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Description
A dual-channel directional digital hearing aid (DHA) front-end using a fully differential difference amplifier (FDDA) based Microphone interface circuit (MIC) for a capacitive Micro Electro Mechanical Systems (MEMS) microphones and an adaptive-power analog font end (AFE) is presented. The Microphone interface circuit based on FDDA converts

A dual-channel directional digital hearing aid (DHA) front-end using a fully differential difference amplifier (FDDA) based Microphone interface circuit (MIC) for a capacitive Micro Electro Mechanical Systems (MEMS) microphones and an adaptive-power analog font end (AFE) is presented. The Microphone interface circuit based on FDDA converts the capacitance variations into voltage signal, achieves a noise of 32 dB SPL (sound pressure level) and an SNR of 72 dB, additionally it also performs single to differential conversion allowing for fully differential analog signal chain. The analog front-end consists of 40dB VGA and a power scalable continuous time sigma delta ADC, with 68dB SNR dissipating 67u¬W from a 1.2V supply. The ADC implements a self calibrating feedback DAC, for calibrating the 2nd order non-linearity. The VGA and power scalable ADC is fabricated on 0.25 um CMOS TSMC process. The dual channels of the DHA are precisely matched and achieve about 0.5dB gain mismatch, resulting in greater than 5dB directivity index. This will enable a highly integrated and low power DHA
ContributorsNaqvi, Syed Roomi (Author) / Kiaei, Sayfe (Thesis advisor) / Bakkaloglu, Bertan (Committee member) / Chae, Junseok (Committee member) / Barnby, Hugh (Committee member) / Aberle, James T., 1961- (Committee member) / Arizona State University (Publisher)
Created2011
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Description
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
Alzheimer's Disease (AD) is a debilitating neurodegenerative disease. The disease leads to dementia and loss of cognitive functions and affects about 4.5 million people in the United States. It is the 7th leading cause of death and is a huge financial burden on the healthcare industry. There are no means

Alzheimer's Disease (AD) is a debilitating neurodegenerative disease. The disease leads to dementia and loss of cognitive functions and affects about 4.5 million people in the United States. It is the 7th leading cause of death and is a huge financial burden on the healthcare industry. There are no means of diagnosing the disease before neurodegeneration is significant and sadly there is no cure that controls its progression. The protein beta-amyloid or Aâ plays an important role in the progression of the disease. It is formed from the cleavage of the Amyloid Precursor Protein by two enzymes - â and ã-secretases and is found in the plaques that are deposits found in Alzheimer brains. This work describes the generation of therapeutics based on inhibition of the cleavage by â-secretase. Using in-vitro recombinant antibody display libraries to screen for single chain variable fragment (scFv) antibodies; this work describes the isolation and characterization of scFv that target the â-secretase cleavage site on APP. This approach is especially relevant since non-specific inhibition of the enzyme may have undesirable effects since the enzyme has been shown to have other important substrates. The scFv iBSEC1 successfully recognized APP, reduced â-secretase cleavage of APP and reduced Aâ levels in a cell model of Alzheimer's Disease. This work then describes the first application of bispecific antibody therapeutics to Alzheimer's Disease. iBSEC1 scFv was combined with a proteolytic scFv that enhances the "good" pathway (á-secretase cleavage) that results in alternative cleavage of APP to generate the bispecific tandem scFv - DIA10D. DIA10D reduced APP cleavage by â-secretase and steered it towards the "good" pathway thus increasing the generation of the fragment sAPPá which is neuroprotective. Finally, treatment with iBSEC1 is evaluated for reduced oxidative stress, which is observed in cells over expressing APP when they are exposed to stress. Recombinant antibody based therapeutics like scFv have several advantages since they retain the high specificity of the antibodies but are safer since they lack the constant region and are smaller, potentially facilitating easier delivery to the brain
ContributorsBoddapati, Shanta (Author) / Sierks, Michael (Thesis advisor) / Arizona State University (Publisher)
Created2011
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Description
In this work, a novel method is developed for making nano- and micro- fibrous hydrogels capable of preventing the rejection of implanted materials. This is achieved by either (1) mimicking the native cellular environment, to exert fine control over the cellular response or (2) acting as a protective barrier, to

In this work, a novel method is developed for making nano- and micro- fibrous hydrogels capable of preventing the rejection of implanted materials. This is achieved by either (1) mimicking the native cellular environment, to exert fine control over the cellular response or (2) acting as a protective barrier, to camouflage the foreign nature of a material and evade recognition by the immune system. Comprehensive characterization and in vitro studies described here provide a foundation for developing substrates for use in clinical applications. Hydrogel dextran and poly(acrylic acid) (PAA) fibers are formed via electrospinning, in sizes ranging from nanometers to microns in diameter. While "as-electrospun" fibers are continuous in length, sonication is used to fragment fibers into short fiber "bristles" and generate nano- and micro- fibrous surface coatings over a wide range of topographies. Dex-PAA fibrous surfaces are chemically modified, and then optimized and characterized for non-fouling and ECM-mimetic properties. The non-fouling nature of fibers is verified, and cell culture studies show differential responses dependent upon chemical, topographical and mechanical properties. Dex-PAA fibers are advantageously unique in that (1) a fine degree of control is possible over three significant parameters critical for modifying cellular response: topography, chemistry and mechanical properties, over a range emulating that of native cellular environments, (2) the innate nature of the material is non-fouling, providing an inert background for adding back specific bioactive functionality, and (3) the fibers can be applied as a surface coating or comprise the scaffold itself. This is the first reported work of dex-PAA hydrogel fibers formed via electrospinning and thermal cross-linking, and unique to this method, no toxic solvents or cross-linking agents are needed to create hydrogels or for surface attachment. This is also the first reported work of using sonication to fragment electrospun hydrogel fibers, and in which surface coatings were made via simple electrostatic interaction and dehydration. These versatile features enable fibrous surface coatings to be applied to virtually any material. Results of this research broadly impact the design of biomaterials which contact cells in the body by directing the consequent cell-material interaction.
ContributorsLouie, Katherine BoYook (Author) / Massia, Stephen P (Thesis advisor) / Bennett, Kevin (Committee member) / Garcia, Antonio (Committee member) / Pauken, Christine (Committee member) / Vernon, Brent (Committee member) / Arizona State University (Publisher)
Created2011
Description

Soiled: An Environmental Podcast is a six episode series that addresses common environmental topics and debunks myths that surround those topics.

ContributorsTurner, Natalie Ann (Co-author) / Kuta, Tiffany (Co-author) / Jones, Cassity (Co-author) / Boyer, Mackenzie (Thesis director) / Ward, Kristen (Committee member) / Materials Science and Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

For this Creative Project, I decided to explore the elements that set novellas apart from other genres and then experiment writing in the form. In doing so, I took into account three main categories: Plot Structure, Character Development, Style/Format, and then used my findings to write 45 pages of a

For this Creative Project, I decided to explore the elements that set novellas apart from other genres and then experiment writing in the form. In doing so, I took into account three main categories: Plot Structure, Character Development, Style/Format, and then used my findings to write 45 pages of a novella titled Emmy and Me.

ContributorsBingham, Roxanne Marie (Author) / Irish, Jennifer (Thesis director) / Danielson, Jonathan (Committee member) / Department of English (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description

Filmmakers seek to create story pieces that are visually beautiful and engage the full attention of their audience. They typically abide by a 3-step process moving through pre-production, production, and post-production. Within each step, there are a series of tasks that need to be accomplished in order to reach the

Filmmakers seek to create story pieces that are visually beautiful and engage the full attention of their audience. They typically abide by a 3-step process moving through pre-production, production, and post-production. Within each step, there are a series of tasks that need to be accomplished in order to reach the completed film. A successful film requires careful planning and strategy in pre-production, timely and decisive execution in production, and minimal unforeseen retouching in post-production.<br/><br/>Even though filmmakers have continued to follow the same formula throughout the decades, the filmmaking process has remained largely inefficient. It is extremely common for pre-production planning to be undercut, for production filming to run far too long, and for post-production VFX and editing to send the project over budget. These instances can cause major issues as the project is being finalized. In many scenarios portions of the project need to be reshot, the box office revenue isn’t enough to make up for extensive VFX retouching, or the project may never even come to fruition. <br/><br/>The reason for this recurring theme of films being over budget and out of time is quite simply that technology has made filmmakers lazy. “Fix it in post” is a disgustingly common phrase used in the film industry. It describes the utter abuse of computer retouching in the post-production phase of filmmaking. Despite working in an industry that seeks to entertain the human eye, filmmakers have become blind to all of the small mistakes that could cost them hundreds of hours and millions of dollars in the long run.

ContributorsKlewicki, Tallee Jo (Author) / Shin, Dosun (Thesis director) / Eliciana, Nascimento (Committee member) / The Design School (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

My project is designed to provide art education to incarcerated youth in Arizona. This project will address two current issues in Arizona; the underfunding of art programs and high rates of incarceration. As of 2021, there are no state-funded art programs in Arizona. Arizona is tied with Texas for the

My project is designed to provide art education to incarcerated youth in Arizona. This project will address two current issues in Arizona; the underfunding of art programs and high rates of incarceration. As of 2021, there are no state-funded art programs in Arizona. Arizona is tied with Texas for the eighth highest rate of incarceration in the country. In Arizona, 750 out of every 100,000 people are incarcerated. This project is an art course for incarcerated youth. The project includes a packet detailing the course content and assignment details, a class syllabus, a course flyer, and a certificate of completion. The course is intended to be taught at the Adobe Mountain School facility. The course is designed so that it can be implemented in other facilities in the future. The class will be taught by volunteers with a background in studio art, design, or art education. Each student will receive a course packet that they can use to keep track of information and assignments. Instructors will use the course packet to teach the class. The course focuses on drawing with charcoal and oil pastel, which will build a foundation in drawing skills. The course covers a twelve-week semester. The course content packet includes a week-by-week breakdown of the teaching material and project descriptions. The course consists of two main projects and preparatory work. The preparatory work includes vocabulary terms, art concepts, drawing guides, brainstorming activities, and drawing activities. The two main prompts are designed for students to explore the materials and to encourage self-reflection. The class is curated so that students can create art in a low-risk, non-judgemental environment. The course will also focus on establishing problem-solving and critical thinking skills through engaging activities.

ContributorsSheppard, Eve (Author) / Cornelia, Wells (Thesis director) / Jennifer, Nelson (Committee member) / School of Art (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description

Soiled: An Environmental Podcast is a six episode series where common environmental topics are discussed and misconceptions surrounding these topics are debunked.

ContributorsKuta, Tiffany T (Co-author) / Jones, Cassity (Co-author) / Turner, Natalie (Co-author) / Boyer, Mackenzie (Thesis director) / Ward, Kristen (Committee member) / Civil, Environmental and Sustainable Eng Program (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description

Soiled: An Environmental Podcast is a six episode series where common environmental topics are discussed and misconceptions surrounding these topics are debunked.

ContributorsJones, Cassity Rachelle (Co-author) / Kuta, Tiffany (Co-author) / Turner, Natalie (Co-author) / Boyer, Mackenzie (Thesis director) / Ward, Kristen (Committee member) / School of Life Sciences (Contributor) / School of Human Evolution & Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05