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Demand for biosensor research applications is growing steadily. According to a new report by Frost & Sullivan, the biosensor market is expected to reach $14.42 billion by 2016. Clinical diagnostic applications continue to be the largest market for biosensors, and this demand is likely to continue through 2016 and beyond.

Demand for biosensor research applications is growing steadily. According to a new report by Frost & Sullivan, the biosensor market is expected to reach $14.42 billion by 2016. Clinical diagnostic applications continue to be the largest market for biosensors, and this demand is likely to continue through 2016 and beyond. Biosensor technology for use in clinical diagnostics, however, requires translational research that moves bench science and theoretical knowledge toward marketable products. Despite the high volume of academic research to date, only a handful of biomedical devices have become viable commercial applications. Academic research must increase its focus on practical uses for biosensors. This dissertation is an example of this increased focus, and discusses work to advance microfluidic-based protein biosensor technologies for practical use in clinical diagnostics. Four areas of work are discussed: The first involved work to develop reusable/reconfigurable biosensors that are useful in applications like biochemical science and analytical chemistry that require detailed sensor calibration. This work resulted in a prototype sensor and an in-situ electrochemical surface regeneration technique that can be used to produce microfluidic-based reusable biosensors. The second area of work looked at non-specific adsorption (NSA) of biomolecules, which is a persistent challenge in conventional microfluidic biosensors. The results of this work produced design methods that reduce the NSA. The third area of work involved a novel microfluidic sensing platform that was designed to detect target biomarkers using competitive protein adsorption. This technique uses physical adsorption of proteins to a surface rather than complex and time-consuming immobilization procedures. This method enabled us to selectively detect a thyroid cancer biomarker, thyroglobulin, in a controlled-proteins cocktail and a cardiovascular biomarker, fibrinogen, in undiluted human serum. The fourth area of work involved expanding the technique to produce a unique protein identification method; Pattern-recognition. A sample mixture of proteins generates a distinctive composite pattern upon interaction with a sensing platform consisting of multiple surfaces whereby each surface consists of a distinct type of protein pre-adsorbed on the surface. The utility of the "pattern-recognition" sensing mechanism was then verified via recognition of a particular biomarker, C-reactive protein, in the cocktail sample mixture.
ContributorsChoi, Seokheun (Author) / Chae, Junseok (Thesis advisor) / Tao, Nongjian (Committee member) / Yu, Hongyu (Committee member) / Forzani, Erica (Committee member) / Arizona State University (Publisher)
Created2011
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Description
A wireless hybrid device for detecting volatile organic compounds (VOCs) has been developed. The device combines a highly selective and sensitive tuning-fork based detector with a pre-concentrator and a separation column. The selectivity and sensitivity of the tuning-fork based detector is optimized for discrimination and quantification of benzene, toluene, ethylbenzene,

A wireless hybrid device for detecting volatile organic compounds (VOCs) has been developed. The device combines a highly selective and sensitive tuning-fork based detector with a pre-concentrator and a separation column. The selectivity and sensitivity of the tuning-fork based detector is optimized for discrimination and quantification of benzene, toluene, ethylbenzene, and xylenes (BTEX) via a homemade molecular imprinted polymer, and a specific detection and control circuit. The device is a wireless, portable, battery-powered, and cell-phone operated device. The device has been calibrated and validated in the laboratory and using selected ion flow tube mass spectrometry (SFIT-MS). The capability and robustness are also demonstrated in some field tests. It provides rapid and reliable detection of BTEX in real samples, including challenging high concentrations of interferents, and it is suitable for occupational, environmental health and epidemiological applications.
ContributorsChen, Zheng (Author) / Tao, Nongjian (Thesis advisor) / Chae, Junseok (Committee member) / Forzani, Erica (Committee member) / Arizona State University (Publisher)
Created2011
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Description
This thesis describes several approaches to next generation DNA sequencing via tunneling current method based on a Scanning Tunneling Microscope system. In chapters 5 and 6, preliminary results have shown that DNA bases could be identified by their characteristic tunneling signals. Measurements taken in aqueous buffered solution showed that single

This thesis describes several approaches to next generation DNA sequencing via tunneling current method based on a Scanning Tunneling Microscope system. In chapters 5 and 6, preliminary results have shown that DNA bases could be identified by their characteristic tunneling signals. Measurements taken in aqueous buffered solution showed that single base resolution could be achieved with economic setups. In chapter 7, it is illustrated that some ongoing measurements are indicating the sequence readout by making linear scan on a piece of short DNA oligomer. However, to overcome the difficulties of controlling DNA especially ssDNA movement, it is much better to have the tunneling measurement incorporated onto a robust nanopore device to realize sequential reading of the DNA sequence while it is being translocated.
ContributorsHuang, Shuo (Author) / Lindsay, Stuart (Thesis advisor) / Sankey, Otto (Committee member) / Tao, Nongjian (Committee member) / Drucker, Jeff (Committee member) / Ros, Robert (Committee member) / Arizona State University (Publisher)
Created2011
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Description
Dual-wavelength laser sources have various existing and potential applications in wavelength division multiplexing, differential techniques in spectroscopy for chemical sensing, multiple-wavelength interferometry, terahertz-wave generation, microelectromechanical systems, and microfluidic lab-on-chip systems. In the drive for ever smaller and increasingly mobile electronic devices, dual-wavelength coherent light output from a single semiconductor laser

Dual-wavelength laser sources have various existing and potential applications in wavelength division multiplexing, differential techniques in spectroscopy for chemical sensing, multiple-wavelength interferometry, terahertz-wave generation, microelectromechanical systems, and microfluidic lab-on-chip systems. In the drive for ever smaller and increasingly mobile electronic devices, dual-wavelength coherent light output from a single semiconductor laser diode would enable further advances and deployment of these technologies. The output of conventional laser diodes is however limited to a single wavelength band with a few subsequent lasing modes depending on the device design. This thesis investigates a novel semiconductor laser device design with a single cavity waveguide capable of dual-wavelength laser output with large spectral separation. The novel dual-wavelength semiconductor laser diode uses two shorter- and longer-wavelength active regions that have separate electron and hole quasi-Fermi energy levels and carrier distributions. The shorter-wavelength active region is based on electrical injection as in conventional laser diodes, and the longer-wavelength active region is then pumped optically by the internal optical field of the shorter-wavelength laser mode, resulting in stable dual-wavelength laser emission at two different wavelengths quite far apart. Different designs of the device are studied using a theoretical model developed in this work to describe the internal optical pumping scheme. The carrier transport and separation of the quasi-Fermi distributions are then modeled using a software package that solves Poisson's equation and the continuity equations to simulate semiconductor devices. Three different designs are grown using molecular beam epitaxy, and broad-area-contact laser diodes are processed using conventional methods. The modeling and experimental results of the first generation design indicate that the optical confinement factor of the longer-wavelength active region is a critical element in realizing dual-wavelength laser output. The modeling predicts lower laser thresholds for the second and third generation designs; however, the experimental results of the second and third generation devices confirm challenges related to the epitaxial growth of the structures in eventually demonstrating dual-wavelength laser output.
ContributorsGreen, Benjamin C (Author) / Zhang, Yong-Hang (Thesis advisor) / Ning, Cun-Zheng (Committee member) / Tao, Nongjian (Committee member) / Roedel, Ronald J (Committee member) / Arizona State University (Publisher)
Created2011
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Description

This 15-week long course is designed to introduce students, specifically in Arizona, to basic sustainability and conservation principles in the context of local reptile wildlife. Throughout the course, the students work on identifying the problem, creating visions for the desired future, and finally developing a strategy to help with reptile

This 15-week long course is designed to introduce students, specifically in Arizona, to basic sustainability and conservation principles in the context of local reptile wildlife. Throughout the course, the students work on identifying the problem, creating visions for the desired future, and finally developing a strategy to help with reptile species survival in the valley. Research shows that animals in the classroom have led to improved academic success for students. Thus, through creating this course I was able to combine conservation and sustainability curriculum with real-life animals whose survival is directly being affected in the valley. My hope is that this course will help students identify a newfound passion and call to action to protect native wildlife. The more awareness and actionable knowledge which can be brought to students in Arizona about challenges to species survival the more likely we are to see a change in the future and a stronger sense of urgency for protecting wildlife. In order to accomplish these goals, the curriculum was developed to begin with basic concepts of species needs such as food and shelter and basic principles of sustainability. As the course progresses the students analyze current challenges reptile wildlife faces, like urban sprawl, and explore options to address these challenges. The course concludes with a pilot pitch where students present their solution projects to the school.

ContributorsGoethe, Emma Rae (Author) / Brundiers, Katja (Thesis director) / Bouges, Olivia (Committee member) / School of Sustainability (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Universal Basic Income is a proposed policy where the government would regularly pay all citizens in cash. The idea of a Universal Basic Income (UBI) has had a resurgence in recent years because of popular figures like Andrew Yang and Elon Musk, but its history and potential implications go dee

Universal Basic Income is a proposed policy where the government would regularly pay all citizens in cash. The idea of a Universal Basic Income (UBI) has had a resurgence in recent years because of popular figures like Andrew Yang and Elon Musk, but its history and potential implications go deep into the structure of human society. This thesis delves into how a basic income would transform social concepts of work and disrupt the personal economic model. With the bargaining power and freedom granted by a basic income, workers would find themselves in a position of work freedom and choice that has never existed in human history. With new freedom to do as they wish, the place of work in people’s lives needs to be reimagined as a source of fulfillment instead of an unlikeable but necessary part of everyday life. Workers will be given the choice to leave unfair or unfulfilling work and decide for themselves how they want to contribute within society. From increasing mental and economic well-being for most Americans to serving as a response to unemployment trends in the automated future, to encouraging greater business innovation, there are myriad ways in which basic incomes have the potential to benefit society. Framed by Martin Luther King Jr. and Franklin Delano Roosevelt as the only policy capable of abolishing poverty forever, Universal Basic income will be an important feature of transformative innovative policy advocacy until it is adopted by a major world government at which point the effects in practice will become clear.

ContributorsSimm, Michael Anthony (Author) / Soares, Rebecca (Thesis director) / Voorhees, Matthew (Committee member) / School of Sustainability (Contributor) / School of Politics and Global Studies (Contributor) / School for the Future of Innovation in Society (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Globally, the incidental capture of non-target species in fisheries (bycatch) has been linked to declines of ecologically, economically, and culturally important marine species. Gillnet fisheries have especially high bycatch due to their non-selective nature, necessitating the development of new bycatch reduction technologies (BRTs). Net illumination is an emerging BRT that

Globally, the incidental capture of non-target species in fisheries (bycatch) has been linked to declines of ecologically, economically, and culturally important marine species. Gillnet fisheries have especially high bycatch due to their non-selective nature, necessitating the development of new bycatch reduction technologies (BRTs). Net illumination is an emerging BRT that has shown promise in reducing bycatch of marine megafauna, including sea turtles, cetaceans, and seabirds. However, little research has been conducted to understand the effects of net illumination on fish assemblages, including bony fish and elasmobranchs (i.e. sharks, rays, and skates). Here, I assessed a 7-year dataset of paired net illumination trials using four different types of light (green LEDs, green chemical glowsticks, ultraviolet (UV) lights, and orange lights) to examine the effects of net illumination on fish catch and bycatch in a gillnet fishery at Baja California Sur, Mexico. Analysis revealed no significant effect on bony fish target catch or bycatch for any light type. There was a significant decrease in elasmobranch bycatch using UV and orange lights, with orange lights showing the most promise for decreasing elasmobranch bycatch, resulting in a 50% reduction in bycatch rates. Analysis of the effects of net illumination on elasmobranch target catch was limited due to insufficient data. These results indicate that the illumination of gillnets may offer a practical solution for reducing fish bycatch while maintaining target catch. More research should be conducted to understand the effects of net illumination in different fisheries, how net illumination affects fisher profit and efficiency, and how net illumination affects fish behavior. Further optimization of net illumination is also necessary before the technology can be recommended on a broader scale.

ContributorsBurgher, Kayla Marie (Author) / Senko, Jesse (Thesis director) / Throop, Heather (Committee member) / School of Life Sciences (Contributor) / School of Sustainability (Contributor) / School of Geographical Sciences and Urban Planning (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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As climate change continues to escalate natural hazards around the globe, certain communities feel the impacts of these disasters more so than others. After Hurricane Maria devastated communities in 2017, Puerto Rico struggled to respond to the needs of its citizens, particularly those in rural areas. Many of the regions

As climate change continues to escalate natural hazards around the globe, certain communities feel the impacts of these disasters more so than others. After Hurricane Maria devastated communities in 2017, Puerto Rico struggled to respond to the needs of its citizens, particularly those in rural areas. Many of the regions affected did not have resilient community structures in place to be able to withstand the systemic ripple effects of the hurricane. However, various community endeavors have developed post-Hurricane Maria to foster community collaboration and resiliency, including the development of agricultural tourism, otherwise known as agritourism. <br/>Although agritourism has begun to develop in rural regions of Puerto Rico, including the municipalities of Utuado, Ciales, Florida, and Jayuya, a systems-understanding is lacking of the current agritourism situation in the region and its related capacities, limitations, and opportunities of agritourism. To address this gap, a spatially explicit understanding and map of the underlying tourism infrastructure is needed to support the development of sustainable agritourism in Utuado, Jayuya, Ciales, and Florida municipalities in Puerto Rico. <br/>This report spatially represents the current state of tourism opportunities in the region as a result of asking “What are the spatial networks of gastronomy, accommodations, farms, and attractions that support the development of agritourism in Utuado, Jayuya, Ciales and Florida municipalities in Puerto Rico?” Three steps lead to the spatial representation starting with developing a comprehensive inventory. Second, we visualize the spatial map through Google Maps. Lastly, we explore the larger context of the report through an ArcGIS Storymap. The inventory will help with better understanding the number and variety of tourism resources available. The spatial visualization will help with understanding the distribution of resources and explore potential connections between resources and what relationships could be fostered in the future. Lastly, the ArcGIS Storymap will serve as a framework for outlining the future development of the SARE project. Overall, this report outlines the spatial maps of tourism resources and provides a tool to be used by community partners, tourists, and project partners.

ContributorsCretors, Kasey Ann (Author) / Brundiers, Katja (Thesis director) / Holladay, Patrick (Committee member) / Lazaro, Pablo Mendez (Committee member) / School of International Letters and Cultures (Contributor) / School of Sustainability (Contributor) / Division of Teacher Preparation (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Bioluminescent algae has long fascinated humans as a beautiful natural phenomenon. This creative project uses bioluminescent algae to push the limit of biomimicry, using the algae not as a model but as a technology. Through experimentation with algae samples and industrial design, two potential applications of bioluminescent algae as a

Bioluminescent algae has long fascinated humans as a beautiful natural phenomenon. This creative project uses bioluminescent algae to push the limit of biomimicry, using the algae not as a model but as a technology. Through experimentation with algae samples and industrial design, two potential applications of bioluminescent algae as a sustainable lighting technology were generated. One design focuses on indoor, private lighting, while the other focuses on outdoor, public lighting. Both outcomes attempt to solve problems generated by nighttime lighting including light pollution, wasted electricity usage, and negative impacts on human and environmental health while retaining the benefits of safety and convenience.

ContributorsFernald, Isabel (Author) / Shin, Dosun (Thesis director) / Feil, Magnus (Committee member) / The Design School (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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We analyzed multiple different models that can be utilized when measuring effects effects of fire and fire behavior in a forest ecosystem. In the thesis we focused on exploring ordinary differential equations, stochastic models, and partial differential equations

ContributorsVo, Sabrina (Author) / Jones, Donald (Thesis director) / Parker, Nathan (Committee member) / School of Mathematical and Statistical Sciences (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05