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Constitutive Models For Dynamic Strain Aging In Metals: Strain Rate And Temperature Dependences On The Flow Stress, Yooseob Song, Daniel Garcia-Gonzalez, Alexis Rusinek Apr 2020

Constitutive Models For Dynamic Strain Aging In Metals: Strain Rate And Temperature Dependences On The Flow Stress, Yooseob Song, Daniel Garcia-Gonzalez, Alexis Rusinek

Civil Engineering Faculty Publications

A new constitutive model for Q235B structural steel is proposed, incorporating the effect of dynamic strain aging. Dynamic strain aging hugely affects the microstructural behavior of metallic compounds, in turn leading to significant alterations in their macroscopic mechanical response. Therefore, a constitutive model must incorporate the effect of dynamic strain aging to accurately predict thermo-mechanical deformation processes. The proposed model assumes the overall response of the material as a combination of three contributions: athermal, thermally activated, and dynamic strain aging stress components. The dynamic strain aging is approached by two alternative mathematical expressions: (i) model I: rate-independent model; (ii) model …

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Optically Targeted Search For Gravitational Waves Emitted By Core-Collapse Supernovae During The First And Second Observing Runs Of Advanced Ligo And Advanced Virgo, B. P. Abbott, R. Abbott, T. D. Abbott, S. Abra, F. Acernese, K. Ackley, C. Adams, V. B. Adya, Teviet Creighton, Mario C. Diaz Apr 2020

Optically Targeted Search For Gravitational Waves Emitted By Core-Collapse Supernovae During The First And Second Observing Runs Of Advanced Ligo And Advanced Virgo, B. P. Abbott, R. Abbott, T. D. Abbott, S. Abra, F. Acernese, K. Ackley, C. Adams, V. B. Adya, Teviet Creighton, Mario C. Diaz

Physics & Astronomy Faculty Publications

We present the results from a search for gravitational-wave transients associated with core-collapse supernovae observed within a source distance of approximately 20 Mpc during the first and second observing runs of Advanced LIGO and Advanced Virgo. No significant gravitational-wave candidate was detected. We report the detection efficiencies as a function of the distance for waveforms derived from multidimensional numerical simulations and phenomenological extreme emission models. The sources with neutrino-driven explosions are detectable at the distances approaching 5 kpc, and for magnetorotationally driven explosions the distances are up to 54 kpc. However, waveforms for extreme emission models are detectable up to …

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The Simulated Biological Response To Southern Ocean Eddies Via Biological Rate Modification And Physical Transport, Tyler Rohr, Cheryl S. Harrison, Matthew C. Long, Peter Gaube, Scott C. Doney Apr 2020

The Simulated Biological Response To Southern Ocean Eddies Via Biological Rate Modification And Physical Transport, Tyler Rohr, Cheryl S. Harrison, Matthew C. Long, Peter Gaube, Scott C. Doney

School of Earth, Environmental, & Marine Sciences Faculty Publications

We examine the structure and drivers of anomalous phytoplankton biomass in Southern Ocean eddies tracked in a global, multiyear, eddy-resolving, 3-D ocean simulation of the Community Earth System Model.We examine how simulated anticyclones and cyclones differentially modify phytoplankton biomass concentrations, growth rates, and physical transport. On average, cyclones induce negative division rate anomalies that drive negative net population growth rate anomalies, reduce dilution across shallower mixed layers, and advect biomass anomalously downward via eddy-induced Ekman pumping. The opposite is true in anticyclones. Lateral transport is dominated by eddy stirring rather than eddy trapping. The net effect on anomalous biomass can …

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Perceptions And Opinions Of The Usability Of Simulations In A Mathematics Methods Course For Elementary Pre-Service Teachers, Jair J. Aguilar, James A. Telese Apr 2020

Perceptions And Opinions Of The Usability Of Simulations In A Mathematics Methods Course For Elementary Pre-Service Teachers, Jair J. Aguilar, James A. Telese

Teaching and Learning Faculty Publications

The acceptance and perceptions of a technology is relevant and pertinent because it would facilitate its adoption and integration (Jurison, 2000). In this regard, the integration of new technologies in education, and especially in teacher preparation programs, offer future teachers a variety of opportunities to be better prepared. Pre-service teacher’s perceptions, views, and opinions on how technology can help them acquire new knowledge and teaching skills, can be influenced if technologies are integrated, presented, and linked to the goals and objectives of the courses in a preparation program (Gordon, Brayshaw, & Grey, 2015; Russell, Bebell, O'Dwyer & O'Connor, 2003). For …

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Eddy-Modified Iron, Light, And Phytoplankton Cell Division Rates In The Simulated Southern Ocean, Tyler Rohr, Cheryl S. Harrison, Matthew C. Long, Peter Gaube, Scott C. Doney Apr 2020

Eddy-Modified Iron, Light, And Phytoplankton Cell Division Rates In The Simulated Southern Ocean, Tyler Rohr, Cheryl S. Harrison, Matthew C. Long, Peter Gaube, Scott C. Doney

School of Earth, Environmental, & Marine Sciences Faculty Publications

We examine the effects of Southern Ocean eddies on phytoplankton cell division rates in a global, multiyear, eddy‐resolving, 3‐D ocean simulation of the Community Earth System Model. We first identify and track eddies in the simulation and validate their distribution and demographics against observed eddy trajectory characteristics. Next, we examine how simulated cyclones and anticyclones differentially modify iron, light, and ultimately population‐specific cell division rates. We use an eddy‐centric, depth‐averaged framework to explicitly examine the dynamics of the phytoplankton population across the entire water column within an eddy. We find that population‐averaged iron availability is elevated in anticyclones throughout the …

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1h, 13c And 15n Resonance Assignments Of Translation Initiation Factor 3 From Pseudomonas Aeruginosa, Libo Li, Stephanie O. Palmer, Elizabeth A. Gomez, Frank Mendiola, Tianzhi Wang, James M. Bullard, Yonghong Zhang Apr 2020

1h, 13c And 15n Resonance Assignments Of Translation Initiation Factor 3 From Pseudomonas Aeruginosa, Libo Li, Stephanie O. Palmer, Elizabeth A. Gomez, Frank Mendiola, Tianzhi Wang, James M. Bullard, Yonghong Zhang

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Translation initiation factor 3 (IF3) is one of the three protein factors that bind to the small ribosomal subunit and it is required for the initiation of protein biosynthesis in bacteria. IF3 contains two independent domains, N- and C-terminal domains, which are connected by a lysine-rich interdomain linker. IF3 undergoes large-scale movements and conformational changes upon binding to the 30S subunit and also during the functional regulation of initiation. However, the precise dynamic interplay of the two domains and the molecular mechanism of IF3 is not well understood. A high-resolution 3D structure of a complete IF3 in bacteria has not …

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Glutaminyl-Trna Synthetase From Pseudomonas Aeruginosa: Characterization, Structure, And Development As A Screening Platform, Yaritza Escamilla, Casey A. Hughes, Jan Abendroth, David M. Dranow, Samantha Balboa, Frank B. Dean, James M. Bullard Apr 2020

Glutaminyl-Trna Synthetase From Pseudomonas Aeruginosa: Characterization, Structure, And Development As A Screening Platform, Yaritza Escamilla, Casey A. Hughes, Jan Abendroth, David M. Dranow, Samantha Balboa, Frank B. Dean, James M. Bullard

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Pseudomonas aeruginosa has a high potential for developing resistance to multiple antibiotics. The gene (glnS) encoding glutaminyl-tRNA synthetase (GlnRS) from P. aeruginosa was cloned and the resulting protein characterized. GlnRS was kinetically evaluated and the KM and kcatobs , governing interactions with tRNA, were 1.0 μM and 0.15 s-1 , respectively. The crystal structure of the α2 form of P. aeruginosa GlnRS was solved to 1.9 Å resolution. The amino acid sequence and structure of P. aeruginosa GlnRS were analyzed and compared to that of GlnRS from Escherichia coli. Amino acids that interact with ATP, glutamine, and tRNA are well …

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Toros Optical Follow-Up Of The Advanced Ligo–Virgo O2 Second Observational Campaign, Rodolfo Artola, Martin Beroiz, Juan Cabral, R. Camuccio, Moises Castillo, Mario C. Diaz, Aldo Fonrouge, Alejandro F. Hinojosa, Andrea Hinojosa, Americo F. Hinojosa, Lucas M. Macri Apr 2020

Toros Optical Follow-Up Of The Advanced Ligo–Virgo O2 Second Observational Campaign, Rodolfo Artola, Martin Beroiz, Juan Cabral, R. Camuccio, Moises Castillo, Mario C. Diaz, Aldo Fonrouge, Alejandro F. Hinojosa, Andrea Hinojosa, Americo F. Hinojosa, Lucas M. Macri

Physics & Astronomy Faculty Publications

We present themethods and results of the optical follow-up, conducted by the Transient Optical Robotic Observatory of the South Collaboration, of gravitational wave events detected during the Advanced LIGO–Virgo second observing run (2016 November–2017 August). Given the limited field of view (∼100 arcmin) of our observational instrumentation, we targeted galaxies within the area of high localization probability that were observable from our sites. We analysed the observations using difference imaging, followed by a random forest algorithm to discriminate between real and spurious transients. Our observations were conducted using telescopes at Estacion Astrofısica de Bosque Alegre, Cerro Tololo Inter-American Observatory, the …

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Towards A Real-Time Fully-Coherent All-Sky Search For Gravitational Waves From Compact Binary Coalescences Using Particle Swarm Optimization, Marc E. Normandin, Soumya Mohanty Apr 2020

Towards A Real-Time Fully-Coherent All-Sky Search For Gravitational Waves From Compact Binary Coalescences Using Particle Swarm Optimization, Marc E. Normandin, Soumya Mohanty

Physics & Astronomy Faculty Publications

While a fully-coherent all-sky search is known to be optimal for detecting gravitational wave signals from compact binary coalescences, its high computational cost has limited current searches to less sensitive coincidence-based schemes. Following up on previous work that has demonstrated the effectiveness of particle swarm optimization (PSO) in reducing the computational cost of this search, we present an implementation that achieves near real-time computational speed. This is achieved by combining the search efficiency of PSO with a significantly revised and optimized numerical implementation of the underlying mathematical formalism along with additional multithreaded parallelization layers in a distributed computing framework. For …

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Towards Precision Medicine: Defining And Characterizing Adipose Tissue Dysfunction To Identify Early Immunometabolic Risk In Symptom-Free Adults From The Gemm Family Study, Ernesto Rodriguez-Ayala, Esther C. Gallegos-Cabrales, Laura Gonzalez-Lopez, Hugo A. Laviada-Molina, Rocio A. Salinas-Osornio, Edna J. Nava-Gonzalez, Irene Leal-Berumen, Claudia Escudero-Lourdes, Fabiola Escalante-Araiza, Juan Carlos Lopez Alvarenga Apr 2020

Towards Precision Medicine: Defining And Characterizing Adipose Tissue Dysfunction To Identify Early Immunometabolic Risk In Symptom-Free Adults From The Gemm Family Study, Ernesto Rodriguez-Ayala, Esther C. Gallegos-Cabrales, Laura Gonzalez-Lopez, Hugo A. Laviada-Molina, Rocio A. Salinas-Osornio, Edna J. Nava-Gonzalez, Irene Leal-Berumen, Claudia Escudero-Lourdes, Fabiola Escalante-Araiza, Juan Carlos Lopez Alvarenga

School of Medicine Publications

Interactions between macrophages and adipocytes are early molecular factors influencing adipose tissue (AT) dysfunction, resulting in high leptin, low adiponectin circulating levels and low-grade metaflammation, leading to insulin resistance (IR) with increased cardiovascular risk. We report the characterization of AT dysfunction through measurements of the adiponectin/leptin ratio (ALR), the adipo-insulin resistance index (Adipo-IRi), fasting/postprandial (F/P) immunometabolic phenotyping and direct F/P differential gene expression in AT biopsies obtained from symptom-free adults from the GEMM family study. AT dysfunction was evaluated through associations of the ALR with F/P insulin-glucose axis, lipid-lipoprotein metabolism, and inflammatory markers. A relevant pattern of negative associations between …

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A (2+1)-Dimensional Sine-Gordon And Sinh-Gordon Equations With Symmetries And Kink Wave Solutions, Gangwei Wang, Kaitong Yang, Haicheng Gu, Fei Guan, A. H. Kara Apr 2020

A (2+1)-Dimensional Sine-Gordon And Sinh-Gordon Equations With Symmetries And Kink Wave Solutions, Gangwei Wang, Kaitong Yang, Haicheng Gu, Fei Guan, A. H. Kara

School of Mathematical & Statistical Sciences Faculty Publications

In this paper, a (2+1)-dimensional sine-Gordon equation and a sinh-Gordon equation are derived from the well-known AKNS system. Based on the Hirota bilinear method and Lie symmetry analysis, kink wave solutions and travelingwave solutions of the (2+1)-dimensional sine-Gordon equation are constructed. The traveling wave solutions of the (2+1)-dimensional sinh-Gordon equation can also be provided in a similar manner. Meanwhile, conservation laws are derived.

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The Global Existence Of Small Self-Interacting Scalar Field Propagating In The Contracting Universe, Anahit Galstian, Karen Yagdjian Apr 2020

The Global Existence Of Small Self-Interacting Scalar Field Propagating In The Contracting Universe, Anahit Galstian, Karen Yagdjian

School of Mathematical & Statistical Sciences Faculty Publications

We present a condition on the self-interaction term that guaranties the existence of the global in time solution of the Cauchy problem for the semilinear Klein-Gordon equation in the Friedmann-Lamaˆitre-Robertson-Walker model of the contracting universe. For the Klein- Gordon equation with the Higgs potential we give a lower estimate for the lifespan of solution.

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Analysis Of The Healthcare Mers-Cov Outbreak In King Abdulaziz Medical Center, Riyadh, Saudi Arabia, June–August 2015 Using A Seir Ward Transmission Model, Tamer Oraby, Michael G. Tyshenko, Hanan H. Balkhy, Yasar Tasnif, Adriana Quiroz-Gaspar, Zeinab Mohamed, Ayesha Araya, Susie Elsaadany, Eman Al-Mazroa, Mohammed A. Alhelail Apr 2020

Analysis Of The Healthcare Mers-Cov Outbreak In King Abdulaziz Medical Center, Riyadh, Saudi Arabia, June–August 2015 Using A Seir Ward Transmission Model, Tamer Oraby, Michael G. Tyshenko, Hanan H. Balkhy, Yasar Tasnif, Adriana Quiroz-Gaspar, Zeinab Mohamed, Ayesha Araya, Susie Elsaadany, Eman Al-Mazroa, Mohammed A. Alhelail

School of Mathematical & Statistical Sciences Faculty Publications

Middle East respiratory syndrome coronavirus (MERS-CoV) is an emerging zoonotic coronavirus that has a tendency to cause significant healthcare outbreaks among patients with serious comorbidities. We analyzed hospital data from the MERS-CoV outbreak in King Abdulaziz Medical Center, Riyadh, Saudi Arabia, June–August 2015 using the susceptible-exposed-infectious-recovered (SEIR) ward transmission model. The SEIR compartmental model considers several areas within the hospital where transmission occurred. We use a system of ordinary differential equations that incorporates the following units: emergency department (ED), out-patient clinic, intensive care unit, and hospital wards, where each area has its own carrying capacity and distinguishes the transmission by …

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Soil Biotic And Abiotic Conditions Negate Invasive Species Performance In Native Habitat, Pushpa Soti, Matthew Purcell, Krish Jayachandran Apr 2020

Soil Biotic And Abiotic Conditions Negate Invasive Species Performance In Native Habitat, Pushpa Soti, Matthew Purcell, Krish Jayachandran

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Background: Most studies on plant invasion consider the enemy release hypothesis when analyzing native habitats. However, the lower performance of invasive species in the native habitats can be the result of unfavorable soil conditions in the native habitats. While soil biotic and abiotic factors have a potential to restrict the growth of invasive species in their native habitats, our understanding of belowground environment of invasive species in their native habitats is very limited. In this study, we analyzed soil characteristics associated with an exotic invasive plant, Old World Climbing Fern (Lygodium microphyllum), in its native habitat in Australia and the …

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Ramanujan’S Theorem And Highest Abundant Numbers, Oleg R. Musin Apr 2020

Ramanujan’S Theorem And Highest Abundant Numbers, Oleg R. Musin

School of Mathematical & Statistical Sciences Faculty Publications

In 1915, Ramanujan proved asymptotic inequalities for the sum of divisors function, assuming the Riemann hypothesis (RH). We consider a strong version of Ramanujan’s theorem and define highest abundant numbers that are extreme with respect to the Ramanujan and Robin inequalities. Properties of these numbers are very different depending on whether the RH is true or false.

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Versatile Bismuth Salts-Induced Reactions From Our Laboratory: A Perspective, Debasish Bandyopadhyay, Bimal Krishna Banik Apr 2020

Versatile Bismuth Salts-Induced Reactions From Our Laboratory: A Perspective, Debasish Bandyopadhyay, Bimal Krishna Banik

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Bismuth salts-mediated reactions are developed for the synthesis of diverse organic molecules of medicinal significance. Reactions conducted with bismuth salts are environmentally friendly and these may proceed due to the release of acids in the media. Bismuth salt may also act as a Lewis acid in these reactions. Versatile organic molecules in chiral and achiral forms are synthesized using bismuth salts-induced reactions at our research laboratory.

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Structure–Activity Relationship Of Rgd-Containing Cyclic Octapeptide And Αvβ3 Integrin Allows For Rapid Identification Of A New Peptide Antagonist, Aaron Silva, Wenwu Xiao, Yan Wang, Wei Wang, Heng Wei Chang, James B. Ames, Kit S. Lam, Yonghong Zhang Apr 2020

Structure–Activity Relationship Of Rgd-Containing Cyclic Octapeptide And Αvβ3 Integrin Allows For Rapid Identification Of A New Peptide Antagonist, Aaron Silva, Wenwu Xiao, Yan Wang, Wei Wang, Heng Wei Chang, James B. Ames, Kit S. Lam, Yonghong Zhang

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

The αvβ3 integrin, a receptor for many extracellular matrix proteins with RGD-sequence motif, is involved in multiple physiological processes and highly expressed in tumor cells, therefore making it a target for cancer therapy and tumor imaging. Several RGD-containing cyclic octapeptide (named LXW analogs) were screened as αvβ3 antagonists with dramatically different binding affinity, and their structure–activity relationship (SAR) remains elusive. We performed systematic SAR studies and optimized LXW analogs to improve antagonistic potency. The NMR structure of LXW64 was determined and docked to the integrin. Structural comparison and docking studies suggested that the hydrophobicity and aromaticity of the X7 amino …

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Gw190425: Observation Of A Compact Binary Coalescence With Total Mass ∼ 3.4 M⊙, B. P. Abbott, R. Abbott, T. D. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Satzhan Sitmukhambetov, Wenhui Wang Mar 2020

Gw190425: Observation Of A Compact Binary Coalescence With Total Mass ∼ 3.4 M⊙, B. P. Abbott, R. Abbott, T. D. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Satzhan Sitmukhambetov, Wenhui Wang

Physics & Astronomy Faculty Publications

On 2019 April 25, the LIGO Livingston detector observed a compact binary coalescence with signal-to-noise ratio 12.9. The Virgo detector was also taking data that did not contribute to detection due to a low signal-to-noise ratio, but were used for subsequent parameter estimation. The 90% credible intervals for the component masses range from to (– if we restrict the dimensionless component spin magnitudes to be smaller than 0.05). These mass parameters are consistent with the individual binary components being neutron stars. However, both the source-frame chirp mass and the total mass of this system are significantly larger than those of …

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The Genetic Architecture Of The Human Cerebral Cortex, Katrina L. Grasby, Neda Jahanshad, Jodie N. Painter, Lucia Colodro-Conde, Janita Bralten, Derrek P. Hibar, Penelope A. Lind, Fabrizio Pizzagalli, Marcio A. Almeida, Joanne E. Curran, John Blangero Mar 2020

The Genetic Architecture Of The Human Cerebral Cortex, Katrina L. Grasby, Neda Jahanshad, Jodie N. Painter, Lucia Colodro-Conde, Janita Bralten, Derrek P. Hibar, Penelope A. Lind, Fabrizio Pizzagalli, Marcio A. Almeida, Joanne E. Curran, John Blangero

School of Medicine Publications

The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area …

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Integer Versus Fractional Order Seir Deterministic And Stochastic Models Of Measles, Md Rafiul Islam, Angela Peace, Daniel Medina, Tamer Oraby Mar 2020

Integer Versus Fractional Order Seir Deterministic And Stochastic Models Of Measles, Md Rafiul Islam, Angela Peace, Daniel Medina, Tamer Oraby

School of Mathematical & Statistical Sciences Faculty Publications

In this paper, we compare the performance between systems of ordinary and (Caputo) fractional differential equations depicting the susceptible-exposed-infectious-recovered (SEIR) models of diseases. In order to understand the origins of both approaches as mean-field approximations of integer and fractional stochastic processes, we introduce the fractional differential equations (FDEs) as approximations of some type of fractional nonlinear birth and death processes. Then, we examine validity of the two approaches against empirical courses of epidemics; we fit both of them to case counts of three measles epidemics that occurred during the pre-vaccination era in three different locations. While ordinary differential equations (ODEs) …

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Loop-Closure Kinetics Reveal A Stable, Right-Handed Dna Intermediate In Cre Recombination, Massa J. Shoura, Stefan M. Giovan, Alexandre A. Vetcher, Riccardo Ziraldo, Andreas Hanke, Stephen D. Levene Mar 2020

Loop-Closure Kinetics Reveal A Stable, Right-Handed Dna Intermediate In Cre Recombination, Massa J. Shoura, Stefan M. Giovan, Alexandre A. Vetcher, Riccardo Ziraldo, Andreas Hanke, Stephen D. Levene

Physics & Astronomy Faculty Publications

In Cre site-specific recombination, the synaptic intermediate is a recombinase homotetramer containing a pair of loxP DNA target sites. The enzyme system's strand-exchange mechanism proceeds via a Holliday-junction (HJ) intermediate; however, the geometry of DNA segments in the synapse has remained highly controversial. In particular, all crystallographic structures are consistent with an achiral, planar Holliday-junction (HJ) structure, whereas topological assays based on Cre-mediated knotting of plasmid DNAs are consistent with a right-handed chiral junction. We use the kinetics of loop closure involving closely spaced (131–151 bp) loxP sites to investigate the in-aqueo ensemble of conformations for the longest-lived looped DNA …

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Political Design Meets Policy Complexity, Roland Pongou, Jean-Baptiste Tondji Mar 2020

Political Design Meets Policy Complexity, Roland Pongou, Jean-Baptiste Tondji

School of Economics and Finance Faculty Publications

The rules that are employed to pass policies in legislative bodies vary widely. It is generally argued that policies that differ in complexity or importance level should be decided under different kinds of voting rules. While this question has been examined for static legislative mechanisms, an analysis of the precise relationship between the level of policy complexity and the type of voting rule is still missing for dynamic mechanisms. We address this problem from the perspective of a preference-blind political designer. Given the level of complexity of the decision that is to be made, the political designer's goal is to …

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The Rider (2020-03-16), Victor G. Ramirez Mar 2020

The Rider (2020-03-16), Victor G. Ramirez

The Rider Archives

Vol.5 No.23

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On Persistence Of Superoscillations For Schrödinger Equation With Time-Dependent Quadratic Hamiltonians, Elijah Lee Hight, Jose Palacio, Tamer Oraby, Erwin Suazo Mar 2020

On Persistence Of Superoscillations For Schrödinger Equation With Time-Dependent Quadratic Hamiltonians, Elijah Lee Hight, Jose Palacio, Tamer Oraby, Erwin Suazo

School of Mathematical & Statistical Sciences Faculty Publications

In this work, we prove the persistence in time of superoscillations for the Schrödinger equation with time-dependent coefficients. In order to prove the persistence of superoscillations, we have conditioned the coefficients to satisfy a Riccati system, and we have expressed the solution as a convolution operator in terms of solutions of this Riccati system. Further, we have solved explicitly the Cauchy initial value problem with three different kinds of superoscillatory initial data. The operator is defined on a space of entire functions. Particular examples include Caldirola-Kanai and degenerate parametric harmonic oscillator Hamiltonians, and other examples could include Hamiltonians not self-adjoint. …

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Phylogeography Of Acartia Tonsa Dana, 1849 (Calanoida: Copepoda) And Phylogenetic Reconstruction Of The Genus Acartia Dana, 1846, Nicole J. Figueroa, Diego F. Figueroa, David Hicks Mar 2020

Phylogeography Of Acartia Tonsa Dana, 1849 (Calanoida: Copepoda) And Phylogenetic Reconstruction Of The Genus Acartia Dana, 1846, Nicole J. Figueroa, Diego F. Figueroa, David Hicks

School of Earth, Environmental, & Marine Sciences Faculty Publications

The calanoid copepod, Acartia tonsa Dana, 1849 is one of the most abundant and well-studied estuarian species with a worldwide distribution. In this research, we use the mitochondrial cytochrome oxidase subunit I gene to study the phylogeography of A. tonsa by analyzing sequences from specimens collected in the western Gulf of Mexico (GOM) along with all sequences from previous research. We reconstruct the phylogeny for the genus Acartia Dana, 1846 and highlight numerous potential misidentifications of Acartia species deposited in GenBank. The incorrect taxonomy assigned to some of these sequences results in apparently paraphyletic relationships. This study demonstrates that A. …

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Introductory Chapter: Dynamical Symmetries And Quantum Chaos, Paul Bracken Mar 2020

Introductory Chapter: Dynamical Symmetries And Quantum Chaos, Paul Bracken

School of Mathematical & Statistical Sciences Faculty Publications

No abstract provided.

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Daily Incentive And Jump-Base In A Non-Real-Time Apparel Manufacturing Context, Robert Dean Morrison, Juan Angel Chavarria, Claudia P. Dole, Brenda M. Dole Mar 2020

Daily Incentive And Jump-Base In A Non-Real-Time Apparel Manufacturing Context, Robert Dean Morrison, Juan Angel Chavarria, Claudia P. Dole, Brenda M. Dole

School of Accountancy Faculty Publications

This study summarizes piecework incentive systems and examines two apparel manufacturing factories that used daily incentive calculations at one time and weekly incentive calculations at another. In addition, one factory implemented a multiple base-rate incentive system, often called jump-base. The data shows that, when not controlled, daily incentive can facilitate operators engaging in fraudulent activity such as ticket-holding. With fraud controlled, daily incentive calculation makes little difference in overall pay; therefore, it may have individual level motivational effects by nullifying the effect of averaging one-bad-day into the week. While jump-base may enhance productivity in lower performing operators or modules, one …

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Application Of Acoustical Remote Sensing Techniques For Ecosystem Monitoring Of A Seagrass Meadow, Megan S. Ballard, Kevin M. Lee, Jason D. Sagers, Gabriel R. Venegas, Andrew R. Mcneese, Preston S. Wilson, Abdullah Rahman Mar 2020

Application Of Acoustical Remote Sensing Techniques For Ecosystem Monitoring Of A Seagrass Meadow, Megan S. Ballard, Kevin M. Lee, Jason D. Sagers, Gabriel R. Venegas, Andrew R. Mcneese, Preston S. Wilson, Abdullah Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

Seagrasses provide a multitude of ecosystem services and serve as important organic carbon stores. However, seagrass habitats are declining worldwide, threatened by global climate change and regional shifts in water quality. Acoustical methods have been applied to assess changes in oxygen production of seagrass meadows since sound propagation is sensitive to the presence of bubbles, which exist both within the plant tissue and freely floating the water as byproducts of photosynthesis. This work applies acoustic remote sensing techniques to characterize two different regions of a seagrass meadow: a densely vegetated meadow of Thalassia testudinum and a sandy region sparsely populated …

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Subsea 2019 Expedition To The Gorda Ridge, Darlene S. S. Lim, Nicole A. Raineault, John A. Breier, Eric W. Chan, Josh Chernov, Tamar Cohen, Matthew Deans, Angela Garcia, Christopher R. German, Michelle Hauer Mar 2020

Subsea 2019 Expedition To The Gorda Ridge, Darlene S. S. Lim, Nicole A. Raineault, John A. Breier, Eric W. Chan, Josh Chernov, Tamar Cohen, Matthew Deans, Angela Garcia, Christopher R. German, Michelle Hauer

School of Earth, Environmental, & Marine Sciences Faculty Publications

The SUBSEA (Systematic Underwater Biogeochemical Science and Exploration Analog) program blends ocean exploration with “ocean worlds” research, along with NASA analog and work studies research, to address science, science operations, and technology knowledge gaps related to the exploration of our solar system. The science group researches venting fluids at isolated seamounts and spreading ridges in the Pacific Ocean as analog environments to putative volcanically hosted hydrothermal systems on other “ocean worlds” (defined as places in the outer solar system that could possess subsurface oceans). The science operations research group studies E/V Nautilus architecture, distributed teams, communication, and lowlatency telerobotics. The …

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Gram Determinant Solutions To Nonlocal Integrable Discrete Nonlinear Schrödinger Equations Via The Pair Reduction, Junchao Chen, Bao-Feng Feng, Yongyang Jin Mar 2020

Gram Determinant Solutions To Nonlocal Integrable Discrete Nonlinear Schrödinger Equations Via The Pair Reduction, Junchao Chen, Bao-Feng Feng, Yongyang Jin

School of Mathematical & Statistical Sciences Faculty Publications

In this paper, Gram determinant solutions of local and nonlocal integrable discrete nonlinear Schrödinger (IDNLS) equations are studied via the pair reduction. A generalized IDNLS equation is firstly introduced which possesses the single Casorati determinant solution. Two kinds of Gram determinant solutions are presented from Casorati determinant ones due to the gauge freedom. The different pair constraint conditions for wave numbers are imposed and then solutions of local and nonlocal IDNLS equations are derived in terms of Gram determinant.

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