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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

El impacto de la modernidad sobre la población juvenil actual de Isla de Pascua.

Valera Pérez, Rubén January 2004 (has links) (PDF)
La memoria de título que se presenta a continuación tiene como fin principal entregar un diagnóstico actualizado de la situación en la cual se encuentra la población juvenil autóctona de Isla de Pascua, luego del impacto que ha significado el proceso de modernización para esta isla y su población en los últimos treinta años aproximadamente. Lo que se ha traducido en la indagación y posterior entrega de antecedentes sobre aspectos tales como: percepciones sobre la pérdida o revitalización de la identidad cultural, aspiraciones de futuro de los jóvenes isleños, problemas y conflictos que enfrenta la juventud local en la actualidad, percepciones sobre la posible “Autonomía del pueblo rapa nui”, nivel de integración sociocultural hacia la vida moderna continental y nivel de autoestima étnica. Fundamentalmente, este diagnóstico tiene como base el propio discurso entregado por los diferentes jóvenes isleños que participaron en forma voluntaria de la investigación llevada a cabo y además se incorporaron las impresiones entregadas por las tres principales autoridades isleñas locales en torno al fenómeno abordado: Alcalde, Gobernador Provincial y Presidente del Consejo de Ancianos.
12

Påsköns stenstatyer, moai : Vilket genus representerar de? / Easter Island stonestatues, moai : What gender do they represent?

Dahlstrand, Ivan January 2008 (has links)
<p>Abstract.</p><p>The question in this analysis is which gender moai, the big statues on Rapa Nui, represent. My hypothesis is that they have developed from visual symbols to metaphores in mythologies from an polynesian context. That these statues were symbols for human origin and creation of ancestors ideological power, and gods in consideration male gender. In the long isolation, in both time and space, the mytologies in Rapa Nui was changed, and the pictures got a new meaning. These changes depended on clearing of wood and big trees and the following difficult situation in farming. It led to difficult exposure to climatchanges and much more hard work in the cultivation. This happened in the same time as rapanuis life became more dependent on what the earth could producece because of bad fishing and a growing population. The cult of fertility get a more central place in rapanuis religious life. The male metaphore changes to female when the mother of earth, papa, became the most important spiritual force concerning food supply. I mean that moai follow the mythologies change, and developed in both form, size and contents. The theories behind this discussion is the analysis of Karen Armstrong, in how mythologhies change when human go from hunting- to cultivating society, and where she explain how the gender of gods changes from male to female. I also use theories from structuralism that say that human thinking and building mythologies follow an arcetypical pattern, for us to make our world understandable and organized. This analysis, and changed interpretation of moai from male to female representation, is a critical studie of traditional interpretation to “primitiv” art from aborigines and prehistorical humans. I mean the common interpretation of prehistorical pictures in Rapa Nui have a basic europeen code where an abstract male is standard. My theoretical support here is the analysis of Yvonne Hirdmans of gender from a historical perspective. The most important sources I have use in this work comes from archaeology, ethnology and art analythic work on Rapa Nui, with litterature from Jo Anne Van Tilburg, Georgia Lee and more scientist search from the island. I have also made field studies of my own. I hope this analys can contribute toward a critical view of a stereotypical european norm in interpretation of “primitive” and prehistorical art.</p>
13

Påsköns stenstatyer, moai : Vilket genus representerar de? / Easter Island stonestatues, moai : What gender do they represent?

Dahlstrand, Ivan January 2008 (has links)
Abstract. The question in this analysis is which gender moai, the big statues on Rapa Nui, represent. My hypothesis is that they have developed from visual symbols to metaphores in mythologies from an polynesian context. That these statues were symbols for human origin and creation of ancestors ideological power, and gods in consideration male gender. In the long isolation, in both time and space, the mytologies in Rapa Nui was changed, and the pictures got a new meaning. These changes depended on clearing of wood and big trees and the following difficult situation in farming. It led to difficult exposure to climatchanges and much more hard work in the cultivation. This happened in the same time as rapanuis life became more dependent on what the earth could producece because of bad fishing and a growing population. The cult of fertility get a more central place in rapanuis religious life. The male metaphore changes to female when the mother of earth, papa, became the most important spiritual force concerning food supply. I mean that moai follow the mythologies change, and developed in both form, size and contents. The theories behind this discussion is the analysis of Karen Armstrong, in how mythologhies change when human go from hunting- to cultivating society, and where she explain how the gender of gods changes from male to female. I also use theories from structuralism that say that human thinking and building mythologies follow an arcetypical pattern, for us to make our world understandable and organized. This analysis, and changed interpretation of moai from male to female representation, is a critical studie of traditional interpretation to “primitiv” art from aborigines and prehistorical humans. I mean the common interpretation of prehistorical pictures in Rapa Nui have a basic europeen code where an abstract male is standard. My theoretical support here is the analysis of Yvonne Hirdmans of gender from a historical perspective. The most important sources I have use in this work comes from archaeology, ethnology and art analythic work on Rapa Nui, with litterature from Jo Anne Van Tilburg, Georgia Lee and more scientist search from the island. I have also made field studies of my own. I hope this analys can contribute toward a critical view of a stereotypical european norm in interpretation of “primitive” and prehistorical art.
14

Komari-motiv på Rapa Nui (Påskön) : Diskursanalys över akademiska forskningstexter om Komari / Komari-motifs on Rapa Nui (Easter Island) : Discourse Analysis ofacademic research regarding Komari

Melin, Wilda January 2023 (has links)
Denna uppsats syftar till att kritiskt undersöka de akademiska diskurserna kring den symboliska tolkningen av förhistoriska Komari-motiv på Rapa Nui (Påskön). Genom att undersöka ett antal olika källor kommer uppsatsen att ge en översiktlig genomgång av de aktuella akademiska diskurserna samt diskutera de olika tolkningarna av symboliken hos komari-motiven. Genom att kombinera diskursanalys med ett feministiskt arkeologiskt perspektiv och ett postkolonialt perspektiv är huvudsyftet med uppsatsen att bedöma i vilken utsträckning den sociala konstruktionen av kön och sexualitet samt koloniala idéer har påverkat tolkningarna av symbolerna. / This essay aims to critically examine the academic discourses surrounding the symbolic interpretation of prehistoric Komari-motifs in Rapa Nui (Easter Island). The analysis will draw on a variety of sources and will give a brief overview of the academic discourses in question and discuss the different interpretations of the symbolism behind the komari-motifs. Combining discourse analysis with a feminist archaeology perspective and a postcolonial perspective, the main aim of the essay is to assess to what extent the social construction of gender, sexuality and colonialist ideas influenced the development of theories regarding the symbols.
15

The role of calcium and potassium in salinity tolerance in Brassica rapa L. cv. RCBr seed

Collins, R. P. January 2012 (has links)
The possibility of manipulating calcium (Ca2+) and potassium (K+) levels in seeds of Brassica rapa by altering parent plant nutrition and investigating the potential for increased salinity tolerance during germination, given that considerable amounts of literature imply that greater amounts of available exogenous Ca2+ and K+ can ameliorate the effects of salinity on both whole plant growth and germination, was evaluated. The investigation consisted of four growth trials. Two preliminary growth trials suggested that seed ion manipulation was possible without affecting the overall growth and vigour of the plant. After developing suitable high and low Ca2+ and K+ nutrient solutions for growth, a trial was carried out in a growth room and greenhouse, with various substrates and the seed of a certain size category was collected for subsequent ion and salinity tolerance analysis. Seed Ca2+ and K+ was significantly affected by growth substrate and nutrient solution and data showed that a significant negative regression relationship existed between seed Ca2+, K+ and Ca2+ + K+ levels and salinity tolerance. Further experimentation using hydroponic culture attempted to remove any possible effects of substrate and also to compare size categories of seed with a view to elucidating localisation of Ca2+ and K+. Seed Ca2+ was found to be significantly altered by nutrient solution in the two different sizes tested and higher Ca2+ nutrient solution was found to increase salinity tolerance in daughter seed. One significant negative regression correlation between salinity tolerance and seed K+ concentration existed in smaller seed, but disregarding seed size in a regression analysis of seed ion content and salinity tolerance, a significant negative relationship existed between seed Ca2+, K+ and Ca2++ K+. The results, especially in terms of Ca2+ nutrition, contradict much previous research that suggests increased salinity tolerance at germination can arise with the increased presence of Ca2+ and/or K+. Salinity tolerance was greater in seeds of larger size across all nutritional treatments and the smaller size range exhibited increased Ca2+ and K+ per μg seed. Ca2+ concentration in smaller seeds with greater surface area:volume ratios provided a clue to the potential localisation of Ca2+. Cross sectional staining showed that a greater proportion of seed Ca2+ may reside in the coat. This was confirmed by analysis which showed an approximate 50% split of total extractable seed Ca2+, regardless of size, between coat and embryo within a seed; the majority of which, per μg, resides in the coat. Further work looked at the relative solubility of the Ca2+ and K+ in these tissues and whole seed to look at the potential bioavailability of Ca2+ during germination from various parts of the seed. Most water soluble Ca2+ exists in the embryo and most insoluble Ca2+ exists in the coat, but coat Ca2+ was found to be ionically exchangeable and therefore bioavailable. K+ appeared mostly water soluble in embryo and coat. In line with previous whole plant research in this species, most Ca2+ is readily water soluble or ionically exchangeable in form and the possible negative effects of how increasing bioavailable Ca2+ may reduce salinity tolerance was discussed.
16

When home is the navel of the world: an ethnography of young Rapa Nui between home and away

Andreassen, Olaug Irene Rosvik, Social Sciences & International Studies, Faculty of Arts & Social Sciences, UNSW January 2008 (has links)
Rapa Nui (Easter Island) has for centuries been known as an isolated island of archaeological mysteries; yet after a rapid modernisation this is today an international tourist destination, a World Heritage Site and a glocalised community. This anthropological study based on long-term fieldwork among young Rapa Nui on the island and away, describes how it can be to grow up in and to belong to such a place. Place is seen as a continually constructed social space and is influenced by Miriam Kahn??s use of Henri Lefebvre??s concept thirdspace. Rapa Nui, as a place, people and community, is here understood as continuously formed by global and local influences. Thus, although historical, global and national influences can seem overwhelming in such a small tourist destination with a turbulent colonial history, this study also sees the opinions and practices of the inhabitants as important agents. This thesis shows how young Rapa Nui are both influenced by and influencing what Rapa Nui is and becomes. Above all, their guiding principle seems to be a continuing strong attachment to their land ??also called Te Pito o te Henua (??The Navel of the World??).
17

Development of molecular markers for marker assisted selection for seed quality traits in oilseed rape

Rahman, Md. Mukhlesur 28 September 2007 (has links)
Molecular markers for seed quality traits including erucic acid content genes, seed coat color genes in Brassica napus and seed coat color genes in B. rapa were developed. A single base change in the Bn-FAE1.1 gene in the A genome and a two-base deletion in the Bn-FAE1.2 gene in the C genome produce the nearly zero content of erucic acid observed in canola. The single base change was detected as single nucleotide polymorphic (SNP) marker with an ABI SNaPshot kit. A multiplexing primer set was designed by adding a polyT to the 5´ primer end to increase SNP detection throughput through sample pooling. The two-base deletion in the C genome gene was detected as a sequence characterized amplified region (SCAR) marker in an ABI 3100 Genetic analyzer. To increase the throughput, one genome specific primer was labeled with four fluorescence dyes and combined with 20 different primers to produce PCR products with different fragment sizes. These multiplexed high throughput molecular markers have been successfully implemented in our canola/rapeseed breeding programs. Trigenic inheritance was observed for seed coat color in B. napus. Three Sequenced Related Amplified Polymorphism (SRAP) markers very closely linked to the three different seed coat color genes were developed. Chromosome-walking technology was used to convert the SRAP marker into a SCAR marker and a SNP marker. Subsequently, the first seed coat color gene (Bn1) marker was converted into a SCAR marker, and the second seed coat color gene (Bn2) marker was converted into a SNP marker. Digenic inheritance was observed for seed coat color genes in B. rapa. A SRAP marker was identified as being tightly linked to the major seed coat color gene (Br1). The SRAP marker was sequenced and extended sequences were obtained using chromosome-walking technology. The flanking sequences of the SRAP marker contained 24 SNPs and a 12-bp deletion position that allowed the marker to be converted into a co-dominant SNP marker and a co-dominant SCAR marker, respectively. The SCAR marker was detected in the ABI 3100 genetic analyzer with four fluorescently labeled M13 primers integrated with different SCAR primers, which permitted pooling of PCR samples for high throughput detection. / October 2007
18

Production of synthetic genotypes of <i>Brassica juncea</i> via somatic and sexual hybridization

Campbell, Craig Thomas 01 January 1993 (has links)
The major objective of this study was to produce synthetic genotypes of Brassica juncea from its parental species <i> B. rapa </i> and <i> B. nigra </i> via somatic and sexual hybridization. As prerequisites for somatic hybridization experiments, methods were developed to improve the culture of mesophyll and hypocotyl protoplasts of <i> B. nigra </i> and <i> B. rapa </i>, to obtain reliable plant regeneration from mesophyll protoplast cultures of <i> B. nigra </i>, and to fuse protoplasts of <i> B. nigra </i> and <i> B. rapa </i>. A modified Kao's medium (1977), was found suitable for the culture of mesophyll protoplasts of <i> B. nigra </i> and <i> B. rapa </i>. At a density of approximately $110\sp5$ protoplasts/ml within a culture plate insert surrounded by culture medium, mesophyll protoplast cultures of <i> B. nigra </i> accessions R890, R1819, R3392 and U1218 and <i> B. rapa </i> cvs. R500 and Wong Bok formed colonies. Genotypic differences in cell division and colony formation were observed. Hypocotyl protoplasts of <i> B. nigra </i> and <i> B. rapa </i> were successfully isolated from 6 day-old seedlings cultured in a modified Kao's medium (1977). With <i> B. nigra </i> accession R890 and <i> B. rapa </i> cv. R500, cell division and colony formation were optimal when hypocotyl protoplasts were cultured at a density of 0.5 to $1.010\sp5$ protoplasts/ml within a culture plate insert surrounded by a nurse culture of 4 to 6 day-old mesophyll protoplasts of <i> B. nigra </i>. Plant regeneration was obtained from mesophyll protoplast-derived calli of <i> B. nigra </i> accession R890 originally cultured in inserts; a shoot regeneration frequency of 8.1% was obtained on a medium containing the salts and vitamins of medium K3 (Nagy and Maliga 1976) with 3 g/l sucrose, 18.2 g/l mannitol, 2 mg/l ZR, 0.1 mg/l NAA, 10 g/l agarose, pH 5.6. For somatic hybridizatian studies, methods were developed to select out parental protoplasts using iodoacetic acid and to efficiently fuse protoplasts on the bottom of a petri dish using PEG. Twenty-nine plants were recovered from fusion experiments between mesophyll protoplasts of <i> B. nigra </i> accession R890 and hypocotyl protoplasts of <i> B. rapa </i> cv. Tobin. The somatic hybrid plants resembled natural <i> B. juncea </i>, had $2n=36$ chromosomes and had pollen viabilities ranging from 30 to 45%. Twenty-one plants, derived from one callus colony, possessed the mitochondrial and chloroplast genomes of <i> B. rapa </i>, as found in natural <i> B. juncea </i>. Eight plants, derived from another callus, had a novel cytoplasmic combination consisting of the mitochondrial genome of <i> B. rapa </i> and the chloroplast genome of <i> B. nigra </i>. Synthetic genotypes of <i> B. juncea </i> were also produced from reciprocal sexual crosses between <i> B. rapa </i> and <i> B. nigra </i>. Seventy-eight interspecific hybrid plants from the cross <i> B. rapa </i> x <i> B. nigra </i> and six hybrid plants from the reciprocal cross were identified by their morphology, pollen viability and chromosome number. The colchicine-induced allotetraploids resembled natural <i> B. juncea </i> in morphology, had 18 bivalents at metaphase I, and had between 35 and 70% pollen viability.
19

Development of molecular markers for marker assisted selection for seed quality traits in oilseed rape

Rahman, Md. Mukhlesur 28 September 2007 (has links)
Molecular markers for seed quality traits including erucic acid content genes, seed coat color genes in Brassica napus and seed coat color genes in B. rapa were developed. A single base change in the Bn-FAE1.1 gene in the A genome and a two-base deletion in the Bn-FAE1.2 gene in the C genome produce the nearly zero content of erucic acid observed in canola. The single base change was detected as single nucleotide polymorphic (SNP) marker with an ABI SNaPshot kit. A multiplexing primer set was designed by adding a polyT to the 5´ primer end to increase SNP detection throughput through sample pooling. The two-base deletion in the C genome gene was detected as a sequence characterized amplified region (SCAR) marker in an ABI 3100 Genetic analyzer. To increase the throughput, one genome specific primer was labeled with four fluorescence dyes and combined with 20 different primers to produce PCR products with different fragment sizes. These multiplexed high throughput molecular markers have been successfully implemented in our canola/rapeseed breeding programs. Trigenic inheritance was observed for seed coat color in B. napus. Three Sequenced Related Amplified Polymorphism (SRAP) markers very closely linked to the three different seed coat color genes were developed. Chromosome-walking technology was used to convert the SRAP marker into a SCAR marker and a SNP marker. Subsequently, the first seed coat color gene (Bn1) marker was converted into a SCAR marker, and the second seed coat color gene (Bn2) marker was converted into a SNP marker. Digenic inheritance was observed for seed coat color genes in B. rapa. A SRAP marker was identified as being tightly linked to the major seed coat color gene (Br1). The SRAP marker was sequenced and extended sequences were obtained using chromosome-walking technology. The flanking sequences of the SRAP marker contained 24 SNPs and a 12-bp deletion position that allowed the marker to be converted into a co-dominant SNP marker and a co-dominant SCAR marker, respectively. The SCAR marker was detected in the ABI 3100 genetic analyzer with four fluorescently labeled M13 primers integrated with different SCAR primers, which permitted pooling of PCR samples for high throughput detection.
20

Differential Expression of Isopentenyl Transferase and Cytokinin Oxidase/Dehydrogenase During Pod and Seed Development in Brassica

O'Keefe, David John January 2012 (has links)
Consistency of yield and quality of seed are traits not yet optimised by the brassica seed industry in New Zealand. As of 2008, seed producers in Canterbury, New Zealand, exported approximately $18m of brassica seed. However, there is a need to increase both seed quantity and/or quality. The plant hormone group, the cytokinins, regulates many stages of plant growth and development, including cell division and enhancement of sink strength, both of which are important processes in seed development and embryonic growth. The two gene families targeted in this project play a key role in maintaining cytokinin homeostasis. Isopentenyl transferase (IPT) catalyzes the rate limiting step in the formation of cytokinins, and cytokinin oxidase/dehydrogenase (CKX) irreversibly inactivates cytokinins. The aim of this project was to identify those cytokinin gene family members expressing specifically during the early phases of pod and seed development. Initially this study used a rapid-cycling Brassica rapa (RCBr) because of its rapid life cycle, then, as the project developed, a commercial crop of forage brassica (B. napus) was studied. Reverse transcriptase PCR (RT-PCR) and BLAST analysis was used to identify putative IPT and CKX genes from RCBr and B. napus. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) was used to measure the expression of individual gene family members during leaf, flower, pod and seed development. BrIPT1, -3, and -5, and BrCKX1, -2, -3, and -5/7 and were shown to express differentially both temporally and spatially within RCBr root, stem, leaf, seed, and pod tissues. BnIPT1, 3 and 7 and BnCKX1, 2, 5 and 7 were also differentially expressed. Particularly strong expression was shown by BrIPT3, BrIPT5 and BrCKX2 in developing seeds. Both Brand BnIPT3 expressed strongly in maturing leaves. In normal plant growth and development, biosynthesis and metabolism of cytokinin is tightly regulated by the plant. Increasing the levels of cytokinins during seed development, either by over expressing IPT3 or IPT5, or decreasing the expression of CKX2, or both, could potentially increase both seed yield and seed vigour.

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