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University of Texas Rio Grande Valley

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Articles 811 - 840 of 2419

Full-Text Articles in Physical Sciences and Mathematics

Coordinating Stem Core Courses For Student Success, Cristina Villalobos, Hyung Won Kim, Timothy J. Huber, Roger Knobel, Shaghayegh Setayesh, Lekshmi Sasidharan, Anahit Galstyan, Andras Balogh May 2021

Coordinating Stem Core Courses For Student Success, Cristina Villalobos, Hyung Won Kim, Timothy J. Huber, Roger Knobel, Shaghayegh Setayesh, Lekshmi Sasidharan, Anahit Galstyan, Andras Balogh

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Research indicates multi-section coordination improves the academic performance of students in STEM education. This paper describes the process of coordination in Precalculus, Calculus 1, and Calculus 2 courses undertaken by a large department that grew from the merger of two institutions through a pilot program, and a project grant. Components introduced in the project courses are documented, including collaborative problem-solving sessions, student learning assistants, Q&A sessions, and additional technology resources. Preliminary data is provided on the impacts of the initiative on student success. The study findings provide a template for coordination, faculty buy-in, and increased student engagement at similar institutions …

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Visualization Of Exact Invariant Solutions Associated With Atmospheric Waves In A Thin Circular Layer, Ranis N. Ibragimov, Lauren D. Mongrain, Benjamin Stimmel, Olga Trozkaya, Guang Lin, Sheng Zhang, Vesselin Vatchev, Daniel Stankiewicz May 2021

Visualization Of Exact Invariant Solutions Associated With Atmospheric Waves In A Thin Circular Layer, Ranis N. Ibragimov, Lauren D. Mongrain, Benjamin Stimmel, Olga Trozkaya, Guang Lin, Sheng Zhang, Vesselin Vatchev, Daniel Stankiewicz

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

The purpose of the research was to investigate the exact solutions of nonlinear shallow water equations associated with planetary equatorial waves corresponding to the Cauchy-Poisson free boundary problem describing the nonstationary motion of an incompressible perfect fluid propagating around a solid circle. We consider water waves for which the ratio of the depth of fluid above the circular bottom to the radius of the circle is small (shallow water).

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Ramanujan Type Congruences For Quotients Of Level 7 Klein Forms, Timothy Huber, Dongxi Ye May 2021

Ramanujan Type Congruences For Quotients Of Level 7 Klein Forms, Timothy Huber, Dongxi Ye

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Klein forms are used to construct generators for the graded algebra of modular forms of level 7. Dissection formulas for the series imply Ramanujan type congruences modulo powers of 7 for a family of generating functions that subsume the counting function for 7-core partitions. The broad class of arithmetic functions considered here enumerate colored partitions by weights determined by parts modulo 7. The method is a prototype for similar analysis of modular forms of level 7 and at other prime levels. As an example of the utility of the dissection method, the paper concludes with a derivation of novel congruences …

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Chemical Shift Assignments Of The N-Terminal Domain Of Psd95 (Psd95-Nt), Yonghong Zhang, Johannes W. Hell, James B. Ames Apr 2021

Chemical Shift Assignments Of The N-Terminal Domain Of Psd95 (Psd95-Nt), Yonghong Zhang, Johannes W. Hell, James B. Ames

Chemistry Faculty Publications and Presentations

Postsynaptic density protein-95 (PSD95) contributes to the postsynaptic architecture of neuronal synapses and plays an important role in controlling synaptic plasticity. The N-terminal domain of PSD95 (residues 1–71, called PSD95-NT) interacts with target proteins (calmodulin, α-actinin-1 and CDKL5), which regulate the Ca2+-dependent degradation of glutamate receptors. We report complete backbone NMR chemical shift assignments of PSD95-NT (BMRB No. 50752).

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Spectral Singularities With Directional Sensitivity, Hamidreza Ramezani Apr 2021

Spectral Singularities With Directional Sensitivity, Hamidreza Ramezani

Physics and Astronomy Faculty Publications and Presentations

We propose a class of spectral singularities that are sensitive to the direction of excitation and arise in nonlinear systems with broken parity symmetry. These spectral singularities are sensitive to the direction of the incident beam and result in diverging transmission and reflection for the left (right) incident, while the transmission and reflection of the right (left) side of the system remain finite. For the pedagogical reason, first we review the scattering formalism in nonlinear systems using an abstract δ-function model. Then, using a parity symmetry broken nonlinear system consisting of two δ functions, one linear and the other nonlinear, …

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Reconstructing Primary Production In A Changing Estuary: A Mass Balance Modeling Approach, Jongsun Kim, Mark J. Brush, Bongkeun Song, Iris C. Anderson Apr 2021

Reconstructing Primary Production In A Changing Estuary: A Mass Balance Modeling Approach, Jongsun Kim, Mark J. Brush, Bongkeun Song, Iris C. Anderson

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Estuarine primary production (PP) is a critical rate process for understanding ecosystem function and response to environmental change. PP is fundamentally linked to estuarine eutrophication, and as such should respond to ongoing efforts to reduce nutrient inputs to estuaries globally. However, concurrent changes including warming, altered hydrology, reduced input of sediments, and emergence of harmful algal blooms (HABs) could interact with nutrient management to produce unexpected changes in PP. Despite its fundamental importance, estuarine PP is rarely measured. We reconstructed PP in the York River Estuary with a novel mass balance model based on dissolved inorganic nitrogen (DIN) for the …

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Social Distancing And Testing As Optimal Strategies Against The Spread Of Covid-19 In The Rio Grande Valley Of Texas, Kristina P. Vatcheva, Josef A. Sifuentes, Tamer Oraby, Jose Campo Maldonado, Timothy Huber, Cristina Villalobos Apr 2021

Social Distancing And Testing As Optimal Strategies Against The Spread Of Covid-19 In The Rio Grande Valley Of Texas, Kristina P. Vatcheva, Josef A. Sifuentes, Tamer Oraby, Jose Campo Maldonado, Timothy Huber, Cristina Villalobos

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

At the beginning of August 2020, the Rio Grande Valley (RGV) of Texas experienced a rapid increase of coronavirus disease 2019 (abbreviated as COVID-19) cases and deaths. This study aims to determine the optimal levels of effective social distancing and testing to slow the virus spread at the outset of the pandemic. We use an age-stratified eight compartment epidemiological model to depict COVID-19 transmission in the community and within households. With a simulated 120-day outbreak period data we obtain a post 180-days period optimal control strategy solution. Our results show that easing social distancing between adults by the end of …

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Potential Ecological Impacts Of Climate Intervention By Reflecting Sunlight To Cool Earth, Phoebe L. Zarnetske, Jessica Gurevitch, Janet Franklin, Peter M. Groffman, Cheryl S. Harrison, Jessica J. Hellmann, Forrest M. Hoffman, Shan Kothari, Alan Robock, Simone Tilmes Apr 2021

Potential Ecological Impacts Of Climate Intervention By Reflecting Sunlight To Cool Earth, Phoebe L. Zarnetske, Jessica Gurevitch, Janet Franklin, Peter M. Groffman, Cheryl S. Harrison, Jessica J. Hellmann, Forrest M. Hoffman, Shan Kothari, Alan Robock, Simone Tilmes

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

As the effects of anthropogenic climate change become more severe, several approaches for deliberate climate intervention to reduce or stabilize Earth’s surface temperature have been proposed. Solar radiation modification (SRM) is one potential approach to partially counteract anthropogenic warming by reflecting a small proportion of the incoming solar radiation to increase Earth’s albedo. While climate science research has focused on the predicted climate effects of SRM, almost no studies have investigated the impacts that SRM would have on ecological systems. The impacts and risks posed by SRM would vary by implementation scenario, anthropogenic climate effects, geographic region, and by ecosystem, …

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A High-Precision Sar Echo Simulation Method Based On Fdtd, Bin Zou, Yanqiu Jia, Zhijun Qiao Apr 2021

A High-Precision Sar Echo Simulation Method Based On Fdtd, Bin Zou, Yanqiu Jia, Zhijun Qiao

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Synthetic aperture radar (SAR) echo simulation offers a low-cost and convenient way to obtain high-resolution images of targets, and plays an important role in system design and algorithm validation. Although high frequency approximation simulation is widely used, it is considered to be imprecise when calculating scattering field of fine structures, such as exhaust pipes and groove structures, especially in low frequency band. In this paper, a finite-difference time-domain (FDTD) based method is proposed for high-precision SAR echo simulation. In this method, scattering process of electromagnetic wave is accurately simulated to obtain equivalent electric and magnetic current on the surface of …

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Road Network Detection Based On Improved Flicm-Mrf Method Using High Resolution Sar Images, Lamei Zhang, Chenwei Jiang, Bin Zou, Zhijun Qiao Apr 2021

Road Network Detection Based On Improved Flicm-Mrf Method Using High Resolution Sar Images, Lamei Zhang, Chenwei Jiang, Bin Zou, Zhijun Qiao

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

The automatic detection of road network from satellite and aerial images is highly significant in many actual applications, for instance, urban traffic measurement, military emergency response, and vehicle target tracking. Compared with other high-resolution satellite remote sensing images, high-resolution synthetic aperture radar (SAR) has become a popular research perspective for road detection owing to its insensitivity to the atmosphere and sun-illumination. However, the method of road network detection is still lagging due to the strong multiplicative speckle noise and complex background interference, causing the loss and break in the road segment extraction results. Aiming to solve this problem, a three-step …

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The Salas Y Gómez And Nazca Ridges: A Review Of The Importance, Opportunities And Challenges For Protecting A Global Diversity Hotspot On The High Seas, Daniel Wagner, Liesbeth Van Der Meer, Matthias Gorny, Javier Sellanes, Carlos F. Gaymer, Eulogio H. Soto, Erin E. Easton, Alan M. Friedlander, Dhugal J. Lindsay, Tina N. Molodtsova Apr 2021

The Salas Y Gómez And Nazca Ridges: A Review Of The Importance, Opportunities And Challenges For Protecting A Global Diversity Hotspot On The High Seas, Daniel Wagner, Liesbeth Van Der Meer, Matthias Gorny, Javier Sellanes, Carlos F. Gaymer, Eulogio H. Soto, Erin E. Easton, Alan M. Friedlander, Dhugal J. Lindsay, Tina N. Molodtsova

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The Salas y Gómez and Nazca ridges are two seamount chains of volcanic origin, which include over 110 seamounts that collectively stretch across over 2,900 km in the southeastern Pacific. Ecosystems in this region are isolated by the Atacama Trench, the Humboldt Current System, and an extreme oxygen minimum zone. This isolation has produced a unique biodiversity that is marked by one of the highest levels of marine endemism on Earth. These areas also provide important habitats and ecological stepping stones for whales, sea turtles, corals, and a multitude of other ecologically important species, including 82 species that are threatened …

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On Problems With Weighted Elliptic Operator And General Growth Nonlinearities, John Villavert Apr 2021

On Problems With Weighted Elliptic Operator And General Growth Nonlinearities, John Villavert

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

This article establishes existence, non-existence and Liouville-type theorems for nonlinear equations of the form −div(|x| aDu) = f(x, u), u > 0, in Ω, where N ≥ 3, Ω is an open domain in R N containing the origin, N−2+a > 0 and f satisfies structural conditions, including certain growth properties. The first main result is a non-existence theorem for boundary-value problems in bounded domains star-shaped with respect to the origin, provided f exhibits supercritical growth. A consequence of this is the existence of positive entire solutions to the equation for f exhibiting the same growth. A Liouville-type theorem is then established, …

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Polymer Based Triboelectric Nanogenerator For Cost‐Effective Green Energy Generation And Implementation Of Surface‐Charge Engineering, Diana Lopez, Aminur Rashid Chowdhury, Abu Masa Abdullah, Muhtasim Ul Karim Sadaf, Isaac Martinez, Brishty Deb Chowdhury, Serena Danti, Christopher J. Ellison, Karen Lozano, Mohammed Jasim Uddin Mar 2021

Polymer Based Triboelectric Nanogenerator For Cost‐Effective Green Energy Generation And Implementation Of Surface‐Charge Engineering, Diana Lopez, Aminur Rashid Chowdhury, Abu Masa Abdullah, Muhtasim Ul Karim Sadaf, Isaac Martinez, Brishty Deb Chowdhury, Serena Danti, Christopher J. Ellison, Karen Lozano, Mohammed Jasim Uddin

Chemistry Faculty Publications and Presentations

Performance of triboelectric nanogenerators for harvesting mechanical energy from the ambient environment has been limited by structural complexity, cost-effectiveness, and mechanical weakness of materials. Herein, a cost-effective vertical contact separation mode triboelectric nanogenerator using polyethylene (PE) and polycarbonate (PC) in a regular digital versatile disc is reported. This cost-effective nanogenerator with simplified structures is able to generate an open-circuit voltage of 215.3 V and short-circuit current of 80 μA. The effects of the distance of impact and the air gap between the triboelectric layers have also been tested from 3 to 9 cm, and 0.25 to 1 cm, respectively. It …

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Antioxidant Properties Of Pecan Shell Bioactive Components Of Different Cultivars And Extraction Methods, Cameron Cason, Veerachandra K. Yemmireddy, Juan Moreira, Achyut Adhikari Mar 2021

Antioxidant Properties Of Pecan Shell Bioactive Components Of Different Cultivars And Extraction Methods, Cameron Cason, Veerachandra K. Yemmireddy, Juan Moreira, Achyut Adhikari

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Pecan shells are a rich source of various bioactive compounds with potential antioxidant and antimicrobial properties. This study investigated the effect of pecan variety and method extraction on the antioxidant property of shell extracts. Twenty different varieties of pecan shells were subjected to either aqueous or ethanolic extraction and were examined for total phenolics and antiradical activity. The phenolic content and antiradical activity of shell extracts were significantly (p < 0.05) varied with different pecan cultivars. The total phenolic content of ethanol extracts ranged from 304.2 (Caddo) to 153.54 (Cherokee) mg GAE/g of dry extract and was significantly greater (p < 0.05) than those obtained by aqueous extraction. The antiradical activity of ethanol extracts ranged from 840.6 (Maramec) to 526.74 (Caper Fear) mg TEg−1, while aqueous extracts ranged from 934.9 (Curtis) to 468.3 (Elliot) mg TEg−1. Chemical profiling of the crude and acid hydrolyzed extracts was performed by reverse phase high performance liquid chromatography and flow injection electrospray ionization mass spectrometry. Lignin degradation products such as lignols, dilignols, trilignols, and oligolignols were found to be the major components of tested extracts. Phenolic content and antiradical activity of pecan shell extracts are significantly varied with cultivars and methods of extraction.

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Lions-Type Theorem Of The P-Laplacian And Applications, Yu Su, Zhaosheng Feng Mar 2021

Lions-Type Theorem Of The P-Laplacian And Applications, Yu Su, Zhaosheng Feng

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

In this article, our aim is to establish a generalized version of Lions-type theorem for the p-Laplacian. As an application of this theorem, we consider the existence of ground state solution for the quasilinear elliptic equation with the critical growth.

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Common-Spectrum Process Versus Cross-Correlation For Gravitational-Wave Searches Using Pulsar Timing Arrays, Joseph D. Romano, ‪Jeffrey S. Hazboun, X. Siemens, Anne M. Archibald Mar 2021

Common-Spectrum Process Versus Cross-Correlation For Gravitational-Wave Searches Using Pulsar Timing Arrays, Joseph D. Romano, ‪Jeffrey S. Hazboun, X. Siemens, Anne M. Archibald

Physics and Astronomy Faculty Publications and Presentations

The North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has recently reported strong statistical evidence for a common-spectrum red-noise process for all pulsars, as seen in their 12.5-yr analysis for an isotropic stochastic gravitational-wave signal. However, there is currently very little evidence for quadrupolar spatial correlations across the pulsars in the array, which is needed to make a confident claim of detection of a stochastic gravitational-wave background. In this paper, we provide a “back-of-the-envelope” illustration of the NANOGrav 12.5-yr results for the nonexpert reader, using a very simple signal+noise model and frequentist statistics. We show that the current lack of …

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First Description Of Deep Benthic Habitats And Communities Of Oceanic Islands And Seamounts Of The Nazca Desventuradas Marine Park, Chile, Jan M. Tapia-Guerra, Ariadna Mecho, Erin E. Easton, María De Los Ángeles Gallardo, Matthias Gorny, Javier Sellanes Mar 2021

First Description Of Deep Benthic Habitats And Communities Of Oceanic Islands And Seamounts Of The Nazca Desventuradas Marine Park, Chile, Jan M. Tapia-Guerra, Ariadna Mecho, Erin E. Easton, María De Los Ángeles Gallardo, Matthias Gorny, Javier Sellanes

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Seamounts and oceanic islands of the Chilean Exclusive Economic Zone at the intersection of the Nazca and Salas y Gómez ridges lie within one of the least explored areas in the world. The sparse information available, mainly for seamounts outside Chilean jurisdiction and shallow-water fauna of the Desventuradas Islands, suggests that the area is a hotspot of endemism. This apparent uniqueness of the fauna motivated the creation of the large Nazca-Desventuradas Marine Park (NDMP, ~ 300,000 km2) around the small islands San Felix and San Ambrosio in 2015. We report for the first time a detailed description of benthic microhabitats …

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Frequentist Versus Bayesian Analyses: Cross-Correlation As An Approximate Sufficient Statistic For Ligo-Virgo Stochastic Background Searches, Andrew Matas, Joseph D. Romano Mar 2021

Frequentist Versus Bayesian Analyses: Cross-Correlation As An Approximate Sufficient Statistic For Ligo-Virgo Stochastic Background Searches, Andrew Matas, Joseph D. Romano

Physics and Astronomy Faculty Publications and Presentations

Sufficient statistics are combinations of data in terms of which the likelihood function can be rewritten without loss of information. Depending on the data volume reduction, the use of sufficient statistics as a preliminary step in a Bayesian analysis can lead to significant increases in efficiency when sampling from posterior distributions of model parameters. Here we show that the frequency integrand of the cross-correlation statistic and its variance are approximate sufficient statistics for ground-based searches for stochastic gravitational-wave backgrounds. The sufficient statistics are approximate because one works in the weak-signal approximation and uses measured estimates of the autocorrelated power in …

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All-Sky Search In Early O3 Ligo Data For Continuous Gravitational-Wave Signals From Unknown Neutron Stars In Binary Systems, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, K. E. Ramirez, W. H. Wang Mar 2021

All-Sky Search In Early O3 Ligo Data For Continuous Gravitational-Wave Signals From Unknown Neutron Stars In Binary Systems, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, K. E. Ramirez, W. H. Wang

Physics and Astronomy Faculty Publications and Presentations

Rapidly spinning neutron stars are promising sources of continuous gravitational waves. Detecting such a signal would allow probing of the physical properties of matter under extreme conditions. A significant fraction of the known pulsar population belongs to binary systems. Searching for unknown neutron stars in binary systems requires specialized algorithms to address unknown orbital frequency modulations. We present a search for continuous gravitational waves emitted by neutron stars in binary systems in early data from the third observing run of the Advanced LIGO and Advanced Virgo detectors using the semicoherent, GPU-accelerated, BinarySkyHough pipeline. The search analyzes the most sensitive frequency …

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A Gravitational-Wave Measurement Of The Hubble Constant Following The Second Observing Run Of Advanced Ligo And Virgo, B. P. Abbott, R. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, K. E. Ramirez, Satzhan Sitmukhambetov, Robert Stone, D. Tuyenbayev, W. H. Wang, Adam Zadrozny Mar 2021

A Gravitational-Wave Measurement Of The Hubble Constant Following The Second Observing Run Of Advanced Ligo And Virgo, B. P. Abbott, R. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, K. E. Ramirez, Satzhan Sitmukhambetov, Robert Stone, D. Tuyenbayev, W. H. Wang, Adam Zadrozny

Physics and Astronomy Faculty Publications and Presentations

This paper presents the gravitational-wave measurement of the Hubble constant (H0) using the detections from the first and second observing runs of the Advanced LIGO and Virgo detector network. The presence of the transient electromagnetic counterpart of the binary neutron star GW170817 led to the first standard-siren measurement of H0. Here we additionally use binary black hole detections in conjunction with galaxy catalogs and report a joint measurement. Our updated measurement is H0 = - 69+8 16 km s−1 Mpc−1 (68.3% of the highest density posterior interval with a flat-in-log prior) which is an improvement by a factor of 1.04 …

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Influence Of Microbial Priming And Seeding Depth On Germination And Growth Of Native Wildflowers, Daniela Barrera, Juan Luera, Kaitlynn Lavallee, Pushpa Soti Mar 2021

Influence Of Microbial Priming And Seeding Depth On Germination And Growth Of Native Wildflowers, Daniela Barrera, Juan Luera, Kaitlynn Lavallee, Pushpa Soti

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Background: Using native wildflowers for restoring marginal lands has gained considerable popularity. Establishment of wildflowers can be challenging due to several environmental factors. Restoring the microbial community in degraded habitats can potentially result in the native plant performance and habitat restoration. This study was conducted to investigate the impact of native soil microbes and seeding depth on germination of south Texas native wildflowers. Two wildflower species, Ratibida columnifera (Nutt.) (Mexican Hat) and Verbesina encelioides (Cav.) (cowpen daisy), were treated with microbial wash extracted from native soils, and germination rate was recorded for 14-day period. We further analyzed the growth, biomass …

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Environmental Forcing On Zooplankton Distribution In The Coastal Waters Of The Galápagos Islands: Spatial And Seasonal Patterns In The Copepod Community Structure, Diego F. Figueroa Mar 2021

Environmental Forcing On Zooplankton Distribution In The Coastal Waters Of The Galápagos Islands: Spatial And Seasonal Patterns In The Copepod Community Structure, Diego F. Figueroa

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The oceanographic setting of the Galápagos Archipelago results in a spatially diverse marine environment suitable for a variety of species with different climatic requirements. The goal of this study is to demonstrate that the community of zooplankton in the Galápagos is highly structured by regional differences in productivity patterns and advective sources. Results are mostly based on biodiversity patterns of the copepod community collected over the Galápagos shelf between 2004 and 2006. Two contrasting marine environments were observed: a nutrientrich upwelling system with a shallow mixed layer and a diatom-dominated phytoplankton community in the west, and a non-upwelling system with …

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Effect Of Genotype On The Physicochemical, Nutritional, And Antioxidant Properties Of Hempseed, Youjie Xu, Jikai Zhao, Ruijia Hu, Weiqun Wang, Jason Griffin, Yonghui Li, Xiuzhi Susan Sun, Donghai Wang Mar 2021

Effect Of Genotype On The Physicochemical, Nutritional, And Antioxidant Properties Of Hempseed, Youjie Xu, Jikai Zhao, Ruijia Hu, Weiqun Wang, Jason Griffin, Yonghui Li, Xiuzhi Susan Sun, Donghai Wang

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Hempseed products has been used as nutraceutical supplements and pharmaceutical products. However, hempseed has been underutilized as a food crop for human consumption. To fill the gap of limited knowledge of the variation of hempseed for food consumption, thirteen hemp varieties were selected to evaluate the effect of genotype on the physicochemical, nutritional, and antioxidant properties of hempseed. The tested hempseed contains 26.48–32.03% crude protein with average of 28.48%, 28.03–33.23% crude oil with average of 29.54%, 28.78–36.55% crude fiber with average of 33.49%, and 5.43%–6.32% ash with average of 5.89. Average test weight of 36.85 lbs/bu was relatively low compared …

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Continuous-Time Controlled Branching Processes, Ines Garcia, George Yanev, Manuel Molina, Nikolay Yanev, Miguel Velasco Mar 2021

Continuous-Time Controlled Branching Processes, Ines Garcia, George Yanev, Manuel Molina, Nikolay Yanev, Miguel Velasco

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Controlled branching processes with continuous time are introduced and limiting distributions are obtained in the critical case. An extension of this class as regenerative controlled branching processes with continuous time is proposed and some asymptotic properties are considered.

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Eigenvalues And Eigenfunctions Of A Schrödinger Operator Associated With A Finite Combination Of Dirac-Delta Functions And Ch Peakons, Shouzhong Fu, Zhijun Qiao, Zhong Wang Mar 2021

Eigenvalues And Eigenfunctions Of A Schrödinger Operator Associated With A Finite Combination Of Dirac-Delta Functions And Ch Peakons, Shouzhong Fu, Zhijun Qiao, Zhong Wang

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

In this paper, we first study the Schrodinger operators with the following weighted function ___________, which is actually a finite linear combination of Dirac-Delta functions, and then discuss the same operator equipped with the same kind of potential function. With the aid of the boundary conditions, all possible eigenvalues and eigenfunctions of the self-adjoint Schrodinger operator are investigated. Furthermore, as a practical application, the spectrum distribution of such a Dirac-Delta type Schrodinger operator either weighted or potential is well applied to the remarkable integrable Camassa-Holm (CH) equation.

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Correlation Between No-Slip And Slip Boundary Conditions Associated With A Two-Dimensional Navier-Stokes Flows In A Plane Diffuser, Ranis Ibragimov, Vesselin Vatchev Mar 2021

Correlation Between No-Slip And Slip Boundary Conditions Associated With A Two-Dimensional Navier-Stokes Flows In A Plane Diffuser, Ranis Ibragimov, Vesselin Vatchev

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

We examine the viscous effects of slip boundary conditions for the model describing two-dimensional Navier-Stokes flows in a plane diffuser. It is shown that the velocity profile is related to a half period shifted Weierstrass function with two parameters. This allows to approximate the explicit solution by a Taylor series expansion with two new micro- parameters, that can be measured in physical experiments. It is shown that the assumption for no-slip boundary conditions is stable in the sense that a small perturbation of the boundary values result in a small perturbation in the solutions.

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Multifunctional Conductive Paths Obtained By Laser Processing Of Non-Conductive Carbon Nanotube/Polypropylene Composites, Federico Cesano, Mohammed Jasim Uddin, Alessandro Damin, Domenica Scarano Feb 2021

Multifunctional Conductive Paths Obtained By Laser Processing Of Non-Conductive Carbon Nanotube/Polypropylene Composites, Federico Cesano, Mohammed Jasim Uddin, Alessandro Damin, Domenica Scarano

Chemistry Faculty Publications and Presentations

Functional materials are promising candidates for application in structural health monitoring/self-healing composites, wearable systems (smart textiles), robotics, and next-generation electronics. Any improvement in these topics would be of great relevance to industry, environment, and global needs for energy sustainability. Taking into consideration all these aspects, low-cost fabrication of electrical functionalities on the outer surface of carbon-nanotube/polypropylene composites is presented in this paper. Electrical-responsive regions and conductive tracks, made of an accumulation layer of carbon nanotubes without the use of metals, have been obtained by the laser irradiation process, leading to confined polymer melting/vaporization with consequent local increase of the nanotube …

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Robust Inference Of Kinase Activity Using Functional Networks, Serhan Yılmaz, Marzieh Ayati, Daniela Schlatzer, A. Ercüment Çiçek, Mark A. Chance, Mehmet Koyutürk Feb 2021

Robust Inference Of Kinase Activity Using Functional Networks, Serhan Yılmaz, Marzieh Ayati, Daniela Schlatzer, A. Ercüment Çiçek, Mark A. Chance, Mehmet Koyutürk

Computer Science Faculty Publications and Presentations

Mass spectrometry enables high-throughput screening of phosphoproteins across a broad range of biological contexts. When complemented by computational algorithms, phospho-proteomic data allows the inference of kinase activity, facilitating the identification of dysregulated kinases in various diseases including cancer, Alzheimer’s disease and Parkinson’s disease. To enhance the reliability of kinase activity inference, we present a network-based framework, RoKAI, that integrates various sources of functional information to capture coordinated changes in signaling. Through computational experiments, we show that phosphorylation of sites in the functional neighborhood of a kinase are significantly predictive of its activity. The incorporation of this knowledge in RoKAI consistently …

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A Secure And Flexible Fpga–Based Blockchain System For Iiots, Han-Yee Kim, Lei Xu, Weidong Shi, Taeweon Suh Feb 2021

A Secure And Flexible Fpga–Based Blockchain System For Iiots, Han-Yee Kim, Lei Xu, Weidong Shi, Taeweon Suh

Computer Science Faculty Publications and Presentations

Blockchain is a promising solution for Industry 4.0 due to its traceability and immutability. However, blockchain itself does not guarantee the input data integrity. The tampered data from an endpoint device can be a significant problem because it may result in a cascaded negative effect on the whole smart factory operations. In this paper, we propose an FPGA-based private blockchain system for IIoTs, where the transaction generation is performed inside the FPGA in an isolated and enclaved manner. For the key confidentiality and transaction integrity, the proposed system utilizes a PUF, soft processor, and tightly coupled sensor connections inside the …

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Modeling The Effect Of Lockdown Timing As A Covid‑19 Control Measure In Countries With Differing Social Contacts, Tamer Oraby, Michael G. Tyshenko, Jose Campo Maldonado, Kristina Vatcheva, Susie Elsaadany, Walid Q. Alali, Joseph C. Longenecker, Mustafa Al‑Zoughool Feb 2021

Modeling The Effect Of Lockdown Timing As A Covid‑19 Control Measure In Countries With Differing Social Contacts, Tamer Oraby, Michael G. Tyshenko, Jose Campo Maldonado, Kristina Vatcheva, Susie Elsaadany, Walid Q. Alali, Joseph C. Longenecker, Mustafa Al‑Zoughool

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

The application, timing, and duration of lockdown strategies during a pandemic remain poorly quantified with regards to expected public health outcomes. Previous projection models have reached conflicting conclusions about the effect of complete lockdowns on COVID-19 outcomes. We developed a stochastic continuous-time Markov chain (CTMC) model with eight states including the environment (SEAMHQRD-V), and derived a formula for the basic reproduction number, R0, for that model. Applying the R 0 formula as a function in previously-published social contact matrices from 152 countries, we produced the distribution and four categories of possible R 0 for the 152 countries and chose one …

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