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2007

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Articles 18421 - 18450 of 22017

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Influence Of Modifier Oxides On The Structural And Optical Properties Of Binary Teo2 Glasses, C. Rivero, R. Stegeman, K. Richardson, G. Stegeman, G. Turri, M. Bass, P. Thomas, M. Udovic, T. Cardinal, E. Fargin, M. Couzi, H. Jain, A. Miller Jan 2007

Influence Of Modifier Oxides On The Structural And Optical Properties Of Binary Teo2 Glasses, C. Rivero, R. Stegeman, K. Richardson, G. Stegeman, G. Turri, M. Bass, P. Thomas, M. Udovic, T. Cardinal, E. Fargin, M. Couzi, H. Jain, A. Miller

Faculty Bibliography 2000s

Five different glass compositions with equal TeO2 molar concentration and various intermediate constituents were prepared to examine the influence of such intermediate species on the tellurite network. A correlation between the glasses' structural network and optical properties is presented. Peak Raman gain coefficients, on the order of 40 times the gain of SiO2, are reported in this paper.

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Wireless Pressure Sensor Using Laser Targeting Of Silicon Carbide, Nabeel A. Riza, Farzan Ghauri, Frank Perez Jan 2007

Wireless Pressure Sensor Using Laser Targeting Of Silicon Carbide, Nabeel A. Riza, Farzan Ghauri, Frank Perez

Faculty Bibliography 2000s

To the best of our knowledge, proposed is the first extreme-environment wireless pressure sensor design using a remoted single-crystal SiC chip within a pressurized capsule. A detailed theoretical analysis of the sensor system is performed, including the SiC chip's mechanical response within the pressure capsule and the pressure measurement technique's optical response based on image demagnification. The remote sensor was experimentally tested at room temperature for pressures up to 41 atm, and the sensor response is consistent with the theoretical analysis. The demonstrated sensor has a current experimental resolution of 1.17 atm with a designed maximum pressure range of 140 …

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Hybrid Analog-Digital Design Microelectromechanical Systems Spectral Processor For Simultaneous Gain Slope And Channel Equalization Controls, Nabeel A. Riza, Syed Azer Reza Jan 2007

Hybrid Analog-Digital Design Microelectromechanical Systems Spectral Processor For Simultaneous Gain Slope And Channel Equalization Controls, Nabeel A. Riza, Syed Azer Reza

Faculty Bibliography 2000s

To the best of our knowledge, this paper demonstrates the first hybrid analog-digital design fiber-optic spectrum processor that can simultaneously provide spectrum gain slope adjustment as well as independent channel equalization attenuation controls.

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Time-Resolved Faraday Rotation Measurements Of Spin Relaxation In Ingaas/Gaas Quantum Dots: Role Of Excess Energy, J. L. Robb, Y. Chen, A. Timmons, K. C. Hall, O. B. Shchekin, D. G. Deppe Jan 2007

Time-Resolved Faraday Rotation Measurements Of Spin Relaxation In Ingaas/Gaas Quantum Dots: Role Of Excess Energy, J. L. Robb, Y. Chen, A. Timmons, K. C. Hall, O. B. Shchekin, D. G. Deppe

Faculty Bibliography 2000s

The authors report measurements of room temperature spin dynamics in InGaAs quantum dots using time-resolved differential transmission and Faraday rotation techniques. They observe an enhancement of the electron spin lifetime by an order of magnitude for direct optical pumping of the quantum dot ground state compared to optical pumping of the GaAs barriers. These findings indicate that the optical excitation conditions can have a critical influence on the spin kinetics, a result which may account for the wide variation of spin lifetimes reported to date. The enhancement in spin lifetime observed here is attributed to the reduction of phonon-mediated spin-flip …

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Geographical Gradients In Diet Affect Population Dynamics Of Canada Lynx, James D. Roth, John D. Marshall, Dennis L. Murray, David M. Nickerson, Todd D. Steury Jan 2007

Geographical Gradients In Diet Affect Population Dynamics Of Canada Lynx, James D. Roth, John D. Marshall, Dennis L. Murray, David M. Nickerson, Todd D. Steury

Faculty Bibliography 2000s

Geographical gradients in the stability of cyclic populations of herbivores and their predators may relate to the degree of specialization of predators. However, such changes are usually associated with transition from specialist to generalist predator species, rather than from geographical variation in dietary breadth of specialist predators. Canada lynx (Lynx canadensis) and snowshoe hare (Lepus americanus) populations undergo cyclic. fluctuations in northern parts of their range, but cycles are either greatly attenuated or lost altogether in the southern boreal forest where prey diversity is higher. We tested the influence of prey specialization on population cycles by measuring the stable carbon …

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Expression Of Cholera Toxin B-Proinsulin Fusion Protein In Lettuce And Tobacco Chloroplasts - Oral Administration Protects Against Development Of Insulitis In Non-Obese Diabetic Mice, Tracey Ruhlman, Raheleh Ahangari, Andrew Devine, Mohtahsem Samsam, Henry Daniell Jan 2007

Expression Of Cholera Toxin B-Proinsulin Fusion Protein In Lettuce And Tobacco Chloroplasts - Oral Administration Protects Against Development Of Insulitis In Non-Obese Diabetic Mice, Tracey Ruhlman, Raheleh Ahangari, Andrew Devine, Mohtahsem Samsam, Henry Daniell

Faculty Bibliography 2000s

Lettuce and tobacco chloroplast transgenic lines expressing the cholera toxin B subunit-human proinsulin (CTB-Pins) fusion protein were generated. CTB-Pins accumulated up to similar to 16% of total soluble protein (TSP) in tobacco and up to similar to 2.5% of TSP in lettuce. Eight milligrams of powdered tobacco leaf material expressing CTB-Pins or, as negative controls, CTB-green fluorescent protein (CTB-GFP) or interferon-GFP (IFN-GFP), or untransformed leaf, were administered orally, each week for 7 weeks, to 5-week-old female non-obese diabetic (NOD) mice. The pancreas of CTB-Pins-treated mice showed decreased infiltration of cells characteristic of lymphocytes (insulitis); insulin-producing beta-cells in the pancreatic islets …

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The Complete Nucleotide Sequence Of The Coffee (Coffea Arabica L.) Chloroplast Genome: Organization And Implications For Biotechnology And Phylogenetic Relationships Amongst Angiosperms, Nalapalli Samson, Michael G. Bausher, Seung-Bum Lee, Robert K. Jansen, Henry Daniell Jan 2007

The Complete Nucleotide Sequence Of The Coffee (Coffea Arabica L.) Chloroplast Genome: Organization And Implications For Biotechnology And Phylogenetic Relationships Amongst Angiosperms, Nalapalli Samson, Michael G. Bausher, Seung-Bum Lee, Robert K. Jansen, Henry Daniell

Faculty Bibliography 2000s

The chloroplast genome sequence of Coffea arabica L., the first sequenced member of the fourth largest family of angiosperms, Rubiaceae, is reported. The genome is 155 189 bp in length, including a pair of inverted repeats of 25 943 bp. Of the 130 genes present, 112 are distinct and 18 are duplicated in the inverted repeat. The coding region comprises 79 protein genes, 29 transfer RNA genes, four ribosomal RNA genes and 18 genes containing introns (three with three exons). Repeat analysis revealed five direct and three inverted repeats of 30 bp or longer with a sequence identity of 90% …

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Mechanical Crystallization Of Fe-Based Amorphous Alloys, Satyajeet Sharma, C. Suryanarayana Jan 2007

Mechanical Crystallization Of Fe-Based Amorphous Alloys, Satyajeet Sharma, C. Suryanarayana

Faculty Bibliography 2000s

Mechanical alloying of a number of blended elemental powders of Fe-based alloy systems containing four or five components was undertaken to determine if amorphous phases could be produced and also to compare the glass-forming ability achieved by mechanical alloying and that obtained by solidification-processing methods. Amorphous phase formation was achieved in all the alloy systems investigated, the time for the amorphous phase formation being a function of the glass-forming ability of the alloy system investigated. However, in some alloy systems it was noted that on milling, beyond the time required for the formation of the amorphous phase, the amorphous phase …

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Criterion For Predicting The Glass-Forming Ability Of Alloys, S. Sharma, R. Vaidyanathan, C. Suryanarayana Jan 2007

Criterion For Predicting The Glass-Forming Ability Of Alloys, S. Sharma, R. Vaidyanathan, C. Suryanarayana

Faculty Bibliography 2000s

Mechanical alloying (MA) of blended elemental powder mixtures of Fe42Zr10X28B20 (X=Al, Co, Ge, Mn, Ni, and Sn) was carried out to determine their glass-forming ability (GFA) (as determined by the time required to form the amorphous phase). During milling, amorphization was achieved in systems with X=Al, Ge, or Ni, but not in the other systems. The GFA could be correlated with the total number of intermetallics present in the constituent binary phase diagrams. Thus, this work offers the equilibrium phase diagram as a predictive tool to determine if amorphization can be achieved by the MA method.

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Fabrication Of Periodic Microstructures On Flexible Polyimide Membranes, D. J. Shelton, J. S. Tharp, G. Zummo, W. R. Folks, G. D. Boreman Jan 2007

Fabrication Of Periodic Microstructures On Flexible Polyimide Membranes, D. J. Shelton, J. S. Tharp, G. Zummo, W. R. Folks, G. D. Boreman

Faculty Bibliography 2000s

Periodic metallic microstructures were fabricated on polyimide membranes. Techniques were developed to maintain flatness of the membrane during processing while still allowing for flexibility in the final structure. For proper functionality of the structures, it was necessary to first fabricate a continuous metallic film and a continuous dielectric layer on top of the flexible substrate, which underlaid the periodic microstructure. Flexibility of the overall structure was maintained by using a polymer as the dielectric layer, which was constrained to have high optical transmission over the infrared wavelength range of 6-14 mu m. Three candidate polymers were evaluated, and their measured …

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Selective Chemical Probe Inhibitor Of Stat3, Identified Through Structure-Based Virtual Screening, Induces Antitumor Activity, Khandaker Siddiquee, Shumin Zhang, Wayne C. Guida, Michelle A. Blaskovich, Benjamin Greedy, Harshani R. Lawrence, M. L. Richard Yip, Richard Jove, Mark M. Mclaughlin, Nicholas J. Lawrence, Said M. Sebti, James Turkson Jan 2007

Selective Chemical Probe Inhibitor Of Stat3, Identified Through Structure-Based Virtual Screening, Induces Antitumor Activity, Khandaker Siddiquee, Shumin Zhang, Wayne C. Guida, Michelle A. Blaskovich, Benjamin Greedy, Harshani R. Lawrence, M. L. Richard Yip, Richard Jove, Mark M. Mclaughlin, Nicholas J. Lawrence, Said M. Sebti, James Turkson

Faculty Bibliography 2000s

S31-201 (NSC 74859) is a chemical probe inhibitor of Stat3 activity, which was identified from the National Cancer Institute chemical libraries by using structure-based virtual screening with a computer model of the Stat3 SH2 domain bound to its Stat3 phosphotyrosine peptide derived from the x-ray crystal structure of the Stat3 beta homodimer. S31-201 inhibits Stat3-Stat3 complex formation and Stat3 DNA-binding and transcriptional activities. Furthermore, S31-201 inhibits growth and induces apoptosis preferentially in tumor cells that contain persistently activated Stat3. Constitutively climerized and active Stat3C and Stat3 SH2 domain rescue tumor cells from S31-201-induced apoptosis. Finally, S31-201 inhibits the expression of …

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Calculation Of Critical Values For Somerville's Fdr Procedures, Paul N. Somerville Jan 2007

Calculation Of Critical Values For Somerville's Fdr Procedures, Paul N. Somerville

Faculty Bibliography 2000s

A Fortran 95 program has been written to calculate critical values for the step-up and step-down FDR procedures developed by Somerville (2004). The program allows for arbitrary selection of number of hypotheses, FDR rate, one- or two-sided hypotheses, common correlation coefficient of the test statistics and degrees of freedom. An MCV (minimum critical value) may be specified, or the program will calculate a specified number of critical values or steps in an FDR procedure. The program can also be used to efficiently ascertain an upper bound to the number of hypotheses which the procedure will reject, given either the values …

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Liquid Mixing Driven Motions Of Floating Macroscopic Objects, Ming Su Jan 2007

Liquid Mixing Driven Motions Of Floating Macroscopic Objects, Ming Su

Faculty Bibliography 2000s

Dropping miscible and low-density organic solvents into water generates translational and rotational motions of floating objects including oil droplets, polymer half spheres, and model boats. The moving speed of the boat at different loads and the force produced by solvent drops are measured. In contrast to motions driven by surface tension of monolayer, the liquid mixing driven motion can be dynamically steered without restriction and continued provided the supply is maintained and the amount of water is large enough. Such motions are the result of Marangoni instability in binary liquid-liquid systems with intentionally produced concentration gradients behind the floating objects.

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Do Coupling Exciton And Oscillation Of Electron-Hole Pair Exist In Neutral And Charged Pi-Dimeric Quinquethiophenes?, Mengtao Sun, Liwei Liu, Hongxing Xu Jan 2007

Do Coupling Exciton And Oscillation Of Electron-Hole Pair Exist In Neutral And Charged Pi-Dimeric Quinquethiophenes?, Mengtao Sun, Liwei Liu, Hongxing Xu

Faculty Bibliography 2000s

Optical physical properties of neutral and charged quinquethiophene monomer, and neutral and cationic pi-dimeric quinquethiophenes were investigated with density functional theory as well as the two dimensional (2D) site (transition density matrix) and three dimensional (3D) cube (transition density and charge difference density) representations, stimulated by the recent experimental report [T. Sakai , J. Am. Chem. Soc. 127, 8082 (2005)]. Transition density shows the orientation and strength of the transition dipole moment of neutral and charged quinquethiophene monomer, and charge difference density reveals the orientation and result of the charge transfer in neutral and charged quinquethiophene monomer. To study if …

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Nonuniform Average Sampling And Reconstruction Of Signals With Finite Rate Of Innovation, Qiyu Sun Jan 2007

Nonuniform Average Sampling And Reconstruction Of Signals With Finite Rate Of Innovation, Qiyu Sun

Faculty Bibliography 2000s

From an average ( ideal) sampling/reconstruction process, the question arises whether the original signal can be recovered from its average (ideal) samples and, if so, how. We consider the above question under the assumption that the original signal comes from a prototypical space modeling signals with a finite rate of innovation, which includes finitely generated shift-invariant spaces, twisted shift-invariant spaces associated with Gabor frames and Wilson bases, and spaces of polynomial splines with nonuniform knots as its special cases. We show that the displayer associated with an average (ideal) sampling/reconstruction process, which has a well-localized average sampler, can be found …

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Optical Modes At The Interface Between Two Dissimilar Discrete Meta-Materials, S. Suntsov, K. G. Makris, D. N. Christodoulides, G. I. Stegeman, R. Morandotti, Maïte Volatier, Vincent Aimez, Richard Arès, Richard E. Rüter, Detlef Kip Jan 2007

Optical Modes At The Interface Between Two Dissimilar Discrete Meta-Materials, S. Suntsov, K. G. Makris, D. N. Christodoulides, G. I. Stegeman, R. Morandotti, Maïte Volatier, Vincent Aimez, Richard Arès, Richard E. Rüter, Detlef Kip

Faculty Bibliography 2000s

We have studied theoretically and experimentally the properties of optical surface modes at the hetero-interface between two meta-materials. These meta-materials consisted of two 1D AlGaAs waveguide arrays with different band structures.

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Fabrication And Characterization Of Three-Dimensional Copper Metallodielectric Photonic Crystals, Amir Tal, Yun-Sheng Chen, Henry E. Williams, Raymond C. Rumpf, Stephen M. Kuebler Jan 2007

Fabrication And Characterization Of Three-Dimensional Copper Metallodielectric Photonic Crystals, Amir Tal, Yun-Sheng Chen, Henry E. Williams, Raymond C. Rumpf, Stephen M. Kuebler

Faculty Bibliography 2000s

Three-dimensional metallodielectric photonic crystals were created by fabricating a micron-scale polymeric template using multi-photon direct laser writing (DLW) in SU-8 and conformally and selectively coating the template with copper (Cu) via nanoparticle-nucleated electroless metallization. This process deposits a uniform metal coating, even deep within a lattice, because it is not directional like sputter-coating or evaporative deposition. Infrared reflectance spectra show that upon metallization the optical behavior transitions fully from a dielectric photonic crystal to that of a metal photonic crystal (MPC). After depositing 50 nm of Cu, the MPCs exhibit a strong plasmonic stop band having reflectance greater than 80% …

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Thermal Stability Of Cdzno/Zno Multi-Quantum-Wells, A. V. Thompson, C. Boutwell, J. W. Mares, W. V. Schoenfeld, A. Osinsky, B. Hertog, J. Q. Xie, S. J. Pearton, D. P. Norton Jan 2007

Thermal Stability Of Cdzno/Zno Multi-Quantum-Wells, A. V. Thompson, C. Boutwell, J. W. Mares, W. V. Schoenfeld, A. Osinsky, B. Hertog, J. Q. Xie, S. J. Pearton, D. P. Norton

Faculty Bibliography 2000s

The thermal stability of CdZnO/ZnO multi-quantum-well (MQW) structures was studied using rapid thermal annealing in nitrogen from 300 to 750 degrees C. Photoluminescence (PL) emission from the MQWs was studied while varying the annealing temperature and time. For 15 min annealings, the PL center wavelength showed a 7 nm reduction for temperatures up to 650 degrees C. Above 650 degrees C, the wavelength changed rapidly, with a 50 nm reduction at 750 degrees C. Annealing at 700 degrees C for up to 20 min produced a systematic reduction in PL wavelength up to 39 nm. The data suggest that CdZnO/ZnO …

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On The Origin Of The 1/F Noise In Shallow Germanium P(+)-N Junctions, R. M. Todi, S. Sonde, E. Simoen, C. Claeys, K. B. Sundaram Jan 2007

On The Origin Of The 1/F Noise In Shallow Germanium P(+)-N Junctions, R. M. Todi, S. Sonde, E. Simoen, C. Claeys, K. B. Sundaram

Faculty Bibliography 2000s

The low-frequency noise of shallow germanium p(+)-n junctions is studied, for diodes with or without a nickel-germanide Ohmic contact. It is shown that the application of NiGe not only reduces the series resistance, resulting in a higher forward current, but also results in a lower 1/f noise at forward bias. From the observed geometry dependence, it is concluded that germanidation suppresses the 1/f noise generated in the series resistance, leaving surface-state-assisted generation-recombination at the junction perimeter as the dominant flicker noise source.

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Hospital Outpatient Perceptions Of The Physical Environment Of Waiting Areas: The Role Of Patient Characteristics On Atmospherics In One Academic Medical Center, Chun-Yen Tsai, Mu-Chia Wang, Wei-Tsen Liao, Jui-Heng Lu, Pi-Hung Sun, Blossom Yen-Ju Lin, Gerald-Mark Breen Jan 2007

Hospital Outpatient Perceptions Of The Physical Environment Of Waiting Areas: The Role Of Patient Characteristics On Atmospherics In One Academic Medical Center, Chun-Yen Tsai, Mu-Chia Wang, Wei-Tsen Liao, Jui-Heng Lu, Pi-Hung Sun, Blossom Yen-Ju Lin, Gerald-Mark Breen

Faculty Bibliography 2000s

Background: This study examines hospital outpatient perceptions of the physical environment of the outpatient waiting areas in one medical center. The relationship of patient characteristics and their perceptions and needs for the outpatient waiting areas are also examined. Method: The examined medical center consists of five main buildings which house seventeen primary waiting areas for the outpatient clinics of nine medical specialties: 1) Internal Medicine; 2) Surgery; 3) Ophthalmology; 4) Obstetrics-Gynecology and Pediatrics; 5) Chinese Medicine; 6) Otolaryngology; 7) Orthopedics; 8) Family Medicine; and 9) Dermatology. A 15-item structured questionnaire was developed to rate patient satisfaction covering the four dimensions …

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Optical Absorption, Depolarization, And Scatter Of Epitaxial Single-Crystal Chemical-Vapor-Deposited Diamond At 1.064 Mu M, Giorgio Turri, Ying Chen, Michael Bass, David Orchard, James E. Butler, S. Magana, T. Feygelson, D. Thiel, K. Fourspring, Randle V. Dewees, Jean M. Bennett, Joni Pentony, Samantha Hawkins, Meghan Baronowski, Andrew Guenthner, Michael D. Seltzer, Daniel C. Harris, C. Martin Stickley Jan 2007

Optical Absorption, Depolarization, And Scatter Of Epitaxial Single-Crystal Chemical-Vapor-Deposited Diamond At 1.064 Mu M, Giorgio Turri, Ying Chen, Michael Bass, David Orchard, James E. Butler, S. Magana, T. Feygelson, D. Thiel, K. Fourspring, Randle V. Dewees, Jean M. Bennett, Joni Pentony, Samantha Hawkins, Meghan Baronowski, Andrew Guenthner, Michael D. Seltzer, Daniel C. Harris, C. Martin Stickley

Faculty Bibliography 2000s

Epitaxial single-crystal chemical-vapor-deposited diamond with (100) crystal orientation is obtained from Element Six (Ascot, United Kingdom) and Apollo Diamond (Boston, Massachusetts). Both companies supply 5 x 5-mm squares with thicknesses of 0.35 to 1.74 mm. Element Six also provides disks with a state of the art diameter of 10 to 11 mm and a thickness of 1.0 mm. The absorption coefficient measured by laser calorimetry at 1.064 mu m is 0.003 cm(-1) for squares from Element Six and 0.07 cm(-1) for squares from Apollo. One Apollo specimen has an absorption coefficient near those of the Element Six material. Absorption coefficients …

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Ppar Alpha L162v Underlies Variation In Serum Triglycerides And Subcutaneous Fat Volume In Young Males, Julieta Uthurralt, Heather Gordish-Dressman, Meg Bradbury, Carolina Tesi-Rocha, Joseph Devaney, Brennan Harmon, Erica K. Reeves, Cinzia Brandoli, Barbara C. Hansen, Richard L. Seip, Paul D. Thompson, Thomas B. Price, Theodore J. Angelopoulos, Priscilla M. Clarkson, Niall M. Moyna, Linda S. Pescatello, Paul S. Visich, Robert F. Zoeller, Paul M. Gordon, Eric P. Hoffman Jan 2007

Ppar Alpha L162v Underlies Variation In Serum Triglycerides And Subcutaneous Fat Volume In Young Males, Julieta Uthurralt, Heather Gordish-Dressman, Meg Bradbury, Carolina Tesi-Rocha, Joseph Devaney, Brennan Harmon, Erica K. Reeves, Cinzia Brandoli, Barbara C. Hansen, Richard L. Seip, Paul D. Thompson, Thomas B. Price, Theodore J. Angelopoulos, Priscilla M. Clarkson, Niall M. Moyna, Linda S. Pescatello, Paul S. Visich, Robert F. Zoeller, Paul M. Gordon, Eric P. Hoffman

Faculty Bibliography 2000s

Background: Of the five sub-phenotypes defining metabolic syndrome, all are known to have strong genetic components ( typically 50 - 80% of population variation). Studies defining genetic predispositions have typically focused on older populations with metabolic syndrome and/or type 2 diabetes. We hypothesized that the study of younger populations would mitigate many confounding variables, and allow us to better define genetic predisposition loci for metabolic syndrome. Methods: We studied 610 young adult volunteers ( average age 24 yrs) for metabolic syndrome markers, and volumetric MRI of upper arm muscle, bone, and fat pre- and post-unilateral resistance training. Results: We found …

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Efficacy, Pharmacokinetics, And Metabolism Of Tetrahydroquinoline Inhibitors Of Plasmodium Falciparum Protein Farnesyltransferase, Wesley C. Voorhis, Kasey L. Rivas, Pravin Bendale, Laxman Nallan, Carolyn Hornéy, Lynn K. Barrett, Kevin D. Bauer, Brian P. Smart, Sudha Ankala, Oliver Hucke, Christophe L. M. J. Verlinde, Debopam Chakrabarti, Corey Strickland, Kohei Yokoyama, Frederick S. Buckner, Andrew D. Hamilton, David K. Williams, Louis J. Lombardo, David Floyd, Michael H. Gelb Jan 2007

Efficacy, Pharmacokinetics, And Metabolism Of Tetrahydroquinoline Inhibitors Of Plasmodium Falciparum Protein Farnesyltransferase, Wesley C. Voorhis, Kasey L. Rivas, Pravin Bendale, Laxman Nallan, Carolyn Hornéy, Lynn K. Barrett, Kevin D. Bauer, Brian P. Smart, Sudha Ankala, Oliver Hucke, Christophe L. M. J. Verlinde, Debopam Chakrabarti, Corey Strickland, Kohei Yokoyama, Frederick S. Buckner, Andrew D. Hamilton, David K. Williams, Louis J. Lombardo, David Floyd, Michael H. Gelb

Faculty Bibliography 2000s

New antimalarials are urgently needed. We have shown that tetrahydroquinoline (THQ) protein farnesyltransferase (PFr) inhibitors (PFTIs) are effective against the Plasmodium falciparum PFr and are effective at killing P. falciparum in vitro. Previously described THQ PFTIs had limitations of poor oral bioavailability and rapid clearance from the circulation of rodents. In this paper, we validate both the Caco-2 cell permeability model for predicting THQ intestinal absorption and the in vitro liver microsome model for predicting THQ clearance in vivo. Incremental improvements in efficacy, oral absorption, and clearance rate were monitored by in vitro tests; and these tests were followed up …

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Electric-Pulse-Induced Reversible Resistance In Doped Zinc Oxide Thin Films, M. Villafuerte, S. P. Heluani, G. Juàrez, G. Simonelli, G. Braunstein, S. Duhalde Jan 2007

Electric-Pulse-Induced Reversible Resistance In Doped Zinc Oxide Thin Films, M. Villafuerte, S. P. Heluani, G. Juàrez, G. Simonelli, G. Braunstein, S. Duhalde

Faculty Bibliography 2000s

Nonvolatile, electric-pulse-induced resistance switching is reported on S and Co doped ZnO thin films deposited on different substrates using magnetron sputtering and laser ablation. Two resistance states were obtained by applying voltage pulses of different polarity. The switching was observed regardless of the substrate, dopant species, or microstructure of the samples. In the Co doped ZnO samples, the two resistance states are remarkably stable and uniform.

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Surface Elastic Properties Of Porous Nanosilica Coatings By Scanning Force Microscopy, A. Vincent, S. Babu, S. Seal Jan 2007

Surface Elastic Properties Of Porous Nanosilica Coatings By Scanning Force Microscopy, A. Vincent, S. Babu, S. Seal

Faculty Bibliography 2000s

Surface elastic properties of sol-gel derived porous nanosilica optical coatings were determined using scanning force microscopy. Silica nanocoatings prepared under acid and base catalyzed sol-gel process exhibited varying surface morphology, particle size and porosity. Force-distance spectroscopy measurements were conducted on these coatings using scanning force microscopy, and their elastic moduli were obtained by applying Hertz model. The elastic modulus of the coatings varied from 2.4 to 13.4 GPa depending on the nature and concentration of the catalyst used.

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Short-Term Relationship Between Solar Irradiances And Equatorial Peak Electron Densities, X. Wang, R. Eastes, B. W. Reinisch, S. Bailey, C. E. Valladares, T. Woods Jan 2007

Short-Term Relationship Between Solar Irradiances And Equatorial Peak Electron Densities, X. Wang, R. Eastes, B. W. Reinisch, S. Bailey, C. E. Valladares, T. Woods

Faculty Bibliography 2000s

[1] The short-term relationship of the equatorial peak electron density and the solar short-wavelength irradiance is examined using foF2 observations from Jicamarca, Peru and recent solar irradiance measurements from satellites. Solar soft X-ray measurements from both the Student Nitric Oxide Explorer (SNOE) ( 1998 - 2000) and Thermosphere Ionosphere Mesosphere Energetics Dynamics ( TIMED) ( 2002 - 2004) satellites as well as extreme ultraviolet (EUV) measurements from the TIMED satellite are used. Soft X-rays show similar or higher correlation with foF2 at short timescales ( 27 days or less) than EUV does, although the EUV correlation is higher for longer …

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Thermal Conductance Across Grain Boundaries In Diamond From Molecular Dynamics Simulation, Taku Watanabe, Boris Ni, Simon R. Phillpot, Patrick K. Schelling, Pawel Keblinski Jan 2007

Thermal Conductance Across Grain Boundaries In Diamond From Molecular Dynamics Simulation, Taku Watanabe, Boris Ni, Simon R. Phillpot, Patrick K. Schelling, Pawel Keblinski

Faculty Bibliography 2000s

We determine the dependence of the interfacial conductance on twist angle for (001) symmetric twist grain boundaries (GBs) in diamond. We find that the conductances are extremely large, ranging from 7.7 to 17.6 GW/m(2) K. Nevertheless, when normalized to the single-crystal conductivity, the resulting Kapitza lengths are actually longer in diamond than in Si, indicating that the diamond GBs are relatively worse conductors of heat. This result is consistent with the poorer bonding across the diamond grain boundaries. We find that the interfacial conductance and Kapitza length can be well fitted by an extended Read-Shockley model.

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Phonon Characteristics And Photoluminescence Of Bamboo Structured Silicon-Doped Boron Nitride Multiwall Nanotubes, Shifeng Xu, Yi Fan, Jingsong Luo, Ligong Zhang, Wenquan Wang, Bin Yao, Linan An Jan 2007

Phonon Characteristics And Photoluminescence Of Bamboo Structured Silicon-Doped Boron Nitride Multiwall Nanotubes, Shifeng Xu, Yi Fan, Jingsong Luo, Ligong Zhang, Wenquan Wang, Bin Yao, Linan An

Faculty Bibliography 2000s

Bamboo structured silicon-doped boron nitride multiwall nanotubes are synthesized via catalyst-assisted pyrolysis of a boron-containing polymeric precursor. The nanotubes are characterized using transmission electron microscopy, x-ray diffraction, Raman, and Fourier-transformed infrared spectroscope. The results suggest that the Si dopants cause significant changes in the structure and phonon characteristics of the nanotubes as compared to pure boron nitride nanotubes. A broad photoluminescence band ranging between 500 and 800 nm is observed from the nanotubes, which is attributed to Si dopants. Study on temperature dependence of emission intensity suggests that the thermal activation energy of the nonradiative recombination process is 35 meV.

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Time-Resolved Ducting Of Atmospheric Acoustic-Gravity Waves By Analysis Of The Vertical Energy Flux, Yonghui Yu, Michael P. Hickey Jan 2007

Time-Resolved Ducting Of Atmospheric Acoustic-Gravity Waves By Analysis Of The Vertical Energy Flux, Yonghui Yu, Michael P. Hickey

Faculty Bibliography 2000s

A new 2-D time-dependent model is used to simulate the propagation of an acoustic-gravity wave packet in the atmosphere. A Gaussian tropospheric heat source is assumed with a forcing period of 6.276 minutes. The atmospheric thermal structure creates three discrete wave ducts in the stratosphere, mesosphere, and lower thermosphere, respectively. The horizontally averaged vertical energy flux is derived over altitude and time in order to examine the time-resolved ducting. This ducting is characterized by alternating upward and downward energy fluxes within a particular duct, which clearly show the reflections occurring from the duct boundaries. These ducting simulations are the first …

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Simulated Ducting Of High-Frequency Atmospheric Gravity Waves In The Presence Of Background Winds, Yonghui Yu, Michael P. Hickey Jan 2007

Simulated Ducting Of High-Frequency Atmospheric Gravity Waves In The Presence Of Background Winds, Yonghui Yu, Michael P. Hickey

Faculty Bibliography 2000s

A new nonlinear and time-dependent model is used to derive the total perturbation energy flux of two gravity wave packets propagating from the troposphere to the lower thermosphere. They are excited by a heat source and respectively propagate in an eastward and westward direction in the presence of a zonal wind. Analysis of the refractive index, the power spectra and the total perturbation energy flux allows us to correctly interpret the ducting characteristics of these two wave packets. In our study the wind acts as a directional filter to the wave propagations and causes noticeable spectral variations at higher altitudes. …

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