M.Pharm., Department of Pharmacy and Pharmacology, Faculty of Health Sciences, University of the Witwatersrand, 2011. / Ulcerative colitis (UC), notorious for its unpredictable attacks of inflammation of the large intestine, is estimated to affect as many as 1.4 million people in the USA and 2.2 million people in Europe with 15000-30000 new cases being diagnosed annually worldwide. The chronic inflammatory process is limited to various regions of the colonic mucosa and is postulated to occur due to a dysregulated mucosal response in the intestinal wall, facilitated by defects in the protective barrier function of the intestinal epithelium and mucosal immune system. Due to the range and extent of disease manifestations the goals of UC therapy are broad and non-specific. The focus of therapy is thus primarily placed on the treatment of active disease by ameliorating the signs and symptoms characteristic of the disease state with concurrent adjunctive and anti-inflammatory therapy. Thus, ideally a delivery system should facilitate a reduction in the pill burden, daily dosing requirements and allow for concurrent adjunctive and anti-inflammatory therapy with a single delivery system administration. Therefore, essentially the purpose of this work was to develop a novel stimuliresponsive oral tablet system (SROT) that provided targeted drug delivery of 5-ASA to the colon and loperamide HCl to the small intestine with a single delivery system. For this purpose, the employment of polymers that are termed ‘stimuli-responsive’ or ‘smart’ were established to be the most attractive approach for ‘activating’ drug release at the desired site in response to the pre-determined reliable stimulus. Thus, advantage is taken of the over 400 distinct species of anaerobic bacteria and their corresponding enzymatic activities in the colon. Investigations performed according to a Box-Behnken experimental design exposed an optimum enzyme-responsive colon-targeted tablet that effectively inhibited premature 5-ASA release in conditions simulating the upper gastrointestinal tract, whilst enabling an immediate initiation of drug release on exposure to colonic enzymes. The enzyme-responsiveness of the tablet was a direct result of the employment of only naturally-derived polysaccharides that were susceptible to colonic degradation. Furthermore, and more importantly, the prevention of premature drug release was achieved by the enzyme-responsive hydrophobic coating consisting of pectin and an aqueous ethycellulose dispersion that was applied to tablets until a ±10% total weight gain was achieved. In addition the in situ crosslinking between pectin and BaCl2 in the tablet matrix as well as the crosslinked 5-ASA-loaded granules resulted in a zero-order drug release throughout the 18 hour period in the simulated colonic environment containing enzymes. The development of the outer pepsin-responsive small intestinally-targeted coating was also conducted according to the Box-Behnken experimental design. Extensive investigations revealed an optimized pepsin-responsive coating after conducting the relevant studies on the 15 statisticallyderived formulations. Essentially, the tablets coated with the 40%w/v gelatine solutions resulted in the greatest increase in weight and shell thickness of the formulations however these were the least responsive to pepsin. The optimum pepsin-responsiveness was achieved from a gelatine coating of 14.379%w/v which was crosslinked for 6 hours in a glutaraldehyde-lactose dry mixture. Furthermore, the novel crosslinking method ensured that no entrapped loperamide HCl was prematurely lost during the crosslinking process. In addition, the optimum formulation also achieved 100% drug release in the small intestine-at its site of therapeutic action. In vivo investigations of the SROT in the large white pig model explicated the colon-targeting ability of the 5-ASA-loaded tablet as well as the benefits of the SROT compared to the conventional commercially available system, Asacol® (Aventis Pharma (Pty) Ltd.,Midrand, Johannesburg, South Africa). The success of the loperamide-loaded coating was evident from the minimal presence of loperamide HCl in plasma in the first 2 hours post-dosing compared to its commercially available counterpart Imodium® (Janssen Pharmaceutica (Pty) Ltd., Woodmead, Johannesburg, South Africa). Investigations into an alternate colon-targeted drug delivery system revealed 3 novel composite polyacrylamide-polysaccharide hydrolyzed electrolytic matrices consisting of either pectin, chitosan or a combination of both, complexed with hydrolyzed polyacrylamide. Each matrix presented with varying surface area and porositometric properties which influenced their drug release behaviour. These formulations hold potential for numerous controlled drug delivery applications and are not exclusively limited to colon-targeting.

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Reliable authorization and authentication is now becoming necessary for many everyday activities such as boarding an aircraft, doing financial transactions etc. This work deals with the possibility of proposing an appropriate method of acquisition, processing and evaluation of data from the tablet itself, focusing on the possibility of obtaining data from the graphics tablet used in conjunction with a personal computer, for the purpose of verifying identity. It contains an overview of biometrics, as independent developing science over the last decades of the 20th century to the present, a summary of the development of a graphics tablet, the current situation, a brief overview of the most popular technologies used in their construction and distribution. Furthermore, it focuses on the design and implementation of appropriate procedures to obtain data provided by the Trust tablet TB - 7300, using available software development kit for the Microsoft Tablet PC, and a comparison of WinForms and WPF model (.NET Framework), with the declaration of suitability for the use of the second one. Last but not least, according to the response from the available set of users, this work focuses on the design of appropriate types of input data, test patterns, method and application for collecting and processing data from the graphic tablet, as well as their use for the verification of the identity of the individual. Ultimately, it is possible to discuss the accuracy of the method on a set of users, its suitability for use and shortcomings. Based on the analysis of the issue, the proposed method can be declared as under-optimal - it is safe, but inaccurate with low stability and repeatability. It is also important to accent that this is just the initial proposal, the use of applications in everyday life is for current phase impossible and the transition from laboratory conditions would require further development and improvement of the process.

Tese de mestrado integrado. Engenharia em Multimédia. Faculdade de Engenharia. Universidade do Porto. 2010

The inferred mode protocol uses contextual reasoning and local mediators to eliminate the need to access specic modes to perform draw, select, move and delete operations in a sketch interface. This thesis describe an observational experiment to understand the learn- ability, user preference and frequency of use of mode inferencing in a sketch appli- cation. Novel methodology is presented to study both quantitative and long term qualitative facets of mode inferencing. The experiment demonstrated that participants instructed in the in- terface features enjoyed fluid transitions between modes. As well, interaction techniques were not self-revealing: Participants who were not instructed in interaction techniques took longer to learn about inferred mode features and were more negative about the interaction techniques. Over multiple sketching sessions, as users develop expertise with the system, they combine inferred mode techniques to speed interaction, and frequently make use of scratch space on the display to retrain themselves and to tune their behaviors. Lastly, post- task interviews outline impediments to discoverability and how performance is affected by negative perceptions around computational intelligence. The results of this work inform the design of sketch interface techniques that incorporate noncommand features.

The intention is to focus on the implementation of the tablet in preschools and how the intentions around the introduction of the tablet take shape in different preschools. The method is semi structured interviews where the respondents consist of 3 preschool directors and 6 teachers where the preschool directors work. This is a relevant subject to illustrate, as the tablet has become a tool in preschool where it seems to be different opinions about how it should be used. This study aims to understand how the implementation can take form in different preschools, what kind of similarities and differences we can see with the intentions of the tablet and if there is need of clarification on the workings of the tablets in preschools. The results show that the intentions around the introduction of the tablet in preschool look different in the preschools, and the implementation of this new technology starts in a small scale with help of photographing and videotaping. In addition to this, there is no specific thought on how the tablets should be implemented in preschool. / Avsikten är att fokusera på implementeringen utav surfplattan i förskoleverksamheten och hur intentionen kring införandet utav surfplattan ser ut på olika förskolor. Metoden är semistrukturerade intervjuer där respondenterna består utav 3 förskolechefer och 6 pedagoger där respektive förskolechef verkar. Detta är ett relevant ämne att belysa, då surfplattan har blivit ett verktyg i förskolan som det verkar finnas olika uppfattningar om vad och hur den skall användas till. Därigenom syftar denna undersökning till att se hur implementeringen utav surfplattan kan se ut på olika förskolor, vad för likheter och olikheter kan vi se med intentionen utav surfplattan och om finns det behov av tydliggörande utav arbetet kring surfplattorna i verksamheten. Resultatet visar på att intentionerna kring införandet utav surfplattor i verksamheten ser olika ut på de representerade förskolorna, samt att implementeringen utav denna nya teknik påbörjas i liten skala med hjälp utav fotografering och filmning. Utöver detta har inga specifika tankar funnits kring hur surfplattorna ska implementeras i verksamheten.

The inferred mode protocol uses contextual reasoning and local mediators to eliminate the need to access specic modes to perform draw, select, move and delete operations in a sketch interface. This thesis describe an observational experiment to understand the learn- ability, user preference and frequency of use of mode inferencing in a sketch appli- cation. Novel methodology is presented to study both quantitative and long term qualitative facets of mode inferencing. The experiment demonstrated that participants instructed in the in- terface features enjoyed fluid transitions between modes. As well, interaction techniques were not self-revealing: Participants who were not instructed in interaction techniques took longer to learn about inferred mode features and were more negative about the interaction techniques. Over multiple sketching sessions, as users develop expertise with the system, they combine inferred mode techniques to speed interaction, and frequently make use of scratch space on the display to retrain themselves and to tune their behaviors. Lastly, post- task interviews outline impediments to discoverability and how performance is affected by negative perceptions around computational intelligence. The results of this work inform the design of sketch interface techniques that incorporate noncommand features.

Since the beginning of the 21st century, the world has seen a changing trend in computing power thanks to advancements in technology. One peculiar platform in the field of usability is the tablet. Due to its recent introduction, it has had a relatively short life span with few established methodologies. The tablet is gaining market share at a tremendous speed and thus there has been a big demand of the appropriate evaluation methods. This comprehensive study intention is to; through a literature survey and transformation of collected material identify what usability requisites there are when developing a user interface for a tablet application. Existing user interface guidelines from various companies involving the development of tablet software are examined and paired up with usability principles in the creation of the usability checklist. The usability checklist practical effectiveness is tested on various tablet applications and the results are compared to the results of a usability user test  valuation. The majority of the usability problems found by the user test evaluation are codiscovered, in addition, there were a greater number of undiscovered usability problems that was identified with the checklist evaluation.