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Initial Investigation Of Seasonal Flammability Of Three Invasive East Texas Forest Understory Fuels Using Thermogravimetric Analysis, Mike Tiller, Brian P. Oswald, Alyx Frantzen, Warren Conway, Ikuai Hung Jul 2020

Initial Investigation Of Seasonal Flammability Of Three Invasive East Texas Forest Understory Fuels Using Thermogravimetric Analysis, Mike Tiller, Brian P. Oswald, Alyx Frantzen, Warren Conway, Ikuai Hung

Faculty Publications

East Texas forest understory fuels have become increasingly infested with invasive species which have contributed to greater hazardous fuel loads when combined with decades of fire exclusion and passive management. This study focused on estimating seasonal changes in flammability parameters of invasive yaupon (Ilex vomitoria), Chinese privet (Ligustrum sinense), and Chinese tallow (Triadica sebifera) using thermogravimetric analysis. Foliage and stem samples were collected in the dormant (February) and growing (August) seasons. Differential thermogravimetric (DTG) and proximate analyses were used to estimate species specific flammability parameters related to relative spontaneous ignition temperature (RSIT), gas-phase maximum …

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Detecting Fitness Epistasis In Recently Admixed Populations With Genome-Wide Data, Xumin Ni, Mengshi Zhou, Heming Wang, Karen Y. He, Uli Broeckel, Craig Hanis, Sharon Kardia, Susan Redline, Richard S. Cooper, Hua Tang, Xiaofeng Zhu Jul 2020

Detecting Fitness Epistasis In Recently Admixed Populations With Genome-Wide Data, Xumin Ni, Mengshi Zhou, Heming Wang, Karen Y. He, Uli Broeckel, Craig Hanis, Sharon Kardia, Susan Redline, Richard S. Cooper, Hua Tang, Xiaofeng Zhu

Faculty Publications

Background: Fitness epistasis, the interaction effect of genes at different loci on fitness, makes an important contribution to adaptive evolution. Although fitness interaction evidence has been observed in model organisms, it is more difficult to detect and remains poorly understood in human populations as a result of limited statistical power and experimental constraints. Fitness epistasis is inferred from non-independence between unlinked loci. We previously observed ancestral block correlation between chromosomes 4 and 6 in African Americans. The same approach fails when examining ancestral blocks on the same chromosome due to the strong confounding effect observed in a recently admixed population. …

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All-Sky Search For Short Gravitational-Wave Bursts In The Second Advanced Ligo And Advanced Virgo Run, Tiffany Summerscales, Ligo Scientific Collaboration And The Virgo Collaboration Jul 2020

All-Sky Search For Short Gravitational-Wave Bursts In The Second Advanced Ligo And Advanced Virgo Run, Tiffany Summerscales, Ligo Scientific Collaboration And The Virgo Collaboration

Faculty Publications

We present the results of a search for short-duration gravitational-wave transients in the data from the second observing run of Advanced LIGO and Advanced Virgo. We search for gravitational-wave transients with a duration of milliseconds to approximately one second in the 32–4096 Hz frequency band with minimal assumptions about the signal properties, thus targeting a wide variety of sources. We also perform a matched-filter search for gravitational-wave transients from cosmic string cusps for which the waveform is well modeled. The unmodeled search detected gravitational waves from several binary black hole mergers which have been identified by previous analyses. No other …

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Hurricane Disturbance Stimulated Nitrification And Altered Ammonia Oxidizer Community Structure In Lake Okeechobee And St. Lucie Estuary (Florida), Justyna J. Hampel, Mark J. Mccarthy, Sanni L. Aalto, Silvia E. Newell Jul 2020

Hurricane Disturbance Stimulated Nitrification And Altered Ammonia Oxidizer Community Structure In Lake Okeechobee And St. Lucie Estuary (Florida), Justyna J. Hampel, Mark J. Mccarthy, Sanni L. Aalto, Silvia E. Newell

Faculty Publications

© Copyright © 2020 Hampel, McCarthy, Aalto and Newell. Nitrification is an important biological link between oxidized and reduced forms of nitrogen (N). The efficiency of nitrification plays a key role in mitigating excess N in eutrophic systems, including those with cyanobacterial harmful algal blooms (cyanoHABs), since it can be closely coupled with denitrification and removal of excess N. Recent work suggests that competition for ammonium (NH4+) between ammonia oxidizers and cyanoHABs can help determine microbial community structure. Nitrification rates and ammonia-oxidizing archaeal (AOA) and bacterial (AOB) community composition and gene abundances were quantified in Lake Okeechobee …

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Extensive Morphological Variability In Asexually Produced Planktic Foraminifera, Catherine V. Davis, Caitlin M. Livsey, Hannah M. Palmer, Pincelli M. Hull, Ellen Thomas, Tessa M. Hill, Claudia R. Benitez-Nelson Jul 2020

Extensive Morphological Variability In Asexually Produced Planktic Foraminifera, Catherine V. Davis, Caitlin M. Livsey, Hannah M. Palmer, Pincelli M. Hull, Ellen Thomas, Tessa M. Hill, Claudia R. Benitez-Nelson

Faculty Publications

Marine protists are integral to the structure and function of pelagic ecosystems and marine carbon cycling, with rhizarian biomass alone accounting for more than half of all mesozooplankton in the oligotrophic oceans. Yet, understanding how their environment shapes diversity within species and across taxa is limited by a paucity of observations of heritability and life history. Here, we present observations of asexual reproduction, morphologic plasticity, and ontogeny in the planktic foraminifer in laboratory culture. Our results demonstrate that planktic foraminifera reproduce both sexually and asexually and demonstrate extensive phenotypic plasticity in response to nonheritable factors. These two processes fundamentally explain …

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Decomposability Of Soil Organic Matter Over Time: The Soil Incubation Database (Sidb, Version 1.0) And Guidance For Incubation Procedures, Christina Schadel, Jeffrey Beem-Miller, Mina Aziz Rad, Susan E. Crow, Caitlin E. Hicks Pries, Jessica G. Ernakovich, Alison M. Hoyt, Alain Plante, Shane Stoner, Claire C. Treat, Carlos A. Sierra Jul 2020

Decomposability Of Soil Organic Matter Over Time: The Soil Incubation Database (Sidb, Version 1.0) And Guidance For Incubation Procedures, Christina Schadel, Jeffrey Beem-Miller, Mina Aziz Rad, Susan E. Crow, Caitlin E. Hicks Pries, Jessica G. Ernakovich, Alison M. Hoyt, Alain Plante, Shane Stoner, Claire C. Treat, Carlos A. Sierra

Faculty Publications

The magnitude of carbon (C) loss to the atmosphere via microbial decomposition is a function of the amount of C stored in soils, the quality of the organic matter, and physical, chemical, and biological factors that comprise the environment for decomposition. The decomposability of C is commonly assessed by laboratory soil incubation studies that measure greenhouse gases mineralized from soils under controlled conditions. Here, we introduce the Soil Incubation Database (SIDb) version 1.0, a compilation of time series data from incubations, structured into a new, publicly available, open-access database of C flux (carbon dioxide, CO2, or methane, CH4). In addition, …

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Automated 3d Reconstruction Using Optimized View-Planning Algorithms For Iterative Development Of Structure-From-Motion Models, Samuel Arce, Cory Vernon, Joshua Hammond, Valerie Newell, Joseph Janson, Kevin Franke, John Hedengren Jul 2020

Automated 3d Reconstruction Using Optimized View-Planning Algorithms For Iterative Development Of Structure-From-Motion Models, Samuel Arce, Cory Vernon, Joshua Hammond, Valerie Newell, Joseph Janson, Kevin Franke, John Hedengren

Faculty Publications

Unsupervised machine learning algorithms (clustering, genetic, and principal component analysis) automate Unmanned Aerial Vehicle (UAV) missions as well as the creation and refinement of iterative 3D photogrammetric models with a next best view (NBV) approach. The novel approach uses Structure-from-Motion (SfM) to achieve convergence to a specified orthomosaic resolution by identifying edges in the point cloud and planning cameras that “view” the holes identified by edges without requiring an initial model. This iterative UAV photogrammetric method successfully runs in various Microsoft AirSim environments. Simulated ground sampling distance (GSD) of models reaches as low as 3.4 cm per pixel, and generally, …

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Applications Of Open Innovation To The Supply Chain System In The Smes, Taeho Park, Tianqin Shi, Ming Zhou, Shu Zhou Jul 2020

Applications Of Open Innovation To The Supply Chain System In The Smes, Taeho Park, Tianqin Shi, Ming Zhou, Shu Zhou

Faculty Publications

The close-knitted structure of a supply chain seems to leave no room for the word 'open'. Closeness builds trust, enables information sharing, benefits transportation and more. Somehow, openness started to benefit supply chain management recently, through a trend called 'open innovation'. Based on gathered anecdotes and our interviews of industry professionals, we attempted to present a more complete picture of open innovation in supply chain management, including its potential benefits, major concerns, adoption hurdles, and future solutions. Our findings identified current perceptions of supply chain practitioners on open innovation and major hurdles and difficulties of implementing open innovation in supply …

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Shake Slice And Shake Concordant Links, Anthony Bosman Jul 2020

Shake Slice And Shake Concordant Links, Anthony Bosman

Faculty Publications

© 2020 World Scientific Publishing Company. We can construct a 4-manifold by attaching 2-handles to a 4-ball with framing r along the components of a link in the boundary of the 4-ball. We define a link as r-shake slice if there exists embedded spheres that represent the generators of the second homology of the 4-manifold. This naturally extends r-shake slice, a generalization of slice that has previously only been studied for knots, to links of more than one component. We also define a relative notion of shaker-concordance for links and versions with stricter conditions on the embedded spheres that we …

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Quantifying Spatiotemporal Variability In Zooplankton Dynamics In The Gulf Of Mexico With A Physical-Biogeochemical Model, Taylor A. Shropshire, Steven L. Morey, Eric P. Chassignet, Alexandra Bozec, Victoria J. Coles, Michael R. Landry, Rasmus Swalethorp, Glenn Zapfe, Michael R. Stukel Jul 2020

Quantifying Spatiotemporal Variability In Zooplankton Dynamics In The Gulf Of Mexico With A Physical-Biogeochemical Model, Taylor A. Shropshire, Steven L. Morey, Eric P. Chassignet, Alexandra Bozec, Victoria J. Coles, Michael R. Landry, Rasmus Swalethorp, Glenn Zapfe, Michael R. Stukel

Faculty Publications

© 2020. This work is distributed under the Creative Commons Attribution 4.0 License. Zooplankton play an important role in global biogeochemistry, and their secondary production supports valuable fisheries of the world's oceans. Currently, zooplankton standing stocks cannot be estimated using remote sensing techniques. Hence, coupled physical–biogeochemical models (PBMs) provide an important tool for studying zooplankton on regional and global scales. However, evaluating the accuracy of zooplankton biomass estimates from PBMs has been a major challenge due to sparse observations. In this study, we configure a PBM for the Gulf of Mexico (GoM) from 1993 to 2012 and validate the model …

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Greenwashing No More: The Case For Stronger Regulation Of Environmental Marketing, Robin M. Rotman, Chloe J. Gossett, Hope D. Goldman Jul 2020

Greenwashing No More: The Case For Stronger Regulation Of Environmental Marketing, Robin M. Rotman, Chloe J. Gossett, Hope D. Goldman

Faculty Publications

Fraudulent and deceptive environmental claims in marketing (sometimes called “greenwashing”) are a persistent problem in the United States, despite nearly thirty years of efforts by the Federal Trade Commission (FTC) to prevent it. This Essay focuses on a recent trend in greenwashing - fraudulent “organic” claims for nonagricultural products, such as home goods and personal care products. We offer three recommendations. First, we suggest ways that the FTC can strengthen its oversight of “organic” claims for nonagricultural products and improve coordination with the USDA. Second, we argue for inclusion of guidelines for “organic” claims in the next revision of the …

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Tracking Joint Angles During Whole-Arm Movements Using Electromagnetic Sensors, Ryan Clark, Taylor Dickinson, Johnfredy Loaiza, Daniel W. Geiger, Steven Knight Charles Jul 2020

Tracking Joint Angles During Whole-Arm Movements Using Electromagnetic Sensors, Ryan Clark, Taylor Dickinson, Johnfredy Loaiza, Daniel W. Geiger, Steven Knight Charles

Faculty Publications

Electromagnetic (EM) motion tracking systems are suitable for many research and clinical applications, including in-vivo measurements of whole-arm movements. Unfortunately, the methodology for in vivo measurements of whole-arm movements using EM sensors is not well described in the literature, making it difficult to perform new measurements and all but impossible to make meaningful comparisons between studies. The recommendations of the International Society of Biomechanics (ISB) have provided a great service, but by necessity they do not provide clear guidance or standardization on all required steps. The goal of this paper was to provide a comprehensive methodology for using EM sensors …

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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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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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Can Children Catch Up From The Consequences Of Undernourishment? Evidence From Child Linear Growth, Developmental Epigenetics, And Brain And Neurocognitive Development, Jef L. Leroy, Edward A. Frongillo Jr., Pragya Dewan, Maureen M. Black, Robert A. Waterland Jul 2020

Can Children Catch Up From The Consequences Of Undernourishment? Evidence From Child Linear Growth, Developmental Epigenetics, And Brain And Neurocognitive Development, Jef L. Leroy, Edward A. Frongillo Jr., Pragya Dewan, Maureen M. Black, Robert A. Waterland

Faculty Publications

Recovery from nutritionally induced height deficits continues to garner attention. The current literature on catch-up growth, however, has 2 important limitations: wide-ranging definitions of catch-up growth are used, and it remains unclear whether children can recover from the broader consequences of undernutrition. We addressed these shortcomings by reviewing the literature on the criteria for catch-up in linear growth and on the potential to recover from undernutrition early in life in 3 domains: linear growth, developmental epigenetics, and child brain and neurocognitive development. Four criteria must be met to demonstrate catch-up growth in height: after a period in which a growth-inhibiting …

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Applications Of Portable Libs For Actinide Analysis, Ashwin P. Rao, John D. Auxier Ii, Dung Vu, Michael B. Shattan Jul 2020

Applications Of Portable Libs For Actinide Analysis, Ashwin P. Rao, John D. Auxier Ii, Dung Vu, Michael B. Shattan

Faculty Publications

A portable LIBS device was used for rapid elemental impurity analysis of plutonium alloys. This device demonstrates the potential for fast, accurate in-situ chemical analysis and could significantly reduce the fabrication time of plutonium alloys.

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Implications Of Four-Dimensional Weather Cubes For Improved Cloud-Free Line-Of-Sight Assessments Of Free-Space Optical Communications Link Performance, Steven T. Fiorino, Santasri Bose-Pillai, Jaclyn Schmidt, Brannon Elmore, Kevin J. Keefer Jul 2020

Implications Of Four-Dimensional Weather Cubes For Improved Cloud-Free Line-Of-Sight Assessments Of Free-Space Optical Communications Link Performance, Steven T. Fiorino, Santasri Bose-Pillai, Jaclyn Schmidt, Brannon Elmore, Kevin J. Keefer

Faculty Publications

We advance the benefits of previously reported four-dimensional (4-D) weather cubes toward the creation of high-fidelity cloud-free line-of-sight (CFLOS) beam propagation for realistic assessment of autotracked/dynamically routed free-space optical (FSO) communication datalink concepts. The weather cubes accrue parameterization of optical effects and custom atmospheric resolution through implementation of numerical weather prediction data in the Laser Environmental Effects Definition and Reference atmospheric characterization and radiative transfer code. 4-D weather cube analyses have recently been expanded to accurately assess system performance (probabilistic climatologies and performance forecasts) at any wavelength/frequency or spectral band in the absence of field tests and employment data. The …

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The Arabidopsis Transcription Factor Aintegumenta Orchestrates Patterning Genes And Auxin Signaling In The Establishment Of Floral Growth And Form, Beth A. Krizek, Ivory C. Blakley, Yen Yi Ho, Nowlan Freese, Ann E. Loraine Jul 2020

The Arabidopsis Transcription Factor Aintegumenta Orchestrates Patterning Genes And Auxin Signaling In The Establishment Of Floral Growth And Form, Beth A. Krizek, Ivory C. Blakley, Yen Yi Ho, Nowlan Freese, Ann E. Loraine

Faculty Publications

Understanding how flowers form is an important problem in plant biology, as human food supply depends on flower and seed production. Flower development also provides an excellent model for understanding how cell division, expansion and differentiation are coordinated during organogenesis. In the model plant Arabidopsis thaliana, floral organogenesis requires AINTEGUMENTA (ANT) and AINTEGUMENTA-LIKE 6 (AIL6)/PLETHORA 3 (PLT3), two members of the Arabidopsis AINTEGUMENTA-LIKE/PLETHORA (AIL/PLT) transcription factor family. Together, ANT and AIL6/PLT3 regulate aspects of floral organogenesis, including floral organ initiation, growth, identity specification and patterning. Previously, we used RNA-Seq to identify thousands of genes with disrupted expression in ant ail6 …

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Meeting Report Of The Third Annual Tri-Service Microbiome Consortium Symposium, J Philip Karl, Robyn A. Barbato, Laurel A. Doherty, Aarti Gautam, Sarah M. Glaven, Robert J. Kokoska, Dagmar Leary, Rebecca Mickol, Matthew A. Perisin, Andrew J. Hoisington, Edward J. Van Opstal, Vanessa Varaljay, Nancy Kelley-Loughnane, Camilla A. Mauzy, Michael S. Goodson, Jason W. Soares Jul 2020

Meeting Report Of The Third Annual Tri-Service Microbiome Consortium Symposium, J Philip Karl, Robyn A. Barbato, Laurel A. Doherty, Aarti Gautam, Sarah M. Glaven, Robert J. Kokoska, Dagmar Leary, Rebecca Mickol, Matthew A. Perisin, Andrew J. Hoisington, Edward J. Van Opstal, Vanessa Varaljay, Nancy Kelley-Loughnane, Camilla A. Mauzy, Michael S. Goodson, Jason W. Soares

Faculty Publications

The Tri-Service Microbiome Consortium (TSMC) was founded to enhance collaboration, coordination, and communication of microbiome research among U.S. Department of Defense (DoD) organizations and to facilitate resource, material and information sharing among consortium members. The 2019 annual symposium was held 22–24 October 2019 at Wright-Patterson Air Force Base in Dayton, OH. Presentations and discussions centered on microbiome-related topics within five broad thematic areas: 1) human microbiomes; 2) transitioning products into Warfighter solutions; 3) environmental microbiomes; 4) engineering microbiomes; and 5) microbiome simulation and characterization. Collectively, the symposium provided an update on the scope of current DoD microbiome research efforts, highlighted …

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Groundwater Level Mapping Tool: An Open Source Web Application For Assessing Groundwater Sustainability, Steven W. Evans, Norman L. Jones, Gustavious P. Williams, Daniel P. Ames, E. James Nelson Jul 2020

Groundwater Level Mapping Tool: An Open Source Web Application For Assessing Groundwater Sustainability, Steven W. Evans, Norman L. Jones, Gustavious P. Williams, Daniel P. Ames, E. James Nelson

Faculty Publications

Decision makers need an accurate understanding of aquifer storage trends to effectively manage groundwater resources. Groundwater is difficult to monitor and quantify since the data collected from monitoring wells are often available only at irregular and infrequent intervals. We present an open-source web application (app) to visualize groundwater data over time and automatically calculate changes in aquifer storage volume to help managers assess aquifer sustainability. This app uses a novel multi-linear regression (MLR) algorithm to impute missing data for infrequently sampled wells, using correlated data from other wells in the same aquifer. The app uses this MLR-imputed data to spatially …

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Measurements Of Optical Turbulence Over 149-Km Path, Jack E. Mccrae, Santasri Bose-Pillai, Steven T. Fiorino, Aaron J. Archibald, Joel Meoak, Brannon Elmore, Thomas Kesler, Christopher A. Rice Jul 2020

Measurements Of Optical Turbulence Over 149-Km Path, Jack E. Mccrae, Santasri Bose-Pillai, Steven T. Fiorino, Aaron J. Archibald, Joel Meoak, Brannon Elmore, Thomas Kesler, Christopher A. Rice

Faculty Publications

An experiment was conducted to study turbulence along a 149-km path between the Mauna Loa and Haleakala mountain tops using digital cameras and light-emitting diode (LED) beacons. Much of the path is over the ocean, and a large portion of the path is 3 km above sea level. On the Mauna Loa side, six LED beacons were placed in a roughly linear array with pair spacings from 7 to 62 m. From the Haleakala side, a pair of cameras separated by 83.8 cm observed these beacons. Turbulence along the path induces tilts on the wavefronts, which results in displacements of …

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Turbulence Profiling Using Pupil Plane Wavefront Data Derived Fried Parameter Values For A Dynamically Ranged Rayleigh Beacon, Steven M. Zuraski, Elizabeth Beecher, Jack E. Mccrae, Steven T. Fiorino Jul 2020

Turbulence Profiling Using Pupil Plane Wavefront Data Derived Fried Parameter Values For A Dynamically Ranged Rayleigh Beacon, Steven M. Zuraski, Elizabeth Beecher, Jack E. Mccrae, Steven T. Fiorino

Faculty Publications

Long-range optical imaging applications are typically hindered by atmospheric turbulence. The effect of turbulence on an imaging system can manifest itself as an image blur effect usually quantified by the phase distortions present in the system. The blurring effect can be understood on the basis of the measured strength of atmospheric optical turbulence along the propagation path and its impacts on phase perturbation statistics within the imaging system. One method for obtaining these measurements is by the use of a dynamically ranged Rayleigh beacon system that exploits strategically varied beacon ranges along the propagation path, effectively obtaining estimates of the …

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Wave-Optics Investigation Of Turbulence Thermal Blooming Interaction: I. Using Steady-State Simulations, Mark F. Spencer Jul 2020

Wave-Optics Investigation Of Turbulence Thermal Blooming Interaction: I. Using Steady-State Simulations, Mark F. Spencer

Faculty Publications

Part I of this two-part paper uses wave-optics simulations to look at the Monte Carlo averages associated with turbulence and steady-state thermal blooming (SSTB). The goal is to investigate turbulence thermal blooming interaction (TTBI). At wavelengths near 1 μm, TTBI increases the amount of constructive and destructive interference (i.e., scintillation) that results from high-power laser beam propagation through distributed-volume atmospheric aberrations. As a result, we use the spherical-wave Rytov number and the distortion number to gauge the strength of the simulated turbulence and SSTB. These parameters simplify greatly given propagation paths with constant atmospheric conditions. In addition, we use the …

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Wave-Optics Investigation Of Turbulence Thermal Blooming Interaction: Ii. Using Time-Dependent Simulations, Mark F. Spencer Jul 2020

Wave-Optics Investigation Of Turbulence Thermal Blooming Interaction: Ii. Using Time-Dependent Simulations, Mark F. Spencer

Faculty Publications

Part II of this two-part paper uses wave-optics simulations to look at the Monte Carlo averages associated with turbulence and time-dependent thermal blooming (TDTB). The goal is to investigate turbulence thermal blooming interaction (TTBI). At wavelengths near 1 μm, TTBI increases the amount of constructive and destructive interference (i.e., scintillation) that results from high-power laser beam propagation through distributed-volume atmospheric aberrations. As a result, we use the spherical-wave Rytov number, the number of wind-clearing periods, and the distortion number to gauge the strength of the simulated turbulence and TDTB. These parameters simply greatly given propagation paths with constant atmospheric conditions. …

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Cyberspace Odyssey: A Competitive Team-Oriented Serious Game In Computer Networking, Kendra Graham, James Anderson, Conrad Rife, Bryce Heitmeyer, Pranav R. Patel, Scott L. Nykl, Alan C. Lin, Laurence D. Merkle Jul 2020

Cyberspace Odyssey: A Competitive Team-Oriented Serious Game In Computer Networking, Kendra Graham, James Anderson, Conrad Rife, Bryce Heitmeyer, Pranav R. Patel, Scott L. Nykl, Alan C. Lin, Laurence D. Merkle

Faculty Publications

Cyber Space Odyssey (CSO) is a novel serious game supporting computer networking education by engaging students in a race to successfully perform various cybersecurity tasks in order to collect clues and solve a puzzle in virtual near-Earth 3D space. Each team interacts with the game server through a dedicated client presenting a multimodal interface, using a game controller for navigation and various desktop computer networking tools of the trade for cybersecurity tasks on the game's physical network. Specifically, teams connect to wireless access points, use packet monitors to intercept network traffic, decrypt and reverse engineer that traffic, craft well-formed and …

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Heterometallic Multinuclear Nodes Directing Mof Electronic Behavior, Otega A. Ejegbavwo, Anna A. Berseneva, Corey R. Martin, Gabrielle A. Leith, Shubham Pandey, Amy J. Brandt, Kyoung Chul Park, Abhijai Mathur, Sharfa Farzandh, Vladislav V. Klepov, Brittany J. Heiser, Mvs Chandrashekhar, Stavros G. Karakalos, Mark D. Smith, Simon R. Phillpot, Sophya Garashchuk, Donna A. Chen, Natalia B. Shustova Prof. Dr. Jun 2020

Heterometallic Multinuclear Nodes Directing Mof Electronic Behavior, Otega A. Ejegbavwo, Anna A. Berseneva, Corey R. Martin, Gabrielle A. Leith, Shubham Pandey, Amy J. Brandt, Kyoung Chul Park, Abhijai Mathur, Sharfa Farzandh, Vladislav V. Klepov, Brittany J. Heiser, Mvs Chandrashekhar, Stavros G. Karakalos, Mark D. Smith, Simon R. Phillpot, Sophya Garashchuk, Donna A. Chen, Natalia B. Shustova Prof. Dr.

Faculty Publications

Metal node engineering in combination with modularity, topological diversity, and porosity of metal–organic frameworks (MOFs) could advance energy and optoelectronic sectors. In this study, we focus on MOFs with multinuclear heterometallic nodes for establishing metal−property trends, i.e., connecting atomic scale changes with macroscopic material properties by utilization of inductively coupled plasma mass spectrometry, conductivity measurements, X-ray photoelectron and diffuse reflectance spectroscopies, and density functional theory calculations. The results of Bader charge analysis and studies employing the Voronoi–Dirichlet partition of crystal structures are also presented. As an example of frameworks with different nodal arrangements, we have chosen MOFs with mononuclear, …

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Predictions For The Cosmic Microwave Background From An Anisotropic Quantum Bounce, Ivan Agullo, Javier Olmedo, V. Sreenath Jun 2020

Predictions For The Cosmic Microwave Background From An Anisotropic Quantum Bounce, Ivan Agullo, Javier Olmedo, V. Sreenath

Faculty Publications

We introduce an extension of the standard inflationary paradigm on which the big bang singularity is replaced by an anisotropic bounce. Unlike in the big bang model, cosmological perturbations find an adiabatic regime in the past. We show that this scenario accounts for the observed quadrupolar modulation in the temperature anisotropies of the cosmic microwave background, and we make predictions for the polarization angular correlation functions E-E, B-B, and E-B, together with temperature-polarization correlations T-B and T-E, that can be used to test our ideas. We base our calculations on the bounce predicted by loop quantum cosmology, but our techniques …

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