Travelling modes in wave-heated plasma sources

This paper describes a theoretical and experimental study of surface- and helicon-wave-heated plasma sources in which standing waves are set up in the cavity between the closed end plate to a plasma vessel and a wave launcher while travelling waves propagate from the opposite side of the launcher into a region which is long compared with the attenuation distance of the waves. We model the situation as a lossy transmission line of finite length coupled at the launcher to a lossy transmission line of infinite extent. RF power applied to the launcher divides in the ratio of the input impedances of the two transmission lines. For a conducting end plate, the power delivered to the travelling waves is a maximum when the cavity length is an odd number of 1/4 wavelengths long for which its input impedance is a maximum. Similarly, for an insulated end plate, the power delivered to the travelling waves is a maximum for a cavity with a length equal to an integer number of half wavelengths for which its input impedance is again a maximum

The Baroque Concertato in England, 1625–c.1660 Volume I & II

English concertato music of the seventeenth century has remained a relatively neglected area of musicological scholarship and has yet to receive the attention it deserves. More specifically, the period between the death of William Byrd (1540–1623) and the rise of Henry Purcell (1659–1695) remains something of a historiographical lacuna and is often disparaged for the decline in English musical standards. It is demonstrated in this dissertation, however, that in certain Royalist and court-related circles English composers were conversant in the stile nuovo and remained absolutely up-to-date with the latest Italian methods of composition. An attempt is made to construct a paradigm of influence that can be used profitably when considering the appropriation and assimilation of the techniques of the stile nuovo by English composers. The first composer to be examined in this dissertation is Richard Dering (1580–1620), who should be considered the progenitor of small-scale concertato music in England. The chief pioneer of Italianate sacred music in mid-seventeenth-century England, however, was George Jeffreys (1610–1685), who has been marginalised by traditional constructions of English music history. It is hoped that this dissertation is, in part, remedial, drawing attention to the significant achievements made by Jeffreys, while simultaneously promoting English concertato music. In the latter part of this dissertation the music of William Child (1606/7–1697), Henry Lawes (1596–1662) and William Lawes (1602–1645), Walter Porter (c.1587/c.1595–1659), and John Wilson (1597–1674) is considered in a series of case studies, all of whom demonstrate Royalist allegiances and a commitment to the stile nuovo. The complexities of the political and religious concerns of the period are also highlighted and detailed alongside the music of these composers

Using Mathematical Packages in Advanced Science and Engineering Units

Much of the subject material in high level science and engineering units is strongly based on advanced mathematics and requires a high level of mathematical skill on behalf of the students. This is particularly true of subjects like Signal Analysis, Electromagnetics and Control Systems. These skills are usually acquired during the mathematical strand of the course. Previously, assignment problems presented in these subjects had to be solvable by hand, that is with algebraic manipulation and a calculator. This has two distinct consequences: • For realistic problems, more time is spent on advanced but routine mathematical manipulations than on the conceptual principles of the subject material; and • Problems that are solvable by hand (the problem must be carefully posed such that the solution will drop out in analytic form to second order, i.e. quadratic) are necessarily highly theoretical, simplified and unrealistic. For these reasons it was thought that the routine use of an advanced mathematical package would transform these subjects from a mathematical slog to a higher conceptual level with the student putting the intellectual effort into mathematical formulation and analysis of problems with the package performing the mathematical grind. The use of such a package would address both of the above problems in that more time would be spent on addressing the conceptual material and would allow more realistic and complicated problems to be posed and addressed

Defects and disorder in metal organic frameworks

International audienceThe wide-ranging properties of metal organic frameworks (MOFs) rely in many cases on the presence of defects within their structures and the disorder that is inevitably associated with such defects. In the present work we review several aspects of defects in MOFs, ranging from simple substitutional defects at metal cation or ligand positions, to correlated defects on a larger length scale and the extreme case of disorder associated with amorphous MOFs. We consider both porous and dense MOFs, and focus particularly on the way in which defects and disorder can be used to tune physical properties such as gas adsorption, catalysis, photoluminescence, and electronic and mechanical properties

Defects and disorder in metal organic frameworks.

The wide-ranging properties of metal organic frameworks (MOFs) rely in many cases on the presence of defects within their structures and the disorder that is inevitably associated with such defects. In the present work we review several aspects of defects in MOFs, ranging from simple substitutional defects at metal cation or ligand positions, to correlated defects on a larger length scale and the extreme case of disorder associated with amorphous MOFs. We consider both porous and dense MOFs, and focus particularly on the way in which defects and disorder can be used to tune physical properties such as gas adsorption, catalysis, photoluminescence, and electronic and mechanical properties.The authors would like to thank Ras Al Khaimah Center for Advanced Materials (AKC, TDB), Trinity Hall (TDB), and the ERC (ALG, Grant 279705).This is the author accepted manuscript. The final version is available from RSC via http://dx.doi.org/10.1039/C5DT04392

What doesn’t kill you makes you fitter: A systematic review of high-intensity interval exercise for patients with cardiovascular and metabolic diseases

High-intensity interval exercise (HIIE) has gained popularity in recent years for patients with cardiovascular and metabolic diseases. Despite potential benefits, concerns remain about the safety of the acute response (during and/or within 24 hours postexercise) to a single session of HIIE for these cohorts. Therefore, the aim of this study was to perform a systematic review to evaluate the safety of acute HIIE for people with cardiometabolic diseases. Electronic databases were searched for studies published prior to January 2015, which reported the acute responses of patients with cardiometabolic diseases to HIIE (≥80% peak power output or ≥85% peak aerobic power, VO2peak). Eleven studies met the inclusion criteria (n = 156; clinically stable, aged 27–66 years), with 13 adverse responses reported (~8% of individuals). The rate of adverse responses is somewhat higher compared to the previously reported risk during moderate-intensity exercise. Caution must be taken when prescribing HIIE to patients with cardiometabolic disease. Patients who wish to perform HIIE should be clinically stable, have had recent exposure to at least regular moderate-intensity exercise, and have appropriate supervision and monitoring during and after the exercise session

Physics teacher retraining through flexible delivery

The Graduate Certificate of Physics (GCP) described in this paper is a response to two recent educational phenomena. The first is the escalating shortage of teachers in the physical sciences, and the second is the rapid development of increasingly sophisticated platforms for online delivery. A particular requirement of this retraining course was the capacity to cater for science teachers in rural areas of NSW, where secondary schools had a need for trained physics teachers. Distance education has, traditionally, been used to fulfill the needs of isolated students but has been regarded as a less desirable and more expensive alternative to more traditional models. The advent of computer-based learning has led to the possibility that flexible delivery modes may become as effective as traditional, on campus courses. In a recent review of the effectiveness of online education Jung and Rha (2000) suggest that reduced costs and increased revenue have been major factors in the drive towards online education, but many studies purport to show that online delivery modes produce educational outcomes that are generally as effective as more traditional face-to-face modes. Some observations (Inglis 1999) suggest that online education may produce improved educational outcomes through wider access to a variety of multimedia resources and information combined, surprisingly, with increased opportunities for interaction with other students and instructors. It has often been assumed that missing out on traditional experiences such as lectures compromises the quality of the learning by distance experience. Biggs (1999; p.113) describes how, at the institution where he taught, parity between internal and external students was maintained by denying the internal students access to the external lecture notes, to make up for the advantage the internal students had in being able to attend the on-campus lectures. In fact, numerous studies suggest that distance education often seems to be as effective and sometimes more effective than traditional modes (Jung and Rha 2000). Some recent studies of courses that have been delivered online suggest a high level of acceptance by students (Chang and Fisher 1999; McConnell and Shoenfeld-Tachner 2002). The latter study involved a science course (in histology) in the USA. Students in this course judged it to be ‘readily accessible and at least equal in academic rigour to comparable on-campus courses.’ One of the main issues in the development of the course described in that paper was the incorporation of appropriate laboratory work. Our belief that a substantial laboratory-based experience was needed was the main reason for incorporating a residential component into the GCP. This paper explores the tension between flexible/distance teaching modes of delivery and the more traditional teaching and learning environments provided during the residential component of this course

Learning to teach physics – Online

The University of Canberra Schools of Teacher Education and of Electronics and Telecommunications Engineering have established a new Graduate Certificate in Physics Education. The course has been designed to meet the needs of the NSW Department of Education and Training (DET) and provides an integrated combination of physics content knowledge, laboratory skills and pedagogic theory, specific to the teaching of physics, which will enable science educators to teach physics at secondary level to year 12 and take a leadership role at the school level in the planning and delivery of Preliminary and HSC Physics courses. The course is to target established science teachers with science degrees and teaching qualifications. These teachers will be sourced from anywhere in NSW and consequently the course will be delivered online. All teachers taking the course are fully funded by the NSW DET. Enrolments for 2002 are 32 with the prospect of a similar number for 2003. Designing such a course is a significant responsibility, as it could influence how physics will be taught in over 60 schools in NSW in the immediate future. In this poster we will discuss the intended objectives and content of the course, our philosophy behind the course content as well as the technicalities of how the course will be presented online