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Natural Geochemical Markers Reveal Environmental History And Population Connectivity Of Common Cuttlefish In The Atlantic Ocean And Mediterranean Sea, Jay R. Rooker, R. J.David Wells, Piero Addis, Haritz Arrizabalaga, Miguel Baptista, Giovanni Bearzi, Michael A. Dance, Igaratza Fraile, Thomas Lacoue-Labarthe, Jessica M. Lee, Persefoni Megalofonou, Rui Rosa, Ignacio Sobrino, António V. Sykes, Roger Villanueva Jul 2020

Natural Geochemical Markers Reveal Environmental History And Population Connectivity Of Common Cuttlefish In The Atlantic Ocean And Mediterranean Sea, Jay R. Rooker, R. J.David Wells, Piero Addis, Haritz Arrizabalaga, Miguel Baptista, Giovanni Bearzi, Michael A. Dance, Igaratza Fraile, Thomas Lacoue-Labarthe, Jessica M. Lee, Persefoni Megalofonou, Rui Rosa, Ignacio Sobrino, António V. Sykes, Roger Villanueva

Faculty Publications

Natural markers (δ 13 C and δ 18 O stable isotopes) in the cuttlebones of the European common cuttlefish (Sepia officinalis) were determined for individuals collected across a substantial portion of their range in the Northeast Atlantic Ocean (NEAO) and Mediterranean Sea. Cuttlebone δ 13 C and δ 18 O were quantified for core and edge material to characterize geochemical signatures associated with early (juvenile) and recent (sub-adult/adult) life-history periods, respectively. Regional shifts in cuttlebone δ 13 C and δ 18 O values were detected across the 12 sites investigated. Individuals collected from sites in the NEAO displayed more enriched …

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Intraspecific And Biogeographical Variation In Foliar Fungal Communities And Pathogen Damage Of Native And Invasive Phragmites Australis, Warwick J. Allen, Aaron E. Devries, Nicholas J. Bologna, Wesley A. Bickford, Kurt P. Kowalski, Laura A. Meyerson, James T. Cronin Jul 2020

Intraspecific And Biogeographical Variation In Foliar Fungal Communities And Pathogen Damage Of Native And Invasive Phragmites Australis, Warwick J. Allen, Aaron E. Devries, Nicholas J. Bologna, Wesley A. Bickford, Kurt P. Kowalski, Laura A. Meyerson, James T. Cronin

Faculty Publications

© 2020 John Wiley & Sons Ltd Aim: Recent research has highlighted that the relationship between species interactions and latitude can differ between native and invasive plant taxa, generating biogeographical heterogeneity in community resistance to plant invasions. In the first study with foliar pathogens, we tested whether co-occurring native and invasive lineages of common reed (Phragmites australis) exhibit non-parallel latitudinal gradients in foliar fungal communities, pathogen susceptibility and damage, and whether these biogeographical patterns can influence the success of invasion. Location: North America. Time period: 2015–2017. Major taxa studied: Perennial grass P. australis. Methods: We surveyed 35 P. australis field …

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Dynamic Glucose Disposal Is Driven By Reduced Endogenous Glucose Production In Response To Voluntary Wheel Running: A Stable Isotope Approach, Timothy D. Allerton, Greg M. Kowalski, Hardy Hang, Jacqueline Stephens Jul 2020

Dynamic Glucose Disposal Is Driven By Reduced Endogenous Glucose Production In Response To Voluntary Wheel Running: A Stable Isotope Approach, Timothy D. Allerton, Greg M. Kowalski, Hardy Hang, Jacqueline Stephens

Faculty Publications

© 2020 the American Physiological Society. Dynamic glucose disposal is driven by reduced endogenous glucose production in response to voluntary wheel running: A stable isotope approach. Am J Physiol Endocrinol Metab 319: E2-E10, 2020. First published April 28, 2020; doi:10.1152/ajpendo.00450.2019.-To resolve both the systems level and molecular mechanisms responsible for exerciseinduced improvements in glucose tolerance, we sought to test the effect of voluntary wheel running exercise on postprandial glucose dynamics. We utilized a stable isotope-labeled oral glucose tolerance test (SI-OGTT) incorporating complementary deuterium glucose tracers at a 1:1 ratio (2-2H-glucose and 6-6 2H-glucose; 2g/kg lean body mass) to distinguish between …

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Β-Hydroxybutyrate Is Reduced In Humans With Obesity-Related Nafld And Displays A Dose-Dependent Effect On Skeletal Muscle Mitochondrial Respiration In Vitro, Jacob T. Mey, Melissa L. Erickson, Christopher L. Axelrod, William T. King, Chris A. Flask, Arthur J. Mccullough, John P. Kirwan Jul 2020

Β-Hydroxybutyrate Is Reduced In Humans With Obesity-Related Nafld And Displays A Dose-Dependent Effect On Skeletal Muscle Mitochondrial Respiration In Vitro, Jacob T. Mey, Melissa L. Erickson, Christopher L. Axelrod, William T. King, Chris A. Flask, Arthur J. Mccullough, John P. Kirwan

Division of Basic Science Faculty Publications

β-Hydroxybutyrate is reduced in humans with obesity-related NAFLD and displays a dose-dependent effect on skeletal muscle mitochondrial respiration in vitro. Am J Physiol Endocrinol Metab 319: E187-E195, 2020. First published May 12, 2020; doi:10.1152/ajpendo.00058.2020.-Nonalcoholic fatty liver disease (NAFLD) is characterized by hepatic fat accumulation and impaired insulin sensitivity. Reduced hepatic ketogenesis may promote these pathologies, but data are inconclusive in humans and the link between NAFLD and reduced insulin sensitivity remains obscure. We investigated individuals with obesity-related NAFLD and hypothesized that β-hydroxybutyrate (βOHB; the predominant ketone species) would be reduced and related to hepatic fat accumulation and insulin sensitivity. Furthermore, …

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Effectiveness Of Sodium-Glucose Co-Transporter-2 Inhibitors On Ischaemic Heart Disease, Yun Shen, Jian Zhou, Lizheng Shi, Elizabeth Nauman, Peter T. Katzmarzyk, Eboni G. Price-Haywood, Ronald Horswell, San Chu, Shengping Yang, Alessandra N. Bazzano, Somesh Nigam, Gang Hu Jul 2020

Effectiveness Of Sodium-Glucose Co-Transporter-2 Inhibitors On Ischaemic Heart Disease, Yun Shen, Jian Zhou, Lizheng Shi, Elizabeth Nauman, Peter T. Katzmarzyk, Eboni G. Price-Haywood, Ronald Horswell, San Chu, Shengping Yang, Alessandra N. Bazzano, Somesh Nigam, Gang Hu

Population and Public Health Science Faculty Publications

Aim: To compare the cardiovascular risks between users and non-users of sodium-glucose co-transporter-2 (SGLT2) inhibitors based on electronic medical record data from a large integrated healthcare system in South Louisiana. Materials and methods: Demographic, anthropometric, laboratory and medication prescription information for patients with type 2 diabetes who were new users of SGLT2 inhibitors, either as initial treatments or as add-on treatments, were obtained from electronic health records. Mediation analysis was performed to evaluate the association of use of SGLT2 inhibitors and changes of metabolic risk factors with the risk of incident ischaemic heart disease. Results: A total of 5338 new …

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Information-Theoretic Aspects Of The Generalized Amplitude-Damping Channel, Sumeet Khatri, Kunal Sharma, Mark M. Wilde Jul 2020

Information-Theoretic Aspects Of The Generalized Amplitude-Damping Channel, Sumeet Khatri, Kunal Sharma, Mark M. Wilde

Faculty Publications

The generalized amplitude-damping channel (GADC) is one of the sources of noise in superconducting-circuit-based quantum computing. It can be viewed as the qubit analog of the bosonic thermal channel, and it thus can be used to model lossy processes in the presence of background noise for low-temperature systems. In this work, we provide an information-theoretic study of the GADC. We first determine the parameter range for which the GADC is entanglement breaking and the range for which it is antidegradable. We then establish several upper bounds on its classical, quantum, and private capacities. These bounds are based on data-processing inequalities …

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Louisiana Agriculture Summer, 2020, Lsu Agcenter Jul 2020

Louisiana Agriculture Summer, 2020, Lsu Agcenter

Louisiana Agriculture

No abstract provided.

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Northwest- Summer 2020, Lsu Agcenter Jul 2020

Northwest- Summer 2020, Lsu Agcenter

Horticulture Hints

No abstract provided.

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Northeast- Summer 2020, Lsu Agcenter Jul 2020

Northeast- Summer 2020, Lsu Agcenter

Horticulture Hints

No abstract provided.

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Central- Summer 2020, Lsu Agcenter Jul 2020

Central- Summer 2020, Lsu Agcenter

Horticulture Hints

No abstract provided.

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Southwest- Summer 2020, Lsu Agcenter Jul 2020

Southwest- Summer 2020, Lsu Agcenter

Horticulture Hints

No abstract provided.

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Southeast- Summer 2020, Lsu Agcenter Jul 2020

Southeast- Summer 2020, Lsu Agcenter

Horticulture Hints

No abstract provided.

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Covid-19 Diagnostic Process In Mainland China: The Math Beyond Pneumonia, Feng Wu, Weishan Huang Jul 2020

Covid-19 Diagnostic Process In Mainland China: The Math Beyond Pneumonia, Feng Wu, Weishan Huang

Faculty Publications

No abstract provided.

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Benchmark Calculations Of Electromagnetic Sum Rules With A Symmetry-Adapted Basis And Hyperspherical Harmonics, R. B. Baker, K. D. Launey, S. Bacca, N. Nevo Dinur, T. Dytrych Jul 2020

Benchmark Calculations Of Electromagnetic Sum Rules With A Symmetry-Adapted Basis And Hyperspherical Harmonics, R. B. Baker, K. D. Launey, S. Bacca, N. Nevo Dinur, T. Dytrych

Faculty Publications

We demonstrate the ability to calculate electromagnetic sum rules with the ab initio symmetry-adapted no-core shell model. By implementing the Lanczos algorithm, we compute nonenergy weighted, energy weighted, and inverse energy weighted sum rules for electric monopole, dipole, and quadrupole transitions in He4 using realistic interactions. We benchmark the results with the hyperspherical harmonics method and show agreement within 2σ, where the uncertainties are estimated from the use of the many-body technique. We investigate the dependence of the results on three different interactions, including chiral potentials, and we report on the He4 electric dipole polarizability calculated in the SA-NCSM that …

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Multidimensional Molecular High-Harmonic Spectroscopy: A Road Map For Charge Migration Studies, Daniel R. Tuthill, François Mauger, Timothy D. Scarborough, Robert R. Jones, Mette B. Gaarde, Kenneth Lopata, Kenneth J. Schafer, Louis F. Dimauro Jul 2020

Multidimensional Molecular High-Harmonic Spectroscopy: A Road Map For Charge Migration Studies, Daniel R. Tuthill, François Mauger, Timothy D. Scarborough, Robert R. Jones, Mette B. Gaarde, Kenneth Lopata, Kenneth J. Schafer, Louis F. Dimauro

Faculty Publications

This review discusses recent experimental and theoretical analyses of high-harmonic spectroscopy in small molecules, with the aim of characterizing charge migration. We discuss the formulation of molecular high-harmonic spectra followed by methods to extract molecular-target-specific information, both in experiments and ab initio simulations. We present measured and simulated high-harmonic spectra from carbon dioxide and carbonyl sulfide to illustrate the necessity for multidimensional analyses for high-harmonic spectroscopies that include both the spectral amplitude and phase. Leveraging these results, we examine how such multidimensional analyses pave the way for the study of charge migration with high-harmonic spectroscopy and illustrate the beneficial role …

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Room-Temperature Optomechanical Squeezing, Nancy Aggarwal, Torrey J. Cullen, Jonathan Cripe, Garrett D. Cole, Robert Lanza, Adam Libson, David Follman, Paula Heu, Thomas Corbitt, Nergis Mavalvala Jul 2020

Room-Temperature Optomechanical Squeezing, Nancy Aggarwal, Torrey J. Cullen, Jonathan Cripe, Garrett D. Cole, Robert Lanza, Adam Libson, David Follman, Paula Heu, Thomas Corbitt, Nergis Mavalvala

Faculty Publications

Squeezed light—light with quantum noise lower than shot noise in some quadratures and higher in others—can be used to improve the sensitivity of precision measurements. In particular, squeezed light sources based on nonlinear optical crystals are being used to improve the sensitivity of gravitational wave detectors. In optomechanical squeezers, the radiation-pressure-driven interaction of a coherent light field with a mechanical oscillator induces correlations between the amplitude and phase quadratures of the light, which induce the squeezing. However, thermally driven fluctuations of the mechanical oscillator’s position make it difficult to observe the quantum correlations at room temperature and at low frequencies. …

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First Measurement Of The Charged Current Ν ¯ Μ Double Differential Cross Section On A Water Target Without Pions In The Final State First Measurement Of The Charged Current ... Abe K. Et Al., K. Abe, R. Akutsu, A. Ali, C. Alt, C. Andreopoulos, L. Anthony, M. Antonova, S. Aoki, A. Ariga, Y. Ashida, E. T. Atkin, Y. Awataguchi, S. Ban, M. Barbi, G. J. Barker, G. Barr, C. Barry, M. Batkiewicz-Kwasniak, A. Beloshapkin, F. Bench, V. Berardi, S. Berkman, L. Berns, S. Bhadra, S. Bienstock, A. Blondel, S. Bolognesi, B. Bourguille Jul 2020

First Measurement Of The Charged Current Ν ¯ Μ Double Differential Cross Section On A Water Target Without Pions In The Final State First Measurement Of The Charged Current ... Abe K. Et Al., K. Abe, R. Akutsu, A. Ali, C. Alt, C. Andreopoulos, L. Anthony, M. Antonova, S. Aoki, A. Ariga, Y. Ashida, E. T. Atkin, Y. Awataguchi, S. Ban, M. Barbi, G. J. Barker, G. Barr, C. Barry, M. Batkiewicz-Kwasniak, A. Beloshapkin, F. Bench, V. Berardi, S. Berkman, L. Berns, S. Bhadra, S. Bienstock, A. Blondel, S. Bolognesi, B. Bourguille

Faculty Publications

This paper reports the first differential measurement of the charged-current ν¯μ interaction cross section on water with no pions in the final state. The unfolded flux-averaged measurement using the T2K off-axis near detector is given in double-differential bins of μ+ momentum and angle. The integrated cross section in a restricted phase space is σ=(1.11±0.18)×10-38 cm2 per water molecule. Comparisons with several nuclear models are also presented.

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Comparison Of Chemotherapeutic Activities Of Rhodamine-Based Gumbos And Nanogumbos, Nimisha Bhattarai, Mi Chen, Rocío L. Pérez, Sudhir Ravula, Robert M. Strongin, Karen Mcdonough, Isiah M. Warner Jul 2020

Comparison Of Chemotherapeutic Activities Of Rhodamine-Based Gumbos And Nanogumbos, Nimisha Bhattarai, Mi Chen, Rocío L. Pérez, Sudhir Ravula, Robert M. Strongin, Karen Mcdonough, Isiah M. Warner

Faculty Publications

© 2020 by the authors. Rhodamine derivatives have been widely investigated for their mitochondrial targeting and chemotherapeutic properties that result from their lipophilic cationic structures. In previous research, we have found that conversion of Rhodamine 6G into nanoGUMBOS, i.e., nanomaterials derived from a group of uniform materials based on organic salts (GUMBOS), led to selective chemotherapeutic toxicity for cancer cells over normal cells. Herein, we investigate the chemotherapeutic activity of GUMBOS derived from four different rhodamine derivatives, two bearing an ester group, i.e., Rhodamine 123 (R123) and SNAFR-5, and two bearing a carboxylic acid group, i.e., rhodamine 110 (R110) and …

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Multidimensional Molecular High-Harmonic Spectroscopy: A Road Map For Charge Migration Studies, Daniel R. Tuthill, François Mauger, Timothy D. Scarborough, Robert R. Jones, Mette B. Gaarde, Kenneth Lopata, Kenneth J. Schafer, Louis F. Dimauro Jul 2020

Multidimensional Molecular High-Harmonic Spectroscopy: A Road Map For Charge Migration Studies, Daniel R. Tuthill, François Mauger, Timothy D. Scarborough, Robert R. Jones, Mette B. Gaarde, Kenneth Lopata, Kenneth J. Schafer, Louis F. Dimauro

Faculty Publications

© 2020 Elsevier Inc. This review discusses recent experimental and theoretical analyses of high-harmonic spectroscopy in small molecules, with the aim of characterizing charge migration. We discuss the formulation of molecular high-harmonic spectra followed by methods to extract molecular-target-specific information, both in experiments and ab initio simulations. We present measured and simulated high-harmonic spectra from carbon dioxide and carbonyl sulfide to illustrate the necessity for multidimensional analyses for high-harmonic spectroscopies that include both the spectral amplitude and phase. Leveraging these results, we examine how such multidimensional analyses pave the way for the study of charge migration with high-harmonic spectroscopy and …

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Sixty-First Supplement To The American Ornithological Society's Check-List Of North American Birds, R. Terry Chesser, Shawn M. Billerman, Kevin J. Burns, Carla Cicero, Jon L. Dunn, Andrew W. Kratter, Irby J. Lovette, Nicholas A. Mason, Pamela C. Rasmussen, J. V. Remsen, Douglas F. Stotz, Kevin Winker Jul 2020

Sixty-First Supplement To The American Ornithological Society's Check-List Of North American Birds, R. Terry Chesser, Shawn M. Billerman, Kevin J. Burns, Carla Cicero, Jon L. Dunn, Andrew W. Kratter, Irby J. Lovette, Nicholas A. Mason, Pamela C. Rasmussen, J. V. Remsen, Douglas F. Stotz, Kevin Winker

Faculty Publications

No abstract provided.

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Frequent Fire Slows Microbial Decomposition Of Newly Deposited Fine Fuels In A Pyrophilic Ecosystem, Jacob R. Hopkins, Jean M. Huffman, William J. Platt, Benjamin A. Sikes Jul 2020

Frequent Fire Slows Microbial Decomposition Of Newly Deposited Fine Fuels In A Pyrophilic Ecosystem, Jacob R. Hopkins, Jean M. Huffman, William J. Platt, Benjamin A. Sikes

Faculty Publications

© 2020, Springer-Verlag GmbH Germany, part of Springer Nature. Frequent fires maintain nearly 50% of terrestrial ecosystems, and drive ecosystem changes that govern future fires. Since fires are dependent on available plant or fine fuels, ecosystem processes that alter fine fuel loads like microbial decomposition are particularly important and could modify future fires. We hypothesized that variation in short-term fire history would influence fuel dynamics in such ecosystems. We predicted that frequent fires within a short-time period would slow microbial decomposition of new fine fuels. We expected that fire effects would differ based on dominant substrates and that fire history …

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Genotyping Xylella Fastidiosa In Rabbiteye Blueberry In Louisiana, Usa, Mary Helen Ferguson, Christopher A. Clark, Barbara J. Smith Jul 2020

Genotyping Xylella Fastidiosa In Rabbiteye Blueberry In Louisiana, Usa, Mary Helen Ferguson, Christopher A. Clark, Barbara J. Smith

Faculty Publications

Rabbiteye blueberry (Vaccinium ashei = V. virgatum) comprises much of the blueberry acreage in the southeastern USA states of Louisiana and Mississippi. Three genotypes of X. fastidiosa were identified from rabbiteye blueberry in Louisiana by multilocus sequence typing. A genotype that was found at two orchards, sequence type (ST) 42, was identical to one previously found in southern highbush blueberry in Georgia and two non-blueberry native species in Texas. Two newly identified genotypes shared most alleles with X. fastidiosa strains considered, like ST 42, to be part of a group that is believed to have resulted from recombination between X. …

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Adaptive Responses To Maternal Nutrient Restriction Alter Placental Transport In Ewes, Ashley K. Edwards, Sorin M. Mcknight, Katharine Askelson, Jason R. Mcknight, Kathrin A. Dunlap, M. Carey Satterfield Jul 2020

Adaptive Responses To Maternal Nutrient Restriction Alter Placental Transport In Ewes, Ashley K. Edwards, Sorin M. Mcknight, Katharine Askelson, Jason R. Mcknight, Kathrin A. Dunlap, M. Carey Satterfield

Faculty Publications

Introduction: Maternal nutrient partitioning, uteroplacental blood flow, transporter activity, and fetoplacental metabolism mediate nutrient delivery to the fetus. Inadequate availability or delivery of nutrients results in intrauterine growth restriction (IUGR), a leading cause of neonatal morbidity and mortality. Maternal nutrient restriction can result in IUGR, but only in an unforeseeable subset of individuals. Methods: To elucidate potential mechanisms regulating fetal nutrient availability, singleton sheep pregnancies were generated by embryo transfer. Pregnant ewes received either a 50% NRC (NR; n = 24) or 100% NRC (n = 7) diet from gestational Day 35 until necropsy on Day 125. Maternal weight did …

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Erratum: Small-Molecule Inhibitors Of Inward Rectifier Potassium (Kir) Channels Reduce Bloodmeal Feeding And Have Insecticidal Activity Against The Horn Fly (Diptera: Muscidae) (Journal Of Medical Entomology (2020) Doi: 10.1093/Jme/Tjaa015), Z. Li, F. Guerrero, A. A. Pérez De León, L. D. Foil, D. R. Swale Jul 2020

Erratum: Small-Molecule Inhibitors Of Inward Rectifier Potassium (Kir) Channels Reduce Bloodmeal Feeding And Have Insecticidal Activity Against The Horn Fly (Diptera: Muscidae) (Journal Of Medical Entomology (2020) Doi: 10.1093/Jme/Tjaa015), Z. Li, F. Guerrero, A. A. Pérez De León, L. D. Foil, D. R. Swale

Faculty Publications

Correction of "Li Z., F. Guerrero, A. A. Pérez de León, L. D. Foil, and D. R. Swale. 2020. Small-Molecule Inhibitors of Inward Rectifier Potassium (Kir) Channels Reduce Bloodmeal Feeding and Have Insecticidal Activity Against the Horn Fly (Diptera: Muscidae). J. Med. Entomol."DOI: 10.1093/jme/tjaa015. In the original version of this article, the chemical structure of ML297 in Figure 1 was incorrect. The figure has been updated to contain the correct structure. The authors regret the error. (Figure Presented).

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Mitochondrial Genomes And Thousands Of Ultraconserved Elements Resolve The Taxonomy And Historical Biogeography Of The Euphonia And Chlorophonia Finches (Passeriformes: Fringillidae), Tyler S. Imfeld, F. Keith Barker, Robb T. Brumfield Jul 2020

Mitochondrial Genomes And Thousands Of Ultraconserved Elements Resolve The Taxonomy And Historical Biogeography Of The Euphonia And Chlorophonia Finches (Passeriformes: Fringillidae), Tyler S. Imfeld, F. Keith Barker, Robb T. Brumfield

Faculty Publications

© 2020 American Ornithological Society. Relationships of the Neotropical finches in the genera Euphonia and Chlorophonia (Fringillidae: Euphoniinae) have been clarified by recent molecular studies, but species-level relationships within this group have not been thoroughly addressed. In this study, we sampled specimens representing every recognized species of these genera, in addition to 2 outgroup taxa, and used target enrichment to sequence thousands of ultraconserved element (UCE) loci, as well as mitochondrial DNA reconstructed from off-target reads, from each specimen to infer these relationships. We constructed both concatenation and coalescent-based estimates of phylogeny from this dataset using matrices of varying levels …

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Phylogeography Of The Variable Antshrike (Thamnophilus Caerulescens), A South American Passerine Distributed Along Multiple Environmental Gradients, Sergio D. Bolívar-Leguizamón, Luís F. Silveira, Elizabeth P. Derryberry, Robb T. Brumfield, Gustavo A. Bravo Jul 2020

Phylogeography Of The Variable Antshrike (Thamnophilus Caerulescens), A South American Passerine Distributed Along Multiple Environmental Gradients, Sergio D. Bolívar-Leguizamón, Luís F. Silveira, Elizabeth P. Derryberry, Robb T. Brumfield, Gustavo A. Bravo

Faculty Publications

© 2020 Elsevier Inc. The Neotropics show a wealth of distributional patterns shared by many co-distributed species. A distinctive pattern is the so-called “circum-Amazonian distribution,” which is observed in species that do not occur in Amazonia but rather along a belt of forested habitats spanning south and east of Amazonia, the Andean foothills, and often into the Venezuelan Coastal Range and the Tepuis. Although this pattern is widespread across animals and plants, its underlying biogeographic mechanisms remain poorly understood. The Variable Antshrike (Thamnophilus caerulescens) is a sexually dimorphic suboscine passerine that exhibits extreme plumage variation and occurs along the southern …

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Multigrid Methods For Saddle Point Problems: Optimality Systems, Susanne C. Brenner, Sijing Liu, Li Yeng Sung Jul 2020

Multigrid Methods For Saddle Point Problems: Optimality Systems, Susanne C. Brenner, Sijing Liu, Li Yeng Sung

Faculty Publications

We develop multigrid methods for an elliptic distributed optimal control problem on convex domains that are robust with respect to a regularization parameter. We prove the uniform convergence of the W-cycle algorithm and demonstrate the performance of V-cycle and W-cycle algorithms through numerical experiments.

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Sequential Predictors For Delay Compensation For Perturbed Discrete Time Systems, Frederic Mazenc, Michael Malisoff Jul 2020

Sequential Predictors For Delay Compensation For Perturbed Discrete Time Systems, Frederic Mazenc, Michael Malisoff

Faculty Publications

We provide sequential predictors for delayed time-varying discrete time linear systems with outputs, where the system and output measurements are perturbed by uncertainty. Our predictors ensure input-to-state stability with respect to uncertainties in the system and in the output, under arbitrarily long input delays. Our strategy is to introduce a number of dynamical extensions that equals the length of the input delay. Our example illustrates the usefulness of our control design.

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Sampled-Data Estimator For Nonlinear Systems With Arbitrarily Fast Rate Of Convergence, Frederic Mazenc, Michael Malisoff, Silviu Iulian Niculescu Jul 2020

Sampled-Data Estimator For Nonlinear Systems With Arbitrarily Fast Rate Of Convergence, Frederic Mazenc, Michael Malisoff, Silviu Iulian Niculescu

Faculty Publications

We study continuous-time nonlinear systems with discrete measurements. We provide an estimate of the state variable that converges with a rate of convergence that can be made arbitrarily large by reducing the size of the largest sampling interval. Our proof of the convergence result is based on a recently developed trajectory based approach.

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Mechanical Properties And Performance Under Laboratory And Field Conditions Of A Lightweight Fluorogypsum-Based Blend For Economic Artificial-Reef Construction, Yasser Bigdeli, Michele Barbato, Charles D. Lofton, Maria Teresa Gutierrez-Wing, Kelly A. Rusch Jul 2020

Mechanical Properties And Performance Under Laboratory And Field Conditions Of A Lightweight Fluorogypsum-Based Blend For Economic Artificial-Reef Construction, Yasser Bigdeli, Michele Barbato, Charles D. Lofton, Maria Teresa Gutierrez-Wing, Kelly A. Rusch

Faculty Publications

This paper investigates the mechanical properties under laboratory and field conditions of a concretelike blend made of fluorogypsum (FG), fly ash, and portland cement for artificial-reef construction, which is referred to as a FG-based blend. The 28-day compressive strength and relative volumetric expansion of the FG-based blend were statistically characterized. After 1 year of immersion in brackish water under field conditions, the compressive strength of the FG-based blend experienced a moderate reduction when compared with material under laboratory conditions but did not degrade below its 28-day value. Visual examination of the immersed specimens indicated that aquatic organisms are attracted to …

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