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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.
21

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.
22

Discovery Islands, Earth Islands: The Theory and Practice of Island Imagery in Environmental Thought

Bosch, Naomi A 01 January 2015 (has links)
Earth Island is a core metaphor of activist thought often applied in Environmental Analysis and related fields as a tool for thinking about the planet’s limited resources. It puts forth the claim that if only we thought of the earth as more like an island, we would better understand our connectivity to other living things and be drawn to develop better and more extensive practices of environmental stewardship. This thesis uses personal accounts of environmental life philosophies and political practices collected from residents of the Discovery Islands in British Columbia as a site for analytical comparison between the theory and practice of "Earth Island." First providing an overview of the history of Earth Island and exploring existing Anthropology and Island Studies scholarship on island community dynamics and environmental perspectives, this thesis examines how the environmental relationships experienced by Discovery Islanders reflect or differ from the type of activist consciousness theoretically proposed by Earth Island. This creates a context for critically reflecting on the limits and applications of the Earth Island metaphor, and suggesting shifts in current approaches to the use of island imagery in environmental political and philosophical thought, promoting a focus on more community cooperation-oriented, less fatalistic themes.
23

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??).
24

Educación Rapa Nui : revitalización del idioma y cultura Ma'ori Rapa Nui

Tepano Martin, Ariki 03 1900 (has links)
SEMINARIO PARA OPTAR AL TITULO DE INGENIERO COMERCIAL, MENCIÓN CIENCIAS ECONOMICAS / Esta tesis analiza el Sistema de Educación instaurado en Rapa-Nui, y su rol en la revitalización del idioma y cultura local. El estudio parte visualizando los problemas del actual sistema educacional, con un análisis desde los mismos programas que se han desarrollado en las escuelas, junto con determinar las causas político, sociales y educacionales de la inminente perdida del manejo y uso del idioma rapa nui en la comunidad escolar y en general. Este trabajo se centra en justificar la educación de medio rapa nui y los cursos de inmersión, como pilar fundamental para avanzar en un sistema educacional propio, que se haga cargo de revitalizar el idioma rapa nui y su cultura. El análisis utiliza como ejemplo a seguir, dos experiencias internacionales exitosas en revitalización de idioma y cultura, el maorí y el hawaiano. El estudio termina con una discusión en materia de educación indígena, aterrizados a la realidad Rapa-Nui y la relación con las políticas educacionales del Estado de Chile, describiendo como debería ser el sistema educacional rapa nui, que hay que hacer para lograrlo, y que costos se deberían tomar en cuenta en grado de prioridad estratégica.
25

El Espacio Como Espejo Cultural. Reflexiones Ecocríticas en América Latina a Principios del Nuevo Milenio

Woolson, Maria Alessandra, Woolson, Maria Alessandra January 2014 (has links)
Esta disertación examina diversas expresiones artísticas y literarias de finales del siglo XX y principios del XXI desde una perspectiva ecocrítica. La tesis sostiene que la literatura contemporánea y el arte en general ofrecen experiencias por medio de las cuales se puede reconceptualizar lo que hoy se conoce como crisis medioambiental, para dar a conocer su dimensión ética y entenderla como una crisis moderna del conocimiento. Como una intersección de teoría crítica y estudios ambientales la ecocrítica ha abordado la dicotomía cultura-naturaleza como un dualismo cartesiano convencional. Este trabajo complejiza la dialéctica de sujeto y objeto, integrando perspectivas de la teoría poscolonial y los estudios de performance, y examina cómo la representación se apropia de espacios retóricos y epistémicos para intervenir en la percepción que el individuo tiene de la realidad. Del estudio surge un marco analítico que se identifica con la sustentabilidad y responde a tensiones sociales y culturales contemporáneas que se tejen entre el conocimiento local y las fuerzas globales. Mediante la inclusión de perspectivas acotadas de investigación, el estudio mantiene la referencialidad de las obras y permite plantear interrogantes sobre la naturaleza ontológica y epistémica de los estudios culturales. La tarea se aborda a lo largo de tres ejes: un análisis de las instalaciones de la escultora mexicana Helen Escobedo y de los artistas argentinos Nicolás García Uriburu y Marta Minujín, un examen de obras literarias -principalmente La loca de Gandoca de Anacristina Rossi (Costa Rica) y Un viejo que leía novelas de amor de Luis Sepúlveda (Chile)- y un trabajo de campo llevado a cabo con la comunidad Rapa Nui de Isla de Pascua (territorio chileno). Este último eje revela aspectos de una cosmovisión diferente, perteneciente a una identidad colectiva en búsqueda de reconocimiento dentro del mundo multicultural latinoamericano. La tesis concluye con un epílogo que analiza brevemente El libro del silencio de Ricardo Chávez Castañeda (México). A modo de síntesis, mediante juegos del lenguaje, esta novela expone la modernidad contemporánea como una crisis mucho mayor que se reproduce en múltiples dimensiones, donde el desequilibrio medioambiental se reconstituye en síntoma de una crisis de la civilización.
26

Absorción de agua y nutrientes y respuesta fisiológica de plantas halofitas y glicofitas bajo condiciones de estrés salino

Agudelo Sánchez, Agatha 29 November 2021 (has links)
Tesis por compendio / [ES] El incremento en la concentración de sales en suelos y agua es una de las problemáticas que más amenazan a la humanidad por su efecto directo sobre la productividad de las cosechas. En líneas generales la pregunta a la que queremos contribuir es ¿cómo enfrentarnos a una situación de salinización en un contexto de cambio climático y crecimiento demográfico? Más concretamente estudiamos la problemática en el sureste español desde un enfoque en que los resultados puedan ser explotados en el corto y medio plazo por el sector empresarial. La Región de Murcia es una de las principales zonas productoras del sureste español donde además existen graves problemas de salinización. En la presente tesis doctoral se propone utilizar aguas salinas para riego e investigar las implicaciones de ello a nivel de absorción de agua y nutrientes, estudiando también los cambios fisiológicos en la planta para obtener aplicaciones que permitan el crecimiento económico. En este sentido se abordan dos estrategias: por un lado, el estudio de plantas halofitas, y por otro, la bioestimulación en plantas glicofitas. La mayoría de los cultivos productivos son plantas glicofitas, ven afectadas sus producciones cuando hay elevadas concentraciones de sal en el medio de cultivo. Por el contrario, las plantas halofitas han desarrollado diferentes mecanismos para resistir los efectos negativos de la salinidad. Es por ello que la explotación directa de halofitas se ha identificado como una salida económica para las zonas afectadas. Otra forma de mitigación de los efectos del cambio climático es el desarrollo de la bioestimulación para incrementar la resistencia a estreses o para incrementar la concentración de compuestos bioactivos en los alimentos. Para los estudios realizados, se seleccionaron 6 especies vegetales que fuesen representativas de los diferentes comportamientos frente a la salinidad, que fuesen propias de la localización seleccionada (Región de Murcia) y de interés para la empresa promotora del proyecto de investigación (Sakata Seed Ibérica). Las especies estudiadas fueron: Brassica oleracea L., Brassica rapa L., Cakile maritima, Salicornia fruticosa y Atriplex halimus. El primer objetivo se centró en el análisis de los efectos de la salinidad sobre las especies objeto de estudio. Más concretamente intentando identificar rasgos que pudiesen servir para discriminar entre especies y/o cultivares las mejores respuestas a la salinidad. Por un lado, las interrelaciones entre distintos rasgos fisiológicos en respuesta a la salinidad se analizaron estadísticamente mediante un Discriminant Canonical Analysis (DCA), en el que se observó una relación entre el crecimiento y la suculencia de las hojas como medida de adaptación a la salinidad. Patrones como la acumulación de iones, el contenido en proteínas y ácidos grasos insaturados en respuesta a la salinidad pueden emplearse para discriminar entre distintas respuestas al estrés salino. Por otro lado, se estudió el efecto de la salinidad sobre la concentración y el perfil de glucosinolatos de distintos cultivares de brócoli (Brassica oleracea L.) en distintos periodos productivos. También se observó el efecto estimulador de los estreses como la temperatura y la salinidad sobre el perfil de glucosinolatos y la posibilidad de inducir complejos de glucosinolatos con fenólicos que no habían sido descritos previamente en Brassicales. El segundo objetivo se centró en la búsqueda de formas de explotación económica de las distintas respuestas fisiológicas. Por un lado, se desarrolló una metodología que permitió incrementar el contenido en glucosinolatos de las plantas de brócoli, sin que se viese en detrimento ni la producción ni los parámetros organolépticos del órgano comercial, lo cual fue posible mediante la aplicación de metil jasmonato y un polieter polisiloxano de forma foliar. Por otro lado, en las especies halofitas se analizó su aptitud par / [CA] L'augment de la concentració de sals en sòls i aigua és un dels problemes que més amenacen la humanitat pel seu efecte directe sobre la productivitat dels cultius. En termes generals, la qüestió a la qual volem contribuir és: com afrontar una situació de salinització en un context de canvi climàtic i creixement de la població? Més concretament, hem estudiat els problemes del sud-est d'Espanya des d'un enfocament en què els resultats poden ser explotats a curt i mitjà termini pel sector empresarial. La Regió de Múrcia és una de les principals zones productores del sud-est d'Espanya on també hi ha greus problemes de salinització. En aquesta tesi s'utilitzen aigües salines per al reg i s'investiguen les implicacions que això comporta a nivell d'absorció d'aigua i nutrients, estudiant també els canvis fisiològics en la planta per obtenir aplicacions que permetin el creixement econòmic. En aquest sentit s'aborden dues estratègies: d'una banda, l'estudi de les plantes d'halòfites i, de l'altra, la bioestimulació en plantes glicòfítes. La majoria dels cultius productius són plantes glicòfites, la seva produccions es veu afectada quan hi ha altes concentracions de sal en el medi de creiximent. Per contra, les plantes halófites han desenvolupat diferents mecanismes per resistir els efectes negatius de la salinitat. És per això que l'explotació directa d'halòfits s'ha identificat com una sortida econòmica per a les zones afectades. Una altra forma de mitigació dels efectes del canvi climàtic és el desenvolupament de bioestimulació per augmentar la resistència a estrès o augmentar la concentració de compostos bioactius en els aliments. Per als estudis realitzats en aquesta tesi doctoral es van seleccionar 6 espècies vegetals representatives dels diferents comportaments contra la salinitat, típics de la ubicació seleccionada (Regió de Múrcia) i d'interès per a l'empresa promotora del projecte de recerca (Sakata Seed Ibérica). Les espècies estudiades van ser: Brassica oleracea L., Brassica rapa L., Cakile maritima, Salicornia fruticosa i Atriplex halimus. El primer objectiu es va centrar en l'anàlisi dels efectes de la salinitat sobre les espècies objecte d'estudi. Més específicament tractant d'identificar trets que podrien servir per discriminar entre espècies i/o cultivars amb les millors respostes a la salinitat. D'una banda, les interrelacions entre diferents trets fisiològics en resposta a la salinitat van ser analitzades estadísticament per una Anàlisi Canònica Discriminant (DCA), en la qual s'observava una relació entre el creixement i la suculència de les fulles com a mesura d'adaptació a la salinitat. Patrons com l'acumulació d'ions, el contingut de proteïnes i àcids grassos insaturats en resposta a la salinitat es poden utilitzar per discriminar entre diferents respostes a l'estrès salí. D'altra banda, s'ha estudiat l'efecte de la salinitat en la concentració i perfil de glucosinolats de diferents cultius de bròquil (Brassica oleracea L.) en diferents períodes de producció. També vam observar l'efecte estimulant d'estrès com la temperatura i la salinitat en el perfil dels glucosinolats i la possibilitat d'induir complexos glucosinolatats amb fenòlics que no s'havien descrit prèviament en brassicales. El segon objectiu es va centrar en la recerca de formes d'explotació econòmica de les diferents respostes fisiològiques. D'una banda, es va desenvolupar una metodologia que permetia augmentar el contingut de glucosinolat de plantes de bròquil, sense perjudici ni de la producció ni dels paràmetres organolèptics de l'òrgancomercial, que va ser possible mitjançant l'aplicació de jasmonat de metil i un polieter de polisiloxà de forma foliar. D'altra banda, per a les espècies d'halòfits, es va realitzar una anàlisi per determinar la seva idoneïtat per a possibles usos tant culinaris com industrials. / [EN] The increase in the concentration of salts in soils and water is one of the problems that most threatens humanity due to its direct effect on crop productivity. In general terms, the question we want to contribute to is how to deal with salinization in the context of climate change and population growth? More specifically, we study the problems in south-eastern Spain from an approach in which the results can be exploited in the short and medium-term by the business sector. The region of Murcia is one of the main producing areas in south-eastern Spain where there are also serious salinization problems for various reasons. In this doctoral thesis, it is proposed to use saline water for irrigation and to investigate the implications that this entails at the level of water and nutrient absorption, also studying the physiological changes in the plant to obtain applications that allow economic growth. In this sense, two strategies are approached: on the one hand, the study of halophytic plants, and on the other hand, biostimulation in glycophyte plants. Most of the productive crops are glycophyte plants, their productions are affected when there are high concentrations of salt in the culture medium. On the contrary, halophyte plants have developed different mechanisms to resist the negative effects of salinity. That is why the direct exploitation of halophytes have been identified as an economic outlet for the salt-affected areas. Another way of mitigating the effects of climate change is the development of biostimulation to increase resistance to stresses or to increase the concentration of bioactive compounds in food. For the studies carried out in this doctoral thesis, 6 plant species were selected that were representative of the different behaviours towards salinity, that were specific to the selected location (The region of Murcia), and of interest to the company promoting the research project (Sakata Seed Ibérica). The species studied were: Brassica oleracea L., Brassica rapa L., Cakile maritima, Salicornia fruticosa, and Atriplex halimus. The first objective of this thesis focused on the analysis of the effects of salinity on the species understudy. More specifically trying to identify traits that could serve to discriminate between species and/or cultivars that best respond to salinity. Moreover, the interrelationships between different physiological traits in response to the salinity were statistically analysed using a Discriminant Canonical Analysis (DCA), in which a relationship between growth and succulence of the leaves were observed as a measure of adaptation to salinity. Patterns such as ion accumulation, protein content, and unsaturated fatty acids in response to salinity can be used to discriminate between different responses to salt stress. On the other hand, the effect of salinity on the concentration and profile of glucosinolates of different cultivars of broccoli (Brassica oleracea L.) indifferent productive periods were also studied. The stimulating effect of stresses such as temperature and salinity on the glucosinolate profile and the possibility of inducing glucosinolates with phenolics complexes that had not been previously described in Brassicales were also observed. The second objective focused on the search for forms of economic exploitation of the different physiological responses. On the one hand, a methodology was developed that allowed increasing the glucosinolate content of broccoli plants, without affecting the production or any organoleptic parameter of the commercial organ. This was possible through the application of methyl jasmonate and a polyether polysiloxane in foliar form. On the other hand, for the halophyte species, an analysis was carried out to determine their aptitude for possible culinary and industrial uses. / This work was funded by the Spanish Ministerio de Ciencia, Innovación y Universidades (AGL2016-80247-C2-1-R and RTC-2015-3536-2). / Agudelo Sánchez, A. (2021). Absorción de agua y nutrientes y respuesta fisiológica de plantas halofitas y glicofitas bajo condiciones de estrés salino [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/177647 / TESIS / Compendio
27

Road my body goes: re-creating ancestors from stone at the great moai quarry of Rano Raraku, Rapa Nui (Easter Island)

Richards, C., Croucher, Karina, Paoa, T., Parish, T., Tucki, E., Welham, K. January 2011 (has links)
No / Recognizable throughout the world, the stone statues (moai) of Rapa Nui (Easter Island) represent the largest monolithic architecture produced in Polynesia. The exquisitely carved and finished head and torso of each statue testifies to a skill in stone carving and dressing unmatched throughout the Pacific. Yet, approximately one thousand ‘classic’ statues were produced at the quarries within a few hundred years. What was the ritual status of the quarry and the labour necessary to produce the numbers of statues that allowed Heyerdahl to declare that the ‘whole mountain massif has been reshaped, the volcano has been greedily cut up’ (1958: 83)? What was it like to go to work at Rano Raraku? By drawing on a range of evidence we argue that walking to and labouring at Rano Raraku represented a spatial and temporal journey to a place of highly dangerous forces, a cosmogonic centre where prehistoric Rapa Nui people came face to face with their ancestors and the Polynesian gods.
28

The Effects of Coal Dust Particulates on Growth Performance and Photomorphogenic Responses of Brassica Rapa

Elam, Robert J. January 2017 (has links)
No description available.
29

Effects of light intensity and nitrogen source on pac choi (Brassica rapa l.), and interaction with the diamondback moth (Plutella xylostella l.).

Johnson, Wendy Ann January 1900 (has links)
Doctor of Philosophy / Department of Entomology / Raymond A. Cloyd / James R. Nechols / Raymond A. Cloyd / James R. Nechols / Greenhouse studies were conducted to examine direct effects of light intensity and nitrogen source on primary and secondary metabolism of pac choi (Brassica rapa L. var. chinensis cv. ‘Mei Qing Choi’) and indirect effects on diamondback moth (Plutella xylostella L.)(DBM). In the first study, plants were exposed to high and low light intensities during different times of the year, resulting in a range of light intensities. From four experiments, plants exhibited higher phenolic content, greater shoot biomass, and higher C:N ratios under high light intensity, whereas plants under low light intensity contained higher protein. Ferulic acid increased under high light intensity, and this increase was negatively correlated with male DBM body weights. However, DBM developed faster on plants in the August experiment (high light), compared to the July experiment (lower light). This implies that light intensity may not be affecting DBM through plant-mediated changes unless reduced male weights confer a reduction in larval consumption. In the nitrogen source study, application of an organic source of nitrogen (fish hydrolysate fertilizer) was compared to a conventional fertilizer to determine whether nitrogen source directly impacts pac choi chemistry and biomass, thus indirectly impacting DBM fitness. In two experiments, there was no significant effect of fertility treatment on pac choi nutrients or biomass, with the exception of percent leaf phosphorus, which was significantly higher in the conventional fertility treatment. For DBM, percent survival and cohort development were significantly reduced on pac choi receiving the organic fertilizer. Calcium and magnesium were significantly higher in pac choi infested with DBM larvae than plants without DBM. In addition, calcium was negatively correlated with female DBM body weights in one experiment for the organic treatment. Overall, this study demonstrated that pac choi plants that received the organic fertilizer were similar to pac choi plants that received a conventional fertilizer with the exception of phosphorus. Furthermore, female DBM body weights were negatively impacted by calcium in the organic treatment. As multiple fitness traits for DBM were negatively affected in the organic treatment, pac choi crops grown with fish hydrolysate fertilizer may experience less feeding from DBM.
30

Nitrate-nitrogen sufficiency ranges in leaf petiole sap of pac choi grown with organic and conventional fertilizers

Elfar Altamimi, May January 1900 (has links)
Master of Science / Department of Horticulture, Forestry, and Recreation Resources / Rhonda R. Janke / Petiole sap nitrate-nitrogen (NO3-N) analysis with handheld meters is a valuable tool in applying in-season nitrogen (N) for many crops. Sufficiency levels have been determined for several leafy green crops, including lettuce (Lactuca sativa L.) and cabbage (Brassica oleracea L.), but not for pac choi (Brassica rapa L.). The response of pac choi to different fertilizer rates and sources [conventional and organic] has established optimal soluble N application rates and Cardy meter sufficiency ranges. Greenhouse experiments were conducted during summer and fall of 2008 in Manhattan, KS. Conventional soluble fertilizer was formulated from inorganic salts with a 4 NO3-N: 1 ammonium ratio. Phosphorus was held at 1.72mM and K at 0.83mM for all treatment levels. The organic soluble fertilizer, fish hydrolyzate (2N:1.72P:0.83K), was diluted to provide the same N levels as with conventional treatments. Both fertilizers were applied at rates of 0, 32, 75, 150, 225, 300, and 450 mg. L-1. Seedlings were transplanted and fertilizer application began at 18 days. Plants were harvested at seven weeks (five weeks post transplanting) after receiving 15 fertilizer applications during production. Samples of the most recently matured leaves were harvested weekly and analyzed for petiole sap NO3-N and leaf blade total N concentration. Leaf count, leaf length, and chlorophyll content were also measured weekly. Fresh and dry weights were determined on whole shoots and roots. Optimum yield was achieved at the 150 mg. L-1 fertility rate with both conventional and organic fertilizers. Field and high tunnel experiments were conducted during fall 2008 to validate the sufficiency ranges obtained from the greenhouse studies. Based on field and high tunnel results, sufficiency levels of NO3-N for pac choi petiole sap during weeks 2 to 3 of production were 800-1500 mg. L-1, and then dropped to 600-1000 mg. L-1 during weeks 4 through harvest for both conventional and organic fertilizers sources. These ranges could vary based on the variety of the crop, the fertility of soil, and certain environmental factors such as photoperiod, light intensity. However, we found that petiole sap nitrate always increased to the point associated with the maximum biomass, followed by a plateau where sap nitrate remained constant. This characteristic of the Cardy meter can provide the growers with a practical methodology to generate their standard curves under specific conditions to guide in-season N applications. Total N in leaf tissue showed fewer fertilizer rate effects than petiole sap NO3-N. Chlorophyll content was not useful in evaluating pac choi N status.

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