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- Title
- Online innovization : towards knowledge discovery and achieving faster convergence in multi-objective optimization
- Creator
- Gaur, Abhinav
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
-
Ì0300nnovization'' is a task of learning common principles thatexist among some or all of the Pareto-optimal solutions in amulti-objective optimization problem. Except a few earlierstudies, most innovization related studies were performed onthe final non-dominated solutions found by an evolutionary multi-objective algorithm eithermanually or by using a machine learning method.Recent studies have shown that these principles can be learnedduring intermediate iterations of an optimization run...
Show moreÌ0300nnovization'' is a task of learning common principles thatexist among some or all of the Pareto-optimal solutions in amulti-objective optimization problem. Except a few earlierstudies, most innovization related studies were performed onthe final non-dominated solutions found by an evolutionary multi-objective algorithm eithermanually or by using a machine learning method.Recent studies have shown that these principles can be learnedduring intermediate iterations of an optimization run and simultaneously utilized in thesame optimization run to repair variables to achieve a fasterconvergence to the Pareto-optimal set. This is what we are calling as ò0300nline innovization'' as it is performed online during the run of an evolutionary multi-objective optimization algorithm. Special attention is paid to learning rules that are easier to interpret, such as short algebraic expressions, instead of complex decision trees or kernel based black box rules.We begin by showing how to learn fixed form rules that are encountered frequently in multi-objective optimization problems. We also show how can we learn free form rules, that are linear combination of non-linear terms, using a custom genetic programming algorithm. We show how can we use the concept of k0300nee' in PO set of solutions along with a custom dimensional penalty calculator to discard rules that may be overly complex, or inaccurate or just dimensionally incorrect. The results of rules learned using this custom genetic programming algorithm show that it is beneficial to let evolution learn the structure of rules while the constituent weights should be learned using some classical learning algorithm such as linear regression or linear support vector machines. When the rules are implicit functions of the problem variables, we use a computationally inexpensive way of repairing the variables by turning the problem of repairing the variable into a single variable golden section search.We show the proof of concept on test problems by learning fixed form rules among variables of the problem, which we then use during the same optimization run to repair variables. Different principleslearned during an optimization run can involve differentnumber of variables and/or variables that arecommon among a number of principles. Moreover, a preferenceorder for repairing variables may play an important role forproper convergence. Thus, when multiple principles exist, itis important to use a strategy that is most beneficial forrepairing evolving population of solutions.The above methods are applied to a mix of test problems and engineering design problems. The results are encouraging and strongly supportsthe use of innovization task in enhancing the convergence of an evolutionary multi-objective optimization algorithms. Moreover, the custom genetic program developed in this work can be a useful machine learning tool for practitioners to learn human interpretable rules in the form of algebraic expressions.
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- Title
- "My life is changed but the trust ain't there to trust somebody else" : experiences of recovery from intimate partner abuse of women of Mexican heritage in a mid-size city in Michigan
- Creator
- Palma-Ramirez, Evangelina
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
-
This exploratory qualitative study aimed to gain an understanding of the experiences of recovery from intimate partner abuse (IPA) of 17 women of Mexican heritage in a mid-size urban city in Michigan. IPA was defined as any type of physical, sexual, stalking, psychological harm or coercive control by a former intimate partner or spouse. Two aspects were explored: experiences of abuse and experiences of recovery from abuse. The study used a feminist theory and intersectionality perspective as...
Show moreThis exploratory qualitative study aimed to gain an understanding of the experiences of recovery from intimate partner abuse (IPA) of 17 women of Mexican heritage in a mid-size urban city in Michigan. IPA was defined as any type of physical, sexual, stalking, psychological harm or coercive control by a former intimate partner or spouse. Two aspects were explored: experiences of abuse and experiences of recovery from abuse. The study used a feminist theory and intersectionality perspective as a guiding framework to understand the experiences of women considering their contextual situation. Data were collected using a semi-structured questionnaire and analyzed using a constructivist grounded theory by Charmaz. The findings revealed that women understand their experiences of abuse as being connected to their early socialization about gender roles, history of child abuse, lack of sexual education, and the influence of the environment. Also, the participants revealed they experienced overlapping types of abuse: psychological, coercion, economic, physical, sexual, and stalking. Despite the negative impact of the abuse on participants' physical and mental health, findings showed that women were able to recover from the abuse and to move on with their lives. Data suggested that the recovery was a gradual ongoing process of physical and psychological healing. Participants identified empowering experiences that helped them in their recovery from IPA. Such empowering experiences included life-changing religious realizations, receiving services in Spanish, acquiring more education, receiving counseling services, and getting a job. Receiving social support from family and friends and having access to resources were identified as factors that aided in the recovery from IPA. However, some participants experienced limited access to such resources due to economic constraints, cultural beliefs about gender roles, and the impact of immigration policies.Lastly, findings revealed that experiences of recovery from IPA vary based on whether women decided to leave their partners or to remain with them. Implications for culturally sensitive interventions for Latinas of Mexican heritage are discussed as well as implications for future research on issues of recovery for this specific Latino subgroup.
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- Title
- ER stress sensor IRE1-alpha and its implications in progression of hepatocellular carcinoma
- Creator
- Oak, Amrita
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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"The endoplasmic reticulum (ER) is the site for protein folding and maturation. ER stressors, both physiological and pharmacological, can result in activation of the unfolded protein response (UPR). Palmitate, a saturated fatty acid, is one such ER stressor and leads to induction of the UPR. This is primarily through the activation of Inositol Requiring Enzyme-1 (IRE1) leading to splicing of XBP1 mRNA. However, the mechanism of this activation is unclear. With the aid of a bimolecular...
Show more"The endoplasmic reticulum (ER) is the site for protein folding and maturation. ER stressors, both physiological and pharmacological, can result in activation of the unfolded protein response (UPR). Palmitate, a saturated fatty acid, is one such ER stressor and leads to induction of the UPR. This is primarily through the activation of Inositol Requiring Enzyme-1 (IRE1) leading to splicing of XBP1 mRNA. However, the mechanism of this activation is unclear. With the aid of a bimolecular fluorescence complementation (BiFC) assay, we identified two crucial residues on the transmembrane domain (TM) of IRE1, S450 and W457, that are drivers of palmitate mediated activation. Previous research from our group suggested that IRE1 also has binding sites for palmitate on its cytosolic domain (CD). However, IRE1-CD protein expressed in E. coli was over-phosphorylated which possibly affected its binding to PA. To investigate this, we developed a protocol for expression and purification of wild type and mutant IRE1-CD protein in insect Sf21 cells. A fluorescence polarization based binding assay was performed to determine whether palmitate binds to residues on the IRE1-CD protein. Previously our laboratory demonstrated that palmitate induced the migration of cancer cells as well as transcription factors (TF) involved in epithelial-to-mesenchymal transition (EMT). Here, we investigated the role of IRE1 activation on these processes. Using CRISPR gene editing to generate IRE1 knockouts in liver and breast cancer cell lines, we observed that IRE1 mediates the upregulation in EMT-TFs, a decrease in the expression of the desmoplakin (DSP) protein, and an increase in the migration of liver and breast cancer cells. DSP is a critical component of desmosomes, which function to maintain the structural integrity at adjacent cell-cell contacts.In addition to migration, the effect of XBP1 splicing on metabolism has not been studied. We found the activation of IRE1-XBP1 is accompanied by changes in the metabolic genes involved in glycolysis, fatty acid oxidation, gluconeogenesis, and ceramide metabolism, suggesting that some of the metabolic effects of palmitate are mediated through IRE1. These results could have implications on the development of chemotherapeutic strategies. This study paves the way for further investigations into the far-reaching effects of activation of the UPR on cell survival, metabolism, and chemo-tolerance."--Pages ii-iii.
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- Title
- Analysis of the petrology and geochemistry of the magmas of the Galema range in the Somalian Plateau, Ethiopia : a probe of lithospheric processes of the northern east African rift system
- Creator
- Chiasera, Brandon
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
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As a continental rift evolves towards a mid ocean ridge, the continental lithosphere must rupture and extension must become accommodated exclusively by seafloor spreading. During this process, extensional strain is initially accommodated along the nascent rift margins, subsequently localizing to zones of focused magmatic intrusion. Asthenospheric conditions such as increased mantle potential temperature or presence of an upwelling, deep seated mantle anomaly may influence, or be responsible...
Show moreAs a continental rift evolves towards a mid ocean ridge, the continental lithosphere must rupture and extension must become accommodated exclusively by seafloor spreading. During this process, extensional strain is initially accommodated along the nascent rift margins, subsequently localizing to zones of focused magmatic intrusion. Asthenospheric conditions such as increased mantle potential temperature or presence of an upwelling, deep seated mantle anomaly may influence, or be responsible for, these extensional processes. While these processes are integral in the process of continental rifting, how they relate and influence each other remains an area of active scientific inquiry and debate. The Main Ethiopian Rift (MER) in East Africa is the ideal location to study extensional processes. We examine the Galema range, an area of focused magmatic activity along the eastern margin of the Central Main Ethiopian Rift, which is morphologically similar to areas of focused magmatism within the rift. To better understand the complex processes involved in continental rifting and how they are related, we present whole-rock, major and trace element data on 77 samples of the Galema range magmas, including isotopic geochemistry on 22 of these samples. We find that whole rock thermodynamic modeling and thermobarometric calculations on mineral-liquid pairs suggest that fractionation (and hence magma stalling depths) within the Galema range is polybaric (70303 and 30303 kbar). These results, when compared to zones of focused intrusion within the rift, indicate an incipient magmatic plumbing system. Trace element models of melt generation reveal melting conditions of 1418-1450°C at 2.9-3.2 GPa. These conditions reveal that Ethiopian mantle TP is elevated by 603038-100°C over ambient. In contrast, Si/Mg activity thermobarometry, which probes the point at which these magmas last re-equilibrated with the mantle, yielded broadly similar temperatures (1435-1474°C) but at lower pressures (2.1-2.6 ± 0.2 GPa). We interpret these results as evidence for magma stalling at a thermo-mechanical boundary to ascent, which we contend is the lithosphere-asthenosphere boundary (LAB). Isotopic analyses of the magmas of the Galema range indicate the presence of signatures of the Afar plume, Pan-African lithosphere, and depleted mantle. A subset of these isotopic analyses indicates the presence of a previously unknown, 4th mantle end member, which we attribute to be a contribution from a recently created, and destroyed, sub-continental lithosphere beneath the eastern Ethiopian plateau. We contend that diking associated with the Galema range, which pre-dates magmatic belts within the rift; thermomechanically modified the lithosphere along this margin. The thermomechanical modification of the lithosphere mantle along this margin facilitated the subsequent development of within-rift magmatic chains. The implications of this are that off-rift magmatic activity may play an integral role in facilitating the development of rift architecture. We interpret contrasting results between two trace element modeling approaches as evidence for magma ponding subsequent to melt generation. While the continental lithosphere has thinned during extension, the lithosphere remains relatively thick late into the rifting process, despite the development of magmatic extension at crustal depths. The presence of an isotopic signature of a sub-continental lithospheric mantle indicates rapid creation and destruction of lithospheric material in processes attributed to the upwelling Afar plume. This process may be one way in which the lithosphere is thinned in the EARS, along with foundering and assimilation of material into the depleted asthenosphere.
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- Title
- Fluid reasoning as a predictor of deviant workplace behaviors
- Creator
- Matusik, James Garrett
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
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Relative to the sizable body of work investigating the relationship between intelligence and task performance, one facet of overall job performance, very little research has been conducted on the relationship between intelligence and counterproductive work behavior, a different but equally important facet of job performance. Furthermore, the little research that has been conducted on the intelligence-counterproductive work behavior relationship has yielded entirely inconsistent results -...
Show moreRelative to the sizable body of work investigating the relationship between intelligence and task performance, one facet of overall job performance, very little research has been conducted on the relationship between intelligence and counterproductive work behavior, a different but equally important facet of job performance. Furthermore, the little research that has been conducted on the intelligence-counterproductive work behavior relationship has yielded entirely inconsistent results - while some researchers have found a negative relationship between intelligence and counterproductive work behavior, others have found null or positive relationships. This, coupled with the reality that none of these studies have explicitly tested causal mechanisms, provides us with an entirely unclear understanding of this relationship. Thus, the goal of this dissertation is to more carefully examine the potential relationship(s) between intelligence and counterproductive work behavior by (a) capturing both overt and covert counterproductive work behaviors, (b) testing a previously identified, but thus far untested, mediating mechanism, and (c) incorporating moderators, selected based upon criminology research that has leveraged a psychological approach in the explanation of individual deviance.
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- Title
- The role of affect in binge eating phenotypes : an examination of individual differences in emotion experience and interactions with ovarian hormones
- Creator
- Mikhail, Megan Elizabeth
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
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Ovarian hormones significantly influence dysregulated eating in females. However, most women do not develop appreciable disordered eating, suggesting that ovarian hormones may not affect all women equally. In the first study of this thesis, I examined whether individual differences in trait negative affect (NA) moderate ovarian hormone-dysregulated eating associations in 446 women who provided saliva samples for hormone measurements and ratings of NA and emotional eating daily for 45...
Show moreOvarian hormones significantly influence dysregulated eating in females. However, most women do not develop appreciable disordered eating, suggesting that ovarian hormones may not affect all women equally. In the first study of this thesis, I examined whether individual differences in trait negative affect (NA) moderate ovarian hormone-dysregulated eating associations in 446 women who provided saliva samples for hormone measurements and ratings of NA and emotional eating daily for 45 consecutive days. Women were at greatest risk for emotional eating when they had high trait NA and experienced a hormonal milieu characterized by low estradiol or high progesterone. While effects were significant in all women, the combination of high trait NA and high progesterone was particularly risky for women with a history of clinically significant binge eating episodes. These findings provide initial evidence that affective and hormonal risk interact to promote dysregulated eating, and that effects may be amplified in women with clinically significant binge eating.Low emotion differentiation (the tendency to experience vague affective states rather than discrete emotions) is associated with psychopathology marked by emotion regulation deficits and impulsive/maladaptive behavior. However, research examining associations between emotion differentiation and dysregulated eating is still nascent. In the second study, I therefore examined associations between several measures of emotion differentiation and binge eating phenotypes across a spectrum of severity.
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- Title
- Barriers and facilitators to the utilization of the ACT SMART implementation toolkit in community agencies : a qualitative study
- Creator
- Sridhar, Aksheya
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
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Evidence-based practices (EBPs) have been shown to improve outcomes for children diagnosed with autism spectrum disorder (ASD; Wong et al., 2015). Research suggests that the utilization of these practices in community settings is varied (Paynter & Keen, 2015; Pickard, Meza, Drahota, & Brikho, 2018); however, the utilization of implementation guides may bridge the gap between research and practice (Drahota et al., 2017). The Autism Community Toolkit: Systems to Measure and Adopt Research-Based...
Show moreEvidence-based practices (EBPs) have been shown to improve outcomes for children diagnosed with autism spectrum disorder (ASD; Wong et al., 2015). Research suggests that the utilization of these practices in community settings is varied (Paynter & Keen, 2015; Pickard, Meza, Drahota, & Brikho, 2018); however, the utilization of implementation guides may bridge the gap between research and practice (Drahota et al., 2017). The Autism Community Toolkit: Systems to Measure and Adopt Research-Based Treatments (ACT SMART Toolkit; Drahota, Meza, & Martinez, 2014) is a web-based implementation toolkit developed to guide ASD implementation teams through the phases of EBP implementation in community agencies. This study examined the barriers and facilitators (collectively termed "determinants") to the utilization of this toolkit, based on the perspectives of implementation teams at six ASD community agencies. Two independent coders utilized the adapted EPIS model (Drahota et al., 2017; Moulin et al., 2019) and the Technology Acceptance Model 3 (Venkatesh & Bala, 2008), to guide thematic analyses of participant interviews. Salient determinants were identified, and analyses highlighted two themes: (a) Inner Context Determinants to use of the toolkit (e.g., funding), and (b) Innovation Determinants (e.g., facilitation teams). Finally, determinants that differed across adapted EPIS phases of the toolkit were identified. Findings highlight areas of improvement for the ACT SMART Implementation Toolkit, as well as factors to facilitate the use of this implementation guide. Additionally, findings may inform the development, refinement, and utilization of implementation guides with the aim of increasing the uptake of evidence-based practices in community agencies providing services to children with autism spectrum disorder.
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- Title
- From sitting to living : examining the role of meditation in understanding the emotion regulatory mechanisms of mindfulness
- Creator
- Lin, Yanli
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
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Mindfulness has received widespread interest for its purported benefits to emotional well-being. Despite a rapidly growing literature base supporting the salutary relationship between mindfulness and emotion regulation, little is known about how mindfulness confers its emotion regulatory benefits. A pertinent, yet underexplored, approach to addressing this question is to examine neural mechanisms involved in the effects of mindfulness training via meditative practice to "off-the-cushion"...
Show moreMindfulness has received widespread interest for its purported benefits to emotional well-being. Despite a rapidly growing literature base supporting the salutary relationship between mindfulness and emotion regulation, little is known about how mindfulness confers its emotion regulatory benefits. A pertinent, yet underexplored, approach to addressing this question is to examine neural mechanisms involved in the effects of mindfulness training via meditative practice to "off-the-cushion" changes in emotion regulation. The primary aim of the present study was therefore to determine the extent to which change in neural oscillatory activity (i.e., alpha and theta power) during mindfulness meditation related to subjective (i.e., self-reported negative affect) and neural (i.e., late positive potential [LPP]) measures of emotional reactivity elicited during a subsequent affective picture viewing task. Toward this end, a multimodal experimental paradigm was employed to test three predictions: 1) participants randomized to engage in brief guided mindfulness meditation, relative to those randomized to a control condition, would exhibit increased alpha and theta power during meditation relative to rest; 2) participants in the meditation group, but not those in the control group, would exhibit attenuated LPP responses and report lower negative affect during the picture viewing task; 3) the predicted increases in alpha and theta power during meditation would correlate with the predicted reductions in the LPP and self-reported negative affect during picture viewing. Contrary to expectations, the guided meditation did not produce demonstrable effects on alpha and theta power, the LPP, or self-reported negative affect relative to the control condition. Change in theta, but not alpha, power during meditation was, however, positively correlated with the early time window of the LPP, suggesting that change in neural activity during meditation may relate to subsequent emotion processing. Overall, the study demonstrated the utility of investigating the relationship between what occurs during mindfulness meditation and its purported effects on emotion regulation. Moreover, reflections on the unexpected nature of the null findings dovetail with the prevailing consensus that theoretical and methodological factors unique to the construct of mindfulness are integral in shaping the direction, design, and interpretability of mindfulness research.
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- Title
- Turkish teachers and imams and the making of Turkish German difference
- Creator
- Van Wyck, Brian
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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This dissertation investigates the intersections of education, Islam, and knowledge production in the history of postwar migration to West Germany. It focuses on how Germans and Turks grappled with the permanent presence of Turkish guest workers, refugees, and their families in the Federal Republic of Germany (FRG) from the 1960s onward. To understand how ideas about this population of Turkish Germans shaped notions of race, culture, and belonging in both countries, two surprisingly under...
Show moreThis dissertation investigates the intersections of education, Islam, and knowledge production in the history of postwar migration to West Germany. It focuses on how Germans and Turks grappled with the permanent presence of Turkish guest workers, refugees, and their families in the Federal Republic of Germany (FRG) from the 1960s onward. To understand how ideas about this population of Turkish Germans shaped notions of race, culture, and belonging in both countries, two surprisingly under-researched groups are used as a lens: Turkish teachers and imams. Both were charged with seeing to the educational and spiritual needs of what was West Germany's largest immigrant population by 1973. As such, policies, practices, and debates surrounding the hiring, supervision, and activities of relatively small numbers of teachers and imams offer insight into what a broad spectrum of state and civil society stakeholders in both countries believed they knew about Turkish Germans, what differentiated them from the German majority or Turks in Turkey proper, and what interventions were made necessary by that difference. Teachers and imams were simultaneously actors producing knowledge about Turks in the FRG for audiences in both countries, agents tasked with carrying out interventions at the behest of various stakeholders on the basis of this knowledge, and, as Turkish Germans, were themselves subjects of this knowledge regime. As such, they reveal the complicated dynamics underlying why and how what was known about Turkish German difference changed over time. This in turn identifies shifts in ideas about the nation, race, and Islam in Turkey and Germany.Comparing teachers and imams and using sources in Turkish and German as diverse as theater, poetry, oral history, diplomatic correspondence, and the academic and popular press, this dissertation breaks with several common scholarly and popular assumptions. First, it demonstrates the contingency of the emergence in the 1980s of Islam as the most salient aspect of Turkish difference and an essential element of Turkish national identity, rather than a marker of membership in the broader, international "Muslim world." The project identifies the centrality of Islam to the racialization of Turkish difference and the role of Turkish expertise in this process of essentialization. Second, the comparison between teachers and imams highlights the contextual nature of the construction of this essential difference. Even as imams were positioned as experts with proprietary knowledge of Turkish Islam, Turkish teachers lost their privileged status and their cultural and linguistic knowledge was increasingly understood as backwards and irrelevant in the context of the universalistic German school. Thus, Turkish difference in German schools was perceived differently than when it was imagined in a mosque or Koran course. The dissertation offers an account of the development and implications of this interplay between belonging and exclusion, and knowledge and ignorance. This allows it to complicate previous literature which has located German policies and attitudes toward foreigners in the legacies of the Third Reich or in an unchanging and particularly German ethnoracial conception of the nation.
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- Title
- Examining dynamic interpersonal processes associated with alliance rupture in psychotherapy
- Creator
- Luo, Xiaochen
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
-
Alliance ruptures refer to tensions and negative processes between therapist and patient. Identifying ruptures is important because research shows that ruptures play an important role in establishing therapeutic alliance and in promoting therapeutic changes. However, previous studies have not used within-person methodology to explore the dynamic and dyadic processes of interpersonal behaviors in ruptures and thus there is little evidence to guide clinicians in the identification of ruptures....
Show moreAlliance ruptures refer to tensions and negative processes between therapist and patient. Identifying ruptures is important because research shows that ruptures play an important role in establishing therapeutic alliance and in promoting therapeutic changes. However, previous studies have not used within-person methodology to explore the dynamic and dyadic processes of interpersonal behaviors in ruptures and thus there is little evidence to guide clinicians in the identification of ruptures. The current study utilizes an intensive single-case analytic approach to examine how patients' and therapists' dominance, warmth, and interpersonal complementarity are associated with in-session confrontation ruptures and withdrawal ruptures in sixteen adult psychotherapy sessions from eight independent therapeutic dyads. Interpersonal behaviors and ruptures were coded and processed at a half-minute interval. Dynamic factor analysis models were fit to examine the relationships between interpersonal variables and ruptures for each single session. Generalizability was examined by comparing results within dyads and across dyads. Patient's increased cold or dominant behaviors, as well as the dyad's increased dominance complementarity, were related with confrontation ruptures in more than one third of the sessions. Therapist's decreased dominant behaviors and patient's increased dominant behaviors were related with withdrawal ruptures in more than one third of the sessions. The results also identified dyad- and session-specific patterns that did not generalize across cases but may be of clinical interest. These findings highlight the important roles of both therapists' and patients' behaviors as well as their synchronization on dominance in the development of alliance ruptures, extended our knowledge on within-person interpersonal dynamics associated with ruptures, and emphasized the need to examine both idiographic and nomothetic processes of alliance ruptures.
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- Title
- A container-attachable inertial sensor for real-time hydration tracking
- Creator
- Griffith, Henry
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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The underconsumption of fluid is associated with multiple adverse health outcomes, including reduced cognitive function, obesity, and cancer. To aid individuals in maintaining adequate hydration, numerous sensing architectures for tracking fluid intake have been proposed. Amongst the various approaches considered, container-attachable inertial sensors offer a non-wearable solution capable of estimating aggregate consumption across multiple drinking containers. The research described herein...
Show moreThe underconsumption of fluid is associated with multiple adverse health outcomes, including reduced cognitive function, obesity, and cancer. To aid individuals in maintaining adequate hydration, numerous sensing architectures for tracking fluid intake have been proposed. Amongst the various approaches considered, container-attachable inertial sensors offer a non-wearable solution capable of estimating aggregate consumption across multiple drinking containers. The research described herein demonstrates techniques for improving the performance of these devices.A novel sip detection algorithm designed to accommodate the variable duration and sparse occurrence of drinking events is presented at the beginning of this dissertation. The proposed technique identifies drinks using a two-stage segmentation and classification framework. Segmentation is performed using a dynamic partitioning algorithm which spots the characteristic inclination pattern of the container during drinking. Candidate drinks are then distinguished from handling activities with similar motion patterns using a support vector machine classifier. The algorithm is demonstrated to improve true positive detection rate from 75.1% to 98.8% versus a benchmark approach employing static segmentation. Multiple strategies for improving drink volume estimation performance are demonstrated in the latter portion of this dissertation. Proposed techniques are verified through a large-scale data collection consisting of 1,908 drinks consumed by 84 individuals over 159 trials. Support vector machine regression models are shown to improve per-drink estimation accuracy versus the prior state-of-the-art for a single inertial sensor, with mean absolute percentage error reduced by 11.1%. Aggregate consumption accuracy is also improved versus previously reported results for a container-attachable device.An approach for computing aggregate consumption using fill level estimates is also demonstrated. Fill level estimates are shown to exhibit superior accuracy with reduced inter-subject variance versus volume models. A heuristic fusion technique for further improving these estimates is also introduced herein. Heuristic fusion is shown to reduce root mean square error versus direct estimates by over 30%. The dissertation concludes by demonstrating the ability of the sensor to operate across multiple containers.
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- Title
- Willingness to pay for processed grains in Dakar, Senegal : an analysis using discrete choice experiments
- Creator
- Chase-Walsh, Sarah Victoria
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
-
This article studies consumer preference for processed traditional and non-traditional grains in Dakar, Senegal. While much attention has focused on substitution between traditional and nontraditional grains, less has shown how consumers make tradeoffs among processed products. Using an exit-interview method and two discrete choice experiments, I obtain marginal values of willingness to pay for processed grains. In this paper, I measure willingness to pay for domestically produced millet,...
Show moreThis article studies consumer preference for processed traditional and non-traditional grains in Dakar, Senegal. While much attention has focused on substitution between traditional and nontraditional grains, less has shown how consumers make tradeoffs among processed products. Using an exit-interview method and two discrete choice experiments, I obtain marginal values of willingness to pay for processed grains. In this paper, I measure willingness to pay for domestically produced millet, maize, rice, and sorghum. I also measure willingness to pay for a second stage processed millet product. The results of this study show that consumers are willing to pay a premium for domestically produced processed grains, both traditional and non-traditional, save sorghum. Consumers are only willing to pay a positive premium for imported rice. The results also suggest that consumers are willing to pay a premium for fresh and bulk second stage processed millet.
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- Title
- Quantifying impacts of anthropogenic disturbances on wildlife
- Creator
- Mudumba, Tutilo
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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In this dissertation, I examined the interconnectedness of human population growth, energy development, human-wildlife coexistence, and wildlife population ecology. In Chapter One, I reviewed the literature and categorized the effects of oil extraction on wildlife. Broadly, the effects included: i) increased poaching, ii) curtailed space-use, iii) increased harassment, iv) risk of introduction of invasive species, v) contamination, and vi) heightened the severity of impacts due to synergistic...
Show moreIn this dissertation, I examined the interconnectedness of human population growth, energy development, human-wildlife coexistence, and wildlife population ecology. In Chapter One, I reviewed the literature and categorized the effects of oil extraction on wildlife. Broadly, the effects included: i) increased poaching, ii) curtailed space-use, iii) increased harassment, iv) risk of introduction of invasive species, v) contamination, and vi) heightened the severity of impacts due to synergistic effects. Overall, I found that efforts to evaluate the consequences of oil extraction, particularly in peer-reviewed form, were limited. Research should be conducted pre-, during, and post-oil extraction to increase knowledge of the effects of oil extraction on wildlife to enable more effective policy decisions.In Chapter Two, I studied human-wildlife co-existence and found that conflict was the most important factor determining local people's attitude towards poaching. Less than 20% of the local people had ever visited the park and there was limited flow of benefits for local communities from protected areas. My findings highlight the importance of providing remedies compatible with local livelihoods and could be used to improve wildlife management to address poaching.In Chapter Three, I predicted the African lion (Panthera leo) carrying capacity in Murchison Falls National Park (MFNP) from existing primary prey biomass. I found that the extant African lion density was four times less than what the prey biomass inside the park could support. I compared the African lion density estimated from prey biomass to that estimated from direct counts and found that estimating lion density from indirect methods such as prey biomass can result in the overestimation of existent populations.In Chapter Four, I described an approach for estimating the density, configuration, and lethality of poacher-set snares and discussed their effects on wildlife inside MFNP. Murchison Falls National Park had the highest known density of wire snares in the world. I provide a litany of anthropogenic and environmental configurations that made snares more likely to catch an animal. The ability of snares to trap an animal were significantly predicted by snare thickness, noose width, vertical drop, wire circumference, grass height, and anchor tree diameter at breast height. Regulating the disposal of dis-used vehicle tires which provided the material for the wire snares was likely to reduce snare poaching inside the park. Additionally, providing alternative livelihoods to people involved in snare poaching would discourage the recruitment of locals in snare poaching. My method of surveying snares provides the opportunity to standardize temporal and spatial measurements of snare density and configuration as a first step to refine mitigation techniques.I conclude my dissertation with a summary of my key findings and recommendations for future research. The results of my research are applicable to biodiverse-rich portions of the world that are at risk of human development. My methods could also be used to quantify the severity of subsistence poaching. This is relevant because subsistence poaching remains a significant conservation challenge in the 21st century.
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- Title
- Advances in oscillometric blood pressure measurement
- Creator
- Chandrasekhar, Anand
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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High blood pressure (BP) is a major cardiovascular risk factor that is treatable, yet hypertensionawareness and control rates are low. Ubiquitous BP monitoring technology could improve hypertensionmanagement, but existing devices require an inflatable cuff and are not compatible withsuch anytime, anywhere measurement of BP. Oscillometry is the blood pressure (BP) measurementprinciple of most automatic cuff devices. We extended the oscillometric principle, which is usedby most automatic cuff...
Show moreHigh blood pressure (BP) is a major cardiovascular risk factor that is treatable, yet hypertensionawareness and control rates are low. Ubiquitous BP monitoring technology could improve hypertensionmanagement, but existing devices require an inflatable cuff and are not compatible withsuch anytime, anywhere measurement of BP. Oscillometry is the blood pressure (BP) measurementprinciple of most automatic cuff devices. We extended the oscillometric principle, which is usedby most automatic cuff devices, to develop a couple of instruments to measure cuff-less BP usinga smartphone-based device and standalone iPhone application. As the user presses her/his fingeragainst the smartphone, the external pressure of the underlying artery is steadily increased while thephone measures the applied pressure and resulting variable amplitude blood volume oscillations.A smartphone application provides visual feedback to guide the amount of pressure applied overtime via the finger pressing and computes systolic and diastolic BP from the measurements.We prospectively tested the smartphone-based device for real-time BP monitoring in humansubjects to evaluate usability (n = 30) and accuracy against a standard automatic cuff-based device(n = 32). We likewise tested a finger cuff device, which uses the volume-clamp method of BPdetection. About 90% of the users learned the finger actuation required by the smartphone-baseddevice after one or two practice trials. The device yielded bias and precision errors of 3.3 and 8.8mmHg for systolic BP and [Special character(s) omitted]5:6 and 7:7 mmHg for diastolic BP over a 40 to 50 mmHg range of BP.These errors were comparable to the finger cuff device. Cuff-less and calibration-free monitoringof systolic and diastolic BP may be feasible via a smartphone. In addition, we tested the iPhoneapplication. The application yielded bias and precision errors of -4.0 and 11.4 mmHg for systolicBP and -9.4 and 9.7 mmHg for diastolic BP (n = 18). These errors were near the finger cuff deviceerrors. This proof-of-concept study surprisingly indicates that cuff-less and calibration-free BPmonitoring may be feasible with many existing and forthcoming smartphones.These devices use empirical algorithms, already descried in the literature, to estimate bloodpressure. Hence, the next objective was to establish formulas to explain three popular empiricalalgorithms- the maximum amplitude, derivative, and fixed ratio algorithms. A mathematicalmodel of the oscillogram was developed and analyzed to derive parametric formulas for explainingeach algorithm. Exemplary parameter values were obtained by fitting the model to measuredoscillograms. The model and formulas were validated by showing that their predictions correspondto measurements. The formula for the maximum amplitude algorithm indicates that it yields aweighted average of systolic and diastolic BP (0.45 and 0.55 weighting) instead of commonlyassumed mean BP. The formulas for the derivative algorithm indicate that it can accurately estimatesystolic and diastolic BP (<1.5 mmHg error), if oscillogram measurement noise can be obviated.The formulas for the fixed ratio algorithm indicate that it can yield inaccurate BP estimates, becausethe ratios change substantially (over a 0.5-0.6 range) with arterial compliance and pulse pressureand error in the assumed ratio translates to BP error via large amplification (>40). The establishedformulas allow for easy and complete interpretation of perhaps the three most popular oscillometricBP estimation algorithms in the literature while providing new insights. The model and formulasmay also be of some value towards improving the accuracy of automatic cuff BP measurementdevices.
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- Title
- "Exile is hell" : Black internationalism and Robert F. Williams's activist network in the Cold War, 1950-1969
- Creator
- Mares, Richard M.
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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The precarious positions of African American political exiles provide an instructive window into the fluctuations of international support for the black freedom struggle. Exile Is Hell examines the strategies used by Robert F. Williams's activist network to survive and maintain their involvement in the Civil Rights-Black Power Movement from outside the United States. Expatriates such as Williams, Richard Gibson, Julian Mayfield, and others most plainly bore the vicissitudes of political...
Show moreThe precarious positions of African American political exiles provide an instructive window into the fluctuations of international support for the black freedom struggle. Exile Is Hell examines the strategies used by Robert F. Williams's activist network to survive and maintain their involvement in the Civil Rights-Black Power Movement from outside the United States. Expatriates such as Williams, Richard Gibson, Julian Mayfield, and others most plainly bore the vicissitudes of political shifts occurring in the 1960s against the backdrop of the Cold War. Exile Is Hell tracks this ebb and flow by foregrounding the day-to-day experiences of Williams, Gibson, Mayfield, and others to reveal their methods of navigating an erratic political climate and capricious activist community. International rhetoric formed an integral component of the Black Power era, yet many activists struggled to forge lasting, transnational coalitions due to the variable politics of the Cold War. Using Williams as the central hub of this activist network, this project contributes a detailed narrative of exile through a collective biography that explores the daily work of expanding the Civil Rights-Black Power Movement to incorporate global ambitions. This research further establishes the impact of changes in international support upon an activist network in order to extrapolate the effects on the African American freedom struggle.
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- Title
- Terminal stage of a dying rift
- Creator
- LaVigne, Andrew
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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While most continental rifts progress toward rupture and eventual oceanic spreading, in certain circumstances, the rift may fail. Failed rifts provide a window into the transition from continental rifting to the formation of a passive margin, which in successful rifts is occluded by thick post rift sedimentary packages. Among the best-preserved failed rifts is the 1.1 Ga Midcontinent Rift (MCR) in North America. Within the MCR, the final stage of magmatism is preserved on Michipicoten Island....
Show moreWhile most continental rifts progress toward rupture and eventual oceanic spreading, in certain circumstances, the rift may fail. Failed rifts provide a window into the transition from continental rifting to the formation of a passive margin, which in successful rifts is occluded by thick post rift sedimentary packages. Among the best-preserved failed rifts is the 1.1 Ga Midcontinent Rift (MCR) in North America. Within the MCR, the final stage of magmatism is preserved on Michipicoten Island. Here I present a geochemical and isotopic study of the Michipicoten Island Formation to probe conditions in the crust and mantle during the final stage. My results show that the volcanic units on Michipicoten Island have undergone magma mixing between rhyolitic and basaltic magma, dominating magmatic processes within the crust. During previous eruptive periods in the MCR, during which this observation has been made, the rhyolitic endmember has been interpreted to have experienced significant contribution from the Achaean crust based on profoundly unradiogenic Nd values. In contrast, the Michipicoten Island Formation exhibits some of the most radiogenic Ndi values in the MCR, indicating that the source of evolved melts in the MCR changes from melting of existing Archean crust to juvenile material. The isotopic data from Michipicoten Island also shows that the depleted mantle is the single largest contributor of any geochemical reservoir. In the absence of a strong thermal plume component, melting of the depleted mantle requires decompression. The Michipicoten Island Formation was erupted during the geophysically-defined post-rift phase. My results require plate thinning to have continued during this late stage, with the implication that plate deformation persisted even though the crustal structure may not have recorded this deformation.
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- Title
- Repatriation tax costs and foreign investment decisions of U.S. multinationals : evidence from the anticipation of the 2017 U.S. tax reform
- Creator
- Vuong, Anh Nguyet
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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"In this study, I investigate whether the expectation of a future reduction in repatriation tax costs affects the foreign investment decisions of U.S. multinational corporations (U.S. MNCs). I find that, during the period in which members of Congress proposed legislation for a switch to a territorial tax system, foreign subsidiaries of U.S. MNCs significantly increased capital investment activities, compared to the subsidiaries of non-U.S. MNCs in the same country. The increase in capital...
Show more"In this study, I investigate whether the expectation of a future reduction in repatriation tax costs affects the foreign investment decisions of U.S. multinational corporations (U.S. MNCs). I find that, during the period in which members of Congress proposed legislation for a switch to a territorial tax system, foreign subsidiaries of U.S. MNCs significantly increased capital investment activities, compared to the subsidiaries of non-U.S. MNCs in the same country. The increase in capital investment is concentrated among subsidiaries of U.S. MNCs that are subject to higher potential repatriation tax costs, and hence would benefit more from a potential reform. Furthermore, I do not find any evidence consistent with the alternative explanation that agency costs of excess cash holdings drive the increases in investment during this period. On the contrary, the increases in foreign investment activities are marginally greater among subsidiaries that are subject to lower agency costs. Together, these results suggest that the expectation of lower future repatriation tax costs has inadvertently incentivized U.S. MNCs to invest more abroad. My study contributes to the literature that examines firms' real investment responses to anticipated tax incentives and our understanding of the consequences of the recent U.S. tax reform."--Page ii.
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- Title
- Quantitative investigation of the membrane protein degradation mechanism by membrane-integrated AAA protease FtsH under native environments
- Creator
- Yang, Yiqing (Graduate of Michigan State University)
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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"Controlled degradation of misassembled and dispensable proteins is a crucial cellular process for maintaining the quality control of proteomes. In cells, one of the important carriers of this process is AAA+ (ATPases Associated with diverse cellular Activities) proteases, which mediate ATP-dependent proteolysis. The FtsH family proteins are the only membrane integrated AAA+ proteases, which critically contribute to membrane protein degradation. To investigate the mechanisms of membrane...
Show more"Controlled degradation of misassembled and dispensable proteins is a crucial cellular process for maintaining the quality control of proteomes. In cells, one of the important carriers of this process is AAA+ (ATPases Associated with diverse cellular Activities) proteases, which mediate ATP-dependent proteolysis. The FtsH family proteins are the only membrane integrated AAA+ proteases, which critically contribute to membrane protein degradation. To investigate the mechanisms of membrane protein degradation mediated by FtsH, I successfully reconstituted the degradation process using FtsH of E. coli in a lipid bilayer environment (Chapter 2). I also developed a six-helical bundle intramembrane protease GlpG of E. coli into a model membrane substrate to study the quantitative relationship between folding and degradation (Chapter 2). I found that FtsH has a substantial ability to accelerate unfolding of membrane substrates up to 800 fold using ATP hydrolysis, and the intrinsic folding properties of the substrates such as local stability, spontaneous unfolding rates, and hydrophobicity also impact degradation rates. Finally, I quantified the total ATP cost that FtsH consumes to degrade membrane proteins (Chapters 3 and 4). To degrade membrane proteins, FtsH needs to overcome large energetic costs for unfolding substrates in the membranes and extracting them towards its protease domain located outside the membrane. I found that FtsH utilizes ATP hydrolysis in degrading membrane proteins with similar efficiency to other AAA+ proteases in degrading water-soluble substrates. This efficiency is achieved by coupling multiple ATP hydrolysis events to degradation in a highly cooperative manner. These findings provide new insights into the physical principles of ATP-dependent degradation of membrane proteins, and the in vitro system developed will serve as a model for further refining the mechanisms of membrane protein degradation."--Pages ii-iii.
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- Title
- Testing phonological representations through behavioral and electrophysiological methods
- Creator
- Trotter, Andrew (Graduate of Michigan State University)
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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Languages differ in the sounds that make up their phonemic inventories. These sounds, or phonemes, are represented abstractly in the mind of a speaker, making up the underlying representations of lexical items. Additional sounds may exist in a given language, surfacing via a derivative process of phonological rule application, where they are called allophones. There are also many speech sounds that are unrepresented entirely, as separate categories, within a particular language. In either...
Show moreLanguages differ in the sounds that make up their phonemic inventories. These sounds, or phonemes, are represented abstractly in the mind of a speaker, making up the underlying representations of lexical items. Additional sounds may exist in a given language, surfacing via a derivative process of phonological rule application, where they are called allophones. There are also many speech sounds that are unrepresented entirely, as separate categories, within a particular language. In either case, learners of a second language have difficulty perceiving and producing the sounds that do not exist or have differing phonological status in their native language. English and Spanish present us with an ideal case study of these differences. Both languages contain the [d], [ð], and [027E] sounds, but they differ in how they organize them. While /d/ is a phoneme in both languages, in Spanish [ð] is an allophone of /d/, while /027E/ is a separate phoneme. Conversely, [027E] is an allophone of /d/ in English while /ð/ is a separate phoneme. There is a large amount of literature showing that sounds that contrast in one's language are more perceptible than those that do not. Boomershine et al., (2008) showed this to be true of the [d], [ð], and [027E] sounds in native Spanish and English speakers, where Spanish speakers more easily perceived the differences between [d]/[027E] than [d]/[ð]. English speakers, on the other hand, had difficulty distinguishing [d] from [027E], but no issue with [d] and [ð]. The studies in this dissertation extend this work by first replicating the results of Boomershine et al., (2008) with a group of monolingual English speakers as well as a group of native Spanish speakers on a forced choice perception task. Additionally, I add a group of native English-speaking advanced learners of Spanish and show that their perception of the relevant sounds is more like that of the native Spanish speakers on a number of behavioral metrics. In a second study, I test the same three speaker groups in an Electroencephalography study (EEG) using the mismatch negativity protocol (MMN) which has been previously shown to probe auditory categorical perception (Naatanen et al., 1978). If the MMN is sensitive to phonemic contrasts, as has been claimed, the expectation is that, similarly to the behavioral perception results, speakers should show larger mismatch responses to phonemic contrasts than to allophonic contrasts. I also explore the possibility of using the MMN to probe category formation in the learner group. However, while there are subtle differences in the EEG data for each speaker group, the results are contra predictions. Instead, all three language groups pattern similarly on each sound in the EEG study, with larger MMNs being elicited by the [027E]/[d] comparison than the [ð]/[d] comparison. This mismatch response suggests that the MMN is not probing phonological status but is sensitive to phonetic category. A discussion of methodology and the validity of using the MMN in phonology research is included.
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- Title
- Antimicrobial and biodegradable food packaging films with chitosan-based N-halamine structures to prevent contamination by drug susceptible and resistant strains of Salmonella typhimurium
- Creator
- Thekkudan Novi, Vinni
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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Contamination of food samples with antibiotic resistant Salmonella Typhimurium has become a cause for concern due to difficulty in treating infections caused by this pathogen. In one approach, chitosan/PVA-based N-halamine (CPN) film was developed and tested for its efficacy in inactivating drug susceptible and ampicillin resistant Salmonella Typhimurium strains. The CPN film significantly (100%) inactivated the growth of both strains during the antimicrobial sandwich assay when tested for...
Show moreContamination of food samples with antibiotic resistant Salmonella Typhimurium has become a cause for concern due to difficulty in treating infections caused by this pathogen. In one approach, chitosan/PVA-based N-halamine (CPN) film was developed and tested for its efficacy in inactivating drug susceptible and ampicillin resistant Salmonella Typhimurium strains. The CPN film significantly (100%) inactivated the growth of both strains during the antimicrobial sandwich assay when tested for five days since film preparation, while the CH/PVA films showed around one log reduction (p<0.05). CPN films reduced the drug resistant strain's growth on cheddar cheese slices by 5-6 logs at 25°C and 3-4 logs at 4°C when packaged and stored over a period of five days unlike CH/PVA films that did not show significant reduction. The second approach involves the synthesis of a stronger chitosan N-halamine-based coating on plasma treated polycaprolactone film (CH-NX/PCL film). The FTIR peaks obtained for chitosan coated PCL film (CH/PCL) showed characteristic peaks of both PCL and chitosan, specifically at 1720 cm-1 and 3354 cm-1, respectively. The tensile strength of the PCL was higher, while the Young's modulus value was higher for CH/PCL. CH/PCL film showed better barrier against water and oxygen compared to PCL. The antimicrobial efficacy of the CH-NX/PCL film was 100% against both strains of Salmonella Typhimurium when compared to PCL and CH/PCL, indicating that this fabricated film has promising applications in food safety.
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