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Title: Ultrafast transient states in nonequilibrium quantum systems
Creator: Hwang, Bin
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Photo-induced phase transitions (PIPT) in quantum systems are the epitome of challenging non-equilibrium many-body phenomena, that also have a wide range of potential applications. Recently interest in light-matter coupled states with an energy gap have yielded evidence for Floquet topological states. In this study we demonstrate nonequilibrium Floquet band formation under ultrafast optical excitation using a one-dimensional topological insulator. As an example, the effects are illustrated...
Show morePhoto-induced phase transitions (PIPT) in quantum systems are the epitome of challenging non-equilibrium many-body phenomena, that also have a wide range of potential applications. Recently interest in light-matter coupled states with an energy gap have yielded evidence for Floquet topological states. In this study we demonstrate nonequilibrium Floquet band formation under ultrafast optical excitation using a one-dimensional topological insulator. As an example, the effects are illustrated using a new Zig-Zag Su-Schrieffer-Heeger model of polyacetylene, which is a paradigmatic Hamiltonian exhibiting nontrivial edge states. Our results indicate short optical pulses feasible in experiments can induce novel topological states, local spectral selection and novel pseudospin textures in polyacetylene. Pump-probe photoemission spectroscopy is able to study these states by measuring Floquet band formation and sizeable energy gaps on femtosecond time scales. We find that optically activated nontrivial variations of sublattice mixing could lead to novel topological phenomenon.The rich variety of states induced by lasers have a wide range of potential applications so that control of these states has become a key objective. We present a computational approach to finding optimal ultrafast laser pulse shapes to induce target states and population inversion in pump-probe PIPT experiments. The Krotov approach for Quantum optimal control theory (QOCT) is combined with a Keldysh Green’s function calculation to describe experimental outcomes such as photoemission, transient single particle density of states and optical responses. Results for a simple model charge density wave (CDW) system are presented, including generation of almost complete population inversion and negative temperature states.
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Title: Field modeling, symplectic tracking, and spin decoherence for EDM and muon g-2 lattices
Creator: Valetov, Eremey Vladimirovich
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "While the first particle accelerators were electrostatic machines, and several electrostatic storage rings were subsequently commissioned and operated, electrostatic storage rings pose a number of challenges. Unlike motion in the magnetic field, where particle energy remains constant, particle energy generally changes in electrostatic elements. Conservation of energy in an electrostatic element is, in practice, only approximate, and it requires careful and accurate design, manufacturing,...
Show more"While the first particle accelerators were electrostatic machines, and several electrostatic storage rings were subsequently commissioned and operated, electrostatic storage rings pose a number of challenges. Unlike motion in the magnetic field, where particle energy remains constant, particle energy generally changes in electrostatic elements. Conservation of energy in an electrostatic element is, in practice, only approximate, and it requires careful and accurate design, manufacturing, installation, and operational use. Electrostatic deflectors require relatively high electrostatic fields, tend to introduce nonlinear aberrations of all orders, and are more challenging to manufacture than homogeneous magnetic dipoles. Accordingly, magnetic storage rings are overwhelmingly prevalent. The search for electric dipole moments (EDMs) of fundamental particles is of key importance in the study of C and CP violations and their sources. C and CP violations are part of the Sakharov conditions that explain the matter-antimatter asymmetry in the universe. Determining the source of CP violations would provide valuable empirical insight for beyond-Standard-Model physics. EDMs of fundamental particles have not to this date been experimentally observed. The search for fundamental particle EDMs has narrowed the target search region; however, an EDM signal is yet to be discovered. In 2008, Brookhaven National Laboratory (BNL) had proposed the frozen spin (FS) concept for the search of a deuteron EDM. The FS concept envisions launching deuterons through a storage ring with combined electrostatic and magnetic fields. The electrostatic and magnetic fields are in a proportion that would, without an EDM, freeze the deuteron's spin along its momentum as the deuteron moves around the lattice. The radial electrostatic field would result in a torque on the spin vector, proportional to a deuteron EDM, rotating the spin vector out of the midplane. The principle of an anomalous magnetic dipole moment (MDM) measurement using a storage ring, shared by BNL's completed E821 Experiment and the ongoing E989 Experiment operated by Fermi National Accelerator Laboratory (FNAL), requires injecting muons into a magnetic ring at the so-called magic momentum. The magic momentum, as defined in this context, would freeze the muon's spin vector along its momentum if the anomalous MDM was zero. The spin precession in the horizontal plane relative to the momentum is proportional to the anomalous MDM. Storage rings for measurement of EDM and anomalous MDM present a new frontier in tracking code accuracy requirements. For accurate tracking of storage rings with electrostatic particle optical elements, it is necessary to model the fringe fields of such elements accurately, in particular, because not doing so provides a mechanism for energy conservation violation. However, the previous research on fringe fields tended to focus on magnetic rather than electrostatic particle optical elements. We will study and model the fringe fields of several electrostatic deflectors. Field falloffs of electrostatic deflectors are slower than exponential, and Enge functions are not suitable for accurate modeling of these falloffs. We will propose an alternative function to model field falloffs of electrostatic deflectors. We will use conformal mapping methods to obtain the main field of the Muon g-2 storage ring high voltage quadrupole, and we will calculate its fringe field and effective field boundary (EFB) using Fourier analysis. Furthermore, we will study tracking of storage rings with electrostatic elements using map methods. We will find that, for simultaneous symplecticity and energy conservation, it is only necessary to enforce symplecticity in COSY INFINITY. We will model and track several benchmark lattices - an electrostatic spherical deflector, a homogeneous magnetic dipole, and a proton EDM lattice - in COSY INFINITY and MSURK89, our in-house eighth order Runge-Kutta-Verner tracking code. Finally, we will investigate spin decoherence and systematic errors in FS and quasifrozen spin (QFS) lattices. Spin decoherence effects are similar in FS and QFS lattices, and spin decoherence in said lattices often remains in the same range over time, indicating the feasibility of EDM measurement using FS and QFS lattices."--Pages ii-iii.
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Title: The limits of sympathy : professional philanthropy and detachment in narrative, 1869-1914
Creator: Beard, Erin Elizabeth
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The Limits of Sympathy intervenes in the scholarly conversation surrounding the relationship between philanthropic reform and the novel as well as the role of women in philanthropic work during late Victorian England. Importantly, this project brings archival texts, such as the philanthropic case reports of the Charity Organisation Society, into the conversation in order to demonstrate how the professionalization of philanthropy eliminated the role of sympathy in philanthropic work and...
Show moreThe Limits of Sympathy intervenes in the scholarly conversation surrounding the relationship between philanthropic reform and the novel as well as the role of women in philanthropic work during late Victorian England. Importantly, this project brings archival texts, such as the philanthropic case reports of the Charity Organisation Society, into the conversation in order to demonstrate how the professionalization of philanthropy eliminated the role of sympathy in philanthropic work and narrative. Where philanthropic texts created new narrative forms to grapple with the New Poor Laws and the changing urban environment of late Victorian London, novels by George Eliot, Walter Besant, H. G. Wells, Edith Johnstone, and Isabella Ford considered how the adoption of professionalized, distanced discourse affected women's perception of and participation in philanthropic work. These novels demonstrate how our current critical reliance on sympathy as a way to mediate the relationship between philanthropic and poor characters, as well as between reader and novel, no longer works within the context of professionalized philanthropy. -- Abstract.
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Title: Accusing Muslims of terrorism : Islam, secularism, and religious violence in the United States
Creator: Sadequee, Sharmin
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This dissertation describes the ways in which the securitized secular laws of the state act to regulate and control Muslims and the practices of Islam through "terrorism" prosecutions in the United States. In order to eliminate terrorism violence, the security state has created an exception to regular legal norms by establishing a court within a court and a prison within a prison, where normal legal procedures are not followed for those Muslim immigrants and American Muslim citizens accused...
Show moreThis dissertation describes the ways in which the securitized secular laws of the state act to regulate and control Muslims and the practices of Islam through "terrorism" prosecutions in the United States. In order to eliminate terrorism violence, the security state has created an exception to regular legal norms by establishing a court within a court and a prison within a prison, where normal legal procedures are not followed for those Muslim immigrants and American Muslim citizens accused of "terrorism" related offenses. I address the ways in which Muslims have been conditioned and affected by the securitized secular laws that are applied in "terrorism" cases, and I also discuss how human-rights advocacy around the accused challenge and resist these discriminatory practices. Based on 24 months of ethnographic fieldwork; observations of federal terrorism trials; a review of prison writings; and interviews with families of the accused, activists, lawyers, and human-rights advocates, I address the legal practices of securitized laws concerned with preventing "terrorism," their impact both inside and outside of judicial institutions, and the power of these practices on the lived experiences of Muslim Americans. While some authorities claim that preventive "terrorism" prosecutions are necessary to eradicate violence, I suggest that the main concerns of the security state are really about eradicating religious thought and practices that contradict the secular definition of acceptable religion. -- Abstract.
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Title: "One leg in one, and one leg in the other" : reflections of vernacular musicians as music educators
Creator: Adams, Mark C.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: With a purpose of improving the experiences of vernacular musicians who want to become music educators so that more vernacular music-making can occur in K-12 music settings, this study explored the lived musical experiences of two vernacular musicians who successfully became music educators. The two grand tour problems of this study were:1. To describe how two vernacular musicians navigated their undergraduate music education programs.2. To describe if/how their vernacular musicianship...
Show moreWith a purpose of improving the experiences of vernacular musicians who want to become music educators so that more vernacular music-making can occur in K-12 music settings, this study explored the lived musical experiences of two vernacular musicians who successfully became music educators. The two grand tour problems of this study were:1. To describe how two vernacular musicians navigated their undergraduate music education programs.2. To describe if/how their vernacular musicianship contributed to their practice as music teachers. Ethnographic techniques were used within the framework of a multiple narrative case study to present the viewpoints of two participants, Carrie and Harrison (pseudonyms). Both were vernacular musicians prior to pursuing degrees in music education. The two participants’ stories revealed that they felt like they were living in two musical worlds. In their undergraduate experiences, participants felt their Western classical abilities were more highly valued than their vernacular musicianship skills, and they did not feel fully supported by faculty musically. In their teaching lives, their vernacular music-making backgrounds manifested through aural learning and rote teaching, creating, and their classroom environment. Participants experienced feelings of being an impostor during their undergraduate experiences, which, particularly for one participant, created fear and anxiety. These feelings of being an impostor continued into their teaching lives, typically brought about by preconceived program expectations (e.g., performance schedules, high-level student musical performance abilities) from community members and colleagues. These outside influences, at times, determined what vernacular music-making experiences they implemented into their classrooms and when it was “safe” to do so.Based on these data, I suggest institutions of higher education more equally value musics found outside Western classical cultures. This includes an evaluation of their audition processes, the support provided to “non-traditional” students, as well as a re-envisioning of required coursework, field experiences, and performance ensembles. Additionally, I suggest ways that teachers of K–12 musics can create a more diverse music education experience for students by including more vernacular music making. These suggestions include opportunities for informal learning, creative music making, and considerations for the classroom environment.
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Title: Exploring the relationship of criminogenic need, risk of recidivism, official recidivism, and gang status in youth offenders
Creator: Mandalari, Amber Angelina
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Research indicates that gang-involved youth are at risk for numerous negative outcomes, including elevated risk of involvement with the juvenile justice system. While many studies have examined the differences between gang-involved youth and their non-gang, non-delinquent peers, differences among non-gang and gang-involved juvenile delinquents have been less explored. This study explored the relationship of areas of criminogenic need, risk of recidivism, and official recidivism between gang...
Show more"Research indicates that gang-involved youth are at risk for numerous negative outcomes, including elevated risk of involvement with the juvenile justice system. While many studies have examined the differences between gang-involved youth and their non-gang, non-delinquent peers, differences among non-gang and gang-involved juvenile delinquents have been less explored. This study explored the relationship of areas of criminogenic need, risk of recidivism, and official recidivism between gang and non-gang justice-involved youth using the Youth Level of Service/Case Management Inventory (YLS/CMI). Results from regression analyses suggest gang status is positively associated with scores of criminogenic needs, risk of recidivism, and official recidivism. However, gang status was not found to moderate the predictive validity of the YLS/CMI for official recidivism. These results indicated it is important for justice system practitioners to consider gang status when making programming and intervention decisions. Limitations and future directions are also discussed."--Page ii.
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Title: A practical approach for ultra high performance concrete construction
Creator: Chen, Yang (Graduate of Michigan State University in civil engineering)
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Ultra-high-performance concrete (UHPC) with compressive strengths in excess of 150 MPa promise to enhance the structural efficiency and durability of concrete-based infrastructure systems. In order to transition UHPC materials into mainstream construction practices, there are needs to develop refined mix design procedures that enable production of UHPC using primarily locally available materials, resolves the problems with production of homogeneous UHPC mixtures using commonly available...
Show more"Ultra-high-performance concrete (UHPC) with compressive strengths in excess of 150 MPa promise to enhance the structural efficiency and durability of concrete-based infrastructure systems. In order to transition UHPC materials into mainstream construction practices, there are needs to develop refined mix design procedures that enable production of UHPC using primarily locally available materials, resolves the problems with production of homogeneous UHPC mixtures using commonly available concrete mixers, develop convenient fresh mix workability test methods that consider the peculiar rheology of fresh UHPC mixtures, and quantify some aspects of the UHPC material properties that have not been fully characterized. The UHPC materials were tested for fresh mix flow and hardened concrete compressive strength. The trends in the effects of packing density, water film thickness and excess paste film thickness on compressive strength and fresh mix flow were investigated. The results were used to identify viable ranges of these defining characteristics of UHPC mixtures. Response surface analysis of the fresh mix flow and the hardened concrete compressive strength test results led to identification of the optimum values of mix design parameters. The optimum mix was prepared, and was found to produce a highly desired balance of fresh mix flow and hardened concrete compressive strength, which occurred within the ranges predicted by response surface analysis of experimental results."--Page ii.
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Title: Urban and cluster agglomeration economies's effects on rural households in Asia
Creator: Hu, Chaoran
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Agglomeration effects play important roles for rural households in participating in farm and nonfarm activities. With the rapid growth of cities of different sizes and the development of food value chain, how these agglomerations of urban effects, networks, and food value chain clusters will affect rural households' participation in nonfarm employment and farm behavior (technology adoption) are not yet well known. The dissertation consists of three chapters that aim to assess the impacts of...
Show more"Agglomeration effects play important roles for rural households in participating in farm and nonfarm activities. With the rapid growth of cities of different sizes and the development of food value chain, how these agglomerations of urban effects, networks, and food value chain clusters will affect rural households' participation in nonfarm employment and farm behavior (technology adoption) are not yet well known. The dissertation consists of three chapters that aim to assess the impacts of these urban and cluster agglomeration economies' on rural households in Asia."--Excerpted from abstract.
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Title: Revisiting methylotrophy : the impact of lanthanides and lanthanide-dependent enzymes on the methylotrophic metabolic network
Creator: Huff, Anna Frances
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The recent discovery of lanthanide (Ln3+)-dependent enzymes renewed interest in methylotrophs, although the impact of these enzymes is not understood. In Methylobacterium extorquens AM1, the Ca2+ -dependent MxaFI canonically oxidizes methanol to formaldehyde. The tetrahydromethanopterin (H4MPT) pathway oxidizes formaldehyde to formate. Formate is oxidized to CO2 by formate dehydrogenases (FDH) or partially reduced and assimilated. The genome of M. extorquens AM1 codes for three known Ln3+ ...
Show more"The recent discovery of lanthanide (Ln3+)-dependent enzymes renewed interest in methylotrophs, although the impact of these enzymes is not understood. In Methylobacterium extorquens AM1, the Ca2+ -dependent MxaFI canonically oxidizes methanol to formaldehyde. The tetrahydromethanopterin (H4MPT) pathway oxidizes formaldehyde to formate. Formate is oxidized to CO2 by formate dehydrogenases (FDH) or partially reduced and assimilated. The genome of M. extorquens AM1 codes for three known Ln3+ -dependent genes: xoxF, xoxF2, and exaF. XoxF may oxidize both methanol and formaldehyde in some organisms while ExaF demonstrated efficient activity with formaldehyde in the presence of La3+ providing a potential alternative to the H4MPT pathway. RNAseq data provided by Dr. Nathan Good found downregulation of mxa genes and the first gene of the H4MPT pathway, fae, and upregulation of xoxF, xoxF2, and exaF in the presence of La3+ suggesting changes to carbon distribution. I found a sharp decrease in accumulation formaldehyde and fourfold increase in accumulation of formate in the presence of La3+ and hypothesized this was due to the activity of Ln3+ enzymes. I measured the minimum inhibitory concentration (MIC) to methanol metabolism and found decreased sensitivity of a 2206fae mutant from 10 mM to more than 125 mM in the presence of La3+. RNAseq suggested changes to the production of CO2 which I corroborated finding an increased CO2 production of 1.8-fold in the presence of La3+. Together, these data provide the first profile of Ln3+ -dependent methylotrophic metabolism and provides new avenues for research."--Page ii.
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Title: Three dimensional analysis of the gas flow in piston ring pack
Creator: Kharazmi, Ali
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Cylinder-kit dynamics design in an internal combustion engine is highly relevant for the engine performance characteristics, durability and reliability. Since the middle of the 20th century, researchers have been using numerical models to describe the processes that occur in a ring pack. Because it is difficult and extremely costly to conduct experiments on every series of engines to check for the blow-by and oil consumption, a computational analysis can be performed on the ring pack to...
Show more"Cylinder-kit dynamics design in an internal combustion engine is highly relevant for the engine performance characteristics, durability and reliability. Since the middle of the 20th century, researchers have been using numerical models to describe the processes that occur in a ring pack. Because it is difficult and extremely costly to conduct experiments on every series of engines to check for the blow-by and oil consumption, a computational analysis can be performed on the ring pack to study the blow-by and oil-consumption characteristics. In this dissertation a 3D CFD simulation model is introduced to analyze the flow between the cylinder liner and the piston. This model allows for calculation of the piston assembly with consideration of the ring dynamics, transient boundary conditions for combustion chamber pressure and temperature as well as thermal distortion of the piston and liner. The determination of the complex geometry of the cylinder-kit is established in a STL (STereoLithography) format by considering the complicated geometrical details of the ring pack such as thermal distortion of piston and liner, ring twist and ring/groove conformability. The blow by and blow back is numerically calculated for a small bore cylinder operating at 2000 RPM and verified by the results of commercially available 1D models. The calculated velocity filed shows substantial circumferential flow in the piston ring pack that is dominated by the ring and groove geometry as well as the relative position of the rings end gap. It is found that the amount of gas that flows back to the combustion chamber increases when the in-cylinder pressure trace decreases from its peak value. The knowledge from this study can be used as a basis for further multiphase calculations containing oil flow such as oil consumption, oil evaporation and eventually cylinder-kit wear."--Page ii.
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Title: Managing carrot foliar diseases in commercial production fields in Michigan
Creator: Donne, Irene Mariel
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Fungal foliar diseases caused by Alternaria dauci and Cercospora carotae occur annually on carrots. Our goal was to update the disease management tactics by: 1) Testing OMRI-approved and conventional fungicides and 2) Evaluating TOM-CAST. Trials were conducted in 2015 and 2016. Disease severity was visually assessed weekly using the Horsfall-Barratt scale and a petiole health scale; the area under the disease progress curve (AUDPC) was calculated for these parameters. Root yield was...
Show more"Fungal foliar diseases caused by Alternaria dauci and Cercospora carotae occur annually on carrots. Our goal was to update the disease management tactics by: 1) Testing OMRI-approved and conventional fungicides and 2) Evaluating TOM-CAST. Trials were conducted in 2015 and 2016. Disease severity was visually assessed weekly using the Horsfall-Barratt scale and a petiole health scale; the area under the disease progress curve (AUDPC) was calculated for these parameters. Root yield was determined at harvest. Based on AUDPC results obtained in 2015 and 2016, the copperbased fungicides (copper hydroxide and copper hydroxide + copper oxychloride) were the only OMRI-approved products that significantly and consistently limited foliar blight. On the final assessment dates in both years, all conventional fungicides limited foliar and petiole blighting compared to the control with one exception; the propiconazole treatment in 2016 was similar to the control for petiole health. Yields differed significantly among the conventional treatments in 2016 but not in 2015. All treatments yielded significantly higher than the control except for iprodione. Treatments of pyraclostrobin + boscalid, fluxapyroxad + pyraclostrobin, and boscalid had statistically higher yields than penthiopyrad, iprodione, and propiconazole. TOM-CAST 15 and 25 DSV fungicide application schedules effectively reduced foliar blighting in 2015 under relatively light disease pressure. However, the TOM-CAST 25 DSV schedule did not adequately limit disease in 2016 when disease pressure was increased. Recently registered fungicides such as penthiopyrad and fluxapyroxad + pyraclostrobin and using TOM-CAST at the more conservative spray threshold of 15 DSV can help growers limit fungal foliar blight in years with higher disease pressure."--Page ii.
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Title: Defining the characteristics and roles of functional genomic sequences using computational approaches
Creator: Lloyd, John P.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Advances in biotechnology have provided a wealth of sequencing data that is transforming our view of a genome. Eukaryotic genomes, initially thought to contain discrete genes in a sea of non-functional DNA, have been found to exhibit pervasive biochemical activity, particularly transcription. However, whether this biochemical activity is functional (i.e. under evolutionary selection) or the result of noisy activity of cellular machinery represents a fundamental debate of the post-genome era....
Show more"Advances in biotechnology have provided a wealth of sequencing data that is transforming our view of a genome. Eukaryotic genomes, initially thought to contain discrete genes in a sea of non-functional DNA, have been found to exhibit pervasive biochemical activity, particularly transcription. However, whether this biochemical activity is functional (i.e. under evolutionary selection) or the result of noisy activity of cellular machinery represents a fundamental debate of the post-genome era. The research described in this dissertation focuses on two open questions confronting genome biology: 1) Where are the functional elements within a genome? 2) What roles are functional elements performing? For the first question, I focused on transcribed regions in unannotated, intergenic regions of genomes, which represent functionally ambiguous sequences. To determine which and how many intergenic transcribed regions (ITRs) represent functional sequences, machine learning-based function prediction models were established using Arabidopsis thaliana as a model. The prediction models were able to successfully distinguish between benchmark functional (phenotype genes) and non-functional sequences (pseudogenes) using evolutionary, biochemical, and sequence-based structural features. When applied to ITRs, 400303% of ITRs were predicted as functional, suggesting ITRs primarily represent transcriptional noise. I further investigated the evolutionary histories of ITRs in four grass (Poaceae) species. ITRs were found to be primarily species-specific and exhibit recent duplicates, with rare examples of ancient duplicate retention. In addition, ITR duplicates and orthologs were usually not expressed. Function prediction models were also generated in Oryza sativa (rice) that predicted 600303% of rice ITRs as nonfunctional. The results of function prediction models and evaluating evolutionary histories both suggest ITRs are primarily non-functional sequences. However, I also provide a list of potentially-functional ITRs that should be considered high priority targets for future experimental studies. For the second question, I established a machine learning framework to predict mutant phenotypes, which provide potent evidence for the role of a gene. Phenotype predictions were focused on essential genes (those with lethal mutant phenotypes) in A. thaliana, as these genes represent a historically well-studied group. Combining 57 expression, duplication, evolutionary, and gene network characteristics through machine learning methods accurately distinguished between genes with lethal and non-lethal mutant phenotypes. Additionally, essential gene prediction models could be applied across species; essential gene prediction models generated in A. thaliana could identify essential genes in rice and Saccharomyces cerevisiae. Thus, machine-learning represents a promising avenue of prioritization of candidate genes for large-scale phenotyping efforts. Overall, the research described in this dissertation highlight computational approaches as highly effective in defining functional sequences and classifying the likely roles of genes."--Pages ii-iii.
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Title: Mechanistic connections between the proton motive force and ATP homeostasis in higher plant photosynthesis under dynamic environmental conditions
Creator: Carrillo, Leticia Ruby
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Through photosynthesis, plants can capture light energy from the sun for the conversion to a more stable high-energy form, ATP and NADPH. These products are then used to fuel an array of metabolic processes including the biosynthesis of sugars and complex carbohydrates. Yet, the abundant source of solar energy used in the process is highly varied and fluctuates throughout the day, directly impacting the photosynthetic apparatus and carbon assimilation. This dissertation focuses on several...
Show moreThrough photosynthesis, plants can capture light energy from the sun for the conversion to a more stable high-energy form, ATP and NADPH. These products are then used to fuel an array of metabolic processes including the biosynthesis of sugars and complex carbohydrates. Yet, the abundant source of solar energy used in the process is highly varied and fluctuates throughout the day, directly impacting the photosynthetic apparatus and carbon assimilation. This dissertation focuses on several mechanisms by which plants are able to respond to the dynamic environmental pressures through modulation of the proton motive force (pmf) and ATP homeostasis.ATP is the primary energy currency in cells and is synthesized in plastids by the chloroplast ATP synthase. However, unlike other stromal thiol-regulated enzymes that incrementally become redox-activated in response to light, chloroplast ATP synthase acts more like an on-off switch, only requiring minimal irradiance to become fully active. Previous work suggested that the rapid sensitivity to light could be explained by the relative redox potentials of the regulatory thiols on the γ-subunit of ATP synthase. This work uncovered a new, unexpected component, NADPH thioredoxin reductase C (NTRC) that controls thiol regulation specifically under low light intensities. Mutants lacking NTRC show strong photosynthetic phenotypes, e.g., increased nonphotochemical quenching and inhibition of linear electron flow, at low irradiances, consistent with an inability to activate ATP synthase resulting in a buildup of the thylakoid pmf. We predict both NTRC and the canonical ferredoxin-thioredoxin reductase system co-regulate the thiol state of ATP synthase at specific light intensities using different reducing potentials (NADPH versus ferredoxin) that allow for added flexibility.Photosynthesis copes with, and adapts to, fluctuating environments using a wide range of mechanisms. While most of the research has been devoted to the processes occurring inside the plastid, work described here on the nucleotide triphosphate transporter (NTT) illuminates an additional mechanism of augmenting and balancing ATP. Previous work suggested that the chloroplast transporter, NTT, acted primarily as an importer of ATP during the night cycle, presumably under non-photosynthesizing conditions. However, isolated intact chloroplasts from both spinach and Arabidopsis thaliana export ATP at rapid rates that can constitute a large fraction of that generated by the light reactions. Furthermore, these findings suggest that earlier results of minimal rates of ATP transport were based on suboptimal assay conditions and incorrect characterization of T-DNA knockout lines, rendering NTT essential for seed germination. Work on double NTT knock-down lines (NTTdKD) have decreased gene expression levels of ntt1 and ntt2 and show strong photosynthetic responses, particularly in the pH and energy-dependent quenching response (qE) with related accumulation of the pmf under fluctuating light and/or decreased CO2 levels. These results indicate a greater role for NTT in balancing ATP levels between the stromal and cytosolic pools than previously thought.
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Title: Dreams of a soccer city : politics, consumption, and urban transformation in 20th century Buenos Aires
Creator: Galarza, Alex Gabriel
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This dissertation examines the Ciudad Deportiva of Club Atlético Boca Juniors, a massive stadium, sports complex, and leisure site that aimed to redevelop the city’s dilapidated riverfront in the 1960s. The directors of Boca Juniors drew state and municipal support for the Ciudad Deportiva by appealing to developmentalist ideals that prioritized public-private collaborations, consumption, and leisure space for middle class families. As Argentina’s most popular soccer club, hundreds of...
Show moreThis dissertation examines the Ciudad Deportiva of Club Atlético Boca Juniors, a massive stadium, sports complex, and leisure site that aimed to redevelop the city’s dilapidated riverfront in the 1960s. The directors of Boca Juniors drew state and municipal support for the Ciudad Deportiva by appealing to developmentalist ideals that prioritized public-private collaborations, consumption, and leisure space for middle class families. As Argentina’s most popular soccer club, hundreds of thousands of fans and supporters also invested in the project’s fundraising campaign with the belief that Boca’s stadium and facilities would contribute to the city’s modernization and symbolize national progress. Multiple democratic and military governments aided Boca’s efforts throughout a turbulent political and economic period in Argentina’s history, a signal that this kind of mass consumption and family leisure were key concerns for successive, yet divergent, political projects. The club completed most of the original planned facilities by 1970 including various sports fields, an amusement park, an aquarium, a concert pavilion, Argentina’s first drive-in movie theatre, and a social headquarters with a pool and restaurant. However, political infighting at the club, a withdrawal of public and private support, and national economic crises all contributed to Boca’s failure to construct the stadium in time for the 1978 FIFA World Cup. The municipality seized the Ciudad Deportiva in 1979 but over the next thirteen years Boca’s directors were able to regain control of the property and eventually sell it for 22 million dollars. Drawing on newspapers, sports magazines, club documents, and state sources, as well as over twenty oral histories, this dissertation makes two principal arguments. First, that soccer clubs played significant roles in shaping conceptions of neighborhood identity, gender, and class in 20th century Buenos Aires. These institutions did so in tension with their legal status as non-profit civic associations providing services to a membership base while also functioning as producers of the commercialized spectacle of professional soccer. Second, the successes and failures of the Ciudad Deportiva offer a unique perspective through which to consider the very real dreams of development that animated politics in the post-Peronist decades in Argentina. Scholars tend to focus on political polarization and instability, often obscuring the importance of notions about national and urban development embodied in the Ciudad Deportiva.
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Title: Blurring boundaries within mathematics education : prospective K-8 teachers interrogating intersectional identities, narratives, and positionings in out-of-school contexts
Creator: Guzmán, Lynette DeAun
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Mathematics teacher noticing as a pedagogical practice--attending to, interpreting, and responding to children's mathematical thinking--is growing within mathematics education communities. Much of the research literature primarily focuses on supporting teacher noticing of children's mathematical thinking within classroom contexts, such as analyzing classroom artifacts and video recordings. Recent efforts to support teachers make connections between mathematics and children's funds of...
Show more"Mathematics teacher noticing as a pedagogical practice--attending to, interpreting, and responding to children's mathematical thinking--is growing within mathematics education communities. Much of the research literature primarily focuses on supporting teacher noticing of children's mathematical thinking within classroom contexts, such as analyzing classroom artifacts and video recordings. Recent efforts to support teachers make connections between mathematics and children's funds of knowledge, however, often involve professional work outside of classrooms where teachers learn about children's lived experiences and communities. While there is a growing expectation that teachers draw on children's funds of knowledge to support mathematics learning, this kind of professional work requires an ability to notice mathematics in out-of-school contexts. The bulk of this dissertation is written as a series of three interconnected papers from a single qualitative study where I explored activities of a working group I facilitated to support prospective K-8 teachers to notice children's mathematical practices in out-of-school contexts. A primary thread across this work involves blurring boundaries within mathematics education. In my first article (pp. 51-76), I provided an overview of boundary blurring that prospective teachers in this study engaged--between mathematics and people as well as between mathematics and other disciplines--through early field experiences in out-of-school contexts. I zoomed in to examine a specific boundary, women and mathematics, in my second article (pp. 83-105) and explored intersections of gender, age, and elementary mathematics during an interaction at a science museum site visit. Then, in my third article (pp. 110-133), I zoomed out to focus on broader discourses within mathematics education to challenge overly simplistic allor-nothing type stories about mathematics and people (e.g., 'being a math person'). Across my three articles, I engage an overarching question: What stories do prospective teachers tell about themselves, about children, and about mathematics? This study contributes to a collection of stories about prospective teachers' learning to notice children and their mathematical practices with implications for supporting mathematics teacher education, particularly in contexts outside of school. In closing, I share how my work connects to a broader project in mathematics education, blurring boundaries. I pose an underlying question for my continued work: What would it take to decolonize mathematics education?"--Pages ii-iii.
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Title: Remains of Khmer Rouge Violence : the Materiality of Bones as Scientific Evidence and Affective Agents of Memory
Creator: Fleischman, Julie Michele
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The Khmer Rouge regime, led by the infamous Pol Pot, governed Cambodia from 1975 to 1979. Living conditions were severe, and it is estimated that approximately one quarter of the Cambodian population of nearly eight million died from mistreatment, overwork, malnutrition, and violence. Using a biocultural anthropological approach, this research addressed questions concerning individuals executed by the Khmer Rouge regime and the agency (the effect on living individuals) of the resulting...
Show moreThe Khmer Rouge regime, led by the infamous Pol Pot, governed Cambodia from 1975 to 1979. Living conditions were severe, and it is estimated that approximately one quarter of the Cambodian population of nearly eight million died from mistreatment, overwork, malnutrition, and violence. Using a biocultural anthropological approach, this research addressed questions concerning individuals executed by the Khmer Rouge regime and the agency (the effect on living individuals) of the resulting skeletal remains.An osteological analysis of more than 500 crania was conducted at the Choeung Ek Genocidal Center (Choeung Ek) in Phnom Penh. More than 100 original Khmer Rouge execution lists from the detention and torture facility known as S-21—today known as the Tuol Sleng Genocide Museum—were assessed to gather known demographic data for those who were executed and buried at Choeung Ek between 1977 and 1979. To comprehend the incorporation of human skeletal remains from the Khmer Rouge period into the socio-religious framework of modern Cambodia, 13 memorial stupa containing human remains were visited and the caretakers of these memorials were interviewed.The 508 crania at Choeung Ek were assessed for demographic characteristics and traumatic injuries. Results indicate that the majority of crania were estimated to be male (82.9%) and nearly all were of Asian ancestry (86%). The majority of the individuals were young adults (68.3%) between the ages of 20 and 35 years old, although juveniles and older adults were represented. Perimortem trauma was present on 311 crania (61%), with 179 (58%) having discernable impact locations. Blunt force injuries (87%) were the most common mechanism of trauma and the basicranium (53%) was the most frequently impacted region. When the mechanism and location of traumatic injuries were evaluated by sex and age-at-death categories, no statistically significant differences were found indicating that all victims with perimortem trauma were subjected to similar execution methods regardless of their age or sex.At the Tuol Sleng Genocide Museum, 97 definitive Khmer Rouge execution lists were evaluated documenting the murders of 6,285 individuals. The majority (82.1%) were male, the minimum age was 11, the maximum age was 77, and the average age was 29.1 years. When these archival demographic data were compared to these osteologial data, however, there were statistically significant differences between the samples.Observational data from all 13 memorials, and interview data from 10 memorials indicated that the human remains were not formally preserved to prevent decay and there was never a clear indication of how many individuals were represented by the remains with the stupa. The informant’s responses addressed issues such as the identification of the human remains within the memorial, current religious practices conducted at the memorials often in conjunction with caring for the remains, how the remains are displayed for knowledge and/or teaching purposes—although often with a political undertone—and that the memory of the Khmer Rouge period, as well as that of the victims is crucial for modern Cambodians.This research embraced a holistic approach to move beyond the confines of traditional osteological laboratory research by addressing the social impact of the remains. While the Khmer Rouge period was devastating, the human remains of the victims have not been forgotten; the remains continue to remind all who visit that immeasurable violence occurred in Cambodia but also that Cambodians are resilient and they will continue to memorialize those they lost.
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Title: Deep sequencing driven protein engineering : new methods and applications in studying the constraints of functional enzyme evolution
Creator: Wrenbeck, Emily Elizabeth
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Chemical engineers have long sought enzymes as alternatives to traditional chemocatalytic routes as they are highly selective and have evolved to function under mild conditions (physiological temperature, neutral pH, and atmospheric pressure). Enzymes, the workhorses of biological chemistry, represent a vast catalogue of chemical transformations. This feature lends their use in a variety of industrial applications including food processing, biofuels, engineered biosynthetic pathways, and as...
Show more"Chemical engineers have long sought enzymes as alternatives to traditional chemocatalytic routes as they are highly selective and have evolved to function under mild conditions (physiological temperature, neutral pH, and atmospheric pressure). Enzymes, the workhorses of biological chemistry, represent a vast catalogue of chemical transformations. This feature lends their use in a variety of industrial applications including food processing, biofuels, engineered biosynthetic pathways, and as biocatalysts for preparing specialty chemicals (e.g. pharmaceutical building blocks). The totality of an enzymatic bioprocess is a function of its catalytic efficiency (specificity and turnover), product profile (i.e. regio- and enantio-selectivity), and thermodynamic and kinetic stability. For native enzymes, these parameters are seldom optimal. Importantly, they can be modified using protein engineering techniques, which generally involves introducing mutation(s) to a protein sequence and screening for beneficial effects. However, robust enzyme engineering and design based on first principles is extremely challenging, as mutations that improve one parameter often yield undesired tradeoffs with one or more other parameters. In this thesis, deep mutational scanning - the testing of all possible single-amino acid substitutions of a protein sequence using high-throughput screens/selections and DNA counting via deep sequencing - was used to address two fundamental constraints on functional enzyme evolution. First, how do enzymes encode substrate specificity? To address this question, deep mutational scanning of an amidase on multiple substrates was performed using growth-based selections. Comparison of the resulting datasets revealed that mutations benefiting function on a given substrate were globally distributed in both protein sequence and structure. Additionally, our massive datasets permitted the most rigorous testing to date of theoretical models of adaptive molecular evolution. These results have implications for both design of biocatalysts and in understanding how natural enzymes function and evolve. Another fundamental constraint of enzyme engineering is that mutations improving stability (folding probability) of an enzyme are often inactivating for catalytic function, and vice versa. Towards overcoming this activity-stability constraint, I sought to improve the heterologous expression and maintain the catalytic function of a Type III polyketide synthase from Atropa belladonna. This was accomplished using deep mutational scanning and high-throughput GFP-fusion stability screening, followed by novel filtering methods to only accept beneficial mutations with high probability for maintaining function. Lastly, deep mutational scanning relies on the construction of user-defined DNA libraries, however current available techniques are limited by accessibility or poor coverage. To address these limitations, I will present the development of Nicking Mutagenesis, a new method for the construction of comprehensive single-site saturation mutagenesis libraries that requires only double-stranded plasmid DNA as input substrate. This method has been validated on several gene targets and plasmids and is currently being used in academic, government, and industry laboratories worldwide."--Pages ii-iii.
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Title: Freshwater resources : an evaluation of Michigan residents' perception of wetland ecosystem services
Creator: Walkowiak, Toni Anne
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Thus, this research serves two purposes: (1), to gather information about Michigan residents' overall knowledge of wetlands ecosystems; (2), to establish whether residents can accurately distinguish between wetland functions and values. Two activities: semi-structured focus group interviews and online digital card sorts were conducted within Chippewa, Huron, and Macomb Counties of Michigan, to evaluate individuals' environmental perceptions of wetland ecosystems." -- Abstract.

Title: Local food in perspective : place, time, authenticity, and the relocalization of the food system
Creator: Giorda, Erica
Date: 2017
Collection: Electronic Theses & Dissertations
Description: While the research on local food systems and movements is well established, the time related aspects of local food promotion, production, and consumption have been barely explored.This dissertation starts to address that topic through three articles: a theoretical analysis of time and agency in food relocalization processes, and two case studies that address ideas of authenticity and heritage, community ties, and place making practices based on the selective framing of shared temporalities at...
Show moreWhile the research on local food systems and movements is well established, the time related aspects of local food promotion, production, and consumption have been barely explored.This dissertation starts to address that topic through three articles: a theoretical analysis of time and agency in food relocalization processes, and two case studies that address ideas of authenticity and heritage, community ties, and place making practices based on the selective framing of shared temporalities at Eastern Market in Detroit.First, I use French Convention Theory to examine how a set of vendors at Eastern Market in Detroit sell their food emphasizing craftsmanship and cultural values more than price or provenance. The work of these vendors manifests a form of compromise between the Domestic and Market worlds that is based on reputation and regard. This shifts the meaning of local food from provenance to a form of authenticity based on the presentation of heritage and community ties.Second, I investigate the ways local actors use the physical arrangements of the space inside and around the Market and how the promotion of local food through new and old references to craftsmanship, care and tradition contribute to the creation of a sense of place. Following Gieryn and Molotch et al., place-making is presented as a recursive process led by ‘strategically placed actors’ (Giddens 1984) whose action creates a conceptual narrative that may create exclusionary spaces. I adopt a visual approach to offer a fresh perspective in terms of understanding the intersection of time and space, history and geography, as well as clarifying how ideas of locality and place are performed.Third, I analyze embeddedness as pertinent to local food systems, from the perspective of time. Drawing from ethnographic research and current literature I highlight the different ways in which time is a relevant variable that makes food embedded in social systems and reduces the alienating effects of the commodification of the food chain. Appeals to tradition, history, ancestry, duration, co-presence and time commitment are different time-related aspects that support the embedding of food production, preparation, and consumption. This approach also allows for identifying agency in wider sets of actions and behaviors than looking at spatial patterns only.The three papers together contribute to increasing the understanding and theorization of place making processes, the relevance of seemingly marginal practices with respect to the determination of agency, and to increasing the focus on the temporal gaze in relation to commodification and de-commodification practices in the areas of local food production and consumption.
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Title: Voices of Mayan Women in Plaza Comunitaria : poetica y educacion desde Yucatan
Creator: Ceballos Zapata, Abraham
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This study took place in a village in Yucatan, Mexico in the context of two adult education programs in Yucatan [Plaza Comunitaria and Preparatoria Abierta]. I interacted in convivencia with bilingual (Mayan-Spanish) Yucatec Mayan women who took on the challenge of completing their formal schooling through those adult education programs. Over 3 summers (2013, 2014, 2015) I immersed myself in the community and witnessed their educational efforts. Ethnographic and convivencia methodologies ...
Show moreThis study took place in a village in Yucatan, Mexico in the context of two adult education programs in Yucatan [Plaza Comunitaria and Preparatoria Abierta]. I interacted in convivencia with bilingual (Mayan-Spanish) Yucatec Mayan women who took on the challenge of completing their formal schooling through those adult education programs. Over 3 summers (2013, 2014, 2015) I immersed myself in the community and witnessed their educational efforts. Ethnographic and convivencia methodologies (Galvan, 2015) helped generate data. I analyzed data with methodologies stemming from the humanities, in narrative (Clandinin & Connelly, 2004) and poetic analysis (Görlich, 2016; Prendergast, Leggo, & Sameshima, 2009). Through my discussion, I explore how the efforts of Yucatec Mayan women prompt educators imagine possibilities for decolonial education and inform our pedagogical practices across multiple educational settings. By focusing on the voices of rural women as poetry, I evoke the rhythms and memories of their lives in indigenous communities and in educational settings. This emerging research has taught me life and professional lessons of education on the margins. I witnessed their ethos of familia, and solidaridad as they studied together. Most importantly, they showed me how studying and being in community are inseparable. -- Abstract.
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