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Regularization, Pseudofunction, And Hadamard Finite Part, R. Estrada, R. P. Kanwal Jan 1989

Regularization, Pseudofunction, And Hadamard Finite Part, R. Estrada, R. P. Kanwal

Faculty Publications

First, we discuss and correlate the various types of regularizations available in the literature for the singular function H(x) xk, where k is an integer and H(x) is the Heaviside function. Then we present the corresponding regularization for the function r-k, where r is the radial distance in Rn. Thereafter, we express the recently discovered distributional derivatives of this function in terms of pseudofunctional language commonly used in the Coulomb, gravitational, and interparticle potentials where the function 1 r plays a fundamental role. © 1989.


On The Pierce-Birkhoff Conjecture Over Ordered Fields, Charles N. Delzell Jan 1989

On The Pierce-Birkhoff Conjecture Over Ordered Fields, Charles N. Delzell

Faculty Publications

No abstract provided.


Is Griggs Dead? Reflecting (Fearfully) On Wards Cove Packing Co. V. Atonio, Mack Player Jan 1989

Is Griggs Dead? Reflecting (Fearfully) On Wards Cove Packing Co. V. Atonio, Mack Player

Faculty Publications

No abstract provided.


The University Of Choice: Social Work Students At Uni, James G. Mccullagh Jan 1989

The University Of Choice: Social Work Students At Uni, James G. Mccullagh

Faculty Publications

The study examined expressed reasons for choosing the University of Northern Iowa (UNI) by undergraduate students majoring in social work there. Responses of 205 social work majors to a questionnaire found that these students chose UNI primarily because of location; size; cost; the presence of a social work program; to get a good education; to be with their friends; and to continue a family tradition. Other findings indicated that 44% of students had attended other colleges previously; that many students considered other majors before deciding on social work; that 84% of the students had been born in Iowa; that 50% …


Oxygen Reduction In A Proton Exchange Membrane Test Cell, S. J. Ridge, Ralph E. White, Y. Tsou, R. N. Beaver, G. A. Eisman Jan 1989

Oxygen Reduction In A Proton Exchange Membrane Test Cell, S. J. Ridge, Ralph E. White, Y. Tsou, R. N. Beaver, G. A. Eisman

Faculty Publications

Oxygen reduction in a gas-fed porous electrode attached to a proton exchange membrane is discussed. Experimental data and a mathematical model are presented for the test cell used. Various membrane and electrode assemblies were tested at different levels of platinum loading and Teflon® content. The model accounts for the diffusion and reaction of oxygen and the diffusion and reaction of hydrogen ions. Sulfuric acid was placed above the membrane in the test cell reservoir to provide a source of protons for the reduction of oxygen at the cathode. Based upon model predictions, it is shown that the transport of the …


A Comparison Of Newman's Numerical Technique And Deboor's Algorithm, D. A. Curtis, T. I. Evans, Ralph E. White Jan 1989

A Comparison Of Newman's Numerical Technique And Deboor's Algorithm, D. A. Curtis, T. I. Evans, Ralph E. White

Faculty Publications

No abstract provided.


Estimation Of Electrode Kinetic Parameters Of The Lithium/Thionyl Chloride Cell Using A Mathematical Model, T. I. Evans, Ralph E. White Jan 1989

Estimation Of Electrode Kinetic Parameters Of The Lithium/Thionyl Chloride Cell Using A Mathematical Model, T. I. Evans, Ralph E. White

Faculty Publications

A one-dimensional mathematical model for the lithium/thionyl chloride primary cell is used in conjunction with a parameter estimation technique, in order to estimate the electrode kinetic parameters of this electrochemical system. The electrode kinetic parameters include the anodic transfer coefficient and exchange current density of the lithium oxidation, a,1 and i0,1,ref; the cathodic transfer coefficient and the effective exchange current density of the thionyl chloride reduction, c,4 and a0i0,4,ref, and a morphology parameter, . The parameter estimation is performed on simulated data first in order to gain confidence in the method. Data reported in …


A Mathematical Model Of A Lithium/Thionyl Chloride Primary Cell, T. I. Evans, T. V. Nguyen, Ralph E. White Jan 1989

A Mathematical Model Of A Lithium/Thionyl Chloride Primary Cell, T. I. Evans, T. V. Nguyen, Ralph E. White

Faculty Publications

A one-dimensional mathematical model for the lithium/thionyl chloride primary cell has been developed to investigate methods of improving its performance and safety. The model includes many of the components of a typical lithium/thionyl chloride cell such as the porous lithium chloride film which forms on the lithium anode surface. The governing equations are formulated from fundamental conservation laws using porous electrode theory and concentrated solution theory. The model is used to predict one-dimensional, time dependent profiles of concentration, porosity, current, and potentialas well as cell temperature and voltage. When a certain discharge rate is required, the model can be used …


A Thermal Analysis Of A Spirally Wound Battery Using A Simple Mathematical Model, T. I. Evans, Ralph E. White Jan 1989

A Thermal Analysis Of A Spirally Wound Battery Using A Simple Mathematical Model, T. I. Evans, Ralph E. White

Faculty Publications

A two-dimensional thermal model for spirally wound batteries has been developed. The governing equation of the model is the energy balance. Convective and insulated boundary conditions are used, and the equations are solved using a finite element code called TOPAZ2D. The finite element mesh is generated using a preprocessor to TOPAZ2D called MAZE. The model is used to estimate temperature profiles within a spirally wound D-size cell. The model is applied to the lithium/thionyl chloride cell because of the thermal management problems that this cell exhibits. Simplified one-dimensional models are presented that can be used to predict best and worst …


Book Review Of Selected Studies On Prophetic Interpretation, By William H. Shea, Richard M. Davidson Jan 1989

Book Review Of Selected Studies On Prophetic Interpretation, By William H. Shea, Richard M. Davidson

Faculty Publications

No abstract provided.


Tommaso Campanella's La Città Del Sole: Topography And Astrology, Ilona Klein Jan 1989

Tommaso Campanella's La Città Del Sole: Topography And Astrology, Ilona Klein

Faculty Publications

At the beginning of the seventeenth century the Dominican friar from Calabria, fra' Tommaso Campanella, had already solidified his anti-Aristotelian theories, had been persecuted and arrested, and was simulating madness in order to save his life while incarcerated in Naples. When Campanella conceived La Città del Sole under these circumstances in 1602, he was interpreting Telesio's naturalistic philosophy in a metaphysical manner, and was expressing in nuce the fundamental theories he would amplify two years later in Del Senso delle Cose e delle Magie.


Models And Tests In Functional Morphology: The Significance Of Description And Integration, Dominique G. Homberger Dec 1988

Models And Tests In Functional Morphology: The Significance Of Description And Integration, Dominique G. Homberger

Faculty Publications

SYNOPSIS: Functional-anatomical work on complex structural systems is handicapped by several difficulties: (1) Lack of established guidelines on how to select the structures that are relevant for the intended study, (2) lack of methods to check the accuracy of the description of a system's morphology, and (3) the need to integrate a large mass of results obtained through a variety of approaches taken from different disciplines, such as anatomy, physiology, physics, biochemistry, ecology and evolutionary biology. Suggestions to alleviate some of the problems include (1) to use information on the physiological and physical properties of the tissues in a system …


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 Oct 1988

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 …


Subspaces Of Lp,Q, N L. Carothers, S J. Dilworth Oct 1988

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.


A Parallel-Processing Subsystem For Rapid 3-D Interpolation Of Ct Images, William A. Barrett, Stephen J. Allan, Scott R. Cannon Sep 1988

A Parallel-Processing Subsystem For Rapid 3-D Interpolation Of Ct Images, William A. Barrett, Stephen J. Allan, Scott R. Cannon

Faculty Publications

An inexpensive parallel-processing subsystem for the rapid interpolation of CT image planes is demonstrated with a variety of node topologies. The subsystem is based on a tree network of INMOS T414 Transputer processors and is hosted by an AT-based image workstation. The subsystem accepts a stack of eight arbitrarily-spaced 256 x 256 image planes from the host. Subsystem output to the host consists of a stack of 32 scaled and evenly-spaced image planes (256 x 256 x 32 with cubic voxels). Benchmark execution times ranged from 12.3 seconds for three nodes to 5.8 seconds for eight nodes.


Dynamic Display And Quantitative Analysis Of Three-Dimensional Left Ventricular Pathology, William A. Barrett, Jayaram K. Udupa Sep 1988

Dynamic Display And Quantitative Analysis Of Three-Dimensional Left Ventricular Pathology, William A. Barrett, Jayaram K. Udupa

Faculty Publications

Techniques have been developed for automated extraction and dynamic interactive display of three-dimensional (3D) left ventricular (LV) surface anatomy from Cine CT images using a PC-based image display architecture. Images of both endocardial and myocardial surface anatomy are generated from multiple views at multiple time instances to demonstrate various LV pathologies including apical akinesis, apical and posterior aneurysms, LV Failure, IHSS, and a left atrial myxoma. Surface generation requires interpolation between scans, surface tracking, and rendering. Generation of 60 views corresponding to a single time instance requires approximately 15 minutes. LV dimensions are measured between two or more surface points …


Inequalities For Sums Of Independent Random Variables, N L. Carothers, S J. Dilworth Sep 1988

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.


Analysis Of The Convergence History Of Fluid Flow Through Nozzles With Shocks, Mohammad Saleem, A Cheer, M Hafez, T Pulliam Jul 1988

Analysis Of The Convergence History Of Fluid Flow Through Nozzles With Shocks, Mohammad Saleem, A Cheer, M Hafez, T Pulliam

Faculty Publications

"Convergence of iterative methods for the solution of the steady quasi-one-dimensional nozzle problem with shocks is considered. The finite-difference algorithms obtained from implicit schemes are used to approximate both the Euler and Navier-Stokes Equations. These algorithms are investigated for stability and convergence characteristics. The numerical methods are broken down into their matrix-vector components and then analyzed by examining a subset of the eigensystem using a method based on the Arnoldi process. The eigenvalues obtained by this method are accurate to within 5 digits for the largest ones and to within 2 digits for the ones smaller in magnitude compared the …


Successorship And The Duty To Bargain, B. Glenn George Jul 1988

Successorship And The Duty To Bargain, B. Glenn George

Faculty Publications

No abstract provided.


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 Jun 1988

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 …


Experimental Study Of Nonlinear Conductance In Small Metallic Samples, Richard A. Webb, S. Washburn, C. P. Umbach May 1988

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.


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 May 1988

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 …


Dissipative Quantum Tunneling: Quantum Langevin Equation Approach, G. W. Ford, J. T. Lewis, R. F. O'Connell Mar 1988

Dissipative Quantum Tunneling: Quantum Langevin Equation Approach, G. W. Ford, J. T. Lewis, R. F. O'Connell

Faculty Publications

The quantum Langevin equation is used as the basis for a discussion of dissipative quantum tunneling. A general analysis, including strong coupling and non-markovian (memory) effects, is given for the case of tunneling through a parabolic barrier at zero temperature in the presence of linear passive dissipation. It is shown that dissipation always decreases the tunneling rate below the barrier and increases transmission above the barrier. As a particular application, the case of the resistively shunted Josephson junction is considered. Simple closed form expressions for the tunneling rate and for the noise power spectrum are obtained and compared with results …


Present Net Worth And Internal Rate Of Return: A Note On Equivalence In Use, K. A. Blatner, Steven H. Bullard Jan 1988

Present Net Worth And Internal Rate Of Return: A Note On Equivalence In Use, K. A. Blatner, Steven H. Bullard

Faculty Publications

Present net worth and internal rate of return are frequently used for ranking investment alternatives. The relative merits and limitations of the two criteria are discussed at length in numerous journal articles and texts. For analysts wishing to present consistent project comparisons, the issue is not which criterion is superior, but when are they equivalent. In this article, conditions for equivalence in use are outlined under alternative assumptions. Although the conditions appear complex, they are not unduly restrictive.


Experiments With Disposable Hypodermic Syringes, Glen T. Clayton, Thomas O. Callaway, Harry D. Downing Jan 1988

Experiments With Disposable Hypodermic Syringes, Glen T. Clayton, Thomas O. Callaway, Harry D. Downing

Faculty Publications

No abstract provided.


The Admissibility Of Laboratory Reports In Criminal Trials: The Reliability Of Scientific Proof, Paul C. Giannelli Jan 1988

The Admissibility Of Laboratory Reports In Criminal Trials: The Reliability Of Scientific Proof, Paul C. Giannelli

Faculty Publications

No abstract provided.


Determination Of The Range In Binding-Site Densities Of Rat Skin Heparin Chains With High Binding Affinities For Antithrombin., A. A. Horner, M. Kusche, U. Lindahl, C. B. Peterson Jan 1988

Determination Of The Range In Binding-Site Densities Of Rat Skin Heparin Chains With High Binding Affinities For Antithrombin., A. A. Horner, M. Kusche, U. Lindahl, C. B. Peterson

Faculty Publications

Rat skin heparin proteoglycans vary markedly in the proportions of their constituent polysaccharide chains that have high binding affinity for antithrombin. As the proportion of such chains in a proteoglycan rises, their degree of affinity for antithrombin also increases [Horner (1987) Biochem. J. 244, 693-698]. The antithrombin-binding-site densities of such chains have now been determined, by measuring heparin-induced enhancement of the intrinsic fluorescence of antithrombin and by chemical analysis for the disaccharide sequence glucuronosyl-N-sulphoglucosaminyl (3,6-di-O-sulphate), which is unique to this site in heparin [Lindahl, Bäckström, Thunberg & Leder (1980) Proc. Natl. Acad. Sci. U.S.A. 77, 6551-6555]. Antithrombin-binding-site density ranged from …


Globally Hypoelliptic Systems Of Vector Fields On Nilmanifolds, Jacek M. Cygan, Leonard F. Richardson Jan 1988

Globally Hypoelliptic Systems Of Vector Fields On Nilmanifolds, Jacek M. Cygan, Leonard F. Richardson

Faculty Publications

We show that a system L of real vector fields on a general compact nilmanifold Γ{minus 45 degree rule};N induced by the Lie algebra N of N is globally hypoelliptic (GH) iff (1{ring operator}) The symbols of the vector fields of L projected onto the associated torus T = Γ[N, N]{minus 45 degree rule}N as functions on the integral lattice T ̂ collectively decrease at infinity not faster than a reciprocal of a polynomial and (2{ring operator}) the Lie subalgebra of N that L generates is not annihilated by any non-zero integral linear functional on any Nj Nj + 1, …


Comparison Between Solutions Of Sdes And Odes, P. Sundar Jan 1988

Comparison Between Solutions Of Sdes And Odes, P. Sundar

Faculty Publications

A ratio-limit comparison between ξt, the solution of an SDE driven by a semimartingale, and Ht, the solution of an associated ODE, is proved on the set where limt→∞ξt=∞. Sufficient conditions in terms of the driving processes and the coefficients are obtained for limt→∞ξt to be ∞. © 1988.


Integrated Semigroups And Their Applications To The Abstract Cauchy Problem, Frank Neubrander Jan 1988

Integrated Semigroups And Their Applications To The Abstract Cauchy Problem, Frank Neubrander

Faculty Publications

This paper is concerned with characterizations of those linear, closed, but not necessarily densely defined operators A on a Banach space E with nonempty resolvent set for which the abstract Cauchy problem u′(t) = Au(t), u(0) = x has unique, exponentially bounded solutions for every initial value x ∈ D(An). Investigating these operators we are led to the class of "integrated semigroups". Among others, this class contains the classes of strongly continuous semigroups and cosine families and the class of exponentially bounded distribution semigroups. The given characterizations of the generators of these integrated semigroups unify and generalize the classical characterizations …