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2021

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Articles 24811 - 24840 of 27886

Full-Text Articles in Physical Sciences and Mathematics

Modern Quantum Mechanics, Why We Need It, How To Use It?, Vahid Karimipour Jan 2021

Modern Quantum Mechanics, Why We Need It, How To Use It?, Vahid Karimipour

Turkish Journal of Physics

A new field of research centered on quantum science and technology is emerging. This rapidly developing field deals with the study and control of single quantum entities, i.e. atoms, ions, photons, which are no longer isolated but are parts of a larger system. Manipulation of these quantum entities forms the basis of modern quantum technology, from quantum computation to quantum communication and quantum sensing. One, therefore, needs to reconsider the basic concepts of state, evolution, and measurement for these so-called open quantum systems. This is a pedagogical review paper on the rudiments of modern quantum mechanics, which keeps citations to …

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Contrasting The Fuzzball And Wormhole Paradigms For Black Holes, Bin Guo, Marcel Hughes, Samir Mathur, Madhur Mehta Jan 2021

Contrasting The Fuzzball And Wormhole Paradigms For Black Holes, Bin Guo, Marcel Hughes, Samir Mathur, Madhur Mehta

Turkish Journal of Physics

We examine an interesting set of recent proposals describing a `wormhole paradigm' for black holes. These proposals require that in some effective variables, semiclassical low-energy dynamics emerges at the horizon. We prove the `effective small corrections theorem' to show that such an effective horizon behavior is not compatible with the requirement that the black hole radiate like a piece of coal as seen from outside. This theorem thus concretizes the fact that the proposals within the wormhole paradigm require some nonlocality linking the hole and its distant radiation. We try to illustrate various proposals for nonlocality by making simple bit …

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An Improvement Of Current Driving And Electrical Conductivity Properties Incovetics, Mesut Atasoyu, Emi̇n Argun Oral, Mehmet Ertuğrul Jan 2021

An Improvement Of Current Driving And Electrical Conductivity Properties Incovetics, Mesut Atasoyu, Emi̇n Argun Oral, Mehmet Ertuğrul

Turkish Journal of Physics

Compared to pure Cu, Cu lattice retaining carbon atoms, called a covetic material, can have better electrical conductivity. Furthermore, the incorporation of carbon nanostructures into Cu-alloys could improve the mechanical properties of Cu-alloys. In the simulation study, we investigated Joule heating due to applied DC current on molten Cu metal concerning how to improve current density of covetic materials. In addition, we will discuss interfacial effects on covetic-metal electrodes to meet better current driving performance. The covetic composite excited at one electrode (width = 10 nm) has a higher current drive capability as a value of 3.54 $10^{7}$ $A /m^{2}$, …

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A Simulation And Experimental Validation Of Third-Order Coma In Nodal Aberrationtheory With A Cassegrain Telescope, Özgür Karci Jan 2021

A Simulation And Experimental Validation Of Third-Order Coma In Nodal Aberrationtheory With A Cassegrain Telescope, Özgür Karci

Turkish Journal of Physics

This study presents a simulation and experimental validation of third-order coma in Nodal Aberration Theory (NAT) with a custom-designed Cassegrain system. The Cassegrain system uses a piezo-driven flexure tool to align the telescope's secondary mirror with respect to the primary mirror. This alignment mechanism is also used to misalign the telescope's secondary mirror to induce the intentional aberrations. The third-order Fringe Zernike coma (Z$_{7/8}$) was simulated utilizing the Cassegrain telescope's real ray-trace model (e.g., in Code V) and analyzed for both the telescope's nominal aligned and misaligned states. The simulated aberration of third-order coma was induced utilizing the secondary mirror …

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Mixing Angles Between The Tetraquark States With Two Heavy Quarks Within Qcdsum Rules, Selçuk Bi̇lmi̇ş Jan 2021

Mixing Angles Between The Tetraquark States With Two Heavy Quarks Within Qcdsum Rules, Selçuk Bi̇lmi̇ş

Turkish Journal of Physics

LHCb collaboration has recently announced the observation of a doubly charmed tetraquark $T_{cc \bar{u} \bar{d}}^+$ state with spin parity $J^P = 1^+$. This exotic state can be explained as a molecular state with small binding energy. According to conventional quark model, both $D^+ D^{0\ast}$ and $(D^0 D^{+\ast})$ multiquark states are expected to have the same mass and flavor in the exact $SU(3)$ symmetry. However, since the quark masses are different, $SU(3) (SU(2))$ symmetry is violated; hence, the mass and flavor eigenstates do not coincide. The mass eigenstates can be represented as a linear combination of the flavor eigenstates, which is …

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Bound States And Energy Eigenvalues Of A Radial Screened Coulomb Potential, Eric Stachura, N. Hancock Jan 2021

Bound States And Energy Eigenvalues Of A Radial Screened Coulomb Potential, Eric Stachura, N. Hancock

Faculty Articles

We analyze bound states and other properties of solutions of a radial Schrödinger equation with a new screened Coulomb potential. In particular, we employ hypervirial relations to obtain eigen-energies for a Hydrogen atom with this potential. Additionally, we appeal to a sharp estimate for a modified Bessel function to estimate the ground state energy of such a system. Finally, when the angular quantum number ℓ ≠ 0, we obtain evidence for a critical screening parameter, above which bound states cease to exist.

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Age And Paleoenvironmental Significance Of The Frazer Beach Member—A New Lithostratigraphic Unit Overlying The End-Permian Extinction Horizon In The Sydney Basin, Australia, Stephen Mcloughlin, Robert S. Nicoll, James L. Crowley, Vivi Vajda, Chris Mays, Christopher R. Fielding, Tracy D. Frank, Alexander Wheeler, Malcolm Bocking Jan 2021

Age And Paleoenvironmental Significance Of The Frazer Beach Member—A New Lithostratigraphic Unit Overlying The End-Permian Extinction Horizon In The Sydney Basin, Australia, Stephen Mcloughlin, Robert S. Nicoll, James L. Crowley, Vivi Vajda, Chris Mays, Christopher R. Fielding, Tracy D. Frank, Alexander Wheeler, Malcolm Bocking

Department of Earth and Atmospheric Sciences: Faculty Publications

The newly defined Frazer Beach Member of the Moon Island Beach Formation is identified widely across the Sydney Basin in both outcrop and exploration wells. This thin unit was deposited immediately after extinction of the Glossopteris flora (defining the terrestrial end- Permian extinction event). The unit rests conformably on the uppermost Permian coal seam in most places. A distinctive granule-microbreccia bed is locally represented at the base of the member. The unit otherwise consists of dark gray to black siltstone, shale, mudstone and, locally, thin lenses of fine-grained sandstone and tuff. The member represents the topmost unit of the Newcastle …

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Opening Of The Gulf Of Mexico: What We Know, What Questions Remain, And How We Might Answer Them, Irina Filina, James Austin, Tony Doré, Elizabeth Johnson, Daniel Minguez, Ian Norton, John Snedden, Robert J. Stern Jan 2021

Opening Of The Gulf Of Mexico: What We Know, What Questions Remain, And How We Might Answer Them, Irina Filina, James Austin, Tony Doré, Elizabeth Johnson, Daniel Minguez, Ian Norton, John Snedden, Robert J. Stern

Department of Earth and Atmospheric Sciences: Faculty Publications

The Gulf of Mexico is an economically important basin with more than a century-long history of hydrocarbon exploration. However, the opening history of the basin remains debated for two reasons: 1) the quality of data does not allow for reliable interpretations of crustal features beneath thick and complex overburden, and 2) most industry well and geophysical data are proprietary. The last concerted effort by industry and academia to summarize the state of knowledge regarding the Gulf of Mexico’s formation was three decades ago and resulted in publication of a major volume as part of the Decade of North American Geology …

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The Rise And Fall Of Wiñaymarka: Rethinking Cultural And Environmental Interactions In The Southern Basin Of Lake Titicaca, Maria C. Bruno, José M. Capriles, Christine A. Hastorf, Sherilyn C. Fritz, D. Marie Weide, Alejandra I. Domic, Paul A. Baker Jan 2021

The Rise And Fall Of Wiñaymarka: Rethinking Cultural And Environmental Interactions In The Southern Basin Of Lake Titicaca, Maria C. Bruno, José M. Capriles, Christine A. Hastorf, Sherilyn C. Fritz, D. Marie Weide, Alejandra I. Domic, Paul A. Baker

Department of Earth and Atmospheric Sciences: Faculty Publications

Investigations of how past human societies managed during times of major climate change can inform our understanding of potential human responses to ongoing environmental change. In this study, we evaluate the impact of environmental variation on human communities over the last four millennia in the southern Lake Titicaca basin of the Andes, known as Lake Wiñaymarka. Refined paleoenvironmental reconstructions from new diatom-based reconstructions of lake level together with archaeological evidence of animal and plant resource use from sites on the Taraco Peninsula, Bolivia, reveal frequent climate and lake-level changes within major cultural phases. We posit that climate fluctuations alone do …

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Design And Optimization Of Superconducting Radio-Frequency Electron Sources, Osama Mohsen Jan 2021

Design And Optimization Of Superconducting Radio-Frequency Electron Sources, Osama Mohsen

Graduate Research Theses & Dissertations

High brightness electron beams are an essential component that drives current and future accelerators and accelerator-based light sources including Free-Electron lasers (FELs), electron cooling experiments, and compact ultrafast electron probe setups (e.g. ultrafast electron diffraction). In FEL, the possible use of a superconducting radiofrequency (SRF) electron gun to support the generation of high-repetition-rate bright-beam can produce copious amounts of radiation over a broad range of the electromagnetic spectrum which can be used in several scientific experiments while in electron probes, the use of SRF gun can enable the generation of high brightness electron beams at high repetition rates, e.g., necessary …

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Fly On The Wall: Comparing Arthropod Communities Between Islands With And Without House Mice (Mus Musculus), Wieteke A. Holthuijzen Jan 2021

Fly On The Wall: Comparing Arthropod Communities Between Islands With And Without House Mice (Mus Musculus), Wieteke A. Holthuijzen

Graduate Research Theses & Dissertations

Invertebrates are key to island ecosystems but impacts from invasive mammalian predators are not well documented or understood. Given this knowledge gap, we studied terrestrial arthropod communities in the presence of a common invasive rodent (house mice, Mus musculus) on a subtropical atoll—Midway Atoll National Wildlife Refuge (MANWR). Here, invasive mice recently began to attack and depredate nesting seabirds, prompting a mouse eradication. Although eradication planning efforts are underway, uncertainty remains regarding the ecosystem’s response to mouse removal. As part of a pre-eradication investigation, we conducted a baseline survey of MANWR’s arthropod community structure and diversity, comparing islands with and …

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Frequentist Methods In Handling Misrepresentation Risk, Rexford Mawunyegah Akakpo Jan 2021

Frequentist Methods In Handling Misrepresentation Risk, Rexford Mawunyegah Akakpo

Graduate Research Theses & Dissertations

A commonly encountered risk in insurance business is misrepresentation risk. Misrepresentation is a type of insurance fraud where a policyholder or a policy applicant falsifies his or her risk status in order to pay cheaper premiums for more expensive future risks. It is difficult and expensive for insurance companies to detect this kind of risk. With high cost of sophisticated underwriting, it becomes a norm for insurance companies to regularly rely on the policy applicant to self-report most of their risk statuses. We employ a frequentist approach by using expectation-maximization (EM) algorithm to carry out maximum likelihood estimation of the …

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Induction And Prevention Of Electron Transport In Langmuir-Blodgett Films Of 3d-Based Metallosurfactants: Studies On Current Rectification And Corrosion Inhibition, Aldora Devale Kapuralalage Isuri Weeraratne Jan 2021

Induction And Prevention Of Electron Transport In Langmuir-Blodgett Films Of 3d-Based Metallosurfactants: Studies On Current Rectification And Corrosion Inhibition, Aldora Devale Kapuralalage Isuri Weeraratne

Wayne State University Dissertations

The work reported in this thesis focused on the use of redox-active metallosurfactants for current rectification and redox-innocent metallosurfactants for corrosion inhibition. These studies were done based on the hypothesis that redox-active metallosurfactnats can promote electron transport, while redox-innocent metallosurfactants can hinder electron transport. As such, new redox-active phenolate based iron(III), chromium(III), oxovanadium(IV) and redox-innocent gallium(III) and zinc(II) complexes were synthesized and characterized for the aforementioned applications. First, we studied the current rectification ability of a homobimetallic iron(III) hydrophobe with [N4O6] ligand environment. This complex displayed rectification with rectification ratio ranges from 2.6 to 9.8 between -2.0 and 2.0 V …

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Reversible Addition-Fragmentation Chain-Transfer Emulsion Polymerization And Its Application To Waterborne Coatings, Andrew Balgeman Jan 2021

Reversible Addition-Fragmentation Chain-Transfer Emulsion Polymerization And Its Application To Waterborne Coatings, Andrew Balgeman

Graduate Research Theses & Dissertations

Waterborne acrylic latex makes up a vast majority of the architectural coatings market, including most of the paints sold in retail stores. Most, if not all, of these latex formulations are prepared using radical polymerization of acrylic monomers. Reversible addition-fragmentation chain-transfer (RAFT) polymerization has been researched for over two decades, but to this point has made very little progress finding success in commercial applications. Indeed, a majority of RAFT research has been dedicated to successfully polymerizing different monomers with good degree of polymerization control, and very little research has been directed toward actual coating applications. In this study, we focused …

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Pharmaceuticals In The Environment: Health Implications And Environmental Toxicity, Jessica Phillips Jan 2021

Pharmaceuticals In The Environment: Health Implications And Environmental Toxicity, Jessica Phillips

Wayne State University Dissertations

Approximately 2.9 billion prescriptions are written annually in the United States, with a multitude of biochemical actions, with 63151 tons used by food producing animals worldwide and an additional 55-77 million prescriptions written for companion animals. With increasing prescription and unknown toxicologic effects of many of these chemicals, zebrafish (danio rerio), an NIH approved human model, were used to model potentially health effects. Significant abnormalities were seen with extended duration metformin exposure from 4 hours post fertilization up to 5 days post fertilization, although short term metformin exposure for 24 hours at 4-5 days post fertilization did not lead to …

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Addressing The Ecological Fallacy With Lagrangian Inference, Michael Schwob Jan 2021

Addressing The Ecological Fallacy With Lagrangian Inference, Michael Schwob

Calvert Undergraduate Research Awards

Most epidemiologists elect to use statistical models that use population-level data to make inference on the spread of some virus or disease. This has become commonplace in the fields of epidemiology and biostatistics since most data used to construct and verify epidemic models are recorded at the population-level. Obtaining inference from a population-level model may be beneficial in studying the spread of disease in a homogeneous population, but the use of such models to describe a heterogeneous population results in inadequate inference. The inaccuracy of these models is further amplified when one tries to make individual-level inference from these population-level …

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Awareness Of Blockchain Usage, Structure, & Generation Of Platform’S Energy Consumption: Working Towards A Greener Blockchain, Loreen Marie Powell, Michalina Hendon, Andrew Mangle, Hayden Wimmer Jan 2021

Awareness Of Blockchain Usage, Structure, & Generation Of Platform’S Energy Consumption: Working Towards A Greener Blockchain, Loreen Marie Powell, Michalina Hendon, Andrew Mangle, Hayden Wimmer

Department of Information Technology Faculty Publications

Blockchain is a disruptive information technology innovation with energy consumption. As more organizations look to implement or embrace blockchain innovations, research must focus on making the blockchain greener. This research explores the current innovative blockchain usage, structure, generations, and energy consumption. An energy consumption comparison for consensus protocols is provided along with a list of recommendations for implementing green blockchains. This paper provides a significant impact upon previous literature and aids organizations considering implementing a green blockchain.

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Implementing Connectivity Conservation In Canada, Christopher J. Lemieux, Aerin L. Jacob, Paul A. Gray Jan 2021

Implementing Connectivity Conservation In Canada, Christopher J. Lemieux, Aerin L. Jacob, Paul A. Gray

Geography and Environmental Studies Faculty Publications

No abstract provided.

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Extreme Heterogeneity In Mid-Ocean Ridge Mantle Revealed In Lavas From The 8°20′N Near-Axis Seamount Chain, Molly Anderson, V. Dorsey Wanless, Michael Perfit, Ethan Conrad, Patricia Gregg, Daniel Fornari, W. Ian Ridley Jan 2021

Extreme Heterogeneity In Mid-Ocean Ridge Mantle Revealed In Lavas From The 8°20′N Near-Axis Seamount Chain, Molly Anderson, V. Dorsey Wanless, Michael Perfit, Ethan Conrad, Patricia Gregg, Daniel Fornari, W. Ian Ridley

Geosciences Faculty Publications and Presentations

Lavas that have erupted at near‐axis seamounts provide windows into mid‐ocean ridge mantle heterogeneity and melting systematics which are not easily observed on‐axis at fast‐spreading centers. Beneath ridges, most heterogeneity is obscured as magmas aggregate toward the ridge, where they efficiently mix and homogenize during transit and within shallow magma chambers prior to eruption. To understand the deeper magmatic processes contributing to oceanic crustal formation, we examine the compositions of lavas erupted along a chain of near‐axis seamounts and volcanic ridges perpendicular to the East Pacific Rise. We assess the chemistry of near‐ridge mantle using a ∼200 km‐long chain at …

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The Role Of Culture In Land System Science, Kelly Hopping Jan 2021

The Role Of Culture In Land System Science, Kelly Hopping

Human-Environment Systems Research Center Faculty Publications and Presentations

Land system science (LSS) has substantially advanced understanding of land dynamics throughout the world. However, studies that explicitly address the causative role of culture in land systems have been fairly limited relative to those examining other structural dimensions (e.g. markets, policies, climate). In this paper, we aim to start a discussion on how to better include culture in LSS. Through four examples, we show how aspects of culture influence land systems in myriad ways. Building on existing causal land system models, we propose a conceptual framework for the role of culture in land use and summarize promising methodological innovations for …

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1,4,5,8-Naphthalene Tetracarboxylate Dianhydride/G-C3N4 Van Der Waals Heterojunctions Exhibit Enhanced Photochemical H2O2 Production And Antimicrobial Activity, John H. Thurston, Molly Vitale-Sullivan, Azhar Koshkimbayeva, Tyler R. Smith, Kenneth A. Cornell Jan 2021

1,4,5,8-Naphthalene Tetracarboxylate Dianhydride/G-C3N4 Van Der Waals Heterojunctions Exhibit Enhanced Photochemical H2O2 Production And Antimicrobial Activity, John H. Thurston, Molly Vitale-Sullivan, Azhar Koshkimbayeva, Tyler R. Smith, Kenneth A. Cornell

Chemistry and Biochemistry Faculty Publications and Presentations

Organic semiconductors, including graphitic carbon nitride (g-C3N4, CN), represent an important class of materials for the development of novel antimicrobial or biomedical technologies. Of principal interest is the ability of these materials to catalyze the reduction of elemental oxygen to generate reactive oxygen species (ROS), including hydrogen peroxide (H2O2). Here, we describe the fabrication of photoactive van der Waals heterojunctions incorporating 1,4,5,8-naphthalene tetracarboxylic dianhydride (NTCDA) and CN. The composite heterojunction systems were characterized by a combination of physical (TEM, SEM, pXRD), spectroscopic (FT-IR, XPS, DRUV, photoluminescence, TCSPC) and kinetic experiments. Electronic interactions …

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

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

VIMS Articles

Nature-based shoreline protection provides a welcome class of adaptations to promote ecological resilience in the face of climate change. Along coastlines, living shorelines are among the preferred adaptation strategies to both reduce erosion and provide ecological functions. As an alternative to shoreline armoring, living shorelines are viewed favorably among coastal managers and some private property owners, but they have yet to undergo a thorough examination of how their levels of ecosystem functions compare to their closest natural counterpart: fringing marshes. Here, we provide a synthesis of results from a multi-year, large-spatial-scale study in which we compared numerous ecological metrics (including …

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The Effect Of Coastal Landform Development On Decadal-To Millennial-Scale Longshore Sediment Fluxes: Evidence From The Holocene Evolution Of The Central Mid-Atlantic Coast, Usa, Justin L. Shawler, Christopher J. Hein, Chloe A. Obara, Mahina G. Robbins, Sebastien Huot, Michael S. Fenster Jan 2021

The Effect Of Coastal Landform Development On Decadal-To Millennial-Scale Longshore Sediment Fluxes: Evidence From The Holocene Evolution Of The Central Mid-Atlantic Coast, Usa, Justin L. Shawler, Christopher J. Hein, Chloe A. Obara, Mahina G. Robbins, Sebastien Huot, Michael S. Fenster

VIMS Articles

The behavior of siliciclastic coastal systems is largely controlled by the interplay between accommodation creation and infilling. Factors responsible for altering sediment fluxes to and along open-ocean coasts include cross-shore mobilization of sediment primarily from tidal currents and storms as well as changes in alongshore transport rates moderated by changing wave conditions, river sediment inputs, artificial shoreline hardening and modification, and natural sediment trapping in updrift coastal landforms. This paper focuses on the latter relationships. To address understudied interactions between updrift coastal landforms and downdrift coastal behavior, we quantify the volume and fluxes of sediment trapped in the Assateague-Chincoteague-Wallops barrier-island …

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Astronomical Tide And Storm Surge Signals Observed In An Isolated Inland Maar Lake Near The Coast, M. Li, C. Li, L. Xie, Wei Huang, Q. Zheng, K. Tan, Y. Hong Jan 2021

Astronomical Tide And Storm Surge Signals Observed In An Isolated Inland Maar Lake Near The Coast, M. Li, C. Li, L. Xie, Wei Huang, Q. Zheng, K. Tan, Y. Hong

VIMS Articles

Aimed at the explanation of clear tidal signal and storm surge signals in a closed inland lake near the coast (the Huguangyan Lake), this work uses a combined approach with observations and model experiments. Huguangyan Lake is a closed inland freshwater coneless volcanic crater lake near the coast in tropical southern China, less than 5 km from an estuary. It has a diameter of about 1.5 km and relatively deep water of up to 20 m. Bottom pressure was measured from an acoustic Doppler current profiler (ADCP) for 10 days in September 2018 and 10 days in January 2019. The …

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Advancing Estuarine Ecological Forecasts: Seasonal Hypoxia In Chesapeake Bay, Donald Scavia, Isabella Bertani, (...), Marjorie A.M. Friedrichs, Et Al Jan 2021

Advancing Estuarine Ecological Forecasts: Seasonal Hypoxia In Chesapeake Bay, Donald Scavia, Isabella Bertani, (...), Marjorie A.M. Friedrichs, Et Al

VIMS Articles

Ecological forecasts are quantitative tools that can guide ecosystem management. The coemergence of extensive environmental monitoring and quantitative frameworks allows for widespread development and continued improvement of ecological forecasting systems. We use a relatively simple estuarine hypoxia model to demonstrate advances in addressing some of the most critical challenges and opportunities of contemporary ecological forecasting, including predictive accuracy, uncertainty characterization, and management relevance. We explore the impacts of different combinations of forecast metrics, drivers, and driver time windows on predictive performance. We also incorporate multiple sets of state-variable observations from different sources and separately quantify model prediction error and measurement …

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Molluscan Aminostratigraphy Of The Us Mid-Atlantic Quaternary Coastal System: Implications For Onshore-Offshore Correlation, Paleochannel And Barrier Island Evolution, And Local Late Quaternary Sea-Level History, John F. Wehmiller, Laura L. Brothers, (...), Christopher J. Hein, Justin L. Shawler Jan 2021

Molluscan Aminostratigraphy Of The Us Mid-Atlantic Quaternary Coastal System: Implications For Onshore-Offshore Correlation, Paleochannel And Barrier Island Evolution, And Local Late Quaternary Sea-Level History, John F. Wehmiller, Laura L. Brothers, (...), Christopher J. Hein, Justin L. Shawler

VIMS Articles

The Quaternary record of the US Mid-Atlantic coastal system includes onshore emergent late Pleistocene shoreline deposits, offshore inner shelf and barrier island units, and paleovalleys formed during multiple glacial stage sea-level lowstands. The geochronology of this coastal system is based on uranium series, radiocarbon, amino acid racemization (AAR), and optically stimulated luminescence (OSL) methods. We report over 600 mollusk AAR results from 93 sites between northeastern North Carolina and the central New Jersey shelf, representing samples from both onshore cores or outcrops, sub-barrier and offshore cores, and transported shells from barrier island beaches. AAR age estimates are constrained by paired …

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Coastal Setting Determines Tidal Marsh Sustainability With Accelerating Sea-Level Rise, Karinna Nunez, Yinglong J. Zhang, Donna M. Bilkovic, Carl Hershner Jan 2021

Coastal Setting Determines Tidal Marsh Sustainability With Accelerating Sea-Level Rise, Karinna Nunez, Yinglong J. Zhang, Donna M. Bilkovic, Carl Hershner

VIMS Articles

There is an increasing concern over how accelerated rates of sea-level rise (SLR) will impact tidal marsh ecosystems. The present study evaluates the potential impacts of SLR on marsh sustainability using the Tidal Marsh Model (TMM) with the addition of a new vegetation algorithm within the SCHISM (Semi-implicit Cross-scale Hydroscience Integrated System Model) framework. This new functionality contributes to an improved understanding of how vegetation affects the mean flow velocity and turbulence, and consequently, the sedimentation processes. Using two SLR scenarios (intermediate and extreme SLR rates), we projected the changes in marsh extent over the next 50 years in two …

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Particulate Organic Matter Distributions In The Water Column Of The Chukchi Sea During Late Summer, Miguel A. Goni, Lauren W. Juranek, Rachel E. Sipler, Kylie A. Welch Jan 2021

Particulate Organic Matter Distributions In The Water Column Of The Chukchi Sea During Late Summer, Miguel A. Goni, Lauren W. Juranek, Rachel E. Sipler, Kylie A. Welch

VIMS Articles

We investigated the distribution and composition of particulate organic matter in waters from the northeast Chukchi Sea during two late summer periods (September 2016 and August 2017). During both cruises we measured a variety of properties (salinity, temperature, density, chlorophyll fluorescence and particle beam attenuation). We also collected individual water samples from specific depths and measured the concentrations of suspended particulate matter, particulate organic carbon and nitrogen, chlorophyll-a and pheophytin (a chlorophyll degradation product). These measurements revealed highly stratified conditions throughout the study area, with surface waters exhibiting relatively low particle and biomass concentrations, middepth waters with well-defined subsurface chlorophyll …

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Mechanisms Of Pond Expansion In A Rapidly Submerging Marsh, Joshua Himmelstein, Orencio Duran Vinent, Stijn Temmerman, Matthew L. Kirwan Jan 2021

Mechanisms Of Pond Expansion In A Rapidly Submerging Marsh, Joshua Himmelstein, Orencio Duran Vinent, Stijn Temmerman, Matthew L. Kirwan

VIMS Articles

The development and expansion of ponds within otherwise vegetated coastal marshes is a primary driver of marsh loss throughout the world. Previous studies propose that large ponds expand through a wind wave-driven positive feedback, where pond edge erosion rates increase with pond size, whereas biochemical processes control the formation and expansion of smaller ponds. However, it remains unclear which mechanisms dominate at a given scale, and thus how, and how fast, ponds increase their size. Here, we use historical photographs and field measurements in a rapidly submerging microtidal marsh to quantify pond development and identify the processes involved. We find …

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Seasonal Variations And Driving Factors Of The Eastern Maine Coastal Current, Denghui Li, Zhengui Wang, Huijie Xue, Et Al Jan 2021

Seasonal Variations And Driving Factors Of The Eastern Maine Coastal Current, Denghui Li, Zhengui Wang, Huijie Xue, Et Al

VIMS Articles

To investigate the coastal current in the Gulf of Maine (GoME) and its relation to forcing from outside of the gulf, a high-resolution circulation model was developed and validated. Our model shows that the Eastern Maine Coastal Current (EMCC) possesses two cores, an offshore and a nearshore core that peak in summer and spring, respectively. The two cores can be traced back to outflows from the Bay of Fundy from opposite sides of Grand Manan Island, and both cores are deeper and slightly more onshore in summer and fall in response to tidal mixing, surface thermal stratification and wind. The …

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