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Secondary School State Athletic Association Health And Safety Policy Development Processes, Susan Yeargin, Rebecca M. Hirschhorn, William M. Adams, Samantha E. Scarneo-Miller Jul 2024

Secondary School State Athletic Association Health And Safety Policy Development Processes, Susan Yeargin, Rebecca M. Hirschhorn, William M. Adams, Samantha E. Scarneo-Miller

Faculty Publications

Background: The National Federation of State High School Associations provides recommendations regarding health and safety policies; however, policy development is governed at the state level. Given interstate differences in governance, the primary purpose was to describe processes that State High School Athletic Associations (SHSAAs) utilize to develop a new policy. The secondary objective was to determine what methods associations use to implement new policies. Methods: A cross-sectional survey requested SHSAA (n = 51) representatives to report how athlete health and safety policies are introduced, revised, approved, and implemented within their state. The 22-question survey was developed to gather variables for …


Snapshots Of Coastal Ecology Using Multiproxy Analysis Reveals Insights Into The Preservation Of Swamp And Marsh Environments Since The Late Pleistocene, Kendall Fontenot, Kristine L. Delong, Brian A. Schubert, Sophie Warny, Davin J. Wallace, Carrie M. Miller, Erin Culver-Miller, Michael J. Polito, Carl A. Reese, Kathryn Garretson, Kehui Xu, Grant L. Harley, Jeffrey Obelcz, Kelli L. Moran, Julian Traphagan, Douglas Jones, Alicia Caporaso Jul 2024

Snapshots Of Coastal Ecology Using Multiproxy Analysis Reveals Insights Into The Preservation Of Swamp And Marsh Environments Since The Late Pleistocene, Kendall Fontenot, Kristine L. Delong, Brian A. Schubert, Sophie Warny, Davin J. Wallace, Carrie M. Miller, Erin Culver-Miller, Michael J. Polito, Carl A. Reese, Kathryn Garretson, Kehui Xu, Grant L. Harley, Jeffrey Obelcz, Kelli L. Moran, Julian Traphagan, Douglas Jones, Alicia Caporaso

Faculty Publications

The southeastern United States Coastal Plain ecosystem contains baldcypress (Taxodium distichum) swamps and grass-dominated marshes. These ecosystems also occurred on the exposed continental shelf during lower sea levels but are rarely preserved due to the mechanically erosive nature of transgression and regression. Two presently marine sites on the northeastern Gulf of Mexico's continental shelf contain well-preserved woody terrestrial sediments that were the subject of previous studies. This study continues the investigation using geochemical (δ13C, δ15N, δ34S) and palynological characteristics of these formerly terrestrial sediments to determine if swamps and/or marshes existed at the time of deposition. The first site is …


Spatiotemporal Analysis Of Nighttime Crimes In Vienna, Austria, Jiyoung Lee, Michael Leitner, Gernot Paulus Jul 2024

Spatiotemporal Analysis Of Nighttime Crimes In Vienna, Austria, Jiyoung Lee, Michael Leitner, Gernot Paulus

Faculty Publications

Studying the spatiotemporal dynamics of crime is crucial for accurate crime geography research. While studies have examined crime patterns related to weekdays, seasons, and specific events, there is a noticeable gap in research on nighttime crimes. This study focuses on crimes occurring during the nighttime, investigating the temporal definition of nighttime crime and the correlation between nighttime lights and criminal activities. The study concentrates on four types of nighttime crimes, assault, theft, burglary, and robbery, conducting univariate and multivariate analyses. In the univariate analysis, correlations between nighttime crimes and nighttime light (NTL) values detected in satellite images and between streetlight …


A Simple Approach To Dealing With Partial Contestation, Ali Kagalwala, Thiago M.Q. Moreira, Guy D. Whitten Jul 2024

A Simple Approach To Dealing With Partial Contestation, Ali Kagalwala, Thiago M.Q. Moreira, Guy D. Whitten

Faculty Publications

Objective: We propose a simple approach to dealing with partial contestation in models of multiparty elections. Methods: Our proposed approach is to add a tiny value to the vote share of parties that do not contest a district and then to include dummy variables identifying those districts in which parties do not compete. We can then estimate a single system of equations using a seemingly unrelated regression (SUR) approach and Aitchison's log-ratio transformation. In our SUR system, we interact the dummy variable for a party that partially contested districts with other predictors in the equation that uses the share of …


A (Dynamic) Investigation Of Stereotypes, Belief-Updating, And Behavior, Katherine Coffman, Maria Paola Ugalde Araya, Basit Zafar Jul 2024

A (Dynamic) Investigation Of Stereotypes, Belief-Updating, And Behavior, Katherine Coffman, Maria Paola Ugalde Araya, Basit Zafar

Faculty Publications

Using a controlled experiment, we study the dynamic effects of feedback on decision-making across verbal skills and math. Before feedback, men are more optimistic about their performance and more willing to compete than women, especially in math. While feedback shifts individuals' beliefs and behavior, we see substantial persistence of gender gaps 1 week later. This is particularly true among individuals who receive negative feedback. Our results are not well-explained by motivated reasoning; in fact, negative feedback is more likely to be recalled than positive feedback. Overall, our results highlight the challenges involved in overcoming gender gaps in dynamic settings.


Presidential Stories Of Fear: Focusing Congressional Climate Change Mitigation Attention In The United States, Holly L. Peterson, Chad Zanocco Jul 2024

Presidential Stories Of Fear: Focusing Congressional Climate Change Mitigation Attention In The United States, Holly L. Peterson, Chad Zanocco

Faculty Publications

Do presidential climate change narratives increase related congressional attention in the United States? Narrative theory says since narratives leverage cognitive heuristics, they should focus policy-making attention in institutions more efficiently than non-narrative statements. This study identifies and tests climate change statements and narratives, including those focused on solutions, or “stories of hope,” and those focused on problems and victims, “stories of fear,” for relationships with congressional attention using time series analysis. Findings suggest a relationship between narrative and hearings, but not for non-narrative statements and hearings. Furthermore, while narratives are related to hearings generally, stories of fear have larger effects, …


The Expression Of Mantle Seismic Anisotropy In The Global Seismic Wavefield, Jonathan Wolf, Maureen D. Long, Daniel A. Frost, Tarje Nissen-Meyer Jul 2024

The Expression Of Mantle Seismic Anisotropy In The Global Seismic Wavefield, Jonathan Wolf, Maureen D. Long, Daniel A. Frost, Tarje Nissen-Meyer

Faculty Publications

The dependence of seismic wave speeds on propagation or polarization direction, called seismic anisotropy, is a relatively direct indicator of mantle deformation and flow. Mantle seismic anisotropy is often inferred from measurements of shear-wave splitting. A number of standard techniques to measure shear-wave splitting have been applied globally; for example, *KS splitting is often used to measure upper mantle anisotropy. In order to obtain robust constraints on anisotropic geometry, it is necessary to sample seismic anisotropy from different directions, ideally using different seismic phases with different incidence angles. However, many standard analysis techniques can only be applied for certain epicentral …


Water-Limited Hydrothermalism And Volcanic Resurfacing Of Eridania Basin, Mars, Emmy B. Hughes, James Wray, Suniti Karunatillake, Grace Fanson, Elise Harrington, Don R. Hood Jul 2024

Water-Limited Hydrothermalism And Volcanic Resurfacing Of Eridania Basin, Mars, Emmy B. Hughes, James Wray, Suniti Karunatillake, Grace Fanson, Elise Harrington, Don R. Hood

Faculty Publications

The Eridania Basin system, located in the martian southern highlands, may have hosted long-lived lacustrine hydrothermalism. Despite its multi-basin scale and suggested longevity that should pervasively alter the landscape, evidence for consistent compositional signatures of lacustrine hydrothermalism across varying spatial scales is poorly known. Here we synthesize orbital data sets (derived from the Gamma Ray Spectrometer, GRS; Thermal Emission Spectrometer, TES; and Compact Reconnaissance Imaging Spectrometer for Mars, CRISM) to characterize the composition of Eridania's landscape from regional to outcrop scales. The bulk geochemistry representing decimeter depths is broadly on par with mafic igneous compositions seen elsewhere on Mars. The …


Improving Asphalt Binder Durability Using Sustainable Materials: A Rheological And Chemical Analysis Of Polymer-, Rubber-, And Epoxy-Modified Asphalt Binders, Anas Abualia, Moses Akentuna, Louay N. Mohammad, Samuel B. Cooper, Samuel B. Cooper Jul 2024

Improving Asphalt Binder Durability Using Sustainable Materials: A Rheological And Chemical Analysis Of Polymer-, Rubber-, And Epoxy-Modified Asphalt Binders, Anas Abualia, Moses Akentuna, Louay N. Mohammad, Samuel B. Cooper, Samuel B. Cooper

Faculty Publications

When exposed to sun radiation and heat, asphalt binders age, resulting in reduced flexibility, cracking, and pavement failure. Given the increasing demands of traffic, environmental concerns, and resource scarcity, highway agencies and researchers are actively seeking solutions that meet performance requirements and demonstrate awareness of using non-renewable resources. Epoxy asphalt (EA) promotes sustainability concepts due to its production at significantly lower mixing and compaction temperatures, enhanced durability, improved serviceability, reduced maintenance needs, and successful recycling and reuse in hot asphalt mixtures. Crumb rubber, a widely recognized recycled waste tire material, is considered a viable option for promoting sustainability and enhancing …


A Review Of The Rheological Consistency Of Materials, Alan Gurt, Michael Khonsari Jul 2024

A Review Of The Rheological Consistency Of Materials, Alan Gurt, Michael Khonsari

Faculty Publications

Despite the ubiquity and prevalence of rheological consistency across a wide range of industries, there is no clear consensus on its meaning or on one particular technique for quantifying it. Instead, there exist various definitions of “consistency” that are each specific to a given context, and each industry has its own procedure for measuring it. This paper organizes the many subjects and terminologies associated with consistency, providing a comprehensive guide of fundamental mechanics, fundamental properties, modeling techniques, and standardized tests that describe consistency. This includes outlining the rheological models that describe the behavior of viscoelastic and non-Newtonian materials as well …


A Facile And Sustainable Integrated Fabrication Strategy For Multi-Performance 316l Stainless Steel, Yang Yang, Yi Zhu, Michael M. Khonsari, Sai Wang, Wei Song, Huayong Yang, Yu Zhang Jul 2024

A Facile And Sustainable Integrated Fabrication Strategy For Multi-Performance 316l Stainless Steel, Yang Yang, Yi Zhu, Michael M. Khonsari, Sai Wang, Wei Song, Huayong Yang, Yu Zhang

Faculty Publications

Additive manufacturing enables innovative design and integrated manufacturing of complex components. Metallic components with multi-performance and high reliability are always desirable for a broad range of high-end industries. Multi-material additive manufacturing is a promising way to provide multiple performances, yet there exist several persistent challenges on multi-material sustainability and recycling, interfacial defects and strength, dimensional accuracy and fineness, and manufacturing efficiency and cost, prohibiting its widespread practical applications. In this study, we introduce an additive/modification integrated manufacturing (AMIM) strategy for fabricating highly reliable multi-performance metals using only a single material with a one-step process. We demonstrate that, through a unique …


Deep Learning-Based Geomorphic Feature Identification In Dredge Pit Marine Environment, Wenqiang Zhang, Xiaobing Chen, Xiangwei Zhou, Jianhua Chen, Jianguo Yuan, Taibiao Zhao, Kehui Xu Jul 2024

Deep Learning-Based Geomorphic Feature Identification In Dredge Pit Marine Environment, Wenqiang Zhang, Xiaobing Chen, Xiangwei Zhou, Jianhua Chen, Jianguo Yuan, Taibiao Zhao, Kehui Xu

Faculty Publications

Deep learning methods paired with sidescan sonar (SSS) are commonly used in underwater search-and-rescue operations for drowning victims, wrecks, and airplanes. However, these techniques are primarily used to detect mine-like objects and are rarely applied to identifying features in dynamic dredge pit environments. In this study, we present a Sandy Point dredge pit (SPDP) dataset, in which high-resolution SSS data were collected from the west flank of the Mississippi bird-foot delta on the Louisiana inner shelf. This dataset contains a total of 385 SSS images. We then introduce a new Effective Geomorphology Classification model (EGC). Through ablation studies, we analyze …


A Step In A New Direction: Nvidia Gpu Kernel Driver Memory Forensics, Christopher J. Bowen, Andrew Case, Ibrahim Baggili, Golden G. Richard Jul 2024

A Step In A New Direction: Nvidia Gpu Kernel Driver Memory Forensics, Christopher J. Bowen, Andrew Case, Ibrahim Baggili, Golden G. Richard

Faculty Publications

In the ever-expanding landscape of computation, graphics processing units have become one of the most essential types of devices for personal and commercial needs. Nearly all modern computers have one or more dedicated GPUs due to advancements in artificial intelligence, high-performance computing, 3D graphics rendering, and the growing demand for enhanced gaming experiences. As the GPU industry continues to grow, forensic investigations will need to incorporate these devices, given that they have large amounts of VRAM, computing power, and are used to process highly sensitive data. Past research has also shown that malware can hide its payloads within these devices …


On Enhancing Memory Forensics With Fame: Framework For Advanced Monitoring And Execution, Taha Gharaibeh, Ibrahim Baggili, Anas Mahmoud Jul 2024

On Enhancing Memory Forensics With Fame: Framework For Advanced Monitoring And Execution, Taha Gharaibeh, Ibrahim Baggili, Anas Mahmoud

Faculty Publications

Memory Forensics (MF) is an essential aspect of digital investigations, but practitioners often face time-consuming challenges when using popular tools like the Volatility Framework (VF). VF, a widely-adopted Python-based memory forensics tool, presents difficulties for practitioners due to its slow performance. Thus, in this study, we evaluated methods to accelerate VF without modifying its code by testing four alternative Python Just In Time (JIT) interpreters - CPython, Pyston, PyPy, and Pyjion - using CPython as our baseline. Tests were conducted on 14 memory samples, totaling 173 GB, using a search-intensive VF plugin for Windows hosts. Employing our custom Framework for …


Mars: The First Line Of Defense For Iot Incident Response, Karley M. Waguespack, Kaitlyn J. Smith, Olame A. Muliri, Ramyapandian Vijayakanthan, Aisha Ali-Gombe Jul 2024

Mars: The First Line Of Defense For Iot Incident Response, Karley M. Waguespack, Kaitlyn J. Smith, Olame A. Muliri, Ramyapandian Vijayakanthan, Aisha Ali-Gombe

Faculty Publications

The proliferation of Internet of Things (IoT) devices across homes, businesses, and industrial landscapes has significantly increased our capability to gather data and automate tasks. Despite their ubiquity, these devices are notably resource-constrained and frequently lack robust security defenses, presenting a substantial risk of intrusion and cyber threats. To address these concerns, we propose a novel anomaly-based host intrusion detection system specifically designed for IoT devices, titled MARS (Memory Anomaly Recognition System). MARS is designed to function as a crucial component in the incident response framework, acting as an early detection system for potential security breaches within an organization's network …


Analyzing Thermal Maturity Effect On Shale Organic Matter Via Peakforce Quantitative Nanomechanical Mapping, Chioma Onwumelu, Oladoyin Kolawole, Stephan Nordeng, Olufemi Olorode Jul 2024

Analyzing Thermal Maturity Effect On Shale Organic Matter Via Peakforce Quantitative Nanomechanical Mapping, Chioma Onwumelu, Oladoyin Kolawole, Stephan Nordeng, Olufemi Olorode

Faculty Publications

Organic-rich shales have gained significant attention in recent years due to their pivotal role in unconventional hydrocarbon production. These shale rocks undergo thermal maturation processes that alter their mechanical properties, making their study essential for subsurface operations. However, characterizing the mechanical properties of organic-rich shale is often challenging due to its multiscale nature and complex composition. This work aims to bridge that knowledge gap to fully understand the nanomechanical properties of Shale organic matter at various thermal maturation stages. This study employs PeakForce Quantitative Nanomechanical Mapping (PF-QNM) using Atomic Force Microscopy (AFM) to investigate how changes at the immature, early …


Understanding Differential Reductions In Undernutrition Among Districts In Rwanda Through The Perspectives Of Mid-Level And Community Actors On Policy Commitment And Policy Coherence, Elyse Iruhiriye, Edward A. Frongillo Ph.D., Deanna K. Olney, Emmanuel Niyongira, Simeon Nanama, Christine E. Blake Ph.D., Rd, Eugene Rwibasira, Paul Mbonyi Jul 2024

Understanding Differential Reductions In Undernutrition Among Districts In Rwanda Through The Perspectives Of Mid-Level And Community Actors On Policy Commitment And Policy Coherence, Elyse Iruhiriye, Edward A. Frongillo Ph.D., Deanna K. Olney, Emmanuel Niyongira, Simeon Nanama, Christine E. Blake Ph.D., Rd, Eugene Rwibasira, Paul Mbonyi

Faculty Publications

Understanding the drivers of improvements in child undernutrition at only the national level can mask subnational differences. This paper aimed to understand the contributions of factors in the enabling environment to observed differences in stunting reduction between districts in Rwanda. In 2017, we conducted 58 semi-structured interviews with mid-level actors (n = 38) and frontline workers (n = 20) implementing Rwanda's multi-sectoral nutrition policy in five districts in which stunting decreased (reduced districts) and five where it increased or stagnated (non-reduced districts) based on Rwanda's 2010 and 2014/15 Demographic and Health Surveys. Mid-level actors are government officials and service providers …


Reading Colonial Transitions: Archival Evidence And The Archaeology Of Indigenous Action In Nineteenth-Century California, Lee M. Panich, Gustavo Flores, Michael Wilcox, Monica V. Arellano Jul 2024

Reading Colonial Transitions: Archival Evidence And The Archaeology Of Indigenous Action In Nineteenth-Century California, Lee M. Panich, Gustavo Flores, Michael Wilcox, Monica V. Arellano

Faculty Publications

Archaeologists in North America and elsewhere are increasingly examining long-term Indigenous presence across multiple colonial systems, despite lingering conceptual and methodological challenges. We examine this issue in California, where archaeologists and others have traditionally overlooked Native persistence in the years between the official closing of the region's Franciscan missions in the 1830s and the onset of US settler colonialism in the late 1840s. In particular, we advocate for the judicious use of the documentary record to ask new questions of Indigenous life during this short but critical period, when many Native Californians were freed from the missions and sought new …


Functional Multivariable Logistic Regression With An Application To Hiv Viral Suppression Prediction, Siyuan Guo, Jiajia Zhang Ph.D., Yichao Wu, Alexander C. Mclain Ph.D., James W. Hardin, Bankole Olatosi Ph.D., Xiaoming Li Ph.D. Jul 2024

Functional Multivariable Logistic Regression With An Application To Hiv Viral Suppression Prediction, Siyuan Guo, Jiajia Zhang Ph.D., Yichao Wu, Alexander C. Mclain Ph.D., James W. Hardin, Bankole Olatosi Ph.D., Xiaoming Li Ph.D.

Faculty Publications

Motivated by improving the prediction of the human immunodeficiency virus (HIV) suppression status using electronic health records (EHR) data, we propose a functional multivariable logistic regression model, which accounts for the longitudinal binary process and continuous process simultaneously. Specifically, the longitudinal measurements for either binary or continuous variables are modeled by functional principal components analysis, and their corresponding functional principal component scores are used to build a logistic regression model for prediction. The longitudinal binary data are linked to underlying Gaussian processes. The estimation is done using penalized spline for the longitudinal continuous and binary data. Group-lasso is used to …


Ductape: A Steady-State, Axisymmetric Ducted Fan Analysis Code Designed For Gradient-Based Optimization, Judd Mehr, Andrew Ning Jul 2024

Ductape: A Steady-State, Axisymmetric Ducted Fan Analysis Code Designed For Gradient-Based Optimization, Judd Mehr, Andrew Ning

Faculty Publications

Electric ducted fans have become an intriguing option for the propulsion systems of clean, quiet advanced air mobility technologies due to their potential benefits in both aerodynamic efficiency and reduced noise profiles compared to open rotor systems. Exploration of conceptual electric ducted fan design in the context of novel, and often complex, applications may be greatly aided by the use of optimization techniques. Specifically, gradient-based optimization lends itself to the exploration of large, complex, multi-disciplinary systems due to its inherent scalability. Despite ducted fans/propellers having been relatively well studied for the last century, modern, gradient-based, optimization-ready analysis tools for ducted …


Parker Solar Probe Observations Of Energetic Particles In The Flank Of A Coronal Mass Ejection Close To The Sun, Nathan A. Schwadron, Stuart D. Bale, J Bonnell, A Case, M Shen, E R. Christian, C M S Cohen, A J. Davis, M I. Desai, K Goetz, J Giacalone, M E. Hill, J C. Kasper, K Korreck, D Larson, R Livi, T Lim, R A. Leske, O Malandraki, D Malaspina, W H. Matthaeus, D J. Mccomas, R L. Mcnutt, R A. Mewaldt, D G. Mitchell Jul 2024

Parker Solar Probe Observations Of Energetic Particles In The Flank Of A Coronal Mass Ejection Close To The Sun, Nathan A. Schwadron, Stuart D. Bale, J Bonnell, A Case, M Shen, E R. Christian, C M S Cohen, A J. Davis, M I. Desai, K Goetz, J Giacalone, M E. Hill, J C. Kasper, K Korreck, D Larson, R Livi, T Lim, R A. Leske, O Malandraki, D Malaspina, W H. Matthaeus, D J. Mccomas, R L. Mcnutt, R A. Mewaldt, D G. Mitchell

Faculty Publications

We present an event observed by Parker Solar Probe (PSP) at ∼0.2 au on 2022 March 2 in which imaging and in situ measurements coincide. During this event, PSP passed through structures on the flank of a streamer blowout coronal mass ejection (CME) including an isolated flux tube in front of the CME, a turbulent sheath, and the CME itself. Imaging observations and in situ helicity and principal variance signatures consistently show the presence of flux ropes internal to the CME. In both the sheath and the CME interval, the distributions are more isotropic, the spectra are softer, and the …


An Ixpe-Led X-Ray Spectropolarimetric Campaign On The Soft State Of Cygnus X-1: X-Ray Polarimetric Evidence For Strong Gravitational Lensing, James F. Steiner, Edward Nathan, Kun Hu, Henric Krawczynski, Michal Dovčiak, Alexandra Veledina, Fabio Muleri, Jiri Svoboda, Kevin Alabarta, Maxime Parra, Yash Bhargava, Giorgio Matt, Juri Poutanen, Pierre-Olivier Petrucci, Allyn F. Tennant, M Cristina Baglio, Luca Baldini, Samuel Barnier, Sudip Bhattacharyya, Stefano Bianchi, Maimouna Brigitte, Mauricio Cabezas, Floriane Cangemi, Fiamma Capitanio, Jacob Casey, Nicole Rodriguez Cavero, Simone Castellano, Elisabetta Cavazzuti, Sohee Chun, Eugene Churazov, Enrico Costa, Niccolò Di Lalla, Alessandro Di Marco, Elise Egron, Elise Egron, Melissa Ewing, Sergio Fabiani, Javier A. García, David A. Green, Victoria Grinberg, Petr Hadrava, Adam Ingram, Philip Kaaret, Fabian Kislat, Takao Kitaguchi, Vadim Kravtsov, Brankica Kubátová, Fabio La Monaca, Luca Latronico, Vladislav Loktev, Christian Malacaria, Frédéric Marin, Andrea Marinucci, Olga Maryeva, Guglielmo Mastroserio, Tsunefumi Mizuno, Michela Negro, Nicola Omodei, Jakub Podgorný, John Rankin, Ajay Ratheesh, Lauren Rhodes, David M. Russell, Miroslav Šlechta, Paolo Soffitta, Sean Spooner, Valery Suleimanov, Francesco Tombesi, Sergei A. Trushkin, Martin C. Weisskopf, Silvia Zane, Andrzej A. Zdziarski, Sixuan Zhang, Wenda Zhang, Menglei Zhou, Iván Agudo, Lucio A. Antonelli, Matteo Bachetti, Wayne H. Baumgartner, Ronaldo Bellazzini, Stephen D. Bongiorno, Raffaella Bonino, Alessandro Brez, Niccolò Bucciantini, Chien-Ting Chen, Stefano Ciprini, Alessandra De Rosa, Ettore Del Monte, Laura Di Gesu, Immacolata Donnarumma, Victor Doroshenko, Steven R. Ehlert, Teruaki Enoto, Yuri Evangelista, Riccardo Ferrazzoli, Shuichi Gunji, Kiyoshi Hayashida, Jeremy Heyl, Wataru Iwakiri, Svetlana G. Jorstad, Vladimir Karas, Jeffery J. Kolodziejczak, Ioannis Liodakis, Simone Maldera, Alberto Manfreda, Alan P. Marscher, Herman L. Marshall, Francesco Massaro, Ikuyuki Mitsuishi, Chi-Yung Ng, Stephen L. O'Dell, Chiara Oppedisano, Alessandro Papitto, George G. Pavlov, Abel L. Peirson, Matteo Perri, Melissa Pesce-Rollins, Maura Pilia, Andrea Possenti, Simonetta Puccetti, Brian D. Ramsey, Oliver J. Roberts, Roger W. Romani, Carmelo Sgrò, Patrick Slane, Gloria Spandre, Douglas A. Swartz, Toru Tamagawa, Fabrizio Tavecchio, Roberto Taverna, Yuzuru Tawara, Nicholas E. Thomas, Alessio Trois, Sergey S. Tsygankov, Roberto Turolla, Jacco Vink, Kinwah Wu, Fei Xie Jul 2024

An Ixpe-Led X-Ray Spectropolarimetric Campaign On The Soft State Of Cygnus X-1: X-Ray Polarimetric Evidence For Strong Gravitational Lensing, James F. Steiner, Edward Nathan, Kun Hu, Henric Krawczynski, Michal Dovčiak, Alexandra Veledina, Fabio Muleri, Jiri Svoboda, Kevin Alabarta, Maxime Parra, Yash Bhargava, Giorgio Matt, Juri Poutanen, Pierre-Olivier Petrucci, Allyn F. Tennant, M Cristina Baglio, Luca Baldini, Samuel Barnier, Sudip Bhattacharyya, Stefano Bianchi, Maimouna Brigitte, Mauricio Cabezas, Floriane Cangemi, Fiamma Capitanio, Jacob Casey, Nicole Rodriguez Cavero, Simone Castellano, Elisabetta Cavazzuti, Sohee Chun, Eugene Churazov, Enrico Costa, Niccolò Di Lalla, Alessandro Di Marco, Elise Egron, Elise Egron, Melissa Ewing, Sergio Fabiani, Javier A. García, David A. Green, Victoria Grinberg, Petr Hadrava, Adam Ingram, Philip Kaaret, Fabian Kislat, Takao Kitaguchi, Vadim Kravtsov, Brankica Kubátová, Fabio La Monaca, Luca Latronico, Vladislav Loktev, Christian Malacaria, Frédéric Marin, Andrea Marinucci, Olga Maryeva, Guglielmo Mastroserio, Tsunefumi Mizuno, Michela Negro, Nicola Omodei, Jakub Podgorný, John Rankin, Ajay Ratheesh, Lauren Rhodes, David M. Russell, Miroslav Šlechta, Paolo Soffitta, Sean Spooner, Valery Suleimanov, Francesco Tombesi, Sergei A. Trushkin, Martin C. Weisskopf, Silvia Zane, Andrzej A. Zdziarski, Sixuan Zhang, Wenda Zhang, Menglei Zhou, Iván Agudo, Lucio A. Antonelli, Matteo Bachetti, Wayne H. Baumgartner, Ronaldo Bellazzini, Stephen D. Bongiorno, Raffaella Bonino, Alessandro Brez, Niccolò Bucciantini, Chien-Ting Chen, Stefano Ciprini, Alessandra De Rosa, Ettore Del Monte, Laura Di Gesu, Immacolata Donnarumma, Victor Doroshenko, Steven R. Ehlert, Teruaki Enoto, Yuri Evangelista, Riccardo Ferrazzoli, Shuichi Gunji, Kiyoshi Hayashida, Jeremy Heyl, Wataru Iwakiri, Svetlana G. Jorstad, Vladimir Karas, Jeffery J. Kolodziejczak, Ioannis Liodakis, Simone Maldera, Alberto Manfreda, Alan P. Marscher, Herman L. Marshall, Francesco Massaro, Ikuyuki Mitsuishi, Chi-Yung Ng, Stephen L. O'Dell, Chiara Oppedisano, Alessandro Papitto, George G. Pavlov, Abel L. Peirson, Matteo Perri, Melissa Pesce-Rollins, Maura Pilia, Andrea Possenti, Simonetta Puccetti, Brian D. Ramsey, Oliver J. Roberts, Roger W. Romani, Carmelo Sgrò, Patrick Slane, Gloria Spandre, Douglas A. Swartz, Toru Tamagawa, Fabrizio Tavecchio, Roberto Taverna, Yuzuru Tawara, Nicholas E. Thomas, Alessio Trois, Sergey S. Tsygankov, Roberto Turolla, Jacco Vink, Kinwah Wu, Fei Xie

Faculty Publications

We present the first X-ray spectropolarimetric results for Cygnus X-1 in its soft state from a campaign of five IXPE observations conducted during 2023 May–June. Companion multiwavelength data during the campaign are likewise shown. The 2–8 keV X-rays exhibit a net polarization degree PD = 1.99% ± 0.13% (68% confidence). The polarization signal is found to increase with energy across the Imaging X-ray Polarimetry Explorer’s (IXPE) 2–8 keV bandpass. The polarized X-rays exhibit an energy-independent polarization angle of PA = −25.°7 ± 1.°8 east of north (68% confidence). This is consistent with being aligned to Cyg X-1’s au-scale compact radio …


Interstellar Neutral Hydrogen In The Heliosphere: New Horizons Observations In The Context Of Models, P Swaczyna, M Bzowski, K Dialynas, L Dyke, F Fraternale, A Galli, J Heerikhuisen, M Z. Kornbleuth, D Koutroumpa, I Kowalska-Leszczyńska, M A. Kubiak, A T. Michael, H -R Müller, M Opher, Fatemeh Rahmanifard Jul 2024

Interstellar Neutral Hydrogen In The Heliosphere: New Horizons Observations In The Context Of Models, P Swaczyna, M Bzowski, K Dialynas, L Dyke, F Fraternale, A Galli, J Heerikhuisen, M Z. Kornbleuth, D Koutroumpa, I Kowalska-Leszczyńska, M A. Kubiak, A T. Michael, H -R Müller, M Opher, Fatemeh Rahmanifard

Faculty Publications

Interstellar neutral (ISN) hydrogen is the most abundant species in the outer heliosheath and the very local interstellar medium (VLISM). Charge-exchange collisions in the outer heliosheath result in filtration, reducing the ISN hydrogen density inside the heliosphere. Additionally, these atoms are intensively ionized close to the Sun, resulting in a substantial reduction of their density within a few astronomical units from the Sun. The products of this ionization—pickup ions (PUIs)—are detected by charged particle detectors. The Solar Wind Around Pluto instrument on New Horizons provides, for the first time, PUI observations from the distant heliosphere. We analyze the observations collected …


Parker Solar Probe Observations Of Energetic Particles In The Flank Of A Coronal Mass Ejection Close To The Sun, Nathan A. Schwadron, Stuart D. Bale, J Bonnell, A Case, M Shen, E R. Christian, C M S Cohen, A J. Davis, M I. Desai, K Goetz, J Giacalone, M E. Hill, J C. Kasper, K Korreck, D Larson, R Livi, T Lim, R A. Leske, O Malandraki, D Malaspina, W H. Matthaeus, D J. Mccomas, R L. Mcnutt, R A. Mewaldt, D G. Mitchell, Jonathan T. Niehof, M. Pulupa, Francesco Pecora, J. S. Rankin, Charles Smith, E. C. Stone, J. R. Szalay, A. Vourlidas, M. E. Wiedenbeck, P. Whittlesey Jul 2024

Parker Solar Probe Observations Of Energetic Particles In The Flank Of A Coronal Mass Ejection Close To The Sun, Nathan A. Schwadron, Stuart D. Bale, J Bonnell, A Case, M Shen, E R. Christian, C M S Cohen, A J. Davis, M I. Desai, K Goetz, J Giacalone, M E. Hill, J C. Kasper, K Korreck, D Larson, R Livi, T Lim, R A. Leske, O Malandraki, D Malaspina, W H. Matthaeus, D J. Mccomas, R L. Mcnutt, R A. Mewaldt, D G. Mitchell, Jonathan T. Niehof, M. Pulupa, Francesco Pecora, J. S. Rankin, Charles Smith, E. C. Stone, J. R. Szalay, A. Vourlidas, M. E. Wiedenbeck, P. Whittlesey

Faculty Publications

We present an event observed by Parker Solar Probe (PSP) at ∼0.2 au on 2022 March 2 in which imaging and in situ measurements coincide. During this event, PSP passed through structures on the flank of a streamer blowout coronal mass ejection (CME) including an isolated flux tube in front of the CME, a turbulent sheath, and the CME itself. Imaging observations and in situ helicity and principal variance signatures consistently show the presence of flux ropes internal to the CME. In both the sheath and the CME interval, the distributions are more isotropic, the spectra are softer, and the …


Persistent Behavior In Solar Energetic Particle Time Series, N V. Sarlis, G Livadiotis, D J. Mccomas, M E. Cuesta, L Y. Khoo, C M S Cohen, D G. Mitchell, Nathan A. Schwadron Jul 2024

Persistent Behavior In Solar Energetic Particle Time Series, N V. Sarlis, G Livadiotis, D J. Mccomas, M E. Cuesta, L Y. Khoo, C M S Cohen, D G. Mitchell, Nathan A. Schwadron

Faculty Publications

We investigate the long-term persistence of solar energetic particle (SEP) time series by means of four different methods: Hurst rescaled range R/S analysis, detrended fluctuation analysis, centered moving average analysis, and the fluctuation of natural time under the time reversal method. For these analyses, we use data sets from the Integrated Science Investigation of the Sun instrument suite on board NASA's Parker Solar Probe. Background systematic noise is modeled using cross-correlation analysis between different SEP energy channels and subtracted from the original data. The use of these four methods for deriving the time-series persistence allows us to (i) differentiate between …


Sediment Ballast Accelerates Sinking Of Alaska North Slope Crude Oil Measured Ex Situ With Surface Water From Cook Inlet, Jesse Ross, Nancy Kinner, Susan Saupe, Kai Ziervogel Jul 2024

Sediment Ballast Accelerates Sinking Of Alaska North Slope Crude Oil Measured Ex Situ With Surface Water From Cook Inlet, Jesse Ross, Nancy Kinner, Susan Saupe, Kai Ziervogel

Faculty Publications

Oil spilled into the ocean interacts with suspended matter forming aggregates that transport oil into subsurface layers and towards the bottom. We conducted a series of laboratory experiments to explore aggregation of oil with natural phytoplankton assemblages from Cook Inlet, Alaska at three times during a spring bloom. Oil and phytoplankton formed marine oil snow (MOS) that remained positively buoyant with a small fraction of MOS sinking to the bottom of our experimental bottles. Seawater treatments amended with suspended sediments formed oil-mineral aggregates (OMAs) with an oil capacity similar to MOS (∼20% of aggregate area was covered with oil). OMAs …


An Ixpe-Led X-Ray Spectropolarimetric Campaign On The Soft State Of Cygnus X-1: X-Ray Polarimetric Evidence For Strong Gravitational Lensing, James F. Steiner, Edward Nathan, Kun Hu, Henric Krawczynski, Michal Dovčiak, Alexandra Veledina, Fabio Muleri, Jiri Svoboda, Kevin Alabarta, Maxime Parra, Yash Bhargava, Giorgio Matt, Juri Poutanen, Pierre-Olivier Petrucci, Allyn F. Tennant, M Cristina Baglio, Luca Baldini, Samuel Barnier, Sudip Bhattacharyya, Stefano Bianchi, Maimouna Brigitte, Mauricio Cabezas, Floriane Cangemi, Fiamma Capitanio, Jacob Casey Jul 2024

An Ixpe-Led X-Ray Spectropolarimetric Campaign On The Soft State Of Cygnus X-1: X-Ray Polarimetric Evidence For Strong Gravitational Lensing, James F. Steiner, Edward Nathan, Kun Hu, Henric Krawczynski, Michal Dovčiak, Alexandra Veledina, Fabio Muleri, Jiri Svoboda, Kevin Alabarta, Maxime Parra, Yash Bhargava, Giorgio Matt, Juri Poutanen, Pierre-Olivier Petrucci, Allyn F. Tennant, M Cristina Baglio, Luca Baldini, Samuel Barnier, Sudip Bhattacharyya, Stefano Bianchi, Maimouna Brigitte, Mauricio Cabezas, Floriane Cangemi, Fiamma Capitanio, Jacob Casey

Faculty Publications

We present the first X-ray spectropolarimetric results for Cygnus X-1 in its soft state from a campaign of five IXPE observations conducted during 2023 May–June. Companion multiwavelength data during the campaign are likewise shown. The 2–8 keV X-rays exhibit a net polarization degree PD = 1.99% ± 0.13% (68% confidence). The polarization signal is found to increase with energy across the Imaging X-ray Polarimetry Explorer’s (IXPE) 2–8 keV bandpass. The polarized X-rays exhibit an energy-independent polarization angle of PA = −25.°7 ± 1.°8 east of north (68% confidence). This is consistent with being aligned to Cyg X-1’s au-scale compact radio …


Interstellar Neutral Hydrogen In The Heliosphere: New Horizons Observations In The Context Of Models, P Swaczyna, M Bzowski, K Dialynas, L Dyke, F Fraternale, A Galli, J Heerikhuisen, M Z. Kornbleuth, D Koutroumpa, I Kowalska-Leszczyńska, M A. Kubiak, A T. Michael, H -R Müller, M Opher, Fatemeh Rahmanifard Jul 2024

Interstellar Neutral Hydrogen In The Heliosphere: New Horizons Observations In The Context Of Models, P Swaczyna, M Bzowski, K Dialynas, L Dyke, F Fraternale, A Galli, J Heerikhuisen, M Z. Kornbleuth, D Koutroumpa, I Kowalska-Leszczyńska, M A. Kubiak, A T. Michael, H -R Müller, M Opher, Fatemeh Rahmanifard

Faculty Publications

Interstellar neutral (ISN) hydrogen is the most abundant species in the outer heliosheath and the very local interstellar medium (VLISM). Charge-exchange collisions in the outer heliosheath result in filtration, reducing the ISN hydrogen density inside the heliosphere. Additionally, these atoms are intensively ionized close to the Sun, resulting in a substantial reduction of their density within a few astronomical units from the Sun. The products of this ionization—pickup ions (PUIs)—are detected by charged particle detectors. The Solar Wind Around Pluto instrument on New Horizons provides, for the first time, PUI observations from the distant heliosphere. We analyze the observations collected …


Murder On The Hearsay Trail, Jeffrey Bellin Jul 2024

Murder On The Hearsay Trail, Jeffrey Bellin

Faculty Publications

Judges, lawyers, and law students struggle to apply American evidence law’s most distinctive feature—the hearsay prohibition. The problem is that hearsay is difficult to master and somewhat dull. At the same time, hearsay evidence is ubiquitous and important. Every litigator has a story about a judge’s eccentric hearsay rulings; mine is the trial judge who waved his hand dismissively at hearsay objections, letting witnesses answer on the grounds that “I want to hear it.” And the case law is littered with appellate opinions scolding trial judges for erroneous hearsay rulings while introducing errors of their own.

That is just the …


Legal Support For Local Election Officials, Rebecca Green Jul 2024

Legal Support For Local Election Officials, Rebecca Green

Faculty Publications

Local election officials (“LEOs”) face enormous pressure. They must administer elections when a wide swath of the American public has grown mistrustful of their work; they increasingly face ominous personal attacks and threats; they cope with chronic underfunding of elections; and they must navigate frequent changes in the law governing elections. Lawyers provide a critical avenue of support for local election officials. They provide guidance on how to implement legislative mandates and judicial orders; they anticipate and prevent disputes from arising; and they represent election officials when they or their offices are sued—a more common occurrence today than ever. Although …