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- Title
- THREE ESSAYS ON CORPORATE FINANCE
- Creator
- Wang, Jianrong
- Date
- 2020
- Description
-
This dissertation is comprised of three distinct but related essays in corporate finance. In the first essay, I examine how the CEOs paid with...
Show moreThis dissertation is comprised of three distinct but related essays in corporate finance. In the first essay, I examine how the CEOs paid with inside debt utilize corporate social responsibility activities to reduce firm risk taking. In the second and third essays, I explore the possible determinants of private placement. The first essay focuses on managerial incentive induced by debt-like compensation such as deferred compensation and defined benefit pensions. Building on cumulative prospect theory and instrumental stakeholder theory, I hypothesize that CEOs paid with debt in their own firms have risk-reduction incentives, and corporate social responsibility (CSR) activities mediate the relationship between debt-like compensation and firm risk taking. Furthermore, I argue that the mediated relationship between CEO debt-like compensation and firm risk taking is context dependent, and I propose that two contingencies, namely environmental dynamism and munificence, moderate the mediated process. My analyses, based on a large longitudinal dataset of nonfinancial US firms, lend strong support for these hypotheses. The second essay examines the impact of firm’s social capital on the cost of Rule 144A debt. I find that Rule 144A debt issuing firms headquartered in the high social capital county pay lower yield spread their peers. Furthermore, the finding suggests that the effect of social capital becomes weak when the issuers have more firm-specific public information and credit records. The relation between social capital and the cost of debt is contingent on industry environment. The results reveal that firms located in high social capital counties have low bankruptcy likelihood and low risk level after Rule 144A debt issuance. The third essay focuses on the role of prior technology alliances in the PIPE issuance. Relying on the data collected from Placement Tracker and SDC platinum, I empirically investigate the relationship between issuers’ technology alliance experiences and their PIPE offering contracts. I document that the greater alliance experiences at the time of the PIPE issuance, the smaller PIPE price discount and fewer contract terms that are favorable to investors. The results indicate that the technology alliance experience alleviates the information asymmetry between issuers and investors and improve issuers’ bargaining power. I further find that issuers with more alliance activities exhibit a more positive announcement effect and outperform in the long run. Moreover, the effect of technology alliance experience is stronger if the issuers partner with large firms, whereas the effect is weaker if the issuers are in high-tech industries.
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- Title
- AGENT-BASED MODELING OF IMMUNE RESPONSE IN THE DEVELOPMENT OF TYPE 1 DIABETES
- Creator
- Xu, Qian
- Date
- 2020
- Description
-
Diabetes is a chronic disease that affects a large number of people around the world and cause many co-morbidities ranging from cardiovascular...
Show moreDiabetes is a chronic disease that affects a large number of people around the world and cause many co-morbidities ranging from cardiovascular diseases, neuropathy, retinopathy and blindness and kidney failure. The economic burden induced by diabetes is not only caused by the wage loss and medical burden, but also with the cost of treatment of diabetes and co-morbidities caused by diabetes. Clinical research for treatment and cure of diabetes is costly. Computer modeling and simulation studies provide an economical alternative to conduct preliminary evaluation of new hypotheses and alternatives in new therapies. The most promising results obtained from simulations can then be investigates experimentally, improving the efficiency of experiments and clinical studies. This work focuses on the development of an agent-based model to describe the destruction of islets and β cells and the development of Type 1 diabetes. The whole process of inflammation related to diabetes takes place in pancreatic lymph node, circulation, and pancreatic tissue with islets. The infiltration to islets and insulin-producing β cell damage happens in the pancreatic tissue with islets; the lymphocytes activation and antigen presentation majorly happened in the pancreatic lymph node. Therefore, the model described activities taking place in the islets in the pancreatic tissue section and pancreatic lymph nodes, the interactions among T cells, α/β cells, antigen presentation cells and immunosuppression cells. Cell behavior was obtained from the literature that published experiment results and used to develop the rules followed by the agents representing various types of cells and their interactions. The agent-based model provides a framework to describe relationship between lymphocytes and β cell through the trends of cell variations in the inflammation and demonstrates the effects of these cells in the disease development. Two different systems, a mouse model and a human model have been developed. The simulation results with the mouse model indicate that the different types of regulatory cells play different roles in suppressing inflammation. Among them, the regulatory T cells play the most important role in suppressing inflammation, but the B regulatory cell conversion is the key to induce the cascade of regulatory cell generation in inflammatory environment when there are no regulatory cytokines in the environment. The simulation results with the human model are mostly similar with mouse model, however, their effect of potential therapies such as addition of Tregs did not do as well as that in mouse model. The treatment method might be adjusted by combining other cytokines or immunosuppression cells in human assays.
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- Title
- Developing Leader Identity via Structured Reflection
- Creator
- Standish, Melanie P.
- Date
- 2020
- Description
-
As leader identity research in the context of leader development continues to expand, it is important to understand the mechanisms through...
Show moreAs leader identity research in the context of leader development continues to expand, it is important to understand the mechanisms through which leader identity becomes more central to one’s self concept. Structured leadership reflection is proposed to positively impact leader development but has not been experimentally manipulated to understand what its impact is on leader identity change. In this study, 90 participants were assigned into one of three reflection conditions and were asked to respond to reflection prompts over the course of four days. Participants were divided into the control condition, the reflecting on others as leaders condition, or the reflecting on oneself as a leader condition. Results showed no significant differences between reflection groups and their impact on leader identity change. Though our results do not provide support for the use of structured reflection to elicit leader identity development, we suggest future research should further study structured self-reflection over a longer period of time.
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- Title
- GROWTH KINETICS OF LISTERIA MONOCYTOGENES DURING REHYDRATION OF DEHYDRATED PLANT FOODS AND SUBSEQUENT STORAGE
- Creator
- Wu, Zihui
- Date
- 2020
- Description
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Dehydrated plant foods do not support the growth of pathogenic bacteria. However, once rehydrated, the high-water activity and neutral pH of...
Show moreDehydrated plant foods do not support the growth of pathogenic bacteria. However, once rehydrated, the high-water activity and neutral pH of these foods may support the growth of pathogens, such as L. monocytogenes, during storage. The goal of this study was to examine the growth kinetics of L. monocytogenes during 5, 10, and 25°C storage on potatoes, carrots, and onions after rehydration with 5 or 25°C water. Fresh plant foods were dehydrated at 140°F (60°C) for 24 h. A 4-strain rifampicin-resistant L. monocytogenes cocktail was inoculated onto dehydrated plant foods at 4 log CFU/g and dried for 24 h. Plant foods were rehydrated in 4-volumes of 5 or 25°C water for 24 h. At various timepoints during rehydration, 30 g of sample was removed and drained for 10 min. Samples were homogenized 1:10 with BLEB and the homogenate was plated onto BHIRif for enumeration. After rehydration, samples were drained and portioned into deli-style containers for storage at 5, 10, and 25°C and L. monocytogenes was enumerated at 1, 3, 5, and 7 d. Triplicate samples were assessed at each timepoint and three independent trials were conducted. Growth rates were determined using DMFit and data were statistically analyzed using Student t-test (α=0.05). Overall, the growth rates of L. monocytogenes during storage of potatoes and carrots were higher when rehydrated with 5°C water compared to 25°C water. The highest growth rate on potatoes was 3.51±0.43 log CUF/g per d with 5°C water rehydration and 25°C storage, resulting in a 1 log CFU/g increase in 0.29 d (7.0 h). When rehydrated with 25°C water and 25°C storage, the growth rate was significantly lower at 1.03±0.01 log CFU/g per d. The highest growth rate of L. monocytogenes on carrots was 0.68±0.07 log CUF/g per day when rehydrated with 5°C water and 10°C storage, resulting in a 1 log CFU/g increase in 1.47 d (35.3 h). For onion, L. monocytogenes was below the level of enumeration during storage at 5°C for both water rehydration temperatures and also for 10°C storage with 5°C water rehydration. The highest growth rate was 0.46±0.11 log CFU/g per d, resulting in a 1 log CFU/g increase in 2.17 d. The results of this study can aid in determining appropriate time and temperature control for safety for dehydrated potatoes, carrots and onions during rehydration and subsequent storage.
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- Title
- Analyzing Online Reviews in E-Retailer Platforms: A Structural Equation Modeling Approach
- Creator
- Zhou, Zheng
- Date
- 2020
- Description
-
In recent years, the role of online shoppers has transformed from a passive information receiver into an active shopping experience sharer,...
Show moreIn recent years, the role of online shoppers has transformed from a passive information receiver into an active shopping experience sharer, which makes reading the reviews left by peer shoppers a very important factor in consumer purchase decisions. However, fake online reviews are flooding websites and consumers are gradually becoming aware of that. This encourages consumers’ skepticism toward the credibility of online reviews. Using a structural equation modeling approach, this study analyzes the effect of consumers’ perceptions of shopping platform characteristics and online review trustworthiness on their purchase intention. Conditional process analysis was used to study the moderation effect of consumers’ skepticism during their shopping experience. A total of 1,004 valid responses were collected through an online survey administered by Qualtrics.Results indicate that consumers’ perceived platform trustworthiness contributes to the trustworthiness of its online reviews, which in turn both directly and indirectly increases purchase intention. Most parts of the proposed conceptual model are supported by empirical results with a few exceptions: consumer’s perceived review quantity is found to have a positive impact on perceived review quality and platform quality is found to be directly related to consumers' perceived risk. All re-specifications increase the model fit, followed by cross-validation that yields satisfactory model stability. With the establishment of measurement invariance, we discuss structural invariance across sub-groups and present some interesting findings. Results also show that all three dimensions of consumers’ skepticism negatively moderate the direct effect of the review’s trustworthiness on purchase intention. However, unlike the other two items (skepticism toward review trustworthiness and reviewer's motivation), consumers’ skepticism toward the reviewer's identity does not moderate the indirect causal path between review trustworthiness and purchase intention through perceived risk. We also adopt a different approach using latent moderated structural equations to support our findings. From a research perspective, this study contributes to our understanding of how consumers absorb information from online reviews to develop appropriate responses (e.g., purchase intention). From a practice perspective, this study provides insights on how platform and seller should respond to and properly manage consumers’ perceptions and skepticism toward online reviews.
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- Title
- RECIPROCAL INTERACTIONS BETWEEN RED RASPBERRY POLYPHENOLS AND GUT MICROBIOME COMPOSITION AND METABOLIC HEALTH
- Creator
- Zhang, Xuhuiqun
- Date
- 2020
- Description
-
Red raspberries (RRB) and fructo-oligosaccharides (FOS) have been associated with reduced risk of developing cardio-metabolic diseases. RRB...
Show moreRed raspberries (RRB) and fructo-oligosaccharides (FOS) have been associated with reduced risk of developing cardio-metabolic diseases. RRB are uniquely high in anthocyanin- and ellagitannin- type (poly)phenols, however, these (poly)phenols have low bioavailability. Gut microbiota can improve (poly)phenol bioavailability through fermentation processes generating absorbable metabolites and altering gut microbiota structure. However, clinical evidence on the effects of RRB intake on the gut microbiome, (poly)phenolic metabolites and metabolic health is lacking. Further, fermentable carbohydrates (FOS) that selectively stimulate gut microbiota growth may enhance metabolite generation. Therefore, the aim of this research is to investigate the interactions between the gut microbiome and RRB, and explore added effects of FOS as a possible nutritional strategy for improving metabolic health of at risk individuals with prediabetes and insulin resistance (PreDM-IR). Through a series of investigations drawn from a randomized clinical trial (RCT), the following hypotheses were tested: 1) Individuals with PreDM-IR will have a distinctive gut microbiome, and lower capacity to metabolize (poly)phenols compared to healthy individuals; 2) RRB intake for 4-week will increase microbial-derived (poly)phenolic metabolites and adding FOS will augment the effect; 3) RRB intake will improve metabolic risk factors in PreDM-IR and adding FOS will augment the RRB effect; 4) RRB and RRB+FOS supplementations will alter the structure of the gut microbiome explaining variances observed in metabolites and metabolic outcomes. In this single-blinded, crossover RCT, adults with PreDM-IR (n=26) and a healthy group (n=10) consumed 1 cup RRB (fresh weight equivalence) per day or RRB with 8g FOS per day for 4 weeks in random order separated by 4-week washout. Metabolic risk factors, (poly)phenolic metabolites and metagenomic profile were assessed before and after supplementation. Baseline characterization before supplementation revealed distinctive metabolites and metagenomics profiles related to metabolic status. After 4-week RRB, microbial (poly)phenolic metabolites, metabolic health indices and gut microbiome structure beneficially shifted in PreDM-IR group. Adding FOS increased specific microbial species and phenolic metabolites that correlated with β-cell function in PreDM-IR. Overall, nutritional strategies incorporating RRB and FOS may improve metabolic health of individuals with PreDM-IR through modulating gut microbiome composition and the capacity to metabolize RRB (poly)phenols.
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- Title
- Application-Oriented Scheduling for Optimizing Information Freshness in Wireless Networks
- Creator
- Yin, Bo
- Date
- 2020
- Description
-
Recent years have witnessed a significant advancement of networking technologies as well as the proliferation of mobile devices. Due to the...
Show moreRecent years have witnessed a significant advancement of networking technologies as well as the proliferation of mobile devices. Due to the convergence of pervasive connectivity and ubiquitous computing, Internet of Things (IoT) systems are becoming increasingly information-centric. For those IoT devices, wireless communication is the dominant way to exchange information. The development of IoT has spawned a plethora of real-time applications, boosting the demand for timely information updates. Age of Information (AoI) has recently been introduced to quantify the freshness of the knowledge the controller has about the remote information sources. Due to its sheer novelty in capturing the timeliness requirements of various applications, AoI has sparked tremendous interest and been studied in many communication systems. This thesis aims at an exploratory study on how to characterize the essence of wireless scheduling for effective information freshness from the decision-making perspectives through two representative application scenarios, information retrieval and information integration. For the former, request-aware proactive scheduling policies in both static and dynamic request patterns are developed, which target at minimizing time-average effective AoI (EAoI). For the latter, an experience-driven scheduling framework based on deep reinforcement learning techniques is investigated to minimize the time-average AoI in the presence of correlated information sources. Future research directions are also discussed to present possible extensions of this thesis work to a broader range of network scenarios.
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- Title
- FINANCIAL BURDEN AND COPING IN HEAD AND NECK CANCER PATIENTS
- Creator
- Yap, Bonnie Joyce
- Date
- 2020
- Description
-
In order to contribute to knowledge about how treatment impacts the financial well-being of patients diagnosed with head and neck cancer, this...
Show moreIn order to contribute to knowledge about how treatment impacts the financial well-being of patients diagnosed with head and neck cancer, this study examined the relationship between patient characteristics, financial burden, and financial coping over the treatment period among patients receiving treatment for locally advanced head and neck cancer at a major midwestern medical center. A sample of 65 participants completed self-report questionnaires on out-of-pocket costs, use of financial coping strategies, healthcare utilization, and personal and medical characteristics. Participant disease-specific information was obtained from their medical charts. Age, illness intrusiveness, and distance significantly predicted use of lifestyle-altering financial coping strategies. In addition, human papillomavirus (HPV) status significantly predicted use of care-altering financial coping strategies. Results of hierarchical linear regression analyses found significant main effects of financial burden, loneliness, and social support as predictors of the use of financial coping strategies. Moderation effects of loneliness and social support were not found. Trajectories of out-of-pocket costs indicated that costs are highest at the beginning of treatment and decrease over time. The results highlight the non-disease characteristics of patients diagnosed with head and neck cancer that may make them more vulnerable to financial distress and financial burden. Future studies with larger and more representative sample sizes could further add to information about the impact of cancer treatment on patient financial wellbeing.
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- Title
- Parameterization of vertical dispersion coefficient (σz) near roadway: vehicle wake, density and types
- Creator
- Yu, Yu-Ting
- Date
- 2020
- Description
-
Pollutants emitted by motor vehicles is one of the major public concern in modern society since pollutants (e.g. ultrafine particles and CO2)...
Show morePollutants emitted by motor vehicles is one of the major public concern in modern society since pollutants (e.g. ultrafine particles and CO2) have been related to adverse health effect and climate change. Currently, air quality dispersion models (e.g. CALINE4 and AERMOD) are widely used to predict concentration near roadway. However, both air quality dispersion models are not account for the vehicle variability (vehicle types), causing the inaccuracy in predicting pollutant concentration near roadway. To better understand the dynamic of dispersive process, it is important to evaluate the variation of vertical dispersion coefficient (σz) for different vehicle types (e.g. LDV and HDV). A “wake area model” is developed based on “effective wake area” and vehicle density to reveal the dynamic of dispersion process that related to vehicles. Results from this thesis demonstrate that the near roadway σz that calculated from field measurements increases as vehicle density increases and HDV can generate higher value of σz compare to LDV. σz increase from 1.7 m to 4 m with LDV density increase from 0.005 m-1 to 0.18 m-1; while σz starts at 2 m and reach up to 6 m with HDV density increase from 0.001 m-1 to 0.01 m-1. The significant differences of σz are due to vehicle density and vehicle types. The effective wake area contributed by one HDV (397 m2) is much larger than effective wake area contributed by one LDV (13 m2), which indicates that one HDV contributes 31 times higher than one LDV in terms of near roadway σz. The significant differences of “effective wake area” are due to vehicle wake structure and vehicle dimension.Compared to the air quality dispersion models results, both CALINE4 and AERMOD failed to respond the variation of σz as vehicle density increases for LDVs and HDVs. CALINE4 shows the value of σz is near 2.8 m and 2.4 m for LDV and for vehicle fleet (mixture of LDV and HDV), respectively. AERMOD shows the value of σz is near 1.2 m and 1.3 m for LDV and for vehicle fleet, respectively. Because both air quality dispersion models did not correctly predict σz near roadway, a new equation that parameterize σz near roadway need to be developed to better predict the σz in real world condition. For a given road segment, the parameterization of σz is a result from dimension of “effective wake area” for different vehicle types and number of “effective wake area” for a vehicle fleet. Comparison of measured and parameterized σz near roadway dispersion coefficients show good agreement (slope=0.99, R2=0.85) with a range between 1 and 4 m for LDVs and 2 to 6 m for HDVs. Also, Comparison of measured and simulated CO2 show good agreement (slope=1, R2=0.90) with a range between 0.01 g m-3 to 0.12 g m-3 for simulated value and 0.01 g m-3 to 0.14 g m-3 for measured value. For UFPs, the results also show good agreement (slope=1.14, R2=0.71) with a range between 600 pt cm-3 to 11,000 pt cm-3 for simulated value and 600 pt cm-3 to 17,000 pt cm-3 for measured value.The “wake area model” provides a new perspective for σz that related to vehicles and bridges vehicle wake to σz. The results from this study will be critical for improving predictions of pollutant concentration from air quality dispersion near roadway.
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- Title
- Technology News, April 09, 1946
- Creator
- Illinois Institute of Technology
- Date
- 1946-04-09, 1946-04-09
- Collection
- Technology News Microfilm collection, 1928-1981
- Title
- Armour Institute of Technology campus, Chicago, Illinois, ca. 1901
- Date
- 1901
- Description
-
Photograph of the Armour Institute of Technology campus, including the Armour Mission, Main Building, and Machinery Hall, taken from Ogden...
Show morePhotograph of the Armour Institute of Technology campus, including the Armour Mission, Main Building, and Machinery Hall, taken from Ogden Field. Photographer unknown, possibly C.V. Smith. Date of photograph unknown. Date indicated is an estimate.
Show less - Collection
- C.V. Smith photographs, circa 1900-1929
- Title
- Technology News, September 23, 1946
- Creator
- Illinois Institute of Technology
- Date
- 1946-09-23, 1946-09-23
- Collection
- Technology News Microfilm collection, 1928-1981
- Title
- The effect of information overload on knowledge recall and related cognitions for an educational program based on the Mental Health First Aid Model
- Creator
- Bink, Andrea B.
- Date
- 2020
- Description
-
Early-intervention public health education programs have been effective at teaching a skillset to help others. However, some of these programs...
Show moreEarly-intervention public health education programs have been effective at teaching a skillset to help others. However, some of these programs have also been criticized for delivering more information than is necessary to learn the skill. Receiving too much information could cause information overload and interfere with program goals. The current study investigated the differential effect on outcomes of two trainings: (i) a standard training with lecture material about depression and anxiety (illness-information), and a skillset to guide interpersonal support for someone with depression and anxiety (skill-information); and (ii) a targeted training that omitted the lecture material and only presented the skillset. Predicted outcomes were that the combination of illness-information and skill-information in the standard training would result in information overload and would interfere with skill-information recall and attitude change. The current study also investigated two variables that could influence outcomes: general information overload about mental health (MHIO) and interest in the topic of mental health. Results were that participants in the standard training endorsed significantly more information overload and performed significantly better on recall measures than participants in the targeted training. Both trainings were effective at attitude change. Finally, preexisting MHIO was associated with training information overload, care seeking, and skill-information recall. Preexisting topic interest was associated with skill-information recall. Results suggest that some background lecture material might be necessary to learn how to support someone with depression and anxiety. Also, programs that promote interpersonal support are effective at attitude change no matter how much information they provide.
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- Title
- Small Molecule Ligands and Antibody Drug Conjugates for Potential Application in Targeted Cancer Therapy and PET Imaging
- Creator
- Ren, Siyuan
- Date
- 2020
- Description
-
Cancer has been a deadly disease threatening humans. Traditional treatment methods such as chemotherapy with non-specific targeting may cause...
Show moreCancer has been a deadly disease threatening humans. Traditional treatment methods such as chemotherapy with non-specific targeting may cause severe side effects to normal cells and tissues. Novel and better methods for treatment and imaging of cancer has been eagerly sought. We wanted to develop new small molecule inhibitors and antibody drug conjugates for targeted cancer therapy and imaging. Theranostic conjugates combining therapeutic entity and imaging agent are useful in treatment and diagnosis of cancer. We designed a theranostic conjugate containing iron chelating anti-tumor agent and optical imaging probe. Novel iron chelator CAB-NE3TA displayed significant anti-proliferation activity against several cancer cell lines and was conjugated to targeting antibody panitumumab (PAN). The therapeutic conjugate exhibited excellent anti-tumor efficacy and targeting ability to EGFR overexpressed on cancer cells such as skin cancer (A431). The theranostic conjugate CAB-NE3TA-PAN loaded with a near IR fluorescent dye provided promising anti-tumor efficacy and optical imaging in tumor-bearing mice. Tetrahydroisoquinoline (THIQ) analogues were synthesized and evaluated for cytotoxicity against different cancer cell lines. Our in vitro studies showed that the THIQ analogues exhibited anti-proliferative activities against multiple cancer cell lines. Cytotoxicity study revealed that anti-tumor activity of THIQ analogues are structure-dependent. Binding affinity between THIQ analogues and a potential target Tdp1 was determined. Positron emission tomography (PET) has been used in diagnosis of cancer. In this study, small molecules and chelators with potential donor groups were evaluated systematically for complexation with 89Zr for PET imaging. New ligands with different donors were evaluated for radiolabeling efficiency and complex stability with 89Zr. The theranostic conjugate (CAB-NE3TA-PAN-IR800) and small molecule THIQs and 89Zr-chelators showed encouraging results for potential applications in for therapy and imaging of cancer.
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- Title
- The Differential Influence of Computerized Neuropsychological Assessment Across Psychopathology
- Creator
- Singh, Shifali
- Date
- 2020
- Description
-
The method of administering neuropsychological assessments has transformed with the advent of novel technologies. The present study examined...
Show moreThe method of administering neuropsychological assessments has transformed with the advent of novel technologies. The present study examined how the manual versus computerized administration of the Wisconsin Card Sorting Test (WCST) influenced the relation between psychological symptom severity and performance on the WCST, using perseverative responses and failures to maintain set (FMS) subscales. The Dot Counting Test, Depression Anxiety Stress Scales, and SUPPS-P Impulsive Behavior Scale were used to measure performance validity, depression and anxiety, and impulsivity. Eighty-five participants were recruited from the Chicagoland area. Participants reported their age, gender, handedness, education, ethnicity, computer and smartphone familiarity, and medication use. Age ranged from 18 to 66 years (mean (SD) = 34.3 (15.8)), and 49.4% were recruited from an outpatient facility. For perseverative responses, both method of administration of the WCST were equivalent regardless of psychological symptom severity. For FMS, method of administration itself influenced performance, and particularly the impact of impulsivity symptom severity on FMS. Specifically, method of administration significantly moderated the relationship between FMS and Lack of Perseverance, Sensation Seeking, and Positive Urgency. There were also significant main effects between FMS, Lack of Perseverance, and Positive Urgency. The findings from this study suggest that the equivalence between the manual and computerized versions of the WCST depends on the WCST subscale and the type of psychological symptom. New normative data need to be developed for the computerized WCST, along with a more consistent method of scoring and interpreting WCST subscales.
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- Title
- The Association Between Executive Functioning, Verbal Memory, and Internalized Stigma in Predicting Psychotropic Medication Adherence Behaviors Among People with Serious Mental Illness
- Creator
- Powell, Karina
- Date
- 2020
- Description
-
Long-term symptom management is an important consideration for many individuals with serious mental illness to maintain recovery over time,...
Show moreLong-term symptom management is an important consideration for many individuals with serious mental illness to maintain recovery over time, prevent relapse and rehospitalization, and decrease symptom severity. Psychotropic medications can be an important aspect of treatment planning; however, many barriers exist that can impact medication adherence and treatment efficacy. Research suggests that internalized stigma and neurocognition may impact medication adherence, but research has yet to investigate the relationship between these three constructs in tandem. In this study, medication adherence was measured via medication possession ratio calculated from pharmacy records (objective) and self-reported medication use (subjective). Selection of neurocognitive domains and assessment measures was informed by MATRICS and ISBD-BANC consensus batteries. The primary expectations were that verbal memory and executive functioning would be related to medication adherence behaviors and that these domains would moderate the relationship between internalized stigma and medication adherence. A consistent association was seen between measures of self-reported medication use over time, suggesting participants were generally consistent in their reported use. While analyses testing the primary hypotheses were nonsignificant, in the context of limitations of statistical power, trends emerged that may be worthy of further investigation. Future research should continue to explore the potentially multifaceted relationships between factors contributing to adherence. A more comprehensive understanding these relationships has implications for clinicians and consumers in addressing treatment barriers and disengagement by developing more nuanced and targeted interventions.
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- Title
- A Novel Remote Sensing System Using Reflected GNSS Signals
- Creator
- Parvizi, Roohollah
- Date
- 2020
- Description
-
This dissertation presents a method to remotely sense freshwater surface ice and water using reflected signals from Global Navigation...
Show moreThis dissertation presents a method to remotely sense freshwater surface ice and water using reflected signals from Global Navigation Satellite Systems (GNSS). A portable ground-based sensor system is designed and built for collecting both scattered Global Positioning System (GPS) signals and independent validation data (lidar and camera) from the surface. GPS front-end signals are collected from both a direct receiving antenna facing upward and from a reflection-receiving antenna facing downward. Multiple data campaigns are conducted on the Lake Michigan waterfront in Chicago. A customized software receiver tests a new signal processing method to detect and acquire Global Navigation Satellite System (GNSS) signals reflected from the lake surface ice and collected by a downward-facing antenna. The method, modified differential coherent integration, multiplies time-shifted auto-correlation samples. The new method is evaluated against three conventional integration methods (coherent, incoherent, and differential integration) with signals from the direct antenna. With front-end samples from the reflection antenna, the new method is the only one of the four methods compared that acquires satellites in the reflected GPS signals, with three acquired using 10 ms of integration.The lidar surface scans are mapped with camera images and estimated reflection points to indicate the surface reflection type and to provide surface height relative to the sensors. For one satellite whose specular point is estimated to be on the ice surface, a Delay Doppler Map (DDM), signal-to-noise (SNR) ratio, and surface reflectivity (SR) are computed with the modified differential coherent integration method using the GPS. The DDM shows that, with modified differential integration, the satellite can be acquired in the reflected signal. For two satellites whose reflection points scan across ice and water over time the SNR and SR are computed over time. The SR is shown to be lower for liquid water than lake ice. This system concept may be used in the future for more complete mapping of phase changes in the cryosphere.
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- Title
- The Impact of Depression and Cognitive Dietary Restraint on the Association between Obstructive Sleep Apnea and Disordered Eating Behaviors
- Creator
- Schwartz, Natalie
- Date
- 2020
- Description
-
Obstructive sleep apnea (OSA) is characterized by loud snoring and repeated episodes of obstruction in the upper airway during sleep that...
Show moreObstructive sleep apnea (OSA) is characterized by loud snoring and repeated episodes of obstruction in the upper airway during sleep that cause partial or total stop in the airflow, often resulting in short, disruptive sleep. Sleep disruption as a result of OSA has been shown to result in reduced cognitive functioning and disordered eating behaviors, however, few studies to date have sought to determine whether OSA is associated with disordered eating behaviors. Bariatric patients are asked to restrict their food intake prior to surgery; however, restraint theory suggests that the eating behavior of those intending to restrict their intake can be disinhibited by a variety of conditions, which cause the restrained eater to engage in disinhibited and overeating behaviors. Depression has also demonstrated an association with disordered eating behaviors and cognitive dysfunction. Affect regulation theory is often cited as a possible explanation for this association, with the desire to avoid unpleasant affective states resulting in disordered eating behaviors. A sample of 93 bariatric surgery candidates were recruited from an academic medical center in a large metropolitan city to participate in the current study. Participants were recruited during their routine pre-surgical assessment for bariatric surgery and completed measures of disordered eating and depression. Both body mass index and diagnosis of OSA were obtained from patient medical chart. It was hypothesized that the presence of OSA would be related to higher levels of disordered eating behaviors, including disinhibited eating, frequency of loss of control and frequency of binge eating. Additionally, it was hypothesized that cognitive dietary restraint would moderate the association between OSA and disordered eating in bariatric patients, such that the greater the intent to strictly control food intake (i.e., greater cognitive dietary restraint), the more strongly sleep disturbance will be associated with disordered eating. Finally, it was hypothesized that depression would mediate the association between OSA and disordered eating in bariatric patients, such that depressive symptomatology accounts for the relation between OSA and disordered eating behaviors. Results indicated that the presence of OSA was not related to higher levels of disordered eating behaviors, nor did depression mediate the association between OSA and the disordered eating outcomes. Two of the moderation models were significant, including the disinhibited eating model and the frequency of loss of control over eating model. Although bariatric patients are encouraged to restrict their food intake, findings suggested that restraint does not appear to function as intended in reducing disinhibited eating behaviors in individuals with OSA. The findings for the loss of control model supported restraint theory and suggested that those with OSA who also endorse high restraint are at increased risk for experiencing loss of control over eating, whereas those who do not have cognitive dysfunction associated with OSA may or may not exhibit the same association. The current study highlights the impact of restraint on bariatric patients’ disordered eating behaviors, suggesting that restraint theory may not be entirely applicable to bariatric populations and may depend on the disordered eating behavior being examined. The current study also points to numerous gaps in the current literature and provides future directions for research on OSA and disordered eating in bariatric populations.
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- Title
- GAME THEORY BASED LOCATION-AWARE CHARGING SOLUTIONS FOR NETWORKED ELECTRIC VEHICLES
- Creator
- Laha, Aurobinda
- Date
- 2020
- Description
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The recent explosive adoption of electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs) has sparked considerable interest of...
Show moreThe recent explosive adoption of electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs) has sparked considerable interest of academia in developing efficient charging schemes. Supported by the advanced vehicle-to-grid (V2G) network, vehicles and charging stations can respectively make better charging and pricing decisions via real-time information sharing. In this research, we study the charging problem in an intelligent transportation system (ITS), which consists of smart-grid enabled charging stations and networked EVs. Each vehicle aims to select a station with the lowest charging cost by considering the charging prices and its location while the objective of a charging station is to maximize its revenue given the charging strategy of the vehicles. We employ a multileader multi-follower Stackelberg game to model the interplay between the vehicles and charging stations, in which the location factor plays an important role. We show that there exists a unique equilibrium for the followers’ subgame played by the vehicles, while the stations are able to reach an equilibrium of their subgame with respect to the charging prices. Therefore, the Nash equilibrium of the Stackelberg game is achievable through the proposed charging scheme. We further evaluate the price of anarchy (PoA) of the proposed charging scheme by using a centralized optimization model, in which a modified matching algorithm is applied. In state-of-the-art research works, PHEVs tend to charge or discharge to a smart grid individually. In our extended work, we also consider the discharging scenarios for PHEVs, which is generally during the peak hours of a micro-grid system. We propose that by leveraging the cooperation between charging and discharging PHEVs, the grid will be able to properly disperse the charging load in the load valley and discharging during the load peak hours. As a consequence, the electricity load will be well balanced. In this process, the PHEVs also receive greater benefit, thus serving the PHEV charging and discharging cooperation as a win-win strategy for both the grid and the PHEV users. We formulate and resolve the PHEV charging and discharging cooperation in the framework of a coalition game. Finally, simulation results confirm the uniqueness of the equilibrium in both the game strategies. A performance comparison between the proposed distributed and centralized strategy with existing solutions are presented. We also provide the results of the coalition game when both charging and discharging PHEVs are present in the network. The proper management of charging and discharging of EVs poses one of the most challenging and interesting issues in our research. We aim to provide a complete demand response management solution to PHEVs and micro-grids in a real-time scenario.
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- Title
- IMPACT OF DATA SHAPE, FIDELITY, AND INTER-OBSERVER REPRODUCIBILITY ON CARDIAC MAGNETIC RESONANCE IMAGE PIPELINES
- Creator
- Obioma, Blessing Ngozi
- Date
- 2020
- Description
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Artificial Intelligence (AI) holds a great promise in the healthcare. It provides a variety of advantages with its application in clinical...
Show moreArtificial Intelligence (AI) holds a great promise in the healthcare. It provides a variety of advantages with its application in clinical diagnosis, disease prediction, and treatment, with such interests intensifying in the medical image field. AI can automate various cumbersome data processing techniques in medical imaging such as segmentation of left ventricular chambers and image-based classification of diseases. However, full clinical implementation and adaptation of emerging AI-based tools face challenges due to the inherently opaque nature of such AI algorithms based on Deep Neural Networks (DNN), for which computer-trained bias is not only difficult to detect by physician users but is also difficult to safely design in software development. In this work, we examine AI application in Cardiac Magnetic Resonance (CMR) using an automated image classification task, and thereby propose an AI quality control framework design that differentially evaluates the black-box DNN via carefully prepared input data with shape and fidelity variations to probe system responses to these variations. Two variants of the Visual Geometric Graphics with 19 neural layers (VGG19) was used for classification, with a total of 60,000 CMR images. Findings from this work provides insights on the importance of quality training data preparation and demonstrates the importance of data shape variability. It also provides gateway for computation performance optimization in training and validation time.
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