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Doctor of Philosophy / Department of Chemistry / Christopher T. Culbertson / As the field of separation science evolves so do the techniques, tools and capabilities of the discipline. The introduction of microfluidics stemmed from a desire to perform traditional analyses faster and on a much smaller scale. The small device sizes exploited in microfluidics permits the investigation of very small volumes of very dilute samples yielding information inaccessible by traditional macroscale techniques. All of the chapters presented in this dissertation illustrate attempts to supplement current microscale techniques with new tools, techniques and analysis schemes for looking at biologically relevant analyses. In chapter two I present the development and characterization of an amphiphilic polymer that has potential as a material for the fabrication of microfluidic devices. This material is composed of a poly(dimethylsiloxane)-poly(ethylene oxide) block copolymer and is dramatically more hydrophilic than the other polymeric materials currently used for the fabrication of microfluidic templates, mainly poly(dimethylsiloxane). Biomolecules such as proteins are notoriously hydrophobic and will tend to adsorb to other hydrophobic surfaces thus the use of a hydrophilic material may serve to reduce or eliminate this problem. The amphiphilic material is of a suitable durability for micromolding and molded channel architectures can be sealed between two layers of the material by simple conformal contact permitting the execution of high speed electrophoretic separations. Chapter three contains initial results obtained while investigating the fluorescent labeling and electrophoretic separation of ecdysteroids. Ecdysteroids are hormones found in insects that are responsible for controlling the process of molting. Here we attempted to analyze these molecules by employing a reactive fluorescent probe, BODIPY FL® hydrazide, that would target the α,β-unsaturated ketone group on the steroid, permitting its analysis by capillary electrophoresis with laser induced fluorescence detection. While optimistic initial results were obtained with the labeling and analysis of similar functional groups on model compounds such as progesterone, labeling of the ecdysteroid molecules was never achieved to a degree that would permit reliable analysis. In chapter four I report the development and use of a microimmunoaffinity column for the analysis of insect serine protease inhibitors, or serpins. These proteins play a very important role in the regulation of insect immune responses and their activity may play an integral role in the effective transmission of the malaria parasite by the mosquito Anopheles gambiae. A microimmunoaffinity column was constructed from magnets, poly(dimethylsiloxane), fused silica capillary and Protein A coated magnetic microspheres. In these initial studies, purified antibodies to serpin protein, as well as purified serpin protein, were used to prepare and investigate the ability to isolate, preconcentrate, and elute serpin proteins for subsequent analysis. By implementing this miniaturized system which incorporates very small fluid volumes we hoped to extend this technique to the analysis of very small samples, and eventually to the analysis of individual small insects. Our work indicates that it is possible to isolate, elute, and detect serpin protein on a traditional western blot membrane. Chapter five presents the development of a novel polymer blend for the fabrication of paper-based microfluidic devices and use of these devices in the performance of diagnostically relevant clinical assays. We took the concept of paper-based microfluidic devices and improved upon the current photoactive polymers used for their fabrication by developing a polymer blend using an acryloxy modified siloxane polymer as well as a commercially available photoactive adhesive, Norland Optical Adhesive 74. This blended polymer resulted in a dramatic reduction in fabrication time as well as improved resolution permitting the reliable patterning of small feature sizes. We also report for the first time a demonstration of these devices performing a two-step spatially separated online chemical derivatization facilitating the analysis of urinary ketones. These devices are predominantly used for the analysis of urine, and their application was extended to the quantitation of nitrite in saliva for the purposes of hemodialysis monitoring. While varied in application, all of the data presented in this dissertation exploits the power of miniaturization to improve current methods of analysis and to extend macroscale techniques to trace biological analytes.

Technologists predict that electronic information dissemination will create a paperless work environment. In spite of such predictions, paper-based internal communication will remain the primary medium for disseminating information in organizations for decades to come. However, electronic technology will have an impact on paper information production that may be more profound than changes following word processing's introduction. Previously unavailable for everyday production to enhance word meaning, certain graphic techniques now can be used to access readers' preconditioned symbol meanings to increase comprehension of routine correspondence and information internalization. This quasi-experimental field study examines interactions among laser-printer graphic treatment and communication variables as contributors to explaining variance in comprehension. Set Multiple Regression/Correlation analysis identifies significant variance explained by conditional relationships between near-typeset quality text and readers' self-interest and between near-typeset quality text and text's readability. The conditional relationship of near-typeset quality and self-interest shows increase in reader comprehension at a greater rate than the comprehension increase rate attributed to the reader's self-interest increase alone. This suggests that conditional relationships may be accessing an internal judgment process interpreting greater self-interest in near-typeset printed text. The conditional relationship between near-typeset quality and readability reveals that at more difficult reading levels comprehension is greater for near-typeset text. The significance of this relationship indicates that an internal judgment process is involved rather than the difference being attributed to legibility treatment. The strength of these conditional relationships suggests that planning for communication policies and practices should be a part of organizational strategic planning in the same ways as are financial analysis, operations planning, or human resource management.

<p>Military work-practice is a difficult area of research where paper-based approaches are still extended. This thesis proposes a solution which permits the digitalization of information at the same time as workpractice remains unaltered for soldiers working with maps in the field. For this purpose, a mobile interactive paper-based platform has been developed which permits the users to maintain their current work-flow. The premise of the solution parts from a system consisting of a prepared paper-map, a cellular phone, a desktop computer, and a digital pen with bluetooth connection. The underlying idea is to permit soldiers to take advantage of the information a computerized system can offer, at the same time as the overhead it incurs is minimized. On one hand this implies that the solution must be light-weight, on the other it must retain current working procedures as far as possible. The desktop computer is used to develop new paper-driven applications through the application provided in the development framework, thus allowing the tailoring of applications to the changing needs of military operations. One major component in the application suite is a symbol recognizer which is capable of recognizing symbols parting from a template which can be created in one of the applications. This component permits the digitalization of information in the battlefield by drawing on the paper-map. The proposed solution has been found to be viable, but still there is a need for further development. Furthermore, there is a need to adapt the existing hardware to the requirements of the military to make it usable in a real-world situation.</p>

<p>This paper analyzes the two test forms used by TOEFL: IBT and PBT. The analysiswill focus on the reading comprehension section, its design features, content, andscoring results. The aim is to assess the reliability of the two test forms as well as toidentify factors influencing candidate performance in the reading comprehension test.Three factors are identified: test setting, test difficulty and scoring methods and results.The latter two will be focused on because test difficulty consistency directly decides thetest result consistency. And as the goal of the candidate is to achieve as high a score aspossible, and success is measured in terms of numbers, score reliability is a primaryconcern for both candidate and examining body alike.</p>

The transition to digital TV is changing the television set into an entertainment as well as information supplier device that provides two-way communication with the viewer. However, the present remote control device is not appropriate for navigation through the huge amount of services and information provided by the future digital TV, presumably also a device for accessing the Internet. One possibility for coping with the complex information navigation required by TV viewers is an augmentation of the interaction tools currently available for TV. Two approaches to such an augmentation are investigated in this thesis: linking paper-based TV guides to the digital TV and enhancing the remote control unit with speech interaction. Augmentation of paper-based TV guides is a futuristic research approach based on the integration of paper-based TV guides into computation technology. This solution provides interactive paper-based TV guides that also function as a remote control for the TV. A prototype system is developed and explorative studies are conducted to investigate this approach. These studies indicate the benefits of integrating paper-based TV guides into the TV set. They also illuminate the potential to provide innovative solutions for home information systems. Integrating familiar physical artefacts, such as paper and pen into TV technology may provide easy access to information services usually provided by PCs and the Internet. Thus, the same augmentation needed for TV as an entertainment device also opens up new communication channels for providing society information to citizens who do not feel comfortable with conventional computers. The thesis also reports on studies of speech interfaces for TV information navigation. Traditional speech interfaces have several common problems, such as user acceptance and misinterpretation of user input. These problems are investigated in empirical and explorative studies with implementation of mockups and running research systems. We have found that the pragmatic solution of augmenting remote control devices by speech is a suitable solution that eases information navigation and search. / On the day of the public defence the status of articles III and V was: Submitted.

Books and printed materials have been used as a major learning content for thousands of years. Nowadays, Smartphone is considered as an important tool for mobile learning. This study designed a learning environment with paper and Smartphone which seamlessly integrates printed materials and digital materials. The idea is to augment the traditional paper-based materials with plenty of digital materials available on the Internet. Furthermore, because both book and Smartphone are with very good mobility, the designed system is also very suitable for mobile learning. Two special mechanisms were designed for supporting learning activities, and their effects on learning performance were evaluated. The first one is learning recommendation which is generated based on the learning portfolio. The second one is automated content connection which can reduce the loading of context switching between printed materials and digital materials so as learners can be more concentrated on learning tasks. A system was designed and implemented for conducting an experiment and data collection. The statistic analysis shows that learning recommendation has a significant positive effect on learning performance; however, the effect of automated content connection on learning performance is not significant. Besides, the questionnaire survey also shows that learners have positive attitude toward the acceptance of the learning system designed in this study. Based on the results, some implications and suggestions are provided for researchers and instructors.

Reading from paper-based materials has been a major way for people to acquire knowledge. However, paper-based materials are constricted in presenting abstract and complex knowledge or concepts. Recent development of smartphone makes it a device not only for interpersonal communication, but also for accessing rich digital resources over the Internet. Because both paper-based materials and smartphone are mobile and portable, we can make use of the networking capability of smartphone to access digital materials from the Internet to enrich conventional paper-based reading activities such that students¡¦ reading comprehension can be enhanced. The present study came up with an innovative paper-based reading system integrated with digital materials delivered from the smartphone. QR codes were employed to automatically link the content of the print material with relevant digital resources. Also, questions were given to students along the reading process to scaffold the reading activity in order to help students comprehend the essence of the reading pieces. A quasi-experimental design was used to evaluate the effectiveness of the learning system in improving students¡¦ reading comprehension. The results suggested that whether or not using QR code to automate linking digital and print materials does not significantly influence student reading comprehension; however, using questions to scaffold the reading process significantly improves students¡¦ reading comprehension. The survey conducted in the experiment suggested that most of the students agreed that the integrated learning system benefits English reading comprehension. The implication of the results and suggestions to system design and future studies were then addressed.

This thesis focuses on the development of two new applications using ion concentration polarization (ICP): an out-of-plane microfluidic approach for water desalination and a method for concentration and transportation of charged analytes in paper-based biomedical diagnostic device. In the first work, we present an out-of-plane desalination approach using ICP. A depletion boundary separates salt ions and purified water into distinct vertically stacked layers. The out-of-plane design enables multiplexing in three dimensions, providing the functional density required for practical applications. The second work demonstrates an active control mechanism of target analytes in paper using ICP. Both external devices (with all functional units on one side of paper) and integrated paper microfluidic devices (by embedding all functional units in paper) were developed to concentrate and transport charged analyte molecules in the paper. We also demonstrate a new fabrication method of nanofluidic and hydrophobic barriers (nanoporous membrane patterning) in paper microfluidic device.

This thesis focuses on the development of two new applications using ion concentration polarization (ICP): an out-of-plane microfluidic approach for water desalination and a method for concentration and transportation of charged analytes in paper-based biomedical diagnostic device. In the first work, we present an out-of-plane desalination approach using ICP. A depletion boundary separates salt ions and purified water into distinct vertically stacked layers. The out-of-plane design enables multiplexing in three dimensions, providing the functional density required for practical applications. The second work demonstrates an active control mechanism of target analytes in paper using ICP. Both external devices (with all functional units on one side of paper) and integrated paper microfluidic devices (by embedding all functional units in paper) were developed to concentrate and transport charged analyte molecules in the paper. We also demonstrate a new fabrication method of nanofluidic and hydrophobic barriers (nanoporous membrane patterning) in paper microfluidic device.