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Articles 3061 - 3090 of 3102

Full-Text Articles in Physical Sciences and Mathematics

P-Selectin Or Intercellular Adhesion Molecule (Icam)-1 Deficiency Substantially Protects Against Atherosclerosis In Apolipoprotein E-Deficient Mice, Robert G. Collins, Rizwan Velji, Natalia V. Guevara, M. John Hicks, Lawrence Chan, Arthur L. Beaudet Jan 2000

P-Selectin Or Intercellular Adhesion Molecule (Icam)-1 Deficiency Substantially Protects Against Atherosclerosis In Apolipoprotein E-Deficient Mice, Robert G. Collins, Rizwan Velji, Natalia V. Guevara, M. John Hicks, Lawrence Chan, Arthur L. Beaudet

Physics & Astronomy Faculty Publications

The expression of leukocyte and endothelial cell adhesion molecules (CAMs) is essential for the emigration of leukocytes during an inflammatory response. The importance of the inflammatory response in the development of atherosclerosis is indicated by the increased expression of adhesion molecules, proinflammatory cytokines, and growth factors in lesions and lesion-prone areas and by protection in mice deficient in various aspects of the inflammatory response. We have quantitated the effect of deficiency for intercellular adhesion molecule (ICAM)-1, P-selectin, or E-selectin on atherosclerotic lesion formation at 20 wk of age in apolipoprotein (apo) E(- /-) (deficient) mice fed a normal chow diet. …

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Robust Test For Detecting Nonstationarity In Data From Gravitational Wave Detectors, Soumya Mohanty Jan 2000

Robust Test For Detecting Nonstationarity In Data From Gravitational Wave Detectors, Soumya Mohanty

Physics & Astronomy Faculty Publications

It is difficult to choose detection thresholds for tests of nonstationarity that assume a priori a noise model if the data are statistically uncharacterized to begin with. This is a potentially serious problem when an automated analysis is required, as would be the case for the huge data sets that large interferometric gravitational wave detectors will produce. A solution is proposed in the form of a robust time-frequency test for detecting nonstationarity whose threshold for a specified false alarm rate is almost independent of the statistical nature of the ambient stationary noise. The efficiency of this test in detecting bursts …

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The Hî² Index As An Age Indicator Of Old Stellar Systems: The Effects Of Horizontal-Branch Stars, Hyun Chul Lee, Suk Jin Yoon, Young Wook Lee Jan 2000

The Hî² Index As An Age Indicator Of Old Stellar Systems: The Effects Of Horizontal-Branch Stars, Hyun Chul Lee, Suk Jin Yoon, Young Wook Lee

Physics & Astronomy Faculty Publications

The strength of the Hβ index is computed for the integrated spectra of model globular clusters from the evolutionary population synthesis. For the first time, these models take into account the detailed systematic variation of horizontal-branch (HB) morphology with age and metallicity. Our models show that the Hβ index is significantly affected by the presence of blue HB stars. Because of the contribution from blue HB stars, the Hβ does not monotonically decrease as metallicity increases at a given age. Instead, it reaches a maximum strength when the distribution of HB stars is centered around 9500 K, the temperature at …

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Critical Adsorption On Defects In Ising Magnets And Binary Alloys, Andreas Hanke Jan 2000

Critical Adsorption On Defects In Ising Magnets And Binary Alloys, Andreas Hanke

Physics & Astronomy Faculty Publications

Long-range correlations in a magnet close to its critical point or in a binary alloy close to a continuous order-disorder transition can substantially enhance the effect of local perturbations. It is demonstrated using a position-space renormalization procedure that quasi-one-dimensional defects which break the symmetry of the order parameter have pronounced effects: They cause long-range critical adsorption profiles and give rise to new universal critical exponents, which are identified and calculated using field-theoretical methods.

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Production Of The Subtropical Seagrass, Halodule Wrightii Aschers., In Lower Laguna Madre, Texas, Joseph L. Kowalski Dec 1999

Production Of The Subtropical Seagrass, Halodule Wrightii Aschers., In Lower Laguna Madre, Texas, Joseph L. Kowalski

Theses and Dissertations - UTB/UTPA

The autecology of shoal grass, Halodule wrightii Aschers., was studied at 1.2 m depth from June 1995 to February 1997 in Lower Laguna Madre (LLM), Texas. Halodule wrightii in LLM received about 47% surface irradiance, but otherwise displayed lower growth rates and biomass in nutrient-poor rhizosphere and water-column environments compared to H. wrightii populations in other Texas estuaries. High tissue N content and low C:N ratios belied low growth dynamics. Halodule wrightii in LLM is probably nutrient limited. A high nutrient demand by H. wrightii in a nutrient-poor environment may explain, in part, its gradual displacement by Thalassia testudinum and …

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Gravitational Radiation From Globular Clusters, M. Benacquista Jul 1999

Gravitational Radiation From Globular Clusters, M. Benacquista

Physics & Astronomy Faculty Publications

Space-based gravitational wave detectors will have the ability to observe continuous low-frequency gravitational radiation from binary star systems. They can determine the direction to continuous sources with an angular resolution approaching tens of arcminutes. This resolution should be sufficient to identify binary sources as members of some nearby globular clusters. Thus, gravitational radiation can be used to determine the population of hard binaries in globular clusters. For particularly hard binaries, the orbital period may change as a result of gravitational wave emission. If one of these binaries can be identified with a globular cluster, then the distance to that cluster …

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The Weierstrass–Enneper System For Constant Mean Curvature Surfaces And The Completely Integrable Sigma Model, Paul Bracken, A. M. Grundland, L. Martina Jun 1999

The Weierstrass–Enneper System For Constant Mean Curvature Surfaces And The Completely Integrable Sigma Model, Paul Bracken, A. M. Grundland, L. Martina

School of Mathematical & Statistical Sciences Faculty Publications

The integrability of a system which describes constant mean curvature surfaces by means of the adapted Weierstrass–Enneper inducing formula is studied. This is carried out by using a specific transformation which reduces the initial system to the completely integrable two-dimensional Euclidean nonlinear sigma model. Through the use of the apparatus of differential forms and Cartan theory of systems in involution, it is demonstrated that the general analytic solutions of both systems possess the same degree of freedom. Furthermore, a new linear spectral problem equivalent to the initial Weierstrass–Enneper system is derived via the method of differential constraints. A new procedure …

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Role Of Reactive Oxygen Species In Mercapto-Methylimidazole-Induced Gastric Acid Secretion And Stress-Induced Gastric Ulceration, Uday Bandyopadhyay, Dipak Das, Debasish Bandyopadhyay, Mrinalini Bhattacharjee, Ranajit K. Banerjee Jan 1999

Role Of Reactive Oxygen Species In Mercapto-Methylimidazole-Induced Gastric Acid Secretion And Stress-Induced Gastric Ulceration, Uday Bandyopadhyay, Dipak Das, Debasish Bandyopadhyay, Mrinalini Bhattacharjee, Ranajit K. Banerjee

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

The objective of the present study is to delineate the role of reactive oxygen species in drug-induced gastric hyperacidity and stress-induced gastric ulceration. We reported earlier that mercaptomethylimidazole (MMI), an antithyroid drug, induces gastric acid (HCl) secretion partially through H2receptor activation of the parietal cell by histamine release and partially through an intracellular mechanism. While studying the latter, MMI-induced acid secretion was found to correlate well with the inactivation of the peroxidase, an important H2O2metabolizing enzyme of the mucosa. MMI activates the isolated parietal cell for acid secretion, which is sensitive to omeprazole. Peroxidase and catalase activity of the isolated …

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Critical Adsorption On Curved Objects, Andreas Hanke, S. Dietrich Jan 1999

Critical Adsorption On Curved Objects, Andreas Hanke, S. Dietrich

Physics & Astronomy Faculty Publications

A systematic field-theoretical description of critical adsorption on curved objects such as spherical or rodlike colloidal particles immersed in a fluid near criticality is presented. The temperature dependence of the corresponding order parameter profiles and of the excess adsorption are calculated explicitly. Critical adsorption on elongated rods is substantially more pronounced than on spherical particles. It turns out that, within the context of critical phenomena in confined geometries, critical adsorption on a microscopically thin ‘‘needle’’ represents a distinct universality class of its own. Under favorable conditions the results are relevant for the flocculation of colloidal particles.

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Observational Limit On Gravitational Waves From Binary Neutron Stars In The Galaxy, B. Allen, J. K. Blackburn, J. D. Creighton, Teviet Creighton Jan 1999

Observational Limit On Gravitational Waves From Binary Neutron Stars In The Galaxy, B. Allen, J. K. Blackburn, J. D. Creighton, Teviet Creighton

Physics & Astronomy Faculty Publications

Using optimal matched filtering, we search 25 hours of data from the LIGO 40-m prototype laser interferometric gravitational-wave detector for gravitational-wave chirps emitted by coalescing binary systems within our Galaxy. This is the first test of this filtering technique on real interferometric data. An upper limit on the rate R of neutron star binary inspirals in our Galaxy is obtained: with 90% confidence, R<0.5h−1. Similar experiments with LIGO interferometers will provide constraints on the population of tight binary neutron star systems in the Universe.

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Critical Adsorption Near Edges, Andreas Hanke, M. Krech, F. Schlesener, S. Dietrich Jan 1999

Critical Adsorption Near Edges, Andreas Hanke, M. Krech, F. Schlesener, S. Dietrich

Physics & Astronomy Faculty Publications

Symmetry breaking surface fields give rise to nontrivial and long-ranged order parameter profiles for critical systems such as fluids, alloys, or magnets confined to wedges. We discuss the properties of the corresponding universal scaling functions of the order parameter profile and the two-point correlation function, and determine the critical exponents η∥ and η⊥ for the so-called normal transition.

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Apex: Cross-Platform Analysis Program For Exafs, Nicholas Dimakis, Grant Bunker Jan 1999

Apex: Cross-Platform Analysis Program For Exafs, Nicholas Dimakis, Grant Bunker

Physics & Astronomy Faculty Publications

We have developed version 1.0 of a freely available (including source code) suite of basic X-Ray Absorption Fine Structure (XAFS) data analysis programs for data reduction and single scattering analysis. This package is based on the University of Washington (UW/NRL) Fortran 77 programs that are available on the International XAFS Society (IXS) database, complemented by a graphical TCL/TK scripting language based user interface which runs virtually unchanged between platforms, using the native look and feel of the corresponding platform. The package has been tested on MacOS 8.1, Linux, IRIX, Windows95 and NT. Particular emphasis is placed on simplicity, reliability, and …

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Polymer Depletion Effects Near Mesoscopic Particles, Andreas Hanke, E. Eisenriegler, S. Dietrich Jan 1999

Polymer Depletion Effects Near Mesoscopic Particles, Andreas Hanke, E. Eisenriegler, S. Dietrich

Physics & Astronomy Faculty Publications

The behavior of mesoscopic particles dissolved in a dilute solution of long, flexible, and nonadsorbing polymer chains is studied by field-theoretic methods. For spherical and cylindrical particles the solvation free energy for immersing a single particle in the solution is calculated explicitly. Important features are qualitatively different for self-avoiding polymer chains as compared with ideal chains. The results corroborate the validity of the Helfrich-type curvature expansion for general particle shapes and allow for quantitative experimental tests. For the effective interactions between a small sphere and a wall, between a thin rod and a wall, and between two small spheres, quantitative …

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Rapid Single- And Multiple-Scattering Exafs Debye-Waller Factor Calculations On Active Sites Of Metalloproteins, Nicholas Dimakis, M-Ali Al-Akhras, Grant Bunker Jan 1999

Rapid Single- And Multiple-Scattering Exafs Debye-Waller Factor Calculations On Active Sites Of Metalloproteins, Nicholas Dimakis, M-Ali Al-Akhras, Grant Bunker

Physics & Astronomy Faculty Publications

This paper describes recent results using our approach to calculating self-consistently single (SS) and multiple-scattering (MS) Debye- Waller factors (DWF) on active sites of metalloproteins. The calculation of MS DWF, together with the Feff7 program allows us to simulate ab-initio EXAFS spectra for a given temperature systems with no adjustable parameters. In our latest report (Dimakis N., and Bunker G., 1998) we calculate, using density functional and semiempirical approaches, the SS and MS DWF for small molecules and compared them to Raman, infrared and EXAFS spectra. In this report calculation of DWFs is done for tetrahedral Zn imidazole, a complex …

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Detecting An Association Between Gamma Ray And Gravitational Wave Bursts, Lee Samuel Finn, Soumya Mohanty, Joseph D. Romano Jan 1999

Detecting An Association Between Gamma Ray And Gravitational Wave Bursts, Lee Samuel Finn, Soumya Mohanty, Joseph D. Romano

Physics & Astronomy Faculty Publications

If γ-ray bursts (GRBs) are accompanied by gravitational wave bursts (GWBs) the correlated output of two gravitational wave detectors evaluated in the moments just prior to a GRB will differ from that evaluated at other times. We can test for this difference without prior knowledge of either the GWB wave form or the detector noise spectrum. With a model for the GRB source population and GWB spectrum we can put a limit on the in-band rms GWB signal amplitude. Laser-Interferometer Gravitational Wave Observatory I detector observations coincident with 1000 GRB observations could lead us to exclude with 95% confidence associated …

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Radio Pulse Properties Of The Millisecond Pulsar Psr J0437-4715. I. Observations At 20 Centimeters, F. A. Jenet, S. B. Anderson, V. M. Kaspi, T. A. Prince, S. C. Unwin May 1998

Radio Pulse Properties Of The Millisecond Pulsar Psr J0437-4715. I. Observations At 20 Centimeters, F. A. Jenet, S. B. Anderson, V. M. Kaspi, T. A. Prince, S. C. Unwin

Physics & Astronomy Faculty Publications

We present a total of 48 minutes of observations of the nearby, bright millisecond pulsar PSR J0437-4715 taken at the Parkes Observatory in Australia. The data were obtained at a central radio frequency of 1380 MHz using a high-speed tape recorder that permitted coherent Nyquist sampling of 50 MHz of bandwidth in each of two polarizations. Using the high time resolution available from this voltage recording technique, we have studied a variety of single-pulse properties, many for the first time in a millisecond pulsar. We show that individual pulses are broad band, have pulse widths ranging from ∼ 10 (∼ …

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On Different Integrable Systems Sharing The Same Nondynamical R-Matrix, Zhijun Qiao, Walter Strampp May 1998

On Different Integrable Systems Sharing The Same Nondynamical R-Matrix, Zhijun Qiao, Walter Strampp

School of Mathematical & Statistical Sciences Faculty Publications

In a recent paper @Zhijun Qiao and Ruguang Zhou, Phys. Lett. A 235, 35 ~1997!#, the amazing fact was reported that a discrete and a continuous integrable system share the same r-matrix with the interesting property of being nondynamical. Now, we present three further pairs of different continuous integrable systems sharing the same r-matrix again being nondynamical. The first pair is the finite-dimensional constrained system ~FDCS! of the famous AKNS hierarchy and the Dirac hierarchy; the second pair is the FDCS of the well-known geodesic flows on the ellipsoid and the Heisenberg spin chain hierarchy; and the third pair is …

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Three Types Of Gamma-Ray Bursts, Soma Mukherjee, Eric D. Feigelson, Gutti Jogesh Babu, Flonn Murtagh, Chris Fralev, Adrian Raftery Jan 1998

Three Types Of Gamma-Ray Bursts, Soma Mukherjee, Eric D. Feigelson, Gutti Jogesh Babu, Flonn Murtagh, Chris Fralev, Adrian Raftery

Physics & Astronomy Faculty Publications

A multivariate analysis of gamma-ray burst (GRB) bulk properties is presented to discriminate between distinct classes of GRBs. Several variables representing burst duration, fluence, and spectral hardness are considered. Two multivariate clustering procedures are used on a sample of 797 bursts from the Third BATSE Catalog, a nonparametric average linkage hierarchical agglomerative clustering procedure validated with Wilks' Λ* and other multivariate analysis of variance tests and a parametric maximum likelihood model-based clustering procedure assuming multinormal populations calculated with the Expectation-Maximization algorithm and validated with the Bayesian Information Criterion. The two methods yield very similar results. The BATSE GRB population consists …

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Searching For Periodic Sources With Ligo, Patrick R. Brady, Teviet Creighton, Curt Cutler, Bernard F. Schutz Jan 1998

Searching For Periodic Sources With Ligo, Patrick R. Brady, Teviet Creighton, Curt Cutler, Bernard F. Schutz

Physics & Astronomy Faculty Publications

We investigate the computational requirements for all-sky, all-frequency searches for gravitational waves from spinning neutron stars, using archived data from interferometric gravitational wave detectors such as LIGO. These sources are expected to be weak, so the optimal strategy involves coherent accumulaton of signal-to-noise using Fourier transforms of long stretches of data (months to years). Earth-motion-induced Doppler shifts, and intrinsic pulsar spindown, will reduce the narrow-band signal-to-noise by spreading power across many frequency bins; therefore, it is necessary to correct for these effects before performing the Fourier transform. The corrections can be implemented by a parametrized model, in which one does …

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Critical Casimir Forces Between Spherical Particles In Fluids, Andreas Hanke, F. Schlesener, E. Eisenriegler, S. Dietrich Jan 1998

Critical Casimir Forces Between Spherical Particles In Fluids, Andreas Hanke, F. Schlesener, E. Eisenriegler, S. Dietrich

Physics & Astronomy Faculty Publications

Long-ranged correlations in a fluid close to its critical point Tc cause distinct forces between immersed colloidal particles and the container walls. We calculate such a force and its temperature dependence for the generic case of a spherical particle located at a distance D from a planar wall and find that the force attains a maximum at a temperature Tmax(D) above Tc, which facilitates quantitative experimental tests. The corresponding effective pair interaction between the colloidal particles themselves, potentially leading to aggregation, is also discussed.

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Hierarchical Search Strategy For The Detection Of Gravitational Waves From Coalescing Binaries: Extension To Post-Newtonian Waveforms, Soumya Mohanty Jan 1998

Hierarchical Search Strategy For The Detection Of Gravitational Waves From Coalescing Binaries: Extension To Post-Newtonian Waveforms, Soumya Mohanty

Physics & Astronomy Faculty Publications

The detection of gravitational waves from coalescing compact binaries would be a computationally intensive process if a single bank of template wave forms (one step search) is used. In an earlier paper we presented a detection strategy, called a two step search, that utilizes a hierarchy of template banks. It was shown that in the simple case of a family of Newtonian signals, an on-line two step search was ≃8 times faster than an on-line one step search (for the initial LIGO). In this paper we extend the two step search to the more realistic case of …

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Ab Initio Single- And Multiple-Scattering Exafs Debye-Waller Factors: Raman And Infrared Data, Nicholas Dimakis, Grant Bunker Jan 1998

Ab Initio Single- And Multiple-Scattering Exafs Debye-Waller Factors: Raman And Infrared Data, Nicholas Dimakis, Grant Bunker

Physics & Astronomy Faculty Publications

The extended x-ray-absorption fine structure (EXAFS) Debye-Waller factor is an essential term appearing in the EXAFS equation that accounts for the molecular structural and thermal disorder of a sample. Single- and multiple-scattering Debye-Waller factors must be known accurately to obtain quantitative agreement between theory and experiment. Since the total number of fitting parameters that can be varied is limited in general, data cannot support fitting of all relevant multiple-scattering Debye-Waller factors. Calculation of the Debye-Waller factors is typically done using the correlated Debye approximation, where a single parameter (Debye temperature) is varied. However, this procedure cannot account in general for …

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A Data Analysis Approach For Detecting Gravitational Waves From Psr 0437-4715, Soumya Mohanty, I. S. Heng, David Blair, S. Dhurandhar, M. Tovar, E. Ivanov Jan 1998

A Data Analysis Approach For Detecting Gravitational Waves From Psr 0437-4715, Soumya Mohanty, I. S. Heng, David Blair, S. Dhurandhar, M. Tovar, E. Ivanov

Physics & Astronomy Faculty Publications

A search for gravitational waves from the millisecond pulsar PSR 0437-4715 has been initiated using the bar detector NIOBE which is located at the University of Western Australia. We present a detailed report on the data analysis algorithm, called phase plane rotation, which will be used in this search. A discussion of the actual implementation of the algorithm is presented. The data analysis algorithm mentioned above has the advantage that it requires minimal changes to the already-existing data acquisition facility of NIOBE but, at the same time, it is as efficient as optimal filtering in detecting a signal. This …

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Magnetic Field Decay In Single Radio Pulsars: A Statistical Study, Soma Mukherjee, Ajit Kembhavi Jan 1997

Magnetic Field Decay In Single Radio Pulsars: A Statistical Study, Soma Mukherjee, Ajit Kembhavi

Physics & Astronomy Faculty Publications

We report on an extensive statistical study of single radio pulsar properties, which we undertook to estimate the decay timescale of pulsar magnetic fields. We synthesized a population of pulsars using assumed theoretical distributions of age, initial magnetic field, period of rotation, position, luminosity, and dispersion measure, taking into account the new distance model for pulsars as well as new velocity estimates. We also took into account the selection effects that characterize pulsar observations. We compared the simulated population with the observed single pulsar population using one- and two-dimensional Kolmogorov-Smirnov tests to obtain a lower bound of ∼160 Myr on …

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Large-Amplitude Solitary Waves In Finite Temperature Dusty Plasma, R. Roychoudhury, S. Mukherjee Jan 1997

Large-Amplitude Solitary Waves In Finite Temperature Dusty Plasma, R. Roychoudhury, S. Mukherjee

Physics & Astronomy Faculty Publications

Large-amplitude solitary waves in dusty plasma are investigated, taking into account the dusty particle temperature. It is shown that finite dusty temperature restricts the region for the existence of solitary waves.

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Macrophage-Mediated 15-Lipoxygenase Expression Protects Against Atherosclerosis Development, Jianhe Shen, Ed Herderick, J. Fredrick Cornhill, Eva Zsigmond, Han Seob Kim, Hartmut Kühn, Natalia V. Guevara, Lawrence Chan Nov 1996

Macrophage-Mediated 15-Lipoxygenase Expression Protects Against Atherosclerosis Development, Jianhe Shen, Ed Herderick, J. Fredrick Cornhill, Eva Zsigmond, Han Seob Kim, Hartmut Kühn, Natalia V. Guevara, Lawrence Chan

Physics & Astronomy Faculty Publications

Oxidative modification of LDL increases its atherogenicity, and 15- lipoxygenase (15-LO) has been implicated in the process. To address this issue, we generated transgenic rabbits that expressed 15-LO in a macrophage- specific manner and studied their susceptibility to atherosclerosis development when they were fed a high-fat, high-cholesterol (HFHC) diet (Teklad 0533 rabbit diet 7009 with 10% corn oil and 0.25% cholesterol) for 13.5 wk. Transgenic and nontransgenic rabbits developed similar degrees of hypercholesterolemia and had similar levels of triglyceride, VLDL, LDL, and HDL. Quantitative morphometric analysis of the aortic atherosclerosis indicated that the transgenic animals (n = 19) had significantly …

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Effective Characteristic Polynomials And Two-Point Pade Approximants As Summation Techniques For The Strongly Divergent Perturbation Expansions Of The Ground State Energies Of Anharmonic Oscillators, Jiri Cizek, Ernst Joachim Weniger, Paul Bracken, Vladimir Spirko Mar 1996

Effective Characteristic Polynomials And Two-Point Pade Approximants As Summation Techniques For The Strongly Divergent Perturbation Expansions Of The Ground State Energies Of Anharmonic Oscillators, Jiri Cizek, Ernst Joachim Weniger, Paul Bracken, Vladimir Spirko

School of Mathematical & Statistical Sciences Faculty Publications

Pade approximants are able to sum effectively the Rayleigh-Schrodinger perturbation series for the ground state energy of the quartic anharmonic oscillator, as well as the corresponding renormalized perturbation expansion [E.J. Weniger, J. Cizek, and F. Vinette, J. Math. Phys. 34, 571 (1993)]. In the sextic case, Pade approximants are still able to sum these perturbation series, but convergence is so slow that they are computationally useless. In the octic case, Pade approximants are not powerful enough and fail. On the other hand, the inclusion of only a few additional data from the strong coupling domain [E.J. Weniger, Ann. Phys. (N.Y.) …

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Polymers Interacting With Spherical And Rodlike Particles, E. Eisenriegler, Andreas Hanke, S. Dietrich Jan 1996

Polymers Interacting With Spherical And Rodlike Particles, E. Eisenriegler, Andreas Hanke, S. Dietrich

Physics & Astronomy Faculty Publications

The interaction of a long flexible polymer chain with mesoscopic particles of spherical or elongated cylindrical shape is investigated by field-theoretic methods using the polymer-magnet analogy. In the case that these particles are immersed in a dilute polymer solution and exhibit purely repulsive surfaces we study density profiles for monomers and chain ends near such a particle, the change of configurational entropy by immersing a particle into the solution, and the depletion interaction between a particle and a distant planar wall. Both ideal chains and chains with an excluded-volume interaction are considered. We also analyze particle surfaces with a short-ranged …

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Hierarchical Search Strategy For The Detection Of Gravitational Waves From Coalescing Binaries, Soumya Mohanty, S. Dhurandhar Jan 1996

Hierarchical Search Strategy For The Detection Of Gravitational Waves From Coalescing Binaries, Soumya Mohanty, S. Dhurandhar

Physics & Astronomy Faculty Publications

The detection of gravitational waves from coalescing compact binaries would be a computationally intensive process if a single bank of template wave forms (i.e., a one-step search) is used. We present, in this paper, a method which leads to a large reduction in the computational power required as compared to a one-step search. This method is a hierarchical search strategy involving two template banks. We show that the computational power required by such a two-step search, for an on-line detection of the one-parameter family of Newtonian signals, is 18 of that required when an on-line one-step search is used. This …

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A Survey For Millisecond Pulsars, P. S. Ray, S. E. Thorsett, F. A. Jenet, M. H. Van Kerkwuk, S. R. Kulkarni, T. A. Prince, J. S. Sandhu, D. J. Nice Jan 1996

A Survey For Millisecond Pulsars, P. S. Ray, S. E. Thorsett, F. A. Jenet, M. H. Van Kerkwuk, S. R. Kulkarni, T. A. Prince, J. S. Sandhu, D. J. Nice

Physics & Astronomy Faculty Publications

We have searched 960 square degrees of sky for radio pulsars, using the 305 m telescope at Arecibo, Puerto Rico. The 430 MHz survey reached a limiting sensitivity for slow pulsars of 0.7 mJy using a dual-polarization, 32 channel filter bank over 8 MHz of bandwidth. We have detected one new millisecond pulsar, 11 new slow pulsars, one previously known millisecond pulsar, and eight previously known slow pulsars. The new millisecond pulsar, PSR J2033 + 17, with a period of 5.9 ms, has been found to be in a binary system. The Keplerian circular orbital solution has a period of …

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