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2013

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Articles 151 - 180 of 11461

Full-Text Articles in Physical Sciences and Mathematics

Mitigating Permafrost Degradation Due To Linear Disturbances In Sub-Arctic Peatlands, Aaron A. Mohammed Dec 2013

Mitigating Permafrost Degradation Due To Linear Disturbances In Sub-Arctic Peatlands, Aaron A. Mohammed

Electronic Thesis and Dissertation Repository

The presence or absence of permafrost significantly influences the hydrology and ecology of northern watersheds. Linear disturbances resulting from tree canopy removal have led to widespread permafrost degradation in northern peatlands. Seismic lines resulting from oil and gas exploration now account for large portions of the drainage density of sub-arctic basins, and affect the region’s water and energy balances. As these peatlands represent some of the most sensitive ecosystems to climate and human disturbances, the ability to simulate perturbations to natural systems in a controlled lab environment is particularly important. This study presents a method that is able to simulate …


Potential For Measurement Of Mesospheric Ozone Density From Overdense Meteor Trains With A Monostatic Meteor Radar, Reynold E. Sukara Dec 2013

Potential For Measurement Of Mesospheric Ozone Density From Overdense Meteor Trains With A Monostatic Meteor Radar, Reynold E. Sukara

Electronic Thesis and Dissertation Repository

Thermally ablating meteoroids, colliding with the Earth’s atmosphere, leave a high temperature trail containing extremely energetic metallic ions and electrons. A well recognized, but unresolved, anomaly associated with ambipolar diffusion of meteor trains, which is more dominant in overdense meteors, takes place in the initial post-adiabatic train expansion. In this work, a newly proposed mechanism explaining this anomaly involves hyperthermal chemical reactions is presented. Data from the SKiYMET meteor radar system, deployed at latitudinally dispersed locations, were used to determine ozone density in the upper atmosphere by analyzing diffusion of overdense meteor trains. The results obtained in this study are …


Record Linkage, Stasha Ann Bown Larsen Dec 2013

Record Linkage, Stasha Ann Bown Larsen

Theses and Dissertations

This document explains the use of different metrics involved with record linkage. There are two forms of record linkage: deterministic and probabilistic. We will focus on probabilistic record linkage used in merging and updating two databases. Record pairs will be compared using character-based and phonetic-based similarity metrics to determine at what level they match. Performance measures are then calculated and Receiver Operating Characteristic (ROC) curves are formed. Finally, an economic model is applied that returns the optimal tolerance level two databases should use to determine a record pair match in order to maximize profit.


Nonlinear Spectroscopic Investigation Of Adsorption To C-18 Model Stationary Phase, Anthony D. Peterson Dec 2013

Nonlinear Spectroscopic Investigation Of Adsorption To C-18 Model Stationary Phase, Anthony D. Peterson

Theses and Dissertations

Reversed-phase liquid chromatography (RPLC) is a commonly used separation technique in chemistry. Nevertheless, the mechanistic interactions at the molecular level among the eluent, analyte, and the stationary phase are not fully understood. Because of this limited understanding, optimization of the separation must be done experimentally. Learning more about molecular interactions should aid in improving separations. We are currently using second-harmonic generation (SHG) spectroscopy to investigate how analytes adsorb to the surface. SHG is a spectroscopic technique that produces signal only at places of non-isotropic symmetry; this typically occurs at surfaces. SHG can be used to produce surface isotherms of test …


Building Sustainable Societies: Exploring Sustainability Policy And Practice In The Age Of High Consumption, Cindy Isenhour Dec 2013

Building Sustainable Societies: Exploring Sustainability Policy And Practice In The Age Of High Consumption, Cindy Isenhour

Cindy Isenhour

This dissertation is an attempt to examine how humans in wealthy, post-industrial urban contexts understand sustainability and respond to their concerns given their sphere of influence. I focus specifically on sustainable consumption policy and practice in Sweden, where concerns for sustainability and consumer-based responses are strong. This case raises interesting questions about the relative strength of sustainability movements in different cultural and geo-political contexts as well as the specific factors that have motivated the movement toward sustainable living in Sweden.

The data presented here supports the need for multigenic theories of sustainable consumerism. Rather than relying on dominant theories of …


Titanium Oxide Nanotubes: Synthesis, Properties And Applications For Solar Energy Harvesting, Eugen Panaitescu Dec 2013

Titanium Oxide Nanotubes: Synthesis, Properties And Applications For Solar Energy Harvesting, Eugen Panaitescu

Eugen Panaitescu

Titanium oxide (titania) nanotubes, although relatively recently discovered (less than 15 years ago), have already shown great promise regarding solar energy harvesting applications, exhibiting very good photocatalytic and photovoltaic properties. An alternative anodization route for production of titania nanotubes at the surface of a titanium foil using chloride ions as catalyst instead of the routinely used highly toxic fluorides, is presented in this work. Moreover, the fabrication parameters are extensively studied, thus providing both an insight into the synthesis mechanism and hints towards possible process optimization routes. Although not forming uniformly over the sample surface and lacking long range ordering, …


Structure And Dynamics Of Self-Assembling Colloidal Monolayers In Oscillating Magnetic Fields, Alison E. Patteson (Koser), Nathan C. Keim, Paulo E. Arratia Dec 2013

Structure And Dynamics Of Self-Assembling Colloidal Monolayers In Oscillating Magnetic Fields, Alison E. Patteson (Koser), Nathan C. Keim, Paulo E. Arratia

Physics - All Scholarship

Many fascinating phenomena such as large-scale collective flows, enhanced fluid mixing, and pattern formation have been observed in so-called active fluids, which are composed of particles that can absorb energy and dissipate it into the fluid medium. For active particles immersed in liquids, fluid-mediated viscous stresses can play an important role on the emergence of collective behavior. Here, we experimentally investigate their role in the dynamics of self-assembling magnetically driven colloidal particles which can rapidly form organized hexagonal structures. We find that viscous stresses reduce hexagonal ordering, generate smaller clusters, and significantly decrease the rate of cluster formation, all while …


U.S. Drought Monitor, December 10, 2013, Michael J. Brewer Dec 2013

U.S. Drought Monitor, December 10, 2013, Michael J. Brewer

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for December 10, 2013 (12/10/13) 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.


Fluorination Of Aromatic Ring Systems, Stephen G. Dimagno Dec 2013

Fluorination Of Aromatic Ring Systems, Stephen G. Dimagno

Chemistry Department: Faculty Publications

This disclosure relates to reagents and methods useful in the synthesis of aryl fluorides, for example, in the preparation of 18F labeled radiotracers. The reagents and methods provided herein may be used to access a broad range of compounds, including aromatic compounds, heteroaromatic compounds, amino acids, nucleotides, and synthetic compounds.


Optical Spectroscopic Studies Of Two Star Forming Regions, Kristen Leilani Erickson Dec 2013

Optical Spectroscopic Studies Of Two Star Forming Regions, Kristen Leilani Erickson

Dissertations

The ρ Ophiuchi and Serpens molecular clouds are sites of low mass star formation. The goals of this study were to identify young stellar objects (YSOs) and estimate ages and masses in order to infer an initial mass function (IMF), investigate disk evolution, and determine the star-forming history. Optical spectroscopic surveys of an unbiased sample of candidate young stars have been completed. Optical images taken in different photometric bands were used to create color-magnitude diagrams from which sources were selected for spectroscopic observation. In combination with published data, 135 association members in ρ Ophiuchi and 63 association members plus 16 …


Judy Reservoir Monitoring Project 2013 Final Report, Robin A. Matthews, Joan Vandersypen Dec 2013

Judy Reservoir Monitoring Project 2013 Final Report, Robin A. Matthews, Joan Vandersypen

Judy Reservoir

The purpose of this study was to identify and count the phytoplankton and measure chlorophyll, total nitrogen, and total phosphorus levels in water samples collected from Judy Reservoir. Water quality and algal data have been collected on a weekly basis since October 2006; annual reports have been sent to the Skagit Public Utility District No. 1 in 2007, 2008, 2010 (January and December), 2011, and 2012. This project ended in 2013; the final chemistry sample was collected May 2, 2013 and the final algae sample was collected November 6, 2013.


Capillary Channel Flow Experiments Aboard The International Space Station, Michael Conrath, P. J. Canfield, P. M. Bronowicki, Michael E. Dreyer, Mark M. Weislogel, A. Grah Dec 2013

Capillary Channel Flow Experiments Aboard The International Space Station, Michael Conrath, P. J. Canfield, P. M. Bronowicki, Michael E. Dreyer, Mark M. Weislogel, A. Grah

Mechanical and Materials Engineering Faculty Publications and Presentations

In the near-weightless environment of orbiting spacecraft capillary forces dominate interfacial flow phenomena over unearthly large length scales. In current experiments aboard the International Space Station, partially open channels are being investigated to determine critical flow rate-limiting conditions above which the free surface collapses ingesting bubbles. Without the natural passive phase separating qualities of buoyancy, such ingested bubbles can in turn wreak havoc on the fluid transport systems of spacecraft. The flow channels under investigation represent geometric families of conduits with applications to liquid propellant acquisition, thermal fluids circulation, and water processing for life support. Present and near future experiments …


High Peaks Back - Country Trails Plan, Benjamin Godsoe Dec 2013

High Peaks Back - Country Trails Plan, Benjamin Godsoe

Muskie School Capstones and Dissertations

The High Peaks Trails Plan is a regional vision for back-country trails in Maine's High Peaks region. The plan identifies challenges and opportunities which face the trails community, and outlines several strategies for trails groups to move forward together to overcome mutual challenges.


Photoacoustic And Nephelometric Spectroscopy Of Aerosol Optical Properties With A Supercontinuum Light Source, Neha Sharma, I. J. Arnold, H. Moosmüller, W. P. Arnott, C. Mazzoleni Dec 2013

Photoacoustic And Nephelometric Spectroscopy Of Aerosol Optical Properties With A Supercontinuum Light Source, Neha Sharma, I. J. Arnold, H. Moosmüller, W. P. Arnott, C. Mazzoleni

Michigan Tech Publications

A novel multi-wavelength photoacousticnephelometer spectrometer (SC-PNS) has been developed for the optical characterization of atmospheric aerosol particles. This instrument integrates a white light supercontinuum laser with photoacoustic and nephelometric spectroscopy to measure aerosol absorption and scattering coefficients at five wavelength bands (centered at 417, 475, 542, 607, and 675 nm). These wavelength bands are selected from the continuous spectrum of the laser (ranging from 400-2200 nm) using a set of optical interference filters. Absorption and scattering measurements on laboratory-generated aerosol samples were performed sequentially at each wavelength band. To test the instrument we measured the wavelength dependence of absorption and …


Synthesis, Characterization, And Functionalization Of Magnetic Iron Nanoparticles For Enhanced Biological Applications, Christopher Warren Dec 2013

Synthesis, Characterization, And Functionalization Of Magnetic Iron Nanoparticles For Enhanced Biological Applications, Christopher Warren

Theses and Dissertations

The transition metal ferrites of composition MFe2O4 where M is Fe, Co, or Ni are well established materials for various biological applications due to their interesting magnetic properties. Their elemental and stochiometric composition can be easily manipulated which allows further tuning of their ferrimagnetic properties. By changing the identity of M and by changing the crystallite size of the ferrites, nanocrystals with diverse magnetic properties can be systematically produced. Furthermore, ferrites are more stable in diverse chemical environments, as compared to metallic nanoparticles, which make ferrites particularly useful for a broad range of biomedical applications, especially in the field of …


Uncovering The Deeply Embedded Active Galactic Nucleus Activity In The Nuclear Regions Of The Interacting Galaxy Arp 299, A Alonso-Herrero, Eric S. Perlman Dec 2013

Uncovering The Deeply Embedded Active Galactic Nucleus Activity In The Nuclear Regions Of The Interacting Galaxy Arp 299, A Alonso-Herrero, Eric S. Perlman

Aerospace, Physics, and Space Science Faculty Publications

We present mid-infrared (MIR) 8-13 μm spectroscopy of the nuclear regions of the interacting galaxy Arp 299 (IC 694+NGC 3690) obtained with CanariCam (CC) on the 10.4 m Gran Telescopio Canarias (GTC). The high angular resolution (∼0.″3-0.″6) of the data allows us to probe nuclear physical scales between 60 and 120 pc, which is a factor of 10 improvement over previous MIR spectroscopic observations of this system. The GTC/CC spectroscopy displays evidence of deeply embedded active galactic nucleus (AGN) activity in both nuclei. The GTC/CC nuclear spectrum of NGC 3690/Arp 299-B1 can be explained as emission from AGN-heated dust in …


Accelerating Computational Algorithms, Michael Risley Dec 2013

Accelerating Computational Algorithms, Michael Risley

Theses and Dissertations

Mathematicians and computational scientists are often limited in their ability to model complex phenomena by the time it takes to run simulations. This thesis will inform interested researchers on how the development of highly parallel computer graphics hardware and the compiler frameworks to exploit it are expanding the range of algorithms that can be explored on affordable commodity hardware. We will discuss the complexities that have prevented researchers from exploiting advanced hardware as well as the obstacles that remain for the non-computer scientist.


Environmental And Socio-Economic Considerations For Aquaculture In Jervis Bay, Nsw, Alyssa Joyce, Ana M. Rubio, Pia C. Winberg Dec 2013

Environmental And Socio-Economic Considerations For Aquaculture In Jervis Bay, Nsw, Alyssa Joyce, Ana M. Rubio, Pia C. Winberg

Dr Pia C Winberg

No abstract provided.


Giant Interlayer Magnetoresistances And Strong Anisotropy In P-Type Sb2te3 Single Crystals, Zengji Yue, Xiaolin Wang, S Dou Dec 2013

Giant Interlayer Magnetoresistances And Strong Anisotropy In P-Type Sb2te3 Single Crystals, Zengji Yue, Xiaolin Wang, S Dou

Zengji Yue

Anisotropic interlayer magneto-transport properties have been studied over a broad range of temperatures and magnetic fields in p-type Sb2Te3 single crystals. Giant interlayer magnetoresistance (MR) of up to 400% was observed, which exhibits quadratic field dependences in low fields and becomes linear at high fields without any trend towards saturation. The interlayer MR displays strong anisotropy and is attributable to the anisotropy of the Fermi surface. The observed giant anisotropic interlayer MR could find applications in p-type Sb2Te3 based magneto-electronic devices.


Comparative Water Quality Of Cozine, Gooseneck And Mill Creeks, Shelby Hollenbeck, Emily Isaac, Suzannah Klaniecki, Zach Lea, Meghan Lockwood, Xavier Reed Dec 2013

Comparative Water Quality Of Cozine, Gooseneck And Mill Creeks, Shelby Hollenbeck, Emily Isaac, Suzannah Klaniecki, Zach Lea, Meghan Lockwood, Xavier Reed

Papers from ENVS 385 (Research Methods in Environmental Science)

The environmental research methods class of fall 2013 analyzed the water quality of three creeks in the Yamhill (Oregon) Watershed: Cozine, Gooseneck, and Mill Creeks. Our research builds on data collected by previous years' classes (Colahan et al. 2011; Weinbender and Crane 2011; Bailey et al. 2012). The goals of the project were to gain a better understanding of water quality at each site, see how the sites differ, determine causes for any differences, and examine changes in water quality over time. Because Cozine is surrounded by an urban environment, whereas both Gooseneck and Mill are in a rural setting, …


2013 Fall Engr333 Student Seminar Presentation, Claire Philippi, Karl Bratt, Mike Houtman, Brandon Koster Dec 2013

2013 Fall Engr333 Student Seminar Presentation, Claire Philippi, Karl Bratt, Mike Houtman, Brandon Koster

ENGR 333

File for student presentation, given by students in the Fall 2013 class of ENGR333.


Multi-Column Multi-Layer Computational Model Of Neocortex, Beata Strack Dec 2013

Multi-Column Multi-Layer Computational Model Of Neocortex, Beata Strack

Theses and Dissertations

We present a multi-layer multi-column computational model of neocortex that is built based on the activity and connections of known neuronal cell types and includes activity-dependent short term plasticity. This model, a network of spiking neurons, is validated by showing that it exhibits activity close to biology in terms of several characteristics: (1) proper laminar flow of activity; (2) columnar organization with focality of inputs; (3) low-threshold-spiking (LTS) and fast-spiking (FS) neurons function as observed in normal cortical circuits; and (4) different stages of epileptiform activity can be obtained with either increasing the level of inhibitory blockade, or simulation of …


Analysis Of Mathematical Models Of The Human Lung, Cooper Racheal Dec 2013

Analysis Of Mathematical Models Of The Human Lung, Cooper Racheal

Theses and Dissertations

The processes of lung ventilation and perfusion, diffusion, and gas transport make up the system of breathing and tissue oxygenation. Here, we present several mathematical formulations of the essential processes that contribute to breathing. These models aid in our understanding and analysis of this complex system and can be used to form treatments for patients on ventilators. With the right analysis and treatment options, patients can be helped and money can be saved. We conclude with the formulation of a mathematical model for the exchange of gasses in the body based on basic reaction kinetics.


Mathematical Model Of Dynamic Protein Interactions Regulating P53 Protein Stability For Tumor Suppression, Hua Wang, Guang Peng Dec 2013

Mathematical Model Of Dynamic Protein Interactions Regulating P53 Protein Stability For Tumor Suppression, Hua Wang, Guang Peng

Department of Mathematical Sciences Faculty Publications

In the field of cancer biology, numerous genes or proteins form extremely complex regulatory network, which determines cancer cell fate and cancer cell survival. p53 is a major tumor suppressor that is lost in more than 50% of human cancers. It has been well known that a variety of proteins regulate its protein stability, which is essential for its tumor suppressive function. It remains elusive how we could understand and target p53 stabilization process through network analysis. In this paper we discuss the use of random walk and stationary distribution to measure the compound effect of a network of genes …


Rigidity And Flexibility Of Protein-Nucleic Acid Complexes, Emily Flynn, Filip Jagodzinski, Sharon Pamela Santana, Ileana Streinu Dec 2013

Rigidity And Flexibility Of Protein-Nucleic Acid Complexes, Emily Flynn, Filip Jagodzinski, Sharon Pamela Santana, Ileana Streinu

Computer Science: Faculty Publications

The study of protein-nucleic acid complexes is relevant for the understanding of many biological processes, including transcription, translation, replication, and recombination. The individual molecules in such complexes must be rigid enough to allow geometric matching of complementary shapes, yet sufficiently flexible to perform their functions. © 2013 IEEE.


Asymptotic Theory For Garch-In-Mean Models, Weiwei Liu Dec 2013

Asymptotic Theory For Garch-In-Mean Models, Weiwei Liu

Electronic Thesis and Dissertation Repository

The GARCH-in-mean process is an important extension of the standard GARCH (generalized autoregressive conditional heteroscedastic) process and it has wide applications in economics and finance. The parameter estimation of GARCH type models usually involves the quasi-maximum likelihood (QML) technique as it produces consistent and asymptotically Gaussian distributed estimators under certain regularity conditions. For a pure GARCH model, such conditions were already found with asymptotic properties of its QML estimator well understood. However, when it comes to GARCH-in-mean models those properties are still largely unknown. The focus of this work is to establish a set of conditions under which the QML …


Universal Quantum Fluctuations Of A Cavity Mode Driven By A Josephson Junction, A. D. Armour, M. P. Blencowe, E. Brahimi, A. J. Rimberg Dec 2013

Universal Quantum Fluctuations Of A Cavity Mode Driven By A Josephson Junction, A. D. Armour, M. P. Blencowe, E. Brahimi, A. J. Rimberg

Dartmouth Scholarship

We analyze the quantum dynamics of a superconducting cavity coupled to a voltage-biased Josephson junction. The cavity is strongly excited at resonances where the voltage energy lost by a Cooper pair traversing the circuit is a multiple of the cavity photon energy. We find that the resonances are accompanied by substantial squeezing of the quantum fluctuations of the cavity over a broad range of parameters and are able to identify regimes where the fluctuations in the system take on universal values.


Using Delay-Differential Equations For Modeling Calcium Cycling In Cardiac Myocytes, Ryan Thompson Dec 2013

Using Delay-Differential Equations For Modeling Calcium Cycling In Cardiac Myocytes, Ryan Thompson

Theses

The cycling of calcium at the intracellular level of cardiac cells plays a key role in the excitation-contraction process. The interplay between ionic currents, buffering agents, and calcium release from the sarcoplasmic reticulum (SR) is a complex system that has been shown experimentally to exhibit complex dynamics including period-2 states (alternans) and higher-order rhythms. Many of the calcium cycling activities involve the sensing, binding, or diffusion of calcium between intracellular compartments; these are physical processes that take time and typically are modeled by “relaxation” equations where the steady-state value and time course of a particular variable are specified through an …


Detecting Multilingual Lines Of Text With Fusion Moves, Igor Milevskiy Dec 2013

Detecting Multilingual Lines Of Text With Fusion Moves, Igor Milevskiy

Electronic Thesis and Dissertation Repository

This thesis proposes an optimization-based algorithm for detecting lines of text in images taken by hand-held cameras. The majority of existing methods for this problem assume alphabet-based texts (e.g. in Latin or Greek) and they use heuristics specific to such texts: proximity between letters within one line, larger distance between separate lines, etc. We are interested in a more challenging problem where images combine alphabet and logographic characters from multiple languages where typographic rules vary a lot (e.g. English, Korean, and Chinese). Significantly higher complexity of fitting multiple lines of text in different languages calls for an energy-based formulation combining …


Digital Outcrop Model And Paleoecology Of The Eight-Foot Rapid Algal Field (Middle Pennsylvanian Lower Ismay Sequence), Paradox Basin, Utah, Colton Lynn Goodrich Dec 2013

Digital Outcrop Model And Paleoecology Of The Eight-Foot Rapid Algal Field (Middle Pennsylvanian Lower Ismay Sequence), Paradox Basin, Utah, Colton Lynn Goodrich

Theses and Dissertations

Although phylloid algal mounds have been studied for 50 year, much remains to be determined concerning the ecology and sedimentology of these Late Paleozoic carbonate buildups. Herein we perform a digital outcrop study of the well-known Middle Pennsylvanian Lower Ismay mound interval in the Paradox Basin because outcropping mounds along the San Juan River are cited as outcrop analogs of reservoir carbonates in the Paradox Basin oil province of Utah and adjacent states. The principal field area is the Eight Foot algal field located at river mile 19.2 on the San Juan River, approximately 14 miles SSW of Bluff, Utah. …