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2006

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Investigating Mediation When Counterfactuals Are Not Metaphysical: Does Sunlight Uvb Exposure Mediate The Effect Of Eyeglasses On Cataracts?, Brian Egleston, Daniel O. Scharfstein, Beatriz Munoz, Sheila West Jul 2006

Investigating Mediation When Counterfactuals Are Not Metaphysical: Does Sunlight Uvb Exposure Mediate The Effect Of Eyeglasses On Cataracts?, Brian Egleston, Daniel O. Scharfstein, Beatriz Munoz, Sheila West

Johns Hopkins University, Dept. of Biostatistics Working Papers

We investigate the degree to which a reduction in ocular sunlight ultra-violet B (UVB) exposure mediates a relationship between wearing eyeglasses and a decreased risk of cataracts. An estimand is proposed in which causal effects are estimated locally within strata based on potential UVB exposure without glasses and the degree to which glasses use reduces UVB exposure. We take advantage of the structure of the data in which the counterfactual UVB exposures if the participants in the study who wore glasses had not worn glasses are considered observable.

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Description Of Spherical Aberration And Coma Of A Microlens Using Vector Diffraction Theory, Glen D. Gillen, Shekhar Guha Jul 2006

Description Of Spherical Aberration And Coma Of A Microlens Using Vector Diffraction Theory, Glen D. Gillen, Shekhar Guha

Physics

Light distributions of a plane wave refracted by a microlens are calculated using Kirchhoff vector diffraction theory. Numerical results for one and two-dimensional beam profiles and the onset and effects of spherical aberration and coma are investigated for different lens parameters.

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Understanding Brigham Young University's Technology Teacher Education Program's Sucess In Attracting And Retaining Female Students, Katrina M. Cox Jul 2006

Understanding Brigham Young University's Technology Teacher Education Program's Sucess In Attracting And Retaining Female Students, Katrina M. Cox

Theses and Dissertations

The purpose of the study was to attempt to understand why Brigham Young University Technology Teacher Education program has attracted and retained a high number of females. This was done through a self-created survey composed of four forced responses, distributed among the Winter 2006 semester students. Likert-scale questions were outlined according to the five theoretical influences on women in technology, as established by Welty and Puck (2001) and two of the three relationships of academia, as established by Haynie III (1999), as well as three free response questions regarding retention and attraction within the major. Findings suggested strong positive polarity …

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Topics On The Spectral Theory Of Automorphic Forms, Dustin David Belt Jul 2006

Topics On The Spectral Theory Of Automorphic Forms, Dustin David Belt

Theses and Dissertations

We study the analytic properties of the Eisenstein Series of $frac {1}{2}$-integral weight associated with the Hecke congruence subgroup $Gamma_0(4)$. Using these properties we obtain asymptotics for sums of certain Dirichlet $L$-series. We also obtain a formula reducing the study of Selberg's Eigenvalue Conjecture to the study of the nonvanishing of the Eisenstein Series $E(z,s)$ for Hecke congruence subgroups $Gamma_0(N)$ at $s=frac {1+i}{2}$.

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Reading And Writing In Science: How Do The Reform Documents Attend To The Fundamental Sense Of Science Literacy?, Kimberly J. Frandsen Jul 2006

Reading And Writing In Science: How Do The Reform Documents Attend To The Fundamental Sense Of Science Literacy?, Kimberly J. Frandsen

Theses and Dissertations

The purpose of this study was to examine and describe fundamental literacy messages found within three major science reform documents: Science for all Americans: Project 2061 (AAAS, 1990), Benchmarks for Science Literacy (AAAS, 1993), and the National Science Education Standards (NRC, 1996). A qualitative content analysis was performed in an effort to reveal any messages or statements supporting fundamental science literacy. Results from this study indicate that key science reform documents do in fact contain multiple messages supporting the fundamental sense of science literacy, however, the nature of these messages, the quantity, placement and presence of negative literacy statements may …

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Anguilliform Larvae Collected Off North Carolina, Steve W. Ross, Tara L. Casazza, Andrea M. Quattrini, Kenneth J. Sulak Jul 2006

Anguilliform Larvae Collected Off North Carolina, Steve W. Ross, Tara L. Casazza, Andrea M. Quattrini, Kenneth J. Sulak

United States Geological Survey: Staff Publications

The distinctive larval stage of eels (leptocephalus) facilitates dispersal through prolonged life in the open ocean. Leptocephali are abundant and diverse off North Carolina, yet data on distributions and biology are lacking. The water column (from surface to 1,293 m) was sampled in or near the Gulf Stream off Cape Hatteras, Cape Lookout, and Cape Fear, North Carolina during summer through fall of 1999–2005, and leptocephali were collected by neuston net, plankton net, Tucker trawl, and dip net. Additional samples were collected nearly monthly from a transect across southern Onslow Bay, North Carolina (from surface to 91 m) from April …

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Search For A Heavy Resonance Decaying Into A Z+ Jet Final State In Pp̅ Collisions At √S =1:96 Tev Using The D0 Detector, V. M. Abazov, Kenneth A. Bloom, Gregory R. Snow, D0 Collaboration Jul 2006

Search For A Heavy Resonance Decaying Into A Z+ Jet Final State In Pp̅ Collisions At √S =1:96 Tev Using The D0 Detector, V. M. Abazov, Kenneth A. Bloom, Gregory R. Snow, D0 Collaboration

Kenneth Bloom Publications

We have searched for a heavy resonance decaying into a Z+ jet final state in pp̅ collisions at a center of mass energy of 1:96 TeV at the Fermilab Tevatron collider using the D0 detector. No indication for such a resonance was found in a data sample corresponding to an integrated luminosity of 370 pb-1. We set upper limits on the cross section times branching fraction for heavy resonance production at the 95% C.L. as a function of the resonance mass and width. The limits are interpreted within the framework of a specific model of excited quark …

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An Automated Algorithm For The Identification Of Artifacts In Mottled And Noisy Images, Onome Augustine Ugbeme Jul 2006

An Automated Algorithm For The Identification Of Artifacts In Mottled And Noisy Images, Onome Augustine Ugbeme

Theses

This thesis proposes an algorithm for automatically classifying a specific set of image quality (IQ) defects on noisy and mottled printed documents. A rough initial estimate of the defects' location i.e. defect detection is manually provided with a scanned image. The approach then proceeds to derive a more accurate segmentation by performing several image processing routines on the digital image. This reveals regions of interest from which discriminatory features are extracted. A classification of four defects is achieved via a customized tree classifier which employs a combination of size, shape and region attributes at corresponding nodes to yield appropriate binary …

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2006-07-12 Unm News Minute, University Of New Mexico Communication And Marketing Department Jul 2006

2006-07-12 Unm News Minute, University Of New Mexico Communication And Marketing Department

UNM News Minute 2006

No abstract provided.

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2006-07-12 Unm News Minute, University Of New Mexico Communication And Marketing Department Jul 2006

2006-07-12 Unm News Minute, University Of New Mexico Communication And Marketing Department

UNM News Minute 2006

No abstract provided.

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Daily Eastern News: July 11, 2006, Eastern Illinois University Jul 2006

Daily Eastern News: July 11, 2006, Eastern Illinois University

July

No abstract provided.

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Fourteen Students From Four States Granted Honors College Scholarships, Edwin Smith Jul 2006

Fourteen Students From Four States Granted Honors College Scholarships, Edwin Smith

University of Mississippi News

Fourteen outstanding high school graduates from Mississippi, Alabama, Louisiana and Tennessee have been chosen to receive prestigious scholarships from the Sally McDonnell Barksdale Honors College at the University of Mississippi.

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Dynamic Rank/Select Dictionaries With Applications To Xml Indexing, Ankur Gupta, Wing-Kai Hon, Rahul Shah, Jeffrey S. Vitter Jul 2006

Dynamic Rank/Select Dictionaries With Applications To Xml Indexing, Ankur Gupta, Wing-Kai Hon, Rahul Shah, Jeffrey S. Vitter

Department of Computer Science Technical Reports

No abstract provided.

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Tracing Lineage In Multi-Version Scientific Databases, Mingwu Zhang, Daisuke Kihara, Sunil Prabhakar Jul 2006

Tracing Lineage In Multi-Version Scientific Databases, Mingwu Zhang, Daisuke Kihara, Sunil Prabhakar

Department of Computer Science Technical Reports

No abstract provided.

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Permutation Methods In Relative Risk Regression Models, Wenyu Jiang, Jack Kalbfleisch Jul 2006

Permutation Methods In Relative Risk Regression Models, Wenyu Jiang, Jack Kalbfleisch

The University of Michigan Department of Biostatistics Working Paper Series

In this paper, we develop a weighted permutation (WP) method to construct confidence intervals for regression parameters in relative risk regression models. The WP method is a generalized permutation approach. It constructs a resampled history which mimics the observed history for individuals under study. Inference procedures are based on studentized score statistics that are insensitive to the forms of the relative risk function. This makes the WP method appealing in the general framework of the relative risk regression model. First order accuracy of the WP method is established using the counting process approach with a partial likelihood filtration. A simulation …

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Current, July 10, 2006, University Of Missouri-St. Louis Jul 2006

Current, July 10, 2006, University Of Missouri-St. Louis

Current (2000s)

Orientation Issue

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Extreme Ground Motion Studies, John G. Anderson, James N. Brune, Amy J. Smiecinski, Raymond E. Keeler Jul 2006

Extreme Ground Motion Studies, John G. Anderson, James N. Brune, Amy J. Smiecinski, Raymond E. Keeler

Publications (YM)

This project consists of two separate investigations into extreme ground motions due to seismic events. First, it includes field studies of geological formations that should put an upper bound on extreme ground motions that have happened at the site of the formations. The locations are critically selected to provide the most effective constraints possible on the validity of the probabilistic seismic hazard analysis for Yucca Mountain. Second, this project surveys recorded ground motions from around the world, and aims to draw general conclusions from these as to the conditions where extreme ground motions are observed.

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Improving Record Linkage Through Pedigrees, Burdette N. Pixton Jul 2006

Improving Record Linkage Through Pedigrees, Burdette N. Pixton

Theses and Dissertations

Record linkage, in a genealogical context, is the process of identifying individuals from multiple sources which refer to the same real-world entity. Current solutions focus on the individuals in question and on complex rules developed by human experts. Genealogical databases are highly-structured with relationships existing between the individuals and other instances. These relationships can be utilized and human involvement greatly minimized by using a filtered structured neural network. These neural networks, using traditional back-propagation methods, are biased in a way to make the network human readable. The results show an increase in precision and recall when pedigree data is available …

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Study Of Same-Lane And Inter-Lane Gvw Correlation, Colin C. Caprani, Bernard Enright, E. J. O'Brien Jul 2006

Study Of Same-Lane And Inter-Lane Gvw Correlation, Colin C. Caprani, Bernard Enright, E. J. O'Brien

Conference papers

Extensive work has been done over the last two decades on the simulation of traffic loading on bridges. The methodology used is to generate a number of years of simulated traffic and to use extreme value statistics to predict more accurately the characteristic loading for a given bridge. The parameters and probability distributions used in the Monte Carlo simulation must be based on observed sample traffic data. Some previous studies have made unsubstantiated assumptions regarding correlation between the Gross Vehicle Weights (GVW) of trucks in the same lane, or between trucks in adjacent, same direction lanes. For this paper, an …

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How Does Being Placed In A Special Education Setting Affect A Student's Self-Concept?, Kristin Fastiggi Jul 2006

How Does Being Placed In A Special Education Setting Affect A Student's Self-Concept?, Kristin Fastiggi

Theses and Dissertations

The purpose of this study was to compare the self-concept of classified and non-classified students. Twenty-four students, twelve classified and twelve non-classified, all from Gloucester County, were given the Rosenberg Self-Esteem Scale. The test consisted of ten statements related to overall feelings of self-worth or self-acceptance. The students were tested away from their peers and the test was administered by the researcher. Once the study had been carried out the scores were analyzed by the researcher. The non-classified group had an average score of 15.83 (a normal self-esteem is within the range of 15-25). The non-classified group had an average …

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Sensitivity Of Biomechanical Measures To Evaluate The Effects Of Seated Whole-Body Vibration, B. Santos, A. Delisle, C. Larivière, A. Plamondon, D. Imbeau Jul 2006

Sensitivity Of Biomechanical Measures To Evaluate The Effects Of Seated Whole-Body Vibration, B. Santos, A. Delisle, C. Larivière, A. Plamondon, D. Imbeau

Affiches

No abstract provided.

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Syncsql: A Language To Express Views Over Data Streams, Thanaa M. Ghanem, Per-Ake Larson, Walid G. Aref, Ahmed K. Elmagarmid Jul 2006

Syncsql: A Language To Express Views Over Data Streams, Thanaa M. Ghanem, Per-Ake Larson, Walid G. Aref, Ahmed K. Elmagarmid

Department of Computer Science Technical Reports

No abstract provided.

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Jumpstarting Phylogenetic Searches, Jesse Lewis Mecham Jul 2006

Jumpstarting Phylogenetic Searches, Jesse Lewis Mecham

Theses and Dissertations

Phylogenetic analysis is a central tool in studies of comparative genomics. When a new region of DNA is isolated and sequenced, researchers are often forced to throw away months of computation on an existing phylogeny of homologous sequences in order to incorporate this new sequence. The previously constructed trees are often discarded, and the researcher begins the search again from scratch. The jumpstarting algorithm uses trees from the prior search as a starting point for a new phylogenetic search. This technique drastically decreases search time for large data sets. This kind of analysis is necessary as researchers analyze tree of …

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Three Iwu Professors, Chaplain Set To Retire, Sherry Wallace Jul 2006

Three Iwu Professors, Chaplain Set To Retire, Sherry Wallace

News and Events (Discontinued Series)

No abstract provided.

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Inverting Color-Magnitude Diagrams To Access Precise Star Cluster Parameters: A Bayesian Approach, Ted Von Hippel, Et Al. Jul 2006

Inverting Color-Magnitude Diagrams To Access Precise Star Cluster Parameters: A Bayesian Approach, Ted Von Hippel, Et Al.

Publications

We demonstrate a new Bayesian technique to invert color-magnitude diagrams of main-sequence and white dwarf stars to reveal the underlying cluster properties of age, distance, metallicity, and line-of-sight absorption, as well as individual stellar masses. The advantages our technique has over traditional analyses of color-magnitude diagrams are objectivity, precision, and explicit dependence on prior knowledge of cluster parameters. Within the confines of a given set of often-used models of stellar evolution, a single mapping of initial to final masses, and white dwarf cooling, and assuming photometric errors that one could reasonably achieve with the Hubble Space Telescope, our technique …

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Parallel Operation Of Hybrid Loaded Resonant Converter Using Phase-Shift Control, Taufik, James J. Mullins Jul 2006

Parallel Operation Of Hybrid Loaded Resonant Converter Using Phase-Shift Control, Taufik, James J. Mullins

Electrical Engineering

This paper presents a phase shifting method to adjust the combined output voltage of two hybrid loaded resonant converters connected in parallel. The method implements a fixed switching frequency and hence it is particularly useful in applications such as medical instrumentation where audible noise is not desirable. The design and analysis of parallel hybrid resonant converters operating in discontinuous conduction mode using the phase shifting method is described. Computer simulation to prove the feasibility of the phase shifting method in the design example is also provided. Analysis of the characteristics of the output voltage produced by phase shifting control along …

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The Combination Of Ecological And Case-Control Data, Sebastien Haneuse, Jon Wakefield Jul 2006

The Combination Of Ecological And Case-Control Data, Sebastien Haneuse, Jon Wakefield

UW Biostatistics Working Paper Series

Ecological studies, in which data are available at the level of the group, rather than at the level of the individual, are susceptible to a range of biases due to their inability to characterize within-group variability in exposures and confounders. In order to overcome these biases, we propose a hybrid design in which ecological data are supplemented with a sample of individual-level case-control data. We develop the likelihood for this design and illustrate its benefits via simulation, both in bias reduction when compared to an ecological study, and in efficiency gains relative to a conventional case-control study. An interesting special …

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A Stratigraphic And Geochronologic Analysis Of The Morrison Formation/Cedar Mountain Formation Boundary, Utah, Brent W. Greenhalgh Jul 2006

A Stratigraphic And Geochronologic Analysis Of The Morrison Formation/Cedar Mountain Formation Boundary, Utah, Brent W. Greenhalgh

Theses and Dissertations

The Lower Cretaceous Cedar Mountain Formation preserves several vertebrate faunas and has the potential of providing critical timing information pertaining to Early Cretaceous dinosaurs and the Sierran magmatic arc. Historically, the Morrison/Cedar Mountain contact and the duration of the unconformity between them have been difficult or impossible to determine because 1) the formations were deposited in similar environments, 2) the basal Cedar Mountain Formation is composed of reworked Morrison Formation, and 3) there are no radiometric ages for the lower Cedar Mountain Formation. A stratigraphic study through central Utah reveals a diagnostic suite of pedogenic and sedimentologic characters across the …

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Dna-Templated Surface Alignment And Characterization Of Carbon Nanotubes., Huijun Xin Jul 2006

Dna-Templated Surface Alignment And Characterization Of Carbon Nanotubes., Huijun Xin

Theses and Dissertations

Carbon nanotubes are appealing materials for nanofabrication due to their unique properties and structures. However, for carbon nanotubes to be used in mass-fabricated devices, precise control of nanotube orientation and location on surfaces is critical. I have developed a technique to align single-walled carbon nanotubes (SWNTs) on surfaces from a droplet of nanotube suspension under gas flow. Fluid motion studies indicate that alignment is likely due to circulation of SWNTs in the droplet. My work provides a facile method for generating oriented nanotubes for nanodevice applications. I have also devised an approach for localizing SWNTs onto 1-pyrenemethylamine-decorated DNA on surfaces. …

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On The Potential For Ill-Logic With Logically Defined Outcomes, Xianbin Li, Brian S. Caffo, Daniel O. Scharfstein Jul 2006

On The Potential For Ill-Logic With Logically Defined Outcomes, Xianbin Li, Brian S. Caffo, Daniel O. Scharfstein

Johns Hopkins University, Dept. of Biostatistics Working Papers

Logically defined outcomes are commonly used in medical diagnoses and epidemiological research. When missing values in the original outcomes exist, the method of handling the missingness can have unintended consequences, even if the original outcomes are missing completely at random. Complicating the issue is that the default behavior of standard statistical packages yields different results. In this paper, we consider two binary original outcomes, which are missing completely at random. For estimating the prevalence of a logically defined "or" outcome, we discuss the properties of four estimators: complete case estimator, all-available case estimator, maximum likelihood estimator (MLE), and moment-based estimator. …

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