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University of Texas Rio Grande Valley

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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 & Statistical Sciences Faculty Publications

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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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 & Statistical Sciences Faculty Publications

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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Two-Year Responses Of Heart Rate And Heart Rate Variability To First Occupational Lead Exposure, Yuling Yu, Lutgarde Thijs, Cai-Guo Yu, Wenyi Yang, Jesus D. Melgarejo, Dongmei Wei, Fangfei Wei, Tim S. Nawrot, Peter Verhamme, Harry Roels May 2021

Two-Year Responses Of Heart Rate And Heart Rate Variability To First Occupational Lead Exposure, Yuling Yu, Lutgarde Thijs, Cai-Guo Yu, Wenyi Yang, Jesus D. Melgarejo, Dongmei Wei, Fangfei Wei, Tim S. Nawrot, Peter Verhamme, Harry Roels

School of Medicine Publications

Because of the falling lead exposure, the literature relating autonomous nervous function to blood lead (BL) has limited relevance. In the longitudinal Study for Promotion of Health in Recycling Lead (URL: https://www.clinicaltrials.gov; Unique identifier: NCT02243904), we recorded the 2-year responses of heart rate (HR), HR variability (HRV; Cardiax, International Medical Equipment Developing, Budapest, Hungary), and median nerve conduction velocity (Brevio, NeuMed, West Trenton, NJ), a routine test in occupational medicine, to first lead exposure in 195 newly hired workers (91.3% men; mean age, 27.8 years). High- and low-frequency HRV power and orthostatic HRV responses were derived from 5-minute ECGs …

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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

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

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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The Rider (2021-04-26), Jacqueline Peraza Apr 2021

The Rider (2021-04-26), Jacqueline Peraza

The Rider Archives

Vol.6 No.28

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Spectral Singularities With Directional Sensitivity, Hamidreza Ramezani Apr 2021

Spectral Singularities With Directional Sensitivity, Hamidreza Ramezani

Physics & Astronomy Faculty Publications

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, & Marine Sciences Faculty Publications

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 E. 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 E. Campo Maldonado, Timothy Huber, Cristina Villalobos

School of Mathematical & Statistical Sciences Faculty Publications

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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Greenhouse Gas Emission Inefficiency Spillover Effects In European Countries, Levent Kutlu, Ran Wang Apr 2021

Greenhouse Gas Emission Inefficiency Spillover Effects In European Countries, Levent Kutlu, Ran Wang

School of Economics and Finance Faculty Publications

In our study, we examine whether spatial spillover effects exist for greenhouse gas emission efficiency for 38 European countries between 2005 and 2014. We find that inefficiencies of other countries would lead to lower efficiency levels for a country. This negative inefficiency spillover effect goes down till 2008 then goes up till 2011, then stays relatively stable after 2011. Any strategy to reduce inefficiencies of other countries could potentially improve the efficiency levels. We find that human development index shows significant positive impact on greenhouse gas emission efficiency levels. In particular, one standard deviation increase in human development index would …

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Pinta: The Ugmrt Data Processing Pipeline For The Indian Pulsar Timing Array, Abhimanyu Susobhanan, Yogesh Maan, Bhal Chandra Joshi, T. Prabu, Shantanu Desai, K. Nobleson, Sai Chaitanya Susarla, Raghav Girgaonkar, Lankeswar Dey, Suryarao Bethapudi Apr 2021

Pinta: The Ugmrt Data Processing Pipeline For The Indian Pulsar Timing Array, Abhimanyu Susobhanan, Yogesh Maan, Bhal Chandra Joshi, T. Prabu, Shantanu Desai, K. Nobleson, Sai Chaitanya Susarla, Raghav Girgaonkar, Lankeswar Dey, Suryarao Bethapudi

Physics & Astronomy Faculty Publications

We introduce pinta, a pipeline for reducing the upgraded Giant Metre-wave Radio Telescope (uGMRT) raw pulsar timing data, developed for the Indian Pulsar Timing Array experiment. We provide a detailed description of the workflow and usage of pinta, as well as its computational performance and RFI mitigation characteristics. We also discuss a novel and independent determination of the relative time offsets between the different back-end modes of uGMRT and the interpretation of the uGMRT observation frequency settings and their agreement with results obtained from engineering tests. Further, we demonstrate the capability of pinta to generate data products which can produce …

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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, & Marine Sciences Faculty Publications

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 & Statistical Sciences Faculty Publications

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 & Statistical Sciences Faculty Publications

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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Pint: A Modern Software Package For Pulsar Timing, Jing Luo, S. M. Ransom, Paul B. Demorest, P. S. Ray, Anne M. Archibald, M. Kerr, Ross J. Jennings, Matteo Bachetti, Rutger Van Haasteren, Fredrick A. Jenet Apr 2021

Pint: A Modern Software Package For Pulsar Timing, Jing Luo, S. M. Ransom, Paul B. Demorest, P. S. Ray, Anne M. Archibald, M. Kerr, Ross J. Jennings, Matteo Bachetti, Rutger Van Haasteren, Fredrick A. Jenet

Physics & Astronomy Faculty Publications

Over the past few decades, the measurement precision of some pulsar timing experiments has advanced from ~10 μs to ~10 ns, revealing many subtle phenomena. Such high precision demands both careful data handling and sophisticated timing models to avoid systematic error. To achieve these goals, we present PINT (PINT Is Not Tempo3), a high-precision Python pulsar timing data analysis package, which is hosted on GitHub and available on the Python Package Index (PyPI) as pint-pulsar. PINT is well tested, validated, object oriented, and modular, enabling interactive data analysis and providing an extensible and flexible development platform for timing applications. …

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Using The Schmahmann Syndrome Scale To Assess Cognitive Impairment In Young Adults With Metabolic Syndrome: A Hypothesis-Generating Report, Eithan Kotkowski, Larry R. Price, Cheasequah J. Blevins, Crystal Franklin, Mary Woolsey, Ralph A. Defronzo, John Blangero, Ravindranath Duggirala, David C. Glahn, Jeremy Schmahmann, Peter T. Fox Apr 2021

Using The Schmahmann Syndrome Scale To Assess Cognitive Impairment In Young Adults With Metabolic Syndrome: A Hypothesis-Generating Report, Eithan Kotkowski, Larry R. Price, Cheasequah J. Blevins, Crystal Franklin, Mary Woolsey, Ralph A. Defronzo, John Blangero, Ravindranath Duggirala, David C. Glahn, Jeremy Schmahmann, Peter T. Fox

School of Medicine Publications

The posterior cerebellum is the most significantly compromised brain structure in individuals with metabolic syndrome (MetS) (Kotkowski et al., 2019). In light of this, we hypothesized that cognitive decline reported in patients with MetS is likely related to posterior cerebellar atrophy. In this study, we performed a post-hoc analyses using T1-weighted magnetic resonance imaging (MRI), diffusion tensor imaging (DTI) in the form of voxel-wise tract-based spatial statistics (TBSS), biometric, and psychometric data from young participants with (n = 52, aged 18–35 years) and without MetS (n = 52, aged 18–35 years). To test the predictive value of components …

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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, & Marine Sciences Faculty Publications

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 & Statistical Sciences Faculty Publications

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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Modeling Through Model-Eliciting Activities: An Analysis Of Models, Elements, And Strategies In High School. The Cases Of Students With Different Level Of Achievement, Jair J. Aguilar Apr 2021

Modeling Through Model-Eliciting Activities: An Analysis Of Models, Elements, And Strategies In High School. The Cases Of Students With Different Level Of Achievement, Jair J. Aguilar

Teaching and Learning Faculty Publications

A mathematical client-driven task known as Model-Eliciting Activities was implemented with students of different levels of achievement (i.e., low, average, and high) at the high-school level. The study strived to prove that Model-Eliciting Activities can be solved by students at any achievement level and be used as an assessment tool. Students collaborated in teams of three to develop solutions that met the client’s needs. The model-solutions were compared and contrasted among several dimensions and achievement levels, considering the quality of the final product-solution based on the Quality Assessment Guide, the intermedia product composed of the type of models created, the …

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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

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

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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Exhpd: Exploiting Human, Physical, And Driving Behaviors To Detect Vehicle Cyber Attacks, Qian Chen, Paul Romanowich, Jorge Castillo, Krishna Chandra Roy, Gustavo Chavez, Shouhuai Xu Mar 2021

Exhpd: Exploiting Human, Physical, And Driving Behaviors To Detect Vehicle Cyber Attacks, Qian Chen, Paul Romanowich, Jorge Castillo, Krishna Chandra Roy, Gustavo Chavez, Shouhuai Xu

Informatics and Engineering Systems Faculty Publications

As increasingly more vehicles are connected to the Internet, cyber attacks against vehicles are becoming a real threat with devastating consequences. This highlights the importance of detecting vehicle cyber attacks before fatal accidents occur. One natural method for tackling this problem is to adapt existing approaches for detecting attacks in enterprize networks, but which has achieved limited success. In this article, we propose a new approach to treat vehicles as cyber-physical-human systems, leading to a novel framework called exploiting human, physical and driving behaviors to detect vehicle cyber attacks (ExHPD). The framework has four detectors: 1) a human detector; 2) …

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Planning Our Lessons, Joy Esquierdo Mar 2021

Planning Our Lessons, Joy Esquierdo

Spring Workshop March 2021

No abstract provided.

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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, & Marine Sciences Faculty Publications

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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Feasibility Of Using A High-Power Electromagnetic Energy Harvester To Power Structural Health Monitoring Sensors And Systems In Transportation Infrastructures, Mohsen Amjadian, Anil K. Agrawal, Hani Nassif Mar 2021

Feasibility Of Using A High-Power Electromagnetic Energy Harvester To Power Structural Health Monitoring Sensors And Systems In Transportation Infrastructures, Mohsen Amjadian, Anil K. Agrawal, Hani Nassif

Civil Engineering Faculty Publications

This paper investigates the feasibility of an electromagnetism energy harvester (EMEH) for scavenging electric energy from transportation infrastructures and powering of conventional sensors used for their structural health monitoring. The proposed EMEH consists of two stationary layers of three cuboidal permanent magnets (PMs), a rectangular thick aircore copper coil (COIL) attached to the free end of a flexible cantilever beam whose fixed end is firmly attached to the highway bridge oscillating in the vertical motion due to passing traffic. The proposed EMEH utilizes the concept of creating an alternating array of permanent magnets to achieve strong and focused magnetic field …

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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 & Statistical Sciences Faculty Publications

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 & Astronomy Faculty Publications

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, & Marine Sciences Faculty Publications

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 & Astronomy Faculty Publications

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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Robust, Flexible, And Scalable Tests For Hardy-Weinberg Equilibrium Across Diverse Ancestries, Alan M. Kwong, Thomas W. Blackwell, Jonathon Lefaive, Mariza De Andrade, John Barnard, Kathleen C. Barnes, John Blangero Mar 2021

Robust, Flexible, And Scalable Tests For Hardy-Weinberg Equilibrium Across Diverse Ancestries, Alan M. Kwong, Thomas W. Blackwell, Jonathon Lefaive, Mariza De Andrade, John Barnard, Kathleen C. Barnes, John Blangero

School of Medicine Publications

Traditional Hardy-Weinberg equilibrium (HWE) tests (the χ2 test and the exact test) have long been used as a metric for evaluating genotype quality, as technical artifacts leading to incorrect genotype calls often can be identified as deviations from HWE. However, in datasets comprised of individuals from diverse ancestries, HWE can be violated even without genotyping error, complicating the use of HWE testing to assess genotype data quality. In this manuscript, we present the Robust Unified Test for HWE (RUTH) to test for HWE while accounting for population structure and genotype uncertainty, and evaluate the impact of population heterogeneity and genotype …

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Representations Of Principal W-Algebra For The Superalgebra Q(N) And The Super Yangian Yq(1), Elena Poletaeva, Vera Serganova Mar 2021

Representations Of Principal W-Algebra For The Superalgebra Q(N) And The Super Yangian Yq(1), Elena Poletaeva, Vera Serganova

School of Mathematical & Statistical Sciences Faculty Publications

We classify irreducible representations of finite W-algebra for the queer Lie superalgebra Q(n) associated with the principal nilpotent coadjoint orbits. We use this classification and our previous results to obtain a classification of irreducible finite-dimensional representations of the super Yangian YQ(1).

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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 & Astronomy Faculty Publications

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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