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Articles 61 - 90 of 6056

Full-Text Articles in Physical Sciences and Mathematics

Effects Of Reproduction On Senescence In Local Species, Nathan Smith Apr 2024

Effects Of Reproduction On Senescence In Local Species, Nathan Smith

Undergraduate Research Conference at Missouri S&T

Understanding the impact of reproduction on the aging process within species populations remains an ongoing challenge in ecological and evolutionary research. In this study, we aim to clarify the relationship between reproduction and senescence using agent-based modeling using wild species data sets. Our objectives include investigating how variations in reproductive rates influence the lifespan and aging trajectories of individuals within populations, as well as identifying potential mechanisms underlying these effects. We will employ agent-based modeling to simulate populations and explore the dynamics of reproduction and senescence using publicly available datasets of local wild species. By manipulating parameters related to reproductive …

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Ta Theoretical Framework For Comparing Rlhf Method, Matthew Dominicis Apr 2024

Ta Theoretical Framework For Comparing Rlhf Method, Matthew Dominicis

Undergraduate Research Conference at Missouri S&T

Reinforcement Learning from Human Feedback (RLHF) can be used as a means to align Al agents and Large Language Models (LLM) to better represent human expectations. There is a myriad of RLHF methods that exist, however it is difficult to benchmark and compare such methods in terms of alignment, training cost, data collection cost, and other metrics. This project aims to create a robust classification for different RLHF methods from a theoretical point of view. Additionally, this project will attempt to propose bounds for the degree of influence on LLMs that stems from human feedback. Open source LLMs will be …

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Simulating Inter-Species Competition In C. Elegans, Kevin Lai Apr 2024

Simulating Inter-Species Competition In C. Elegans, Kevin Lai

Undergraduate Research Conference at Missouri S&T

In biological research, understanding the life cycles of Caenorhabditis elegans (C. elegans) is pivotal for insights into developmental biology, genetics, and population dynamics. Our project builds on Worm-Pop, a Python-based multi-agent simulation of Caenorhabditis elegans (C. elegans) , to enhance its capabilities in simulating survival strategies, reproductive success, and genetic drift. The current model simulates a uniform population without inter-agent interactions. I plan to introduce multiple species of worms into the simulation to study competitive dynamics and determine which variants are most successful under various conditions. Pheromones significantly influence C. elegans behavior, affecting mating, foraging, and social interactions. To address …

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Iron Doped Zeolitic Materials For Propane Dehydrogenation Catalyst, Emily Cahill, Amitava Choudhury Apr 2024

Iron Doped Zeolitic Materials For Propane Dehydrogenation Catalyst, Emily Cahill, Amitava Choudhury

Undergraduate Research Conference at Missouri S&T

This research describes the synthesis of iron-doped zeolitic catalysts for the transformation of propane to propylene. The goal of this research is to develop a dehydrogenation catalyst to convert shale-gas derived cheap propane feedstock to economically valuable propylene, while at the same time making this catalyst sustainable and non-toxic to the environment. Fedoped zeolitic frameworks have shown promising activity in percentage of conversion and in selectivity. In our study we analyzed zeolites ZSM-5 and AIP0-5. These were chosen because they have differences in pore structure , channel sizes, and connectivity between channels. Most importantly the differences in the chemistry as …

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Cytokinesis And Dbf2, Katharine Gray, Katie Shannon Apr 2024

Cytokinesis And Dbf2, Katharine Gray, Katie Shannon

Undergraduate Research Conference at Missouri S&T

During cell division, the cytoplasm must be divided between the parent and daughter cell. The Mitotic Exit Network (MEN) is a signaling pathway that allows a dividing cell to exit mitosis and complete cytokinesis. Obf2 is a MEN protein kinase in yeast, which provides a simplified model for studying this conserved pathway. By regulating Dbf2s' activity through phosphorylation mutants, its effect on cytokinesis can be studied. Cells were viewed under a microscope, to visualize division errors. Yeast cells that fail to complete cytokinesis will form chains, as the budding daughter cells fail to separate from their parents. Chains of 3 …

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Laser Ablation Pulsing On A Cp-Ftmw, Harrison Hawxby Apr 2024

Laser Ablation Pulsing On A Cp-Ftmw, Harrison Hawxby

Undergraduate Research Conference at Missouri S&T

The goal of this research is to study metal containing molecules in the gas phase for structural determination. In order to do this, a metal rod that is turning on a 12V motor is struck by a Nd:YAG laser. Rotational spectra were recorded on a chirped-pulse Fourier transform microwave spectrometer (CP-FTMW) with laser ablation sourcing. Along the way, maintenance on the setup was required, new code was written to accommodate for new problems, as well as production and parametrization of the gas to optimize signal.

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Effect Of Morphology As A Function Of The K-Index On The Drug Loading And Release Profiles In Polyurea And Poly(Isocyanurate-Urethane) Aerogels, Kamden J. George, Stephen Y. Owusu, Chariklia Sotiriou-Leventis Apr 2024

Effect Of Morphology As A Function Of The K-Index On The Drug Loading And Release Profiles In Polyurea And Poly(Isocyanurate-Urethane) Aerogels, Kamden J. George, Stephen Y. Owusu, Chariklia Sotiriou-Leventis

Undergraduate Research Conference at Missouri S&T

This study explores the potential to predict the drug loading and release profiles of aerogels based on their morphologies: a milestone in drug delivery research which can help save time and cost invested in formulating new aerogel drug carriers and cut-down evaluation of the drug delivery capabilities of aerogels to a few experimental runs. Polyurea (PUA) and poly (isocyanurate-urethane) (PIR-PUR) aerogels were used as model systems while 5-fluorouracil (5-FU) and paracetamol (PM) were used as model drugs. These model systems were chosen because they can be synthesized into different morphologies identified by the so-called K-index (contact angle:porosity). The model drugs …

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Stripe Order, Impurities, And Symmetry Breaking In A 3-Dimensional Model Of A Diluted Frustrated Magnet, James Elverson, Thomas Vojta Apr 2024

Stripe Order, Impurities, And Symmetry Breaking In A 3-Dimensional Model Of A Diluted Frustrated Magnet, James Elverson, Thomas Vojta

Undergraduate Research Conference at Missouri S&T

Many quantum materials feature low-temperature phases that break realspace symmetries in addition to spin or charge symmetries. Examples include stripe phases in cuprate superconductors, nematic phases in iron pnictides, and spin-density waves in magnetic materials. Realistic materials always contain some quenched disorder or randomness. To understand the effect of disorder on phases that break real-space symmetries, we investigate the influence of spinless impurities on a frustrated 3-dimensional J 1-J2 Ising model through Monte Carlo simulations. Spin less impurities generate random field type disorder for the spin-density wave (stripe) phase in this system. Whereas the long-range stripe order is destroyed by …

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Development Of Colpitts Self Oscillator For Measurement Of Magnetic And Superconducting Properties, Jasmine Billingsley Apr 2024

Development Of Colpitts Self Oscillator For Measurement Of Magnetic And Superconducting Properties, Jasmine Billingsley

Undergraduate Research Conference at Missouri S&T

Topological materials can serve as promising platforms for next-generation technology. Magnetism in such systems is often a consequence of emergent quantum phenomena, and the traditional framework is insufficient to fully describe their magnetic properties. In this project, we will perform precision magnetic measurements utilizing the Colpitts self-oscillator to determine the temperature- and field-dependent AC magnetic susceptibility in the topological magnetic materials. The collective knowledge learned from this proposed research would shed light on the understanding of exotic magnetism in topological materials, potentially leading to new physics of magnetism.

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Development Of Colpitts Self Oscillator, Jasmin Billingsley Apr 2024

Development Of Colpitts Self Oscillator, Jasmin Billingsley

Undergraduate Research Conference at Missouri S&T

Topological materials can serve as promising platforms for next-generation technology. Magnetism in such systems is often a consequence of emergent quantum phenomena, and the traditional framework is insufficient to fully describe their magnetic properties. In this project, we will perform precision magnetic measurements utilizing the Colpitts self-oscillator to determine the temperature- and field-dependent AC magnetic susceptibility in the topological magnetic materials. The collective knowledge learned from this proposed research would shed light on the understanding of exotic magnetism in topological materials, potentially leading to new physics of magnetism.

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Advanced Electroanalysis For Electrosynthesis, Monica Brachi, Wassim El Housseini, Kevin Beaver, Rohit Jadhav, Ashwini Dantanarayana, Dylan G. Boucher, Shelley D. Minteer Apr 2024

Advanced Electroanalysis For Electrosynthesis, Monica Brachi, Wassim El Housseini, Kevin Beaver, Rohit Jadhav, Ashwini Dantanarayana, Dylan G. Boucher, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

Electrosynthesis is a Popular, Environmentally Friendly Substitute for Conventional Organic Methods. It Involves using Charge Transfer to Stimulate Chemical Reactions through the Application of a Potential or Current between Two Electrodes. in Addition to Electrode Materials and the Type of Reactor Employed, the Strategies for Controlling Potential and Current Have an Impact on the Yields, Product Distribution, and Reaction Mechanism. in This Review, Recent Advances Related to Electroanalysis Applied in Electrosynthesis Were Discussed. the First Part of This Study Acts as a Guide that Emphasizes the Foundations of Electrosynthesis. These Essentials Include Instrumentation, Electrode Selection, Cell Design, and Electrosynthesis Methodologies. …

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Chiral Recognition Of Chiral (Hetero)Cyclic Derivatives Probed By Tetraaza Macrocyclic Chiral Solvating Agents Via ¹H Nmr Spectroscopy, Yu Wang, Hongmei Zhao, Chunxia Yang, Lixia Fang, Li Zheng, Hehua Lv, Pericles Stavropoulos, Lin Ai, Jiaxin Zhang Apr 2024

Chiral Recognition Of Chiral (Hetero)Cyclic Derivatives Probed By Tetraaza Macrocyclic Chiral Solvating Agents Via ¹H Nmr Spectroscopy, Yu Wang, Hongmei Zhao, Chunxia Yang, Lixia Fang, Li Zheng, Hehua Lv, Pericles Stavropoulos, Lin Ai, Jiaxin Zhang

Chemistry Faculty Research & Creative Works

In the Field of Chiral Recognition, Chiral Cyclic Organic Compounds, Especially Heterocyclic Organic Compounds, Have Attracted Little Attention and Have Been Rarely Studied as Chiral Substrates by Means of 1H NMR Spectroscopy. in This Paper, Enantiomers of Thiohydantoin Derivatives, Representing Typical Five-Membered N,N-Heterocycles, Have Been Synthesized and Utilized for Assignment of Absolute Configuration and Analysis of Enantiomeric Excess. All Enantiomers Have Been Successfully Differentiated with the Assistance of Novel Tetraaza Macrocyclic Chiral Solvating Agents (TAMCSAs) by 1H NMR Spectroscopy. Surprisingly, Unprecedented Nonequivalent Chemical Shift Values (Up to 2.052 Ppm) of the NH Proton of Substrates Have Been Observed, a New …

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Structure, Dynamics, And Redox Reactivity Of An All-Purpose Flavodoxin, Sharique Khan, Ahmadullah Ansari, Monica Brachi, Debarati Das, Wassim El Housseini, Shelley Minteer, Anne Frances Miller Apr 2024

Structure, Dynamics, And Redox Reactivity Of An All-Purpose Flavodoxin, Sharique Khan, Ahmadullah Ansari, Monica Brachi, Debarati Das, Wassim El Housseini, Shelley Minteer, Anne Frances Miller

Chemistry Faculty Research & Creative Works

The Flavodoxin Of Rhodopseudomonas Palustris CGA009 (Rp9Fld) Supplies Highly Reducing Equivalents To Crucial Enzymes Such As Hydrogenase, Especially When The Organism Is Iron-Restricted. By Acquiring Those Electrons From Photodriven Electron Flow Via The Bifurcating Electron Transfer Flavoprotein, Rp9Fld Provides Solar Power To Vital Metabolic Processes. To Understand Rp9Fld's Ability To Work With Diverse Partners, We Solved Its Crystal Structure. We Observed The Canonical Flavodoxin (Fld) Fold And Features Common To Other Long-Chain Flds But Not All The Surface Loops Thought To Recognize Partner Proteins. Moreover, Some Of The Loops Display Alternative Structures And Dynamics. To Advance Studies Of Protein–protein Associations …

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Convolutional Spiking Neural Networks For Intent Detection Based On Anticipatory Brain Potentials Using Electroencephalogram, Nathan Lutes, V. Sriram Siddhardh Nadendla, K. Krishnamurthy Apr 2024

Convolutional Spiking Neural Networks For Intent Detection Based On Anticipatory Brain Potentials Using Electroencephalogram, Nathan Lutes, V. Sriram Siddhardh Nadendla, K. Krishnamurthy

Computer Science Faculty Research & Creative Works

Spiking neural networks (SNNs) are receiving increased attention because they mimic synaptic connections in biological systems and produce spike trains, which can be approximated by binary values for computational efficiency. Recently, the addition of convolutional layers to combine the feature extraction power of convolutional networks with the computational efficiency of SNNs has been introduced. This paper studies the feasibility of using a convolutional spiking neural network (CSNN) to detect anticipatory slow cortical potentials (SCPs) related to braking intention in human participants using an electroencephalogram (EEG). Data was collected during an experiment wherein participants operated a remote-controlled vehicle on a testbed …

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Physical And Chemical Methods To Assess Performance Of Tpo-Modified Asphalt Binder, Rebecca M. Herndon, Jay Balasubramanian, Klaus Woelk, Magdy Abdelrahman Apr 2024

Physical And Chemical Methods To Assess Performance Of Tpo-Modified Asphalt Binder, Rebecca M. Herndon, Jay Balasubramanian, Klaus Woelk, Magdy Abdelrahman

Chemistry Faculty Research & Creative Works

The Demand for Effective Asphalt Additives is Growing as Road Infrastructure Ages and More Sustainable Pavement Solutions Are Needed. Tire Pyrolysis Oil (TPO) is an Example Material that Has Been Gaining Attention as a Potential Asphalt Additive. While Physical Performance Grade (PG) Temperatures Are the Predominant Performance Requirements for Asphalt Binders, Chemical Properties Are Also Significant in the Evaluation of Asphalt Performance. There is a Need to Chemically Characterize the Aging of Asphalt Binders Modified with TPO and Link Chemical Changes in Binder Components to Binder Performance. This Study Compares 2%, 4%, and 8% TPO and Asphalt Binder Blends Via …

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Variable-Order Fractional Laplacian And Its Accurate And Efficient Computations With Meshfree Methods, Yixuan Wu, Yanzhi Zhang Apr 2024

Variable-Order Fractional Laplacian And Its Accurate And Efficient Computations With Meshfree Methods, Yixuan Wu, Yanzhi Zhang

Mathematics and Statistics Faculty Research & Creative Works

The variable-order fractional Laplacian plays an important role in the study of heterogeneous systems. In this paper, we propose the first numerical methods for the variable-order Laplacian (-Δ) α (x) / 2 with 0 < α (x) ≤ 2, which will also be referred as the variable-order fractional Laplacian if α(x) is strictly less than 2. We present a class of hypergeometric functions whose variable-order Laplacian can be analytically expressed. Building on these analytical results, we design the meshfree methods based on globally supported radial basis functions (RBFs), including Gaussian, generalized inverse multiquadric, and Bessel-type RBFs, to approximate the variable-order Laplacian (-Δ) α (x) / 2. Our meshfree methods integrate the advantages of both pseudo-differential and hypersingular integral forms of the variable-order fractional Laplacian, and thus avoid numerically approximating the hypersingular integral. Moreover, our methods are simple and flexible of domain geometry, and their computer implementation remains the same for any dimension d ≥ 1. Compared to finite difference methods, our methods can achieve a desired accuracy with much fewer points. This fact makes our method much attractive for problems involving variable-order fractional Laplacian where the number of points required is a critical cost. We then apply our method to study solution behaviors of variable-order fractional PDEs arising in different fields, including transition of waves between classical and fractional media, and coexistence of anomalous and normal diffusion in both diffusion equation and the Allen–Cahn equation. These results would provide insights for further understanding and applications of variable-order fractional derivatives.

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The Dynamics Of The Flavin, Nadph, And Active Site Loops Determine The Mechanism Of Activation Of Class B Flavin-Dependent Monooxygenases, Gustavo Pierdominici-Sottile, Juliana Palma, María Leticia Ferrelli, Pablo Sobrado Apr 2024

The Dynamics Of The Flavin, Nadph, And Active Site Loops Determine The Mechanism Of Activation Of Class B Flavin-Dependent Monooxygenases, Gustavo Pierdominici-Sottile, Juliana Palma, María Leticia Ferrelli, Pablo Sobrado

Chemistry Faculty Research & Creative Works

Flavin-dependent monooxygenases (FMOs) constitute a diverse enzyme family that catalyzes crucial hydroxylation, epoxidation, and Baeyer–Villiger reactions across various metabolic pathways in all domains of life. Due to the intricate nature of this enzyme family's mechanisms, some aspects of their functioning remain unknown. Here, we present the results of molecular dynamics computations, supplemented by a bioinformatics analysis, that clarify the early stages of their catalytic cycle. We have elucidated the intricate binding mechanism of NADPH and L-Orn to a class B monooxygenase, the ornithine hydroxylase from (Formula presented.) (Formula presented.) known as SidA. Our investigation involved a comprehensive characterization of the …

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Cr-Sam: Curvature Regularized Sharpness-Aware Minimization, Tao Wu, Tony Tie Luo, Donald C. Wunsch Mar 2024

Cr-Sam: Curvature Regularized Sharpness-Aware Minimization, Tao Wu, Tony Tie Luo, Donald C. Wunsch

Computer Science Faculty Research & Creative Works

The Capacity to Generalize to Future Unseen Data Stands as One of the Utmost Crucial Attributes of Deep Neural Networks. Sharpness-Aware Minimization (SAM) Aims to Enhance the Generalizability by Minimizing Worst-Case Loss using One-Step Gradient Ascent as an Approximation. However, as Training Progresses, the Non-Linearity of the Loss Landscape Increases, Rendering One-Step Gradient Ascent Less Effective. on the Other Hand, Multi-Step Gradient Ascent Will Incur Higher Training Cost. in This Paper, We Introduce a Normalized Hessian Trace to Accurately Measure the Curvature of Loss Landscape on Both Training and Test Sets. in Particular, to Counter Excessive Non-Linearity of Loss Landscape, …

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Lrs: Enhancing Adversarial Transferability Through Lipschitz Regularized Surrogate, Tao Wu, Tony Tie Luo, Donald C. Wunsch Mar 2024

Lrs: Enhancing Adversarial Transferability Through Lipschitz Regularized Surrogate, Tao Wu, Tony Tie Luo, Donald C. Wunsch

Computer Science Faculty Research & Creative Works

The Transferability of Adversarial Examples is of Central Importance to Transfer-Based Black-Box Adversarial Attacks. Previous Works for Generating Transferable Adversarial Examples Focus on Attacking Given Pretrained Surrogate Models While the Connections between Surrogate Models and Adversarial Trasferability Have Been overlooked. in This Paper, We Propose Lipschitz Regularized Surrogate (LRS) for Transfer-Based Black-Box Attacks, a Novel Approach that Transforms Surrogate Models towards Favorable Adversarial Transferability. using Such Transformed Surrogate Models, Any Existing Transfer-Based Black-Box Attack Can Run Without Any Change, Yet Achieving Much Better Performance. Specifically, We Impose Lipschitz Regularization on the Loss Landscape of Surrogate Models to Enable a Smoother …

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Nitrene-Transfer Chemistry To C-H And C═C Bonds Mediated By Triangular Coinage Metal Platforms Supported By Triply Bridging Pnictogen Elements Sb(Iii) And Bi(Iii), Meenakshi Sharma, Reece M. Fritz, Joseph O. Adebanjo, Zhou Lu, Thomas R. Cundari, Mohammad A. Omary, Amitava Choudhury, Pericles Stavropoulos Mar 2024

Nitrene-Transfer Chemistry To C-H And C═C Bonds Mediated By Triangular Coinage Metal Platforms Supported By Triply Bridging Pnictogen Elements Sb(Iii) And Bi(Iii), Meenakshi Sharma, Reece M. Fritz, Joseph O. Adebanjo, Zhou Lu, Thomas R. Cundari, Mohammad A. Omary, Amitava Choudhury, Pericles Stavropoulos

Chemistry Faculty Research & Creative Works

Tripodal Ligands (TMG3trphen-E) That Feature Heavy Pnictogen Elements (E = Sb(III), Bi(III)) And Tetramethylguanidinyl (TMG) Arms Have Been Explored In Stabilizing Cu(I) And Ag(I) Sites And Facilitating Nitrene-Transfer Chemistry. Compounds [(TMG3trphen-E)M3(Μ-X)3] (M = Cu(I), Ag(I); X = Cl, Br, I) Have Been Generated Upon Extraction Of M3(Μ-X)3 Units From MX Sources, Exhibiting Support Of The Crown-Shaped M3(Μ-X)3 Fragment By M-NTMG Bonds And Triply Bridging E → M3 Interactions. Orbital Interactions Between Cu(I) Sites And NTMG Residues Are More Dominant Than Sb/Bi → Cu3 Donor Interactions Between The Sb 5s Or Bi 6s Orbitals And Admixed Cu 4s/3d Orbitals, With Larger …

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Second Inflection Point Of Supercooled Water Surface Tension Induced By Hydrogen Bonds: A Molecular-Dynamics Study, Fawaz Hrahsheh, Inshad Jum'h, Gerald Wilemski Mar 2024

Second Inflection Point Of Supercooled Water Surface Tension Induced By Hydrogen Bonds: A Molecular-Dynamics Study, Fawaz Hrahsheh, Inshad Jum'h, Gerald Wilemski

Physics Faculty Research & Creative Works

Surface Tension Of Supercooled Water Is A Fundamental Property In Various Scientific Processes. In This Study, We Perform Molecular Dynamics Simulations With The TIP4P-2005 Model To Investigate The Surface Tension Of Supercooled Water Down To 220 K. Our Results Show A Second Inflection Point (SIP) In The Surface Tension At Temperature TSIP ≈ 267.5 ± 2.3 K. Using An Extended IAPWS-E Functional Fit For The Water Surface Tension, We Calculate The Surface Excess Internal-Energy And Entropy Terms Of The Excess Helmholtz Free Energy. Similar To Prior Studies [Wang Et Al., Phys. Chem. Chem. Phys. 21, 3360 (2019); Gorfer Et Al., …

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Highly Efficient Dopamine Sensing With A Carbon Nanotube-Encapsulated Metal Chalcogenide Nanostructure, Harish Singh, Jiandong Wu, Kurt A.L. Lagemann, Manashi Nath Mar 2024

Highly Efficient Dopamine Sensing With A Carbon Nanotube-Encapsulated Metal Chalcogenide Nanostructure, Harish Singh, Jiandong Wu, Kurt A.L. Lagemann, Manashi Nath

Chemical and Biochemical Engineering Faculty Research & Creative Works

Carbon nanotube-encapsulated nickel selenide composite nanostructures were used as nonenzymatic electrochemical sensors for dopamine detection. These composite nanostructures were synthesized through a simple, one-step, and environmentally friendly chemical vapor deposition method, wherein the CNTs were formed in situ from pyrolysis of a carbon-rich metallo-organic precursor. The composition and morphology of these hybrid NiSe2-filled carbon nanostructures were confirmed by powder X-ray diffraction, Raman, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy images. Electrochemical tests demonstrated that the as-synthesized hybrid nanostructures exhibited outstanding electrocatalytic performance toward dopamine oxidation, with a high sensitivity of 19.62 μA μM-1 cm-2, low detection limit, broad linear …

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Ionization Cross Sections Of Hydrogen Molecule By Electron And Positron Impact, Károly Tőkési, Robert D. Dubois Mar 2024

Ionization Cross Sections Of Hydrogen Molecule By Electron And Positron Impact, Károly Tőkési, Robert D. Dubois

Physics Faculty Research & Creative Works

We Present Ionization Cross Sections of Hydrogen Molecules by Electron and Positron Impact for Impact Energies between 20 and 1000 EV. a Three-Body Classical Trajectory Monte Carlo Approximation is Applied to Mimic the Collision System. in This Approach, the H2 Molecule is Modeled by a Hydrogen-Type Atom with One Active Electron Bound to a Central Core of Effective Charge with an Effective Binding Energy. Although This Model is Crude for Describing a Hydrogen Molecule, We Found that the Total Cross Sections for Positron Impact Agree Reasonably Well with the Experimental Data. for the Electron Impact, Our Calculated Cross Sections Are …

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Analyzing Biomedical Datasets With Symbolic Tree Adaptive Resonance Theory, Sasha Petrenko, Daniel B. Hier, Mary A. Bone, Tayo Obafemi-Ajayi, Erik J. Timpson, William E. Marsh, Michael Speight, Donald C. Wunsch Mar 2024

Analyzing Biomedical Datasets With Symbolic Tree Adaptive Resonance Theory, Sasha Petrenko, Daniel B. Hier, Mary A. Bone, Tayo Obafemi-Ajayi, Erik J. Timpson, William E. Marsh, Michael Speight, Donald C. Wunsch

Chemistry Faculty Research & Creative Works

Biomedical Datasets Distill Many Mechanisms Of Human Diseases, Linking Diseases To Genes And Phenotypes (Signs And Symptoms Of Disease), Genetic Mutations To Altered Protein Structures, And Altered Proteins To Changes In Molecular Functions And Biological Processes. It Is Desirable To Gain New Insights From These Data, Especially With Regard To The Uncovering Of Hierarchical Structures Relating Disease Variants. However, Analysis To This End Has Proven Difficult Due To The Complexity Of The Connections Between Multi-Categorical Symbolic Data. This Article Proposes Symbolic Tree Adaptive Resonance Theory (START), With Additional Supervised, Dual-Vigilance (DV-START), And Distributed Dual-Vigilance (DDV-START) Formulations, For The Clustering Of …

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Continual Online Learning-Based Optimal Tracking Control Of Nonlinear Strict-Feedback Systems: Application To Unmanned Aerial Vehicles, Irfan Ganie, Sarangapani Jagannathan Mar 2024

Continual Online Learning-Based Optimal Tracking Control Of Nonlinear Strict-Feedback Systems: Application To Unmanned Aerial Vehicles, Irfan Ganie, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

A novel optimal trajectory tracking scheme is introduced for nonlinear continuous-time systems in strict feedback form with uncertain dynamics by using neural networks (NNs). The method employs an actor-critic-based NN back-stepping technique for minimizing a discounted value function along with an identifier to approximate unknown system dynamics that are expressed in augmented form. Novel online weight update laws for the actor and critic NNs are derived by using both the NN identifier and Hamilton-Jacobi-Bellman residual error. A new continual lifelong learning technique utilizing the Fisher Information Matrix via Hamilton-Jacobi-Bellman residual error is introduced to obtain the significance of weights in …

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Thermal Performance Of Forced Convection Of Water- Nepcm Nanofluid Over A Semi-Cylinder Heat Source, Xiaoming Wang, Rassol H. Rasheed, Babak Keivani, Dheyaa J. Jasim, Abbas J. Sultan, Sajad Hamedi, Hamed Kazemi-Varnamkhasti, Soheil Salahshour, Davood Toghraie Mar 2024

Thermal Performance Of Forced Convection Of Water- Nepcm Nanofluid Over A Semi-Cylinder Heat Source, Xiaoming Wang, Rassol H. Rasheed, Babak Keivani, Dheyaa J. Jasim, Abbas J. Sultan, Sajad Hamedi, Hamed Kazemi-Varnamkhasti, Soheil Salahshour, Davood Toghraie

Mathematics and Statistics Faculty Research & Creative Works

1) Background: Phase change materials (PCMs) have been used statically, which has caused the use of these materials to face challenges. Encapsulating PCMs and combining them with the base fluid can significantly solve the problem of using PCMs in BTM systems. In the present study, based on computational fluid dynamics, forced convection heat transfer of nano-encapsulated phase change materials (NEPCM) in a BTM system are simulated. The main aim of the present research is to reduce the temperature at the surface of the hot cylinder. 2) Methods: In this research, we simulated lithium battery thermal management systems in both steady …

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Universality Class Of A Spinor Bose–Einstein Condensate Far From Equilibrium, Seung Jung Huh, Koushik Mukherjee, Kiryang Kwon, Jihoon Seo, Junhyeok Hur, Simeon I. Mistakidis, H. R. Sadeghpour, Jae Yoon Choi Mar 2024

Universality Class Of A Spinor Bose–Einstein Condensate Far From Equilibrium, Seung Jung Huh, Koushik Mukherjee, Kiryang Kwon, Jihoon Seo, Junhyeok Hur, Simeon I. Mistakidis, H. R. Sadeghpour, Jae Yoon Choi

Physics Faculty Research & Creative Works

Scale Invariance And Self-Similarity In Physics Provide A Unified Framework For Classifying Phases Of Matter And Dynamical Properties Near Equilibrium In Both Classical And Quantum Systems. This Paradigm Has Been Further Extended To Isolated Many-Body Quantum Systems Driven Far From Equilibrium, For Which The Physical Observables Exhibit Dynamical Scaling With Universal Scaling Exponents. Universal Dynamics Appear In A Wide Range Of Scenarios, Including Cosmology, Quark–gluon Matter, Ultracold Atoms And Quantum Spin Magnets. However, How The Universal Dynamics Depend On The Symmetry Of The Underlying Hamiltonian In Non-Equilibrium Systems Remains An Outstanding Challenge. Here We Report On The Classification Of Universal …

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Electrocatalytic Asymmetric Nozaki-Hiyama-Kishi Decarboxylative Coupling: Scope, Applications, And Mechanism, Yang Gao, Baiyang Jiang, Nathan C. Friede, Arianne C. Hunter, Dylan G. Boucher, Shelley D. Minteer, Matthew S. Sigman, Sarah E. Reisman, Phil S. Baran Feb 2024

Electrocatalytic Asymmetric Nozaki-Hiyama-Kishi Decarboxylative Coupling: Scope, Applications, And Mechanism, Yang Gao, Baiyang Jiang, Nathan C. Friede, Arianne C. Hunter, Dylan G. Boucher, Shelley D. Minteer, Matthew S. Sigman, Sarah E. Reisman, Phil S. Baran

Chemistry Faculty Research & Creative Works

The first general enantioselective alkyl-Nozaki-Hiyama-Kishi (NHK) coupling reactions are disclosed herein by employing a Cr-electrocatalytic decarboxylative approach. Using easily accessible aliphatic carboxylic acids (via redox-active esters) as alkyl nucleophile synthons, in combination with aldehydes and enabling additives, chiral secondary alcohols are produced in a good yield with high enantioselectivity under mild reductive electrolysis. This reaction, which cannot be mimicked using stoichiometric metal or organic reductants, tolerates a broad range of functional groups and is successfully applied to dramatically simplify the synthesis of multiple medicinally relevant structures and natural products. Mechanistic studies revealed that this asymmetric alkyl e-NHK reaction was enabled …

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Papain-Catalyzed Synthesis Of Oligolysine In Low-Water Organic Reaction Media, Lakshmi Priya Ravikrishna, Krishnamurthi Tamilarasan, Vairamani Mariappanadar, Shubhender Kapila, Mathur Rajesh Feb 2024

Papain-Catalyzed Synthesis Of Oligolysine In Low-Water Organic Reaction Media, Lakshmi Priya Ravikrishna, Krishnamurthi Tamilarasan, Vairamani Mariappanadar, Shubhender Kapila, Mathur Rajesh

Chemistry Faculty Research & Creative Works

Oligopeptides of l-lysine have the potential for applications in various scientific and technical areas. The number of residues in polycationic compounds such as oligolysine is also reported to have an effect on its biological properties. Hence, there is a necessity for developing efficient oligolysine synthesis methods where the oligopeptide dispersity can be tailored, along with optimum yield values. The ability of proteases to reverse their proteolytic activity to synthesize peptides has been reported in the literature. However, protease-catalyzed synthesis of oligopeptides of basic amino acids such as lysine in aqueous buffers is hindered by unfavorable thermodynamics. In this work, a …

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Energy And Angular Distributions In 250 Ev Electron And Positron Collisions With Argon Atom, K. Tőkési, Robert D. Dubois Feb 2024

Energy And Angular Distributions In 250 Ev Electron And Positron Collisions With Argon Atom, K. Tőkési, Robert D. Dubois

Physics Faculty Research & Creative Works

We present energy and angular differential cross sections for single ionization in collisions between electrons and positrons with argon atoms at 250 eV. We treat the collision classically using the three-body approximation where the target atoms are described within the single active electron approximation using a Garvey model potential and only the outermost electron is involved in the collision dynamics. Our present classical trajectory Monte Carlo model is shown to describe the ionization cross sections reasonably well and agree with existing experimental data. We show that the energy distributions, both for electron and positron impact, have the same shape and …

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