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As spans and slenderness of post-tensioned concrete office floors increase, their vibration behaviour is becoming increasingly important. Although now recognised worldwide to be an important design issue, detailed guidance on the checking of the vibration serviceability of post-tensioned floors is not readily available in national building codes of practice. The only detailed guidelines developed worldwide specifically for checking vibration serviceability of post-tensioned office floors have been published by the UK Concrete Society in 1994. These guidelines are generic, could be and are being used in countries where specific national guidance is lacking. However, the Concrete Society guidelines have been found to be problematic in each of the three key aspects of floor vibration serviceability assessment. First, in the modelling of walking excitation, an unrepresentative walking forcing function is assumed. Second, as the guidelines were not experimentally verified, some unwarranted assumptions and simplifications are made in the modelling of the floor structure, in particular its boundary conditions. Finally, the method of calculation of the floor responses is somewhat simplistic. Here, the possibility that modes of vibration higher than the fundamental may be excited in resonance by walking is neglected.

144 patients with severe rheumatoid arthritis from six centres were randomised to receive oral cyclosporin or placebo for 6 months. The initial daily dose of cyclosporin was 2·5 mg/kg, which was increased cautiously with monitoring of serum cyclosporin levels and creatinine; the mean stabilisation dose was 3·8 mg/kg. There were significant improvements in the cyclosporin-treated patients compared with the controls in the major outcomes of reduction of active joints (23% improvement), pain (24%), and functional status (16%); global improvement was 27%. In the cyclosporin group serum creatinine increased by a mean of 15·6 μmol/l and mean arterial blood pressure by 6·27 mm Hg; these increases were controlled in all but 2 patients by dose adjustment without withdrawal from the study.

Project Aria began in 1998 as a space projects course in the School of Engineering & Applied Science at Washington University, St. Louis. The first mission, Aria-1, was a passive GAS canister payload launched with STS-101 in September 2000; it contained 45 science experiments submitted by local K-12 schools. The success of Aria-1 has led to additional missions under Project Aria, including follow-on Shuttle flights, a student CubeSat project, a Mars rover prototype, research in spacecraft operations, and a high-altitude balloon prototype of a Venus probe. Project Aria is following the lead of other university space systems programs by incrementally developing student expertise and program capabilities. However, programs such as Aria must also meet the challenge of effectively educating students while producing meaningful research results. In addition, Project Aria was chartered to provide educational initiatives for the St. Louis public, and therefore these broader educational needs must also be addressed. The conflict among these three objectives forms a case study for this paper. This paper briefly describes the history of Project Aria and discusses the missions currently in development. Particular attention is paid to the manner in which Aria missions are managed, and also to successes and failures in balancing the needs of research, education, and public outreach. Lessons learned from Aria missions can be applied to other universities seeking to develop project-based programs.

The newly acquired 3,590 km 2 Demeter 3D high resolution seismic survey covers most of the North West Shelf Venture (NWSV) area; a prolific hydrocarbon province with ultimate recoverable reserves of greater than 30 Tcf gas and 1.5 billion bbls of oil and natural gas liquids. The exploration and development of this area has evolved in parallel with the advent of new technologies, maturing into the present phase of revitalised development and exploration based on the Demeter 3D. The NWSV is entering a period of growing gas market demand and infrastructure expansion, combined with a more diverse and mature supply portfolio of offshore fields. A sequence of satellite fields will require optimised development over the next 5-10 years, with a large number of wells to be drilled. The NWSV area is acknowledged to be a complex seismic environment that, until recently, was imaged by a patchwork of eight vintage (1981-98) 3D seismic surveys, each acquired with different parameters. With most of the clearly defined structural highs drilled, exploration success in recent years has been modest. This is due primarily to severe seismic multiple contamination masking the more subtle and deeper exploration prospects. The poor quality and low resolution of vintage seismic data has also impeded reservoir characterisation and sub-surface modelling. These sub-surface uncertainties, together with the large planned expenditure associated with forthcoming development, justified the need for the Demeter leading edge 3D seismic acquisition and processing techniques to underpin field development planning and reserves evaluations. The objective of the Demeter 3D survey was to re-image the NWSV area with a single acquisition and processing sequence to reduce multiple contamination and improve imaging of intra-reservoir architecture. Single source (133 nominal fold), shallow solid streamer acquisition combined with five stages of demultiple and detailed velocity analysis are considered key components of Demeter. The final Demeter volumes were delivered early 2005 and already some benefits of the higher resolution data have been realised, exemplified in the following: * Successful drilling of development wells on the Wanaea, Lambert and Hermes oil fields and identification of further opportunities on Wanaea-Cossack and Lambert-Hermes; ○ Dramatic improvements in seismic data quality observed at the giant Perseus gas field helping define seven development well locations; ○ Considerably improved definition of fluvial channel architecture in the south of the Goodwyn gas field allowing for improved well placement and understanding of reservoir distribution; ○ Identification of new exploration prospects and reevaluation of the existing prospect portfolio. Although the Demeter data set has given significant bandwidth needed for this revitalised phase of exploration and development, there remain areas that still suffer from poor seismic imaging, providing challenges for the future application of new technologies.

An extensive survey of native conifers ( Dacrydium, Podocarpus, Libocedrus, Phyllocladus and Agathis spp.) showed that C 2 H 2 reduction was often associated with their mycorrhizal short roots (‘nodules’). C 2 H 2 reduction was associated with roots only if it also occurred in surrounding soil, but it could be found in soils and not in the root region. Over 50 per cent of the C 2 H 2 reduction activity could be removed by washing roots in distilled water while complete loss of activity occurred when they were surface sterilized with hypochlorite solution. C 2 H 2 reduction may also be associated with long roots of podocarps and roots of non-podocarp species. Fermenting and humifying horizons of forest soils showed much greater rates of C 2 H 2 reduction than either mineral soil or roots. Results suggest that previous claims for nitrogen fixation by podocarp roots can be attributed to nitrogen fixation by bacteria in the root region rather than by endophytic organisms.