Practice activity trends among oral and maxillofacial surgeons in Australia

© 2004 Brennan et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.BACKGROUND: The aim of this study was to describe practice activity trends among oral and maxillofacial surgeons in Australia over time. METHODS: All registered oral and maxillofacial surgeons in Australia were surveyed in 1990 and 2000 using mailed self-complete questionnaires. RESULTS: Data were available from 79 surgeons from 1990 (response rate = 73.8%) and 116 surgeons from 2000 (response rate = 65.1%). The rate of provision of services per visit changed over time with increased rates observed overall (from 1.43 ± 0.05 services per visit in 1990 to 1.66 ± 0.06 services per visit in 2000), reflecting increases in pathology and reconstructive surgery. No change over time was observed in the provision of services per year (4,521 ± 286 services per year in 1990 and 4,503 ± 367 services per year in 2000). Time devoted to work showed no significant change over time (1,682 ± 75 hours per year in 1990 and 1,681 ± 94 hours per year in 2000), while the number of visits per week declined (70 ± 4 visits per week in 1990 to 58 ± 4 visits per week in 2000). CONCLUSIONS: The apparent stability in the volume of services provided per year reflected a counterbalancing of increased services provided per visit and a decrease in the number of visits supplied.David S Brennan, A John Spencer, Kiran A Singh, Dana N Teusner and Alastair N Gos

Codifying a Commons: Copyright, Copyleft, and the Creative Commons Project

In response to problems of overprotection perceived in America\u27s copyright scheme, the founders of the Creative Commons project have sought to create modular licenses allowing authors and artists to declaim some of the default protections associated with their copyright in order to grant public permission for use of their work in contexts such as nonprofit media or derivative works. This article reviews criticisms of the Creative Commons project and analyzes the project from the standpoint of copyright\u27s overall policy goals, both domestically and internationally. Because copyright policy seeks to enhance the public supply of information and knowledge, the article concludes that Creative Commons comports with underlying rationale for copyright protections. However, because of the private nature of the initiative, significant problems arise with questions of enforcement of the Creative Commons licenses as well as with Congressional goals of uniformity. The article suggests that many of the problems posed could be alleviated by codifying a means for copyright owners to opt for a more limited form of copyright within federal copyright law

Codifying a Commons: Copyright, Copyleft, and the Creative Commons Project

In response to problems of overprotection perceived in America\u27s copyright scheme, the founders of the Creative Commons project have sought to create modular licenses allowing authors and artists to declaim some of the default protections associated with their copyright in order to grant public permission for use of their work in contexts such as nonprofit media or derivative works. This article reviews criticisms of the Creative Commons project and analyzes the project from the standpoint of copyright\u27s overall policy goals, both domestically and internationally. Because copyright policy seeks to enhance the public supply of information and knowledge, the article concludes that Creative Commons comports with underlying rationale for copyright protections. However, because of the private nature of the initiative, significant problems arise with questions of enforcement of the Creative Commons licenses as well as with Congressional goals of uniformity. The article suggests that many of the problems posed could be alleviated by codifying a means for copyright owners to opt for a more limited form of copyright within federal copyright law

Closed loop fiber optic rotation sensor

An improved optical gyroscope is provided, of the type that passes two light components in opposite directions through an optic fiber coil, and which adds a small variable frequency to one of the light components to cancel the phase shift due to rotation of the coil. The amount of coil rotation from an initial orientation, is accurately determined by combining the two light components, one of which has a slightly increased frequency, to develop beats that each represent a predetermined angle of rotation. The direction of rotation is obtained by combining the two light components on a photodetector, intermittently phase shifting a single light component by 90 deg and comparing the direction of change of photodetector output (+ or -) caused by the 90 deg shift, with the slope (+ or -) of the photodetector output at about the same time, when there is a 90 deg shift

Variations of the amplitudes of oscillation of the Be star Achernar

We report on finding variations in amplitude of the two main oscillation frequencies found in the Be star Achernar, over a period of 5 years. They were uncovered by analysing photometric data of the star from the SMEI instrument. The two frequencies observed, 0.775 c/d and 0.725 c/d, were analysed in detail and their amplitudes were found to increase and decrease significantly over the 5-year period, with the amplitude of the 0.725 c/d frequency changing by up to a factor of eight. The nature of this event has yet to be properly understood, but the possibility of it being due to the effects of a stellar outburst or a stellar cycle are discussed.Comment: 6 pages, 6 figures, 1 table, to be published in MNRA