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Articles 57211 - 57240 of 302499

Full-Text Articles in Physical Sciences and Mathematics

Simulation Of Pituitary Organogenesis In Two Dimensions, Chace E. Covington Jul 2021

Simulation Of Pituitary Organogenesis In Two Dimensions, Chace E. Covington

Theses and Dissertations

The pituitary gland is a vital part of the endocrine system found in all vertebrates and is responsible for the production of hormones that influence many physiological processes in the organism’s body. Although much has been learned of pituitary organogenesis, studying the dynamics of the cells in the developing pituitary gland is difficult. Pituitary organogenesis has been studied through “snapshots” of a developing pituitary gland by removing and viewing the pituitary glands of different specimens. Thus, how the individual cells in the developing pituitary gland behave and interact with one another is not fully understood. To aid in understanding pituitary …


Alkyne Cyclization Involving A Zwitterionic Hexaruthenium Carbido Carbonyl Complex And The Synthesis Of The First-Nitrido Heterometallic Carbonyl Cluster Complexes, Nutan Damodhar Wakdikar Jul 2021

Alkyne Cyclization Involving A Zwitterionic Hexaruthenium Carbido Carbonyl Complex And The Synthesis Of The First-Nitrido Heterometallic Carbonyl Cluster Complexes, Nutan Damodhar Wakdikar

Theses and Dissertations

Chapter 1 introduces two related topics with the primary focus on the background of zwitterions and the conceptual understanding of a metal-complexed zwitterion. It also discusses the potential of a metal-complexed zwitterion for a carbon-carbon bond formation reaction. Synthesis of the metal carbonyl cluster, Ru6(µ6-C)(µ-CO)(CO)16, is also discussed in detail. Then, the background with the importance of heterometallic cluster complexes is discussed with the help of various examples used for catalysis.

The reaction of hexaruthenium carbido carbonyl cluster, Ru6(µ6-C)(µ-CO)(CO)16, with C2H2 and Me3NO yielding first examples of two new zwitterionic complexes, Ru6C(CO)15(μ−η2−C2H2NMe3), 2.2, and Ru6C(CO)14(μ3−η4−C4H4NMe3), 2.3, are presented in Chapter …


Carbon Storage Via Mineral Bonding In Subsoils A Review Of Soil Processes, Kiele Goins Jul 2021

Carbon Storage Via Mineral Bonding In Subsoils A Review Of Soil Processes, Kiele Goins

Theses and Dissertations

Soil is an important but often poorly understood portion of the carbon cycle. Soil can store more carbon than twice today’s atmosphere, but the factors that control carbon storage are often unclear. Carbon enters the soil through input of organic matter, erosion, and aerosol deposition and is lost mostly via microbial decomposition. Carbon loss in soil is impacted by the chemical composition of organic compounds, environmental factors, and human activities. Furthermore, as climate changes soil, carbon storage may be vulnerable. Although carbon can be stored throughout soil, carbon storage varies with depth. In topsoil, carbon is stored for short periods …


Characterization Of A High Affinity Glutathione Transporter And Its Impact On Glutathione Depleted Saccharomyces Cerevisiae, Tirthankar Bandyopadhyay Jul 2021

Characterization Of A High Affinity Glutathione Transporter And Its Impact On Glutathione Depleted Saccharomyces Cerevisiae, Tirthankar Bandyopadhyay

Theses and Dissertations

Thiol-disulfide redox homeostasis is integral for maintaining the redox status of proteins and other thiol-containing molecules within the cell. Among the many antioxidants and detoxifying enzymes and small peptides, glutathione (GSH) has proven to be critical for the preservation of function and structural integrity of the cell due to its functionality in areas like oxidative protein folding, thiol redox control, reactive oxygen species (ROS) and xenobiotics removal as well as iron regulation and Fe-S cluster biogenesis. Therefore, our studies are aimed at elucidating the factors that control GSH trafficking and metabolism in the model eukaryote Saccharomyces cerevisiae (baker’s yeast). Using …


Two Aspects Of Magnetic Nanoparticle Self-Assembly On Thin-Film Multilayers: Custom Media Properties And Accurate Determination Of Nanoparticle Anisotropy Constant, Sara L. Fitzgerald Jul 2021

Two Aspects Of Magnetic Nanoparticle Self-Assembly On Thin-Film Multilayers: Custom Media Properties And Accurate Determination Of Nanoparticle Anisotropy Constant, Sara L. Fitzgerald

Theses and Dissertations

ZFC/FC moment versus temperature measurements are a common technique to determine magnetic properties of nanoparticles. In this work, I varied both applied field strength and nanoparticle concentration to study resulting changes in blocking temperature, TB, and anisotropy constant, K. TB and K values were obtained using both existing and new analytic methods. Accurate determination of these parameters helps researchers optimize the use of magnetic nanoparticles for a variety of applications, including magnetic heating, drug delivery, and magnetic field-directed self-assembly. For magnetic self-assembly particularly, not only nanoparticle properties, but also the magnetic properties of the substrate alter …


Regression Methods For Group Testing Data, Michael Stutz Jul 2021

Regression Methods For Group Testing Data, Michael Stutz

Theses and Dissertations

Group testing is an efficient method of disease screening, whereby individual specimens (e.g., blood, urine, etc.) are pooled together and tested as a whole for the presence of disease. A common goal is to use data arising from these testing protocols to better understand the relationship between disease status and potential risk factors (e.g., age, symptom status, etc.). Numerous statistical methodologies have been developed for this purpose, most of which are built within the framework of a generalized linear model. Recent authors have suggested the inadequacy of such regression methods to capture the true functional relationships when nonlinear effects are …


Groundwater Flow And Transport At The Forest-Marsh Boundary: A Modeling Study, Sophia Chason Sanders Jul 2021

Groundwater Flow And Transport At The Forest-Marsh Boundary: A Modeling Study, Sophia Chason Sanders

Theses and Dissertations

The forest-marsh boundary, where tidally influenced salt marshes meet a forested upland, is hydrologically complex due to its multiple water inputs. Groundwater flow and salinity transport at this boundary are not well understood. In order to make predictions about salinity at this boundary as it responds to climatic factors, a two-dimensional model was built to simulate groundwater flow and solute transport at a salt marsh on Sapelo Island, Georgia. After calibration based on observed data from wells at the study site, the model can be used to identify patterns in groundwater movement and solute transport that may influence the vegetation …


Trimming Complexes, Keller Vandebogert Jul 2021

Trimming Complexes, Keller Vandebogert

Theses and Dissertations

We produce a family of complexes called trimming complexes and explore applications. We first study ideals defining type 2 compressed rings with socle minimally generated in degrees s and 2s − 1 for s > 2. We prove that all such ideals arise as trimmings of grade 3 Gorenstein ideals and show that trimming complexes yield an explicit free resolution. In particular, we give bounds on parameters arising in the Tor-algebra classification and construct explicit ideals attaining all intermediate values for every s. This partially answers a question of realizability of Tor-algebra structures posed by Avramov. Next, we study how …


Groundwater Discharge From Passive Continental Margins: Rethinking Marine Chemical Budgets, Andrew William Osborne Jul 2021

Groundwater Discharge From Passive Continental Margins: Rethinking Marine Chemical Budgets, Andrew William Osborne

Theses and Dissertations

Geothermal convection and sediment compaction drive large-scale flow in continental shelves. We suggest that this flow is an overlooked control on the major ion chemistry of the ocean. Conventional ocean chemical budgets are constructed using river discharge, axial mid-ocean ridge (MOR) convection and CaCO3 production, but these budgets are still poorly quantified. We synthesized data from 17 passive continental margin basins to calculate a range of estimated groundwater and chemical fluxes from continental shelves, considering five major ions (Ca2+, Na+, K+, Mg2+, and Cl-). When extrapolated globally, volumetric groundwater flux estimates were comparable to those for MOR axial circulation, and …


An Integrated Magneto-Electrochemical Device For The Rapid Profiling Of Tumour Extracellular Vesicles From Blood Plasma, Jongmin Park, Jun Seok Park, Chen Han Huang, Ala Jo, Kaitlyn Cook, Rui Wang, Hsing Ying Lin, Jan Van Deun, Huiyan Li, Jouha Min, Lan Wang, Ghilsuk Yoon, Bob S. Carter, Leonora Balaj, Gyu Seog Choi, Cesar M. Castro, Ralph Weissleder, Hakho Lee Jul 2021

An Integrated Magneto-Electrochemical Device For The Rapid Profiling Of Tumour Extracellular Vesicles From Blood Plasma, Jongmin Park, Jun Seok Park, Chen Han Huang, Ala Jo, Kaitlyn Cook, Rui Wang, Hsing Ying Lin, Jan Van Deun, Huiyan Li, Jouha Min, Lan Wang, Ghilsuk Yoon, Bob S. Carter, Leonora Balaj, Gyu Seog Choi, Cesar M. Castro, Ralph Weissleder, Hakho Lee

Statistical and Data Sciences: Faculty Publications

Assays for cancer diagnosis via the analysis of biomarkers on circulating extracellular vesicles (EVs) typically have lengthy sample workups, limited throughput or insufficient sensitivity, or do not use clinically validated biomarkers. Here we report the development and performance of a 96-well assay that integrates the enrichment of EVs by antibody-coated magnetic beads and the electrochemical detection, in less than one hour of total assay time, of EV-bound proteins after enzymatic amplification. By using the assay with a combination of antibodies for clinically relevant tumour biomarkers (EGFR, EpCAM, CD24 and GPA33) of colorectal cancer (CRC), we classified plasma samples from 102 …


Design And Implementation Of The Amiga Embedded System For Data Acquisition, A. Aab, P. Abreu, M. Aglietta, J. M. Albury, I. Allekotte, A. Almela, B. Fick, D. F. Nitz, A. Puyleart, Et. Al. Jul 2021

Design And Implementation Of The Amiga Embedded System For Data Acquisition, A. Aab, P. Abreu, M. Aglietta, J. M. Albury, I. Allekotte, A. Almela, B. Fick, D. F. Nitz, A. Puyleart, Et. Al.

Michigan Tech Publications

The Auger Muon Infill Ground Array (AMIGA) is part of the AugerPrime upgrade of the Pierre Auger Observatory. It consists of particle counters buried 2.3 m underground next to the water-Cherenkov stations that form the 23.5 km2 large infilled array. The reduced distance between detectors in this denser area allows the lowering of the energy threshold for primary cosmic ray reconstruction down to about 1017 eV. At the depth of 2.3 m the electromagnetic component of cosmic ray showers is almost entirely absorbed so that the buried scintillators provide an independent and direct measurement of the air showers muon content. …


Friedel Oscillations In Graphene Gapped By Breaking Ƥ And T Symmetries: Topological And Geometrical Signatures Of Electronic Structure, Jin Yang, Ding-Fu Shao, Shu-Hui Zhang, Wen Yang Jul 2021

Friedel Oscillations In Graphene Gapped By Breaking Ƥ And T Symmetries: Topological And Geometrical Signatures Of Electronic Structure, Jin Yang, Ding-Fu Shao, Shu-Hui Zhang, Wen Yang

Department of Physics and Astronomy: Faculty Publications

The measurement of Friedel oscillations (FOs) is conventionally used to recover the energy dispersion of electronic structure. Besides the energy dispersion, the modern electronic structure also embodies other key ingredients such as the geometrical and topological properties; it is one promising direction to explore the potential of FOs for the relevant measurement. Here, we present a comprehensive study of FOs in substrate-supported graphene under off-resonant circularly polarized light, in which a valley-contrasting feature and topological phase transition occur due to the combined breaking of inversion (Ƥ) and time reversal (T) symmetries. Depending on the position of …


Warm Jupiters In Tess Full-Frame Images: A Catalog And Observed Eccentricity Distribution For Year 1, J. Dong, C. X. Huang, R. I. Dawson, D. Foreman-Mackey, K. A. Collins, S. N. Quinn, J. J. Lissauer, T. Beatty, B. Quarles, L. Sha, A. Shporer, Z. Guo, S. R. Kane, L. Abe, K. Barkaoui, Z. Benkhaldoun, R. Brahm, F. Bouchy, T. W. Carmichael, K. I. Collins, D. M. Conti, N. Crouzet, G. Dransfield, P. Evans, T. Gan, M. Ghachoui, M. Gillon, N. Grieves, T. Guillot, C. Hellier, E. Jehin, Eric L.N. Jensen, A. Jordán, J. Kamler, J. F. Kielkopf, D. Mékarnia, L. D. Nielsen, F. J. Pozuelos, D. J. Radford, F.-X. Schmider, R. P. Schwarz, C. Stockdale, T.-G. Tan, M. Timmermans, A. H. M. J. Triaud, G. Wang, G. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. N. Winn, J. M. Jenkins, I. Mireles, D. A. Yahalomi, E. H. Morgan, M. Vezie, E. V. Quintana, M. E. Rose, J. C. Smith, B. Shiao Jul 2021

Warm Jupiters In Tess Full-Frame Images: A Catalog And Observed Eccentricity Distribution For Year 1, J. Dong, C. X. Huang, R. I. Dawson, D. Foreman-Mackey, K. A. Collins, S. N. Quinn, J. J. Lissauer, T. Beatty, B. Quarles, L. Sha, A. Shporer, Z. Guo, S. R. Kane, L. Abe, K. Barkaoui, Z. Benkhaldoun, R. Brahm, F. Bouchy, T. W. Carmichael, K. I. Collins, D. M. Conti, N. Crouzet, G. Dransfield, P. Evans, T. Gan, M. Ghachoui, M. Gillon, N. Grieves, T. Guillot, C. Hellier, E. Jehin, Eric L.N. Jensen, A. Jordán, J. Kamler, J. F. Kielkopf, D. Mékarnia, L. D. Nielsen, F. J. Pozuelos, D. J. Radford, F.-X. Schmider, R. P. Schwarz, C. Stockdale, T.-G. Tan, M. Timmermans, A. H. M. J. Triaud, G. Wang, G. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. N. Winn, J. M. Jenkins, I. Mireles, D. A. Yahalomi, E. H. Morgan, M. Vezie, E. V. Quintana, M. E. Rose, J. C. Smith, B. Shiao

Physics & Astronomy Faculty Works

Warm Jupiters—defined here as planets larger than 6 Earth radii with orbital periods of 8–200 days—are a key missing piece in our understanding of how planetary systems form and evolve. It is currently debated whether Warm Jupiters form in situ, undergo disk or high-eccentricity tidal migration, or have a mixture of origin channels. These different classes of origin channels lead to different expectations for Warm Jupiters' properties, which are currently difficult to evaluate due to the small sample size. We take advantage of the Transiting Exoplanet Survey Satellite (TESS) survey and systematically search for Warm Jupiter candidates around main-sequence host …


Smooth Global Approximation For Continuous Data Assimilation, Kenneth R. Brown Jul 2021

Smooth Global Approximation For Continuous Data Assimilation, Kenneth R. Brown

Theses and Dissertations

This thesis develops the finite element method, constructs local approximation operators, and bounds their error. Global approximation operators are then constructed with a partition of unity. Finally, an application of these operators to data assimilation of the two-dimensional Navier-Stokes equations is presented, showing convergence of an algorithm in all Sobolev topologies.


An Early Triassic Small Shelly Fossil-Style Assemblage From The Virgin Limestone Member, Moenkopi Formation, Western United States, Vivienne Maxwell, Ben Thuy, Sara B. Pruss Jul 2021

An Early Triassic Small Shelly Fossil-Style Assemblage From The Virgin Limestone Member, Moenkopi Formation, Western United States, Vivienne Maxwell, Ben Thuy, Sara B. Pruss

Geosciences: Faculty Publications

Small shelly fossils (SSFs) are minute fossils moulded or replaced by apatite, and less commonly, other minerals like glauconite and iron oxides. This taphonomic mode is best known from Cambrian deposits, though some occurrences occur across geological time. Instances of small shelly-style preservation were found in insoluble residues from the Lower Triassic Virgin Limestone Member exposed in southern Nevada, the western United States, a second such occurrence known from this unit. Fossil steinkerns of tiny brachiopods, echinoid spines and ophiuroids are fluorapatite, with scarce phosphatic internal moulds of bivalves and two replaced ostracods. In contrast, the crinoid ossicles, almost all …


Connectivism: Adopting Quantum Holism In International Relations, Grant Randal Highland Jul 2021

Connectivism: Adopting Quantum Holism In International Relations, Grant Randal Highland

Graduate Program in International Studies Theses & Dissertations

The current scientific context of both quantum science and an ever-increasingly connected global citizenry has set the conditions for a new perspective whereby the social sciences are on the cusp of adopting a quantum approach of probability and potentiality versus the clockwork mechanistic determinism of cause-and-effect Newtonian mechanics. While a scientific realist approach toward the application of quantum science to the social sciences is germane, there is a valid reason international relations should also consider and adopt the philosophical worldviews outside the genealogical canon of our early western forbears, as well as the philosophical explorations of consciousness and humanism which …


State Antifragility: An Agent-Based Modeling Approach To Understanding State Behavior, Rebecca Lee Law Jul 2021

State Antifragility: An Agent-Based Modeling Approach To Understanding State Behavior, Rebecca Lee Law

Graduate Program in International Studies Theses & Dissertations

This dissertation takes an interdisciplinary approach to understanding what makes states antifragile and why this matters by constructing a parsimonious, first of its kind agent-based model. The model focuses on the key elements of state antifragility that reside along a spectrum of fragility and transverse bidirectionally from fragile to resilient to antifragile given a certain set of environmental conditions.

First coined by Nicholas Nassim Taleb and applied to economics, antifragility is a nascent concept. In 2015, Nassim Taleb and Gregory Treverton’s article in Foreign Affairs outlined five characteristics of state antifragility. This project aims to advance the study of anti-fragility …


Monarch Science Observer, Volume 10, College Of Sciences, Old Dominion University Jul 2021

Monarch Science Observer, Volume 10, College Of Sciences, Old Dominion University

College of Sciences Newsletter

Summer 2021 issue of Monarch Science Observer, ODU College of Sciences Newsletter.


The Design Of A Framework For The Detection Of Web-Based Dark Patterns, Andrea Curley, Dympna O'Sullivan, Damian Gordon, Brendan Tierney, Ioannis Stavrakakis Jul 2021

The Design Of A Framework For The Detection Of Web-Based Dark Patterns, Andrea Curley, Dympna O'Sullivan, Damian Gordon, Brendan Tierney, Ioannis Stavrakakis

Conference Papers

In the theories of User Interfaces (UI) and User Experience (UX), the goal is generally to help understand the needs of users and how software can be best configured to optimize how the users can interact with it by removing any unnecessary barriers. However, some systems are designed to make people unwillingly agree to share more data than they intend to, or to spend more money than they plan to, using deception or other psychological nudges. User Interface experts have categorized a number of these tricks that are commonly used and have called them Dark Patterns. Dark Patterns are varied …


A Differentially Private Task Planning Framework For Spatial Crowdsourcing, Qian Tao, Yongxin Tong, Shuyuan Li, Yuxiang Zeng, Zimu Zhou, Ke Xu Jul 2021

A Differentially Private Task Planning Framework For Spatial Crowdsourcing, Qian Tao, Yongxin Tong, Shuyuan Li, Yuxiang Zeng, Zimu Zhou, Ke Xu

Research Collection School Of Computing and Information Systems

Spatial crowdsourcing has stimulated various new applications such as taxi calling and food delivery. A key enabler for these spatial crowdsourcing based applications is to plan routes for crowd workers to execute tasks given diverse requirements of workers and the spatial crowdsourcing platform. Despite extensive studies on task planning in spatial crowdsourcing, few have accounted for the location privacy of tasks, which may be misused by an untrustworthy platform. In this paper, we explore efficient task planning for workers while protecting the locations of tasks. Specifically, we define the Privacy-Preserving Task Planning (PPTP) problem, which aims at both total revenue …


Trust In And Ethical Design Of Carebots: The Case For Ethics Of Care, Gary Kok Yew Chan Jul 2021

Trust In And Ethical Design Of Carebots: The Case For Ethics Of Care, Gary Kok Yew Chan

Research Collection Yong Pung How School Of Law

The paper has two main objectives: to examine the challenges arising from the use of carebots as well as to discuss how the design of carebots can deal with these challenges. First, it notes that the use of carebots to take care of the physical and mental health of the elderly, children and the disabled as well as to serve as assistive tools and social companions encounter a few main challenges. They relate to the extent of the care robots’ ability to care for humans, potential deception by robot morphology and communications, (over)reliance on or attachment to robots, and the …


Resonant Two-Photon Ionization And Velocity Mapped Ion Imaging Studies Of Aromatic Van Der Waals Complexes, James T. Makuvaza Jul 2021

Resonant Two-Photon Ionization And Velocity Mapped Ion Imaging Studies Of Aromatic Van Der Waals Complexes, James T. Makuvaza

Dissertations (1934 -)

The study of van der Waals complexes provides a means for understanding the nature and strength of non-covalent interactions. Non-covalent interactions including C-H/, C-H/O, C-H/N, C-H/F, halogen and chalcogen bonding are found in important intermediates that regulate chemical and biological processes in many forefront areas of science including molecular self-assembly, drug substrate interactions, supramolecular chemistry, crystal engineering and biochemistry. To better understand these interactions, laser spectroscopic techniques that include mass selected two color resonant two photon ionization (2CR2PI) and velocity mapped ion imaging spectroscopy in combination with complementary ab initio calculations were used to probe the electronic structure, geometries, and …


Sepsis Monitoring Using Contextually-Tailored Online Change Point Detection And Beyond, Nazmus Sakib Jul 2021

Sepsis Monitoring Using Contextually-Tailored Online Change Point Detection And Beyond, Nazmus Sakib

Dissertations (1934 -)

Considering morbidity, mortality, and annual treatment costs, the dramatic rise in the incidence of sepsis and septic shock among intensive care unit (ICU) admissions in US hospitals is an increasing concern. The recent excruciating statistics regarding sepsis mortality, the average length of hospital stay, and annual treatment costs made sepsis treatment and research a critical domain in medical informatics. The aims of this dissertation center around four research questions. First, we discuss how we can investigate the prevalence and underlying relation of the sepsis diagnosis criteria (qSOFA and SIRS) and its implications in Medical Informatics and predictive analytics. Second, we …


Improved Motor Imagery Decoding Using Deep Learning Techniques, Olawunmi Olaboopo George Jul 2021

Improved Motor Imagery Decoding Using Deep Learning Techniques, Olawunmi Olaboopo George

Dissertations (1934 -)

Motor imagery (MI) has been one of the most used paradigms for building brain-computer interfaces (BCI), widely used in neurorehabilitation, for restoring functionality to damaged parts of a neurologically deficient person. The existing motor imagery techniques have largely employed feature extraction techniques such as the power spectral density (PSD) and the common spatial patterns (CSP) before classification, using traditional machine learning algorithms such as support vector machines (SVM) and linear discriminant analysis (LDA). These algorithms are quite limited in their ability to generate feature representations for certain types of signals, limiting the potential for improvements in the decoding process. Also, …


Simplified Volcano Hazard Maps: Two Groups User-Experience (Ux) Study Results, Rachel Volentine Jul 2021

Simplified Volcano Hazard Maps: Two Groups User-Experience (Ux) Study Results, Rachel Volentine

User eXperience Lab

The purpose of this research is to identify any usability issues and opportunities to improve the design for superb communication of volcanic hazards and risks. From this research, insights into the intuitiveness and risk-communication deficiencies of these hazard maps will help create a new methodology for evaluation map-based communication products implemented by USGS and its partners/stakeholders, Risk COP members, and practitioners around the world to alleviate volcanic risk and hazards.


Determinantal Quantum Monte Carlo Solver For Cluster Perturbation Theory, Edwin W. Huang, Yao Wang Jul 2021

Determinantal Quantum Monte Carlo Solver For Cluster Perturbation Theory, Edwin W. Huang, Yao Wang

Open Access Publishing Fund

Cluster Perturbation Theory (CPT) is a technique for computing the spectral function of fermionic models with local interactions. By combining the solution of the model on a finite cluster with perturbation theory on intra-cluster hoppings, CPT provides access to single-particle properties with arbitrary momentum resolution while incurring low computational cost. Here, we introduce Determinantal Quantum Monte Carlo (DQMC) as a solver for CPT. Compared to the standard solver, exact diagonalization (ED), the DQMC solver reduces finite size effects through utilizing larger clusters, allows study of temperature dependence, and enables large-scale simulations of a greater set of models. We discuss the …


Estimating Turbulence Distribution Over A Heterogeneous Path Using Time‐Lapse Imagery From Dual Cameras, Benjamin Wilson, Santasri Bose-Pillai, Jack E. Mccrae, Kevin J. Keefer, Steven T. Fiorino Jul 2021

Estimating Turbulence Distribution Over A Heterogeneous Path Using Time‐Lapse Imagery From Dual Cameras, Benjamin Wilson, Santasri Bose-Pillai, Jack E. Mccrae, Kevin J. Keefer, Steven T. Fiorino

Faculty Publications

Knowledge of turbulence distribution along an experimental path can help in effective turbulence compensation and mitigation. Although scintillometers are traditionally used to measure the strength of turbulence, they provide a path-integrated measurement and have limited operational ranges. A technique to profile turbulence using time-lapse imagery of a distant target from spatially separated cameras is presented here. The method uses the turbulence induced differential motion between pairs of point features on a target, sensed at a single camera and between cameras to extract turbulence distribution along the path. The method is successfully demonstrated on a 511 m almost horizontal path going …


Crosssections, Summer 2021, University Of Northern Iowa. Department Of Physics. Jul 2021

Crosssections, Summer 2021, University Of Northern Iowa. Department Of Physics.

CrossSections

In This Issue:

A Message from the Department Head --- 1
Faculty Profile: Dr. Paul Shand --- 3
Department Happenings --- 4
Student Focus --- 6
Student Research --- 8
Alumni Profile --- 9
Alumni News --- 10
Science Education --- 11
In Memoriam --- 12
New Physics --- 15


Observation Of Gravitational Waves From Two Neutron Star-Black Hole Coalescences, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, K. Ackley, A. Adams, C. Adams, R. X. Adhikari, V. B. Adya, C. Affeldt, D. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, T. Akutsu, Tiffany Z. Summerscales Jul 2021

Observation Of Gravitational Waves From Two Neutron Star-Black Hole Coalescences, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, K. Ackley, A. Adams, C. Adams, R. X. Adhikari, V. B. Adya, C. Affeldt, D. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, T. Akutsu, Tiffany Z. Summerscales

Faculty Publications

We report the observation of gravitational waves from two compact binary coalescences in LIGO's and Virgo's third observing run with properties consistent with neutron star-black hole (NSBH) binaries. The two events are named GW200105_162426 and GW200115_042309, abbreviated as GW200105 and GW200115; the first was observed by LIGO Livingston and Virgo and the second by all three LIGO-Virgo detectors. The source of GW200105 has component masses, whereas the source of GW200115 has component masses and (all measurements quoted at the 90% credible level). The probability that the secondary's mass is below the maximal mass of a neutron star is 89%-96% and …


Particle Acceleration At The Discontinuous Flow Boundary Of Collimated Cylindrical Jets, Stephen O'Sullivan, Andrew M. Taylor, Brian Reville Jul 2021

Particle Acceleration At The Discontinuous Flow Boundary Of Collimated Cylindrical Jets, Stephen O'Sullivan, Andrew M. Taylor, Brian Reville

Conference Papers

We revisit the issue of particle acceleration at the interface between a collimated laminar jet and a static ambient medium. The contrast between standard diffusive scattering treatments and anomalous transport in synthetic field constructions is explored. A particular emphasis is placed on the necessity for physically consistent particle transport considerations. The temporal, spatial and spectral features of the process are discussed, in the context of potential UHECR production, as well as further observational consequences.