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2008

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Articles 571 - 600 of 7321

Full-Text Articles in Physical Sciences and Mathematics

The Multinomial Regression Modeling Of The Cause-Of-Death Mortality Of The Oldest Old In The U.S., Dudley L. Poston Jr., Hosik Min Nov 2008

The Multinomial Regression Modeling Of The Cause-Of-Death Mortality Of The Oldest Old In The U.S., Dudley L. Poston Jr., Hosik Min

Journal of Modern Applied Statistical Methods

The statistical modeling of the causes of death of the oldest old (persons aged 80 and over) in the U.S. in 2001 was conducted in this article. Data were analyzed using a multinomial logistic regression model (MNLM) because multiple causes of death are coded on death certificates and the codes are nominal. The percentage distribution of the 10 major causes of death among the oldest old was first examined; we next estimated a multinomial logistic regression equation to predict the likelihood of elders dying of one of the causes of death compared to dying of an “other cause.” The independent …


Frequency Domain Modeling With Piecewise Constant Spectra, Erhard Reschenhofer Nov 2008

Frequency Domain Modeling With Piecewise Constant Spectra, Erhard Reschenhofer

Journal of Modern Applied Statistical Methods

Using piecewise constant functions as models for the spectral density of the differenced log real U.S. GDP it was found that these models have the capacity to compete with the spectral densities implied by ARMA models. According to AIC and BIC the piecewise constant spectral densities are superior to ARMA.


Cooling Of The Crust In The Neutron Star Low-Mass X-Ray Binary Mxb 1659-29, Edward M. Cackett, Rudy Wijnands, Jon M. Miller, Edward F. Brown, Nathalie Degenaar Nov 2008

Cooling Of The Crust In The Neutron Star Low-Mass X-Ray Binary Mxb 1659-29, Edward M. Cackett, Rudy Wijnands, Jon M. Miller, Edward F. Brown, Nathalie Degenaar

Physics and Astronomy Faculty Research Publications

In quasi-persistent neutron star transients, long outbursts cause the neutron star crust to be heated out of thermal equilibrium with the rest of the star. During quiescence, the crust then cools back down. Such crustal cooling has been observed in two quasi-persistent sources: KS 1731-260 and MXB 1659-29. Here we present an additional Chandra observation of MXB 1659-29 in quiescence, which extends the baseline of monitoring to 6.6 yr after the end of the outburst. This new observation strongly suggests that the crust has thermally relaxed, with the temperature remaining consistent over 1000 days. Fitting the temperature cooling curve with …


Selective Screenability In Topological Groups, Liljana Babinkostova Nov 2008

Selective Screenability In Topological Groups, Liljana Babinkostova

Mathematics Faculty Publications and Presentations

We examine the selective screenability property in topological groups. In the metrizable case we also give characterizations of Sc(Onbd,O) and Smirnov-Sc(Onbd,O) in terms of the Haver property and finitary Haver property respectively relative to left-invariant metrics. We prove theorems stating conditions under which Sc(Onbd,O) is preserved by products. Among metrizable groups we characterize the countable dimensional ones by a natural game.


Prey Behavior, Age-Dependent Vulnerability, And Predation Rates, Susan Lingle, Alex Feldman, Mark S. Boyce, W. Finbarr Wilson Nov 2008

Prey Behavior, Age-Dependent Vulnerability, And Predation Rates, Susan Lingle, Alex Feldman, Mark S. Boyce, W. Finbarr Wilson

Mathematics Faculty Publications and Presentations

Variation in the temporal pattern of vulnerability can provide important insights into predator-prey relationships and the evolution of antipredator behavior. We illustrate these points with a system that has coyotes (Canis latrans) as a predator and two species of congeneric deer (Odocoileus spp.) as prey. The deer employ different antipredator tactics (aggressive defense vs. flight) that result in contrasting patterns of age-dependent vulnerability in their probability of being captured when encountered by coyotes.We use longterm survival data and a simple mathematical model to show that (1) species differences in age-dependent vulnerability are reflected in seasonal predation rates …


Leading Firms As Knowledge Gatekeepers In A Networked Environment, Deogratias Harorimana Mr Nov 2008

Leading Firms As Knowledge Gatekeepers In A Networked Environment, Deogratias Harorimana Mr

Dr Deogratias Harorimana

This chapter introduces the role of the knowledge gatekeeper as a mechanism by which knowledge is created and transferred in a networked environment. Knowledge creation and transfer are essential for building a knowledge based economy. The chapter considers obstacles that inhibit this process and argues that leading firms create a shared socio-cultural context that enables the condivision of tacit meanings and codification of knowledge. Leading firms act as gatekeepers of knowledge through the creation of shared virtual platforms. There will be a leading firm that connects several networks of clients and suppliers may not interact directly with one another, but …


Survival Unchanged Five Months After Implementing The 2005 Aha Cpr And Ecc Guidelines For Out-Of-Hospital Cardiac Arrest., Blair L. Bigham, Kent M. Koprowicz, John Stouffer, Tom P. Aufderheide, Stuart Donn, Judy Powell, Dan Davis, Sarah Nafziger, Brian Suffoletto, Ahamed Idris, Mike Helbock, Laurie J. Morrison Nov 2008

Survival Unchanged Five Months After Implementing The 2005 Aha Cpr And Ecc Guidelines For Out-Of-Hospital Cardiac Arrest., Blair L. Bigham, Kent M. Koprowicz, John Stouffer, Tom P. Aufderheide, Stuart Donn, Judy Powell, Dan Davis, Sarah Nafziger, Brian Suffoletto, Ahamed Idris, Mike Helbock, Laurie J. Morrison

Kent M Koprowicz

Introduction: To improve survival from out of hospital cardiac arrest (OHCA), the American Heart Association released guidelines in 2005. We examined the effect of these guidelines on survival in the Resuscitation Outcomes Consortium (ROC) Epistry – Cardiac Arrest. We hypothesized that survival would increase after guideline implementation. Methods: 174 EMS agencies from 8 of the 10 ROC sites were surveyed to determine 2005 AHA guideline implementation, or crossover, date. Two sites with 2005 compatible treatment algorithms prior to guideline release were not included. Patients with OHCA secondary to a non cardiac cause, EMS witnessed events, patients <18 years>old, and patients with …


Una Comparazione Tra Le Reti Di Amministratori Nelle Principali Societa Quotate In Italia, Francia E Gran Bretagna, Paolo Santella, Carlo Drago, Andrea Polo, Enrico Gagliardi Nov 2008

Una Comparazione Tra Le Reti Di Amministratori Nelle Principali Societa Quotate In Italia, Francia E Gran Bretagna, Paolo Santella, Carlo Drago, Andrea Polo, Enrico Gagliardi

Carlo Drago

The purpose of the present paper is to contribute to the empirical literature on country interlocks by illustrating and analysing the interlocking directorships in the first 40 Italian, French and British Blue Chips as of December 2007 (Italy)/March 2008 (France and uk). The theoretical literature identify two possible explanations for interlocking directorships, on the one hand the collusion among players in the same market or in general among enterprises that have business relations among themselves; on the other hand the interest for enterprises to have on their boards bankers, suppliers, and clients so as to reduce information asymmetries. Our findings …


Book Ii, Otto Vogl: Papers And Patents, 1970-1977, Jane C. Vogl Nov 2008

Book Ii, Otto Vogl: Papers And Patents, 1970-1977, Jane C. Vogl

Otto Vogl

Books I-XII include citations to Otto Vogl's publications and patents. Printed versions of these twelve volumes are also available in the Integrated Sciences and Engineering Library of the University of Massachusetts in Amherst. MA, Lederle Graduate Research Center. The printed volumes include the full reprints of all cited publications.


Asymptotic Behavior Of Linearized Viscoelastic Flow Problem, Yinnian He, Yi Li Nov 2008

Asymptotic Behavior Of Linearized Viscoelastic Flow Problem, Yinnian He, Yi Li

Yi Li

In this article, we provide some asymptotic behaviors of linearized viscoelastic flows in a general two-dimensional domain with certain parameters small and the time variable large.


Locating Oil Spills Under Sea Ice Using Ground-Penetrating Radar, John H. Bradford, Lee M. Liberty, David F. Dickens Nov 2008

Locating Oil Spills Under Sea Ice Using Ground-Penetrating Radar, John H. Bradford, Lee M. Liberty, David F. Dickens

CGISS Publications and Presentations

The accelerating level of interest in arctic oil and gas exploration was demonstrated in the overwhelming response to recent lease sales in the Alaskan OCS region. As development increases, the potential for accidental oil spills in the arctic marine environment increases. The need for reliable systems to detect oil trapped in a range of ice conditions remains at the forefront of continued efforts to improve response to ocean spills.


Supply Curves For Rooftop Solar Pv-Generated Electricity For The United States, Paul Denholm, Robert Margolis Nov 2008

Supply Curves For Rooftop Solar Pv-Generated Electricity For The United States, Paul Denholm, Robert Margolis

Publications (E)

In this report, we examine several possible methods for generating PV supply curves based exclusively on rooftop deployment. We begin by introducing a framework methodology for a basic supply curve based on estimated distribution of population and buildings, rooftop availability and orientation, and geographical variation in resource. We then discuss limitations to this basic methodology and introduce alternative supply curves that consider additional factors – changes in PV efficiency and configuration, rooftop availability, and grid limitations – while emphasizing the data and methodological limitations to each approach. The resulting curves potentially could be used as inputs to other models or …


Localised Galvanic Corrosion Processes In Thermal Spray Coated/Cast Aluminium Alloy Systems, David Culliton, Tony Betts, David Kennedy Nov 2008

Localised Galvanic Corrosion Processes In Thermal Spray Coated/Cast Aluminium Alloy Systems, David Culliton, Tony Betts, David Kennedy

Conference Papers

Cast Aluminium Alloys, because of the propensity of aluminium to react with impurities and alloying elements, are prone to developing IM impurities during the solidification process. These IM phases can act, in some fluids, as initiation sites for localised corrosion processes, resulting in degradation phenomena, such as pitting. Whilst Thermal Spray coatings can improve the wear resistance of Cast Aluminium Alloys, their corrosion performance may be hampered by the presence of through porosity within the coating.

The present work details some preliminary studies of the localised corrosion processes occurring at the interface area between a Thermal Spray coating and a …


Geosciences Newsletter - Fall 2008, Department Of Geosciences Nov 2008

Geosciences Newsletter - Fall 2008, Department Of Geosciences

Geological and Environmental Sciences News

Vol. 3, No. 3

  • Faculty Updates
  • Publications
  • Grants
  • MGRRE
  • New Courses
  • Graduate News
  • Awards
  • Field Trips
  • Alumni
  • Development
  • Advisory Board


Focus On Rna Isolation: Obtaining Rna For Microrna (Mirna) Expression Profiling Analyses Of Neural Tissue, Wang-Xia Wang, Bernard R. Wilfred, Donald A. Baldwin, R. Benjamin Isett, Na Ren, Arnold J. Stromberg, Peter T. Nelson Nov 2008

Focus On Rna Isolation: Obtaining Rna For Microrna (Mirna) Expression Profiling Analyses Of Neural Tissue, Wang-Xia Wang, Bernard R. Wilfred, Donald A. Baldwin, R. Benjamin Isett, Na Ren, Arnold J. Stromberg, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

MicroRNAs (miRNAs) are present in all known plant and animal tissues and appear to be somewhat concentrated in the mammalian nervous system. Many different miRNA expression profiling platforms have been described. However, relatively little research has been published to establish the importance of 'upstream' variables in RNA isolation for neural miRNA expression profiling. We tested whether apparent changes in miRNA expression profiles may be associated with tissue processing, RNA isolation techniques, or different cell types in the sample. RNA isolation was performed on a single brain sample using eight different RNA isolation methods, and results were correlated using a conventional …


Toward Evaluating Lighting Design Interface Paradigms For Novice Users, William Brandon Kerr, Fabio Pellacini Nov 2008

Toward Evaluating Lighting Design Interface Paradigms For Novice Users, William Brandon Kerr, Fabio Pellacini

Computer Science Technical Reports

Lighting design is a complex and fundamental task in computer cinematography, involving adjustment of light parameters to define final scene appearance. Many lighting interfaces have been proposed to improve lighting design work flow. These paradigms exist in three paradigm categories: direct light parameter manipulation, indirect light feature manipulation (e.g., shadow dragging), and goal-based optimization of light through painting. To this date, no formal evaluation of the relative effectiveness of these methods has been performed. In this paper, we present a first step toward evaluating the three paradigms in the form of a user study with novice users. We focus our …


A Window On The Fifth Dimension, Frank A. Farris Nov 2008

A Window On The Fifth Dimension, Frank A. Farris

Mathematics and Computer Science

Is there enough mathematics in your home? What visual aids do you keep on hand for that inevitable moment when guests want to know why you spend your life on mathematics? Feeling a lack in this area, I commissioned glass artist Hans Schepker to produce a window - from the fifth dimension? - based on an image that came up in my research. It turned out splendidly, and you can see it on the cover of this issue of MAA FOCUS.


Final Report: Section 1. Introduction, Horsley Witten Group, Inc. Nov 2008

Final Report: Section 1. Introduction, Horsley Witten Group, Inc.

Phase I Final Report

No abstract provided.


Final Report: Watershed Database, Horsley Witten Group, Inc. Nov 2008

Final Report: Watershed Database, Horsley Witten Group, Inc.

Phase I Final Report

No abstract provided.


Final Report: Section 8. Phase Ii Scope Of Services, Horsley Witten Group, Inc. Nov 2008

Final Report: Section 8. Phase Ii Scope Of Services, Horsley Witten Group, Inc.

Phase I Final Report

No abstract provided.


Final Report: Section 7. Conclusions And Additional Comments, Horsley Witten Group, Inc. Nov 2008

Final Report: Section 7. Conclusions And Additional Comments, Horsley Witten Group, Inc.

Phase I Final Report

No abstract provided.


Final Report: Appendix A. Water Balance Analysis Assumptions, Horsley Witten Group, Inc. Nov 2008

Final Report: Appendix A. Water Balance Analysis Assumptions, Horsley Witten Group, Inc.

Phase I Final Report

No abstract provided.


Final Report: Section 3. Public Outreach, Horsley Witten Group, Inc. Nov 2008

Final Report: Section 3. Public Outreach, Horsley Witten Group, Inc.

Phase I Final Report

No abstract provided.


Final Report: Section 6. Smart Growth Case Study – Easton, Horsley Witten Group, Inc. Nov 2008

Final Report: Section 6. Smart Growth Case Study – Easton, Horsley Witten Group, Inc.

Phase I Final Report

No abstract provided.


Final Report: Section 2. Data Collection, Horsley Witten Group, Inc. Nov 2008

Final Report: Section 2. Data Collection, Horsley Witten Group, Inc.

Phase I Final Report

No abstract provided.


Final Report: Cover, Acknowledgement, Table Of Contents, List Of Figures And List Of Tables, Horsley Witten Group, Inc. Nov 2008

Final Report: Cover, Acknowledgement, Table Of Contents, List Of Figures And List Of Tables, Horsley Witten Group, Inc.

Phase I Final Report

No abstract provided.


Final Report: Executive Summary, Horsley Witten Group, Inc. Nov 2008

Final Report: Executive Summary, Horsley Witten Group, Inc.

Phase I Final Report

No abstract provided.


Final Report: Section 4. Sub-Watershed Analysis – Water Balance, Horsley Witten Group, Inc. Nov 2008

Final Report: Section 4. Sub-Watershed Analysis – Water Balance, Horsley Witten Group, Inc.

Phase I Final Report

No abstract provided.


Final Report: Water And Sewer Service Area Maps (By Town), Horsley Witten Group, Inc. Nov 2008

Final Report: Water And Sewer Service Area Maps (By Town), Horsley Witten Group, Inc.

Phase I Final Report

No abstract provided.


Final Report: Section 5. Stream Buffer And Habitat Analysis, Horsley Witten Group, Inc. Nov 2008

Final Report: Section 5. Stream Buffer And Habitat Analysis, Horsley Witten Group, Inc.

Phase I Final Report

No abstract provided.