Pasture legume adaptation to six environments of the seasonally dry tropics of north Queensland

Production, regeneration and persistence of summer-growing pasture legumes were studied in plots (26 accessions) in 3 sub-coastal environments (>600 m elevation) and in rows (92 accessions) in 3 inland environments (30 m) during the experiment. In the row experiments, legume establishment and production were restricted by drought on the red earth and grey clay soils, and by waterlogging on a hard-setting solodic soil. After 4 years of drought and grazing, none of the 72 legumes sown on the fertile red earth had survived, although there was subsequent regeneration from seed. Desmanthus species and Clitoria ternatea were most productive and persistent, over 15 years, on the cracking clay soil, and Stylosanthes scabra cv. Seca and S. hamata cv. Verano were the only survivors on the solodic soil. Environmental limitations of the current pasture legume cultivars have been identified and legume genera are suggested for further evaluation and development under commercial grazing management and for special purpose pastures in these environments

Crop nutrition and the response to clay amendment of sands

Clay amendment of sands using clay-rich subsoils has occurred on over 160,000 ha in southern Australia, primarily to ameliorate water repellence. The implications of clay amendment for crop nutrition have not been examined, nor has there been much consideration given to the variation in subsoil properties and their effects on crop nutrition

Constraints on Initial AHS Deployment and the Concept Definition of a Shuttle Service for AHS Debut

Highway automation and its evolution involve a multitude of systems issues. Particularly important and difficult in defining a deployment sequence is the very first step, i.e. the first user service involving fully automated freeway driving. However, this importance and the difficulty imply that many factors may severely constrain the initial deployment. After discussing the paramount importance of initial AHS deployment, this paper points out major high-level issues and constraints. Any realistic deployment strategy must take into consideration gradual technology maturation, introduction of new driver role and diminishing conventional driver role for automated driving, high cost of early-generation automation-equipped vehicles, gradual infrastructure modification, gradual commitment of automakers to manufacture and service automation-equipped vehicles, gradual commitment of insurance industry to carry liability, and gradual acceptance by the interest groups and the general public. This paper then proposes a freeway shuttle van service for AHS debut. This user service could be a good candidate for the 1997 AHS demonstration required by ISTEA and has a good chance of leading to a successful long-term AHS deployment supported by the general public

Biochar and compost increase crop yields but the effect is short term on sandplain soils of Western Australia

Sandplain soils on the south coast of Western Australia have low inherent fertility, which is mainly due to poor nutrient retention caused by insufficient clay and organic colloidal material. Previous research has shown the benefits in nutrient levels and retention from adding clay to sandplain soils; however, there is almost no information on the addition of organic amendments. A field experiment was established at the Esperance Downs Research Station, Western Australian, in May 2010, to assess the effects of wheat straw (WS) and chicken manure (CM) biochars and compost with and without phosphorus (P) addition on soil properties and crop production over five growing seasons. The five seasons alternated between winter and summer crops. The CM and WS biochar and compost treatments significantly increased crop yields and P uptake in 3, 2 and 1 of the five seasons, respectively. The yield increases (. P < 0.05) were no more than 8%. By the end of the third season, no differences in crop yields were found that could be attributed to the organic amendments. The addition of P increased crop yields in each winter cropping season. Phosphorus addition explained more than 30% of the variation in crop yields. Despite marginal P levels and summer drought conditions, arbuscular mycorrhizal root colonisation was not affected by the organic amendments. There were no significant interactions between the organic amendments and P addition in terms of crop yields, P uptake or P uptake efficiency. We conclude that much of the effect of the organic amendments was due to direct nutrient addition which dissipated over time

Improved lower bounds for the ground-state energy of many-body systems

New lower bounds for the binding energy of a quantum-mechanical system of interacting particles are presented. The new bounds are expressed in terms of two-particle quantities and improve the conventional bounds of the Hall-Post type. They are constructed by considering not only the energy in the two-particle system, but also the structure of the pair wave function. We apply the formal results to various numerical examples, and show that in some cases dramatic improvement over the existing bounds is reached.Comment: 29 pages, 5 figures, to be published in Phys. Rev.

Jekyll and Hyde: men's constructions of feminism and feminists

Research and commentary on men's responses to feminism has demonstrated the range of ways in which men have mobilised both against and for feminist principles. This paper argues that further analyses of men's responses require a sophisticated theory of discourse acknowledging the fragmented and contradictory nature of representation. A corpus of men's talk on feminism and feminists was studied to identify the pervasive patterns in men's accounting and regularities in rhetorical organisation. Material from two samples of men was included: a sample of white middle-class 17-18 year old school students and a sample of 60 interviews with a more diverse sample of older men aged 20 to 64. Two interpretative repertoires of feminism and feminists were identified. These set up a 'Jekyll and Hyde' binary and positioned feminism along with feminists very differently as reasonable versus extreme and monstrous. Both repertoires tended to be deployed together and the paper explores the ideological and interactional consequences of typical deployments along with the identity work accomplished by the men as they positioned themselves in relation to these

Coupled-mode theory for Bose-Einstein condensates

We apply the concepts of nonlinear guided-wave optics to a Bose-Einstein condensate (BEC) trapped in an external potential. As an example, we consider a parabolic double-well potential and derive coupled-mode equations for the complex amplitudes of the BEC macroscopic collective modes. Our equations describe different regimes of the condensate dynamics, including the nonlinear Josephson effect for any separation between the wells. We demonstrate macroscopic self-trapping for both repulsive and attractive interactions, and confirm our results by numerical simulations.Comment: 4 pages, 5 figures; typos removed, figures amended; submitted to PR