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Title: Lost or found : experiences of first-year Chinese international students who are on academic probation after their first semester
Creator: Mei, Jianyang
Date: 2019
Collection: Electronic Theses & Dissertations
Description: In recent years, the number of Chinese international undergraduate students sharply increased in higher education institutions in the U.S. Meanwhile, this student population experiences challenges in their transition in U.S. colleges, and academic probation is one challenge that Chinese international undergraduate students have. Being on academic probation has negative impacts on students' persistence and retention rates and 4,5,6-year graduation rates, and the increasing number and...
Show moreIn recent years, the number of Chinese international undergraduate students sharply increased in higher education institutions in the U.S. Meanwhile, this student population experiences challenges in their transition in U.S. colleges, and academic probation is one challenge that Chinese international undergraduate students have. Being on academic probation has negative impacts on students' persistence and retention rates and 4,5,6-year graduation rates, and the increasing number and percentage of Chinese international students also bring challenges to U.S. higher education institutions. To explore the reasons for being on academic probation of Chinese international undergraduate students, this research studied the experiences of the first-year Chinese international undergraduate students who are on academic probation after their first semester in a Research I public university. This mix-method study collected data of students' educational records, survey, and interview, in order to explore the trends among first-year Chinese international undergraduate students who are on academic probation after their first semester, the correlations between their TOEFL, SAT, ACT scores and first semester GPAs, their academic performance in each course they enrolled in their first semester, and how those students perceived and made sense of being on academic probation. The data analysis demonstrated that the most reasons for being on academic probation after their first semester are in socio-emotional engagement, not in academic proficiency. The top 2 main reasons for being on academic probation identified by interviewees are not taking their study seriously and not studying (hard). Different from many studies about (Chinese) international students, the language barrier was not identified as one top reason for being on academic probation by survey respondents and interviewees. The main finding of this study is the goal of participants was to get an admission letter from a U.S. college. Participants actually only prepared for the study abroad tests, such as TOEFL, SAT, and ACT, and did not prepare for knowledge, skills, and abilities that are essential to survive and thrive in the academic learning at U.S. colleges. This study also found being on academic probation is actually an issue caused by the study abroad craze that driven by policy and capital, and it needs the effort and input from Chinese international students, Chinese parents, and U.S. higher education institutions in order to solve this problem. Therefore, this study provided recommendations to Chinese international students and Chinese parents, as well as faculty, staff, and administrators in U.S. colleges at the individual level, institutional level, and policy level, in order to support the academic learning and transition of Chinese international undergraduate students.
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Title: Barcoding, metabarcoding, and experimental analyses of community dynamics and environmental conditions affecting predation of larval lake sturgeon in the Black River, Michigan
Creator: Waraniak, Justin
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The larval stage of most fishes is characterized by high levels of mortality and is likely a bottleneck to recruitment for many populations. Predation is an important source of mortality for the larval stage of many fish species, and is a possible factor driving high mortality in some populations. Lake sturgeon are a species of conservation concern in the Great Lakes region, with many populations experiencing little to no natural recruitment and high mortality rates during the vulnerable egg...
Show moreThe larval stage of most fishes is characterized by high levels of mortality and is likely a bottleneck to recruitment for many populations. Predation is an important source of mortality for the larval stage of many fish species, and is a possible factor driving high mortality in some populations. Lake sturgeon are a species of conservation concern in the Great Lakes region, with many populations experiencing little to no natural recruitment and high mortality rates during the vulnerable egg and larval early life stages. Predation of larval lake sturgeon, and larval fishes generally, has been difficult to quantify with morphological diet analyses due to rapid digestion times in the gastrointestinal (GI) tracts of predators. This study developed and utilized alternative molecular genetic methods to detect larval lake sturgeon in the diets of predator fishes, as well as conducting an experiment to further examine findings of the molecular diet analysis. Sturgeon-specific barcoding analysis of the COI mtDNA region quantified the predation frequency predation of larval lake sturgeon and revealed increased abundance of alternative prey and abiotic factors that lowered visibility could reduce predation of larval lake sturgeon. Metabarcoding analysis of predator diets using universal 18S rRNA primers revealed seasonal dietary shifts of predators when larval lake sturgeon were present in the prey community compared to after lake sturgeon larvae were no longer available, but that lake sturgeon larvae made up a small portion of the overall diets of predator fishes. Experimental manipulations of relative prey abundance quantified how the prey community could affect predator preferences. This study exemplifies the utility and improved accuracy of molecular tools in detecting predation of larval fish and other soft-bodied prey compared to morphological analyses, as well as the importance of the biotic community and environmental factors influencing predation mortality in larval fishes.
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Title: Socio-economic context for participatory forest landscape restoration monitoring in Malawi
Creator: Tumeo, Tangu Isabel
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Malawi aims to achieve 4.5 million hectares of restored landscapes by 2030. Using comprehensive approaches like Forest Landscape Restoration (FLR). Monitoring the progress of FLR is crucial for effective and efficient implementation with relevant information and feedback. Nonetheless, systems that encourage local participation in monitoring of FLR interventions are lacking. The study assesses the socio-economic context for sustainable and successful forest landscape restoration participatory...
Show moreMalawi aims to achieve 4.5 million hectares of restored landscapes by 2030. Using comprehensive approaches like Forest Landscape Restoration (FLR). Monitoring the progress of FLR is crucial for effective and efficient implementation with relevant information and feedback. Nonetheless, systems that encourage local participation in monitoring of FLR interventions are lacking. The study assesses the socio-economic context for sustainable and successful forest landscape restoration participatory monitoring. An understanding of this is part of creating an enabling environment for participatory monitoring in tracking the progress of the national forest landscape restoration strategy. Using Machinga district as a study site, evidence has been established for the consideration of socio-economic factors to encourage local participation in FLR monitoring. Participatory monitoring of FLR when designed to include local communities and adapted to diverse needs, opinions and conditions have the potential to complement highly technical monitoring of the National Forest Landscape Restoration Strategy. Therefore, to motivate local communities to participate in FLR monitoring, implementers will have to consider satisfying economic and welfare basic needs consistent with the physical, socio-economic environment. Otherwise, these needs left unaddressed may threaten the sustainability of forest and land restoration monitoring and implementation.
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Title: Social relationships and progression of frailty : exploring the reciprocal association of social ties and physical vulnerability in later life
Creator: Lee, Ji Hyun (Graduate of Michigan State University)
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Frailty is described as a state of heightened vulnerability and functional impairment due to the cumulative declines across multiple physiological systems. When faced with stressor events, older adults with frailty are in higher risk of adverse health outcomes. While the prevalence of frailty generally increases with age, there are considerable heterogeneity in onset and progression of frailty among older population. Growing attention is given to identifying the psychosocial factors related...
Show moreFrailty is described as a state of heightened vulnerability and functional impairment due to the cumulative declines across multiple physiological systems. When faced with stressor events, older adults with frailty are in higher risk of adverse health outcomes. While the prevalence of frailty generally increases with age, there are considerable heterogeneity in onset and progression of frailty among older population. Growing attention is given to identifying the psychosocial factors related to the development of frailty. Social relationships often serve as a vital context of health, where older adults experience multidimensional and dynamic exchange with close others as they age. In this dissertation, two studies are conducted to investigate complex and reciprocal nature of social relationships and frailty progression in older adulthood. The data are from the six waves (2006-2016) of the Health and Retirement Study (HRS), a nationally representative study of older adults in U.S. aged 50 and older. The first study utilized the convoy model of social relations to provide comprehensive investigation of how different aspects of social relations are associated with frailty progression over a decade. There were three distinctive subpopulations following a different frailty progression trajectory. When social network and relational quality with spouse, children, family, and friends were examined, higher frequency of contact with friends were associated with lesser frailty. Negative relationship quality with social ties were detrimental to frailty progression, such that strain with spouse and kin (children and extended family) had an additive effect on belonging to high frailty or steep increase frailty trajectory groups. The perceived loneliness partially explained the negative effect of spousal strain, but the negative effect of large family size and strain with kin were independent from loneliness. The second study explored the health contexts of older couple's marital quality, specifically focusing on the presence of frailty and depression within- and across-person in the marital relationship. Using three waves of dyadic data from HRS, I found that one's own and partner's higher frailty and higher depression all had independent associations with one's higher marital strain. For one's marital support, one's own higher frailty, higher depression, and partner's higher depression had negative effects. There was an across-person interaction effect of frailty, such that one's marital quality was affected by their partner's higher level of frailty only when their own health was good. Having a husband with higher frailty was associated with higher marital strain for wives. Most effects were stable over time. Overall, the findings illustrate the significance of social relationship context as a predictor for different trajectory of frailty progression. The size, frequency of contact, positive, and negative quality were linked to frailty differentially by relationship type, underscoring the benefits of comprehensive examination of social experiences. Further, the level of frailty and depression were linked to perceived marital quality of both members of the couple, especially in damaging manner when healthier spouse is faced with partner's health problems. Taken together, my dissertation demonstrated the importance of studying linked lives in context of health conditions prevalent in older adulthood. The findings can be useful to practitioners and policy makers in understanding the intricate link between social relations and frailty as well as in identifying modifiable factors for frailty prevention.
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Title: Structural and functional remodeling of neuronal circuitry surrounding implanted electrodes
Creator: Salatino, Joseph William
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Microelectrode arrays designed to map and modulate neuronal circuitry have enabled greater understanding and treatment of neurological injury and disease. However, poor biological integration remains a significant barrier to the longevity and stability of electrodes implanted in the brain, where gliosis and neuronal loss are commonly attributed to instability and loss of signal over time. However, these metrics do not reliably predict signal loss, and device failure modes remain elusive. Here...
Show moreMicroelectrode arrays designed to map and modulate neuronal circuitry have enabled greater understanding and treatment of neurological injury and disease. However, poor biological integration remains a significant barrier to the longevity and stability of electrodes implanted in the brain, where gliosis and neuronal loss are commonly attributed to instability and loss of signal over time. However, these metrics do not reliably predict signal loss, and device failure modes remain elusive. Here, this work provides fundamental insight into biological mechanisms that contribute to these failure modes, as well as develops genetic engineering strategies to improve the biointegration of brain implants.While signal-generating neurons have traditionally been considered the important target cells for implanted electrodes, it has become increasingly appreciated that glia remodel the structure and function of neuronal networks following injury, where recent work has uncovered mechanisms relevant to the injuries and ensuing gliosis caused by the implantation of chronic devices. Chapter 2 disseminates important considerations for glial reactivity on device performance and provides a framework for topics explored in subsequent Chapters. Although decades of work has demonstrated that cortical injury generates long-term remodeling of excitatory/inhibitory synapses (the connections which facilitate the propagation of information between neurons) and ion channels (the transmembrane proteins responsible for generating neuronal signals), these mechanisms have not been investigated around implanted arrays; however, the consequences of these events hold significant implications for the long-term recording stability of implanted devices. Chapter 3 reveals novel changes in both excitatory and inhibitory synaptic circuitry surrounding implanted microelectrodes, where early elevations in excitatory synapses are followed by a shift to inhibitory tone in the chronic setting. A novel subtype of glia is also identified local to the device interface. Chapter 4 reveals a novel relationship between electrophysiological recordings and ion channel expression surrounding implanted arrays over time, where a loss of sodium channel expression and gain in potassium channel expression corresponds with a loss of recorded signals over time. Together, this work supports a trend from hyper- to hypo-excitability, which temporally coincides with signal variability and loss observed with chronic devices.The previous chapters provide fundamental insight into major circuit changes at the interface that inform both basic-science knowledge and new strategies for improving the biointegration of brain implants. We are developing new approaches to reveal the mechanistic role of these factors in affecting recorded signals over time. Chapter 5 covers ongoing work that includes the development and validation of innovative strategies to deliver genetic material at the interface in vivo to yield entirely new avenues of research with opportunities to regulate gene expression and/or introduce new genetic material to rewire the interfacial network. Future directions are discussed with opportunities to unmask key circuit-remodeling effects that impair device performance as well as inform the seamless integration of brain implants.
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Title: Production potential of chitosan as a value added coproduct for sugar beet processing facilities
Creator: Sheridan, Patrick M. (Patrick Micheal)
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "Sugar beet pulp residues (SBP) were used as a feedstock for Rhizopus oryzae fermentation to produce a value added product -- chitosan. Enzymatic conditions for effective liberation of fermentable sugars from SBP were identified. Nitrogen sources, nutritional salts, and plant hormones were investigated as a means to improve the chitosan yield. Optimum conditions identified were applied to a large-scale flask culture. Fungal glucosamine yields reached 3.6% (per gram of SBP input, glucosamine...
Show more"Sugar beet pulp residues (SBP) were used as a feedstock for Rhizopus oryzae fermentation to produce a value added product -- chitosan. Enzymatic conditions for effective liberation of fermentable sugars from SBP were identified. Nitrogen sources, nutritional salts, and plant hormones were investigated as a means to improve the chitosan yield. Optimum conditions identified were applied to a large-scale flask culture. Fungal glucosamine yields reached 3.6% (per gram of SBP input, glucosamine is the monomer unit of chitosan). The economics of a fungal fermentation system for a SBP production of 2,000 metric tons per year was analyzed based on the results achieved in 2L flask culture. Compared to the current application of SBP as animal feed, the high value of the chitosan significantly enhanced the economic performance. A payback period of slightly over 7 months was correspondingly achieved for the studied fungal chitosan production."--Page ii.
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Title: Optical transmission scanning and hybrid acousto-optical techniques for NDE and SHM of structural composites
Creator: Karpenko, Oleksii
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Fiber reinforced polymer (FRP) composites have been extensively used in aerospace, marine and defense industries due to the many advantages they offer including light-weight, corrosion resistance and excellent thermo-mechanical properties. Increasing fuel-efficiency demands and reducing green-house emissions has also propelled the use of FRP composites in the automotive industry. However, despite excellent mechanical properties of FRPs, their anisotropy, brittle nature and the vulnerability...
Show moreFiber reinforced polymer (FRP) composites have been extensively used in aerospace, marine and defense industries due to the many advantages they offer including light-weight, corrosion resistance and excellent thermo-mechanical properties. Increasing fuel-efficiency demands and reducing green-house emissions has also propelled the use of FRP composites in the automotive industry. However, despite excellent mechanical properties of FRPs, their anisotropy, brittle nature and the vulnerability to flaws during fabrication and service has propelled the need of nondestructive evaluation (NDE) and structural health monitoring (SHM) techniques. This dissertationpresents three major contributions to the fields of NDE and SHM of structural composites:• optical transmission scanning (OTS) for rapid, non-contact and quantitative NDE of glass and aramid FRPs;• optical frequency-domain reflectometry (OFDR) for distributed monitoring of strains in FRPs using single-mode (SM) optical fibers and Rayleigh back-scattering;• hybrid acousto-optic health monitoring of FRPs using guided waves (GW) and Fabry-Perot interferometric sensors based on chirped fiber Bragg-gratings (CFBG-FPI).Chapter I presents an OTS system for quantitative NDE of GFRP samples. The technique provides high-resolution, rapid, and non-contact optical transmittance scans. Experimental implementation of the technique and advanced data analysis protocol developed for impact damage evaluation are presented. Obtained experimental results show that other defects and certain microstructural variations in GFRP composites can be easily identified by OTS, because the technique is sensitive to localized changes of optical properties such as radiation absorption and scattering. The applications of OTS are extended to GFRP plates with improperly mixed resin, inclusions, and delaminations. Finally, the capabilities of the technique to evaluate the distribution of adhesive and detect fatigue damage in adhesively bonded GFRP joints are demonstrated.Chapter II describes the development of advanced signal processing algorithms for strain sensing in optical fibers using Rayleigh back-scattering and the OFDR technique. Distributed displacement and strain sensing along the fiber length is implemented using the OFDR-1000 system from General Photonics Corporation (Chino, CA). Performance of the system is validated by measuring strains introduced in the optical fiber by the piezoelectric fiber stretcher. Chapter III lays out the approach for diagnostic imaging of plate-like structures using hybrid acousto-optic technique. Guided waves are excited with surface-bonded piezoelectric wafers and are sensed with pairs of chirped fiber Bragg-gratings that form Fabry-Perot interferometers inside the surface-bonded optical fiber. Initial experimental results obtained on aluminum plates demonstrate that CFBG-FPIs are sensitive to both symmetric and antisymmetric fundamental GW modes. Structural damage is successfully located using Delay-and-Sum (DAS) imaging.
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Title: The life and death of bone : a regional approach to the interpretation of fragmented and culturally modified Oneota human remains
Creator: Geske, Nicole Lynne
Date: 2018
Collection: Electronic Theses & Dissertations
Description: This dissertation utilizes previously collected archaeological, mortuary, and osteological data from multiple village and mortuary sites attributed to the Midwest archaeological culture known as Oneota (AD 900-1700). Isolated and fragmented human remains are commonly encountered in both mortuary and non-mortuary contexts, including burials, refuse and storage pits, and scattered throughout villages and middens. Many of these remains are also culturally modified through processes such as...
Show moreThis dissertation utilizes previously collected archaeological, mortuary, and osteological data from multiple village and mortuary sites attributed to the Midwest archaeological culture known as Oneota (AD 900-1700). Isolated and fragmented human remains are commonly encountered in both mortuary and non-mortuary contexts, including burials, refuse and storage pits, and scattered throughout villages and middens. Many of these remains are also culturally modified through processes such as burning, incising, and polishing. Although research regarding these remains is limited, these deposits have been attributed to violence and/or trophies of war. Therefore, the primary objective of this research was to examine the presence of fragmented and culturally modified human remains at Oneota sites and to theorize their possible meaning(s). This also included an evaluation of previous conclusions of violence. A secondary objective of this dissertation was to assess if published and previously collected data could be used to answer new research questions. Using spatial and correspondence analyses, this dissertation demonstrates patterning in the presence and location of culturally modified human remains. A contextual approach, as well as a theoretical framework that views the body as dividual and partible, were also used to demonstrate how human remains can become fragmented and isolated. Finally, ethnographies of the Winnebago (Ho-Chunk) and Ioway were used to find historical links between past and historic practices. This dissertation demonstrates a preference for cranial and long bone elements for fragmentation, as well as cultural modification. The choice of cranial elements is tied to the concept of the location of the soul, while the act of cultural modification is a transformation to either enhance or erase previously identities. Due to the degree of fragmentation, it cannot be precisely determined who specifically was used for this treatment. It is argued that these remains represent an aspect of the Oneota mortuary program that has not regularly been included in previous analyses.Multiple difficulties in data collection and analysis were encountered, primarily for data regarding fragmented and isolated human remains. Several varying treatments for isolated human remains were noted, leading to difficulty in their analysis and interpretation. Due to this difficulty, suggestions for future data collection for isolated human remains are provided.
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Title: The effect of artific[i]al drying of field corn in different stages of maturity on the vitality of the seed
Creator: Marston, Arthur R.
Date: 1926
Collection: Electronic Theses & Dissertations

Title: Topical outline of highway traffic control
Creator: Ireland, Mark L.
Date: 1924
Collection: Electronic Theses & Dissertations

Title: CONSUMER RESPONSES TO INTENSE NEGATIVE EMOTION IN ELECTRONIC WORD-OF-MOUTH : THE ROLE OF TIE-STRENGTH AND DIAGNOSTIC CUES
Creator: Kim, Wonkyung
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Social media have become widely used platforms for dissatisfied customers to express disappointment with failed goods and services. Referred to as an online “firestorm,” negative eWOM spreads instantly and exponentially through people’s social networks (Pfeffer, Zorbach, & Carley, 2014). Marketers may worry that strong emotional expression of a complaint would lead to negative brand consequences, but that is an empirical question. Guided by Attribution theory and Accessibility-Diagnosticity...
Show moreSocial media have become widely used platforms for dissatisfied customers to express disappointment with failed goods and services. Referred to as an online “firestorm,” negative eWOM spreads instantly and exponentially through people’s social networks (Pfeffer, Zorbach, & Carley, 2014). Marketers may worry that strong emotional expression of a complaint would lead to negative brand consequences, but that is an empirical question. Guided by Attribution theory and Accessibility-Diagnosticity model, this study examined how tie-strength and diagnostic information influence consumers’ inference-making of intense negative eWOM sender motives which in turn leads to credibility perceptions. An online experiment manipulated tie strength and the behavioral patterns of diagnostic cues to address the as yet unstudied effects of negative eWOM on credibility perception, attitude toward the brand, and sharing intention.This study used a 3 (Tie-strength: strong vs. weak vs. none) x 4 (Cues Present [high consistency/ medium consistency/ low consistency], Not Present) between-subjects, posttest only random assignment factorial experimental design. The results showed that the consistency of behavioral pattern manifested in previous posts of the eWOM sender influences attribution of sender’s motives. That is, when the original negative eWOM and the previous posts show consistently high consistency (i.e., negative valence posts), receivers made more dispositional attributions compared to when the previous posts showed low consistency (i.e., positive valence posts). Such impact of the previous posts was moderated by the tie-strength between the sender and the receiver. When the source is a close friend, receivers did not consider the cues of past behavioral pattern, unlike receivers who viewed a post from an acquaintance or a stranger as a sender of intense negative eWOM. Furthermore, indirect effects suggest that attribution of sender motives further influences persuasive outcomes such as brand attitude and sharing intention. The results give some implications for brand managers and eWOM platform developers. First, those who manage social media consumer complaints should consider the network of eWOM senders. Second, eWOM platforms should consider ways to highlight diagnostic cues such as previous posts. Previous posts can be emphasized by showing the previous rating history of the reviewer. In this way, receivers would not necessarily visit the eWOM sender’s profile page to gather more information on previous eWOM behaviors.
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Title: The impact of the government concealing information on the practice of journalism : a study of Anglophone Cameroonian journalists
Creator: Ngwe Ali, Pechulano
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "This study seeks to understand how a press freedom-related issue such governmental controls of governmental? information affects journalism practice. The study used a survey of 172 practicing Anglophone Cameroonian journalists from private and state media, and in-depth interviews. Interviewees were heads of journalism unions/associations, a media regulatory agency (the National Communication Council), and media owners, publishers, and editors. Results show that the government uses a...
Show more"This study seeks to understand how a press freedom-related issue such governmental controls of governmental? information affects journalism practice. The study used a survey of 172 practicing Anglophone Cameroonian journalists from private and state media, and in-depth interviews. Interviewees were heads of journalism unions/associations, a media regulatory agency (the National Communication Council), and media owners, publishers, and editors. Results show that the government uses a combination of legislative and administrative practices - - mostly through sanctions from the media regulatory body and police harassment--to effectively enforce and monitor control of information. Barriers to accessing government information were found to be: long wait times during appointments with officials, unending referrals to bosses/superiors, delaying press conferences until state media are present, and delaying replies to requests for information, among others. This study argues that coupled with legislative and administrative practices, these barriers lead to imbalanced reporting and ethical compromise. While governmental control of information was sometimes explained by lack of training and unprofessionalism, the practices stifle the development of responsible journalism, shrinking audiences and creating widespread cynicism about local journalistic ethics. The cynicism can also be explained by the fact that some reporters have been known to accept bribes from government officials and agencies, and rich business owners in exchange for not running scandal stories. This practice has been named 'gombo journalism' in Cameroon."--Page ii.
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Title: Learning algorithms for detecting disinformation on social media
Creator: VanDam, Courtland
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Social media has become a widely accessible medium for users to share their opinions and details of their personal lives, including first hand accounts of emerging/disaster events, to a wide audience. However malicious entities may abuse users' trust to disseminate disinformation, i.e. false and misleading information. The disinformation disseminated on social media can have a significant impact offline. For example, fake news is suspected to have influenced the 2016 U.S. political election....
Show moreSocial media has become a widely accessible medium for users to share their opinions and details of their personal lives, including first hand accounts of emerging/disaster events, to a wide audience. However malicious entities may abuse users' trust to disseminate disinformation, i.e. false and misleading information. The disinformation disseminated on social media can have a significant impact offline. For example, fake news is suspected to have influenced the 2016 U.S. political election. Rumors on social media can mislead criminal investigations, e.g. the investigation of the 2013 Boston Bombing. To mitigate such impacts, automated detection of social media disinformation is thus an important research problem. This dissertation proposes algorithms to detect two approaches hackers use to disseminate disinformation-hashtag hijacking and compromising accounts. Hashtags are terms added to social media posts that are used to provide context to the posts, so those seeking to learn more about a given topic or event can search for posts containing related hashtags. However critics and attention-seeking trolls can mislead the public via hashtag hijacking. Hashtag hijacking occurs when one group of users takes control of a hashtag by using it in a different context than what was intended upon creation. Anyone can participate in hashtag hijacking, but to be successful, a coordinated effort among several accounts posting that hashtag is needed. This dissertation proposes HASHTECT, an unsupervised learning framework that uses a multi-modal nonnegative matrix factorization method for detecting hijacked hashtags. Experimental results on a large-scale Twitter data showed that HASHTECT is capable of detecting more hijacked hashtags than previously proposed algorithms. Another approach for disseminating disinformation is by compromising users' accounts. A social media account is compromised when it is accessed by a third party, i.e. hacker, without the genuine user's knowledge. Compromised accounts are damaging to the account holder as well as the accounts audience, e.g. followers. Hackers can damage the user's reputation, e.g. by posting hateful rhetoric. They also disseminate misleading information including rumors and malicious websites, e.g. phishing or malware. In this dissertation, I propose two compromised account detection algorithms, CADET and CAUTE. CADET is an unsupervised multi-view learning framework that employs nonlinear autoencoders to learn the feature embedding from multiple views. The rationale behind this approach is that an anomalous behavior observed in one view, e.g. abnormal time of day, may not indicate a compromised account. By aggregating the data from multiple views, CADET projects the features from all the views into a common lower-rank feature representation and detects compromised accounts in the shared subspace. On the other hand, CAUTE focuses on detecting compromised accounts early, by detecting the compromised posts. Given a user-post pair, CAUTE is a deep learning framework which simultaneously learns the encodings for the user as well as the post to detect whether the post was compromised, i.e. was written by a different user. By training a neural network on the residuals from the post and user encodings, CAUTE can classify whether a post is compromised with higher accuracy than several existing compromised account detection algorithms.
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Title: Investigating complexity in transcriptome expression, regulation, and evolution using mathematical modeling
Creator: Panchy, Nicholas Louis
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "To date, gene expression has been characterized in over one thousand species across more than a million experimental conditions. With this wealth of data, it is possible to investigate the role that differential expression has in key biological processes, such as development, stress response, and cell division. However, the complexity of the transcriptome makes the analysis of expression challenging, as a single genome can contain thousands of genes as well as millions of potential...
Show more"To date, gene expression has been characterized in over one thousand species across more than a million experimental conditions. With this wealth of data, it is possible to investigate the role that differential expression has in key biological processes, such as development, stress response, and cell division. However, the complexity of the transcriptome makes the analysis of expression challenging, as a single genome can contain thousands of genes as well as millions of potential regulatory interactions shaped by more than a billion years of evolution. To address this complexity, we can use the language of mathematics to create models of gene expression, regulation, and evolution that define the system in a testable format. In the following chapters, I will present research that applies mathematical modeling to the identification and regulation of cyclically expressed genes as well as the evolution of transcriptional regulators following whole genome duplication. Cyclically expressed genes were studied in two systems. First, I investigated day-night cycling or 'diel' genes in Chlamydomonas reinhardtii. Diel genes were identified de novo using two models of cyclic expression that jointly classified half of all genes in C. reinhardtii as diel expressed. To understand the regulation of diel expression, I clustered diel genes according their peak of expression, or 'phase', and searched for cis-regulatory elements enriched (CREs) in the promoters of each cluster. While I found putative CREs corresponding to each cluster, using these CREs to predict diel expression using machine learning performed poorly compared to previous models of expression regulation. Therefore, I changed systems to Saccharomyces cerevisiae and studied cyclic expression during the cell cycle. Here, I applied machine learning models to predict cell-cycle expression using regulatory interactions from four different data sets. These models out performed the previous model of cyclic expression when using regulatory interactions defined by chromatin-immunoprecipitation, transcription factor knockout experiments, and position weight matrices. Further gains in performance were obtained by combing interactions across data sets and using co-regulation by pairs of regulators involved in feed-forward loops. The most important interactions for predicting cell-cycle expression included not only known cell-cycle regulators but also two groups of transcription factors not previously identified as being involved in cell-cycle regulation. The evolution of transcriptional regulation was studied in Arabidopsis thaliana, which has undergone several rounds of whole genome duplication (WGD), after which transcriptions factors (TFs) are preferentially retained. Here, I applied maximum likelihood estimation to infer the most likely ancestral expression and regulatory state of pairs of duplicate TFs prior to WGD. Comparing this ancestral state to the existing TF duplicates, I found that one duplicate, the "ancestral' copy, tends to retain the majority of ancestral expression state and CREs, while the other 'non-ancestral' copy loses ancestral expression and CREs, but also gains novel CREs instead. Modeling the evolution of TFs pairs using as system of ordinary differential equations, I demonstrated that the partitioning of ancestral states amongst duplicates is not random, but occurs because the loss of ancestral expression occurs orders of magnitude faster in the first copy than in the second. This suggests that TFs duplicate pairs are preferentially maintained such that one copy is 'ancestral' and the other is not. Taken as a whole, the research in this dissertation demonstrates how mathematical modeling can be applied to studying the expression, regulation and evolution of the transcriptome."--Pages ii-iii.
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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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Title: Understanding the intersection of loneliness and recovery setting in older cardiac patients
Creator: Macomber, Catherine A.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Loneliness has significant negative impact on health. Loneliness is the difference between the amount of social support you expect to receive and the amount you perceive you are getting. Age is one risk factor of loneliness, and life events such as a move to a nursing home or the need for professional care to provide assistance with Activities of Daily Living also increase the risk of loneliness. There is little evidence comparing the experience of loneliness between settings of nursing...
Show more"Loneliness has significant negative impact on health. Loneliness is the difference between the amount of social support you expect to receive and the amount you perceive you are getting. Age is one risk factor of loneliness, and life events such as a move to a nursing home or the need for professional care to provide assistance with Activities of Daily Living also increase the risk of loneliness. There is little evidence comparing the experience of loneliness between settings of nursing homes and at home with home care, and yet much current policy sees aging-in-place, staying in your own home, as the most appropriate setting for growing older. This mixed methods study compares the experience of loneliness in two settings, nursing home and at home, and the influence demographics and social support have on this relationship. The theoretical framework used is the Health Belief Model." -- Abstract.
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Title: Enrolling in early college : agency and circumstance in the lives of rural students
Creator: Erfourth, Stavroula S.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Most empirical work on dual enrollment has been quantitative and concerned with issues of demographic participation (minority, first-generation, etc.) and college persistence (Carey, 2015; Cowan, & Goldhaber, 2015; D'Amico, Morgan, Robertson, & Rivers, 2013; Habersham, 2013; McCormick, 2010). Less research, however, has focused on the perspective of the students and how they perceive both their experience in dual enrollment programs and in their schooling and lives leading to the decision to...
Show moreMost empirical work on dual enrollment has been quantitative and concerned with issues of demographic participation (minority, first-generation, etc.) and college persistence (Carey, 2015; Cowan, & Goldhaber, 2015; D'Amico, Morgan, Robertson, & Rivers, 2013; Habersham, 2013; McCormick, 2010). Less research, however, has focused on the perspective of the students and how they perceive both their experience in dual enrollment programs and in their schooling and lives leading to the decision to participate. Fewer studies have concentrated on discovering student motivations for participating and to better understand their experiences (Hudson, 2016; Kanny, 2015; Wallace, 2015; Smith, 2015). As a group, rural students from economically depressed regions have not had the same academic opportunities as their urban and even suburban counterparts (Wallace, 2015; Koricich, 2013; Berg, 2010). By offering early college options, a particular type of dual enrollment program, to these students, school districts and their postsecondary partners can increase the college-going of their communities’ children, and perhaps positively impact the trajectories of lives. However, success of these early college programs is influenced by many things including the foundational development–academic, personal, and social–of the students that attend. To situate my work in this space, using the portraiture method, I sought to expand the limited use of work images and extend it by intersecting the idea with secondary students’ postsecondary choices, specifically as they apply to early college program enrollment. To accomplish this, I employed Emirbayer and Mische’s (1998) theory on human agency and Bronfenbrenner’s (1977) social ecology as a framework to guide questions to students about their decisions to participate in an early college program. I made use of Lawrence-Lightfoot & Davis’ (1997) approach to producing a portrait, which is the product of the aesthetic whole. They believe, In developing the aesthetic whole we come face to face with the tensions inherent in blending art and science, analysis and narrative, description and interpretation, structure and texture. We are reminded of the dual motivations guiding portraiture: to inform and inspire, to document and transform, to speak to the head and to the heart (p. 243). In this work, I offer the portraits of four early college students from a rural, economically disadvantaged area who made the decision to attend college while still in high school and why that decision is valuable for them and the institution they attend.
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Title: Rapid adaptation of floral phenotypes in weedy radish, R.r. Raphanistrum
Creator: Charbonneau, Amanda
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Agricultural weeds cause billions of dollars’ worth of damage worldwide as well as reducing yields, however we often know very little about where they came from, or how they adapt to farming techniques. Agricultural fields are human created environments quite unlike anything in nature and are relatively harsh environments that can exert strong selective pressures. Yearly tilling, for example, likely selects for plants that both quickly reproduce, and can survive in disturbed soils. While some...
Show moreAgricultural weeds cause billions of dollars’ worth of damage worldwide as well as reducing yields, however we often know very little about where they came from, or how they adapt to farming techniques. Agricultural fields are human created environments quite unlike anything in nature and are relatively harsh environments that can exert strong selective pressures. Yearly tilling, for example, likely selects for plants that both quickly reproduce, and can survive in disturbed soils. While some plants with generalist phenotypes might be well suited for thriving in these conditions, others, like Raphanus raphanistrum ssp. raphanistrum (weedy radish), have likely evolved to become weeds. To better understand how these agricultural weeds evolve, I have phenotypically and genotypically characterized weedy R.r. raphanistrum and it’s close relatives. In chapters one and two, I show that weedy R.r. raphanistrum is most closely related to native populations of R.r. raphanistrum, but that these two ecotypes have very different flowering phenotypes. Weedy R.r. raphanistrum flowers in approximately thirty days, while the native plants take fifty to one hundred and fifty days to flower. This demonstrates a likely adaptation to agriculture, and in chapter two I find several loci that may contribute to these phenotypic differences. In chapter three, I analyze differential expression patterns in two selection lines derived from weedy R.r. raphanistrum, to determine genes that underlie differences in floral morphology. These genes should contribute to differences in anther exsertion, which in turn controls how pollen is dispersed onto pollinators. Together, these studies answer basic questions about how evolution works on a short time scale and provide insights into the adaptations of one of the world’s most damaging agricultural weeds. More broadly, these studies demonstrate that weedy radish is a good system for studying rapid evolution in response to both natural and artificial selection and lay the groundwork for future work. In particular, chapters one and two will be useful for broad comparisons across agricultural weeds to determine whether weeds use similar strategies for invading croplands, which would tell us not only about the repeatability of evolution, but also be potentially useful in reducing agricultural losses due to weeds.
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Title: Condensation of phenyl butyl carbinol with phenol in the presence of aluminum chloride
Creator: Bartlett, Jeffrey Hobart, 1900-
Date: 1926
Collection: Electronic Theses & Dissertations

Title: Effect of battery storage technology on the construction of electric vehicle charging stations
Creator: Thakur, Navwant
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Battery storage has become a critical component of electric vehicle (EV) charging infrastructure. However, whether and how battery storage may serve a crucial role in enabling fast-charging stations (FCSs) to fulfill customer demand and provide a profit for charging station operators is unclear. This thesis provides a better understanding of how to construct FCSs with integrated battery storage systems. The work is threefold. First, an in-depth literature review discusses EVs, details the...
Show more"Battery storage has become a critical component of electric vehicle (EV) charging infrastructure. However, whether and how battery storage may serve a crucial role in enabling fast-charging stations (FCSs) to fulfill customer demand and provide a profit for charging station operators is unclear. This thesis provides a better understanding of how to construct FCSs with integrated battery storage systems. The work is threefold. First, an in-depth literature review discusses EVs, details the types of charging stations and standards, and evaluates battery technologies. The review indicates that lithium-ion batteries are most promising for charging station applications followed by lead-acid and vanadium-redox batteries. Second, processes and considerations for installation of an FCS and battery storage unit are conducted. The results provide a cost estimation for various configurations of FCSs and battery storage costs based on battery size, type, and vendor. Third, a discrete event simulation (DES) model is developed to evaluate battery storage costs and characteristics for a network of FCSs in Southeast Michigan. The simulation finds that when considering network costs (i.e., the cost of setting up a new distribution line), no exchange of energy occurs and each of the FCSs requires more than one battery. When network costs are not considered, less exchange of energy occurs, and two-thirds of the FCSs require a battery. For this network, lithium-ion batteries cost the most whereas zinc-air batteries cost the least. Owing to high network costs, a highly condensed FCS network would provide higher benefit and result in lower total cost through battery units connected to a microgrid. This model is useful to stakeholders in this area (e.g., charging station operators, battery manufacturers, and vendors) to evaluate the battery costs and characteristics that fit their FCS network best."--Page ii.
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