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Title: SPECIFICITY OF DEFICITS IN EXECUTIVE FUNCTIONING IN YOUTH WITH NONVERBAL LEARNING DISABILITY, ATTENTION DEFICIT HYPERACTIVITY DISORDER AND READING DISORDER
Creator: McCue, Kimberly Ann
Date: 2021
Description: Nonverbal Learning Disability (NLD) has been the focus of four decades of neuropsychological research. However, it has yet to be included as a...
Show moreNonverbal Learning Disability (NLD) has been the focus of four decades of neuropsychological research. However, it has yet to be included as a diagnostic category in the Diagnostic and Statistical Manual of Mental Disorders (i.e., currently in its fifth edition, DSM-5, American Psychiatric Association, 2013). Many of the characteristics associated with Nonverbal Learning Disorder (NLD) are similar to those found in other more established disorders such as Attention-Deficit/Hyperactivity Disorder (ADHD), Specific Learning Disorders (SLD), and Autism Spectrum Disorder (ASD). Recent research in neuropsychology and other fields has contributed to a greater understanding of the cognitive profiles of NLD, ADHD, and Reading Disorder (RD). However, the neurological underpinnings of deficits in executive functioning specific to NLD versus ADHD and RD have yet to be fully elucidated. Ongoing research has failed to distinguish NLD from other childhood disorders, including ADHD, based on specific structural or functional neurological deficits. The current study examined the specificity of deficits in executive functioning in youth with nonverbal learning disability, attention deficit hyperactivity disorder and reading disorder. In addition, the study examined the degree to which the Rey Complex Figure Test subscales and Processing Speed Index (PSI) and Working Memory Index (WMI) scores (WISC-IV or WISC-III) could discriminate between the NLD group from ADHD and RD groups. Data for the present study were collected from a population served by the Pediatric Neuropsychological Service at The University of Chicago Medicine. Children who had been referred for neuropsychological assessment and whose comprehensive battery included a WISC measure (WISC-III or WISC-IV) and RCFT measurements were included. All data were archival, i.e., gleaned from the Service database; data from 202 participants was retrieved, including youth who underwent neuropsychological evaluation between 2003 and 2016. The present study hypothesized differences between NLD, ADHD, and RD diagnostic groups on visuo-spatial planning/organization, visuo-spatial working memory, long-term visuo-spatial recall, visuo-spatial recognition, verbal working memory, and processing speed. In summary, of the six executive function domains examined, two domains showed significant underperformance for the NLD group, two domains showed a non-significant trend of underperformance for the NLD group and two domains did not show significant differences between diagnostic groups.
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Title: BURNOUT AMONG SEXUAL MINORITIES: THE ROLE OF CONCEALMENT, RUMINATION, AND ORGANIZATIONAL NON-DISCRIMINATION POLICIES
Creator: Burke, Margaret
Date: 2021
Description: Employee burnout is detrimental to individuals (e.g., physical and mental health concerns), as well as to organizations (e.g., diminished...
Show moreEmployee burnout is detrimental to individuals (e.g., physical and mental health concerns), as well as to organizations (e.g., diminished performance). Although numerous studies have examined burnout across a variety of industries and populations, there are limited studies that have examined burnout specifically among sexual minority employees, referring to lesbian, gay, bisexual, transgender, and queer (LGBTQ) workers. This study integrated Meyer’s (2003) Minority Stress Model and Hatzenbuehler’s (2009) Psychological Mediation Framework to investigate the role of concealment, rumination, and non-discrimination organizational policies on burnout among 406 sexual minority employees working in a variety of industries (e.g., healthcare, retail, education, etc.). To test the relationships between these variables, a mediation model and a mediation with moderation model was tested using Hayes’ (2018) Process macro. Results indicated that concealing one’s sexual orientation at work was positively related to rumination, and in turn, was positively related to burnout. Contrary to one of the hypotheses, organizational non-discrimination policies that were inclusive of sexual minorities did not moderate the relationship between concealment and burnout. Previous research, implications, and limitations to this study are discussed in detail.
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Title: Computational study on the heme scavenging ability of Staphylococcus aureus IsdH receptor: Utilizing molecular dynamics to understand an unknown mechanism
Creator: Clayton, Joseph Alan
Date: 2021
Description: Methicillin-resistant Staphylococcus aureus (MRSA) has become an infamous pathogen with infection rates that have declined slowly in recent...
Show moreMethicillin-resistant Staphylococcus aureus (MRSA) has become an infamous pathogen with infection rates that have declined slowly in recent years. S. aureus requires iron as a metabolic nutrient during infection and obtains this nutrient through an iron-regulated surface-determinant (Isd) system that extracts iron from the host’s heme stored in hemoglobin (Hb) through near iron transporter (NEAT) domains. This work concentrates on studying the second and third NEAT domains of IsdH by utilizing atomistic molecular dynamics to probe the heme scavenging process; in collaboration with the Clubb Group at UCLA, we discover key functional regions of IsdH and describe fundamental interdomain dynamics. In addition, I investigate a conventional computational method to describe protein dynamics and propose an alternative that aims to alleviate computational effort by incorporating experimental data.
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Title: INVESTIGATION OF STRUCTURE AND PROCESSING EFFECTS ON THE ELECTROCHEMICAL PERFORMANCE OF COBALT-FREE, LITHIUM- AND MANGANESE-RICH LAYERED OXIDE CATHODE FOR LIBS
Creator: Kucuk, Kamil
Date: 2021
Description: Rechargeable Li-ion batteries (LIBs) have been widely used in a diverse range of energy storage systems because of their high energy and power...
Show moreRechargeable Li-ion batteries (LIBs) have been widely used in a diverse range of energy storage systems because of their high energy and power density, low self-discharge, and tolerable memory effect, compared to the conventional alkaline, lead acid, and nickel-cadmium (Ni/Cd) batteries. [2] Since not only cathodes materials control the energy density of a cell, but also the capacity of cathode material characteristically restricts the cell capacity (as well as about 40% of the cell cost results from the cost of cathode raw materials), the majority of studies on LIBs have been carried out on developing alternative cathodes with higher energy, lower cost, and more environmentally friendliness. [2], [3] From this perspective, both Co-free and lithium- & manganese-rich (LMRO) layered oxide MNF cathodes, Li1.2(MnxNiyFez)O2, have recently attracted great attention in lithium-ion battery (LIB) research for electric vehicles and energy storage devices due to their high capacities of over 250 mAhg−1 and being eco-friendly and inexpensive compared to the cobalt-based Li-rich Li1.2(NixMnyCoz)O2 and Ni-rich Li(NixMnyCoz)O2 (NMC), and LiCoO2 commercial cathodes. Replacing toxic and expensive Co in the LMRO cathodes with environmentally friendly and much cheaper Fe element has been extensively studied over the last two decades. It was suggested by Aryal, S. et. al., in 2018. [4] that the Li1.2(Mn0.50Ni0.20Fe0.10)O2 (MNF502010) Co-free LMRO MNF cathodes seem better in terms of capacity-retention with higher discharge capacity and less voltage fade compared to other MNF compositions. However, the MNF502010 cathode still suffers from its lower experimental capacity, compared to its expected theoretical capacity (270-455 mAhg−1), as well as capacity decay, voltage fade, poor rate capability, and thermal instability. In this dissertation, it is reported that comparable specific discharge capacity with less amount of voltage fading and capacity decay can be achieved by fluorine doping, synthesizing materials in large amounts (0.1 mol synthesis at least) with two-step firing, and then washing the obtained nanocomposites with H3PO4 to create Li3PO4 layer on the surface of bulk MNF composites. The specific discharge capacity and cycling performance of the Co-free MNF502010 cathodes were studied and enhanced by using and optimizing these approaches in this work for the first time. However, voltage fading and capacity decay are still remaining challenges, even if they are remarkably mitigated by applying these approaches. Structural changes due to layered to spinel transformation, less amount of monoclinic phase activation leading to structural deformation occurring after 1st charge, dissolution of the transition metals (TM), and oxygen release (loss of lattice oxygen) from the MNF material upon following electrochemical cycling at higher voltage (≥ 4.5V ) seem the main reasons behind these challenges, specifically the voltage fading and capacity decay.A series of fluorine-doped/undoped, Co-free MNF502010 nanocomposite cathode materials (Li1.2(Mn0.50Ni0.20Fe0.10)O2(1−x)F2x, briefly F-doped MNF) were synthesized by using a sol-gel technique. Firstly (Chapter 4), the fluorine was substituted for oxygen in the parent MNF compound in different fractions (0.00, 0.025, 0.05,0.075, 0.10, which means 0%, 2.5%, 5.0%, 7.5%, and 10%), in order to optimize the amount of fluorine for better performance; secondly (Chapter 5), a large batch (0.1mol, 10 times more than the previous batch) of 5%F-doped material was prepared by a modified sol-gel synthesis which is modified by heating at 700 ◦C for different time-periods; 7.5 hours (7.5h), 15 hours (15h, two-step firing, 7.5h + rest for 12h + 7.5h), instead of heating directly 15 hours (d15h), as done in the first chapter; finally (Chapter 6), H3PO4 treatment resulting in a non-uniform Li3PO4 layer on the bulk surface. These approaches were respectively applied on doped/undoped MNF502010 nano-composites, in order to overcome the challenges already mentioned above. Finally, the effects of these approaches on the structural, morphological, and electrochemical properties of MNF cathode materials were investigated by means of powder X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) with energy dispersive X-ray (EDS) analysis, X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), galvanostatic charge-discharge cycling, and X-ray absorption spectroscopy (XAS, an element specific probe technique). Specifically, ex-situ XAS was performed at the Mn, Ni, and Fe K-edge and used to detect the changes both in the oxidation state of the transition metal (TM) ions and their local environments in order to get a better understanding of the improved performance of the composite materials, as well as their failure mechanism. Moreover, the EXAFS data were modeled to gain insight into the influence of these approaches on the electrochemical performance of both pristine (uncycled) and cycled electrodes (after the 100th discharge). From correlating the electrochemical performance of the modified/unmodified MNF nano-composite cathodes to their XANES and EXAFS analysis, the ability to achieve higher specific capacity is strongly dependent on the formation of a well-ordered layered structure and the amount of monoclinic component (Li2MnO3) activation resulting in higher redox-activity of the Mn cations. The long-term cyclability or capacity retention can be enhanced by heating the resulting powders with a two-step firing (instead of directly 15 hours) and washing them with 1wt%H3PO4 solution to create a Li3PO4 conductive and protective layer.
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Title: A three-dimensional tissue molecular imaging system based on angular domain optical projection tomography: Applications in lymph node biopsy
Creator: Torres, Veronica Calliste
Date: 2020
Description: Sentinel lymph node biopsy is a good prognostic factor for several cancers as therapeutic decisions are often determined by the results....
Show moreSentinel lymph node biopsy is a good prognostic factor for several cancers as therapeutic decisions are often determined by the results. Despite this importance, false negatives remain common because of standard pathology procedures that aim only to detect macrometastases (> 2 mm diameter) and leave more than 99% of lymph node volumes unassessed. While it is possible to section tissue samples more thoroughly, a subsequent 10x increase in pathologist read time is undesirable. Therefore, a more sensitive and rapid approach for lymph node evaluation is warranted.Our proposed solution was the development of an angle-restricted optical projection tomography system to provide high resolution quantitative imaging of whole lymph nodes prior to conventional pathology. Two main strategies were employed: 1) early photon imaging achieved with angular restriction to minimize the number of detected multiply scattered photons that add to imaging blur; and 2) paired-agent molecular imaging, which can quantify targeted biomolecule concentrations through co-administration of targeted and control imaging agents.This thesis focused primarily on the first aspect; however, all work was performed with paired-agent imaging in mind, such that the technique can be implemented directly in future studies. The first chapter presents a proof-of-concept that verifies the utility of angle-domain imaging for evaluation of low scattering lymph nodes. Filtered backprojection and strict angle restriction for scatter rejection were sufficient to detect and localize clinically relevant metastases. In the second chapter, improvements were made to the system so that detection efficiency could be improved, and the system was more rigorously characterized in terms of reconstruction accuracy and limits of detection. Finally, the third chapter presents the investigation of alternate reconstruction techniques to push the limits of achievable resolution and image quality. The overall findings of this work demonstrate the potential for an angle-restricted tomography system to provide significant improvements of metastases detection sensitivity in excised lymph nodes compared to conventional pathology at a fraction of the time and cost.
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Title: FIELD EMISSION MITIGATION VIA IN-SITU PLASMA PROCESSING IN 1.3 GIGAHERTZ 9-CELL LCLS-II CAVITIES
Creator: Giaccone, Bianca
Date: 2021
Description: Field emission (FE) is one of the limiting factors in superconducting radiofrequency cavities' performance. It is known that even a few...
Show moreField emission (FE) is one of the limiting factors in superconducting radiofrequency cavities' performance. It is known that even a few monolayers of surface adsorbed contaminants can lower the niobium work function and increase the FE. In order to address the field emission that may arise once the accelerator is already assembled, it was decided to develop plasma processing for the Linac Coherent Light Source II, a method to mitigate field emission in-situ. Starting from Doleans's successful experience with plasma processing for high beta cavities, Fermi National Accelerator Laboratory is developing plasma cleaning for TESLA shaped 1.3 GHz 9-cell cavities. A new method of ignition based on the higher order modes and couplers was developed, along with a detection procedure that allows to identify the location of the plasma inside the cavity. In this work are presented the results of plasma processing applied to 1.3 GHz cavities, both single-cell and 9-cells. The cavities were contaminated with multiple sources, naturally or artificially, and their performance was measured through cryogenic RF tests before and after plasma cleaning. These experiments proved that plasma processing successfully removed hydrocarbon-related field emission from cavities artificially contaminated, but also from a cavity with natural and unknown FE source. In some cases of more extreme contamination through vacuum failure simulation conducted in air (not in a cleanroom), plasma processing was not able to recover the cavity's performance. An ongoing analysis of the cavity contaminants is presented here, explaining the reason why some contaminated cavities showed little improvement after plasma processing. A microscopic study of the effect of plasma processing on the niobium surface is also presented. Niobium samples prepared with different surface treatments were analyzed using X-ray photoelectron spectroscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The samples were subjected to plasma processing and analyzed again, in order to draw a comparison and identify possible surface changes caused by the reactive oxygen contained in the glow discharge. The samples were prepared with different surface treatments in order to understand if plasma processing may affect them differently. This study showed a possible increase in the oxide thickness after plasma processing and a reduction of the energy difference between the pentoxide and the metal peaks. In preparation for this study, the near-surface region of one niobium sample was investigated with X-ray photoelectron spectroscopy at various steps of sputtering and subsequent oxide regrowth in air. The results showed that the majority of the oxide is composed of Nb2O5, however, the presence of two suboxides (NbO, NbO2) is observed, plus an additional peak (attributed to Nb2O) measured both during sputtering and oxide regrowth.
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Title: Moksha Tower
Creator: Fu, Yalin
Date: 2011-03, 2010-05
Description: In India, death is considered one of the most important stages of the whole human process.And the traditional funeral process occupied a great...
Show moreIn India, death is considered one of the most important stages of the whole human process.And the traditional funeral process occupied a great quantity of land in a country with a big population.Moksha tower(cemetery tower) created a high-rise cemetery in order , to free up previous ground floor cemetery green space for recreation. This would create a vertical resource for the handling and disposal of dead bodies, which would provide storage for the dead for only limited a period of time, in order to ensure adequate capacity to continually accommodate new dead.
Sponsorship: Wood, Antony
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Title: ADVANCING OPEN-SOURCE TOOLS FOR INDOOR ENVIRONMENTAL MONITORING AND BUILDING SYSTEMS CONTROLS USING WIRELESS SENSOR NETWORKS
Creator: Ali, Akram Syed
Date: 2021
Description: Incorporating data monitoring and visualization tools in buildings can provide a glimpse into their energy use, thermal performance, daily...
Show moreIncorporating data monitoring and visualization tools in buildings can provide a glimpse into their energy use, thermal performance, daily operation, and maintenance requirements. However, buildings have traditionally been monitored using hardware and software that are expensive, proprietary, and often limited in terms of ease of use and flexibility. Many existing buildings remain unmonitored or poorly monitored, leaving many opportunities for energy savings and improving indoor environmental conditions unaddressed. To this end, the goal of this research is to develop and demonstrate an open-source hardware and software platform for monitoring and controlling the performance of buildings and their systems, called Elemental. It is designed to provide real-time data on indoor environmental quality, energy usage, heating, ventilating, and air-conditioning (HVAC) operation, and other factors to its users, and provide easy development of building controls. It combines: (i) custom low power printed circuit boards (PCBs) with RF transceivers for wireless sensors, control nodes, and USB gateway, (ii) a Raspberry Pi with custom firmware acting as a backhaul, and (iii) custom software applications that manage data storage, device configuration and interface for querying and visualizing the data in real-time. The platform is built around the idea of a private, secure, and open technology for the built environment. Among its many applications, the platform allows occupants to investigate anomalies in energy usage, environmental quality, and thermal performance. It also includes multiple frontends to view and analyze building activity data, which can be used directly in building controls. This proposal describes the development process of the hardware and software used in the Elemental platform along with three distinct applications including: (1) deployment in a research lab for long-term data collection and automated analysis, (2) use as a full-home energy and environmental monitoring solution, and (3) building heating system automation at the room-level with the development and deployment of a custom radiator control. Through these applications, this work demonstrates that the platform allows easy and virtually unlimited datalogging, monitoring, and analysis of real-time sensor data with low setup costs. Low-power sensor nodes placed in abundance in a building can also provide precise and immediate fault-detection, allowing for tuning equipment for more efficient operation and faster maintenance during the lifetime of the building.
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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: GROWTH KINETICS OF LISTERIA MONOCYTOGENES DURING REHYDRATION OF DEHYDRATED PLANT FOODS AND SUBSEQUENT STORAGE
Creator: Wu, Zihui
Date: 2020
Description: 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: Attitudes of Adults Treated for Depression Toward Technology-Assisted Therapy
Creator: Johnston, Winter D.
Date: 2021
Description: Depression is associated with functional impairment (Saarni et al., 2007), high economic costs (Cuijpers et al., 2007; Greenberg & Birnbaum,...
Show moreDepression is associated with functional impairment (Saarni et al., 2007), high economic costs (Cuijpers et al., 2007; Greenberg & Birnbaum, 2005), and loss of quality of life (Rapaport et al., 2005), and has been named a major reason for illness-related disability worldwide (Vos et al., 2013). Barriers to treatment include being physically limited to access services (Apolinario-Hagen et al., 2018), fear of stigmatization, desire to handle the problem on ones’ own, lack of confidence in the healthcare system (Königbauer et al., 2017), lack of motivation to change, and negative perception of psychological and/or drug treatments (Richards et al., 2015). As technological options have advanced and become more reliable, they have become tools to improve access to care and reduce barriers. Clinicians’ attitudes have been studied pertaining to incorporating different technology modalities into traditional therapy; however, client attitudes are less explored. The present study aims to (1) explore client attitudes towards hypothetical technology-assisted interventions, (2) assess the relative preferences for various technology-assisted interventions, (3) identify correlates of the participant’s preference of different technology-assisted interventions, including: (a) attitudes towards technology-assisted therapy, (b) sociodemographic variables, (c) help-seeking variables (seeking health information, use of technology outside therapy, awareness of technology-assisted options for therapy), (d) previous therapy experience (therapeutic approach, helpfulness of therapy, number of previous therapists), and (4) assess if working alliance with participants’ most recent therapist moderated the effect of therapist condition (current/recent or new) on preferences. The technology options in this study are videoconferencing, online therapy, mobile phones, and virtual reality/avatars. Individuals were asked to imagine continuing therapy using these technological options. Participants viewed videos demonstrating how each technology is used in a therapeutic setting and provided their attitudes and preferences afterwards. The participants consisted of adults who currently or in the recent past have received therapy to treat any severity of depression. Overall, participants had a positive attitude towards technology-assisted therapy. Participants’ relative preference for various technology-assisted interventions and their first-choice modality of therapy did not differ by whether the participant was to keep their same therapist or start therapy with a new therapist. A variety of determinants were associated with greater preference towards the different modalities. Lastly, the strength of working alliance did not moderate whether preferences differed based on staying with the participant’s current/most recent therapist or starting with a new therapist. Limitations, strengths, and conclusions are also discussed.
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Title: ENERGY METABOLISM OF CHLAMYDIA PNEUMONIAE
Creator: McMillan, B. Julia
Date: 2021
Description: Chlamydia pneumoniae is a gram-negative bacterium that infects the humanrespiratory tract. It causes acute pneumonia and has been linked to...
Show moreChlamydia pneumoniae is a gram-negative bacterium that infects the humanrespiratory tract. It causes acute pneumonia and has been linked to several chronic diseases including cardiovascular disease, asthma, and some neurological diseases. C. pneumoniae primarily exists in two forms, the elementary body (EB) and the reticulate body (RB). The EB infects host cells and the RB replicates inside them. In order to survive in and out of the host, it was thought that C. pneumoniae RBs obtain host ATP to use for energy, making it an “energy parasite.” However, genomic analysis indicated that it was also possible for C. pneumoniae to create ATP from its own respiratory chain using the Na + pump NADH Ubiquinone Oxidoreductase (Na + -NQR). Neither the details of the energy parasite theory nor the possibility of C. pneumoniae creating its own energy had been experimentally explored. This project used a pharmacological approach to explore C. pneumoniae host energy consumption at various developmental stages, examine a mechanism that the bacterium could use to produce its own energy, and assess the importance of a balanced Na + /H + gradient for energy production and maintaining homeostasis. Based on the genomic analysis, it was thought that C. pneumoniae would rely heavily on host ATP in the EB form but not the RB form, that inhibiting Na + -NQR would slow bacterial growth, particularly in RBs, and that disrupting the Na + /H + gradient would significantly reduce RB infection. The results indicate that in the EB form, C. pneumoniae relies on host ATP and requires a balanced Na + /H + gradient, but disrupting Na + -NQR does not hinder its growth. In the RB form, C. pneumoniae is not dependent on host ATP, nor on its own respiratory chain ATP, and is not impacted by an unbalanced Na + /H + gradient. Therefore, the energy parasite hypothesis appears to apply to C. pneumoniae EBs but not RBs. Furthermore, established C. pneumoniae infections are excellent at compensating for various environmental conditions and sources of energy, which proves challenging for drug design against C. pneumoniae.
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Title: TOWARD A MODERN CIVIC MONUMENTALITY: ARCHES, VAULTS, AND DOMES IN POSTWAR AMERICAN ARCHITECTURE
Creator: Amado Petroli, Marcos
Date: 2021
Description: This dissertation studies the use of arcuated structures in post-World War II American civic buildings, which serve both to answer the...
Show moreThis dissertation studies the use of arcuated structures in post-World War II American civic buildings, which serve both to answer the practical and functional demands of the architectural program, and to communicate a distinct and hierarchical character inherent to the very genesis of civic architecture. This research demonstrates how a generation of multicultural architects, educated in the academic tradition, with the collaboration of structural engineers, participated in the expansion of the syntax and vocabulary of modern architecture at a time when the language of monumentality was also being discussed. In doing so, they moved away from a Bauhaus-German doctrine that promoted a universal, orthogonal, and homogeneous architectural language, serving all types of buildings. In this context, this research redefines the relationship between academic tradition and modern approaches to monumentality in American architecture, which are usually seen as antagonistic languages. To test the hypothesis that these new arched forms, of high structural engineering, were linked to both modern and academic aspects, and more precisely, French roots, this research addresses three main issues: (i) the mistrust of the new monumentality, which was often mystified and associated with totalitarian regimes; (ii) the analysis of this production through pioneering case studies in postwar arched structures; and (iii) the relationship between academic tradition and modern architecture, with an emphasis on the theory of "architectural character." Finally, this research concludes that the construction of this civic monumentality in the United States was not only a rational response to special programs and an opposition to the universal character of modern buildings, but also the result of an immigration of more inclusive ideas, which, reacting with the local tradition and heritage of the Beaux-Arts system, gave rise to an autochthonous American production.
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Title: Towards a Self-Programmable Storage Solution in Extreme-Scale Environments
Creator: Devarajan, Hariharan
Date: 2021
Description: Traditional compute-centric scientific discovery has led to a growing gap between computation power and storage capabilities. However, in the...
Show moreTraditional compute-centric scientific discovery has led to a growing gap between computation power and storage capabilities. However, in the data explosion era, where data analysis is essential for scientific discovery, slow storage systems led to the research conundrum known as the I/O bottleneck. Scientists have proposed several optimizations to address the I/O bottleneck. However, selecting and applying the appropriate optimization is a complex task, often left to the users. Additionally, the explosion of data has led to the proliferation of applications as well as storage technologies. This has created a complex matching problem between diverse application requirements and heterogeneous storage resources for the users. We need to move towards a Self-Programmable storage system that can automatically understand the I/O requirements of applications, transparently leverage the heterogeneity of storage, and reconfigures itself dynamically by utilizing application and storage information. In this work, we present the Jal System for building Self-Programmable storage. The Jal System consists of three layers: the application layer, the transfer layer, and the storage layer. The application layer uses automatic extraction of I/O requirements from applications using a source-code-based profiler. The storage layer defines a data abstraction, using a shared log store, to efficiently unify heterogeneous storage resources under a single platform. Finally, the transfer layer defines data management algorithms that consider multi-application and multi-storage information to optimize data operations. Additionally, we illustrate the benefits of utilizing the technologies within the Jal System on modern scientific AI applications. Our evaluations have demonstrated that each technology within the Jal System can accelerate I/O for modern scientific workflows. We have implemented software, tools, and system libraries for modern HPC systems. In the future, we envision building a fully integrated system that efficiently utilizes all the Jal System technologies. Additionally, we plan to extend the strategies and techniques in Jal System to other scientific domains such as AI and IoT.
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Title: MITOCHONDRIA RELOCALIZATION IN CHLAMYDIA TRACHOMATIS INFECTED HFF-1 CELLS
Creator: Shuppara, Alexander Mitchell
Date: 2021
Description: Chlamydia trachomatis is an infectious, gram-negative, obligate intracellular human bacterial pathogen. With over eight hundred million cases...
Show moreChlamydia trachomatis is an infectious, gram-negative, obligate intracellular human bacterial pathogen. With over eight hundred million cases worldwide, C. trachomatis is the most prevalent sexually transmitted infection. It manifests as either trachoma, lymphogranuloma venereum, or other urogenital tract sequelae. As an intracellular pathogen, Chlamydia must scavenge for essential metabolites from establishing networks with its host’s organelles including Golgi apparatus, endoplasmic reticulum, endocytic vesicles, mitochondria, and the cytoskeleton. C. trachomatis was considered an “energy parasite” that is entirely dependent on their host’s ATP production. Yet, recent mitochondrial inhibitor-based evidence suggests that C. trachomatis possess a sodium-based energy gradient for ATP production. Despite this finding, literature on specific interactions between host cell mitochondria and C. trachomatis requires further definition. This project evaluates mitochondrial dynamics changes from C. trachomatis infection in the human foreskin fibroblast cell line, HFF-1. We first defined C. trachomatis growth characteristics in HFF-1 over 36 hours-post infection. Next, we determined changes in mitochondrial dynamics and content throughout infection using immunofluorescent and immunoblotting techniques. observations on infected cells show mitochondrial morphology changes from an elongated appearance at the early stages of infection to fragmented in the late infection stages. Unlike in HeLa cells, HFF-1 remains in a normal distribution throughout the cell and we do not observe mitochondria relocalizing toward the inclusion. By studying mitochondrial relocalization dynamics, new insights into the dynamic and parasitic relationship of Chlamydia and its host can be discovered.
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Title: Reconfigurable High-Performance Computation and Communication Platform for Ultrasonic Applications
Creator: Wang, Boyang
Date: 2021
Description: In industrial and medical applications, ultrasonic signals are used in nondestructive testing (NDT), medical imaging, navigation, and...
Show moreIn industrial and medical applications, ultrasonic signals are used in nondestructive testing (NDT), medical imaging, navigation, and communication. This study presents the architecture of high-performance computational systems designed for ultrasonic nondestructive testing, data compression using machine learning, and a multilayer perceptron neural network for ultrasonic flaw detection and grain size characterization. We researched and developed a real-time software-defined ultrasonic communication system for transmitting information through highly reverberant and dispersive solid channels. Orthogonal frequency-division multiplexing is explored to combat the severe multipath effect in the solid channels and achieve an optimal bitrate solution. In this study, a reconfigurable, high-performance, low-cost, and real-time ultrasonic data acquisition and signal processing platform is designed based on an all-programmable system-on-chip (APSoC). We designed the unsupervised learning models using wavelet packet transformation optimized by convolutional autoencoder for massive ultrasonic data compression. The proposed learning models can achieve a compression accuracy of 98% by using only 6% of the original data. For ultrasonic signal analysis in NDT applications, we utilized the multilayer perceptron neural network (MLPNN) to detect flaw echoes masked by strong microstructure scattering noise (i.e., about zero dB SNR or less) with detection accuracy above 99%. It is of high interest to characterize materials using ultrasonic scattering properties for grain size estimation and classification. We successfully designed an MLPNN to classify the grain sizes of materials with an accuracy of 99%. Furthermore, a software-defined ultrasonic communication system based on the APSoC is designed for real-time data transmission through solid channels. Transducers with a center frequency of 2.5 MHz are used to transmit and receive information-bearing ultrasonic waves in solid channels where the communication bit rate can reach up to 1.5 Mbps.
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Title: Modeling the Aerodynamic Response to Impulsive Active Flow Control
Creator: Asztalos, Katherine
Date: 2021
Description: In unsteady aerodynamics the response to external disturbances can depend significantly on the initial condition, and the extent to which this...
Show moreIn unsteady aerodynamics the response to external disturbances can depend significantly on the initial condition, and the extent to which this impacts the ability to model the flowfield can vary. In this work, we look to develop a model that can capture and predict the long-time response to actuation, which we suspect to be sensitive to the instantaneous state. We investigate whether a physical understanding of the short-time response to impulsive actuation can be obtained, with the goal of understanding the observed physical phenomenon present in the immediate response to this type of actuation. We find that the response to impulsive actuation is sensitive to the instantaneous wake, and that the short-time response is directly proportional to the time rate of change of the actuation input. Computational simulations of a stalled NACA 0009 airfoil subject to leading-edge synthetic jet actuation were performed. Full state information, as well as force response measurements, were collected using an immersed boundary method (IBM) numerical code. The numerical simulations performed sought to characterize the response to actuation by varying the actuation parameters, such as the strength, direction, and phase at which the onset of actuation occurs. It was found that the long-time response to actuation can be sensitive to the instantaneous wake state at the onset of actuation. The ability to extract models that describe the complex behavior of the system provides additional insight into the dominant features governing the response of such systems, as well as achieves predictive capabilities of the systems' response. The data-driven models, which are identified using variants of dynamic mode decomposition, can capture both the short- and long-time response of the system to actuation. Predictive models are identified using multiple trajectories of data corresponding to varying the phase of vortex shedding at which the onset of actuation occurs. These models achieve accurate predictions for off-design cases as well. It is also shown that multiple control objectives with the same actuator can be achieved. Classical theory aids in understanding the physics governing unsteady aerodynamic motion and the response to disturbances. Theoretical models are developed using the assumptions from classical unsteady aerodynamic theory, which provide insight into the forms that the data-driven models take. The effect of short-duration momentum injection actuation is modeled through a combination of source/sink, doublet, and vortex elements. Regardless of the precise elements used in the theoretical model, the lift response is composed of a contribution directly proportional to the rate of change of actuation strength, and a contribution that persists after the actuation burst ends that arises due to the enforcement of the Kutta condition. Methodologies that retain the physics inherent to the system by projecting the governing equations of motion onto a well-suited basis are extremely valuable for gaining physical insight and understanding into the dynamics of the flowfield. A new methodology is proposed for extracting spectral content from systems with limited data available using projection-based modeling approaches. There are challenges associated with using modal decomposition-based modeling techniques for systems exhibiting large transient dynamics due to external inputs, which is applicable in this particular instance and for related systems. The methodology presented here shows how the dynamics of this system can be understood through analysis of optimal finite-time horizon transient energy growth, applied to reduced-order models identified using actuation response data with either data-driven or physics-based models. A novel methodology is proposed to guide future experimental actuation design to achieve maximal response by considering an optimal forcing mode, identified from considering the optimal perturbation of the full unactuated system, which maximizes a given output.
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Title: Effects of the Silicon Content on the Dimensional Changes of Electrodes for Lithium-ion Cells: An Electrochemical Dilatometry Study
Creator: Rodrigues Prado, Andressa Yasmim
Date: 2021
Description: The continuous growth of the electric vehicle market has significantly increased the demand for Li-ion batteries (LIBs). However, state-of-the...
Show moreThe continuous growth of the electric vehicle market has significantly increased the demand for Li-ion batteries (LIBs). However, state-of-the-art LIBs are not yet able to meet the EV industry demand for high energy density and long cycle life rechargeable batteries, prompting efforts to improve the performance of Li-ion cells. In this context, silicon became the most promising next-generation active material for LIBs negative electrodes, especially because Si can significantly increase the lithium storage capacity of the commonly available anodes. Nonetheless, commercialization of Si-based electrodes has been hindered by the poor electrochemical performance of these electrodes, which is mainly attributed to the severe volumetric changes in the silicon particles related to the electrochemical reactions with Li. Since the electrodes are composites with a complex combination of various materials interspaced by pores, the electrode-level swelling may differ significantly from the particle-scale expansion. Furthermore, an increase in electrode thickness due to silicon expansion can have a direct effect on how Li-ion cells are designed, as the accommodation of electrode dilation requires additional cell space to prevent significant dynamic stresses. Thus, the actual volumetric energy density of a LIB cell depends on the electrode swelling, since the higher the magnitude of the electrode expansion, the lower the gains in energy density. Monitoring the electrode dilation is just as important as the electrochemical evaluation when designing cells with Si-based anodes.In this work, we use high-resolution operando electrochemical dilatometry to quantify the (de)lithiation-induced expansion/contraction of silicon, blended silicon-graphite and graphite electrodes, upon electrochemical cycling. We evaluate the relationship between electrode capacity and dilation and observe that while the lithiation capacity improved with increasing the silicon content, the electrode swelling is highly aggravated. For silicon-rich anodes, the electrode dilation can be higher than 300%, and the expansion profile consists of a combination of slow swelling at low levels of lithiation followed by an accelerated increase at higher lithium contents. This non-linear dilation allows for narrowing the swelling by limiting the electrode capacity. In addition, we investigate how electrode properties, such as porosity, affect the dilation profile, and quantify the irreversible expansion of the electrodes. Finally, we discuss some of the challenges associated with the dilatometry technique and suggest experimental approaches for obtaining consistent and reliable data.
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Title: On the Study of Successful Derivatives: A Holistic Approach to the Standardization of Financial Innovation
Creator: Schoinas, Konstantinos Georgios
Date: 2021
Description: This dissertation attempts a contribution toward a much-needed holistic understanding surrounding the trading dynamics of exchange-based...
Show moreThis dissertation attempts a contribution toward a much-needed holistic understanding surrounding the trading dynamics of exchange-based derivative products. The latter proxying such products’ commercial performance. Hence, upon identifying the lack of a measurement standard as the underlying reason for the attested and motivating knowledge deficit, we adopt a two-step approach for the development thereof: At first an integrated conceptual framework is established and, subsequently, a normalization standard is derived. In result, across-product trading dynamics are rendered directly comparable; arguably, for the first time ever. Furthermore, we also explore the existing postulation of balanced liquidity commitments between the groups of hedgers and speculators and posit the construct of a corresponding temporarily stable equilibrium. The latter serves as the first dimension on which the developed measurement standard may be applied. Accordingly, we conduct empirical research predicated on an extensive dataset with daily trading activity and, just as theorized, reject the hypothesis that the aforementioned speculator-hedger ratio is non-stationary. We then proceed in studying the trading dynamics of individual derivatives, implementing the developed standard by means of longitudinal analyses for second time. To a large extent our results do not contradict the body of related literature, which however has been essentially based on heuristic approaches to this time. Nevertheless, in its course, this study also highlights the need to shift the entire paradigm of studying individual derivatives trading success – from a single-faceted – to two separate effects: one anchored to the short term ‘steam gathering’ capacity of newly launched products and another associated with the notion of established products’ longevity. Altogether then, this study aspires to serve as a solid first step in systematically answering Webb’s (2018) call to confront the still unknown causes of derivatives’ success, or lack thereof.
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Title: Evaluation of Bax∆2 Positive-Staining in Skin Samples Using Two Immunohistochemical Methods
Creator: Basheer, Sana
Date: 2021
Description: BaxΔ2 is a pro-death and tumor suppressor protein that sensitizes cells to certain chemotherapies. Previous diaminobenzidine (DAB)-based...
Show moreBaxΔ2 is a pro-death and tumor suppressor protein that sensitizes cells to certain chemotherapies. Previous diaminobenzidine (DAB)-based staining revealed that Bax∆2 is found in all organs, including breast, colon, and skin tissues. In the skin, the Bax∆2 positive cells were mainly found in the basal cell layer of the epidermis with a few Bax∆2 positive cells in the connective tissue of the dermis, although their cellular identity was unknown. Previous literature has shown that melanin, which is found throughout the cells of the epidermis, is a brown color that provides no visual contrast to the DAB staining. While the DAB-based immunostaining showed cells that appeared to be Bax∆2 positive, this result needed to be confirmed. For this, a set of human skin samples from normal and cancerous tissue of various patients was examined. The co-staining of these samples for Bax∆2 and basal cells using immunofluorescence revealed that the apparent Bax∆2-positve DAB staining in epidermal basal cells and squamous cell carcinoma as false-positive, but the Bax∆2 positive cells found in the dermal connective tissue were not false positive—which is consistent with both previous DAB-based and fluorescence-based immunostaining. Using co-immunostaining for Bax∆2 with different cellular markers, the Bax2-positive cells in the connective tissue were identified potentially as macrophages and fibroblasts. Further studies are required to confirm the identity of the Bax∆2 positive cells in the connective tissue.
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