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2014

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Articles 211 - 240 of 9800

Full-Text Articles in Physical Sciences and Mathematics

How The Presence Of Plastic In The North Pacific Gyre Affects The Growth Of Thalassiosira Through Remote Sensing And Laboratory Replication, Jordynn Brennan, Hesham El-Askary Dec 2014

How The Presence Of Plastic In The North Pacific Gyre Affects The Growth Of Thalassiosira Through Remote Sensing And Laboratory Replication, Jordynn Brennan, Hesham El-Askary

Student Scholar Symposium Abstracts and Posters

Through the use of remote sensing, we are able to determine the approximate location of the garbage patch in the North Pacific Gyre. Though remote sensing does not penetrate the surface of the ocean, monthly satellite images can be analyzed to determine the rate of growth or rate of decrease of certain parameters, such as atmospheric gases, phytoplankton, and dissolved organic matter. Over the past decade, data from the Goddard Earth Sciences Data and Information Services Center (Giovanni program) has shown a significant increase in dissolved organic matter and chlorophyll a content in the area of the North Pacific Garbage …


Iranian Nuclear Proliferation And Sanctions, Bailey Nicole Burlingame Dec 2014

Iranian Nuclear Proliferation And Sanctions, Bailey Nicole Burlingame

Student Scholar Symposium Abstracts and Posters

This project will involve the current problem of nuclear development in the nation of Iran. The question involved in the election studies was, “Should we try to stop Iranian Nuclear Development by increasing sanctions, yes or no?” According to the US Department of State website, they are attempting to increase these sanctions against individuals or cooperations who can be proven to have provided aid, information, or mechanical aspects to assist the goal of Iranian nuclear proliferation. The website provides identifying information for the individuals involved. The answer to this question I believe will be determined the amount of news information …


Structural And Hydrological Controls On The Development Of A River Cave In Marble (Tapagem Cave - Se Brazil), William Sallun Filho, Bruna Medeiros Cordeiro, Ivo Karmann Dec 2014

Structural And Hydrological Controls On The Development Of A River Cave In Marble (Tapagem Cave - Se Brazil), William Sallun Filho, Bruna Medeiros Cordeiro, Ivo Karmann

International Journal of Speleology

Tapagem Cave (or Devil’s Cave) is a river cave developed in the dolomite marble karst of the Serra do André Lopes (State of São Paulo, southeastern Brazil). Although this region is a plateau with significant variation in elevation and a humid subtropical climate, the cave is an anomalous feature in the André Lopes karst because there are few other caves. The marble, which is in a synclinal structure with subjacent phyllites, is a karst aquifer perched above the regional base level (Ribeira River) and has little allogenic recharge. The cave developed on a secondary anticline on the northwest flank of …


Speleoclimate Dynamics In Santana Cave (Petar, São Paulo State, Brazil): General Characterization And Implications For Tourist Management, Heros Augusto Santos Lobo, Paulo Cesar Boggiani, José Alexandre De Jesus Perinotto Dec 2014

Speleoclimate Dynamics In Santana Cave (Petar, São Paulo State, Brazil): General Characterization And Implications For Tourist Management, Heros Augusto Santos Lobo, Paulo Cesar Boggiani, José Alexandre De Jesus Perinotto

International Journal of Speleology

Show caves provide tourists with the opportunity to have close contact with natural underground spaces. However, visitation to these places also creates a need for management measures, mainly the definition of tourist carrying capacity. The present work describes the results of climate monitoring and atmospheric profiling performed in Santana Cave (Alto Ribeira State and Tourist Park – PETAR, Brazil) between 2008 and 2011. Based on the results, distinct preliminary zones with different levels of thermal variation were identified, which classify Santana Cave as a warm trap. Two critical points along the tourist route (Cristo and Encontro Halls) were identified where …


U.S. Drought Monitor, December 9, 2014, Anthony Artusa Dec 2014

U.S. Drought Monitor, December 9, 2014, Anthony Artusa

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for December 9, 2014 (12/9/14) 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.


Collective Edge Modes Near The Onset Of A Graphene Quantum Spin Hall State, Gunpathy Murthy, Efrat Shimshoni, H. A. Fertig Dec 2014

Collective Edge Modes Near The Onset Of A Graphene Quantum Spin Hall State, Gunpathy Murthy, Efrat Shimshoni, H. A. Fertig

Physics and Astronomy Faculty Publications

Graphene subject to a strong, tilted magnetic field exhibits an insulator-metal transition tunable by tilt angle, attributed to the transition from a canted antiferromagnetic (CAF) to a ferromagnetic (FM) bulk state at filling factor ν=0. We develop a theoretical description for the spin and valley edge textures in the two phases, and the implied evolution in the nature of edge modes through the transition. In particular, we show that the CAF has gapless neutral modes in the bulk, but supports gapped charged edge modes. At the transition to the FM state the charged edge modes become gapless and are …


Assessment Of Macroinvertebrate Communities And Heavy Metal Contamination Along The Intracoastal Waterway In Fort Lauderdale, Florida, Robert Bernhard Dec 2014

Assessment Of Macroinvertebrate Communities And Heavy Metal Contamination Along The Intracoastal Waterway In Fort Lauderdale, Florida, Robert Bernhard

HCNSO Student Theses and Dissertations

Sediments from four areas adjacent to marinas and a background site in the Intracoastal Waterway were assessed for macroinvertebrate composition and heavy metal contamination. Sediment core samples were collected in 2004 and 2005 for analyses of macroinvertebrate composition and sediment grain size. Additional sediment samples were collected in 2005 for chemical analyses of metals (Al, As, Cd, Cr, Cu, Fe, Pb, Hg, Ni and Zn). MANOVA and dendograms using Bray-Curtis similarity matrices grouped the sites into two clusters: the 3 sites closest to the New River formed one group, and the two end sites formed the other. The sites nearest …


Electrochemical Synthesis Of Nanostructured Noble Metal Films For Biosensing, Jay Kishan Bhattarai Dec 2014

Electrochemical Synthesis Of Nanostructured Noble Metal Films For Biosensing, Jay Kishan Bhattarai

Dissertations

Nanostructures of noble metals (Au and Ag) are of interest because of their important intrinsic properties. Noble metals by themselves are conductive, physically robust, chemically inert, and strongly bind to thiols. However, when the nanostructures are formed, they in addition possess high surface area and unique optical properties tunable by adjusting the shape and size. All of these properties make nanostructures of noble metals suitable candidates to be used as a transducer for biosensing. Individual nanostructures might be easier to prepare but difficult to handle to be used as a transducer. Therefore, we prepared and analyzed nanostructured films/coating of noble …


C-Metrics In Gauged Stu Supergravity And Beyond, H. Lu, Justin F. Vázquez-Poritz Dec 2014

C-Metrics In Gauged Stu Supergravity And Beyond, H. Lu, Justin F. Vázquez-Poritz

Publications and Research

We construct charged generalizations of the dilaton C-metric in various fourdimensional theories, including STU gauged supergravity as well as a one-parameter family of Einstein-Maxwell-dilaton theories whose scalar potential can be expressed in terms of a superpotential. In addition, we present time-dependent generalizations of the dilaton C-metric and dilaton Ernst solutions, for which the time evolution is driven by the dilaton. These C-metric solutions provide holographic descriptions of a strongly-coupled three-dimensional field theory on the background of a black hole, a gravitational soliton, and a black hole undergoing time evolution.


Elastic Differential Cross Sections For Space Radiation Applications, Charles M. Werneth, Khin M. Maung, William P. Ford, John W. Norbury, Michael D. Vera Dec 2014

Elastic Differential Cross Sections For Space Radiation Applications, Charles M. Werneth, Khin M. Maung, William P. Ford, John W. Norbury, Michael D. Vera

Faculty Publications

The eikonal, partial wave (PW) Lippmann-Schwinger, and three-dimensional Lippmann-Schwinger (LS3D) methods are compared for nuclear reactions that are relevant for space radiation applications. Numerical convergence of the eikonal method is readily achieved when exact formulas of the optical potential are used for light nuclei (>A≤>16), and the momentum-space representation of the optical potential is used for heavier nuclei. The PW solution method is known to be numerically unstable for systems that require a large number of partial waves, and, as a result, the LS3D method is employed. The effect of relativistic kinematics is studied with the PW and …


Water-Level Changes And Change In Water In Storage In The High Plains Aquifer, Predevelopment To 2013 And 2011-13, Virginia L. Mcguire Dec 2014

Water-Level Changes And Change In Water In Storage In The High Plains Aquifer, Predevelopment To 2013 And 2011-13, Virginia L. Mcguire

United States Geological Survey: Water Reports and Publications

The High Plains aquifer underlies 111.8 million acres (about 175,000 square miles) in parts of eight States—Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. Water-level declines began in parts of the High Plains aquifer soon after the beginning of substantial irrigation with groundwater in the aquifer area (about 1950). This report presents water-level changes in the High Plains aquifer from predevelopment (generally before 1950) to 2013 and from 2011 to 2013. The report also presents change in water in storage in the High Plains aquifer from predevelopment to 2013 and from 2011 to 2013.

The methods to …


Why Is Sea Level Rising In Hampton Roads?, Larry Atkinson, Science Team, Intergovernmental Planning Pilot Project Dec 2014

Why Is Sea Level Rising In Hampton Roads?, Larry Atkinson, Science Team, Intergovernmental Planning Pilot Project

December 2, 2014: Hampton Roads Climate Preparedness and Resilience Exercise Series

No abstract provided.


Getting Down To The Fundamentals Of Hydrogen Bonding: Anharmonic Vibrational Frequencies Of (Hf)2 And (H2o)2 From Ab Initio Electronic Structure Computations, J. Coleman Howard, Jessica L. Gray, Amanda J. Hardwick, Linh T. Nguyen, Gregory S. Tschumper Dec 2014

Getting Down To The Fundamentals Of Hydrogen Bonding: Anharmonic Vibrational Frequencies Of (Hf)2 And (H2o)2 From Ab Initio Electronic Structure Computations, J. Coleman Howard, Jessica L. Gray, Amanda J. Hardwick, Linh T. Nguyen, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

This work presents a systematic investigation into the basis set convergence of harmonic vibrational frequencies of (H2O)2 and (HF)2 computed with second-order Møller-Plesset perturbation theory (MP2) and the coupled-cluster singles and doubles method with perturbative connected triples, CCSD(T), while employing correlation-consistent basis sets as large as aug-cc-pV6Z. The harmonic vibrational frequencies presented here are expected to lie within a few cm-1 of the complete basis set (CBS) limit. For these important hydrogen-bonding prototype systems, a basis set of at least quadruple-ζ quality augmented with diffuse functions is required to obtain harmonic vibrational frequencies within 10 …


Strontium, Lead, And Oxygen Isotopic Signatures Of Mid-Miocene Silicic Volcanism In Eastern Oregon, Emily Nancy Hess Dec 2014

Strontium, Lead, And Oxygen Isotopic Signatures Of Mid-Miocene Silicic Volcanism In Eastern Oregon, Emily Nancy Hess

Dissertations and Theses

Widespread, mid-Miocene rhyolite volcanism of eastern Oregon that are coeval or slightly postdate flood basalts of the Columbia River Basalt Province allows for mapping crustal domains using radiogenic and stable isotopes. Rhyolites are thought to be derived in large part by partial melting of the crust and thus yield direct information on the composition of the crust. Silicic volcanism is expressed in the form of numerous domes and tuffs exposed over a wide area (~300 km in N-S dimension and ~200 km in E-W dimension) west of the presumed craton boundary, which runs parallel but mostly east of the Oregon-Idaho …


Reaction Rates Of Amino Acids With Derivatives Of The Anticancer Drug Cisplatin, Celia Jess Whelan Dec 2014

Reaction Rates Of Amino Acids With Derivatives Of The Anticancer Drug Cisplatin, Celia Jess Whelan

Mahurin Honors College Capstone Experience/Thesis Projects

We are studying reactions of cisplatin derivatives, which differ in both size and shape, with various amino acids. When reaction with DNA occurs, apoptosis is observed, ideally leading to termination of the cancer. Due to the affinity of cisplatin for sulfur-containing amino acids, reaction with proteins may occur prior to access to the DNA, producing a large array of products, which could potentially be toxic to the human body. Both the size and shape of the platinum complexes often affect the reactions with protein targets more so than with DNA targets. By performing reactions of specific amino acids targets with …


Coordination Nature Of 4-Mercaptoaniline To Sn(Ii) Ion: Formation Of A One Dimensional Coordination Polymer And Its Decomposition To A Mono Nuclear Sn(Iv) Complex, Eon S. Burkett, Tasneem A. Siddiquee Dec 2014

Coordination Nature Of 4-Mercaptoaniline To Sn(Ii) Ion: Formation Of A One Dimensional Coordination Polymer And Its Decomposition To A Mono Nuclear Sn(Iv) Complex, Eon S. Burkett, Tasneem A. Siddiquee

Chemistry Faculty Research

The coordination of the bifunctional ligand 4-mercaptoaniline with aqueo us tin(II) metal ion was studied. A coordination polymer was synthesized when an aqueous solution of SnCl2 was treated with 4-MA. The crystalline material is stable under atmospheric conditions retaining its oxidation state. However, when submerged in a solution saturated with oxygen, the compound oxidizes to a mononuclear tin(IV) complex. Both the compounds were characterized by single crystal X-ray diffraction studies. Although the structure of the tin(IV) complex was previously reported, crystal structure of this compound was redetermined.


Cosm News, Georgia Southern University Dec 2014

Cosm News, Georgia Southern University

College of Science & Mathematics: News & Publications (2012-2022)

  • Georgia Southern ROTC Cadet Ranks Fourth in Nation


Nebraska Center For Educational Science Outreach: A Clearinghouse Meeting People At Their Level To Make Stem Outreach Easier, Kiyomi D. Deards Dec 2014

Nebraska Center For Educational Science Outreach: A Clearinghouse Meeting People At Their Level To Make Stem Outreach Easier, Kiyomi D. Deards

University of Nebraska-Lincoln Libraries: Presentations

Identify key partners and stakeholders.

Conduct a STEM outreach needs assessment.

Develop a long-term plan.

1. How can faculty & staff support your STEM outreach?

2. How can you help faculty & staff with STEM outreach?


Chemical And Petrographic Survey Of Large, Igneous-Textured Inclusions In Ordinary Chondrites, Katherine Armstrong Dec 2014

Chemical And Petrographic Survey Of Large, Igneous-Textured Inclusions In Ordinary Chondrites, Katherine Armstrong

Dissertations and Theses

Our inventory of material from the early solar system includes large, igneous-textured inclusions in O chondrites, whose origin and relationship to their host meteorite is unclear. These inclusions occur in approximately 4% of O chondrites, and are mineralogically, petrographically, and chemically diverse. Petrographic and chemical data from 29 inclusions from 23 host meteorites were collected with optical light and scanning electron microscopy, allowing for the determination of major phase modal abundance and major element bulk chemistry. No correlation between any inclusion property and host meteorite type were found, but some trends were observed. Nine of the inclusions show strong evidence, …


Soil Respiration Patterns And Controls In Limestone Cedar Glades, Jennifer Cartwright, Dafeng Hui Dec 2014

Soil Respiration Patterns And Controls In Limestone Cedar Glades, Jennifer Cartwright, Dafeng Hui

Biology Faculty Research

Aims

Drivers of soil respiration (R s ) in rock outcrop ecosystems remain poorly understood. We investigated these drivers in limestone cedar glades, known for their concentrations of endemic plant species and for seasonal hydrologic extremes (xeric and saturated conditions), and compared our findings to those in temperate grasslands and semi-arid ecosystems.

Methods

We measured R s , soil temperature (T s ), volumetric soil water content (SWC), soil organic matter (SOM), soil depth, and vegetation cover monthly over 16 mo and analyzed effects of these variables on R s .

Results

Seasonally, R s primarily tracked T …


Perspectives On Languages For Specifying Simulation Experiments, Luiz Felipe Perrone, Johannes Schützel, Danhua Peng, Adelinde Urhmacher Dec 2014

Perspectives On Languages For Specifying Simulation Experiments, Luiz Felipe Perrone, Johannes Schützel, Danhua Peng, Adelinde Urhmacher

Faculty Journal Articles

While domain specific languages are well established for describing the system of interest in modeling and simulation, the last years have seen increasingly domain specific languages also exploited for specifying experiments. This development, whose application areas range from computational biology to network simulation, is motivated by the desire to facilitate the reproducibility of simulation results. Thereby, the experimentation process is treated as a first class object of simulation studies. As the experimentation process contains different tasks such as configuration, observation, analysis, and evaluation, domain-specific languages can be exploited to specify experiments as well as individual sub-tasks or even the goal …


Data Visualization For Network Simulations, Luiz Felipe Perrone, Greg L. Shrock, Christopher S. Main Dec 2014

Data Visualization For Network Simulations, Luiz Felipe Perrone, Greg L. Shrock, Christopher S. Main

Faculty Journal Articles

As many other kinds of simulation experiments, simulations of computer networks tend to generate high volumes of output data. While the collection and the statistical processing of these data are challenges in and of themselves, creating meaningful visualizations from them is as much an art as it is a science. A sophisticated body of knowledge in information design and data visualization has been developed and continues to evolve. However, many of the visualizations created by the network simulation community tend to be less than optimal at creating compelling, informative narratives from experimental output data. The primary contribution of this paper …


Antimicrobial Properties Of Nano-Silver: A Cautionary Approach To Ionic Interference, Kate Sheehy, Alan Casey, Anna Murphy, Gordon Chambers Dec 2014

Antimicrobial Properties Of Nano-Silver: A Cautionary Approach To Ionic Interference, Kate Sheehy, Alan Casey, Anna Murphy, Gordon Chambers

Articles

Hypothesis: Metallic nanoparticles such as nano-silver have found many applications as alternative antimicrobials in recent years. However methods for determining their proposed antimicrobial activity have received little attention to date. The disk diffusion assay is commonly used as a demonstration of antimicrobial properties and is a regular feature in synthetic nanoparticle papers. The aim of this study was to assess its effectiveness in demonstrating the ‘‘nanoparticle specific’’ antimicrobial properties in the absence of ionic contributions from unreacted reducing agents and or impurities. Experiments: The disk diffusion assay was carried out on a range of silver nanoparticles, both in-house synthesised and …


Differences In The Diversity Of Frogspecies Between Sierra Lloronaand El Valle, Panama, Kei Okabe Thurber Dec 2014

Differences In The Diversity Of Frogspecies Between Sierra Lloronaand El Valle, Panama, Kei Okabe Thurber

Independent Study Project (ISP) Collection

Panama is home to the greatest diversity of species in all of Central America. It is home to 174 species of frogs, 35 of which are endemic to Panama. Frogs are a vital part of many ecosystems. They maintain insect populations and act as food sources for larger predators. Their job of maintaining insect populations is essential to curbing the spread of diseases. Additionally, scientists have found chemical compounds in the skin of frogs that can be used to treat pain and prevent infections. The main threat to the majority of frogs is the deadly fungus Batrachochytrium dendrobatidis (Bd), or …


Frameworks For Nurturing And Assessing Students’ Statistical Thinking In Regression Modelling, Wing Kin, Ken Li Dec 2014

Frameworks For Nurturing And Assessing Students’ Statistical Thinking In Regression Modelling, Wing Kin, Ken Li

Practical Social and Industrial Research Symposium

No abstract provided.


Tvet As An Important Factor In Country’S Economic Development, Margarita Pavlova Dec 2014

Tvet As An Important Factor In Country’S Economic Development, Margarita Pavlova

Practical Social and Industrial Research Symposium

In this keynote speech, Dr Pavlova will bring together a number of strategic development areas for Hong Kong as stated in the 2014 Chief Executive’s Policy Address. These areas include economic development, innovation and technology industries, vocational education and environmental protection.


Improved Upper Limits On The Stochastic Gravitational-Wave Background From 2009-2010 Ligo And Virgo Data, Tiffany Summerscales, Ligo And Virgo Collaboration Dec 2014

Improved Upper Limits On The Stochastic Gravitational-Wave Background From 2009-2010 Ligo And Virgo Data, Tiffany Summerscales, Ligo And Virgo Collaboration

Faculty Publications

Gravitational waves from a variety of sources are predicted to superpose to create a stochastic background. This background is expected to contain unique information from throughout the history of the Universe that is unavailable through standard electromagnetic observations, making its study of fundamental importance to understanding the evolution of the Universe. We carry out a search for the stochastic background with the latest data from the LIGO and Virgo detectors. Consistent with predictions from most stochastic gravitational-wave background models, the data display no evidence of a stochastic gravitational-wave signal. Assuming a gravitational-wave spectrum of ΩGW(f)=Ωα(f/fref)α, we place 95% confidence level …


A Niobium Deposit Hosted By A Magnetite–Dolomite Carbonatite, Elk Creek Carbonatite Complex, Nebraska, Usa, Michael J. Blessington Dec 2014

A Niobium Deposit Hosted By A Magnetite–Dolomite Carbonatite, Elk Creek Carbonatite Complex, Nebraska, Usa, Michael J. Blessington

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The Elk Creek Carbonatite Complex (ECCC) is a large Early Cambrian carbonatite complex that intrudes Precambrian basement rocks in Southeast Nebraska. This dolomitic carbonatite complex includes a magnetite-dolomite rock with accessory barite, ilmenite, rutile, and quartz. This rock is identified by a characteristic enrichment in niobium due to accessory pyrochlore mineralization in the form of disseminations and inclusions in ilmenite and magnetite. Pyrochlore is also present in other carbonatite rocks in the complex as an accessory mineral with sporadic local high-grade intercepts in drill cores.

Carbonatite rock samples are characterized by transmitted-light microscopy, cathodoluminescent microscopy, backscattered electron imaging (BEI), and …


Combating Eutrophication: An Ecosystem Scale Analysis Of Aluminum Sulfate (Alum) Effectiveness Among Lakes, With Comparison To Alum And Biomanipulation Dual Treatment, Christa M. Webber Dec 2014

Combating Eutrophication: An Ecosystem Scale Analysis Of Aluminum Sulfate (Alum) Effectiveness Among Lakes, With Comparison To Alum And Biomanipulation Dual Treatment, Christa M. Webber

School of Natural Resources: Dissertations, Theses, and Student Research

Eutrophic conditions in lakes and reservoirs in agricultural regions often drive summer blooms of toxic cyanobacteria. Aluminum sulfate (alum) applications are commonly used to control cyanobacteria blooms and restore water quality in eutrophic lakes. However, studies of alum treatments often lack true replication, comparison to reference lakes, or comparison to other restoration techniques, such as an alum and biomanipulation combined or “dual” treatments. Without these comparisons, the variation of treatment response between replicate lakes and restoration techniques remains uncertain. Therefore, I sought to assess how water quality is affected by multiple restoration techniques among geographically proximate (1.4 km2) …


Vibrational And Structural Signatures Of The Crossover Between Dense Glassy And Sparse Gel-Like Attractive Colloidal Packings, Matthew A. Lohr, Tim Still, Raman Ganti, Matthew D. Gratale, Zoey S. Davidson, Kevin B. Aptowicz, Carl P. Goodrich, Daniel M. Sussman, A. G. Yodh Dec 2014

Vibrational And Structural Signatures Of The Crossover Between Dense Glassy And Sparse Gel-Like Attractive Colloidal Packings, Matthew A. Lohr, Tim Still, Raman Ganti, Matthew D. Gratale, Zoey S. Davidson, Kevin B. Aptowicz, Carl P. Goodrich, Daniel M. Sussman, A. G. Yodh

Physics & Engineering Faculty Publications

We investigate the vibrational modes of quasi-two-dimensional disordered colloidal packings of hard colloidal spheres with short-range attractions as a function of packing fraction. Certain properties of the vibrational density of states (vDOS) are shown to correlate with the density and structure of the samples (i.e., in sparsely versus densely packed samples). Specifically, a crossover from dense glassy to sparse gel-like states is suggested by an excess of phonon modes at low frequency and by a variation in the slope of the vDOS with frequency at low frequency. This change in phonon mode distribution is demonstrated to arise largely from localized …