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Title: DEPRESSION AND ATTRIBUTIONS FOR DISTRESS
Creator: Hanson, Bjorn J.
Date: 2013, 2013-07
Description: Distress caused by depressive symptoms includes both direct and mediated pathways. Attributions for distress in individuals suffering from...
Show moreDistress caused by depressive symptoms includes both direct and mediated pathways. Attributions for distress in individuals suffering from depressive symptoms represent indirect pathways that have a high potential to be modified by psychotherapeutic interventions; however, little research has focused on the content of these attributions. This study provides the first quantitative measurement of this reasons-for-distress paradigm. Specifically, we aim to describe the frequencies, intensities, and co-occurrence patterns of attributions for distress, as well as distinguish the attributions for distress paradigm from previous attributions for depression research. Furthermore, we seek to demonstrate the accuracy of an illness behavior model for conceptualizing distress caused by depressive symptoms by differentiating symptom severity from symptom distress. In addition to quantifying attributions for distress, this study also extends previous research regarding rumination, the severity of distress caused by cognitive and vegetative symptoms of depression, and the co-occurrence of specific symptoms and specific reasons for distress. Individuals currently suffering from depressive symptoms were recruited from web-based advertisements to participate in this cross-sectional, online self-report study. A total of 204 individuals qualified for the study and completed some portion of the Reasons for Distress Questionnaire-Depression (RDQ-D). Results demonstrated that all reasons provided as part of the RDQ-D represented common attributions for distress in depressed individuals. Reasons related to personalized reasons for distress (Other), long-term outcomes (Long-term Consequences), productivity impairment (Work and Productivity Impairment), and x existential distress (Lack of Purpose or Meaning) were rated as significantly more distressing when compared with all reasons for distress. Cluster analysis suggested that certain reasons tended to co-occur and that some attributions for distress are nearly universal amongst individuals suffering from significant depressive symptoms. The reason-for-distress paradigm was demonstrated to be related to, yet distinct from, the reason-for-depression paradigm (Addis, Truax, & Jacobson, 1995). Distress ratings were also found to be moderately positively correlated with some depressive symptoms, but not others, providing support for an illness behavior conceptualization of distress severity in depression. Expanding on prior research, results showed that rumination was equally distressing and frequent across gender. Also, cognitive/affective symptoms of depression were rated as more distressing than vegetative symptoms of depression. Additionally, participants demonstrated the capacity to endorse specific reasons for distress in association with specific symptoms. As predicted, the existential reason for distress Lack of Purpose or Meaning was endorsed more frequently in relation to cognitive/affective symptoms of depression as compared to vegetative symptoms of depression. By focusing on specific symptoms of depression, the RDQ-D provides a clinical assessment that has the ability to identify specific unhelpful responses to symptoms that may be causing distress in addition to that inherent in the experience of the symptom. These unhelpful responses can then be included in case conceptualization, treatment planning, and intervention selection.
PH.D in Psychology, July 2013
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Title: COMPUTER AIDED DIAGNOSIS IN MAMMOGRAPHY WITH CONTENT-BASED IMAGE RETRIEVAL
Creator: Jing, Hao
Date: 2011-11, 2011-12
Description: Computer-aided diagnosis (CAD) for breast cancer, a common form of cancer in women, has been an active research area. This work aims to...
Show moreComputer-aided diagnosis (CAD) for breast cancer, a common form of cancer in women, has been an active research area. This work aims to investigate and develop CAD techniques for clustered microcalcifications (MCCs), which can be an important early sign of breast cancer. The contributions of this work include development of a database of cancer cases and algorithms for detection and classification of MCCs. First, a database consisting of a large number of cases is built from different sources. To support the merging of cases from different data sources, a feature comparison study is conducted between mammograms from screen film and full field digital mammography (FFDM) systems. It is demonstrated that the features extracted from film and FFDM are highly correlated and there is no adverse effect on a CAD task of classification when used together. Second, a spatial point process (SPP) approach is proposed to exploit the spatial distribution among different MCs in a mammogram directly during the detection process. This is different from the conventional approach in which detection algorithms are employed to first identify individual MCs in a mammogram, which are subsequently grouped into clusters by a clustering algorithm. The performance of the proposed approach is demonstrated to be superior to an existing method based on the support vector machine (SVM). Third, in observation of the emerging of large databases from the picture archiving and communication (PAC) systems in the clinics, a retrieval driven approach is proposed for classification of MCCs. In this approach, for a case to be diagnosed (i.e., query), a set of similar cases is retrieved from a database and subsequently is used to train xii an adaptive classifier specifically for the query case using the technique of logistic regression. The proposed approach is demonstrated to lead to significant improvement in classification accuracy. Moreover, the proposed adaptive classification approach is further developed using regularization techniques, where a prior is first derived from a baseline classifier and then used to regularize the adaptive classifier trained with the retrieved cases. The regularized adaptive classifier can be more computationally efficient, and is demonstrated to achieve further improvement in performance.
Ph.D. in Electrical Engineering, December 2011
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Title: INTERACTION OF DAIRY BASED PROTEIN WITH PHENOLIC ANTIOXIDANT OF STRAWBERRY POWDER
Creator: Feng, Haoshi
Date: 2012-05-04, 2012-05
Description: Fruits contain an abundant amount of polyphenolic compounds that have antioxidant properties. These compounds have shown the ability of...
Show moreFruits contain an abundant amount of polyphenolic compounds that have antioxidant properties. These compounds have shown the ability of reducing the risk of major degenerative diseases, relief from allergies/asthma, weight loss and improved circulation. Dairy proteins have numerous benefits as enhancing muscle formation, weight and blood pressure control, beneficial effect in bone and dental health and protection against toxins, bacteria, and viruses. The combination of both fruit and dairy in commercial or homemade mixtures, such as smoothies, is readily available and popular. But in fact, the interactions which happen between proteins and fruit antioxidants could affect the availability and potential activity of antioxidants. This thesis will focus on the interaction of dairy proteins with antioxidant from freeze dried strawberry and measure the availability of the antioxidant capacity. Freeze dried strawberry powder at different concentrations (1.64%, 3.28% and 6.56%) was mixed with four types of proteins at different concentration to demonstrate the interaction over a range. The proteins used were skim milk powder (6.89%), whey from bovine milk (0.51%), casein from bovine milk (2.04%), and albumin from bovine serum (2.55%). The antioxidant content was measured by several analytical techniques using LCMS/MS, Oxygen Radical Absorbance Capacity (ORAC) assay and Folin-Ciocalteu assay. SDS-PAGE was used to examine the change of protein molecular weight before and after the reactions. The binding interaction resulted in significantly reduced ORAC and Folin- Ciocalteu assay values compared to the respective non-protein strawberry mixtures (P<0.001 and P<0.05). The SDS-PAGE images between protein strawberry mixtures and non-protein strawberry mixtures showed similar results. The (+)-catechin, cyanidin-3-O glucoside, pelargonidin-3-O-glucoside and kaempferol-3-coumaroylglucoside content were significantly reduced when comparing skim milk based strawberry powder mixtures and non-protein strawberry mixtures (P<0.05). This research indicates the binding interaction between dairy protein and freeze dried strawberry powder reduces the antioxidant activity of the freeze dried strawberry powder.
M.S. in Food Safety and Technology, May 2012
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Title: MEASUREMENT OF INTRARETINAL NITRIC OXIDE IN EARLY DIABETIC RETINOPATHY
Creator: Guthrie, Micah
Date: 2014, 2014-12
Description: Diabetic retinopathy (DR) is the most frequent cause of new cases of blindness among adults aged 20-74 years. Nearly all patients with Type 1...
Show moreDiabetic retinopathy (DR) is the most frequent cause of new cases of blindness among adults aged 20-74 years. Nearly all patients with Type 1 diabetes and greater than 60% of patients with Type 2 diabetes will develop retinopathy within the rst two decades of the disease. Nitric oxide (NO) has been shown to play a role in the progression of DR, contributing to neuronal dysfunction and the breakdown of the blood-retina barrier early stages of the disease. The objective of the current study was to investigate the changes in intraretinal NO levels in early DR. To accomplish this, a dual NO/electroretinogram (ERG) electrode was developed to make the rst direct measurements of NO concentration throughout the in vivo retina. These electrodes were validated in an in vivo animal model by comparing control recordings to those taken after injection of the broad spectrum nitric oxide synthase (NOS) inhibitor L-NG-Nitroarginine methyl ester (L-NAME). Control NO pro les showed high levels of NO in the photoreceptor layer with localized areas of increased NO in the amacrine/ganglion cell layer. L-NAME NO pro les showed substantially reduced NO in the retina, indicating that the electrodes were measuring actual NO. The electrodes were then used to record NO pro les from the retinas of rats made diabetic with streptozotocin (STZ). The recordings were obtained three weeks after injection of STZ. Blood glucose levels were also monitored in order to correlate the blood glucose level with intraretinal NO concentration. It was found that mild diabetic rats (blood glucose 250-400 mg/dL) had higherthan- control levels of NO throughout their retinas. Severe diabetics (500-600 mg/dL) had lower-than-control levels, while moderate diabetics (400-500 mg/dL) did not have signi cantly di erent NO levels than controls. The NO pro les from the severe diabetics were very similar to L-NAME pro les, indicating that NOS production may be abnormal in severe diabetics. It was also found that intraretinal NO concentration was inversely correlated with the blood glucose of diabetic rats. To determine if the changes in NO seen in diabetic rats were due to direct tissue exposure to high glucose, NO pro les were also recorded from rats acutely injected with glucose solution to achieve similar levels of hyperglycemia. No changes in NO levels were seen in the retinas of these acute hyperglycemic rats, indicating that there are other factors besides high glucose contributing to the NO changes in DR. The results show that there is not a simple increase in NO as severity of diabetes increases and highlight the importance of being able to make measurements of bioavailable NO in retinal tissue. The electrodes were able to detect clear di erences in experimental DR, indicating their utility in investigating NO changes in the early stages of the disease. Future work with the electrodes needs to be performed to investigate the mechanisms of NO changes in DR in order to develop potential treatments which could mitigate the damage at an early stage before vision loss occurs.
M.S. in Biomedical Engineering, December 2014
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Title: HIV-RELATED TRAUMA AND ANTIRETROVIRAL ADHERENCE: THE EFFECTS OF PERSONAL RESOURCES
Creator: Guy, Arryn A.
Date: 2017, 2017-05
Description: Suboptimal adherence to antiretroviral therapy (ART) can interfere with virologic suppression and increase risk of developing drug-resistant...
Show moreSuboptimal adherence to antiretroviral therapy (ART) can interfere with virologic suppression and increase risk of developing drug-resistant strains of the virus. People living with HIV (PLH) have difficulty complying with ART—a treatment regimen that is unforgiving of non-adherence—in large part because this population is at higher risk for stressors, including experiencing their HIV diagnosis as a traumatic event (e.g., Boarts et al., 2006; Theuninck, Lake, & Gibson, 2010). Perceived social support and coping are contextual and changeable factors that can be focused on in interventions to improve treatment adherence. This study aimed to confirm that more perceived social support is related to optimal treatment adherence in PLH who experienced HIV-related trauma, through bolstering coping strategies, namely, emotion-focused coping strategies like positive reappraisal and emotional social support seeking, and problem-focused coping related to managing ART (i.e., active coping). Participants were 62 young adults living with HIV recruited from a local HIV clinic. Participants were assessed for experiencing their HIV diagnosis as a traumatic event, perceived social support, coping, and medication adherence. Positive reappraisal, emotional support seeking, and active coping strategies did not mediate the relation between perceived social support and adherence, however, active coping had a statistically significant effect on adherence when controlling for other hypothesized mediators in the model. This finding has practical significance for clinicians in that it suggests active coping plays a more direct role in improving treatment adherence than emotional support seeking and positive reappraisal coping strategies.
M.S. in Psychology, May 2017
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Title: TOWARD A NATURAL GENETIC/EVOLUTIONARY ALGORITHM FOR MULTIOBJECTIVE OPTIMIZATION
Creator: Ramasamy, Hariharane
Date: 2013, 2013-05
Description: Practical optimization problems often have multiple objectives, which are likely to conflict with each other, and have more than one optimal...
Show morePractical optimization problems often have multiple objectives, which are likely to conflict with each other, and have more than one optimal solution representing the best trade-offs among the competing objectives. Genetic algorithms, which optimize by repeatedly applying genetic operators to a population of possible solutions, have been used recently in multiobjective optimization, but often converge to a single solution that is not necessarily optimal due to lack of diversity in the population. Current multiobjective genetic and other evolutionary methods prevent this premature convergence by promoting new members that are dissimilar in parameter or objective space. A distance measure, which calculates similarities among the members in either objective or parameter space, is used to degrade the fitness of solutions when they are crowded in a small region. This process forces the algorithm to find new but distinct trade-off points in the objective or parameter space, but is computationally expensive. As the number of objectives or parameters increases, the methods fail to scale up and they deviate from the motivating concept of the genetic algorithm—natural evolution. We extend the standard genetic algorithm through two simple, yet powerful, changes motivated by natural evolution. In the first method, the algorithm, at each step, randomly or sequentially chooses one of the objectives for optimization; hence the method is called sequential extended genetic algorithm (SEGA). In the second method, a population is maintained for each objective, and crossover is performed selecting parents from across populations. This method is called parallel extended genetic algorithm (PEGA). We applied these methods to test problems from the literature, and to two well known problems, protein folding and multiple knapsack. We discovered our methods found better trade-off solutions than current multiobjective methods, without increasing computational complexity of genetic algorithms.
PH.D in Computer Science, May 2013
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Title: EFFICACY OF PULSED LIGHT TECHNOLOGY FOR THE INACTIVATION OF SALMONELLA ENTERITIDIS PT 30 ON ALMOND KERNEL SURFACE
Creator: Harguindeguy, Maite
Date: 2016, 2016-05
Description: Almond surfaces can be contaminated with pathogens such as Salmonella. Traditional thermal processing technologies used for inactivation of...
Show moreAlmond surfaces can be contaminated with pathogens such as Salmonella. Traditional thermal processing technologies used for inactivation of Salmonella on almonds can adversely impact the quality. Therefore, there is a need to investigate the efficacy of alternative technologies for inactivation of Salmonella on almonds without adversely affecting the quality. Pulsed light, a novel technology, can potentially be used to achieve this. Therefore, this study evaluated the efficacy of three pulsed light systems (operating at 1.8, 3, or 100 Hz) under various electrical input powers (1000, 1250 and 1500 W) and treatment times for inactivation of Salmonella Enteritidis PT 30 on almond surfaces. More than 4-log reduction was achieved at different treatment conditions for each of the control units. For instance, a 160 s treatment at 1500 W (100 Hz system) resulted in a 4.3 log CFU/almond reduction. Whereas, similar reductions were achieved in a shorter time with the lower frequency systems (1.8 or 3 Hz). Reductions of 4.6 and 5.9 log CFU/almond were achieved after 80 and 100 s treatment, respectively with the 1.8 Hz system (1250 W). Similarly, a 100 s treatment with the 3 Hz system (1000 W) resulted in a reduction of 4.7 log CFU/almond. Statistical analysis showed that the effect of equipment, treatment time, and electrical power input were significant (p<0.05). The D-values of 1.8, 3, and 100 Hz systems were 0.24, 0.53 and 0.73 min, respectively at 1500 W. In general, lower frequencies resulted in increased inactivation in shorter time. This can be attributed to the higher instantaneous power at lower frequencies. Similar trends were observed at other electrical input powers. The D-values found using pulsed light treatment are lower than the conventional dry heat treatment ones. Also, minimal color change was observed for treated almonds. These results indicate that pulsed light is efficacious for decontaminating almond surfaces within a relatively short time.
M.S. in Food Process Engineering, May 2016
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Title: Grinnell variable pressure alarm valve
Creator: Eyers, Walter, Thomson, F. L.
Date: 2009, 1908
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/grinnellvariable00eyer
Thesis (B.S.)--Armour Institute of Technology, 1908 B.S. in Fire Protection Engineering,...
Show morehttp://www.archive.org/details/grinnellvariable00eyer
Thesis (B.S.)--Armour Institute of Technology, 1908 B.S. in Fire Protection Engineering, 1908
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Title: NONLINEAR SIMULATIONS OF MULTI-VESICLE DYNAMICS
Creator: Hamiilton, Caleb
Date: 2015, 2015-07
Description: Vesicles in biology are closed forms of membranes. The dimensions of vesicles can vary in terms of surface area and enclosed volume. Examples...
Show moreVesicles in biology are closed forms of membranes. The dimensions of vesicles can vary in terms of surface area and enclosed volume. Examples range from small organelles to large cell bodies which all play a variety of resource transportation roles in biological systems. Research from the fields of chemistry and physics helps mathematical modeling by providing the mechanisms behind certain observed morphologies. Mathematical models and methods for simulating vesicle dynamics have produced accurate numerical solutions to verify experimental data and can be used to design new experiments that lead to more discoveries. The most researched case has been a single vesicle under shear flow. However, recent numerical and experimental results consider extensional flows on a single vesicle and hydrodynamic interactions among multiple vesicles. This thesis extends work on hydrodynamic interactions between vesicles in viscous fluid. We investigate numerically cases with multiple vesicles relaxing in asymmetrical configurations, time-dependent flow with more oscillation, and stochastic dynamics. Subjecting vesicles to these various cases reveals sensitivity to initial conditions such as distance and relative orientation. The effects from adding more vesicles are: increased time before equilibrium for the relaxation tests, and distributive wrinkling dynamics for the extensional flow tests. In stochastic cases, there are similar wrinkling distributions. However, initial conditions like distance and orientation have less important effects when competing with influence from thermal fluctuations. Additionally, in the presence of other vesicles under extensional flow, a vesicle may change the number and amplitude of wrinkles it would have experienced alone.
M.S. in Applied Mathematics, July 2015
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Title: Highway improvement in the state of Illinois
Creator: Sears, I. Lee
Date: 2009, 1915
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/highwayimproveme00sear
Thesis (B.S.)--Armour Institute of Technology; Includes "Contract form and general...
Show morehttp://www.archive.org/details/highwayimproveme00sear
Thesis (B.S.)--Armour Institute of Technology; Includes "Contract form and general specifications for bridge work"
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Title: POLARIZATION COUPLING IN SEMICONDUCTOR NANO-DIMERS IN THE TERAHERTZ RANGE
Creator: Hu, Zhijing
Date: 2017, 2017-05
Description: Surface plasmon resonance (SPR) occurs at the interface of a semiconductor and a dielectric when certain conditions are satisfied. SPR is...
Show moreSurface plasmon resonance (SPR) occurs at the interface of a semiconductor and a dielectric when certain conditions are satisfied. SPR is impetus to new sensor and device development in the optical range, with nanoparticles of noble metals taking up major roles. Typical conduction band electron concentrations in semiconductors lead to resonance frequencies in the terahertz and infrared bands. While the response strength is weaker than those exhibited by metals, it can be made up for by the formation of aggregates. The added degree of freedom by doping or carrier injection further enhances the versatility of semiconductor nanoclusters. To obtain a first principle solution to the coupled set of equations for charge carrier transport and electrodynamics in a conductive cluster is a formidable task with a high computational cost. Employing a finite-element based tool, the COMSOL Multiphysics Simulation Software, the interaction inside and outside some elementary semiconductor structures such as slab and sphere have been solved, which revealed the screening of the internal field while displaying dispersion and absorptions effects. The study of semiconductor dimer also showed a significant field enhancement and frequency shift. Under strong applied field, asymmetric polarization within the particles is revealed. The accompanying nonlinear polarization response can be employed to develop new devices. These model structures can serve to provide insight to the analysis and synthesis more complex structures.
Ph.D. in Electrical Engineering, May 2017
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Title: SALMONELLA SURVIVAL DURING INOCULATION AND STORAGE OF DRIED SPICES CONTAINING ANTIMICROBIAL COMPONENTS
Creator: Hu, Chuxuan
Date: 2016, 2016-05
Description: To provide an adequate initial microbial level for spices containing antimicrobial compounds for use in stability testing of foodborne...
Show moreTo provide an adequate initial microbial level for spices containing antimicrobial compounds for use in stability testing of foodborne pathogens, a dry-transfer inoculation was designed and compared with a traditional aqueous inoculation protocol. A five serovar cocktail of Salmonella spp. was prepared at different concentrations (~11 log CFU/mL, ~8 log CFU/mL and ~4 log CFU/mL). It was inoculated onto 1g silica beads and four types of dried ground spices (clove, oregano, ginger, and black pepper). Both spices and beads were dried for 24h at ambient conditions (~22°C). Silica beads were then used as a carrier to inoculate the same four types of spices. The results suggest that dry-transfer of Salmonella via inoculated silica beads provided a greater starting inoculum than aqueous transfer alone and are a viable alternative to aqueous inoculation when spices contain antimicrobial components. This dry-transfer inoculated ground clove with 8.4 log CFU/g and 3.9 log CFU/g initial populations was then used to determine the survival of Salmonella on spices containing antimicrobial components. Salmonella spp. survival on silica beads with 9.2 log CFU/g and 5.9 log CFU/g initial populations and subsequent transfer to ground clove was also examined. Samples were enumerated at selected time point up to 210 d. Results of this study indicate that Salmonella transfer and recovery from beads and in ground clove was not affect by storage and that Salmonella may persist for an extended period of time. The calculation of recovery was, however, affected by detection limits in clove. To improve detection limits an oil extraction was used and compared to the BAM method (detection limit 3.7 log CFU/g). After oil extraction the clove samples were soaked for 1 h (or 24 h for low inoculum concentration) in TSB at 37ᵒC and subsequently enumerated on tryptic soy agar with 0.6% yeast extract and xylose lysine deoxycholate agars. The result demonstrates that the oil extraction detection method holds promise as an alternative method to detect Salmonella in dry spices containing antimicrobial components and can provide a lower detection limit (1.7 log CFU/g).
M.S. in Food Process Engineering, May 2016
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Title: Humidifying air in living rooms by attachments to the steam radiator
Creator: Andre, G. L.
Date: 2009, 1918
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/humidifyingairin00andr
Thesis (B.S.)--Armour Institute of Technology; Biblography: leaf 60

Title: DESIGN OF INDUCTORLESS LOW NOISE AMPLIFIER
Creator: Huo, Yunsheng
Date: 2017, 2017-05
Description: With the rapidly increasing number of elements integrated on a single chip. The area on a chip became much costlier. And the difficulty of...
Show moreWith the rapidly increasing number of elements integrated on a single chip. The area on a chip became much costlier. And the difficulty of planning all the elements has been growing. So, decreasing the area cost of each single element became important to be considered. In the conventional technology, to cancel the imaginary part of the input impedance, inductors were used in the design of a LNA. However, inductor is an area consuming element, it would cost most of the chip area. To reduce the area cost of LNA, it is important to reduce the number of inductor, the best case is to design a LNA without any inductor. What’s more, without inductor, LNA would be able to work in a wideband frequency, but not a specific narrow-band frequency. But considering the imaginary part of input impedance, the highest frequency would reduce, depending on the f T of the MOSFET used in the design. In this thesis, the design considerations of heterodyne transceiver, which is the most popular architecture in modern RF design, are introduced firstly. Then, to reduce the undesired effect from image signal, a special architecture, called image-ejection architecture, is explained. To implement the proposal function, different architectures are shown. In RF receiver design, Low Noise Amplifier is one of the most important stages in the RX chain. To design a LNA which can meet different requirements of the RX design. Different topologies are explained, including CS stage, CG stage and differential LNA. Besides conventional technique, some up-to-date techniques are also shown, such as modified CG stage. The main propose of this thesis is to design an inductorless LNA. In this LNA design, Noise Canceling technology and Amplifier Enhancement technology were utilized to improve the noise and amplifying performance. After explaining the technologies theoretically, the circuit is simulated in a 65nm technology with working frequency band from 2 to 6 GHz. By the simulation, the gain of the design is beyond 14dB in the whole band, while the noise figure less than 2.8dB.
M.S. in Electrical Engineering, May 2017
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Title: A NANO-STRUCTURED CERAMIC/POLYMER COMPOSITE FILM FOR ELECTRONIC INTERCONNECTIONS
Creator: Harwath, Frank
Date: 2016, 2016-05
Description: Separable electrical interconnections are a ubiquitous part of modern life and for technical reasons are currently based on the use of gold....
Show moreSeparable electrical interconnections are a ubiquitous part of modern life and for technical reasons are currently based on the use of gold. Since gold is a commodity and subject to significant price fluctuations there is a need for separable interconnects not based on gold. Polymer/ceramic films were produced from various polymer precursors with loadings of multi-wall nanotubes (MWNT) and inert fillers. A variety of applications means were employed with the best success being achieved by means of a modified doctor blade. Pyrolysis was conducted in an inert atmosphere at 1 bar at a range of temperatures in a tube furnace. Pyrolysis was also conducted using a fiber laser. The modulus of the film is estimated to be 71.8 MPa with an ultimate tensile strength of 179 MPa based on hardness tests and anisotropic crack dimensions which developed as a result of uniaxial stress induced during application of the precursor. Uniaxial stress improved film adhesion regardless of filler type or level. Modification of film characteristics after pyrolysis was attempted using spark plasma sintering (SPS). Electrical testing displayed a percolation threshold above loadings of 1% (wt) of MWNTs where there is a significant drop in electrical resistivity. Further reductions in contact resistance were demonstrated up to 2% loading of MWNTs. The level of contact resistance achieved (<10) for a separable contact, in conjunction with a gold plated contact representative of most electronic connectors, indicates that an acceptable level of contact resistance may be achieved using these materials. Characterization of the film using attenuated total reflectance (ATR), xray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), and Raman spectroscopy point to a morphology which is dominated by crystallites joined by regions of aliphatic carbon chains. Work function measurements were consistent with highly ordered pyrolytic graphite. (HOPG)
Ph.D. in Materials Science and Engineering, May 2016
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Title: COMMUNITY ENGAGEMENT AND COMMUNITY RESPONSE OF FIRST TIME CODE CONTRIBUTORS ON GITHUB
Creator: Heston, Matthew
Date: 2014, 2014-05
Description: We collect data for 13,383 rst time code contributions from 45 projects on the website GitHub and analyze behavior of developers before...
Show moreWe collect data for 13,383 rst time code contributions from 45 projects on the website GitHub and analyze behavior of developers before submitting code as well as community response to code contributions. Our ndings di er from previous research on open source software communities and social theories of learning in communities of practice. We nd most users do not participate in GitHub peripheral activities before submitting code changes. We also nd that community response to these submitted code changes is a poor predictor of whether or not the code is accepted.
M.S. in Information Architecture, May 2014
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Title: CRITICISM, HEALTH FUNCTIONING, AND MARITAL ADJUSTMENT IN COUPLES WITH CARDIOVASCULAR DISEASE
Creator: Hicks, R. Elliott Iii
Date: 2017, 2017-07
Description: Destructive communication and hostile interactions between spouses are associated with poor behavior maintenance and can elicit substantial...
Show moreDestructive communication and hostile interactions between spouses are associated with poor behavior maintenance and can elicit substantial increases in systolic blood pressure, heart rate, and cardiac output in patients (Broadwell, & Light, 2005; Nealey-Moore et al., 2007; Ryan & Deci, 2000). This negatively impacts the cardiovascular health of the targeted partner (Nealey-Moore et al., 2007; Ryan & Deci, 2000; Smith et al., 2009). Constructive, non-hostile criticism between partners may bolster behavior change and maintenance (Zinbarg, 2007). The present study assesses the relationship between forms of criticism and reports of marital adjustment, autonomous support, health functioning, and health behavior change in a sample of couples participating in a cardiac risk reduction intervention. Results indicate that Hostile Criticism predicted Physical Health Functioning. Further, there were no significant moderating relationships. Interpretation of results and future directions are discussed.
Ph.D. in Psychology, July 2017
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Title: FROM EXPLORATION TO RATIONAL DESIGN OF SELECTIVE PROPANE DEHYDROGENATION CATALYSTS
Creator: Hu, Bo
Date: 2015, 2015-12
Description: Light olefins, e.g., ethene and propene, are important building blocks of chemical industry for the production of fuels, polymers, lubricants...
Show moreLight olefins, e.g., ethene and propene, are important building blocks of chemical industry for the production of fuels, polymers, lubricants and other fine chemicals. Due to the rapidly increasing production of shale gas, conversion of small alkanes in the shale gas, e.g., ethane and propane, to their corresponding olefins via alkane dehydrogenation could be an important industrial process. This thesis has focused on exploring the novel single site heterogeneous catalysts for selective alkane dehydrogenation and investigating the general principles of rational catalyst design to achieve a better performing (e.g., more active, more stable, highly selective) dehydrogenation catalyst. Based on the observed reactivity of ZnO for olefin hydrogenation and activity of Zn-ZSM-5 catalysts for alkane activation, catalytic properties of isolated Zn2+ were first explored for propane dehydrogenation. The 3-coordinate Zn in single site Zn/SiO2 catalyst was demonstrated to be the catalytically active species that was highly selective for the generation of propene by propane dehydrogenation. DFT calculations revealed that slow β-hydride elimination of alkyl intermediates limited the overall activity of single site Zn/SiO2 catalyst. Thus, single site Co/SiO2 was also prepared in order to take the advantage of fast β-hydride elimination. The higher activity of single site Co/SiO2 emphasized the potential of transition metals for alkane dehydrogenation, and propane dehydrogenation reactivity of transition metals was further explored by investigating single site Fe/SiO2 catalyst. By comparing with metallic Fe nanoparticles and bulk phase Fe oxides catalysts, the 3-coordinate single site Fe2+ was also suggested to be the catalytically active species for selective propane dehydrogenation. However, the catalytic activity of single site Fe/SiO2 catalyst was lower than that of Zn/SiO2. Such result suggested heterolytic cleavage of C-H bonds was slow for transition metals, e.g., Co and Fe, due to their weak Lewis acidity, and it may mitigate the advantages gained in rapid β-hydride elimination. An exploration of ligand effects for improving heterolytic cleavage over single site heterogeneous catalysts was performed. The strength of metal oxygen bond governed by ligand electron donating effects and ligand basicity were found to be the critical chemical descriptors for a facile heterolytic cleavage. Those observed principles of ligand effects would lead to a new strategy of rational catalyst design for a superior dehydrogenation catalyst.
Ph.D. in Chemistry, December 2015
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Title: High speed tool steel on lathe work
Creator: Hayes, C. E., Wilson, F. N.
Date: 2009, 1906
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/highspeedtoolste00haye
Thesis (B.S.)--Armour Institute of Technology

Title: A KINETIC MODEL TO ESTIMATE VASCULAR PERMEABILITY FROM FLUORESCEIN VIDEOANGIOGRAPHY DATA
Creator: Hu, Shaoxian
Date: 2017, 2017-05
Description: Diabetic retinopathy (DR) is a disease affecting the tissue of the retina through hemodynamics and vascular damage that is a side effect of...
Show moreDiabetic retinopathy (DR) is a disease affecting the tissue of the retina through hemodynamics and vascular damage that is a side effect of hyperglycemia. As such, markers of hemodynamic and vascular irregularity have been proposed as potential early indicators of the disease. However, conventional approaches to estimate these conditions are not sensitive enough, leading to indications that are too late, appearing only after irreversible vision problems have occurred. Indicator-dye-dilution tracer kinetic modeling is a decades-old methodology that can be used to quantify blood flow and vascular permeability based on the kinetics of a rapidly injected blood pool imaging agent. The methodology is able to track sensitive hemodynamic changes in stroke and heart disease patients, yet it has never been applied to blood flow and vascular permeability mapping of the retina. The purpose of my Master’s thesis was to adapt those tracer kinetic methods to fluorescein retinal videoangiography data collected in human to map both blood flow and vascular permeability so that in future work, changes in these parameters can be quantified at varying stages of the development of DR. Studies were carried out on simulated data, healthy and diabetic rats, and healthy and diabetic humans. While a robust validation of measures of blood flow and vascular permeability are still required, this first-of-its-kind study exposed many unique complications in applying the kinetic models to human fluorescein videoangiography data. Specifically, eye motion must be accounted for, both detector and fluorescein fluorescence quenching signal saturation must be avoided, and standard use of automatic gain control of imaging exposure should not be used (though corrections were developed for this); rather, data should be collected at a stable exposure throughout a measurement. Solutions were developed for all of these complications that were tested in rat models (optimal data collection in humans is ongoing). In rat study, average vascular permeability in the rat measured by the “extraction fraction”, the extraction fraction in control subject (n=3) 9.4e-4±1.3e-3, is lower than STZ-diabetic subjects (n=3) 5.5-2±5.17e-2 and VEGF group (n=3) 7.6e-2±5.1e-2. In healthy human volunteers, retinal extraction fraction was measured to be 5.0e-5 ± 6.1e-5 (n=2), whereas this was found to be elevated to 1.2e-3 ± 1.0e-3 in patients for diagnosed DR (n=3). These early results clearly demonstrated a statistically significant elevation in vascular permeability in all diabetic groups compared to controls (p<0.05). The human study was carried out on advanced cases of patients who were known to have DR as a test case; however, the sensitivity of the approaches is demonstrated by the eatly changes in extraction fraction observed at only 48 h after the onset of hyperglycemia in the rat experiments (well before irreversible damage to the retina had occurred). These results are promising for the adaptation of our modified kinetic modeling approach to measure hemodynamics and vascular permeability changes during the early onset of DR when preventative therapies could be most effective.
M.S. in Biomedical Engineering, May 2017
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