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Lattice-Stiffening Transition In Copolymer Films Of Vinylidene Fluoride (70%) With Trifluoroethylene (30%), C. N. Borca, S. Adenwalla, Jaewu Choi, P. T. Sprunger, Stephen Ducharme, Lee Robertson, S. P. Palto, Jianglai Liu, Matt Poulsen, V. M. Fridkin, H. You, P. A. Dowben Jan 1999

Lattice-Stiffening Transition In Copolymer Films Of Vinylidene Fluoride (70%) With Trifluoroethylene (30%), C. N. Borca, S. Adenwalla, Jaewu Choi, P. T. Sprunger, Stephen Ducharme, Lee Robertson, S. P. Palto, Jianglai Liu, Matt Poulsen, V. M. Fridkin, H. You, P. A. Dowben

Faculty Publications

We report the discovery of a compressibility phase transition at 160 K in crystalline copolymer films of vinylidene fluoride (70%) with trifluoroethylene (30%). This phase transition is distinct from the known bulk ferroelectric-paraelectric phase transition at 353 K and surface ferroelectric phase transition at 295 K. The new phase transition is characterized by an increase in the effective Debye temperature from 48 to 245 K along the 〈010〉 direction as the temperature falls below 160 K. This phase transition is evident in neutron scattering, x-ray diffraction, angle-resolved photoemission, and in the dipole active phonon modes in electron energy-loss spectroscopy. © …

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Ultrasonic Attenuation In Clean D-Wave Superconductors, I. Vekhter, E. J. Nicol, J. P. Carbotte Jan 1999

Ultrasonic Attenuation In Clean D-Wave Superconductors, I. Vekhter, E. J. Nicol, J. P. Carbotte

Faculty Publications

We consider the attenuation of longitudinal ultrasonic waves in a clean two-dimensional d-wave superconductor. We show that the attenuation coefficient is linear in temperature at low temperatures for all in-plane directions of the propagation of the ultrasound, and that the coefficient of the linear term can be used to determine the parameters crucial for the low-temperature transport in these compounds. © 1999 American Physical Society.

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Anisotropic Thermodynamics Of (Formula Presented)-Wave Superconductors In The Vortex State, I. Vekhter Jan 1999

Anisotropic Thermodynamics Of (Formula Presented)-Wave Superconductors In The Vortex State, I. Vekhter

Faculty Publications

We show that the density of states and the thermodynamic properties of a two-dimensional (Formula presented)-wave superconductor in the vortex state with applied magnetic field H in the plane depend on the angle between H and the order-parameter nodes. Within a semiclassical treatment of the extended quasiparticle states, we obtain fourfold oscillations of the specific heat, measurement of which provides a simple probe of gap symmetry. The frequency dependence of the density of states and the temperature dependence of thermodynamic properties obey different power laws for field in the nodal and antinodal direction. The fourfold pattern is changed to twofold …

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Quasiparticle Thermal Conductivity In The Vortex State Of High- Tccuprates, I. Vekhter, A. Houghton Jan 1999

Quasiparticle Thermal Conductivity In The Vortex State Of High- Tccuprates, I. Vekhter, A. Houghton

Faculty Publications

We present the results of a microscopic calculation of the longitudinal thermal conductivity, κxx, of a d-wave superconductor in the mixed state. Our results show an increase in the thermal conductivity with the applied field at low temperatures and a decrease followed by a nearly field independent κxx(H) at higher temperatures, in qualitative agreement with the experimental results. We discuss the relationship between the slope of the superconducting gap and the plateau in κxx(H). © 1999 The American Physical Society.

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Quasiparticle Transport In The Vortex State Of D-Wave Superconductors, I. Vekhter Jan 1999

Quasiparticle Transport In The Vortex State Of D-Wave Superconductors, I. Vekhter

Faculty Publications

We calculate the magnetic field and temperature dependence of the Raman response, superfluid density, and the NMR relaxation rate in the vortex state of a d-wave superconductor arising from the Doppler energy shift of extended quasiparticle states. Our results are valid both at low temperatures, where we observe scaling with variable (Formula presented) and obtain an explicit form of the scaling functions, and beyond this region. We derive a universal frequency-dependent scaling relation for the Raman intensity, and discuss the breakdown of the single relaxation rate approach to the NMR response. © 1999 The American Physical Society.

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Arch For Antihelium In Cosmic Rays, J. Alcaraz, D. Alvisi, B. Alpat, G. Ambrosi, H. Anderhub, L. Ao, A. Arefiev, P. Azzarello, E. Babucci, L. Baldini, M. Basile, D. Barancourt, F. Barao, G. Barbier, G. Barreira, R. Battiston, R. Becker, U. Becker, L. Bellagamba, P. Béné, J. Berdugo, P. Berges, B. Bertucci, A. Biland, S. Bizzaglia, S. Blasko, G. Boella, M. Bourquin, G. Bruni, M. Buenerd, J. D. Burger, W. J. Burger, X. D. Cai Jan 1999

Arch For Antihelium In Cosmic Rays, J. Alcaraz, D. Alvisi, B. Alpat, G. Ambrosi, H. Anderhub, L. Ao, A. Arefiev, P. Azzarello, E. Babucci, L. Baldini, M. Basile, D. Barancourt, F. Barao, G. Barbier, G. Barreira, R. Battiston, R. Becker, U. Becker, L. Bellagamba, P. Béné, J. Berdugo, P. Berges, B. Bertucci, A. Biland, S. Bizzaglia, S. Blasko, G. Boella, M. Bourquin, G. Bruni, M. Buenerd, J. D. Burger, W. J. Burger, X. D. Cai

Faculty Publications

The Alpha Magnetic Spectrometer (AMS) was flown on the space shuttle Discovery during flight STS-91 in a 51.7° orbit at altitudes between 320 and 390km. A total of 2.86 × 106 helium nuclei were observed in the rigidity range 1 to 140 GV. No antihelium nuclei were detected at any rigidity. An upper limit on the flux ratio of antihelium to helium of < 1.1 × 10-6 is obtained. © 1999 Published by Elsevier Science B.V. All rights reserved.

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Measurement Of The Solar Neutrino Capture Rate With Gallium Metal, J. N. Abdurashitov, V. N. Gavrin, S. V. Girin, V. V. Gorbachev, T. V. Ibragimova, A. V. Kalikhov, N. G. Khairnasov, T. V. Knodel, I. N. Mirmov, A. A. Shikhin, E. P. Veretenkin, V. M. Vermul, V. E. Yants, G. T. Zatsepin, T. J. Bowles, W. A. Teasdale, D. L. Wark, M. L. Cherry, J. S. Nico, B. T. Cleveland, R. Davis, K. Lande, P. S. Wildenhain, S. R. Elliott, J. F. Wilkerson Jan 1999

Measurement Of The Solar Neutrino Capture Rate With Gallium Metal, J. N. Abdurashitov, V. N. Gavrin, S. V. Girin, V. V. Gorbachev, T. V. Ibragimova, A. V. Kalikhov, N. G. Khairnasov, T. V. Knodel, I. N. Mirmov, A. A. Shikhin, E. P. Veretenkin, V. M. Vermul, V. E. Yants, G. T. Zatsepin, T. J. Bowles, W. A. Teasdale, D. L. Wark, M. L. Cherry, J. S. Nico, B. T. Cleveland, R. Davis, K. Lande, P. S. Wildenhain, S. R. Elliott, J. F. Wilkerson

Faculty Publications

The solar neutrino capture rate measured by the Russian-American Gallium Experiment (SAGE) on metallic gallium during the period January 1990 through December 1997 is [Formula Presented] SNU, where the uncertainties are statistical and systematic, respectively. This represents only about half of the predicted standard solar model rate of 129 SNU. All the experimental procedures, including extraction of germanium from gallium, counting of [Formula Presented] and data analysis, are discussed in detail. © 1999 The American Physical Society.

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Measurement Of The Response Of A Gallium Metal Solar Neutrino Experiment To Neutrinos From A [Formula Presented] Source, J. N. Abdurashitov, V. N. Gavrin, S. V. Girin, V. V. Gorbachev, T. V. Ibragimova, A. V. Kalikhov, N. G. Khairnasov, T. V. Knodel, V. N. Kornoukhov, I. N. Mirmov, A. A. Shikhin, E. P. Veretenkin, V. M. Vermul, V. E. Yants, G. T. Zatsepin, Yu S. Khomyakov, A. V. Zvonarev, T. J. Bowles, J. S. Nico, W. A. Teasdale, D. L. Wark, M. L. Cherry, V. N. Karaulov, V. L. Levitin, V. I. Maev, P. I. Nazarenko, V. S. Shkol’Nik, N. V. Skorikov, B. T. Cleveland, T. Daily, R. Davis, K. Lande, C. K. Lee Jan 1999

Measurement Of The Response Of A Gallium Metal Solar Neutrino Experiment To Neutrinos From A [Formula Presented] Source, J. N. Abdurashitov, V. N. Gavrin, S. V. Girin, V. V. Gorbachev, T. V. Ibragimova, A. V. Kalikhov, N. G. Khairnasov, T. V. Knodel, V. N. Kornoukhov, I. N. Mirmov, A. A. Shikhin, E. P. Veretenkin, V. M. Vermul, V. E. Yants, G. T. Zatsepin, Yu S. Khomyakov, A. V. Zvonarev, T. J. Bowles, J. S. Nico, W. A. Teasdale, D. L. Wark, M. L. Cherry, V. N. Karaulov, V. L. Levitin, V. I. Maev, P. I. Nazarenko, V. S. Shkol’Nik, N. V. Skorikov, B. T. Cleveland, T. Daily, R. Davis, K. Lande, C. K. Lee

Faculty Publications

The neutrino capture rate measured by the Russian-American Gallium Experiment is well below that predicted by solar models. To check the response of this experiment to low-energy neutrinos, a 517 kCi source of [Formula Presented]Cr was produced by irradiating 512.7 g of 92.4%-enriched [Formula Presented]Cr in a high-flux fast neutron reactor. This source, which mainly emits monoenergetic 747-keV neutrinos, was placed at the center of a 13.1 ton target of liquid gallium and the cross section for the production of [Formula Presented]Ge by the inverse beta decay [Formula Presented] was measured to be [Formula Presented] The ratio of this cross …

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Quantum-Path Analysis And Phase Matching Of High-Order Harmonic Generation And High-Order Frequency Mixing Processes In Strong Laser Fields, Philippe Balcou, Anne S. Dederichs, Mette B. Gaarde, Anne L'Huillier Jan 1999

Quantum-Path Analysis And Phase Matching Of High-Order Harmonic Generation And High-Order Frequency Mixing Processes In Strong Laser Fields, Philippe Balcou, Anne S. Dederichs, Mette B. Gaarde, Anne L'Huillier

Faculty Publications

We study phase-matching conditions for high-order harmonic generation as well as high-order sum- and difference-frequency mixing processes in strong laser fields, using a graphical approach described in Balcou et al (1997 Phys. Rev. A 55 3204-10). This method is based on the analysis of the different quantum paths that contribute, with different phase properties, to the single-atom response. We propose a simple numerical method to disentangle the quantum paths contributing to the generation process. We present graphical maps of the phase matching around the laser focus, which allow one to predict the geometries that optimize the conversion efficiency of the …

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High Harmonic Generation At Long Wavelengths, B. Sheehy, J. D.D. Martin, L. F. Di Mauro, P. Agostini, K. J. Schafer, M. B. Gaarde, K. C. Kulander Jan 1999

High Harmonic Generation At Long Wavelengths, B. Sheehy, J. D.D. Martin, L. F. Di Mauro, P. Agostini, K. J. Schafer, M. B. Gaarde, K. C. Kulander

Faculty Publications

High harmonic radiation spectra up to 19th order in alkali metal vapors excited by an intense, picosecond mid-infrared (3-4 μm) laser are reported and compared to theory. The strong-field dynamics in the alkali metal atoms exhibit significant differences from all previously studied systems due to the strong coupling between their ground and first excited states. © 1999 The American Physical Society.

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Temporal Coherence Of High-Order Harmonics, C. Lyngå, M. B. Gaarde, C. Delfin, M. Bellini, T. W. Hänsch, A. L’ Huillier, C. G. Wahlström Jan 1999

Temporal Coherence Of High-Order Harmonics, C. Lyngå, M. B. Gaarde, C. Delfin, M. Bellini, T. W. Hänsch, A. L’ Huillier, C. G. Wahlström

Faculty Publications

Systematic studies of the temporal coherence properties of high-order harmonic radiation are presented. These complement our previous investigations [Bellini et al., Phys. Rev. Lett. 81, 297 (1998)], where we showed the separation of the far-field pattern of high-order harmonics into two distinct spatial regions with different coherence times. Here we show how the coherence time of the inner and outer regions changes as a function of the harmonic order, the laser intensity, and the focusing conditions. Good agreement with the predictions of the semiclassical model of harmonic generation is obtained. © 1999 The American Physical Society.

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Controlling Phase Matching Of High-Order Harmonic Generation By Manipulating The Fundamental Field, Lena Roos, Eric Constant, Eric Mével, Philippe Balcou, Dominique Descamps, Mette B. Gaarde, Alexandre Valette, Romain Haroutunian, Anne L’Huillier Jan 1999

Controlling Phase Matching Of High-Order Harmonic Generation By Manipulating The Fundamental Field, Lena Roos, Eric Constant, Eric Mével, Philippe Balcou, Dominique Descamps, Mette B. Gaarde, Alexandre Valette, Romain Haroutunian, Anne L’Huillier

Faculty Publications

We study experimentally how to control and improve phase matching of high-order harmonic generation. We use a birefringent lens and a birefringent compensator to obtain a fundamental laser pulse (150 fs, 800 nm, ∼4 mJ) with two foci separated by 6.2 mm along the propagation axis and with a controllable phase delay between the polarizations along the optic axes of the birefringent optical components. This enables us to enhance the high-order harmonic conversion efficiency for the high-order harmonics in neon to [Formula Presented] a factor of 4 higher compared to a single-focus setup in similar conditions. The enhancement is achieved …

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Spatiotemporal Separation Of High Harmonic Radiation Into Two Quantum Path Components, M. B. Gaarde, F. Salin, E. Constant, Ph Balcou, K. J. Schafer, K. C. Kulander, A. L’Huillier Jan 1999

Spatiotemporal Separation Of High Harmonic Radiation Into Two Quantum Path Components, M. B. Gaarde, F. Salin, E. Constant, Ph Balcou, K. J. Schafer, K. C. Kulander, A. L’Huillier

Faculty Publications

We present a spatiotemporal analysis of high harmonic generation, showing evidence for the presence of several quantum path contributions to the atomic dipole moment. We show that the harmonic radiation can largely be described as a sum of two fields having a phase proportional to the intensity of the generating field. We compare our results to recent experimental results demonstrating this separation [M. Bellini et al., Phys. Rev. Lett. 81, 297 (1998)]. We show how the temporal and spatial coherence properties are influenced by this effect, and discuss how it could be used to obtain better control of the generated …

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Measurement Of The Solar Neutrino Capture Rate By Sage And Implications For Neutrino Oscillations In Vacuum, J. N. Abdurashitov, T. J. Bowles, M. L. Cherry, B. T. Cleveland, R. Davis, S. R. Elliott, V. N. Gavrin, S. V. Girin, V. V. Gorbachev, T. V. Ibragimova, A. V. Kalikhov, N. G. Khairnasov, T. V. Knodel, K. Lande, I. N. Mirmov, J. S. Nico, A. A. Shikhin, W. A. Teasdale, E. P. Veretenkin, V. M. Vermul, D. L. Wark, P. S. Wildenhain, J. F. Wilkerson, V. E. Yants, G. T. Zatsep Jan 1999

Measurement Of The Solar Neutrino Capture Rate By Sage And Implications For Neutrino Oscillations In Vacuum, J. N. Abdurashitov, T. J. Bowles, M. L. Cherry, B. T. Cleveland, R. Davis, S. R. Elliott, V. N. Gavrin, S. V. Girin, V. V. Gorbachev, T. V. Ibragimova, A. V. Kalikhov, N. G. Khairnasov, T. V. Knodel, K. Lande, I. N. Mirmov, J. S. Nico, A. A. Shikhin, W. A. Teasdale, E. P. Veretenkin, V. M. Vermul, D. L. Wark, P. S. Wildenhain, J. F. Wilkerson, V. E. Yants, G. T. Zatsep

Faculty Publications

The Russian-American solar neutrino experiment has measured the capture rate of neutrinos on metallic gallium in a radiochemical experiment at the Baksan Neutrino Observatory. Eight years of measurement give the result 67.2-7.0-3.0+7.2+3.5solar neutrino units, where the uncertainties are statistical and systematic, respectively. The restrictions these results impose on vacuum neutrino oscillation parameters are given. © 1999 The American Physical Society.

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Period-Doubling Behavior In Frontal Polymerization Of Multifunctional Acrylates, Jonathan Masere, Felicia Stewart, Timothy Meehan, John A. Pojman Jan 1999

Period-Doubling Behavior In Frontal Polymerization Of Multifunctional Acrylates, Jonathan Masere, Felicia Stewart, Timothy Meehan, John A. Pojman

Faculty Publications

Front dynamics in the frontal polymerization of two multifunctional acrylate monomers, 1,6-hexanediol diacrylate (HDDA) and trimethylolpropane ethoxylate triacrylate (TMPTA), with Lupersol 231 [1,1-di(t-butylperoxy)-3,3,5-trimethylcyclohexane] as the initiator, are studied. In most frontal polymerization systems, the dynamics are associated with a planar front propagating through the sample. However, in some cases, front behavior can be altered: the front becomes nonplanar characterized by complex patterns like spin modes and pulsations. To determine how these periodic and aperiodic modes arise, reactant solutions consisting of HDDA diluted with diethyl phthalate (DEP) and TMPTA diluted with dimethyl sulfoxide (DMSO) were used in the study. In the …

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Overview: Nonlinear Dynamics Related To Polymeric Systems, Irving R. Epstein, John A. Pojman Jan 1999

Overview: Nonlinear Dynamics Related To Polymeric Systems, Irving R. Epstein, John A. Pojman

Faculty Publications

No abstract provided.

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Spin State And Ligand Dissociation In [Cpcol2] Complexes (L = Ph3, H2C=Ch2): A Computational Study, Rinaldo Poli, Kevin M. Smith Jan 1999

Spin State And Ligand Dissociation In [Cpcol2] Complexes (L = Ph3, H2C=Ch2): A Computational Study, Rinaldo Poli, Kevin M. Smith

Faculty Publications

The relative energies of [CpCoL] compounds (L = PH3, H2C= CH2) were calculated at the DFT/B3LYP level of theory. The triplet spin state was found to be favored over the singlet by between 33.0 and 21.0 kcal mol-1 for both fixed and optimized geometries. The basis set size was found to be important for the energy calculations, particularly when the energetics of ligand dissociation was examined. The role of the triplet spin state in facilitating the ligand dissociation process is discussed.

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Separation Of Saturated And Unsaturated Free Fatty Acids Using Capillary Electrophoresis With Indirect Photometric Detection, F. Haddadian, S. A. Shamsi, I. M. Warner Jan 1999

Separation Of Saturated And Unsaturated Free Fatty Acids Using Capillary Electrophoresis With Indirect Photometric Detection, F. Haddadian, S. A. Shamsi, I. M. Warner

Faculty Publications

The capillary zone electrophoresis separation of various mixtures of saturated and unsaturated free fatty acids (FFAs) is performed using adenosine monophosphate (AMP) as an indirect photometric detection reagent. The presence of Brij in the electrolyte and a temperature of 40°C in the running buffer are required to improve solubility of the very long chain FFAs. The separation of C12-C31 differing by only one carbon is achieved using N-methylformamide (NMF)-dioxane (3:2), 40mM Tris, 2.5mM AMP, and 0.5% (w/v) Brij in approximately 40 min. However, baseline resolution of unsaturated isomers of FFAs (C14-C22) requires the presence of water, because water enhances the …

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How Do Algae Concentrate Co2 To Increase The Efficiency Of Photosynthetic Carbon Fixation?, James V. Moroney, Aravind Somanchi Jan 1999

How Do Algae Concentrate Co2 To Increase The Efficiency Of Photosynthetic Carbon Fixation?, James V. Moroney, Aravind Somanchi

Faculty Publications

No abstract provided.

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Zim1, A Maternally Expressed Mouse Kruppel-Type Zinc-Finger Gene Located In Proximal Chromosome 7, Joomyeong Kim, Xiaochen Lu, Lisa Stubbs Jan 1999

Zim1, A Maternally Expressed Mouse Kruppel-Type Zinc-Finger Gene Located In Proximal Chromosome 7, Joomyeong Kim, Xiaochen Lu, Lisa Stubbs

Faculty Publications

In analysis of a conserved region of proximal mouse chromosome 7 and human chromosome 19q, we have isolated a novel mouse gene, Zim1 (imprinted zinc-finger gene 1), encoding a typical Kruppel-type (C2H2) zinc-finger protein, located within 30 kb of a known imprinted gene, Peg3 (paternally expressed gene 3). Our studies demonstrate that Zim1 is also imprinted; the gene is expressed mainly from the maternal allele and at high levels only during embryonic and neonatal stages. In contrast to most tissues, Zim1 is expressed biallelically in neonatal and adult brain with slightly more input from the maternal allele. Zim1 produces multiple …

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Ferric Iron Reduction By Bacteria Associated With The Roots Of Freshwater And Marine Macrophytes, G. M. King, Meredith A. Garey Jan 1999

Ferric Iron Reduction By Bacteria Associated With The Roots Of Freshwater And Marine Macrophytes, G. M. King, Meredith A. Garey

Faculty Publications

In vitro assays of washed, excised roots revealed maximum potential ferric iron reduction rates of >100 μmol g (dry weight)-1 day-1 for three freshwater macrophytes and rates between 15 and 83 μmol (dry weight)-1 day-1 for two marine species. The rates varied with root morphology but not consistently (fine root activity exceeded smooth root activity in some but not all cases). Sodium molybdate added at final concentrations of 0.2 to 20 mM did not inhibit iron reduction by roots of marine macrophytes (Spartina alterniflora and Zostera marina). Roots of a freshwater macrophyte, Sparganium eurycarpum, that were incubated with an analog …

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Complementation Of Conjugation Functions Of Streptomyces Lividans Plasmid Pij101 By The Related Streptomyces Plasmid Psb24.2, Gregg S. Pettis, Shubha Prakash Jan 1999

Complementation Of Conjugation Functions Of Streptomyces Lividans Plasmid Pij101 By The Related Streptomyces Plasmid Psb24.2, Gregg S. Pettis, Shubha Prakash

Faculty Publications

A database search revealed extensive sequence similarity between Streptomyces lividans plasmid pIJ101 and Streptomyces plasmid pSB24.2, which is a deletion derivative of Streptomyces cyanogenus plasmid pSB24.1. The high degree of relatedness between the two plasmids allowed the construction of a genetic map of pSB24.2, consisting of putative transfer and replication loci. Two pSB24.2 loci, namely, the cis-acting locus for transfer (clt) and the transfer-associated korB gene, were shown to be capable of complementing the pIJ101 clt and korB functions, respectively, a result that is consistent with the notion that pIJ101 and the parental plasmid pSB24.1 encode highly similar, if not …

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Rapid Evolution Of Fertilization Selectivity And Lysin Cdna Sequences In Teguline Gastropods, Michael E. Hellberg, Victor D. Vacquier Jan 1999

Rapid Evolution Of Fertilization Selectivity And Lysin Cdna Sequences In Teguline Gastropods, Michael E. Hellberg, Victor D. Vacquier

Faculty Publications

Proteins mediating intercellular recognition face opposing selective forces as they evolve: purifying selection to maintain function, and diversifying selection to alter specificity. Lysin is a 16-kDa protein which enables sperm of free-spawning marine snails to make a hole in the vitelline layer (VE) surrounding conspecific eggs. Previous work on abalone (Haliotis spp.) has shown that positive selection promotes rapid interspecific divergence of lysin. Here, we present data on the specificity of VE dissolution by four species of teguline gastropods, along with lysin cDNA sequences. The teguline and abalone lineages diverged over 250 MYA. As in abalone, VE dissolution by lysin …

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Inhibition Of Plant-Pathogenic Fungi By A Corn Trypsin Inhibitor Overexpressed In Escherichia Coli, Zhi Yuan Chen, Robert L. Brown, Alan R. Lax, Thomas E. Cleveland, John S. Russin Jan 1999

Inhibition Of Plant-Pathogenic Fungi By A Corn Trypsin Inhibitor Overexpressed In Escherichia Coli, Zhi Yuan Chen, Robert L. Brown, Alan R. Lax, Thomas E. Cleveland, John S. Russin

Faculty Publications

The cDNA of a 14-kDa trypsin inhibitor (TI) from corn was subcloned into an Escherichia coli overexpression vector. The overexpressed TI was purified based on its insolubility in urea and then refolded into the active form in vitro. This recombinant TI inhibited both conidium germination and hyphal growth of all nine plant pathogenic fungi studied, including Aspergillus flavus, Aspergillus parasiticus, and Fusarium moniliforme. The calculated 50% inhibitory concentration of TI for conidium germination ranged from 70 to more than 300 μg/ml, and that for fungal growth ranged from 33 to 124 μg/ml depending on the fungal species. It also inhibited …

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Socioeconomic Status And Morbidity In The Last Years Of Life, Youlian Liao, Daniel L. Mcgee, Jay S. Kaufman, Guichan Cao, Richard S. Cooper Jan 1999

Socioeconomic Status And Morbidity In The Last Years Of Life, Youlian Liao, Daniel L. Mcgee, Jay S. Kaufman, Guichan Cao, Richard S. Cooper

Faculty Publications

Objectives. This study evaluated the effect of socioeconomic status, as characterized by level of education, on morbidity and disability in the last years of life. Methods. The analysis used data from the National Health Interview Survey (1986-1990), with mortality follow-up through December 1991. Results. Among 10 932 decedents 50 years or older at baseline interview, educational attainment was inversely associated with long-term limitation of activity, number of chronic conditions, number of bed days, and days of short hospital stay during the year preceding the interview. Conclusions. Decedents with higher socioeconomic status experienced lower morbidity and disability and better quality of …

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Abdominal Adiposity In Six Populations Of West African Descent: Prevalence And Population Attributable Fraction Of Hypertension, Ike S. Okosun, Terrence E. Forrester, Charles N. Rotimi, Babatunde O. Osotimehin, Walinjom F. Muna, Richard S. Cooper Jan 1999

Abdominal Adiposity In Six Populations Of West African Descent: Prevalence And Population Attributable Fraction Of Hypertension, Ike S. Okosun, Terrence E. Forrester, Charles N. Rotimi, Babatunde O. Osotimehin, Walinjom F. Muna, Richard S. Cooper

Faculty Publications

Objectives: The objective of this investigation was to examine the prevalence of abdominal adiposity and its association with the prevalence of hypertension among African descent populations in Nigeria, Cameroon, Jamaica, St. Lucia, Barbados, and the United States (US). Research Method: The data for this investigation were obtained from the International Collaborative Study on Hypertension in Blacks. Hypertension was defined as mean diastolic blood pressure ≥90 mmHg, systolic blood pressure ≥140 mmHg or current treatment with prescribed antihypertension medication. Abdominal overweight was defined as waist circumference (WC) ≥94 and ≥80 cm for men and women, respectively. Abdominal obesity was defined as …

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Maximum-Likelihood Generalized Heritability Estimate For Blood Pressure In Nigerian Families, Charles N. Rotimi, Richard S. Cooper, Guichan Cao, Olufemi Ogunbiyi, Modupe Ladipo, Eme Owoaje, Ryk Ward Jan 1999

Maximum-Likelihood Generalized Heritability Estimate For Blood Pressure In Nigerian Families, Charles N. Rotimi, Richard S. Cooper, Guichan Cao, Olufemi Ogunbiyi, Modupe Ladipo, Eme Owoaje, Ryk Ward

Faculty Publications

Elevated blood pressure (BP) is more common in relatives of hypertensives than in relatives of normotensives, indicating familial resemblance of the BP phenotypes. Most published studies have been conducted in westernized societies. To assess the ability to generalize these estimates, we examined familial patterns of BP in a population-based sample of 510 nuclear families, including 1552 individuals (320 fathers, 370 mothers, 475 sons, and 387 daughters) from Ibadan, Nigeria. The prevalence of obesity in this community is low (body mass index: fathers 21.6; mothers, 23.6; sons, 19.2; and daughters=21.0 kg/m2). The BP phenotype used in all analyses was created from …

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Self-Reported Health Status And Mortality In A Multiethnic Us Cohort, Daniel L. Mcgee, Youlian Liao, Guichan Cao, Richard S. Cooper Jan 1999

Self-Reported Health Status And Mortality In A Multiethnic Us Cohort, Daniel L. Mcgee, Youlian Liao, Guichan Cao, Richard S. Cooper

Faculty Publications

The authors examined the relation between self-reported health status and mortality among the following racial/ethnic groups: Native Americans, Asian/Pacific Islanders, blacks, whites, and Hispanics. They pooled 1986- 1994 data from the National Health Interview Survey to obtain information on more than 700,000 cohort participants. Although fewer than 5,000 Native Americans are included in this cohort, the data provide information previously unavailable for this group. Also included are almost 17,000 Asian/Pacific Islanders, over 90,000 blacks, and over 50,000 Hispanics. The authors found strong associations between self-reported health status and both socioeconomic status and subsequent mortality. A self-report of fair or poor …

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Genetic And Physiologic Analysis Of The Role Of Uncoupling Protein 3 In Human Energy Homeostasis, Wendy K. Chung, Amy Luke, Richard S. Cooper, Charles Rotini, Antonio Vidal-Puig, Michael Rosenbaum, Melvin Chua, Gemma Solanes, Min Zheng, Long Zhao, Charles Leduc, Andrew Eisberg, Florence Chu, Ellen Murphy, Mindy Schreier, Louis Aronne, Sonia Caprio, Bowie Kahle, Derek Gordon, Suzanne M. Leal, Rochelle Goldsmith, Antonio L. Andreu, Claudio Bruno, Salvatore Dimauro, Moonseong Heo, William L. Lowe, Bradford B. Lowell, David B. Allison, Rudolph L. Leibel Jan 1999

Genetic And Physiologic Analysis Of The Role Of Uncoupling Protein 3 In Human Energy Homeostasis, Wendy K. Chung, Amy Luke, Richard S. Cooper, Charles Rotini, Antonio Vidal-Puig, Michael Rosenbaum, Melvin Chua, Gemma Solanes, Min Zheng, Long Zhao, Charles Leduc, Andrew Eisberg, Florence Chu, Ellen Murphy, Mindy Schreier, Louis Aronne, Sonia Caprio, Bowie Kahle, Derek Gordon, Suzanne M. Leal, Rochelle Goldsmith, Antonio L. Andreu, Claudio Bruno, Salvatore Dimauro, Moonseong Heo, William L. Lowe, Bradford B. Lowell, David B. Allison, Rudolph L. Leibel

Faculty Publications

By virtue of its potential effects on rates of energy expenditure, uncoupling protein 3 (UCP3) is an obesity candidate gene. We identified nine sequence variants in UCP3, including Va19Met, Val102Ile, Arg282Cys, and a splice site mutation in the intron between exons 6 and 7. The splice mutation results in an inability to synthesize mRNA for the long isoform (UCP3L) of UCP3. Linkage (sib pair), association, and transmission disequilibrium testing studies on 942 African-Americans did not suggest a significant effect of UCP3 on body composition in this group. In vastus lateralis skeletal muscle of individuals homozygous for the splice mutation, no …

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Statistical Prediction Based On Censored Life Data, Luis A. Escobar, William Q. Meeker Jan 1999

Statistical Prediction Based On Censored Life Data, Luis A. Escobar, William Q. Meeker

Faculty Publications

This article describes methods for using censored life data to construct prediction bounds or intervals for future outcomes. Both new-sample prediction (e.g., using data from a previous sample to make predictions on the future failure time of a new unit) and within-sample prediction problems (e.g., predicting the number of future failures from a sample, based on early data from that sample) are considered. The general method, based on an assumed parametric distribution, uses simulationbased calibration. This method provides exactly the nominal coverage probability when an exact pivotal-based method exists and a highly accurate large-sample approximation, otherwise. To illustrate new-sample prediction, …

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