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Title: A fertilization experiment with rhubarb
Creator: Benson, Edward Byron
Date: 1917
Collection: Electronic Theses & Dissertations

Title: A finite element study of human thigh area in seated posture for pressure ulcer prediction and prevention
Creator: Chen, Sheng
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Pressure ulcers (PUs), also known as pressure sores, are localized damage to the skin and underlying tissues, usually occurring over a bony prominence and caused by sitting or lying in one position for long time. PUs are a detriment to the well-being of people who lose their mobility either permanently or temporarily, and high morbidity and mortality are associated with PUs. Although the initiating mechanism of PUs is still unclear, it is commonly accepted that internal normal and shear...
Show morePressure ulcers (PUs), also known as pressure sores, are localized damage to the skin and underlying tissues, usually occurring over a bony prominence and caused by sitting or lying in one position for long time. PUs are a detriment to the well-being of people who lose their mobility either permanently or temporarily, and high morbidity and mortality are associated with PUs. Although the initiating mechanism of PUs is still unclear, it is commonly accepted that internal normal and shear stresses, due to the presence of unrelieved external loads, play a central role in the formation and development of these wounds. Despite the significance of internal stresses in PUs formation, interfacial pressures, which are a surface measure of stress, are the indicators commonly used to develop practices and protocols to minimize loading on the soft tissue. However, no direct correlation exists between interfacial pressure and internal stresses of soft tissue. Therefore, tools and methods that can show internal distributions of soft tissue's stresses and strains as a response to external loading are needed.The ability of finite element (FE) models to accurately represent the anatomical structure of the leg and buttocks area and to estimate the localized stress/strain fields within highly deformable media, makes them powerful tools to investigate soft tissue response to external loadings. Despite the significant advancement previous studies have achieved, there are still important aspects in human thigh-buttock soft tissue modeling area that need to be improved. Two challenges are identified in this dissertation: 1) Microstructurally motivated skin modeling for an individual skin layer in finite element model. 2) Parameters estimation associated with large deformations.To address the first challenge, a microstructurally based constitutive model is proposed to describe the mechanical behavior of skin. The constitutive model incorporated the distribution of collagen fiber bundle orientations and relative collagen content measured from histology, and shows good agreement with the tensile test data.To address the second challenge, an optimization procedure that is able to match nonlinear behaviors between FE simulation and in vivo experimental data is developed. The difference between 3D and semi-3D model is quantified, and the accuracy of four commonly used constitutive model representing soft tissue nonlinear mechanical behavior is compared.Finally, a thigh FE model that has detailed anatomical representation of different soft tissue types, i.e., skin, fat, and muscle, is developed. The subject-specific in vivo experimental data are used to inform the optimization procedure to obtain best-fit constitutive parameters for different soft tissue types. The research in this dissertation provides an approach to describe the in vivo mechanical behavior of soft tissues in thigh-buttock area accurately through FE modeling. The constitutive parameters informed by in vivo data in this dissertation are valuable to facilitate future FE modeling studies to achieve accurate internal stress/strain distribution of soft tissues in thigh-buttock area.
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Title: A forest planting in Michigan
Creator: Haines, Paul B.
Date: 1914
Collection: Electronic Theses & Dissertations

Title: A general test of the Otis elevator installed in the R.E. Olds hall of engineering
Creator: Collins, Glenn C.
Date: 1917
Collection: Electronic Theses & Dissertations

Title: A genomic investigation of Marek's disease lymphomas
Creator: Steep, Alexander Cordiner
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "Meq, a bZIP transcription factor and the viral oncogene for pathogenic strains of Marek's disease virus (MDV), is required to induce CD4 T cell lymphomas that characterize Marek's disease (MD) in chickens. However, Meq is not sufficient for neoplastic transformation as not all birds infected with pathogenic strains of MDV developed Marek's disease. We hypothesize that additional drivers or somatic mutations in the chicken genome are required for MDV-induced transformation. Using and...
Show more"Meq, a bZIP transcription factor and the viral oncogene for pathogenic strains of Marek's disease virus (MDV), is required to induce CD4 T cell lymphomas that characterize Marek's disease (MD) in chickens. However, Meq is not sufficient for neoplastic transformation as not all birds infected with pathogenic strains of MDV developed Marek's disease. We hypothesize that additional drivers or somatic mutations in the chicken genome are required for MDV-induced transformation. Using and integrating DNA and RNA genomic screens of Marek's disease tumors from genetically-defined experimental layers, our analyses reveal 0.3 somatic mutations per megabase consisting primarily of somatic single nucleotide variants (SNVs) and small insertions and deletions (Indels). Somatic deletions, insertions, and point mutations were enriched in IKZF1 (Ikaros), the first driver gene of Marek's disease lymphomas. Ikaros, a Zn-finger transcription factor and the master regulator of lymphocyte development, is a known tumor suppressor in human and murine acute leukemias and lymphomas. In our surveyed Marek's disease tumors, 41% of the samples had somatic mutations in key N-terminal Zn-finger binding domains, strongly suggesting perturbed Ikaros function in its ability to bind DNA and regulate transcription. Somatic mutations in IKZF1 were preferentially found in tumors of gonadal tissues as well as their metastatic clones. IKZF1 mutant Marek's disease tumors revealed gene expression profiles indicative of Ikaros perturbation. In addition to IKZF1, other putative somatic mutations reside in ZNF384, EFNA5, CLDND1, FOXD1, ROBO1, and ROBO2 and warrant evaluation. Our results suggest MDV-induced tumors are driven by both Meq expression and IKZF1 somatic mutations that in combination lead to unregulated proliferation, increased cell adhesion, increased migration, and dedifferentiation."--Pages ii-iii.
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Title: A geometry based approach towards improving the structural integrity of single-walled ti6al4v alloy features fabricated using laser directed energy deposition additive manufacturing
Creator: Thakkar, Darshan
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Presence of sharp turns in the deposition tool-path for Additive Manufacturing (AM) introduces heterogeneity in built-part thereby affecting structural integrity. Slower deposition speeds around turn points or corner leads to defects such as increased wall thickness, porosity, lack of fusion voids, and cracks. Such defects can be minimized by either by optimizing processing parameters or through geometry optimization. Optimizing processing parameters requires extensive and expensive set of...
Show morePresence of sharp turns in the deposition tool-path for Additive Manufacturing (AM) introduces heterogeneity in built-part thereby affecting structural integrity. Slower deposition speeds around turn points or corner leads to defects such as increased wall thickness, porosity, lack of fusion voids, and cracks. Such defects can be minimized by either by optimizing processing parameters or through geometry optimization. Optimizing processing parameters requires extensive and expensive set of experiments. Furthermore, it is challenging to accurately model the process and have closed loop controls because of the impracticality to include all process parameters. This work focuses on optimizing the geometry instead of process parameters to fabricate components with minimum defects. In this work, single walled cubical Ti6Al4V shells with sharp and rounded corners were fabricated using laser Directed Energy Deposition (DED). Cross sectional and build plane coupons were extracted from each sample for microstructure and defect analysis. Results show that inclusion of rounded corners leads to consistent deposition speeds. Defect density measurements, using optical microscope, show reduction of defects from 6.8 ± 0.35% to a virtually defect-free structure for samples with rounded corners. Results indicate that consistent deposition speed around rounded corners improved homogeneity in the resulting microstructure.
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Title: A global modeling framework for plasma kinetics : development and applications
Creator: Parsey, Guy Morland
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The modern study of plasmas, and applications thereof, has developed synchronously with com-puter capabilities since the mid-1950s. Complexities inherent to these charged-particle, many-body, systems have resulted in the development of multiple simulation methods (particle-in-cell,fluid, global modeling, etc.) in order to both explain observed phenomena and predict outcomesof plasma applications. Recognizing that different algorithms are chosen to best address specifictopics of interest, this...
Show moreThe modern study of plasmas, and applications thereof, has developed synchronously with com-puter capabilities since the mid-1950s. Complexities inherent to these charged-particle, many-body, systems have resulted in the development of multiple simulation methods (particle-in-cell,fluid, global modeling, etc.) in order to both explain observed phenomena and predict outcomesof plasma applications. Recognizing that different algorithms are chosen to best address specifictopics of interest, this thesis centers around the development of an open-source global model frame-work for the focused study of non-equilibrium plasma kinetics. After verification and validationof the framework, it was used to study two physical phenomena: plasma-assisted combustion andthe recently proposed optically-pumped rare gas metastable laser.Global models permeate chemistry and plasma science, relying on spatial averaging to focusattention on the dynamics of reaction networks. Defined by a set of species continuity and energyconservation equations, the required data and constructed systems are conceptually similar acrossmost applications, providing a light platform for exploratory and result-search parameter scan-ning. Unfortunately, it is common practice for custom code to be developed for each application-an enormous duplication of effort which negatively affects the quality of the software produced.Presented herein, the Python-based Kinetic Global Modeling framework (KGMf) was designed tosupport all modeling phases: collection and analysis of reaction data, construction of an exportablesystem of model ODEs, and a platform for interactive evaluation and post-processing analysis. Asymbolic ODE system is constructed for interactive manipulation and generation of a Jacobian,both of which are compiled as operation-optimized C-code.Plasma-assisted combustion and ignition (PAC/PAI) embody the modernization of burning fuelby opening up new avenues of control and optimization. With applications ranging from engineefficiency and pollution control to stabilized operation of scramjet technology in hypersonic flows,developing an understanding of the underlying plasma chemistry is of the utmost importance.While the use of equilibrium (thermal) plasmas in the combustion process extends back to the ad-vent of the spark-ignition engine, works from the last few decades have demonstrated fundamentaldifferences between PAC and classical combustion theory. The KGMf is applied to nanosecond-discharge systems in order to analyze the effects of electron energy distribution assumptions onreaction kinetics and highlight the usefulness of 0D modeling in systems defined by coupled andcomplex physics.With fundamentally different principles involved, the concept of optically-pumped rare gasmetastable lasing (RGL) presents a novel opportunity for scalable high-powered lasers by takingadvantage of similarities in the electronic structure of elements while traversing the periodic ta-ble. Building from the proven concept of diode-pumped alkali vapor lasers (DPAL), RGL systemsdemonstrate remarkably similar spectral characteristics without problems associated with heatedcaustic vapors. First introduced in 2012, numerical studies on the latent kinetics remain immature.This work couples an analytic model developed for DPAL with KGMf plasma chemistry to bet-ter understand the interaction of a non-equilibrium plasma with the induced laser processes anddetermine if optical pumping could be avoided through careful discharge selection.
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Title: A graphical solution of the short transmission line problem
Creator: Andrews, Francis E.
Date: 1918
Collection: Electronic Theses & Dissertations

Title: A livelihood and systems-based approach for understanding drivers of adoption and disadoption of organic farming in Ibadan, Nigeria
Creator: Adebiyi, Jelili Adegboyega
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "Livelihood challenges such as low income, food insecurity, and poverty are prevalent among farming and rural communities in sub-Saharan Africa (SSA) and are linked to low agricultural productivity. Boosting agricultural productivity is considered pivotal to improving the livelihood conditions of farming and rural communities in SSA. Some non-governmental stakeholders and international development agencies promote organic agriculture as a pro-poor strategy to help enhance agricultural...
Show more"Livelihood challenges such as low income, food insecurity, and poverty are prevalent among farming and rural communities in sub-Saharan Africa (SSA) and are linked to low agricultural productivity. Boosting agricultural productivity is considered pivotal to improving the livelihood conditions of farming and rural communities in SSA. Some non-governmental stakeholders and international development agencies promote organic agriculture as a pro-poor strategy to help enhance agricultural productivity and farmers' livelihoods conditions in SSA. For reasons yet to be well-understood, the adoption rates of organic farming by smallholder farmers in SSA is low. To fill these gaps, in three essays, this dissertation investigated the barriers and the factors that influence and gender the adoption of first-party certified organic leafy vegetable production (OLVP) by smallholder farmers in Ibadan, southwestern Nigeria. First, we developed a gender-aware and livelihood-based conceptual framework named TALAF, which was used to inform the second and third essays. The first essay qualitatively examined the factors that influence, inhibit and gender the adoption of OLVP. The second essay investigated the factors and contexts that motivated disadoption of OLVP in the study areas in order to generate insights about what can be done to avert or stem the phenomenon. The third essay combined participatory causal loop diagraming with network analysis to map and contrast the similarities and differences in the causal mechanisms that dynamically interact to affect the adoption of organic farming in urban and rural Nigeria. As a whole, the dissertation contributes to the literature on the adoption, disadoption and gendering of organic farming in Nigeria and Africa. Through TALAF, the dissertation offers a conceptual framework that can help untie the complexity in technology adoption decision-making contexts."--Page ii.
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Title: A macrosporium leaf spot disease of red clover
Creator: Krakover, Leo J.
Date: 1915
Collection: Electronic Theses & Dissertations

Title: A meditation on loss within games
Creator: Tokarski, Justin C.
Date: 2016
Collection: Electronic Theses & Dissertations
Description: "Failure is something which we are all familiar with, but when we look at games and the rules which govern them failure takes on a different form. This kind of failure, unique to games, is what I term Loss. To be truly unique to games, Loss must be the result of gamic actions taken by the player, must be constrained by the limitations of the game, and must represent a unique occurrence or state within the game. Taking these constraints into account I propose the following as a definition of...
Show more"Failure is something which we are all familiar with, but when we look at games and the rules which govern them failure takes on a different form. This kind of failure, unique to games, is what I term Loss. To be truly unique to games, Loss must be the result of gamic actions taken by the player, must be constrained by the limitations of the game, and must represent a unique occurrence or state within the game. Taking these constraints into account I propose the following as a definition of Loss. Loss is a player state in a game, entered into when a 'Loss Condition' has been met by the direct actions of the player, wherein something valued by the player within the game is removed. This definition, upon inspection, leads to several different and unique aspects, or dimension, of Loss which provide useful tools for understanding, analyzing, and creating Loss within games. The Digital Dimension of Loss consists of the binary triggers, Loss Conditionals, which lead the game to enter a State of Loss. The Design Dimension of Loss is the method of translating Loss Conditionals into unique game events understandable to the player. The Value Dimension of Loss consists of the gamic measures of effort that are taken away from the player by Loss. Finally, the Experience Dimension of Loss concerns the subjective effects of Loss on the player and methods for predicting what these effects will be. Together, this definition and the 4 aspects of Loss provide us new tools for understanding Loss as unique to games and distinct from failure in non-game contexts."--Page ii.
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Title: A method for determining seed viability by electrical conductivity measurements
Creator: Fick, George L.
Date: 1924
Collection: Electronic Theses & Dissertations

Title: A method of relay protection for the power network of the Ohio Edison company
Creator: Dausman, Orin D.
Date: 1927
Collection: Electronic Theses & Dissertations

Title: A microscopic examination of wool
Creator: Bulkeley, Joseph A.
Date: 1899
Collection: Electronic Theses & Dissertations

Title: A minimalistic data distribution system to support uncertainty-aware GIS
Creator: Ronnei, Nicholas Oren
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Error and uncertainty are inherent in all digital elevation models (DEMs) - representations of the Earth's terrain. It is absolutely essential to account for this uncertainty in any GIS operations that rely on this data because uncertainty propagates through any derived products. This can have very serious consequences such as the potential invalidation of model results. Geostatistical methods like conditional stochastic simulation have been developed to mitigate this problem, but they...
Show moreError and uncertainty are inherent in all digital elevation models (DEMs) - representations of the Earth's terrain. It is absolutely essential to account for this uncertainty in any GIS operations that rely on this data because uncertainty propagates through any derived products. This can have very serious consequences such as the potential invalidation of model results. Geostatistical methods like conditional stochastic simulation have been developed to mitigate this problem, but they require expert knowledge to apply them to a project. Despite the fact that uncertainty propagation has been discussed in geographic literature for nearly three decades, there has been very little progress in making such analysis accessible to those who are not geostatistics experts--the majority of GIS users. This research uses open source software to build a system that makes the results of complex error models accessible to researchers worldwide without the need for expert knowledge. Then, I use this system to acquire data and perform a basic analysis, demonstrating how the average researcher might incorporate uncertainty propagation in own their work. In doing so, I hope to elucidate the ways in which conditional stochastic simulation changes the traditional spatial data model and set an example for others to follow. -- Abstract.
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Title: A mixed-method study of friendship networks and psychological and sociocultural adaptation among chinese international undergraduates in u.s. higher education
Creator: Xie, Mingjun
Date: 2019
Collection: Electronic Theses & Dissertations
Description: In recent years, U.S. colleges and universities have observed a rapid expansion of the enrollment of international students. Particularly Chinese students, the largest group of international students since 2010, have increased nearly threefold in just eight years (Institute of International Education, 2010-2018). Prior studies have investigated the friendship networks of international students (Rose-Redwood & Rose-Redwood, 2013) and the influence of peer relations on international students'...
Show moreIn recent years, U.S. colleges and universities have observed a rapid expansion of the enrollment of international students. Particularly Chinese students, the largest group of international students since 2010, have increased nearly threefold in just eight years (Institute of International Education, 2010-2018). Prior studies have investigated the friendship networks of international students (Rose-Redwood & Rose-Redwood, 2013) and the influence of peer relations on international students' cross-cultural adaptation (Hendrickson, Rosen, & Aune, 2011). However, the extant literature has largely neglected to examine international students' lived experiences of establishing friendship networks and the underlying mechanism of the associations between friendships and international student adaptation. Guided by social capital theory (Lin, 1999) and acculturation process framework (Ward, Bochner, & Furnham, 2001), the purpose of my dissertation is to examine Chinese students' peer interaction patterns and how friendships influence their psychological well-being and sociocultural adjustment.My dissertation consists of two studies. The first study drew upon two waves of surveys collected with 46 Chinese students (30 females, Mage = 18.89, SD = .80) and multiple in-depth interviews conducted with five students (three females, Mage = 18.40, SD = .89). The results yield three main findings. First, Chinese students of the present study nominated predominant Chinese friends, much more than domestic and other international student friends, in both waves. Second, Chinese students did not necessarily develop more diverse, integrated friendship networks over time. Specifically, more than half of the participants nominated Chinese friends only in both waves, possibly because of language barriers and prior discrimination experiences. Lastly, the interview findings illustrated that Chinese students' engagement in college settings shaped their experiences of building friendship networks, such that greater engagement in meaningful common experiences (such as club activities, religious groups, and experiences of working together) could facilitate cross-cultural interaction between Chinese students and domestic students.Guided by social capital theory (Lin, 1999) and acculturation process framework (Ward, Bochner, & Furnham, 2001), the second study examined: (1) how friendship networks, specifically the national backgrounds of nominated friends, the frequency of contact, and the intimacy of friendships, are associated with psychological and sociocultural adaptation among Chinese undergraduates (N = 273, Mage = 19.18, SD = .84) in U.S. higher education; and (2) the role of social connectedness as a mediator. Results indicated that compared to superficial relationships, high-quality peer interaction (for example, friendships involving both frequent contact and intimacy) might be a key to bolster Chinese students' ability to navigate cross-cultural challenges. Further, social connectedness mediated the associations between friendships and student adaptation, such that frequent and intimate interaction with domestic students was associated with greater social connectedness and, in turn, better psychological and sociocultural adaptation. The findings point to practical implications for the host institutions, especially for universities enrolling large numbers of international students. It is important for the host institutions to develop corresponding programs to facilitate social opportunities for different groups to mingle and establish sustained friendships.
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Title: A model poultry house for fifty hens
Creator: Krentel, Christian M.
Date: 1899
Collection: Electronic Theses & Dissertations

Title: A new paradigm for generating surface-normal forces for hull-cleaning robots
Creator: Kamensky, Kristina Maria
Date: 2020
Collection: Electronic Theses & Dissertations
Description: A Bernoulli pad uses an axial jet to produce radial outflow between the pad and a proximally located parallel surface, which may be either a mobile workpiece or a fixed wall. The flow field produces a force between the surfaces which depends upon their spacing h. The direction of this force is repulsive for large and small h, but two equilibria exist between these limits. The nearer equilibrium point (heq) is stable, and this distance is dependent on the direction and magnitude of the force...
Show moreA Bernoulli pad uses an axial jet to produce radial outflow between the pad and a proximally located parallel surface, which may be either a mobile workpiece or a fixed wall. The flow field produces a force between the surfaces which depends upon their spacing h. The direction of this force is repulsive for large and small h, but two equilibria exist between these limits. The nearer equilibrium point (heq) is stable, and this distance is dependent on the direction and magnitude of the force the pad is required to apply. Increasing the flow rate increases the strength of the contactless grip, subject to cavitation or compressibility constraints, depending on the working fluid. Industry has created devices of this type to grip and transport a variety of workpieces without contact. The present research is inspired by the need to keep a submerged ship hull free of biofouling organisms. Preventative maintenance during idle periods of operations can improve efficiency while prolonging the original surface properties of the hull. The Bernoulli pad for this application is significantly larger and uses the surrounding water as the working fluid. In the present work, the flow field was investigated computationally and experimentally. Field tests were also performed to determine the ability of the device to mitigate biofouling. The computational work, which was validated with experimental results found in literature, indicates that a power-law relationship exists between heq and the inlet fluid power required to sustain this equilibrium spacing when each is appropriately scaled. This scaling is derived principally from the wall shear; an additional term incorporating the inlet Reynolds number is used to account for the force applied to the system. The relationship is valid over a range of forces acting on the system, geometric, and material properties. Major and minor geometry alterations provide insight to customizing pressure or wall shear stress profiles.The biofouling removal ability of a shear-based device was field tested on two submerged surface types, Garolite G-10 and AkzoNobel's Intersleek 1100SR. The latter is a fouling-release coating. Each surface was groomed at four frequencies along with a control group during a seven-week grooming study conducted in Narragansett Bay in Rhode Island. An image-processing algorithm was developed and used to assess the effectiveness of the various grooming protocols, along with direct measurements of chlorophyll a per surface area. The image-processing data showed that the grooming resulted in approximately 50% cleanliness on the Garolite at the end of the study whereas the Intersleek was continuously restored to nearly its initial clean state. Chlorophyll a data supported these overall conclusions. These results indicate that surface cleanliness can be maintained effectively on Intersleek using frequent shear-based grooming. The key to success is to match or supersede the critical wall shear stress of settled biofouling organisms whose adhesive strength is exponential in time.Particle Tracking Velocimetry (PTV) measurements were also taken on the flow field. This Lagrangian measurement approach uses an iterative particle reconstruction technique in combination with high seeding density to reconstruct a 4D (x, y, z, t) flow field. This 4D reconstruction allows the pressure field to be reconstructed using the Navier-Stokes equations. Various experiments have been conducted on confined radial outflow but PTV measurements are presented here for the first time. The PTV measurements were compared with computational results and while there is reasonable agreement in the velocity field data, there are discrepancies is the pressure field data. Recommendations are provided for future work that can reconcile these differences.
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Title: A new type of radio vacuum tube
Creator: Park, Chauncey M.
Date: 1925
Collection: Electronic Theses & Dissertations

Title: A physical and micrographical study of carbon steels
Creator: Aronson, Arthur V.
Date: 1921
Collection: Electronic Theses & Dissertations

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