361 resultados para maize primary root
Resumo:
The focus of this study is the celebration of Eucharist in Catholic primary schools within the Archdiocese of Brisbane. The context of the contemporary Australian Catholic primary school embodies certain 'problematical realities' in relation to the time-honoured way in which school Eucharistic rituals have been celebrated. These contemporary realities raise a number of issues that impact on school celebrations of Eucharist. The purpose of this study is to explore administrators' differing conceptions of school Eucharistic rituals in an attempt to investigate some of these issues and assist members of individual school communities as they strive to make celebrations of Eucharist appropriate and meaningful for the group gathered. The phenomenographic research approach was adopted, as it is well suited to the purpose of this study and the nature of the research question. Phenomenography is essentially a study of variation. It attempts to map the 'whole' phenomenon under investigation by describing on equal terms all conceptions of the phenomenon and establishing an ordered relationship among them. The purpose of this study and the nature of the research question necessitate an approach that allows the identification and description of the different ways in which administrators' experience school Eucharistic rituals. Accordingly, phenomenography was selected. Members of the Administration Team, namely the principal, the APRE (Assistant to the Principal Religious Education) and, in larger primary schools, the AP A (Assistant to the Principal Administration) share responsibility for leading change in Catholic primary schools in the Archdiocese of Brisbane. In practice, however, principals delegate the role of leading the development of the school's religion program and providing leadership in the religious life of the school community to the APRE (Brisbane Catholic Education, 1997). Informants in this study are nineteen APREs from a variety of Catholic primary schools in the Archdiocese of Brisbane. These APREs come from schools across the archdiocese, rather than from within one particular region. Several significant findings resulted from this study. Firstly, the data show that there are significant differences in how APREs' experience school Eucharistic rituals, although the number of these qualitatively different conceptions is quite limited. The study identifies and describes six distinct yet related conceptions of school Eucharistic rituals. The logical relationship among these conceptions (the outcome space) is presented in the form of a diagram with accompanying explication. The variation among the conceptions is best understood and described in terms of three dimensions of the role of Eucharist in the Catholic primary school and is represented on the model of the outcome space. Individual transcripts suggest that individual APREs tend to emphasise some conceptions more than others. It is the contention of the present study that change in the practice of school Eucharistic rituals is unlikely to occur until all of a school community's conceptions are brought out into the open and articulated. As leaders of change, APREs need to be alerted to their own biases and become aware of alternative ways of conceiving school Eucharistic ritual. It is proposed that the different categories of description and dimensions, represented by the model of the outcome space, can be used to help in the process of articulating a school community's conceptions of Eucharist, with the APRE as facilitator of this process. As a result, the school community develops a better understanding of why their particular school does what it does in relation to school Eucharistic rituals.
Resumo:
One approach to reducing the yield losses caused by banana viral diseases is the use of genetic engineering and pathogen-derived resistance strategies to generate resistant cultivars. The development of transgenic virus resistance requires an efficient banana transformation method, particularly for commercially important 'Cavendish' type cultivars such as 'Grand Nain'. Prior to this study, only two examples of the stable transformation of banana had been reported, both of which demonstrated the principle of transformation but did not characterise transgenic plants in terms of the efficiency at which individual transgenic lines were generated, relative activities of promoters in stably transformed plants, and the stability of transgene expression. The aim of this study was to develop more efficient transformation methods for banana, assess the activity of some commonly used and also novel promoters in stably transformed plants, and transform banana with genes that could potentially confer resistance to banana bunchy top nanovirus (BBTV) and banana bract mosaic potyvirus (BBrMV). A regeneration system using immature male flowers as the explant was established. The frequency of somatic embryogenesis in male flower explants was influenced by the season in which the inflorescences were harvested. Further, the media requirements of various banana cultivars in respect to the 2,4-D concentration in the initiation media also differed. Following the optimisation of these and other parameters, embryogenic cell suspensions of several banana (Musa spp.) cultivars including 'Grand Nain' (AAA), 'Williams' (AAA), 'SH-3362' (AA), 'Goldfinger' (AAAB) and 'Bluggoe' (ABB) were successfully generated. Highly efficient transformation methods were developed for both 'Bluggoe' and 'Grand Nain'; this is the first report of microprojectile bombardment transformation of the commercially important 'Grand Nain' cultivar. Following bombardment of embryogenic suspension cells, regeneration was monitored from single transfom1ed cells to whole plants using a reporter gene encoding the green fluorescent protein (gfp). Selection with kanamycin enabled the regeneration of a greater number of plants than with geneticin, while still preventing the regeneration of non-transformed plants. Southern hybridisation confirmed the neomycin phosphotransferase gene (npt II) was stably integrated into the banana genome and that multiple transgenic lines were derived from single bombardments. The activity, stability and tissue specificity of the cauliflower mosaic virus 358 (CaMV 35S) and maize polyubiquitin-1 (Ubi-1) promoters were examined. In stably transformed banana, the Ubi-1 promoter provided approximately six-fold higher p-glucuronidase (GUS) activity than the CaMV 35S promoter, and both promoters remained active in glasshouse grown plants for the six months they were observed. The intergenic regions ofBBTV DNA-I to -6 were isolated and fused to either the uidA (GUS) or gfjJ reporter genes to assess their promoter activities. BBTV promoter activity was detected in banana embryogenic cells using the gfp reporter gene. Promoters derived from BBTV DNA-4 and -5 generated the highest levels of transient activity, which were greater than that generated by the maize Ubi-1 promoter. In transgenic banana plants, the activity of the BBTV DNA-6 promoter (BT6.1) was restricted to the phloem of leaves and roots, stomata and root meristems. The activity of the BT6.1 promoter was enhanced by the inclusion of intron-containing fragments derived from the maize Ubi-1, rice Act-1, and sugarcane rbcS 5' untranslated regions in GUS reporter gene constructs. In transient assays in banana, the rice Act-1 and maize Ubi-1 introns provided the most significant enhancement, increasing expression levels 300-fold and 100-fold, respectively. The sugarcane rbcS intron increased expression about 10-fold. In stably transformed banana plants, the maize Ubi-1 intron enhanced BT6.1 promoter activity to levels similar to that of the CaMV 35S promoter, but did not appear to alter the tissue specificity of the promoter. Both 'Grand Nain' and 'Bluggoe' were transformed with constructs that could potentially confer resistance to BBTV and BBrMV, including constructs containing BBTV DNA-1 major and internal genes, BBTV DNA-5 gene, and the BBrMV coat protein-coding region all under the control of the Ubi-1 promoter, while the BT6 promoter was used to drive the npt II selectable marker gene. At least 30 transgenic lines containing each construct were identified and replicates of each line are currently being generated by micropropagation in preparation for virus challenge.