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Articles 145831 - 145860 of 302566

Full-Text Articles in Physical Sciences and Mathematics

Observations Of Fire-Induced Turbulence Regimes During Low-Intensity Wildland Fires In Forested Environments: Implications For Smoke Dispersion, Warren Heilman, Craig Clements, Daisuke Seto, Xindi Bian, Kenneth Clark, Nicholas Skowronski, John Hom Jan 2015

Observations Of Fire-Induced Turbulence Regimes During Low-Intensity Wildland Fires In Forested Environments: Implications For Smoke Dispersion, Warren Heilman, Craig Clements, Daisuke Seto, Xindi Bian, Kenneth Clark, Nicholas Skowronski, John Hom

Faculty Publications, Meteorology and Climate Science

Low-intensity wildland fires occurring beneath forest canopies can result in particularly adverse local air-quality conditions. Ambient and fire-induced turbulent circulations play a substantial role in the transport and dispersion of smoke during these fire events. Recent in situ measurements of fire–atmosphere interactions during low-intensity wildland fires have provided new insight into the structure of fire-induced turbulence regimes and how forest overstory vegetation can affect the horizontal and vertical dispersion of smoke. In this paper, we provide a summary of the key turbulence observations made during two low-intensity wildland fire events that occurred in the New Jersey Pine Barrens.


The Sluggs Survey: Globular Cluster Stellar Population Trends From Weak Absorption Lines In Stacked Spectra, Christopher Usher, Duncan Forbes, Jean Brodie, Aaron Romanowsky, Jay Strader, Charlie Conroy, Caroline Foster, Nicola Pastorello, Vincenzo Pota, Jacob Arnold Jan 2015

The Sluggs Survey: Globular Cluster Stellar Population Trends From Weak Absorption Lines In Stacked Spectra, Christopher Usher, Duncan Forbes, Jean Brodie, Aaron Romanowsky, Jay Strader, Charlie Conroy, Caroline Foster, Nicola Pastorello, Vincenzo Pota, Jacob Arnold

Faculty Publications

As part of the SAGES Legacy Unifying Globulars and GalaxieS (SLUGGS) survey, we stack 1137 Keck DEIMOS (Deep Imaging Multi-Object Spectrograph) spectra of globular clusters from 10 galaxies to study their stellar populations in detail. The stacked spectra have median signal-to-noise ratios of ∼90 Å−1. Besides the calcium triplet, we study weaker sodium, magnesium, titanium and iron lines as well as the Hα and higher order Paschen hydrogen lines. In general, the stacked spectra are consistent with old ages and a Milky Way-like initial mass function. However, we see different metal line index strengths at fixed colour and magnitude, and …


Finite-Temperature Superconducting Correlations Of The Hubbard Model, Ehsan Khatami, Richard Scalettar, Rajiv Singh Jan 2015

Finite-Temperature Superconducting Correlations Of The Hubbard Model, Ehsan Khatami, Richard Scalettar, Rajiv Singh

Faculty Publications

We utilize numerical linked-cluster expansions (NLCEs) and the determinantal quantum Monte Carlo algorithm to study pairing correlations in the square-lattice Hubbard model. To benchmark the NLCE, we first locate the finite-temperature phase transition of the attractive model to a superconducting state away from half filling. We then explore the superconducting properties of the repulsive model for the d-wave and extended s-wave pairing symmetries. The pairing structure factor shows a strong tendency to d-wave pairing and peaks at an interaction strength comparable to the bandwidth. The extended s-wave structure factor and correlation length are larger at higher temperatures but clearly saturate …


Spectroscopic Confirmation Of The Existence Of Large, Diffuse Galaxies In The Coma Cluster, Pieter Van Dokkum, Aaron Romanowsky, Roberto Abraham, Jean Brodie, Charlie Conroy, Marla Geha, Allison Merritt, Alexa Villaume, Jielai Zhang Jan 2015

Spectroscopic Confirmation Of The Existence Of Large, Diffuse Galaxies In The Coma Cluster, Pieter Van Dokkum, Aaron Romanowsky, Roberto Abraham, Jean Brodie, Charlie Conroy, Marla Geha, Allison Merritt, Alexa Villaume, Jielai Zhang

Faculty Publications

No abstract provided.


Small Scatter And Nearly Isothermal Mass Profiles To Four Half-Light Radii From Two-Dimensional Stellar Dynamics Of Early-Type Galaxies, Michele Cappellari, Aaron Romanowsky, Jean Brodie, Duncan Forbes, Jay Strader, Caroline Foster, Sreeja Kartha, Nicola Pastorello, Vincenzo Pota, Lee Spitler, Christopher Usher, Jacob Arnold Jan 2015

Small Scatter And Nearly Isothermal Mass Profiles To Four Half-Light Radii From Two-Dimensional Stellar Dynamics Of Early-Type Galaxies, Michele Cappellari, Aaron Romanowsky, Jean Brodie, Duncan Forbes, Jay Strader, Caroline Foster, Sreeja Kartha, Nicola Pastorello, Vincenzo Pota, Lee Spitler, Christopher Usher, Jacob Arnold

Faculty Publications

No abstract provided.


Ngc 3628-Ucd1: A Possible Ω Cen Analog Embedded In A Stellar Stream, Zachary Jennings, Aaron Romanowsky, Jean Brodie, Joachim Janz, Mark Norris, Duncan Forbes, David Martinez-Delgado, Martina Fagioli, Samantha Penny Jan 2015

Ngc 3628-Ucd1: A Possible Ω Cen Analog Embedded In A Stellar Stream, Zachary Jennings, Aaron Romanowsky, Jean Brodie, Joachim Janz, Mark Norris, Duncan Forbes, David Martinez-Delgado, Martina Fagioli, Samantha Penny

Faculty Publications

No abstract provided.


The Digital Atlas Of Ancient Life: Delivering Information On Paleontology And Biogeography, Jonathan R. Hendricks, Alycia L. Stigall, Bruce S. Lieberman Jan 2015

The Digital Atlas Of Ancient Life: Delivering Information On Paleontology And Biogeography, Jonathan R. Hendricks, Alycia L. Stigall, Bruce S. Lieberman

Faculty Publications

No abstract provided.


Review Of Lifeblood: Oil, Freedom, And The Forces Of Capital, Dustin Mulvaney Jan 2015

Review Of Lifeblood: Oil, Freedom, And The Forces Of Capital, Dustin Mulvaney

Faculty Publications, Environmental Studies

A review of Lifeblood: oil, freedom, and the forces of capital, by Matthew T. Huber, Minneapolis, University of Minnesota Press, 2013, 253 pp., $25 (paperback), ISBN 978-0-8166-7785-6


Analyzing Free-Base Nicotine Content In The Particulate Matter Of Mainstream Tobacco Smoke Using A Headpace Solid-Phase Microextraction Gc/Ms Method, Christopher S. Motti Jan 2015

Analyzing Free-Base Nicotine Content In The Particulate Matter Of Mainstream Tobacco Smoke Using A Headpace Solid-Phase Microextraction Gc/Ms Method, Christopher S. Motti

Civil and Environmental Engineering Master's Project Reports

The acid/base chemistry of cigarette smoke allows nicotine, the primary drug in mainstream tobacco smoke, to exist in protonated and free-base forms. Evidence suggests that most of the nicotine present in mainstream tobacco smoke is in the particle phase. αfb is the fraction of particle-phase nicotine in the free-base form. The magnitude and rate of nicotine deposition in the respiratory tract is dependent on αfb because only the free-base form of nicotine can volatilize from the particle phase of an inhaled aerosol and, once gaseous, rapidly deposit. This study develops a headspace solid-phase microextraction technique coupled with gas …


Geotechnical Statistical Evaluation Of Lahore Site Data And Deep Excavation Design, Aiza Malik Jan 2015

Geotechnical Statistical Evaluation Of Lahore Site Data And Deep Excavation Design, Aiza Malik

Civil and Environmental Engineering Master's Project Reports

Geotechnical characterization for foundation design is critical during preliminary planning, designing and feasibility studies of various engineering projects. In this research, an effort has been made to develop a geotechnical database for the city of Lahore, Pakistan. This database would aid geologists and engineers involved in the geotechnical design and planning of engineering projects in Lahore. The project area has been divided into zones geographically. Soil profiles have been developed for all zones, which provide ranges of soil properties and SPT-N values at regular intervals. Furthermore, the research also focuses on deep excavations in urban areas of Lahore, Pakistan and …


What Is Valuable?, Kelly Harer Jan 2015

What Is Valuable?, Kelly Harer

SR & SC Masters Projects

No abstract provided.


Turning Toward Feeling, Elizabeth D. Mcgrew Jan 2015

Turning Toward Feeling, Elizabeth D. Mcgrew

SR & SC Masters Projects

Five years ago, upon completing a 200-hour, 30-day intensive yoga teacher-training course, we took this group photo. Painted on the wall behind us are the words, “Feel pain? Change positions.” At that time in my life, my understanding of this assertion was shallow: if it feels as though something is ripping, pulling, or tearing, move out of the yoga pose. But as for other physical and emotional pain, I had been taught to sit with it and accept it, and by doing so I would demonstrate strength and continue to grow stronger. Turning away from pain seemed cowardly. It wasn’t …


2015 Sustainability Report [Western Kentucky University], Wku Office Of Sustainability, Christian Ryan-Downing Jan 2015

2015 Sustainability Report [Western Kentucky University], Wku Office Of Sustainability, Christian Ryan-Downing

Sustainability Publications and Resources

2015 was a great year for WKU Sustainability, marked by significant new initiatives, special recognitions, and continued progress in advancing sustainability in the way Hilltoppers live, learn, and work. This report highlights the sustainability accomplishments of WKU students, faculty, staff, the Office of Sustainability, and the campus community in 2015.


2015 Abstracts Student Research Conference, Student Research Conference Jan 2015

2015 Abstracts Student Research Conference, Student Research Conference

Student Research Conference Select Presentations

No abstract provided.


Properly Colored Notions Of Connectivity - A Dynamic Survey, Xueliang Li, Colton Magnant Jan 2015

Properly Colored Notions Of Connectivity - A Dynamic Survey, Xueliang Li, Colton Magnant

Department of Mathematical Sciences Faculty Publications

Sheehan conjectured in 1975 that every Hamiltonian regular simple graph of even degree at least four contains a second Hamiltonian cycle. We prove that most claw-free Hamiltonian graphs with minimum degree at least 3 have a second Hamiltonian cycle and describe the structure of those graphs not covered by our result. By this result, we show that Sheehan’s conjecture holds for claw-free graphs whose order is not divisible by 6. In addition, we believe that the structure that we introduce can be useful for further studies on claw-free graphs.


Friedel–Crafts Hydroxyalkylation Of Indoles Mediated By Trimethylsilyl Trifluoromethanesulfonate, C. Wade Downey, Christopher D. Poff, Alissa N. Nizinski Jan 2015

Friedel–Crafts Hydroxyalkylation Of Indoles Mediated By Trimethylsilyl Trifluoromethanesulfonate, C. Wade Downey, Christopher D. Poff, Alissa N. Nizinski

Chemistry Faculty Publications

Indoles and N-alkylindoles undergo Friedel–Crafts addition to aldehydes in the presence of trimethylsilyl trifluoromethanesulfonate and a trialkylamine to produce 3-(1- silyloxyalkyl)indoles. Neutralization of the reaction mixture with pyridine followed by deprotection under basic conditions with tetrabutylammonium fluoride provides the 1:1 adduct as the free alcohol. This method prevents spontaneous conversion of the desired products to the thermodynamically favored bisindolyl(aryl)methanes, a process typically observed when indoles are reacted with aldehydes under acidic conditions.


Learning To Use, Useful For Learning: A Usability Study Of Google Apps For Education, Maury Elizabeth Brown, Daniel L. Hocutt Jan 2015

Learning To Use, Useful For Learning: A Usability Study Of Google Apps For Education, Maury Elizabeth Brown, Daniel L. Hocutt

School of Professional and Continuing Studies Faculty Publications

Using results from an original survey instrument, this study examined student perceptions of how useful Google Apps for Education (GAFE) was in students' learning of core concepts in a first-year college composition course, how difficult or easy it was for students to interact with GAFE, and how students ranked specific affordances of the technology in terms of its usability and usefulness. Students found GAFE relatively easy to use and appreciated its collaborative affordances. The researchers concluded that GAFE is a useful tool to meet learning objectives in the college composition classroom.


Photocurrent-Voltage Relation Of Resonant Tunneling Diode Photodetectors, Andreas Pfenning, Favbian Hartmann, Mariama Rebello Sousa Dias, Fabian Langer, Martin Kamp, Leonardo Kleber Castelano, Victor Lopez-Richard, Gilmar Eugenio Marques, Sven Höfling, Lukas Worschech Jan 2015

Photocurrent-Voltage Relation Of Resonant Tunneling Diode Photodetectors, Andreas Pfenning, Favbian Hartmann, Mariama Rebello Sousa Dias, Fabian Langer, Martin Kamp, Leonardo Kleber Castelano, Victor Lopez-Richard, Gilmar Eugenio Marques, Sven Höfling, Lukas Worschech

Physics Faculty Publications

We have investigated photodetectors based on an AlGaAs/GaAs double barrier structure with a nearby lattice-matched GaInNAs absorption layer. Photons with the telecommunication wavelength λ = 1.3 µm lead to hole accumulation close to the double barrier inducing a voltage shift ΔV(V) of the current-voltage curve, which depends strongly on the bias voltage V. A model is proposed describing ΔV(V) and the photocurrent response in excellent agreement with the experimental observations. According to the model, an interplay of the resonant tunneling diode (RTD) quantum efficiency ƞ(V), the lifetime of photogenerated …


Santa Clara Magazine, Volume 56 Number 3, Spring/Summer 2015, Santa Clara University Jan 2015

Santa Clara Magazine, Volume 56 Number 3, Spring/Summer 2015, Santa Clara University

Santa Clara Magazine

16 - SILICON VALLEY STORY by Michael S. Malone '75, MBA '77. The hidden history behind the heart of ingenuity.

22 - BARCELONA SIESTA by Maya Kroth '01. On a Fulbright to Spain, in pursuit of the meaning of sleep. In the 21st century, it's not what it used to be. By Maya Kroth '01.

26 - BUILD IT BEAUTIFUL. See how the campus has been transformed in the past two decades-thanks in no small part to Joe Sugg. Illustration by Rod Hunt.

28 - A GOOD BASEBALL MAN by Jeff Gire. Charlie Graham and a tale of the Red …


La Igualdad De Género En Las Carreras De Conservación: Ucayali, Peru En Un Contexto Global, Anna Sangree, Mary Finley-Brook Jan 2015

La Igualdad De Género En Las Carreras De Conservación: Ucayali, Peru En Un Contexto Global, Anna Sangree, Mary Finley-Brook

Geography and the Environment Faculty Publications

Las mujeres aportan las habilidades y las perspectivas importantes para la conservación, pero menos mujeres completan estudios superiores en campos como la silvicultura y la agronomía. Las mujeres que entran en estos campos profesionales también tienen menos oportunidades de alcanzar las posiciones del liderazgo. Las investigaciones internacionales sugieren que muchas veces los esfuerzos hacia la sostenibilidad son perjudicados por los bajos niveles de participación de las mujeres y la falta del liderazgo femenino. Este estudio conecta los resultados de una revisión de la literatura internacional con experiencias personales de los estudiantes, los docentes, y los administradores en la Universidad Nacional …


Modeling Network Worm Outbreaks, Evan Foley Jan 2015

Modeling Network Worm Outbreaks, Evan Foley

Electronic Theses and Dissertations

Due to their convenience, computers have become a standard in society and therefore, need the utmost care. It is convenient and useful to model the behavior of digital virus outbreaks that occur, globally or locally. Compartmental models will be used to analyze the mannerisms and behaviors of computer malware. This paper will focus on a computer worm, a type of malware, spread within a business network. A mathematical model is proposed consisting of four compartments labeled as Susceptible, Infectious, Treatment, and Antidotal. We shall show that allocating resources into treating infectious computers leads to a reduced peak of infections across …


Conservation Laws And Electromagnetic Interactions, Veerachart Kajorndejnukul Jan 2015

Conservation Laws And Electromagnetic Interactions, Veerachart Kajorndejnukul

Electronic Theses and Dissertations

Aside from energy, light carries linear and angular momenta that can be transferred to matter. The interaction between light and matter is governed by conservation laws that can manifest themselves as mechanical effects acting on both matter and light waves. This interaction permits remote, precise, and noninvasive manipulation and sensing at microscopic levels. In this dissertation, we demonstrated for the first time a complete set of opto-mechanical effects that are based on nonconservative forces and act at the interface between dielectric media. Without structuring the light field, forward action is provided by the conventional radiation pressure while a backward movement …


The Safe Removal Of Frozen Air From The Annulus Of A Liquid Hydrogen Storage Tank, Angela Krenn Jan 2015

The Safe Removal Of Frozen Air From The Annulus Of A Liquid Hydrogen Storage Tank, Angela Krenn

Electronic Theses and Dissertations

Large Liquid Hydrogen (LH2) storage tanks are vital infrastructure for NASA. Eventually, air may leak into the evacuated and perlite filled annular region of these tanks. Although the vacuum level is monitored in this region, the extremely cold temperature causes all but the helium and neon constituents of air to freeze. A small, often unnoticeable pressure rise is the result. As the leak persists, the quantity of frozen air increases, as does the thermal conductivity of the insulation system. Consequently, a notable increase in commodity boiloff is often the first indicator of an air leak. Severe damage can then result …


Nanoscale Control Of Gap-Plasmon Enhanced Optical Processes, Chatdanai Lumdee Jan 2015

Nanoscale Control Of Gap-Plasmon Enhanced Optical Processes, Chatdanai Lumdee

Electronic Theses and Dissertations

Surface plasmon resonances of metal nanostructures have been studied intensely in recent years. The strong plasmon-mediated electric field enhancement and field confinement well beyond the diffraction limit has been demonstrated to improve the performance of optical devices including ultrasensitive sensors, light emitters, and optical absorbers. A plasmon resonance mode of particular recent interest is the gap plasmon resonance that occurs on closely spaced metallic structures. In contrast to plasmon resonances supported by isolated metal nanostructures, coupled nanostructures provide additional spectral and spatial control over the plasmon resonance response. For example, the resonance frequencies of metal nanoparticle dimers depend strongly on …


Photon Statistics In Disordered Lattices, Hasan Kondakci Jan 2015

Photon Statistics In Disordered Lattices, Hasan Kondakci

Electronic Theses and Dissertations

Propagation of coherent waves through disordered media, whether optical, acoustic, or radio waves, results in a spatially redistributed random intensity pattern known as speckle -- a statistical phenomenon. The subject of this dissertation is the statistics of monochromatic coherent light traversing disordered photonic lattices and its dependence on the disorder class, the level of disorder and the excitation configuration at the input. Throughout the dissertation, two disorder classes are considered, namely, diagonal and off-diagonal disorders. The latter exhibits disorder-immune chiral symmetry -- the appearance of the eigenmodes in skew-symmetric pairs and the corresponding eigenvalues in opposite signs. When a disordered …


Optimization Of Molecular Beacon-Based Multicomponent Probes For Analysis Of Nucleic Acids, Maria Stancescu Jan 2015

Optimization Of Molecular Beacon-Based Multicomponent Probes For Analysis Of Nucleic Acids, Maria Stancescu

Electronic Theses and Dissertations

Detection of single nucleotide substitutions (SNS) in DNA and RNA has a growing importance in biology and medicine. One traditional approach for recognition of SNS takes advantage of hybridization probes that bind target nucleic acids followed by measuring ?Tm, the difference in melting temperatures of matched and mismatched hybrids. The approach enables SNS differentiation at elevated temperatures (usually 40-65oC) often only in a narrow range of < 10oC and requires high-resolution melting devices. Here we demonstrate that a specially designed DNA probe (X sensor) can broaden ?Tm from ~10oC to ~16oC and distinguish SNS in the interval of ~5-40oC. Therefore, there is no need for heating or measuring Tm for accurate SNS differentiation. Our data indicate that this wide differentiation range is in part due to the non-equilibrium hybridization conditions. Further we explored the idea that it is possible to improve the performance of an X sensor operable in close to equilibrium conditions by shifting its operability to non-equilibrium conditions. One way to achieve this is to introduce as many as possible structured ligands in analyte's dissociated state. Here we show that by introducing the maximum possible conformational constraints in X probe it is possible to shift its operation to non-equilibrium conditions and to improve its selectivity at temperatures < 15oC. Thus, this work points towards a new strategy for the design of highly selective hybridization sensors which operate in non-equilibrium conditions at close to room temperature. The X sensors could be utilized in qPCR, microarrays, as well as RNA analysis in living cells and for ambient temperature point-of-care diagnostics. In the last part of this work, X sensors were used in real time detection of PCR products. The sensors were optimized to operate in PCR buffer with optimal Mg2+ concentration. They were able to detect the target amplicon together with nonspecific products. The results presented here suggest that X sensors might be adopted for real time PCR format.


Synthesis, Linear And Nonlinear Photophysical Characterization Of Two Symmetrical Pyrene-Terminated Squaraine Derivatives In Solution, Alfonso Ballestas Barrientos Jan 2015

Synthesis, Linear And Nonlinear Photophysical Characterization Of Two Symmetrical Pyrene-Terminated Squaraine Derivatives In Solution, Alfonso Ballestas Barrientos

Electronic Theses and Dissertations

Two indole-based squaraine dyes bonded to two pyrenyl groups through vinyl- and ethynyl- linkers were synthesized with the aim of enhancing the intramolecular charge transfer interaction in addition to improving their optical properties. The absorption and emission properties of these derivatives were determined in order to gain an insight into the intensity of this type of interaction, their aggregation behavior and compare them with results obtained through quantum chemical calculations. Both compounds presented high photochemical stability in THF, and the linear spectroscopic characterization revealed high extinction coefficients, large fluorescence quantum yields and relatively low tendency of forming excimers in several …


Strategies For Enhanced Genetic Analysis Of Trace Dna From Touch Dna Evidence And Household Dust, Katherine Farash Jan 2015

Strategies For Enhanced Genetic Analysis Of Trace Dna From Touch Dna Evidence And Household Dust, Katherine Farash

Electronic Theses and Dissertations

In forensic casework it is often necessary to obtain genetic profiles from crime scene samples that contain increasingly smaller amounts of genetic material, called Low Template DNA (LTDNA). Two examples of LTDNA sources are touch DNA evidence and dust bunnies. Touch DNA refers to DNA that is left behind through casual contact of a donor with an object or another person. Touch DNA can be used to prove a suspect was present at a crime scene. Dust bunnies, or dust conglomerates, typically contain trapped shed skin cells of anyone in the vicinity along with fibers, dirt, hair, and other trace …


Investigating New Guaiazulenes And Diketopyrropyrroles For Photonic Applications, Ebrahim Ghazvini Zadeh Jan 2015

Investigating New Guaiazulenes And Diketopyrropyrroles For Photonic Applications, Ebrahim Ghazvini Zadeh

Electronic Theses and Dissertations

?-Conjugated systems have been the focus of study in recent years in order to understand their charge transport and optical properties for use in organic electronic devices, fluorescence bioimaging, sensors, and 3D optical data storage (ODS), among others. As a result, several molecular building blocks have been designed, allowing new frontiers to be realized. While various successful building blocks have been fine-tuned at both the electronic and molecular structure level to provide advanced photophysical and optoelectronic characteristics, the azulene framework has been under-appreciated despite its unique electronic and optical properties. Among several attributes, azulenes are vibrant blue naturally occurring hydrocarbons …


Nanoelectronic Devices Using Carbon Nanotubes And Graphene Electrodes: Fabrication And Electronic Transport Investigations, Narae Kang Jan 2015

Nanoelectronic Devices Using Carbon Nanotubes And Graphene Electrodes: Fabrication And Electronic Transport Investigations, Narae Kang

Electronic Theses and Dissertations

Fabrication of high-performance electronic devices using the novel semiconductors is essential for developing future electronics which can be applicable in large-area, flexible and transparent displays, sensors and solar cells. One of the major bottlenecks in the fabrication of high-performance devices is a large interfacial barrier formation at metal/semiconductor interface originated from Schottky barrier and interfacial dipole barrier which causes inefficient charge injection at the interface. Therefore, having a favorable contact at electrode/semiconductor is highly desirable for high-performance devices fabrication. In this dissertation, the fabrication of nanoelectronic devices and investigation of their transport properties using carbon nanotubes (CNTs) and graphene as …