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166743 full-text articles. Page 4234 of 4241.

Combinatorial Analysis, David Bressoud 2009 Macalester College

Combinatorial Analysis, David Bressoud

David Bressoud

No abstract provided.


Lost In Translation? A Boundary Work Perspective On Making Climate Change Governable, Robert Hoppe 2009 University of Twente

Lost In Translation? A Boundary Work Perspective On Making Climate Change Governable, Robert Hoppe

Robert Hoppe

No abstract provided.


The Relationship Between Trade, Investment And Environment: Some Empirical Findings, Debashis Chakraborty, Sacchidananda Mukherjee 2009 National Institute of Public Finance and Policy (NIPFP), New Delhi

The Relationship Between Trade, Investment And Environment: Some Empirical Findings, Debashis Chakraborty, Sacchidananda Mukherjee

Sacchidananda Mukherjee

The interlinkage between economic openness and environmental repercussions is a widely researched area. The current study contributes in the existing pool of research by conducting a cross-country empirical analysis for the year 2008 by exploring the interrelationship between openness indicators (trade and investment) and environmental performance of a country. For this purpose, the analysis separately considers export orientation, import orientation, FDI inwardness and FDI outwardness of the countries in different variations of the proposed empirical model. The regression results do not provide strong support to the Pollution Haven Hypothesis (PHH). The findings also confirm a relationship between socio-economic and socio-political ...


Sphet: Spatial Models With Heteroskedastic Innovations In R, Gianfranco Piras 2009 Regional Research Institute, West Virginia University

Sphet: Spatial Models With Heteroskedastic Innovations In R, Gianfranco Piras

Gianfranco Piras

No abstract provided.


Kinetic And Mechanistic Studies Of The Deuterium Exchange In Classical Keto−Enol Tautomeric Equilibrium Reactions, Mark Waner, Michael Nichols 2009 John Carroll University

Kinetic And Mechanistic Studies Of The Deuterium Exchange In Classical Keto−Enol Tautomeric Equilibrium Reactions, Mark Waner, Michael Nichols

Mark J. Waner

An extension of the classic keto−enol tautomerization of β-dicarbonyl compounds into a kinetic analysis of deuterium exchange is presented. It is shown that acetylacetone and ethyl acetoacetate undergo nearly complete deuterium exchange of the α-methylene carbon when dissolved in methanol-d4. The extent of deuteration may be monitored via NMR spectroscopy as a function of time. A mechanism for deuterium exchange is presented and shown to be consistent with a consecutive first-order process. The data for acetylacetone are consistent with steady-state kinetics, whereas those of ethyl acetoacetate illustrate nonsteady-state behavior, offering an accessible example where students might collect and analyze ...


Mitigation And The Geoengineering Threat, Juan Moreno-Cruz 2009 University of Calgary

Mitigation And The Geoengineering Threat, Juan Moreno-Cruz

Juan B. Moreno-Cruz

Recent scientific advances have introduced the possibility of engineering the climate system to lower ambient temperatures without lowering greenhouse gas concentrations. This possibility has created an intense debate given the ethical, moral and scientific questions it raises. In this paper I examine the economic issues introduced when geoengineering becomes available in a standard two-period two-country model where strategic interaction leads to suboptimal mitigation. Geoengineering introduces the possibility of technical substitution away from mitigation, but it also affects the strategic interaction across countries: mitigation decisions made in the first period directly affect the geoengineering decisions made in the second period. With ...


Bias.Pboot, Susan Gruber, Kristin Porter, Maya Petersen, Yue Wang, Mark van der Laan 2009 University of California - Berkeley

Bias.Pboot, Susan Gruber, Kristin Porter, Maya Petersen, Yue Wang, Mark Van Der Laan

Susan Gruber

bias.pboot is R software for diagnosing positivity bias using a parametric bootstrap


Challenging Challenge Questions: An Experimental Analysis Of Authentication Technologies And User Behaviour, Mike Just, David Aspinall 2009 Glasgow Caledonian University

Challenging Challenge Questions: An Experimental Analysis Of Authentication Technologies And User Behaviour, Mike Just, David Aspinall

Dr. Mike Just

To authenticate human users to systems, challenge questions based on personal information are often used, typically when a primary authentication credential, such as a password, is forgotten. This ought to be a trustworthy mechanism, that is both reliable and accurate: personal information should be inherently memorable and not known to others. However, concerns have been raised recently about these assumptions: for example, some commonly used questions may be based on information that is available publicly. A possible improvement, then, is to allow users to choose their own questions. Here we report on an experiment which gathered user chosen questions and ...


Ans Binding Reveals Common Features Of Cytotoxic Amyloid Species, Benedetta Bolognesi, Janet Kumita, Teresa Barros, Elin Esbjorner, Leila Luheshi, Damian Crowther, Mark Wilson, Christopher Dobson, Giorgio Favrin, Justin Yerbury 2009 University of Cambridge

Ans Binding Reveals Common Features Of Cytotoxic Amyloid Species, Benedetta Bolognesi, Janet Kumita, Teresa Barros, Elin Esbjorner, Leila Luheshi, Damian Crowther, Mark Wilson, Christopher Dobson, Giorgio Favrin, Justin Yerbury

Mark R Wilson

Oligomeric assemblies formed from a variety of disease-associated peptides and proteins have been strongly associated with toxicity in many neurodegenerative conditions, such as Alzheimer's disease. The precise nature of the toxic agents, however, remains still to be established. We show that prefibrillar aggregates of E22G (arctic) variant of the A beta(1-42) peptide bind strongly to 1-anilinonaphthalene 8-sulfonate and that changes in this property correlate significantly with changes in its cytotoxicity. Moreover, we show that this phenomenon is common to other amyloid systems, such as wild-type A beta(1-42), the 159T variant of human lysozyme and an SH3 domain ...


Thin-Type Dense Sets And Related Properties, Jennifer Hutchison 2009 Cedarville University

Thin-Type Dense Sets And Related Properties, Jennifer Hutchison

Jennifer D. Hutchison, Ph.D.

Dense sets in topological spaces may be thought of as those which are ubiquitous. We discuss dense sets in product spaces which also have a thin-type property, making them in some sense rare or spread out. Thin-type propertiesinclude the previously studied properties thin, very thin, and slim. We construct examples showing that even in a separable space, there may be no countable very thin or slim dense set. We also define and discuss the properties <κ -thin, codimension 1 slim, and superslim. The definition of < κ -thin is between those of thin and very thin; the definition of superslim is ...


Oscillatory And Monotonic Modes Of Long-Wave Marangoni Convection In A Thin Film, Sergey Shklyaev, Mikhail Khenner, Alexei Alabuzhev 2009 Western Kentucky University

Oscillatory And Monotonic Modes Of Long-Wave Marangoni Convection In A Thin Film, Sergey Shklyaev, Mikhail Khenner, Alexei Alabuzhev

Mikhail Khenner

We study long-wave Marangoni convection in a layer heated from below. Using the scaling k=O#1;#3;Bi#2;, where k is the wave number and Bi is the Biot number, we derive a set of amplitude equations. Analysis of this set shows presence of monotonic and oscillatory modes of instability. Oscillatory mode has not been previously found for such direction of heating. Studies of weakly nonlinear dynamics demonstrate that stable steady and oscillatory patterns can be found near the stability threshold.


Accounting For Response Misclassification And Covariate Measurement Error Improves Powers And Reduces Bias In Epidemiologic Studies, Dunlei Cheng, Adam Branscum, James Stamey 2009 Baylor Health Care System

Accounting For Response Misclassification And Covariate Measurement Error Improves Powers And Reduces Bias In Epidemiologic Studies, Dunlei Cheng, Adam Branscum, James Stamey

Dunlei Cheng

Purpose: To quantify the impact of ignoring misclassification of a response variable and measurement error in a covariate on statistical power, and to develop software for sample size and power analysis that accounts for these flaws in epidemiologic data. Methods: A Monte Carlo simulation-based procedure is developed to illustrate the differences in design requirements and inferences between analytic methods that properly account for misclassification and measurement error to those that do not in regression models for cross-sectional and cohort data. Results: We found that failure to account for these flaws in epidemiologic data can lead to a substantial reduction in ...


Spatially Resolved Polycyclic Aromatic Hydrocarbon Emission Features In Nearby, Low Metallicity, Star-Forming Galaxies, Korey Haynes, John Cannon, Evan Skillman, Dale Jackson, Robert Gehrz 2009 Macalester College

Spatially Resolved Polycyclic Aromatic Hydrocarbon Emission Features In Nearby, Low Metallicity, Star-Forming Galaxies, Korey Haynes, John Cannon, Evan Skillman, Dale Jackson, Robert Gehrz

John Cannon

No abstract provided.


Synthetic Mrna Cap Analogs With A Modified Triphosphate Bridge – Synthesis, Applications And Prospects, Jacek Jemielity, Joanna Kowalska, Anna Rydzik, Edward Darzynkiewicz 2009 University of Warsaw, Faculty of Physics, Division of Biophysics

Synthetic Mrna Cap Analogs With A Modified Triphosphate Bridge – Synthesis, Applications And Prospects, Jacek Jemielity, Joanna Kowalska, Anna Rydzik, Edward Darzynkiewicz

Joanna Kowalska

The cap structure was discovered at the 5′-end of the eukaryotic mRNA over three and a half decades ago. Since then, hundreds of chemically modified cap analogs have been synthesized and applied in numerous studies on the elucidation of cap-related physiological processes in the cell, and became important members of the biophosphate family. In this Perspective, we present recent developments in the synthesis of cap analogs modified within 5′,5′-triphosphate bridges and their utility for interdisciplinary studies on cap-dependent processes in gene expression and its regulation, as well as biotechnological applications and perspectives in medicine.


The Generative Potential Of Community-Based Geographic Information Systems, Dirk Hovorka, Nancy Auerbach 2009 Bond University

The Generative Potential Of Community-Based Geographic Information Systems, Dirk Hovorka, Nancy Auerbach

Nancy Auerbach

No abstract provided.


Measuring E-Governance As An Innovation In The Public Sector, Devendra Potnis 2009 University of Tennessee, Knoxville

Measuring E-Governance As An Innovation In The Public Sector, Devendra Potnis

Devendra Potnis

Since 2001, the United Nations (UN) and affiliated organizations have measured e-Government initiatives of more than 178 Member States of the UN, by devising “e-Government Readiness Index” (e-GRI) and “e-Participation Index” (e-PI). The UN has published rankings for its Member States in terms of e-GRI and e-PI, through e-Government Readiness Assessments (Surveys). Member States of the UN and digital government research community as well as academicians and practitioners regularly use the e-GRI and e-PI as a point-of-reference; this fact alone signifies the importance of evaluating the existing UN methodologies assessing e-Governance. Since e-Governance is one of the greatest innovations in ...


College Algebra In Context With Applications To The Managerial, Life, And Social Sciences, Ronald Harshbarger, Lisa Yocco 2009 University of South Carolina - Beaufort

College Algebra In Context With Applications To The Managerial, Life, And Social Sciences, Ronald Harshbarger, Lisa Yocco

Lisa S. Yocco

Harshbarger/Yocco’s College Algebra in Context with Applications for the Managerial, Life, and Social Sciences, Third Edition uses modeling and real-data problems to develop the skills that students will need for their future courses and careers. Applications anticipate the math that students will encounter in their professional lives, giving them the practice they need to become adept problem-solvers. Every chapter begins with the Algebra Toolbox, which reviews the skills and concepts necessary to master the material ahead. This new full-color edition offers a greater number of technology tips, and the content has been reorganized to accommodate a wide range ...


A Comparative Study Of Lithium And Sodium Salts In Pan-Based Ion Conducting Polymer Electrolytes, Zurina Osman 2009 University of Malaya

A Comparative Study Of Lithium And Sodium Salts In Pan-Based Ion Conducting Polymer Electrolytes, Zurina Osman

Zurina Osman

The conducting polymer electrolyte films consisting of polyacrylonitrile (PAN) as the host polymer, lithium triflate (LiCF(3)SO(3)) and sodium triflate (NaCF(3)SO(3)) as inorganic salts were prepared by the solution-cast technique. The pure PAN film was prepared as a reference. The ionic conductivity for the films is characterized using impedance spectroscopy. The room temperature conductivity for the PAN + 26 wt.% LiCF(3)SO(3) film and the PAN + 24 wt.% NaCF(3)SO(3) film is 3.04 x 10(-4) S cm(-1) and 7.13 x 10(-4) S cm(-1), respectively. XRD studies ...


An Analysis Of Temperature Variations Using Remote Sensing Approach In Lokoja Area, Fanan Ujoh, Olarewaju Ifatimehin, Sunday Ishaya 2009 Benue State University

An Analysis Of Temperature Variations Using Remote Sensing Approach In Lokoja Area, Fanan Ujoh, Olarewaju Ifatimehin, Sunday Ishaya

Dr. Fanan Ujoh

This study investigates the thermal variations of the different land use/cover types in urban Lokoja town retrieved from Landsat TM imagery of 1987. Band 2, 3, 4 and 6 of the imagery were used in the classification, estimation of NDVI, land surface emissivity values, and satellite sensor temperature. The Qin et al’s mono window algorithm was employed to obtain the land surface temperatures of the different land use/cover types classified. The results indicate that there is a significant variation in temperatures among the different land use/cover types in Lokoja. The built up area and the vacant ...


Efficient Secret Handshaking Protocol, Maged Ibrahim 2009 Helwan University

Efficient Secret Handshaking Protocol, Maged Ibrahim

Maged Ibrahim

Secret handshaking protocols allow two members of the same group to identify each other secretly, i.e., any two parties who are members of the same group will recognize each other as members, yet, a party which is not a member of this group cannot tell, by engaging some party in the handshaking protocol, whether that party is a member of this group. Unlinkability is one of the main merits of secret handshaking protocols, that is, a party engaged in at least two handshakes must not be able to link any two different handshakes to a particular party. To achieve ...


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