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Articles 1531 - 1560 of 24230

Full-Text Articles in Physical Sciences and Mathematics

Users’ Sentiment Analysis Toward National Digital Library Of India: A Quantitative Approach For Understanding User Perception, Ritu Sharma, Sarita Gulati, Amanpreet Kaur, Rupak Chakravarty Sep 2021

Users’ Sentiment Analysis Toward National Digital Library Of India: A Quantitative Approach For Understanding User Perception, Ritu Sharma, Sarita Gulati, Amanpreet Kaur, Rupak Chakravarty

Library Philosophy and Practice (e-journal)

Sentiment analysis is also known as opinion mining. Sentiment analysis is contextual mining of text which identifies and extracts subjective information in textual data. It is extremely used by business, educational organizations, and social media monitoring to gain the general outlook of the wide public regarding their product and policy. The current study looks for gaining insights into user reviews on the National Digital Library of India (NDLI) mobile app (android and iOS). For this purpose, sentiment analysis will be used. It yields an average of 3.64/5 ratings based on 11,861 reviews. The dataset includes a total of 4560 user …


Based On Atmospheric Physics And Ecological Principle To Assess The Accuracies Of Field Co2 /H2o Measurements From Infrared Gas Analyzers In Closed-Path Eddy-Covariance Systems, Xinhua Zhou, Tian Gao, Yunchao Pang, Hayden Mahan, Xiufen Li, Ning Zheng, Andrew E. Suyker, Tala Awada, Jiaojun Zhu Sep 2021

Based On Atmospheric Physics And Ecological Principle To Assess The Accuracies Of Field Co2 /H2o Measurements From Infrared Gas Analyzers In Closed-Path Eddy-Covariance Systems, Xinhua Zhou, Tian Gao, Yunchao Pang, Hayden Mahan, Xiufen Li, Ning Zheng, Andrew E. Suyker, Tala Awada, Jiaojun Zhu

School of Natural Resources: Faculty Publications

Field CO2 /H2O measurements from infrared gas analyzers in closed-path eddy-covariance systems have wide applications in earth sciences. Knowledge about exactness of these measurements is required to assess measurement applicability. Although the analyzers are specified with uncertainty components (zero drift, gain drift, cross-sensitivities, and precision), exactness for individual measurements is unavailable due to an absence of methodology to comprehend the components as an overall uncertainty. Adopting an advanced definition of accuracy as a range of all measurement uncertainty sources, the specified components are composited into a model formulated for studying analyzers’ CO2 /H2O accuracy …


Lethal Microbial Blooms Delayed Freshwater Ecosystem Recovery Following The End-Permian Extinction, Chris Mays, Stephen Mcloughlin, Tracy D. Frank, Christopher R. Fielding, Sam M. Slater, Vivi Vajda Sep 2021

Lethal Microbial Blooms Delayed Freshwater Ecosystem Recovery Following The End-Permian Extinction, Chris Mays, Stephen Mcloughlin, Tracy D. Frank, Christopher R. Fielding, Sam M. Slater, Vivi Vajda

Department of Earth and Atmospheric Sciences: Faculty Publications

Harmful algal and bacterial blooms linked to deforestation, soil loss and global warming are increasingly frequent in lakes and rivers. We demonstrate that climate changes and deforestation can drive recurrent microbial blooms, inhibiting the recovery of freshwater ecosystems for hundreds of millennia. From the stratigraphic successions of the Sydney Basin, Australia, our fossil, sedimentary and geochemical data reveal bloom events following forest ecosystem collapse during the most severe mass extinction in Earth’s history, the end- Permian event (EPE; c. 252.2 Ma). Microbial communities proliferated in lowland fresh and brackish waterbodies, with algal concentrations typical of modern blooms. These initiated before …


Cohomological Blow Ups Of Graded Artinian Gorenstein Algebras Along Surjective Maps, Anthony Iarrobino, Pedro Macias Marques, Chris Mcdaniel, Alexandra Seceleanu, Junzo Watanabe Sep 2021

Cohomological Blow Ups Of Graded Artinian Gorenstein Algebras Along Surjective Maps, Anthony Iarrobino, Pedro Macias Marques, Chris Mcdaniel, Alexandra Seceleanu, Junzo Watanabe

Department of Mathematics: Faculty Publications

We introduce the cohomological blow up of a graded Artinian Gorenstein (AG) algebra along a surjective map, which we term BUG (Blow Up Gorenstein) for short. This is intended to translate to an algebraic context the cohomology ring of a blow up of a projective manifold along a projective submanifold. We show, among other things, that a BUG is a connected sum, that it is the general fiber in a flat family of algebras, and that it preserves the strong Lefschetz property. We also show that standard graded compressed algebras are rarely BUGs, and we classify those BUGs that are …


A Proposed Framework For The Development And Qualitative Evaluation Of West Nile Virus Models And Their Application To Local Public Health Decision-Making, Alexander C. Keyel, Morgan E. Gorris, Ilia Rochlin, Johnny A. Uelmen, Luis F. Chaves, Gabriel L. Hamer, Imelda K. Moise, Marta Shocket, A Marm Kilpatrick, Nicholas B. Defelice, Justin K. Davis, Eliza Little, Patrick Irwin, Andrew J. Tyre, Kelly Helm Smith, Chris L. Fredregill, Oliver Elison Timm, Karen M. Holcomb, Michael C. Wimberly, Matthew J. Ward, Christopher M. Barker, Charlotte G. Rhodes, Rebecca L. Smith Sep 2021

A Proposed Framework For The Development And Qualitative Evaluation Of West Nile Virus Models And Their Application To Local Public Health Decision-Making, Alexander C. Keyel, Morgan E. Gorris, Ilia Rochlin, Johnny A. Uelmen, Luis F. Chaves, Gabriel L. Hamer, Imelda K. Moise, Marta Shocket, A Marm Kilpatrick, Nicholas B. Defelice, Justin K. Davis, Eliza Little, Patrick Irwin, Andrew J. Tyre, Kelly Helm Smith, Chris L. Fredregill, Oliver Elison Timm, Karen M. Holcomb, Michael C. Wimberly, Matthew J. Ward, Christopher M. Barker, Charlotte G. Rhodes, Rebecca L. Smith

School of Natural Resources: Faculty Publications

West Nile virus(WNV) is a globally distributed mosquito-borne virus of great public health concern. The number of WNV human cases and mosquito infection patterns vary in space and time. Many statistical models have been developed to understand and predict WNV geographic and temporal dynamics. However, these modeling efforts have been disjointed with little model comparison and inconsistent validation. In this paper, we describe a framework to unify and standardize WNV modeling efforts nationwide. WNV risk, detection, or warning models for this review were solicited from active research groups working in different regions of the United States. A total of 13 …


Prediction Of Biome-Specific Potential Evapotranspiration In Mongolia Under A Scarcity Of Weather Data, Khulan Batsukh, Vitaly A. Zlotnik, Andrew E. Suyker, Paolo Nasta Sep 2021

Prediction Of Biome-Specific Potential Evapotranspiration In Mongolia Under A Scarcity Of Weather Data, Khulan Batsukh, Vitaly A. Zlotnik, Andrew E. Suyker, Paolo Nasta

Department of Earth and Atmospheric Sciences: Faculty Publications

We propose practical guidelines to predict biome-specific potential evapotranspiration (ETp) from the knowledge of grass-reference evapotranspiration (ET0) and a crop coefficient (Kc) in Mongolia. A paucity of land-based weather data hampers use of the Penman–Monteith equation (FAO-56 PM) based on the Food and Agriculture Organization (FAO) guidelines to predict daily ET0. We found that the application of the Hargreaves equation provides ET0 estimates very similar to those from the FAO-56 PM approach. The Kc value is tabulated only for crops in the FAO-56 guidelines but is unavailable …


High-Frequency And Below Bandgap Anisotropic Dielectric Constants In Α-(AlXGa1-X)2O3 (0≤X≤1), Matthew Hilfiker, Ufuk Kilic, Megan Stokey, Riena Jinno, Yongjin Cho, Huili Grace Xing, Debdeep Jena, Rafal Korlacki, Mathias Schubert Sep 2021

High-Frequency And Below Bandgap Anisotropic Dielectric Constants In Α-(AlXGa1-X)2O3 (0≤X≤1), Matthew Hilfiker, Ufuk Kilic, Megan Stokey, Riena Jinno, Yongjin Cho, Huili Grace Xing, Debdeep Jena, Rafal Korlacki, Mathias Schubert

Department of Electrical and Computer Engineering: Faculty Publications

A Mueller matrix spectroscopic ellipsometry approach was used to investigate the anisotropic dielectric constants of corundum α-(AlxGa1-x)2O3 thin films in their below bandgap spectral regions. The sample set was epitaxially grown using plasma-assisted molecular beam epitaxy on m-plane sapphire. The spectroscopic ellipsometry measurements were performed at multiple azimuthal angles to resolve the uniaxial dielectric properties. A Cauchy dispersion model was applied, and high-frequency dielectric constants are determined for polarization perpendicular (ε∞,⟂) and parallel (ε∞,∥) to the thin film c-axis. The optical birefringence is negative throughout the …


Evaluation Of Regional Climate Models (Rcms) Using Precipitation And Temperature-Based Climatic Indices: A Case Study Of Florida, Usa, Yared Bayissa, Assefa Melesse, Mahadev Bhat, Tsegaye Tadesse, Andualem Shiferaw Sep 2021

Evaluation Of Regional Climate Models (Rcms) Using Precipitation And Temperature-Based Climatic Indices: A Case Study Of Florida, Usa, Yared Bayissa, Assefa Melesse, Mahadev Bhat, Tsegaye Tadesse, Andualem Shiferaw

School of Natural Resources: Faculty Publications

The overarching objective of this study was to evaluate the performance of nine precipitation-based and twelve temperature-based climatic indices derived from four regional climate models (CRCM5-UQUAM, CanRCM4, RCA4 and HIRHAM5) driven by three global circulation models (CanESM2, EC-EARTH and MPI-ESM-LR) and their ensemble mean for the reference period of 31 years (1975–2005). The absolute biases, pattern correlation, the reduction of variance (RV) and the Standardized Precipitation Evapotranspiration Index (SPEI at 3-, 6- and 12-month aggregate periods) techniques were used to evaluate the climate model simulations. The result, in general, shows each climate model has a skill in reproducing at least …


Multi-Feature Data Repository Development And Analytics For Image Cosegmentation In High-Throughput Plant Phenotyping, Rubi Quiñones, Francisco Munoz-Arriola, Sruti Das Choudhury, Ashok Samal Sep 2021

Multi-Feature Data Repository Development And Analytics For Image Cosegmentation In High-Throughput Plant Phenotyping, Rubi Quiñones, Francisco Munoz-Arriola, Sruti Das Choudhury, Ashok Samal

School of Computing: Faculty Publications

Cosegmentation is a newly emerging computer vision technique used to segment an object from the background by processing multiple images at the same time. Traditional plant phenotyping analysis uses thresholding segmentation methods which result in high segmentation accuracy. Although there are proposed machine learning and deep learning algorithms for plant segmentation, predictions rely on the specific features being present in the training set. The need for a multi-featured dataset and analytics for cosegmentation becomes critical to better understand and predict plants’ responses to the environment. High-throughput phenotyping produces an abundance of data that can be leveraged to improve segmentation accuracy …


Plague Exposure In Mammalian Wildlife Across The Western United States, Sarah N. Bevins, Jeffrey C. Chandler, Nicole Barrett, Brandon S. Schmit, Gerald W. Wiscomb, Susan A. Shriner Sep 2021

Plague Exposure In Mammalian Wildlife Across The Western United States, Sarah N. Bevins, Jeffrey C. Chandler, Nicole Barrett, Brandon S. Schmit, Gerald W. Wiscomb, Susan A. Shriner

United States Department of Agriculture Wildlife Services: Staff Publications

Plague is caused by a bacterial pathogen (Yersinia pestis) that can infect a wide range of mammal species, but its presence in wildlife is often underappreciated. Using a large-scale data set (n = 44,857) that details the extent of Y. pestis exposure in wildlife, we document exposure in 18 wildlife species, including coyotes (Canis latrans), bobcats (Lynx rufus), and black bears (Ursus americanus). Evidence of plague activity is widespread, with seropositive animals detected in every western state in the contiguous United States. Pathogen monitoring systems in wildlife that are both large scale …


Spontaneous Fluctuations In A Magnetic Fe/Gd Skyrmion Lattice, M. H. Seaberg, B. Holladay, S. A. Montoya, X. Y. Zheng, J. C.T. Lee, A. H. Reid, J. D. Koralek, L. Shen, V. Esposito, G. Coslovich, P. Walter, S. Zohar, V. Thampy, M. F. Lin, P. Hart, K. Nakahara, R. Streubel, S. D. Kevan, P. Fischer, W. Colocho, A. Lutman, F. J. Decker, E. E. Fullerton, M. Dunne, S. Roy, S. K. Sinha, J. J. Turner Sep 2021

Spontaneous Fluctuations In A Magnetic Fe/Gd Skyrmion Lattice, M. H. Seaberg, B. Holladay, S. A. Montoya, X. Y. Zheng, J. C.T. Lee, A. H. Reid, J. D. Koralek, L. Shen, V. Esposito, G. Coslovich, P. Walter, S. Zohar, V. Thampy, M. F. Lin, P. Hart, K. Nakahara, R. Streubel, S. D. Kevan, P. Fischer, W. Colocho, A. Lutman, F. J. Decker, E. E. Fullerton, M. Dunne, S. Roy, S. K. Sinha, J. J. Turner

Robert Streubel Papers

Magnetic skyrmions are topological spin textures that exhibit classical or quantum quasiparticle behavior. A substantial amount of research has occurred in this field, both because of their unique electromagnetic properties and potential application for future nonvolatile memory storage applications, as well as fundamental questions on their topology and unique magnetic phases. Here, we investigate the fluctuation properties of a magnetic Fe/Gd skyrmion lattice, using short-pulsed x rays. We first measure spontaneous fluctuations of the skyrmion lattice phase and find an inherent, collective mode showing an underdamped oscillation with a relaxation of a couple of nanoseconds. Further observations track the response …


Improving Animal Monitoring Using Small Unmanned Aircraft Systems (Suas) And Deep Learning Networks, Meilun Zhou, Jared A. Elmore, Sathishkumar Samiappan, Kristine O. Evans, Morgan Pfeiffer, Bradley F. Blackwell, Raymond B. Iglay Sep 2021

Improving Animal Monitoring Using Small Unmanned Aircraft Systems (Suas) And Deep Learning Networks, Meilun Zhou, Jared A. Elmore, Sathishkumar Samiappan, Kristine O. Evans, Morgan Pfeiffer, Bradley F. Blackwell, Raymond B. Iglay

United States Department of Agriculture Wildlife Services: Staff Publications

In recent years, small unmanned aircraft systems (sUAS) have been used widely to monitor animals because of their customizability, ease of operating, ability to access difficult to navigate places, and potential to minimize disturbance to animals. Automatic identification and classification of animals through images acquired using a sUAS may solve critical problems such as monitoring large areas with high vehicle traffic for animals to prevent collisions, such as animal-aircraft collisions on airports. In this research we demonstrate automated identification of four animal species using deep learning animal classification models trained on sUAS collected images. We used a sUAS mounted with …


Scaup Depredation On Arkansas Baitfish And Sportfish Aquaculture, Stephen A. Clements, Brian S. Dorr, J. Brian Davis, Luke A. Roy, Carole R. Engle, Katie C. Hanson-Dorr, Anita M. Kelly Sep 2021

Scaup Depredation On Arkansas Baitfish And Sportfish Aquaculture, Stephen A. Clements, Brian S. Dorr, J. Brian Davis, Luke A. Roy, Carole R. Engle, Katie C. Hanson-Dorr, Anita M. Kelly

United States Department of Agriculture Wildlife Services: Staff Publications

Lesser scaup (Aythya affinis) and greater scaup (A. marila), hereafter scaup, consume a variety of aquatic invertebrates, plants, and occasionally small fish. Scaup have foraged on commercial aquaculture farms in the southern United States for decades. However, the types, abundance, and rate of fish exploitation by scaup on baitfish and sportfish farms are not well documented. Thus, information is needed to understand how fish and other foods influence scaup use of aquatic resources, and any potential economic effects of depredation of fish. From November–March in winters 2016–2017 and 2017–2018, we conducted 1,458 pond surveys to estimate …


Data-Driven Management—A Dynamic Occupancy Approach To Enhanced Rabies Surveillance Prioritization, Amy J. Davis, Jordana D. Kirby, Richard B. Chipman, Kathleen M. Nelson, Amy T. Gilbert Sep 2021

Data-Driven Management—A Dynamic Occupancy Approach To Enhanced Rabies Surveillance Prioritization, Amy J. Davis, Jordana D. Kirby, Richard B. Chipman, Kathleen M. Nelson, Amy T. Gilbert

United States Department of Agriculture Wildlife Services: Staff Publications

Rabies lyssavirus (RABV) is enzootic in raccoons across the eastern United States. Intensive management of RABV by oral rabies vaccination (ORV) has prevented its spread westward and shown evidence of local elimination in raccoon populations of the northeastern US. The USDA, Wildlife Services, National Rabies Management Program (NRMP) collaborates with other agencies to implement broad-scale ORV and conducts extensive monitoring to measure the effectiveness of the management. Enhanced Rabies Surveillance (ERS) was initiated during 2005 and updated in 2016 to direct surveillance efforts toward higher-value specimens by assigning points to different methods of encountering specimens for collection (strange-acting, roadkill, surveillance-trapped, …


Spatial Variation In Direct And Indirect Contact Rates At The Wildlife-Livestock Interface For Informing Disease Management, Anni Yang, Raoul K. Boughton, Ryan S. Miller, Bethany Wight, Wesley M. Anderson, James C. Beasley, Kurt C. Vercauteren, Kim M. Pepin, George Wittemyer Sep 2021

Spatial Variation In Direct And Indirect Contact Rates At The Wildlife-Livestock Interface For Informing Disease Management, Anni Yang, Raoul K. Boughton, Ryan S. Miller, Bethany Wight, Wesley M. Anderson, James C. Beasley, Kurt C. Vercauteren, Kim M. Pepin, George Wittemyer

United States Department of Agriculture Wildlife Services: Staff Publications

Little is known about disease transmission relevant contact rates at the wildlife-livestock interface and the factors shaping them. Indirect contact via shared resources is thought to be important but remains unquantified in most systems, making it challenging to evaluate the impact of livestock management practices on contact networks. Free-ranging wild pigs (Sus scrofa) in North America are an invasive, socially-structured species with an expanding distribution that pose a threat to livestock health given their potential to transmit numerous livestock diseases, such as pseudorabies, brucellosis, trichinellosis, and echinococcosis, among many others. Our objective in this study was to quantify …


Posterior Propriety Of An Objective Prior For Generalized Hierarchical Normal Linear Models, Cong Lin, Dongchu Sun, Chengyuan Song Aug 2021

Posterior Propriety Of An Objective Prior For Generalized Hierarchical Normal Linear Models, Cong Lin, Dongchu Sun, Chengyuan Song

Department of Statistics: Faculty Publications

Bayesian Hierarchical models has been widely used in modern statistical application. To deal with the data having complex structures, we propose a generalized hierarchical normal linear (GHNL) model which accommodates arbitrarily many levels, usual design matrices and ‘vanilla’ covariance matrices. Objective hyperpriors can be employed for the GHNL model to express ignorance or match frequentist properties, yet the common objective Bayesian approaches are infeasible or fraught with danger in hierarchical modelling. To tackle this issue, [Berger, J., Sun, D., & Song, C. (2020b). An objective prior for hyperparameters in normal hierarchical models. Journal of Multivariate Analysis, 178, 104606. https://doi.org/10.1016/j.jmva.2020.104606] …


Spin-Orbit Dependence Of Anisotropic Current-Induced Spin Polarization, L. L. Tao, Evgeny Y. Tsymbal Aug 2021

Spin-Orbit Dependence Of Anisotropic Current-Induced Spin Polarization, L. L. Tao, Evgeny Y. Tsymbal

Department of Physics and Astronomy: Faculty Publications

Studies of the current-induced spin polarization (CISP) have been recently reinvigorated due to the discoveries of CISP in some burgeoning materials such as oxide interfaces, van der Waals, and topological quantum materials. Here, we investigate the CISP in two-dimensional systems for different types of spin-orbit coupling (SOC) using the Boltzmann transport theory. We find an anisotropic response of CISP to the current direction which strongly depends on the type of SOC. We demonstrate that the CISP is nonlinear with respect to the SOC magnitude, depends on the Fermi energy, and exhibits two different transport regimes for low or high carrier …


Monitoring Agroecosystem Productivity And Phenology At A National Scale: A Metric Assessment Framework, Dawn M. Browning, Eric S. Russell, Guillermo E. Ponce-Campos, Nicole Kaplan, Andrew D. Richardson, Bijan Seyednasrollah, Sheri Spiegal, Nicanor Saliendra, Joseph G. Alfieri, John Baker, Carl Bernacchi, Brandon T. Bestelmeyer, David Bosch, Elizabeth H. Boughton, Raoul K. Boughton, Pat Clark, Gerald Flerchinger, Nuria Gomez-Casanovas, Sarah Goslee, Nick M. Haddad, David Hoover, Abdullah Jaradat, Marguerite Mauritz, Gregory W. Mccarty, Gretchen R. Miller, John Sadler, Amartya Saha, Russell L. Scott, Andrew Suyker, Craig Tweedie, Jeffrey D. Wood, Xukai Zhang, Shawn D. Taylor Aug 2021

Monitoring Agroecosystem Productivity And Phenology At A National Scale: A Metric Assessment Framework, Dawn M. Browning, Eric S. Russell, Guillermo E. Ponce-Campos, Nicole Kaplan, Andrew D. Richardson, Bijan Seyednasrollah, Sheri Spiegal, Nicanor Saliendra, Joseph G. Alfieri, John Baker, Carl Bernacchi, Brandon T. Bestelmeyer, David Bosch, Elizabeth H. Boughton, Raoul K. Boughton, Pat Clark, Gerald Flerchinger, Nuria Gomez-Casanovas, Sarah Goslee, Nick M. Haddad, David Hoover, Abdullah Jaradat, Marguerite Mauritz, Gregory W. Mccarty, Gretchen R. Miller, John Sadler, Amartya Saha, Russell L. Scott, Andrew Suyker, Craig Tweedie, Jeffrey D. Wood, Xukai Zhang, Shawn D. Taylor

School of Natural Resources: Faculty Publications

Effective measurement of seasonal variations in the timing and amount of production is critical to managing spatially heterogeneous agroecosystems in a changing climate. Although numerous technologies for such measurements are available, their relationships to one another at a continental extent are unknown. Using data collected from across the Long-Term Agroecosystem Research (LTAR) network and other networks, we investigated correlations among key metrics representing primary production, phenology, and carbon fluxes in croplands, grazing lands, and crop-grazing integrated systems across the continental U.S. Metrics we examined included gross primary productivity (GPP) estimated from eddy covariance (EC) towers and modelled from the Landsat …


New Insights Into The Drainage Of Inundated Ice-Wedge Polygons Using Fundamental Hydrologic Principles, Dylan R. Harp, Vitaly A. Zlotnik, Charles J. Abolt, Bob Busey3, Sofia T. Avendaño, Brent D. Newman, Adam L. Atchley, Elchin Jafarov, Cathy J. Wilson, Katrina E. Bennett Aug 2021

New Insights Into The Drainage Of Inundated Ice-Wedge Polygons Using Fundamental Hydrologic Principles, Dylan R. Harp, Vitaly A. Zlotnik, Charles J. Abolt, Bob Busey3, Sofia T. Avendaño, Brent D. Newman, Adam L. Atchley, Elchin Jafarov, Cathy J. Wilson, Katrina E. Bennett

Department of Earth and Atmospheric Sciences: Faculty Publications

The pathways and timing of drainage from the inundated centers of ice-wedge polygons in a warming climate have important implications for carbon flushing, advective heat transport, and transitions from methane to carbon dioxide dominated emissions. Here, we expand on previous research using a recently developed analytical model of drainage from a low-centered polygon. Specifically, we perform (1) a calibration to field data identifying necessary model refinements and (2) a rigorous model sensitivity analysis that expands on previously published indications of polygon drainage characteristics. This research provides intuition on inundated polygon drainage by presenting the first in-depth analysis of drainage within …


Bernstein-Sato Polynomials In Commutative Algebra, Josep Àlvarez Montaner, Jack Jeffries, Luis Núñez-Betancourt Aug 2021

Bernstein-Sato Polynomials In Commutative Algebra, Josep Àlvarez Montaner, Jack Jeffries, Luis Núñez-Betancourt

Department of Mathematics: Faculty Publications

This is an expository survey on the theory of Bernstein-Sato polynomials with special emphasis in its recent developments and its importance in commutative algebra.


Deepsec: A Deep Learning Framework For Secreted Protein Discovery In Human Body Fluids, Dan Shao, Lan Huang, Yan Wang, Kai He, Xueteng Cui, Yao Wang, Qin Ma, Juan Cui Aug 2021

Deepsec: A Deep Learning Framework For Secreted Protein Discovery In Human Body Fluids, Dan Shao, Lan Huang, Yan Wang, Kai He, Xueteng Cui, Yao Wang, Qin Ma, Juan Cui

School of Computing: Faculty Publications

Motivation: Human proteins that are secreted into different body fluids from various cells and tissues can be promising disease indicators. Modern proteomics research empowered by both qualitative and quantitative profiling techniques has made great progress in protein discovery in various human fluids. However, due to the large number of proteins and diverse modifications present in the fluids, as well as the existing technical limits of major proteomics platforms (e.g. mass spectrometry), large discrepancies are often generated from different experimental studies. As a result, a comprehensive proteomics landscape across major human fluids are not well determined.

Results: To bridge …


Lower Bounds On Betti Numbers, Adam Boocher, Eloisa Grifo Aug 2021

Lower Bounds On Betti Numbers, Adam Boocher, Eloisa Grifo

Department of Mathematics: Faculty Publications

We survey recent results on bounds for Betti numbers of modules over polynomial rings, with an emphasis on lower bounds. Along the way, we give a gentle introduction to free resolutions and Betti numbers, and discuss some of the reasons why one would study these.


Groundwater Quality And Age Of Secondary Bedrock Aquifers In The Glaciated Portion Of Eastern Nebraska, 2016–18, Christopher M. Hobza, Amanda T. Flynn Aug 2021

Groundwater Quality And Age Of Secondary Bedrock Aquifers In The Glaciated Portion Of Eastern Nebraska, 2016–18, Christopher M. Hobza, Amanda T. Flynn

United States Geological Survey: Water Reports and Publications

The Eastern Nebraska Water Resources Assessment (ENWRA) project was initiated in 2006 to assist water managers by developing a hydrogeologic framework and water budget for the glaciated portion of eastern Nebraska. Within the ENWRA area, the primary groundwater sources for municipal, domestic, and irrigation water needs are provided by withdrawals from alluvial, buried paleovalley, and the High Plains aquifer (where present). Generally, other bedrock aquifers are considered a secondary water source. However, in some areas, such as parts of Sarpy and Nemaha Counties, these secondary bedrock aquifers are the only source of water within glaciated upland areas. To improve the …


Invader Removal Triggers Competitive Release In A Threatened Avian Predator, J. David Wiens, Katie M. Dugger, J. Mark Higley, Damon B. Lesmeister, Alan B. Franklin, Keith A. Hamm, Gary C. White, Krista E. Dilione, David C. Simon, Robin R. Bown, Peter C. Carlson, Charles B. Yackulic, James D. Nichols, James E. Hines, Raymond J. Davis, David W. Lamphear, Christopher Mccafferty, Trent L. Mcdonald, Stan G. Sovern Aug 2021

Invader Removal Triggers Competitive Release In A Threatened Avian Predator, J. David Wiens, Katie M. Dugger, J. Mark Higley, Damon B. Lesmeister, Alan B. Franklin, Keith A. Hamm, Gary C. White, Krista E. Dilione, David C. Simon, Robin R. Bown, Peter C. Carlson, Charles B. Yackulic, James D. Nichols, James E. Hines, Raymond J. Davis, David W. Lamphear, Christopher Mccafferty, Trent L. Mcdonald, Stan G. Sovern

United States Department of Agriculture Wildlife Services: Staff Publications

Changes in the distribution and abundance of invasive species can have far-reaching ecological consequences. Programs to control invaders are common but gauging the effectiveness of such programs using carefully controlled, large-scale field experiments is rare, especially at higher trophic levels. Experimental manipulations coupled with long-term demographic monitoring can reveal the mechanistic underpinnings of interspecific competition among apex predators and suggest mitigation options for invasive species. We used a large-scale before-after control-impact removal experiment to investigate the effects of an invasive competitor, the barred owl (Strix varia), on the population dynamics of an iconic old-forest native species, the northern spotted owl …


High Sensitivity Multi-Axes Rotation Sensing Using Large Momentum Transfer Point Source Atom Interferometry, Jinyang Li, Gregório R. M. Da Silva, Wayne Cheng-Wei Huang, Mohamed Fouda, Jason Bonacum, Timothy L. Kovachy, Selim M. Shahriar Aug 2021

High Sensitivity Multi-Axes Rotation Sensing Using Large Momentum Transfer Point Source Atom Interferometry, Jinyang Li, Gregório R. M. Da Silva, Wayne Cheng-Wei Huang, Mohamed Fouda, Jason Bonacum, Timothy L. Kovachy, Selim M. Shahriar

Department of Physics and Astronomy: Faculty Publications

A point source interferometer (PSI) is a device where atoms are split and recombined by applying a temporal sequence of Raman pulses during the expansion of a cloud of cold atoms behaving approximately as a point source. The PSI can work as a sensitive multi-axes gyroscope that can automatically filter out the signal from accelerations. The phase shift arising from the rotations is proportional to the momentum transferred to each atom from the Raman pulses. Therefore, by increasing the momentum transfer, it should be possible to enhance the sensitivity of the PSI. Here, we investigate the degree of enhancement in …


Resonant Band Engineering Of Ferroelectric Tunnel Junctions, Jing Su, Xingwen Zheng, Zheng Wen, Tao Li, Shijie Xie, Karin M. Rabe, Xiaohui Liu, Evgeny Y. Tsymbal Aug 2021

Resonant Band Engineering Of Ferroelectric Tunnel Junctions, Jing Su, Xingwen Zheng, Zheng Wen, Tao Li, Shijie Xie, Karin M. Rabe, Xiaohui Liu, Evgeny Y. Tsymbal

Department of Physics and Astronomy: Faculty Publications

We propose energy band engineering to enhance tunneling electroresistance (TER) in ferroelectric tunnel junctions (FTJs). We predict that an ultrathin dielectric layer with a smaller band gap, embedded into a ferroelectric barrier layer, acts as a switch controlling high- and low-conductance states of an FTJ depending on polarization orientation. Using first-principles modeling based on density functional theory, we investigate this phenomenon for a prototypical SrRuO3/BaTiO3/SrRuO3 FTJ with a BaSnO3 monolayer embedded in the BaTiO3 barrier. We show that in such a composite-barrier FTJ, ferroelectric polarization of BaTiO3 shifts the conduction-band minimum of …


Power-Over-Tether Unmanned Aerial System Leveraged For Trajectory Influenced Atmospheric Sensing, Daniel Rico Aug 2021

Power-Over-Tether Unmanned Aerial System Leveraged For Trajectory Influenced Atmospheric Sensing, Daniel Rico

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

The use of unmanned aerial systems (UASs) in agriculture has risen in the past decade and is helping to modernize agriculture. UASs collect and elucidate data previously difficult to obtain and are used to help increase agricultural efficiency and production. Typical commercial off-the-shelf (COTS) UASs are limited by small payloads and short flight times. Such limits inhibit their ability to provide abundant data at multiple spatiotemporal scales. In this thesis, we describe the design and construction of the tethered aircraft unmanned system (TAUS), which is a novel power-over-tether UAS configured for long-term, high throughput atmospheric monitoring with an array of …


Social And Ecological Correlates Of Avian Infection By Haemosporidian Blood Parasites, Ian R. Hoppe Aug 2021

Social And Ecological Correlates Of Avian Infection By Haemosporidian Blood Parasites, Ian R. Hoppe

School of Natural Resources: Dissertations, Theses, and Student Research

Haemosporidian parasites are a significant source of morbidity and mortality for birds. There is growing recognition of the negative consequences of haemosporidian infections for wild birds at individual and population levels. Avian haemosporidians are geographically widespread, have been detected from a phylogenetically diverse array of hosts, and have been the focus of extensive research due to their impacts on birds and their similarity to vector-borne diseases of humans. However, factors influencing haemosporidian transmission, especially transmission between species, are poorly understood. To better understand these influences, we compared prevalence and diversity of haemosporidian blood parasite infections among species in a behaviorally …


Lower Bounds On Betti Numbers, Adam Boocher, Eloisa Grifo Aug 2021

Lower Bounds On Betti Numbers, Adam Boocher, Eloisa Grifo

Department of Mathematics: Faculty Publications

We survey recent results on bounds for Betti numbers of modules over polynomial rings, with an emphasis on lower bounds. Along the way, we give a gentle introduction to free resolutions and Betti numbers, and discuss some of the reasons why one would study these.


A Combinatorial Formula For Kazhdan-Lusztig Polynomials Of Sparse Paving Matroids, George Nasr Aug 2021

A Combinatorial Formula For Kazhdan-Lusztig Polynomials Of Sparse Paving Matroids, George Nasr

Department of Mathematics: Dissertations, Theses, and Student Research

We present a combinatorial formula using skew Young tableaux for the coefficients of Kazhdan-Lusztig polynomials for sparse paving matroids. These matroids are known to be logarithmically almost all matroids, but are conjectured to be almost all matroids. We also show the positivity of these coefficients using our formula. In special cases, such as for uniform matroids, our formula has a nice combinatorial interpretation.

Advisers: Kyungyong Lee and Jamie Radclie