612 research outputs found
Shock temperature measurements in metals: New results for an Fe alloy
The temperature of a Fe-Cr-Ni alloy (304 stainless steel) has been measured during shock compression using a high-speed radiometric technique. Experiments were performed on high-quality thick films deposited on sapphire and LiF windows. The samples had no observable porosity or defects and closely meet the ideal criteria for shock temperature measurements. Data obtained with both Al_2O_3 and LiF windows are internally consistent, indicating that they remain transparent to high pressures and are thus suitable windows for shock temperature measurements. Our data yield stainless steel melting temperatures ranging from 4570±310K at 138 GPa to 5710±340 K at 215 GPa, and additionally provide bounds on the initial Hugoniot temperatures of the sample between 5600±340 K at 234 GPa (near the solidus) and 6580±440 K at 283 (in the liquid field). Taken together, these data define a smooth curve for melting of the alloy up to 271 GPa and 5860 K, which should represent a point on the Iiquidus. Melting along the Hugoniot begins at approximately 234 GPa and 5600 K, as compared with 242 GPa and 6400 K for pure Fe. At the pressure of the inner core-outer core boundary, the melting point of 304 stainless steel is lower than that of pure Fe by â 1450 K, as compared with only 110 K at 1 atm. These results demonstrate that upon alloying with Ni and Cr the melting point depression of Fe and thus material likely to comprise the inner core increases with increasing pressure
A clinical comparison of visual acuity between the Cardiff acuity test and the Teller acuity and Snellen acuity tests in an adult population
The newly introduced Cardiff Acuity Test developed at the University of Wales College, Cardiff UK was compared to the standard Snellen Acuity charts and the Teller Acuity cards. Acuity readings were obtained from 100 eyes (50 subjects) at distances of 1 meter and 3 meters. A significant difference was found between the 3 acuity tests with a greater deviation at distance (3 meters) than at near (1 meter). The Teller cards measured the highest (best) acuity level followed by the Cardiff and the Sneilen measuring the lowest (worst) acuity
Structures and visco-elastic properties of potassium tellurite: glass versus melt
The structure and visco-elastic properties of K2Te4O9 have been examined as a function of temperature, using neutron scattering and Brillouin light scattering, respectively. The neutron scattering data indicate that the coordination of tellurium by oxygen changes notably once the material is heated above the glass transition temperature. This and the associated decrease in elastic modulus are consistent with converting network building blocks from trigonal bipyramids to trigonal pyramids. The latter form chain-like structures that constitute a liquid characterized by a single relaxation mechanism. Structural relaxation in the liquid results in further decrease of its elastic storage capacity and in a maximum of dissipative losses due to viscous processes. The break-up of the glassy network, which is attributed to a frictionless transformation of building blocks, is distinct from the viscous relaxation of the liquid; their visco-elastic signatures can be observed in separate temperature intervals.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48897/2/cm6_3_009.pd
Investigation of the Core-Shell Interface in Gold@Silica Nanoparticles: A Silica Imprinting Approach
Expert Premier League soccer managersâ use of transformational leadership behaviours and attitude towards sport integrity: An intrinsic case study
The present study is the first to examine transformational leadership behaviours and integrity attitudes of expert, Premier League and International level football managers. To provide a rich, detailed exploration of the expert managersâ experiences, a qualitative approach was adopted utilising holistic content analysis. Constructed narratives revealed that the key behaviours demonstrated were inspirational messages or team talks (i.e. inspirational motivation), empathy (i.e. individualised consideration), introducing new training methods (i.e. intellectual stimulation), using exemplar players (i.e. appropriate role modelling), and goal setting (i.e. high performance expectations). However, the use and effect of such behaviours varied greatly between managers. Each of the managers also claimed to have been willing to âbend the rulesâ as a player and frequently used euphemistic labels to describe such behaviour. However, upon entering management, all three managers claimed to have adjusted such attitudes without providing an explanation for this
Results of the combined U.S. multicenter postapproval study of the NitâOcclud PDA device for percutaneous closure of patent ductus arteriosus
ObjectivesTo report the results of the NitâOcclud PDA prospective postapproval study (PAS) along with a comparison to the results of the pivotal and continued access trials.BackgroundThe NitâOcclud PDA (PFM Medical, Cologne, Germany), a nitinol coil patent ductus arteriosus (PDA) occluder, was approved by the Food and Drug Administration in 2013.MethodsThe PAS enrolled a total of 184 subjects greater than 6âmonths of age, weighing at least 5âkg, with PDAs less than 4 mm by angiography at 11 centers. Patients were followed prospectively at 2 months, 12âmonths, and 24âmonths postprocedure. These outcomes were compared to the 357 subjects enrolled in the pivotal and continued access protocols. Efficacy and safety data were reported.ResultsAmong 184 subjects enrolled for the PAS between 2014 and 2017, 180 (97.8%) had successful device implantation. After 12âmonths, 98.7% (150/152) had trivial or no residual shunt by echocardiography and two subjects had only small residual shunts. There were three device embolizations that were all retrieved by snare without clinical consequence. Together with the pivotal and continued access study, 97.4% (449/461) had complete echocardiographic closure at 12âmonths in 541 enrolled subjects. The composite success was 94.4%. There were no mortalities and no serious deviceârelated adverse events.ConclusionsThe NitâOcclud PDA is a safe and effective device for closure of a small to moderate sized PDA. There were no serious deviceârelated adverse events in a large cohort of three clinical trials.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/148398/1/ccd27995_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/148398/2/ccd27995.pd
Existential Communication and Leadership
The aim of this article is to introduce and explain a number of important existentialist philosophers and concepts that we believe can contribute to a critical approach to leadership theory. Emphasis is placed on understanding the nature of communication from an existentialist perspective and so Jaspers' conceptualization of existential communication is introduced along with important related concepts that may be regarded as important facets of leader communication including Being-in-the-world, the Other, intersubjectivity, dialogue and indirect communication. Particular attention is paid to Buber's ideas on communication as relationship and dialogue. Throughout, reference is made to contemporary, and what is often regarded as orthodox, thinking regarding the centrality of communication to leadership practice as a means by which to highlight the salience of an existentialist analysis
Australia\u27s health 1994 : the fourth biennial report of the Australian Institute of Health and Welfare
Australia\u27s Health is the most comprehensive and authoritative source of national information on health in Australia. Australia\u27s Health is published mid-year in even-numbered years and provides national statistics and related information that form a record of health status, service provision and expenditure in Australia
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