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Is Performance Fairness Achievable In Presence Of Attackers Under Federated Learning?, Ashish Gupta, George Markowsky, Sajal K. Das Sep 2023

Is Performance Fairness Achievable In Presence Of Attackers Under Federated Learning?, Ashish Gupta, George Markowsky, Sajal K. Das

Computer Science Faculty Research & Creative Works

In the last few years, Federated Learning (FL) has received extensive attention from the research community because of its capability for privacy-preserving, collaborative learning from heterogeneous data sources. Most FL studies focus on either average performance improvement or the robustness to attacks, while some attempt to solve both jointly. However, the performance disparities across clients in the presence of attackers have largely been unexplored. In this work, we propose a novel Fair Federated Learning scheme with Attacker Detection capability (abbreviated as FFL+AD) to minimize performance discrepancies across benign participants. FFL+AD enables the server to identify attackers and learn their malign …

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Is Performance Fairness Achievable In Presence Of Attackers Under Federated Learning?, Ashish Gupta, George Markowsky, Sajal K. Das Sep 2023

Is Performance Fairness Achievable In Presence Of Attackers Under Federated Learning?, Ashish Gupta, George Markowsky, Sajal K. Das

Computer Science Faculty Research & Creative Works

In the last few years, Federated Learning (FL) has received extensive attention from the research community because of its capability for privacy-preserving, collaborative learning from heterogeneous data sources. Most FL studies focus on either average performance improvement or the robustness to attacks, while some attempt to solve both jointly. However, the performance disparities across clients in the presence of attackers have largely been unexplored. in this work, we propose a novel Fair Federated Learning scheme with Attacker Detection capability (abbreviated as FFL+AD) to minimize performance discrepancies across benign participants. FFL+AD enables the server to identify attackers and learn their malign …

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Ambient Processed Rgo/Ti3cntx Mxene Thin Film With High Oxidation Stability, Photosensitivity, And Self-Cleaning Potential, Muhammad Abiyyu Kenichi Purbayanto, Dominika Bury, Madhurya Chandel, Zhila Dehghan Shahrak, Vadym Mochalin, Anna Wójcik, Dorota Moszczyńska, Anita Wojciechowska, Anika Tabassum, Michael Naguib, Agnieszka Maria Jastrzębska Sep 2023

Ambient Processed Rgo/Ti3cntx Mxene Thin Film With High Oxidation Stability, Photosensitivity, And Self-Cleaning Potential, Muhammad Abiyyu Kenichi Purbayanto, Dominika Bury, Madhurya Chandel, Zhila Dehghan Shahrak, Vadym Mochalin, Anna Wójcik, Dorota Moszczyńska, Anita Wojciechowska, Anika Tabassum, Michael Naguib, Agnieszka Maria Jastrzębska

Chemistry Faculty Research & Creative Works

Solution-Based Processing Offers Advantages for Producing Thin Films Due to Scalability, Low Cost, Simplicity, and Benignity to the Environment. Here, We Develop Conductive and Photoactivated Self-Cleaning Reduced Graphene Oxide (RGO)/Ti3CNTx MXene Thin Films Via Spin Coating under Ambient Conditions. the Addition of a Thin RGO Layer on Top of Ti3CNTx Resulted in Up to 45-Fold Improvement in the Environmental Stability of the Film Compared to the Bare Ti3CNTx Film. the Optimized RGO/Ti3CNTx Thin Film Exhibits an Optical Transmittance of 74% in the Visible Region of the Spectrum and …

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Phenyl Acrylate-Based Cross-Linked Anion Exchange Membranes For Non-Aqueous Redox Flow Batteries, Md Motiur R. Mazumder, Rohit G. Jadhav, Shelley D. Minteer Sep 2023

Phenyl Acrylate-Based Cross-Linked Anion Exchange Membranes For Non-Aqueous Redox Flow Batteries, Md Motiur R. Mazumder, Rohit G. Jadhav, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

Redox flow batteries (RFBs) are of recent interest to store harvested renewable energy for improving grid reliability and utilization. in this study, we synthesized and characterized a series of phenyl acrylate-Based UV-cross-linked anion exchange membranes (AEMs) and explored the performance of these AEMs in a model non-aqueous RFB under model conditions. Infrared spectroscopy was utilized to confirm the incorporation of ion carriers in the phenyl acrylate backbone. the electrochemical performance was compared with the commercial Fumasep membrane Fuma-375 based on high stability in non-aqueous solvents, high permeability to the charge-carrying ion, low resistance, low crossover of the redox-active molecules, and …

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Chitosan-Coated Lignin Nanoparticles Enhance Adsorption And Proliferation Of Alcanivorax Borkumensis At The Hexadecane-Water Interface, Amber J. Pete, Jin Gyun Lee, Michael G. Benton, Bhuvnesh Bharti Sep 2023

Chitosan-Coated Lignin Nanoparticles Enhance Adsorption And Proliferation Of Alcanivorax Borkumensis At The Hexadecane-Water Interface, Amber J. Pete, Jin Gyun Lee, Michael G. Benton, Bhuvnesh Bharti

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bioremediation of oil spills occurs when indigenous microbes metabolize petroleum hydrocarbons. Rapid proliferation of hydrocarbon-consuming bacteria near the oil-water interface is vital to optimizing the oil biodegradation rate. Adding nanoparticles (NPs) to microbial systems can enhance the bacterial growth rate. However, the role of NP source material and surface charge on their ability to impact bacterial growth and oil-water interface characteristics is poorly understood. Here, we investigate the role of NP composition and surface chemistry on the growth rate of hydrocarbon-consuming bacteria and its attachment to the oil-water interface. We use Alcanivorax borkumensis as a model organism because of its …

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Mechanistic Insights Into Electrocatalytic Carbon−Bromine Bond Cleavage In Polybrominated Phenols, Eric C.R. Mckenzie, Seyyedamirhossein Hosseini, Mayank Tanwar, Matthew Neurock, Shelley D. Minteer, Stephen C. Jacobson Sep 2023

Mechanistic Insights Into Electrocatalytic Carbon−Bromine Bond Cleavage In Polybrominated Phenols, Eric C.R. Mckenzie, Seyyedamirhossein Hosseini, Mayank Tanwar, Matthew Neurock, Shelley D. Minteer, Stephen C. Jacobson

Chemistry Faculty Research & Creative Works

Carbon−halogen bond cleavage has been studied extensively for many years as a simple electrosynthesis step in the formation of more complex natural products. Reduction of halogenated phenols has received less attention, in part, due to the lowered faradaic efficiency resulting from the competing hydrogen evolution reaction. Herein, we report the electroreduction of a series of brominated phenols through a homogeneous electrocatalytic (EC′) mechanism. Beginning with the structurally simple 2-bromophenol, we use foot-of-the-wave analysis to determine optimal catalysts. Nickel (II) salen requires the lowest overpotential for C−Br reduction and was used across all substrates. Chronoamperometric studies and density functional theory calculations …

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Introduction To 'Artificial Intelligence In Failure Analysis Of Transportation Infrastructure And Materials', Yue Hou, Qiao Dong, Dawei Wang, Jenny Liu Sep 2023

Introduction To 'Artificial Intelligence In Failure Analysis Of Transportation Infrastructure And Materials', Yue Hou, Qiao Dong, Dawei Wang, Jenny Liu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Transportation infrastructures, including roads, bridges, tunnels, stations, airports and subways, play fundamental roles in modern society. Engineering failures of transportation infrastructures may result in significant damage to the public. The traditional methods are to monitor, store and analyze the information during the infrastructure and material design, testing, construction, numerical simulations, evaluation, operation, maintenance and preservation, using mechanistic-based, material based and statistics-based approaches. In recent decades, artificial intelligence (AI) has drawn the attention of many researchers and has been used as a powerful tool to understand and analyze the engineering failures in transportation infrastructure and materials. AI has the advantages of …

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Hawc Study Of The Very-High-Energy Γ-Ray Spectrum Of Hawc J1844−034, A. Albert, C. Alvarez, D. Avila Rojas, H. A.Ayala Solares, R. Babu, E. Belmont-Moreno, M. Breuhaus, T. Capistrán, A. Carramiñana, S. Casanova, J. Cotzomi, S. Coutiño De León, E. De La Fuente, D. Depaoli, R. Diaz Hernandez, B. L. Dingus, M. A. Duvernois, M. Durocher, K. Engel, C. Espinoza, K. L. Fan, K. Fang, N. Fraija, J. A. Garcia-Gonzalez, M. M. Gonzalez, J. A. Goodman, S. Groetsch, J. P, Harding, I. Herzog, J. Hinton, D. Huang, F. Hueyotl-Zahuantitla, T. B. Humensky, P. Huntemeyer, V. Joshi, S. Kaufmann, J. Lee, H. Leon Vargas, A. L. Longinotti, G. Luis-Raya, K. Malone, O. Martinez, J. Martinez-Castro, J. A. Matthews, P. Miranda-Romagnoli, J. A. Morales-Soto, E. Moreno, M. Mostafa, L. Nellen, R. Noriega-Papaqui, L. Olivera-Nieto, N. Omodei, E. G. Perez-Perez, C. D. Rho, D. Rosa-Gonzalez, E. Ruiz-Velasco, H. Salazar, D. Salazar-Gallegos, A. Sandoval, M. Schneider, J. Serna-Franco, A. J. Smith, Y. Son, R. W. Springer, O. Tibolla, K. Tollefson, I. Torres, R. Torres-Escobedo, R. Turner, F. Urena-Mena, E. Varela, L. Villasenor, Xiaojie Wang, I. J. Watson, E. Willox, H. Zhou Sep 2023

Hawc Study Of The Very-High-Energy Γ-Ray Spectrum Of Hawc J1844−034, A. Albert, C. Alvarez, D. Avila Rojas, H. A.Ayala Solares, R. Babu, E. Belmont-Moreno, M. Breuhaus, T. Capistrán, A. Carramiñana, S. Casanova, J. Cotzomi, S. Coutiño De León, E. De La Fuente, D. Depaoli, R. Diaz Hernandez, B. L. Dingus, M. A. Duvernois, M. Durocher, K. Engel, C. Espinoza, K. L. Fan, K. Fang, N. Fraija, J. A. Garcia-Gonzalez, M. M. Gonzalez, J. A. Goodman, S. Groetsch, J. P, Harding, I. Herzog, J. Hinton, D. Huang, F. Hueyotl-Zahuantitla, T. B. Humensky, P. Huntemeyer, V. Joshi, S. Kaufmann, J. Lee, H. Leon Vargas, A. L. Longinotti, G. Luis-Raya, K. Malone, O. Martinez, J. Martinez-Castro, J. A. Matthews, P. Miranda-Romagnoli, J. A. Morales-Soto, E. Moreno, M. Mostafa, L. Nellen, R. Noriega-Papaqui, L. Olivera-Nieto, N. Omodei, E. G. Perez-Perez, C. D. Rho, D. Rosa-Gonzalez, E. Ruiz-Velasco, H. Salazar, D. Salazar-Gallegos, A. Sandoval, M. Schneider, J. Serna-Franco, A. J. Smith, Y. Son, R. W. Springer, O. Tibolla, K. Tollefson, I. Torres, R. Torres-Escobedo, R. Turner, F. Urena-Mena, E. Varela, L. Villasenor, Xiaojie Wang, I. J. Watson, E. Willox, H. Zhou

Physics Faculty Research & Creative Works

Recently, the region surrounding eHWC J1842−035 has been studied extensively by γ-ray observatories due to its extended emission reaching up to a few hundred TeV and potential as a hadronic accelerator. In this work, we use 1910 days of cumulative data from the High-Altitude Water Cherenkov (HAWC) observatory to carry out a dedicated systematic source search of the eHWC J1842−035 region. During the search, we found three sources in the region, namely, HAWC J1844−034, HAWC J1843−032, and HAWC J1846−025. We have identified HAWC J1844−034 as the extended source that emits photons with energies up to 175 TeV. We compute the …

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Interactions And Dynamics Of One-Dimensional Droplets, Bubbles And Kinks, Garyfallia Katsimiga, Simeon I. Mistakidis, Boris A. Malomed, Dimitris J. Frantzeskakis, Ricardo Carretero-Gonzalez, Panayotis G. Kevrekidis Sep 2023

Interactions And Dynamics Of One-Dimensional Droplets, Bubbles And Kinks, Garyfallia Katsimiga, Simeon I. Mistakidis, Boris A. Malomed, Dimitris J. Frantzeskakis, Ricardo Carretero-Gonzalez, Panayotis G. Kevrekidis

Physics Faculty Research & Creative Works

We Explore The Dynamics And Interactions Of Multiple Bright Droplets And Bubbles, As Well As The Interactions Of Kinks With Droplets And With Antikinks, In The Extended One-Dimensional Gross–Pitaevskii Model Including The Lee–Huang–Yang Correction. Existence Regions Are Identified For The One-Dimensional Droplets And Bubbles In Terms Of Their Chemical Potential, Verifying The Stability Of The Droplets And Exposing The Instability Of The Bubbles. The Limiting Case Of The Droplet Family Is A Stable Kink. The Interactions Between Droplets Demonstrate In-Phase (Out-Of-Phase) Attraction (Repulsion), With The So-Called Manton's Method Explicating The Observed Dynamical Response, And Mixed Behavior For Intermediate Values Of …

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Qc-Sane: Robust Control In Drl Using Quantile Critic With Spiking Actor And Normalized Ensemble, Surbhi Gupta, Gaurav Singal, Deepak Garg, Sarangapani Jagannathan Sep 2023

Qc-Sane: Robust Control In Drl Using Quantile Critic With Spiking Actor And Normalized Ensemble, Surbhi Gupta, Gaurav Singal, Deepak Garg, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

Recently Introduced Deep Reinforcement Learning (DRL) Techniques in Discrete-Time Have Resulted in Significant Advances in Online Games, Robotics, and So On. Inspired from Recent Developments, We Have Proposed an Approach Referred to as Quantile Critic with Spiking Actor and Normalized Ensemble (QC-SANE) for Continuous Control Problems, Which Uses Quantile Loss to Train Critic and a Spiking Neural Network (NN) to Train an Ensemble of Actors. the NN Does an Internal Normalization using a Scaled Exponential Linear Unit (SELU) Activation Function and Ensures Robustness. the Empirical Study on Multijoint Dynamics with Contact (MuJoCo)-Based Environments Shows Improved Training and Test Results Than …

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Data-Driven Analysis Of Construction Bidding Stage-Related Causes Of Disputes, Muaz O. Ahmed, Islam H. El-Adaway Sep 2023

Data-Driven Analysis Of Construction Bidding Stage-Related Causes Of Disputes, Muaz O. Ahmed, Islam H. El-Adaway

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Construction bidding is a complex process that involves several potential risks and uncertainties for all the stakeholders involved. Such complexities, risks, and uncertainties, if uncontrolled, can lead to the rise of claims, conflicts, and disputes during the course of a project. Even though a substantial amount of knowledge has been acquired about construction disputes and their causation, there is a lack of research that examines the causes of disputes associated with the bidding phase of projects. This study addresses this knowledge gap within the context of infrastructure projects. In investigating and analyzing the causation of disputes related to the bidding …

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Reproducibly Defining Electrode Area Of Carbon Paper Electrodes Via Machine Cutting And High-Throughput Waxing, Rokas Gerulskis, Shelley D. Minteer Sep 2023

Reproducibly Defining Electrode Area Of Carbon Paper Electrodes Via Machine Cutting And High-Throughput Waxing, Rokas Gerulskis, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

Carbon paper is one of the most common carbon electrode materials employed in electrochemical research due to its low cost, disposability, and controllable dimensions and scaling. Carbon paper is usually hand cut, and a variety of strategies are used to define electrode area. This procedure is tedious, imprecise, and inaccurate, yielding coefficients of variation in peak current output as high as 20%. Imprecision in hand-preparation translates directly to poor reproducibility in electrochemical data leading to challenges in directly comparing data across research groups and research fields. This work introduces an inexpensive and precise method to automatically cut and rapidly wax …

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Comparative Efficacy Of Systemic And Combination Fungicides For The Control Of Alternaria Leaf Spot Of Cabbage, Patience U. Ishieze, Chinedu F. Amuji, Kevin I. Ugwuoke, Paul K. Baiyeri, Michael O. Eze Sep 2023

Comparative Efficacy Of Systemic And Combination Fungicides For The Control Of Alternaria Leaf Spot Of Cabbage, Patience U. Ishieze, Chinedu F. Amuji, Kevin I. Ugwuoke, Paul K. Baiyeri, Michael O. Eze

Chemistry Faculty Research & Creative Works

Alternaria leaf spot of cabbage, caused by the Alternaria brassicicola, affects leaves of cabbages and often results in head rots causing severe decline in yield. in this work, the effects of systemic and combination fungicides on A. brassicicola mycelia growth in vitro and disease severity in field trials were investigated. the results of in vitro evaluation revealed that both fungicides significantly inhibited (p < 0.05) the growth of A. brassicicola under in vitro conditions. However, metal Axyl-M 6% was less effective with 100 μg/mL having only 30 ± 3.5% inhibition. on the other hand, 100 μg/mL of mancozeb 63% + carbendazim 12% had 94 ± 3.5% growth inhibition of A. brassicicola, respectively, under the same conditions. Dose-response analysis of the efficacy of the two fungicides showed that the LC50 of metal Axyl-M 6% and mancozeb 63% + carbendazim 12% were 125.52 ppm and 57.22 ppm, respectively, indicating the superiority of combination fungicide over systemic fungicide alone. Field studies showed that while manure type significantly impacted on biomass production (p < 0.001), it did not significantly affect disease severity. on the other hand, the frequency of fungicide application impacted on disease severity, with biweekly application leading to a significant reduction in disease severity after 10 weeks.

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Development Of An Enhanced Hybrid Bi-Catalytic Electrode Containing Bimetallic Composite Catalyst And Immobilized Enzyme For Complete Glucose Electrooxidation, Jefferson Honorio Franco, João Victor Bonaldo, Rodrigo Garcia Da Silva, Shelley D. Minteer, Adalgisa R. De Andrade Sep 2023

Development Of An Enhanced Hybrid Bi-Catalytic Electrode Containing Bimetallic Composite Catalyst And Immobilized Enzyme For Complete Glucose Electrooxidation, Jefferson Honorio Franco, João Victor Bonaldo, Rodrigo Garcia Da Silva, Shelley D. Minteer, Adalgisa R. De Andrade

Chemistry Faculty Research & Creative Works

We describe an enzymatic fuel cell (EFC) that can electrooxidize glucose completely. the EFC contains the hybrid Ni@Pt-CNT/OxOx bioanode, composed of a bimetallic composite catalyst (Ni@Pt-CNT) and the enzyme oxalate oxidase (OxOx), which can cleave carbon-carbon bonds. Ni@Pt-CNT/OxOx displayed 3-fold higher catalytic activity in the presence than in the absence of glucose (1.3 and 0.4 mA cm−2, respectively), indicating that Ni@Pt-CNT and OxOx acted synergistically. Electrochemical impedance spectroscopy showed that Ni@Pt-CNT/OxOx had higher charge transfer resistance and double layer capacitance than Ni@Pt-CNT. Long-term bulk electrolysis (18 h) revealed that the EFC operating with Ni@Pt-CNT/OxOx presented better current density and stability …

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Change Is The Only Constant: A Virtual Issue On Contemporary Catalysis, Shelley Minteer, Stephanie L. Brock, Géraldine Masson, Raymond E. Schaak Aug 2023

Change Is The Only Constant: A Virtual Issue On Contemporary Catalysis, Shelley Minteer, Stephanie L. Brock, Géraldine Masson, Raymond E. Schaak

Chemistry Faculty Research & Creative Works

No abstract provided.

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Unraveling Hydrogen Atom Transfer Mechanisms With Voltammetry: Oxidative Formation And Reactivity Of Cobalt Hydride, Dylan G. Boucher, Andrew D. Pendergast, Xiangyu Wu, Zachary A. Nguyen, Rohit G. Jadhav, Song Lin, Henry S. White, Shelley D. Minteer Aug 2023

Unraveling Hydrogen Atom Transfer Mechanisms With Voltammetry: Oxidative Formation And Reactivity Of Cobalt Hydride, Dylan G. Boucher, Andrew D. Pendergast, Xiangyu Wu, Zachary A. Nguyen, Rohit G. Jadhav, Song Lin, Henry S. White, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

The utility of transition metal hydride catalyzed hydrogen atom transfer (MHAT) has been widely demonstrated in organic transformations such as alkene isomerization and hydro functionalization reactions. However, the highly reactive nature of the hydride and radical intermediates has hindered mechanistic insight into this pivotal reaction. Recent advances in electrochemical MHAT have opened up the possibility for new analytical approaches for mechanistic diagnosis. Here, we report a voltametric interrogation of Co-Based MHAT reactivity, describing in detail the oxidative formation and reactivity of the key Co-H intermediate and its reaction with aryl alkenes. Insights from cyclic voltammetry and finite element simulations help …

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Enhancing The Performance Of Microbial Fuel Cells Via Metabolic Engineering Of Escherichia Coli For Phenazine Production, Olja Simoska, Dale A. Cummings, Erin M. Gaffney, Claire Langue, Tommy G. Primo, Courtney J. Weber, Corbin E. Witt, Shelley D. Minteer Aug 2023

Enhancing The Performance Of Microbial Fuel Cells Via Metabolic Engineering Of Escherichia Coli For Phenazine Production, Olja Simoska, Dale A. Cummings, Erin M. Gaffney, Claire Langue, Tommy G. Primo, Courtney J. Weber, Corbin E. Witt, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

One of the central roles in the design, development, and application advances in mediator-Based microbial electrochemical systems, such as microbial fuel cells (MFCs), is the establishment of efficient and successful communication between conductive electrode surfaces and microorganisms via modes of extracellular electron transfer (EET). Most microbial-Based systems require the use of artificial electroactive mediators in order to facilitate and/or enhance electron transfer. Our previous work established an exogenous phenazine-Based library as a mediator system to enable EET from the model microorganism Escherichia coli as a promising biotechnological host. However, the addition of exogenous mediators to a microbial electrochemical system has …

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Crystal Environment Induced Symmetry Reduction (Ceisr): Deep Analysis Of Para-Chloroacetophenone Azine And Generalization, Harmeet Bhoday, Kaidi Yang, Steven P. Kelley, Rainer Glaser Aug 2023

Crystal Environment Induced Symmetry Reduction (Ceisr): Deep Analysis Of Para-Chloroacetophenone Azine And Generalization, Harmeet Bhoday, Kaidi Yang, Steven P. Kelley, Rainer Glaser

Chemistry Faculty Research & Creative Works

The morphologies of sixteen crystal structures of ten symmetrical Xpara-Ph-(Me)C 00000000 00000000 00000000 00000000 11111111 = N-N = C (Me)-Ph-Xpara azines: 1 (Cl), 2 (Br), 3 (I), 4 (OH), 5 (PhO), 6 (CF3), 7 (F), 8 (Me), 9 (NO2), and 10 (PrO) are described. All the azines crystallize forming idioteloamphiphile monolayers (IAMs) and their morphologies fall into the two main classes of "flat" and "shiplap" depending on the lateral offsets between next neighbors in the monolayer. Ab initio studies show that the (E,E)-configured p-disubstituted acetophenone azines are C2-symmetric in the gas phase and that the azine and phenyl twists are …

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Libra: Harvesting Idle Resources Safely And Timely In Serverless Clusters, Hanfei Yu, Christian Fontenot, Hao Wang, Jian Li, Xu Yuan, Seung Jong Park Aug 2023

Libra: Harvesting Idle Resources Safely And Timely In Serverless Clusters, Hanfei Yu, Christian Fontenot, Hao Wang, Jian Li, Xu Yuan, Seung Jong Park

Computer Science Faculty Research & Creative Works

Serverless computing has been favored by users and infrastructure providers from various industries, including online services and scientific computing. Users enjoy its auto-scaling and ease-of-management, and providers own more control to optimize their service. However, existing serverless platforms still require users to pre-define resource allocations for their functions, leading to frequent misconfiguration by inexperienced users in practice. Besides, functions' varying input data further escalate the gap between their dynamic resource demands and static allocations, leaving functions either over-provisioned or under-provisioned. This paper presents Libra, a safe and timely resource harvesting framework for multi-node serverless clusters. Libra makes precise harvesting decisions …

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Discovery Of Gamma Rays From The Quiescent Sun With Hawc, A. Albert, R. Alfaro, C. Alvarez, J. C. Arteaga-Velázquez, D. Avila Rojas, H. A. Ayala Solares, R. Babu, E. Belmont-Moreno, C. Brisbois, K. S. Caballero-Mora, T. Capistrán, A. Carramiñana, S. Casanova, O. Chaparro-Amaro, U. Cotti, J. Cotzomi, S. Coutiño De León, E. De La Fuente, R. Diaz Hernandez, B. L. Dingus, M. A. Duvernois, M. Durocher, J. C. Diaz-Velez, R. W. Ellsworth, K. Engel, C. Espinoza, K. L. Fan, K. Fang, M. Fernandez Alonso, H. Fleischhack, N. Fraija, J. A. Garcia-Gonzalez, F. Garfias, M. M. Gonzalez, J. A. Goodman, J. P. Harding, S. Hernandez, J. Hinton, D. Huang, F. Hueyotl-Zahuantitla, P. Huntemeyer, A. Iriarte, V. Joshi, S. Kaufmann, J. Lee, J. T. Linnemann, A. L. Longinotti, G. Luis-Raya, K. Malone, O. Martinez, J. Martinez-Castro, J. A. Matthews, P. Miranda-Romagnoli, J. A. Morales-Soto, E. Moreno, M. Mostafa, A. Nayerhoda, L. Nellen, M. U. Nisa, R. Noriega-Papaqui, L. Olivera-Nieto, N. Omodei, Y. Perez Araujo, E. G. Perez-Perez, C. D. Rho, D. Rosa-Gonzalez, E. Ruiz-Velasco, H. Salazar, D. Salazar-Galeggos, A. Sandoval, M. Schneider, J. Serna-Franco, A. J. Smith, Y. Son, R. W. Springer, O. Tibolla, K. Tollefson, I. Torres, R. Torres-Escobedo, R. Turner, F. Urena-Mena, E. Varela, J. Villasenor, Xiaojie Wang, I. J. Watson, E. Willox, S. Yun-Carcamo, H. Zhou, C. De Leon Aug 2023

Discovery Of Gamma Rays From The Quiescent Sun With Hawc, A. Albert, R. Alfaro, C. Alvarez, J. C. Arteaga-Velázquez, D. Avila Rojas, H. A. Ayala Solares, R. Babu, E. Belmont-Moreno, C. Brisbois, K. S. Caballero-Mora, T. Capistrán, A. Carramiñana, S. Casanova, O. Chaparro-Amaro, U. Cotti, J. Cotzomi, S. Coutiño De León, E. De La Fuente, R. Diaz Hernandez, B. L. Dingus, M. A. Duvernois, M. Durocher, J. C. Diaz-Velez, R. W. Ellsworth, K. Engel, C. Espinoza, K. L. Fan, K. Fang, M. Fernandez Alonso, H. Fleischhack, N. Fraija, J. A. Garcia-Gonzalez, F. Garfias, M. M. Gonzalez, J. A. Goodman, J. P. Harding, S. Hernandez, J. Hinton, D. Huang, F. Hueyotl-Zahuantitla, P. Huntemeyer, A. Iriarte, V. Joshi, S. Kaufmann, J. Lee, J. T. Linnemann, A. L. Longinotti, G. Luis-Raya, K. Malone, O. Martinez, J. Martinez-Castro, J. A. Matthews, P. Miranda-Romagnoli, J. A. Morales-Soto, E. Moreno, M. Mostafa, A. Nayerhoda, L. Nellen, M. U. Nisa, R. Noriega-Papaqui, L. Olivera-Nieto, N. Omodei, Y. Perez Araujo, E. G. Perez-Perez, C. D. Rho, D. Rosa-Gonzalez, E. Ruiz-Velasco, H. Salazar, D. Salazar-Galeggos, A. Sandoval, M. Schneider, J. Serna-Franco, A. J. Smith, Y. Son, R. W. Springer, O. Tibolla, K. Tollefson, I. Torres, R. Torres-Escobedo, R. Turner, F. Urena-Mena, E. Varela, J. Villasenor, Xiaojie Wang, I. J. Watson, E. Willox, S. Yun-Carcamo, H. Zhou, C. De Leon

Physics Faculty Research & Creative Works

We report the first detection of a TeV γ-ray flux from the solar disk (6.3σ), based on 6.1 years of data from the High-Altitude Water Cherenkov (HAWC) observatory. The 0.5-2.6 TeV spectrum is well fit by a power law, dN/dE=A(E/1 TeV)-γ, with A=(1.6±0.3)x10-12 TeV-1 cm-2 s-1 and γ=3.62±0.14. The flux shows a strong indication of anticorrelation with solar activity. These results extend the bright, hard GeV emission from the disk observed with Fermi-LAT, seemingly due to hadronic Galactic cosmic rays showering on nuclei in the solar atmosphere. However, current theoretical models are unable to explain the details of how solar …

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Doubly Differential Ionization In Proton-Helium Collisions At Intermediate Energies: Energy Distribution Of Emitted Electrons As A Function Of Scattered-Projectile Angle, K. H. Spicer, C. T. Plowman, Michael Schulz, A. S. Kadyrov Aug 2023

Doubly Differential Ionization In Proton-Helium Collisions At Intermediate Energies: Energy Distribution Of Emitted Electrons As A Function Of Scattered-Projectile Angle, K. H. Spicer, C. T. Plowman, Michael Schulz, A. S. Kadyrov

Physics Faculty Research & Creative Works

Differential studies of the proton-helium scattering problem using the two-center wave-packet convergent close-coupling approach is extended to the calculation of the ionization cross section differential in the electron emission energy and the projectile scattering angle. The results obtained using the correlated two-electron and effective one-electron methods are in reasonably good agreement with experiment. While the shape of the doubly differential cross section generally agrees with the results of the experiment, at some emission energies its magnitude does not. This appears consistent with similar disagreement seen in the singly differential cross section at the same emission energies.

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Quantum Electrodynamic Corrections To Cyclotron States In A Penning Trap, Ulrich D. Jentschura, Christopher Moore Aug 2023

Quantum Electrodynamic Corrections To Cyclotron States In A Penning Trap, Ulrich D. Jentschura, Christopher Moore

Physics Faculty Research & Creative Works

We analyze the leading and higher-order quantum electrodynamic corrections to the energy levels for a single electron bound in a Penning trap, including the Bethe logarithm correction due to virtual excitations of the reference quantum cyclotron state. The effective coupling parameter αc in the Penning trap is identified as the square root of the ratio of the cyclotron frequency, converted to an energy via multiplication by the Planck constant, to the electron rest mass energy. We find a large, state-independent, logarithmic one-loop self-energy correction of order α αc4mc2ln(αc-2), where m is the …

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Outgassing Behavior And Heat Treatment Optimization Of Jsc-1a Lunar Regolith Simulant, Ryan P. Wilkerson, Mihail P. Petkov, Gerald E. Voecks, Catherine S. Lynch, Holly S. Shulman, Santhoshkumar Sundaramoorthy, Amitava Choudhury, Douglas L. Rickman, Michael R. Effinger Aug 2023

Outgassing Behavior And Heat Treatment Optimization Of Jsc-1a Lunar Regolith Simulant, Ryan P. Wilkerson, Mihail P. Petkov, Gerald E. Voecks, Catherine S. Lynch, Holly S. Shulman, Santhoshkumar Sundaramoorthy, Amitava Choudhury, Douglas L. Rickman, Michael R. Effinger

Chemistry Faculty Research & Creative Works

As NASA Strives towards a Long Duration Presence on the Moon, It Has Become Increasingly Important to Learn How to Better Utilize Resources from the Lunar Surface for Everything from Habitats, Vehicle Infrastructure, and Chemical Extraction. to that End, a Variety of Lunar Simulants Have Been Sourced from Terrestrially Available Volcanic Minerals and Glass as Apollo Regolith is Unavailable for Experimentation Needing Large Masses. However, While Mineralogy and Chemical Composition Can Approach that of Lunar Material in These Simulants, There Are Still Distinct Non-Lunar Phases Such as Hydrates, Carbonates, Sulfates, and Clays that Can Cause Simulants to Behave Distinctly Non-Lunar …

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An Integrated Finite Element Method And Machine Learning Algorithm For Brain Morphology Prediction, Poorya Chavoshnejad, Liangjun Chen, Xiaowei Yu, Jixin Hou, Nicholas Filla, Dajiang Zhu, Tianming Liu, Gang Li, Mir Jalil Razavi, Xianqiao Wang Aug 2023

An Integrated Finite Element Method And Machine Learning Algorithm For Brain Morphology Prediction, Poorya Chavoshnejad, Liangjun Chen, Xiaowei Yu, Jixin Hou, Nicholas Filla, Dajiang Zhu, Tianming Liu, Gang Li, Mir Jalil Razavi, Xianqiao Wang

Computer Science Faculty Research & Creative Works

The human brain development experiences a complex evolving cortical folding from a smooth surface to a convoluted ensemble of folds. Computational modeling of brain development has played an essential role in better understanding the process of cortical folding but still leaves many questions to be answered. A major challenge faced by computational models is how to create massive brain developmental simulations with affordable computational sources to complement neuroimaging data and provide reliable predictions for brain folding. In this study, we leveraged the power of machine learning in data augmentation and prediction to develop a machine-learning-based finite element surrogate model to …

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Understanding Formation And Roles Of Niᴵᴵ Aryl Amido And Niiii Aryl Amido Intermediates In Ni-Catalyzed Electrochemical Aryl Amination Reactions, Jian Luo, Michael T. Davenport, Chad Callister, Shelley D. Minteer, Daniel H. Ess, T. Leo Liu Jul 2023

Understanding Formation And Roles Of Niᴵᴵ Aryl Amido And Niiii Aryl Amido Intermediates In Ni-Catalyzed Electrochemical Aryl Amination Reactions, Jian Luo, Michael T. Davenport, Chad Callister, Shelley D. Minteer, Daniel H. Ess, T. Leo Liu

Chemistry Faculty Research & Creative Works

Ni-catalyzed electrochemical aryl amination (e-amination) is an attractive, emerging approach to building C-N bonds. Here, we report in-depth experimental and computational studies that examined the mechanism of Ni-catalyzed e-amination reactions. Key NiII-amine dibromide and NiII aryl amido intermediates were chemically synthesized and characterized. the combination of experiments and DFT calculations suggest (1) there is coordination of an amine to the NiII catalyst before the cathodic reduction and oxidative addition steps, (2) a stable NiII aryl amido intermediate is produced from the cathodic half-reaction, a critical step in controlling the selectivity between cross-coupling and undesired homo-coupling reaction pathways, (3) the diazabicycloundecene …

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Neuro-Symbolic Representations For Information Retrieval, Laura Dietz, Hannah Bast, Shubham Chatterjee, Jeff Dalton, Jian Yun Nie, Rodrigo Nogueira Jul 2023

Neuro-Symbolic Representations For Information Retrieval, Laura Dietz, Hannah Bast, Shubham Chatterjee, Jeff Dalton, Jian Yun Nie, Rodrigo Nogueira

Computer Science Faculty Research & Creative Works

This tutorial will provide an overview of recent advances on neuro-symbolic approaches for information retrieval. A decade ago, knowledge graphs and semantic annotations technology led to active research on how to best leverage symbolic knowledge. At the same time, neural methods have demonstrated to be versatile and highly effective. From a neural network perspective, the same representation approach can service document ranking or knowledge graph reasoning. End-to-end training allows to optimize complex methods for downstream tasks. We are at the point where both the symbolic and the neural research advances are coalescing into neuro-symbolic approaches. The underlying research questions are …

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Generative Relevance Feedback With Large Language Models, Iain Mackie, Shubham Chatterjee, Jeffrey Dalton Jul 2023

Generative Relevance Feedback With Large Language Models, Iain Mackie, Shubham Chatterjee, Jeffrey Dalton

Computer Science Faculty Research & Creative Works

Current query expansion models use pseudo-relevance feedback to improve first-pass retrieval effectiveness; however, this fails when the initial results are not relevant. Instead of building a language model from retrieved results, we propose Generative Relevance Feedback (GRF) that builds probabilistic feedback models from long-form text generated from Large Language Models. We study the effective methods for generating text by varying the zero-shot generation subtasks: queries, entities, facts, news articles, documents, and essays. We evaluate GRF on document retrieval benchmarks covering a diverse set of queries and document collections, and the results show that GRF methods significantly outperform previous PRF methods. …

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Detecting Mental Distresses Using Social Behavior Analysis In The Context Of Covid-19: A Survey, Sahraoui Dhelim, Liming Chen, Sajal K. Das, Huansheng Ning, Chris Nugent, Gerard Leavey, Dirk Pesch, Eleanor Bantry-White, Devin Michael Burns Jul 2023

Detecting Mental Distresses Using Social Behavior Analysis In The Context Of Covid-19: A Survey, Sahraoui Dhelim, Liming Chen, Sajal K. Das, Huansheng Ning, Chris Nugent, Gerard Leavey, Dirk Pesch, Eleanor Bantry-White, Devin Michael Burns

Computer Science Faculty Research & Creative Works

Online social media provides a channel for monitoring people's social behaviors from which to infer and detect their mental distresses. During the COVID-19 pandemic, online social networks were increasingly used to express opinions, views, and moods due to the restrictions on physical activities and in-person meetings, leading to a significant amount of diverse user-generated social media content. This offers a unique opportunity to examine how COVID-19 changed global behaviors regarding its ramifications on mental well-being. In this article, we surveyed the literature on social media analysis for the detection of mental distress, with a special emphasis on the studies published …

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Cationic Divalent Metal Sites (M = Mn, Fe, Co) Operating As Both Nitrene-Transfer Agents And Lewis Acids Toward Mediating The Synthesis Of Three- And Five-Membered N-Heterocycles, Suraj Kumar Sahoo, Brent Harfmann, Lin Ai, Qiuwen Wang, Sudip Mohapatra, Amitava Choudhury, Pericles Stavropoulos Jul 2023

Cationic Divalent Metal Sites (M = Mn, Fe, Co) Operating As Both Nitrene-Transfer Agents And Lewis Acids Toward Mediating The Synthesis Of Three- And Five-Membered N-Heterocycles, Suraj Kumar Sahoo, Brent Harfmann, Lin Ai, Qiuwen Wang, Sudip Mohapatra, Amitava Choudhury, Pericles Stavropoulos

Chemistry Faculty Research & Creative Works

The tripodal compounds [(TMG3trphen)MII-solv](PF6)2 (M = Mn, Fe, Co; solv = MeCN, DMF) and bipodal analogues [(TMG2biphen)MII(NCMe)x](PF6)2 (x = 3 for Mn, Fe; x = 2 for Co) and [(TMG2biphen)MIICl2] have been synthesized with ligands that feature a triaryl- or diarylmethyl-amine framework and superbasic tetramethylguanidinyl residues (TMG). The dicationic M(II) sites mediate catalytic nitrene-transfer reactions between the imidoiodinane PhI═NTs (Ts = tosyl) and a panel of styrenes in MeCN to afford aziridines and low yields of imidazolines (upon …

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Logarithmic Terms In Atom-Surface Potentials: Limited Applicability Of Rational Approximations For Intermediate Distance, Ulrich D. Jentschura, C. Moore Jul 2023

Logarithmic Terms In Atom-Surface Potentials: Limited Applicability Of Rational Approximations For Intermediate Distance, Ulrich D. Jentschura, C. Moore

Physics Faculty Research & Creative Works

It is usually assumed that interaction potentials, in general, and atom-surface potential, in particular, can be expressed in terms of an expansion involving integer powers of the distance between the two interacting objects. Here, we show that, in the short-range expansion of the interaction potential of a neutral atom and a dielectric surface, logarithms of the atom-wall distance appear. These logarithms are accompanied with logarithmic sums over virtual excitations of the atom interacting with the surface in analogy to Bethe logarithms in quantum electrodynamics. We verify the presence of the logarithmic terms in the short-range expansion using a model problem …

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