Successful efficient whole cauliflower plant regeneration via somatic embryogenesis from root derived callus tissue was achieved. The research confirmed for the first time the capability of mass production of cauliflower somatic embryos through the indirect pathway. The best callus induction and proliferation was on semi solid Murashige and Skoog (MS) medium supplemented with 2, 4-D at 0.15 mg L-1 and Kinetin at 0.1 mg L-1 and 3% sucrose. The response of different explant types (cotyledon, hypocotyls and root) through callus induction and subsequent culture was determined. The best period for subsequent callus culture was 21 days. Continuous immersion in agitated liquid medium technique was subsequently used for primary somatic embryo production. The culture requirements were empirically optimized including: explants source and size of callus tissue, blending duration, plant growth regulator combinations and concentrations as well as carbohydrate type and concentration. The highest mean number of somatic embryos (30.9) per explant was achieved using root derived embryogenic callus tissue on MS medium provided with IAA 0.05 mgL-1 and Kinetin at 0.5 mgL-1 and 2% sucrose. Somatic embryos were developed and matured on this medium and germinated with the highest percentage (60%) on semi-solid MS medium devoid of growth regulators. The culture conditions that led to the formation of secondary somatic embryos were identified. The presence of activated charcoal in the culture medium had an effect on this process but some abnormality of secondary somatic embryos was observed. Artificial seeds were produced by encapsulating the somatic embryos with a sodium alginate gel (2%) and complexing with calcium chloride (100 mM) for 20 min. The ability of these artificial seed for germination was evaluated using various combinations of plant growth regulators that were either incorporated in the artificial matrix or in the germination semi-solid culture medium. It was confirmed that cauliflower root derived embryogenic callus tissue can be cryopreserved following a preculture-dehydration technique. Following cryopreservation, embryogenic cultures can proliferate in agitated liquid medium, and somatic embryos at the globular stage were formed. Also cold storage at 5 °C in the dark was used successfully to store cauliflower callus tissue for three months without diminution of the competence for somatic embryos formation. This ability for cold storage could have a positive effect in reducing costs and efforts that result from subsequent sub-culture. The encapsulation-dehydration technique was assessed for cryopreservation of somatic embryos but failed to lead to survival of any embryos. Somatic embryos that were produced in this study were able to be well acclimated using a reliable weaning procedure that achieved high rates of survival of plantlets and their subsequent growth to normal plants in the field was assessed. Morphological characteristics of somatic plants compared favourably with zygotic plants but although there was phenotypic similarity, some differences in plant height, curd size and time for curd maturity were observed.

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Studies of somatic cell genetics in larches (Larix spp.) were carried out using somatic hybridization, cytogenetics as well as fluorescence in situ hybridization. Haploid embryogenic protoplasts are ideal sources for somatic hybridization if they possess stable chromosome complements. In my protoplast fusion experiments, I used diploid embryogenic protoplasts because genetic variation was detected in the haploid lines available. Cytogenetics coupled with fluorescence in situ hybridization was used to reveal genetic instabilities in haploid embryogenic lines as well as to produce a standard karyotype of Larix decidua. A diploid embryogenic culture of tamarack (Larix laricina, line L2) was used as one of the fusion partners while the other partner used was one of the two hybrid larches (Larix x leptoeuropaea, line L5 and Larix x eurolepis, line L6 ). The selection system was based on complementation of metabolic inhibition (with sodium iodoacetate) of tamarack and the lack of ability to produce mature embryos of the hybrid larches. Ideally, only the heterofused cells would have been able to regenerate. The vital fluorescent dyes, DiOC₆ and R6 , were used to stain protoplasts of each parent to determine fusion events and frequencies. I compared fusion firequency as well as cell division between fusion mediated by PEG or electric pulses. PEG-mediated fusion resulted in 14-18 % of heterofused cells. All electrofusion treatments gave much lower fusion frequencies, at only 4-8 %. Although the percentages of cell division after 4d of PEG-fusion (17-24%) and electrofusion (19.3%) were about the same, PEG-fusion was found to be a more efficient means than electrofusion. Sodium iodoacetate at a concentration of 4-5 mM was found to efficiently inactivate the protoplasts of tamarack. All control-treated protoplasts as well as mixed cultures (unfused protoplasts) died. Tamarack protoplasts produced mature single embryos, whereas protoplasts of hybrid larches never completed embryogenesis. Some post-fusion products produced colonies and mature embryos. RAPD was used to verify the hybridity of those fusion-derived colonies and mature embryos. Of thirty-one fusion experiments between lines L2 and L5, only one produced individual colonies. Of the thirteen colonies which developed in that experiment, none yielded mature embryos. RAPD analysis of the colonies picked out from L2/L5 fusion showed DNA banding characteristics of L5. From twenty four experiments fusing L2 and L6 , there were five experiments which produced colonies. A total of two hundred and thirty nine individual colonies and nineteen single mature embryos were picked out from those L2/L6 fusions. RAPD banding profiles of eighty seven colonies and nineteen mature embryos showed DNA banding characteristics of L2 only. Tested haploid embryogenic lines (total of 6 lines; n=12) of Larix decidua initiated from megagametophyte tissue were maintained on half-strength Litvay’s medium without growth regulators. All lines had been verified as being haploid by chromosome squashes when they were initiated. Some lines have been stably haploid for only a short period of time while others have been stable for many years. Variations in chromosome numbers increased proportionately with the age of the culture. Haploids doubled their chromosome numbers. Aneuploidization occurred because of unequal separation of the chromosomes. Unusual events during mitosis such as formation of anaphase bridges, fragmentation of chromosomes, and development of long kinetochores were detected. There was a tendency of rising chromosome numbers in all lines tested over the years. Fluorescence in situ hybridization (FISH) was used to physically map highly repetitive sequences of genes coding for 18S-5.8S-26S rDNA on Larix decidua chromosomes. A karyotype of L. decidua (2n=24) was created from average relative lengths derived from the six best squashes with strong probe-target FISH signals. Hybridization of 18S-26S rDNA onto L. decidua chromosomes gave very precise locations of secondary constriction as well as unexpressed nucleolar organizer regions. In L. decidua, there were 6 major 18S-26S rDNA loci detected in 60.53% of cells (23 out of 39 cells). Five I8S-26S rDNA loci were also found but at a lower rate of 39.47%. All loci were expressed and located at the sites of secondary constriction on chromosomes 2, 4 and 7. Two extra locations of 18S-26S rDNA were mapped on aneuploid chromosomes (30 chromosomes) derived from cells of an aneuploid line (line 2110) of L. decidua. Chromosome measurement resulted in a preliminary karyotype of this line. The relative total lengths and locations of I8S-26S rDNA of standard (2n=24) chromosomes and aneuploid (2n=30) chromosomes was compared. / Graduate

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L’objet de ce travail de thèse est une réflexion sur la façon dont le sujet peut se construire à l’adolescence, avec sa maladie. Je pars du postulat que quelque soit la maladie somatique chronique, des mécanismes seraient communs à tous les adolescents confrontés à cette maladie « depuis toujours-là ». Mon travail de recherche s’appuie sur sept vignettes cliniques d’adolescents hospitalisés dans notre unité soins-études. Le processus de subjectivation pour ces adolescents implique de composer avec un « travail de la maladie ». Un possible travail de subjectivation des parents en tant que « parents d’un enfant malade » peut leur permettre de ne pas se retrouver en impasse dans leur quête identitaire. Il s’agit pour ces adolescents de se réapproprier l’histoire de leur maladie afin de pourvoir devenir sujet. Après l’effraction suscitée par la maladie arrive la puberté, un moment de changements corporels qui n’épargne pas les adolescents atteints d’une maladie chronique, malgré le fantasme de certains patients à ce propos. Le corps malade devient un corps pubère avec la maladie et avec les remaniements pubertaires. Il semble nécessaire qu’un sentiment d’enveloppe « suffisamment bon » ait pu se constituer pendant l’enfance, afin de permettre à l’adolescent de ne pas se sentir trop insécurisé. Je rencontre les adolescents dans un contexte particulier : ils sont hospitalisés pour des soins, mais aussi pour leurs études, et sont donc séparés de leur famille. L’adolescent s’engage dès lors dans une démarche de soins, premier pas vers une demande de réflexion pour mieux appréhender sa maladie et comprendre comment se construire avec elle. Notre travail d’accompagnement les soutient donc également dans leur processus de subjectivation, en engageant pour certains adolescents une véritable réinsertion subjective / The object of this work of thesis is a reflection on the way the subject can build itself in the adolescence, with its disease. I leave the postulate that about is the somatic chronic disease, mechanisms would be common to all the teenagers confronted with this disease " since always there ". My research work leans on seven teenagers hospitalized in our unity care-studies. The process of subjectivation for these teenagers implies to compose with a " work of the disease ". A possible work of subjectivation of the parents as " parents of a sick child " can allow them not to find itself in dead end in their search for identity. It is a question for these teenagers of regaining control the history of their disease to provide subject future. After the burglary aroused by the disease arrives the puberty, one moment of physical changes which does not save the teenagers affected by a chronic disease, in spite of the fantasy of some patients in this connection. The sick body becomes a pubescent body with the disease and with the juvenile reorganizations. It seems necessary that a feeling of envelope " good enough " was able to establish during the childhood, to allow the teenager not to feel too much not secure. I meet the teenagers in a particular context: they are hospitalized for care, but also for their studies, and are thus separated from their family. The teenager makes a commitment from then on in an initiative of care, first step towards a demand of reflection to arrest better his disease and understand how to build itself with her. Our work of accompaniment also supports them thus in the process of subjectivation, by committing for certain teenagers a real subjective reintegration

Class/Act: Embodied Practices for Performative Pedagogy is a personal and practical exploration of embodiment’s role in higher education acting pedagogy. In my thesis, I propose that embodied acting practices rooted in phenomenology and corporeal dramaturgy surpass conventional acting curricula. Embodied training is often confused with movement curricula and is regularly considered a shallow and/or unintelligent means to approaching acting work. However, I will argue the efficiency and effectiveness of embodied teaching techniques in four parts. Part One: Seeing is a retrospective of how my personal experiences outside of the classroom have drawn me toward embodied aesthetics. Part Two: Knowing unveils my research of embodiment, its origins, and its impact on theatrical disciplines. Part Three: Being/Doing is an in-depth look into diverse schools of acting and how they fall short of fully embracing embodied practices. Part Four: Becoming is an introduction to my creation of an embodied business approach for actors called Professional Embodied Preparation (PEP) and continues the discussion of embodiment’s transformative influence and integration into the higher education curricula. Throughout the thesis, I hope to prove that embodied acting pedagogy is an essential tool for providing greater efficiency, proficiency, and auto-didacity for the pre-professional actor in the academic classroom and beyond.

The South West Botanical Province of Western Australia is one of the most floristically rich areas of the world with over, 8,000 species present, the majority of which (70%), are endemic to this region. Coupled with this high level of endemism, many taxa are threatened which makes them vulnerable to habitat alterations, modifications and destruction. Significant habitat alteration in many areas has resulted in 27 species becoming extinct in the South West Botanical Province, while an additional 327 species are classified as rare and endangered. In the context of stemming this loss of biodiversity, research in cryopreservation was undertaken to provide offsite protection and conservation of somatic germplasm.Cryostorage techniques were evaluated in this study to determine the key factors which may affect the ability of somatic tissues of Haemodoraceae species to survive, recover and grow following liquid nitrogen (LN) immersion and storage. Using Anigozanthos viridis as a comparator in most experiments, the base vitrification protocol was established, which involved: (1) preculturing shoot apices on 0.4 M sorbitol for 48 h; (2) incubation in a vitrification cryoprotective solution (PVS2) for 25 min at 0 degrees celsius; (3) LN immersion; (4) recovery to active growth through warming (immersion in a 40 degrees celsius water bath). Using this procedure the highest post-LN survival of shoot apices for A. viridis was 41.4 plus or minus 6.1% Four additional taxa were successfully cryopreserved with this base protocol (Anigozanthos manglesii, A. rufus, Conostylis wonganensis and A. rufus x A. pulcherrimus); a fifth taxon, Macropidia fuliginosa, however, proved unresponsive.To improve on post-LN survival, further research established that four of the six study taxa responded to the following amendments to the basic protocol: (1) longer preculture duration; (2) preculture on ++ / 0.8 M glycerol rather than sorbitol, (3) utilisation of PVS2 solutions with reduced DMSO content; and (4) incorporation of an additional loading phase (2 M glycerol plus 0.4 M sucrose for 20 mins at 0 degrees celsius).Macropidia fuliginosa, a species with poor recovery after LN exposure, was successfully cryostored using somatic embryos. Treatments which resulted in the highest survival (67.3% 5.7 plus or minus %) included preculture with 0.4 M sorbitol, and incubation in PVS2 for 30 min. Further experimentation indicated that preculture for two days on 0.8 M glycerol (replacing 0.4 M sorbitol) was more beneficial for achieving high post-LN survival.Post-LN survival was significantly correlated to the use of polyalcohols when the total number of hydroxyl (-OH) groups (regardless of molarity) present was the same as that found in 0.4 M sorbitol. It was hypothesised that hydroxyl number is more important than molarity in membrane stabilisation, during dehydration and cooling. Post-LN survival was also found to be significantly influenced by stereochemical arrangement of the -OH groups of polyalcohol molecules used in the preculture media. Finally, post-LN survival was also found to be significantly influenced by the size of the molecule, with smaller polyalcohols with more -OH groups on one flank of the carbon chain being superior as cryoprotective agents.The influence of plant growth regulators on post-LN survival and recovery growth was also investigated. The survival of shoot apices was not correlated to cytokinin or auxin treatments administered in culture media prior to cryostorage. However, in the recovery medium, a combination of cytokinin and 0.5 mu M GA(subscript)3 in the medium was found to be the most efficacious for obtaining healthy plantlets.Genetic fidelity was then examined using Amplified Fragment Length Polymorphism (AFLP). Plantlets of one done kept ++ / or maintained under the following conditions: (1) standard tissue culture conditions; (2) cold storage and (3) cryostorage, over a 12 month duration, showed no detectable genetic changes.Further, shoot apex viability evaluated at regular intervals (after 0, 3, 6 and 12 months of LN storage) suggested that medium term storage of samples cryopreservation did not reduce shoot apex viability over this time span.This study has provided a better understanding of the factors influencing post-LN survival and recovery and, as a result, the cryopreservation protocols have been refined. Consequently, the prospects for conserving threatened Haemodoraceae species from Western Australia through cryostorage is now significantly improved.

Typescript (photocopy) / xiii, 209 leaves : ill., (1 col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Genetics, 1983