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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.
1

Kommunikationsmönster i förskolans styrda aktiviteter. / Communication patterns in preschool- teacher directed activities.

Johansson, Madeléne January 2017 (has links)
Nationell och internationell forskning belyser interaktionen och kommunikationen som en viktigt del i undervisningen. Pedagogernas kommunikativa förmåga är en central del i framgången till att uppnå förskolans mål. Syftet med studien är att undersöka kommunikationen mellan pedagoger och barn i styrda aktiviteter på förskolan. Fokus i studien ligger på pedagoger och barns kommunikation i förskolans styrda aktiviteter som knyter an till IRE/IRU- modellerna och den samtalsanalytiska diskursen. Studien belyser tre centrala delar: sociala samspel, autentiska frågor och uppbackningar i samtalet. Resultatet visade att beroende på vilken typ av interaktion pedagoger valde, påverkade det undervisningens kvalité.Undersökningen baseras på en kvalitativ metod och studiens syfte är att belysa vilken kommunikation som uppstår mellan pedagoger och barn i styrda aktiviteter. Valet av metoden föll på etnografi som gav mig utrymme att tolka individers handlingar. För att kunna studera fenomenet valdes observationer som ett lämpligt verktyg och genom dessa har jag kunna se hur kommunikationen utformas i styrda aktiviteter. Valet av metod motiveras genom att observera de styrda aktiviteterna på ett objektivt vis, och på så sätt som utomstående kunna se det som sker i de styrda aktiviteterna mellan pedagoger och barn.
2

Kommunikation och relation mellan lärare-elev i matematikundervisning : En studie om hur kommunikation används i matematikundervisning, samt hur lärare kan arbeta för att etablera relationer till sina elever i högstadiet åk 7–9 / Communication and Relationship between Teacher-Student in Mathematics Education

Hamasor, Kizhan January 2018 (has links)
No description available.
3

Dynamik i klassrumssamtal : En studie om när och hur samtal initieras i en femmas klassrum / Dynamics in classroom conversations : A study of how and when conversations are initiated in a fifth grade classroom

Söderström, Nicole January 2013 (has links)
Vi lever idag i ett kommunikationsrikt samhälle där vi har möjlighet att dagligen delta i och höra ett flertal samtal. Samtalen kan vara av både formell och informell karaktär och kräver olika ansträngningar av oss. Av de här anledningarna vore det naturligt att vi övar oss i att samtala i skolan, speciellt eftersom mycket tyder på att samtal är en förutsättning för lärande. Syftet med den här studien är således att öka kunskap om hur samtal inleds i ett klassrum i svensk skola.   Ämnet har undersökts genom att videofilma fyra lektioner i en femteklass och därefter analysera materialet med hjälp av konversationsanalys (CA). Samtalsdeltagarna har varit de 21 elever, i åldrarna 11-12 år, som ingår i klassen och deras klasslärare. Resultatet visar bland annat att skillnader i typ av lektion påverkar vem som får tala. Under de lektioner som präglas av helklassdiskussioner tar läraren oftare initiativ till samtal och under sådana lektioner där eleverna arbetar självständigt inleder de oftare samtal. Slutligen kan sägas att mycket av elevernas möjlighet att initiera samtal påverkas av lärarens implicita metoder för att organisera undervisningen.
4

Computational characterization of IRE-regulated genes in Glossina morsitans

Dashti, Zahra Jalali Sefid January 2013 (has links)
Philosophiae Doctor - PhD / Blood feeding is a habit exhibited by many insects. Considering the devastating impact of these insects on human health, it is important to focus research on understanding the biology behind blood-feeding, disease transmission and host-pathogen interactions. Such knowledge would pave the way for developing efficient preventative measures. Iron an important element for species survival, is at the center of events controlling tsetse’s fitness and reproductive success. Hence, targeting genes involved in iron trafficking and sequestration would present possible means of preventing disease transmission. Considering the dynamic and multi-factorial nature of iron metabolism, a well-coordinated regulatory system is expected to be at work. Despite extensive literature on the mechanism of iron regulation and key factors responsible in maintaining its homeostasis in human, less attention has been given to understand such system in insects, especially the blood-feeding insects. The availability of the genome sequences for several insect disease vectors allows for a more detailed analysis on the identification and characterization of events controlling and preventing iron-induced toxicity following a blood-meal. The International Glossina Genome Initiative (IGGI) has coordinated the sequencing and annotation of the Glossina morsitans genome that has led to the identification of 12220 genes. This knowledge-base along with current understanding of the IRE system in regulating iron metabolism, allowed for investigating the UTRs of Glossina genes for the presence of these elements. Using a combination of motif enrichment and IRE-stem loop structure prediction, an IRE-mediated regulation was inferred for 150 genes, among which, 72 were identified with 5’-IREs and 78 with 3’-IREs. Of the identified IRE-regulated genes, the ferritin heavy chain and MRCK-alpha are the only known genes to have IREs, while the rest are novel genes for which putative roles in regulating iron levels in tsetse fly have been assigned in this study. Moreover, the functional inference of the identified genes further points to the enrichment of transcription and translation. Furthermore, several hypothetical proteins with no defined functions were identified to be IRE-regulated. These include TMP007137, TMP009128, TMP002546, TMP002921, TMP003628, TMP004581, TMP008259, TMP012389, TMP005219, TMP005827, TMP007908, TMP009332, TMP01- 3384, TMP009102, TMP010544, TMP010707, TMP004292, TMP006517, TMP014030, TMP009821 and TMP003060 for which an iron-regulatory mechanism of action may be inferred. We further report 26 IRE-regulated secreted proteins in Glossina, that present good candidates for further investigation pertaining to the development of novel vector control strategies. Using the predicted data on the identified IRE-regulated genes and their functional classification, we derived at 29 genes with putative roles in iron trafficking, where several unknown and hypothetical proteins are included. Thus a novel role is inferred for these genes in cellular binding and transport in the context of iron metabolism. It is therefore possible that these genes may have evolved in Glossina, such that they compensate for the absence of an IRE- regulated mechanism for transferrin. Additionally, we propose 14 IRE-regulated genes involved in immune and stress response, which may indeed play crucial roles at the host pathogen interface through their possible mechanisms of iron sequestration. Using the subcellular localization analysis, we further categorized the putative IRE regulated genes into several subcellular localizations, where the majority of genes were found within the nucleus and the cytosol. The detection of the conserved motifs in a set of genes, is an interesting yet sophisticated area of research, that allows for identifying either co-regulated or orthologous genes, while further providing support for the putative function of a set of genes that would otherwise remain uncharacterized. This is based on the notion that co-regulated genes are often coexpressed to carry out a specific function. As such, 14 regulatory elements were identified in the 5’- and 3’-UTRs of IRE-regulated genes, involved in embryonic development and reproduction, inflammation and immune response, signaling pathways and neurogenesis as well as DNA repair. This study further proposes several IRE-regulated genes as targets for micro-RNA regulation through identifying micro-RNA binding sites in their 3’UTRs. Using a motif clustering approach we clustered IRE-regulated genes based on the number of motifs they share. Significantly co-regulated genes sharing two or more motifs were determined as critical targets for future investigation. The expression map of IRE-regulated genes was analyzed to better understand the events taking place from 3 hours to 15 days following a blood meal. Re-analysis of Anopheles microarray chip showed the significant expression of three cell envelope and transport genes as early response and six as late response to a blood meal, which could indeed be assigned a putative role in iron trafficking. Genes identified in this study with implications in iron metabolism, whose timely expression allows for maintaining iron homeostasis, represent good targets for future work. Considering the important role of evolution in species adaptation to habits such as Hematophagy, it is of importance to identify evolutionary signatures associated with these changes. To distinguish between evolutionary forces that are specific to iron-metabolism in blood-feeding insects and those that are found in other insects, the IRE-regulated genes were clustered into orthologous groups using several blood feeding and non-blood feeding insect species. Assessment of different evolutionary scenarios using the Maximum Likelihood (ML) approach, points to variations in the evolution of IRE-regulated genes between the two insect groups, whereby several genes indicate an increased mutation rate in the BF-insect group relative to their non-blood feeding insect counterparts. These include TMP003602 (phosphoinositide3-kinase), TMP009157 (ubiquitin-conjugating enzyme9), TMP010317 (general transcription factor IIH subunit1), TMP011104 (serine-pyruvate mitochondrial), TMP013137 (pentatricopeptide Transcription and translation), TMP013886 (tRNA(uridine-2-o-)-methyl-transferase-trm7) and TMP014187 (mediator 100kD). Additionally, we have indicated the presence of positively selected sites within seven blood-feeding IRE-regulated genes namely TMP002520 (nucleoporin), TMP008942 (eukaryotic translation initiation factor 3), TMP009871(bruno-3 transcript) , TMP010317 (general transcription factor IIH subunit1), TMP010673 (ferritin heavy-chain protein), TMP011104 (serine-pyruvate mitochondrial) and TMP011448 (brain chitinase and chia). Thus the results of this study provides an in depth understanding of iron metabolism in Glossina morsitans and confers important targets for future validations based on which innovative control strategies may be designed.
5

Identification and characterization of an incomplete root hair elongation (IRE)-like gene in Medicago truncatula (L.) root nodules.

Pislariu, Catalina Iulia 05 1900 (has links)
Cloning and molecular characterization of new genes constitutes a useful approach in studying the symbiotic interactions between the model plant Medicago truncatula and Synorhizobium meliloti. Large numbers of expressed sequence tags (ESTs) available for Medicago truncatula, along with numerous cDNA, oligonucleotides, and Affimetrix DNA microarray chips, represent useful tools for gene discovery. In an attempt to identify a new gene that might be involved in the process of nodulation in Medicago truncatula, preliminary data reported by Fedorova et al. (2002), who identified 340 putative gene products or tentative consensus sequences (TCs) expressed only in nodules, was used. This research was focused on TC33166 (TC103185), which has 3 ESTs in the TC, and whose strongest BLASTX hit of TC103185 is the incomplete root hair elongation (IRE) protein kinase-like protein (NP_192429) from Arabidopsis thaliana. The Arabidopsis IRE gene is required for normal root hair growth, and a role in apical growth was suggested (Oyama et al., 2002). Infection thread growth can be looked at as an inward growth of the root hair. Thus, TC103185 was a good candidate for identifying a gene that may be involved in early events of nodulation. MtIRE (GenBank accession AC122727) is organized in 17 exons and 16 introns, similarly to the Arabidopsis IRE gene. MtIRE is a new member of the IRE family and it is a putative Ser/Thr protein kinase. MtIRE is a nodule- and flower-specific gene, suggesting that nodulation may have recruited it from other developmental processes. MtIRE is likely to be involved in the invasion process, or in the maturation of the symbiosome, or of the cells that contain rhizobia, rather than infection thread initiation and elongation or in nitrogen fixation. Nodule invasion precedes the onset of MtIRE expression and the expression pattern changes in time within the nodule. RNA interference results support MtIRE expression data and suggest a possible role in preventing extensive defense responses. Our study demonstrates the existence of an Arabidopsis IRE homolog in Medicago truncatula root nodules with an entirely new function and regulation.
6

An Investigation of Thermal Mitigation Strategies for Electroporation-Based Therapies

O'Brien, Timothy J. 16 July 2019 (has links)
Irreversible electroporation (IRE) is an energy directed focal ablation technique. This procedure typically involves the placement of two or more electrodes into, or around, a region of interest within the tissue and administering a sequence of short, intense, pulsed electric fields (PEFs). The application of these PEFs results in an increase in the transmembrane potential of all cells within the electric field above a critical value, destabilizing the lipid bilayer of the cellular membrane and increasing the cell-tissue permeability. For years, many have used this phenomenon to assist the transport of macromolecules typically unable to penetrate the cell membrane with the intent of avoiding cell necrosis or irreversible electroporation. More recently, however, irreversible electroporation has proven to be a successful alternative for the treatment of cancer. Proper tuning of the pulse parameters has allowed for a targeted treatment of localized tumors, and has shown immense value in the treatment of surgically inoperable tumors located near major blood vessels and nerves. While it is critical to ensure sufficient treatment of the target tissue, it can be equally vital to the treatment and patients overall outcome that the pulsing conditions are set to moderate the associated thermal effects with the electroporation of biological tissue. The development of thermal mitigation strategies for IRE treatment is the focus of this dissertation. Herein, the underlying theory and thermal considerations of tissue electroporation in various scenarios are described. Additionally, new thermal mitigation approaches with the intention of maintaining tissue temperature below a thermally damaging threshold, while also preserving or improving IRE lesion volume are detailed. Further, numerical models were developed and ex vivo tissue experiments performed using a perfused organ model to examine three thermal mitigation strategies in their ability to moderate temperature. Tests conducted using thermally mitigating treatment delivery on live tissue confirm the capacity to deliver more energy to the tissue at a thermally acceptable temperature, and provide the potential for a replete IRE lesion. / Doctor of Philosophy / Irreversible electroporation (IRE) is a minimally invasive therapy utilized to treat a variety of cancers. This procedure involves the delivery energy in the form of pulsed electric fields (PEFs) through two or more needle electrodes. These PEFs destabilize the cell membrane, increase the cell-tissue permeability, and ultimately induce cell death for any given cell within the targeted treatment region. Over the years, this treatment modality has shown a great deal of promise in the treatment of unresectable tumors in which the tumor is positioned near or around sensitive regions making the surgical removal of the tumor impossible and thermal ablation techniques limited in their ability to treat without irrevocably damaging the underlying tissue architecture and other critical surrounding structures. Thus, it can be vital to the treatment and patients overall outcome that the IRE therapy is set to moderate any associated thermal effects with the electroporation of biological tissue. However, the design of an electric field that simultaneously maps the entire region of interest for a single treatment and avoids undesirable thermal effects can be challenging when treating larger or irregularly shaped volumes of tissue. Thus, in this dissertation, we demonstrate various treatment delivery methods/ enhancements to reduce temperature rise during IRE therapy. The underlying theory of tissue electroporation and associated thermal considerations are described to provide a foundation and general context. Additionally, novel approaches to tissue electroporation therapy with the intention of maintaining tissue temperature below a thermally damaging threshold throughout treatment are detailed.
7

High-Frequency Irreversible Electroporation (H-FIRE) optimization for the treatment of highly invasive cells beyond the tumor margin

Latouche, Eduardo L. 19 June 2016 (has links)
Irreversible electroporation (IRE) is a non-thermal ablation technique that allows for eradication of unresectable tumors in a minimally invasive procedure. While IRE will preferentially kill larger cells over smaller ones, it does not discriminate between cells with larger and small nuclei. Given that one of the hallmarks of cancer cell morphology is larger, more abundant nuclei, our team set out to explore the possibility of preferentially targeting this physical and geometrical characteristic. / Master of Science
8

Význam sialovaných glykoproteinů pro klíště \kur{Ixodes ricinus}

ONDRUŠ, Jaroslav January 2016 (has links)
Sialic acid is a highly abundant and a common component of vertebrate glycans, where it can be found in the terminal positions of the cell surface glycoconjugates. The amount of sialylated glycoconjugates as well as their complexity vary between both different species and different tissue types within one individual. Considering the vertebrates, these well studied structures are know to be important for cell-cell interactions, cell adhesion and immunity. In contrary, sialic acid in arthropod glycans has been identified only in a limited number of species. In obligatory blood feeding parasites such as ticks, distinguishing between sialylated glycoproteins of tick and host origin is challenging due to huge volumes of ingested blood containing heavily sialylated structures of host origin. In the tick Ixodes ricinus, the presence of minor amount of tick´s sialylated structures has been shown previously in the ovaries and salivary glands, however, their role remains completely unknown. In this thesis, we study the importance and role of both the tick-originating and the host sialylated glycoproteins for I. ricinus, the tick commonly found in Czech Republic. We show that the tick-originating sialylated glycoproteins are present in I. ricinus eggs, and that their amount changes over time after laying the eggs. Furthermore, these molecules were localized in cryosections of 14 days old eggs and in the larvae using confocal microscopy. In addition, we shed some further light on the role of sialic acid for ticks in the tick blood meal. According to our results, the glycan part of glycoproteins is the key in recognition of these molecules by tick cells.
9

Är du nöjd med din vänstersväng? : En kvalitativ studie om kommunikation och lärande i en trafiklektion / Are you pleased with your left turn? : A qualitative study on communication and learning during a driving lesson

Manoukian, Dory January 2017 (has links)
Kommunikation och lärande i körlektioner är ett område inom forskning som det inte finns alltför mycket studier kring. Denna studie ämnar belysa hur kommunikation och lärande kan te sig i en körlektion. Genom deltagande observation har ljudupptagning av en komplett körlektion gjorts vilken därefter transkriberats och analyserats. Frågeställningarna för arbetet har varit hur IRE-sekvenser används under körlektioner och hur de bidrar till körelevens lärande samt vilka sorters frågor som förekommer under körlektionen och vilken funktion dessa fyller. Resultaten visade att IRE-sekvenserna främst fick eleven att reflektera över sina färdigheter följt av ett längre inlägg från läraren. Beträffande frågorna ställdes det endast informationssökande sådana från eleven medan lärarens varierade mer med bland annat informationssökande och uppmärksamhetsväckande frågor. / Communication and learning in driving lessons is an area within research with limited extent. This paper aims to highlight in which way communication and learning can appear in a driving lesson. Through partaking observation, audio recording has been made of a complete driving lesson to transcribe and analyze it. The questions this paper aims to answer have been how IRE-sequences are used during driving lessons and how they contribute to the trainee driver’s learning and what kinds of questions that appear during the lesson and how they function. The results showed that the IRE-sequences were used primarily to have the trainee driver reflect over their own abilities followed by a longer learning sequence by the teacher. Concerning the questions, the trainee driver solely asked information seeking ones whereas the teacher’s questions varied more including information seeking and attention-grabbing questions.
10

Elevernas upplevelser avmatematiksamtal i helklass- En intervju- och observationsstudie i grundskolan

Norberg, Maria, Lagerlöf, Ida January 2021 (has links)
Studiens syfte är att bidra med en ökad förståelse av elevernas upplevelser av att delta imatematiska samtal i helklass. Arbetet tar avstamp i följande frågeställningar: Vad för slags deltagarmönster framträder i helklassamtal? Och Hur upplever elever delaktighet i matematiska samtal i helklass och vilka faktorer gör att delaktigheten upplevs så? Den metod som använts för att besvara syftet är semistrukturerad intervju samt observation. Studien genomfördes på en grundskola i tre olika klasser, samtliga i årskurs två. För att få en djupare förståelse av elevernas upplevelser valde vi att observera de klassrum som eleverna befann sig i under matematiklektionerna. Studien utgår från ett sociokulturellt perspektiv på lärande och de vårt ramverk vi utgått från är utforskande samtal. Studiens mest framträdande resultat visar att eleverna upplevde sitt deltagande som osäkert i matematiksamtal. De ville inte dela med sig av svar de var osäkra på samt tyckte att det var jobbigt att svara fel. Ett annat framträdande resultat var att två av eleverna upplevde praktiken som trygg. De hade inga problem med att dela med sig av svar de inte var säkra på och ansåg att de alltid hann tänka klart när läraren ställt en fråga. Faktorer som bidrog till elevernas upplevelser handlar om de frågor läraren ställer, att läraren endast väljer elever som räcker upp handen samt den korta betänketid som eleverna gavs. / The study aims to contribute an increased understanding of students´ experiences ofparticipating in mathematical whole-class conversations. The work is based on the following questions: What kind of participant pattern emerges in whole-class conversations? And How do students experience participation in mathematical whole-class conversations and what factors contribute? The method we used was semi-structured interviews with the students and observations during lessons in mathematics. The study was conducted at an elementary school in three different classes, all in grade two. To gain a deeper understanding of the students´ experience, we chose to study the environment they stayed in to relate their answers to the practice. The study is based on a socio-cultural perspective on learning and the framework we used is exploratory conversations. The study's most prominent results show that students experienced their participation as insecure in mathematics conversations. They did not want  to share answers they were unsure of and thought it was hard to answer incorrectly. Another result shows that two of the students experienced their participation as safe. They had no problem sharing answers they were not sure about and felt that they always had time to think when the teacher asked a question. Factors that contributed to the students' experiences are about the questions the teacher asks, focus on the right answer, that the teacher only chooses students who raise their hand, and the short reflection time that the students were given.

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