Physical Sciences and Mathematics | Open Access Articles

Degree Of Adaptive Approximation, Ronald A. Devore, Ming Yu Xiang

Faculty Publications

We obtain various estimates for the error in adaptive approximation and also establish a relationship between adaptive approximation and free-knot spline approximation.

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Universal Scaling Of Nonlocal And Local Resistance Fluctuations In Small Wires, H. Haucke, S. Washburn, A. D. Benoit, C. P. Umbach, Richard A. Webb

Faculty Publications

Resistance fluctuations in small metal samples result from coherent transport of the carriers. The wave functions of the carriers extend into regions which are not accessible classically. We have directly measured the length dependence of the nonlocal magnetoresistance fluctuations in Sb and Au wires by studying regions of our samples separated from the classical current path by a distance L which varied from 3L_cphi down to 0.2L_cphi (where L_cphi is the phase coherence length for the carriers in the metal). These fluctuations decay exponentially with L/L_cphi. Measurements along the classical current paths scale more slowly …

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Norms Of Positive Operators On Lp-Spaces, Ralph Howard, Anton R. Schep

Faculty Publications

No abstract provided.

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A Scale Of Linear Spaces Related To The Lp Scale, S J. Dilworth

Faculty Publications

No abstract provided.

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Central And South America Gps Geodesy- Casa Uno, James N. Kellogg, Timothy H. Dixon

Faculty Publications

In January 1988, scientists from over 25 organizations in 13 countries and territories cooperated in the largest Global Positioning System (GPS) campaign in the world to date (Table 1). 43 GPS receivers collected approximately 590 station-days of data in America, Samoa, Australia, Canada, Colombia, Costa Rica, Ecuador, New Zealand, Norway, Panama, Sweden, United States, West Germany, and Venezuela. The experiment was entitled CASA UNO, an acronym for Central and South America -- and uno is the Spanish word for one, designating first epoch measurements. The CASA UNO experiment was the first civilian effort implementing a global GPS satellite tracking network. …

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The Extended Tracking Network And Indications Of Baseline Precision And Accuracy In The North Andes, Jeffrey T. Freymueller, James N. Kellogg

Faculty Publications

The CASA UNO Global Positioning System (GPS) experiment (January-February 1988) included an extended tracking network which covered three continents in addition to the network of scientific interest in Central and South America. The repeatability of long baselines (400-1000 km) in South America is improved by up to a factor of two in the horizontal vector baseline components by using tracking stations in the Pacific and Europe to supplement stations in North America. In every case but one, the differences between the mean solutions obtained using different tracking networks was equal to or smaller than day-to-day rms repeatabilities for the same …

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First Gps Baseline Results From The North Andes, James N. Kellogg, Jeffrey T. Freymueller, Timothy H. Dixon, Ruth E. Neilan, Clemente Ropain U., Sergio Camargo M., Benjamin Fernandez Ch., James L. Stowell, Anibal Salazar, Jaime Mora V., Luis Espin, Vernon Perdue, Leonard Leos

Faculty Publications

The CASA UNO GPS (Global Positioning System) experiment (January-February 1988) has provided the first epoch baseline measurements for the study of plate motions and crustal deformation in and around the North Andes. Two dimensional horizontal baseline repeatabilities are as good as 5 parts in 10⁸ for short baselines (100-1000km), and better than3 parts in 10⁸ for long baselines (>1000km). Vertical repeatabilities are typically 4 -6 cm, with a weak dependence on baseline length. The expected rate of plate convergence across the Colombia Trench is 6-8 cm/yr, which should be detectable by the repeat experiment planned for 1991. …

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On Two Function-Spaces Which Are Similar To L0, S J. Dilworth, D A. Trautman

Faculty Publications

No abstract provided.

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Rheology Of Aqueous Suspensions Of Polystyrene Latex Stabilized By Grafted Poly(Ethylene Oxide), Harry J. Ploehn, J. W. Goodwin

Faculty Publications

A water-soluble carbodiimide has been used to end-graft aminated poly (ethylene oxide)(PEO) chemically onto colloidal polystyrene particles. Two particle sizes (115 and 347 nm diameter) and two PEO molecular weights (112 000 and 615 000 g mol^–1) were combined to give suspensions with four different ratios of polymer layer thickness to particle radius. Electrophoresis demonstrated that the PEO was grafted, not just adsorbed. Dynamic light scattering showed that the adsorbed and grafted layers had similar structures and that non-ionic surfactant perturbed the PEO configurations. Steady shear and oscillatory rheometry indicated that long-ranged polymeric forces between particles governed the …

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A Note On Roe's Characterization Of The Sine Function, Ralph Howard

Faculty Publications

No abstract provided.

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Inulin-125I-Tyramine, An Improved Residualizing Label For Studies On Sites Of Catabolism Of Circulating Proteins, Janet L. Maxwell, John W. Baynes, Suzanne R. Thorpe

Faculty Publications

Residualizing labels for protein, such as dilactitol-125I-tyramine (125I-DLT) and cellobiitol-125I-tyramine, have been used to identify the tissue and cellular sites of catabolism of long-lived plasma proteins, such as albumin, immunoglobulins, and lipoproteins. The radioactive degradation products formed from labeled proteins are relatively large, hydrophilic, resistant to lysosomal hydrolases, and accumulate in lysosomes in the cells involved in degradation of the carrier protein. However, the gradual loss of the catabolites from cells (t1/2 approximately 2 days) has limited the usefulness of residualizing labels in studies on longer lived proteins. We describe here a higher molecular weight (Mr approximately 5000), more efficient …

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Subspaces Of Lp,Q, N L. Carothers, S J. Dilworth

Faculty Publications

We examine the subspace structure of the Lorentz function space Lp,q[0, oo). Our main result is that a subspace of Lp,q[0, oo), p ^ 2, q < oo,must either strongly embed in Lp[0,1] or contain a complemented copy of lq.

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Inequalities For Sums Of Independent Random Variables, N L. Carothers, S J. Dilworth

Faculty Publications

A moment inequality is proved for sums of independent random variables in the Lorentz spaces LPtq, thus extending an inequality of Rosenthal. The latter result is used in combination with a square function inequality to give a proof of a Banach space isomorphism theorem. Further moment inequalities are also proved.

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Oxidative Degradation Of Glucose Adducts To Protein: Formation Of 3-(NE-Lysino)-Lactic Acid From Model Compounds And Glycated Proteins, Mahtab U. Ahmed, John A. Dunn, Michael D. Walla, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

The chemistry of Maillard or browning reactions of glycated proteins is being studied in model systems in vitro in order to characterize potential reaction pathways and products in biological systems. In previous work with the Amadori rearrangement product N alpha-formyl-N epsilon-fructoselysine (fFL), an analog of glycated lysine residues in proteins, we showed that fFL was oxidatively cleaved between C-2 and C-3 of the carbohydrate chain to yield N epsilon-carboxymethyllysine (CML) and D-erythronic acid. We then detected CML in proteins glycated in vitro, as well as in human lens proteins and collagen in vivo (Ahmed, M. U., Thorpe, S. R., and …

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Experimental Study Of Nonlinear Conductance In Small Metallic Samples, Richard A. Webb, S. Washburn, C. P. Umbach

Faculty Publications

We have directly observed current-dependent, nonlinear contributions to the conductance fluctuations of phase-coherent metallic wires and loops. The fluctuations in the current-voltage curves are reproducible, asymmetric about I=0, and in qualitative agreement with theoretical predictions. In ac measurements, the nonlinear terms also generate large harmonic signals of the conductance fluctuations whose dependence on the drive current can be understood qualitatively. The spectra of harmonics from loops and wires have different dependences on the voltage across the sample.

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A Cytochemical Study Of The Transcriptional And Translational Regulation Of Nuclear Transition Protein 1 (Tp1), A Major Chromosomal Protein Of Mammalian Spermatids, Mohammad A. Heidaran, Richard M. Showman, Wilson Stephen Kistler

Faculty Publications

Immunocytochemical localization and in situ hybridization techniques were used to investigate the presence of spermatid nuclear transition protein 1 (TP1) and its mRNA during the various stages of spermatogenesis in the rat. A specific antiserum to TP1 was raised in a rabbit and used to show that TP1 is immunologically crossreactive among many mammals including humans. During spermatogenesis the protein appears in spermatids as they progress from step 12 to step 13, a period in which nuclear condensation is underway. The protein is lost during step 15. An asymmetric RNA probe generated from a TP1 cDNA clone identified TP1 mRNA …

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Hydrothermal Fluids And Petroleum In Surface Sediments Of Guaymas Basin, Gulf Of California: A Case Study, J. M. Gieskes, B. R. Simoneit, T. Brown, Timothy J. Shaw, Y. C. Wang, A. Magenheim

Faculty Publications

No abstract provided.

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Interpolation Of Besov-Spaces, Ronald A. Devore, Vasil A. Popova

Faculty Publications

We investigate Besov spaces and their connection with dyadic spline approximation in Lp(Omega), 0 < p (less than or equal to) infinity. Our main results are: the determination of the interpolation spaces between a pair of Besov spaces; an atomic decomposition for functions in a Besov space; the characterization of the class of functions which have certain prescribed degree of approximation by dyadic splines.

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Involutions On Banach Spaces And Reflexivity, S J. Dilworth

Faculty Publications

No abstract provided.

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The Twentieth Fermat Number Is Composite, Jeff Young, Duncan A. Buell

Faculty Publications

The twentieth Fermat number, F₂₀ = 2^{2^20} +1, has been proven composite by machine computation.

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Normal-Metal Aharonov-Bohm Effect In The Presence Of A Transverse Electric Field, S. Washburn, H. Schmid, D. Kern, Richard A. Webb

Faculty Publications

The effects of transverse electric fields on the conductance fluctuations in an Sb loop have been studied. We show that the electric field can be used to tune the position (or phase) of Aharonov-Bohm oscillations as well as to alter the aperiodic conductance fluctuation patterns. We disucss two mechanisms which might cause the observed dependence of the fluctuation pattern on transverse electric field. The first is the electrostatic Aharonov-Bohm effect, and the second is the spatial shifting of the electron trajectories by the electric field.

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Integer Squares With Constant Second Difference, Duncan A. Buell

Faculty Publications

The problem addressed is this: Do there exist nonconsecutive integers n₀, n₁, n₂, . . ., such that the second differences of the squares of the n_i are constant? Specifically, can that constant be equal to 2? A complete characterization of sequences of length four can be given. The question of whether or not sequences of length five exist is still open but the existence or nonexistence of such sequences can be described in a more algorithmic way than the simple statement of the problem.

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Observation Of An Oxygen Isotope Effect In Yba2Cu3O7, Kevin J. Leary, Hans Conrad Zur Loye, Steven W. Keller, Tanya A. Faltens, William K. Ham, James N. Michaels, Angelica M. Stacy

Faculty Publications

A small decrease in T_c of 0.3 K to 0.5 K is observed when as much as 90% of the ¹⁶O in YBa₂Cu₃O₇ is substituted with¹⁸O. This result is consistent with our observation that there is an oxygen isotope effect in La_1.85Sr_0.15CuO₄, but in contrast with previous reports that there is no isotope effect for YBa₂Cu₃O₇. This new result suggests that phonons play an important role in the electron-pairing mechanism in YBa₂Cu₃O₇.

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Sequentially Compact, Franklin-Rajagopalan Spaces, Peter J. Nyikos, J. E. Vaughan

Faculty Publications

No abstract provided.

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Observation Of An Isotope Shift In The Superconducting Transition Temperature Of La1.85Sr0.15Cuo4, Tanya A. Faltens, William K. Ham, Steven W. Keller, Kevin J. Leary, James N. Michaels, Angelica M. Stacy, Hans Conrad Zur Loye, Donald E. Morris, T W. Barbee Iii, Marvin L. Cohen, Cohen S. Hoen, A Zettl

Faculty Publications

An oxygen isotope shift is observed in superconducting La_1.85Sr_0.15CuO₄ when ¹⁸O is substituted partially for ¹⁶O; the superconducting transition temperature T_c is lowered by 0.3 to 1.0 K in different samples. We examine these results using conventioanl phonon-mediated BCS theory and conclude that, for La_1.85Sr_0.15CuO₄, phonons play an important role in the pairing mechanism.

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Search For Isotope Effect In Superconducting Y-Ba-Cu-O, L C. Bourne, M F. Crommie, A Zettl, Hans Conrad Zur Loye, S W. Keller, K L. Leary, Angelica M. Stacy, K J. Chang, Marvin L. Cohen, Donald E. Morris

Faculty Publications

An isotope effect has been searched for in the high-T_c, superconductor YBa₂Cu₃0_{7 —b} through substitution of ¹⁸0 for ¹⁶O. No shift in the superconducting transition temperature T, is observed by electrical resistivity or magnetic susceptibility measurements. We discuss the implications of this result for mechanisms of superconductivity in the high-T, oxides.

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Length-Independent Voltage Fluctuations In Small Devices, A. Benoit, C. P. Umbach, R. B. Laibowitz, Richard A. Webb

Faculty Publications

Conductance fluctuations in one-dimensional lines of length L shorter than the phase-coherence length L_φ are not universal but diverge as L^-2. Using the Onsager relations and voltage additivity, we show that the voltage fluctuations are independent of the distance between voltage probes. The antisymmetric (Hall-type) contribution to the voltage fluctuations is constant for all values of L. Measurements of the voltage fluctuations and correlation function between different regions in Au and Sb lines confirm these results.

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Effect Of Phosphate On The Kinetics And Specificity Of Glycation Of Protein, Nancy G. Watkins, Carolyn I. Neglia-Fisher, Daniel G. Dyer, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

The glycation (nonenzymatic glycosylation) of several proteins was studied in various buffiner os rder to assess the effects of buffering ions on the kinetics and specificity of glycation of protein. Incubation of RNase with glucose in phosphate buffer resulted in inactivation of the enzyme because of preferential modification of lysine residues ino r near the activsei te. In contrast, in the cationic buffers, 3-(N-morpholino)propanesulfonic acid and 3-(N-tris(hydroxymethyl)rnethylamino)- 2-hydroxypropanesulfonica cid, the kineticso f glycation of RNase were decreased 2- to 3-fold, there was a decrease in glycation of active site versus peripheral lysines, and the enzyme was resistant to inactivation by …

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Class Groups Of Quadratic Fields Ii, Duncan A. Buell

Faculty Publications

A computation has been made of the noncyclic class groups of imaginary quadratic fields Q(√-D) for even and odd discriminants - D from 0 to - 25000000. Among the results are that 95% of the class groups are cyclic, and that -11203620 and -18397407 are the first discriminants of imaginary quadratic fields for which the class group has rank three in the 5-Sylow subgroup. The latter was known to be of rank three; this computation demonstrates that it is the first odd discriminant of 5-rank three or more.

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Large Deviations For Processes With Independent Increments, James Lynch, Jayaram Sethuraman

Faculty Publications

Let X be a topological space and F denote the Borel σ-field in X. A family of probability measures {Pλ} is said to obey the large deviation principle (LDP) with rate function I(⋅) if Pλ(A) can be suitably approximated by exp{−λinfx∈AI(x)} for appropriate sets A in F. Here the LDP is studied for probability measures induced by stochastic processes with stationary and independent increments which have no Gaussian component. It is assumed that the moment generating function of the increments exists and thus the sample paths of such stochastic processes lie in the space of functions of bounded variation. The …

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Full-Text Articles in Physical Sciences and Mathematics

Degree Of Adaptive Approximation, Ronald A. Devore, Ming Yu Xiang

Faculty Publications

Universal Scaling Of Nonlocal And Local Resistance Fluctuations In Small Wires, H. Haucke, S. Washburn, A. D. Benoit, C. P. Umbach, Richard A. Webb

Faculty Publications

Norms Of Positive Operators On Lp-Spaces, Ralph Howard, Anton R. Schep

Faculty Publications

A Scale Of Linear Spaces Related To The Lp Scale, S J. Dilworth

Faculty Publications

Central And South America Gps Geodesy- Casa Uno, James N. Kellogg, Timothy H. Dixon

Faculty Publications

The Extended Tracking Network And Indications Of Baseline Precision And Accuracy In The North Andes, Jeffrey T. Freymueller, James N. Kellogg

Faculty Publications

First Gps Baseline Results From The North Andes, James N. Kellogg, Jeffrey T. Freymueller, Timothy H. Dixon, Ruth E. Neilan, Clemente Ropain U., Sergio Camargo M., Benjamin Fernandez Ch., James L. Stowell, Anibal Salazar, Jaime Mora V., Luis Espin, Vernon Perdue, Leonard Leos

Faculty Publications

On Two Function-Spaces Which Are Similar To L0, S J. Dilworth, D A. Trautman

Faculty Publications

Rheology Of Aqueous Suspensions Of Polystyrene Latex Stabilized By Grafted Poly(Ethylene Oxide), Harry J. Ploehn, J. W. Goodwin

Faculty Publications

A Note On Roe's Characterization Of The Sine Function, Ralph Howard

Faculty Publications

Inulin-125I-Tyramine, An Improved Residualizing Label For Studies On Sites Of Catabolism Of Circulating Proteins, Janet L. Maxwell, John W. Baynes, Suzanne R. Thorpe

Faculty Publications

Subspaces Of Lp,Q, N L. Carothers, S J. Dilworth

Faculty Publications

Inequalities For Sums Of Independent Random Variables, N L. Carothers, S J. Dilworth

Faculty Publications

Oxidative Degradation Of Glucose Adducts To Protein: Formation Of 3-(NE-Lysino)-Lactic Acid From Model Compounds And Glycated Proteins, Mahtab U. Ahmed, John A. Dunn, Michael D. Walla, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

Experimental Study Of Nonlinear Conductance In Small Metallic Samples, Richard A. Webb, S. Washburn, C. P. Umbach

Faculty Publications

A Cytochemical Study Of The Transcriptional And Translational Regulation Of Nuclear Transition Protein 1 (Tp1), A Major Chromosomal Protein Of Mammalian Spermatids, Mohammad A. Heidaran, Richard M. Showman, Wilson Stephen Kistler

Faculty Publications

Hydrothermal Fluids And Petroleum In Surface Sediments Of Guaymas Basin, Gulf Of California: A Case Study, J. M. Gieskes, B. R. Simoneit, T. Brown, Timothy J. Shaw, Y. C. Wang, A. Magenheim

Faculty Publications

Interpolation Of Besov-Spaces, Ronald A. Devore, Vasil A. Popova

Faculty Publications

Involutions On Banach Spaces And Reflexivity, S J. Dilworth

Faculty Publications

The Twentieth Fermat Number Is Composite, Jeff Young, Duncan A. Buell

Faculty Publications

Normal-Metal Aharonov-Bohm Effect In The Presence Of A Transverse Electric Field, S. Washburn, H. Schmid, D. Kern, Richard A. Webb

Faculty Publications

Integer Squares With Constant Second Difference, Duncan A. Buell

Faculty Publications

Observation Of An Oxygen Isotope Effect In Yba2Cu3O7, Kevin J. Leary, Hans Conrad Zur Loye, Steven W. Keller, Tanya A. Faltens, William K. Ham, James N. Michaels, Angelica M. Stacy

Faculty Publications

Sequentially Compact, Franklin-Rajagopalan Spaces, Peter J. Nyikos, J. E. Vaughan

Faculty Publications

Faculty Publications

Search For Isotope Effect In Superconducting Y-Ba-Cu-O, L C. Bourne, M F. Crommie, A Zettl, Hans Conrad Zur Loye, S W. Keller, K L. Leary, Angelica M. Stacy, K J. Chang, Marvin L. Cohen, Donald E. Morris

Faculty Publications

Length-Independent Voltage Fluctuations In Small Devices, A. Benoit, C. P. Umbach, R. B. Laibowitz, Richard A. Webb

Faculty Publications

Effect Of Phosphate On The Kinetics And Specificity Of Glycation Of Protein, Nancy G. Watkins, Carolyn I. Neglia-Fisher, Daniel G. Dyer, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

Class Groups Of Quadratic Fields Ii, Duncan A. Buell

Faculty Publications

Large Deviations For Processes With Independent Increments, James Lynch, Jayaram Sethuraman

Faculty Publications