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Knowledge Guided Evolutionary Algorithms in Financial Investing
No full textA large body of literature exists on evolutionary computing, genetic algorithms, decision trees, codified knowledge, and knowledge management systems; however, the intersection of these computing topics has not been widely researched. Moving through the set of all possible solutions - or traversing the search space - at random exhibits no control over how an organism evolves into a new organism that lies within the search space, also known as the mutation process. Employing codified human knowledge, the traversal of the search space may be constrained and directed thereby controlling mutation. This reveals the research question: How can codified human knowledge be integrated into the evolutionary mutation process in order to influence the traversal of the search space In order to investigate the research question, a design science approach will begin with a design artifact by creating DEFINE - Dynamic Evolution in Financial Investment Election. DEFINE employs decision trees as organisms and utilizes ontologies to constrain the mutation process. This research has the potential to reveal new and unexplored methods of employing human knowledge coupled with evolutionary computing to produce quality knowledge management systems. Preliminary experiments reveal an advantage, as measured by increased classification accuracy, to incorporating knowledge in the mutation process and also reveal financial markets follow a path of evolution with less than 10 generations to reach optimal fitness. Additional experiments conclude well-constructed knowledge constrains the mutation process to exercise control over the traversal of the search space whereas poorly-formed or random knowledge has no effect. Employing knowledge into the mutation process demonstrates making small changes in the organism's structure leads to small changes in the organism's function; however, making large changes showed mixed results. Performance, as measured by classification accuracy and number of generations to reach an optimum fitness, is improved by making small changes in the organism structure as opposed to random changes. This research demonstrates the number of years in time series data affects the number of generations required to achieve an optimum fitness. The methods explored in this research are applied to a financial investing scenario and profitability is shown to lie between two common investment strategies
Inhibiting Amyloid Beta Fibrils from Binding to Cells
No full textThe goal of this study was to test in vitro some of the compounds identified previously in our laboratory via in silico screening for their ability to bind to Ab40, change Ab40 fibril structure, inhibit Ab40-cell binding and attenuate Ab40 toxicity to differentiated SH-SY5Y cells. The following inhibitors: NSC91529, NSC60340 and NSC60339, were selected as the top three inhibitors based on their predicted high binding energy to Ab40-fibrils near residues K28 (NSC91519) and N27 (NSC60340 and NSC60339), residues previously identified as important in Ab40 toxicity. The results from transmission electron microscopy (TEM) showed that all inhibitors significantly reduced the size of the Ab40 fibrils, suggesting that the inhibitors bound to the Ab40 fibrils and/or interacted with fibrils in some way. Results from a flow cytometry based binding assay indicated that incubations of cells with all 3 inhibitors led to a significant reduction in the amount of fluorescently labeled Ab40 fibrils bound to cells at concentrations between 50 to 80 nM inhibitor (p<0.05). At higher concentrations of inhibitors, attenuation of Ab40 binding to cells was not observed. Fluorescence measurements of the hydrophobic inhibitors in physiological saline solutions indicated a change in environment of the inhibitors at concentrations above 100 nM, suggesting some self association in solution, a possible reason for the deviation in the usual trend of binding inhibition curves at the same concentrations. The results from toxicity assays showed that the inhibitor NSC60339 only significantly reduced Ab40 fibril toxicity at concentrations of 10 and 100 nM. Both NSC91529 and NSC60340 were able to attenuate the Ab40 fibril toxicity at all concentrations of inhibitor tested between 10 nM and 500 nM (p<0.05). Based on these results, we could not determine if molecules that were predicted to target K28 on the Ab40 fibril were significantly better than molecules that were predicted to target N27 at attenuated Ab40 toxicity. We did not observe any correlation between predicted binding energy and the concentrations at which toxicity or binding attenuation were observe. Neither did we observe any correlation between change in fibril size, binding inhibition and toxicity attenuation. Further experimentation might help identify these correlations. These results suggest that in silico screening to identify molecules that bind to K28 and N27 on the Ab40 fibrils was able to identify molecules which were able to alter Ab40 structure and attenuate Ab40 toxicity in vitro. This approach may be fruitful in identifying new molecules for the treatment of Alzheimer's disease
Structure of the Myristylated Feline Immunodeficiency Virus Matrix Protein
No full textHIV continues to be a major health concern in America. This work investigates the use of felines as a suitable animal model for HIV. Efforts continue to identify animal models that are more affordable than the current standard. The feline/feline immunodeficiency virus (FIV) model system provides a plausible animal model for HIV. To determine the feasibility of felines as a good animal model for HIV, we will compare FIV matrix to HIV matrix. In HIV-1, matrix binds to phosphoinositide PI(4,5)P2 via a 14-carbon myristate group. The structure of myristylated FIV matrix protein has not been elucidated. We hypothesize that FIV matrix has a structure similar to that of HIV-1 matrix. To test this hypothesis, we solved the structure of myristylated FIV matrix protein using solution NMR and compared its structure to unmyristylated FIV matrix and myristylated HIV matrix. Mutations (Q5A, G6S) were made to residues near the N-terminus of matrix protein in order for it to be myrsitylated by yeast N-myristyltransferase. To conduct NMR studies, we identified conditions to keep the protein soluble and stable. Decreasing the temperature of the NMR experiments and using a neutral pH kept the protein soluble and stable enough to collect 2D, 3D and 4D NMR data. Myristylated FIV matrix protein is a globular protein, comprised of 5 alpha helices and 2 beta interactions. A basic patch is present in a region between helix I and II of the protein. The myristate group packs into the protein and is stabilized by interactions with Phe 90, Ile 53, and Leu 60. The myristylated FIV matrix protein is homologous to myristylated HIV matrix protein, despite only 20% sequence identity between FIV MA and HIV MA. Subsequent experiments show that human that N-myristyltransferase can efficiently myristylate wildtype FIV matrix. Interestingly, the myristyl signal used by FIV matrix is fairly uncommon, and is not observed in other lentiviruses. This work provides a foreground for future experiments related to phosphoinositide dependent Gag assembly, studying wildtype myristylated FIV, and the genetics of myristylation across species. Solving the structure of mryistylated FIV matrix provides insight into the similarities between FIV and HIV to better determine if felines serve as a suitable HIV-1 animal model and broaden our general understanding of lentiviruses
A Genomic Approach to Identify the Genetic Basis of Natural Variation in Lifespan and Age Specific Fecundity and their Plastic Responses to Diet in Drosophila melanogaster
No full textGenetically based variation in lifespan and reproduction is pervasive in nature, and both traits are sensitive to changes in diet; however, we still know little about the actual genes influencing natural variation in lifespan and reproduction, and how these genes interact with environmental variables like diet to influence variation in lifespan and reproduction. I used the Drosophila melanogaster Genetic Reference Panel (DGRP), to complete a genome-wide association (GWA) study on lifespan, age specific fecundity, lifetime fecundity and the plastic response of these traits to changes in diet using mated Drosophila females reared as adults on either a high yeast (HY) diet or a low yeast (LY) diet. I identified a large number of candidate polymorphisms associated with each trait, and follow up studies using RNAi stocks validated the influence of a subset of candidates. I found very little overlap in candidate fecundity SNPs between ages, which suggests that the genetic basis of natural variation in fecundity changes dramatically with age. I also found that only 20 SNPs (0.97%) and 88 genes (8.55%) overlapped as candidates for age specific fecundity or lifespan on both diets, which suggests that individual genes influence lifespan and fecundity in a diet specific manner. I used the GWA results to test the predictions of two evolutionary theories of senescence: mutation accumulation (MA) and antagonistic pleiotropy (AP) and the data provide strong evidence in support of MA at the nucleotide level. Finally, I tested the predictions of two hypotheses regarding the genetic mechanisms of phenotypic plasticity by comparing the results of the GWAs on trait means to the results of the GWAs on the plastic response to diet. I found evidence to support both theories, but most of the data supported the gene regulation hypothesis
Exploring Healthcare Consumer Acceptance of Personal Health Information Management Technology - Personal Health Record Systems
No full textHealthcare technologies are evolving from a practitioner-centric model to a patient-centric model due to the increasing need for technology that directly serves healthcare consumers, including healthy people and patients. Personal health information management (PHIM) technology is one of the technologies designed to enhance an individual's ability to manage their personal health information. Healthcare consumers struggle with common challenges of PHIM, but the acceptance of PHIM technology, such as personal health record (PHR) systems, has not yet become widespread. This thesis employed mixed methods to identify and understand the factors that influence healthcare consumer acceptance and usage of PHIM technologies, and to improve the user interface design of PHIM technology from consumers' perspectives. Both quantitative and qualitative methods were applied including 1) questionnaire surveys to identify and measure factors influencing the acceptance and usage of PHIM technologies; 2) interviews for a deeper understanding the critical factors determined from the questionnaire survey, and to explore the solution to improve the user interface from consumers' perspective; and 3) controlled experiments to validate the important factors and the design guidelines determined through the questionnaire survey and interview studies. The research results indicated an overall low usage rate among PHR systems (about 10%). Six factors were identified to be associated with use intention. Perceived usefulness and health information understandability explained 26% of the variance of the use intention (R^2=0.26, p<0.001) in the regression model. Additionally, use intention was found to be associated with personalization (r=0.56, p<0.001), patient-clinician communication (r=0.50, p<0.001), social influence (r=0.54, p<0.001), and willingness to share (r=0.52, p<0.001). User interface design guidelines were proposed and validated regarding perceived usefulness, health information understandability, personalization, and patient-clinician communication. Future work can involve larger-scale studies testing more tailored design features to compensate for the evolving technology expectations of healthcare consumers
A Multi-Scale Observational Analysis of Factors Leading to Hurricane Earl's Rapid Intensification
No full textHurricane intensification can be broadly related to three physical processes: 1) large-scale environmental influences, 2) mesoscale internal dynamics, and 3) convective scale interactions. These processes may act individually or collectively and all three may be important at different times in a storm's lifecycle. Hurricane Earl 2010 had near-continuous flight coverage observing multiple convective bursts prior to and during the period of rapid intensification. The storm was very energetic and electrified with lightning present in both the eyewall and outer rainbands during the strong convective bursts, which helped in assessing convective vigor. Important environmental conditions that were favorable for intensification of Earl involved weak vertical wind shear, steady warm SSTs, and high OHC. Analysis focuses on the internal storm relationships such as (1) long-lived, intense clusters of convection, (2) associated lightning activity and (3) the establishment of the storm's warm core in the middle and upper troposphere.Includes 1 .wmv video file
THE RELATION BETWEEN SELF-EFFICACY AND BEHAVIORAL PROCESSES OF CHANGE AND THEIR IMPACT ON DRINKING OUTCOMES AFTER ALCOHOL TREATMENT
No full textThe predictive power of alcohol abstinence self-efficacy on drinking outcomes has been widely studied, yet important questions remain about the nature and conditions of its impact. The present study evaluated whether the effect of alcohol abstinence self-efficacy measured at the end of an alcohol treatment program was moderated by reported utilization of behavioral processes of change. It was hypothesized that self-efficacy would be differentially important in predicting quantity and frequency of drinking post-treatment depending upon level of behavioral processes used, such that the relation between self-efficacy and outcomes would be stronger for individuals who reported low levels of processes. Data were analyzed from Project MATCH, a large, multisite alcohol treatment study. A significant curvilinear relation between end-of-treatment self-efficacy and 6- and 12-month post-treatment drinking outcomes was found, and as hypothesized, this relation was moderated by level of behavioral processes of change. Self-efficacy had a stronger impact on quantity and frequency of post-treatment drinking when low levels of behavioral processes were reported than when high levels were used. Individual behavioral processes were also examined, and the moderated relation was strongest for processes related to managing cues, reinforcements, and conditioned responses. These findings have importance treatment implications and highlight the complex nature of self-efficacy's impact on drinking outcomes
Digital Forensics for Infrastructure-as-a-Service Cloud Computing
No full textWe identify important issues in the application of digital forensics to Infrastructure-as-a-Service cloud computing and develop new practical forensic tools and techniques to facilitate forensic exams of the cloud. When investigating suspected cases involving cloud computing, forensic examiners have been poorly equipped to deal with the technical and legal challenges. Because data in the cloud are remote, distributed, and elastic, these challenges include understanding the cloud environment, acquiring and analyzing data remotely, and applying the law to a new domain. Today digital forensics for cloud computing is challenging at best, but can be performed in a manner consistent with federal law using the tools and techniques we developed. The first problem is understanding how and why criminal and civil actions in and against cloud computing are unique and difficult to prosecute. We analyze a digital forensic investigation of crime in the cloud, and present two hypothetical case studies that illustrate the unique challenges of acquisition, chain of custody, trust, and forensic integrity. Understanding these issues introduces legal challenges which are also important for federal, state, and local law enforcement who will soon be called upon to conduct cloud investigations. The second problem is the lack of practical technical tools to conduct cloud forensics. We examine the capabilities for forensics today, evaluate the use of existing tools including EnCase and FTK, and discuss why these tools are incapable of trustworthy cloud acquisition. We design consumer-driven forensic capabilities for OpenStack, including new features for acquiring trustworthy firewall logs, API logs, and disk images. The third problem is a deficit of legal instruments for seizing cloud-based electronically-stored information. We analyze the application of existing policies and laws to the new domain of cloud computing by analyzing case law and legal opinions about digital evidence discovery, and suggest modifications that would enhance cloud the prosecution of cloud- based crimes. We offer guidance about how to author a search warrant for cloud data, and what pertinent data to request. This dissertation enhances our understanding of technical, trust, and legal issues needed to investigate cloud-based crimes and offers new tools and techniques to facilitate such investigations
MITIGATION OF WIND-INDUCED VIBRATIONS OF BALCONY RAILINGS IN A CONDOMINIUM BUILDING
No full textIt was observed that wind-induced vibrations had created destructive effects on corner balcony railings in an oceanfront condominium building. The vibrations of the railings caused disconnections of welds at the ends of the pickets, and noise was generated, which created discomfort to the residents of the building. This work presents a method to mitigate the wind-induced vibrations and noise of the balcony railings. The noise generation mechanisms were investigated; buffeting and vortex-induced vibration were identified as the two main mechanisms. A finite element (FE) model of a railing was developed using commercial FE software ABAQUS. The FE model was validated by modal testing results and used as a basis for later modifications. Design modifications were made for the railing and simulated using ABAQUS; increasing the stiffness of the railing was proposed as a solution based on the FE simulation results and the constraints imposed. A modified railing was installed on one of the corner balconies according to the solution and tested. The experimental results and on-site monitoring on the modified railing indicate that the noise issue has been resolved, and all of the affected railings were demolished and replaced with the modified railings