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Talif Investigation And Modelling Of The Absolute N(4s) Density In A N2-Ch4 Late Afterglow, C.D. Pintassilgo, Et. Es-sebbar, Y. Benilan, M-C. Gazeau, A. Jolly 2010 Paul Scherrer Institute (PSI)

Talif Investigation And Modelling Of The Absolute N(4s) Density In A N2-Ch4 Late Afterglow, C.D. Pintassilgo, Et. Es-Sebbar, Y. Benilan, M-C. Gazeau, A. Jolly

Dr. Et-touhami Es-sebbar

The purpose of the present work is the experimental and numerical study of the absolute ground-state nitrogen atoms density N(4S) in the late afterglow of a pure N2 flowing microwave discharge in which different amounts of CH4 have been injected at 25 cm downstream from the nitrogen discharge. The absolute N(4S) concentrations have been measured using Two-photon Absorption Laser-Induced Fluorescence (TALIF), while a detailed kinetic model has been developed to simulate both the discharge and the post-discharge regions. Theoretical predictions are then compared to experimental measurements.


Core-Shell Nanoparticles: Synthesis, Design, And Characterization, Kyler Carroll 2010 Virginia Commonwealth University

Core-Shell Nanoparticles: Synthesis, Design, And Characterization, Kyler Carroll

Theses and Dissertations

The design of core/shell nanoparticles is of great interest for a wide range of applications. The primary focus of this dissertation is on the design and optimization of two synthetic routes. The first one is an aqueous reduction method using sodium borohydride and sodium citrate. This method was extended to design two types of core/shell nanoparticles, both of which have many applications in bio-sensing, magnetic resonance imaging, and magnetically guided SERS for the identification of environmental threats. The first, Fe/Ag core/shell nanoparticles were designed using a novel one-pot method by varying the AgNO3 addition time ...


The Nature Of The O-2/O-5 Cooperative Effect And Its Role In Chemical Glycosylation, Laurel Kathryn Mydock 2010 University of Missouri-St. Louis

The Nature Of The O-2/O-5 Cooperative Effect And Its Role In Chemical Glycosylation, Laurel Kathryn Mydock

Dissertations

Since carbohydrates were first discovered, understanding the structure, reactivity, and function of these bioorganic compounds has remained of great priority. However, as the appreciation for the biological roles of carbohydrates intensifies, a growing demand for efficient and scalable methods towards the synthesis of these challenging molecules has become even more imperative. While modern synthetic techniques have allowed us to readily achieve most glycosidic linkages, it is the inability to effectively predict and control the stereoselectivity of the glycosylation reaction that has remained the synthetic hurdle. Herein, much effort has been placed in the investigation of “mixed-patterned” glycosyl donors as they ...


Deep-Sea Fishes Of The Mid-Atlantic Ridge: Results Of The 2009 Henry Bigelow Expedition, Tracey Sutton, April B. Cook, John K. Galbraith, M. Vecchione 2010 Virginia Institute of Marine Science

Deep-Sea Fishes Of The Mid-Atlantic Ridge: Results Of The 2009 Henry Bigelow Expedition, Tracey Sutton, April B. Cook, John K. Galbraith, M. Vecchione

Oceanography Faculty Proceedings, Presentations, Speeches, Lectures

As part of an ongoing study of the northern Mid-Atlantic Ridge biodiversity and ecology (CoML field project MAR-ECO), a detailed survey of the pelagic and demersal fishes in the region of the Charlie-Gibbs Fracture Zone (~ 600 n.m. south of Greenland) was conducted. A total of 17181 pelagic fishes (92 spp., 35 families) were sampled from 0-3000+ m, with the Myctophidae the most species-rich. The bristlemouth Cyclothone microdon was by far the dominant species in numbers (82% of total), while the sawtooth eel Serrivomer beani dominated biomass (27%). A total of 441 deep-demersal fishes (28 spp., 13 families) were sampled ...


A Mass-Loss Rate Determination For Zeta Puppis From The Quantitative Analysis Of X-Ray Emission-Line Profiles, David H. Cohen, M. A. Leutenegger, Emma Edwina Wollman , '09, J. Zsargó, D. J. Hillier, R. H.D. Townsend, S. P. Owocki 2010 Swarthmore College

A Mass-Loss Rate Determination For Zeta Puppis From The Quantitative Analysis Of X-Ray Emission-Line Profiles, David H. Cohen, M. A. Leutenegger, Emma Edwina Wollman , '09, J. Zsargó, D. J. Hillier, R. H.D. Townsend, S. P. Owocki

Physics & Astronomy Faculty Works

We fit every emission line in the high-resolution Chandra grating spectrum of. Pup with an empirical line profile model that accounts for the effects of Doppler broadening and attenuation by the bulk wind. For each of 16 lines or line complexes that can be reliably measured, we determine a best-fitting fiducial optical depth, tau(*) equivalent to kappa(M) over dot/4 pi R(*)upsilon(infinity), and place confidence limits on this parameter. These 16 lines include seven that have not previously been reported on in the literature. The extended wavelength range of these lines allows us to infer, for the ...


Stable Isotope Analysis Of The Sandbar Shark, Carcharinus Plumbeus: A Minimally Invasive Method For Comparison Of Diet And Trophic Relationships Between Genders, Locations, And Age Classes, David Shiffman, Gorka Sancho, Bryan Frazier, John Kucklick, Dan Abel, Tracey Sutton, Kristene T. Parsons 2010 College of Charleston

Stable Isotope Analysis Of The Sandbar Shark, Carcharinus Plumbeus: A Minimally Invasive Method For Comparison Of Diet And Trophic Relationships Between Genders, Locations, And Age Classes, David Shiffman, Gorka Sancho, Bryan Frazier, John Kucklick, Dan Abel, Tracey Sutton, Kristene T. Parsons

Oceanography Faculty Proceedings, Presentations, Speeches, Lectures

The 2006 National Marine Fisheries Service SEDAR for large coastal sharks recommended the gathering of additional diet and trophic relationship data for the sandbar shark, Carcharinus plumbeus. No diet studies of any kind have been performed on South Carolina subpopulations of C. plumbeus, and stable isotope analysis has never been performed on this species. Muscle samples were taken from C. plumbeus caught by the South Carolina Department of Natural Resources and the Virginia Institute of Marine Science shark surveys. The analysis of δ13C and δ 15N from this muscle tissue is ongoing and will be compared with prey species and ...


Distribution And Trophic Ecology Of Bathylagus Euryops (Teleostei: Microstomatidae) Along The Northern Mid-Atlantic Ridge, Christopher J. Sweetman, Tracey Sutton 2010 Virginia Institute of Marine Science

Distribution And Trophic Ecology Of Bathylagus Euryops (Teleostei: Microstomatidae) Along The Northern Mid-Atlantic Ridge, Christopher J. Sweetman, Tracey Sutton

Oceanography Faculty Proceedings, Presentations, Speeches, Lectures

The assemblage structure and ecology of meso- and bathypelagic fishes are poorly known in general, particularly over mid-ocean ridges. In June 2004, the month-long MAR-ECO (Census of Marine Life) research expedition aboard the R/V G.O. Sars sampled the deep-pelagic fauna over the northern Mid-Atlantic Ridge with the objective of quantitatively assessing the nekton associated with the ridge from Iceland to the Azores. A total of 115 discrete-depth trawl samples were taken from the surface to depths of 3000+ meters using two different double-warp midwater trawls, one of commercial fishing size (a large ‘Akra' trawl) and one of oceanographic ...


Vanishing Of Ext And Tor Over Complete Intersections, Olgur Celikbas 2010 University of Nebraska-Lincoln

Vanishing Of Ext And Tor Over Complete Intersections, Olgur Celikbas

Dissertations, Theses, and Student Research Papers in Mathematics

Let (R,m) be a local complete intersection, that is, a local ring whose m-adic completion is the quotient of a complete regular local ring by a regular sequence. Let M and N be finitely generated R-modules. This dissertation concerns the vanishing of Tor(M, N) and Ext(M, N). In this context, M satisfies Serre's condition (S_{n}) if and only if M is an nth syzygy. The complexity of M is the least nonnegative integer r such that the nth Betti number of M is bounded by a polynomial of degree r-1 for all sufficiently large n ...


Neuraminidase Activity Of Influenza Virus Strains That Differ In The Ability To Cause Disease, Benjamin Brown, Bart Tarbet 2010 Utah State University

Neuraminidase Activity Of Influenza Virus Strains That Differ In The Ability To Cause Disease, Benjamin Brown, Bart Tarbet

Benjamin Hanks Brown

Influenza viruses are classified based on their surface glycoproteins: hemagglutinin and neuraminidase. Hemagglutinin (HA) is responsible for binding to the host cell, while neuraminidase (NA) facilitates escape of newly formed virus particles. These studies determined the NA activity of three subtypes of influenza A virus that differ in their ability to cause disease in mice: influenza A/NWS/33 (H1N1), influenza A/Victoria/3/75 (H3N2), and influenza A/Duck/MN/1525/81 (H5N1). Chemiluminescent quantitation of NA activity in equal amounts of each virus was determined in three replicate experiments. Results indicate that N1 virus subtypes have higher NA ...


Shark Assemblage Structure In The Chesapeake Bight, Kristene T. Parsons, Tracey Sutton, John A. Musick 2010 Virginia Institute of Marine Science

Shark Assemblage Structure In The Chesapeake Bight, Kristene T. Parsons, Tracey Sutton, John A. Musick

Oceanography Faculty Proceedings, Presentations, Speeches, Lectures

The role and importance of the Chesapeake Bight region as essential fish habitat for several species of sharks is well represented in primary literature and US fisheries management plans. Diverse assemblages of shark taxa utilize the Chesapeake Bay and adjacent coasts at various stages throughout their lives. As top predators in most of the environments where they occur, sharks are key to maintaining healthy, diverse ecosystems. The estuarine waters of the Chesapeake Bay are exposed to extreme ranges in temperature and salinity, and consequently the environmental suitability of the Bay is spatially and temporally restricted to select taxa. By identifying ...


The Role Of Rater Motivation In Personnel Selection Validation Studies, Dan Ispas 2010 University of South Florida

The Role Of Rater Motivation In Personnel Selection Validation Studies, Dan Ispas

Graduate Theses and Dissertations

Personnel selection validation studies are routinely conducted in contemporary organizations for selecting and placing employees. Although numerous studies have been conducted with the goal of identifying new predictors, less research was focused on the criterion side. In the current paper, across three studies and five samples, I examined the role played by rater motivation in validation studies. I proposed that rater motivation would impact criterion-related validity of various predictors, the reliability, and the variance of performance ratings. In Study 1, these hypotheses were tested in two samples with varied operationalizations of predictors and of rater motivation. In Study 2, I ...


Low-Frequency Vibrations Of Soft Colloidal Glasses, Ke Chen, Wouter G. Ellenbroek, Zexin Zhang, Daniel T.N. Chen, Peter J. Yunker, Silke Henkes, Carolina Brito, Oliver Dauchot, Wim Van Saarloos, Andrea J. Liu, Arjun G. Yodh 2010 University of Pennsylvania

Low-Frequency Vibrations Of Soft Colloidal Glasses, Ke Chen, Wouter G. Ellenbroek, Zexin Zhang, Daniel T.N. Chen, Peter J. Yunker, Silke Henkes, Carolina Brito, Oliver Dauchot, Wim Van Saarloos, Andrea J. Liu, Arjun G. Yodh

Department of Physics Papers

We conduct experiments on two-dimensional packings of colloidal thermosensitive hydrogel particles whose packing fraction can be tuned above the jamming transition by varying the temperature. By measuring displacement correlations between particles, we extract the vibrational properties of a corresponding ‘‘shadow’’ system with the same configuration and interactions, but for which the dynamics of the particles are undamped. The vibrational properties are very similar to those predicted for zerotemperature sphere packings and found in atomic and molecular glasses; there is a boson peak at low frequency that shifts to higher frequency as the system is compressed above the jamming transition.


Real-Space Approach To Time Dependent Current Density Functional Theory, Daniel S. Jensen 2010 Brigham Young University - Provo

Real-Space Approach To Time Dependent Current Density Functional Theory, Daniel S. Jensen

All Theses and Dissertations

A real-space time-domain calculation of the frequency-dependent dielectric constant of nonmetallic crystals is outlined and the integrals required for this calculation are computed. The outline is based on time dependent current density functional theory and is partially implemented in the ab initio density functional theory FIREBALL program. The addition of a vector potential to the Hamiltonian of the system is discussed as well as the need to include the current density in addition to the particle density. The derivation of gradient integrals within a localized atomic-like orbital basis is presented for use in constructing the current density. Due to the ...


Synthesis Of Glycolipids And Evaluation Of Their Nkt Cell Stimulatory Properties, Yang Liu 2010 Brigham Young University - Provo

Synthesis Of Glycolipids And Evaluation Of Their Nkt Cell Stimulatory Properties, Yang Liu

All Theses and Dissertations

Natural killer T (NKT) cells are a subset of T cells that modify a variety of immune responses. NKT cells recognize glycolipid antigen presented by a molecule called CD1d, a nonclassical antigen-presenting molecule. The best known subset of CD1d-dependent NKT cells expresses an invariant T cell receptor Vα (TCR-α) chain. These are referred to as type I or invariant NKT (iNKT) cells. When stimulated by a glycolipid, NKT cells rapidly release large amounts of cytokines. Cytokines released by NKT cells can induce either Th1 or Th2 responses. Th1 cytokines are effective in regulating bacterial, parasitic, and viral infections. But Th1 ...


Heart And Skeletal Muscle Inflammation Of Farmed Salmon Is Associated With Infection With A Novel Reovirus, Torstein Tengs 2010 Norwegian Veterinary Institute

Heart And Skeletal Muscle Inflammation Of Farmed Salmon Is Associated With Infection With A Novel Reovirus, Torstein Tengs

Dr. Torstein Tengs

Atlantic salmon (Salmo salar L.) mariculture has been associated with epidemics of infectious diseases that threaten not only local production, but also wild fish coming into close proximity to marine pens and fish escaping from them. Heart and skeletal muscle inflammation (HSMI) is a frequently fatal disease of farmed Atlantic salmon. First recognized in one farm in Norway in 1999, HSMI was subsequently implicated in outbreaks in other farms in Norway and the United Kingdom. Although pathology and disease transmission studies indicated an infectious basis, efforts to identify an agent were unsuccessful. Here we provide evidence that HSMI is associated ...


A Hybrid Radial Basis Function-Pseudospectral Method For Thermal Convection In A 3-D Spherical Shell, Grady Wright, Natasha Flyer, David A. Yuen 2010 Boise State University

A Hybrid Radial Basis Function-Pseudospectral Method For Thermal Convection In A 3-D Spherical Shell, Grady Wright, Natasha Flyer, David A. Yuen

Mathematics Faculty Publications and Presentations

A novel hybrid spectral method that combines radial basis function (RBF) and Chebyshev pseudospectral methods in a “2 + 1” approach is presented for numerically simulating thermal convection in a 3‐D spherical shell. This is the first study to apply RBFs to a full 3‐D physical model in spherical geometry. In addition to being spectrally accurate, RBFs are not defined in terms of any surface‐based coordinate system such as spherical coordinates. As a result, when used in the lateral directions, as in this study, they completely circumvent the pole issue with the further advantage that nodes can be ...


Raman Scattering Study Of Phase Biaxiality In A Thermotropic Bent-Core Nematic Liquid Crystal, Min Sang Park, Beom-Kin Yoon, Jung Ok Park, Veena Prasad, Satyendra Kumar, Mohan Srinivasarao 2010 Georgia Institute of Technology - Main Campus

Raman Scattering Study Of Phase Biaxiality In A Thermotropic Bent-Core Nematic Liquid Crystal, Min Sang Park, Beom-Kin Yoon, Jung Ok Park, Veena Prasad, Satyendra Kumar, Mohan Srinivasarao

Physics Publications

Polarized Raman spectroscopy was used to investigate the development of orientational order and the degree of phase biaxiality in a bent-core mesogenic system. The values of the uniaxial order parameters ⟨P200⟩ and ⟨P400⟩, and biaxial order parameters ⟨P220⟩, ⟨P420⟩, and ⟨P440⟩, and their evolution with temperature were determined. The temperature dependence of almost all order parameters reveals a second order transition from the uniaxial to biaxial nematic phase with ⟨P220⟩ increasing to ∼0.22 before a first order transition to the smectic-C phase, upon cooling.


Physical And Chemical Properties Of Ice In A Main Valley Glacier And A Tributary Glacier, Gornergletscher, Canton Valais, Switzerland, Annika M. Quick 2010 Brigham Young University - Provo

Physical And Chemical Properties Of Ice In A Main Valley Glacier And A Tributary Glacier, Gornergletscher, Canton Valais, Switzerland, Annika M. Quick

All Theses and Dissertations

Glacier models often fail to incorporate the geometry and/or physical properties of tributaries included in complex glaciers. Tributary glaciers have different source areas and flow conditions than the adjacent main valley glacier. Ice cores (~3m depth) and surface samples (<0.5m depth) were collected from Grenzgletscher (main valley glacier) and Zwillingsgletscher (tributary glacier) in the Gornergletscher system of the Swiss Alps. Stable water isotopes indicate seasonal variation, showing 1-2 annual layers. The mean d18O for Grenzgletscher is ~4.8‰ lower than for Zwillingsgletscher. This difference may be accounted for in part by elevation differences between the accumulation areas (~1.1‰ δ18O), increased avalanching in Grenzgletscher (~1.8 ‰ δ18O), and by varying climatic conditions at the time of precipitation (~0.9-1.4‰ variation in δ18O). Using a kinematic ice flow model, core ages were estimated using effective annual layer thickness (based on seasonal variations), annual accumulation rate and ice thickness. The Grenzgletscher core is ~4 years older than the Zwillingsgletscher core. Based on ages and flow distances, the tributary has a lower flow velocity (63-87 m/yr) compared to Grenzgletscher (61-134 m/yr). To understand thermal properties of the tributary, a 775 m GPR survey (200 MHz) was conducted along a flow line of Zwillingsgletscher. Topographic waves (ogives) observed on the surface are mimicked by the onset of reflectivity 10-20 m below the surface. Reflective regions are interpreted as warmer ice at the pressure melting point, overlain by colder ice. This thermal structure is likely related to acceleration through an ice fall. Since most tributary glaciers include ice falls, thermal properties of tributary glaciers may be different from those of the main valley glacier. The properties and geometry of tributary glaciers are significantly different from main valley glaciers and should therefore be incorporated into glacier models in the future.


A Probabilistic Morphological Analyzer For Syriac, Peter J. McClanahan 2010 Brigham Young University - Provo

A Probabilistic Morphological Analyzer For Syriac, Peter J. Mcclanahan

All Theses and Dissertations

We show that a carefully crafted probabilistic morphological analyzer significantly outperforms a reasonable, naive baseline for Syriac. Syriac is an under-resourced Semitic language for which there are no available language tools such as morphological analyzers. Such tools are widely used to contribute to the process of annotating morphologically complex languages. We introduce and connect novel data-driven models for segmentation, dictionary linkage, and morphological tagging in a joint pipeline to create a probabilistic morphological analyzer requiring only labeled data. We explore the performance of this model with varying amounts of training data and find that with about 34,500 tokens, it ...


Conformational Dynamics Associated With Calcium Binding To Calcium Transducers, Gangadhar Dhulipala 2010 Florida International University

Conformational Dynamics Associated With Calcium Binding To Calcium Transducers, Gangadhar Dhulipala

FIU Electronic Theses and Dissertations

The Ca2+ association to calcium binding proteins (CaBPs) represents an essential step in Ca2+ signal transduction. This study presents a characterization of Ca interactions with two CaBPs, calmodulin and DREAM, using time-resolved photothermal and fluorescence techniques. Calcium binding to the calmodulin C-terminal domain is associated with a volume change of 40 mL mol-1and an enthalpy change of 35 ± 16 kcal mol-1. These parameters are consistent with the Ca2+ triggered exposure of hydrophobic patches on the calmodulin surface. Also, the rate limiting step for Ca2+ binding to calmodulin is the closed-to-open transition of the ...


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