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Four-Decades Of Bed Elevation Changes In The Heavily Regulated Upper Atchafalaya River, Louisiana, Usa, Y. Jun Xu, Bo Wang, Wei Xu, Ming Tang, Frank T.C. Tsai, Laurence C. Smith Aug 2021

Four-Decades Of Bed Elevation Changes In The Heavily Regulated Upper Atchafalaya River, Louisiana, Usa, Y. Jun Xu, Bo Wang, Wei Xu, Ming Tang, Frank T.C. Tsai, Laurence C. Smith

Faculty Publications

Previous studies have established that under natural conditions, alluvial river confluence zones experience channel scour followed by mid-channel bar development. Less attention is given to bed evolution downstream of large alluvial river confluences under engineered conditions, such as discharge regulation and levee confinement. Here we present four decades of morphologic changes along the 69-km uppermost Atchafalaya River, a downstream distributary of the confluence of the Mississippi River Outflow channel and the Red River. We aim to find the answer to one critical question: how does the channel bed downstream of an engineering-controlled confluence respond to regulated flow? We utilize single-beam …

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The Role Of Reduced Methionine In Mediating The Metabolic Responses To Protein Restriction Using Different Sources Of Protein, Han Fang, Kirsten P. Stone, Sujoy Ghosh, Laura A. Forney, Thomas W. Gettys Aug 2021

The Role Of Reduced Methionine In Mediating The Metabolic Responses To Protein Restriction Using Different Sources Of Protein, Han Fang, Kirsten P. Stone, Sujoy Ghosh, Laura A. Forney, Thomas W. Gettys

Division of Basic Science Faculty Publications

Dietary protein restriction and dietary methionine restriction (MR) produce a comparable series of behavioral, physiological, biochemical, and transcriptional responses. Both dietary regimens produce a similar reduction in intake of sulfur amino acids (e.g., methionine and cystine), and both diets increase expression and release of hepatic FGF21. Given that FGF21 is an essential mediator of the metabolic phenotype produced by both diets, an important unresolved question is whether dietary protein restriction represents de facto methionine restriction. Using diets formulated from either casein or soy protein with matched reductions in sulfur amino acids, we compared the ability of the respective diets to …

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Range-Wide Population Genetic Analysis Of Seaside Sparrows (Ammospiza Maritima) Supports At Least Five Distinct Population Segments That Do Not Align With Current Subspecies Descriptions, Kathryn E.C. Davis, Amie E. Settlecowski, Mackenzie R. Roeder, Carolyn Enloe, Thomas Virzi, Margaret E. Hunter, Stefan Woltmann, Sabrina S. Taylor Aug 2021

Range-Wide Population Genetic Analysis Of Seaside Sparrows (Ammospiza Maritima) Supports At Least Five Distinct Population Segments That Do Not Align With Current Subspecies Descriptions, Kathryn E.C. Davis, Amie E. Settlecowski, Mackenzie R. Roeder, Carolyn Enloe, Thomas Virzi, Margaret E. Hunter, Stefan Woltmann, Sabrina S. Taylor

Faculty Publications

As an obligate salt marsh species, Seaside Sparrows (Ammospiza maritima) are vulnerable to numerous threats including climate change, coastal erosion, sea-level rise, and both natural and anthropogenic disasters. Of the 9 recognized subspecies, 2 are extinct and 1 is endangered. Previous genetic analyses of mitochondrial DNA (mtDNA) and microsatellite loci showed that current taxonomy does not accurately reflect underlying genetic diversity, with possible consequences for the distribution of conservation resources. To further inform Seaside Sparrow management, we comprehensively describe genetic structure among 24 range-wide sampling locations that include all extant subspecies. We inferred population structure from several thousand single-nucleotide polymorphisms …

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Novel Sources Of Pre-Harvest Sprouting Resistance For Japonica Rice Improvement, Jae Sung Lee, Dmytro Chebotarov, Kenneth L. Mcnally, Valerien Pede, Tri Deri Setiyono, Rency Raquid, Woong Jo Hyun, Ji Ung Jeung, Ajay Kohli, Youngjun Mo Aug 2021

Novel Sources Of Pre-Harvest Sprouting Resistance For Japonica Rice Improvement, Jae Sung Lee, Dmytro Chebotarov, Kenneth L. Mcnally, Valerien Pede, Tri Deri Setiyono, Rency Raquid, Woong Jo Hyun, Ji Ung Jeung, Ajay Kohli, Youngjun Mo

Faculty Publications

Pre-harvest sprouting (PHS), induced by unexpected weather events, such as typhoons, at the late seed maturity stage, is becoming a serious threat to rice production, especially in the state of California, USA, Japan, and the Republic of Korea, where japonica varieties (mostly susceptible to PHS) are mainly cultivated. A projected economic loss by severe PHS in these three countries could range between 8–10 billion USD per year during the next 10 years. Here, we present promising rice germplasm with strong resistance to PHS that were selected from a diverse rice panel of accessions held in the International Rice Genebank (IRG) …

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Novel Epigenetic Link Between Gestational Diabetes Mellitus And Macrosomia, Brian T. Joyce, Huikun Liu, Leishen Wang, Jun Wang, Yinan Zheng, Drew Nannini, Alex Drong, Stephanie Shiau, Weiqin Li, Junhong Leng, Yun Shen, Ru Gao, Andrea Baccarelli, Gang Hu, Lifang Hou Aug 2021

Novel Epigenetic Link Between Gestational Diabetes Mellitus And Macrosomia, Brian T. Joyce, Huikun Liu, Leishen Wang, Jun Wang, Yinan Zheng, Drew Nannini, Alex Drong, Stephanie Shiau, Weiqin Li, Junhong Leng, Yun Shen, Ru Gao, Andrea Baccarelli, Gang Hu, Lifang Hou

Population and Public Health Science Faculty Publications

Background & objectives: Examine maternal gestational diabetes mellitus (GDM), macrosomia and DNA methylation in candidate genes IGF1, IGF2, H19, ARHGRF11, MEST, NR3C1, ADIPOQ and RETN. Materials & methods: A total of 1145 children (572 GDM cases and 573 controls) from the Tianjin GDM study, including 177 with macrosomia, had blood DNA collection at median age 5.9 (range: 3.1-10.0). We used logistic regression to screen for associations with GDM and model macrosomia on 37 CpGs, and performed mediation analysis. Results: One CpG was associated with macrosomia at false discovery rate (FDR) < 0.05 (cg14428359 in MEST); two (cg19466922 in MEST and cg26263166 in IGF2) were associated at p < 0.05 but mediated 26 and 13%, respectively. Conclusion: MEST and IGF2 were previously identified for potential involvement in fetal growth and development (Trial Registration number: NCT01554358 [ClinicalTrials.gov]).

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Trends In Self-Reported Sitting Time By Physical Activity Levels Among Us Adults, Nhanes 2007/2008-2017/2018, Emily N. Ussery, Geoffrey P. Whitfield, Janet E. Fulton, Deborah A. Galuska, Charles E. Matthews, Peter T. Katzmarzyk, A. Carlson Aug 2021

Trends In Self-Reported Sitting Time By Physical Activity Levels Among Us Adults, Nhanes 2007/2008-2017/2018, Emily N. Ussery, Geoffrey P. Whitfield, Janet E. Fulton, Deborah A. Galuska, Charles E. Matthews, Peter T. Katzmarzyk, A. Carlson

Population and Public Health Science Faculty Publications

Background: High levels of sedentary behavior and physical inactivity increase the risk of premature mortality and several chronic diseases. Monitoring national trends and correlates of sedentary behavior and physical inactivity can help identify patterns of risk in the population over time. Methods: The authors used self-reported data from the National Health and Nutrition Examination Surveys (2007/2008-2017/2018) to estimate trends in US adults' mean daily sitting time, overall, and stratified by levels of leisure-time and multidomain physical activity, and in the joint prevalence of high sitting time (>8 h/d) and physical inactivity. Trends were tested using orthogonal polynomial contrasts. Results: …

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Lipids Activate Skeletal Muscle Mitochondrial Fission And Quality Control Networks To Induce Insulin Resistance In Humans, Christopher L. Axelrod, Ciaran E. Fealy, Melissa L. Erickson, Gangarao Davuluri, Hisashi Fujioka, Wagner S. Dantas, Emily Huang, Kathryn Pergola, Jacob T. Mey, William T. King, Anny Mulya, Daniel Hsia, Bartolome Burguera, Bernard Tandler, Charles L. Hoppel, John P. Kirwan Aug 2021

Lipids Activate Skeletal Muscle Mitochondrial Fission And Quality Control Networks To Induce Insulin Resistance In Humans, Christopher L. Axelrod, Ciaran E. Fealy, Melissa L. Erickson, Gangarao Davuluri, Hisashi Fujioka, Wagner S. Dantas, Emily Huang, Kathryn Pergola, Jacob T. Mey, William T. King, Anny Mulya, Daniel Hsia, Bartolome Burguera, Bernard Tandler, Charles L. Hoppel, John P. Kirwan

Division of Basic Science Faculty Publications

Background and aims: A diminution in skeletal muscle mitochondrial function due to ectopic lipid accumulation and excess nutrient intake is thought to contribute to insulin resistance and the development of type 2 diabetes. However, the functional integrity of mitochondria in insulin-resistant skeletal muscle remains highly controversial. Methods: 19 healthy adults (age:28.4 ± 1.7 years; BMI:22.7 ± 0.3 kg/m2) received an overnight intravenous infusion of lipid (20% Intralipid) or saline followed by a hyperinsulinemic-euglycemic clamp to assess insulin sensitivity using a randomized crossover design. Skeletal muscle biopsies were obtained after the overnight lipid infusion to evaluate activation of mitochondrial dynamics proteins, …

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Phytosampling—A Supplementary Tool For Particulate Matter (Pm) Speciation Characterization, Chuqi Guo, Farhana Hasan, Dean Lay, Albert Leo N. Dela Cruz, Ajit Ghimire, Slawo M. Lomnicki Aug 2021

Phytosampling—A Supplementary Tool For Particulate Matter (Pm) Speciation Characterization, Chuqi Guo, Farhana Hasan, Dean Lay, Albert Leo N. Dela Cruz, Ajit Ghimire, Slawo M. Lomnicki

Faculty Publications

Ambient air particulate matter (PM) and PM-associated environmentally persistent free radicals (EPFRs) have been documented to contribute to pollution-related health effects. Studies of ambient air PM potentially bear artifacts stemming from the collection methods. We have investigated the applicability of PM phytosampling (PHS) as a supplementary tool to a classic PM sampler in respect of achieving better PM chemical composition assessment (primarily organic fraction). Phytosampling is a static PM collection method relying on the particle entrapment by the plant’s leaf through electrostatic forces and surface trichomes. We have investigated the differences in the EPFR and polycyclic aromatic hydrocarbon (PAH) speciation …

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Honeycomb Structures In Magnetic Fields, Becker Simon, Rui Han, Svetlana Jitomirskaya, Maciej Zworski Aug 2021

Honeycomb Structures In Magnetic Fields, Becker Simon, Rui Han, Svetlana Jitomirskaya, Maciej Zworski

Faculty Publications

We consider the nearest-neighbour tight binding model of the honeycomb lattice in magnetic fields and discover surprizing new analytical results that fully explain fractal spectra and experimentally observed asymmetries in the density of states of molecular graphene.We describe a fractal Cantor spectrum for irrational magnetic flux through a honeycomb, and establish the existence of zero energy Dirac cones for each rational flux with fully explicit estimates on the cone angle. Our results give a substantially more refined description of subtleties in the de Haas-van Alphen and quantum Hall effects, and provide the first quantitative bounds on transport coefficients for the …

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Comparing Ultraconserved Elements And Exons For Phylogenomic Analyses Of Middle American Cichlids: When Data Agree To Disagree, Fernando Alda, William B. Ludt, Diego J. Elías, Caleb D. Mcmahan, Prosanta Chakrabarty Aug 2021

Comparing Ultraconserved Elements And Exons For Phylogenomic Analyses Of Middle American Cichlids: When Data Agree To Disagree, Fernando Alda, William B. Ludt, Diego J. Elías, Caleb D. Mcmahan, Prosanta Chakrabarty

Faculty Publications

Choosing among types of genomic markers to be used in a phylogenomic study can have a major influence on the cost, design, and results of a study. Yet few attempts have been made to compare categories of next-generation sequence markers limiting our ability to compare the suitability of these different genomic fragment types. Here, we explore properties of different genomic markers to find if they vary in the accuracy of component phylogenetic trees and to clarify the causes of conflict obtained from different data sets or inference methods. As a test case, we explore the causes of discordance between phylogenetic …

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Increased Ploidy Of Butomus Umbellatus In Introduced Populations Is Not Associated With Higher Phenotypic Plasticity To N And P, Nathan E. Harms, James T. Cronin, John F. Gaskin Aug 2021

Increased Ploidy Of Butomus Umbellatus In Introduced Populations Is Not Associated With Higher Phenotypic Plasticity To N And P, Nathan E. Harms, James T. Cronin, John F. Gaskin

Faculty Publications

Separate introductions or post-introduction evolution may lead to multiple invader genotypes or cytotypes that differ in growth rates, biomass or chemical profile responses (phenotype) to a range of environments. If the invader has high trait plasticity to a range of resource levels, then sediment N or P enrichment may enhance invasiveness. However, the ways in which ploidy, plasticity, and available N or P interact are unknown for most species despite the potential to explain spread and impacts by invaders with multiple introduced lineages. We conducted a common garden experiment with four triploid and six diploid populations of Butomus umbellatus, collected …

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Reducible Fermi Surface For Multi-Layer Quantum Graphs Including Stacked Graphene, Lee Fisher, Wei Li, Stephen P. Shipman Aug 2021

Reducible Fermi Surface For Multi-Layer Quantum Graphs Including Stacked Graphene, Lee Fisher, Wei Li, Stephen P. Shipman

Faculty Publications

We construct two types of multi-layer quantum graphs (Schrödinger operators on metric graphs) for which the dispersion function of wave vector and energy is proved to be a polynomial in the dispersion function of the single layer. This leads to the reducibility of the algebraic Fermi surface, at any energy, into several components. Each component contributes a set of bands to the spectrum of the graph operator. When the layers are graphene, AA-, AB-, and ABC-stacking are allowed within the same multi-layer structure. One of the tools we introduce is a surgery-type calculus for obtaining the dispersion function for a …

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Spectra Of Regular Quantum Trees: Rogue Eigenvalues And Dependence On Vertex Condition, Zhaoxia W. Hess, Stephen P. Shipman Aug 2021

Spectra Of Regular Quantum Trees: Rogue Eigenvalues And Dependence On Vertex Condition, Zhaoxia W. Hess, Stephen P. Shipman

Faculty Publications

We investigate the spectrum of Schrödinger operators on finite regular metric trees through a relation to orthogonal polynomials that provides a graphical perspective. As the Robin vertex parameter tends to -∞, a narrow cluster of finitely many eigenvalues tends to -∞, while the eigenvalues above this cluster remain bounded from below. Certain “rogue” eigenvalues break away from this cluster and tend even faster toward -∞. The spectrum can be visualized as the intersection points of two objects in the plane—a spiral curve depending on the Schrödinger potential, and a set of curves depending on the branching factor, the diameter of …

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Comparison Of Catalytic Activity For Treating Recalcitrant Organic Pollutant In Heterogeneous Fenton Oxidation With Iron-Impregnated Biochar And Activated Carbon, Jong Hwan Park, Jim J. Wang, Dong Cheol Seo Aug 2021

Comparison Of Catalytic Activity For Treating Recalcitrant Organic Pollutant In Heterogeneous Fenton Oxidation With Iron-Impregnated Biochar And Activated Carbon, Jong Hwan Park, Jim J. Wang, Dong Cheol Seo

Faculty Publications

Iron-impregnated biochar (Fe-BC) was developed through one-step pyrolysis, characterized, and directly compared with Fe-impregnated activated carbon (Fe-AC) for the removal of methylene blue (MB) in a heterogeneous Fenton reaction (HFR). Fe-BC exhibited significantly higher Fe impregnation efficiency than Fe-AC at the same pyrolysis temperature of 600 °C. Analyses via X-ray absorption near-edge spectroscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy revealed that both Fe-BC and Fe-AC contained Fe species such as Fe3O4, FeOOH, and Fe2O3, with Fe-BC having significantly more reduced Fe(II) than Fe-AC. This result is clear evidence that Fe-BC had better catalytic activity for MB than Fe-AC. The removal …

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Correction To: Female Reproductive Organs Of Brassica Napus Are More Sensitive Than Male To Transient Heat Stress (Euphytica, (2021), 217, 6, (117), 10.1007/S10681-021-02859-Z), Sheng Chen, Renu Saradadevi, Miriam S. Vidotti, Roberto Fritsche-Neto, Jose Crossa, Kadambot H.M. Siddique, Wallace A. Cowling Aug 2021

Correction To: Female Reproductive Organs Of Brassica Napus Are More Sensitive Than Male To Transient Heat Stress (Euphytica, (2021), 217, 6, (117), 10.1007/S10681-021-02859-Z), Sheng Chen, Renu Saradadevi, Miriam S. Vidotti, Roberto Fritsche-Neto, Jose Crossa, Kadambot H.M. Siddique, Wallace A. Cowling

Faculty Publications

The article Female reproductive organs of Brassica napus are more sensitive than male to transient heat stress, written by Sheng Chen, Renu Saradadevi, Miriam S. Vidotti, Roberto Fritsche-Neto, Jose Crossa, Kadambot H. M. Siddique, Wallace A. Cowling, was originally published Online First without Open Access. After publication in volume 217: 117 the author decided to opt for Open Choice and to make the article an Open Access publication. Therefore, the copyright of the article has been changed to © The Author(s) 2021 and the article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License, which …

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Optimal Control Of Volume-Preserving Mean Curvature Flow, Antoine Laurain, Shawn W. Walker Aug 2021

Optimal Control Of Volume-Preserving Mean Curvature Flow, Antoine Laurain, Shawn W. Walker

Faculty Publications

We develop a framework and numerical method for controlling the full space-time tube of a geometrically driven flow. We consider an optimal control problem for the mean curvature flow of a curve or surface with a volume constraint, where the control parameter acts as a forcing term in the motion law. The control of the trajectory of the flow is achieved by minimizing an appropriate tracking-type cost functional. The gradient of the cost functional is obtained via a formal sensitivity analysis of the space-time tube generated by the mean curvature flow. We show that the perturbation of the tube may …

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Bullying Experiences, Body Esteem, Body Dissatisfaction, And The Moderating Role Of Weight Status Among Adolescents, Lauren A. Fowler, Chelsea L. Kracht, Kara D. Denstel, Tiffany M. Stewart, Amanda E. Staiano Aug 2021

Bullying Experiences, Body Esteem, Body Dissatisfaction, And The Moderating Role Of Weight Status Among Adolescents, Lauren A. Fowler, Chelsea L. Kracht, Kara D. Denstel, Tiffany M. Stewart, Amanda E. Staiano

Population and Public Health Science Faculty Publications

Introduction: The present study examined the relationships between bullying victimization experiences, body esteem (BE), and body dissatisfaction (BD) by obesity status. Methods: Using a cross-sectional design, adolescents (10-16y) from the U.S. completed surveys. Weight and height were objectively assessed. Bullying was assessed using the Personal Experiences Checklist, with a total score that included three subscales (cyber, verbal-relational, and physical). BE was assessed using total score on the BE Scale, and BD was assessed using the Body Image Assessment for Pre-Adolescents, operationalized as the discrepancy between current and ideal body figure. Linear regression models, controlling for sociodemographics, were used to examine …

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Changes In Mood And Health-Related Quality Of Life In Look Ahead 6 Years After Termination Of The Lifestyle Intervention, Thomas A. Wadden, Ariana M. Chao, Harelda Anderson, Kirsten Annis, Karen Atkinson, Paula Bolin, Phillip Brantley, Jeanne M. Clark, Mace Coday, Gareth Dutton, John P. Foreyt, Edward W. Gregg, Helen P. Hazuda, James O. Hill, Van S. Hubbard, John M. Jakicic, Robert W. Jeffery, Karen C. Johnson, Steven E. Kahn, William C. Knowler, Mary Korytkowski, Cora E. Lewis, Blandine Laferrère, Roeland J. Middelbeek, Medha N. Munshi, David M. Nathan, Rebecca H. Neiberg, Scott J. Pilla, Anne Peters, Xavier Pi-Sunyer, Jack W. Rejeski, Bruce Redmon, Tiffany Stewart, Elizabeth Vaughan Aug 2021

Changes In Mood And Health-Related Quality Of Life In Look Ahead 6 Years After Termination Of The Lifestyle Intervention, Thomas A. Wadden, Ariana M. Chao, Harelda Anderson, Kirsten Annis, Karen Atkinson, Paula Bolin, Phillip Brantley, Jeanne M. Clark, Mace Coday, Gareth Dutton, John P. Foreyt, Edward W. Gregg, Helen P. Hazuda, James O. Hill, Van S. Hubbard, John M. Jakicic, Robert W. Jeffery, Karen C. Johnson, Steven E. Kahn, William C. Knowler, Mary Korytkowski, Cora E. Lewis, Blandine Laferrère, Roeland J. Middelbeek, Medha N. Munshi, David M. Nathan, Rebecca H. Neiberg, Scott J. Pilla, Anne Peters, Xavier Pi-Sunyer, Jack W. Rejeski, Bruce Redmon, Tiffany Stewart, Elizabeth Vaughan

Population and Public Health Science Faculty Publications

Objective: The Action for Health in Diabetes (Look AHEAD) study previously reported that intensive lifestyle intervention (ILI) reduced incident depressive symptoms and improved health-related quality of life (HRQOL) over nearly 10 years of intervention compared with a control group (the diabetes support and education group [DSE]) in participants with type 2 diabetes and overweight or obesity. The present study compared incident depressive symptoms and changes in HRQOL in these groups for an additional 6 years following termination of the ILI in September 2012. Methods: A total of 1,945 ILI participants and 1,900 DSE participants completed at least one of four …

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An Adaptive Data-Driven Controller For Underwater Manipulators With Variable Payload, Ignacio Carlucho, Dylan W. Stephens, Corina Barbalata Aug 2021

An Adaptive Data-Driven Controller For Underwater Manipulators With Variable Payload, Ignacio Carlucho, Dylan W. Stephens, Corina Barbalata

Faculty Publications

The underwater environment poses a complex problem for developing control systems for underwater manipulators. Modeling the system is a complicated and costly process due to the highly nonlinear dynamics and the presence of unknown hydrodynamical effects. Furthermore, manipulators are usually deployed on Autonomous Underwater Vehicles (AUVs) which further influence and change the dynamics of the arm. This is aggravated in underwater operations where manipulating different objects is necessary. These diverse manipulation tasks introduce external disturbances to the system and can lead to a fast degradation of the control system performance. In this article, we propose a novel adaptive controller for …

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Bilateral Privacy-Utility Tradeoff In Spectrum Sharing Systems: A Game-Theoretic Approach, Mengmeng Liu, Xiangwei Zhou, Mingxuan Sun Aug 2021

Bilateral Privacy-Utility Tradeoff In Spectrum Sharing Systems: A Game-Theoretic Approach, Mengmeng Liu, Xiangwei Zhou, Mingxuan Sun

Faculty Publications

In spectrum sharing systems based on spectrum trading, user locations are vital for the efficiency of dynamic channel reuse. However, both primary users (PUs) and secondary users (SUs) undertake the risk of location information leakage: a malicious PU may illegally collect SUs' location information to manipulate market decisions; a malicious SU would threat a PU's operational privacy by inferring the PU's location through seemingly inoffensive queries. To protect both PUs' and SUs' location information in spectrum trading, a bilateral privacy preservation framework is introduced in this paper. A game-theoretic approach based on the Stackelberg model is proposed to achieve the …

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Effectiveness Of Softening Agents For Enhancing Properties Of Asphalt Mixes With High Rap Contents, Zahid Hossain, Ashraf Elsayed, Sumon Roy Aug 2021

Effectiveness Of Softening Agents For Enhancing Properties Of Asphalt Mixes With High Rap Contents, Zahid Hossain, Ashraf Elsayed, Sumon Roy

Publications

A high percentage of reclaimed asphalt pavement (RAP) in new asphalt concrete can lead to developing premature failure of asphalt pavements due to fatigue or low-temperature cracking. The use of softening agents in asphalt binders can resolve these problems. The aim of this study is to evaluate the effectiveness of softening agents for enhancing the properties of asphalt mixes with high RAP contents. Two waste products, namely, waste cooking oil (WCO), and engine bottom oil (EBO) along with a commercially produced rejuvenator were investigated in this study. The following three types of Performance Grade (PG) binders, each collected from two …

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Feasibility Assessment Of Warm Mix Asphalt In Arkansas, Zahid Hossain, Ashraf Elsayed, Mohammad Najmush Sakib Oyan Aug 2021

Feasibility Assessment Of Warm Mix Asphalt In Arkansas, Zahid Hossain, Ashraf Elsayed, Mohammad Najmush Sakib Oyan

Publications

The future of Warm Mix Asphalt (WMA) technologies is promising in the U.S. However, the Arkansas Department of Transportation (ARDOT) does not have any specific guidelines to implement them in the field. This research aims to provide necessary baseline data for WMA as a proof of concept. In this study, three ARDOT approved Performance Grade (PG) binders namely PG 64-22, PG 70-22, and PG 76-22 were investigated. Each of these binders was obtained from two different sources. They were modified by varying doses of four selected additives: Sasobit®, Advera®, Evotherm®, and Rediset®. Additionally, four different types of aggregates (sandstone, limestone, …

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Development Of Cost-Effective High-Modulus Asphalt Concrete (Hmac) Mixtures Using Crumb Rubber And Local Construction Materials In Louisiana, Momen R. Mousa, Marwa Hassan, Ibrahim A.I.E Elnaml Aug 2021

Development Of Cost-Effective High-Modulus Asphalt Concrete (Hmac) Mixtures Using Crumb Rubber And Local Construction Materials In Louisiana, Momen R. Mousa, Marwa Hassan, Ibrahim A.I.E Elnaml

Publications

One of the emerging solutions to enhance the durability of asphalt pavements is the use of a French asphalt mix known as “High-Modulus Asphalt Concrete (HMAC).” This mix uses a hard asphalt binder, high binder content (about 6%), and low air voids content as compared to Superpave mixtures. The key objective of this study was to develop a cost-effective HMAC mixture using crumb rubber and local materials in Louisiana. To achieve this objective, four HMAC mixtures were prepared using two asphalt binders (PG 82-22 and PG 76-22 plus 10% crumb rubber) and two Reclaimed Asphalt Pavement (RAP) contents (20% and …

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Evaluation Of Alternative Sources Of Supplementary Cementitious Materials (Scms) For Concrete Materials In Transportation Infrastructure, Gabriel A. Arce, Miladin Radovic, Zahid Hossain, Marwa Hassan, Sujata Subedi Aug 2021

Evaluation Of Alternative Sources Of Supplementary Cementitious Materials (Scms) For Concrete Materials In Transportation Infrastructure, Gabriel A. Arce, Miladin Radovic, Zahid Hossain, Marwa Hassan, Sujata Subedi

Publications

Fly ash is the most utilized supplementary cementitious material (SCM) in the US. Nonetheless, rapid decline in coal-fired power generation threatens its supply. The objective of this study was to evaluate alternative SCMs for concrete transportation infrastructure in Region 6. SCMs investigated included reclaimed fly ash (RFA), reclaimed ground bottom ash (GBA), metakaolin (MK), and conventional Class F fly ash (FA) as a reference. SCMs were characterized and the fresh and hardened properties of concrete incorporating different dosages (i.e., 10, 20, and 30% cement replacement by mass) of the individual SCMs (i.e., binary systems) and blended SCM systems of RFA-MK …

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Resilient 3d-Printed Infrastructure With Engineered Cementitious Composites (Ecc), Maryam Hojati Aug 2021

Resilient 3d-Printed Infrastructure With Engineered Cementitious Composites (Ecc), Maryam Hojati

Publications

Conventional construction of reinforced concrete structures is slow, labor-intensive, and expensive. 3D printing holds great potential to assist engineers and architects in constructing fast and economical yet complex representational infrastructures. One of the most significant barriers to the broader adoption of concrete 3D printing in civil infrastructure is the difficulty of providing printed structural components with reinforcement to achieve sound structural performance under different loading conditions. Hence, it is essential to design concrete that can be utilized as a rebar-free material by considering strength and ductility. Recently, the development of Engineered Cementitious Composites (ECC) has neared the possibility to achieve …

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Evaluation Of Sustainable And Environmentally Friendly Stabilization Of Cohesionless Sandy Soil For Transportation Infrastructure, Miladin Radovic, Anand Puppala, Surya Sarat Chandra Congress, Jungyeon Jang, Oscar Huang Aug 2021

Evaluation Of Sustainable And Environmentally Friendly Stabilization Of Cohesionless Sandy Soil For Transportation Infrastructure, Miladin Radovic, Anand Puppala, Surya Sarat Chandra Congress, Jungyeon Jang, Oscar Huang

Publications

Ordinary Portland cement (OPC) is generally used to stabilize cohesionless sandy soils that are often found in coastal areas. Due to its high carbon footprint, many studies are being conducted to identify a suitable green alternative for stabilizing cohesionless soils. Previous studies have shown that partially replacing OPC with waste materials such as nano-silica and coal waste reduces the overall carbon footprint without significantly impacting the performance. Geopolymer (GP) received a lot of attention in the past few decades owing to its similar properties to that of OPC yet with a lower carbon footprint. This study investigated the feasibility of …

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An Automated System For Inspecting Rock Faces And Detecting Potential Rock Falls Using Machine Learning, John Stormont, Fernando Moreu, Amir Bagherieh, Roya Nasimi, Solomon Atcitty Aug 2021

An Automated System For Inspecting Rock Faces And Detecting Potential Rock Falls Using Machine Learning, John Stormont, Fernando Moreu, Amir Bagherieh, Roya Nasimi, Solomon Atcitty

Publications

Rockfall is a hazard in mountainous areas threatening infrastructure and human lives. Rockfall hazards are often mitigated by manual inspections using pry bars. The inspector must access the rock face, hit the rock surface, detect, and remove the loose rocks. This method is very labor demanding, unsafe, and challenging. This research presents a method that automatize the inspection of rock blocks that are prone to rockfall events. A robot is developed to replace the manual hammer tap process and collect the sound data remotely; subsequently, the sound signal is used to identify different types of the discontinuity in rocks in …

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Resource Guide For State Dot’S Maintenance Equipment Fleet Management Decisions, Yongwei Shan, Samir Ahmed, Lei Qiao Aug 2021

Resource Guide For State Dot’S Maintenance Equipment Fleet Management Decisions, Yongwei Shan, Samir Ahmed, Lei Qiao

Publications

This research created a guide for state Departments of Transportation fleet management on utilizing equipment fleet management system data to make informed fleet management decisions. The research team took the historical equipment fleet data from the Oklahoma Department of Transportation and developed workflows, algorithms, and examples to demonstrate the use of historical equipment data for equipment decisions. Specifically, the research team demonstrated 1) the use of life cycle analysis and dynamic programming models for equipment replacement decisions; 2) developed algorithms to calculate equipment rental rates that can be used by the Department to forecast and allocate equipment operational budget among …

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Preventing Struck-By Hazards: Defying Risk-Habituation Via Virtual Accident Simulation, Changbum Ahn Aug 2021

Preventing Struck-By Hazards: Defying Risk-Habituation Via Virtual Accident Simulation, Changbum Ahn

Publications

Repeated exposure to struck-by hazards in road work zones generates workers’ habituation to risks related to those hazards, a key contributor to accidents in road work zones. Thus, analyzing the development of risk habituation and providing proper intervention are crucial to preventing accidents in road work zones. In this context, this study employs a virtual reality (VR) environment as a behavioral intervention tool to investigate its effect on mitigating a decline in workers’ vigilance with habituation to hazards in workplaces. A virtual environment that simulates a road maintenance task was developed and used to repeatedly expose subjects to struck-by hazards …

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Bridge Cracks Monitoring: Detection, Measurement, And Comparison Using Augmented Reality, Fernando Moreu, Kaveh Malek Aug 2021

Bridge Cracks Monitoring: Detection, Measurement, And Comparison Using Augmented Reality, Fernando Moreu, Kaveh Malek

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Crack occurrence and propagation are among critical factors that affect the performance and lifespan of civil infrastructures such as bridges. Consequently, numerous crack detection and measurement methods have been proposed and developed in the recent decades in the areas of Structural Health Monitoring and non-destructive testing. Many novel technologies have emerged with the potential to overcome the limitations of the presented techniques of crack detection and characterization. Crack detection and characterization method used in this research lies in supplementing human visual inspection capabilities in a systematic manner through an appropriate level of automation. The Augmented Reality (AR) tool developed in …

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