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Gastrointestinal Motility And Disease In Large Animals, Christine B. Navarre, Allen J. Roussel Jan 1996

Gastrointestinal Motility And Disease In Large Animals, Christine B. Navarre, Allen J. Roussel

Faculty Publications

An understanding of the relationship between gastrointestinal (GI) motility and disease is imperative for the proper treatment of large animal patients, especially as new therapeutic agents become available. However, the abundance of information that has become available in the last 2 decades makes gaining this understanding a formidable task. This article summarizes the changes in GI motility caused by some common diseases and conditions encountered in large animal practice, such as GI obstruction, postoperative ileus, resection and anastomosis, diarrhea, endotoxemia, GI parasitism, hypocalcemia, and pregnancy. Copyright © 1996 by the American College of Veterinary Internal Medicine.

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Gastrointestinal Motility And Disease In Large Animals, Christine B. Navarre, Allen J. Roussel Jan 1996

Gastrointestinal Motility And Disease In Large Animals, Christine B. Navarre, Allen J. Roussel

Faculty Publications

An understanding of the relationship between gastrointestinal (GI) motility and disease is imperative for the proper treatment of large animal patients, especially as new therapeutic agents become available. However, the abundance of information that has become available in the last 2 decades makes gaining this understanding a formidable task. This article summarizes the changes in GI motility caused by some common diseases and conditions encountered in large animal practice, such as GI obstruction, postoperative ileus, resection and anastomosis, diarrhea, endotoxemia, GI parasitism, hypocalcemia, and pregnancy. Copyright © 1996 by the American College of Veterinary Internal Medicine.

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The Mobile Genetic Element Alu In The Human Genome, Gabriel E. Novick, Mark A. Batzer, Prescott L. Deininger, Rene J. Herrera Jan 1996

The Mobile Genetic Element Alu In The Human Genome, Gabriel E. Novick, Mark A. Batzer, Prescott L. Deininger, Rene J. Herrera

Faculty Publications

No abstract provided.

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Alu Fossil Relics - Distribution And Insertion Polymorphism, Santosh S. Arcot, Aaron W. Adamson, Jane E. Lamerdin, Brian Kanagy, Prescott L. Deininger, Anthony V. Carrano, Mark A. Batzer Jan 1996

Alu Fossil Relics - Distribution And Insertion Polymorphism, Santosh S. Arcot, Aaron W. Adamson, Jane E. Lamerdin, Brian Kanagy, Prescott L. Deininger, Anthony V. Carrano, Mark A. Batzer

Faculty Publications

Screening of a human genomic library with an oligonucleotide probe specific for one of the young subfamilies of Alu repeats (Ya5/8) resulted in the identification of several hundred positive clones. Thirty-three of these clones were analyzed in detail by DNA sequencing. Oligonucleotide primers complementary to the unique sequence regions flanking each Alu repeat were used in PCR-based assays to perform phylogenetic analyses, chromosomal localization, and insertion polymorphism analyses within different human population groups. All 33 Alu repeats were present only in humans and absent from orthologous positions in several nonhuman primate genomes. Seven Alu repeats were polymorphic for their presence/absence …

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Development Of A Defined Minimal Medium For The Growth Of Edwardsiella Ictaluri, L. A. Collins, R. L. Thune Jan 1996

Development Of A Defined Minimal Medium For The Growth Of Edwardsiella Ictaluri, L. A. Collins, R. L. Thune

Faculty Publications

In this report, a complete defined medium and a minimally defined medium are described for Edwardsiella ictaluri. The complete defined medium consists of 46 individual components, including a basal salt solution, glucose, magnesium sulfate, iron sulfate, six trace metals, four nucleotides, 10 vitamins, and 19 amino acids. This medium supports growth in broth and on solid media. Optimal growth at 30°C was obtained at pH 7.0, and at an osmolality of 390 mosmol/kg of H2O, with a glucose concentration of 4 g/liter. The defined minimal medium reduces the 46 components of the complete medium to eight essential components, including the …

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Historical Diversification Of Birds In Northwestern South America: A Molecular Perspective On The Role Of Vicariant Events, Robb T. Brumfield, A. P. Capparella Jan 1996

Historical Diversification Of Birds In Northwestern South America: A Molecular Perspective On The Role Of Vicariant Events, Robb T. Brumfield, A. P. Capparella

Faculty Publications

Studies of South American biodiversity have identified several areas of endemism that may have enhanced historical diversification of South American organisms. Hypotheses concerning the derivation of birds in the Choco area of endemism in northwestern South America were evaluated using protein electrophoretic data from 14 taxonomically diverse species groups of birds. Nine of these groups demonstrated that the Choco area of endemism has a closer historical relationship to Central America than to Amazonia, a result that is consistent with phytogeographic evidence. Within species groups, genetic distances between cis-Andean (east of the Andes) and trans-Andean (west of the Andes) taxa are, …

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High-Multiplicity Lead-Lead Interactions At 158 Gev/C Per Nucleon, P. Deines-Jones, M. L. Cherry, A. Dabrowska, R. Holynski, W. V. Jones, E. D. Kolganova, D. Kudzia, B. S. Nilsen, A. Olszewski, E. A. Pozharova, K. Sengupta, M. Szarska, A. Trzupek, C. J. Waddington, J. P. Wefel, B. Wilczynska, H. Wilczynski, W. Wolter, B. Wosiek, K. Wozniak Jan 1996

High-Multiplicity Lead-Lead Interactions At 158 Gev/C Per Nucleon, P. Deines-Jones, M. L. Cherry, A. Dabrowska, R. Holynski, W. V. Jones, E. D. Kolganova, D. Kudzia, B. S. Nilsen, A. Olszewski, E. A. Pozharova, K. Sengupta, M. Szarska, A. Trzupek, C. J. Waddington, J. P. Wefel, B. Wilczynska, H. Wilczynski, W. Wolter, B. Wosiek, K. Wozniak

Faculty Publications

The Krakow-Louisiana-Minnesota-Moscow Collaboration (KLMM) has exposed a set of emulsion chambers with lead targets to a 158 GeV/c per nucleon beam of 208Pb nuclei, and we report the initial analysis of 40 high-multiplicity Pb-Pb collisions. To test the validity of the superposition model of nucleus-nucleus interactions in this new regime, we compare the shapes of the pseudorapidity distributions with FRITIOF Monte Carlo model calculations, and find close agreement for even the most central events. We characterize head-on collisions as having a mean multiplicity of 1550± 120 and a peak pseudorapidity density of 390± 30. These estimates are significantly lower than …

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Ultrasound Attenuation In Gap-Anisotropic Systems, J. Moreno, P. Coleman Jan 1996

Ultrasound Attenuation In Gap-Anisotropic Systems, J. Moreno, P. Coleman

Faculty Publications

Transverse ultrasound attenuation provides a weakly coupled probe of momentum current correlations in electronic systems. We develop a simple theory for the interpretation of transverse ultrasound attenuation coefficients in systems with nodal gap anisotropy. Applying this theory we show how ultrasound can delineate between extended-(Formula presented) and (Formula presented)-wave scenarios for the cuprate superconductors. © 1996 The American Physical Society.

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The Peak Brightness Of Sn 1960f In Ngc 4496 And The Hubble Constant, Bradley E. Schaefer Jan 1996

The Peak Brightness Of Sn 1960f In Ngc 4496 And The Hubble Constant, Bradley E. Schaefer

Faculty Publications

The light curve of the Type Ia supernova SN1960F (in NGC 4496) is important because the Bubble Space Telescope has measured the distance to the host galaxy by means of Cepheid variables, and thus the Hubble constant can be derived. Important parameters in this derivation include the peak magnitude as well as the decline rate of the supernova. In this Letter, I report on the results of my quantitative light-curve template fitting to all published data. These reported data are widely discrepant yet can be made all consistent after the brightnesses of the comparison stars are brought onto the Johnson …

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Measurement Of Elastic Ω Photoproduction At Hera, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. R. Okrasiński, J. Repond, R. Stanek, R. L. Talaga, H. Zhang, M. C.K. Mattingly, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, P. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam Jan 1996

Measurement Of Elastic Ω Photoproduction At Hera, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. R. Okrasiński, J. Repond, R. Stanek, R. L. Talaga, H. Zhang, M. C.K. Mattingly, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, P. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam

Faculty Publications

No abstract provided.

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Evidence For Ν¯Μ → Ν¯E Oscillations From The Lsnd Experiment At The Los Alamos Meson Physics Facility, C. Athanassopoulos, L. B. Auerbach, R. L. Burman, I. Cohen, D. O. Caldwell, B. D. Dieterle, J. B. Donahue, A. M. Eisner, A. Fazely, F. J. Federspiel, G. T. Garvey, M. Gray, R. M. Gunasingha, R. Imlay, K. Johnston, H. J. Kim, W. C. Louis, R. Majkic, J. Margulies, 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, Y. X. Wang Jan 1996

Evidence For Ν¯Μ → Ν¯E Oscillations From The Lsnd Experiment At The Los Alamos Meson Physics Facility, C. Athanassopoulos, L. B. Auerbach, R. L. Burman, I. Cohen, D. O. Caldwell, B. D. Dieterle, J. B. Donahue, A. M. Eisner, A. Fazely, F. J. Federspiel, G. T. Garvey, M. Gray, R. M. Gunasingha, R. Imlay, K. Johnston, H. J. Kim, W. C. Louis, R. Majkic, J. Margulies, 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, Y. X. Wang

Faculty Publications

A search for ν¯μ → ν¯e oscillations has been conducted at the Los Alamos Meson Physics Facility by using ν¯μ from μ+ decay at rest. The ν¯e are detected via the reaction ν¯e p → e+ n, correlated with a γ from np → dγ (2.2 MeV). The use of tight cuts to identify e+ events with correlated γ rays yields 22 events with e+ energy between 36 and 60 MeV and only 4.6 ± 0.6 background events. A fit to the e+ events between 20 and 60 MeV yields a total excess of 51.8+18.7−16.9 ± 8.0 events. If attributed …

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Evidence For Neutrino Oscillations From Muon Decay At Rest, C. Athanassopoulos, L. B. Auerbach, R. L. Burman, I. Cohen, D. O. Caldwell, B. D. Dieterle, J. B. Donahue, A. M. Eisner, A. Fazely, F. J. Federspiel, G. T. Garvey, M. Gray, R. M. Gunasingha, R. Imlay, K. Johnston, H. J. Kim, W. C. Louis, R. Majkic, J. Margulies, 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, Y. X. Wang Jan 1996

Evidence For Neutrino Oscillations From Muon Decay At Rest, C. Athanassopoulos, L. B. Auerbach, R. L. Burman, I. Cohen, D. O. Caldwell, B. D. Dieterle, J. B. Donahue, A. M. Eisner, A. Fazely, F. J. Federspiel, G. T. Garvey, M. Gray, R. M. Gunasingha, R. Imlay, K. Johnston, H. J. Kim, W. C. Louis, R. Majkic, J. Margulies, 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, Y. X. Wang

Faculty Publications

A search for ν̄μ→ν̄e oscillations has been conducted at the Los Alamos Meson Physics Facility using ν̄μ from μ+ decay at rest. The ν̄e are detected via the reaction ν̄ep→e+n, correlated with the 2.2 MeV γ from np→dγ. The use of tight cuts to identify e+ events with correlated γ rays yields 22 events with e+ energy between 36 and 60 MeV and only 4.6±0.6 background events. The probability that this excess is due entirely to a statistical fluctuation is 4.1×10-8. A χ2 fit to the entire e+ sample results in a total excess of 51.0+20.2-19.5±8.0 events with e+ energy …

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Inclusive Charged Particle Distributions In Deep Inelastic Scattering Events At Hera, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. Repond, R. Stanek, R. L. Talaga, H. Zhang, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, P. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari, A. Polini, G. Sartorelli Jan 1996

Inclusive Charged Particle Distributions In Deep Inelastic Scattering Events At Hera, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. Repond, R. Stanek, R. L. Talaga, H. Zhang, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, P. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari, A. Polini, G. Sartorelli

Faculty Publications

A measurement of inclusive charged particle distributions in deep inelastic ep scattering for γ*p centre-of-mass energies 75 < W < 175 GeV and momentum transfer squared 10 < Q2 < 160 GeV2 from the ZEUS detector at HERA is presented. The differential charged particle rates in the γ*p centre-of-mass system as a function of the scaled longitudinal momentum, xF, and of the transverse momentum, pt* and , as a function of xF, W and Q2 are given. Separate distributions are shown for events with (LRG) and without (NRG) a rapidity gap with respect to the proton direction. The data are compared with results from experiments at lower beam energies, with the naive quark parton model and with parton models including perturbative QCD corrections. The comparison shows the importance of the higher order QCD processes. Significant differences of the inclusive charged particle rates between NRG and LRG events at the same W are observed. The value of for LRG events with a hadronic mass MX, which excludes the forward produced baryonic system, is similar to the

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Measurement Of The Diffractive Cross Section In Deep Inelastic Scattering, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. R. Okrasinski, J. Repond, R. Stanek, R. L. Talaga, H. Zhang, M. C.K. Mattingly, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, P. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari Jan 1996

Measurement Of The Diffractive Cross Section In Deep Inelastic Scattering, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. R. Okrasinski, J. Repond, R. Stanek, R. L. Talaga, H. Zhang, M. C.K. Mattingly, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, P. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari

Faculty Publications

Diffractive scattering of γ∗p → X + N, where N is either a proton or a nucleonic system with MN < 4 GeV has been measured in deep inelastic scattering (DIS) at HERA. The cross section was determined by a novel method as a function of the γ∗p c.m. energy W between 60 and 245 GeV and of the mass MX of the system X up to 15 GeV at average Q2 values of 14 and 31 GeV2. The diffractive cross section dσdi f f /dMX is, within errors, found to rise linearly with W. Parameterizing the W dependence by the form dσdi f f /dMX ∞ (W2)(2αIP - 2) the DIS data yield for the pomeron trajectory αIP = 1.23±0.02(stat)±0.04(syst) averaged over t in the measured kinematic range assuming the longitudinal photon contribution to be zero. This value for the pomeron trajectory is substantially larger than αIP extracted from soft interactions. The value of αIP measured in this analysis suggests that a substantial part of the diffractive DIS cross section originates from processes which can be described by perturbative QCD. From the measured diffractive cross sections the diffractive structure function of the proton F2D(3) (β,Q2, xIP) has been determined, where β is the momentum fraction of the struck quark in the pomeron. The form F2D(3) = constant·(1/xIP)a gives a good fit to the data in all β and Q2 intervals with a = 1.46 ± 0.04(stat) ± 0.08(syst).

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Measurement Of The F2 Structure Function In Deep Inelastic E+P Scattering Using 1994 Data From The Zeus Detector At Hera, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. R. Okrasinski, J. Repond, R. Stanek, R. L. Talaga, H. Zhang, M. C.K. Mattingly, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, P. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam Jan 1996

Measurement Of The F2 Structure Function In Deep Inelastic E+P Scattering Using 1994 Data From The Zeus Detector At Hera, M. Derrick, D. Krakauer, S. Magill, D. Mikunas, B. Musgrave, J. R. Okrasinski, J. Repond, R. Stanek, R. L. Talaga, H. Zhang, M. C.K. Mattingly, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, P. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam

Faculty Publications

We present measurements of the structure function F2 in e+p scattering at HERA in the range 3.5 GeV2 < Q2 < 5000 GeV2. A new reconstruction method has allowed a significant improvement in the resolution of the kinematic variables and an extension of the kinematic region covered by the experiment. At Q2 < 35 GeV2 the range in x now spans 6.3 · 10-5 < x < 0.08 providing overlap with measurements from fixed target experiments. At values of Q2 above 1000 GeV2 the x range extends to 0.5. Systematic errors below 5% have been achieved for most of the kinematic region. The structure function rises as x decreases; the rise becomes more pronounced as Q2 increases. The behaviour of the structure function data is well described by next-to-leading order perturbative QCD as implemented in the DGLAP evolution equations. © Springer-Verlag 1996.

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The Allegro Gravitational Wave Detector: Data Acquisition And Analysis, E. Mauceli, Z. K. Geng, W. O. Hamilton, W. W. Johnson, S. Merkowitz, A. Morse, B. Price, N. Solomonson Jan 1996

The Allegro Gravitational Wave Detector: Data Acquisition And Analysis, E. Mauceli, Z. K. Geng, W. O. Hamilton, W. W. Johnson, S. Merkowitz, A. Morse, B. Price, N. Solomonson

Faculty Publications

We discuss the data acquisition and analysis procedures used on the Allegro gravity wave detector, including a full description of the filtering used for bursts of gravity waves. The uncertainties introduced into timing and signal strength estimates due to stationary noise are measured, giving the windows for both quantities in coincidence searches. © 1996 The American Physical Society.

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Growing Trees In A Greener World: Industrial Forestry In The 21st Century: 35th Lsu Forestry Symposium, 1996, School Of Forestry, Louisiana State University, Baton Rouge, Louisiana, Usa, Mason C. Carter Jan 1996

Growing Trees In A Greener World: Industrial Forestry In The 21st Century: 35th Lsu Forestry Symposium, 1996, School Of Forestry, Louisiana State University, Baton Rouge, Louisiana, Usa, Mason C. Carter

Proceedings [of the] Annual Forestry Symposium

No abstract provided.

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Preliminary Results From The Russian-American Gallium Experiment Cr-Neutrino Source Measurement, S. R. Elliott, J. N. Abdurashitov, T. J. Bowles, M. L. Cherry, B. T. Cleveland, T. Daily, R. Davis, V. N. Gavrin, S. V. Girin, V. V. Gorbatschev, A. O. Gusev, A. V. Kalikhov, N. G. Khairnasov, V. N. Karaulov, T. V. Knodel, V. N. Kornoukhov, Yu S. Khomyakov, K. Lande, C. K. Lee, V. L. Levitin, V. I. Maev, I. N. Mirmov, P. I. Nazarenko, J. S. Nico, A. M. Pshukov, A. M. Shalagin, A. A. Shikhin, V. S. Shkol'nik, N. V. Skorikov, W. A. Teasdale, E. P. Veretenkin, V. M. Vermul, D. L. Wark Jan 1996

Preliminary Results From The Russian-American Gallium Experiment Cr-Neutrino Source Measurement, S. R. Elliott, J. N. Abdurashitov, T. J. Bowles, M. L. Cherry, B. T. Cleveland, T. Daily, R. Davis, V. N. Gavrin, S. V. Girin, V. V. Gorbatschev, A. O. Gusev, A. V. Kalikhov, N. G. Khairnasov, V. N. Karaulov, T. V. Knodel, V. N. Kornoukhov, Yu S. Khomyakov, K. Lande, C. K. Lee, V. L. Levitin, V. I. Maev, I. N. Mirmov, P. I. Nazarenko, J. S. Nico, A. M. Pshukov, A. M. Shalagin, A. A. Shikhin, V. S. Shkol'nik, N. V. Skorikov, W. A. Teasdale, E. P. Veretenkin, V. M. Vermul, D. L. Wark

Faculty Publications

The Russian-American Gallium Experiment has been collecting solar neutrino data since early 1990. The flux measurement of solar neutrinos is well below that expected from solar models. We discuss the initial results of a measurement of experimental efficiencies by exposing the gallium target to neutrinos from an artificial source. The capture rate of neutrinos from this source is very close to that which is expected. The result can be expressed as a ratio of the measured capture rate to the anticipated rate from the source activity. This ratio is 0.93 + 0.15, - 0.17 where the systematic and statistical errors …

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The Macho Project Large Magellanic Cloud Variable Star Inventory. Iv. New R Coronae Borealis Stars, C. Alcock, R. A. Allsman, D. R. Alves, T. S. Axelrod, A. Decker, D. P. Bennett, G. C. Clayton, K. H. Cook, K. C. Freeman, K. Griest, J. A. Guern, D. Kilkenny, M. J. Lehner, S. L. Marshall, D. Minniti, B. A. Peterson, M. R. Pratt, P. J. Quinn, A. W. Rodgers, C. W. Stubbs, W. Sutherland, D. Welch Jan 1996

The Macho Project Large Magellanic Cloud Variable Star Inventory. Iv. New R Coronae Borealis Stars, C. Alcock, R. A. Allsman, D. R. Alves, T. S. Axelrod, A. Decker, D. P. Bennett, G. C. Clayton, K. H. Cook, K. C. Freeman, K. Griest, J. A. Guern, D. Kilkenny, M. J. Lehner, S. L. Marshall, D. Minniti, B. A. Peterson, M. R. Pratt, P. J. Quinn, A. W. Rodgers, C. W. Stubbs, W. Sutherland, D. Welch

Faculty Publications

We report the discovery of two new R Coronae Borealis (RGB) stars in the LMC using the MACHO project photometry database. The identification of both stars has been confirmed spectroscopically. One is a cool RGB star (Teff ∼ 5000 K), characterized by very strong Swan bands of C2 and violet bands of CN, and weak or absent Bahner lines, G band, and 12C13C bands. The second star is an example of a hot RGB star, of which only three were previously known to exist in the Galaxy and none in the LMC. Its spectrum is characterized by several G n …

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Lattice Dynamics Of Ii-Vi Materials Using The Adiabatic Bond-Charge Model, B. Rajput, D. Browne Jan 1996

Lattice Dynamics Of Ii-Vi Materials Using The Adiabatic Bond-Charge Model, B. Rajput, D. Browne

Faculty Publications

We extend the adiabatic bond-charge model, originally developed for group IV semiconductors and III-V compounds, to study phonons in more ionic II-VI compounds with a zinc-blende structure. Phonon spectra, density of states, and specific heats are calculated for six II-VI compounds and compared with both experimental data and the results of other models. We show that the six-parameter bond-charge model gives a good description of the lattice dynamics of these materials. We also discuss trends in the parameters with respect to the ionicity and metallicity of these compounds. © 1996 The American Physical Society.

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First-Principles Lcgo Calculation Of The Magneto-Optical Properties Of Nickel And Iron, Neeraj Mainkar, D. Browne, J. Callaway Jan 1996

First-Principles Lcgo Calculation Of The Magneto-Optical Properties Of Nickel And Iron, Neeraj Mainkar, D. Browne, J. Callaway

Faculty Publications

We report a first-principles, self-consistent, all-electron, linear combination of Gaussian orbitals calculation of a comprehensive collection of magneto-optical properties of nickel and iron based on density-functional theory. Among the many magneto-optical effects, we have studied the equatorial Kerr effect for absorption in the optical as well as soft-x-ray region, where it is called x-ray magnetic linear dichroism. In the optical region the effect is of the order of 2% while in the x-ray region it is of the order of 1% for the incident angles considered. In addition, the polar Kerr effect, x-ray magnetic circular dichroism, and total x-ray absorption …

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The Russian-American Gallium Experiment (Sage) Cr Neutrino Source Measurement, 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, 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, P. W. Wildenhain, Y. U.S. Khomyakov Jan 1996

The Russian-American Gallium Experiment (Sage) Cr Neutrino Source Measurement, 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, 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, P. W. Wildenhain, Y. U.S. Khomyakov

Faculty Publications

The solar neutrino capture rate measured by SAGE is well below that predicted by solar models. To check the overall experimental efficiency, we exposed 13 tonnes of Ga metal to a reactor-produced 517 kCi source of 51Cr. The ratio of the measured production rate to that predicted from the source activity is 0.95+/-0.11\(stat\)+0.05/-0.08\(syst\). This agreement verifies that the experimental efficiency is measured correctly, establishes that there are no unknown systematic errors at the 10% level, and provides considerable evidence for the reliability of the solar neutrino measurement. © 1996 The American Physical Society.

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Isotopic Evolution Of The Tonga Arc During Lau Basin Rifting; Evidence From The Volcaniclastic Record, Peter D. Clift, Pieter Z. Vroon Jan 1996

Isotopic Evolution Of The Tonga Arc During Lau Basin Rifting; Evidence From The Volcaniclastic Record, Peter D. Clift, Pieter Z. Vroon

Faculty Publications

New Pb, Sr and Nd isotope data from volcaniclastic sediments recovered from the Tonga forearc and Lau Basin permit the isotopic evolution of a section of this arc system, next to the modern island of Ata, to be traced through the backarc basin rifting process from 7·0 Ma to the present. The new data suggest that the isotopic character of the mantle wedge remains constant, and of Pacific mid-ocean ridge basalt (MORB) character, during the early rifting phase. The isotopic evidence supports trace element data in showing an increase in the sediment contribution to arc petrogenesis about 2-3 m.y. after …

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Pervanadate Activation Of Intracellular Kinases Leads To Tyrosine Phosphorylation And Shedding Of Syndecan-1, Jane Reiland, Vanessa L. Ott, Connie S. Lebakken, Charles Yeaman, James Mccarthy, Alan C. Rapraeger Jan 1996

Pervanadate Activation Of Intracellular Kinases Leads To Tyrosine Phosphorylation And Shedding Of Syndecan-1, Jane Reiland, Vanessa L. Ott, Connie S. Lebakken, Charles Yeaman, James Mccarthy, Alan C. Rapraeger

Faculty Publications

Syndecan-1 is a transmembrane haparan sulphate proteoglycan that binds extracellular matrices and growth factors, making it a candidate to act between these regulatory molecules and intracellular signalling pathways. It has a highly conserved transmembrane/cytoplasmic domain that contains four conserved tyrosines. One of these is in a consensus sequence for tyrosine kinase phosphorylation. As an initial step to investigating whether or not phosphorylation of these tyrosines is part of a signal-transduction pathway, we have monitored the tyrosine phosphorylation of syndecan-1 by cytoplasmic tyrosine kinases in intact cells. Tyrosine phosphorylation of syndecan-1 is observed when NMuMG cells are treated with sodium orthovanadate …

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A Low-Co2-Inducible Gene Encoding An Alanine:Α-Ketoglutarate Aminotransferase In Chlamydomonas Reinhardtii, Zhi Yuan Chen, Mark D. Burow, Catherine B. Mason, James V. Moroney Jan 1996

A Low-Co2-Inducible Gene Encoding An Alanine:Α-Ketoglutarate Aminotransferase In Chlamydomonas Reinhardtii, Zhi Yuan Chen, Mark D. Burow, Catherine B. Mason, James V. Moroney

Faculty Publications

At low-CO2 (air) conditions, the unicellular green alga Chlamydomonas reinhardtii acquires the ability to raise its internal inorganic carbon concentration. To study this adaptation to low CO2, cDNA clones induced under low-CO2 growth conditions were selected through differential screening. One full-length clone is 2552 bp, with an open reading frame encoding 521 amino acids. The deduced amino acid sequence shows about 50% identity with alanine:α-ketoglutarate aminotransferase (Ala AT, EC 2.6.1.2) from plants and animals, and the mRNA of this clone increased 4- to 5-fold 4 h after cells were switched from high-CO2 to low-CO2 growth conditions. The expression of the …

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Metabolism Of Gemmules From The Freshwater Sponge Eunapius Fragilis During Diapause And Post-Diapause States, Stephen H. Loomis, Steven C. Hand, Paul E. Fell Jan 1996

Metabolism Of Gemmules From The Freshwater Sponge Eunapius Fragilis During Diapause And Post-Diapause States, Stephen H. Loomis, Steven C. Hand, Paul E. Fell

Faculty Publications

Post-diapause gemmules of the freshwater sponge Eunapius fragilis remained quiescent when maintained at 5°C. Germination occurred within 48 to 72 h following warming to 20°-23°C, culminating with the emergence of a new sponge from the collagenous capsule. Both heat dissipation and oxygen consumption climbed steadily during germination and eventually reached 600% of the starting values. By comparison, energy flow was much lower over the same period of time in diapausing gemmules, clearly demonstrating metabolic depression during diapause. The calorimetric:respirometric (CR) ratio increased significantly from -354 kJ/mol O2 to -541 kJ/mol O2 between hours 3.5 and 56.5 of germination, with an …

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Effect Of Mutations On The Sensitivity Of Human Beta-Cell Glucokinase To Liver Regulatory Protein, M. Veiga-Da-Cunha, L. Z. Xu, Y. H. Lee, D. Marotta, S. J. Pilkis, E. Van Schaftingen Jan 1996

Effect Of Mutations On The Sensitivity Of Human Beta-Cell Glucokinase To Liver Regulatory Protein, M. Veiga-Da-Cunha, L. Z. Xu, Y. H. Lee, D. Marotta, S. J. Pilkis, E. Van Schaftingen

Faculty Publications

Human beta-cell glucokinase and its liver counterpart displayed a half-saturating concentration of glucose (S0.5) of about 8 mmol/l and a Hill coefficient of 1.7, and were as sensitive to inhibition by the rat liver regulatory protein as the rat liver enzyme. These results indicate that the N-terminal region of glucokinase, which differs among these three enzymes, is not implicated in the recognition of the regulatory protein. They also suggest that the regulatory protein, or a related protein, could modulate the affinity of glucokinase for glucose in beta cells. We have also tested the effect of several mutations, many of which …

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Responses Of Methanotrophic Activity In Soils And Cultures To Water Stress, S. Schnell, G. M. King Jan 1996

Responses Of Methanotrophic Activity In Soils And Cultures To Water Stress, S. Schnell, G. M. King

Faculty Publications

Diffusive gas transport at high water contents and physiological water stress at low water contents limited atmospheric methane consumption rates during experimental manipulations of soil water content and water potential. Maximum rates of atmospheric methane consumption occurred at a soil water content of 25% (grams per gram [dry weight]) and a water potential of about - 0.2 MPa. In contrast, uptake rates were highest at a water content of 38% and a water potential of -0.03 MPa when methane was initially present at 200 ppm. Uptake rates of atmospheric and elevated methane decreased when water potentials were reduced by adding …

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Regulation Of Methane Oxidation In A Freshwater Wetland By Water Table Changes And Anoxia, Peter Roslev, Gary M. King Jan 1996

Regulation Of Methane Oxidation In A Freshwater Wetland By Water Table Changes And Anoxia, Peter Roslev, Gary M. King

Faculty Publications

The effects of water table fluctuations and anoxia on methane emission and methane oxidation were studied in a freshwater marsh. Seasonal aerobic methane oxidation rates varied between 15% and 76% of the potential diffusive methane flux (diffusive flux in the absence of aerobic oxidation). On an annual basis, approximately 43% of the methane diffusing into the oxic zone was oxidized before reaching the atmosphere. The highest methane oxidation was observed when the water table was below the peat surface. This was confirmed in laboratory experiments where short-term decreases in water table levels increased methane oxidation but also net methane emission. …

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Characterization Of The Denaturation And Renaturation Of Human Plasma Vitronectin Ii. Investigation Into The Mechanism Of Formation Of Multimers, Ping Zhuang, Huo Li, Jason G. Williams, Nancy V. Wagner, Dietmar Seiffert, Cynthia B. Peterson Jan 1996

Characterization Of The Denaturation And Renaturation Of Human Plasma Vitronectin Ii. Investigation Into The Mechanism Of Formation Of Multimers, Ping Zhuang, Huo Li, Jason G. Williams, Nancy V. Wagner, Dietmar Seiffert, Cynthia B. Peterson

Faculty Publications

Unfolding and refolding of plasma vitronectin appear irreversible under near physiological conditions, with rearrangements of disulfides and self-association to a multimeric form observed as prominent structural alterations which accompany denaturation. A mechanism for the folding reactions of vitronectin has been proposed (Zhuang, P., Blackburn, M. NPeterson, C. B. (1996) J. Biol. Chem. 270, 14323-14332) in which vitronectin acquires a partially folded intermediate structure which is highly prone to oligomerize into a multimeric form. Strongly oxidizing conditions adopted for refolding from urea were effective at preventing disulfide rearrangement which disrupts distal disulfides near the C terminus of the protein. Prohibiting disulfide …

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