Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

2020

Old Dominion University

Discipline
Keyword
Publication
Publication Type
File Type

Articles 1 - 30 of 269

Full-Text Articles in Physical Sciences and Mathematics

Fundamentals Of Human-Centric Artificial Intelligence (A.I.): Comparative Analysis Of Europe And The U. S. Landscape, Torré A. Williams Dec 2020

Fundamentals Of Human-Centric Artificial Intelligence (A.I.): Comparative Analysis Of Europe And The U. S. Landscape, Torré A. Williams

Cybersecurity Undergraduate Research Showcase

This research is a comparative analysis of human-centric Artificial Intelligence (A.I.) in Europe and the U.S. This research establishes fundamentals that are critical to what makes A.I. human-centric. This research contains eight phases: 1) Lawful A.I.; 2) Robust A.I.; 3) Ethical A.I.; 4) Human-centric A.I.; 5) Current State of A.I.; 6) A.I. in Europe; 7) A.I. in the U.S.; 9) Importance of Human-centric A.I. This research shows that there are still ongoing changes with having a human-centric A.I. and why it is very important to society. This research is the beginning of the making of a successful and reliable human-centric …


Monarch Science Observer, Volume 7, College Of Sciences, Old Dominion University Dec 2020

Monarch Science Observer, Volume 7, College Of Sciences, Old Dominion University

College of Sciences Newsletter

December-Fall 2020 issue of Monarch Science Observer, ODU College of Sciences Newsletter.


The Role Of Traditional Knowledge In Coastal Adaptation Priorities: The Pamunkey Indian Reservation, Nicole S. Hutton, Thomas R. Allen Dec 2020

The Role Of Traditional Knowledge In Coastal Adaptation Priorities: The Pamunkey Indian Reservation, Nicole S. Hutton, Thomas R. Allen

Political Science & Geography Faculty Publications

Coastal reservations are increasingly vulnerable to hazards exacerbated by climate change. Resources for restoration projects are limited. Storm surge, storms, tidal flooding, and erosion endanger artifacts and limit livelihoods of tribes in coastal Virginia. GIS offers a platform to increase communication between scientists, planners, and indigenous groups. The Pamunkey Indian Tribe engaged in a participatory mapping exercise to assess the role of traditional ecological knowledge (TEK) in coastal management decision-making and its capacity to address flooding. Priorities and strategies were spatially referenced using maps of potential sea level rise for 2040, 2060, and 2080, input into a resilience matrix to …


Wicked Ideas For Wicked Problems: Marine Debris And The Complexity Of Governance, Dawn Helene Driesbach Dec 2020

Wicked Ideas For Wicked Problems: Marine Debris And The Complexity Of Governance, Dawn Helene Driesbach

Graduate Program in International Studies Theses & Dissertations

Myriad challenges regarding earth's common spaces, those unregulated by sovereign state authorities, mount and intensify as resources diminish and competition for commercial, scientific and security advantages increases; the pollution and degradation of those spaces simultaneously expands. Threats to the global commons complicate efforts to achieve international consensus which impedes attempts to develop effective governance. As an example, marine debris is a growing problem and is an existential threat to the global commons.

This dissertation aims to characterize marine debris as a wicked problem and explores the complexity of governance in the global ocean commons by answering two fundamental questions. Under …


Parton Distribution Functions From Ioffe Time Pseudodistributions From Lattice Calculations: Approaching The Physical Point, Bálint Joó, Joseph Karpie, Kostas Orginos, Anatoly V. Radyushkin, David G. Richards, Savvas Zafeiropoulos Dec 2020

Parton Distribution Functions From Ioffe Time Pseudodistributions From Lattice Calculations: Approaching The Physical Point, Bálint Joó, Joseph Karpie, Kostas Orginos, Anatoly V. Radyushkin, David G. Richards, Savvas Zafeiropoulos

Physics Faculty Publications

We present results for the unpolarized parton distribution function of the nucleon computed in lattice QCD at the physical pion mass. This is the first study of its kind employing the method of Ioffe time pseudodistributions. Beyond the reconstruction of the Bjorken-x dependence, we also extract the lowest moments of the distribution function using the small Ioffe time expansion of the Ioffe time pseudodistribution. We compare our findings with the pertinent phenomenological determinations.


Internet Of Things (Iot): Cybersecurity Risks In Healthcare, Ruhi Patel Dec 2020

Internet Of Things (Iot): Cybersecurity Risks In Healthcare, Ruhi Patel

Cybersecurity Undergraduate Research Showcase

The rapid growth and investment in the Internet of Things (IoT) has significantly impacted how individuals and industries operate. The Internet of Things (IoT) refers to a network of physical, technology-embedded objects that communicate, detect, and interact with their external environment or internal state (Hung, 2017). According to Tankovska (2020), IoT devices are estimated to reach 21.5 billion units by 2025. This technological boom is leading various industrial sectors to notice a quick increase in cybersecurity risks and threats. One industrial sector has been particularly vulnerable to numerous cyber threats across the globe: healthcare. Oliver Noble (2020), a data encryption …


Assessment Of Factors Influencing Migratory Landbird Use Of Forested Stopover Sites Along The Delmarva Peninsula During Autumn Migration, J. Andrew Arnold Dec 2020

Assessment Of Factors Influencing Migratory Landbird Use Of Forested Stopover Sites Along The Delmarva Peninsula During Autumn Migration, J. Andrew Arnold

Biological Sciences Theses & Dissertations

Autumn migration is a time when billions of birds move from breeding grounds in North America to wintering grounds in Central and South America, with many individuals relying on stopover habitats en route for resting and refueling purposes. These stopover sites are critical to the survival of the hundreds of species of migratory landbirds that migrate annually, and thus identifying important stopover sites is a high priority for conserving such taxa. The Delmarva Peninsula; a coastal region of Delaware, Maryland, and Virginia along the mid-Atlantic flyway; consists of forested habitats with ample food and shelter that likely serves as quality …


Global Conservation Status Of Croaker And Drum (Family: Sciaenidae) And Role Of The Maw Trade, Claire E. Gorman Dec 2020

Global Conservation Status Of Croaker And Drum (Family: Sciaenidae) And Role Of The Maw Trade, Claire E. Gorman

Biological Sciences Theses & Dissertations

Understanding threats and drivers of extinction risk is critical to conserving marine biodiversity. Although marine bony fishes are some of the most diverse and abundant vertebrates in the world, overexploitation is the major threat to these taxa. Species in the family Sciaenidae are important marine resources in many parts of the world, supporting small- and large-scale fisheries for consumption and the international maw (dried swimbladder) trade. Sciaenids exhibit a diverse array of life history characteristics, such as high fecundity, large body size, formation of spawning aggregations, and longevity. Some characteristics increase their susceptibility to anthropogenic stressors. Despite being ecologically and …


Not Too Hot, Not Too Cold, But Moderately Variable: The Influence Of Environmental Variability On Coral Thermal Tolerance, Courtney Nicole Klepac Dec 2020

Not Too Hot, Not Too Cold, But Moderately Variable: The Influence Of Environmental Variability On Coral Thermal Tolerance, Courtney Nicole Klepac

Biological Sciences Theses & Dissertations

Anthropogenic climate change is causing an increase in the frequency and severity of marine heat waves, resulting in declining health of coral reef ecosystems worldwide. Coral bleaching events – the breakdown in symbiosis between the coral host and their intracellular photosynthetic algae – are increasingly common in recent years and contribute to widespread losses in coral cover. However, bleaching and heat stress responses vary across spatial scales both within and among coral species. Coral populations native to highly variable environments can have greater bleaching resistance than corals from more stable habitats and corals transplanted into these variable reef sites can …


Parallelization Of The Advancing Front Local Reconnection Mesh Generation Software Using A Pseudo-Constrained Parallel Data Refinement Method, Kevin Mark Garner Jr. Dec 2020

Parallelization Of The Advancing Front Local Reconnection Mesh Generation Software Using A Pseudo-Constrained Parallel Data Refinement Method, Kevin Mark Garner Jr.

Computer Science Theses & Dissertations

Preliminary results of a long-term project entailing the parallelization of an industrial strength sequential mesh generator, called Advancing Front Local Reconnection (AFLR), are presented. AFLR has been under development for the last 25 years at the NSF/ERC center at Mississippi State University. The parallel procedure that is presented is called Pseudo-constrained (PsC) Parallel Data Refinement (PDR) and consists of the following steps: (i) use an octree data-decomposition scheme to divide the original geometry into subdomains (octree leaves), (ii) refine each subdomain with the proper adjustments of its neighbors using the given refinement code, and (iii) combine all subdomain data into …


Inference And Estimation In Change Point Models For Censored Data, Kristine Gierz Dec 2020

Inference And Estimation In Change Point Models For Censored Data, Kristine Gierz

Mathematics & Statistics Theses & Dissertations

In general, the change point problem considers inference of a change in distribution for a set of time-ordered observations. This has applications in a large variety of fields and can also apply to survival data. With improvements to medical diagnoses and treatments, incidences and mortality rates have changed. However, the most commonly used analysis methods do not account for such distributional changes. In survival analysis, change point problems can concern a shift in a distribution for a set of time-ordered observations, potentially under censoring or truncation.

In this dissertation, we first propose a sequential testing approach for detecting multiple change …


Mementomap: A Web Archive Profiling Framework For Efficient Memento Routing, Sawood Alam Dec 2020

Mementomap: A Web Archive Profiling Framework For Efficient Memento Routing, Sawood Alam

Computer Science Theses & Dissertations

With the proliferation of public web archives, it is becoming more important to better profile their contents, both to understand their immense holdings as well as to support routing of requests in Memento aggregators. A memento is a past version of a web page and a Memento aggregator is a tool or service that aggregates mementos from many different web archives. To save resources, the Memento aggregator should only poll the archives that are likely to have a copy of the requested Uniform Resource Identifier (URI). Using the Crawler Index (CDX), we generate profiles of the archives that summarize their …


Climate Change Games As Boundary Objects: Fostering Dialogic Communication Within Stakeholder Engagement, Megan L. Mckittrick Dec 2020

Climate Change Games As Boundary Objects: Fostering Dialogic Communication Within Stakeholder Engagement, Megan L. Mckittrick

English Theses & Dissertations

Rising waters and the increasing devastation of flood events make coastal resilience a significant issue in the Hampton Roads region of Virginia, particularly in the city of Norfolk. Enhancing resilience requires ongoing stakeholder engagement designed to invite dialogue while encouraging cross-jurisdictional collaboration and comprehensive problem-solving. Climate change games have been employed to support these endeavors. This dissertation provides a response to the following research questions: 1) What is the origin of the climate change game genre? 2) Why are key stakeholders in coastal resilience using climate change games? And 3) how do these games operate for these key stakeholders? To …


Measurement Of Pion-Pion Final State Interactions In Η → Π +Π −Γ With Clas At Jefferson Lab, Torri C. Jeske Dec 2020

Measurement Of Pion-Pion Final State Interactions In Η → Π +Π −Γ With Clas At Jefferson Lab, Torri C. Jeske

Physics Theses & Dissertations

Decays of pseudoscalar mesons proceed from the chiral anomaly, which arises from spontaneous chiral symmetry breaking. In the limit of massless quarks (chiral limit), the η → π +π −γ the decay width is determined solely by the box anomaly term in the Wess Zumino Witten Lagrangian. Since the physical quarks are not massless, the decay region of the η meson is far from the chiral limit and thus proper inclusion of the momentum dependence is essential to reproduce the measured decay width. Several theoretical frameworks have been proposed to describe these interactions. We report a new measurement of the …


Synthesis, Characterization, Spectroscopic, And Mesomorphic Studies Of New Schiff Base Ligands And Titanium, Cobalt, Nickel And Copper Metal Centers, Raj K. Gurung Dec 2020

Synthesis, Characterization, Spectroscopic, And Mesomorphic Studies Of New Schiff Base Ligands And Titanium, Cobalt, Nickel And Copper Metal Centers, Raj K. Gurung

Chemistry & Biochemistry Theses & Dissertations

Transition metal complexes with Schiff base ligands offer a wide application in the field of development of catalysis and material. The straightforward synthesis allowed the structural modification and helped to optimize in various application of such complexes. Titanium-containing complexes have been reported to be important for their catalytic and material applications through the coordination of a tetradentate Schiff base ligand, viz. N, N’-ethylene bis(salicylideneiminate) dianion (salen). Studies reporting the characterization of achiral titanium(IV) salen complexes are scarce due to their intricate nature. Such complexes would be comparatively less expensive and easier to prepare synthetically and thus could represent an …


Constraining Respired Carbon Storage In The Eastern Tropical Pacific Over The Last 25 Thousand Years Using Benthic Foraminiferal Boron/Calcium Ratios, Brian James Close Dec 2020

Constraining Respired Carbon Storage In The Eastern Tropical Pacific Over The Last 25 Thousand Years Using Benthic Foraminiferal Boron/Calcium Ratios, Brian James Close

OES Theses and Dissertations

The storage of inorganic carbon in the deep Pacific Ocean is thought to play an important role in regulating both glacial-interglacial and millennial-scale atmospheric CO2 concentrations (Broecker and Barker 2007; Sigman et al., 2010). A recent study by Loveley et al. (2017) showed that sedimentary authigenic uranium (aU) concentrations, a proxy for suboxic bottom-water conditions, increased significantly in the Eastern Equatorial Pacific (EEP) during the Last Glacial Maximum (LGM, 18 kyr – 23 kyr). If this is correct, the low-oxygen, CO2-rich waters would also have a lower pH and a lower carbonate ion concentration ([CO32- …


Enhanced Traffic Incident Analysis With Advanced Machine Learning Algorithms, Zhenyu Wang Dec 2020

Enhanced Traffic Incident Analysis With Advanced Machine Learning Algorithms, Zhenyu Wang

Computational Modeling & Simulation Engineering Theses & Dissertations

Traffic incident analysis is a crucial task in traffic management centers (TMCs) that typically manage many highways with limited staff and resources. An effective automatic incident analysis approach that can report abnormal events timely and accurately will benefit TMCs in optimizing the use of limited incident response and management resources. During the past decades, significant efforts have been made by researchers towards the development of data-driven approaches for incident analysis. Nevertheless, many developed approaches have shown limited success in the field. This is largely attributed to the long detection time (i.e., waiting for overwhelmed upstream detection stations; meanwhile, downstream stations …


In The Margins: Reconsidering The Range And Contribution Of Diazotrophs In Nearshore Environments, Corday R. Selden Dec 2020

In The Margins: Reconsidering The Range And Contribution Of Diazotrophs In Nearshore Environments, Corday R. Selden

OES Theses and Dissertations

Dinitrogen (N2) fixation enables primary production and, consequently, carbon dioxide drawdown in nitrogen (N) limited marine systems, exerting a powerful influence over the coupled carbon and N cycles. Our understanding of the environmental factors regulating its distribution and magnitude are largely based on the range and sensitivity of one genus, Trichodesmium. However, recent work suggests that the niche preferences of distinct diazotrophic (N2 fixing) clades differ due to their metabolic and ecological diversity, hampering efforts to close the N budget and model N2 fixation accurately. Here, I explore the range of N2 fixation …


Synthesis And Characterization Of Carbohydrate Based Molecular Gelators And Macrocycles Through Cycloaddition Reactions, Dan Wang Dec 2020

Synthesis And Characterization Of Carbohydrate Based Molecular Gelators And Macrocycles Through Cycloaddition Reactions, Dan Wang

Chemistry & Biochemistry Theses & Dissertations

Carbohydrate based low molecular weight gelators (LMWGs) are biocompatible and have many potential applications. They have been used for drug delivery, environmental clean-up, and for reaction catalysis. In recent years, copper catalyzed azide alkyne cycloaddition reactions (CuAACs) also termed “Click reactions” have shown great applications in the synthesis of various glycoconjugates and carbohydrate derivatives.

In this research, three diverse classes of glycoconjugates (I, II, III) have been designed and synthesized. The first class of compounds (I) in Chapter 2 are D-glucosamine based amide and triazole derivatives with different spacers between the amide and triazole (n=2-5) function groups. These compounds were …


Advances In The Understanding Of Sourcing And Fate Of Pyrogenic Organic Matter In The Environment, Aleksandar Ivaylov Goranov Dec 2020

Advances In The Understanding Of Sourcing And Fate Of Pyrogenic Organic Matter In The Environment, Aleksandar Ivaylov Goranov

Chemistry & Biochemistry Theses & Dissertations

With higher occurrences of forest fires worldwide, there has been an increase in scientific interest surrounding the chemistry of pyrogenic organic matter (pyOM). The main structural components of pyOM, the condensed aromatic compounds (ConAC), exhibit intriguing physico-chemical properties and have been one of the main focuses of biogeochemical research. The overwhelmingly large number of scientific articles regarding pyOM and ConAC are guided by the assumption that ConAC in the environment are exclusively of pyrogenic origin, even though some recent studies have suggested that some of these ConAC could also be derived from non-pyrogenic radical-driven processes. To evaluate this controversial proposition, …


Deeply Virtual Compton Scattering At Hall A, Jefferson Lab, Mohamed Nuhman Hashir Rashad Dec 2020

Deeply Virtual Compton Scattering At Hall A, Jefferson Lab, Mohamed Nuhman Hashir Rashad

Physics Theses & Dissertations

The Standard Model of particle physics defines quarks and leptons as the basic building blocks of all matter. The interaction between them are mediated by force carrying gauge bosons. Quantum ChromoDynamics (QCD), the theory that explains the strong interaction is still not complete enough to derive the physical observables of a Quark-Gluon system from the fundamental degrees of freedom of it’s constituents. Experimentally observable single particle densities provide important insights into our understanding of the quark-gluon system and hence help fill in the gaps of QCD. Generalized Parton Distributions (GPDs) provide simultaneous information of both spacial and longitudinal momentum distributions …


Synthesis, Characterization, And Kinetics Studies Of New Cobalt Complexes For The Production Of H2 In Acidic Media, Michael John Celestine Dec 2020

Synthesis, Characterization, And Kinetics Studies Of New Cobalt Complexes For The Production Of H2 In Acidic Media, Michael John Celestine

Chemistry & Biochemistry Theses & Dissertations

The kinetics and mechanism of the oxidation of [Co(dmgBF2)2(OH2)2] (where dmgBF2 = difluoroboryldimethylglyoximato) by sodium hypochlorite (NaOCl), sodium bromate (NaBrO3), and bromine (Br2) was investigated by stopped-flow spectrophotometry at 450 nm over a wide temperature range. The pKa1 value for [Co(dmgBF2)2(OH2)2] was calculated as 5.27 ± 0.14 at I = 0.60 (NaCl). From the variation in pH studies, the activation parameters were derived from the proposed mechanisms for NaOCl, ΔH1*, ΔH2*, ΔS1*, and …


Sodium-Calcium Ratios In The Planktic Foraminifera Trilobatus Sacculifer As A Proxy For Sea Surface Salinity, Colton Steele Watkins Dec 2020

Sodium-Calcium Ratios In The Planktic Foraminifera Trilobatus Sacculifer As A Proxy For Sea Surface Salinity, Colton Steele Watkins

OES Theses and Dissertations

Recent culture and field studies have found a significant positive correlation between seawater salinity and the incorporation of sodium into foraminiferal calcite, suggesting a potential new proxy for reconstructing past changes in sea surface salinity (SSS) (Mezger et al., 2016 and Bertlich et al., 2018). In order to test the applicability of this new proxy in an open-ocean setting, Na/Ca ratios in the planktic foraminifera Trilobatus sacculifer (T. sacculifer Na/Ca) were measured from a suite of sediment core tops spanning a natural salinity gradient from the North Atlantic subtropical gyre to the South Atlantic subtropical gyre. Initial results from …


The Effects Of Security Framing, Time Pressure, And Brand Familiarity On Risky Mobile Application Downloads, Cody Parker Dec 2020

The Effects Of Security Framing, Time Pressure, And Brand Familiarity On Risky Mobile Application Downloads, Cody Parker

Psychology Theses & Dissertations

The current study examined the effects of security system framing, time pressure, and brand familiarity on mobile application download behaviors, with an emphasis on risk taking. According to the Prospect Theory, people tend to engage in irrational decision making, and make qualitatively different decisions when information is framed in terms of gains and losses (i.e., the framing effect). Past research has used this framing effect to guide the design of a risk display for mobile applications (apps), with the purpose of communicating the potential risks and minimizing insecure app selections. Time pressure has been shown to influence the framing effect …


Conical Orbital Mechanics: A Rework Of Classic Orbit Transfer Mechanics, Cian Anthony Branco Dec 2020

Conical Orbital Mechanics: A Rework Of Classic Orbit Transfer Mechanics, Cian Anthony Branco

Mechanical & Aerospace Engineering Theses & Dissertations

Simple orbital maneuvers obeying Kepler’s Laws, when taken with respect to Newton’s framework, require considerable time and effort to interpret and understand. Instead of a purely mathematical approach relying on the governing relations, a graphical geometric conceptual representation provides a useful alternative to the physical realities of orbits. Conic sections utilized within the full scope of a modified cone (frustum) were employed to demonstrate and develop a geometric approach to elliptical orbit transformations. The geometric model in-question utilizes the rotation of a plane intersecting the orbital frustum at some angle β (and the change in this angle) in a novel …


Onboard Autonomous Controllability Assessment For Fixed Wing Suavs, Brian Edward Duvall Dec 2020

Onboard Autonomous Controllability Assessment For Fixed Wing Suavs, Brian Edward Duvall

Mechanical & Aerospace Engineering Theses & Dissertations

Traditionally fixed-wing small Unmanned Arial Vehicles (sUAV) are flown while in direct line of sight with commands from a remote operator. However, this is changing with the increased popularity and ready availability of low-cost flight controllers. Flight controllers provide fixed-wing sUAVs with functions that either minimize or eliminate the need for a remote operator. Since the remote operator is no longer controlling the sUAV, it is impossible to determine if the fixed-wing sUAV has proper control authority. In this work, a controllability detection system was designed, built, and flight-tested using COTS hardware. The method features in-situ measurement and analysis of …


Autonomous Vehicles And The Ethical Tension Between Occupant And Non-Occupant Safety, Jason Borenstein, Joseph Herkert, Keith Miller Nov 2020

Autonomous Vehicles And The Ethical Tension Between Occupant And Non-Occupant Safety, Jason Borenstein, Joseph Herkert, Keith Miller

The Journal of Sociotechnical Critique

Given that the creation and deployment of autonomous vehicles is likely to continue, it is important to explore the ethical responsibilities of designers, manufacturers, operators, and regulators of the technology. We specifically focus on the ethical responsibilities surrounding autonomous vehicles that these stakeholders have to protect the safety of non-occupants, meaning individuals who are around the vehicles while they are operating. The term “non-occupants” includes, but is not limited to, pedestrians and cyclists. We are particularly interested in how to assign moral responsibility for the safety of non-occupants when autonomous vehicles are deployed in a complex, land-based transportation system.


Potential Virus-Mediated Nitrogen Cycling In Oxygen-Depleted Oceanic Waters, M. Consuelo Gazitúa, Dean R. Vik, Simon Roux, Ann C. Gregory, Benjamin Bolduc, Brittany Widner, Margaret R. Mulholland, Steven J. Hallam, Osvaldo Ulloa, Matthew B. Sullivan Nov 2020

Potential Virus-Mediated Nitrogen Cycling In Oxygen-Depleted Oceanic Waters, M. Consuelo Gazitúa, Dean R. Vik, Simon Roux, Ann C. Gregory, Benjamin Bolduc, Brittany Widner, Margaret R. Mulholland, Steven J. Hallam, Osvaldo Ulloa, Matthew B. Sullivan

OES Faculty Publications

Viruses play an important role in the ecology and biogeochemistry of marine ecosystems. Beyond mortality and gene transfer, viruses can reprogram microbial metabolism during infection by expressing auxiliary metabolic genes (AMGs) involved in photosynthesis, central carbon metabolism, and nutrient cycling. While previous studies have focused on AMG diversity in the sunlit and dark ocean, less is known about the role of viruses in shaping metabolic networks along redox gradients associated with marine oxygen minimum zones (OMZs). Here, we analyzed relatively quantitative viral metagenomic datasets that profiled the oxygen gradient across Eastern Tropical South Pacific (ETSP) OMZ waters, assessing whether OMZ …


Under-Ice Phytoplankton Blooms: Shedding Light On The "Invisible" Part Of Arctic Primary Production, Mathieu Ardyna, C. J. Mundy, Nicolas Mayot, Lisa C. Matthes, Laurent Oziel, Christopher Horvat, Eva Leu, Philipp Assmy, Victoria Hill, Patricia A. Matrai, Matthew Gale, Igor A. Melnikov, Kevin R. Arrigo Nov 2020

Under-Ice Phytoplankton Blooms: Shedding Light On The "Invisible" Part Of Arctic Primary Production, Mathieu Ardyna, C. J. Mundy, Nicolas Mayot, Lisa C. Matthes, Laurent Oziel, Christopher Horvat, Eva Leu, Philipp Assmy, Victoria Hill, Patricia A. Matrai, Matthew Gale, Igor A. Melnikov, Kevin R. Arrigo

OES Faculty Publications

The growth of phytoplankton at high latitudes was generally thought to begin in open waters of the marginal ice zone once the highly reflective sea ice retreats in spring, solar elevation increases, and surface waters become stratified by the addition of sea-ice melt water. In fact, virtually all recent large-scale estimates of primary production in the Arctic Ocean (AO) assume that phytoplankton production in the water column under sea ice is negligible. However, over the past two decades, an emerging literature showing significant under-ice phytoplankton production on a pan-Arctic scale has challenged our paradigms of Arctic phytoplankton ecology and phenology. …


Deepfrag-K: A Fragment-Based Deep Learning Approach For Protein Fold Recognition, Wessam Elhefnawy, Min Li, Jianxin Wang, Yaohang Li Nov 2020

Deepfrag-K: A Fragment-Based Deep Learning Approach For Protein Fold Recognition, Wessam Elhefnawy, Min Li, Jianxin Wang, Yaohang Li

Computer Science Faculty Publications

Background: One of the most essential problems in structural bioinformatics is protein fold recognition. In this paper, we design a novel deep learning architecture, so-called DeepFrag-k, which identifies fold discriminative features at fragment level to improve the accuracy of protein fold recognition. DeepFrag-k is composed of two stages: the first stage employs a multi-modal Deep Belief Network (DBN) to predict the potential structural fragments given a sequence, represented as a fragment vector, and then the second stage uses a deep convolutional neural network (CNN) to classify the fragment vector into the corresponding fold.

Results: Our results show that DeepFrag-k yields …