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Articles 38941 - 38970 of 302422

Full-Text Articles in Physical Sciences and Mathematics

Fast Statistical Methods For The Global Qcd Analysis Of The Proton Structure, Xiaoxian Jing Dec 2021

Fast Statistical Methods For The Global Qcd Analysis Of The Proton Structure, Xiaoxian Jing

Physics Theses and Dissertations

Parton distribution functions (PDFs) quantify probabilities to find partons (quarks and gluons) in a hadron as a function of the fraction x of the hadron’s momentum carried by the parton at a given energy scale. PDFs play a critical role in precision tests of the Standard Model in Higgs boson production and other electroweak processes at the Large Hadron Collider (LHC), and in searches for physics beyond the Standard Model. PDFs are obtained by the global QCD analysis, which fits theoretical predictions to experimental measurements. PDF fitting and post-analysis are computationally intensive. This dissertation discusses fast statistical methods for the …


Functional Structure Of Biomacromolecules In Plant Biomass Using Solid-State Nmr And Dynamic Nuclear Polarization, Alex Kipchirchir Kirui Dec 2021

Functional Structure Of Biomacromolecules In Plant Biomass Using Solid-State Nmr And Dynamic Nuclear Polarization, Alex Kipchirchir Kirui

LSU Doctoral Dissertations

This dissertation summarizes the recent findings on complex biomacromolecules in cell wall of plants and fungi which perform important roles in cell recognition, structural build up, and energy storage. Because of the technical difficulty in characterizing these biomacromolecules, which are often polymorphic and disordered in structure, the functional structure of these biomacromolecules remains elusive. In this dissertation, I present two solid-state nuclear magnetic resonance (ssNMR) and dynamic nuclear polarization (DNP) studies of carbohydrate-rich biosystems: the energy-rich plant biomass and disease-relevant, pathogenic fungi.

First, we have investigated the secondary cell wall of plant biomass which is a carbohydrate-rich biosystem using solid …


Biodiversity And Spatial Heterogeneity In Semi-Natural Grasslands In A Mountain Area In Slovakia, Masae Shiyomi, N. Gáborèík, H. Koizumi, A. Javorkova, E. Uhliarova, O. Jezikova Dec 2021

Biodiversity And Spatial Heterogeneity In Semi-Natural Grasslands In A Mountain Area In Slovakia, Masae Shiyomi, N. Gáborèík, H. Koizumi, A. Javorkova, E. Uhliarova, O. Jezikova

IGC Proceedings (1993-2023)

The spatial pattern of vegetation in the following 3 semi-natural grasslands in Banska Bystrica, Slovakia, was observed in August, 1998: (1) a grassland sown with improved herbage plants after plowing in 1991, (2) a grassland oversown with improved herbage plants in 1991, and (3) a natural grassland without any treatment at the time of establishment. A new method of measuring vegetation was adopted: in each grassland, 50 quadrats 50 cm × 50 cm, composed of 4 smaller cells 25 cm × 25 cm, were set up, and all the species in each cell were recorded. The sown grassland displayed the …


Optimum Area Of Semi-Natural Grassland To Maintain Maximum Butterfly And Avian Species Richness In Japan, A. Shoji, K. Kohyama, H. Sasaki Dec 2021

Optimum Area Of Semi-Natural Grassland To Maintain Maximum Butterfly And Avian Species Richness In Japan, A. Shoji, K. Kohyama, H. Sasaki

IGC Proceedings (1993-2023)

To evaluate the optimum area of semi-natural grassland to maintain maximum butterfly and avian species richness in Japan, digitalized grid data of butterfly and avian distribution, as well as vegetation distribution, throughout the country were used. After obtaining logistic regression models explaining the probabilities of occurrence of each species with semi-natural grassland area and latitude as variables, the optimum value was calculated. The expected maximum species richness of butterflies in the country was the highest in the case of about 40 square kilometers of semi-natural grassland per 100 square kilometers, though the value varied somewhat with latitude. The expected maximum …


Managing Grassy Woodlands: Balancing Production And Conservation Of Resources, John G. Mcivor, Neil D. Macleod, S. Mcintyre Dec 2021

Managing Grassy Woodlands: Balancing Production And Conservation Of Resources, John G. Mcivor, Neil D. Macleod, S. Mcintyre

IGC Proceedings (1993-2023)

Eastern Australian eucalypt woodlands are important agricultural areas that have been widely modified during two centuries of European-style use. Despite this they contain important natural resources including significant biodiversity. Long term sustainability of production depends on maintaining resources and management must be for both production and conservation. A research program on four properties in south east Queensland showed the properties were in generally good condition although all had some problems, and has highlighted a number of significant costs and barriers to adopting a more balanced approach to production and conservation.


Species Segregation And Functional Groups In The Hill Country Of New Zealand, I. López, I. Valentine, D. Hedderley, M. G. Lambert Dec 2021

Species Segregation And Functional Groups In The Hill Country Of New Zealand, I. López, I. Valentine, D. Hedderley, M. G. Lambert

IGC Proceedings (1993-2023)

In the hill country of New Zealand, the soil-sward relationship on hill microrelief was studied. Three categories of slope or microsites were distinguished: low, medium and high. The hypothesis was that soil variables of neighbouring microsites differ, and because of this, there is a segregation of species or functional groups of species between the microsites. Soil features, botanical composition and total annual yield were measured in the slope categories in two similar paddocks; one of which had received long-term phosphorus fertilisation and a non-fertilised paddock. ANOVA, cluster analysis and canonical variate analysis were performed on the data. Unsaturated hydraulic conductivity, …


Convergence Properties Of Solutions Of A Length-Structured Density-Dependent Model For Fish, Geigh Zollicoffer Dec 2021

Convergence Properties Of Solutions Of A Length-Structured Density-Dependent Model For Fish, Geigh Zollicoffer

Rose-Hulman Undergraduate Mathematics Journal

We numerically study solutions to a length-structured matrix model for fish populations in which the probability that a fish grows into the next length class is a decreasing nonlinear function of the total biomass of the population. We make conjectures about the convergence properties of solutions to this equation, and give numerical simulations which support these conjectures. We also study the distribution of biomass in the different age classes as a function of the total biomass.


The Effects Of Solution Ph, Temperature And Redox Environment On Corrosion And Oxide Formation On Inconel X-750, Mohsen Bahrami Dec 2021

The Effects Of Solution Ph, Temperature And Redox Environment On Corrosion And Oxide Formation On Inconel X-750, Mohsen Bahrami

Electronic Thesis and Dissertation Repository

Nickel-based superalloys have a wide range of applications in different industries due to their exceptional mechanical and corrosion-resistance properties. These alloys are widely employed in the nuclear industry. Inside a nuclear reactor, these alloys are exposed to a continuous flux of gamma-radiation. When exposed to gamma-radiation, water decomposes, resulting in the production of oxidizing and reducing species. These species have a considerable effect on the redox chemistry of the solution, which controls the overall corrosion behaviour of nickel-based superalloys.

Corrosion of metals and alloys involves several elementary steps. A comprehensive understanding of these steps and how they influence each other …


Brown Dwarf Atmospheres At High Cadence And Spectral Resolution: A Speed Limit On Brown Dwarf Rotation And A Spectroscopic Atlas Of A 1050 K Atmosphere, Megan E. Tannock Dec 2021

Brown Dwarf Atmospheres At High Cadence And Spectral Resolution: A Speed Limit On Brown Dwarf Rotation And A Spectroscopic Atlas Of A 1050 K Atmosphere, Megan E. Tannock

Electronic Thesis and Dissertation Repository

Brown dwarfs are sub-stellar objects that form like stars but are not sufficiently massive to sustain hydrogen fusion in their cores. Characterized by cool, molecule-rich atmospheres, brown dwarfs demonstrate great diversity in spectroscopic appearance and share many properties with giant exoplanets. In this thesis I present two investigations: the first is a detailed photometric and spectroscopic study of the three most rapidly rotating brown dwarfs. The second examines a spectrum of a cool brown dwarf at unprecedented spectral resolution and signal-to-noise ratio to study the accuracy of theoretical model photospheres.

Photometric monitoring of brown dwarfs has revealed that periodic variability …


Reaction Of Alkynyl- And Alkenyltrifluoroborates With Propargyldicobalt Cations: Alkynylation, Alkenylation, And Cyclopropanation Product Pathways, Brent St Onge, S. Maryamdokht Taimoory, Jeffrey Battersby, John F. Trant, James R. Green Dec 2021

Reaction Of Alkynyl- And Alkenyltrifluoroborates With Propargyldicobalt Cations: Alkynylation, Alkenylation, And Cyclopropanation Product Pathways, Brent St Onge, S. Maryamdokht Taimoory, Jeffrey Battersby, John F. Trant, James R. Green

Chemistry and Biochemistry Publications

The Lewis acid-mediated Nicholas reactions of propargyl acetate–Co2(CO)6 complexes with a series of potassium alkynyltrifluoroborates and potassium alkenyltrifluoroborates are described. Alkynyltrifluoroborates directly alkynylate the intermediate propargyldicobalt cations. In contrast, alkenyltrifluoroborates proceed through one of the three modes of dominant reactivity: C-2-substituted alkenyltrifluorobrates directly alkenylate, predominantly with the retention of stereochemistry. C-1-substituted alkenyltrifluoroborates alkenylate at C-2. Potassium vinyltrifluoroborate incorporates a cyclopropane at the site propargyl to alkynedicobalt. Computational analysis of these systems explains the differential modes of reactivity of alkenyltrifluoroborates and outlines the probable mechanisms for the formation of each product.


Protocol For Fabricating Electroless Nickel Immersion Gold Strain Sensors On Nitrile Butadiene Rubber Gloves For Wearable Electronics, Sara S. Mechael, Yunyun Wu, Yiting Chen, Tricia Breen Carmichael Dec 2021

Protocol For Fabricating Electroless Nickel Immersion Gold Strain Sensors On Nitrile Butadiene Rubber Gloves For Wearable Electronics, Sara S. Mechael, Yunyun Wu, Yiting Chen, Tricia Breen Carmichael

Chemistry and Biochemistry Publications

This protocol describes the fabrication of patterned conductive gold films on nitrile butadiene rubber (NBR) gloves for wearable strain sensors using electroless nickel immersion gold (ENIG) plating, a solution-based metallization technique. The resulting NBR/ENIG films are strain sensitive; resistance measurements of a patterned sensing array can be used to map human hand motions. This protocol also describes challenges related to the ENIG process and troubleshooting steps to achieve conformal gold films for strain sensing over a large working range. For complete details on the use and execution of this protocol, please refer to Mechael et al. (2021).


Computational Thinking For Teachers, Susan Imberman Dec 2021

Computational Thinking For Teachers, Susan Imberman

Open Educational Resources

This is a syllabus for a course in computational thinking. The course described introduces preservice and inservice teachers to the fundamental concepts of computer science, including web design, coding, ethics, computational thinking, course resources, etc.


A Literature Review Of Wetland Treatment Systems Used To Treat Runoff Mixtures Containing Antibiotics And Pesticides From Urban And Agricultural Landscapes, Emily R. Nottingham, Tiffany L. Messer Dec 2021

A Literature Review Of Wetland Treatment Systems Used To Treat Runoff Mixtures Containing Antibiotics And Pesticides From Urban And Agricultural Landscapes, Emily R. Nottingham, Tiffany L. Messer

Biosystems and Agricultural Engineering Faculty Publications

Wetland treatment systems are used extensively across the world to mitigate surface runoff. While wetland treatment for nitrogen mitigation has been comprehensively reviewed, the implications of common-use pesticides and antibiotics on nitrogen reduction remain relatively unreviewed. Therefore, this review seeks to comprehensively assess the removal of commonly used pesticides and antibiotics and their implications for nitrogen removal in wetland treatment systems receiving non-point source runoff from urban and agricultural landscapes. A total of 181 primary studies were identified spanning 37 countries. Most of the reviewed publications studied pesticides (n = 153) entering wetlands systems, while antibiotics (n = 29) had …


Epa Region 8 Qa Document Review Crosswalk, Nikia Greene Dec 2021

Epa Region 8 Qa Document Review Crosswalk, Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Unbuilding: How Deconstruction Is Saving The Planet By Giving Building Materials A Second Life, Diana M. Ducroz Dec 2021

Unbuilding: How Deconstruction Is Saving The Planet By Giving Building Materials A Second Life, Diana M. Ducroz

Capstones

In 2018, more than 600 million tons of construction and demolition (C&D) waste was generated in the United States, more than twice the volume of ordinary trash created by American households and businesses. Even though 80-95% of this concrete, asphalt, steel, wood, drywall, glass and brick can be reused, repurposed or recycled, a quarter of it – or 145 million tons in 2018 – ends up in landfills. Thirty million tons of wood alone – often sturdy, irreplaceable old-growth lumber – is being trashed every year.

Now, a budding ‘build reuse’ movement, made up of environmentalists, architects, historic preservationists, city …


Physics-Informed Machine Learning To Predict Extreme Weather Events, Rthvik Raviprakash, Jonathan Buchanan, Mahdi Bu Ali Dec 2021

Physics-Informed Machine Learning To Predict Extreme Weather Events, Rthvik Raviprakash, Jonathan Buchanan, Mahdi Bu Ali

Discovery Undergraduate Interdisciplinary Research Internship

Extreme weather events refer to unexpected, severe, or unseasonal weather events, which are dynamically related to specific large-scale atmospheric patterns. These extreme weather events have a significant impact on human society and also natural ecosystems. For example, natural disasters due to extreme weather events caused more than $90 billion global direct losses in 2015. These extreme weather events are challenging to predict due to the chaotic nature of the atmosphere and are highly correlated with the occurrence of atmospheric blocking. A key aspect for preparedness and response to extreme climate events is accurate medium-range forecasting of atmospheric blocking events.

Unlike …


Task Classification During Visual Search Using Classic Machine Learning And Deep Learning, Devangi Vilas Chinchankar Dec 2021

Task Classification During Visual Search Using Classic Machine Learning And Deep Learning, Devangi Vilas Chinchankar

Master's Projects

In an average human life, the eyes not only passively scan visual scenes, but most times end up actively performing tasks including, but not limited to, searching, comparing, and counting. As a result of the advances in technology, we are observing a boost in the average screen time. Humans are now looking at an increasing number of screens and in turn images and videos. Understanding what scene a user is looking at and what type of visual task is being performed can be useful in developing intelligent user interfaces, and in virtual reality and augmented reality devices. In this research, …


Approximate Likelihood Based Estimations For Joint Models With Intractable Likelihoods, Karl Stessy M. Bisselou Dec 2021

Approximate Likelihood Based Estimations For Joint Models With Intractable Likelihoods, Karl Stessy M. Bisselou

Theses & Dissertations

This dissertation focuses on the development of approximation approaches for the joint modeling (JM) of repeated measures data and time-to-event data in the presence of analytically or numerically intractable likelihoods. Current likelihood-based inferences for JMs show several limitations including (i) intractability of integrals during marginal likelihood derivations due to the complexity in computations, and (ii) the large number of nuisance parameters (unobserved) posing a problem with convergence. The h-likelihood (HL) and synthetic likelihood (SL) are two computationally efficient estimation approaches that overcome these challenges.

In the presence of extremely high censoring rates, the HL can produce bias parameter estimates. We …


New Age Findings With Microfossils Of The Van Formation (Van, Eastern Anatolia), Ayşegül Güney, Elvan Demi̇rci̇, Kemal Korkmaz, Sefer Örçen Dec 2021

New Age Findings With Microfossils Of The Van Formation (Van, Eastern Anatolia), Ayşegül Güney, Elvan Demi̇rci̇, Kemal Korkmaz, Sefer Örçen

Bulletin of the Mineral Research and Exploration

Van Formation, which is mainly represented by conglomerate, sandstone, marl and limestone, covers a large area around the Van province. The age of the unit was assigned in different localities of the region as late Oligocene - middle Miocene, early Miocene, Burdigalian - Langhian (early - middle Miocene) by previous studies. In order to determine the age of the upper levels of the formation in the east and southeast of Lake Van, a total of 98 samples collected from three measured stratigraphic sections. These samples have been examined in terms of calcareous nannoplankton and planktonic foraminiferal content. 33 species of …


Design And Synthesis Of Small Molecular Probes For Cns And Kidney Disorders, Swagat H. Sharma Dec 2021

Design And Synthesis Of Small Molecular Probes For Cns And Kidney Disorders, Swagat H. Sharma

Theses & Dissertations

The G protein regulated inwardly rectifying potassium channels (GIRK) are a family of inwardly rectifying potassium channels and are key effectors in signaling pathways. GIRK 1/2 channel subunit, predominantly found in the brain, is involved pathophysiology of various neurological disorders including, but not limited to, epilepsy, anxiety, Parkinson's, pain, reward, and addiction. Previously, our laboratory had identified a series of urea containing molecules as GIRK1/2 preferring activators. Unfortunately, the urea series suffers from significant PK liabilities (solubility, brain penetration and high clearance). The chapter 1 of the dissertation describes our efforts in developing three new series of activators with improved …


Comparing The Efficiency Of A Marsh-Sill And Oyster Reef Balls In Attenuating Waves, Navid Tahvildari, Alexa Leone Dec 2021

Comparing The Efficiency Of A Marsh-Sill And Oyster Reef Balls In Attenuating Waves, Navid Tahvildari, Alexa Leone

December 17, 2021: Natural and Nature-Based Solutions (Part 2)

No abstract provided.


Carbon Sequestration Benefits Of Coastal Restoration, Brendan Player Dec 2021

Carbon Sequestration Benefits Of Coastal Restoration, Brendan Player

December 17, 2021: Natural and Nature-Based Solutions (Part 2)

No abstract provided.


Agenda- Hampton Roads Sea Level Rise/Flooding Adaptation Forum, Ben Mcfarlane, Wie Yusuf Dec 2021

Agenda- Hampton Roads Sea Level Rise/Flooding Adaptation Forum, Ben Mcfarlane, Wie Yusuf

December 17, 2021: Natural and Nature-Based Solutions (Part 2)

Agenda for the Hampton Roads Sea Level Rise/Flooding Adaptation Forum on December 17, 2021 via Virtual Forum.

  • Opening Remarks and Introductions: Ben McFarlane, Hampton Roads Planning District Commission and Dr. Wie Yusuf, Old Dominion University and Virginia Sea Grant
  • Navid Tahvildari, of Old Dominion University: Comparing the Efficiency of a Marsh-Sill and Oyster Reef Balls in Attenuating Waves
  • Brendan Player, of Stantec: Carbon Sequestration Benefits of Coastal Restoration
  • Robert Isdell, of Virginia Institute of Marine Science: Living Shorelines Achieve Functional Equivalence to Natural Fringe Marshes Across Multiple Ecological Metrics
  • Closing Remarks and Reminders


Living Shorelines Achieve Functional Equivalence To Natural Fringe Marshes Across Multiple Ecological Metrics, Robert E. Isdell, Donna Marie Bilkovic, Amanda G. Guthrie, Molly M. Mitchell, Randolph M. Chambers, Matthias Leu, Carl Hershner Dec 2021

Living Shorelines Achieve Functional Equivalence To Natural Fringe Marshes Across Multiple Ecological Metrics, Robert E. Isdell, Donna Marie Bilkovic, Amanda G. Guthrie, Molly M. Mitchell, Randolph M. Chambers, Matthias Leu, Carl Hershner

December 17, 2021: Natural and Nature-Based Solutions (Part 2)

No abstract provided.


High Resolution Remote Sensing As A Tool To Improve Coastal Habitat Mapping In The Gulf Of Maine, Gabriel Hesketh Dec 2021

High Resolution Remote Sensing As A Tool To Improve Coastal Habitat Mapping In The Gulf Of Maine, Gabriel Hesketh

Electronic Theses and Dissertations

The derivation of oceanographic and biological parameters from remote sensing is well documented across decades of research. Careful evaluation of satellite products provides insight into the optimal algorithms for image processing, research, and various biogeographical applications. Archived multi-satellite data from the United States Geological Survey offers users decades of continuously updated global data, and the agency has recently updated the Landsat portion of its catalog with Collection 2 files, which offers both Level 1 and Level 2 processed data products. Here, we evaluate the Collection 2 improvements using several published algorithms currently used to derive sea surface temperature, chlorophyll, and …


An Analysis Of Two Photometric Redshift Methods And Their Uses For Finding Void Galaxies, Rochelle J. Steele Dec 2021

An Analysis Of Two Photometric Redshift Methods And Their Uses For Finding Void Galaxies, Rochelle J. Steele

Theses and Dissertations

An extensive survey of extragalactic objects with accurate distances is difficult to perform. Distance at that scale is commonly found with redshift and most easily identified with spectroscopic observations, which are time intensive. This is especially a concern when surveying for the elusive, possibly non-existent dwarf galaxies in the centers of voids, whose light would be so faint that a spectroscopic survey to find them would be unreasonably time consuming. Photometric methods to calculate redshift could provide a much quicker way to find distance, but the photometric methods used thus far are characterized by large errors that make them unusable …


Spin-Dependent Electronic Transport In Noncollinear Antiferromagnetic Antiperovskites, Gautam Gurung Dec 2021

Spin-Dependent Electronic Transport In Noncollinear Antiferromagnetic Antiperovskites, Gautam Gurung

Department of Physics and Astronomy: Dissertations, Theses, and Student Research

Spin-dependent properties are the heart of spintronic devices. Spintronics exploits electron’s spin, in addition to charge, to process and store the information. Recently, antiferromagnetic (AFM) spintronics has emerged as a subfield of spintronics, where an AFM order parameter (the Néel vector) is exploited to control spin-dependent transport properties. Due to being robust against magnetic perturbations, producing no stray fields, and exhibiting ultrafast dynamics, antiferromagnets can serve as promising functional materials for spintronic applications.

Among antiferromagnets, high Néel temperature noncollinear antiperovskites ANMn3 (A = Ga, Ni, Sn, and Pt) are interesting due to their magnetic group symmetry supporting non-trivial spin-dependent …


Request For Change (Rfc) To The Final Butte Reduction Works (Brw) Smelter Area Mine Waste Remediation And Contaminated Groundwater Hydraulic Control Site Phase Iii Quality Assurance Project Plan (Qapp) (Rfc-Brw-2021-03), Josh Bryson Dec 2021

Request For Change (Rfc) To The Final Butte Reduction Works (Brw) Smelter Area Mine Waste Remediation And Contaminated Groundwater Hydraulic Control Site Phase Iii Quality Assurance Project Plan (Qapp) (Rfc-Brw-2021-03), Josh Bryson

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Residential Metals Abatement Program Quality Assurance Project Plan (Non-Residential Parcels - Indoor Dust), Environmental Resource Management (Erm), Elsie King, Christopher Berg, Thomas J. Beckman Dec 2021

Residential Metals Abatement Program Quality Assurance Project Plan (Non-Residential Parcels - Indoor Dust), Environmental Resource Management (Erm), Elsie King, Christopher Berg, Thomas J. Beckman

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Draft Residential Metals Abatement Program Quality Assurance Project Plan (Non-Residential Parcels - Indoor Dust), Elsie King, Christopher Berg, Thomas J. Beckman Dec 2021

Draft Residential Metals Abatement Program Quality Assurance Project Plan (Non-Residential Parcels - Indoor Dust), Elsie King, Christopher Berg, Thomas J. Beckman

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.