Search results

Title: WIND MICRO-CLIMATE CONFORMATION IN HOT DRY CITIES; RIYADH
Creator: Alhawsah, Saeed Idris
Date: 2019
Description: Recently, the transformation in urban development in Saudi Arabia has caused abrupt and sporadic change to its desert climate. Careful...
Show moreRecently, the transformation in urban development in Saudi Arabia has caused abrupt and sporadic change to its desert climate. Careful environmental consideration of vernacular architecture practices is lost by the vast modernization. The significant changes of modernization contain desertification, sand rapping due to massive urban construction, and urban heat islands, all that has created a severe issue with sandstorms. Saudi’s modernization changed sandstorms phenomena from its seasonal occasions to a frequent rapid increase as a result of the urban inability to maintain its naturally mild and soothing condition. All the global incidents from the natural refugees in Gobi Desert, China, to the 1930s U.S. dustbowl are evident to the urban environmental disturbance. This research is an environmental investigation to reduce the sandstorm effects in Saudi Arabia through designing multiple territorial landscape interventions to filter out the sandstorms and trap its sediments to avoid reoccurring sandstorms.
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Title: Wireless Body Sensor Network for Tracking Human Mobility using Long Short-Term Memory Neural Network for Classification
Creator: Gupta, Saumya
Date: 2019
Description: A large number of sensors are used without justification of the number chosen or placement choice. Many papers about body sensor networks...
Show moreA large number of sensors are used without justification of the number chosen or placement choice. Many papers about body sensor networks explore how to capture a type or types of motion, but all their sensors are placed in different locations; making their algorithms very specific to that movement. In this research, we explore the enhancement of human activity classification algorithm using long short-term memory (LSTM) neural network and wearable sensor network. There are five identical nodes used in the body sensor network to collect data. Each node incorporates an ESP8266 Microcontroller with Wi-Fi which is connected to an inertial measurement unit consisting of triple axis accelerometer and gyroscope sensor board. An analysis on the accuracy that each sensor node provides separately and in different combinations has been conducted to allow future research to focus their positioning in optimal positions. A Robot Operating System (ROS) central node is used to illustrate the in-built multi-threading capability. For demonstration, the positions chosen are waist, ankles and wrists. The raw sensor data can be observed on screen while it is being labelled live to create fitting dataset for developing an artificial neural network. Expectation is that increasing the number of sensors should raise the overall accuracy of the output but that isn’t the case observed, positioning of the sensor is pertinent to improvement. These platforms can be further extended to understand different motions and different sensor positions, also expanded to include other sensors.
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Title: CULTURALLY SENSITIVE HELP-SEEKING AMONG ASIAN INTERNATIONAL AND ASIAN AMERICAN COLLEGE STUDENTS
Creator: Tsen, Jonathan Yee-jon
Date: 2020
Description: Asian populations are rapidly rising, representing the fastest growing racial group of immigrants in the U.S. with many seeking higher...
Show moreAsian populations are rapidly rising, representing the fastest growing racial group of immigrants in the U.S. with many seeking higher education. While many face risk for poor mental health outcomes and high suicidal ideation, Asian college students report lower rates seeking mental health services than White Americans. The purpose of this study was to test a culturally sensitive help-seeking model for Asian international and Asian American college students, and to capture relevant psychological and cultural factors that influence help-seeking. This study used an observational design to build on the current research and evaluated the effects of acculturation, enculturation, public stigma of help-seeking, self-stigma of help-seeking, and attitudes on willingness to seek psychological services. Four hundred and fifty-eight students (Age M = 23.93, SD = 4.36) represented by 265 Asian International Students and 193 Asian American Students. Using a path analysis, results demonstrated a poorly fitted model, suggesting that acculturation, enculturation, public stigma, self-stigma, attitudes, and willingness do not relate significantly to each other when viewed altogether in a model. This remained true even when modifications to the model were made, and when observing the model within only Asian American student sample or Asian international student sample. However, significant direct effects were observed between enculturation and public stigma in the total sample, as well as separately in Asian American or Asian international samples. These findings highlight the importance of exploring with different methodological approaches to gain insight on other important psychological and cultural factors that impact help-seeking among Asian international and Asian American college students.
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Title: IDENTIFICATION OF BAX∆2 FRAMESHIFTING REGION VIA DUAL LUCIFERASE ANALYSIS
Creator: Reiner, Katherine
Date: 2020
Description: The antitumor protein Bax is susceptible to microsatellite instability (MSI) mutations that alter its open reading frame by changing Baxs’...
Show moreThe antitumor protein Bax is susceptible to microsatellite instability (MSI) mutations that alter its open reading frame by changing Baxs’ microsatellite of eight guanines (G8) to seven guanines (G7). This mutation results in a frameshift that is corrected by alternative splicing, making Bax∆2. Evidence shows that non-MSI mutated full length Bax∆2 (Bax∆2 G8) can be found in tissue. However, the extra guanine in Bax∆2 should result in premature termination of protein synthesis. Therefore, we believe that Bax∆2 is capable of +1 frameshifting to correct the out of frame sequence caused by splicing. The dual luciferase assay system is a useful tool for measuring frameshifting and in this study, we cloned full length Bax∆2 G8 into a dual luciferase vector to analyze frameshifting. Using this method, we found that the full length Bax∆2 G8 sequence has 3.5% frameshifting activity. To further determine whether the frameshifting occurs in or near the G8 microsatellite, we focused on several truncated constructs containing the first three exons. The results from dual luciferase assay showed that frameshifting activity was high in the constructs containing the G8 microsatellite but diminished when the G8 microsatellite region was removed. Surprisingly, constructs containing exon 4 and 5, which are away from the predicted frameshifting region, also showed frameshifting activity. One possibility to explain these results is that mRNA structures, which are critical to frameshifting, could be altered by construct truncation and consequently lead to artificial frameshifting. Thus, using truncated constructs may not be a viable option for testing frameshifting activity. To maintain mRNA integrity, point mutations within the full sequence, could be a better option to identify the frameshifting site.
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Title: MULTIYEAR AUTOMATED ANALYSIS OF AURORAL IMAGES TO CATEGORIZE IONOSPHERE IRREGULARITY LAYER
Creator: Stuart, David Jacques
Date: 2020
Description: This thesis presents a method of automated analysis of auroral all-sky images (ASIs) to determine the ionospheric layer of plasma...
Show moreThis thesis presents a method of automated analysis of auroral all-sky images (ASIs) to determine the ionospheric layer of plasma irregularities. These irregularities can perturb radio signals in an effect called scintillation, degrading and at worst preventing signal reception. One key question about scintillation-causing irregularities is whether they occur in the E or F layer of the ionosphere, whose dynamics differ.Previous studies have shown Global Positioning System (GPS) scintillation to be correlated with aurorae. The Scintillation Auroral GPS Array (SAGA) at Poker Flat Research Range, Alaska, was used to detect thousands of GPS L1 and L2C scintillation events over 2014-2015. Collocated auroral images of emissions are recorded nightly by both a keogram spectrograph (measuring intensity along a single longitude vs time) and an ASI filtered at 630.0 nm (red), 557.7 nm (green), and 427.8 nm (blue) wavelengths.In this work scattering layers are hypothesized based on optical measurements, through automated filtering of keograms followed by spectral analysis of aurorae, which tend to occur with these irregularities. A cloud detection method using the North-South keogram is implemented, where a time-averaged, intensity-corrected characteristic snapshot of cloudy times was built as a baseline response, and used as the gain in a flat field correction-like step to normalize the cloudy sky appearance. The coefficient of variation Cv is used as the test statistic to determine cloudy times. Cloud-free ASIs have the location of scintillating PRNs identified, and the ratio of red oxygen 630 nm to blue nitrogen 428 nm emissions in that direction. With an auroral model of characteristic energy, ratios above 0.5 are categorized E-Layer and ratios below F-Layer.Multiyear ASI irregularity layer determinations are used to categorize 364 of the initial 4174 SAGA scintillation events. A 77% majority of the events are hypothesized to be F-Layer based on ASI spectral classification. This disagrees with prior PFISR categorizations, which found scintillation events to be majority E-layer. This presents an outstanding question as to the possible reasons for the difference.
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Title: AN ACCELERATING COUETTE FLOW IN NEK5000: APPLICATIONS IN OCEANOGRAPHY AND MAGNETOHYDRODYNAMICS
Creator: Miksis, Zachary M.
Date: 2017, 2017-05
Description: Nek5000 is a highly scalable spectral element code used in a broad array of problems in computational fluid dynamics. In this thesis, we focus...
Show moreNek5000 is a highly scalable spectral element code used in a broad array of problems in computational fluid dynamics. In this thesis, we focus on applying the code to a model problem of an accelerating Couette flow, or a hydrodynamic flow between two plates, of which the top plate is accelerating and the bottom plate is stationary, and verifying the numerical methods as applied to this problem. We obtain an analytical solution to the hydrodynamic flow problem, and use this to analyze the effects of changing time step length, the size of the computational mesh, and the computational polynomial order on the accuracy and stability of Nek5000. Additionally, we discuss the addition of an applied magnetic field to the hydrodynamic Couette flow, and provide a formulation for an exact solution to this magnetohydrodynamic problem that can be used to further verify Nek5000 in a similar fashion to the hydrodynamic problem.
M.S. In Applied Mathematics, May 2017
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Title: INFORMATION QUALITY: RESTRUCTURING THE MODERN ACADEMIC LIBRARY FOR RESEARCH ACCURACY
Creator: JURKOWSKI, ODIN L.
Date: 1997-05
Description: Information overload causes problems in accessing information and is becoming more prevalent as technology allows us to store greater amounts...
Show moreInformation overload causes problems in accessing information and is becoming more prevalent as technology allows us to store greater amounts of information, and as researchers produce ever more specialized knowledge. This thesis will begin with a discussion of this overload followed by an examination of statistics gathered at Illinois Institute of Technology (which support the trend of increased interlibrary loan transactions and the rise in information availability). Following a review of the literature in library and information science, psychology, and linguistics, this thesis will discuss some of the solutions to this problem. First, access may be improved by transforming the storage of information from traditional print resources to electronic. Considering the restrictions of the present vendor supplied print resources, the limitations due to present copyright law, and cost comparisons between print and electronic subscriptions, we find a distinct advantage to future electronic access. This access can be improved through the use of electronic journals, full-text/image databases, and virtual libraries. Second, the searching capabilities of information systems can be improved in order to narrow information into more accurate search results. This can be done by advanced indexing, adding value, relevance and ranking, citation analysis to direct the patron towards improved search results, and by taking advantage of hypertext capabilities in order to ease navigation through information systems.
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Title: SELECTING AN EFFECTIVE DELIVERY METHOD FOR MULTIMEDIA-BASED DISTANCE EDUCATION
Creator: BURIAN, ARNOLD
Date: 1998-05

Title: THE EFFECT OF MOOD INDUCTION ON ADOLESCENT SPEECH BEHAVIOR
Creator: LAWRENCE, HALCYON
Date: 2010-12
Description: An experiment was conducted to determine if a sad mood induction procedure using music and self-imagery would produce sad speech in...
Show moreAn experiment was conducted to determine if a sad mood induction procedure using music and self-imagery would produce sad speech in adolescents. The participants were asked to rate their perceived positive and negative affect and they were recorded. reading speech materials. Results indicate that although participants perceived a change in mood from neutral to sad, none of the baseline acoustic correlates of sad speech were identified in their recordings. These results suggest that either participants were not induced into a sad mood by this procedure or that the method of self-reporting is an inadequate assessment for this age group, signaling that more effective ways to measure mood for adolescents should be investigated. Additionally, since most studies on sad speech use actors, the results may indicate that acted speech provides significantly different correlates from emotionally-induced speech. Finally, a similarly valenced mood may have been induced instead of sadness (e.g. "calmness") which possesses different acoustic correlates from sad speech. Whilst the findings suggest that there is need for further research on these issues, this experiment demonstrates that mood inducement procedures (MIPs), primarily used in the field of psychology, can be applied in other domains. For example, MIPs conducted in online environments could provide useful insights into how mood affects users' online behaviors.
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Title: RUNTIME FOR PERFORMING EXACT TESTS ON THE PI STATISTICAL MODEL FOR RANDOM GRAPHS
Creator: Dillon, Martin
Date: 2016, 2016-05
Description: In statistics, we ask whether some statistical model ts observed data. We use a Markov chain proposed by Gross, Petrovi c, and Stasi to...
Show moreIn statistics, we ask whether some statistical model ts observed data. We use a Markov chain proposed by Gross, Petrovi c, and Stasi to perform exact testing for the p1 random graph model. By comparing it to the simple switch Markov chain, we prove that it mixes rapidly on many classes of degree sequences, and we discuss why it is sometimes better suited than the simple switch chain, and try to easily introduce the concepts from the general theory along the way.
M.S. in Applied Mathematics, May 2016
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Title: Fate of Listeria Monocytogenes on Hard-cooked Eggs Treated With Citric Acid
Creator: Zeng, Hui
Date: 2021
Description: Commercially-prepared hard-cooked eggs are available for foodservice and to the public in retail grocers. Potential contamination with...
Show moreCommercially-prepared hard-cooked eggs are available for foodservice and to the public in retail grocers. Potential contamination with Listeria monocytogenes during or after the cooking and peeling steps is of concern since this pathogen can proliferate at refrigeration temperatures. Citric acid is a common preservative used in the food industry to treat hard-boiled eggs (HBEs). The purpose of this project was to evaluate the efficacy of citric acid treatment of HBEs to reduce the population levels of L. monocytogenes during 24 h (treatment trials) and 28 d storage (storage trials) at 5 or 25°C. Fresh eggs were boiled for 12 min, cooled to 4°C, peeled, and stored at 5°C for 24 h prior to experiments. In treatment trials, HBEs were dip inoculated with a 4-strain cocktail of rifampicin-resistant L. monocytogenes resulting in either 4 (low) or 7 (high) log CFU/egg. Eggs were air-dried 10 min, followed by treatment with pH 2.5 citric acid (PHCA) or 0.2 M citric acid (calculated as the molarity resulting in pH 2.5: MCA) at 5 or 25°C for 24 h. In treatment-storage trials, citric acid treatment of HBEs occurred before or after inoculation, followed by 28-d storage at 5 or 25°C. L. monocytogenes populations were enumerated by homogenization of eggs with BLEB and cultivation on BHI/rifampicin agar. Enrichment in BLEB was conducted if the pathogen was below the level of enumeration. Significant differences in the populations of L. monocytogenes due to temperature of the acid treatment (5 or 25°C) or the two citric acids (MCA and PHCA) were determined using Student’s T-test and ANOVA with Tukey’s post-test, p ≤ 0.05. Overall, the largest L. monocytogenes reduction occurred after 6 h treatment of HBEs with PHCA at 25°C (1.59 ± 0.00 log CFU/egg) and after 24 h with MCA at 5°C (1.23 ± 0.54 log CFU/egg) when the pathogen was inoculated at the low and high levels, respectively. In treatment-storage trials, citric acid treatment after HBE contamination resulted in a fewer number of samples where the pathogen was detected compared to when treatment occurred before contamination. Citric acid treatment for 24 h also resulted in a greater number of samples where L. monocytogenes was not detected than the 1 h treatment. The results of this study determined that L. monocytogenes could survive on HBEs treated with citric acid, regardless of treatment or storage temperature and acid concentration (PHCA or MCA).
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Title: Using population-level data to examine between-group health differences among transgender and cisgender United States military veterans
Creator: Woodward, Honor
Date: 2021
Description: Some subgroups of military veterans, including those with marginalized identities, may be especially vulnerable to poor health. This...
Show moreSome subgroups of military veterans, including those with marginalized identities, may be especially vulnerable to poor health. This hypothesis is supported by the Minority Stress Theory framework, which posits that disparities in health can be attributed to the stress that minority individuals experience as a result of discrimination, prejudice, and oppression (Meyer, 1995; Meyer, 2003). A specific, potentially marginalized group of veterans that is under-explored regarding health is transgender veterans. Using data from the 2019 U.S. Behavioral Risk Factor Surveillance System (BRFSS), the current study hypothesized that transgender U.S. military veterans will report worse health than cisgender U.S. military veterans. Using case control matching, groups of transgender veterans (n = 124) and cisgender veterans (n = 104) were compared on several population-relevant health outcome measures. Chi-square tests of independence were conducted to test for significant differences between transgender and cisgender military veterans on the likelihood of experiencing certain health conditions, engaging in certain health behaviors, and utilizing health care services. Independent samples t-tests were used to test continuous health outcomes, such as self-reported mental health, physical health, and access to health care services. Gender identity was significantly associated with only one health outcome variable, with transgender veterans being more likely than cisgender veterans to have received a formal depression diagnosis (p = .01, phi = .17). No significant differences emerged between transgender and cisgender veterans on continuous health outcome variables. This suggests that previous literature on health disparities between transgender and cisgender individuals may not be generalizable to transgender veterans.
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Title: Frictional behavior of bronze-graphite composite as sliding element in the base isolation system
Creator: You, Da
Date: 2021
Description: There are many calamities around the world, one of the most dangerous disasters is earthquake which threatens the safety of people and the...
Show moreThere are many calamities around the world, one of the most dangerous disasters is earthquake which threatens the safety of people and the structures. Almost every year, there are a lot of property losses and casualties caused by earthquakes. To mitigate the bad effect of the earthquake, the base isolation system was proposed by previous researchers. With the contribution of many researchers, several seismic isolations have been developed. Until now, many structures have installed seismic isolations to resist seismic energy and vibration. The seismic isolation system works well during the earthquake period, and it does help reduce the casualty and property loss induced by earthquakes. There are two main types of bearings used in the seismic isolation system. One is the elastomeric bearings and the other is the sliding bearings. The mechanics of the seismic isolation system preventing the influence of the earthquake and reducing the horizontal acceleration of the structure is to elongate the natural frequency of structure. As for the sliding bearings, the simplest way to increase the period is to reduce the friction coefficient of the two sliding elements. In conventional, two stainless steel plates are commonly used in the pure flat sliding bearing. This study tries to use bronze-graphite composite in the sliding bearing to decrease the friction coefficient.Consequently, the testing results suggest that the bronze-graphite composite has a lower friction coefficient, especially the graphite acting as a lubricant. The friction coefficient of the bronze-graphite plate is in the range of 0.12 to 0.23 under the load of 160 kg - 800kg. With a higher ratio of graphite to bronze at the sliding surface, the effect of reducing the friction coefficient more obviously. And the friction coefficient changes during the increasing loads period. It decreases at the beginning, and starts to increase at a certain load applied on it. Finally, it is reasonable to bronze-graphite composite in a low rise structure which has a relatively low weight. Because the load applied in the test is not high enough, the consequence may not work for high or heavy structure. Taken together, the use of new material with similar properties in the seismic isolation system can help improve the performance of resisting the earthquake. It should be accounted for further research in this field.
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Title: EXPERIMENTAL AND STRUCTURAL STUDIES OF FDA APPROVED EXON SKIPPING TREATMENT DRUGS
Creator: Zhang, Jingwen
Date: 2021
Description: DMD is an X-chromosome related genetic disease caused by loss of dystrophin protein expression, and which impacts 1 in 5000 boys born in the...
Show moreDMD is an X-chromosome related genetic disease caused by loss of dystrophin protein expression, and which impacts 1 in 5000 boys born in the world. The usual cause of this at the genetic level is a frame shift due to internal deletions of one or more exons that results in a change of the reading frame. This results in loss of expression of the protein encoded by this gene, dystrophin, which in turn leads to the disease phenotype. Exon skipping is a therapy for DMD which restores dystrophin pre-mRNA reading frame to produce a modified dystrophin. This is done by antisense oligonucleotides, AONs, which disturb the process of exon splicing and exclude targeted exons near the patient’s defect which restore the correct reading frame in the pre-mRNA transcript. In 2016, the first AON was approved for clinical use targeting exon 51, called eteplirsen. This provided the first disease modifying therapy for DMD, but it was only relevant to ~6% of patients who had defects that were correctable by skipping this specific exon. In 2020 two more AONs targeting exon 53 were developed, viltolarsen and golodirsen, providing benefit to an additional 5% of patients, and in 2021 casimersen targeting exon 45 was approved.However, this raises an interesting issue, in that for some patients, with an exon 52 deletion, skipping exon 51 or skipping exon 53 could both restore the reading frame. Which approved exon skipping treatment is better and the differences between them are still unknown. This is the aim of this study: to help patients figure out which AON can have a consequence of less long-term health problems like cardiomyopathy and longer life and get more precise treatment. We selected three exon skipped edits – two that represent exon 53 skipping repair of an underlying Δe52 defect and one targeting exon 51 skipping repair of a Δe52 defect. We then used a panel of biophysical and biochemical including dynamic light scattering, circular dichroism Spectroscopy, thermal denaturation, and protease K challenge to investigate the biophysical characteristics of these different exon skipped edits. From our results we found that Δe51-52 has the more structure (i.e., is less perturbed), compared to e52-53, as assessed by CD or by proteinase K challenge, but it also has lower thermal stability, with a low Tm=48C transition that begins to unfold at the physiological relevant temperature of 37C. On the other hand, e52-53 has less helical structure, but what structure did form had unfolding transitions in the normal range for wild type STRs, Tm> 60C; but this edit also had more non-helical structure. So, the total experimental results of these three edits are very complex, which may be due to the fact that these edits span the normally unfolded H3 region.
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Title: HIGH-THROUGHPUT FIRST-PRINCIPLES STUDY ON HIGH-ENTROPY ALLOYS
Creator: Zhang, Jie
Date: 2021
Description: This research thesis discusses the current ecosystem surrounding a new type of alloy: high entropy alloys (HEA) or multi-element crystalline...
Show moreThis research thesis discusses the current ecosystem surrounding a new type of alloy: high entropy alloys (HEA) or multi-element crystalline materials and lays out the high-throughput first-principles calculation as a valuable approach to study these materials. The density function theory (DFT) from computational material science prospect was implemented to investigate the HEAs. Using EMTO-CPA algorithm, high-throughput DFT calculations were conducted. A total of 1958 HEA systems including equimolar and non-equimolar systems were studied with respect to the varies properties, including lattice parameters, bulk moduli, elastic constants, and elastic anisotropy. The first-principles HEA dataset was employed as the training set for the DeepSets a machine learning model. DeepSets, in combination with EMTO-CPA high-throughput calculation, successfully predicted the mechanical properties of specific HEA composition. This paves a promising new path of designing, investigating, and validating the HEA system compared to the time-consuming conventional HEA design method. The doping effect of Vanadium (V) and Titanium (Ti) to NbMoTaW HEA, as well as V or Ti as the fifth element with different molar fraction to the NbMoTaW HEA system, were studied. The phase stability of the new systems was discussed and concluded that all proposed systems tend to form single-phase solid solution. Though the addiction of V only slightly enhances the system’s ductility, the addition of Ti not only enhances the quinary system NbMoTaWTiX (X =0.25, 0.5,0.75, 1.0) ductility, but enables the system to be closer to fully isotropic.
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Title: Sex Differences in a Network Model of Depressive Symptoms
Creator: Ginger, Emily J
Date: 2021
Description: Major Depressive Disorder (MDD) is one of the most prevalent mental health disorders, with a lifetime prevalence rate of 13-16% and 12-month...
Show moreMajor Depressive Disorder (MDD) is one of the most prevalent mental health disorders, with a lifetime prevalence rate of 13-16% and 12-month prevalence rates of 5-7%. It has long been established that the rates of MDD in females is two to three times that of males. Previous research has examined sex differences in the occurrence and severity of MDD symptoms, primarily indicating greater severity of appetite increase and weight gain in females compared to males. The majority of previous research has been conducted assuming the latent factor model that MDD accounts for the symptoms of depression, and sex operates as a mediator or moderator between the latent variable and MDD, or between MDD and its symptoms. The present study used network analysis to examine whether there are sex differences in the relations between symptoms of depression, which might be an important factor for understanding sex differences in prevalence rates of MDD. The present study compared networks of DSM MDD symptoms between currently depressed females and males, and separate networks that also included other symptoms commonly associated with depression (e.g., anxiety, anger). Sex differences were examined using jointly estimated networks, and a Network Comparison Test (NCT) for the independently estimated networks. Results indicated no sex differences in depression symptom networks. These results indicate that depressive symptom networks, or the relations between symptoms are not an important factor for understanding the disparity in sex differences in MDD prevalence rates. Interestingly, non-DSM symptoms were among the strongest and most important symptoms within the network, suggesting future research and diagnostic criteria should consider inclusion of non-DSM symptoms associated with MDD.
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Title: Child Temperament, Attachment, and Loneliness: The Mediating Effects of Social Competence
Creator: Evans, Lindsey M
Date: 2021
Description: Chronic loneliness is a risk factor associated with adverse psychological, physical, and academic outcomes. Converging evidence suggests that...
Show moreChronic loneliness is a risk factor associated with adverse psychological, physical, and academic outcomes. Converging evidence suggests that young children experience and can reliably report on their own loneliness. Due to the significant negative sequalae associated with childhood loneliness, it is critically important to examine risk factors for child loneliness. The aims of this study were two-fold: (a) to examine if temperament (i.e., negative affect, effortful control, and inhibitory control) and attachment security assessed at 4 years of age predict loneliness at age 6; and (b) to determine if social competence at age 5 mediates the relation between temperament and attachment security at age 4 and loneliness at age 6. Participants included a diverse sample of 796 4-year old children, about half of whom were male. At age 4, temperament was assessed with the Rothbart Child Behavior Questionnaire and three inhibitory control tasks, and attachment security was assessed with the Attachment Q-Sort. At age 5, the Social Skills Rating Scale was used to assess social competence, and, at age 6, loneliness was assessed with the Loneliness and Social Dissatisfaction Questionnaire. Results of hierarchical regression analyses indicated that lower levels of effortful control and inhibitory control at age 4 significantly predicted higher levels of loneliness at age 6. Also, lower levels of negative affect and higher levels of effortful control and attachment security at age 4 significantly predicted higher levels of social competence at age 5. However, social competence at age 5 did not predict loneliness at age 6. There was no evidence that social competence at age 5 mediated the relation between age 4 temperament, attachment security and age 6 loneliness. These findings reveal that early self-regulation is associated with later child-reported loneliness and that intervention for children who struggle with cognitive regulation may be effective in decreasing risk for later loneliness.
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Title: Inviscid Shock Propagation within a Variable-Geometry Scramjet Inlet
Creator: Grybko, Maciej
Date: 2021
Description: The study concerns the propagation of shockwaves within an inlet of a scramjet engine and effect of inlet geometry variation on performance. A...
Show moreThe study concerns the propagation of shockwaves within an inlet of a scramjet engine and effect of inlet geometry variation on performance. A Python code was developed to simulate and visualize a flowfield within a scramjet inlet, based on inviscid oblique shock theory. The program was validated against NASA Shock software, and the results differed only by round-off error (0.05%). Subsequently a geometric sensitivity study was conducted, showing that throughout acceleration from Mach 5 to Mach 20 parameters like inlet height could be varied to ensure constant number of shocks within an inlet (preventing discontinuous changes of flowfield), whereas lower wedge angle could control compression required for optimal combustion. Correspondingly, a trajectory was determined with a constraint on static pressure entering combustion chamber (100 kPa). For an arbitrary baseline inlet geometry, it was established that beyond Mach 10 the scramjet would exceed structural load limit, despite delivering sufficient conditions for rapid combustion. Nevertheless, below Mach 10 it would operate efficiently, proving that hydrocarbon-fueled scramjets can have a fixed geometry. For higher speeds, a variable geometry is a necessity.
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Title: ARE SUPPORTIVE FOSTER CAREGIVERS ASSOCIATED WITH IMPROVED FOSTER CARE ALUMNI OUTCOMES? A LONGITUDINAL EXAMINATION OF THE EFFECT OF SUPPORTIVE FOSTER CAREGIVERS ON MENTAL HEALTH OUTCOMES IN A NATIONALLY REPRESENTATIVE SAMPLE
Creator: Dunn, Megan Reeves
Date: 2021
Description: Foster youth are a vulnerable population associated with poor health outcomes, but relatively little research has identified factors that may...
Show moreFoster youth are a vulnerable population associated with poor health outcomes, but relatively little research has identified factors that may mitigate adverse outcomes for these youth. The present study augments previous research by utilizing a nationally representative, longitudinal study (The National Longitudinal Study of Adolescent to Adult Health or Add Health) to investigate whether foster youth in the United States face significantly different mental and behavioral health outcomes compared with same-age peers, and second, whether presence of a supportive foster caregiver may predict better mental and behavioral health outcomes in the foster youth subsample. Using data from Waves III and IV of the Add Health study (N = 12,288 participants, of which n = 282 were foster youth), analyses examined whether foster status and higher caregiver support was related to rates of depression symptoms, suicidal ideation, marijuana use, and alcohol use. Surprisingly, there were few differences between those with and without a foster history; higher frequency of marijuana use among foster youth was the only significant difference. However, analyses in the foster youth subsample indicated that the presence of a supportive caregiver was associated with lower rates of depression symptoms and lower endorsement of suicidal ideation, demonstrating caregiver support as a possible protective factor for foster youth. Future research must continue to explore potential benefits of caregiver support, as it may inform policy that can improve long-term outcomes for foster youth.
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Title: THE EFFECTS OF MODIFIED SURFACES ON INSULIN CRYSTALLIZATION
Creator: Hammadi, Okba Tahar
Date: 2021
Description: Engineered nucleation features (ENFs) were designed with the hope to improve the efficiency of protein crystallization and increase...
Show moreEngineered nucleation features (ENFs) were designed with the hope to improve the efficiency of protein crystallization and increase reproducibility both in quality and quantity. These ENFs were tested with human insulin as the protein of choice since it has flexible parameters, only one cofactor, and a large amount of commercially available crystal ready protein. Insulin crystallization on the ENFs will produce more crystals while also having a reduced crystallization on-set time compared to the control glass surface. The ENFs were compared to control surfaces under similar conditions and observed over time to record both onset-times and end times. The ENFs performed markedly better in on-set times, having an overall 87%-time reduction when compared to the control drops. The drops placed on the ENF produced more than 2.5x the number of crystals in the control drops.
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