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Articles 31 - 60 of 1036

Full-Text Articles in Physical Sciences and Mathematics

A Performance Comparison Of Machine Learning Algorithms For Arced Labyrinth Spillways, Fernando Salazar, Brian M. Crookston Mar 2019

A Performance Comparison Of Machine Learning Algorithms For Arced Labyrinth Spillways, Fernando Salazar, Brian M. Crookston

Publications

Labyrinth weirs provide an economic option for flow control structures in a variety of applications, including as spillways at dams. The cycles of labyrinth weirs are typically placed in a linear configuration. However, numerous projects place labyrinth cycles along an arc to take advantage of reservoir conditions and dam alignment, and to reduce construction costs such as narrowing the spillway chute. Practitioners must optimize more than 10 geometric variables when developing a head–discharge relationship. This is typically done using the following tools: empirical relationships, numerical modeling, and physical modeling. This study applied a new tool, machine learning, to the ...


Long Reach Lane At Long Marsh, Harpswell, 2018 Post-Project Monitoring Report; Year 5 Of 5, Matthew Craig Mar 2019

Long Reach Lane At Long Marsh, Harpswell, 2018 Post-Project Monitoring Report; Year 5 Of 5, Matthew Craig

Publications

No abstract provided.


Book Review: Exoplanets : Hidden Worlds And The Quest For Extraterrestrial Life, T. D. Oswalt Mar 2019

Book Review: Exoplanets : Hidden Worlds And The Quest For Extraterrestrial Life, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Exoplanets : Hidden Worlds and the Quest for Extraterrestrial Life. Harvard, 2018. 254p bibl index, 9780674976900 $24.95, 9780674988897


Relaxation-Based Coarsening For Multilevel Hypergraph Partitioning, Ruslan Shaydulin, Jie Chen, Ilya Safro Feb 2019

Relaxation-Based Coarsening For Multilevel Hypergraph Partitioning, Ruslan Shaydulin, Jie Chen, Ilya Safro

Publications

Multilevel partitioning methods that are inspired by principles of multiscaling are the most powerful practical hypergraph partitioning solvers. Hypergraph partitioning has many applications in disciplines ranging from scientific computing to data science. In this paper we introduce the concept of algebraic distance on hypergraphs and demonstrate its use as an algorithmic component in the coarsening stage of multilevel hypergraph partitioning solvers. The algebraic distance is a vertex distance measure that extends hyperedge weights for capturing the local connectivity of vertices which is critical for hypergraph coarsening schemes. The practical effectiveness of the proposed measure and corresponding coarsening scheme is demonstrated ...


An Overview Of Cryptography (Updated Version 24 January 2019), Gary C. Kessler Jan 2019

An Overview Of Cryptography (Updated Version 24 January 2019), Gary C. Kessler

Publications

There are many aspects to security and many applications, ranging from secure commerce and payments to private communications and protecting health care information. One essential aspect for secure communications is that of cryptography. But it is important to note that while cryptography is necessary for secure communications, it is not by itself sufficient. The reader is advised, then, that the topics covered here only describe the first of many steps necessary for better security in any number of situations.


Thermal Structure Of The Mesopause Region During The Wadis-2 Rocket Campaign, Raimund Wörl, Boris Strelnikov, Timo P. Viehl, Josef Höffner, Pierre-Dominique Pautet, Michael J. Taylor, Yucheng Zhao, Franz-Josef Lübken Jan 2019

Thermal Structure Of The Mesopause Region During The Wadis-2 Rocket Campaign, Raimund Wörl, Boris Strelnikov, Timo P. Viehl, Josef Höffner, Pierre-Dominique Pautet, Michael J. Taylor, Yucheng Zhao, Franz-Josef Lübken

Publications

This paper presents simultaneous temperature measurements by three independent instruments during the WADIS-2 rocket campaign in northern Norway (69 N, 14 E) on 5 March 2015. Vertical profiles were measured in situ with the CONE instrument. Continuous mobile IAP Fe lidar (Fe lidar) measurements during a period of 24 h, as well as horizontally resolved temperature maps by the Utah State University (USU) Advanced Mesospheric Temperature Mapper (AMTM) in the mesopause region, are analysed. Vertical and horizontal temperature profiles by all three instruments are in good agreement. A harmonic analysis of the Fe lidar measurements shows the presence of waves ...


Spacetime Groups, Ian M. Anderson, Charles G. Torre Jan 2019

Spacetime Groups, Ian M. Anderson, Charles G. Torre

Publications

A spacetime group is a connected 4-dimensional Lie group G endowed with a left invariant Lorentz metric h and such that the connected component of the isometry group of h is G itself. The Newman-Penrose formalism is used to give an algebraic classification of spacetime groups, that is, we determine a complete list of inequivalent spacetime Lie algebras, which are pairs (g,η), with g being a 4-dimensional Lie algebra and η being a Lorentzian inner product on g. A full analysis of the equivalence problem for spacetime Lie algebras is given which leads to a completely algorithmic solution to ...


Cape Elizabeth Culvert And Habitat Assessment Study, Steve Harding, Jake Aman, Matthew Craig, Robert Malley, Maureen O'Meara Jan 2019

Cape Elizabeth Culvert And Habitat Assessment Study, Steve Harding, Jake Aman, Matthew Craig, Robert Malley, Maureen O'Meara

Publications

Executive Summary:

In early 2017, Jake Aman, representing the Wells National Estuary Research Reserve (WNERR), met with the Cape Elizabeth Public Works Director and Town Planner to talk about culverts. Jake shared aerial photos of culverts located in the Spurwink Marsh where scouring of adjacent habitat areas was evident. He inquired if the town was considering any culvert replacements, in which case WNERR and The Nature Conservancy might be able to partner with the town to promote a habitat sensitive replacement. The outcome of the meeting was a jointly sponsored assessment of major town culverts, including those located in the ...


Network Alignment By Propagating Reliable Similarities, Zirou Qiu, Ruslan Shaydulin, Xiaoyuan Liu, Yuri Alexeev, Christopher S. Henry, Ilya Safro Jan 2019

Network Alignment By Propagating Reliable Similarities, Zirou Qiu, Ruslan Shaydulin, Xiaoyuan Liu, Yuri Alexeev, Christopher S. Henry, Ilya Safro

Publications

Networks model a variety of complex phenomena across different domains. In many applications, one of the central questions is how to align two or more networks to infer the similarities between nodes and discover potential correspondence. In this paper, we propose a network alignment algorithm that relies exclusively on the underlying graph structure. Under the guidance of rules which we defined, we compute the similarity between a pair of cross-network vertices iteratively based on their neighborhood. The resulting cross-network similarity matrix is then used to infer a permutation matrix which encodes the alignment. We improve the performance of a commonly ...


Uas Flight Operations In Complex Terrain: Assessing The Agricultural Impact From Hurricane Maria In The Central Mountainous Region Of Puerto Rico, Kevin A. Adkins Jan 2019

Uas Flight Operations In Complex Terrain: Assessing The Agricultural Impact From Hurricane Maria In The Central Mountainous Region Of Puerto Rico, Kevin A. Adkins

Publications

Hurricane Maria struck Puerto Rico in September 2017 as a Category 4 storm causing major damage to infrastructure, agriculture and natural ecosystems, as well as the loss of many lives. Among the crops hardest hit was coffee, one of the most important crops in Puerto Rico. As a perennial system, coffee takes various production forms along a gradient from high shade/biodiversity coffee farms to low shade coffee monocultures and therefore offers an ideal means for the study of resistance and resilience of an agroecosystem to weather and climate disturbance. During the summer of 2018, 14 impacted farms across the ...


First Mms Observation Of Energetic Particles Trapped In High-Latitude Magnetic Field Depressions, Katariina Nykyri, Christina Chu, Xuanye Ma, Stephen A. Fuselier, Rachel Rice Jan 2019

First Mms Observation Of Energetic Particles Trapped In High-Latitude Magnetic Field Depressions, Katariina Nykyri, Christina Chu, Xuanye Ma, Stephen A. Fuselier, Rachel Rice

Publications

We present a case study of the Magnetospheric Multiscale (MMS) observations of the Southern Hemispheric dayside magnetospheric boundaries under southward interplanetary magnetic field direction with strong By component. During this event MMS encountered several magnetic field depressions characterized by enhanced plasma beta and high fluxes of high‐energy electrons and ions at the dusk sector of the southern cusp region that resemble previous Cluster and Polar observations of cusp diamagnetic cavities. Based on the expected maximum magnetic shear model and magnetohydrodynamic simulations, we show that for the present event the diamagnetic cavity‐like structures were formed in an unusual location ...


Stem And Sustainability: Creating Aviation Professional Change Agents, P. Clark, Doreen Mcgunagle, L. Zizka Jan 2019

Stem And Sustainability: Creating Aviation Professional Change Agents, P. Clark, Doreen Mcgunagle, L. Zizka

Publications

With the evolution of the workforce and the growing needs of the aviation industry, a clear need for concrete sustainability initiatives and actions have emerged. Sustainability in this sense becomes a matter of survival. For this reason, in this chapter, we will attempt to close three gaps in current sustainability studies: Theory vs practice, intention vs behavior, and education vs workplace.

Our purpose is to develop a ‘simple’ strategy for integrating all three pillars of sustainability into STEM HE programs that create authentic engagement and real buy-in from the students that are then replicated in the workplace. Based on the ...


Vortex: A New Rocketexperiment To Studymesoscale Dynamics At The Turbopause, Gerald A. Lehmacher, Jonathan B. Snively, Aroh Barjatya, Miguel F. Larsen, Michael J. Taylor, Franz-Josef Lübken, Jorge L. Chau Jan 2019

Vortex: A New Rocketexperiment To Studymesoscale Dynamics At The Turbopause, Gerald A. Lehmacher, Jonathan B. Snively, Aroh Barjatya, Miguel F. Larsen, Michael J. Taylor, Franz-Josef Lübken, Jorge L. Chau

Publications

The goal of this new investigation is to better understand gravity waves and their interactions as they propagate from the mesosphere into the lower thermosphere, to characterize the mesoscale wind field, and to identify regions of divergence, vorticity, and stratified turbulence. The Vorticity Experiment (VortEx) will comprise two salvoes of each two sounding rockets scheduled to be launched from Andøya Space Center, Norway in February 2022. The rockets will observe horizontally spaced wind profiles, neutral density and temperature profiles, and plasma densities. Additional information about the background conditions and mesoscale dynamics will be obtained by lidars, meteor radars and a ...


Book Review: Life On Mars: What To Know Before We Go, T. D. Oswalt Dec 2018

Book Review: Life On Mars: What To Know Before We Go, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Life on Mars: what to know before we go. Princeton, 2018. 302p index ISBN 9780691180533, $29.95; ISBN 9781400889945 ebook, contact publisher for price.


Bayesian Analysis Of Two Stellar Populations In Galactic Globular Clusters Ii: Ngc 5024, Ngc 5272, And Ngc 6352, Rachel Wagner-Kaiser, Ted Von Hippel, David Stenning, Elliot Robinson, Ata Sarajedini, David Van Dyk, Nathan Stein, William H. Jefferys Nov 2018

Bayesian Analysis Of Two Stellar Populations In Galactic Globular Clusters Ii: Ngc 5024, Ngc 5272, And Ngc 6352, Rachel Wagner-Kaiser, Ted Von Hippel, David Stenning, Elliot Robinson, Ata Sarajedini, David Van Dyk, Nathan Stein, William H. Jefferys

Publications

We use Cycle 21 Hubble Space Telescope (HST) observations and HST archival ACS Treasury observations of Galactic Globular Clusters to find and characterize two stellar populations in NGC 5024 (M53), NGC 5272 (M3), and NGC 6352. For these three clusters, both single and double-population analyses are used to determine a best fit isochrone(s). We employ a sophisticated Bayesian analysis technique to simultaneously fit the cluster parameters (age, distance, absorption, and metallicity) that characterize each cluster. For the two-population analysis, unique population level helium values are also fit to each distinct population of the cluster and the relative proportions of ...


Interaction Between Gravitational Radiation And Electromagnetic Radiation, Preston Jones, Douglas Singleton Nov 2018

Interaction Between Gravitational Radiation And Electromagnetic Radiation, Preston Jones, Douglas Singleton

Publications

In this review paper we investigate the connection between gravity and electromagnetism from Faraday to the present day. The particular focus is on the connection between gravitational and electromagnetic radiation. We discuss electromagnetic radiation produced when a gravitational wave passes through a magnetic field. We then discuss the interaction of electromagnetic radiation with gravitational waves via Feynman diagrams of the process graviton + graviton → photon + photon. Finally we review recent work on the vacuum production of counterpart electromagnetic radiation by gravitational waves.


Testing Velocity-Dependent Cpt-Violating Gravitational Forces With Radio Pulsars, Lijing Shao, Quentin G. Bailey Oct 2018

Testing Velocity-Dependent Cpt-Violating Gravitational Forces With Radio Pulsars, Lijing Shao, Quentin G. Bailey

Publications

In the spirit of effective field theory, the standard-model extension (SME) provides a comprehensive framework to systematically probe the possibility of Lorentz/CPT violation. In the pure gravity sector, operators with mass dimension larger than 4, while in general being advantageous to short-range experiments, are hard to investigate with systems of astronomical size. However, there is exception if the leading-order effects are CPT-violating and velocity-dependent. Here we study the lowest-order operators in the pure gravity sector that violate the CPT symmetry with carefully chosen relativistic binary pulsar systems. Applying the existing analytical results to the dynamics of a binary orbit ...


Gravity's Light In The Shadow Of The Moon, Andri Gretarsson, Preston Jones, Douglas Singleton Oct 2018

Gravity's Light In The Shadow Of The Moon, Andri Gretarsson, Preston Jones, Douglas Singleton

Publications

In this essay we look at the possibility of vacuum production of very low frequency electromagnetic radiation from a gravitational wave background (i.e. gravity's light). We also propose that this counterpart electromagnetic radiation should be detectable by a lunar orbiting satellite which is periodically occulted by the Moon (i.e., in the shadow of the Moon). For concreteness we consider the possibility of detection of both the gravitational wave and hypothesized electromagnetic radiation counterpart from the supernova core collapse of Betelgeuse


Relating Noncommutative So(2,3)* Gravity To The Lorentz-Violating Standard-Model Extension, Quentin G. Bailey, Charles D. Lane Oct 2018

Relating Noncommutative So(2,3)* Gravity To The Lorentz-Violating Standard-Model Extension, Quentin G. Bailey, Charles D. Lane

Publications

We consider a model of noncommutative gravity that is based on a spacetime with broken local SO(2,3)* symmetry. We show that the torsion-free version of this model is contained within the framework of the Lorentz-violating Standard-Model Extension (SME). We analyze in detail the relation between the torsion-free, quadratic limits of the broken SO(2,3)* model and the Standard-Model Extension. As part of the analysis, we construct the relevant geometric quantities to quadratic order in the metric perturbation around a flat background.


Weighted Composition Operators On Analytic Function Spaces: Some Recent Progress, Dip Acharyya Oct 2018

Weighted Composition Operators On Analytic Function Spaces: Some Recent Progress, Dip Acharyya

Publications

Theory of Composition Operators is a steady point of interest for almost 100 years. While studying these operators, our general goal is to describe their operator theoretic properties in terms of the associated function symbols. In this talk, I will discuss some recent results concerning linear combinations (sums, differences, etc.) of weighted composition operators in certain spaces of Analytic functions.


Superresolution Mapping Of Energy Landscape For Single Charge Carriers In Plastic Semiconductors, Yifei Jiang, Jason Mcneill Oct 2018

Superresolution Mapping Of Energy Landscape For Single Charge Carriers In Plastic Semiconductors, Yifei Jiang, Jason Mcneill

Publications

The performance of conjugated polymer devices is largely dictated by charge transport processes. However, it is difficult to obtain a clear relationship between conjugated polymer structures and charge transport properties, due to the complexity of the structure and the dispersive nature of charge transport in conjugated polymers. Here, we develop a method to map the energy landscape for charge transport in conjugated polymers based on simultaneous, correlated charge carrier tracking and single-particle fluorescence spectroscopy. In nanoparticles of the conjugated polymer poly[9,9-dioctylfluorenyl-2,7-diyl)-co-1,4-benzo-{2,1′-3}-thiadiazole)], two dominant chain conformations were observed, a blue-emitting phase ...


A Bayesian Analysis Of The Ages Of Four Open Clusters, Elizabeth Jeffery, Ted Von Hippel, David A. Van Dyk, David C. Stenning, Elliot Robinson, Nathan Sten, William H. Jefferys Oct 2018

A Bayesian Analysis Of The Ages Of Four Open Clusters, Elizabeth Jeffery, Ted Von Hippel, David A. Van Dyk, David C. Stenning, Elliot Robinson, Nathan Sten, William H. Jefferys

Publications

In this paper we apply a Bayesian technique to determine the best fit of stellar evolution models to find the main sequence turn off age and other cluster parameters of four intermediate-age open clusters: NGC 2360, NGC 2477, NGC 2660, and NGC 3960. Our algorithm utilizes a Markov chain Monte Carlo technique to fit these various parameters, objectively finding the best-fit isochrone for each cluster. The result is a high-precision isochrone fit. We compare these results with the those of traditional “by-eye” isochrone fitting methods. By applying this Bayesian technique to NGC 2360, NGC 2477, NGC 2660, and NGC 3960 ...


Weighted Composition Operators On Spaces Of Analytic Functions: A Survey, Soumyadip Acharyya Sep 2018

Weighted Composition Operators On Spaces Of Analytic Functions: A Survey, Soumyadip Acharyya

Publications

“Pure mathematics is, in its way, the poetry of logical ideas.” - Albert Einstein. Pure mathematicians study abstract entities and structures that underlie mathematics. Although their general perspective is “math for math’s sake”, sometimes even the most abstract mathematics can have unexpected applications! Come learn some of these astonishing discoveries in the history of science and mathematics! They might make you thrilled but keep in mind real-world usage is rarely the goal behind developing a new mathematical theory.

Welcome to the world of pure mathematics! In this talk, we will focus on the theory of composition operators which is a ...


Database Review: Sao/Nasa Astrophysics Data System, Laura Pope Robbins Sep 2018

Database Review: Sao/Nasa Astrophysics Data System, Laura Pope Robbins

Publications

Laura Pope Robbins is an advisor for The Charleston Advisor, and the review below is included in Scholarly Commons with the permission of the publisher.

The Astrophysics Data System (ADS) is the premier Open Access research database for astronomy and astrophysics containing over 13 million bibliographic records. These records include journal articles, books, conference proceedings, historical observatory bulletins, and other gray literature. An exceptional feature of ADS is the visualizations it creates, showing author networks, overlapping citations, and frequently occurring terminology giving researchers new ways to explore the literature. It is a unique resource that is as easy for a ...


E-Hooks Provide Guidance And A Soft Landing For The Microtubule Binding Domain Of Dynein, Nayere Tajielyato, Lin Li, Yunhui Peng, Joshua Alper, Emil Alexov Sep 2018

E-Hooks Provide Guidance And A Soft Landing For The Microtubule Binding Domain Of Dynein, Nayere Tajielyato, Lin Li, Yunhui Peng, Joshua Alper, Emil Alexov

Publications

Macromolecular binding is a complex process that involves sensing and approaching the binding partner, adopting the proper orientation, and performing the physical binding. We computationally investigated the role of E-hooks, which are intrinsically disordered regions (IDRs) at the C-terminus of tubulin, on dynein microtubule binding domain (MTBD) binding to the microtubule as a function of the distance between the MTBD and its binding site on the microtubule. Our results demonstrated that the contacts between E-hooks and the MTBD are dynamical; multiple negatively charted patches of amino acids on the E-hooks grab and release the same positively charged patches on the ...


Identifying Weak Interdomain Interactions That Stabilize The Supertertiary Structure Of The N-Terminal Tandem Pdz Domains Of Psd-95, Inna S. Yanez Orozco, Frank A. Mindlin, Junyan Ma, Bo Wang, Brie Levesque, Matheu Spencer, Soheila Rezaei Adariani, George Hamilton, Feng Ding, Mark E. Bowen, Hugo Sanabria Sep 2018

Identifying Weak Interdomain Interactions That Stabilize The Supertertiary Structure Of The N-Terminal Tandem Pdz Domains Of Psd-95, Inna S. Yanez Orozco, Frank A. Mindlin, Junyan Ma, Bo Wang, Brie Levesque, Matheu Spencer, Soheila Rezaei Adariani, George Hamilton, Feng Ding, Mark E. Bowen, Hugo Sanabria

Publications

Previous studies of the N-terminal PDZ tandem from PSD-95 produced divergent models and failed to identify interdomain contacts stabilizing the structure. We used ensemble and single-molecule FRET along with replica-exchange molecular dynamics to fully characterize the energy landscape. Simulations and experiments identified two conformations: an open-like conformation with a small contact interface stabilized by salt bridges, and a closed-like conformation with a larger contact interface stabilized by surface-exposed hydrophobic residues. Both interfaces were confirmed experimentally. Proximity of interdomain contacts to the binding pockets may explain the observed coupling between conformation and binding. The low-energy barrier between conformations allows submillisecond dynamics ...


Dust Production And Depletion In Evolved Planetary Systems, J. Farihi, Ted Von Hippel, Rik Van Lieshout, P.W. Cauley, Erik Dennihy, Et Al. Aug 2018

Dust Production And Depletion In Evolved Planetary Systems, J. Farihi, Ted Von Hippel, Rik Van Lieshout, P.W. Cauley, Erik Dennihy, Et Al.

Publications

The infrared dust emission from the white dwarf GD 56 is found to rise and fall by 20 per cent peak-to-peak over 11.2 yr, and is consistent with ongoing dust production and depletion. It is hypothesized that the dust is produced via collisions associated with an evolving dust disc, temporarily increasing the emitting surface of warm debris, and is subsequently destroyed or assimilated within a few years. The variations are consistent with debris that does not change temperature, indicating that dust is produced and depleted within a fixed range of orbital radii. Gas produced in collisions may rapidly re-condense ...


Full Field Computing For Elastic Pulse Dispersion In Inhomogeneous Bars, A. Berezovski, R. Kolman, M. Berezovski, D. Gabriel, V. Adamek Jul 2018

Full Field Computing For Elastic Pulse Dispersion In Inhomogeneous Bars, A. Berezovski, R. Kolman, M. Berezovski, D. Gabriel, V. Adamek

Publications

In the paper, the finite element method and the finite volume method are used in parallel for the simulation of a pulse propagation in periodically layered composites beyond the validity of homogenization methods. The direct numerical integration of a pulse propagation demonstrates dispersion effects and dynamic stress redistribution in physical space on example of a one-dimensional layered bar. Results of numerical simulations are compared with analytical solution constructed specifically for the considered problem. Analytical solution as well as numerical computations show the strong influence of the composition of constituents on the dispersion of a pulse in a heterogeneous bar and ...


Bayesian Hierarchical Modelling Of Initial-Final Mass Relations Across Star Clusters, Shijing Si, David A. Van Dyk, Ted Von Hippel, Elliot Robinson, Elizabeth Jeffery, David C. Stenning Jul 2018

Bayesian Hierarchical Modelling Of Initial-Final Mass Relations Across Star Clusters, Shijing Si, David A. Van Dyk, Ted Von Hippel, Elliot Robinson, Elizabeth Jeffery, David C. Stenning

Publications

The initial-final mass relation (IFMR) of white dwarfs (WDs) plays an important role in stellar evolution. To derive precise estimates of IFMRs and explore how they may vary among star clusters, we propose a Bayesian hierarchical model that pools photometric data from multiple star clusters. After performing a simulation study to show the benefits of the Bayesian hierarchical model, we apply this model to five star clusters: the Hyades, M67, NGC 188, NGC 2168, and NGC 2477, leading to reasonable and consistent estimates of IFMRs for these clusters. We illustrate how a cluster-specific analysis of NGC 188 using its own ...


Rapid Screening Of Ellagitannins In Natural Sources Via Targeted Reporter Ion Triggered Tandem Mass Spectrometry, Jeremiah J. Bowers, Harsha P. Gunawardena, Anaëlle Cornu, Ashwini S. Narvekar, Antoine Richieu, Denis Deffieux, Stéphane Quideau, Nishanth Tharayil Jul 2018

Rapid Screening Of Ellagitannins In Natural Sources Via Targeted Reporter Ion Triggered Tandem Mass Spectrometry, Jeremiah J. Bowers, Harsha P. Gunawardena, Anaëlle Cornu, Ashwini S. Narvekar, Antoine Richieu, Denis Deffieux, Stéphane Quideau, Nishanth Tharayil

Publications

Complex biomolecules present in their natural sources have been difficult to analyze using traditional analytical approaches. Ultrahigh-performance liquid chromatography (UHPLC-MS/MS) methods have the potential to enhance the discovery of a less well characterized and challenging class of biomolecules in plants, the ellagitannins. We present an approach that allows for the screening of ellagitannins by employing higher energy collision dissociation (HCD) to generate reporter ions for classification and collision-induced dissociation (CID) to generate unique fragmentation spectra for isomeric variants of previously unreported species. Ellagitannin anions efficiently form three characteristic reporter ions after HCD fragmentation that allows for the classification of ...