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Deep Exclusive π<sup>0</sup> Electroproduction Measured in Hall A at Jefferson Lab with the Upgraded CEBAFKarki, Bishnu 22 September 2020 (has links)
No description available.
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Professional development through community arts projects: a study of the influence of Thesele Creative Society on the career paths of five peopleMzaku, Thamsanqa 22 January 2014 (has links)
Thesis (M.A.)--University of the Witwatersrand, Faculty of Humanities, Arts and Culture Management, 2013 / This report examines the ways in which a community theatre project called Thesele Creative Society (TCS) active in Soweto, South Africa, influenced and broadened the career paths of five people who were directly marginalized by the Apartheid government’s policies. I focus on the period from 1991-1995, which corresponds to the transition to democracy, signifying increased accessibility within the country to a variety of career options for black people synchronous with an entry into a differently challenging global economy. In many parts of the world, community arts projects are known to enhance the ability of their participants to successfully participate in the job market and learn skills that are useful in life more generally. South African community arts projects are understood to have played a significant role in, inter alia, the economic and skills development of its participants over the last 60 years. Although located in a remote periphery of the arts, culture and heritage sector, with its impact running a risk of being undercounted within the creative economy, TCS proved to be one of the community arts projects with socio-economic bearing. Selected through purposive sampling, the five main participants of this study present intrinsically interesting cases through which I identify the types of skills provided by TCS within the community theatre environment, as well as the methodology employed in transferring these skills. I also show that the background and practice of TCS provides lessons in terms of the application of self-reliance and self-determination principles, and sequentially argue that the application of these principles is necessary for the advancement of many disadvantaged communities in South Africa. I create links between the qualitative data I have collected in the form of interviews with wider issues of creative economies, complementing existing theoretical and ideological studies of community arts practice with a practically grounded approach. This research draws attention to, and demonstrates the importance of, the study of community arts projects, as opposed to community arts centres, which have been the virtually exclusive focus of prior research.
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Development of Ready-to-Use Biosensors for Diagnostics and BiosensingJahanshahi-Anbuhi, Sana 06 1900 (has links)
Ideally, every person in the world should have access to a safe and clean water supply; if not all sources of water are clean and safe, at the very least, an effective method to detect water contamination should be readily available. An effective detection method should not only be sensitive, rapid, robust, and affordable, but, ideally, it should also be equipment-free and easy to transport and deliver to the end-users.
The main goal of this project is to develop a variety of bits and pieces of bioassay systems, with a particular focus on paper-based bioactive devices in order to provide portable and ready-to-use biosensors which can be useable by anyone anywhere around the world without requiring formal training.
According to the World Health Organization (WHO), 76,000 people each year die in India alone because of pesticide poisoning. Long term exposure to organophosphate pesticides is known to have adverse effects on neurological function and can lead to Alzheimer's Disease, Attention Deficit Hyperactivity Disorder (ADHD), and reduced Intelligence Quotient (IQ). The likelihood of long term exposure to pesticides is heightened in developing countries, so a reliable and inexpensive pesticide sensor is a much-needed device in the developing world. To address this need, this project reports on the development of a fully-automated bioactive paper-based sensor for the detection of organophosphate pesticides. In the proposed biosensor, two innovations were implemented to achieve a full-automated format for the pesticide sensor: (I) First is a PUMP ON A PAPER (Jahanshahi-Anbuhi et al., LOC, 2012) that increases the flow rate of fluids within paper-based microfluidic analytical devices and sequentially brings two separate liquid streams to the enzyme test zone on the paper sensor, and (II) the second innovation is a PIPETTE ON A PAPER (Jahanshahi-Anbuhi et al., LOC, 2014) that involved the creation of a pullulan (a natural non-ionic polysaccharide) temporary bridge-system to transfer a known amount of solution to the sensing zone that, gives the enzyme zone a chance to dry and accept the substrate solution from the slow channel after a fixed period of time. This proposed format results in a simplified assay that detects the presence of pesticides automatically without any further manipulation from the user.
However, the shelf life of this assay kit is challenging due to instability of both enzyme (AChE) and substrate (IDA) at room temperature. AChE loses its enzymatic activity when stored at room temperature and IDA becomes oxidized quickly. This problem is not unique to these two bio reagents, however; almost all bioassays which use bio-reagents (such as enzymes and small-molecular substrates) are unstable to varying degrees and require special shipping and storage. The instability of these molecules can arise from either thermal denaturation or chemical modification, such as oxidation or hydrolysis. Because of these issues, they often have to be shipped on dry ice with special packaging, which is costly. The cost of maintaining a cold chain for distributing bio-reagents accounts for up to 80% of the cost.
Aside from the cost, these reagents also have to be stored in bulk in refrigerators or freezers to minimize the loss of activity, but they must be thawed and aliquoted for their intended tests. Repeated freezing and thawing can result in a significant loss of activity, which often leads to less reliable test results. These issues make running such assays in resource-limited settings a significant challenge. There is, therefore, an urgent need for an assay system with stable reagents that is easy to use, simple to read, inexpensive, and that includes a method for the long-term stabilization of enzymes and other unstable reagents in pre-measured quantities.
To overcome to all these issues, pullulan is utilized for the development of pill-based-biosensors. Pullulan dissolves quickly in aqueous solutions and shows very high oxygen barrier properties in its film form. Considering the unique properties of pullulan, it is hypothesized that pullulan may be suitable for producing assay pills with encapsulated enzymes or other unstable molecules and may provide a simplified platform for carrying out bioassays in resource-limited settings. The application of these pill-based-biosensors is shown via the entrapment of AChE and IDA for the creation of an assay kit that can detect organophosphate pesticides (Jahanshahi-Anbuhi et al., Angew. Chem., 2014). Moreover, this thesis reports on the stabilization of highly unstable firefly luciferase for the detection of microorganisms and, more particularly, ATP. Through the use of pullulan, this thesis demonstrates that both the enzyme and the substrate can be protected, immobilized, and stabilized at room temperature, instead of the existing storage methods, which require temperatures <-20˚C. This innovation allows for a more convenient method of shipping the bioassay kits around the world without any extra care.
Furthermore, pullulan-based films are utilized for the development of a method for controlled multidirectional flow within paper-based biosensors. This method provides the possibility of trapping labile and volatile reagents and stabilizing them by forming thin films with pullulan. The trapped reagents within pullulan films can be strategically stacked and assembled on a paper strip in different directions. Furthermore, should the need arise, these reagents can be released and delivered sequentially or simultaneously in both vertical and lateral directions through the paper. The application of this method is shown for: (I) creation of "ready-to-use" assay kit for the detection of Escherichia coli (E. Coli). This assay kit has the step of cell lysing and proceeds automatically to the step in which enzymes react. The second application (II) shows the trapping of Simon’s reagents, which is widely used for methamphetamine detection.
Overall, these unique fabrication techniques can be widely used for the preparation of highly stable, ready-to-use, and user-friendly biosensors. We are currently working on the detection of other contaminants such as heavy metals, and we are starting on vaccine stabilization and delivery, which would have a tremendous impact for society. / Dissertation / Doctor of Engineering (DEng)
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Understanding the Responses of a Metal and a CMCTurbine Blade during a Controlled Rub Event using a Segmented ShroudLangenbrunner, Nisrene A. 08 August 2013 (has links)
No description available.
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DNA Origami Mechanisms and MachinesMarras, Alexander Edison 25 July 2013 (has links)
No description available.
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Design Of An Autopilot For Small Unmanned Aerial VehiclesChristiansen, Reed Siefert 23 June 2004 (has links) (PDF)
This thesis presents the design of an autopilot capable of flying small unmanned aerial vehicles with wingspans less then 21 inches. The autopilot is extremely small and lightweight allowing it to fit in aircraft of this size. The autopilot features an advanced, highly autonomous flight control system with auto-launch and auto-landing algorithms. These features allow the autopilot to be operated by a wide spectrum of skilled and unskilled users. Innovative control techniques implemented in software, coupled with light weight, robust, and inexpensive hardware components were used in the design of the autopilot.
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Particle Filter Based Mosaicking for Forest Fire TrackingBradley, Justin Mathew 16 July 2007 (has links) (PDF)
Using autonomous miniature air vehicles (MAVs) is a cost-effective, simple method for collecting data about the size, shape, and location characteristics of a forest fire. However, noise in measurements used to compute pose (location and attitude) of the on-board camera leads to significant errors in the processing of collected video data. Typical methods using MAVs to track fires attempt to find single geolocation estimates and filter that estimate with subsequent observations. While this is an effective method of resolving the noise to achieve a better geolocation estimate, it reduces a fire to a single point or small set of points. A georeferenced mosaic is a more effective method for presenting information about a fire to fire fighters. It provides a means of presenting size, shape, and geolocation information simultaneously. We describe a novel technique to account for uncertainty in pose estimation of the camera by converting it to the image domain. We also introduce a new concept, a Georeferenced Uncertainty Mosaic (GUM), in which we utilize a Sequential Monte Carlo method (a particle filter) to resolve that uncertainty and construct a georeferenced mosaic that simultaneously shows size, shape, geolocation, and uncertainty information about the fire.
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Thin Film Microfluidic and Nanofluidic DevicesHamblin, Mark Noble 09 August 2010 (has links) (PDF)
Lab-on-a-chip devices, also known as micro total analysis systems (μTAS), are implementations of chemical analysis systems on microchips. These systems can be fabricated using standard thin film processing techniques. Microfluidic and nanofluidic channels are fabricated in this work through sacrificial etching. Microchannels are fabricated utilizing cores made from AZ3330 and SU8 photoresist. Multi-channel electroosmotic (EO) pumps are evaluated and the accompanying channel zeta potentials are calculated. Capillary flow is studied as an effective filling mechanism for nanochannels. Experimental departure from the Washburn model is considered, where capillary flow rates lie within 10% to 70% of theoretical values. Nanochannels are fabricated utilizing cores made from aluminum, germanium, and chromium. Nanochannels are made with 5 μm thick top layers of oxide to prevent dynamic channel deformation. Nanochannel separation schemes are considered, including Ogston sieving, entropic trapping, reptation, electrostatic sieving, and immutable trapping. Immutable trapping is studied through dual-segment nanochannels that capture analytes that are too large to pass from one channel into a second, smaller channel. Polymer nanoparticles, Herpes simplex virus type 1 capsids, and hepatitis B virus capsids are trapped and detected. The signal-to-noise ratio of the fluorescently-detected signal is shown to be greater than 3 for all analyte concentrations considered.
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ARROW-Based On-Chip Alkali Vapor-Cell DevelopmentHulbert, John Frederick 22 May 2013 (has links) (PDF)
The author presents the successful development of an on-chip, monolithic, integrated rubidium vapor-cell. These vapor-cells integrate ridge waveguide techniques with hollow-core waveguiding technology known as Anti-Resonant Reflecting Optical Waveguides (ARROWs). These devices are manufactured on-site in BYU's Integrated Microelectronic Laboratory (IML) using common silicon wafer microfabrication techniques. The ARROW platform fabrication is outlined, but the bulk of the dissertation focuses on novel packaging techniques that allow for the successful introduction and sealing of rubidium vapor into these micro-sized vapor-cells. The unique geometries and materials utilized in the ARROW platform render common vapor-cell sealing techniques unusable. The development of three generations of successful vapor-cells is chronicled. The sealing techniques represented in these three generations of vapor-cells include high-temperature epoxy seals, cold-weld copper crimping, variable pressure vacuum capabilities, indium solder seals, and electroplated passivation coatings. The performance of these seals are quantified using accelerated lifetime tests combined with optical spectroscopy. Finally, the successful probing of the rubidium absorption spectrum, electromagnetically induced transparency, and slow light on the ARROW-based vapor-cell platform is reported.
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The Efficacy of Decoupled Search : The roles of commitment, assimilation, and ownership in external knowledge transference.Önnered, Simon January 2022 (has links)
Recent development in search for external knowledge links the practise with foresight and decouples the process from the actuating firm. Enabling new opportunities for generating insights whilst raising concerns for how change is inflicted on the focal firm. Through an action research study, the implementation of externally generated knowledge is examined whilst producing concepts for future business strategy and models. Complementing the study with a comparative project, using the focal firms own external innovation lab. Resulting in findings that shows how commitment affects the roles of foresight; assimilation steers levels of innovation; and ownership, the degree of utilization. Implications which inform the managing of the search interface between the firm and search agent; the effects of such ventures; and theoretical contributions regarding knowledge transference in decoupled foresight projects. Giving rise to a conceptual model of knowledge transference that explains the dynamics between the focal firm and decoupled agent which can help to evaluate the process and direct efforts to improve upon the value output. Showing that given enough commitment, assimilation, and ownership; findings can be anchored and produce tangible outcomes.
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