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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.
171

Some effects of tumour growth upon rat muscle protein metabolism

Raymond, Michael John January 1972 (has links)
The effect of the growth of the Walker 256 carcinoma upon various aspects of rat diaphragm protein metabolism was investigated. Microscopic examination of diaphragm muscle from tumour-bearing rats revealed that the mean muscle fibre diameter was reduced compared with the normal animal. The extracellular space of both 'cut' and 'intact' diaphragm preparations was measured, using sorbitol and inulin as extracellular markers. No differences were observed in the extracellular space of both types of diaphragm preparation from normal and tumour-bearing rats, using sorbitol as the marker. With inulin as marker, the extracellular space was much smaller in the 'cut' diaphragm preparation from the tumour-bearing animal. Quantitative analysis of diaphragm muscle showed that the muscle lost weight during the growth of the tumour and that part of the weight loss was due to the loss of protein. Further, the loss of contractile proteins appeared to be more extensive than the loss of sarcoplasmic proteins. The in vitro incorporation of H-lysine into mixed proteins of rat diaphragm was shown to be greatly reduced by the growth of the tumour. This effect seemed to be directed principally at the myofibrillar proteins. The inhibition was not alleviated by the addition of either high concentrations of lysine or a mixture of amino-acids to the incubation medium. Normal diaphragm muscles incubated in serum from a tumour-bearing rat exhibited a greatly decreased up-take of labelled lysine into the myofibrillar proteins, and this pattern was not altered by supplementation of the medium with a mixture of amino-acids. The stimulatory effect of insulin upon muscle protein synthesis was greatly reduced by the growth of the tumour. In the normal animals studied, the effect of insulin seemed to be directed principally towards the myofibrillar proteins. A toxohormone fraction was prepared from Walker tumour tissue by an acetic acid extraction method, and purified by cation-exchange chromatography and gel-filtration. The biological activity of the preparation was assayed by measurement of its effect upon the plasma iron level in mice. The effect of the purified toxohormone fraction upon muscle protein synthesis was investigated both in vivo and in vitro, and the toxohormone was observed to exert a profound inhibitory effect upon the incorporation of labelled lysine into mixed intracellular muscle proteins.
172

Protein-carbohydrate interactions

Moothoo, Davina Noelle January 1998 (has links)
Carbohydrates are ubiquitous in nature and have become the focus of much scientific investigation. The proteins which recognise carbohydrates have become widely used in the areas of cell and molecular biology. Protein - carbohydrate interactions have been probed by theoretical, structural and thermodynamic techniques. The lectins are a class of carbohydrate binding proteins which bind carbohydrates through non covalent interactions such as hydrogen bonds and van der Waals interactions. In addition to these interactions, other factors play an important role in determining affinity such as carbohydrate conformation, solvent reorganisation and changes in the protein binding site. The legume lectin concanavalin A specifically recognises mannose and glucose terminal residues. The thermodynamics of concanavalin A binding to carbohydrates has been well documented. Concanavalin A binds the core trimannoside and pentasaccharide of the biantennary glycan found on mammalian cell surfaces with a high affinity. This thesis describes the structural basis of carbohydrate binding by con A, through the interpretation of crystal structures of concanavalin A bound with α1-2 mannobiose, methyl α1-2 mannobioside, the core pentasaccharide of the biantennary glycan and fructose. The structural information obtained from these structures is related to thermodynamic information available and unravels the importance of the role played by carbohydrate conformation, solvent reorganisation and statistical population of ligand in determining affinity. This work helps to develop an understanding of the physical basis of carbohydrate recognition.
173

The preparation, properties and applications of nylon-tube immobilised catalase

Ashworth, Stuart D. January 1975 (has links)
1. Several nylon-tube immobilised catalase derivatives were prepared. The method of preparation of nylon-tube for enzyme attachment was varied in an attempt to obtain the most active immobilised catalase derivative. 2. The stability of nylon-tube immobilised catalase derivatives during constant perfusion with hydrogen peroxide was examined in an attempt to prepare the most stable immobilised enzyme. 3. The peroxidatic activity associated with nylon-tube immobilised catalase derivatives was investigated. The effect of the chemistry of immobilisation, the length and diameter of the nylon-tube, and methanol concentration on the peroxidatic : catalatic activity ratio displayed by the immobilised catalase derivatives. 4. The applications of nylon-tube immobilised catalase derivatives in automated analysis was considered. Glucose was determined by four different assay protocols, involving 1) nylon-tube co-immobilised glucose oxidase and catalathe ; 2) nylon-tube immobilised derivatives of glucose oxidase and catalase in series ; 3) nylon-tube immobilised derivatives of glucose oxidase, catalase, and aldehyde dehydrogenase in series ; 4) nylon-tube co-immobilised glucose oxidase and catalase in conjunction with an oxygen electrode. 5. The peroxidatic activity of catalase was monitored using a) Hantzsoh reaction ; b) Aldehyde dehydrogenase ; and c) flow-through oxygen electrode. The four analytical systems were calibrated with aqueous glucose standards and the assay sensitivity and immobilised enzyme stability determined. Comparisons were drawn between the four methods for glucose determination using nylon-tube immobilised enzymes.
174

Vermittlung der Grammatik im DaF-Unterricht an der Grundschule. Am Beispiel substantivischer Flexion / Pedagogical Technique in the Grammar of Noun Declension in German as a Foreign Language

JÁNSKÁ, Veronika January 2015 (has links)
This work is focused on a mediation of grammar in teaching of the German language in primary schools. The main attention is paid to the declension of nouns. I chose for the comparison two completely different outlined textbooks. In view of the fact, that still quite a large number of primary schools teaches according to the textbook "Heute haben wir Deutsch", I decided to confront this textbook with its more modern successor "Deutsch mit Max" and determine whether the conception of modern textbooks differ from those older ones only graphic, i. e. with illustration, and themes that correspond to the age of pupils, or with regard to grammar (the other choice, progression and quantity of grammar structures), and thus are these textbooks more suitable for the current teaching of the German language. Subsequently are the results of this work compared with the views of pupils who are taught according to these textbooks.
175

O livro escolar no Maranhão império: produção, circulação e prescrições

Velázquez Castellanos, Samuel Luis [UNESP] 27 March 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-03-27Bitstream added on 2014-06-13T18:43:42Z : No. of bitstreams: 1 velazquezcastellanos_sl_dr_arafcl.pdf: 3073880 bytes, checksum: 90a8312489b9436317d54482434a4420 (MD5) / Nesta pesquisa procurou-se compreender a representatividade dos livros escolares no Maranhão Império e a sua representação no ensino, tendo como recorte a sua produção e indicações de uso nas instituições escolares públicas e particulares de instrução primária e secundária. Procurou-se desvelar o universo do livro a partir dos jornais e dos seus agentes como os escritores, tipógrafos, redatores e colaboradores, que usaram este veículo para divulgarem suas idéias, criticar seus adversários e/ou se defenderem de diferentes formas de acusações e, para além disso, nos interessou em especial, verificar a importância da imprensa como lugar privilegiado da sociedade maranhense para reivindicar, criticar e oferecer para compra e doação, livros de diversa natureza e, em particular, os que se destinavam ao ensino das primeiras letras e das cadeiras ensinadas no secundário, com relevo ao Liceu Maranhense. Tratou-se de relacionar a produção, a circulação e as indicações de uso dos livros a um leitor escolarizado, mas também se buscou compreender outros lugares de leitura, exterior às escolas, como o gabinete de leitura, as bibliotecas e as conferências populares e pedagógicas. Relacionou-se a produção, a distribuição e as prescrições dos livros a partir das necessidades e interesses prementes para a organização e o funcionamento das escolas, assim como para a uniformização dos saberes onde os livros exerciam particular importância nesse desiderato. Discorreu-se sobre o processo de adoção, aprovação ou rejeição dos livros pelos órgãos de competência do governo como a Congregação do Liceu ou o Conselho da Instrução Pública e os seus atores como os Presidentes da Província, os Inspetores da Instrução Pública, os Delegados Literários e os professores. Verificou-se a procedência, as temáticas... / With this research the candidate aimed at analysing the representation of school books in Maranhao Imperio, within the scope of their production and use at public and private primary and secondary schools. The candidate aimed at discovering the world of the book, based on newspapers and related activities as typography, redaction and contributors who use the book to a wide range of purposes. These include publicising their ideas; criticise their opponents and/or defend themselves from different prosecutions. It was interesting to verify the importance of the press as a privileged means of claiming, criticising and offering to sell different types of books e.g. the ones teaching to read and write and topics taught in secondary school. The candidate establishes a link between the production, transmission and use of books to an instructed reader. He also aimed to understand the scope of reading venues outside the school, e.g. the Gabinete Português de Leitura; a Biblioteca Pública Provincial and the private libraries; popular and educational gatherings, amid other social places. The candidate established a link between the production and distribution of school books based on its needs and underlying organisational and functional interests aimed at knowledge standardization. This research also covers the adoption, approval, replacement and veto of school books by Governmental bodies, e.g. Congregação do Liceu or Conselho da Instrução Pública and their stakeholders, particularly the Presidentes da Província, Inspetores da Instrução Pública, Delegados Literários and the teachers. The candidate verified the origin, the themes and the authors of the books used by the scholars in the 1800, notably the maranhenses who wrote books targeting that public. As a result reference is made to theoretical and methodological... (Complete abstract click electronic access below)
176

The extent and relevance of instrumentalism, constructivism and critical realism in high school physical science textbooks : a critical study

Jacoby, Brian Arthur January 1990 (has links)
Instrumentalism is a philosophy of science which holds that scientific theories are merely useful fictions for making computative predictions. Its pragmatic purpose of 'saving the appearances' downgrades the role of theory in science. Realists, on the other hand, take the implications of theories seriously. This study investigates the attributes of both instrumentalism and realism, taking theory as its point of departure. It is pointed out that constructivism is closely related to instrumentalism, both being forms of pragmatism. Since both tend to concoct and relinquish theories too easily, they tend to be relativist and subjectivist. It is therefore concluded that neither instrumentalism, nor constructivism, nor empiricism is sufficient for a rounded science education. What is needed is a type of realism which acknowledges both the empirical physical world 'out there' and the constructivist nature of scientific knowledge. The naive (empiricist) realism so prevalent in school science textbooks cannot do this. It is contended that critical realism, and especially that of Bernard Lonergan, can meet this requirement. Reality is more than what is given in sensory experience. Therefore, in order to help solve the problem of relativism and subjectivity inherent in constructivism, we need to revise our notion of reality and objectivity. Twenty-three selected British, American, South African, and African Third World high school physical science textbooks were examined in detail to determine the extent of an instrumentalist philosophy in them. They were subjected to several textual analyses, including one especially devised for this study. The results reveal that our high school physical science textbooks do indeed contain a high degree of instrumentalism. This study postulates that this instrumentalism may be used to help pupils move towards realism. However, this needs to be augmented by a full-blooded critical realist approach which takes theoretical entities seriously. One way of doing this is through the use of suitable material in the preface of every textbook. Not only should the dangers of instrumentalism (and naive constructivism) be pointed out, but the role of theory in science should be emphasised. This may be achieved by simulations to encourage growth of models and theories, historical case studies involving theory-development, and additional reading of scientists in action. Some examples of these are provided.
177

A handbook of fundamentals of music

Scott, Jane Claire 01 January 1951 (has links)
The object of this book is to provide the beginner with a background of musical experience to strengthen his own musicianship so that he may possess confidence in his own ability and venture to be a creative person. The work in this book is strictly preparatory and is intended as a starting point.
178

The articulation of the South African social formation with the teaching of English as a first language in the Cape Education Department

Volbrecht, Terry 15 December 2016 (has links)
No description available.
179

School textbooks and teachers' choices : a contextualizing and ethnographic study

Reynolds, Mary Jane January 1997 (has links)
Bibliography: pages 140-157. / This study provides evidence that most teachers choose their class textbooks haphazardly and without evaluating them. As a result, bad textbooks are as likely to be chosen and to succeed commercially as good ones are. One consequence of this is that many publishers and authors continue to get away with producing bad textbooks. The study begins by describing the context in which school textbooks are chosen. It gives an overview of the textbook's role, and concludes that it is an indispensable part of an effective education system, especially where other resources are lacking. The study then considers the degree to which South African textbooks fulfil their roles; it concludes that most textbooks in schools are poor, many being incomprehensible to their audiences, but attention is also drawn to some positive textbook development that has taken place. The study next considers how and why so many poor textbooks have been selected by educators: it summarises the part played by education departments and publishers, and reviews the state of textbook evaluation as a discipline. It concludes that South African educators are poorly equipped to evaluate and select textbooks. Against this background, the study describes an investigation of how teachers select textbooks for their classes. The findings are that choice is haphazard and that evaluation, in the rare instances when it takes place, is usually unsystematic and superficial. In conclusion, the study recommends that research into textbook development is done to provide a theoretical framework for effective evaluation, and that training and other support in textbook evaluation for teachers is established to improve selection practices. The study hypothesises that the resulting demand from a broad base of well-informed textbook-selectors in schools will give authors and publishers a more powerful incentive than any other pressures can to produce materials that withstand systematic, critical and wise evaluation.
180

A Cup of Tea Please - a studie of cultural representation in English textbooks

Loureiro, Lalita January 2011 (has links)
The aim of this essay is to study how cultures are presented in English textbooks for A-level students in Sweden. The aim is divided into three research questions, what does culture in English teaching mean, how is the English-speaking world presented in the textbooks and is the image that is presented stereotyped or does it try to challenge it?The study comprises of four textbooks from 1998-2008. The theoretical frame used in the essay is Edward Said’s Orientalism. Results show that much of the focus is on countries from the inner circle of the English-speaking world and that foreign cultures are mostly represented in topics such as racism and ethnicity. People from minority cultures also appear in a context, where they are presented as unique since they do not fit in the average stereotype image connected with their culture. Hence minorities come to symbolize “the other”. The exercises in the textbooks focus to some extent on reflection about culture and comparisons between different countries, and their habits. The majority of the texts focus on the Western world, that is the US and Great Britain either because of the geographical location of the texts or because of the author.

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