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2016-17 Unopa General Meeting Minutes

UNOPA: Minutes

No abstract provided.

Migratory Bird Program At The U.S. Geological Survey Patuxent Wildlife Research Center/U.S. Fish And Wildlife Service Patuxent Research Refuge: Transformations In Management And Research, R. Michael Erwin, Robert Blohm

United States Geological Survey: Publications

The Patuxent Wildlife Research Center (Patuxent), first known as the Patuxent Research Refuge, has a long and rich history of participation in the Department of Interior’s (DOI) cooperative efforts to protect and conserve migratory birds in North America. This chapter describes many of the events and the people involved that constitute this important timeline for international conservation of a shared wildlife resource. The Patuxent Research Refuge, renowned worldwide, is part of the National Wildlife Refuge System of the U.S. Fish and Wildlife Service (USFWS) that has, at different times and under a variety of organizational iterations, provided the physical location …

Urban Sprawl As A Risk Factor In Motor Vehicle Crashes, Reid Ewing, Shima Hamidi, James B. Grace

United States Geological Survey: Staff Publications

A decade ago, compactness/sprawl indices were developed for metropolitan areas and counties which have been widely used in health and other research. In this study, we first update the original county index to 2010, then develop a refined index that accounts for more relevant factors, and finally seek to test the relationship between sprawl and traffic crash rates using structural equation modelling. Controlling for covariates, we find that sprawl is associated with significantly higher direct and indirect effects on fatal crash rates. The direct effect is likely due to the higher traffic speeds in sprawling areas, and the indirect effect …

Polaris: A 30-Meter Probabilistic Soil Series Map Of The Contiguous United States, Nathaniel W. Chaney, Eric F. Wood, Alexander B. Mcbratney, Jonathan W. Hempel, Travis W. Nauman, Colby W. Brungard, Nathan P. Odgers

United States Geological Survey: Staff Publications

A newcomplete map of soil series probabilities has been produced for the contiguous United States at a 30mspatial resolution. This innovative database, named POLARIS, is constructed using available high-resolution geospatial environmental data and a state-of-the-art machine learning algorithm (DSMART-HPC) to remap the Soil Survey Geographic (SSURGO) database. This 9 billion grid cell database is possible using available high performance computing resources. POLARIS provides a spatially continuous, internally consistent, quantitative prediction of soil series. It offers potential solutions to the primary weaknesses in SSURGO: 1) unmapped areas are gap-filled using survey data from the surrounding regions, 2) the artificial discontinuities at …

Paying The Pipers: Mitigating The Impact Of Anticoagulant Rodenticides On Predators And Scavengers, John E. Elliott, Barnett A. Rattner, Richard F. Shore, Nico W. Van Den Brink

United States Geological Survey: Staff Publications

Anticoagulant rodenticides, mainly second-generation forms, or SGARs, dominate the global market for rodent control. Introduced in the 1970s to counter genetic resistance in rodent populations to first-generation compounds such as warfarin, SGARs are extremely toxic and highly effective killers. However, their tendency to persist and accumulate in the body has led to the widespread contamination of terrestrial predators and scavengers. Commercial chemicals that are classified by regulators as persistent, bio-accumulative, and toxic (PBT) chemicals and that are widely used with potential environmental release, such as dichloro-diphenyl-trichloroethane (DDT) or polychlorinated biphenyls (PCBs), have been removed from commerce. However, despite consistently failing …

Chesapeake Bay Fish–Osprey (Pandion Haliaetus) Food Chain: Evaluation Of Contaminant Exposure And Genetic Damage, Rebecca S. Lazarus, Barnett A. Rattner, Peter C. Mcgowan, Robert C. Hale, Natalie K. Karouna-Renier, Richard A. Erickson, Mary Ann Ottinger

United States Geological Survey: Staff Publications

From 2011 to 2013, a large-scale ecotoxicological study was conducted in several Chesapeake Bay (USA) tributaries (Susquehanna River and flats, the Back, Baltimore Harbor/Patapsco Rivers, Anacostia/ middle Potomac, Elizabeth and James Rivers) and Poplar Island as a mid-Bay reference site. Osprey (Pandion haliaetus) diet and the transfer of contaminants from fish to osprey eggs were evaluated. The most bioaccumulative compounds (biomagnification factor>5) included p,p’-dichlorodiphenyldichloroethylene (DDE), total polychlorinated biphenyls (PCBs), total polybrominated diphenyl ethers (PBDEs), and bromodiphenyl ether (BDE) congeners 47, 99, 100, and 154. This analysis suggested that alternative brominated flame retardants and other compounds (methoxytriclosan) are not appreciably …

Immunoglobulin Detection Inwild Birds: Effectiveness Of Three Secondary Anti-Avian Igy Antibodies In Direct Elisas In 41 Avian Species, Carol A. Fassbinder-Orth, Travis E. Wilcoxen, Tiffany Tran, Raoul K. Boughton, Jeanne M. Fair, Erik K. Hofmeister, Jennifer L. Grindstaff, Jen C. Owen

United States Geological Survey: Staff Publications

1.Immunological reagents for wild, non-model species are limited or often non-existent for many species.

2. In this study, we compare the reactivity of a newanti-passerine IgY secondary antibody with existing secondary antibodies developed for use with birds. Samples from 41 species from the following six avian orders were analysed: Anseriformes (1 family, 1 species), Columbiformes (1 family, 2 species), Galliformes (1 family, 1 species), Passeriformes (16 families, 34 species), Piciformes (1 family, 2 species) and Suliformes (1 family, 1 species). Direct ELISAs were performed to detect total IgY using goat anti-passerine IgY, goat anti-chicken IgY or goat anti-bird IgY secondary …

Elevation Dynamics In A Restored Versus A Submerging Salt Marsh In Long Island Sound, Shimon C. Anisfeld, Troy D. Hill, Daonald R. Cahoon

United States Geological Survey: Staff Publications

Accelerated sea-level rise (SLR) poses the threat of salt marsh submergence, especially in marshes that are relatively low-lying. At the same time, restoration efforts are producing new low-lying marshes, many of which are thriving and avoiding submergence. To understand the causes of these different fates, we studied two Long Island Sound marshes: one that is experiencing submergence and mudflat expansion, and one that is undergoing successful restoration. We examined sedimentation using a variety of methods, each of which captures different time periods and different aspects of marsh elevation change: surface-elevation tables, marker horizons, sediment cores, and sediment traps. We also …

Endangered Species Research In The Caribbean, James W. Wiley

United States Geological Survey: Staff Publications

Although indigenous Amerindian populations adversely affected the biota of their island environments, it was not until the arrival of Europeans that populations of many plant and animal species in the Caribbean Islands declined dramatically (Snyder and others, 1987). Island species are particularly vulnerable to changes in the environment, which, in the extreme, can lead to their extinction. The small populations of many species that occupy islands have limited gene pools and typically show extremes of specialization, characteristics that place those species at high risk for decline and extinction with rapid environmental change. The most important factor in the decline of …

The Bird Banding Laboratory: Support For And Collaboration With Research At Patuxent, John Tautin

United States Geological Survey: Staff Publications

Located at Patuxent Research Refuge (PRR) and functionally part of the Patuxent Wildlife Research Center (Patuxent), Laurel, MD, the Bird Banding Laboratory (BBL) is the service and administrative center for bird banding in the United States. Over the years, the BBL has been associated with both the PRR and Patuxent, which collectively are commonly referred to by the public (and in this chapter) as “Patuxent.” The BBL issues permits and bands; supplies banding software, instructional materials, and technical advice; coordinates the use of auxiliary markers such as neck collars and radio transmitters; serves as the repository for banding records and …

Endangered Species Research In Hawaii: The Early Years (1965–87), Michael J. Scott, Cameron B. Kepler

United States Geological Survey: Staff Publications

Hawaii is an ecologically isolated archipelago 2,500 miles from the nearest continent. Its isolation resulted in a taxonomically unbalanced flora and fauna with remarkable examples of adaptive radiation among those groups of organisms that won the dispersal sweepstakes. It was one of the last oceanic island groups to be populated by humans, about 900 A.D. by Polynesian travelers and in 1778 by Europeans. Relatively recent colonization by humans did not save it, however, from the biodiversity losses suffered by other isolated archipelagos—it only delayed them (Scott and others, 1988; Pratt and others, 2009a).

Control And Optimization Of A Staged Laser-Wakefield Accelerator, Grigory V. Golovin, Sudeep Banerjee, Shouyuan Chen, Nathan D. Powers, Cheng Liu, Wenchao Yan, Jia Zhang, Ping Zhang, Baozhen Zhao, Donald Umstadter

Donald Umstadter Publications

We report results of an experimental study of laser-wakefield acceleration of electrons, using a staged device based on a double-jet gas target that enables independent injection and acceleration stages. This novel scheme is shown to produce stable, quasi-monoenergetic, and tunable electron beams. We show that optimal accelerator performance is achieved by systematic variation of five critical parameters. For the injection stage, we show that the amount of trapped charge is controlled by the gas density, composition, and laser power. For the acceleration stage, the gas density and the length of the jet are found to determine the final electron energy. …

On The Ising Character Of The Quantum-Phase Transition In Lihof4, Ralph Skomski

Ralph Skomski Publications

It is investigated how a transverse magnetic field affects the quantum-mechanical character of LiHoF₄, a system generally considered as a textbook example for an Ising-like quantum-phase transition. In small magnetic fields, the low-temperature behavior of the ions is Ising-like, involving the nearly degenerate low-lying J_z = ± 8 doublet. However, as the transverse field increases, there is a substantial admixture of states having | J_z | < 8. Near the quantum-phase-transition field, the system is distinctively non-Ising like, and all J_z eigenstates yield ground-state contributions of comparable magnitude. A classical analog to this mechanism is the micromagnetic single point in magnets with uniaxial anisotropy. Since Ho³⁺ has …

Momentum Exchange In The Electron Double-Slit Experiment, Herman Batelaan, Eric Jones, Wayne Cheng-Wei Huang, Roger Bach

Department of Physics and Astronomy: Faculty Publications

We provide support for the claim that momentum is conserved for individual events in the electron double slit experiment. The natural consequence is that a physical mechanism is responsible for this momentum exchange, but that even if the fundamental mechanism is known for electron crystal diffraction and the Kapitza–Dirac effect, it is unknown for electron diffraction from nano-fabricated double slits. Work towards a proposed explanation in terms of particle trajectories affected by a vacuum field is discussed. The contentious use of trajectories is discussed within the context of oil droplet analogues of double slit diffraction.

Intertemporal Similarity: Discounting As A Last Resort, Jeffrey R. Stevens

Jeffrey Stevens Publications

Standard models of intertemporal choice assume that individuals discount future payoffs by integrating reward amounts and time delays to generate a discounted value. Alternative models propose that, rather than integrate across them, individuals compare within attributes (amounts and delays) to determine if differences in one attribute outweigh differences in another attribute. For instance, Leland (2002) and Rubinstein (2003) propose models that 1) compare the two reward amounts to determine whether they are similar, 2) compare the similarity of the two time delays, and then 3) make a decision based on these similarity judgments. Here, I tested discounting models against attribute-based …

Image Harvest: An Open-Source Platform For High-Throughput Plant Image Processing And Analysis, Avi C. Knecht, Malachy T. Campbell, Adam Caprez, David R. Swanson, Harkamal Walia

Holland Computing Center: Faculty Publications

High-throughput plant phenotyping is an effective approach to bridge the genotype-to-phenotype gap in crops. Phenomics experiments typically result in large-scale image datasets, which are not amenable for processing on desktop computers, thus creating a bottleneck in the image-analysis pipeline. Here, we present an open-source, flexible image-analysis framework, called Image Harvest (IH), for processing images originating from high-throughput plant phenotyping platforms. Image Harvest is developed to perform parallel processing on computing grids and provides an integrated feature for metadata extraction from large-scale file organization. Moreover, the integration of IH with the Open Science Grid provides academic researchers with the computational resources …

The Unforeseen Evolution Of Technology, Dylan White

Nebraska College Preparatory Academy: Senior Capstone Projects

Technology has evolved in the past two decades to alter how countries and their people live in the present day. Said technology has also both solved and created new problems for world powers (i.e. the U.S. and China) to face. Issues of cyber security and cyber surveillance are already potential problems that need to be addressed, where topics like cyber warfare need to be closely monitored with time. All of these are potentially underestimated threats to civil liberties, and to countries in their entirety.

I agree with the findings in my project… • The United States is a model to …

Brawn, Carey Ford

Allusions

No abstract provided.

The Development Of A Human Operator Informatic Model (Hoim) Incorporating The Effects Of Non-Invasive Brain Stimulation On Information Processing While Performing Multi-Attribute Task Battery (Matb), Justin Nelson

Browse all Theses and Dissertations

Multitasking has become an integral attribute associated with military operations in tasks such as cyber defense operators, remotely piloted aircraft (RPA) operators and air traffic controllers. These tasks are monotonous and repetitive in nature requiring the human operator to interpret and process information that may exceed their mental capability. When the human operator can no longer effectively process and respond to the critical incoming information, an asymptotic limit known as the multitasking throughput capacity (MTC) will be present. At this point, critical target detection and reaction times may degrade resulting in a decrement in performance. The objective of this research …

An Approach To Implement Kahn's Technique With Dynamic Power Supply, Sowjanya Kommu

Browse all Theses and Dissertations

Radio-frequency power amplifiers are an integral part of today's communication systems. Primary importance is given to improve its efficiency and linearity, which are required for the effective signal transmission. Three main architectures on which, the efficiency of communication systems are based on are: (a) Kahn's technique, (b) Doherty's power amplifiers, and (c) Cheireix out-phasing modulation. Several schemes to implement these techniques exist in literature and their study is very diverse. In this thesis, a detailed literature survey on these techniques is presented, which includes their operation, properties, advantages, disadvantages, and areas of potential applications. This main objective of this thesis …

Crystal Dynamics Of Zinc Chalcogenides Iii: An Application To Znte, Jay Prakash Dubey, Raj Kishor Tiwari, Kripa Shankar Upadhyaya, Pramod Kumar Pandey

Turkish Journal of Physics

We report the results of a theoretical study on phonon dispersion curves (PDCs) along the three principal symmetry directions, Debye temperature variation, combined density of states (CDS) curves, two-phonon Raman/IR peaks, and anharmonic elastic properties (third order elastic constants and their pressure derivatives) of ZnTe. This new van der Waals three-body force rigid shell model (VTRSM) incorporates the effect of van der Waals interactions and three-body interactions into the rigid shell model of zinc blende structure, where the short range interactions are operative up to the second neighbors. Our results are in good agreement with the available measured data for …

The Magnetic Properties Of A Quantum Dot In A Magnetic Field, Ayham Shaer, Mohammad Elsaid, Musa Elhasan

Turkish Journal of Physics

We calculate the magnetization and susceptibility of two interacting electrons confined in a quantum dot presented in a magnetic field by solving the Hamiltonian using the exact diagonalization method. We investigate the dependence of the magnetization and susceptibility on temperature, magnetic field, and confining frequency. The singlet-triplet transitions in the ground state of the quantum dot spectra and the corresponding jumps in the magnetization curves are shown. The comparisons show that our results are in very good agreement with reported works.

Thermal Diffusion In Thin Plates And Coatings: Influence Of Thickness And Substrate Material, Harshan Soumya, Jacob Philip

Turkish Journal of Physics

The dependence of thermal diffusivity/conductivity on thickness for a variety of coatings and free-standing thin metallic plates was measured using a traveling photothermal technique. The selected materials have large differences in terms of their thermal conductivity. Measurements were carried out on coatings prepared on substrates with two widely different values for thermal conductivity to bring out the influence of substrate thermal conductivity on the thermal diffusivity/conductivity of the coating. Thermal diffusivity/conductivity increases exponentially with coating thickness with the value saturating at a definite thickness. The variation follows an empirical relation, which can predict thermal diffusivity of a coating at any …

An Approach Based On Neural Computation To Simulate Transition Metals Using Tight Binding Measurements, Adel Belayadi, Boualem Bourahla, Leila Ait-Gougam, Fawzia Mekideche-Chafa

Turkish Journal of Physics

A theoretical study of neural networks modeling, based on the tight binding approach, is proposed in this study. The aim of the present contribution is to establish a network topology to compute the binding energy parameters of transition metals. However, because of the different types of crystallization fcc, bcc, hcp, and sc of transition metals, neural network topology determination cannot be easily established, i.e. it would not be able to collect the data to feed the neurocomputing model. Hence, in order to overcome this problem, it would be helpful to distinguish one common structure from fcc, bcc, hcp, and sc. …

Determination Of The Effective Atomic Numbers Of Fe$_{X}$Cu$_{1-X} $Binary Ferroalloys Using A Nondestructive Technique: Rayleigh-To-Compton Scattering Ratio, Mehmet Büyükyildiz

Turkish Journal of Physics

The aim of the present study is to determine effective atomic numbers ($Z_{eff})$ of Fe$_{x}$Cu$_{1-x} $ binary ferroalloys using scattering of 59.54 keV gamma photons at 130$^{\circ}$ ($x=4.36{{\unicode{x212B}}}^{-1})$ scattering angle. For this purpose, the Rayleigh ($R)$ and Compton ($C)$ scattering intensities for the given alloys were measured using a monoenergetic beam of 59.54 keV gamma rays and the Rayleigh-to-Compton scattering ratio $R/C $was determined. Then the $Z_{eff}$ values of these alloys were determined by interpolating the $R/C$ of the material using the $R/C$ data of adjacent elements in between the $R/C$ of the alloys. For comparison, $Z_{eff}$s of alloys were …

Calculation Of Thermophysical Properties Of Magnesium Antimonide ($\Alpha $-Mg$_{3}$Sb$_{2})$, Seçki̇n Dündar Günay

Turkish Journal of Physics

Magnesium antimonide ($\alpha $-Mg$_{3}$Sb$_{2})$ is investigated by molecular dynamics simulation to find thermophysical properties. Lattice parameters and heat capacities are calculated from room temperature to the melting point. Nearest neighbor distances of ions are measured from the radial distribution function and compared with experimental values. Bulk properties like elastic constants and bulk and shear moduli are found and tabulated with first-principle and experimental data.

Effect Of Glow Discharge Plasma On Step Index Polymer Optical Fiber Parameters, Mohamed Medhat, El-Sayed El-Zaiat, Mohamed Sauday, Mona Omar, Hassanein Shaaban

Turkish Journal of Physics

DC glow discharge plasma of power 40 W was applied to step index polymer optical fibers for different exposure times. Nitrogen, oxygen, and hydrogen gases were used to obtain the glow discharge. The fiber core material was poly methyl methacrylate and the cladding was fluorinated polymer. The effect of plasma on the optical parameters, such as core index profile, cladding index, and the numerical aperture, was studied by multiple beam interference fringes and Fourier transformation of infrared spectroscopy spectra. It was found that the plasma treatment affected the optical parameters of both the cladding and the core regions of optical …

Local Dynamics And Global Stability Of Certain Second-Order Rational Difference Equation With Quadratic Terms, S. Jasarevic Hrustic, Mustafa Kulenovic, M. Nurkanovic

Mathematics Faculty Publications

We present a complete local dynamics and investigate the global dynamics of the following second-order difference equation: x_n+1 = (Ax² + Ex_n-1 + F) / (ax_n² + ex_n-1 + f), n = 0, 1, 2, . . ., where the parameters A, E, F, a, e, and f are nonnegative numbers with condition A + E + F > 0, a + e + f > 0, and initial conditions x_-1, x₀ are arbitrary nonnegative numbers such that ax_n² + …

Hemoglobin–Oxygen Affinity In High-Altitude Vertebrates: Is There Evidence For An Adaptive Trend?, Jay F. Storz

Jay F. Storz Publications

In air-breathing vertebrates at high altitude, fine-tuned adjustments in hemoglobin (Hb)–O₂ affinity provide an energetically efficient means of mitigating the effects of arterial hypoxemia. However, it is not always clear whether an increased or decreased Hb–O₂ affinity should be expected to improve tissue O₂ delivery under different degrees of hypoxia, due to the inherent trade-off between arterial O₂ loading and peripheral O₂ unloading. Theoretical results indicate that the optimal Hb–O₂ affinity varies as a non-linear function of environmental O₂ availability, and the threshold elevation at which an increased Hb–O₂ affinity becomes advantageous …

Seasonal Variation In The Ndvi–Species Richness Relationship In A Prairie Grassland Experiment (Cedar Creek), Ran Wang, John A. Gamon, Rebecca A. Montgomery, Philip A. Townsend, Arthur I. Zygielbaum, Keren Bitan, David Tilman, Jeannine Cavender-Bares

School of Natural Resources: Faculty Publications

Species richness generally promotes ecosystem productivity, although the shape of the relationship varies and remains the subject of debate. One reason for this uncertainty lies in the multitude of methodological approaches to sampling biodiversity and productivity, some of which can be subjective. Remote sensing offers new, objective ways of assessing productivity and biodiversity. In this study, we tested the species richness–productivity relationship using a common remote sensing index, the Normalized Difference Vegetation Index (NDVI), as a measure of productivity in experimental prairie grassland plots (Cedar Creek). Our study spanned a growing season (May to October, 2014) to evaluate dynamic changes …