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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

Estudo de dois grupos de elementos de cana-de-açúcar homológos à superfamília hAT de transposons / Studies on hAT-like transposases in sugarcane superfamily

Jesus, Erika Maria de 18 June 2007 (has links)
Os elementos de transposicão (TEs) são sequências genéticas móveis. Sua capacidade mutagênica faz deles uma importante fonte de variabilidade nos genomas. Outro importante papel dos TEs na evolução dos genomas é o de doadores de domínios protéicos na formação de novos genes. 276 clones de cDNA homólogos a TEs foram previamente identificados no banco de dados do SUCEST (projeto de sequenciamento de etiquetas expressas de cana-de-acúcar). Neste trabalho nós realizamos o sequenciamento completo de 156 destes clones e a classificação e caracterização de suas sequências comparando-as com bancos de dados. Foram identificadas 9 diferentes famílias de transposons e 11 diferentes famílias de retrotransposons. As famílias mais representadas entre os transposons foram MuDr e hAT (que engloba os elementos do tipo Ac e Tam3), para os quais foram identificados 43 e 32 clones de cDNA, respectivamente. Entre os retrotransposons, a família mais representada foi Hopscotch, apresentando 25 clones de cDNA. Após esta análise global, o foco das investigações voltou-se para os cDNAs do tipo hAT. Uma análise comparativa destes cDNAs revelou que as sequências homólogas a hAT estão distribuídas em dois grupos. O grupo I, é composto por sequências com alta conservação no nível de nucleotídeos, está presente no genoma de todas as gramíneas analisadas (híbridos e parentais da cana-de-acúcar, milho e arroz) com um baixo número de cópias, teve a sua expressão detectada em folhas, raízes e mais intensamente em calos cana. Além disso, apresenta alta similaridade de sequências com transposases domesticadas descritas na literatura. O grupo II, por sua vez, é composto por sequências mais heterogêneas, que apresentam similaridade com os transposons originais que constituem a superfamília hAT: hobo (de Drosophila melanogaster), Ac (de Zea mays) e Tam3 (de Antirrhinum majus). Sua distribuição é restrita ao genoma de Saccharum, com um número de cópias maior que o grupo I. Um ensaio de PCR-Inversa identificou terminações inversas repetidas (TIRs) para o cDNA TE221 do grupo II. A partir de iniciadores desenhados sobre estas TIRs foi possível recuperar dois elementos, de 3,5kb e 4,2kb, respectivamente, e um MITE de 250 pb, todos homólogos a hAT. Este resultado demonstrou que a estratégia utilizada para recuperar elementos do genoma da cana-de-açúcar a partir do cDNA TE221 mostrou-se eficiente. Homólogos aos grupos I e II de cana-de-acúcar foram identificados em bancos de dados de milho, arroz e arabidopsis. Estes dados sugerem que a separação dos dois grupos ocorreu antes da divergência entre as classes Monocotiledonea e Eudicotiledonea. Com base nos resultados aqui apresentados sugerimos que um transposon ancestral do tipo hAT, presente nas angiospermas anteriormente à separação de Monocotiledonea e Eudicotiledonea, teve sua transposase capturada na formação de um gene com função celular. A partir do evento da domesticação, estas transposases seguiram dois caminhos evolutivos distintos, um como gene funcional e outro como um transposon tradicional. Estas duas formas de transposase do tipo hAT podem ser encontradas no genoma da cana-de-acúcar, representadas pelos elementos dos grupos I e II, respectivamente. / Transposable elements (TEs) are mobile genetic sequences. Their mutagenic capacity makes them important sources of variation in the genomes. These elements have another important evolutionary role as donors of functional protein domains in the formation of new genes. 276 cDNA clones homologous to TEs were previously identified in the Brazilian Sugarcane Expressed Sequence Tag Project (SUCEST) databases. In this work, we have obtained the full sequences of 156 for these clones. These sequences were compared with Genbank database. We have identified 9 families of transposons and 11 families of retrotransposons. The most representative families found amongst the transposons were MuDr and hAT (wich encompass Ac and Tam3), with 43 and 32 cDNAs, respectively. Amongst the retrotransposons, the most representative family was Hopscotch, with 25 cDNAs. After this global analysis, we have focused our investigation in the hAT-like cDNAs. A comparative analysis of these cDNAs has revealed a profile of two distinct groups. Group I is composed of sequences with high conservation at nucleotide level, it is present in the genome of all grasses analysed (hybrids and parentals of sugarcane, maize and rice) with low copy number, it is expressed in leaves and roots of sugarcane, and more intensely in callus. In addition, group I sequences have clustered with domesticated transposases. The group II is composed of more heterogeneous sequences similar with the original elements that constitute the hAT superfamily: hobo (from Drosophilla melanogaster), Ac (from Zea mays) and Tam3 (from Antirrhinum majus). This group was shown to be restricted to the genome of Saccharum, with higher copy number than group one. Inverse-PCR assays has identified terminal inverted repeats (TIRs) to the cDNA TE221 from group II. Primers based on the sequences of the TIRs allowed us to recover three elements hAT-like from sugarcane’s genomic DNA: one of 3,5kb and another of 4,2kb, and a MITE of 250 bp. These results corroborate the strategy applied in order to recover elements from the sugarcane´s genome. Sequences homologous to both sugarcane group I and group II were found also in maize and rice, as well as in arabidopsis databases. These data suggest that the divergence of the two groups occured before the separation between the classes Monocotiledonea and Eudicotiledonea. Based on our results, we suggest the existence of an ancestral transposon hAT-like, present in angiosperms before the separation between Monocotiledonea and Eudicotiledonea, of which the transposase was captured to compose a new gene with some cellular function. Since the domestication event, these transposases followed distinct evolutive pathways, one as a regular gene and another as a bona fide transposon. These two forms of hAT-like transposases could be found in the sugarcane’s genome, represented by the elements from groups I and II, respectively.
12

Estudo de dois grupos de elementos de cana-de-açúcar homológos à superfamília hAT de transposons / Studies on hAT-like transposases in sugarcane superfamily

Erika Maria de Jesus 18 June 2007 (has links)
Os elementos de transposicão (TEs) são sequências genéticas móveis. Sua capacidade mutagênica faz deles uma importante fonte de variabilidade nos genomas. Outro importante papel dos TEs na evolução dos genomas é o de doadores de domínios protéicos na formação de novos genes. 276 clones de cDNA homólogos a TEs foram previamente identificados no banco de dados do SUCEST (projeto de sequenciamento de etiquetas expressas de cana-de-acúcar). Neste trabalho nós realizamos o sequenciamento completo de 156 destes clones e a classificação e caracterização de suas sequências comparando-as com bancos de dados. Foram identificadas 9 diferentes famílias de transposons e 11 diferentes famílias de retrotransposons. As famílias mais representadas entre os transposons foram MuDr e hAT (que engloba os elementos do tipo Ac e Tam3), para os quais foram identificados 43 e 32 clones de cDNA, respectivamente. Entre os retrotransposons, a família mais representada foi Hopscotch, apresentando 25 clones de cDNA. Após esta análise global, o foco das investigações voltou-se para os cDNAs do tipo hAT. Uma análise comparativa destes cDNAs revelou que as sequências homólogas a hAT estão distribuídas em dois grupos. O grupo I, é composto por sequências com alta conservação no nível de nucleotídeos, está presente no genoma de todas as gramíneas analisadas (híbridos e parentais da cana-de-acúcar, milho e arroz) com um baixo número de cópias, teve a sua expressão detectada em folhas, raízes e mais intensamente em calos cana. Além disso, apresenta alta similaridade de sequências com transposases domesticadas descritas na literatura. O grupo II, por sua vez, é composto por sequências mais heterogêneas, que apresentam similaridade com os transposons originais que constituem a superfamília hAT: hobo (de Drosophila melanogaster), Ac (de Zea mays) e Tam3 (de Antirrhinum majus). Sua distribuição é restrita ao genoma de Saccharum, com um número de cópias maior que o grupo I. Um ensaio de PCR-Inversa identificou terminações inversas repetidas (TIRs) para o cDNA TE221 do grupo II. A partir de iniciadores desenhados sobre estas TIRs foi possível recuperar dois elementos, de 3,5kb e 4,2kb, respectivamente, e um MITE de 250 pb, todos homólogos a hAT. Este resultado demonstrou que a estratégia utilizada para recuperar elementos do genoma da cana-de-açúcar a partir do cDNA TE221 mostrou-se eficiente. Homólogos aos grupos I e II de cana-de-acúcar foram identificados em bancos de dados de milho, arroz e arabidopsis. Estes dados sugerem que a separação dos dois grupos ocorreu antes da divergência entre as classes Monocotiledonea e Eudicotiledonea. Com base nos resultados aqui apresentados sugerimos que um transposon ancestral do tipo hAT, presente nas angiospermas anteriormente à separação de Monocotiledonea e Eudicotiledonea, teve sua transposase capturada na formação de um gene com função celular. A partir do evento da domesticação, estas transposases seguiram dois caminhos evolutivos distintos, um como gene funcional e outro como um transposon tradicional. Estas duas formas de transposase do tipo hAT podem ser encontradas no genoma da cana-de-acúcar, representadas pelos elementos dos grupos I e II, respectivamente. / Transposable elements (TEs) are mobile genetic sequences. Their mutagenic capacity makes them important sources of variation in the genomes. These elements have another important evolutionary role as donors of functional protein domains in the formation of new genes. 276 cDNA clones homologous to TEs were previously identified in the Brazilian Sugarcane Expressed Sequence Tag Project (SUCEST) databases. In this work, we have obtained the full sequences of 156 for these clones. These sequences were compared with Genbank database. We have identified 9 families of transposons and 11 families of retrotransposons. The most representative families found amongst the transposons were MuDr and hAT (wich encompass Ac and Tam3), with 43 and 32 cDNAs, respectively. Amongst the retrotransposons, the most representative family was Hopscotch, with 25 cDNAs. After this global analysis, we have focused our investigation in the hAT-like cDNAs. A comparative analysis of these cDNAs has revealed a profile of two distinct groups. Group I is composed of sequences with high conservation at nucleotide level, it is present in the genome of all grasses analysed (hybrids and parentals of sugarcane, maize and rice) with low copy number, it is expressed in leaves and roots of sugarcane, and more intensely in callus. In addition, group I sequences have clustered with domesticated transposases. The group II is composed of more heterogeneous sequences similar with the original elements that constitute the hAT superfamily: hobo (from Drosophilla melanogaster), Ac (from Zea mays) and Tam3 (from Antirrhinum majus). This group was shown to be restricted to the genome of Saccharum, with higher copy number than group one. Inverse-PCR assays has identified terminal inverted repeats (TIRs) to the cDNA TE221 from group II. Primers based on the sequences of the TIRs allowed us to recover three elements hAT-like from sugarcane’s genomic DNA: one of 3,5kb and another of 4,2kb, and a MITE of 250 bp. These results corroborate the strategy applied in order to recover elements from the sugarcane´s genome. Sequences homologous to both sugarcane group I and group II were found also in maize and rice, as well as in arabidopsis databases. These data suggest that the divergence of the two groups occured before the separation between the classes Monocotiledonea and Eudicotiledonea. Based on our results, we suggest the existence of an ancestral transposon hAT-like, present in angiosperms before the separation between Monocotiledonea and Eudicotiledonea, of which the transposase was captured to compose a new gene with some cellular function. Since the domestication event, these transposases followed distinct evolutive pathways, one as a regular gene and another as a bona fide transposon. These two forms of hAT-like transposases could be found in the sugarcane’s genome, represented by the elements from groups I and II, respectively.
13

An investigation into the learning experience of textile designers and makers : examining the relationship between experiential learning and 'intelligent making'

Toner-Edgar, Maggi January 2008 (has links)
This thesis examines the relationship between textile craft practice and Kolb's Theory of Experiential Learning. The nature of craft practice has been described as 'Intelligent Making'. The aims were to investigate the term 'Intelligent Making' and construct a framework of the learning experience, on which to base the critical context for future textile practice. A review was made of textile craft practice, investigating models of experiential and reflective learning theories. Experiential Learning Theory and 'Intelligent Making' in textile practice were found to be similar, although the main difference was in relation to reflective observation. The textile making process was examined at under-graduate, post graduate and practitioner levels with self-observation, through a reflective journal, based upon my own hat-making process. Reflexivity was used to explicate the embodied knowledge, made visible through materials and methods of making. This research demonstrates that an extended understanding is based on the fact that reflexivity is the methodological approach embedded within textile practice. The critical capacity of textiles was demonstrated through reflective observation, analysis and evaluation. Shared reflection describes the nature of the process and may enable each maker to restructure their own practice. One advantage of this research is the enhancement of a shared language for textile makers and an evolving reflexive textile vocabulary. This investigation results in a newly proposed visualisation of the making process creating an extended framework to previous models, to advance the future critical context of textile practice. Both volumes of this thesis are combined sequentially into the attached file.
14

Hubble PanCET: an isothermal day-side atmosphere for the bloated gas-giant HAT-P-32Ab

Nikolov, N., Sing, D. K., Goyal, J., Henry, G. W., Wakeford, H. R., Evans, T. M., López-Morales, M., García Muñoz, A., Ben-Jaffel, L., Sanz-Forcada, J., Ballester, G. E., Kataria, T., Barstow, J. K., Bourrier, V., Buchhave, L. A., Cohen, O., Deming, D., Ehrenreich, D., Knutson, H., Lavvas, P, Lecavelier des Etangs, A., Lewis, N. K., Mandell, A. M., Williamson, M. H. 02 1900 (has links)
We present a thermal emission spectrum of the bloated hot Jupiter HAT-P-32Ab from a single eclipse observation made in spatial scan mode with the Wide Field Camera 3 (WFC3) aboard the Hubble Space Telescope (HST). The spectrum covers the wavelength regime from 1.123 to 1.644 mu m which is binned into 14 eclipse depths measured to an averaged precision of 104 parts-per million. The spectrum is unaffected by a dilution from the close M-dwarf companion HAT-P-32B, which was fully resolved. We complemented our spectrum with literature results and performed a comparative forward and retrieval analysis with the 1D radiative-convective ATMO model. Assuming solar abundance of the planet atmosphere, we find that the measured spectrum can best be explained by the spectrum of a blackbody isothermal atmosphere with T-p = 1995 +/- 17 K, but can equally well be described by a spectrum with modest thermal inversion. The retrieved spectrum suggests emission from VO at the WFC3 wavelengths and no evidence of the 1.4 mu m water feature. The emission models with temperature profiles decreasing with height are rejected at a high confidence. An isothermal or inverted spectrum can imply a clear atmosphere with an absorber, a dusty cloud deck or a combination of both. We find that the planet can have continuum of values for the albedo and recirculation, ranging from high albedo and poor recirculation to low albedo and efficient recirculation. Optical spectroscopy of the planet's day-side or thermal emission phase curves can potentially resolve the current albedo with recirculation degeneracy.
15

Le photomarquage en fonction de la température du récepteur d'angiotensine II de type 1 mène à une meilleure compréhension du mécanisme d'activation

Arsenault, Jason January 2010 (has links)
Les récepteurs couplés aux protéines G (RCPG) sont réfractaires à l'application efficace des méthodes structurales pour étudier la structure 3D du complexe récepteur-ligands. Nous présentons une nouvelle méthode basée sur l'analyse de l'interaction ligand-RCPG à différentes températures avec le photomarquage par affinité exploitant des ligands contenant le photomarqueur pBenzoyl-L-phénylalanine (Bpa). Cette approche nous a permis de générer un modèle du complexe du récepteur d'angiotensine H de type 1 (hAT [indice inférieur 1] ) avec le [Sar [indice supérieur 1] , Bpa [indice supérieur 8] AngII à plus haute résolution et aussi d'identifier des différences conformationnelles entre la forme active et la forme inactive du récepteur. Notre laboratoire a démontré que la position 8 du [indice supérieur 125] I-[Sar [indice supérieur 1] , Bpa [indice supérieur 8] AngII formait un lien covalent avec le domaine transmembranaire 7 (DTM7) dans hAT [indice inférieur 1] . Le Bpa, qui a une sélectivité réactionnelle pour les méthionines (Met), était ambigue dans son rayon d'action variable. Néanmoins, cette sélectivité a permis d'élaborer l'essai de proximité aux Met (MPA). La température de photomarquage a été subséquemment identifiée comme un facteur important à contrôler dans les études de photomarquage. En étudiant ainsi les mutants Met positifs en MPA du récepteur hAT 1 , nous avons observé des changements importants lors de l'interaction ligand-récepteur en fonction de la température. A basse température, les fluctuations conformationnelles du complexe ligand-récepteur sont minimisées. Inversement, à 37 [degrés Celsius], le complexe démontre une flexibilité structurale très importante.Les analyses de ces résidus photomarqués suivis d'une digestion au CNBr'démontrent que l'accessibilité aux Met augmente proportionnellement avec la température. Ensuite, en photomarquant le mutant constitutivement actif, le N111G-hAT [indice inférieur 1] , nous pouvons comparer les différences entre une forme basale et une forme plus active du récepteur.Les résultats sont quantifiés en un ratio du marquage Met/DTMVII et ceci nous donne un indice d'accessibilité entre le ligand et le résidu muté dans hAT [indice inférieur 1] . Nous avons observé des différences thermodépendantes entre ces ratios d'accessibilités des mutants X[arrow right]Met et N111G/X[arrow right]Met. Ces ratios d'accessibilités ont été transformés en distance et insérés comme contraintes dans la modélisation moléculaire par refondu simulée. Nous voyons dans le récepteur un éloignement du haut du DTMVI, un rapprochement du DTMII et V et un petit déplacement du DTMIII lors de l'activation.Les différences dans les structures sont à la base des mécanismes d'activations d'hAT [indice inférieur 1] et des RCPGs en général.
16

HAT-P-67b: An Extremely Low Density Saturn Transiting an F-subgiant Confirmed via Doppler Tomography

Zhou, G., Bakos, G. Á., Hartman, J. D., Latham, D. W., Torres, G., Bhatti, W., Penev, K., Buchhave, L., Kovács, G., Bieryla, A., Quinn, S., Isaacson, H., Fulton, B. J., Falco, E., Csubry, Z., Everett, M., Szklenar, T., Esquerdo, G., Berlind, P., Calkins, M. L., Béky, B., Knox, R. P., Hinz, P., Horch, E. P., Hirsch, L., Howell, S. B., Noyes, R. W., Marcy, G., Val-Borro, M. de, Lázár, J., Papp, I., Sári, P. 13 April 2017 (has links)
We report the discovery of HAT-P-67b, which is a hot-Saturn transiting a rapidly rotating F-subgiant. HAT-P-67b has a radius of = R-p 2.085(-0.071)(+0.096) R-J, and orbites a M-* = 1.642(-0.072)(+0.155)M(circle dot) , R-* = 2.546(-0.084)(+0.099) R-circle dot host star in a similar to 4.81 day period orbit. We place an upper limit on the mass of the planet via radial velocity measurements to be M-p < 0.59 M-J , and a lower limit of >0.056 M-J by limitations on Roche lobe overflow. Despite being a subgiant, the host star still exhibits relatively rapid rotation, with a projected rotational velocity of vsin I-* = 35.8 +/- 1.1 km s(-1), which makes it difficult to precisely determine the mass of the planet using radial velocities. We validated HAT-P-67b via two Doppler tomographic detections of the planetary transit, which eliminate potential eclipsing binary blend scenarios. The Doppler tomographic observations also confirm that HAT-P-67b has an orbit that is aligned to within 12 degrees, in projection, with the spin of its host star. HAT-P-67b receives strong UV irradiation and is among one of the lowest density planets known, which makes it a good candidate for future UV transit observations in the search for an extended hydrogen exosphere.
17

Fliers from dry season

Glazer, Noa 01 January 2015 (has links)
In my studio practice I attempt to create sensual experiences from which nothing is learned and lack resolution; this thesis is an attempt to find ways to outline these experiences. However, this attempt will eventually lead to something entirely different, for these experiences are undefinable and impossible to investigate. I will try to show how the components of the work, rather than forming a direct link to a chain of thoughts or associations, summon an experience that is derived only from the encounter itself.
18

Recording Review of Old Hat Records

Olson, Ted 01 November 2012 (has links)
Review of Old Hat Records
19

Likheter blir olikheter : En komparation av Anne B. Ragdes Berlinerpopplarna och Alice Munros "Kärlek, vänskap, hat"

Svensson, Joakim January 2013 (has links)
Uppsatsen behandlar Anne B. Ragdes roman Berlinerpopplarna (2007) och Alice Munros novell ”Kärlek, vänskap, hat” (2009). Båda verken är skrivna i modern tid av kvinnliga författare och innehåller en rad liknande stildrag, bland annat intern fokalisation inifrån flera olika karaktärer. Mitt syfte har varit att se vad som skiljer två verk med liknande drag och därigenom påvisa hur de stilgrepp och val författaren gör påverkar slutresultatet. För att finna svaret har jag använt komparation och jämfört varje aspekt av böckerna noggrant. Bland annat har jag studerat hur intern fokalisation används, vad som gjorts genom person- och miljöskildringar och hur de hemligheter som har stor vikt i respektive bok har hanterats. Mitt resultat visar att två till synes liknande texter kan skilja sig kraftigt då man ser närmare på dem. Författarna har genom sina val av stildrag och hur de används skapat helt skilda historier även på de ställen där de använder liknande metoder. Det visar sig bland annat genom att intern fokalisation i Berlinerpopplarna används för att få nära kontakt med flera karaktärer medan det i ”Kärlek, vänskap, hat” används för att se en karaktärs äventyr ur flera synvinklar och därmed skapa ironi.
20

Från hyllat fittstim till hatade genuspirayor : en studie av DN:s framställning av feminister

Jöves, Helena, Lyche Sjöquist, Fiodora January 2012 (has links)
För en tid sedan var det status att vara en del av fittstimmet. Ordet tycktes andas styrka, självständighet och attityd. Även politiker passade på att surfa i vågorna av stimmets strömmar. Feminismen hade anhängare i både det offentliga och hos gemene man (eller kvinna) och det var inget ögonbrynshöjande ställningstagande. Under det senaste decenniet tycks ordet fått en ny laddning och feminismen är inte längre det enda valet i strävan mot jämställdhet. Fittstimmet är upplöst och kvar finns några tappra genuspirayor som vässar tänderna för strid mot ”jämställdisternas” hotfulla nät.   I denna studie undersöks Dagens Nyheters porträttering av feminister under två tolvmånadersperioder med nio års mellanrum. Den kvantitativa studien med kvalitativa inslag besvarar i vilka huvudsakliga sammanhang feminister syns, hur de framställs och vilka skillnader det finns mellan perioderna. Forskning och begreppsdefinitioner samt en gedigen historisk tillbakablick i ämnet presenteras.   Resultatet visar hur feminister representeras främst i kulturdebatten men betydligt mer frekvent och spritt under den senare perioden. Under den tidiga perioden förknippas feminister mer med kvinnokampens mål och feminismen som ideologi. Den senare perioden utmärks av diskussioner kring feministhat, högerextremism och exkludering av specifika grupper.   Studien visar även hur feminister gått från att porträtteras odramatiskt till att placeras i ett betydligt hårdare klimat med hot och påhopp. De trivialiseras, förminskas och anklagas för att vara ologiska och mot moderskapet. Samtidigt mobiliserar enskilda feminister hårda motangrepp och efterfrågar engagemang kring den fortsatta kvinnokampens mål och betydelse i det framtida samhället. Vi visar även hur feministerna ger tillbaka med liknande strategier som de själva genom tiderna blivit utsatta för.   Studien visar trots allt en viss positiv utveckling gentemot tidigare forskning, då vissa av de mest tydliga nidbilderna inte går att finna i DN.

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