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Full-Text Articles in Physical Sciences and Mathematics

2024 February 1 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University Feb 2024

2024 February 1 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

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Watershed, Lake, And Food Web Factors Influence Diazotrophic Cyanobacteria In Mountain Lakes, Lara Jansen, Daniel Sobota, Yangdong Pan, Angela Strecker Feb 2024

Watershed, Lake, And Food Web Factors Influence Diazotrophic Cyanobacteria In Mountain Lakes, Lara Jansen, Daniel Sobota, Yangdong Pan, Angela Strecker

Environmental Science and Management Faculty Publications and Presentations

Cyanobacterial blooms can occur in freshwater ecosystems largely isolated from development and not experiencing extensive cultural eutrophication. For example, remote mountain lakes can experience intense blooms of diazotrophic (nitrogen-fixing) cyanobacteria caused by factors acting at different spatial and temporal scales. In this study, we examined how cross-scale interactions among watershed, lake, and food web characteristics influence diazotrophic cyanobacteria biovolume in mountain lakes. We quantified diazotrophic cyanobacteria biovolume, zooplankton abundance, and physico-chemical variables for 29 lakes in the Cascade Mountains of Oregon, USA, in summer 2019. Watershed characteristics were compiled from historical datasets available for the region. Diazotrophic cyanobacteria biovolume ranged …

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Jwst-Tsthigh Contrast: Asymmetries, Dust Populations, And Hints Of A Collision In The Β Pictoris Disk With Nircam And Miri, Isabel Rebollido, Christopher C. Stark, Jens Kammerer, Marshall D. Perrin, Kellen Lawson, Laurent Pueyo, Christine Chen, Dean Hines, Julien H. Girard, Kadin Worthen, Carl Ingerbretsen, Sarah Betti, Mark Clampin, David Golimowski, Kielan Hoch, Nikole K. Lewis, Cicero X. Lu, Roeland P. Van Der Marel, Emily Rickman, Sara Seager, Rémi Soummer, Jeff A. Valenti, Kimberly Ward-Duong, C. Matt Mountain Feb 2024

Jwst-Tsthigh Contrast: Asymmetries, Dust Populations, And Hints Of A Collision In The Β Pictoris Disk With Nircam And Miri, Isabel Rebollido, Christopher C. Stark, Jens Kammerer, Marshall D. Perrin, Kellen Lawson, Laurent Pueyo, Christine Chen, Dean Hines, Julien H. Girard, Kadin Worthen, Carl Ingerbretsen, Sarah Betti, Mark Clampin, David Golimowski, Kielan Hoch, Nikole K. Lewis, Cicero X. Lu, Roeland P. Van Der Marel, Emily Rickman, Sara Seager, Rémi Soummer, Jeff A. Valenti, Kimberly Ward-Duong, C. Matt Mountain

Astronomy: Faculty Publications

We present the first JWST Mid-Infrared Instrument (MIRI) and Near Infrared Camera (NIRCam) observations of the prominent debris disk around β Pictoris. Coronagraphic observations in eight filters spanning from 1.8 to 23 μm provide an unprecedentedly clear view of the disk at these wavelengths. The objectives of the observing program were to investigate the dust composition and distribution and to investigate the presence of planets in the system. In this paper, we focus on the disk components, providing surface brightness measurements for all images and a detailed investigation of the asymmetries observed. A companion paper by Kammerer et al. will …

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Vlti/Gravity Provides Evidence The Young, Substellar Companion Hd 136164 Ab Formed Like A “Failed Star”, William O. Balmer, L. Pueyo, S. Lacour, J. J. Wang, T. Stolker, J. Kammerer, N. Pourré, M. Nowak, E. Rickman, S. Blunt, A. Sivaramakrishnan, D. Sing, K. Wagner, G. D. Marleau, A. M. Lagrange, R. Abuter, A. Amorim, R. Asensio-Torres, J. P. Berger, H. Beust, A. Boccaletti, A. Bohn, M. Bonnefoy, H. Bonnet, M. S. Bordoni, G. Bourdarot, W. Brandner, F. Cantalloube, P. Caselli, B. Charnay, Et Al, Kimberly Ward-Duong Feb 2024

Vlti/Gravity Provides Evidence The Young, Substellar Companion Hd 136164 Ab Formed Like A “Failed Star”, William O. Balmer, L. Pueyo, S. Lacour, J. J. Wang, T. Stolker, J. Kammerer, N. Pourré, M. Nowak, E. Rickman, S. Blunt, A. Sivaramakrishnan, D. Sing, K. Wagner, G. D. Marleau, A. M. Lagrange, R. Abuter, A. Amorim, R. Asensio-Torres, J. P. Berger, H. Beust, A. Boccaletti, A. Bohn, M. Bonnefoy, H. Bonnet, M. S. Bordoni, G. Bourdarot, W. Brandner, F. Cantalloube, P. Caselli, B. Charnay, Et Al, Kimberly Ward-Duong

Astronomy: Faculty Publications

Young, low-mass brown dwarfs orbiting early-type stars, with low mass ratios (q ≲ 0.01), appear to be intrinsically rare and present a formation dilemma: could a handful of these objects be the highest-mass outcomes of “planetary” formation channels (bottom up within a protoplanetary disk), or are they more representative of the lowest-mass “failed binaries” (formed via disk fragmentation or core fragmentation)? Additionally, their orbits can yield model-independent dynamical masses, and when paired with wide wavelength coverage and accurate system age estimates, can constrain evolutionary models in a regime where the models have a wide dispersion depending on the initial conditions. …

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Geotechnical Characterisation Of Coal Spoil Piles Using High-Resolution Optical And Multispectral Data: A Machine Learning Approach, Sureka Thiruchittampalam, Bikram Pratap Banerjee, Nancy F. Glenn, Simit Raval Feb 2024

Geotechnical Characterisation Of Coal Spoil Piles Using High-Resolution Optical And Multispectral Data: A Machine Learning Approach, Sureka Thiruchittampalam, Bikram Pratap Banerjee, Nancy F. Glenn, Simit Raval

Geosciences Faculty Publications and Presentations

Geotechnical characterisation of spoil piles has traditionally relied on the expertise of field specialists, which can be both hazardous and time-consuming. Although unmanned aerial vehicles (UAV) show promise as a remote sensing tool in various applications; accurately segmenting and classifying very high-resolution remote sensing images of heterogeneous terrains, such as mining spoil piles with irregular morphologies, presents significant challenges. The proposed method adopts a robust approach that combines morphology-based segmentation, as well as spectral, textural, structural, and statistical feature extraction techniques to overcome the difficulties associated with spoil pile characterisation. Additionally, it incorporates minimum redundancy maximum relevance (mRMR) based feature …

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Geothermal Play Fairway Analysis, Part 2: Gis Methodology, Jacob Deangelo, John W. Shervais, Jonathan M. Glen, Dennis Nielson, Sabodh Garg, Patrick F. Dobson, Erika Gasperikova, Eric Sonnenthal, Lee M. Liberty, Drew L. Siler, James P. Evans Feb 2024

Geothermal Play Fairway Analysis, Part 2: Gis Methodology, Jacob Deangelo, John W. Shervais, Jonathan M. Glen, Dennis Nielson, Sabodh Garg, Patrick F. Dobson, Erika Gasperikova, Eric Sonnenthal, Lee M. Liberty, Drew L. Siler, James P. Evans

Geosciences Faculty Publications and Presentations

Play Fairway Analysis (PFA) in geothermal exploration originates from a systematic methodology developed within the petroleum industry and is based on a geologic, geophysical, and hydrologic framework of identified geothermal systems. We tailored this methodology to study the geothermal resource potential of the Snake River Plain and surrounding region, but it can be adapted to other geothermal resource settings. We adapted the PFA approach to geothermal resource exploration by cataloging the critical elements controlling exploitable hydrothermal systems, establishing risk matrices that evaluate these elements in terms of both probability of success and level of knowledge, and building a code-based ‘processing …

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The Portable Hand Streamer: Rapid Seismic Imaging For Shallow Targets, Lee M. Liberty, L. Thomas Otheim Feb 2024

The Portable Hand Streamer: Rapid Seismic Imaging For Shallow Targets, Lee M. Liberty, L. Thomas Otheim

Geosciences Faculty Publications and Presentations

In this paper, we introduce a portable hand streamer seismic system. The system is appropriate for characterizing the mechanical properties of geologic and engineered materials in the upper 5 to 10 m depth and for reflection imaging from tens to hundreds of meters depth. Unlike other seismic land streamer systems that are typically pulled behind a vehicle with a long string of geophones, our recording system and electric seismic source are contained within an electric utility cart to allow ease of mobility for a single operator. Our 48-channel contact-coupled streamer is tethered to the cart to enable low-effort data collection. …

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Brief Communication: Recent Estimates Of Glacier Mass Loss For Western North America From Laser Altimetry, Brian Menounos, Caitlyn Forentine, Alex A. Gardner, Andrew G. Fountain Feb 2024

Brief Communication: Recent Estimates Of Glacier Mass Loss For Western North America From Laser Altimetry, Brian Menounos, Caitlyn Forentine, Alex A. Gardner, Andrew G. Fountain

Geology Faculty Publications and Presentations

Glaciers in western North American outside of Alaska are often overlooked in global studies because their potential to contribute to changes in sea level is small. Nonetheless, these glaciers represent important sources of freshwater, especially during times of drought. Differencing recent ICESat-2 data from a digital elevation model derived from a combination of synthetic aperture radar data (TerraSAR-X/TanDEM-X), we find that over the period 2013–2020, glaciers in western North America lost mass at a rate of 12:3+3:5 Gt yr-1. This rate is comparable to the rate of mass loss (11:71:0 Gt yr1) for the period 2018– 2022 calculated …

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2024 February - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University Feb 2024

2024 February - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

No abstract provided.

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Zircon And The Role Of Magmatic Petrogenesis In The Formation Of Felsic-Hosted Volcanogenic Massive Sulfide (Vms) Deposits: A Case Study From The Mid-Paleozoic Yukon-Tanana Terrane, Northern Canadian Cordillera, Matthew J. Manor, Stephen J. Piercey, Corey J. Wall Feb 2024

Zircon And The Role Of Magmatic Petrogenesis In The Formation Of Felsic-Hosted Volcanogenic Massive Sulfide (Vms) Deposits: A Case Study From The Mid-Paleozoic Yukon-Tanana Terrane, Northern Canadian Cordillera, Matthew J. Manor, Stephen J. Piercey, Corey J. Wall

Geosciences Faculty Publications and Presentations

Magmatism is a critical component in sustaining hydrothermal convection and metal transport during the formation of volcanogenic massive sulfide (VMS) deposits. Previous studies of magmatic petrogenesis in VMS systems have demonstrated that ore-related volcanic rocks have distinct whole-rock geochemical and isotopic signatures (i.e., high HFSE, REE, Th, εHf-Nd, zircon saturation T) relative to barren volcanic rocks, which supports models of elevated crustal heat flow during periods of ore deposition; however, the petrologic characteristics and intrinsic parameters (e.g., T, fO2) related to these magmatic events in VMS districts remain poorly understood. Arc–back-arc assemblages from the mid-Paleozoic Yukon-Tanana terrane …

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Chronostratigraphy Of Miocene Strata In The Berkeley Hills (California Coast Ranges, Usa) And The Arrival Of The San Andreas Transform Boundary, Stacey H. Gerasimov, Eben B. Hodgin, James L. Crowley, Nicholas L. Swanson-Hysell Feb 2024

Chronostratigraphy Of Miocene Strata In The Berkeley Hills (California Coast Ranges, Usa) And The Arrival Of The San Andreas Transform Boundary, Stacey H. Gerasimov, Eben B. Hodgin, James L. Crowley, Nicholas L. Swanson-Hysell

Geosciences Faculty Publications and Presentations

Miocene strata of the Claremont, Orinda, and Moraga formations of the Berkeley Hills (California Coast Ranges, USA) record sedimentation and volcanism during the passage of the Mendocino triple junction and early evolution of the San Andreas fault system. Detrital zircon laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) age spectra indicate a change in sedimentary provenance between the marine Claremont formation (Monterey Group) and the terrestrial Orinda and Moraga Formations associated with uplift of Franciscan Complex lithologies. A sandstone from the Claremont formation produced a detrital zircon chemical abrasion–isotope dilution–thermal ionization mass spectrometry (CA-ID-TIMS) maximum depositional age of 13.298 ± 0.046 Ma, …

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From Norms Taker To Norms Breaker: A Comparative Study Of Turkey’S Nuclear Discourses Before And After The Ostensible Coup Of 2016, Sarah Tzinieris, Zenobia S. Homan, Cem Boke, Amna Javed Feb 2024

From Norms Taker To Norms Breaker: A Comparative Study Of Turkey’S Nuclear Discourses Before And After The Ostensible Coup Of 2016, Sarah Tzinieris, Zenobia S. Homan, Cem Boke, Amna Javed

International Journal of Nuclear Security

This article offers an analysis of public statements made by Turkish government leaders, contrasting official attitudes on nuclear nonproliferation before and after the alleged military coup attempt in 2016. Significant developments in this period include deteriorating democracy and the rule of law in Turkey and the emergence of destabilizing foreign policy differences between Turkey and Western states. President Recep Tayyip Erdoğan also sought to consolidate domestic power and play a more assertive security role in the Middle East. This analysis of official statements reveals a distinct shift in Turkey’s nonproliferation rhetoric after the 2016 coup. In particular, Turkish government ministers …

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Geothermal Play Fairway Analysis, Part 1: Example From The Snake River Plain, Idaho, John W. Shervais, Jacob Deangelo, Jonathan M. Glen, Dennis L. Nielson, Sabodh Garg, Patrick Dobson, Erika Gasperikova, Eric Sonnenthal, Lee M. Liberty, Dennis L. Newell, Drew Siler, James P. Evans Feb 2024

Geothermal Play Fairway Analysis, Part 1: Example From The Snake River Plain, Idaho, John W. Shervais, Jacob Deangelo, Jonathan M. Glen, Dennis L. Nielson, Sabodh Garg, Patrick Dobson, Erika Gasperikova, Eric Sonnenthal, Lee M. Liberty, Dennis L. Newell, Drew Siler, James P. Evans

Geosciences Faculty Publications and Presentations

The Snake River Plain (SRP) volcanic province overlies the track of the Yellowstone hotspot, a thermal anomaly that extends deep into the mantle. Most of the area is underlain by a basaltic volcanic province that overlies a mid-crustal intrusive complex, which in turn provides the long-term heat flux needed to sustain geothermal systems. Previous studies have identified several known geothermal resource areas within the SRP. For the geothermal study presented herein, our goals were to: (1) adapt the methodology of Play Fairway Analysis (PFA) for geothermal exploration to create a formal basis for its application to geothermal systems, (2) assemble …

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Efficient Unsupervised Video Hashing With Contextual Modeling And Structural Controlling, Jingru Duan, Yanbin Hao, Bin Zhu, Lechao Cheng, Pengyuan Zhou, Xiang Wang Feb 2024

Efficient Unsupervised Video Hashing With Contextual Modeling And Structural Controlling, Jingru Duan, Yanbin Hao, Bin Zhu, Lechao Cheng, Pengyuan Zhou, Xiang Wang

Research Collection School Of Computing and Information Systems

The most important effect of the video hashing technique is to support fast retrieval, which is benefiting from the high efficiency of binary calculation. Current video hash approaches are thus mainly targeted at learning compact binary codes to represent video content accurately. However, they may overlook the generation efficiency for hash codes, i.e., designing lightweight neural networks. This paper proposes an method, which is not only for computing compact hash codes but also for designing a lightweight deep model. Specifically, we present an MLP-based model, where the video tensor is split into several groups and multiple axial contexts are explored …

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Frameworks For Measuring Population Health: A Scoping Review, Sze Ling Chan, Clement Zhong Hao Ho, Nang Ei Ei Khaing, Ezra Ho, Candelyn Pong, Jia Sheng Guan, Calida Chua, Zongbin Li, Trudi Lim Wenqi, Sean Shao Wei Lam, Lian Leng Low, Choon How How Feb 2024

Frameworks For Measuring Population Health: A Scoping Review, Sze Ling Chan, Clement Zhong Hao Ho, Nang Ei Ei Khaing, Ezra Ho, Candelyn Pong, Jia Sheng Guan, Calida Chua, Zongbin Li, Trudi Lim Wenqi, Sean Shao Wei Lam, Lian Leng Low, Choon How How

Research Collection School Of Computing and Information Systems

Introduction Many regions in the world are using the population health approach and require a means to measure the health of their population of interest. Population health frameworks provide a theoretical grounding for conceptualization of population health and therefore a logical basis for selection of indicators. The aim of this scoping review was to provide an overview and summary of the characteristics of existing population health frameworks that have been used to conceptualize the measurement of population health. Methods We used the Population, Concept and Context (PCC) framework to define eligibility criteria of frameworks. We were interested in frameworks applicable …

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Detecting Outdated Code Element References In Software Repository Documentation, Wen Siang Tan, Markus Wagner, Christoph Treude Feb 2024

Detecting Outdated Code Element References In Software Repository Documentation, Wen Siang Tan, Markus Wagner, Christoph Treude

Research Collection School Of Computing and Information Systems

Outdated documentation is a pervasive problem in software development, preventing effective use of software, and misleading users and developers alike. We posit that one possible reason why documentation becomes out of sync so easily is that developers are unaware of when their source code modifications render the documentation obsolete. Ensuring that the documentation is always in sync with the source code takes considerable effort, especially for large codebases. To address this situation, we propose an approach that can automatically detect code element references that survive in the documentation after all source code instances have been deleted. In this work, we …

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Examining Sustainable Overseas Investment Information-Sharing Model For Automobile Enterprises: A Multi-Modal Weight Network Approach, Yuan Cheng, Xiaofang Chen, Changbo Lin, Sheqing Ma, Jie Feng Feb 2024

Examining Sustainable Overseas Investment Information-Sharing Model For Automobile Enterprises: A Multi-Modal Weight Network Approach, Yuan Cheng, Xiaofang Chen, Changbo Lin, Sheqing Ma, Jie Feng

Research Collection School Of Accountancy

In an era of globalization, automotive companies are increasingly looking to make overseas investments to expand their production capacity and explore foreign markets. However, the outcomes of such investments are often influenced by a myriad of factors, including policy changes, social dynamics, and market conditions. To address the need for a comprehensive overseas investment information-sharing model, this research proposes an innovative approach based on a multi-modal weight network. This model aims to provide users with a global perspective on overseas investment opportunities, encompassing policy insights, and market dynamics. It integrates data from various sources, offering multi-dimensional information on investment regions, …

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Generative Artificial Intelligence Consensus In A Trustless Network, Edward Kim, Samu Isozaki, Naomi Sirkin, Michael Robson Feb 2024

Generative Artificial Intelligence Consensus In A Trustless Network, Edward Kim, Samu Isozaki, Naomi Sirkin, Michael Robson

Computer Science: Faculty Publications

We performed a billion locality sensitive hash comparisons between artificially generated data samples to answer the critical question - can we reproduce the results of generative AI models? Reproducibility is one of the pillars of scientific research for verifiability, bench- marking, trust, and transparency. Futhermore, we take this research to the next level by verifying the “correctness” of generative AI output in a non-deterministic, trustless, decentralized network. We generate millions of data samples from a variety of open source diffusion and large language models and describe the procedures and trade-offs between generating more verses less deterministic output. Additionally, we analyze …

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Integral Representations Over Finite Limits For Quantum Amplitudes, Jack C. Straton Feb 2024

Integral Representations Over Finite Limits For Quantum Amplitudes, Jack C. Straton

Physics Faculty Publications and Presentations

We extend previous research to derive three additional M-1-dimensional integral representations over the interval [0,1]" The prior version covered the interval [0,∞]" role="presentation position: relative;">[0,∞][0,∞]. This extension applies to products of M Slater orbitals, since they (and wave functions derived from them) appear in quantum transition amplitudes. It enables the magnitudes of coordinate vector differences (square roots of polynomials) |x1−x2|=x12−2x1x2cosθ+x22" to be shifted from disjoint products of functions into a single quadratic form, allowing for the completion of its square. The M-1-dimensional integral representations of M Slater orbitals that both this extension and the prior version introduce …

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An Itpa Enzyme With Improved Substrate Selectivity, Nicholas E. Burgis, Kandise Vanwormer, Devin Robbins, Jonathan Smith Feb 2024

An Itpa Enzyme With Improved Substrate Selectivity, Nicholas E. Burgis, Kandise Vanwormer, Devin Robbins, Jonathan Smith

Chemistry and Biochemistry Faculty Publications

Recent clinical data have identified infant patients with lethal ITPA deficiencies. ITPA is known to modulate ITP concentrations in cells and has a critical function in neural development which is not understood. Polymorphism of the ITPA gene affects outcomes for both ribavirin and thiopurine based therapies and nearly one third of the human population is thought to harbor ITPA polymorphism. In a previous site-directed mutagenesis alanine screen of the ITPA substrate selectivity pocket, we identified the ITPA mutant, E22A, as a gain-of function mutant with enhanced ITP hydrolysis activity. Here we report a rational enzyme engineering experiment to investigate the …

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Amperometric Bio-Sensing Of Lactate And Oxygen Concurrently With Local Field Potentials During Status Epilepticus, Eliana Fernandes, Ana Ledo, Greg A. Gerhardt, Rui M. Barbosa Feb 2024

Amperometric Bio-Sensing Of Lactate And Oxygen Concurrently With Local Field Potentials During Status Epilepticus, Eliana Fernandes, Ana Ledo, Greg A. Gerhardt, Rui M. Barbosa

Neurology Faculty Publications

Epilepsy is a prevalent neurological disorder with a complex pathogenesis and unpredictable nature, presenting limited treatment options in >30 % of affected individuals. Neurometabolic abnormalities have been observed in epilepsy patients, suggesting a disruption in the coupling between neural activity and energy metabolism in the brain. In this study, we employed amperometric biosensors based on a modified carbon fiber microelectrode platform to directly and continuously measure lactate and oxygen dynamics in the brain extracellular space. These biosensors demonstrated high sensitivity, selectivity, and rapid response time, enabling in vivo measurements with high temporal and spatial resolution. In vivo recordings in the …

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An Efficiently Excited Eu3+ Luminescent Site Formed In Eu,O-Codoped Gan, Takenori Iwaya, Shuhei Ichikawa, Volkmar Dierolf, Brandon Mitchell, Hayley Austin, Dolf Timmerman, Jun Tatebayashi, Yasufumi Fujiwara Feb 2024

An Efficiently Excited Eu3+ Luminescent Site Formed In Eu,O-Codoped Gan, Takenori Iwaya, Shuhei Ichikawa, Volkmar Dierolf, Brandon Mitchell, Hayley Austin, Dolf Timmerman, Jun Tatebayashi, Yasufumi Fujiwara

Physics & Engineering Faculty Publications

For the development of III-nitride-semiconductor-based monolithic micro-light-emitting diode (LED) displays, Eu,O-codoped GaN (GaN:Eu,O) is a promising material candidate for the red LEDs. The luminescence efficiency of Eu-related emission strongly depends on the local atomic structure of Eu ions. Our previous research has revealed that post-growth thermal annealing is an effective method for reconfiguring luminescent sites, leading to a significant increase in light output. We observed the preferential formation of a site with a peak at similar to 2.004 eV by the annealing process. In this study, we demonstrate that it is a previously unidentified independent site (OMVPE-X) using combined excitation-emission …

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A Causal Inference Approach For Spike Train Interactions, Zach Saccomano Feb 2024

A Causal Inference Approach For Spike Train Interactions, Zach Saccomano

Dissertations, Theses, and Capstone Projects

Since the 1960s, neuroscientists have worked on the problem of estimating synaptic properties, such as connectivity and strength, from simultaneously recorded spike trains. Recent years have seen renewed interest in the problem coinciding with rapid advances in experimental technologies, including an approximate exponential increase in the number of neurons that can be recorded in parallel and perturbation techniques such as optogenetics that can be used to calibrate and validate causal hypotheses about functional connectivity. This thesis presents a mathematical examination of synaptic inference from two perspectives: (1) using in vivo data and biophysical models, we ask in what cases the …

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Self-Optimizing Feature Generation Via Categorical Hashing Representation And Hierarchical Reinforcement Crossing, Wangyang Ying, Dongjie Wang, Kunpeng Liu, Leilei Sun, Yanjie Fu Feb 2024

Self-Optimizing Feature Generation Via Categorical Hashing Representation And Hierarchical Reinforcement Crossing, Wangyang Ying, Dongjie Wang, Kunpeng Liu, Leilei Sun, Yanjie Fu

Computer Science Faculty Publications and Presentations

Feature generation aims to generate new and meaningful features to create a discriminative representation space. A generated feature is meaningful when the generated feature is from a feature pair with inherent feature interaction. In the real world, experienced data scientists can identify potentially useful feature-feature interactions, and generate meaningful dimensions from an exponentially large search space in an optimal crossing form over an optimal generation path. But, machines have limited human-like abilities. We generalize such learning tasks as self-optimizing feature generation. Self-optimizing feature generation imposes several under-addressed challenges on existing systems: meaningful, robust, and efficient generation. To tackle these challenges, …

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Experimental Characterization Of A Fully Polarimetric Pulsed Terahertz Spectroscopy System, Nikita Gurjar, Morgan E. Ware, Magda El-Shenawee Feb 2024

Experimental Characterization Of A Fully Polarimetric Pulsed Terahertz Spectroscopy System, Nikita Gurjar, Morgan E. Ware, Magda El-Shenawee

Electrical Engineering and Computer Science Faculty Publications and Presentations

A terahertz time domain pulsed spectroscopy system is modified to provide fully polarimetric radiation and analysis. The operation of this polarimetry system is characterized using a birefringent, x-cut quartz crystal. The modification is based on rotating the photoconductive antennas such that both the emitted and detected polarizations are out of the plane of incidence. Subsequently, broadband wire grid polarizers are used to select the incident and detected direction of linear polarization to be either parallel with (vertical) or perpendicular to (horizontal) the plane of incidence with the sample surface. The experiments are conducted in both transmission and reflection. Depending on …

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Sparse Bayesian Variable Selection In High‐Dimensional Logistic Regression Models With Correlated Priors, Zhuanzhuan Ma, Zifei Han, Souparno Ghosh, Liucang Wu, Min Wang Feb 2024

Sparse Bayesian Variable Selection In High‐Dimensional Logistic Regression Models With Correlated Priors, Zhuanzhuan Ma, Zifei Han, Souparno Ghosh, Liucang Wu, Min Wang

School of Mathematical & Statistical Sciences Faculty Publications

In this paper, we propose a sparse Bayesian procedure with global and local(GL) shrinkage priors for the problems of variable selection and classification in high-dimensional logistic regression models. In particular, we consider two types of GL shrinkage priors for the regression coefficients, the horseshoe (HS)prior and the normal-gamma (NG) prior, and then specify a correlated prior for the binary vector to distinguish models with the same size. The GL priors are then combined with mixture representations of logistic distribution to construct a hierarchical Bayes model that allows efficient implementation of a Markov chain Monte Carlo (MCMC) to generate samples from …

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A Finite Element Model For Hydro-Thermal Convective Flow In A Porous Medium: Effects Of Hydraulic Resistivity And Thermal Diffusivity, S. M. Mallikarjunaiah, Dambaru Bhatta Feb 2024

A Finite Element Model For Hydro-Thermal Convective Flow In A Porous Medium: Effects Of Hydraulic Resistivity And Thermal Diffusivity, S. M. Mallikarjunaiah, Dambaru Bhatta

School of Mathematical & Statistical Sciences Faculty Publications

In this article, a finite element model is implemented to analyze hydro-thermal convective flow in a porous medium. The mathematical model encompasses Darcy’s law for incompressible fluid behavior, which is coupled with a convection-diffusion-type energy equation to characterize the temperature in the porous medium. The current investigation presents an efficient, stable, and accurate finite element discretization for the hydro-thermal convective flow model. The well-posedness of the proposed discrete Galerkin finite element formulation is guaranteed due to the decoupling property and the linearity of the numerical method. Computational experiments confirm the optimal convergence rates for a manufactured solution. Several numerical results …

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Conditional Optimal Sets And The Quantization Coefficients For Some Uniform Distributions, Evans Nyanney, Megha Pandey, Mrinal Kanti Roychowdhury Feb 2024

Conditional Optimal Sets And The Quantization Coefficients For Some Uniform Distributions, Evans Nyanney, Megha Pandey, Mrinal Kanti Roychowdhury

School of Mathematical & Statistical Sciences Faculty Publications

Bucklew and Wise (1982) showed that the quantization dimension of an absolutely continuous probability measure on a given Euclidean space is constant and equals the Euclidean dimension of the space, and the quantization coefficient exists as a finite positive number. By giving different examples, in this paper, we have shown that the quantization coefficients for absolutely continuous probability measures defined on the same Euclidean space can be different. We have taken uniform distribution as a prototype of an absolutely continuous probability measure. In addition, we have also calculated the conditional optimal sets of n-points and the nth conditional quantization errors …

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Experimental Sars-Cov-2 Infection Of Elk And Mule Deer, Stephanie M. Porter, Airn E. Hartwig, Helle Bielefeldt-Ohmann, Jeffrey M. Marano, J. Jeffrey Root, Angela M. Bosco-Lauth Feb 2024

Experimental Sars-Cov-2 Infection Of Elk And Mule Deer, Stephanie M. Porter, Airn E. Hartwig, Helle Bielefeldt-Ohmann, Jeffrey M. Marano, J. Jeffrey Root, Angela M. Bosco-Lauth

United States Department of Agriculture Wildlife Services: Staff Publications

To assess the susceptibility of elk (Cervus canadensis) and mule deer (Odocoileus hemionus) to SARS-CoV-2, we performed experimental infections in both species. Elk did not shed infectious virus but mounted low-level serologic responses. Mule deer shed and transmitted virus and mounted pronounced serologic responses and thus could play a role in SARS-CoV-2 epidemiology.

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X-Ray Detection Of The Most Extreme Star-Forming Galaxies At The Cosmic Noon Via Strong Lensing, Q. Daniel Wang, Carlos Garcia Diaz, Patrick S. Kamieneski, Kevin C. Harrington, Min S. Yun, Nicholas Foo, Brenda L. Frye, Eric F. Jimenez-Andrade, Daizhong Liu, James D. Lowenthal, Belén Alcalde Pampliega, Massimo Pascale, Amit Vishwas, Mark A. Gurwell Feb 2024

X-Ray Detection Of The Most Extreme Star-Forming Galaxies At The Cosmic Noon Via Strong Lensing, Q. Daniel Wang, Carlos Garcia Diaz, Patrick S. Kamieneski, Kevin C. Harrington, Min S. Yun, Nicholas Foo, Brenda L. Frye, Eric F. Jimenez-Andrade, Daizhong Liu, James D. Lowenthal, Belén Alcalde Pampliega, Massimo Pascale, Amit Vishwas, Mark A. Gurwell

Astronomy: Faculty Publications

Hyperluminous infrared galaxies (HyLIRGs)ãre the most extreme star-forming systems observed in the early Universe,ãnd their properties still elude comprehensive understanding. We have undertakenã large XMM -Newton observing programme to probe the totalãccreting black hole population in three HyLIRGsãt z = 2.12, 3.25,ãnd 3.55, gravitationally lensed by foreground galaxies. Selected from the Planck All-Sky Survey to Analyse Gravitationally lensed Extreme Starbursts (PASSAGES), these HyLIRGs haveãpparent infrared luminosities > 10 14 L⊙. Our observãtions re vealed X-ray emission in each of them. PJ1336 + 49ãppears to be dominated by high-mass X-ray binaries (HMXBs). Remarkably, the luminosity of this non-AGN X-ray emission exceeds byã …

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