Physical Sciences and Mathematics Commons^™

Pyridoxamine Traps Intermediates In Lipid Peroxidation Reactions In Vivo: Evidence On The Role Of Lipids In Chemical Modification Of Protein And Development Of Diabetic Complications, Thomas O. Metz, Nathan L. Alderson, Mark E. Chachich, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

Maillard or browning reactions between reducing sugars and protein lead to formation of advanced glycation end products (AGEs) and are thought to contribute to the pathogenesis of diabetic complications. AGE inhibitors such as aminoguanidine and pyridoxamine (PM) inhibit both the formation of AGEs and development of complications in animal models of diabetes. PM also inhibits the chemical modification of protein by advanced lipoxidation end products (ALEs) during lipid peroxidation reactions in vitro. We show here that several PM adducts, formed in incubations of PM with linoleate and arachidonate in vitro, are also excreted in the urine of PM-treated animals. The …

Solar Neutrinos, Sno And Neutrino-Deuteron Reactions, Vladimir Gudkov, Kuniharu Kubodera

Faculty Publications

The standard nuclear physics approach and effective field theory approach for calculations of neutrino–deuteron cross sections for the solar neutrino energies are considered. Their main features, the level of accuracy and problems to be addressed for further developments are discussed.

Search For ΝΜ→ΝE Oscillations In The Nomad Experiment, Nomad Collaboration, P. Astier, D. Autiero, A. Baldisseri, M. Baldo-Ceolin, M. Banner, G. Bassompierre, K. Benslama, N. Besson, I. Bird, B. Blumenfeld, F. Bobisut, J. Bouchez, S. Boyd, A. Bueno, S. Buyatov, L. Camilleri, A. Cardini, P. W. Cattaneo, V. Cavasinni, Roberto Petti, Et. Al.

Faculty Publications

We present the results of a search for ν_µ → ν_e oscillations in the NOMAD experiment at CERN. The experiment looked for the appearance of ν_e in a predominantly ν_µ wide-band neutrino beam at the CERN SPS. No evidence for oscillations was found. The 90% confidence limits obtained are ∆m² < 0.4 eV² for maximal mixing and sin²(2θ)−3 for large ∆m². This result excludes the LSND allowed region of oscillation parameters with ∆m² ≳∆10 eV².

High-Field Measurements Of Electron Decoherence Time In Metallic Nanowires: Switching Off Magnetic Impurity Spins, P. Mohanty, Richard A. Webb

Faculty Publications

We report low-temperature measurements of electron decoherence time in a series of pure gold wires, 18 nm thick and 30 nm wide. At fields up to 15 T, large enough to polarize any concentration of magnetic impurity spins, conductance fluctuation measurements show almost no temperature dependence of the decoherence time below 300 mK, both in the correlation field for interference and the root-mean-square value of the fluctuations. Combined with previous low-field weak localization measurements on samples from similar material, our experiment suggests that the ubiquitous saturation of decoherence time in these samples is not due to any mechanism based on …

Focusing Of Spin Polarization In Semiconductors By Inhomogeneous Doping, Yuriy V. Pershin Dr, Vladimir Privman

Faculty Publications

We study the evolution and distribution of nonequilibrium electron spin polarization in n-type semiconductors within the two-component drift-diffusion model in an applied electric field. Propagation of spin-polarized electrons through a boundary between two semiconductor regions with different doping levels is considered.We assume that inhomogeneous spin polarization is created locally and driven through the boundary by the electric field.We show that an initially created narrow region of spin polarization can be further compressed and amplified near the boundary. Since the boundary involves variation of doping but no real interface between two semiconductor materials, no significant spin polarization loss is expected. …

Links Between Snow Cover, Surface Skin Temperature, And Rainfall Variability In The North American Monsoon System, Toshi Matsui, Venkataraman Lakshmi, Eric Small

Faculty Publications

The influence of land–atmosphere interactions on the variability of the North American monsoon system(NAMS) is investigated using the Television Infrared Observation Satellite (TIROS) Operational Vertical Sounder(TOVS) Pathfinder, the Climate Prediction Center (CPC) gauge precipitation, and observed snow water equivalent(SWE). Three hypotheses are tested regarding the connection between land surface variables and precipitationin the NAMS region. First, there is a weak negative correlation between 1 April SWE and subsequent surfacetemperature in the southern Rocky Mountains (SRM) region. However, this connection persists only until Juneand, therefore, cannot directly influence monsoon rainfall in July and August. Second, there is a negativecorrelation between SRM …

Bis[Μ-1,2-Bis(2-Pyridyl)Ethyne-K2N:N']Bis[Aquadinitratocadmium(Ii)], Badruz Zaman Md., Matthew J. Davis, Mark D. Smith, Hans Conrad Zur Loye

Faculty Publications

Two twisted 1,2-bis(2-pyridyl)ethyne ligands bridge two Cd²⁺ centers in the C₂-symmetric title complex, [Cd₂(NO₃)₄(-C₁₂H₈N₂)₂(H₂O)₂]. The bridging ligands arch across one another creating a `zigzag loop' molecular geometry. Two nitrate ions and a water molecule complete the irregular seven-coordinate Cd-atom environment. The dihedral angles between the equivalent pyridyl ring planes of the two independent ligands are 67.2 (1)°. O_water-HO_nitrate hydrogen bonding creates two-dimensional layers parallel to the ab plane.

Formula: [Cd₂(NO₃)₄(C …

Eocene To Miocene Magnetostratigraphy, Biostratigraphy, And Chemostratigraphy At Odp Site 1090 (Sub-Antarctic South Atlantic), J E T Channell, S Galeotti, Ellen E. Martin, K Billups, Howie Scher, J S. Stoner

Faculty Publications

At Ocean Drilling Program (ODP) Site 1090 (lat 42854.89S, long 8854.09E) locatedin a water depth of 3702 m on the Agulhas Ridge in the sub-Antarctic South Atlantic, ~300 m of middle Eocene to middle Miocenesediments were recovered with the advancedpiston corer (APC) and the extendedcore barrel (XCB). U-channel samplesfrom the 70–230 meters composite depth(mcd) interval provide a magnetic polaritystratigraphy that is extended to 380 mcd byshipboard whole-core and discrete sampledata. The magnetostratigraphy can be interpretedby the fit of the polarity-zone patternto the geomagnetic polarity time scale(GPTS) augmented by isotope data andbioevents with documented correlation tothe GPTS. Three normal-polarity subchrons(C5Dr.1n, C7Ar.1n, …

Sr3Mgpto6, Mark D. Smith, Hans Conrad Zur Loye

Faculty Publications

Single crystals of the mixed alkaline earth platinate, tristrontium magnesium platinum hexaoxide, Sr₃MgPtO₆, were grown from a KOH flux at 1273 K. The compound adopts the rhombohedral K₄CdCl₆ structure type, featuring chains of face-shared, distorted MgO₆ trigonal prisms (Mg site symmetry 32) and PtO₆ octahedra (Pt site symmetry ) surrounded by columns of Sr²⁺ ions (Sr site symmetry 2).

Influence Of A Cyclonic Eddy On Microheterotroph Biomass And Carbon Export In The Lee Of Hawaii, Robert R. Bidigare, Claudia R. Benitez-Nelson, Carrie L. Leonard, Paul D. Quay, Michael L. Parsons, David G. Foley, Michael P. Seki

Faculty Publications

[1] A multi‐platform sampling strategy was used to investigate carbon cycling in a cold‐core eddy that formed in the lee of Hawaii during September 2000. Microheterotroph biomass and 234Th‐derived carbon export rates within the eddy were 2 to 3 times higher than those observed for adjacent waters. If this eddy is representative of other cyclonic eddies that are frequently formed in the lee of Hawaii, then eddy activity may significantly enhance the areal efficiency of the biological pump and facilitate the transfer of organic carbon to organisms inhabiting the mesopelagic and abyssal‐benthic zones of this subtropical ecosystem.

Probing Tectonic Topography In The Aftermath Of Continental Convergence In Central Europe, S Cloetingh, F Horvath, C Dinu, R A. Stephenson, G Bertotti, G Bada, L Matenco, D Garcia-Castellanos, P Andriessen, R Wortel, W Spakman, V Mocanu, C Langereis, W Krijgsman, J Fokkema, G Drykoningen, B Ambrosius, F Neubauer, L Fodor, T Dunai, E Willingshofer, A Nador, K Leever, M Tarapoanca, I Panea, I Vasiliev, G Paicu, A Van Der Hoven, James H. Knapp, Camelia C. Diaconescu, St Freimueller

Faculty Publications

Continental topography is at the interface of processes taking place at depth in the Earth,at its surface,and above it.Topography influences society, not only in terms of slow processes of landscape change and earthquakes,but also in terms of how it affects climate.The Pannonian Basin–Carpathian Orogen System in Central and Eastern Europe represents a key natural laboratory for the development of a new generation of models for ongoing orogeny and its effect on continental topography development (Figure 1).This system comprises some of the best documented sedimentary basins in the world,located within the Alpine orogenic belt, at the transition between the western European …

Semiclassical Dynamics With Quantum Trajectories: Formulation And Comparison With The Semiclassical Initial Value Representation Propagator, Sophya Garashchuk, Vitaly A. Rassolov

Faculty Publications

We present a time-dependent semiclassical method based on quantum trajectories. Quantum-mechanical effects are described via the quantum potential computed from the wave function density approximated as a linear combination of Gaussian fitting functions. The number of the fitting functions determines the accuracy of the approximate quantum potential (AQP). One Gaussian fit reproduces time-evolution of a Gaussian wave packet in a parabolic potential. The limit of the large number of fitting Gaussians and trajectories gives the full quantum-mechanical result. The method is systematically improvable from classical to fully quantum. The fitting procedure is implemented as a gradient minimization. We also compare …

Magmatic Subsidence Of The East Pacific Rise (Epr) At 18˚14'S Revealed Through Fault Restoration Of Ridge Crest Bathymetry, S M. Carbotte, William B F Ryan, Wen Jin, Marie-Helene Cormier, Eric Bergmanis, John Sinton, Scott M. White

Faculty Publications

The fault restoration technique of De Chabalier and Avouac [1994] is applied to an ultra-highresolution bathymetry data set from the East Pacific Rise (EPR) at 18140S. Fault offsets are calculated and subtracted from the original seafloor bathymetry to examine the morphology of the unfaulted seafloor surface within an area encompassing the ridge axis 400 [1] 1600 m in dimension. The restored topography reveals a gently sloping seafloor 200 m wide, which slopes 5 inward toward the spreading axis. We attribute this inward sloping seafloor to subsidence within the axial trough due to subsurface magmatic deflation. The vertical deformation field extracted …

Nitroalkane Anomaly: Computational Study With Cluster And Continuum Modeling, H. Yamataka, Salai Cheettu Ammal

Faculty Publications

The origin of anomalous relation between rates and equilibria for the proton-transfer reactions of nitroalkanes, known as nitroalkane anomaly, was investigated by theoretical calculations with a cluster model, in which three water molecules are explicitly considered in the system, as well as the PCM solvent continuum model. For the CH3NO2/CH3CH2NO2 system, B3LYP and MP2 computations reproduced the anomaly, and the imbalance in the charge distribution at the transition state (TS) was observed. In contrast, although the TS imbalance was detected for the substituted phenylnitromethane system, the Brønsted plots did not show any anomaly. The experimentally observed abnormally large Brønsted coefficient …

Semiclassical Dynamics With Quantum Trajectories: Formulation And Comparison With The Semiclassical Initial Value Representation Propagator, Sophya V. Garashchuk, V. A. Rassolov

Faculty Publications

We present a time-dependent semiclassical method based on quantum trajectories. Quantum-mechanical effects are described via the quantum potential computed from the wave function density approximated as a linear combination of Gaussian fitting functions. The number of the fitting functions determines the accuracy of the approximate quantum potential (AQP). One Gaussian fit reproduces time-evolution of a Gaussian wave packet in a parabolic potential. The limit of the large number of fitting Gaussians and trajectories gives the full quantum-mechanical result. The method is systematically improvable from classical to fully quantum. The fitting procedure is implemented as a gradient minimization. We also compare …

Methods And Models For Estimating Advective Pore Water Exchange In Tidal Flats, Timothy J. Shaw

Faculty Publications

No abstract provided.