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Articles 144301 - 144330 of 302471

Full-Text Articles in Physical Sciences and Mathematics

Au Nanostructured Surfaces For Electrochemical And Localized Surface Plasmon Resonance-Based Monitoring Of Α-Synuclein-Small Molecule Interactions., Xin R Cheng, Gregory Q Wallace, François Lagugné-Labarthet, Kagan Kerman Feb 2015

Au Nanostructured Surfaces For Electrochemical And Localized Surface Plasmon Resonance-Based Monitoring Of Α-Synuclein-Small Molecule Interactions., Xin R Cheng, Gregory Q Wallace, François Lagugné-Labarthet, Kagan Kerman

Chemistry Publications

In this proof-of-concept study, the fabrication of novel Au nanostructured indium tin oxide (Au-ITO) surfaces is described for the development of a dual-detection platform with electrochemical and localized surface plasmon resonance (LSPR)-based biosensing capabilities. Nanosphere lithography (NSL) was applied to fabricate Au-ITO surfaces. Oligomers of α-synuclein (αS) were covalently immobilized to determine the electrochemical and LSPR characteristics of the protein. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were performed using the redox probe [Fe(CN)6](3-/4-) to detect the binding of Cu(II) ions and (-)-epigallocatechin-3-gallate (EGCG) to αS on the Au-ITO surface. Electrochemical and LSPR data were complemented by Thioflavin-T (ThT) …


Fluctuating Asymmetry In Menidia Beryllina Before And After The 2010 Deepwater Horizon Oil Spill, Savannah A. Michaelsen, Jacob F. Schaefer, Mark S. Peterson Feb 2015

Fluctuating Asymmetry In Menidia Beryllina Before And After The 2010 Deepwater Horizon Oil Spill, Savannah A. Michaelsen, Jacob F. Schaefer, Mark S. Peterson

Faculty Publications

Assessing the impacts of the Deepwater Horizon oil spill with a dependable baseline comparison can provide reliable insight into environmental stressors on organisms that were potentially affected by the spill. Fluctuating asymmetry (small, non-random deviations from perfect bilateral symmetry) is an informative metric sensitive to contaminants that can be used to assess environmental stress levels. For this study, the well-studied and common Gulf of Mexico estuarine fish, Menidia beryllina, was used with pre and post-oil spill collections. Comparisons of fluctuating asymmetry in three traits (eye diameter, pectoral fin length, and pelvic fin length) were made pre and post-oil spill …


Au Nanostructured Surfaces For Electrochemical And Localized Surface Plasmon Resonance-Based Monitoring Of Α-Synuclein-Small Molecule Interactions., Xin R Cheng, Gregory Q Wallace, François Lagugné-Labarthet, Kagan Kerman Feb 2015

Au Nanostructured Surfaces For Electrochemical And Localized Surface Plasmon Resonance-Based Monitoring Of Α-Synuclein-Small Molecule Interactions., Xin R Cheng, Gregory Q Wallace, François Lagugné-Labarthet, Kagan Kerman

Chemistry Publications

In this proof-of-concept study, the fabrication of novel Au nanostructured indium tin oxide (Au-ITO) surfaces is described for the development of a dual-detection platform with electrochemical and localized surface plasmon resonance (LSPR)-based biosensing capabilities. Nanosphere lithography (NSL) was applied to fabricate Au-ITO surfaces. Oligomers of α-synuclein (αS) were covalently immobilized to determine the electrochemical and LSPR characteristics of the protein. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were performed using the redox probe [Fe(CN)6](3-/4-) to detect the binding of Cu(II) ions and (-)-epigallocatechin-3-gallate (EGCG) to αS on the Au-ITO surface. Electrochemical and LSPR data were complemented by Thioflavin-T (ThT) …


Cosm News, Georgia Southern University Feb 2015

Cosm News, Georgia Southern University

College of Science and Mathematics News (2012-2019)

  • COSM participates in Arbor Day Celebration


Multimode Analysis Of Nanoscale Biomolecular Interactions, Purushottam Babu Tiwari Feb 2015

Multimode Analysis Of Nanoscale Biomolecular Interactions, Purushottam Babu Tiwari

FIU Electronic Theses and Dissertations

Biomolecular interactions, including protein-protein, protein-DNA, and protein-ligand interactions, are of special importance in all biological systems. These interactions may occer during the loading of biomolecules to interfaces, the translocation of biomolecules through transmembrane protein pores, and the movement of biomolecules in a crowded intracellular environment. The molecular interaction of a protein with its binding partners is crucial in fundamental biological processes such as electron transfer, intracellular signal transmission and regulation, neuroprotective mechanisms, and regulation of DNA topology. In this dissertation, a customized surface plasmon resonance (SPR) has been optimized and new theoretical and label free experimental methods with related analytical …


Karst Porosity Estimations From Archive Cave Surveys - Studies In The Buda Thermal Karst System (Hungary), Gáspár Albert, Magdolna Virág, Anita Erőss Feb 2015

Karst Porosity Estimations From Archive Cave Surveys - Studies In The Buda Thermal Karst System (Hungary), Gáspár Albert, Magdolna Virág, Anita Erőss

International Journal of Speleology

The Buda Thermal Karst System is located under the densely populated hills of Budapest. One of its caves (Pál-völgy Cave System) is the longest cave of Hungary with 30.1 km. The research was done in this area as a methodological study to estimate karst porosity parameters of aquifers or hydrocarbon reservoirs. In this study two modeling methods are demonstrated. The volumetric modeling method was primarily aimed to determine the macro-scale (>0.5 m) conduit porosity (referred as macroporosity) of the study area as percentage of the incorporating limestone and marl. This method is based on archive survey data (maps and …


U.S. Drought Monitor, February 24, 2015, Richard R. Heim Jr. Feb 2015

U.S. Drought Monitor, February 24, 2015, Richard R. Heim Jr.

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for February 24, 2015 (2/24/15) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


Design And Implementation Of Multi-Head Presentation Software For The Ios Platform, Michael S. Babienco Feb 2015

Design And Implementation Of Multi-Head Presentation Software For The Ios Platform, Michael S. Babienco

MS in Computer Science Project Reports

ShareSynch, currently available for both Windows and Mac OS X, is a presentation software application tailored towards evangelistic speakers with limited experience. The software has several essential features including the use of speaker notes during a presentation, support for independent slide and speaker note language, speaker note pagination with dynamic font scaling, editing of presentations and rich text speaker notes from within the application, and dynamic appeal video configuration. No known iOS application contains all of the PC software's essential features. In this paper, we discuss the design and implementation of ShareSynch on the iOS platform. The iOS version of …


Modeling Predator Habitat To Enhance Reintroduction Planning, Shiloh Michael Halsey, William J. Zielinski, Robert M. Scheller Feb 2015

Modeling Predator Habitat To Enhance Reintroduction Planning, Shiloh Michael Halsey, William J. Zielinski, Robert M. Scheller

Environmental Science and Management Faculty Publications and Presentations

Context

The success of species reintroduction often depends on predation risk and spatial estimates of predator habitat. The fisher (Pekania pennanti) is a species of conservation concern and populations in the western United States have declined substantially in the last century. Reintroduction plans are underway, but the ability of the species to establish a selfsustaining population is affected by predation from its primary predator, the bobcat (Lynx rufus).

Objectives

To develop a habitat model that incorporates both habitat of the focal species and the spatial patterning of predator habitat. To locate areas of densely aggregated habitat that would be suitable …


Analysis Of Electrostatic Breakdown Sites, Sam Hansen Feb 2015

Analysis Of Electrostatic Breakdown Sites, Sam Hansen

Physics Capstone Projects

Materials potentially suitable for spacecraft construction were exposed to electrostatic discharge in the USU Materials Physics Group lab, with hopes of identifying samples that possess greater resistance to breakdown. Breakdown shape and size may be important to determining material suitability for spacecraft construction. The discharge damage sites of tested samples were examined, measured and logged into a matrix file for data analysis. Once logged, data were sorted within the matrix and compared graphically to identify trends. Several interesting discoveries were made. LDPE sample breakdown sites are significantly larger than Kapton varieties. We were unable to link increased energy inputs to …


Non-Isomorphic Real Simple Lie Algebras Of The Same Complex Type And Character, Ian M. Anderson Feb 2015

Non-Isomorphic Real Simple Lie Algebras Of The Same Complex Type And Character, Ian M. Anderson

Tutorials on... in 1 hour or less

Complex simple Lie algebras are classified by their root types. The type of a real simple Lie algebra is the root type of the associated complex algebra. The character of a real simple Lie algebra is the signature of its Killing form.

For many root types, the character is sufficient to uniquely classify the corresponding real Lie algebras. However, one should not take this statement to be literally true – there are a few cases where the character does not suffice to distinguish all possible real forms.

In this worksheet we will show that the 2 real non-isomorphic Lie algebras …


Design, Synthesis And Applications Of Polymer Biomaterials, Frankie Costanza Feb 2015

Design, Synthesis And Applications Of Polymer Biomaterials, Frankie Costanza

USF Tampa Graduate Theses and Dissertations

The emergence of antibiotic resistant bacteria has prompted the research into novel kinds of antibacterial small molecules and polymers. Nature has solved this issue with the use of cationic antimicrobial peptides, which act as nonspecific antibiotics against invading species. Herein, we have tried to mimic this general mechanism in a biocompatible and biodegradable polymer micelle based on the polymerization of naturally occurring amino acids lysine and phenylalanine linked to a PEG tether. This amphiphilic structure allows for the spontaneous collapse into stable nanoparticles in solution, which contains a hydrophilic outer layer and a hydrophobic core. Our polymers have shown activity …


Measurement Of The Production Cross Section Ratio Σ(Χb2(1p))/Σ(Χb1(1p))In Pp Collisions At √S=8tev, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez Feb 2015

Measurement Of The Production Cross Section Ratio Σ(Χb2(1p))/Σ(Χb1(1p))In Pp Collisions At √S=8tev, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

A measurement of the production cross section ratio σ(χb2(1P))/σ(χb1(1P))is presented. The χb1(1P)and χb2(1P)bottomonium states, promptly produced in pp collisions at √s=8TeV, are detected by the CMS experiment at the CERN LHC through their radiative decays χb1,2(1P) →ϒ(1S) +γ. The emitted photons are measured through their conversion to e+e−pairs, whose reconstruction allows the two states to be resolved. The ϒ(1S)is measured through its decay to two muons. An event sample corresponding to an integrated luminosity of 20.7fb−1is used to measure the cross section ratio in a phase-space region defined by the photon pseudorapidity, |ηγ| <1.0; the ϒ(1S)rapidity, |yϒ| <1.5; and the ϒ(1S)transverse momentum, 7


Demonstrating Continuous Variable Einstein–Podolsky–Rosen Steering In Spite Of Finite Experimental Capabilities Using Fano Steering Bounds, James Schneeloch, Samuel H. Knarr, Gregory A. Howland, John C. Howell Feb 2015

Demonstrating Continuous Variable Einstein–Podolsky–Rosen Steering In Spite Of Finite Experimental Capabilities Using Fano Steering Bounds, James Schneeloch, Samuel H. Knarr, Gregory A. Howland, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We show how one can demonstrate continuous-variable Einstein–Podolsky–Rosen (EPR) steering without needing to characterize entire measurement probability distributions. To do this, we develop a modified Fano inequality useful for discrete measurements of continuous variables and use it to bound the conditional uncertainties in continuous-variable entropic EPR-steering inequalities. With these bounds, we show how one can hedge against experimental limitations including a finite detector size, dead space between pixels, and any such factors that impose an incomplete sampling of the true measurement probability distribution. Furthermore, we use experimental data from the position and momentum statistics of entangled photon pairs in parametric …


The Evolution Of Non-Market Valuation Of U.S. Coastal And Marine Resources, Douglas Lipton, Dan K. Lew, Kristy Wallmo, Peter Wiley, Anthony Dvarskas Feb 2015

The Evolution Of Non-Market Valuation Of U.S. Coastal And Marine Resources, Douglas Lipton, Dan K. Lew, Kristy Wallmo, Peter Wiley, Anthony Dvarskas

Journal of Ocean and Coastal Economics

At the federal level, particularly within the National Oceanic and Atmospheric Administration (NOAA), regulatory and programmatic needs have driven the continued development and application of non-market valuation approaches to marine and coastal resources. The evolution of these valuation approaches not only entails adopting the recommendations of the 1993 NOAA blue ribbon panel on contingent valuation, but also an expansion of stated preference approaches with increased use of stated preference choice experiments. Revealed preference approaches have also advanced with more sophisticated random utility models. We provide an overview of this evolution in the areas of natural resources damage assessment, protected resources, …


Abstracts Volume 1 2014 Spanish, The Editors Feb 2015

Abstracts Volume 1 2014 Spanish, The Editors

Journal of Ocean and Coastal Economics

Abstracts to Volume 2014 in Spanish


Reconsidering The Impact Of Cs1 On Novice Attitudes, Amber Settle, John Lalor, Theresa Steinbach Feb 2015

Reconsidering The Impact Of Cs1 On Novice Attitudes, Amber Settle, John Lalor, Theresa Steinbach

Amber Settle

Student success in an introductory programing course is crucial, both because it influences retention and because student attitudes and habits in a first course can have a lasting impact on student success in computer science as a field. In this paper we present results about student attitudes and habits before and after a CS1 class. Statistically significant attitude differences were found in three areas: students were less likely to report they were good at programming, more likely to agree they are challenged by programming problems they can't understand immediately, and are less likely to report that computer science allows them …


Identification And Quantification Of Gaseous Organic Compounds Emitted From Biomass Burning Using Two-Dimensional Gas Chromatography–Time-Of-Flight Mass Spectrometry, L. E. Hatch, W. Luo, J. F. Pankow, Robert Yokelson, C. Stockwell, K. C. Barsanti Feb 2015

Identification And Quantification Of Gaseous Organic Compounds Emitted From Biomass Burning Using Two-Dimensional Gas Chromatography–Time-Of-Flight Mass Spectrometry, L. E. Hatch, W. Luo, J. F. Pankow, Robert Yokelson, C. Stockwell, K. C. Barsanti

Chemistry and Biochemistry Faculty Publications

The current understanding of secondary organic aerosol (SOA) formation within biomass burning (BB) plumes is limited by the incomplete identification and quantification of the non-methane organic compounds (NMOCs) emitted from such fires. Gaseous organic compounds were collected on sorbent cartridges during laboratory burns as part of the fourth Fire Lab at Missoula Experiment (FLAME-4) and analyzed by two-dimensional gas chromatography-time-of-flight mass spectrometry (GC x GC-ToFMS). The sensitivity and resolving power of GC x GC-ToFMS allowed the acquisition of the most extensive data set of BB NMOCs to date, with measurements from 708 positively or tentatively identified compounds. Estimated emission factors …


Temperature Dependence Of Anisotropic Magnetoresistance In Antiferromagnetic Sr2Iro4, C. Wang, H. Seinige, Gang Cao, J.-S. Zhou, J. B. Goodenough, M. Tsoi Feb 2015

Temperature Dependence Of Anisotropic Magnetoresistance In Antiferromagnetic Sr2Iro4, C. Wang, H. Seinige, Gang Cao, J.-S. Zhou, J. B. Goodenough, M. Tsoi

Center for Advanced Materials Faculty Publications

Temperature-dependent magnetotransport properties of the antiferromagnetic semiconductor Sr2IrO4 are investigated with point-contact devices. The point-contact technique allows to probe very small volumes and, therefore, to look for electronic transport on a microscopic scale. Point-contact measurements with single crystals of Sr2IrO4 were intended to see whether the additional local resistance associated with a small contact area between a sharpened Cu tip and the antiferromagnet shows magnetoresistance (MR) such as that seen in bulk crystals. Point-contact measurements at liquid nitrogen temperature revealed large MRs (up to 28%) for modest magnetic fields (250 mT) applied within an …


Beyond The Angle Of Repose: A Review And Synthesis Of Landslide Processes In Response To Rapid Uplift, Eel River, Northern Eel River, Northern California, Joshua J. Roering, Benjamin H. Mackey, Alexander L. Handwerger, Adam M. Booth, David A. Schmidt, Georgina L. Bennett, Corina Cerovski-Darriau Feb 2015

Beyond The Angle Of Repose: A Review And Synthesis Of Landslide Processes In Response To Rapid Uplift, Eel River, Northern Eel River, Northern California, Joshua J. Roering, Benjamin H. Mackey, Alexander L. Handwerger, Adam M. Booth, David A. Schmidt, Georgina L. Bennett, Corina Cerovski-Darriau

Geology Faculty Publications and Presentations

In mountainous settings, increases in rock uplift are often followed by a commensurate uptick in denudation as rivers incise and steepen hillslopes, making them increasingly prone to landsliding as slope angles approach a limiting value. For decades, the threshold slope model has been invoked to account for landslide-driven increases in sediment flux that limit topographic relief, but the manner by which slope failures organize themselves spatially and temporally in order for erosion to keep pace with rock uplift has not been well documented. Here, we review past work and present new findings from remote sensing, cosmogenic adionuclides, suspended sediment records, …


Comparative Response Of Dms And Dmsp Concentrations In Symbiodinium Clades C1 And D1 Under Thermal Stress, Elisabeth Deschaseaux, V Beltran, Graham Jones, Myrna Deseo, H Swan, Peter Harrison, Bradley Eyre Feb 2015

Comparative Response Of Dms And Dmsp Concentrations In Symbiodinium Clades C1 And D1 Under Thermal Stress, Elisabeth Deschaseaux, V Beltran, Graham Jones, Myrna Deseo, H Swan, Peter Harrison, Bradley Eyre

Dr Myrna A Deseo

Coral-associated Symbiodinium are known to produce dimethylsulphide (DMS) and dimethylsulphoniopropionate (DMSP), two biogenic sulphur compounds that potentially play a role in the algal antioxidant system and climate regulation. Coral resistance to bleaching and oxidative stress partly depends upon the capacity of their symbionts to respond to environmental stressors, with DMS and DMSP possibly contributing to this response. Under increasing sea surface temperatures, zooxanthellate corals might dominantly associate with more thermally tolerant clades of Symbiodinium, of which the nutritional and biochemical contribution to the holobiont remains unknown. Here, the production of DMS and DMSP under increasing temperature (from 26 °C …


Some Conjugacy Problems In Algebraic Groups., Anirban Bose Dr. Feb 2015

Some Conjugacy Problems In Algebraic Groups., Anirban Bose Dr.

Doctoral Theses

In this thesis we address two problems related to the study of algebraic groups and Lie groups. The first one deals with computation of an invariant called the genus number of a connected reductive algebraic group over an algebraically closed field and that of a compact connected Lie group. The second problem is about characterisation of real elements in exceptional groups of type F4 defined over an arbitrary field. Let G be a connected reductive algebraic group over an algebraically closed field or a compact connected Lie group. Let ZG(x) denote the centralizer of x ∈ G. Define the genus …


Bubble Mobility In Mud And Magmatic Volcanoes, Aaron Tran, Maxwell L. Rudolph, Michael Manga Feb 2015

Bubble Mobility In Mud And Magmatic Volcanoes, Aaron Tran, Maxwell L. Rudolph, Michael Manga

Geology Faculty Publications and Presentations

The rheology of particle-laden fluids with a yield stress, such as mud or crystal-rich magmas, controls the mobility of bubbles, both the size needed to overcome the yield stress and their rise speed. We experimentally measured the velocities of bubbles and rigid spheres in mud sampled from the Davis-Schrimpf mud volcanoes adjacent to the Salton Sea, Southern California. Combined with previous measurements in the polymer gel Carbopol, we obtained an empirical model for the drag coefficient and bounded the conditions under which bubbles overcome the yield stress. Yield stresses typical of mud and basaltic magmas with sub-mm particles can immobilize …


Developing A Comparative Marine Socio-Economic Framework For The European Atlantic Area, Naomi S. Foley, Rebecca Corless, Marta Escapa, Frances Fahy, Javier Fernandez-Macho, Susana Gabriel, Pilar Gonzalez, Stephen Hynes, Regis Kalaydjian, Susana Moreira, Kieran Moylan, Arantza Murillas, Michael O'Brien, Katherine Simpson, Dugald Tinch Feb 2015

Developing A Comparative Marine Socio-Economic Framework For The European Atlantic Area, Naomi S. Foley, Rebecca Corless, Marta Escapa, Frances Fahy, Javier Fernandez-Macho, Susana Gabriel, Pilar Gonzalez, Stephen Hynes, Regis Kalaydjian, Susana Moreira, Kieran Moylan, Arantza Murillas, Michael O'Brien, Katherine Simpson, Dugald Tinch

Journal of Ocean and Coastal Economics

Availability and easy access to a wide range of natural and human-activity data on the oceans and coastal regions of Europe is the basis for strategic decision-making on coastal and marine policy. Strategies within Europe’s Integrated Maritime Policy, including the Maritime Strategy for the Atlantic Area, Blue Growth, Maritime Spatial Planning and Marine Data and Knowledge, require coherent and comparable socio-economic data across European countries. Similarly, the Marine Strategy Framework Directive requires member states to carry out economic and social analysis of their waters and the reformed Common Fisheries Policy includes a social dimension requiring socio-economic data. However, the availability …


Assessing The Economic Costs Of Water Pollution In The Yangtze River, China, Xiaoli Zhang Feb 2015

Assessing The Economic Costs Of Water Pollution In The Yangtze River, China, Xiaoli Zhang

Journal of Ocean and Coastal Economics

Water pollution of the Yangtze River basin is very serious. Studies have shown that from the upper to the lower river, the water volume decreases and development and pollution increase, especially in trans-boundary areas. The Yangtze Estuary is located at the intersection of Jiangsu Province and Shanghai where the waters flow directly into the East China Sea. The estuary provides drinking water to many people and serves multiple other functions, including agricultural irrigation, tourism, and aquaculture. It plays a pivotal role in the local social and economic development and in people’s general wellbeing. Directly or indirectly, the pollution of the …


What Have We Learned From The Deepwater Horizon Disaster? An Economist’S Perspective, Daniel R. Petrolia Feb 2015

What Have We Learned From The Deepwater Horizon Disaster? An Economist’S Perspective, Daniel R. Petrolia

Journal of Ocean and Coastal Economics

This paper outlines what we have learned about the impacts of the Deepwater Horizon (DWH) oil disaster from the economics discipline as well as what effect the DWH disaster has had on the economics discipline. It appears that what we know about the economic impact of the DWH spill today is limited, possibly because such analysis is tied up in the federal Natural Resource Damage Assessment (NRDA) process and other state-led efforts. There is evidence, however, that the NRDA process has changed over time to de-emphasize economic valuation of damages. There is also evidence that economists may be producing fewer …


Mechanism Of N -Hydroxylation Catalyzed By Flavin-Dependent Monooxygenases, Somayesadat Badieyan, Robert D. Bach, Pablo Sobrado Feb 2015

Mechanism Of N -Hydroxylation Catalyzed By Flavin-Dependent Monooxygenases, Somayesadat Badieyan, Robert D. Bach, Pablo Sobrado

Chemistry Faculty Research & Creative Works

Aspergillus fumigatus siderophore (SidA), a member of class B flavin-dependent monooxygenases, was selected as a model system to investigate the hydroxylation mechanism of heteroatom-containing molecules by this group of enzymes. SidA selectively hydroxylates ornithine to produce N5-hydroxyornithine. However, SidA is also able to hydroxylate lysine with lower efficiency. In this study, the hydroxylation mechanism and substrate selectivity of SidA were systematically studied using DFT calculations. The data show that the hydroxylation reaction is initiated by homolytic cleavage of the O-O bond in the C4a-hydroperoxyflavin intermediate, resulting in the formation of an internal hydrogen-bonded hydroxyl radical (HO•). As the HO• moves …


Tropical Determinant On Transportation Polytopes, Sailaja Gajula, Ivan Soprunov, Jenya Soprunova Feb 2015

Tropical Determinant On Transportation Polytopes, Sailaja Gajula, Ivan Soprunov, Jenya Soprunova

Mathematics and Statistics Faculty Publications

Let Dk,l(m, n)be the set of all the integer points in the transportation polytope of kn × ln matrices with row sums lm and column sums km. In this paper we find the sharp lower bound on the tropical determinant over the set Dk,l(m, n). This integer piecewise linear programming problem in arbitrary dimension turns out to be equivalent to an integer non-linear (in fact, quadratic) optimization problem in dimension two. We also compute the sharp upper bound on a modification of the tropical determinant, where the maximum over all the transversals in a matrix is …


Global Warming And Population Responses Among Great Plains Birds, Paul A. Johnsgard Feb 2015

Global Warming And Population Responses Among Great Plains Birds, Paul A. Johnsgard

Zea E-Books Collection

Based on an analysis of 47 years (1967–2014) of Audubon Christmas Bird Counts (CBC), evidence for population changes and shifts in early winter (late December) ranges of nearly 150 species of birds in the Great Plains states is summarized, a region defined as including the Dakotas, Nebraska, Kansas, Oklahoma, and the Texas panhandle. The rationale for this study had its origins in Terry Root’s 1988 Atlas of North American Wintering Birds. Root’s landmark study provided a baseline for evaluating the nationwide winter distributions of 253 North American birds in the mid-20th century, using data from the National Audubon Society’s …


Timing Of Five Millisecond Pulsars Discovered In The Palfa Survey, P. Scholz, V. M. Kaspi, A. G. Lyne, B. W. Stappers, S. Bogdanov, J. M. Cordes, F. Crawford, R. D. Ferdman, P. C.C. Freire, J. W.T. Hessels, D. R. Lorimer, I. H. Stairs, B. Allen, A. Brazier, F. Camilo, R. F. Cardoso, S. Chatterjee, J. S. Deneva, F. A. Jenet, C. Karako-Argaman, B. Knispel, P. Lazarus, K. J. Lee, J. Van Leeuwen, R. Lynch, E. C. Madsen, M. A. Mclaughlin, S. M. Ransom, X. Siemens, L. G. Spitler Feb 2015

Timing Of Five Millisecond Pulsars Discovered In The Palfa Survey, P. Scholz, V. M. Kaspi, A. G. Lyne, B. W. Stappers, S. Bogdanov, J. M. Cordes, F. Crawford, R. D. Ferdman, P. C.C. Freire, J. W.T. Hessels, D. R. Lorimer, I. H. Stairs, B. Allen, A. Brazier, F. Camilo, R. F. Cardoso, S. Chatterjee, J. S. Deneva, F. A. Jenet, C. Karako-Argaman, B. Knispel, P. Lazarus, K. J. Lee, J. Van Leeuwen, R. Lynch, E. C. Madsen, M. A. Mclaughlin, S. M. Ransom, X. Siemens, L. G. Spitler

Physics and Astronomy Faculty Publications and Presentations

We present the discovery of five millisecond pulsars (MSPs) from the PALFA Galactic plane survey using Arecibo. Four of these (PSRs J0557+1551, J1850+0244, J1902+0300, and J1943+2210) are binary pulsars whose companions are likely white dwarfs, and one (PSR J1905+0453) is isolated. Phase-coherent timing solutions, ranging from 1 to 3 yr in length, and based on observations from the Jodrell Bank and Arecibo telescopes, provide precise determinations of spin, orbital, and astrometric parameters. All five pulsars have large dispersion measures (>100 pc cm-3, within the top 20% of all known Galactic field MSPs) and are faint (1.4 GHz flux density …