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Active Immunization Of Japanese Quail Hens With A Recombinant Chicken Inhibin Fusion Protein Enhances Production Performance, J. D. Moreau, D. G. Satterlee, J. J. Rejman, G. G. Cadd, K. G. Kousoulas, W. C. Fioretti Jan 1998

Active Immunization Of Japanese Quail Hens With A Recombinant Chicken Inhibin Fusion Protein Enhances Production Performance, J. D. Moreau, D. G. Satterlee, J. J. Rejman, G. G. Cadd, K. G. Kousoulas, W. C. Fioretti

Faculty Publications

The effects of active immunization against inhibin on production performance in female Japanese quail (Coturnix coturnix japonica) were assessed in two separate trials using an MBP-cINA521 fusion protein as an immunogen. The fusion protein, MBP-cINA521, consisted of the bacterial maltose binding protein (MBP) and a truncated form of the mature α-subunit of chicken inhibin (cINA521). MBP-cINAl521 was constructed by: 1) excising a 521-bp PstI fragment from a chicken inhibin α-subunit cDNA (cINA6; gift of P. A. Johnson), 2) cloning this fragment, which encodes all but the first 11 amino acid residues of the mature α-subunit, into the pMal-c2 vector of …

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Isolation, Culture And Characterization Of A Primary Fibroblast Cell Line From Channel Catfish, Quiyang Zhang, Richard K. Cooper, William R. Wolters, Terrence R. Tiersch Jan 1998

Isolation, Culture And Characterization Of A Primary Fibroblast Cell Line From Channel Catfish, Quiyang Zhang, Richard K. Cooper, William R. Wolters, Terrence R. Tiersch

Faculty Publications

A primary cell line (designated as CCf) derived from caudal fin tissue of channel catfish, Ictalurus punctatus, was developed using explant techniques. The cell line grew fastest in media supplied with FBS and channel catfish serum. The duplication time of the cell line under optimal conditions was ~56 h at a plating density of 1.1 x 105 cells/ml. The cell line has been propagated continuously for 25 passages (1:4 dilution per passage), cryopreserved, and recovered successfully at different passages. The cultured cells had fibroblastic morphology, and synthesized fibronectin and Type I and III collagens in the cytoplasm. The cell line …

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Interactive Effects Of Sodium Bentonite And Coccidiosis With Monensin Or Salinomycin In Chicks, S. J. Gray, T. L. Ward, L. L. Southern, D. R. Ingram Jan 1998

Interactive Effects Of Sodium Bentonite And Coccidiosis With Monensin Or Salinomycin In Chicks, S. J. Gray, T. L. Ward, L. L. Southern, D. R. Ingram

Faculty Publications

Three experiments (Exp.) were conducted to determine the interactive effects of sodium bentonite (NaB) with the efficacy of monensin (MON) or salinomycin (SAL) in coccidiosis-infected chicks. Male broiler chicks 5 to 14 d of age were used, and each treatment was replicated with eight (Exp. 1) or four (Exp. 2 and 3) pens of five chicks each. In Exp. 1, MON (80 ppm), NaB (0.50%), or MON+NaB were fed to uninfected and coccidiosis-infected (5 × 105 sporulated Eimeria acervulina oocysts on Day 2 of the Exp.) chicks in a 2 × 2 × 2 factorial arrangement of treatments. Experiment 2 …

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Performance And Metabolic Responses Of Young Dairy Calves Fed Diets Supplemented With Chromium Tripicolinate, C. L. Depew, L. D. Bunting, J. M. Fernandez, D. L. Thompson, R. W. Adkinson Jan 1998

Performance And Metabolic Responses Of Young Dairy Calves Fed Diets Supplemented With Chromium Tripicolinate, C. L. Depew, L. D. Bunting, J. M. Fernandez, D. L. Thompson, R. W. Adkinson

Faculty Publications

Forty-two Holstein calves were used to study performance and metabolic responses when milk replacer and then postweaning starter were supplemented with 1 ppm of Cr as Cr-tripicolinate. From birth through 8 wk of age, supplemental Cr tended to improve the growth performance of bull calves but not of heifer calves. Starter intake and feed efficiency were not affected by supplemental Cr. From 1 to 5 wk of age, plasma cortisol concentrations sampled just prior to feeding decreased, and concentrations of insulinlike growth factor-I increased. All calves appeared to become less sensitive to insulin as they aged. From 1 to 5 …

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Interactive Effects Of Sodium Bentonite And Coccidiosis With Monensin Or Salinomycin In Chicks, S. J. Gray, T. L. Ward, L. L. Southern, D. R. Ingram Jan 1998

Interactive Effects Of Sodium Bentonite And Coccidiosis With Monensin Or Salinomycin In Chicks, S. J. Gray, T. L. Ward, L. L. Southern, D. R. Ingram

Faculty Publications

Three experiments (Exp.) were conducted to determine the interactive effects of sodium bentonite (NaB) with the efficacy of monensin (MON) or salinomycin (SAL) in coccidiosis-infected chicks. Male broiler chicks 5 to 14 d of age were used, and each treatment was replicated with eight (Exp. 1) or four (Exp. 2 and 3) pens of five chicks each. In Exp. 1, MON (80 ppm), NaB (0.50%), or MON+NaB were fed to uninfected and coccidiosis-infected (5 × 105 sporulated Eimeria acervulina oocysts on Day 2 of the Exp.) chicks in a 2 × 2 × 2 factorial arrangement of treatments. Experiment 2 …

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The Lysine Requirement And Ratio Of Total Sulfur Amino Acids To Lysine For Chicks Fed Adequate Or Inadequate Lysine, T. A. Knowles, L. L. Southern Jan 1998

The Lysine Requirement And Ratio Of Total Sulfur Amino Acids To Lysine For Chicks Fed Adequate Or Inadequate Lysine, T. A. Knowles, L. L. Southern

Faculty Publications

Experiments (Exp.) were conducted with Cornish Rock males (4 to 14 or 15 d of age) to determine the Lys requirement (Exp. 1) and the optimum ratio of TSAA:Lys for chicks fed adequate or inadequate Lys (Exp. 2). In Exp. 1, 180 chicks were allotted on the basis of BW to six treatments with six replications of five chicks each in a completely randomized design (CRD). Average initial and final BW were 73.5 and 415.5 g. The Lys levels fed were: 0.8, 0.9, 1.0, 1.1, 1.2, and 1.3% digestible Lys. In Exp. 2, 240 chicks were allotted on the basis …

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Estimating African American Admixture Proportions By Use Of Population- Specific Alleles, Esteban J. Parra, Amy Marcini, Joshua Akey, Jeremy Martinson, Mark A. Batzer, Richard Cooper, Terrence Forrester, David B. Allison, Ranjan Deka, Robert E. Ferrell, Mark D. Shriver Jan 1998

Estimating African American Admixture Proportions By Use Of Population- Specific Alleles, Esteban J. Parra, Amy Marcini, Joshua Akey, Jeremy Martinson, Mark A. Batzer, Richard Cooper, Terrence Forrester, David B. Allison, Ranjan Deka, Robert E. Ferrell, Mark D. Shriver

Faculty Publications

We analyzed the European genetic contribution to 10 populations of African descent in the United States (Maywood, Illinois; Detroit; New York; Philadelphia; Pittsburgh; Baltimore; Charleston, South Carolina; New Orleans; and Houston) and in Jamaica, using nine autosomal DNA markers. These markers either are population-specific or show frequency differences >45% between the parental populations and are thus especially informative for admixture. European genetic ancestry ranged from 6.8% (Jamaica) to 22.5% (New Orleans). The unique utility of these markers is reflected in the low variance associated with these admixture estimates (SEM 1.3%-2.7%). We also estimated the male and female European contribution to …

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Egg Parasitoids Of Homalodisca Coagulata (Homoptera: Cicadellidae), Serguei V. Triapitsyn, Russell F. Mizell, Janice L. Bossart, Christopher E. Carlton Jan 1998

Egg Parasitoids Of Homalodisca Coagulata (Homoptera: Cicadellidae), Serguei V. Triapitsyn, Russell F. Mizell, Janice L. Bossart, Christopher E. Carlton

Faculty Publications

A survey of egg parasitoids of the leafhopper Homalodisca coagulata was conducted in California, Florida and Louisiana. The mymarid wasp Gonatocerus ashmeadi was found to be the most common natural enemy in all locations sampled; G. fasciatus and the trichogrammatid Zagella sp. are recognized as potential biological control agents for introduction into southern California.

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Identification And Characterization Of A 14-Kilodalton Brucella Abortus Protein Reactive With Antibodies From Naturally And Experimentally Infected Hosts And T Lymphocytes From Experimentally Infected Balb/C Mice, R. L. Chirhart-Gilleland, M. E. Kovach, P. H. Elzer, S. R. Jennings, R. M. Roop Jan 1998

Identification And Characterization Of A 14-Kilodalton Brucella Abortus Protein Reactive With Antibodies From Naturally And Experimentally Infected Hosts And T Lymphocytes From Experimentally Infected Balb/C Mice, R. L. Chirhart-Gilleland, M. E. Kovach, P. H. Elzer, S. R. Jennings, R. M. Roop

Faculty Publications

A low-molecular-weight recombinant Brucella abortus protein reactive with antibodies from a variety of naturally and experimentally infected hosts and T lymphocytes from experimentally infected mice was identified and given the designation BA14K. The gene encoding BA14K was cloned and characterized, and the predicted amino acid sequence of this immunoreactive protein showed no significant homology with previously described proteins. Sequences homologous to the cloned fragment encoding BA14K were identified by Southern blot analysis of genomic DNAs from representatives of all of the currently recognized Brucella species. Studies employing BA14K should contribute to our efforts to better understand the antigenic specificity of …

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The Peak Brightness Of Sn 1974g In Ngc 4414 And The Hubble Constant, Bradley E. Schaefer Jan 1998

The Peak Brightness Of Sn 1974g In Ngc 4414 And The Hubble Constant, Bradley E. Schaefer

Faculty Publications

The light curve of the Type Ia supernova SN 1974G (in NGC 4414) is important because the Hubble Space Telescope has measured the distance to the host galaxy by means of Cepheid variables, and thus the Hubble constant can be derived. Light curves from the secondary literature are inadequate, since the majority of data is misreported, the majority of the published data is overlooked, and the majority of all data is unpublished, while comparison-star sequences have offsets of over half a magnitude. I have recovered and validated all data, remeasured the comparison stars, and performed light-curve template fits. I find …

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Discovery Of A Supernova Explosion At Half The Age Of The Universe, S. Perlmutter, G. Aldering, M. Della Valle, S. Deustua, R. S. Ellis, S. Fabbro, A. Fruchter, G. Goldhaber, D. E. Groom, I. M. Hook, A. G. Kim, M. Y. Kim, R. A. Knop, C. Lidman, R. G. Mcmahon, P. Nugent, R. Pain, N. Panagia, C. R. Pennypacker, P. Ruiz-Lapuente, B. Schaefer, N. Walton Jan 1998

Discovery Of A Supernova Explosion At Half The Age Of The Universe, S. Perlmutter, G. Aldering, M. Della Valle, S. Deustua, R. S. Ellis, S. Fabbro, A. Fruchter, G. Goldhaber, D. E. Groom, I. M. Hook, A. G. Kim, M. Y. Kim, R. A. Knop, C. Lidman, R. G. Mcmahon, P. Nugent, R. Pain, N. Panagia, C. R. Pennypacker, P. Ruiz-Lapuente, B. Schaefer, N. Walton

Faculty Publications

The ultimate fate of the Universe, infinite expansion or a big crunch, can be determined by using the redshifts and distances of very distant supernovae to monitor changes in the expansion rate. We can now find large numbers of these distant supernovae, and measure their redshifts and apparent brightnesses; moreover, recent studies of nearby type Ia supernovae have shown how to determine their intrinsic luminosities- and therefore with their apparent brightnesses obtain their distances. The >50 distant supernovae discovered so far provide a record of changes in the expansion rate over the past several billion years. However, it is necessary …

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Antiferromagnetic Hedgehogs With Superconducting Cores, Paul M. Goldbart, Daniel E. Sheehy Jan 1998

Antiferromagnetic Hedgehogs With Superconducting Cores, Paul M. Goldbart, Daniel E. Sheehy

Faculty Publications

Excitations of the antiferromagnetic state that resemble antiferromagnetic hedgehogs at large distances but are predominantly superconducting inside a core region are discussed within the context of Zhang’s SO(5)-symmetry-based approach to the physics of high-temperature superconducting materials. Nonsingular, in contrast with their hedgehog cousins in pure antiferromagnetism, these texture excitations are what hedgehogs become when the antiferromagnetic order parameter is permitted to “escape” into superconducting directions. The structure of such excitations is determined in a simple setting, and a number of their experimental implications are examined. © 1998 The American Physical Society.

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Intrinsic Resistivity And The So(5) Theory Of High-Temperature Superconductors, Daniel E. Sheehy, Paul M. Goldbart Jan 1998

Intrinsic Resistivity And The So(5) Theory Of High-Temperature Superconductors, Daniel E. Sheehy, Paul M. Goldbart

Faculty Publications

The topological structure of the order parameter in Zhang’s SO(5) theory of superconductivity allows for an unusual type of dissipation mechanism by which current-carrying states can decay. The resistivity due to this mechanism, which involves orientation rather than amplitude order-parameter fluctuations, is calculated for the case of a thin superconducting wire. The approach is a suitably modified version of that pioneered by Langer and Ambegaokar for conventional superconductors. © 1998 The American Physical Society.

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Results On [Formula Presented] Oscillations From Pion Decay In Flight Neutrinos, C. Athanassopoulos, L. B. Auerbach, R. L. Burman, D. O. Caldwell, E. D. Church, I. Cohen, J. B. Donahue, A. Fazely, F. J. Federspiel, G. T. Garvey, R. M. Gunasingha, R. Imlay, K. Johnston, H. J. Kim, W. C. Louis, R. Majkic, K. Mcilhany, W. Metcalf, G. B. Mills, R. A. Reeder, V. Sandberg, D. Smith, I. Stancu, W. Strossman, R. Tayloe, G. J. Vandalen, W. Vernon, N. Wadia, J. Waltz, D. H. White, D. Works, Y. Xiao, S. Yellin Jan 1998

Results On [Formula Presented] Oscillations From Pion Decay In Flight Neutrinos, C. Athanassopoulos, L. B. Auerbach, R. L. Burman, D. O. Caldwell, E. D. Church, I. Cohen, J. B. Donahue, A. Fazely, F. J. Federspiel, G. T. Garvey, R. M. Gunasingha, R. Imlay, K. Johnston, H. J. Kim, W. C. Louis, R. Majkic, K. Mcilhany, W. Metcalf, G. B. Mills, R. A. Reeder, V. Sandberg, D. Smith, I. Stancu, W. Strossman, R. Tayloe, G. J. Vandalen, W. Vernon, N. Wadia, J. Waltz, D. H. White, D. Works, Y. Xiao, S. Yellin

Faculty Publications

A search for [Formula Presented] oscillations has been conducted at the Los Alamos Meson Physics Facility using [Formula Presented] from [Formula Presented] decay in flight. An excess in the number of beam-related events from the [Formula Presented] inclusive reaction is observed. The excess is too large to be explained by normal [Formula Presented] contamination in the beam at a confidence level greater than 99%. If interpreted as an oscillation signal, the observed oscillation probability of [Formula Presented] is consistent with the previously reported [Formula Presented] oscillation evidence from LSND. © 1998 The American Physical Society.

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Egret Observations Of The Extragalactic Gamma-Ray Emission, P. Sreekumar, D. L. Bertsch, B. L. Dingus, J. A. Esposito, C. E. Fichtel, R. C. Hartman, S. D. Hunter, G. Kanbach, D. A. Kniffen, Y. C. Lin, H. A. Mayer-Hasselwander, P. F. Michelson, C. Von Montigny, A. Mücke, R. Mukherjee, P. L. Nolan, M. Pohl, O. Reimer, E. Schneid, J. G. Stacy, F. W. Stecker, D. J. Thompson, T. D. Willis Jan 1998

Egret Observations Of The Extragalactic Gamma-Ray Emission, P. Sreekumar, D. L. Bertsch, B. L. Dingus, J. A. Esposito, C. E. Fichtel, R. C. Hartman, S. D. Hunter, G. Kanbach, D. A. Kniffen, Y. C. Lin, H. A. Mayer-Hasselwander, P. F. Michelson, C. Von Montigny, A. Mücke, R. Mukherjee, P. L. Nolan, M. Pohl, O. Reimer, E. Schneid, J. G. Stacy, F. W. Stecker, D. J. Thompson, T. D. Willis

Faculty Publications

The all-sky survey in high-energy gamma rays (E > 30 MeV) carried out by EGRET aboard the Compton Gamma Ray Observatory provides a unique opportunity to examine in detail the diffuse gamma-ray emission. The observed diffuse emission has a Galactic component arising from cosmic-ray interactions with the local interstellar gas and radiation, as well as an almost uniformly distributed component that is generally believed to originate outside the Galaxy. Through a careful study and removal of the Galactic diffuse emission, the flux, spectrum, and uniformity of the extragalactic emission are deduced. The analysis indicates that the extragalactic emission is well described …

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Simultaneous Observations Of Compton Gamma Ray Observatory-Batse Gamma-Ray Bursts With The Cobe Dmr, Peter D. Jackson, Christoph Winkler, J. Gregory Stacy, T. J.Romke Bontekoe Jan 1998

Simultaneous Observations Of Compton Gamma Ray Observatory-Batse Gamma-Ray Bursts With The Cobe Dmr, Peter D. Jackson, Christoph Winkler, J. Gregory Stacy, T. J.Romke Bontekoe

Faculty Publications

Data acquired with the COBE Differential Microwave Radiometer (DMR) provide a unique opportunity to observe simultaneous emission from cosmic gamma-ray bursts in the previously unexplored microwave region of the spectrum. We have searched the COBE DMR time-ordered data sets for instances when one of the DMR horns (FWHM ∼ 7°) was pointing in the direction of a gamma-ray burst at the time of burst occurrence. During the overlap period 1991 April-December corresponding to the first public release of COBE data, 210 Compton Gamma Ray Observatory (CGRO)/BATSE gamma-ray bursts listed in the Third BATSE (3B) Catalog were viewable by the COBE …

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Quasiclassical Approach To Transport In The Vortex State And The Hall Effect, A. Houghton, I. Vekhter Jan 1998

Quasiclassical Approach To Transport In The Vortex State And The Hall Effect, A. Houghton, I. Vekhter

Faculty Publications

We derive generalized quasiclassical transport equations that include the terms responsible for the Hall effect in the vortex state of a clean type-II superconductor, and calculate the conductivity tensor for an (Formula presented)-wave superconductor in the high-field regime. We find that below the superconducting transition the contribution to the transverse conductivity due to dynamical fluctuations of the order parameter is compensated by the modification of the quasiparticle contribution. In this regime the nonlinear behavior of the Hall angle is governed by the change in the effective quasiparticle scattering rate due to the reduction in the density of states at the …

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Starburst-Like Dust Extinction In The Small Magellanic Cloud, Karl D. Gordon, Geoffrey C. Clayton Jan 1998

Starburst-Like Dust Extinction In The Small Magellanic Cloud, Karl D. Gordon, Geoffrey C. Clayton

Faculty Publications

The recent discovery that the ultraviolet (UV) dust extinction in starburst galaxies is similar to that found in the Small Magellanic Cloud (SMC) motivated us to reinvestigate the UV extinction found in the SMC. We have been able to improve significantly on previous studies by carefully choosing pairs of well-matched reddened and unreddened stars. In addition, we benefited from the improved signal-tonoise ratio of the NEWSIPS International Ultraviolet Explorer (WE) data and the larger sample of SMC stars now available. Searching the WE Final Archive, we found only four suitable early-type stars that were significantly reddened and had well-matched comparison …

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The Spectroscopic Orbit Of The Evolved Binary Hd 197770, Karl D. Gordon, Geoffrey C. Clayton, Tracy L. Smith, Jason P. Aufdenberg, John S. Drilling, Margaret M. Hanson, Christopher M. Anderson, Christopher L. Mulliss Jan 1998

The Spectroscopic Orbit Of The Evolved Binary Hd 197770, Karl D. Gordon, Geoffrey C. Clayton, Tracy L. Smith, Jason P. Aufdenberg, John S. Drilling, Margaret M. Hanson, Christopher M. Anderson, Christopher L. Mulliss

Faculty Publications

We have used spectra taken between 1992 and 1997 to derive the spectroscopic orbit of the eclipsing double-lined spectroscopic binary HD 197770. This binary has a period of 99.69 ± 0.02 days and K amplitudes of 31.2 ± 0.8 and 47.1 ± 0.4 km s-1 for components A and B, respectively. The m sin3 i values for A and B are 2.9 and 1.9, respectively, and are close to the actual masses because of the eclipsing nature of this binary. Both components of HD 197770 have spectral types near B2 III. This means that both components are undermassive by about …

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Macroscopic Studies Of Short-Pulse High-Order Harmonic Generation Using The Time-Dependent Schrödinger Equation, M. B. Gaarde, Ph Antoine, A. L’Huillier, K. J. Schafer, K. C. Kulander Jan 1998

Macroscopic Studies Of Short-Pulse High-Order Harmonic Generation Using The Time-Dependent Schrödinger Equation, M. B. Gaarde, Ph Antoine, A. L’Huillier, K. J. Schafer, K. C. Kulander

Faculty Publications

We consider high harmonic generation by ultrashort (27–108 fs) laser pulses and calculate the macroscopic response of a collection of atoms to such a short pulse. We show how the harmonic spectrum after propagation through the medium is significantly different from the single-atom spectrum. We use single-atom data calculated by integration of the time-dependent Schrödinger equation and propose a method, based on an adiabatic approximation, to extract the data necessary to perform a propagation calculation. © 1998 The American Physical Society.

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Frequency-Resolved Time-Gated High-Order Harmonics, Carlo Altucci, Christian Delfin, Lena Roos, Mette B. Gaarde, Anne L’Huillier, Ian Mercer, Tomas Starczewski, C. G. Wahlström Jan 1998

Frequency-Resolved Time-Gated High-Order Harmonics, Carlo Altucci, Christian Delfin, Lena Roos, Mette B. Gaarde, Anne L’Huillier, Ian Mercer, Tomas Starczewski, C. G. Wahlström

Faculty Publications

We report measurements of high-order harmonic spectra obtained with a 800-nm 150-fs laser pulse with a time-varying degree of ellipticity. The modulation of the polarization in time is achieved by using birefringent optics and self-phase modulation in a glass plate. We can create one or two temporal gates of a few femtoseconds width, during which the polarization is linear and harmonic emission is efficient. The harmonic spectra observed experimentally demonstrate that harmonics generated with linear polarization are frequency chirped. The values measured experimentally are consistent with theoretical predictions based on the strong field approximation. © 1998 The American Physical Society.

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A Balloon-Borne Coded Aperture Telescope For Arc-Minute Angular Resolution At Hard X-Ray Energies, J. Ryan, V. Boykin, R. M. Kippen, K. Larson, J. Macri, M. Mayer, M. Mcconnell, P. Altice, M. L. Cherry, S. B. Ellison, B. Price, T. G. Guzik, R. Lockwood, M. B. Barakat, K. Johnston, N. Zotov, M. Elaasar Jan 1998

A Balloon-Borne Coded Aperture Telescope For Arc-Minute Angular Resolution At Hard X-Ray Energies, J. Ryan, V. Boykin, R. M. Kippen, K. Larson, J. Macri, M. Mayer, M. Mcconnell, P. Altice, M. L. Cherry, S. B. Ellison, B. Price, T. G. Guzik, R. Lockwood, M. B. Barakat, K. Johnston, N. Zotov, M. Elaasar

Faculty Publications

We describe the development of a new balloon-borne telescope known as MARGIE (Minute-of-Arc Resolution Gamma ray Imaging Experiment). It is a coded aperture telescope designed to image photons (in various configurations) over the 20-600 keV range with an angular resolution approaching 1′. MARGIE will use one (or both) of two different detection plane technologies. One such technology involves the use of Cadmium Zinc Telluride (CZT) strip detectors, for which we have successfully demonstrated a spatial resolution of < 375 μm. A second detector option is based on CsI microfiber arrays coupled to a large area silicon CCD readout array, providing spatial resolutions comparable to that of the CZT prototype. In one possible configuration, the coded mask would be 0.5 mm thick tungsten, with 0.5 mm pixels at a distance of 1.5 m from the central detector, giving an angular resolution of 1′ and a fully coded FoV of 12°. © 1998 COSPAR. Published by Elsevier Science Ltd.

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Single-Head Spin Modes In Frontal Polymerization, Victor M. Ilyashenko, John A. Pojman Jan 1998

Single-Head Spin Modes In Frontal Polymerization, Victor M. Ilyashenko, John A. Pojman

Faculty Publications

The single-head spin mode is the first two-dimensional pattern of self-propagating thermal reaction fronts observed after the planar front loses stability. A "hot spot" is observed to propagate around the periphery of the front. The dynamics of the single-head frontal polymerization regime were studied experimentally, and two novel results were found. The "hot spot" was measured and found to be superadiabatic. The relationship between the rotational velocity and the propagating velocity was found. Experimental data were also compared with the theoretical results based on the linear stability analysis and found to be in a reasonable agreement. © 1998 American Institute …

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The Effect Of Convection On A Propagating Front With A Liquid Product: Comparison Of Theory And Experiments, B. Mccaughey, J. A. Pojman, C. Simmons, V. A. Volpert Jan 1998

The Effect Of Convection On A Propagating Front With A Liquid Product: Comparison Of Theory And Experiments, B. Mccaughey, J. A. Pojman, C. Simmons, V. A. Volpert

Faculty Publications

This work is devoted to the investigation of propagating polymerization fronts converting a liquid monomer into a liquid polymer. We consider a simplified mathematical model which consists of the heat equation and equation for the depth of conversion for one-step chemical reaction and of the Navier-Stokes equations under the Boussinesq approximation. We fulfill the linear stability analysis of the stationary propagating front and find conditions of convective and thermal instabilities. We show that convection can occur not only for ascending fronts but also for descending fronts. Though in the latter case the exothermic chemical reaction heats the cold monomer from …

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Hematite And Calcite Coatings On Fossil Vertebrates, B. A.O. Huiming, Paul L. Koch, Robert P. Hepple Jan 1998

Hematite And Calcite Coatings On Fossil Vertebrates, B. A.O. Huiming, Paul L. Koch, Robert P. Hepple

Faculty Publications

Hematite coatings are common on vertebrate fossils from Paleocene/Eocene paleosol deposits in the Bighorn Basin, Wyoming. In general, hematite coatings are found only on fossils and are limited to soils exhibiting hydromorphic features and moderate maturity. Pétrographie and isotopic evidence suggests that hematite and micritic calcite formed at nearly the same time in a pedogenic environment, whereas sparry calcite formed later at greater burial depths. The parent material of paleosols is rich in iron, supplying an ample source of iron for hematite formation. Decomposition of animal tissues around bones may enhance the weathering of iron-bearing minerals in soils surrounding carcasses, …

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Trace And Rare Earth Element Chemistry Of Volcanic Ashes From Sites 918 And 919: Implications For Icelandic Volcanism, P. D. Clift, J. G. Fitton Jan 1998

Trace And Rare Earth Element Chemistry Of Volcanic Ashes From Sites 918 And 919: Implications For Icelandic Volcanism, P. D. Clift, J. G. Fitton

Faculty Publications

Miocene to Holocene sediments cores at Site 918 and 919 in the Irminger Basin contain windblown ash layers drived from Icelandic volcanoes. They represent the most explosive volcanism of the rift system. In contrast, only those eruptions that produced lava flowing far from the rift zone are now exposed on Iceland due to subsidence close to the rift axis. Sediments older than 3.2 Ma contain little fresh glass, due to the hydrating effect of diagenetic fluids, although one basaltic layer dated at 10.5 Ma and three rhyolitic layers data at 12.1-12.7 Ma were found to contain fresh glass. Major, trace, …

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Tectonic Controls On Sedimentation And Diagenesis In The Tonga Trench And Forearc, Southwest Pacific, P. D. Clift, C. J. Macleod, D. R. Tappin, D. J. Wright, S. H. Bloomer Jan 1998

Tectonic Controls On Sedimentation And Diagenesis In The Tonga Trench And Forearc, Southwest Pacific, P. D. Clift, C. J. Macleod, D. R. Tappin, D. J. Wright, S. H. Bloomer

Faculty Publications

Sedimentation in the Tonga forearc is dominated by the redeposition of volcaniclastic sediment from the arc volcanic front by mass flows and turbidity currents onto the adjacent Tonga Platform, the shallowest, flattest part of the forearc region. The greatest sediment thicknesses accumulate in debris aprons close to the volcanic front. Collision of seamounts, notably the Capricorn Seamount and the Louisville Ridge, with the forearc radically shortens and steepens the adjacent modern trench slope, allowing sediment to be redeposited deep into the trench. Rotation, usually arcward, of existing basins on the midslope during collision generates angular unconformities, while synchronous uplift of …

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Antarctic Paleolake Sediments And The Search For Extinct Life On Mars, Peter T. Doran, Robert A. Wharton, David J. Des Marais, Christopher P. Mckay Jan 1998

Antarctic Paleolake Sediments And The Search For Extinct Life On Mars, Peter T. Doran, Robert A. Wharton, David J. Des Marais, Christopher P. Mckay

Faculty Publications

Evidence of lakes in Mars history is substantial. The proposed similarities between the ancient Martian environment and certain modem environments on Earth have led exobiologists to study antarctic lakes as analogs to those purported to have existed on Mars. We have investigated modem sedimentation processes (especially with respect to δ13C of carbonate and organic matter) in lakes in the McMurdo Dry Valleys region of east Antarctica and assessed various paleolakc deposits with respect to their utility as Martian analogs and targets for future Mars exobiology missions. Three main types of paleolake deposit were identified and assessed: strand lines, perched deltas, …

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Monophyletic Subgroups Of The Tribe Millettieae (Leguminosae) As Revealed By Phytochrome Nucleotide Sequence Data, Matt Lavin, Elisa Eshbaugh, Jer Ming Hu, Sarah Mathews, Robert A. Sharrock Jan 1998

Monophyletic Subgroups Of The Tribe Millettieae (Leguminosae) As Revealed By Phytochrome Nucleotide Sequence Data, Matt Lavin, Elisa Eshbaugh, Jer Ming Hu, Sarah Mathews, Robert A. Sharrock

Faculty Publications

Phylogenetic analysis of phytochrome (PHY) genes reveals the identity and relationships of four PHY loci among papilionoid Leguminosae. A phylogenetic analysis of loci combined according to species suggests that most of the tribe Millettieae belongs to one of two monophyletic clades: the Derris-Lonchocarpus or the Tephrosia clade. Together these two form a monophyletic group that is sister to a lineage represented by Millettia grandis of Millettia sect. Compresso-gemmatae. Collectively, this large monophyletic group is referred to as the Millettieae-core group, which based on our sampling, includes species of Millettieae that do not accumulate the nonprotein amino acid canavanine and that …

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Molecular Cloning And Hormonal Regulation Of A Murine Epididymal Retinoic Acid-Binding Protein Messenger Ribonucleic Acid, Jean Jacques Lareyre, Weng Li Zheng, Guang Quan Zhao, Susan Kasper, Marcia E. Newcomer, Robert J. Matusik, David E. Ong, Marie Claire Orgebin-Crist Jan 1998

Molecular Cloning And Hormonal Regulation Of A Murine Epididymal Retinoic Acid-Binding Protein Messenger Ribonucleic Acid, Jean Jacques Lareyre, Weng Li Zheng, Guang Quan Zhao, Susan Kasper, Marcia E. Newcomer, Robert J. Matusik, David E. Ong, Marie Claire Orgebin-Crist

Faculty Publications

A complementary DNA encoding the mouse epididymal secretory protein MEP 10 (mouse epididymal protein 10) was cloned and is now renamed murine epididymal retinoic acid binding protein (mE-RABP). The analysis of the predicted primary amino acid sequence showed that mE-RABP has a 75% identity with rat ESP I (epididymal secretory protein I), another epididymal retinoic acid-binding protein. The homology strongly suggests that mE-RABP is the mouse orthologue of rat ESP I. A computer analysis of the predicted three- dimensional structure confirmed that mE-RABP can accommodate retinoic acid as ligand. In the rat, ESP I messenger RNA (mRNA) is expressed in …

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