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A Community Of Interest In The Due Process Calculus, Charles H. Koch Jr. Oct 2000

A Community Of Interest In The Due Process Calculus, Charles H. Koch Jr.

Faculty Publications

No abstract provided.

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High Phosphorylation Efficiency And Depression Of Uncoupled Respiration In Mitochondria Under Hypoxia, Erich Gnaiger, Gabriela Méndez, Steven C. Hand Sep 2000

High Phosphorylation Efficiency And Depression Of Uncoupled Respiration In Mitochondria Under Hypoxia, Erich Gnaiger, Gabriela Méndez, Steven C. Hand

Faculty Publications

Mitochondria are confronted with low oxygen levels in the microenvironment within tissues; yet, isolated mitochondria are routinely studied under air-saturated conditions that are effectively hyperoxic, increase oxidative stress, and may impair mitochondrial function. Under hypoxia, on the other hand, respiration and ATP supply are restricted. Under these conditions of oxygen limitation, any compromise in the coupling of oxidative phosphorylation to oxygen consumption could accentuate ATP depletion, leading to metabolic failure. To address this issue, we have developed the approach of oxygen-injection microcalorimetry and ADP-injection respirometry for evaluating mitochondrial function at limiting oxygen supply. Whereas phosphorylation efficiency drops during ADP limitation …

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Optically Simulating A Quantum Associative Memory, Dan A. Ventura, John C. Howell, John A. Yeazell Sep 2000

Optically Simulating A Quantum Associative Memory, Dan A. Ventura, John C. Howell, John A. Yeazell

Faculty Publications

This paper discusses the realization of a quantum associative memory using linear integrated optics. An associative memory produces a full pattern of bits when presented with only a partial pattern. Quantum computers have the potential to store large numbers of patterns and hence have the ability to far surpass any classical neural network realization of an associative memory. In this work two 3-qubit associative memories will be discussed using linear integrated optics. In addition, corrupted, invented and degenerate memories are discussed.

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Effect Of Collagen Turnover On The Accumulation Of Advanced Glycation End Products, Nicole Verzijl, Jeroen Degroot, Suzanne R. Thorpe, Ruud A. Bank, J. Nikki Shaw, Timothy J. Lyons, Johannes Wj Bijlsma, Floris Pjg Lafeber, John W. Baynes, Johan M. Tekoppele Sep 2000

Effect Of Collagen Turnover On The Accumulation Of Advanced Glycation End Products, Nicole Verzijl, Jeroen Degroot, Suzanne R. Thorpe, Ruud A. Bank, J. Nikki Shaw, Timothy J. Lyons, Johannes Wj Bijlsma, Floris Pjg Lafeber, John W. Baynes, Johan M. Tekoppele

Faculty Publications

Collagen molecules in articular cartilage have an exceptionally long lifetime, which makes them susceptible to the accumulation of advanced glycation end products (AGEs). In fact, in comparison to other collagen-rich tissues, articular cartilage contains relatively high amounts of the AGE pentosidine. To test the hypothesis that this higher AGE accumulation is primarily the result of the slow turnover of cartilage collagen, AGE levels in cartilage and skin collagen were compared with the degree of racemization of aspartic acid (% D-Asp, a measure of the residence time of a protein). AGE (Ne- (carboxymethyl)lysine, Ne-(carboxyethyl)lysine, and pentosidine) and % D-Asp concentrations increased …

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Re: 'Differences In Socioeconomic Status And Survival Among White And Black Men With Prostate Cancer' [1] (Multiple Letters), Jay S. Kaufman, Robert Millikan, Charles Poole, Paul Godley, Richard S. Cooper, Vincent Freeman Sep 2000

Re: 'Differences In Socioeconomic Status And Survival Among White And Black Men With Prostate Cancer' [1] (Multiple Letters), Jay S. Kaufman, Robert Millikan, Charles Poole, Paul Godley, Richard S. Cooper, Vincent Freeman

Faculty Publications

No abstract provided.

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Regulation Of Sup Expression Identifies Multiple Regulators Involved In Arabidopsis Floral Meristem Development, Hajime Sakai, Beth A. Krizek, Steven E. Jacobsen, Elliot M. Meyerowitz Sep 2000

Regulation Of Sup Expression Identifies Multiple Regulators Involved In Arabidopsis Floral Meristem Development, Hajime Sakai, Beth A. Krizek, Steven E. Jacobsen, Elliot M. Meyerowitz

Faculty Publications

During the course of flower development, floral homeotic genes are expressed in defined concentric regions of floral meristems called whorls. The SUPERMAN ( SUP, also called FLO10 ) gene, which encodes a C2H2-type zinc finger protein, is involved in maintenance of the stamen/carpel whorl boundary (the boundary between whorl 3 and whorl 4) in Arabidopsis. Here, we show that the regulation of SUP expression in floral meristems is complex, consisting of two distinct phases, initiation and maintenance. The floral meristem identity gene LEAFY ( LFY ) plays a role in the initiation phase through at least two pathways, which …

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On The Assignment Of Gender To Chicano Anglicisms: Processes And Results, Robert N. Smead Sep 2000

On The Assignment Of Gender To Chicano Anglicisms: Processes And Results, Robert N. Smead

Faculty Publications

The creation of neologisms through linguistic borrowing is a complex process. For donor language models to be transformed into host language replicas, phonological and morphological adaptation must take place. Part and parcel of that adaptation is the assignment of gender to loanwords in a host language like Spanish. The present article examines gender assignment in two corpora of loanwords (New Mexican and Southern Colorado Spanish: N=212 and General Chicano Spanish: N=595). Through the application of variable rule methodology (GoldVarb 2), five factors are posited as significant. Two of these categorically determine gender assignment when present: (1) the biological sex of …

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Using Hydrothermal Time Concepts To Model Seed Germination Response To Temperature Dormancy Loss And Priming Effects In Elymus Elymoides, Phil S. Allen, Susan E. Meyer, Susan B. Debaene-Gill Sep 2000

Using Hydrothermal Time Concepts To Model Seed Germination Response To Temperature Dormancy Loss And Priming Effects In Elymus Elymoides, Phil S. Allen, Susan E. Meyer, Susan B. Debaene-Gill

Faculty Publications

Hydrothermal time (HTT) describes progress toward seed germination under various combinations of incubation water potential (Ψ) and temperature (T). To examine changes in HTT parameters during dormancy loss, seeds from two populations of the bunchgrass Elymus elymoides were incubated under seven temperature regimes following dry storage at 10, 20 and 30 °C for intervals from 0 to 16 weeks. Fully after-ripened seeds were primed for 1 week at a range of s. Data on germination rate during priming were used to obtain a HTT equation for each seed population, while data obtained following transfer to water were used to calculate …

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A Dynamic Optimal Trajectory Generator For Cartesian Path Following, Edward Red Sep 2000

A Dynamic Optimal Trajectory Generator For Cartesian Path Following, Edward Red

Faculty Publications

This paper considers a dynamic and adaptive trajectory generator for negotiating paths using S-curves. Applying constant jerk transitions between the constant acceleration and deceleration periods of the trajectory, the trajectory will optimally transition to the desired speed setting. Optimal is defined to be the minimum time to transition from the current speed to the set speed for the move segment when jerk and acceleration are limited. The S-curve equations will adapt to instantaneous changes in speed setting and path length. An integrated motion planner will determine allowable speeds and transitional profiles based on the remaining move distance.

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Peaches, Speech, And Clarence Thomas: Yes, California, There Is A Justice Who Understands The Ramifications Of Controlling Commercial Speech, Jennifer R. Franklin Sep 2000

Peaches, Speech, And Clarence Thomas: Yes, California, There Is A Justice Who Understands The Ramifications Of Controlling Commercial Speech, Jennifer R. Franklin

Faculty Publications

No abstract provided.

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The Supreme Court's Backwards Proportionaility Jurisprudence: Comparing Judicial Review Of Excessive Criminal Punishments And Excessive Punitive Damages Award, Adam M. Gershowitz Sep 2000

The Supreme Court's Backwards Proportionaility Jurisprudence: Comparing Judicial Review Of Excessive Criminal Punishments And Excessive Punitive Damages Award, Adam M. Gershowitz

Faculty Publications

No abstract provided.

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The Polarization Of Sb Overlayers On Nimnsb(100), Takashi Komesu, C. N. Borca, Hae Kyung Jeong, P. A. Dowben, Delia Ristoiu, J. P. Nozières, Shane Stadler, Y. U. Idzerda Aug 2000

The Polarization Of Sb Overlayers On Nimnsb(100), Takashi Komesu, C. N. Borca, Hae Kyung Jeong, P. A. Dowben, Delia Ristoiu, J. P. Nozières, Shane Stadler, Y. U. Idzerda

Faculty Publications

We have investigated the induced polarization of paramagnetic Sb overlayers on the Heusler alloy NiMnSb. From combined X-ray absorption spectroscopy (XAS) and spin-polarized inverse photoemission spectroscopy (SPIPES), we can assign some of the unoccupied states of the Heusler alloy NiMnSb. With increasing thickness of the Sb overlayer, there is a decline in the density of states near the Fermi energy, as expected for a semimetal overlayer on a metallic substrate. While the Sb is polarized by the ferromagnetic NiMnSb substrate, consistent with the expectations of mean field theory, the polarization at the center of the surface/overlayer Brillouin zone cannot be …

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Canonical Quantum Gravity In The Vassiliev Invariants Arena: I. Kinematical Structure, Cayetano Di Bartolo, Rodolfo Gambini, Jorge Griego, Jorge Pullin Aug 2000

Canonical Quantum Gravity In The Vassiliev Invariants Arena: I. Kinematical Structure, Cayetano Di Bartolo, Rodolfo Gambini, Jorge Griego, Jorge Pullin

Faculty Publications

We generalize the idea of Vassiliev invariants to the spin network context, with the aim of using these invariants as a kinematical arena for a canonical quantization of gravity. This paper presents a detailed construction of these invariants (both ambient and regular isotopic) requiring a significant elaboration based on the use of Chern - Simons perturbation theory which extends the work of Kauffman, Martin and Witten to four-valent networks. We show that this space of knot invariants has the crucial property - from the point of view of the quantization of gravity - of being loop differentiable in the sense …

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Canonical Quantum Gravity In The Vassiliev Invariants Arena: Ii. Constraints, Habitats And Consistency Of The Constraint Algebra, Cayetano Di Bartolo, Rodolfo Gambini, Jorge Griego, Jorge Pullin Aug 2000

Canonical Quantum Gravity In The Vassiliev Invariants Arena: Ii. Constraints, Habitats And Consistency Of The Constraint Algebra, Cayetano Di Bartolo, Rodolfo Gambini, Jorge Griego, Jorge Pullin

Faculty Publications

In a companion paper we introduced a kinematical arena for the discussion of the constraints of canonical quantum gravity in the spin network representation based on Vassiliev invariants. In this paper we introduce the Hamiltonian constraint, extend the space of states to non-diffeomorphism-invariant 'habitats' and check that the off-shell quantum constraint commutator algebra reproduces the classical Poisson algebra of constraints of general relativity without anomalies. One can therefore consider the resulting set of constraints and space of states as a consistent theory of canonical quantum gravity.

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Measurement Of Exclusive Ω Electroproduction At Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti Aug 2000

Measurement Of Exclusive Ω Electroproduction At Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti

Faculty Publications

The exclusive electroproduction of ω mesons, ep → e ω p, has been studied in the kinematic range 3 < Q2 < 20 GeV2, 40 < W < 120 GeV and |t| < 0.6 GeV2 with the ZEUS detector at HERA using an integrated luminosity of 37.7 pb-1. The ω mesons were identified via the decay ω → π+ π- π0. The exclusive cross section in the above kinematic region is σ(ep) → e ω p = 0.108 ± 0.014 (stat.) ± 0.026(syst.) nb. The reaction ep → e φ p, φ → π+ π- π0, has also been measured. The cross sections, as well as the ratios σ γ·p → ωp/σ γ · p → p0p and σ γ · p → ωp/σγ·p → φp, are presented as a function of W and Q2. Thus, for the first time, the properties of ω electroproduction can be compared to those of p0,φ and J/ψ electroproduction at high W. (C) 2000 Elsevier Science B.V.

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The X-Ray Transient Xte J1118+480: Multiwavelength Observations Of A Low-State Minioutburst, R. I. Hynes, C. W. Mauche, C. A. Haswell, C. R. Shrader, W. Cui, S. Chaty Aug 2000

The X-Ray Transient Xte J1118+480: Multiwavelength Observations Of A Low-State Minioutburst, R. I. Hynes, C. W. Mauche, C. A. Haswell, C. R. Shrader, W. Cui, S. Chaty

Faculty Publications

We present multiwavelength observations of the newly discovered X-ray transient XTE J1118+480 obtained in the rising phase of the 2000 April outburst. This source is located at unusually high Galactic latitude and in a very low absorption line of sight. This made the first Extreme Ultraviolet Explorer (EUVE) spectroscopy of an X-ray transient outburst possible. Together with our Hubble Space Telescope, Rossi X-Ray Timing Explorer, and United Kingdom Infrared Telescope data, this gives unprecedented spectral coverage. We find the source in the low hard state. The flat IR-UV continuum appears to be a combination of optically thick disk emission and …

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Measurement Of The Proton Structure Function F2 At Very Low Q2 At Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi Aug 2000

Measurement Of The Proton Structure Function F2 At Very Low Q2 At Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi

Faculty Publications

A measurement of the proton structure function F2(x, Q2) is presented in the kinematic range 0.045 GeV2 < Q2 < 0.65 GeV2 and 6 · 10-7 < x < 1 · 10-3. The results were obtained using a data sample corresponding to an integrated luminosity of 3.9pb-1 in e+ p reactions recorded with the ZEUS detector at HERA. Information from a silicon-strip tracking detector, installed in front of the small electromagnetic calorimeter used to measure the energy of the final-state positron at small scattering angles, together with an enhanced simulation of the hadronic final state, has permitted the extension of the kinematic range beyond that of previous measurements. The uncertainties in F2 are typically less than 4%. At the low Q2 values of the present measurement, the rise of F2 at low x is slower than observed in HERA data at higher Q2 and can be described by Regge theory with a constant logarithmic slope δlnF2/δln(1/x). The dependence of F2 on Q2 is stronger than at higher Q2 values, approaching, at the lowest Q2 values of this measurement, a region where F2 becomes nearly proportional to Q2. (C) 2000 Elsevier Science B.V.

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An Approximation To Miscible Fluid Flows In Porous Media With Point Sources And Sinks By An Eulerian-Lagrangian Localized Adjoint Method And Mixed Finite Element Methods, Hong Wang, Liang Dong, Richard E. Ewing, Stephen L. Lyons, Guan Qin Aug 2000

An Approximation To Miscible Fluid Flows In Porous Media With Point Sources And Sinks By An Eulerian-Lagrangian Localized Adjoint Method And Mixed Finite Element Methods, Hong Wang, Liang Dong, Richard E. Ewing, Stephen L. Lyons, Guan Qin

Faculty Publications

We develop an Eulerian–Lagrangian localized adjoint method (ELLAM)-mixed finite element method (MFEM) solution technique for accurate numerical simulation of coupled systems of partial differential equations (PDEs), which describe complex fluid flow processes in porous media. An ELLAM, which was shown previously to outperform many widely used methods in the context of linear convection-diffusion PDEs, is presented to solve the transport equation for concentration. Since accurate fluid velocities are crucial in numerical simulations, an MFEM is used to solve the pressure equation for the pressure and Darcy velocity. This minimizes the numerical difficulties occurring in standard methods for approximating velocities caused …

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Synchrotron X-Ray Microtomography, Electron Probe Microanalysis, And Nmr Of Toluene Waste In Cement, Leslie G. Butler, John W. Owens, Frank K. Cartledge, Richard L. Kurtz, Gary R. Byerly, Andrew J. Wales, Pamela L. Bryant, Earl F. Emery, Betsy Dowd, Xiaogang Xie Aug 2000

Synchrotron X-Ray Microtomography, Electron Probe Microanalysis, And Nmr Of Toluene Waste In Cement, Leslie G. Butler, John W. Owens, Frank K. Cartledge, Richard L. Kurtz, Gary R. Byerly, Andrew J. Wales, Pamela L. Bryant, Earl F. Emery, Betsy Dowd, Xiaogang Xie

Faculty Publications

Synchrotron X-ray microtomography shows vesicular structures for toluene/cement mixtures, prepared with 1.22-3.58 wt % toluene. Three-dimensional imaging of the cured samples shows spherical vesicles, with diameters ranging from 20 to 250/μm; a search with EPMA for vesicles in the range of 1-20/μm proved negative. However, the total vesicle volume, as computed from the microtomography images, accounts for less than 10% of initial toluene. Since the cements were cured in sealed bottles, the larger portion of toluene must be dispersed within the cement matrix. Evidence for toluene in the cement matrix comes from 29Si MAS NMR spectroscopy, which shows a reduction …

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A Library ‘Teens’Cape’ Against The New Callousness, Anthony Bernier Aug 2000

A Library ‘Teens’Cape’ Against The New Callousness, Anthony Bernier

Faculty Publications

No abstract provided.

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Flux Of Nutrients From Russian Rivers To The Arctic Ocean: Can We Establish A Baseline Against Which To Judge Future Changes?, R. M. Holmes, B. J. Peterson, V. V. Gordeev, A. V. Zhulidov, M. Meybeck, Richard B. Lammers, Charles J. Vorosmarty Aug 2000

Flux Of Nutrients From Russian Rivers To The Arctic Ocean: Can We Establish A Baseline Against Which To Judge Future Changes?, R. M. Holmes, B. J. Peterson, V. V. Gordeev, A. V. Zhulidov, M. Meybeck, Richard B. Lammers, Charles J. Vorosmarty

Faculty Publications

Climate models predict significant warming in the Arctic in the 21st century, which will impact the functioning of terrestrial and aquatic ecosystems as well as alter land‐ocean interactions in the Arctic. Because river discharge and nutrient flux integrate large‐scale processes, they should be sensitive indicators of change, but detection of future changes requires knowledge of current conditions. Our objective in this paper is to evaluate the current state of affairs with respect to estimating nutrient flux to the Arctic Ocean from Russian rivers. To this end we provide estimates of contemporary (1970s–1990s) nitrate, ammonium, and phosphate fluxes to the Arctic …

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Masses For Galactic Beat Cepheids, Noella L. D'Cruz, Siobahn M. Morgan, Erika Böhm-Vitense Aug 2000

Masses For Galactic Beat Cepheids, Noella L. D'Cruz, Siobahn M. Morgan, Erika Böhm-Vitense

Faculty Publications

Accurate mass determinations for Cepheids may be used to determine the degree of excess mixing in the interiors of their main-sequence progenitors : the larger the excess mixing, the larger the luminosity of the Cepheid of a given mass, or the smaller the mass of a Cepheid with given luminosity. Dynamical masses determined recently for a few Cepheid binaries indicate excess mixing somewhat stronger than that corresponding to the convective overshoot models by Schaller et al. Beat Cepheids can be used similarly to test main-sequence mixing in stellar interiors. The period ratios for beat Cepheids depend on luminosity, heavy element …

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Children's Understanding Of The Concept Of Physical Activity, Stewart G. Trost, Angela M. Morgan, Ruth P. Saunders, Gwen A. Felton, Dianne S. Ward, Russell R. Pate Aug 2000

Children's Understanding Of The Concept Of Physical Activity, Stewart G. Trost, Angela M. Morgan, Ruth P. Saunders, Gwen A. Felton, Dianne S. Ward, Russell R. Pate

Faculty Publications

This study evaluated 4th-grade students' understanding of the concept of physical activity and assessed the effects of two interventions to enhance the students' understanding of this concept. Students were randomly assigned to 1 of 3 conditions: the video group (n=40) watched a 5-min video describing physical activity; the verbal group (n=42) listened to a generic description of physical activity; the control group received no instruction (n=45). Students completed a 17-item checklist testing their understanding of the concept of physical activity. Compared to controls, students in the verbal and video group demonstrated significantly higher checklist …

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The Inefficiency Of Batch Training For Large Training Sets, Tony R. Martinez, D. Randall Wilson Jul 2000

The Inefficiency Of Batch Training For Large Training Sets, Tony R. Martinez, D. Randall Wilson

Faculty Publications

Multilayer perceptrons are often trained using error backpropagation (BP). BP training can be done in either a batch or continuous manner. Claims have frequently been made that batch training is faster and/or more "correct" than continuous training because it uses a better approximation of the true gradient for its weight updates. These claims are often supported by empirical evidence on very small data sets. These claims are untrue, however, for large training sets. This paper explains why batch training is much slower than continuous training for large training sets. Various levels of semi-batch training used on a 20,000-instance speech recognition …

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Optical Studies Of The X-Ray Transient Xte J2123-058 - I. Photometry, C. Zurita, J. Casares, T. Shahbaz, P. A. Charles, R. I. Hynes, S. Shugarov, V. Goransky, E. P. Pavlenko, Y. Kuznetsova Jul 2000

Optical Studies Of The X-Ray Transient Xte J2123-058 - I. Photometry, C. Zurita, J. Casares, T. Shahbaz, P. A. Charles, R. I. Hynes, S. Shugarov, V. Goransky, E. P. Pavlenko, Y. Kuznetsova

Faculty Publications

We present optical photometry of the X-ray transient XTE J2123-058, obtained in 1998 July-October. The light curves are strongly modulated on the 5.95-h orbital period, and exhibit dramatic changes in amplitude and form during the decline. We used synthetic models, which include the effect of partial eclipses and X-ray heating effects, to estimate the system parameters, and we constrain the binary inclination to be i = 73° ± 4. The model is successful in reproducing the light curves at different stages of the decay by requiring the accretion disc to become smaller and thinner by 30 per cent as the …

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Pyridoxamine, An Inhibitor Of Advanced Glycation Reactions, Also Inhibits Advanced Lipoxidation Reactions: Mechanism Of Action Of Pyridoxamine, Joelle M. Onorato, Alicia J. Jenkins, Suzanne R. Thorpe, John W. Baynes Jul 2000

Pyridoxamine, An Inhibitor Of Advanced Glycation Reactions, Also Inhibits Advanced Lipoxidation Reactions: Mechanism Of Action Of Pyridoxamine, Joelle M. Onorato, Alicia J. Jenkins, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

Maillard or browning reactions lead to formation of advanced glycation end products (AGEs) on protein and contribute to the increase in chemical modification of proteins during aging and in diabetes. AGE inhibitors such as aminoguanidine and pyridoxamine (PM) have proven effective in animal model and clinical studies as inhibitors of AGE formation and development of diabetic complications. We report here that PM also inhibits the chemical modification of proteins during lipid peroxidation (lipoxidation) reactions in vitro, and we show that it traps reactive intermediates formed during lipid peroxidation. In reactions of arachidonate with the model protein RNase, PM prevented modification …

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Plasma Oscillations And Expansion Of An Ultracold Neutral Plasma, Scott D. Bergeson, S. Kulin, T. C. Killian, S. L. Rolston Jul 2000

Plasma Oscillations And Expansion Of An Ultracold Neutral Plasma, Scott D. Bergeson, S. Kulin, T. C. Killian, S. L. Rolston

Faculty Publications

We report the observation of plasma oscillations in an ultracold neutral plasma. With this collective mode we probe the electron density distribution and study the expansion of the plasma as a function of time. For classical plasma conditions, i.e., weak Coulomb coupling, the expansion is dominated by the pressure of the electron gas and is described by a hydrodynamic model. Discrepancies between the model and observations at low temperature and high density may be due to strong coupling of the electrons.

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Differentiating The Free Exercise And Establishment Clauses, Carl H. Esbeck Jul 2000

Differentiating The Free Exercise And Establishment Clauses, Carl H. Esbeck

Faculty Publications

The purpose of the Establishment Clause is not to safeguard individual religious rights. That is the role of the Free Exercise Clause, indeed its singular role. The purpose of the Establishment Clause, rather, is as a structural restraint on governmental power. Because of its structural character, the task of the Establishment Clause is to limit government from legislating or otherwise acting on any matter "respecting an establishment of religion." The powers that fall within the scope of the foregoing clause (denied to government, hence within the sole province of religion) and the powers outside this clause (hence, authority vested in …

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Theoretical Studies Of The Reactivity Of Cyclopentadienyl Nitrosyl Alkyl Species Of Molybdenum And Tungsten, Rinaldo Poli, Kevin M. Smith Jul 2000

Theoretical Studies Of The Reactivity Of Cyclopentadienyl Nitrosyl Alkyl Species Of Molybdenum And Tungsten, Rinaldo Poli, Kevin M. Smith

Faculty Publications

The reactivity differences observed experimentally for Cp*W(NO)(CH2CMe3)2 and CpMo(NO)(CH2CMe3)2 have been investigated using density functional theory (DFT) techniques. The reactions of the CpW(NO)(CH2) model complex with NH3 and CH4 are more exothermic and have lower activation barriers than the corresponding processes for CpMo(NO)(CH2). The η2(C,H) methane complex CpM(NO)(CH2)(CH4) (M = Mo, W) can undergo two competitive processes: C-H activation to afford CpM(NO)(CH3)2 or loss of methane. The relative barrier heights are almost identical for M = W, whereas the formation of CpM(NO)(CH3)2 is significantly disfavored for M = Mo. The activation of C-H and N-H bonds proceeds via a direct, …

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An Iterative Approach To Multisensor Sea Ice Classification, David G. Long, Mark R. Drinkwater, Quinn P. Remund Jul 2000

An Iterative Approach To Multisensor Sea Ice Classification, David G. Long, Mark R. Drinkwater, Quinn P. Remund

Faculty Publications

Characterizing the variability in sea ice in the polar regions is fundamental to an understanding of global climate and the geophysical processes governing climate changes. Sea ice can be grouped into a number of general classes with different characteristics. Multisensor data from NSCAT, ERS-2, and SSM/I are reconstructed into enhanced resolution imagery for use in ice-type classification. The resulting twelve-dimensional data set is linearly transformed through principal component analysis to reduce data dimensionality and noise levels. An iterative statistical data segmentation algorithm is developed using maximum likelihood (ML) and maximum a posteriori (MAP) techniques. For a given ice type, the …

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