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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

Att inkludera flerspråkiga elever i muntliga aktiviteter : En intervjustudie med lärare i årskurs 6 / Including multilingual students in oral activities : An interview study with teachers in grade 6

Mustafai, Samira, Ayache, Manall, Salaei, Lana January 2021 (has links)
Syftet med studien är att undersöka sex mellanstadielärares uppfattningar om hur de inkluderar flerspråkiga elever i muntliga aktiviteter i svenskämnet i årskurs 6. Studien utgår från det sociokulturella perspektivet där begreppen IRF-sekvens och stöttning är centrala för arbetet. För att samla in data har semistrukturerade intervjuer med sex mellanstadielärare genomförts, som sedan bearbetas med hjälp av en innehållsanalys. De teman som framkom i innehållsanalysen var EPA-modellen, öva på uttal,  svårigheter som uppstår i undervisningen, trygghet i klassrummet samt arbetsmaterial och resurser. Av resultatet framgår det att samtliga lärare använder sig av olika undervisningsmetoder för att inkludera flerspråkiga elever i muntliga aktiviteter. Resultatet visade även att lärarna arbetar på olika sätt för att kunna variera undervisningen. Genom att lägga upp en plan inför lektionstillfället kan de planera vilken typ av stöttning som behövs gällande de flerspråkiga eleverna som befinner sig i olika utvecklingsstadier. Studiens resultat pekar på att svenskundervisningen bör anpassas efter flerspråkiga elevers förutsättningar och behov för att främja deras muntliga förmåga. Undervisningen ska präglas av variation för att eleverna ska kunna inkluderas och stöttas i muntliga aktiviteter.
22

Proteolysis of MDA5 and IPS-1 is not required for inhibition of the type I IFN response by poliovirus

Kotla, Swathi, Gustin, Kurt E. January 2015 (has links)
BACKGROUND: The type I interferon (IFN) response is a critical component of the innate immune response to infection by RNA viruses and is initiated via recognition of viral nucleic acids by RIG-like receptors (RLR). Engagement of these receptors in the cytoplasm initiates a signal transduction pathway leading to activation of the transcription factors NF-κB, ATF-2 and IRF-3 that coordinately upregulate transcription of type I IFN genes, such as that encoding IFN-β. In this study the impact of poliovirus infection on the type I interferon response has been examined. METHODS: The type I IFN response was assessed by measuring IFN-β mRNA levels using qRT-PCR and normalizing to levels of β-actin mRNA. The status of host factors involved in activation of the type I IFN response was examined by immunoblot, immunofluorescence microcopy and qRT-PCR. RESULTS: The results show that poliovirus infection results in induction of very low levels of IFN-β mRNA despite clear activation of NF-κB and ATF-2. In contrast, analysis of IRF-3 revealed no transcriptional induction of an IRF-3-responsive promoter or homodimerization of IRF-3 indicating it is not activated in poliovirus-infected cells. Exposure of poliovirus-infected cells to poly(I:C) results in lower levels of IFN-β mRNA synthesis and IRF-3 activation compared to mock-infected cells. Analysis of MDA-5 and IPS-1 revealed that these components of the RLR pathway were largely intact at times when the type I IFN response was suppressed. CONCLUSIONS: Collectively, these results demonstrate that poliovirus infection actively suppresses the host type I interferon response by blocking activation of IRF-3 and suggests that this is not mediated by cleavage of MDA-5 or IPS-1.
23

Epigenetic Regulation of Gene Transcription in Hematopoietic Tumors

Tshuikina Wiklander, Marina January 2008 (has links)
<p>Epigenetic modifications were shown to play an essential role in tumorigenesis. Epigenetic mechanisms can alter transcription in several ways, through DNA methylation and/or through histone modification. DNA methylation at the TSS (transcriptional start site) has been implicated in tumor development and gene silencing. However, several examples of atypical methylation were shown. In Paper I we present the ICSBP/IRF8 gene that belongs to the IRF family and has characteristics of a tumor suppressor gene. The ICSBP/IRF8 is fully methylated in the promoter and TSS regions in U-937 and despite high expression of the gene. Presence of positive histone marks suggests that methylated DNA can be overridden by histone modification.</p><p>In Paper II a panel of 13 MM (multiple myeloma) cell lines and 9 primary patient tumors were analysed for methylation status of the ICSBP/IRF8 gene. In most cell lines (8/13) the gene was partially or fully methylated and partial methylation was also observed in 1/9 primary tumors. In vitro methylation analysis and treatment with 5-aza-2’deoxycytidine (DAC) proved that the ICSBP/IRF8 gene is silenced by methylation and may be associated with the malignant phenotype.</p><p>In Paper III and IV the NFκB signalling pathway was analysed and the role of ATRA and TNFα induction. In Paper III the data shows that activation of the NFκB pathway is essential in ATRA-induced terminal differentiation in the U-937 cell line and IκBα (S32A/S36A) inhibits ATRA-induced differentiation and G1 cell cycle arrest. This was accompanied by delayed down-regulation of several cyclins (A and E) and up-regulation of p21<sup>WAF1/CIP1</sup> (CDKN1A) and p27<sup>KIP1</sup> (CDKN1B).</p><p>TNFα alone did not induce expression of RA-induced genes analysed in Paper IV. However, ATRA in combination with TNFα showed enhanced activation of RA-induced genes. TNFα triggers demethylation of H3K9me3/H3K9me2 and H3K4me3 at RAR/RXR target genes, which were not accompanied by changes in the level of H3K9-ac. This decrease in H3 methylation by TNFα may pave way for the later ATRA-induced gene transcription.</p>
24

Étude des mécanismes moléculaires impliqués dans la régulation de l'activité transriptionnelle d'IRF-3, de son activation à sa dégradation

Tremblay, Louis-Dominic January 2005 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
25

Protein:protein interaction between Interferon Regulatory Factor (IRF-1) and necleophosmin (NPM1)

Neelagandan, Kalainanghi S. January 2016 (has links)
Interferon Regulatory Factor -1 (IRF-1) is a transcription factor that acts as a tumour suppressor in cancer cells. The inactivation or deletion of IRF-1 either in one or both allele has been frequently reported in leukaemia and myelodysplasia (MDS). On the other hand nucleophosmin (NPM), a nucleo-cytoplasmic shuttling phosphoprotein is also known to be aberrant in some form of leukaemia. NPM was first proposed as a binding partner of IRF-1 in 1997 and suggested to inactivate IRF-1 by inhibiting its DNA binding ability. No further researches on the interaction between IRF-1 and NPM1 was reported prior to the start of my PhD. In the research presented here the interaction and mechanism by which IRF-1 might be inactivated by NPM was studied. Under the context of both NPM and IRF-1 being frequently associated with leukaemia and MDS, the study was done to determine the role of NPM under its naïve condition and a most frequent mutated condition (NPMc+), where the C-terminal of NPM was frequently mutated to give rise to a cytoplasmic NPM in certain leukaemia. In this current research, the direct interaction between IRF1 and NPM was further confirmed both in vitro as well as within the cells. Following this, the effect of this interaction in respect to the leukaemic condition having NPMc+ mutation was done, by comparing the end results on AML2 (leukaemic cells with intact wild type NPM) and AML3 (leukaemic cells having a single NPM allele mutated to form NPMc+) cells. In this research, overexpression of wild type NPM (NPMwt) was found to increase IRF-1 transcriptional activity. On further analysis, the DNA binding activity of IRF-1 due to the presence of NPMwt or NPMc+ was not always inhibited, instead it shows a change in binding specificity, where NPMwt bound IRF-1, lacks DNA binding ability and DNA bound IRF-1 has a reduced binding towards NPM. This is being studied further in terms of NPM overexpression and increased IRF-1 transcriptional activity, as the order of addition (order of interaction in vivo) plays a major role in activating or deactivating IRF-1. This along with the increased transcriptional activity of IRF-1 suggests a novel function of NPM, where it could act in favour of IRF- 1 activity. Additionally, the NPM induced change in IRF-1 localisation was confirmed by the cytoplasmic localised IRF-1 in NPMc+ expressing cells and nucleolar sequestration in NPMwt overexpressing cells. This gives a novel mechanism by which NPM regulates IRF-1. Further, the NPMc+ specific colocalisation of IRF-1 urges to study the other proteins that may have been re-localised in AML cells due to the NPMc+ specific interaction. A mass spectrometric analysis on the cellular distribution of total proteins were analysed between AML2 (cells with NPMwt) and AML3 (cells containing NPMc+). Specific proteins related to cancer have been identified to be differentially distributed rather than being a random translocation. With this being said, a peptide phage display technology coupled with next generation sequencing was done to identify NPMwt binding peptides that can be used in drug discovery process or as small molecule inhibitors or activators. Three different peptides were selected at the end of the study that bind very effectively to NPMwt. These peptide can either aid or restrict NPM activity and need to be validated and studied in the future.
26

Epigenetic Regulation of Gene Transcription in Hematopoietic Tumors

Tshuikina Wiklander, Marina January 2008 (has links)
Epigenetic modifications were shown to play an essential role in tumorigenesis. Epigenetic mechanisms can alter transcription in several ways, through DNA methylation and/or through histone modification. DNA methylation at the TSS (transcriptional start site) has been implicated in tumor development and gene silencing. However, several examples of atypical methylation were shown. In Paper I we present the ICSBP/IRF8 gene that belongs to the IRF family and has characteristics of a tumor suppressor gene. The ICSBP/IRF8 is fully methylated in the promoter and TSS regions in U-937 and despite high expression of the gene. Presence of positive histone marks suggests that methylated DNA can be overridden by histone modification. In Paper II a panel of 13 MM (multiple myeloma) cell lines and 9 primary patient tumors were analysed for methylation status of the ICSBP/IRF8 gene. In most cell lines (8/13) the gene was partially or fully methylated and partial methylation was also observed in 1/9 primary tumors. In vitro methylation analysis and treatment with 5-aza-2’deoxycytidine (DAC) proved that the ICSBP/IRF8 gene is silenced by methylation and may be associated with the malignant phenotype. In Paper III and IV the NFκB signalling pathway was analysed and the role of ATRA and TNFα induction. In Paper III the data shows that activation of the NFκB pathway is essential in ATRA-induced terminal differentiation in the U-937 cell line and IκBα (S32A/S36A) inhibits ATRA-induced differentiation and G1 cell cycle arrest. This was accompanied by delayed down-regulation of several cyclins (A and E) and up-regulation of p21WAF1/CIP1 (CDKN1A) and p27KIP1 (CDKN1B). TNFα alone did not induce expression of RA-induced genes analysed in Paper IV. However, ATRA in combination with TNFα showed enhanced activation of RA-induced genes. TNFα triggers demethylation of H3K9me3/H3K9me2 and H3K4me3 at RAR/RXR target genes, which were not accompanied by changes in the level of H3K9-ac. This decrease in H3 methylation by TNFα may pave way for the later ATRA-induced gene transcription.
27

Klassrumssamtalets mönster och betydelse

Nerbring, Jens Thomas January 2017 (has links)
With a growing demand from the latest curriculum this study aims to investigate what classroom talk looks like at a school in Sweden. Through observations in different classrooms and interviews with experienced teachers I seek to investigate and map out classroom talk structures, how teachers relate to classroom talk, what kind of questions the teachers ask and how they follow up the students´ answers. Inspired by Vygotskij´s “zone of proximal development” the study takes on a sociocultural perspective and focuses on social interaction. Both qualitative and quantitative research methods are used. The focus of the study is on the type of questions the teachers are using and how they follow up the answers from the students. The results tell us that that the teachers are using a lot of open questions and the answers from the students are often long, something which differs from earlier research. The collected data from interviews as well as from observations hints that the teachers are aware and make conscious decisions when they decide what type of questionsthey ask their students. When looking at how the teachers follow up the students´ answers the results shows that it´s rare that the teachers follow up and further develop the students answers.
28

Characterization of Lamps of IRF Solar Simulator

Sonna, Mrunmayee January 2023 (has links)
The Swedish Institute of Space Physics (IRF) at Kiruna focuses on research activities in the ionosphere, magnetosphere, and upper atmosphere of the planet as well as the development and production of various sensors and detectors for space research. The test facility includes the IRF SpaceLab which is equipped with multiple testing equipment. One of the testing resources available is the Solar Simulator, which consists of a vacuum chamber equipped with four metal halide lamps that produce a spectrum closely resembling that of the Sun. When any spacecraft payload or instrument is exposed to the Sun and its radiations, the most important factors to consider are the type of radiation, flux, and how the exposed material will react. Thermal designing and solar balance tests are important factors in achieving expected conditions for different missions. By testing and verifying these lamps, this solar simulator can be used not only for IRF missions but also for other institutes and private organizations that can access it. The characterization of four lamps is done in terms of temperature distribution, radiation, and power. According to preliminary experimental measured values obtained from the setup, exposed material, and its properties can be varied and the best suitable coating can be selected that includes α (absorptivity) and ϵ (emissivity) valueconsideration. The thesis is divided into four phases: Designing, Manufacturing, Testing, and Analyzing. Before entering into these phases, the basic knowledge of thermal engineering and thermal simulation is acquired. Thermal modeling and simulations are done in Airbus Defence &amp; Space’s Systema Thermica software tool. The design phase includes designing a frame structure and a 350 x 350 mm screen in Autodesk Inventor software. Manufacturing of the frame structure and the screen was done in the IRF workshop. This screen kept hanging with the support of a frame structure which is mounted on the copper table inside the chamber. The screen is kept in the field of view of each lamp and every lamp is illuminated accordingly. The analysis is done by measuring the temperature of the back side of the screen. Temperature sensors were mounted and clamped mechanically instead of kapton tape to avoid direct contact with the screen. The obtained values are analyzed and compared with the thermally simulated values. Pressure and the temperature of the system were monitored with independent systems throughout the test procedure. This thesis report could operate as a foundation for future examination of the solar simulator’s lamps in order to determine precise efficiency.
29

Defining the molecular role of RNA helicase DDX3 in antiviral signaling pathways / RNAヘリカーゼDDX3の抗ウイルス性シグナル伝達経路における分子的役割の解明

SAIKRUANG, WILAIPORN 23 May 2022 (has links)
京都大学 / 新制・課程博士 / 博士(生命科学) / 甲第24119号 / 生博第481号 / 新制||生||64(附属図書館) / 京都大学大学院生命科学研究科統合生命科学専攻 / (主査)教授 野田 岳志, 教授 鈴木 淳, 教授 高田 穣 / 学位規則第4条第1項該当 / Doctor of Philosophy in Life Sciences / Kyoto University / DFAM
30

Oral Corrective Feedback Practices in Third Turns of Initiation-Response-Feedback Sequences : An investigation into the Swedish context

Lind, Kajsa January 2024 (has links)
This study aims to expand on the existing research regarding teachers’ oral feedback practices in third turns of initiation-response-feedback (IRF) sequences. There is a gap in the existing research on oral corrective feedback practices in third turns of IRF sequences in the context of Swedish upper secondary school. The aim of this study is to fill some of that gap by providing results and insights from the Swedish context of upper secondary school. A classroom audio recording of a teacher’s classroom talk from an English class with second year students was subjected to conversation analysis to discover general patterns of this teacher’s oral corrective feedback practices in the third turn of IRF sequences. It emerged that implicit corrective feedback practices were frequent, with conversational recasts being among the most common types of feedback. The result of this study thus turned out to be in line with what previous research had found to be common oral corrective feedback practices among teachers.

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