talk or the underlying purpose of the interaction
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