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2004

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Introduction, Symposium Facing Climate Change: Opportunity And Tool For States, John C. Dernbach Dec 2003

Introduction, Symposium Facing Climate Change: Opportunity And Tool For States, John C. Dernbach

John C. Dernbach

No abstract provided.

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Simplification And Strengthening Of Weyl's Definition Of Asymptotic Equal Distribution Of Two Families Of Finite Sets, William F. Trench Dec 2003

Simplification And Strengthening Of Weyl's Definition Of Asymptotic Equal Distribution Of Two Families Of Finite Sets, William F. Trench

William F. Trench

No abstract provided.

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Analyzing Time-To-Event Data In A Clinical Trial When An Unknown Proportion Of Subjects Has Experienced The Event At Entry, Raji Balasubramanian, Stephen W. Lagakos Dec 2003

Analyzing Time-To-Event Data In A Clinical Trial When An Unknown Proportion Of Subjects Has Experienced The Event At Entry, Raji Balasubramanian, Stephen W. Lagakos

Raji Balasubramanian

In some clinical trials, where the outcome is the time until development of a silent event, an unknown proportion of subjects who have already experienced the event will be unknowingly enrolled due to the imperfect nature of the diagnostic tests used to screen potential subjects.F or example, commonly used diagnostic tests for evaluating HIV infection status in infants, such as DNA PCR and HIV Culture, have low sensitivity when given soon after infection.This can lead to the inclusion of an unknown proportion of HIV-infected infants into clinical trials aimed at the prevention of transmission from HIV-positive mothers to their infants …

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Science And Engineering Of Nanoparticle-Polymer Composites: Insights From Computer Simulation, Francis W. Starr, Sharon C. Glotzer Dec 2003

Science And Engineering Of Nanoparticle-Polymer Composites: Insights From Computer Simulation, Francis W. Starr, Sharon C. Glotzer

Francis Starr

No abstract provided.

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On Multivariate Abel-Gontscharoff Interpolation, Tian-Xiao He Dec 2003

On Multivariate Abel-Gontscharoff Interpolation, Tian-Xiao He

Tian-Xiao He

By using Gould's annihilation coefficients, we obtain an explicit fundamental polynomials of Multivariate Abel-Gontscharoff Interpolation and its remainder expression.

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Sadc Challenges Country Water Partnerships To Make Impact, Stanley Mubako Dec 2003

Sadc Challenges Country Water Partnerships To Make Impact, Stanley Mubako

Stanley Mubako

No abstract provided.

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Environment-Friendly Organic Synthesis Using Bismuth Compounds. Bismuth Triflate Catalyzed Synthesis Of Substituted 3,4-Dihydro-2h-L-Benzopyrans, Ram S. Mohan, Mai P. Nguyen, Joshua N. Arnold, Katherine E. Peterson Dec 2003

Environment-Friendly Organic Synthesis Using Bismuth Compounds. Bismuth Triflate Catalyzed Synthesis Of Substituted 3,4-Dihydro-2h-L-Benzopyrans, Ram S. Mohan, Mai P. Nguyen, Joshua N. Arnold, Katherine E. Peterson

Ram S. Mohan

A highly catalytic method for the synthesis of dihydrobenzopyrans from salicylaldehydes has been developed. An extension of this method to the synthesis of a pyrano [2,3,b]benzopyran has also been achieved. Bi(OTf)3.xH2O (1< x < 4) (0.1mol%) smoothly catalyzes the condensation of substituted salicylaldehydes with 2,2-dimethoxypropane to give the corresponding substituted 3,4-dihydro-2H-1-benzopyrans as a mixture of diastereomers (9:1) in moderate yields. The relative configuration of the methoxy groups in the two diastereomers was established by NOE experiments. The advantages of this method include the use of an easy to handle, inexpensive and relatively non-toxic catalyst.

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Bismuth Compounds In Organic Synthesis. Bismuth Nitrate Catalyzed Chemoselective Synthesis Of Acylals From Aromatic Aldehydes, Ram S. Mohan, David H. Aggen, Joshua N. Arnold, Patrick D. Hayes, Nathaniel J. Smoter Dec 2003

Bismuth Compounds In Organic Synthesis. Bismuth Nitrate Catalyzed Chemoselective Synthesis Of Acylals From Aromatic Aldehydes, Ram S. Mohan, David H. Aggen, Joshua N. Arnold, Patrick D. Hayes, Nathaniel J. Smoter

Ram S. Mohan

1Aromatic aldehydes are smoothly converted into the corresponding acylals in good yields in the presence of 3–10 mol% Bi(NO3)3•5H2O. Ketones are not affected under the reaction conditions. The relatively non-toxic nature of the catalyst, its ease of handling, easy availability and low cost make this procedure especially attractive for large-scale synthesis.

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Cortical Activation And Synchronization During Sentence Comprehension In High-Functioning Autism: Evidence Of Underconnectivity, Marcel Adam Just, Vladimir L. Cherkassky, Timothy A. Keller, Nancy J. Minshew Dec 2003

Cortical Activation And Synchronization During Sentence Comprehension In High-Functioning Autism: Evidence Of Underconnectivity, Marcel Adam Just, Vladimir L. Cherkassky, Timothy A. Keller, Nancy J. Minshew

Marcel Adam Just

No abstract provided.

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Spectral Densities Of Embedded Interfaces In Composite Materials, A. R. Mcgurn, Anthony Roy Day, D. J. Bergman, L. C. Davis, M. F. Thorpe Dec 2003

Spectral Densities Of Embedded Interfaces In Composite Materials, A. R. Mcgurn, Anthony Roy Day, D. J. Bergman, L. C. Davis, M. F. Thorpe

Anthony Roy Day

The effective resistivity and conductivity of two media that meet at a randomly rough interface are computed in the quasistatic limit. The results are presented in the spectral density representations of the Bergman-Milton formulation for the properties of two-component composite materials. The spectral densities are extracted from computer simulations of resistor networks in which the random interface separates two regions containing different types of resistors. In the limit that the bond lengths in the resistor network are small compared to parameters characterizing the surface roughness, the resistor network simulation approximates the continuum limit of the two-component composite. The Bergman-Milton formulation …

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Dynamic Heterogeneities In Supercooled Water, Nicolas Giovambattista, Marco Mazza, Sergey V. Buldyrev, Francis W. Starr, H. Eugene Stanley Dec 2003

Dynamic Heterogeneities In Supercooled Water, Nicolas Giovambattista, Marco Mazza, Sergey V. Buldyrev, Francis W. Starr, H. Eugene Stanley

Francis Starr

No abstract provided.

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Existence Of Solutions To A Hamiltonian System Without Convexity Condition On The Nonlinearity, Gregory S. Spradlin Dec 2003

Existence Of Solutions To A Hamiltonian System Without Convexity Condition On The Nonlinearity, Gregory S. Spradlin

Gregory S. Spradlin

We study a Hamiltonian system that has a superquadratic potential and is asymptotic to an autonomous system. In particular, we show the existence of a nontrivial solution homoclinic to zero. Many results of this type rely on a convexity condition on the nonlinearity, which makes the problem resemble in some sense the special case of homogeneous (power) nonlinearity. This paper replaces that condition with a different condition, which is automatically satisfied when the autonomous system is radially symmetric. Our proof employs variational and mountain-pass arguments. In some similar results requiring the convexity condition, solutions inhabit a submanifold homeomorphic to the …

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Swarm-Mediated Cluster-Based Construction, S. Kazadi, J. Wigglesworth, A. Grosz, A. Lim, D. Vitullo Dec 2003

Swarm-Mediated Cluster-Based Construction, S. Kazadi, J. Wigglesworth, A. Grosz, A. Lim, D. Vitullo

Sanza Kazadi

We investigate the use of swarm clustering algorithms in the design of simple robots capable of carrying out swarm-mediated construction. Methods for generating multiple clusters of predetermined size are developed. Relative cluster motion algorithms are also developed and explored. All robotic algorithms are predicated on the use of only robots utilizing no processing, gps, or explicit communication. Simple stigmergic communication and minimal sensing capabilities are used exclusively. We demonstrate swarms of minimal agents building equilateral triangles, squares, and pentagons. Future use of these methods in the design of more sophisticated construction techniques is discussed.

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Modelling Dynamic Conditional Correlations In Wti Oil Forward And Futures Returns, Alessandro Lanza, Matteo Manera, Micheal Mcaleer Dec 2003

Modelling Dynamic Conditional Correlations In Wti Oil Forward And Futures Returns, Alessandro Lanza, Matteo Manera, Micheal Mcaleer

Matteo Manera

This paper estimates the dynamic conditional correlations in the returns on WTI oil onemonth forward prices, and one-, three-, six-, and twelve-month futures prices, using recently developed multivariate conditional volatility models. The dynamic correlations enable a determination of whether the forward and various futures returns are substitutes or complements, which are crucial for deciding whether or not to hedge against unforeseen circumstances. The models are estimated using daily data on WTI oil forward and futures prices, and their associated returns, from 3 January 1985 to 16 January 2004. At the univariate level, the estimates are statistically significant, with the occasional …

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Using Dynamic Information In The Supply Network, Jeffrey Barker Dec 2003

Using Dynamic Information In The Supply Network, Jeffrey Barker

Jeffrey Barker

No abstract provided.

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An Inference Network Approach To Image Retrieval, Donald Metzler, R. Manmatha Dec 2003

An Inference Network Approach To Image Retrieval, Donald Metzler, R. Manmatha

R. Manmatha

Most image retrieval systems only allow a fragment of text or an example image as a query. Most users have more complex information needs that are not easily expressed in either of these forms. This paper proposes a model based on the Inference Network framework from information retrieval that employs a powerful query language that allows structured query operators, term weighting, and the combination of text and images within a query. The model uses non-parametric methods to estimate probabilities within the inference network. Image annotation and retrieval results are reported and compared against other published systems and illustrative structured and …

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Using Maximum Entropy For Automatic Image Annotation, Jiwoon Jeon, R. Manmatha Dec 2003

Using Maximum Entropy For Automatic Image Annotation, Jiwoon Jeon, R. Manmatha

R. Manmatha

In this paper, we propose the use of the Maximum Entropy approach for the task of automatic image annotation. Given labeled training data, Maximum Entropy is a statistical technique which allows one to predict the probability of a label given test data. The techniques allow for relationships between features to be effectively captured and has been successfully applied to a number of language tasks including machine translation. In our case, we view the image annotation task as one where a training data set of images labeled with keywords is provided and we need to automatically label the test images with …

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Vapor Pressures And Vaporization Enthalpies Of The N-Alkanes From C21 To C30 At T ) 298.15 K By Correlation Gas Chromatography, James S. Chickos, William Hanshaw Dec 2003

Vapor Pressures And Vaporization Enthalpies Of The N-Alkanes From C21 To C30 At T ) 298.15 K By Correlation Gas Chromatography, James S. Chickos, William Hanshaw

James Chickos

No abstract provided.

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Synthesis And Characterization Of A Novel 32-Membered Unsymmetrical Dinucleating [N12] Macrocycle: Preparation Of Bimetallic Complexes M2lx2(Clo4)2 (M = Zn, Cd Or Hg; X = Cl, Ncs Or No3), Z. A. Siddiqi Dr, Mohammad Mansoob Khan Dr Dec 2003

Synthesis And Characterization Of A Novel 32-Membered Unsymmetrical Dinucleating [N12] Macrocycle: Preparation Of Bimetallic Complexes M2lx2(Clo4)2 (M = Zn, Cd Or Hg; X = Cl, Ncs Or No3), Z. A. Siddiqi Dr, Mohammad Mansoob Khan Dr

Dr. Mohammad Mansoob Khan

The condensation reaction of N-acetylaniline with 1,3-diaminopropane in 2 : 1 mole ratio under reflux condition generates an intermediate species having C55N bonds. The in situ reaction of the intermediate with HCHO and 1,3-diaminopropane in the presence of perchloric acid results in an off-white solid product. Analytical, FAB mass, IR, 1H NMR and electronic spectral data of this solid are consistent with the formation of the dihydroperchlorate salt of an unsymmetrical 32-membered [N12] macrocycle [L.2HClO4] via a capping mechanism of the intermediate species. Reactions of [L 2HClO4] with Group 12 metal salts, MX2, and their precursors, [M(Ph3P)2Cl2], produce bimetallic complexes …

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Ensuring The Comparability Of Comparison Groups: Is Randomization Enough?, Vance Berger, Sherri Rose Dec 2003

Ensuring The Comparability Of Comparison Groups: Is Randomization Enough?, Vance Berger, Sherri Rose

Sherri Rose

It is widely believed that baseline imbalances in randomized trials must necessarily be random. In fact, there is a type of selection bias that can cause substantial, systematic and reproducible baseline imbalances of prognostic covariates even in properly randomized trials. It is possible, given complete data, to quantify both the susceptibility of a given trial to this type of selection bias and the extent to which selection bias appears to have caused either observable or unobservable baseline imbalances. Yet, in articles reporting on randomized trials, it is uncommon to find either these assessments or the information that would enable a …

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Making Sustainable Development Happen: From Johannesburg To Albany, John C. Dernbach Dec 2003

Making Sustainable Development Happen: From Johannesburg To Albany, John C. Dernbach

John C. Dernbach

No abstract provided.

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Fall Prevention Programs For The Elderly: A Bayesian Secondary Meta-Analysis, Joseph F. Lucke Dec 2003

Fall Prevention Programs For The Elderly: A Bayesian Secondary Meta-Analysis, Joseph F. Lucke

Joseph Lucke

A secondary meta-analysis of programs to reduce falls in the elderly is undertaken to demonstrate a Bayesian analysis. The Bayesian statistical tradition is carefully distinguished from the standard Neyman-Pearson-Wald (NPW) statistical tradition. In the 12 studies, the logit effect size is used to compare treatment groups using a prevention program to control groups without a program. To contrast the Bayesian analysis, independent-effects and fixed-effect meta-analyses are first conducted in the NPW tradition. This is followed by Bayesian independent-effects and fixed-effect meta-analyses that numerically replicate the NPW results but have conceptually different interpretations. The final analyses comprise Bayesian random-effects and predictive …

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