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Title: THE CONTRIBUTIONS OF SPATIAL, VERBAL, AND ANALYTICAL SKILLS TO PROBLEM-SOLVING PERFORMANCE
Creator: Foster, Ardyth C.
Date: 2012-12-18, 2012-12
Description: ABSTRACT The purpose of this study was to examine the existence and strength of relationships between students’ cognitive skills and...
Show moreABSTRACT The purpose of this study was to examine the existence and strength of relationships between students’ cognitive skills and mathematical problem-solving performance. Specifically, relationships between students’ verbal, spatial, and analytical skills and their problem-solving performance on items that require a verbal response, items that require a spatial response, and overall problem-solving performance were investigated. A review of the literature also revealed assumptions of close links between verbal and logical/analytical skills, resulting in a lack of assessment of these skills as separate constructs. This study therefore sought to measure each of the cognitive skills separately in order to clearly establish the existence and strength of any pair-wise relationships among the cognitive skills. Ninety-eight students from the fifth- through eighth-grades were administered assessments of verbal skills, spatial skills, and logical/analytical skills, as well as a problem-solving instrument that consisted of a verbal (PST-Verbal) subtest and a spatial (PST-Spatial) subtest. The results indicated statistically significant relationships between students’ cognitive skills and problemsolving performance on the PST-Verbal subtest, the PST-Spatial subtest, and overall problem-solving performance. Surprisingly stronger relationships were found, however, between spatial skills and PST-Verbal performance than between verbal skills and PSTVerbal performance, and stronger relationships were found between verbal skills and PST-Spatial performance than between spatial skills and PST-Spatial performance. Statistically significant pair-wise relationships were also found among the cognitive skills, with the strongest pair-wise relationship existing between verbal and analytical viii skills. The relationship between verbal and spatial skills, although not as strong as the one that exists between verbal and analytical skills, was also quite strong.
PH.D in Mathematics Education, December 2012
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Title: WIRELESS SENSOR NETWORK BASED BUILDING AUTOMATION SYSTEM
Creator: Yi, Peizhong
Date: 2012-07-11, 2012-07
Description: Smart grid adds intelligence and bidirectional communication capabilities to today’s power grid, enabling utilities to provide real-time...
Show moreSmart grid adds intelligence and bidirectional communication capabilities to today’s power grid, enabling utilities to provide real-time-pricing (RTP) information to their customers via smart meters. This facilitates customer participation in demand response programs to reduce peak electricity demand. ZigBee, as a wireless technology characterized by low cost, power, data rate, and complexity, is ideal for smart grid applications. Unfortunately, almost all ZigBee channels overlap with Wireless Local Area Networks (WLAN) channels, resulting in severe performance degradation. In this dissertation, firstly, practical ZigBee deployment guidelines under WLAN interference are presented. “Safe Distance” and “Safe Offset Frequency” are identified by means of a comprehensive approach consisting of theoretical analysis, software simulation, and empirical measurement. In addition, a frequency-agility based interference avoidance algorithm is proposed and is implemented. The proposed algorithm detects interference and adaptively switches nodes to “safe” channels dynamically to avoid interference with low latency and energy overhead. Later we propose a real-time residential demand response scheme based on price information provided by ZigBee enabled smart meters. We model the price signal as a random process with known deterministic components, and formulate the problem of cost-minimization as a stochastic scheduling problem. A constraint on the total power consumption is considered to avoid peak shifting. An opportunistic scheduling algorithm consisting of two stages is proposed. Each user is tentatively scheduled based on the optimal stopping approach as if there is no power constraint at the first stage, while the power constraint is taken into account at the second stage. The proposed scheduling algorithm can be implemented in either a centralized or distributed fashion. Simulations validate proposed scheme can evidently reduce the cost of electricity users. At last, an optimal and automatic residential load scheduling scheme with distributed storage system based on our price prediction scheme is proposed. The price prediction scheme forecasts the future 24-hour prices according to day-ahead pricing and RTP history. Our designed scheme adopts integer programming computation to provide simple solution for customers to minimize the total cost including electricity expenditure and storage degradation while satisfying customer time requirement. The performance of proposed scheme is then evaluated through simulation.
Ph.D. in Electrical Engineering, July 2012
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Title: CHAIN BY CHAIN MONTE CARLO SIMULATIONS FOR POLYMERIZATION PROCESSES
Creator: Demirel, Derya
Date: 2016, 2016-05
Description: Predicting chain microstructure became an important task for polymer scientists. Polydisperse nature of polymer molecules makes it an...
Show morePredicting chain microstructure became an important task for polymer scientists. Polydisperse nature of polymer molecules makes it an interesting research area. In this work, a new method, called “Chain-by-Chain Monte Carlo Method” (CBCMC), is presented for simulating chain microstructures one-by-one or chain-by-chain. To the best of our knowledge, it is a new approach for the simulation of chain microstructures. It is a hybrid deterministic-stochastic method that uses the best of two worlds by obtaining information on the mean-field background environment as concentrations of polymer populations and small molecules (only) from the deterministic solver and using it in the stochastic part of the algorithm. Deterministic solver can employ any method that provides this data and in this work uses method of moments. With this information, stochastic part of the algorithm employs kinetic Monte Carlo algorithm to simulate chains one-by-one. The computational load of simulating the whole ensemble is eliminated by getting the mean-field background information from deterministic solvers as concentrations of polymer populations and small molecules at certain time intervals. CBC-MC is suited for chemistries, or situations in which the chain architecture develops slowly with respect to the background environment such as controlled reversible-deactivation radical polymerizations. This method is applied to two case studies for synthesis of linear gradient copolymers. First case study is a styrene/ methyl methacrylate copolymerization by nitroxide-mediated polymerization with forced gradient techniques and the second one is the synthesis of methyl methacrylate/ methyl acrylate hyberbolic gradient copolymerization by atom-transfer radical polymerization again with forced gradient techniques. Gradient distribution of chain properties is analyzed in all cases since it is relatively more challenging and interesting. Chain properties such as number average chain length, weight average chain length, polydispersity index, cumulative and instanteneous copolymer compositions, full molecular weight distributions and sequence length distributions are obtained and compared to results from method of moments and kinetic Monte Carlo methods for di↵erent sample sizes. Results were in good agreement with wellestablished method of moments and kinetic Monte Carlo methods. Importance of simulating chain microstructure rather than average properties is made clear. Simulation times were reduced by at least a factor of six compared to kinetic Monte Carlo method. Results confirm that if applicable, full information regarding the microstructure of chains can be obtained using this method with reduced simulation times and smaller sample sizes. This method is also applied to non-linear copolymerization of acrylamide/N,N-methylenebis(acrylamide) (AM/BisAM) leading to gelation. The e↵ect of a gradient distribution of pendant double bonds along the primary chains on the simulated portion of gel molecules is investigated with the aim of detecting the macro-heterogeinities. Five cases are studied with di↵erent feeding policies but same total number of comonomers introduced to each of them. Primary chain results are compared with MOM for cumulative and instantaneous BisAM compositions, crosslink and PDB densities and found to be in excellent agreement. Further investigations are done on primary chain microsturctures to better understand multiple phenomena going on in these systems such as the age distribution of crosslinking points and PDBs, density of crosslinking points and PDBs in monomer bins along the primary chains and average segment lengths. It has been found that a gradient in PDB distribution along the primary chains can introduce heterogeneities into the gel molecules in surface-bound type polymerizations where primary chains within gels are aligned in the same direction but these heterogeneities seem to be disappearing in bulk polymerizations where the chain alignments are random.
Ph.D. in Chemical Engineering, May 2016
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Title: FPGA IMPLEMENTATION OF QR DECOMPOSITION ALGORITHMS USING HIGH-LEVEL SYNTHESIS ON ZYNQ SOC
Creator: Desai, Parth
Date: 2017, 2017-05
Description: Matrix decomposition and computation constitute an important part of various signal processing, image processing, and communication systems. A...
Show moreMatrix decomposition and computation constitute an important part of various signal processing, image processing, and communication systems. A better solution in terms of power, performance, and area, can lead to improved performance of the whole system. Designing and testing a new idea is a big challenge due to time limitations. So, a better implementation flow using High-Level Synthesis is discussed. This flow is used to implement QR decomposition algorithms. Three different QR factorization techniques, Gram-Schmidt, Givens Rotation, and Householder Transformation is discussed. These algorithms are compared in terms of area, performance, and precision. All the algorithms are implemented with two different variations in terms of the data type used. A 32-bit floating-point implementation and 16-bit fixed-point implementation are discussed. Results for different designs with various optimization techniques like loop unrolling and pipelining are presented. A scalable architecture is implemented for all the algorithms which are compared for a 10 × 10 matrix architecture. Results for scaled up 100 × 100 matrix architecture are also discussed for the Gram- Schmidt algorithm. Gram-Schmidt had the best performance in all. The performance of Gram Schmidt algorithm was improved by a factor of 3 for 10 × 10 matrix size and by a factor of up to 10 for 100 × 100 matrix size using different optimizations. Givens rotation was close in terms of performance, but the Householder Transformation was four times slower compared to other two algorithms, the reason being the high complexity of the algorithm. All floating-point implementations had nearly 100% precision but varied from 3% to 5% in average error for fixed-point data-type for a 10 × 10 implementation. All the algorithms were coded in C++ and synthesized using High-Level Synthesis using Xilinx Vivado HLS 2016.4 tool. This generated an IP core which was imported to Xilinx Vivado 2016.4 for implementation. The design was targeted for Zedboard, a Zynq – 7020 Extensible Processing Platform (EPP) Development Kit, which has a 7 series Xilinx FPGA architecture and a dual core ARM Cortex A-9 processor.
M.S. in Computer Engineering, May 2017
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Title: GRAIN BOUNDARY ENGINEERING OF POWDER-PROCESSED NI-BASE SUPERALLOY RR1000
Creator: Detrois, Martin
Date: 2016, 2016-05
Description: Grain boundary engineering (GBE) has been used to improve the properties of various polycrystalline materials by optimization of their grain...
Show moreGrain boundary engineering (GBE) has been used to improve the properties of various polycrystalline materials by optimization of their grain boundary network. Traditional processing routes for GBE often require multiple iterations of cold work followed by short annealing cycles where each iteration imparts a modest increase in the fraction of special grain boundaries. Multiple iterations are then required to achieve sufficiently high fractions (>50%) that result in the improved properties. Thus, this GBE approach is not suitable for the fabrication of large, complex-shaped structures and leads to added manufacturing lead time and cost. In this investigation, the Ni-base superalloy RR1000 used as turbine discs in gas turbine engines manufactured by Rolls-Royce, was considered for GBE using alternative processing routes more suitable to the forging of Ni-base superalloy components. A preliminary study of the e↵ects of hot deformation parameters closer to typical industrial processing revealed that the length fraction of ⌃3 boundaries increased from 35% to 52% following a single deformation/anneal cycle. Deformation parameters that resulted in strain accommodation via superplastic flow did not enhance the formation of ⌃3 boundaries upon annealing. Whereas deformation parameters that resulted in a dominant dislocation-based plasticity flow mechanism promoted the formation of annealing twins. Using misorientation maps and by estimating the stored strain energy from deformation, equations for the length fraction and density of ⌃3 boundaries were generated for high-temperature GBE of RR1000. The grain boundary characters obtained via high-temperature deformation, however, are less ideal than those resulting from traditional cold rolling. The underlying mechanisms responsible for the formation of ⌃3n boundaries during high-temperature GBE were further investigated. A larger starting grain size prior to deformation was found to be unfavorable to the formation of twin boundaries from twin-reorientation and annihilation of preexisting twins. While recrystallization was found to populate the microstructure with grains that contained very few twin boundaries, post-deformation texture was found to promote the formation of ⌃3 boundaries and triple junctions when Goss texture was present. A final consideration of larger scale forgings was used to raise an outlook on the current issues and the potential of high-temperature GBE for turbine engines.
Ph.D. in Materials Science and Engineering, May 2016
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Title: PRE-CLINICAL IN VIVO AND IN VITRO ASSESSMENT OF HEMOSTATIC EFFECTS OF CONTINUOUS-FLOW VENTRICULAR ASSIST DEVICES
Creator: Crandall, Daniel
Date: 2011-07, 2011-07
Description: Heart failure results in significant morbidity and mortality for those afflicted. The current gold standard treatment is allogenic heart...
Show moreHeart failure results in significant morbidity and mortality for those afflicted. The current gold standard treatment is allogenic heart transplantation, however insufficient supply of donor organs limits the effectiveness of this treatment to ideal candidates. This has led to interest in mechanical circulatory support. The most recent generation of devices are smaller, continuous-flow devices with increased durability compared to their predecessors. However, these new devices exhibit increased rates of hemostatic events – both thromboembolic and hemorrhagic. This thesis details an in vivo evaluation of hemostatic parameters in a bovine animal model to evaluate the effect of the ventricular assist device (VAD), and compares these results to what has been seen clinically. Most importantly this thesis has found that bovines do not experience pathophysiologic degradation of high molecular weight Von Willebrand Factor (VWF) as a result of VAD placement, whereas this complication is well documented in humans. This is due to a decreased sensitivity to shear stress induced cleavage of VWF in bovines when compared to humans, as demonstrated in this thesis. Due to the inability to replicate clinical conditions with the bovine animal model, this thesis develops an alternative methodology using an in vitro flow loop using the same human donor blood on all pumps tested. This methodology eliminates the need for interspecies extrapolation; allows for more direct comparisons by eliminating donor variation; and is both cheaper and faster than animal models. This methodology could provide an invaluable option for evaluating hemostatic effects of various pump design parameters.
Ph.D. in Biomedical Engineering, July 2011
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Title: SUBCLONING AND ACTIVITY EXAMINATION OF VARIANT VITREOSCILLA HEMOGLOBINS PRODUCED BY RANDOM MUTAGENESIS
Creator: Raba, Daniel A.
Date: 2015, 2015-05
Description: A comparison of mutant versus wild type versions of the Vitreoscilla hemoglobin gene (vgb) were the focus of this study. E. coli DH5a cells...
Show moreA comparison of mutant versus wild type versions of the Vitreoscilla hemoglobin gene (vgb) were the focus of this study. E. coli DH5a cells were transformed with recombinant pUC plasmids containing either the wild type or one of a series of mutated versions of the vgb gene. The study was conducted in two pmis. In the first part, eight strains in total were tested (one plasmid-free negative control, one vector-only (pUC18) negative control, one wild type positive control (pUC8: 16), and five mutants (pUC vgb M1-4 and pUC18 vgb M3)) and comparisons were made to reveal growth advantage or possible increased Vitreoscilla hemoglobin protein (VHb) expression due to vgb gene mutation. Three different growth assays were carried out to compare growth rates among the eight strains under different oxygen concentration conditions: (1) Luria-Bertani (LB) medium, aerobic growth assay, (2) Terrific Broth (TB) medium, low-oxygen growth assay, and (3) TB medium, microaerobic growth assay. Additionally, a series of carbon monoxide (CO) difference spectra were run to quantify functioning VHb protein concentrations in the different strains grown under each of the aforementioned oxygen concentration conditions. In the second part of the study, the two vgb gene mutants that exhibited the highest growth rates and the wild type version were subcloned into the vector pUC8, transformed into E. coli DH5a cells, and then compared using the CO difference spectrum assay. Five E. coli DH5a strains were tested (one plasmid-free negative control, one vector-only negative control (pUC8), one vgb wild type positive control (pUC8 vgb WT), and two vgb mutants (pUC8 vgb M1 and M3)). Transfmmation of plasmids containing the mutated or unmutated version of the vgb gene was verified through E.Z.N.A. plasmid miniprep with gel electrophoresis and additionally through growth on selective medium containing ampicillin (Amp) [50 micrograms (ug)/ milliliter (ml)]. Contrary to the results obtained by our Australian collaborators, our growth assays and CO difference spectra revealed no growth advantage or increased expression of functioning VHb protein due to any of the vgb mutations.
M.S. in Biology, May 2015
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Title: Decimal Multiplication Architecture for FPGA Implementation
Creator: Krishna Kumar, Ashwitha
Date: 2012-07-23, 2012-07
Description: The hardware support for the Decimal Multiplication is gaining importance in commercial applications including banking, accounting, tax...
Show moreThe hardware support for the Decimal Multiplication is gaining importance in commercial applications including banking, accounting, tax calculations, currency conversion and insurance. In this work, we examine the di erent types of number sys- tems that have been used for executing Decimal Multiplication. A unique signed-digit representation is used for reduced logic and latency. Furthermore, partial product ac- cumulation is performed with Svoboda decimal adder, which is e cient. The imple- mentation of the proposed architecture is modeled using VHDL and then synthesized on FPGA. The hardware resources for this architecture are analyzed. This work presents an important case study for FPGA implementation of Decimal Arithmetic architectures such as ALUs.
M.S. in Electrical Engineering, July 2012
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Title: MICROGRIDS AND DISTRIBUTED GENERATION SYSTEMS: CONTROL, OPERATION,COORDINATION AND PLANNING
Creator: Che, Liang
Date: 2015, 2015-07
Description: Distributed Energy Resources (DERs) which include distributed generations (DGs), distributed energy storage systems, and adjustable loads are...
Show moreDistributed Energy Resources (DERs) which include distributed generations (DGs), distributed energy storage systems, and adjustable loads are key components in microgrid operations. A microgrid is a small electric power system integrated with onsite DERs to serve all or some portion of the local loads and connected to the utility grid through the point of common coupling (PCC). Microgrids can operate in both gridconnected mode and island mode. The structure and components of hierarchical control for a microgrid at Illinois Institute of Technology (IIT) are discussed and analyzed. Case studies would address the reliable and economic operation of IIT microgrid. The simulation results of IIT microgrid operation demonstrate that the hierarchical control and the coordination strategy of distributed energy resources (DERs) is an effective way of optimizing the economic operation and the reliability of microgrids. The benefits and challenges of DC microgrids are addressed with a DC model for the IIT microgrid. We presented the hierarchical control strategy including the primary, secondary, and tertiary controls for economic operation and the resilience of a DC microgrid. The simulation results verify that the proposed coordinated strategy is an effective way of ensuring the resilient response of DC microgrids to emergencies and optimizing their economic operation at steady state. The concept and prototype of a community (networked) microgrid that interconnecting multiple microgrids in a community are proposed. Two works are conducted. For the coordination, novel three-level hierarchical coordination strategy to coordinate the optimal power exchanges among neighboring microgrids is proposed. For the planning, a multi-microgrid interconnection planning framework using probabilistic minimal cut-set (MCS) based iterative methodology is proposed for enhancing the economic, resilience, and reliability signals in multi-microgrid operations. The implementation of high-reliability microgrids requires proper protection schemes that effectively function in both grid-connected and island modes. This chapter presents a communication-assisted four-level hierarchical protection strategy for highreliability microgrids, and tests the proposed protection strategy based on a loop structured microgrid. The simulation results demonstrate the proposed strategy to be an effective and efficient option for microgrid protection. Additionally, microgrid topology ought to be optimally planned. To address the microgrid topology planning, a graph-partitioning and integer-programming integrated methodology is proposed. This work is not included in the dissertation. Interested readers can refer to our related publication.
Ph.D. in Electrical and Computer Engineering, July 2015
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Title: NUMERICAL MODELING AND ANALYSIS OF CAVITATION IN WATER AND LASER-INDUCED PLASMA AMPLIFICATION FOR MICROMACHINING APPLICATIONS
Creator: Dabir-moghaddam, Navid
Date: 2017, 2017-05
Description: Machining processes are needed in many industrial areas. Laser-based machining often has the advantages such as high spatial resolution, no...
Show moreMachining processes are needed in many industrial areas. Laser-based machining often has the advantages such as high spatial resolution, no mechanical tool wear, etc., and has current and potential applications in many areas. The objective of this research work is to conduct physics-based modeling studies to help the understanding of some physical processes relevant to two novel laser-based machining processes: (i) the Ultrasound-assisted water-confined laser micromachining (UWLM) process (proposed by Prof. Benxin Wu), and (ii) the Dual-pulse laser ablation and plasma amplification (LAPA) process for drilling microholes with variable diameters at different depths (proposed by Prof. Yung C. Shin). The models are developed by numerically solving the relevant governing equations, and are tested by comparing with related experimental measurements when available. The specific topics that have been studied include: (i) Bubble evolution close to a solid boundary; (ii) Ultrasound propagation and cavitation in water; (iii) Laser amplification of pre-existing plasma in a microhole and plasma interaction with the hole sidewall.
Ph.D. in Mechanical and Aerospace Engineering, May 2017
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Title: XAFS STUDIES OF RADIATION DAMAGE IN NUCLEAR MATERIALS
Creator: Olive, Daniel Thomas
Date: 2012-11-13, 2012-12
Description: The growing demand for nuclear energy places a high importance on the development of new materials capable of withstanding higher temperatures...
Show moreThe growing demand for nuclear energy places a high importance on the development of new materials capable of withstanding higher temperatures and harsher irradiation conditions than those used in existing reactors. By supporting the development of next generation reactors it also becomes possible to close the nuclear fuel cycle, greatly reducing the amount of waste sent for disposal in deep geologic repositories, where its interaction with the environment is also a matter of interest. In this thesis, X-ray absorption fine structure (XAFS) spectroscopy is used to investigate the local atomic structure of systems of interest to nuclear energy. First, two XAFS studies on environmental materials are presented. Granular activated carbon (GAC) was treated with iron to improve its water remediation properties, specifically with respect to arsenic. XAFS was used to determine the nature of iron coating on the GAC surface, and the method of arsenic bonding to the treated surface. Next, a neodymium precipitate from solubility studies carried out for the Waste Isolation Pilot Plant (WIPP) was analyzed. Neodymium was used as an analog for plutonium in brine solutions. XAFS fitting indicated that the neodymium substituted for calcium in a gypsum lattice, providing information useful for future geochemical modeling. XAFS was also used to study radiation damage in materials. A candidate material for advanced reactor structural materials, modified 9Cr–1Mo, was irradiated to 1, 4, and 10 displacements per atom (dpa). XAFS analyses were performed on the Fe, Mo, and Nb K-edges. Irradiation caused a reduction in coordination for all three elements, but the exact behavior was element specific. Damage around Fe atoms was linear with dose, while damage around xxii Mo atoms saturated at or before 1 dpa. XAFS was shown to provide a useful atomic level description of radiation damage for a complex alloy system. Finally, zirconium carbide and zirconium nitride, candidate materials for advanced fuel claddings were studied at the Zr K-edge. Samples irradiated to 1 dpa retained overall crystallinity, as indicated by transmission electron microscopy (TEM) images but were found to have an increase in dislocation loops compared to their non-irradiated counterparts. XAFS analysis was able to determine the size of the undefected regions, making it a valuable complement to other analysis techniques. xxiii
PH.D in Physics, December 2012
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Title: EFFECTS OF VORINOSTAT AND 17-AAG ON THE ANDROGEN RECEPTOR AND ANDROGEN-INDEPENDENT PROSTATE CANCER CELL SURVIVAL
Creator: He, Di
Date: 2012-10-10, 2012-12
Description: Prostate cancer is one of the leading causes of cancer-related deaths. The AR is known to play an important role in cell proliferation and...
Show moreProstate cancer is one of the leading causes of cancer-related deaths. The AR is known to play an important role in cell proliferation and cell survival during the development of prostate tumors. Chemical and physical removal of androgens is therefore commonly used to treat prostate cancer. AR regulatory drugs, such as Vorinostat and 17-AAG, are FDA-approved drugs designed to down-regulate AR expression and suppress tumor growth. However, the function of the AR in post-castration tumors is not clear. Recently, our laboratory and others have shown that the AR also has a pro-death function, especially in androgen-independent prostate cancer cells. To determine the function of Vorinostat and 17-AAG on AR expression levels and cell survival in androgen-independent prostate cancer cells, we treated 104-R1 cells, an androgen-independent prostate cancer cell sub-line, with either Vorinostat or 17-AAG. We found that both drugs down-regulated AR protein levels, although Vorinostat was more potent than 17-AAG. Neither drug independently caused significant cell death; however, at certain doses, both drugs induced cell morphological changes that correlated with AR expression levels. Interestingly, Vorinostat synergized with Adriamycin, a commonly used chemotherapeutic drug, to induce cell death, while 17-AAG suppressed Adriamycin-induced apoptosis in 104-R1 cells. These data suggest that the drugs that are effective for androgen-dependent prostate cancer might not be suitable for androgen-independent prostate cancer.
M.S. in Biology, December 2012
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Title: WORKPLACE MISTREATMENT, AFFECT, AND THE SEXUAL MINORITY EXPERIENCE
Creator: Discont, Steve
Date: 2017, 2017-07
Description: This study investigates the impact of low-intensity workplace mistreatment on affective outcomes for sexual minority workers. The study was...
Show moreThis study investigates the impact of low-intensity workplace mistreatment on affective outcomes for sexual minority workers. The study was grounded in affective events theory and minority stress theory. Data was composed of survey responses from a convenience sample of 380 U.S. adults who work full-time and identify as sexual minorities. Hierarchical multiple regression analyses revealed workplace incivility and heterosexist microaggressions significantly predicted negative discrete emotional reactions (i.e., anger, disgust, fear, guilt and sadness). Internalized heterosexism moderated the predictor-outcome relationship between incivility and affective disgust, and between heterosexist microaggressions and affective anger, disgust, and sadness, such that individuals with low internalized heterosexism had greater negative outcomes when forms of mistreatment were high. Results are discussed in terms of both their theoretical implications, and practical implications for organizational research and practice.
M.S. in Psychology, July 2017
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Title: AN EFFORT TO DISCOVER NOVEL BACTERIAL DSZ GENES TO HELP IMPROVE THE BIODESULFURIZATION OF CRUDE OIL
Creator: Salazar, Joelle Krieger
Date: 2011-04-25, 2011-05
Description: In this thesis study, soil samples were procured from various locations thought to contain high petroleum content, such as gas stations. Those...
Show moreIn this thesis study, soil samples were procured from various locations thought to contain high petroleum content, such as gas stations. Those samples were enriched for those that contained bacteria that were able to metabolize sulfur-containing compounds, such as DBT. The bacteria were then subjected to various experiments to determine if they possess any or all of the genes (dsz) encoding the three enzymes of the dibenzothiophene desulfurization pathway, as compared with R. erythropolis IGTS8. This feat was accomplished by using both growth experiments on medium containing dibenzothiophene as the sole sulfur source and genomic DNA extraction followed by PCR with dszABC universal primers. The resultant amplified DNA was then ligated to pGEM®-T Easy vector and transformed into electrocompetent E. coli cells. The transformants were subsequently screened and sent for sequencing. Using Blast, the sequences were analyzed. No obvious dsz homologies were identified although homologues in some cases to enzymes involved in sulfur metabolism were found. Several isolates were found to have dsz-like activity via the growth experiments as well as the Gibbs assay, which measures accumulation of the end product of the dsz-encoded pathway, 2-HBP Soil sample #32 showed promise in growth experiments in that the culture grew well in M9 with DBT as the sole sulfur source at temperatures of 30 °C, 37 °C, 45 °C, and 55 °C. Streaking the culture discovered two colonies with distinct morphology that were designated 32-W and 32-Y, for white and yellow colonies. 32-W and 32-Y also grew independently in M9 with DBT. Positive Gibbs Assays were obtained from the cultures 32-mixed, 32-W, and 32-Y.
M.S. in Biology, May 2011
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Title: CURRENT TRENDS IN WINDSTORM IMPACT REDUCTION
Creator: Cutter, Brad
Date: 2012-04-14, 2012-05
Description: Natural disasters effect everyday life not only immediately after the event but long after the community has rebuilt. Since the ultimate goal...
Show moreNatural disasters effect everyday life not only immediately after the event but long after the community has rebuilt. Since the ultimate goal of the structural engineer is predicated on life safety, it would be irresponsible to allow the damages of the 2011 tornado season to go unaddressed. Appropriate research and development must be made into a priority for the governing bodies in charge of funding these activities. The data collected from the 2011 season should be more than enough to raise awareness to those responsible for such decisions. The first portion of this study is dedicated to elaborating on the past developments, current advancements, and speculating on future trends of governing standards. It is also helpful to associate these trends alongside data resulting from seismic activities in our nation, which we know to have great success in numbers. Current tendencies are revealed through a case study of (3) elementary schools built in the aftermath of a disaster stricken community in Flint, Michigan. Seismic provisions found its’ greatest breakthrough following the Long Beach Earthquake of 1933, where it was deemed federal law that all schools must uphold the standard that their structures are capable of withstanding earthquake forces. There should be no doubt that this would similarly prove to be a critical first step in protecting children in communities subjected to high-wind forces. If the successes of seismic provisions have any indication on the possibilities of properly funded research and development, then there should countless lessons to be learned across the range of topics covered here. With the incorporation of a federally funded network of facilities and better research data to rely on, design professionals can begin utilizing more adequate connection details into their structures. It is this top-down approach toward change that should move us closer toward creating sufficient design standards and in effect hitting the main objective of this profession, life safety.
M.S. in Civil, Architectural, and Environmental Engineering, May 2012
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Title: PHYSICS OF LIMITING PHENOMENA IN SUPERCONDUCTING MICROWAVE RESONATORS: VORTEX DISSIPATION, ULTIMATE QUENCH AND QUALITY FACTOR DEGRADATION MECHANISMS
Creator: Checchin, Mattia
Date: 2016, 2016-12
Description: Superconducting niobium accelerating cavities are devices operating in radiofrequency and able to accelerate charged particles up to energy of...
Show moreSuperconducting niobium accelerating cavities are devices operating in radiofrequency and able to accelerate charged particles up to energy of tera-electron-volts. Such accelerating structures are though limited in terms of quality factor and accelerating gradient, that translates—in some cases—in higher capital costs of construction and operation of superconducting rf accelerators. Looking forward for a new generation of more affordable accelerators, the physical description of limiting mechanisms in superconducting microwave resonators is discussed. In particular, the physics behind the dissipation introduced by vortices in the superconductor, the ultimate quench limitations and the quality factor degradation mechanism after a quench are described in detail. One of the limiting factor of the quality factor is the dissipation introduced by trapped magnetic flux vortices. The radio-frequency complex response of trapped vortices in superconductors is derived by solving the motion equation for a magnetic flux line, assuming a bi-dimensional and mean free path-dependent Lorentzian-shaped pinning potential. The resulting surface resistance shows the bell-shaped trend as a function of the mean free path, in agreement with the experimental data observed. Such bell-shaped trend of the surface resistance is described in terms of the interplay of the two limiting regimes identified as pinning and flux flow regimes, for low and large mean free path values respectively. The model predicts that the dissipation regime—pinning- or flux-flow-dominated—can be tuned either by acting on the frequency or on the electron mean free path value. The effect of different configurations of pinning sites and strength on the vortex surface resistance are also discussed. Accelerating cavities are also limited by the quench of the superconductive state, which limits the maximum accelerating gradient achievable. The accelerating field limiting factor is usually associated to the superheating field, which is intimately correlated to the penetration of magnetic flux vortices in the material. Experimental data for N-doped cavities suggest that uniform Ginzburg-Landau parameter cavities are statistically limited by the lower critical field, in terms of accelerating gradient. By introducing a Ginzburg-Landau parameter profile at the cavity rf surface—dirty layer—the accelerating gradient of superconducting resonators can be enhanced. The description of the physics behind the accelerating gradient enhancement as a consequence of the dirty layer is carried out by solving numerically the Ginzburg-Landau equations for the layered system. The enhancement is showed to be promoted by the higher energy barrier to vortex penetration, and by the enhanced lower critical field. Another serious threat to the quality factor during the cavity operation is the extra dissipation introduced by the quench. Such quality factor degradation mechanism due to the quench, is generated by the trapping of external magnetic flux at quench spot. The purely extrinsic origin of such extra dissipation is proven by the impossibility of decrease the quality factor by quenching in a magnetic field-free environment. Also, a clear relation of the dissipation introduced by quenching to the orientation of the applied magnetic field is observed. The full recover of the quality factor by re-quenching in compensated field is possible when the trapped flux at the quench spot is modest. On the contrary, when the trapped magnetic flux is too large, the quality factor degradation may become irreversible by this technique, likely due to the outward flux migration beyond the normal zone opening during the quench.
Ph.D. in Physics, December 2016
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Title: END-TO-END WIRELESS DIGITAL COMMUNICATION SYSTEM OF FPGA BASED SOFTWARE DEFINED RADIO
Creator: Dang, Tuan
Date: 2017, 2017-05
Description: This thesis describes the design and implementation of an End-to- End digital wireless communication system (E2E) system on the ZedBoard Zynq...
Show moreThis thesis describes the design and implementation of an End-to- End digital wireless communication system (E2E) system on the ZedBoard Zynq-7000 Field Pro- grammable Gate Array (FPGA) Development Board with an Analog Devices AD9364 Wideband Transceiver from a model-based design system. Furthermore, we present the design path to reconfigure the software controlled logic blocks for additional functionality such that the E2E system could be rapidly redeployed. A comparison BER vs. distance plot between the QPSK-1/2 and uncoded QPSK shows QPSK-1/2 with BER = 0 up to 14 m while no FEC QPSK has minimum BER ~ 10-5 up to the same distance.
M.S. in Electrical Engineering, May 2017
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Title: Utilizing Concurrent Data Accesses for Data-Driven and AI Applications
Creator: Lu, Xiaoyang
Date: 2024
Description: In the evolving landscape of data-driven and AI applications, the imperative for reducing data access delay has never been more critical,...
Show moreIn the evolving landscape of data-driven and AI applications, the imperative for reducing data access delay has never been more critical, especially as these applications increasingly underpin modern daily life. Traditionally, architectural optimizations in computing systems have concentrated on data locality, utilizing temporal and spatial locality to enhance data access performance by maximizing data and data block reuse. However, as poor locality is a common characteristic of data-driven and AI applications, utilizing data access concurrency emerges as a promising avenue to optimize the performance of evolving data-driven and AI application workloads.This dissertation advocates utilizing concurrent data accesses to enhance performance in data-driven and AI applications, addressing a significant research gap in the integration of data concurrency for performance improvement. It introduces a suite of innovative case studies, including a prefetching framework that dynamically adjusts aggressiveness based on data concurrency, a cache partitioning framework that balances application demands with concurrency, a concurrency-aware cache management framework to reduce costly cache misses, a holistic cache management framework that considers both data locality and concurrency to fine-tune decisions, and an accelerator design for sparse matrix multiplication that optimizes adaptive execution flow and incorporates concurrency-aware cache optimizations.Our comprehensive evaluations demonstrate that the implemented concurrency-aware frameworks significantly enhance the performance of data-driven and AI applications by leveraging data access concurrency.Specifically, our prefetch framework boosts performance by 17.3%, our cache partitioning framework surpasses locality-based approaches by 15.5%, and our cache management framework achieves a 10.3% performance increase over prior works. Furthermore, our holistic cache management framework enhances performance further, achieving a 13.7% speedup. Additionally, our sparse matrix multiplication accelerator outperforms existing accelerators by a factor of 2.1.As optimizing data locality in data-driven and AI applications becomes increasingly challenging, this dissertation demonstrates that utilizing concurrency can still yield significant performance enhancements, offering new insights and actionable examples for the field. This dissertation not only bridges the identified research gap but also establishes a foundation for further exploration of the full potential of concurrency in data-driven and AI applications and architectures, aiming at fulfilling the evolving performance demands of modern and future computing systems.
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Title: Measurement and Control of Beam Energy at the Fermilab 400 MeV Transfer Line
Creator: Mwaniki, Matilda W.
Date: 2023
Description: Linac is the first machine in the Accelerator chain at Fermilab where particles are accelerated from 35 keV to 400 MeV and travel to the...
Show moreLinac is the first machine in the Accelerator chain at Fermilab where particles are accelerated from 35 keV to 400 MeV and travel to the Booster where they are stripped of the extra electrons to become protons. Tuning Linac is performed using diagnostics to ensure stable intensity and energy while minimizing uncontrolled particle loss. I have been revisiting diagnostics in the Linac in order to understand their signals and to ensure their data is reliable. I revisited Beam Loss Monitors (BLMs) for the loss data confidence. For the confidence of energy data there were two approaches. The first approach was time-of-flight measurements using Beam Position Monitors (BPMs) and beam velocity stripline pick-up that provides beam phase data. The second approach used the relation between beam position data from BPMs and dispersion values from MAD-X simulation to calculate energy. Our goal after understanding the data from the Linac diagnostics and finding the data reliable is to control the Linac parameters using Machine Learning techniques to increase the reliability and quality of beam delivered from Linac.
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Title: Ultrasound Image Guided Robot Arm for Targeted Delivery of Therapeutic Drugs and MicroRNA for Cancer Therapy
Creator: Nagarajan Parimala, Abishek
Date: 2024
Description: Molecular imaging has revolutionized medical diagnostics by providing detailed insights into biological processes at the molecular level...
Show moreMolecular imaging has revolutionized medical diagnostics by providing detailed insights into biological processes at the molecular level within the living subject. Ultrasound Molecular Imaging (USMI) has emerged as a promising diagnostic imaging modality by utilizing targeted contrast agents to unveil crucial molecular information, including vascular biomarkers associated with cancer and other diseases. Despite its potential, the transition of Ultrasound Contrast Agents (UCA) from preclinical evaluation to FDA-approved clinical use faces challenges due to the short in vivo half-life of Micro-Bubbles (MBs), necessitating repeated administrations for comprehensive assessments. Moreover, conventional ultrasound imaging methods suffer from limited scanning areas and single-target focus, leading to low throughput in preclinical evaluations.This thesis addresses these challenges by proposing a robot-assisted whole-body scanning pipeline for preclinical evaluations in Ultrasound Molecular Imaging. By integrating a robotic arm into the imaging setup, this approach enhances scanning flexibility and precision, enabling scans across the entire body of a mouse. This extension of the imaging time window allows for comprehensive assessments without the need for repeated contrast agent administrations. Additionally, the ability to simultaneously scan multiple targets within the same session significantly increases the throughput of preclinical assessments, thereby improving the efficiency and reliability of Ultrasound Molecular Imaging in clinical translation.
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