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In the present paper, we review 4 topics that were identified through extensive consultation with stakeholders as issues of high impact and influence for the grains industry: improving soil testing and interpretation; role of fluid fertilisers in the Western Australian (WA) grains industry; using spatial and temporal information to improve crop nutrient management, particularly for nitrogen; and developing recommendations for managing emerging nutrient deficiencies. The key findings are summarised below. To further improve soil testing and interpretation, the review suggests that future research should focus on addressing soil sampling and interpretation questions, as they are important factors affecting the accuracy of fertiliser recommendations with changing cropping practices. There have been several studies to compare fluid with granular forms of P in WA, but the responses have not, so far, been consistent. More work may be needed to understand different crop response to fluid P fertiliser additions, particularly on low pH soils in WA. An understanding of the long-term performance of fluid P will also require an assessment of the residual value of fluid P compared with granular P under field conditions. Precision agriculture (PA) technology has potential to improve crop nutrient management and farm profitability in WA. The review indicates that understanding both spatial and temporal yield variation is critical for the successful adoption of PA technology by growers. The review also suggests that in WA, there is a need to explore the use of different layers of spatial information for determining management zones. In response to wide adoption of no-till and stubble retention cropping systems, increased use of fluid fertilisers together with advanced application technologies, and increased interest in cropping in the high rainfall zone, there is need to better understand growers' practices and attitudes to crop nitrogen (N) management, and thus to better position research and extension activities. The review also suggests the need to evaluate new fertiliser products and site-specific N management concepts and develop N management practices for waterlogging-prone soils for improved N use efficiency in cereal production systems in WA. The negative balance of magnesium (Mg) observed in WA cropping systems, together with the information reviewed on factors affecting soil Mg content and crop response to Mg application across Australia, suggests that there is a need to evaluate the risk and impact of Mg deficiency on acidic sandy soils of WA. Additional keywords: copper, fluid fertilisers, molybdenum, nutrient deficiencies, soil testing and sampling, sulfur, tactical nitrogen management, zero-till cropping, zinc., Introduction Fertiliser costs represent a significant part of the variable costs of growing grain crops in the Mediterranean-type environment of Western Australia (WA). For example, the State average expenditure on [...]

Acquired immunity to Streptococcus pneumoniae (pneumococcus) has long been assumed to depend on the presence of anticapsular antibodies. We found, however, that colonization with live pneumococci of serotypes 6B, 7F, or 14 protected mice against recolonization by any of the serotypes and that protection from acquisition of a heterologous or homologous strain did not depend on anticapsular antibody. Further, intranasal immunization by live pneumococcal colonization or by a killed, nonencapsulated whole-cell vaccine protected antibody-deficient mice against colonization, suggesting independence of antibodies to any pneumococcal antigens. Protection by intranasal immunization with whole-cell vaccine was completely abrogated in T cell-deficient mice, and in mice that were congenitally deficient in CD[4.sup.+] T cells or depleted of these cells at the time of challenge. In contrast, mice congenitally deficient in, or depleted of, CD[8.sup.+] T cells were fully protected. Protection in this model was observed beyond 2 months after immunization, arguing against innate or nonspecific immune mechanisms. Thus, we find that immunity to pneumococcal colonization can be induced in the absence of antibody, independent of the capsular type, and this protection requires the presence of CD[4.sup.+] T cells at the time of challenge. Streptococcus pneumoniae | cell-mediated immunity | vaccine

The major late promoter element (MLPE) was characterized as a second cathepsin D gene E2-reponsive region. Results identify an imperfect palindromic ERE (CGCCCACGTACC) DNA sequence that binds the ER to make a retarded band in an electrophoretic mobility gel shift assay. Different biological and physiological processes was regulated by steroid hormone receptors by modulating tissue-specific expression of target genes.

A ray-tracing calculation that uses reflection and transmission coefficients for layers with refract matched boundaries leads to the corresponding coefficients for refractive-index mismatch. The model compared with Monte Carlo calculations for a range of layer parameters. The absorption by a mismatch layer is higher than the corresponding layer with matched boundaries and relatively insensitive to t extent of scattering anisotropy. The model should be useful for practical calculations on biological where refractive-index mismatch is usually present., Coefficients for refractive-index mismatch are obtained with a ray-tracing calculation using corresponding reflection and transmission coefficients for layers with refractive-index matched boundaries. Mismatched layer absorption is higher than the corresponding matched boundary layer and is relatively insensitive to the scattering anisotropy range. The model is expected to be useful for biological tissue calculations where refractive-index mismatch is usually present. Results are compared with Monte Carlo calculations for a range of layer parameters.