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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.
421

The spatial organization of the epidermal growth factor receptor on the surface of colorectal carcinoma cells

Fournier, Charlotte January 2015 (has links)
The discovery of the existence of the cell membrane has led to a search for its organization on a molecular scale. The advent of artificial lipid bilayers and the development of electron microscopy in the 1930's provided direct visual evidence for the existence of the cell membrane and drove forward models of membrane structure based its known composition of proteins, lipids and carbohydrates. The fluid mosaic model of membrane structure, based on thermo- dynamics and newly developed protein structural studies of the time, placed integral globular membrane proteins within a fluid phospholipid bilayer. This model allowed for the association of proteins into groups and the possible mobility of proteins within the lipid bilayer. At the the same time fluorescence microscopy demonstrated movement of proteins in the plane of the lipid bilayer. Since then experimental techniques have been developed that show protein complexes of varying sizes do exist and so this gives us the opportunity to ask how receptor proteins fit into the molecular organization of the cell membrane. This thesis presents an investigation into how the epidermal growth factor receptor (EGFR) organizes in the cell membrane of colorectal carcinoma cells. First a new cell line for studying the receptor by stably expressing the epidermal growth factor receptor conjugated to enhanced green fluorescent protein (EGFR-eGFP) in SW620 cells was developed. This is an interest- ing cell line because it originates from a colonic adenocarcinoma that during the process of metastasis has lost the ability to express the EGFR. It therefore provided an environment for the expression of the fluorescent form of the receptor more in keeping with its natural environment. The technique of total internal reflection fluorescence (TIRF) microscopy was used to visualize the fluorescently tagged receptor in the cell membrane. This technique uses the principles of total internal reflection to excite fluorescence in molecules located only 100 nm into the cell. Because sources of fluorescence from outside the illuminated area are minimized individual fluorescent molecules can be imaged. The spots in the images, produced by the fluorophores, were detected using a single molecule detection and tracking algorithm. The intensities of these detected spots were analysed and compared with that from a single molecule of enhanced green fluorescent protein (eGFP). This gave an estimate of the number of receptors contained within each receptor complex. Before ligand binding most of the receptors were found to be located in complexes containing up to eight molecules and most frequently they were found in complexes of two molecules. Larger complexes of receptors were found to have formed after activation of the receptor by its ligand.
422

Temporal Abstraction : Creating the means for inducing reflection

Parr-Young, Robert Henry January 2018 (has links)
No description available.
423

Guiding Preservice Teachers to Critically Reflect: Towards a Renewed Sense about English Learners

January 2011 (has links)
abstract: The purpose of this practitioner inquiry was to explore the use of Guided Critical Reflection (GCR) in preparing preservice teachers for English learners (ELs). As a teacher researcher, I documented, analyzed, and discussed the ways in which students in my course used the process of GCR to transform their passively held understandings about ELs. Specifically, the research questions were: 1) What are preservice teachers' common sense about teaching and learning related to ELs? 2) How does GCR transform preservice teachers' common sense about ELs? 3) What is my role as an educator in creating opportunities for GCR? I utilized methods for data collection that fit my teaching practices. Data sources included three types of observations (self-reflective field notes, audio recordings of each class, and notes documented by an outside observer), student-work artifacts, and my audio reflection journal. I analyzed data inductively and deductively using a modified analytic induction approach. Building on previous research concerning the use of reflection in teacher preparation, I define GCR as the process in which I guided preservice teachers to acknowledge and examine their common sense about ELs, reframe what they know in light of course learning, and transform their understandings. Five major findings emerged from this study. First, preservice teachers entered the course with common sense notions about ELs rooted in their educational and life experiences. Students felt comfortable sharing what they knew about ELs, but needed to be scaffolded to examine how their life experiences shaped their common sense. Within the course, preservice teachers framed and reframed their common sense in different ways. Through the process of GCR, students evidenced a renewed sense about ELs. Finally, my role as a teacher involved establishing a comfortable learning environment, valuing my students' common sense as the catalyst for course learning, and guiding students through their reflective work. Ultimately, I was able to create opportunities for GCR because I too was reflecting on my practices, just as I was asking my students to reflect on their common sense about ELs. / Dissertation/Thesis / Ph.D. Curriculum and Instruction 2011
424

Analysis of biomarkers of age-related diseases by total internal reflection fluorescence microscopy

Chan, Hei Nga 01 June 2018 (has links)
Total internal reflection fluorescence microscopy (TIRFM) has been widely applied for the study of biomolecules because of their ability to quantify biomolecules in a sample pretreatment and enrichment free manner, when compared with those costly, sample consuming and labor intensive conventional detection assay. Here, we have applied the TIRFM imaging system for the direct quantification and analysis of the biomarkers for the age-related diseases. Three research works on the quantification and study of biomarkers with the aid of TIRFM were herein described.
425

GIVING STUDENTS THE REINS: TAKING ADVANTAGE OF SERVICE-LEARNING'S POTENTIAL AS A PEDAGOGY FOR TEACHING WRITING

Kramer, Tereza Joy 01 May 2012 (has links)
Service-learning helps students experience the practical applications of learning to write well; it also offers opportunities for students to develop a sense of civic responsibility. Although service-learning is growing in popularity, this pedagogy is not prevalent in English departments. Additionally, service-learning courses across all disciplines typically do not empower students to make their own project decisions. Given these tendencies, it is useful to consider whether service-learning is an effective pedagogy for writing, whether students should be designing their own projects, and what writing instructors could do to facilitate students' growth as writers while completing projects in the community. This is a qualitative case study, incorporating quantitative data, of two technical writing courses. I reviewed the students' answers to surveys developed for this research, plus their course evaluations, individual reflective writing, and collaborative project documents, and then I compiled and collated the students' references to what they were learning and what they were struggling with. The references fall within the following themes: student decision-making; the role of the instructor; the rhetorical tenets of audience and purpose; service; collaboration with peers and community members; written expression; and professionalism and motivation. Relying upon the students' comments in regard to these themes, I suggest that service-learning can help students become invested in the outcome of their written expression, motivating them to learn how to address audience and purpose through strong writing. Students learn to work collaboratively and develop their own individual voices as they discover, reflect upon, and express their ideas and shared knowledge. Instructors should ask students to design their own projects, allowing them to engage with and learn how to contribute to the community: through self-directed experiential projects, students become more likely to understand the power of writing and to transfer their new knowledge to later situations. I conclude with a discussion of the need for targeted research and suggestions for teaching writing through community-based pedagogy to enhance civic engagement.
426

Circularly polarised optics in Scarabaeidae

McDonald, Luke Thompson January 2016 (has links)
In nature, both fundamental and sophisticated ecological functionality alike are driven by the display or, conversely, the concealment of colour and visual contrast. Through scientific investigation, the evolutionary genius manifested in numerous light manipulating biological systems has provided many blueprints for innovative photonic devices and other smart materials. The development of innovative bioinspired materials that harness the optical properties exhibited by chiral structures, such as those found in certain Scarabaeidae, offer widespread potential. In this thesis, the species-specific circularly polarised optical behaviour corresponding to a variety of Scarabaeidae beetles is investigated. The helicoidal morphology giving rise to circularly polarised photonic properties is first described for several beetles displaying a narrowband colour appearance. A structural analysis of the native surface structures encountered in these species is presented alongside a discussion of their role in defining the species' optical characteristics. Experimental measurements of the circularly polarised scattering behaviour are presented and discussed with respect to the electron microscopy and surface morphology measurements comprising the structural analysis. Following this, the origins of the subtle differences in the metallic colour appearance of several broadband coleopteran structures are deciphered. The broadband response of these species is attributed to chirped configurations of the helicoidal lamellar structure, elucidated using electron microscopy. Results of this structural analysis are applied to theoretical simulations of the structures' electromagnetic response and consolidate experimental measurements of the circularly polarised reflectance. Rigorous experimental measurement demonstrated that the circularly polarised spectral response is relatively robust to small structural defects or `biological noise'. Building from this, the intraspecific colour variation displayed in the species Chrysina aurigans is a useful lens through which the nuances of the chirped multilayer structure are further examined. As a result, this work provides detailed insights into the fine-tuning of chirped biological photonic systems. Likewise, the topic of biological wave retarders is afforded significant attention, primarily with reference to the biological half-wave plate encountered in the cuticle structure of Chrysina resplendens. A rigorous analysis of the photonic system in C. resplendens is presented, leading to novel conclusions describing this system's opto-structural relationship. Additionally, this thesis reports, for the first time, the presence of a biological wave retarder in the cuticle structure of Chrysina cupreomarginata.
427

The Effect of Teaching with Stories on Associate Degree Nursing Students' approach to Learning and Reflective Practice

January 2012 (has links)
abstract: This action research study is the culmination of several action cycles investigating cognitive information processing and learning strategies based on students approach to learning theory and assessing students' meta-cognitive learning, motivation, and reflective development suggestive of deep learning. The study introduces a reading assignment as an integrative teaching method with the purpose of challenging students' assumptions and requiring them to think from multiple perspectives thus influencing deep learning. The hypothesis is that students who are required to critically reflect on their own perceptions will develop the deep learning skills needed in the 21st century. Pre and post surveys were used to assess for changes in students' preferred approach to learning and reflective practice styles. Qualitative data was collected in the form of student stories and student literature circle transcripts to further describe student perceptions of the experience. Results indicate stories that include examples of critical reflection may influence students to use more transformational types of reflective learning actions. Approximately fifty percent of the students in the course increased their preference for deep learning by the end of the course. Further research is needed to determine the effect of narratives on student preferences for deep learning. / Dissertation/Thesis / Ed.D. Leadership and Innovation 2012
428

Hra a výchova / Game and upbringing

KUŠNIRENKOVÁ, Viktorie January 2015 (has links)
Diploma work engaged game and upbringing, if is there interconnection and continuity. In this work are three main chapter. First chapter apply upbringing. Then follow second charter about game. Third charter´s name is "Upbringing like process and upbringing like game".
429

Výuka shodných zobrazení na prvním stupni ZŠ s využitím origami / Teaching geometry at primary school using origami.

KOLÁŘOVÁ, Magdalena January 2017 (has links)
The master's thesis Teaching geometry at primary school using origami is focused to increasing symmetry knowlidges, especially to reflection symmetry and central symmetry. The thesis contains analysing maths textbooks. It deals with creating worksheets and metodology of them and evaluation of tested worksheets.
430

Análise de ocorrência de metamerismo em revestimentos cerâmicos

Maccari Neto, Alfredo January 2009 (has links)
Um dos problemas técnicos que ocorrem nos revestimentos cerâmicos é a possibilidade de duas peças serem da mesma cor sob a luz do dia, mas de cores diferentes sob outra iluminação. Tal fenômeno é chamado metamerismo. O presente trabalho teve como objetivo realizar um estudo sobre a influência de variáveis do processo de fabricação de revestimentos cerâmicos na ocorrência do fenômeno de metamerismo, tendo como objeto de estudo uma peça monoporosa de esmalte branco-brilhante, e um porcelanato mate. Para tanto, avaliou-se o efeito da variação de iluminante, correlacionado com as seguintes características dos revestimentos cerâmicos investigados: i) tipologia de esmalte; ii) base, engobe esmaltes; iii) variação de camada; iv) utilização de quartzo, caulim e zirconita; v) variação de corantes. Os resultados mostraram que esmaltes, como o branco-brilhante, se destacam no aparecimento da característica metamérica, tanto mais quanto mais espessa a camada. Já, quando se aumenta a camada do mate, este fenômeno ameniza. A zirconita, por ser um opacificante, ameniza a reflexão da luz, gerando uma diminuição do metamerismo. O quartzo promove o metamerismo, já que influencia no aparecimento do brilho. Quanto aos corantes, pigmentos que amenizam o reflexo da luz, como o preto e cinza, possuem um valor metamérico baixo, já pigmentos que tendem ao reflexo maior da luz, promovem o metamerismo. Com base nisso, o suporte do porcelanato esmaltado que se apresenta em uma base cinza, possui um valor metamérico menor que a base da monoporosa, que possui uma cor bege. Ficou evidenciada a influência das curvas espectrais e do reflexo no aparecimento do metamerismo, podendo ser um ponto crucial para que empresas trabalhem em cima deste problema, a fim de ser um diferencial para seus clientes no mercado competitivo como o de hoje. / One of several problems that occur in ceramic tiles, is the possibility that two objects are the same color in the light of day, but of different colors in a different light. This phenomenon, in which two colors are similar under a light source but different under another, is called metamerism. Seeking a study on this phenomenon was analyzed the influence of some variables on the metamerism in a white enamel-bright monoporosity, and a matte porcelain. Some of the variables selected for the study of the influence of the media, and enamel on engobe metamerism, the addition of opacifier material, in suspension and bright enamels in different percentages, the analysis with the addition of pure colors and mixtures of the same in glazes; variations in the enamel layer, among other factors. Before, it was noticed that the enamel provide a high spectral curve, ie, materials that reflect the highly light, tend to influence the onset of this phenomenon. Thus, materials that influence the formation of brightness as quartz help this phenomenon to emerge since opacifying materials that have the feature to break it brightness, ie, which have lower spectral curves, decreases the appearance of this phenomenon. In the matter of color is the same as explained above, ie, pigments that mitigate the reflection of light as the black and gray, have a low value metameric because colors tend to reflect more light, raise this value. On this basis, the support of porcelain enamel that comes in on a gray metameric has a value less than the base of monoporosity, which has a beige color. Having knowledge of these factors, it is clear the influence of spectral curves and reflex formed by these variables in the emergence of this phenomenon and may be a crucial point for companies to work upon this problem, in order to be a differentiator for its customers in competitive market which is today.

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