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Description
Synechocystis sp PCC 6803 is a photosynthetic cyanobacterium that can be easily transformed to produce molecules of interest; this has increased Synechocystis’ popularity as a clean energy platform. Synechocystis has been shown to produce and excrete molecules such as fatty acids, isoprene, etc. after appropriate genetic modification. Challenges faced for

Synechocystis sp PCC 6803 is a photosynthetic cyanobacterium that can be easily transformed to produce molecules of interest; this has increased Synechocystis’ popularity as a clean energy platform. Synechocystis has been shown to produce and excrete molecules such as fatty acids, isoprene, etc. after appropriate genetic modification. Challenges faced for large–scale growth of modified Synechocystis include abiotic stress, microbial contamination and high processing costs of product and cell material. Research reported in this dissertation contributes to solutions to these challenges. First, abiotic stress was addressed by overexpression of the heat shock protein ClpB1. In contrast to the wild type, the ClpB1 overexpression mutant (Slr1641+) tolerated rapid temperature changes, but no difference was found between the strains when temperature shifts were slower. Combination of ClpB1 overexpression with DnaK2 overexpression (Slr1641+/Sll0170+) further increased thermotolerance. Next, we used a Synechocystis strain that carries an introduced isoprene synthase gene (IspS+) and that therefore produces isoprene. We attempted to increase isoprene yields by overexpression of key enzymes in the methyl erythritol phosphate (MEP) pathway that leads to synthesis of the isoprene precursor. Isoprene production was not increased greatly by MEP pathway induction, likely because of limitations in the affinity of the isoprene synthase for the substrate. Finally, two extraction principles, two–phase liquid extraction (e.g., with an organic and aqueous phase) and solid–liquid extraction (e.g., with a resin) were tested. Two–phase liquid extraction is suitable for separating isoprene but not fatty acids from the culture medium. Fatty acid removal required acidification or surfactant addition, which affected biocompatibility. Therefore, improvements of both the organism and product–harvesting methods can contribute to enhancing the potential of cyanobacteria as solar–powered biocatalysts for the production of petroleum substitutes.
ContributorsGonzalez Esquer, Cesar Raul (Author) / Vermaas, Willem (Thesis advisor) / Chandler, Douglas (Committee member) / Bingham, Scott (Committee member) / Nielsen, David (Committee member) / Arizona State University (Publisher)
Created2013
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Description
The F1Fo ATP synthase is required for energy conversion in almost all living organisms. The F1 complex is a molecular motor that uses ATP hydrolysis to drive rotation of the γ–subunit. It has not been previously possible to resolve the speed and position of the γ–subunit of the F1–ATPase as

The F1Fo ATP synthase is required for energy conversion in almost all living organisms. The F1 complex is a molecular motor that uses ATP hydrolysis to drive rotation of the γ–subunit. It has not been previously possible to resolve the speed and position of the γ–subunit of the F1–ATPase as it rotates during a power stroke. The single molecule experiments presented here measured light scattered from 45X91 nm gold nanorods attached to the γ–subunit that provide an unprecedented 5 μs resolution of rotational position as a function of time. The product of velocity and drag, which were both measured directly, resulted in an average torque of 63±8 pN nm for the Escherichia coli F1-ATPase that was determined to be independent of the load. The rotational velocity had an initial (I) acceleration phase 15° from the end of the catalytic dwell, a slow (S) acceleration phase during ATP binding/ADP release (15°–60°), and a fast (F) acceleration phase (60°–90°) containing an interim deceleration (ID) phase (75°–82°). High ADP concentrations decreased the velocity of the S phase proportional to 'ADP-release' dwells, and the F phase proportional to the free energy derived from the [ADP][Pi]/[ATP] chemical equilibrium. The decreased affinity for ITP increased ITP-binding dwells by 10%, but decreased velocity by 40% during the S phase. This is the first direct evidence that nucleotide binding contributes to F1–ATPase torque. Mutations that affect specific phases of rotation were identified, some in regions of F1 previously considered not to contribute to rotation. Mutations βD372V and γK9I increased the F phase velocity, and γK9I increased the depth of the ID phase. The conversion between S and F phases was specifically affected by γQ269L. While βT273D, βD305E, and αR283Q decreased the velocity of all phases, decreases in velocity due to βD302T, γR268L and γT82A were confined to the I and S phases. The correlations between the structural locations of these mutations and the phases of rotation they affect provide new insight into the molecular basis for F1–ATPase γ-subunit rotation.
ContributorsMartin, James (Author) / Frasch, Wayne D (Thesis advisor) / Chandler, Douglas (Committee member) / Gaxiola, Roberto (Committee member) / Yan, Hao (Committee member) / Arizona State University (Publisher)
Created2012
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Description
Teleosts have the most primitive adaptive immune system. However, in terms of functionality the teleost immune system is similar to birds and mammals. On the other hand, enteric bacterial pathogens of mammals and birds present conserved regulatory mechanisms that control virulence factors. In this context, deletion of conserved genes that

Teleosts have the most primitive adaptive immune system. However, in terms of functionality the teleost immune system is similar to birds and mammals. On the other hand, enteric bacterial pathogens of mammals and birds present conserved regulatory mechanisms that control virulence factors. In this context, deletion of conserved genes that control virulence factors have been successfully used as measure to construct live attenuated bacterial vaccines for mammals and birds. Here, I hypothesize that evolutionary conserved genes, which control virulence factors or are essential for bacterial physiology in Enterobacteriaceae, could be used as universal tools to design live attenuated recombinant bacterial vaccines from fish to mammals. The evolutionary conserved genes that control virulence factors, crp and fur, and the essential gene for the synthesis of the cell wall, asd, were studied in Edwardsiella ictaluri to develop a live recombinant vaccine for fish host. The genus Edwardsiella is one of the most ancient represent of the Enterobacteriaceae family. E. ictaluri, a host restricted pathogen of catfish (Ictalurus punctatus), is the causative agent of the enteric septicemia and one of the most important pathogens of this fish aquaculture. Although, crp and fur control different virulence factors in Edwardsiella, in comparison to other enterics, individual deletion of these genes triggered protective immune response at the systemic and mucosal level of the fish. Deletion of asdA gene allowed the creation of a balanced-lethal system to syntheses heterologous antigens. I concluded that crp, fur and asd could be universally used to develop live attenuate recombinant Enterobacteriaceae base vaccines for different hosts.
ContributorsSantander Morales, Javier Alonso (Author) / Curtiss, Roy Iii (Thesis advisor) / Chandler, Douglas (Committee member) / Chang, Yung (Committee member) / Shi, Yixin (Committee member) / Arizona State University (Publisher)
Created2012
Description
Skeletal muscle (SM) mitochondria generate the majority of adenosine triphosphate (ATP) in SM, and help regulate whole-body energy expenditure. Obesity is associated with alterations in SM mitochondria, which are unique with respect to their arrangement within cells; some mitochondria are located directly beneath the sarcolemma (i.e., subsarcolemmal (SS) mitochondria), while

Skeletal muscle (SM) mitochondria generate the majority of adenosine triphosphate (ATP) in SM, and help regulate whole-body energy expenditure. Obesity is associated with alterations in SM mitochondria, which are unique with respect to their arrangement within cells; some mitochondria are located directly beneath the sarcolemma (i.e., subsarcolemmal (SS) mitochondria), while other are nested between the myofibrils (i.e., intermyofibrillar (IMF) mitochondria). Functional and proteome differences specific to SS versus IMF mitochondria in obese individuals may contribute to reduced capacity for muscle ATP production seen in obesity. The overall goals of this work were to (1) isolate functional muscle SS and IMF mitochondria from lean and obese individuals, (2) assess enzyme activities associated with the electron transport chain and ATP production, (3) determine if elevated plasma amino acids enhance SS and IMF mitochondrial respiration and ATP production rates in SM of obese humans, and (4) determine differences in mitochondrial proteome regulating energy metabolism and key biological processes associated with SS and IMF mitochondria between lean and obese humans.

Polarography was used to determine functional differences in isolated SS and IMF mitochondria between lean (37 ± 3 yrs; n = 10) and obese (35 ± 3 yrs; n = 11) subjects during either saline (control) or amino acid (AA) infusions. AA infusion increased ADP-stimulated respiration (i.e., coupled respiration), non-ADP stimulated respiration (i.e., uncoupled respiration), and ATP production rates in SS, but not IMF mitochondria in lean (n = 10; P < 0.05). Neither infusion increased any of the above parameters in muscle SS or IMF mitochondria of the obese subjects.

Using label free quantitative mass spectrometry, we determined differences in proteomes of SM SS and IMF mitochondria between lean (33 ± 3 yrs; n = 16) and obese (32 ± 3 yrs; n = 17) subjects. Differentially-expressed mitochondrial proteins in SS versus IMF mitochondria of obese subjects were associated with biological processes that regulate: electron transport chain (P<0.0001), citric acid cycle (P<0.0001), oxidative phosphorylation (P<0.001), branched-chain amino acid degradation, (P<0.0001), and fatty acid degradation (P<0.001). Overall, these findings show that obesity is associated with redistribution of key biological processes within the mitochondrial reticulum responsible for regulating energy metabolism in human skeletal muscle.
ContributorsKras, Katon Anthony (Author) / Katsanos, Christos (Thesis advisor) / Chandler, Douglas (Committee member) / Dinu, Valentin (Committee member) / Mor, Tsafrir S. (Committee member) / Arizona State University (Publisher)
Created2017
Description
The saxophone is privileged to have a wide variety of repertoire from contemporary composers. Due to its invention in the later half of the nineteenth century, it has no repertoire written by baroque composers, including Johann Sebastian Bach. There are several published arrangements of Bach’s three solo violin partitas including

The saxophone is privileged to have a wide variety of repertoire from contemporary composers. Due to its invention in the later half of the nineteenth century, it has no repertoire written by baroque composers, including Johann Sebastian Bach. There are several published arrangements of Bach’s three solo violin partitas including that of Ronald Caravan and Raaf Hekkema. These collections either do not present every movement of each of these three partitas, or they do not present them in their original keys. An advantage to arranging these works in their original keys is that saxophonists have the opportunity to learn more about the works by playing along with recordings of great violinists such as Itzhak Perlman and Hilary Hahn, something that would be very difficult to do if they were not in the original keys. In Ronald Caravan’s Bach for Solo Saxophone, Caravan includes a collection of many unaccompanied works by Bach for saxophone but does not include all of the movements from the three partitas and they are not in the original keys that Bach wrote for. In Raaf Hekkema’s Bach for Saxophone, Hekkema arranges the entirety of the three partitas, however they are not set in the original keys that Bach wrote for. In addition to these points, those collections do not provide information of the life of J.S. Bach, baroque performance practice, mechanics of the baroque violin, baroque dances, and advice on going about the mechanics of these pieces from a saxophonist’s perspective. This information is very useful to a young saxophonist who is trying to fully understand and perform Bach’s three solo violin partitas.
ContributorsSalazar, Nathan John (Author) / Creviston, Christopher (Thesis director) / Saucier, Catherine (Committee member) / School of Music (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Description
This creative project explores the concept of how music is like a language and how, as a teacher, I plan to enforce this concept through my teaching. The aim of this project is to highlight the importance of completing research and acquiring knowledge of aspects, such as the composer's life,

This creative project explores the concept of how music is like a language and how, as a teacher, I plan to enforce this concept through my teaching. The aim of this project is to highlight the importance of completing research and acquiring knowledge of aspects, such as the composer's life, historical background and literary references, when learning a piece of music. Through this project, I address connections between the brain and music pertaining to memorization, the components of language, the similarities between language and music, the role of the teacher and the development of a "toolbox" of knowledge for studying a piece of music. I present my own research on Schumann's Novelette Op. 21, No. 8 in f-sharp minor as well as my own experiences of learning the piece to demonstrate an example of the process and discoveries I hope my students will make in their own studies of repertoire.
ContributorsLee, Kara Jia-Shan (Author) / Pagano, Caio (Thesis director) / Creviston, Hannah (Committee member) / Division of Teacher Preparation (Contributor) / School of Music (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
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Description
The SolarSPELL is an offline, ruggedized, digital library, created by Dr. Laura Hosman for the U.S. Peace Corps. It has thousands of pieces of educational content that can be accessed through a self-contained Wi-Fi hotspot on the device itself. Currently, there are more than 200 deployed in several Pacific Island

The SolarSPELL is an offline, ruggedized, digital library, created by Dr. Laura Hosman for the U.S. Peace Corps. It has thousands of pieces of educational content that can be accessed through a self-contained Wi-Fi hotspot on the device itself. Currently, there are more than 200 deployed in several Pacific Island nations. After visiting one of these nations, Tonga, in December of 2016, I learned that almost all of the Peace Corps volunteers stationed around the Pacific Islands suffered from a lack of resources due to a variety of reasons. While the SolarSPELL helps to remedy that, the device is lacking classroom activities and resources for creative work and educational drama. Furthermore, for many students in these environments, schools are for learning information and producing high scores on exams, not for learning about creative strengths and identity. After researching curriculum development and the use of drama in an educational setting, I compiled over 50 pieces of content to include on the SolarSPELL involving art, drama, music, movement, and most importantly, imagination. These resources will allow Peace Corps volunteers to explore additional ways to teach English in their schools, while also creating a classroom environment that allows for creative expression. All the content is compiled into one folder as "Teaching Resources", and is then broken down into seven sub- categories. In the first sub-category, Art Projects, there is a collection of several hands-on projects, many of which involve recyclable or readily available materials. These projects will allow for a greater understanding of conservation and "green" living, concepts that are crucial to the stability of these island nations. The next 5 categories are Drama Readings, Music, Movement, and Video, Group Exercises, Creative Writing, and Worksheets. The second sub- category is a collection of beginner-level "Reader's Theater" scripts. The third sub-category involves music and video to engage students in movement activities. The fourth sub-category is a compilation of group games and activities to help students express themselves and learn social skills. The fifth sub-category includes a collection of activities such as fill-in-the-blank story worksheets and journal prompts which will aid in creative thinking and the practice of the English language. The sixth sub-category involves a collection of worksheets that mainly focus on self-reflection and identity. The seventh and final sub-category, Content Guide and Information, works to explain the benefits of using of drama and creative play in the classroom, as well as strategies teachers can implement in order to further engage their students in dramatic learning and play. Overall, these pieces of content are meant to be used as resources for the Peace Corps volunteers in order to provide alternative ways to practice reading, writing, and speaking the English language, a critical part of education in the Pacific Islands.
ContributorsTaylor, Amanda Nicole (Author) / Hosman, Laura (Thesis director) / McAvoy, Mary (Committee member) / School of Film, Dance and Theatre (Contributor) / Division of Teacher Preparation (Contributor) / Barrett, The Honors College (Contributor) / School for the Future of Innovation in Society (Contributor)
Created2017-12
Description
This creative project thesis involves electronic music composition and production, and it uses some elements of algorithmic music composition (through recurrent neural networks). Algorithmic composition techniques are used here as a tool in composing the pieces, but are not the main focus. Thematically, this project explores the analogy between artificial

This creative project thesis involves electronic music composition and production, and it uses some elements of algorithmic music composition (through recurrent neural networks). Algorithmic composition techniques are used here as a tool in composing the pieces, but are not the main focus. Thematically, this project explores the analogy between artificial neural networks and neural activity in the brain. This project consists of three short pieces, each exploring these concept in different ways.
ContributorsKarpur, Ajay (Author) / Suzuki, Kotoka (Thesis director) / Ingalls, Todd (Committee member) / Electrical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Description
Musical interpretation is challenging when one's goal is to evoke an emotional response from an audience. In order to develop a well-informed interpretation of Mozart's Fantasia in D minor K. 397, a study was conducted on the historical background of the piece and various performances by well-regarded performers. Fantasias are

Musical interpretation is challenging when one's goal is to evoke an emotional response from an audience. In order to develop a well-informed interpretation of Mozart's Fantasia in D minor K. 397, a study was conducted on the historical background of the piece and various performances by well-regarded performers. Fantasias are written works, but improvisatory by nature. Mozart's fantasias were influenced by C. P. E. Bach's, which included sudden changes in emotion. An Emil Gilels performance provided a classically trained approach, while Mitsuko Uchida's performance provided an emotional approach. Colin Tilney and John Irving performances elucidated the sound of the instruments that Mozart would have been composing with. Altogether, the research culminated in an interpretation of the D minor Fantasia that endeavored to capture the essence of fantasy, improvisation and emotion.
ContributorsMo, Gina Nan (Author) / Emmery, Laura (Thesis director) / Creviston, Hannah (Committee member) / Department of Psychology (Contributor) / School of International Letters and Cultures (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Description
The purpose of this study is to analyze the stereotypes surrounding four wind instruments (flutes, oboes, clarinets, and saxophones), and the ways in which those stereotypes propagate through various levels of musical professionalism in Western culture. In order to determine what these stereotypes might entail, several thousand social media and

The purpose of this study is to analyze the stereotypes surrounding four wind instruments (flutes, oboes, clarinets, and saxophones), and the ways in which those stereotypes propagate through various levels of musical professionalism in Western culture. In order to determine what these stereotypes might entail, several thousand social media and blog posts were analyzed, and direct quotations detailing the perceived stereotypical personality profiles for each of the four instruments were collected. From these, the three most commonly mentioned characteristics were isolated for each of the instrument groups as follows: female gender, femininity, and giggliness for flutists, intelligence, studiousness, and demographics (specifically being an Asian male) for clarinetists, quirkiness, eccentricity, and being seen as a misfit for oboists, and overconfidence, attention-seeking behavior, and coolness for saxophonists. From these traits, a survey was drafted which asked participating college-aged musicians various multiple choice, opinion scale, and short-answer questions that gathered how much they agree or disagree with each trait describing the instrument from which it was derived. Their responses were then analyzed to determine how much correlation existed between the researched characteristics and the opinions of modern musicians. From these results, it was determined that 75% of the traits that were isolated for a particular instrument were, in fact, recognized as being true in the survey data, demonstrating that the stereotypes do exist and seem to be widely recognizable across many age groups, locations, and levels of musical skill. Further, 89% of participants admitted that the instrument they play has a certain stereotype associated with it, but only 38% of people identify with that profile. Overall, it was concluded that stereotypes, which are overwhelmingly negative and gendered by nature, are indeed propagated, but musicians do not appear to want to identify with them, and they reflect a more archaic and immature sense that does not correlate to the trends observed in modern, professional music.
ContributorsAllison, Lauren Nicole (Author) / Bhattacharjya, Nilanjana (Thesis director) / Ankeny, Casey (Committee member) / School of Life Sciences (Contributor) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05