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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.
101

Det känns som att barnen kan mer än vad vi kan ibland : Förskollärares uppfattningar om bildskapande som estetisk lärprocess och digitala verktyg i Lpfö18

Hasselgren, Melanie January 2019 (has links)
This thesis focus on the change in goal within the revised curriculum where digital techniques are included and the preschool teachers’ perception of pedagogical work with aesthetic learning processes. The study has a phenomenographic approach. Semi-structured interviews were conducted to collect data. The analysis points out differences and similarities in the preschool teacher’s perceptions of image creation. The result of the study show that the preschool teachers’ perceptions show similarities and differences in children´s free image creation and the controlled image creation initiated by the adults. The preschool teacher’s perceptions of the controlled image creation show that it is often used as an aesthetic learning process to learn another subject or to process an experience while the perceptions of free image creation are that it happens more often spontaneously. It is used in the different theme areas of the preschool, because they perceive themselves lacking in knowledge and/-or interest. The preschool teacher’s perceptions of digital tools in relation to the preschool’s revised curriculum are that it is seen as a complement to analogue tools, but that the environment believes that the digital will replace analogue tools. The preschool teachers perceive that they lack knowledge about digital tools and that makes it difficult to implement it in teaching so that it will become a natural part of the teaching. The conclusion is that the preschool teachers are perceived to have a basic knowledge in the field of image creation and the digital tools. In order for the image creation and the preschool’s revised curriculum to be implemented, preschool teachers need more knowledge. Through knowledge is interest born and with more interest and knowledge, more aesthetic learning processes are created. / Med utgångspunkt i hur förskollärare uppfattar hur förskolans reviderade läroplan med digitala tekniker och förändrad målbeskrivning så är syftet för studien att fördjupa förståelsen kring hur förskollärare uppfattar det pedagogiska arbetet med estetiska lärprocesser med fokus på bildskapande. Undersökningen genomfördes med en fenomenografisk metodansats och halvstrukturerade intervjuer. Analysen genomfördes för att synliggöra skillnader och likheter i förskollärarnas uppfattningar om bildskapandet. Resultatet visar att förskollärarnas uppfattningar om det fria bildskapandet är barninitierat och sker spontant. Detta ses som det” riktiga” bildskapandet och barnen skapar tillsammans med kompisar. Förskollärarnas uppfattningar om det styrda bildskapandet visar att det ofta används som estetisk lärprocess till att lära ett annat ämne eller för att bearbeta en upplevelse. Det används inom förskolans olika temaområden, detta för att de uppfattar sig själva sakna kunskap och/- eller intresse. Förskollärarnas uppfattningar om digitala verktyg i relation till förskolans reviderade läroplan är att det ses som ett komplement till analoga verktyg, men att omgivningen tror att det digitala ska ersätta analoga verktyg. Förskollärarna uppfattar att de saknar kunskaper kring digitala verktyg och det gör det svårt att implementera det i undervisningen så att det ska bli en naturlig del i undervisningen. Slutsatsen är att förskollärarna uppfattas ha en grundkunskap inom bildskapandet samt de digitala verktygen. För att bildskapandet och förskolans reviderade läroplan ska kunna genomföras så behöver förskollärarna få mer kunskap. Genom kunskap föds intresse och med mer intresse och kunskap skapas fler estetiska lärprocesser.
102

Interprétation et amélioration d’une procédure de démodulation itérative / Interpretation and amelioration of an iterative demodulation procedure

Naja, Ziad 01 April 2011 (has links)
La géométrie de l’information est la théorie mathématique qui applique les méthodes de la géométrie différentielle dans le domaine des statistiques et de la théorie de l’information. C’est une technique très prometteuse pour l’analyse et l’illustration des algorithmes itératifs utilisés en communications numériques. Cette thèse porte sur l’application de cette technique ainsi que d’autre technique d’optimisation bien connue, l’algorithme itératif du point proximal, sur les algorithmes itératifs en général. Nous avons ainsi trouvé des interprétations géométriques (basée sur la géométrie de l’information) et proximales (basée sur l’algorithme du point proximal)intéressantes dans le cas d’un algorithme itératif de calcul de la capacité des canaux discrets sans mémoire, l’algorithme de Blahut-Arimoto. L’idée étant d’étendre cette application sur une classe d’algorithmes itératifs plus complexes. Nous avons ainsi choisi d’analyser l’algorithme de décodage itératif des modulations codées à bits entrelacés afin de trouver quelques interprétations et essayer de proposer des liens existant avec le critère optimal de maximum de vraisemblance et d’autres algorithmes bien connus dans le but d’apporter certaines améliorations par rapport au cas classique de cet algorithme, en particulier l’étude de la convergence.Mots-clefs : Géométrie de l’information, algorithme du point proximal, algorithme de Blahut-Arimoto, décodage itératif, Modulations codées à bits entrelacés, maximum de vraisemblance. / Information geometry is a mathematical theory that applies methods of differential geometryin the fields of statistics and information theory. It is a very promising technique foranalyzing iterative algorithms used in digital communications. In this thesis, we apply this technique, in addition to the proximal point algorithm, to iterative algorithms. First, we have found some geometrical and proximal point interpretations in the case of an iterative algorithmfor computing the capacity of discrete and memoryless channel, the Blahut-Arimoto algorithm.Interesting results obtained motivated us to extend this application to a larger class of iterative algorithms. Then, we have studied in details iterative decoding algorithm of Bit Interleaved Coded Modulation (BICM) in order to analyse and propose some ameliorations of the classical decoding case. We propose a proximal point interpretation of this iterative process and find the link with some well known decoding algorithms, the Maximum likelihood decoding.
103

O papel de ATRAP (AT1R associated protein) na modulação de NHE3 mediada por angiotensina II. / ATRAP (AT1R associated protein) role on modulation of angiotensin II-mediated NHE3 activity.

Polidoro, Juliano Zequini 15 September 2014 (has links)
Os experimentos indicam, como já demonstrado em estudos prévios do laboratório, que angiotensina II (Ang II) apresenta efeito estimulatório sobre a cinética de recuperação de pHi em células OKP. Tal estímulo não é acentuado pela super-expressão de AT1aR recombinante, ao contrário do que imaginávamos inicialmente. Acreditamos que, por conta da capacidade de amplificação de sinal característica dos receptores acoplados a proteína G, um aumento de expressão do receptor AT1aR em relação ao nível endógeno seja redundante para o fenômeno biológico estudado. Por outro lado, os resultados para o grupo com super-expressão de ATRAP corroboram nossa hipótese inicial, ao indicar uma atenuação do efeito de Ang II sobre a recuperação de pHi, em comparação aos demais grupos experimentais tratados com Ang II. Considerando que a recuperação de pHi em células OKP reflete essencialmente a atividade de troca Na+/H+ mediada pelo contra-transportador NHE3, podemos concluir que a regulação positiva de NHE3 via AT1aR/AngII é prejudicada pelo aumento de expressão da proteína ATRAP. / The experimental data suggests that, as shown in previous works from our laboratory, angiotensin II (Ang II) raises the pHi recovery rate in OKP cells. This upregulation is not enhanced by recombinant AT1aR overexpression, contrary to our initial hypothesis. We believe that, due to signal amplification mediated by G-protein coupled receptors, any increase in AT1aR would be redundant considering the biological phenomenon of interest. On the other hand, results from the ATRAP overexpression group supports our initial hypothesis, pointing an attenuated effect of Ang II over pHi recovery in relation to the remaining groups treated with Ang II. Considering that pHi recovery in OKP cells primarily reflects the Na+/H+ exchange activity mediated by NHE3 antiporter, we can conclude that NHE3 upregulation mediated by AT1aR/AngII is impaired by an increase in ATRAP protein expression.
104

Avaliação de marcadores de lesão do túbulo proximal renal e incidência de redução da filtração glomerular em pacientes portadores de Hepatite B em uso de tenofovir / Evaluation of markers of renal proximal tubule injury and incidence of reduced glomerular filtration in patients with hepatitis B using tenofovir

Laurindo, Álan Fernandes 27 January 2015 (has links)
Tenofovir (TDF), um antirretroviral análogo nucleotídeo inibidor da transcriptase reversa, indicado para o tratamento da infecção pelo vírus da Hepatite B em indivíduos HBeAg reagentes, não cirróticos, tem sido implicado na ocorrência de Injúria renal aguda (IRA) e lesão do túbulo proximal renal (TPR), com características semelhantes à Síndrome de Fanconi, caracterizada por glicosúria, bicarbonatúria, fosfatúria, uricosúria e proteinúria de baixo peso molecular. Outros trabalhos sugerem que os pacientes em uso de TDF sofram toxicidade aos glomérulos, com uma pequena, porém significante redução da taxa de filtração glomerular. O tempo de uso da droga para que ocorra lesão renal é desconhecido. Entretanto, a maioria dos estudos de investigação de nefrotoxicidade do TDF foi realizada em pacientes portadores de infecção pelo HIV. Especula-se que a nefrotoxicidade desta droga possa ser exacerbada ou reduzida pelo uso de outras medicações, frequentemente usadas por pacientes com HIV, que competem com o transporte tubular ou com sua metabolização, aumentando o seu nível sérico. O objetivo geral deste trabalho é avaliar prospectivamente a incidência de lesão renal pelo uso de TDF em pacientes portadores de hepatite B. Os objetivos específicos deste trabalho são: (1) avaliar incidência de lesão do TPR através da avaliação da excreção urinária de ácido úrico, fósforo e da proteína de baixo peso molecular neutrophil gelatinase associated lipocalin (NGAL); (2) avaliar a incidência de redução aguda da taxa de filtração glomerular (LRA) ou redução crônica da mesma. Métodos: Foram incluídos 24 pacientes portadores de Hepatite B que tiveram indicação de iniciar o uso de TDF com idade superior a 18 anos ou inferior a 75 anos. Neste estudo prospectivo, foi realizado a coleta de dados clínicos (idade, gênero, etnia, tempo de doença, antecedentes pessoais, medicações concomitantes, fator de risco para contaminação do VHB, história familiar de infecção VHB) e a avaliação laboratorial foi feita através da coleta de sangue e urina feitas antes do início do uso do TDF e, posteriormente à sua introdução, semestralmente durante 2 anos. Ao final do seguimento foi avaliada a incidência de lesão renal pelo uso de TDF, através das seguintes dosagens: glicemia, fosfatemia, gasometria, creatinina e Cistatina C séricas, microalbuminúria, proteinúria, proteinúria de baixo peso molecular (NGAL), clearance de creatinina, fosfatúria, uricosúria e urina rotina. Foi feita análise estatística comparativa entre os pacientes que usaram o TDF pré tratamento e pós tratamento para detectar lesão do TPR ou redução da taxa de filtração glomerular ao longo do tempo. Resultados: Não foi identificado aumento significativo da creatinina no decorrer do estudo (p = 0,09; R = 2,4%), entretanto, foi observada uma queda significativa nos valores do clearance de creatinina em 24 horas (p < 0,01; R = 15,8%). Não foi observada tendência de queda da filtração glomerular através das fórmulas MDRD simplificada (p = 0,11), CKD-EPI (p=0,14), CKD-EPI cystatin C (p = 0,23). Em relação à cistatina C sérica também não foi observada sua elevação no decorrer do tempo (p=0,15; R = 2,4%). Não foi observado, utilizando-se modelo de regressão linear, aumento na excreção urinária de albumina no decorrer do estudo (p = 0,97; R = 0,00%), mas houve aumento significativo na proteinúria de 24h (p < 0,01). Foi observada também, redução da uricosúria com o passar do tempo (p = 0,01; R = 6,7%) e houve correlação positiva entre o clearance de creatinina dosado em urina de 24 horas e a excreção de ácido úrico em urina de 24 horas (p=0,01; r = + 0,60). A fração de excreção de fósforo (urina de 24h): não foi observada alteração no decorrer do tempo (p = 0,83; R = 0,5%), porém houve correlação negativa com entre o clearance de creatinina dosado em urina de 24 horas e a fração de excreção de fósforo (FePO4) dosada em urina de 24 horas (p = 0,05; r = - 0,25). A detecção de NGAL na urina foi feita pelo índice UNGAL/Ucreat e não foi observado aumento significativo de sua excreção no decorrer do tempo (p = 0,40, r = 0,8%). Conclusão: em conclusão no presente estudo observou-se desenvolvimento de lesão renal aguda em 10% dos pacientes em uso de tenofovir e redução significativa da filtração glomerular. A fosfatúria e proteinúria observados sugerem que a lesão tenha sido decorrente de tubulopatia proximal e os marcadores mais específicos de lesão renal, cistatina C e NGAL, não foram superiores aos biomarcadores disponíveis na prática clínica na detecção destas alterações. / Tenofovir (TDF) a nucleotide analog reverse transcriptase inhibitor antiretroviral indicated for the treatment of infection with the hepatitis B virus in reagents HBeAg individuals, non-cirrhotic patients, has been implicated in the occurrence of acute kidney Injury (AKI) and the proximal tubule injury kidney (TPR), with similar to Fanconi syndrome characterized by glucosuria, bicarbonatúria, phosphaturia, proteinuria, uricosuria and low molecular weight characteristics. Other studies suggest that patients using TDF toxicity suffer the glomeruli, with a small but significant reduction in glomerular filtration rate. The time of drug use for kidney damage that occurs is unknown. However, most of the research studies of nephrotoxicity TDF was performed in patients with HIV infection. It is speculated that the nephrotoxicity of this drug may be exacerbated or reduced by the use of other medications, often used by patients with HIV, which compete with the tubular transport or metabolism, increasing its serum level. The overall objective of this study is to prospectively evaluate the incidence of renal injury by the use of TDF in patients with hepatitis B. The specific objectives of this work are: (1) assess the incidence of injury TPR by assessment of urinary excretion of uric acid, phosphorus and protein of low molecular weight neutrophil gelatinase associated lipocalin (NGAL); (2) assess the incidence of acute reduction in glomerular filtration rate (IRA) or chronic reduction. Methods: 24 patients with hepatitis B who were advised to initiate the use of TDF over the age of 18 years or below 75 years were included. In this prospective study, the collection of clinical data (age, gender, ethnicity, duration of disease, personal history, concomitant medications, risk factor for HBV infection, family history of HBV infection) and laboratory evaluation was done by collect blood and urine samples taken before initiation of the use of TDF and after its introduction, semiannually for 2 years. At final follow-up the incidence of renal injury by the use of TDF was assessed through the following dosages: glucose, phosphatemia, gases, creatinine and serum cystatin C, microalbuminuria, proteinuria, low molecular weight proteinuria (NGAL), clearance creatinine, phosphaturia, uricosuria and urine routine. The comparative statistical analysis of patients using TDF pre-treatment and post treatment to detect the TPR injury or reduced glomerular filtration rate over time. Results: There was not significant increase in creatinine identified during the study (p = 0.09; R = 2.4%), however, a significant decrease was observed in the values of creatinine clearance at 24 hours (p <0.01; R = 15.8%). No downward trend was observed in glomerular filtration through the simplified MDRD formulas (p = 0.11), CKD-EPI (p = 0.14), CKD-EPI cystatin C (p = 0.23). Regarding the serum cystatin C its elevation was not observed over time (p = 0.15, R = 2.4%). Increased urinary albumin excretion during the study was not observed using a linear regression model (p = 0.97, R = 0.00%), but there was significant increase in 24-hour proteinuria (p <0, 01). And there was a positive correlation between creatinine clearance at 24 hour urine and the excretion of uric acid in 24 hour urine (p = 0.01, R = + 0.60), uricosuria reduction over time was also observed (p = 0.01, R = 6.7%). No change was observed over time in the fractional excretion of phosphorus (24 h urine), (p = 0.83; R = 0.5%), but there was a negative correlation between creatinine clearance urine dosed at 24 hours and fractional excretion of phosphorus (FePO4) measured in 24 hour urine (p = 0.05, r = - 0.25). The detection of NGAL in the urine was taken by UNGAL / Ucreat index and was not observed significant increase in excretion over time (p = 0.40, r = 0.8%). Conclusion: In conclusion at the present study we observed the development of acute kidney injury in 10% of patients using tenofovir and a significant reduction in glomerular filtration. The phosphaturia and proteinuria observed suggest that the injury has been caused by proximal tubulopathy and more specific markers of renal injury as cystatin C and NGAL were not greater than the available biomarkers in clinical practice for their detection.
105

Método de ponto proximal para problemas de equilíbrio em espaços de Hilbert

Viana, Daiana dos Santos 23 September 2013 (has links)
Made available in DSpace on 2015-04-22T22:16:06Z (GMT). No. of bitstreams: 1 daiana santos.pdf: 1011976 bytes, checksum: 0d1f23d4c01774fbad224c1c0fbe0359 (MD5) Previous issue date: 2013-09-23 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / In this dissertation, we present a proximal point method for solving problems balance in Hilbert spaces proposed by Alfredo Iusem and Wilfredo Sosa in [1]. We analyzed the convergence of this mehtod for troubleshooting balance. We verified the sequence generated by the method of classical proximal point and generated sequence the proximal point method to balance problems are the same. These results were obtained using variations of monotonicity of the function that defines the balance problem. In the final analysis is made on the weakening of the hypothesis assumed by function. / Nesta dissertação, apresentamos um método de ponto proximal para resolução de problemas de equilíbrio em espaços de Hilbert proposto por Alfredo Iusem e Wilfredo Sosa em [1]. Analisamos a convergência deste método para soluções de problemas de equilíbrio. Verificamos que a sequência gerada pelo método de ponto proximal clássico e a sequência gerada pelo método de ponto proximal para problemas de equilíbrio coincidem. Esses resultados foram obtidos usando variações de monotonicidade sobre a função que define o problema de equilíbrio. Uma análise final é feita sobre o enfraquecimento das hipóteses assumidas pela função.
106

Ação do ANP no efeito não genômico da aldosterona sobre o trocador Na+/H+ no segmento S3 do túbulo proximal de rato - Estudos em túbulos isolados: função do cálcio citosólico. / Action of ANP on the nongenomic effects of aldosterone on the Na+/H+ exchanger in the S3 segment of proximal tubule of rat: studies in isolated tubules role of cytosolic calcium.

Braga Sobrinho, Celso 16 December 2008 (has links)
O objetivo do presente trabalho foi analisar o papel do ANP na ação não genômica da Aldosterona sobre o trocador Na+/H+ no segmento S3 do túbulo proximal de rato, isolado, in vitro. Os resultados indicam que o pHi basal do segmento S3 proximal de ratos é 7.20 + ou - 0.009 (n = 47/209). O valor médio da velocidade de extrusão celular de H+ na condição controle é de 0.195 + ou - 0.012 pHi/min (n = 16/96). Os dados confirmam que a aldosterona apresenta um efeito bifásico sobre o NHE1: em baixas doses (10-12 M) o estimula, enquanto que em altas doses (10-6M), o inibe. O ANP (10-6 M) não possui efeito sobre o NHE1; contudo, o ANP previne ambos os efeitos da aldosterona sobre esse trocador. O valor médio da concentração do cálcio no citosol ([Ca2+]i) na condição controle é 100 ± 1 (n = 5) hM Adicionalmente, nossos estudos mostram que o ANP diminui a [Ca2+]i e inibe o efeito estimulatório de ambas as doses de aldosterona sobre esse parâmetro. / The effects of aldosterone and ANP(2 min preincubation) on the intracellular pH recovery rate (pHirr) after the acid load induced by NH4Cl and on the [Ca2+]i were investigated in isolated rat S3 segment. The basal pHi was 7.20 + ou - 0.009(n=47/209) and the basal pHirr via the Na+/H+ exchanger was 0.195 + ou - 0.012 pHi/min(n=16/96). Aldosterone(10-12M) caused an increase in the pHirr, but aldosterone(10-6M) decreased it. ANP(10-6M) alone or plus aldosterone(10-12 or 10-6 M) had no effect on pHirr. The basal [Ca2+]i was 100 + ou - 1(n=5)hM. After 1 min of Aldosterone pi there was a transient and dose-dependent increase of the [Ca2+]i and after 6 min pi there was a new increase of [Ca2+]i. ANP alone decreased the [Ca2+]i and prevented the stimulatory effects of aldosterone(10-12 or 10-6M) on this parameter. The data indicate a nongenomic action of aldosterone and ANP on the Na+/H+ exchanger and on [Ca2+]i and are compatible with stimulation of the this exchanger by increases in [Ca2+]i in the lower range (at10-12M aldosterone) and inhibition by increases at high levels (at10-6M aldosterone).
107

Efeitos não-genômicos dos hormônios esteróides - aldosterona e corticosterona - sobre a acidificação do túbulo proximal (S2) de ratos: estudos de microperfusão tubular e capilar, in vivo . / Nongenomic effect of steroid hormones - aldosterone and corticosterone - on acidification of rat proximal tubule (S2) studies by tubular and capillary microperfusion, in vivo .

Pergher, Patrícia e Silva 02 September 2010 (has links)
O objetivo foi determinar se aldosterona e corticosterona agem sobre a acidificação do túbulo proximal e se esses efeitos são genômicos e/ou não-genômicos. A reabsorção de HCO3- foi avaliada por microperfusão estacionária. Aldosterona e corticosterona perfundidas na luz tubular causaram aumento significante do JHCO3-. Na presença de etanol, actinomicina D, cicloheximida ou espironolactona, o JHCO3- foi estatisticamente igual ao valor controle (2,84 ± 0,079 nmol.cm-2.s-1). RU486 sozinho inibiu o efeito estimulador da aldosterona e corticosterona. Losartan não alterou o JHCO3-. Concanomicina ou S3226 diminuiram o efeito estimulador da corticosterona. A aldosterona perfundida nos capilares peritubulares aumentou o JHCO3-. Assim, a aldosterona e corticosterona tem um efeito rápido, não-genômico, estimulante do JHCO3-, provavelmente com a participação do GR e pela ativação do NH3 e da H+-ATPase luminais. Além disto, a aldosterona e corticosterona endógenas estimulam o JHCO3- no túbulo proximal. / The purpose was to determine if aldosterone and corticosterone act on the acidification of proximal tubule and if these hormonal effects are genomic and/or nongenomic. Bicarbonate reabsorption was evaluated by microperfusion. Aldosterone and corticosterone caused a significant increase in JHCO3-. In the presence of ethanol, actinomycin D, cycloheximide or espironolactone, the JHCO3- was not different from the control value (2.84 ± 0.079 nmol.cm-2.s-1). However, in the presence of RU486 a decrease on JHCO3- was observed. Losartan inhibited the JHCO3-. Concanamicyn or S3226 decreased the stimulatory effect of corticosterone. Aldosterone perfused into peritubular capillaries also increased JHCO3-. Our results indicate that: aldosterone and corticosterone has a rapid, nongenomic, stimulatory effect on JHCO3-; probably, GR participates in this process and; this effect, probably, occurs by activation of luminal NH3 and H+-ATPase. Besides, endogenous aldosterone and corticosterone stimulate JHCO3-.
108

Etude de la localisation à grande échelle de la machinerie de transcription de classe III, et de sa relation avec le facteur de transcription TFIIS dans les cellules souches embryonnaires de souris / Genomic binding of Pol III transcription machinery and relationship with TFIIS transcription factor distribution in mouse embryonic stem cells

Carriere, Lucie 29 September 2011 (has links)
Chez les eucaryotes, l’ARN polymérase (RNAP) III transcrit les ARN de transferts, l’ARN ribosomique 5S, et plusieurs douzaines d’autres ARNs non traduits. Le génome des mammifères contient plusieurs milliers d’éléments répétés, les SINEs. In vitro, leur transcription dépend de la RNAP III. Le taux de transcription de la RNAP III détermine la croissance et la prolifération cellulaires, sa dérégulation a été associée à de nombreux cancers. Afin de caractériser la distribution sur l’ensemble du génome de la RNAP III et de ses facteurs de transcription TFIIIB et TFIIIC, nous avons développé un protocole très spécifique de ChIP-seq en tandem. Nous avons déterminé l’ensemble des gènes liés par la RNAP III dans les cellules souches embryonnaires de souris. Cet ensemble est bien inférieur au nombre de gènes prédits dans le génome. Nous avons également observé la RNAP III et ses facteurs de transcription liés à 30 régions non annotées, seule une d’entre elles est conservée chez l’humain. Un très faible nombre de SINEs sur un demi-million prédits est associé à la RNAP III. Notre étude révèle de nombreux sites liés uniquement par TFIIIC, nommés « extra-TFIIIC loci », ETC chez la levure. Ces sites sont associés à la protéine CTCF, et à la cohésine. La cohésine occupe les sites liés par CTCF, et contribue à la formation de boucles ADN, associées à la répression ou à l’activation de l’expression des gènes. Ces données suggèrent que TFIIIC peut jouer un rôle dans l’organisation de l’architecture chromosomique chez les souris. Nous avons également démontré que TCEA1, l’isoforme ubiquitaire de TFIIS, le facteur d’élongation de la RNAP II, est associée aux gènes actifs de classe III. Ceci suggére que TFIIS est un facteur de transcription de classe III. Finalement, la distribution de TFIIS aux gènes de classe II indique que le recrutement de TFIIS n’est pas suffisant pour contrôler la transition de la RNAP II pausée en 5’ des gènes en élongation. / In eukaryotes, RNA polymerase (RNAP) III transcribes the tRNAs, the 5S ribosomal RNA and a half a dozen known untranslated RNA. Mammalian genome contains several thousand of repeated elements, the Short interspersed repetitive elements (SINE). In vitro, they are transcribed by RNAP III. RNAP III transcription levels determine cell growth and proliferation and, importantly, its deregulation is associated with cancer. Looking at the genome-wide distribution of RNAP III and its transcription factors, TFIIIB and TFIIIC, we develop a highly specific tandem ChIP-sequencing method. We have determined the set of genes that are transcribed by RNAP III in mouse embryonic stem cells. We discovered that not all known class III genes were transcribed in ES cells. We also observed that RNAP III and its transcription factors were present at thirty unannotated sites on the mouse genome, only one of which was conserved in human. Only a couple of hundreds of SINEs out of more than half a million are associated with RNAP III in mouse ES cells. Our study reveals numerous ‘TFIIIC-only’ sites, called ETC for extra-TFIIIC loci in yeast. These sites are correlated with association of CTCF and the cohesin. Cohesin has been shown to occupy sites bound by CTCF and to contribute to DNA loop formation associated with gene repression or activation. This observation suggests that TFIIIC may play a role in chromosome organization in mouse. We also demonstrated that TCEA1, the ubiquitous isoform of TFIIS RNAP II elongation factor, is associated with active class III genes suggesting that TFIIS is a RNAP III transcription factor in mammals. Finally, the distribution of TFIIS on RNAP II-transcribed genes indicated that its recruitment does not control the transition of RNAP II paused at genes 5’ end into elongation.
109

"En dum fråga får ett dumt svar...klart man tänker sig för innan man frågar" : Ett elevperspektiv av sambandet mellan formativ bedömning och lärande i ett yrkessammanhang / "A stupid question get a stupid answer...of course you think before you ask" : A student perspective of the relationship between formative assesment and learning in a professional context

Knutsson, Sabina January 2012 (has links)
I studien undersöks sambandet mellan elevers upplevelser av lärarnas formativa bedömningar och effekten av lärandet i ett yrkessammanhang. Tidigare forskning visar att kommunikation kring lärandet är viktigt för att en vidare utveckling ska ske. Framförallt måste de kunskaper som saknas i förhållande till målen definieras av både lärare och elever, samt att målens kvalité är tydlig för båda parter. Avsikten är att öka förståelsen av hur yrkeslärare kan ge eleverna ett yrkeskunnande i linje med nationella målbeskrivningar via sin formativa bedömning. Undersökningen är gjord med kvalitativa forskningsintervjuer i en yrkesförberedande utbildning på två Hotell- och restaurangprogram. Den sociokulturella teorin om lärandet och den proximala utvecklingszonen har använts för att analysera resultatet. Resultatet visar att eleverna upplever att lärarna värderar specifika yrkeskvalitéer som speglar den yrkeskulturella förståelsen högst i samband med bedömningen. Dessa är enligt eleverna handlingskraft, arbetstempo, samarbetsförmåga, självständighet och att kunna prestera ett gott resultat. Lärandet i yrkessammanhanget saknar formativa bedömningar i den mening att lärarna inte kommunicerar kursmålen eller ger återkoppling på elevernas prestationer och utveckling. Lärarna förmedlar att yrkeskvalitéer bedöms genom kroppsspråk, kritisk återkoppling och det krav som ställs på eleverna att arbeta utan handledning. Resultatet visar också att eleverna redaninnanlärandetillfället måste ha ett tekniskt kunnande för att nå upp till lärarnas krav på yrkeskvalitéer. Yrkessammanhanget utgör en problematik kring det individuella lärandet eftersom undervisningen inte utgår från den enskilde elevens förutsättningar och behov. Vidare diskuteras den motsättning som utgör en yrkeslärares profession, att kunna förena kursmål och programmål med den egna synen på relevant kunskap inom ett yrkesområde, samt hur detta ska förmedlas och läras ut till eleverna.
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Samma lekvärld - olika språk : En liten studie om icke-verbal kommunikation i lek bland nyanlända barn i förskolan / Same world of play - different languages : A small study about non verbal communication in the play between newly arrived children in preeschool

Eriksson, Maria January 2015 (has links)
Syftet med denna studie är att undersöka nyanlända barns användande av icke-verbal kommunikation när de leker fritt, samt om det är någon skillnad när en pedagog är närvarande. Det studeras också i vilka karaktäristiska lekar de nyanlända barnen använder sin icke-verbala kommunikation mest. Studien är kvalitativ och undersökningen är utförd genom observationer, som utfördes under två dagars tid. Observationerna har utförts på en mångkulturell förskola där fokus har varit på fri lek, den proximala utvecklingszonen, pedagogiska atmosfärer och icke-verbal kommunikation. Resultaten visar att de nyanlända barnen använder sig av icke-verbala kommunikationsformer när de leker med varandra, detta tydliggörs i fyra karaktäristiska lekar som beskrivs i resultatdelen. Vidare framgår det av studien att det finns skillnader i barnens kommunikationsstrategier när det finns pedagogiskt stöd i leken gentemot när barnen leker utan pedagogers stöd. / The purpose of this study is to examine the newly arrived children's use of non -verbal communication when they are playing freely, and if there is any difference when a preschool teacher is present. It is also being studied in which characteristic games the newly arrived children use their non - verbal communication the most. The study is qualitative and the study is performed through observations. The observations have been conducted in a multicultural preschool where the focus has been at free play, the proximal development zone, educational atmospheres and non-verbal communication . The results show that the newly arrived children use non-verbal forms of communication when playing with each other , this is made clear in the four characteristic games described in the results section of this study. Furthermore , it appears from the study that there are differences in the children's communication strategies when there are educational support in children’s play compared to when they play and do not have educator’s support.

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