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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.
161

A study of trial participants' understanding and attitudes towards randomisation, double-blinding and placebo use, and a pilot intervention in a microbicide trial in Malawi.

Ndebele, Paul Maduba. January 2010 (has links)
This empirical study was aimed at assessing trial participants’ understanding of randomisation, double blinding and placebo use as well as investigating their attitudes towards the three procedures. The study was conducted within the HPTN035 microbicide trial that was being conducted in Blantyre and Lilongwe in Malawi among other sites. The study was descriptive in nature and used a combination of qualitative and quantitative methods which included review of study documents, in-depth interviews with study staff, structured interviews with a sample of 203 participants and two focus group discussions with 18 microbicide trial participants. Overall, more than half of participants were categorised as having lower levels of understanding on the concepts under study. The study also established that the majority of participants had negative attitudes towards the three procedures. Based on these findings, a pilot intervention was designed aimed at improving understanding. The pilot intervention consisted of an information session which was delivered with the assistance of a PowerPoint. During the session, the three terms were explained using a story based on the growing of crops, as Malawi is an agricultural society. The intervention phase was delivered using a sample of 36 low scorers who were randomly assigned to the intervention and non-intervention arms. An assessment after the intervention suggested that the intervention was useful in improving understanding of the three procedures. The findings provide some evidence that research participants can understand research procedures if the procedures are explained in user-friendly terms and if information concerning their justification and personal implications is provided. The findings further suggest that the intervention was useful in changing participants’ attitudes towards randomisation and double blinding. The intervention did not change attitudes towards placebo use in a statistically significant way. Theoretical and practical recommendations, as well as suggestions for further research were recommended. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.
162

AND ... AND ... AND ... : Reiterating Financial Derivation

Bay, Thomas January 1998 (has links)
This essay is an attempt at examining the general logic of derivation, the organisational geno-practice of financial derivationówhat I have called: reiterative derivation. I will endeavour to reiterate, to repeat otherwise, to displace the derivative distinction which apart from providing the financial markets with ever new business opportunities, makes financial instruments like options and futures the potential turning point, the crisis, the utmost risk, the pure possibility, of any economic reality. Stated another way, reiterative derivation is the opening of economy, the economyís way out, its line of flight, its passibility, the invention of its future. A derivative is a financial strategy designed to handle price risks, value fluctuations in its underlying economy; it performs this task by acting simultaneously as either an instrument or a marketable commodity. Offering itself not only as a forceful appendage, a financial device, but as the possibility to deterritorialise displace unsecure uproot its underlying economic reality, the derivative displays an extremely creative approach to the economic world. What I would like to indicate in and through the present essay, then, is how financial derivation works. Not so much, perhaps, in the instrumental sense, but rather as a vehicle allowing one to create and travel into economic worlds, or, perhaps better, economic assemblages, economic ensembles so complex and complicated that they can no longer be understood as either this or that, either, for instance, real or imaginary, but should rather be interstood as imaginary economic realities, either or ... or ... or ... both and ... and ... and ... Abstract, as I use it here, should not be understood in its (perhaps) most common or ordinary sense, as a summary or epitome, as something that presents the point, comprises or concentrates the essence of my essay and thereby facilitates its comprehension. It should rather be interstood as, at one and the same time, a deviation, a diversion, an attempt to draw your attention away from the textual strategies employed (the word abstract derives from the Latin verb abstrahere, to draw away, withdraw); to ìguideî your reading, that is to say, to lure you into the textís own protocols of reading, sheltering thereby the text from being conceived too generously, a way of inviting you to invent your own reading, to write while reading, to proceed with a Deleuzean restrained step, to decide without choosing, to hold while letting go, to grasp while leaving be, to open yourself up to what is still to come, to not knowing what will happen before it happens, to the possibility of nothing happening, towards that which is (always) in the process of coming about, to adventure, the future, to the theme of this essay: the experience of financial derivation, the geno-practice of financial derivation, the economyís monstrous other, the economic futureóto, in short: reiterative derivation.
163

New Directions in Catalyst Design and Interrogation: Applications in Dinitrogen Activation and Olefin Metathesis

Blacquiere, Johanna M. 09 May 2011 (has links)
A major driving force for development of new catalyst systems is the need for more efficient synthesis of chemical compounds essential to modern life. Catalysts having superior performance offer significant environmental and economic advantages, but their discovery is not trivial. Well-defined, homogeneous catalysts can offer unparalleled understanding of ligand effects, which proves invaluable in directing redesign strategies. This thesis work focuses on the design of ruthenium complexes for applications in dinitrogen activation and olefin metathesis. The complexes developed create new directions in small-molecule activation and asymmetric catalysis by late-metal complexes. Also examined are the dual challenges, ubiquitous in catalysis, of adequate interrogation of catalyst structure and performance. Insight into both is essential to enable correlation of ligand properties with catalyst activity and/or selectivity. Improved methods for accelerated assessment of catalyst performance are described, which expand high-throughput catalyst screening to encompass parallel acquisition of kinetic data. A final aspect focuses on direct examination of metal complexes, both as isolated species, and under catalytic conditions. Applications of charge-transfer MALDI mass spectrometry to structural elucidation in organometallic chemistry is described, and the technique is employed to gain insight into catalyst decomposition pathways under operating conditions.
164

Development Of A Tool For Web Based Control Engineering Education

Cigeroglu, Huseyin 01 August 2004 (has links) (PDF)
It is obvious that learning is more productive with visual mediums and simulations. Especially in technical subjects, this approach is more important. Visual modification of parameters in a control system provides many benefits both in analyzing the system and in learning process. Additionally if this material is published on the internet, students can reach anywhere anytime to this material. This thesis describes a Web-based system developed for control engineering education for both the instructor and the student. The system will generate learning material according to the instructor&rsquo / s requests. Instructors will design the system and define the borders to help students to learn rapidly the subject of the lesson. They will decide on the functions and which variables can be played with and present them to the students. This work will help the students that take the basic courses of control engineering. Students will interactively experiment with the system. They will see the effect by changing the variables via sliders of certain functions (e.g. step, bode, root locus...). The system is developed with the programming language JAVA to run over the internet and to be platform independent.
165

An examination of emotion-based strategies in ’altruistic’ mobilisation: a case study of the animal rights movement.

Grivas, Rebecca January 2008 (has links)
This thesis examines the emotion-based strategies employed by activists for the purpose of persuading individuals to participate directly in social movements. In particular, the emphasis is placed on getting people involved in ‘altruistic’ mobilisation; a descriptive utilised in order to distinguish these movements from previous research done in which a tangible material gain is presented as an inducement for participation. The thesis investigates the animal rights movement as it pertains to the issue of animal vivisection, and endeavours to identify the linguistic strategies employed by these activists with the goal of understanding how to facilitate ‘altruistic’ movements more generally. A textual analysis, which was consistent with Halliday’s (2004) systemic functional linguistics, was conducted on mobilisation pamphlets written by groups seeking support for either animal vivisection or animal rights. To this end, the analysis considered both the original movement (i.e. the anti-vivisection movement) and the counter-movement (i.e. the pro-research movement). The analysis considers the linguistic and visual strategies used by movement organisers in placing a moral onus on the reader to support the movement. From this analysis it is argued that the success of the animal rights movement stems from its ability to present graphic visual imagery that supplies evidential support for the claims being made in text. In addition, the animal rights texts have been able to frame the issue of animal vivisection in terms of emotional appeals designed to elicit feelings of moral outrage in the reader. It is posited that the animal rights movement has been able to effectively combine images and emotion-based linguistic strategies in order to facilitate the consideration of the issue in terms of an ‘ethical identity’ that helps generate moral outrage in the reader and thereby encouraging participation in the movement. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1339773 / Thesis (Ph.D.) - University of Adelaide, School of Psychology and School of Humanities, 2008
166

Evolving spiking neural networks for adaptive audiovisual pattern recognition

Wysoski, Simei Gomes Unknown Date (has links)
This dissertation presents new modular and integrative information methods and systems inspired by the way the brain performs information processing, in particular, pattern recognition. The proposed artificial systems use spiking neurons as basic elements, which are the key components of spiking neural networks. Of particular interest to this research are various spiking neural network architectures and learning procedures that permit different pattern recognition problems to be solved in an evolvable and adaptive way. Spiking neural networks are used to model human visual and auditory pathways and are trained to perform the specific task of person authentication. The systems are individually tuned and trained to recognize facial information and to analyze sound signals from spoken sentences. The modelling of the integration of different sources of information (multisensory integration) using spiking neural networks is also a subject of investigation. A network architecture is proposed and a model for audiovisual pattern recognition is designed as an example. The main original contributions of this thesis are: a) Evaluation and further extension of adaptive learning procedures to perform visual pattern recognition. A new learning procedure that enables the system to change its structure, creating/merging neuronal maps of spiking neurons is presented and evaluated on a face recognition problem. b) Design of two new spiking neural network architectures to perform person authentication through the processing of speech signals. c) Design and evaluation of a new architecture that integrates sensory modalities based on spiking neurons. The integrative architecture combines opinions from individual modalities within a supramodal layer, which contains neurons sensitive to multiple sensory information. An additional feature that increases biological relevance is the crossmodal coupling of modalities, which effectively enables a given sensory modality to exert direct influence upon the processing areas typically related to other modalities. The contributions were published in one journal paper and in four refereed international conference proceedings. The proposed system designs were implemented and, through computer simulations, demonstrated comparable performance with traditional benchmarking methods. The systems have some promising features: they can be naturally optimized in respect to different criteria: accuracy (when very accurate results are expected), energy efficiency (when management of resources play an important role), and speed (when a decision needs to be made within a limited time). In this thesis, most of the parameters have been exhaustively optimized by hand or by using simple heuristics. As a direction for future work, there is an opportunity to include automated, specially tailored parameters optimization procedures or even general-purpose optimization algorithms, e.g., Genetic Algorithms and Particle Swarm Optimization. Overall, the results obtained in this thesis clearly indicate that it is indeed possible to have fast and accurate adaptive pattern recognition systems scalable for multiple modalities computing with simple models of spiking neurons. However, it is important to advance the theory of spiking neurons to take advantage of its biological relevance to reach similar or better performance when compared to the human brain, for instance, exploring new neuron models, information coding schemes and network connectivity.
167

Psychedelic psychiatry: LSD and post-World War II medical experimentation in Canada /

Dyck, Erika. Wright, David, January 2005 (has links)
Thesis (Ph.D.)--McMaster University, 2005. / Supervisor: David Wright. Includes bibliographical references (leaves 272-306). Also available online.
168

Cadmium in newborns : bioavailability from infant food studied in a rat pup, a piglet and a human intestinal cell line model /

Eklund, Gunilla, January 2003 (has links) (PDF)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.
169

On soil behaviour during field traffic /

Trautner, Andreas , January 2003 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.
170

Metabolism of soluble proteins by rumen microorganisms and the influence of condensed tannins on nitrogen solubility and degradation /

Hedqvist, Helena, January 2004 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2004. / Härtill 4 uppsatser.

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