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Relative Rates Of Molecular Evolution In Rodents And Their Symbionts., Theresa Ann Spradling Jan 1997

Relative Rates Of Molecular Evolution In Rodents And Their Symbionts., Theresa Ann Spradling

LSU Historical Dissertations and Theses

The focus of this dissertation is the relative tempo of molecular evolution among organisms of varying levels of relatedness. Because this is a rapidly expanding area of research, Chapter 1 is devoted to a review of the current state of knowledge on rates of molecular evolution. In Chapter 2, I present an analysis of relative rates of evolution among several distantly related rodents. The heterogeneity in rate of evolution of the cytochrome b gene observed here cannot be explained by metabolic rate, body size, generation time, or nucleotide-generation time. Likewise, there is no evidence that these differences in rate of …

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Pseudospin Transformation Of Physical Operators, A. L. Blokhin, C. Bahri, J. P. Draayer Dec 1996

Pseudospin Transformation Of Physical Operators, A. L. Blokhin, C. Bahri, J. P. Draayer

Faculty Publications

A procedure for applications of the pseudospin transformation within the framework of nuclear oscillator shell model is developed. It is valid for operators expressed in terms of single-particle variables and is based on permutation rules for special rotational invariants. The procedure is applied to a number of physical operators including several rotational scalars, the spin and orbital momenta, and the quadrupole moment. An algorithm for generating an approximation to the pseudospin transformation, which gives a simple and accurate expression for dominant parts of required transforms, is also given. The algebras associated with pseudospin transformations are discussed. © 1996 IOP Publishing …

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Activation Of Δ-Globin Gene Expression By Erythroid Krupple-Like Factor: A Potential Approach For Gene Therapy Of Sickle Cell Disease, David Donze, Paxson H. Jeancake, Tim M. Townes Nov 1996

Activation Of Δ-Globin Gene Expression By Erythroid Krupple-Like Factor: A Potential Approach For Gene Therapy Of Sickle Cell Disease, David Donze, Paxson H. Jeancake, Tim M. Townes

Faculty Publications

Hemoglobin A2 (HbA2; α2δ2) is a powerful inhibitor of HbS (α2β2/(S) polymerization. However, HbA2 levels are normally low in sickle cell patients. We show that a major reason for low δ-globin gene expression is the defective CACCC box at -90 in the δ-globin promoter. When the CACCC box defect in δ is corrected, expression of an HS2 δ/Luciferase reporter is equivalent to HS2 β/Luciferase. Erythroid Krupple-like factor (EKLF), which binds to the CACCC box of the β-globin gene and activates high-level expression, does not bind to the normal δ-globin promoter. Our goal is to design a modified EKLF that binds …

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Nonequilibrium Critical Dynamics Of A Three Species Monomer-Monomer Model, Kevin E. Bassler, Dana A. Browne Nov 1996

Nonequilibrium Critical Dynamics Of A Three Species Monomer-Monomer Model, Kevin E. Bassler, Dana A. Browne

Faculty Publications

We study a three species monomer-monomer catalytic surface reaction model with a reactive steady state bordered by three equivalent unreactive phases where the surface is saturated with one species. The transition from the reactive to a saturated phase shows directed percolation critical behavior. Each pair of these reactive-saturated phase boundaries joins at a bicritical point where the universal behavior is in the even branching annihilating random walk class. We find the crossover exponent from bicritical to critical behavior and a new exponent associated with the bicritical interface dynamics. © 1996 The American Physical Society.

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Lumières, Fall 1996, Louisiana State University And Agricultural & Mechanical College Oct 1996

Lumières, Fall 1996, Louisiana State University And Agricultural & Mechanical College

Friends of the LSU Libraries

The bi-annual newsletters from the Friends of the Library contain information about upcoming and recent events, descriptions of new collections, a list of members, and occasional obituaries, which inform members of the news and needs of the LSU Libraries.

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Large-Area Sub-Millimeter Resolution Cdznte Strip Detector For Astronomy, J. R. Macri, B. A. Apotovsky, J. F. Butler, M. L. Cherry, B. K. Dann, F. P. Doty, T. G. Guzik, M. L. Mcconnell, J. M. Ryan Oct 1996

Large-Area Sub-Millimeter Resolution Cdznte Strip Detector For Astronomy, J. R. Macri, B. A. Apotovsky, J. F. Butler, M. L. Cherry, B. K. Dann, F. P. Doty, T. G. Guzik, M. L. Mcconnell, J. M. Ryan

Faculty Publications

We report performance measurements of a sub-millimeter resolution CdZnTe strip detector developed as a prototype for astronomical instruments. The prototype is a 1.4 mm thick, 64 × 64 stripe CdZnTe array with 0.375 mm pitch in both dimensions. Pulse height spectra in orthogonal stripe coincidence mode were recorded at several energies. The room-temperature energy resolution is (FWHM) for 122 keV photons with a peak-to-valley ratio >5:1. We also demonstrate spatial resolution capabilities finer than the stripe pitch.

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Dijet Angular Distributions In Direct And Resolved Photoproduction 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, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, R. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, R. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari Sep 1996

Dijet Angular Distributions In Direct And Resolved Photoproduction 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, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, R. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, R. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari

Faculty Publications

Jet photoproduction, where the two highest transverse energy (ETjet) jets have ETjet above 6 GeV and a jet-jet invariant mass above 23 GeV, has been studied with the ZEUS detector at the HERA ep collider. Resolved and direct photoproduction samples have been separated. The cross section as a function of the angle between the jet-jet axis and the beam direction in the dijet rest frame has been measured for the two samples. The measured angular distributions differ markedly from each other. They agree with the predictions of QCD calculations, where the different angular distributions reflect the different spins of the …

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Observation Of Events With An Energetic Forward Neutron In Deep Inelastic Scattering 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, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, R. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, R. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari Sep 1996

Observation Of Events With An Energetic Forward Neutron In Deep Inelastic Scattering 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, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, R. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, R. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari

Faculty Publications

In deep inelastic neutral current scattering of positrons and protons at the center of mass energy of 300 GeV, we observe, with the ZEUS detector, events with a high energy neutron produced at very small scattering angles with respect to the proton direction. The events constitute a fixed fraction of the deep inelastic, neutral current event sample independent of Bjorken x and Q2 in the range 3 · 10-4 < xBJ < 6 · 10-3 and 10 < Q2 < 100 GeV2.

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Theory And Operation Of Continuous Flow Systems For The Study Of Benthic-Pelagic Coupling, Tina Miller-Way, Robert R. Twilley Sep 1996

Theory And Operation Of Continuous Flow Systems For The Study Of Benthic-Pelagic Coupling, Tina Miller-Way, Robert R. Twilley

Faculty Publications

Continuous flow systems have not been widely used in the study of benthic-pelagic coupling in marine systems. This paper discusses the theoretical and practical use of continuous flow sysrems for the study of benthic exchange processes and presents the results of experiments which compared continuous flow (open) and closed (batch) systems and investigated the sensitivity of exchange rates to residence times in a continuous flow system. Continuous flow systems minimize the problem of environmental dependency of benthic-pelagic exchange rates by maintaining initial experimental conditions throughout an incubation. However, the selection of a supply rate (i.e. residence time) is critical in …

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An Examination Of The Digital Synthesiser As A Tool For Score Study As Measured By Undergraduate Music Education Majors' Responses To A Performance Error Detection Task, John A. B. Palmer Aug 1996

An Examination Of The Digital Synthesiser As A Tool For Score Study As Measured By Undergraduate Music Education Majors' Responses To A Performance Error Detection Task, John A. B. Palmer

LSU Historical Dissertations and Theses

The purpose of this study was to design and implement an approach to score study involving a digital synthsizer as a means to develop an aural image of the music. Specifically, the procedure entailed line by line recording of William Latham' s Three Chorale Preludes for band followed by a sequence of listening activities using the synthesized recording. Subjects (N = 23) were divided into 3 groups, assigned one of three preludes, and given a treatment specific to the assigned prelude. Subjects' pre- and posttest aural skills were measured by way of a test of pitch and rhythm performance error …

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Progress In The Development Of Large Area Sub-Millimeter Resolution Cdznte Strip Detectors, J. R. Macri, D. V. Boykin, K. Larson, M. Mayer, M. L. Mcconnell, J. M. Ryan, M. L. Cherry, T. G. Guzik, B. A. Apotovsky, J. F. Butler, F. P. Doty, C. L. Lingren Jul 1996

Progress In The Development Of Large Area Sub-Millimeter Resolution Cdznte Strip Detectors, J. R. Macri, D. V. Boykin, K. Larson, M. Mayer, M. L. Mcconnell, J. M. Ryan, M. L. Cherry, T. G. Guzik, B. A. Apotovsky, J. F. Butler, F. P. Doty, C. L. Lingren

Faculty Publications

We report progress in ongoing measurements of the performance of a sub-millimeter pitch CdZnTe strip detector developed as a prototype for astronomical instruments. Strip detectors can be used to provide two-dimensional position resolution with fewer electronic channels than pixellated arrays. Arrays of this type are under development for the position-sensitive image plane detector for a coded-aperture telescope operating in the hard x-ray range of 20-200 keV. The prototype is a 1.5 mm thick, 64 x 64 orthogonal stripe CdZnTe detector of 0.375 mm pitch in both dimensions, approximately one square inch of sensitive area. In addition to energy and spatial …

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Measurement Of The Reaction Γ*P→Φp In Deep Inelastic E+P Scattering 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, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, R. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, R. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari Jul 1996

Measurement Of The Reaction Γ*P→Φp In Deep Inelastic E+P Scattering 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, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, R. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, R. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari

Faculty Publications

The production of φ mesons in the reaction e+p → e+φp (φ → K+K-), for 7 < Q2 < 25 GeV2 and for virtual photon-proton centre of mass energies (W) in the range 42-134 GeV, has been studied with the ZEUS detector at HERA. When compared to lower energy data at similar Q2, the results show that the γp → p0p cross section rises strongly with W. This behaviour is similar to that previously found for the γ*p → p0p cross section. This strong dependence cannot be explained by production through soft pomeron exchange. It is, however, consistent with perturbative QCD expectations, where it reflects the rise of the gluon momentum density in the proton at small x. The ratio of σ(φ)/σ(p0), which has previously been determined by ZEUS to be 0.065 ± 0.013 (stat.) in photoproduction at a mean W of 70 GeV, is measured to be 0.18 ± 0.05 (stat.) ± 0.03 (syst.) at a mean Q2 of 12.3 GeV2 and mean W of ≈ 100 GeV and is thus approaching at large Q2 the value of 2/9 predicted from the quark charges of the vector mesons and a flavour independent production mechanism.

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Louisiana Agriculture Magazine, Summer 1996, Lsu Agricultural Experiment Station Jul 1996

Louisiana Agriculture Magazine, Summer 1996, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.

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Response Of Sedimentary Bacteria In A Louisiana Salt Marsh To Contamination By Diesel Fuel, Kevin R. Carman, Jay C. Means, Steven C. Pomarico Jun 1996

Response Of Sedimentary Bacteria In A Louisiana Salt Marsh To Contamination By Diesel Fuel, Kevin R. Carman, Jay C. Means, Steven C. Pomarico

Faculty Publications

In a 28 d microcosm study, we examined the effects of diesel-contaminated sediment on the sedimentary bacterial community of a Louisiana (USA) salt marsh that has been chronically exposed to petroleum hydrocarbons for decades. Diesel contaminants in microcosms as determined from polycyclic aromatic hydrocarbon (PAH) concentration ranged from 0.55 to 55 ppm (dry weight). Bacterial metabolism (incorporation of 14C-acetate and 3H-leucine) and bacterial abundance were not affected by diesel-contaminated sediment at any concentration. Bacterial degradation of 14C-phenanthrene, however, increased in direct proportion to the amount of diesel- contaminated sediment added. Ambient sediment also exhibited significant capacity to degrade PAH. The …

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Determinants Of Hypertension In West Africa: Contribution Of Anthropometric And Dietary Factors To Urban-Rural And Socioeconomic Gradients, Jay S. Kaufman, Eme E. Owoaje, Sherman A. James, Charles N. Rotimi, Richard S. Cooper Jun 1996

Determinants Of Hypertension In West Africa: Contribution Of Anthropometric And Dietary Factors To Urban-Rural And Socioeconomic Gradients, Jay S. Kaufman, Eme E. Owoaje, Sherman A. James, Charles N. Rotimi, Richard S. Cooper

Faculty Publications

The determinants of hypertension in West Africa have not been well defined. The authors sampled 598 participants aged 45 years or more from a recent population-based survey in southwest Nigeria (190 rural men and women, 205 urban poor men and women, and 203 retired railway workmen). The estimated mean age was 61 (10) years. Mean pressures were low relative to westernized societies: systolic blood pressure = 124 (24) mmHg, diastolic blood pressure = 72 (13) mmHg. Both men and women were remarkably lean: body mass index = 21.3 (3.6) and 23.0 (5.2) kg/m2, respectively. Hypertension prevalence increased across the gradient …

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Measurement Of Elastic Φ Photoproduction 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, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, R. 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 Jun 1996

Measurement Of Elastic Φ Photoproduction 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, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, R. 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

The production of φ mesons in the reaction e+p → e+φp (φ → K+K-) at a median Q2 of 10-4 GeV2 has been studied with the ZEUS detector at HERA. The differential φ photoproduction cross section dσ/dt has an exponential shape and has been determined in the kinematic range 0.1 < |t| < 0.5 GeV2 and 60 < W < 80 GeV. An integrated cross section of σγp→φp = 0.96 ± 0.19+0.21-.18 μb has been obtained by extrapolating to t = 0. When compared to lower energy data, the results show a weak energy dependence of both σγp→φp and the slope of the t distribution. The φ decay angular distributions are consistent with s-channel helicity conservation. From lower energies to HERA energies, the features of φ photoproduction are compatible with those of a soft diffractive process.

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Role Of The Environment In Chaotic Quantum Dynamics, B. S. Helmkamp, D. A. Browne May 1996

Role Of The Environment In Chaotic Quantum Dynamics, B. S. Helmkamp, D. A. Browne

Faculty Publications

We study how the interaction with an external incoherent environment induces a crossover from quantum to classical behavior for a particle whose classical motion is chaotic. Posing the problem in the semiclassical regime for weak bath coupling, we find that noise rather than dissipation is primarily responsible for the dephasing that leads to the quantum inhibition of mixing. However, the noise is also shown to inhibit the mixing by enhancing paths that interfere coherently. © 1996 The American Physical Society.

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Dna Sequences Of Alu Elements Indicate A Recent Replacement Of The Human Autosomal Genetic Complement, Alec Knight, Mark A. Batzer, Mark Stoneking, Hemant K. Tiwari, W. Douglas Scheer, Rene J. Herrera, Prescott L. Deininger Apr 1996

Dna Sequences Of Alu Elements Indicate A Recent Replacement Of The Human Autosomal Genetic Complement, Alec Knight, Mark A. Batzer, Mark Stoneking, Hemant K. Tiwari, W. Douglas Scheer, Rene J. Herrera, Prescott L. Deininger

Faculty Publications

DNA sequences of neutral nuclear autosomal loci, compared across diverse human populations, provide a previously untapped perspective into the mode and tempo of the emergence of modern humans and a critical comparison with published clonally inherited mitochondrial DNA and Y chromosome measurements of human diversity. We obtained over 55 kilobases of sequence from three autosomal loci encompassing Alu repeats for representatives of diverse human populations as well as orthologous sequences for other hominoid species at one of these loci. Nucleotide diversity was exceedingly low. Most individuals and populations were identical. Only a single nucleotide difference distinguished presumed ancestral alleles from …

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Rapidity Gaps Between Jets In Photoproduction 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, R. Bruni, G. Cara Romeo, G. Castellini, M. Chiarini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, R. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam, R. Nania, C. Nemoz, F. Palmonari Feb 1996

Rapidity Gaps Between Jets In Photoproduction 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, R. Bruni, G. Cara Romeo, G. Castellini, M. Chiarini, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, I. Gialas, R. Giusti, G. Iacobucci, G. Laurenti, G. Levi, A. Margotti, T. Massam, R. Nania, C. Nemoz, F. Palmonari

Faculty Publications

Photoproduction events which have two or more jets have been studied in the Wγp range 135 GeV < Wγp < 280 GeV with the ZEUS detector at HERA. A class of events is observed with little hadronic activity between the jets. The jets are separated by pseudorapidity intervals (Δη) of up to four units and have transverse energies greater than 6 GeV. A gap is defined as the absence between the jets of particles with transverse energy greater than 300 MeV. The fraction of events containing a gap is measured as a function of Δη. It decreases exponentially as expected for processes in which colour is exchanged between the jets, up to a value of Δη ∼ 3, then reaches a constant value of about 0.1. The excess above the exponential fall-off can be interpreted as evidence for hard diffractive scattering via a strongly interacting colour singlet object.

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Hydrologic Restoration Of Coastal Wetlands, R. Eugene Turner, R. R. Lewiss Iii Jan 1996

Hydrologic Restoration Of Coastal Wetlands, R. Eugene Turner, R. R. Lewiss Iii

Faculty Publications

Hydrologic modification of coastal wetlands is pervasive, continuing and longstanding in the US. Appreciation for the subtleties of the direct and indirect effects of hydrologic changes on emergent vegetation, soils and co-dependent flora and fauna is contributing to restoration efforts. However the results of wetland restoration/rehabilitation are mostly empirical, rather than scientific in understanding. Science is contributing to the management interest by providing documentation of the past and present failures and successes, and, unveiling the fundamental understanding necessary to move from one wetland to another in an informed and adaptable manner. The papers in this volume are introduced within this …

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Efficient Long-Pcr Site-Specific Mutagenesis Of A High Gc Template, Vladimir Chouljenko, Sukhanya Jayachandra, Galina Rybachuk, Konstantin G. Kousoulas Jan 1996

Efficient Long-Pcr Site-Specific Mutagenesis Of A High Gc Template, Vladimir Chouljenko, Sukhanya Jayachandra, Galina Rybachuk, Konstantin G. Kousoulas

Faculty Publications

A long-PCR method was developed for the efficient site-specific mutagenesis of herpes simplex virus (HSV-1) DNA fragments with high GC content. In this protocol, a PCR product was partially extended first using a cloned DNA fragment. The final mutagenized fragment was produced after a second extension using another PCR product and final amplification using external primers. The sequential use of two extension reduction increased the predicted frequency of the engineered mutation in the final product to 100%. This method was used to generate a mutated glycoprotein K (gK) gene specified by HSV-1. A recombinant virus that carried the mutated gK …

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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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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 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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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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