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Identification Of Arabidopsis Gpat9 (At5g60620) As An Essential Gene Involved In Triacylglycerol Biosynthesis, Jay Shockey, Anushobha Regmi, Kimberly Cotton, Neil Adhikari, John Bowse, Philip D. Bates Dec 2015

Identification Of Arabidopsis Gpat9 (At5g60620) As An Essential Gene Involved In Triacylglycerol Biosynthesis, Jay Shockey, Anushobha Regmi, Kimberly Cotton, Neil Adhikari, John Bowse, Philip D. Bates

Faculty Publications

The first step in the biosynthesis of nearly all plant membrane phospholipids and storage triacylglycerols is catalyzed by a glycerol-3-phosphate acyltransferase (GPAT). The requirement for an endoplasmic reticulum (ER)-localized GPAT for both of these critical metabolic pathways was recognized more than 60 years ago. However, identification of the gene(s) encoding this GPAT activity has remained elusive. Here, we present the results of a series of in vivo, in vitro, and in silico experiments in Arabidopsis (Arabidopsis thaliana) designed to assign this essential function to AtGPAT9. This gene has been highly conserved throughout evolution and is …


Elevation Promotes Long-Term Survival Of Pinus Elliottii Var. Densa, A Foundation Species Of The Endangered Pine Rockland Ecosystem In The Florida Keys, Grant L. Harley, Justin T. Maxwell, George T. Raber Dec 2015

Elevation Promotes Long-Term Survival Of Pinus Elliottii Var. Densa, A Foundation Species Of The Endangered Pine Rockland Ecosystem In The Florida Keys, Grant L. Harley, Justin T. Maxwell, George T. Raber

Faculty Publications

The pine rockland community in southern Florida, which supports numerous state- and federally listed flora and fauna species, is considered endangered. Without its foundation species, Pinus elliottii var. densa, habitat and species diversity are lost to tropical hardwood hammock. Here, we investigate the landscape factors that contribute to the long-term persistence of pine rocklands on the 2 islands that contain the largest remaining habitat in the Florida Keys: Big Pine Key and No Name Key. Plot-level biophysical data and island-scale remotely sensed vegetation data were collected from pine rockland savannas and examined with multi-dimensional analysis. On both islands, vegetation …


No Reef Is An Island: Integrating Coral Reef Connectivity Data Into The Design Of Regional-Scale Marine Protected Area Networks, Steven R. Schill, George T. Raber, Jason J. Roberts, Eric A. Treml, Jorge Brenner, Patrick N. Halpin Dec 2015

No Reef Is An Island: Integrating Coral Reef Connectivity Data Into The Design Of Regional-Scale Marine Protected Area Networks, Steven R. Schill, George T. Raber, Jason J. Roberts, Eric A. Treml, Jorge Brenner, Patrick N. Halpin

Faculty Publications

We integrated coral reef connectivity data for the Caribbean and Gulf of Mexico into a conservation decision-making framework for designing a regional scale marine protected area (MPA) network that provides insight into ecological and political contexts. We used an ocean circulation model and regional coral reef data to simulate eight spawning events from 2008–2011, applying a maximum 30-day pelagic larval duration and 20% mortality rate. Coral larval dispersal patterns were analyzed between coral reefs across jurisdictional marine zones to identify spatial relationships between larval sources and destinations within countries and territories across the region. We applied our results in Marxan, …


Supporting Data For The Characterization Of Pna-Dna Four-Way Junctions, Douglas Van Iverson Ii, Crystal C. Serrano, Ann Marie Brahan, Arik Shams, Filbert Totsingan, Anthony J. Bell Jr. Dec 2015

Supporting Data For The Characterization Of Pna-Dna Four-Way Junctions, Douglas Van Iverson Ii, Crystal C. Serrano, Ann Marie Brahan, Arik Shams, Filbert Totsingan, Anthony J. Bell Jr.

Faculty Publications

Holliday or DNA four-way junctions (4WJs) are cruciform/bent structures composed of four DNA duplexes. 4WJs are key intermediates in homologous genetic recombination and double-strand break repair. To investigate 4WJs in vitro, junctions are assembled using four asymmetric DNA strands. The presence of four asymmetric strands about the junction branch point eliminates branch migration, and effectively immobilizes the resulting 4WJ. The purpose of these experiments is to show that immobile 4WJs composed of DNA and peptide nucleic acids (PNAs) can be distinguished from contaminating labile nucleic acid structures. These data compare the electrophoretic mobility of hybrid PNA–DNA junctions vs. …


An Enantiodivergent Synthesis Of CΑ-Methyl Nipecotic Acid Analogues From δ-Lactam Derivatives Obtained Through A Highly Stereoselective Cyclization Strategy, Souvik Banerjee, Emily R. Vogel, Daniel Hinton, Michael Sterling, Douglas S. Masterson Dec 2015

An Enantiodivergent Synthesis Of CΑ-Methyl Nipecotic Acid Analogues From δ-Lactam Derivatives Obtained Through A Highly Stereoselective Cyclization Strategy, Souvik Banerjee, Emily R. Vogel, Daniel Hinton, Michael Sterling, Douglas S. Masterson

Faculty Publications

A stereoselective and enantiodivergent strategy for the construction of δ-lactams is described. The strategy utilizes chiral malonic esters prepared from enantiomerically enriched mono esters of disubstituted malonic acid. A cyclization occurs with the selective displacement of a substituted benzyl alcohol as the leaving group. The resulting δ-lactams are then converted into nipecotic acid analogues using straightforward transformations. The resulting nipecotic acid analogues proved capable organocatalysts in Mannich reactions.


Structural Characterization Of A Newly Identified Component Of Α-Carboxysomes: The Aaa+ Domain Protein Csocbbq, Markus Sutter, Evan W. Roberts, Raul C. Gonzalez, Cassandra Bates, Salma Dawoud, Kimberly Landry, Gordon C. Cannon, Sabine Heinhorst, Cheryl A. Kerfeld Nov 2015

Structural Characterization Of A Newly Identified Component Of Α-Carboxysomes: The Aaa+ Domain Protein Csocbbq, Markus Sutter, Evan W. Roberts, Raul C. Gonzalez, Cassandra Bates, Salma Dawoud, Kimberly Landry, Gordon C. Cannon, Sabine Heinhorst, Cheryl A. Kerfeld

Faculty Publications

Carboxysomes are bacterial microcompartments that enhance carbon fixation by concentrating ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and its substrate CO2 within a proteinaceous shell. They are found in all cyanobacteria, some purple photoautotrophs and many chemoautotrophic bacteria. Carboxysomes consist of a protein shell that encapsulates several hundred molecules of RuBisCO and contain carbonic anhydrase and other accessory proteins. Genes coding for carboxysome shell components and the encapsulated proteins are typically found together in an operon. The α-carboxysome operon is embedded in a cluster of additional, conserved genes that are presumably related to its function. In many chemoautotrophs, products of the expanded carboxysome …


Abundance, Stable Isotopic Composition, And Export Fluxes Of Doc, Poc, And Dic From The Lower Mississippi River During 2006-2008, Yihua Cai, Laodong Guo, Xuri Wang, George Aiken Nov 2015

Abundance, Stable Isotopic Composition, And Export Fluxes Of Doc, Poc, And Dic From The Lower Mississippi River During 2006-2008, Yihua Cai, Laodong Guo, Xuri Wang, George Aiken

Faculty Publications

Sources, abundance, isotopic compositions, and export fluxes of dissolved inorganic carbon (DIC), dissolved and colloidal organic carbon (DOC and COC), and particulate organic carbon (POC), and their response to hydrologic regimes were examined through monthly sampling from the Lower Mississippi River during 2006–2008. DIC was the most abundant carbon species, followed by POC and DOC. Concentration and δ13C of DIC decreased with increasing river discharge, while those of DOC remained fairly stable. COC comprised 61 ± 3% of the bulk DOC with similar δ13C abundances but higher percentages of hydrophobic organic acids than DOC, suggesting its …


Preparation And Preliminary Dielectric Characterization Of Structured C60-Thiol-Ene Polymer Nanocomposites Assembled Using The Thiol-Ene Click Reaction, Hanaa Mohammed Ahmed, Amber Danielle Windham, Maryam M. Al-Ejji, Noora H. Al-Qahtani, Mohammad K. Hassan, Kenneth A. Mauritz, Randy K. Buchanan, J. Paige Buchanan Nov 2015

Preparation And Preliminary Dielectric Characterization Of Structured C60-Thiol-Ene Polymer Nanocomposites Assembled Using The Thiol-Ene Click Reaction, Hanaa Mohammed Ahmed, Amber Danielle Windham, Maryam M. Al-Ejji, Noora H. Al-Qahtani, Mohammad K. Hassan, Kenneth A. Mauritz, Randy K. Buchanan, J. Paige Buchanan

Faculty Publications

Fullerene-containing materials have the ability to store and release electrical energy. Therefore, fullerenes may ultimately find use in high-voltage equipment devices or as super capacitors for high electric energy storage due to this ease of manipulating their excellent dielectric properties and their high volume resistivity. A series of structured fullerene (C60) polymer nanocomposites were assembled using the thiol-ene click reaction, between alkyl thiols and allyl functionalized C60 derivatives. The resulting high-density C60-urethane-thiol-ene (C60-Thiol-Ene) networks possessed excellent mechanical properties. These novel networks were characterized using standard techniques, including infrared spectroscopy (FTIR), differential scanning calorimetry …


Force-Enhanced Atomic Refinement: Structural Modeling With Interatomic Forces In A Reverse Monte Carlo Approach Applied To Amorphous Si And Sio2, A. Pandey, Parthapratim Biswas, D. A. Drabold Oct 2015

Force-Enhanced Atomic Refinement: Structural Modeling With Interatomic Forces In A Reverse Monte Carlo Approach Applied To Amorphous Si And Sio2, A. Pandey, Parthapratim Biswas, D. A. Drabold

Faculty Publications

We introduce a structural modeling technique, called force-enhanced atomic refinement (FEAR). The technique incorporates interatomic forces in reverse Monte Carlo (RMC) simulations for structural refinement by fitting experimental diffraction data using the conventional RMC algorithm, and minimizes the total energy and forces from an interatomic potential. We illustrate the usefulness of the approach by studying a−SiO2 and a−Si. The structural and electronic properties of the FEAR models agree well with experimental neutron and x-ray diffraction data and the results obtained from previous molecular dynamics simulations of a−SiO2 and a−Si. We have shown that the method is more efficient …


Sculpting The Band Gap: A Computational Approach, Kiran Prasai, Parthapratim Biswas, D.A. Drabold Oct 2015

Sculpting The Band Gap: A Computational Approach, Kiran Prasai, Parthapratim Biswas, D.A. Drabold

Faculty Publications

Materials with optimized band gap are needed in many specialized applications. In this work, we demonstrate that Hellmann-Feynman forces associated with the gap states can be used to find atomic coordinates that yield desired electronic density of states. Using tight-binding models, we show that this approach may be used to arrive at electronically designed models of amorphous silicon and carbon. We provide a simple recipe to include a priori electronic information in the formation of computer models of materials, and prove that this information may have profound structural consequences. The models are validated with plane-wave density functional calculations.


A Generalized Force-Modified Potential Energy Surface For Mechanochemical Simulations, Gopinath Subramanian, Nithin Mathew, Jeff Leiding Oct 2015

A Generalized Force-Modified Potential Energy Surface For Mechanochemical Simulations, Gopinath Subramanian, Nithin Mathew, Jeff Leiding

Faculty Publications

We describe the modifications that a spatially varying external load produces on a Born-Oppenheimer potential energy surface (PES) by calculating static quantities of interest. The effects of the external loads are exemplified using electronic structure calculations (at the HF/6-31G- level) of two different molecules: ethane and hexahydro-1,3,5-trinitro-s-triazine (RDX). The calculated transition states and Hessian matrices of stationary points show that spatially varying external loads shift the stationary points and modify the curvature of the PES, thereby affecting the harmonic transition rates by altering both the energy barrier as well as the prefactor. The harmonic spectra of both molecules are blueshifted …


Relativistic Elastic Differential Cross Sections For Equal Mass Nuclei, Charles M. Werneth, Khin M. Maung, W.P. Ford Oct 2015

Relativistic Elastic Differential Cross Sections For Equal Mass Nuclei, Charles M. Werneth, Khin M. Maung, W.P. Ford

Faculty Publications

The effects of relativistic kinematics are studied for nuclear collisions of equal mass nuclei. It is found that the relativistic and non-relativistic elastic scattering amplitudes are nearly indistinguishable, and, hence, the relativistic and non-relativistic differential cross sections become indistinguishable. These results are explained by analyzing the Lippmann–Schwinger equation with the first order optical potential that was employed in the calculation.


Differential Effects Of Munc18s On Multiple Degranulation-Relevant Trans-Snare Complexes, Hao Xu, Matthew Grant Arnold, Sushmitha Vijay Kumar Sep 2015

Differential Effects Of Munc18s On Multiple Degranulation-Relevant Trans-Snare Complexes, Hao Xu, Matthew Grant Arnold, Sushmitha Vijay Kumar

Faculty Publications

Mast cell exocytosis, which includes compound degranulation and vesicle-associated piecemeal degranulation, requires multiple Q- and R- SNAREs. It is not clear how these SNAREs pair to form functional trans-SNARE complexes and how these trans-SNARE complexes are selectively regulated for fusion. Here we undertake a comprehensive examination of the capacity of two Q-SNARE subcomplexes (syntaxin3/SNAP-23 and syntaxin4/SNAP-23) to form fusogenic trans-SNARE complexes with each of the four granule-borne R-SNAREs (VAMP2, 3, 7, 8). We report the identification of at least six distinct trans-SNARE complexes under enhanced tethering conditions: i) VAMP2/syntaxin3/SNAP-23, ii) VAMP2/syntaxin4/SNAP-23, iii) VAMP3/syntaxin3/SNAP-23, iv) VAMP3/syntaxin4/SNAP-23, v) VAMP8/syntaxin3/SNAP-23, and vi) VAMP8/syntaxin4/SNAP-23. …


Indirect Evidence For Substantial Damping Of Low-Mode Internal Tides In The Open Ocean, Joseph K. Ansong, Brian K. Arbic, Maarten C. Buijsman, James G. Richman, Jay F. Shriver, Alan J. Wallcraft Sep 2015

Indirect Evidence For Substantial Damping Of Low-Mode Internal Tides In The Open Ocean, Joseph K. Ansong, Brian K. Arbic, Maarten C. Buijsman, James G. Richman, Jay F. Shriver, Alan J. Wallcraft

Faculty Publications

A global high-resolution ocean circulation model forced by atmospheric fields and the M2 tidal constituent is used to explore plausible scenarios for the damping of low-mode internal tides. The plausibility of different damping scenarios is tested by comparing the modeled barotropic tides with TPXO8, a highly accurate satellite-altimetry-constrained tide model, and by comparing the modeled coherent baroclinic tide amplitudes against along-track altimetry. Five scenarios are tested: (1) a topographic internal wave drag, argued here to represent the breaking of unresolved high vertical modes, applied to the bottom flow (default configuration), (2) a wave drag applied to the barotropic flow, …


Chesapeake Bay Nitrogen Fluxes Derived From A Land-Estuarine Ocean Biogeochemical Modeling System: Model Description, Evaluation, And Nitrogen Budgets, Yang Feng, Marjorie A.M. Friedrichs, John Wilkin, Hanqin Tian, Qichun Yang, Eileen E. Hofmann, Jerry D. Wiggert, Raleigh R. Hood Aug 2015

Chesapeake Bay Nitrogen Fluxes Derived From A Land-Estuarine Ocean Biogeochemical Modeling System: Model Description, Evaluation, And Nitrogen Budgets, Yang Feng, Marjorie A.M. Friedrichs, John Wilkin, Hanqin Tian, Qichun Yang, Eileen E. Hofmann, Jerry D. Wiggert, Raleigh R. Hood

Faculty Publications

The Chesapeake Bay plays an important role in transforming riverine nutrients before they are exported to the adjacent continental shelf. Although the mean nitrogen budget of the Chesapeake Bay has been previously estimated from observations, uncertainties associated with interannually varying hydrological conditions remain. In this study, a land-estuarine-ocean biogeochemical modeling system is developed to quantify Chesapeake riverine nitrogen inputs, within-estuary nitrogen transformation processes and the ultimate export of nitrogen to the coastal ocean. Model skill was evaluated using extensive in situ and satellite-derived data, and a simulation using environmental conditions for 2001–2005 was conducted to quantify the Chesapeake Bay nitrogen …


The Evolution Of Mode-2 Nonlinear Internal Waves Over The Northern Heng-Chun Ridge South Of Taiwan, S.R. Ramp, Y.J. Yang, D.B. Reeder, Maarten C. Buijsman, F.L. Bahr Jul 2015

The Evolution Of Mode-2 Nonlinear Internal Waves Over The Northern Heng-Chun Ridge South Of Taiwan, S.R. Ramp, Y.J. Yang, D.B. Reeder, Maarten C. Buijsman, F.L. Bahr

Faculty Publications

Two research cruises were conducted from the R/V OCEAN RESEARCHER 3 during 05–16 August 2011 to study the generation and propagation of high-frequency nonlinear internal waves (NLIWs) over the northern Heng-Chun Ridge south of Taiwan. The primary study site was on top of a smaller ridge about 15 km wide by 400 m high atop the primary ridge, with a sill depth of approximately 600 m. A single mooring was used in conjunction with shipboard observations to sample the temperature, salinity and velocity structure over the ridge. All the sensors observed a profusion of mode-2 NLIWs. Some of the waves …


Structural Variation Of Alpha-Synuclein With Temperature By A Coarse-Grained Approach With Knowledge-Based Interactions, Peter Mirau, Barry L. Farmer, Ras B. Pandey Jul 2015

Structural Variation Of Alpha-Synuclein With Temperature By A Coarse-Grained Approach With Knowledge-Based Interactions, Peter Mirau, Barry L. Farmer, Ras B. Pandey

Faculty Publications

Despite enormous efforts, our understanding the structure and dynamics of α-synuclein (ASN), a disordered protein (that plays a key role in neurodegenerative disease) is far from complete. In order to better understand sequence-structure-property relationships in α-SYNUCLEIN we have developed a coarse-grained model using knowledge-based residue-residue interactions and used it to study the structure of free ASN as a function of temperature (T) with a large-scale Monte Carlo simulation. Snapshots of the simulation and contour contact maps show changes in structure formation due to self-assembly as a function of temperature. Variations in the residue mobility profiles reveal clear distinction among three …


Advances In Understanding Carboxysome Assembly In Prochlorococcus And Synechococcus Implicate Csos2 As A Critical Component, Fei Cai, Zhicheng Dou, Susan L. Bernstein, Ryan Leverenz, Eric B. Williams, Sabine Heinhorst, Jessup M. Shively, Gordon C. Cannon, Cheryl A. Kerfeld Jun 2015

Advances In Understanding Carboxysome Assembly In Prochlorococcus And Synechococcus Implicate Csos2 As A Critical Component, Fei Cai, Zhicheng Dou, Susan L. Bernstein, Ryan Leverenz, Eric B. Williams, Sabine Heinhorst, Jessup M. Shively, Gordon C. Cannon, Cheryl A. Kerfeld

Faculty Publications

The marine Synechococcus and Prochlorococcus are the numerically dominant cyanobacteria in the ocean and important in global carbon fixation. They have evolved a CO2-concentrating-mechanism, of which the central component is the carboxysome, a self-assembling proteinaceous organelle. Two types of carboxysome, α and β, encapsulating form IA and form IB d-ribulose-1,5-bisphosphate carboxylase/oxygenase, respectively, differ in gene organization and associated proteins. In contrast to the β-carboxysome, the assembly process of the α-carboxysome is enigmatic. Moreover, an absolutely conserved α-carboxysome protein, CsoS2, is of unknown function and has proven recalcitrant to crystallization. Here, we present studies on the CsoS2 protein in …


Efficient Esterification Of Oxidized L-Glutathione And Other Small Peptides, Emily Rose Vogel, William Jackson, Douglas S. Masterson Dr. Jun 2015

Efficient Esterification Of Oxidized L-Glutathione And Other Small Peptides, Emily Rose Vogel, William Jackson, Douglas S. Masterson Dr.

Faculty Publications

xidized l-glutathione was esterified to the tetra methyl ester using thionyl chloride in methanol solvent. Other alcohols were tested and the reaction progress was monitored via ESI-MS. This procedure proved to be compatible with other small peptides not containing serine and cysteine residues. In contrast to previously reported methods this procedure provided convenient access to esterified peptides requiring no purification, extended reaction times, or complicated reaction setups.


Self-Assembly Dynamics For The Transition Of A Globular Aggregate To A Fibril Network Of Lysozyme Proteins Via A Coarse-Grained Monte Carlo Simulation, Ras B. Pandey, Barry L. Farmer, Bernard S. Gerstman May 2015

Self-Assembly Dynamics For The Transition Of A Globular Aggregate To A Fibril Network Of Lysozyme Proteins Via A Coarse-Grained Monte Carlo Simulation, Ras B. Pandey, Barry L. Farmer, Bernard S. Gerstman

Faculty Publications

The self-organizing dynamics of lysozymes (an amyloid protein with 148 residues) with different numbers of protein chains, Nc = 1,5,10, and 15(concentration 0.004 – 0.063) is studied by a coarse-grained Monte Carlo simulation with knowledge-based residue-residue interactions. The dynamics of an isolated lysozyme (Nc = 1) is ultra-slow (quasi-static) at low temperatures and becomes diffusive asymptotically on raising the temperature. In contrast, the presence of interacting proteins leads to concentration induced protein diffusion at low temperatures and concentration-tempering sub-diffusion at high temperatures. Variation of the radius of gyration of the protein with temperature shows a …


Going With The Flow Or Against The Grain? The Promise Of Vegetation For Protecting Beaches, Dunes, And Barrier Islands From Erosion, Rusty A. Feagin, Jens Figlus, Julie C. Zinnert, Jake Sigren, Marisa L. Martínez, Rodolfo Silva, William K. Smith, Ashley Cox, Daniel Cox, Donald R. Young, Gregory A. Carter May 2015

Going With The Flow Or Against The Grain? The Promise Of Vegetation For Protecting Beaches, Dunes, And Barrier Islands From Erosion, Rusty A. Feagin, Jens Figlus, Julie C. Zinnert, Jake Sigren, Marisa L. Martínez, Rodolfo Silva, William K. Smith, Ashley Cox, Daniel Cox, Donald R. Young, Gregory A. Carter

Faculty Publications

Coastlines have traditionally been engineered to maintain structural stability and to protect property from storm‐related damage, but their ability to endure will be challenged over the next century. The use of vegetation to reduce erosion on ocean‐facing mainland and barrier island shorelines – including the sand dunes and beaches on these islands – could be part of a more flexible strategy. Although there is growing enthusiasm for using vegetation for this purpose, empirical data supporting this approach are lacking. Here, we identify the potential roles of vegetation in coastal protection, including the capture of sediment, ecological succession, and the building …


A Kansa-Radial Basis Function Method For Elliptic Boundary Value Problems In Annular Domains, Xiao Yan Liu, Andreas Karageorghis, C. S. Chen Mar 2015

A Kansa-Radial Basis Function Method For Elliptic Boundary Value Problems In Annular Domains, Xiao Yan Liu, Andreas Karageorghis, C. S. Chen

Faculty Publications

We employ a Kansa-radial basis function (RBF) method for the numerical solution of elliptic boundary value problems in annular domains. This discretization leads, with an appropriate selection of collocation points and for any choice of RBF, to linear systems in which the matrices possess block circulant structures. These linear systems can be solved efficiently using matrix decomposition algorithms and fast Fourier transforms. A suitable value for the shape parameter in the various RBFs used is found using the leave-one-out cross validation algorithm. In particular, we consider problems governed by the Poisson equation, the inhomogeneous biharmonic equation and the inhomogeneous Cauchy–Navier …


Impact Of Homogeneous Strain On Uranium Vacancy Diffusion In Uranium Dioxide, Anuj Goyal, Simon R. Phillpot, Gopinath Subramanian, David A. Andersson, Chris R. Stanek, Blas P. Uberuaga Mar 2015

Impact Of Homogeneous Strain On Uranium Vacancy Diffusion In Uranium Dioxide, Anuj Goyal, Simon R. Phillpot, Gopinath Subramanian, David A. Andersson, Chris R. Stanek, Blas P. Uberuaga

Faculty Publications

We present a detailed mechanism of, and the effect of homogeneous strains on, the migration of uranium vacancies in UO2. Vacancy migration pathways and barriers are identified using density functional theory and the effect of uniform strain fields are accounted for using the dipole tensor approach. We report complex migration pathways and noncubic symmetry associated with the uranium vacancy in UO2 and show that these complexities need to be carefully accounted for to predict the correct diffusion behavior of uranium vacancies. We show that under homogeneous strain fields, only the dipole tensor of the saddle with respect …


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

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

Faculty Publications

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


A Simple Method For Tuning The Glass Transition Process In Inorganic Phosphate Glasses, René Fulchiron, Imane Belyamani, Joshua U. Otaigbe, Véronique Bounor-Legaré Feb 2015

A Simple Method For Tuning The Glass Transition Process In Inorganic Phosphate Glasses, René Fulchiron, Imane Belyamani, Joshua U. Otaigbe, Véronique Bounor-Legaré

Faculty Publications

The physical modification of glass transition temperature (Tg) and properties of materials via blending is a common practice in industry and academia and has a large economic advantage. In this context, simple production of hitherto unattainable new inorganic glass blends from already existing glass compositions via blending raises much hope with the potential to provide new glasses with new and improved properties, that cannot be achieved with classical glass synthesis, for a plethora of applications such as computers screens, glass-to-metal seals, and storage materials for nuclear wastes. Here, we demonstrate that blends of the specific glass compositions …


Lifetime Measurement Of The Cesium 6p3/2 Level Using Ultrafast Pump-Probe Laser Pulses, B. M. Patterson, J. F. Sell, T. Ehrenreich, M. A. Gearba, G. M. Brooke, J. Scoville, R. J. Knize Jan 2015

Lifetime Measurement Of The Cesium 6p3/2 Level Using Ultrafast Pump-Probe Laser Pulses, B. M. Patterson, J. F. Sell, T. Ehrenreich, M. A. Gearba, G. M. Brooke, J. Scoville, R. J. Knize

Faculty Publications

Using the inherent timing stability of pulses from a mode-locked laser, we measure the cesium 6P3/2 excited-state lifetime. An initial pump pulse excites cesium atoms in two counterpropagating atomic beams to the 6P3/2 level. A subsequent synchronized probe pulse ionizes atoms that remain in the excited state and the photoions are collected and counted. By selecting pump pulses that vary in time with respect to the probe pulses, we obtain a sampling of the excited-state population in time, resulting in a lifetime value of 30.462(46) ns. The measurement uncertainty (0.15%) is slightly larger than our previous report of …


Learning Love From A Tiger: Approaches To Nature In An American Buddhist Monastery, Daniel S. Capper Jan 2015

Learning Love From A Tiger: Approaches To Nature In An American Buddhist Monastery, Daniel S. Capper

Faculty Publications

In current debates about Buddhist approaches to the non-human natural world, studies describe Buddhism variously as anthropocentric, biocentric or ecocentric. These perspectives derive for the most part from examinations of philosophical and normative aspects of the tradition without much attention to moments when embodied practice diverges from religious ideals. Responding to the need for narrative thick descriptions of lived Buddhist attitudes toward nature, I ethnographically explore a Vietnamese monastery in the United States. There I find multifaceted Buddhist approaches to nature which sometimes disclose disunity between theory and practice. Philosophically and normatively, this monastery embraces ecocentrism through notions of interconnectedness, …