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Articles 39601 - 39630 of 294560

Full-Text Articles in Physical Sciences and Mathematics

Two Warm Neptunes Transiting Hip 9618 Revealed By Tess And Cheops, H. P. Osborn, G. Nowak, G. Hébrard, T. Masseron, J. Lillo-Box, E. Pallé, A. Bekkelien, H.-G. Florén, P. Guterman, A. E. Simon, V. Adibekyan, A. Bieryla, L. Borsato, A. Brandeker, D. R. Ciardi, A. Collier Cameron, K. A. Collins, J. A. Egger, D. Gandolfi, M. J. Hooton, D. W. Latham, M. Lendl, E. C. Matthews, A. Tuson, S. Ulmer-Moll, A. Vanderburg, T. G. Wilson, C. Ziegler, Y. Alibert, R. Alonso, G. Anglada, L. Arnold, J. Asquier, D. Barrado Y Navascues, W. Baumjohann, T. Beck, A. A. Belinski, W. Benz, F. Biondi, I. Boisse, X. Bonfils, C. Broeg, L. A. Buchhave, T. Bárczy, S. C. C. Barros, J. Cabrera, C. Cardona Guillen, I. Carleo, A. Castro-González, S. Charnoz, J. Christiansen, P. Cortes-Zuleta, S. Csizmadia, S. Dalal, M. B. Davies, M. Deleuil, X. Delfosse, L. Delrez, B.-O. Demory, A. B. Dunlavey, D. Ehrenreich, A. Erikson, R. B. Fernandes, A. Fortier, T. Forveille, L. Fossati, M. Fridlund, M. Gillon, R. F. Goeke, M. V. Goliguzova, E. J. Gonzales, M. N. Günther, M. Güdel, N. Heidari, C. E. Henze, S. Howell, S. Hoyer, J. I. Frey, K. G. Isaak, J. M. Jenkins, F. Kiefer, L. Kiss, J. Korth, P. F. L. Maxted, J. Laskar, A. Lecavelier Des Etangs, C. Lovis, M. B. Lund, R. Luque, D. Magrin, J. M. Almenara, E. Martioli, M. Mecina, J. V. Medina, D. Moldovan, M. Morales-Calderón, G. Morello, C. Moutou, F. Murgas, Eric L.N. Jensen, V. Nascimbeni, G. Olofsson, R. Ottensamer, I. Pagano, G. Peter, G. Piotto, D. Pollacco, D. Queloz, R. Ragazzoni, N. Rando, H. Rauer, I. Ribas, G. Ricker, O. D. S. Demangeon, A. M. S. Smith, N. Santos, G. Scandariato, S. Seager, S. G. Sousa, M. Steller, G. M. Szabó, D. Ségransan, N. Thomas, S. Udry, B. Ulmer, V. Van Grootel, R. Vanderspek, N. Walton, J. N. Winn Aug 2023

Two Warm Neptunes Transiting Hip 9618 Revealed By Tess And Cheops, H. P. Osborn, G. Nowak, G. Hébrard, T. Masseron, J. Lillo-Box, E. Pallé, A. Bekkelien, H.-G. Florén, P. Guterman, A. E. Simon, V. Adibekyan, A. Bieryla, L. Borsato, A. Brandeker, D. R. Ciardi, A. Collier Cameron, K. A. Collins, J. A. Egger, D. Gandolfi, M. J. Hooton, D. W. Latham, M. Lendl, E. C. Matthews, A. Tuson, S. Ulmer-Moll, A. Vanderburg, T. G. Wilson, C. Ziegler, Y. Alibert, R. Alonso, G. Anglada, L. Arnold, J. Asquier, D. Barrado Y Navascues, W. Baumjohann, T. Beck, A. A. Belinski, W. Benz, F. Biondi, I. Boisse, X. Bonfils, C. Broeg, L. A. Buchhave, T. Bárczy, S. C. C. Barros, J. Cabrera, C. Cardona Guillen, I. Carleo, A. Castro-González, S. Charnoz, J. Christiansen, P. Cortes-Zuleta, S. Csizmadia, S. Dalal, M. B. Davies, M. Deleuil, X. Delfosse, L. Delrez, B.-O. Demory, A. B. Dunlavey, D. Ehrenreich, A. Erikson, R. B. Fernandes, A. Fortier, T. Forveille, L. Fossati, M. Fridlund, M. Gillon, R. F. Goeke, M. V. Goliguzova, E. J. Gonzales, M. N. Günther, M. Güdel, N. Heidari, C. E. Henze, S. Howell, S. Hoyer, J. I. Frey, K. G. Isaak, J. M. Jenkins, F. Kiefer, L. Kiss, J. Korth, P. F. L. Maxted, J. Laskar, A. Lecavelier Des Etangs, C. Lovis, M. B. Lund, R. Luque, D. Magrin, J. M. Almenara, E. Martioli, M. Mecina, J. V. Medina, D. Moldovan, M. Morales-Calderón, G. Morello, C. Moutou, F. Murgas, Eric L.N. Jensen, V. Nascimbeni, G. Olofsson, R. Ottensamer, I. Pagano, G. Peter, G. Piotto, D. Pollacco, D. Queloz, R. Ragazzoni, N. Rando, H. Rauer, I. Ribas, G. Ricker, O. D. S. Demangeon, A. M. S. Smith, N. Santos, G. Scandariato, S. Seager, S. G. Sousa, M. Steller, G. M. Szabó, D. Ségransan, N. Thomas, S. Udry, B. Ulmer, V. Van Grootel, R. Vanderspek, N. Walton, J. N. Winn

Physics & Astronomy Faculty Works

HIP 9618 (HD 12572, TOI-1471, TIC 306263608) is a bright (G = 9.0 mag) solar analogue. TESS photometry revealed the star to have two candidate planets with radii of 3.9 ± 0.044 R⊕ (HIP 9618 b) and 3.343 ± 0.039 R⊕ (HIP 9618 c). While the 20.77291 d period of HIP 9618 b was measured unambiguously, HIP 9618 c showed only two transits separated by a 680-d gap in the time series, leaving many possibilities for the period. To solve this issue, CHEOPS performed targeted photometry of period aliases to attempt to recover the true period of planet c, …


On The Chemistry Of Aqueous Ammonium Acetate Droplets During Native Electrospray Ionization Mass Spectrometry, Lars Konermann, Zeyuan Liu, Yousef Haidar, Methew J. Willians, Nicholas A. Bainbridge Aug 2023

On The Chemistry Of Aqueous Ammonium Acetate Droplets During Native Electrospray Ionization Mass Spectrometry, Lars Konermann, Zeyuan Liu, Yousef Haidar, Methew J. Willians, Nicholas A. Bainbridge

Chemistry Publications

Ammonium acetate (NH4Ac) is a widely used solvent additive in native electrospray ionization (ESI) mass spectrometry. NH4Ac can undergo proton transfer to form ammonia and acetic acid (NH4+ + Ac- → NH3 + HAc). The volatility of these products ensures that electrosprayed ions are free of undesired adducts. NH4Ac dissolution in water yields pH 7, providing “physiological” conditions. However, NH4Ac is not a buffer at pH 7 because NH4+ and Ac- are not a conjugate acid/base pair (L. Konermann, J. Am. Soc. Mass Spectrom. 2017 …


Site-Specific Glyco-Engineering Of Recombinant Thrombomodulin, Joseph M. Keil Aug 2023

Site-Specific Glyco-Engineering Of Recombinant Thrombomodulin, Joseph M. Keil

ETD Archive

Thrombomodulin (TM), a membrane glycoprotein predominately expressed on endothelium, plays essential roles in regulating local hemostatic balance. Particularly, TM modulates the activity of thrombin from a procoagulant to an anticoagulant protease. When bound to TM, thrombin activates plasma protein C, which selectively inactivates coagulation factors Va and VIIIa. At the same time, TM-bound thrombin is unable to cleave fibrinogen or to activate platelets diminishing its procoagulant activity. recombinant TM456 is a promising anticoagulant candidate, but it has a very short half-life. TM is a proteoglycan and its O-linked glycosaminoglycan (GAG), chondroitin sulfate (CS), on the D3 domain contributes to TM’s …


Verification Of Astm Centrifugation Equations For Soil Suction Determination, Esteban Maclein Miranda Pinzon Aug 2023

Verification Of Astm Centrifugation Equations For Soil Suction Determination, Esteban Maclein Miranda Pinzon

Graduate Theses and Dissertations

The unit correction constant (B) in the ASTM D6836 standard needs to be evaluated. The B-value was proposed to be 0.00548 instead of 0.00553. This apparent discrepancy led to an investigation comparing the predicted and measured suction values for high air entry (HAE) ceramic disks. A Beckman-Coulter Model J6-MI six-bay centrifuge and a WP4C Dewpoint Potentiameter were used in the testing program. HAE ceramic disks rated with bubbling pressures of 3-bar and 5-bar were used as analogue soil specimens. The HAE ceramic disks were spun in the small-scale centrifuge to apply prescribed suction amounts and then placed in the WP4C …


Estimation Of Gross Primary Productivity Of Rice In Arkansas Using The Vegetation Photosynthesis Model, Riasad Bin Mahbub Aug 2023

Estimation Of Gross Primary Productivity Of Rice In Arkansas Using The Vegetation Photosynthesis Model, Riasad Bin Mahbub

Graduate Theses and Dissertations

An estimate of the gross primary productivity (GPP) of rice fields can be instrumental to understand their harvest yield and to fulfill an array of agricultural monitoring needs. One of the most common satellite-based models to estimate GPP is the vegetation photosynthesis model (VPM). In this study, we use the VPM model for rice cropland in Arkansas and validate our findings against 16 site-years in-situ data (eddy covariance (EC)). At the site scale, results validated against 16 site-years have shown that the VPM with site information (R2 = 0.71, MAE = 2.90 g C m-2day- 1, and RMSE = 4.04 …


Raised Field Agriculture On The North Coast Of Peru: Environmental Investigations In The Casma Valley, Seth Price Aug 2023

Raised Field Agriculture On The North Coast Of Peru: Environmental Investigations In The Casma Valley, Seth Price

Graduate Theses and Dissertations

The Casma Valley, located on the central-northern coast of Peru, is home to a system of raised agricultural fields unique to the region. Relicts of pre-Hispanic culture, these fields are unusually well-preserved and primarily unaffected by modern agriculture. Multiscalar investigations of the Casma Valley raised fields revealed distinct anthropogenic soil alteration and landscape modification patterns. This dissertation assesses why Late Chimú (1300-1470 CE) societies in the Casma Valley converted ca. 2 km2 of land into raised agricultural field systems. This project is designed to investigate the composition and operation of raised fields, the short and long-term effects of field operation, …


Analyzing The Adoption, Cropping Rotation, And Impact Of Winter Cover Crops In The Mississippi Alluvial Plain (Map) Region Through Remote Sensing Technologies, Zobaer Ahmed Aug 2023

Analyzing The Adoption, Cropping Rotation, And Impact Of Winter Cover Crops In The Mississippi Alluvial Plain (Map) Region Through Remote Sensing Technologies, Zobaer Ahmed

Graduate Theses and Dissertations

This dissertation explores the application of remote sensing technologies in conservation agriculture, specifically focusing on identifying and mapping winter cover crops and assessing voluntary cover crop adoption and cropping patterns in the Arkansas portion of the Mississippi Alluvial Plain (MAP). In the first chapter, a systematic review using the PRISMA methodology examines the last 30 years of thematic research, development, and trends in remote sensing applied to conservation agriculture from a global perspective. The review uncovers a growing interest in remote sensing-based research in conservation agriculture and emphasizes the necessity for further studies dedicated to conservation practices. Among the 68 …


If Everything Is A Matter Of Degree, Why Do Crisp Techniques Often Work Better?, Miroslav Svitek, Olga Kosheleva, Vladik Kreinovich Aug 2023

If Everything Is A Matter Of Degree, Why Do Crisp Techniques Often Work Better?, Miroslav Svitek, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

Numerous examples from different application domain confirm the statement of Lotfi Zadeh -- that everything is a matter of degree. Because of this, one would expect that in most -- if not all -- practical situations taking these degrees into account would lead to more effective control, more effective prediction, etc. In practice, while in many cases, this indeed happens, in many other cases, "crisp" methods -- methods that do not take these degrees into account -- work better. In this paper, we provide two possible explanations for this discrepancy: an objective one -- explaining that the optimal (best-fit) model …


Improving The Design And Conduct Of Aquatic Toxicity Studies With Oils Based On 20 Years Of Croserf Experience, Wa Stubblefield, M Barron, G Bragin, Me Delorenzo, B De Jourdan, B Echols, Dp French-Mccay, P Jackman, Jr Loughery, Tf Parkerton, D. Abigail Renegar, Jl Rodriguez-Gil Aug 2023

Improving The Design And Conduct Of Aquatic Toxicity Studies With Oils Based On 20 Years Of Croserf Experience, Wa Stubblefield, M Barron, G Bragin, Me Delorenzo, B De Jourdan, B Echols, Dp French-Mccay, P Jackman, Jr Loughery, Tf Parkerton, D. Abigail Renegar, Jl Rodriguez-Gil

Marine & Environmental Sciences Faculty Articles

Laboratory toxicity testing is a key tool used in oil spill science, spill effects assessment, and mitigation strategy decisions to minimize environmental impacts. A major consideration in oil toxicity testing is how to replicate real-world spill conditions, oil types, weathering states, receptor organisms, and modifying environmental factors under laboratory conditions. Oils and petroleum-derived products are comprised of thousands of compounds with different physicochemical and toxicological properties, and this leads to challenges in conducting and interpreting oil toxicity studies. Experimental methods used to mix oils with aqueous test media have been shown to influence the aqueous-phase hydrocarbon composition and concentrations, hydrocarbon …


Magnetic-Field-Driven Director Configuration Transitions In Radial Nematic Liquid Crystal Droplets, S. Ettinger, C. G. Slaughter, S. H. Parra, J. M. Kikkawa, Peter J. Collings, A. G. Yodh Aug 2023

Magnetic-Field-Driven Director Configuration Transitions In Radial Nematic Liquid Crystal Droplets, S. Ettinger, C. G. Slaughter, S. H. Parra, J. M. Kikkawa, Peter J. Collings, A. G. Yodh

Physics & Astronomy Faculty Works

We study the director configurations of nematic liquid crystal (NLC) droplets with homeotropic anchoring in a magnetic field and report observation of a magnetic-field-driven transition from a deformed radial to an axial-with-defect configuration. Magnetic-field-induced transitions in NLC droplets differ fundamentally from the traditional planar Freedericksz transition due to the spherical droplet geometry and resulting topological defect. This transition has been studied theoretically, but the director configurations and mechanism of defect evolution in an applied magnetic field have yet to be observed experimentally. To this end, we combine polarized optical microscopy with a variable electromagnet (≤ 1 T) for continuous observation …


Resource Provisioning For Data-Intensive User-Facing Applications, Huiyang Li Aug 2023

Resource Provisioning For Data-Intensive User-Facing Applications, Huiyang Li

Computer Science and Engineering Dissertations - Archive

Data-intensive, User-facing Services (DUSes) such as web searching, digital marketing, online social networking, and online retailing are critical workloads in clouds and datacenters. Meeting stringent query tail-latency Service Level Objectives (SLO) for DUS queries is essential for optimal user experience and business success. However, achieving these objectives is challenging due to the scale-out nature of DUese workloads and the varying resource demands of queries with different fanouts. Additionally, the design and configuration options for clusters significantly impact query performance. In this dissertation, we present solutions of DUSes performance online and offline optimization. We highlight the importance of reducing query tail …


Deep Learning For Molecular Property Prediction, Hehuan Ma Aug 2023

Deep Learning For Molecular Property Prediction, Hehuan Ma

Computer Science and Engineering Dissertations - Archive

Drug discovery has always been a crucial task for society, and molecular property prediction is one of the fundamental problem. It is responsible for identifying the target properties or severe side-effects, so that certain molecules can be selected as the candidates of drugs. Traditional methods usually conduct a series of biochemical experiments to test the molecular properties, which may take up to decades. Nowadays, this process can be facilitated due to the rapid growth of deep learning methods. I present my work toward solving this critical problem by utilizing deep learning techniques. My research study can be summarized in three …


A Novel Regularized Orthonormalized Partial Least Squares Model For Multi-View Learning, Ce Bian Aug 2023

A Novel Regularized Orthonormalized Partial Least Squares Model For Multi-View Learning, Ce Bian

Mathematics Dissertations - Archive

Over the past few years, the size of data dimensions or features has been increasing in various fields of science and engineering, owing to the rapid pace of data collection and the development of more advanced storage methods. However, to handle high-dimensional data, dimensionality reduction is essential before performing classification or regression tasks to eliminate noisy features. There are several numerical methods available for reducing data dimensionality, such as Canonical Correlation Analysis (CCA), Principal Component Analysis (PCA), and Linear Discriminant Analysis (LDA). While these methods offer valuable approaches to data dimensionality reduction, they do come with certain limitations. CCA, for …


Simulating Strongly Coupled Many-Body Systems With Quantum Algorithms, Manqoba Qedindaba Hlatshwayo Aug 2023

Simulating Strongly Coupled Many-Body Systems With Quantum Algorithms, Manqoba Qedindaba Hlatshwayo

Dissertations

The complexity of the nuclear many-body problem is a severe obstacle to finding a general and accurate numerical approach needed to simulate medium-mass and heavy nuclei. Even with the advent of exascale classical computing, the impediment of exponential growth of the Hilbert space renders the problem intractable for most classical calculations. In the last few years, quantum algorithms have become an attractive alternative for practitioners because quantum computers are more efficient in simulating quantum physics than classical computers. While a fully fault-tolerant universal quantum computer will not be realized soon, this dissertation explores quantum algorithms for simulating nuclear physics suitable …


Compact Representatives Of Databases And Responsible Data Management, Suraj Shetiya Aug 2023

Compact Representatives Of Databases And Responsible Data Management, Suraj Shetiya

Computer Science and Engineering Dissertations - Archive

With the advent of advanced computational models, we are being constantly judged by AI systems, complex algorithmic systems based on data that has been collected about us. These analysis are critical as they span many wide spread areas of our lives. For instance, these systems have been shown to find effective ways to fight back and make informed decisions during the COVID-19 pandemic. The wide spread use of these models naturally give rise to a few questions regarding explaining decisions that these systems have made, fairness questions in various parts of these systems. In this dissertation, we present three important …


Long Non-Coding Rnas In Inflammation, Macrophage Activation, And Inflammatory Human Diseases, Avisankar Chini Aug 2023

Long Non-Coding Rnas In Inflammation, Macrophage Activation, And Inflammatory Human Diseases, Avisankar Chini

Chemistry & Biochemistry Dissertations - Archive

Inflammation and immune signaling is central to infection and diseases. Growing evidence suggests that along with protein coding genes, long non-coding RNAs (lncRNAs) play a critical role in disease onset, combat, and recovery against pathogen, damaged and self-altered cells. Our lab has been extensively studying the role of lncRNA HOTAIR (HOX transcript antisense intergenic RNA) in gene regulation and epigenetics, and eventually discovered its hidden function regulating inflammation and immune signaling in macrophage, a major type of cell involved in immunity. Previous scholars in our lab have successfully demonstrated lncRNA HOTAIR’s regulatory molecular mechanism elucidating its specific role in cellular …


Reactive Atmosphere Pyrolysis(Rap) Of Silicon Carbo Nitride (Sicn), Akshada Bharat Hande Aug 2023

Reactive Atmosphere Pyrolysis(Rap) Of Silicon Carbo Nitride (Sicn), Akshada Bharat Hande

Chemistry & Biochemistry Theses - Archive

Polymer Derived Ceramics (PDCs) are synthesized by converting liquid polymer precursors into ceramics through controlled pyrolysis. This study focuses on silicon carbonitride (SiCN) ceramics obtained from Ceraset Polysilazane (Durazane1800) precursor. The influence of pyrolysis atmospheres, including inert (Ar, N2) and reactive (H2) environments, on the thermal conversion of Durazane1800 into SiCN ceramics is investigated. The resulting ceramics' chemical variations are explored through phase analysis using X-ray diffraction (XRD), Raman spectroscopy, and thermogravimetric analysis (TGA). Notably, the impact of hydrogen versus nitrogen atmospheres on the conversion process is analyzed, shedding light on their distinct contributions to the composition and properties of …


Experimental And Theoretical Studies Of Fluid-Solid Coupling Processes Of Tight Rock Media, Tao Zhang Aug 2023

Experimental And Theoretical Studies Of Fluid-Solid Coupling Processes Of Tight Rock Media, Tao Zhang

Earth & Environmental Sciences Dissertations - Archive

This study covers the application of continuum mechanics in the realm of rock work in geological studies. Continuum mechanics encompasses two major branches: fluid mechanics that deals with fluid behavior, and solid mechanics pertaining to the behavior of rock media. The research focuses on comprehending the mechanical behavior of rocks as a continuous mass, offering a comprehensive perspective for analyzing geological structures, fluid flow, and rock mechanics. Under the framework of continuum mechanics applied to rock media, following the sequence of the rock/solid properties, fluid flow properties, and the fluid-solid coupling behavior, this dissertation is divided into four sections, each …


Fuzz Testing Of Zigbee Protocol Implementations, Mengfei Ren Aug 2023

Fuzz Testing Of Zigbee Protocol Implementations, Mengfei Ren

Computer Science and Engineering Dissertations - Archive

ABSTRACT: In recent years, we have witnessed the increasing of the Internet of Things (IoT) devices deployed by many areas, such as home automation, healthcare, manufacture, and smart vehicle. Among the numerous IoT wireless standards available, Zigbee stands out as one of the most globally popular choices, with major companies like Amazon, Samsung, IKEA, Huawei, and Xiaomi incorporating it into their products. Notably, Zigbee has even been utilized in NASA's Mars mission, where it serves as the communication radio between the flying drone and the Perseverance rover. However, with the rapid growth of Zigbee's global market presence, the incentive for …


A Machine Learning Approach To Constructing Ramsey Graphs Leads To The Trahtenbrot-Zykov Problem., Emily Hawboldt Aug 2023

A Machine Learning Approach To Constructing Ramsey Graphs Leads To The Trahtenbrot-Zykov Problem., Emily Hawboldt

Electronic Theses and Dissertations

Attempts at approaching the well-known and difficult problem of constructing Ramsey graphs via machine learning lead to another difficult problem posed by Zykov in 1963 (now commonly referred to as the Trahtenbrot-Zykov problem): For which graphs F does there exist some graph G such that the neighborhood of every vertex in G induces a subgraph isomorphic to F? Chapter 1 provides a brief introduction to graph theory. Chapter 2 introduces Ramsey theory for graphs. Chapter 3 details a reinforcement learning implementation for Ramsey graph construction. The implementation is based on board game software, specifically the AlphaZero program and its …


Evaluating Chatgpt For Recommendation: How Does The Ability To Converse Impact Recommendation?, Kyle Spurlock Aug 2023

Evaluating Chatgpt For Recommendation: How Does The Ability To Converse Impact Recommendation?, Kyle Spurlock

Electronic Theses and Dissertations

Recommendation algorithms have become an absolute necessity in the modern world to avoid information overload. However, the interaction between the human and the system is largely superficial and without any real contact. If you are given poor recommendations, you have no choice but to sift through mountains of content on your own until the model learns to accommodate your tastes more. This is bad for business as well as the consumer. Recently, large language models like ChatGPT have seen a significant rise in popularity due to their ease of use and wide range of knowledge. It has now become nearly …


Constrained Route Optimization With Fleet Considerations For Electrified Heavy-Duty Freight Vehicles, Zarin Subah Shamma Aug 2023

Constrained Route Optimization With Fleet Considerations For Electrified Heavy-Duty Freight Vehicles, Zarin Subah Shamma

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Almost 75% of traffic-related emissions are caused by heavy-duty freight trucks and significantly impact neighborhoods, schools, and communities around shipping and distribution lines. With poor air quality and respiratory health, many children in at-risk and disadvantaged communities experience high rates of asthma, lower attendance in school, and lower concentration. This research creates to improve the impacts of heavy-duty electric freight by improving the route efficiency (in terms of energy, time, or route distance) of EV trucks. Our software and algorithms are tested in a simulation environment using data from several thousand fleet trucks operating in the Salt Lake City area. …


Influence Of Hydrologic History On Nitrogen Cycling In Lake Sediments, Emily Jainarain Aug 2023

Influence Of Hydrologic History On Nitrogen Cycling In Lake Sediments, Emily Jainarain

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water quality is declining in freshwater lakes around the world due to environmental change and anthropogenic activities that threaten the physical, ecological, and geochemical integrity of freshwater ecosystems. Excess N and P in lakes can cause eutrophication, a major driver of water quality impairment that leads to excessive algal growth, or harmful algal blooms (HABs), and poses risks to recreation, fisheries, and public drinking water. Water level fluctuations in lakes are expected to become more frequent and intense as climate change increases periods of drought and alters precipitation patterns, and fluctuations may stimulate biogeochemical reactions in littoral sediments that add …


Comparing Commonly Used Aquatic Habitat Modeling Methods For Native Fishes, Eryn K. Turney Aug 2023

Comparing Commonly Used Aquatic Habitat Modeling Methods For Native Fishes, Eryn K. Turney

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water resources are managed for a variety of human needs, including agriculture, industrial and municipal consumption, hydropower generation, and recreation. There has been a recent push to incorporate habitat needs of aquatic wildlife into water management models alongside these other uses, particularly as competition for limited water resources in a changing climate has reduced instream flow and contributed to declining native fish populations. Habitat models are used to estimate species distributions and differentiate between suitable and unsuitable habitat based on variables important to a given species, but are not usually incorporated into water management models. Because there are many ways …


Effects Of Soil Amendments On Water Quality And Hydrologic Properties In Low Impact Development Systems, Lily Wetterlin Aug 2023

Effects Of Soil Amendments On Water Quality And Hydrologic Properties In Low Impact Development Systems, Lily Wetterlin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Low impact development (LID) systems are practices that use natural elements, such as soils and vegetation, to absorb and filter stormwater to protect water quality and aquatic habitats. Many LID designs use native soils; however, urban soils typically have a limited potential for infiltrating and treating stormwater. Incorporation of soil amendments, such as compost and biochar, into LID soils can improve the physical properties of soil. However, soil amendments may increase or decrease pollutants in the water leaving the site. A comparison of the effects of different types and application rates of amendments on water quality is necessary to determine …


Deuterium Escape On Photoevaporating Sub-Neptunes, Pin-Gao Gu, Howard Chen Aug 2023

Deuterium Escape On Photoevaporating Sub-Neptunes, Pin-Gao Gu, Howard Chen

Aerospace, Physics, and Space Science Faculty Publications

We investigate the evolution of the deuterium-to-hydrogen (D/H) mass ratio driven by EUV photoevaporation of hydrogen-rich atmospheres of close-in sub-Neptunes around solar-type stars. For the first time, the diffusion-limited approach in conjunction with energy-limited photoevaporation is considered in evaluating deuterium escape from evolving exoplanet H/He envelopes. We find that the planets with smaller initial gas envelopes and thus smaller sizes can lead to weaker atmospheric escape, which facilitates hydrogen–deuterium fractionation. Specifically, in our grid of simulations with a low envelope mass fraction of less than 0.005, a low-mass sub-Neptune (4–5 M⊕) at about 0.25–0.4 au or a high-mass sub-Neptune …


Statistical Inference On Lung Cancer Screening Using The National Lung Screening Trial Data., Farhin Rahman Aug 2023

Statistical Inference On Lung Cancer Screening Using The National Lung Screening Trial Data., Farhin Rahman

Electronic Theses and Dissertations

This dissertation consists of three research projects on cancer screening probability modeling. In these projects, the three key modeling parameters (sensitivity, sojourn time, transition density) for cancer screening were estimated, along with the long-term outcomes (including overdiagnosis as one outcome), the optimal screening time/age, the lead time distribution, and the probability of overdiagnosis at the future screening time were simulated to provide a statistical perspective on the effectiveness of cancer screening programs. In the first part of this dissertation, a statistical inference was conducted for male and female smokers using the National Lung Screening Trial (NLST) chest X-ray data. A …


Urban Vulnerability Analysis Based On Micro-Geographic Unit With Multi-Source Data—Case Study In Urumqi, Xinjiang, China, Jianghua Zheng, Danlin Yu, Chuqiao Han, Zhe Wang Aug 2023

Urban Vulnerability Analysis Based On Micro-Geographic Unit With Multi-Source Data—Case Study In Urumqi, Xinjiang, China, Jianghua Zheng, Danlin Yu, Chuqiao Han, Zhe Wang

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

This study introduces a novel approach to urban public safety analysis inspired by a streetscape analysis commonly applied in urban criminology, leveraging the concept of micro-geographical units to account for urban spatial heterogeneity. Recognizing the intrinsic uniformity within these smaller, distinct environments of a city, the methodology represents a shift from large-scale regional studies to a more localized and precise exploration of urban vulnerability. The research objectives focus on three key aspects: first, establishing a framework for identifying and dividing cities into micro-geographical units; second, determining the type and nature of data that effectively illustrate the potential vulnerability of these …


Iowa Waste Reduction Center Newsletter, August 2023, University Of Northern Iowa. Iowa Waste Reduction Center. Aug 2023

Iowa Waste Reduction Center Newsletter, August 2023, University Of Northern Iowa. Iowa Waste Reduction Center.

Iowa Waste Reduction Center Newsletter

Contents:

--- STAR4D at the Iowa State Fair
--- Farewell to Our Interns
--- Reminder: Iowa Recycling and Solid Waste Management Conference
--- Free Energy Assessments
--- Industry News


Causal Inference And Machine Learning Methods In Parkinson's Disease Data Analysis, Albert Pierce Aug 2023

Causal Inference And Machine Learning Methods In Parkinson's Disease Data Analysis, Albert Pierce

Computational and Data Sciences (PhD) Dissertations

This dissertation documents an investigation into Parkinson’s Disease utilizing machine learning and causal inference methods. I will cover a descriptive analysis of Parkinson’s Disease (PD) in a vast, high-quality database and present costs associated with Parkinson’s Disease medications. I also researched a causal inference method assessing the Carbidopa-Levodopa effect on two-year survival and a causal survival analysis on a one-to-five-year survival comparing no drug use and Carbidopa-Levodopa in Parkinson’s Disease patients.

For my classification with Parkinson’s gait, patients were monitored with a smartphone and an additional 6 Inertial Measurement Unit (IMU) sensors to collect clinical gait measures. I used classical …