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2006

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Articles 2611 - 2640 of 5872

Full-Text Articles in Physical Sciences and Mathematics

Α-Vinylic Amino Acids: Occurrence, Asymmetric Synthesis, And Biochemical Mechanisms, David B. Berkowitz, Bradley D. Charette, Kannan Karukurichi, Jill M. Mcfadden Apr 2006

Α-Vinylic Amino Acids: Occurrence, Asymmetric Synthesis, And Biochemical Mechanisms, David B. Berkowitz, Bradley D. Charette, Kannan Karukurichi, Jill M. Mcfadden

David Berkowitz Publications

This report presents an overview of the family of naturally occurring “vinylic” amino acids, namely those that feature a C–C double bond directly attached to the α-carbon, along the side chain. Strategies that have been brought to bear on the stereo-controlled synthesis of these olefinic amino acids are surveyed. The mechanistic diversity by which such “vinylic triggers” can be actuated in a PLP (pyridoxal phosphate) enzyme active site is then highlighted by discussion of vinylglycine (VG), its substituted congeners, particularly AVG [4E-(2′-aminoethoxy)vinylglycine], and a naturally occurring VG-progenitor, SMM [(S)-methylmethionine].

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Some Significant Wildlife Strikes To Civil Aircraft In The United States, January 2005 –March 2006, Sandra E. Wright, Richard A. Dolbeer Apr 2006

Some Significant Wildlife Strikes To Civil Aircraft In The United States, January 2005 –March 2006, Sandra E. Wright, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

The U.S. Department of Agriculture, through an interagency agreement with the Federal Aviation Administration, compiles a database of all reported wildlife strikes to U.S. civil aircraft and to foreign carriers experiencing strikes in the USA. We have compiled over 66,000 strike reports from 1,565 airports, 1990-December 2005 (over 7,100 strikes in 2005), but estimate that this represents only about 20% of the strikes that have occurred. The following examples from the database since January 2005 are presented to show the serious impacts that strikes by birds or other wildlife can have on aircraft. These examples, from throughout the USA, demonstrate …

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Clir Forms Advisory Committee For Scholarly Communication Report, Ann Okerson, Gordon C. Tibbitts Apr 2006

Clir Forms Advisory Committee For Scholarly Communication Report, Ann Okerson, Gordon C. Tibbitts

Gordon C. Tibbitts III

In January 2006 CLIR (the Council on Library and Information Resources) formed a committee of advisors to develop strategically directed scholarly communication and preservation agendas that would appeal to and create value for CLIR constituents and the broader communities of stakeholders whose existence is entwined with these two topics. This report represents the findings as presented by Ann Okerson (the committee leader) and the committee findings between mid-January and late March 2006, identifying possible directions and studies to be pursued in CLIR's scholarly communication programs over the next three years.

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On The Growth Of The Betti Sequence Of The Canonical Module, David A. Jorgensen, Graham J. Leuschke Apr 2006

On The Growth Of The Betti Sequence Of The Canonical Module, David A. Jorgensen, Graham J. Leuschke

Mathematics - All Scholarship

We study the growth of the Betti sequence of the canonical module of a Cohen-Macaulay local ring. It is an open question whether this sequence grows exponentially whenever the ring is not Gorenstein. We answer the question of exponential growth affirmatively for a large class of rings, and prove that the growth is in general not extremal. As an application of growth, we give criteria for a Cohen-Macaulay ring possessing a canonical module to be Gorenstein.

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Temperature Dependence Of Magnetoresistance In Magnetic Tunnel Junctions With Different Free Layer Structures, L. Yuan, Sy_Hwang Liou, Dexin Wang Apr 2006

Temperature Dependence Of Magnetoresistance In Magnetic Tunnel Junctions With Different Free Layer Structures, L. Yuan, Sy_Hwang Liou, Dexin Wang

Department of Physics and Astronomy: Faculty Publications

The temperature and bias voltage dependence of magnetoresistance and the resistance of two types of magnetic tunnel junction (MTJ) samples were studied. These two types of MTJ samples have different free layer structures, while having the same pinned layer structures and with the same material for free and reference layers. The layer structure for type 1 MTJs is 80Ru-8CoFeB-15Al2O3-50CoFeB-9Ru-54FeCo- 350CrMnPt (in angstroms). The layer structure for type 2 MTJs is 80Ru-40CoFeB-50RuTa-40CoFeB- 15Al2O3-50CoFeB-9Ru-54FeCo-350CrMnPt. The tunneling magnetoresistance (TMR) ratio [(RAP-Rp)/Rp] is about 26% and 69% at room temperature for type 1 and type 2 MTJs, …

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West Nile Virus In North American Birds, Robert G. Mclean Apr 2006

West Nile Virus In North American Birds, Robert G. Mclean

United States Department of Agriculture Wildlife Services: Staff Publications

Following the introduction of West Nile virus (WNV) into the United States, in New York City in 1999, from its historical range in the eastern hemisphere, this mosquito-borne virus caused an intense outbreak in local bird populations and a small epidemic in the associated human population. West Nile virus became established in this focal area, and in 2000 it spread north and south from there during the summer transmission season. The virus continued to expand during the next six years, ultimately affecting all the continental states and most of North America. The strain of WNV introduced was uncharacteristically virulent as …

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Axiomatic Multi-Transport Bargaining: A Quantitative Method For Dynamic Transport Selection In Heterogeneous Multi-Transport Wireless Environments, Qiuyi Duan, Michael A. Goodrich, Charles D. Knutson, Lei Wang Apr 2006

Axiomatic Multi-Transport Bargaining: A Quantitative Method For Dynamic Transport Selection In Heterogeneous Multi-Transport Wireless Environments, Qiuyi Duan, Michael A. Goodrich, Charles D. Knutson, Lei Wang

Faculty Publications

Transport selection mechanisms are designed to facilitate seamless connectivity in heterogeneous multi-transport environments, allowing access to the “best” available transport according to user requirements. Evaluating transport configurations dynamically according to the user’s preferences and Quality of Service (QoS) requirements is a challenging task. This paper describes a quantitative approach that applies the Utility Theorem and Nash’s Bargaining solution to heterogeneous wireless environments. The mathematical model presented generates and adjusts the transport preference list dynamically depending on the degree to which a transport satisfies user preferences and the application’s QoS requirements. We incorporate a negotiation engine using the Axiomatic Multi-Transport Bargaining …

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Spectral Network (Specnet)—What Is It And Why Do We Need It?, John A. Gamon, A. F. Rahman, J. L. Dungan, M. Schildhauer, K. F. Huemmrich Apr 2006

Spectral Network (Specnet)—What Is It And Why Do We Need It?, John A. Gamon, A. F. Rahman, J. L. Dungan, M. Schildhauer, K. F. Huemmrich

United States National Aeronautics and Space Administration: Publications

Effective integration of optical remote sensing with flux measurements across multiple scales is essential for understanding global patterns of surface–atmosphere fluxes of carbon and water vapor. SpecNet (Spectral Network) is an international network of cooperating investigators and sites linking optical measurements with flux sampling for the purpose of improving our understanding of the controls on these fluxes. An additional goal is to characterize disturbance impacts on surface–atmosphere fluxes. To reach these goals, key SpecNet objectives include the exploration of scaling issues, development of novel sampling tools, standardization and intercomparison of sampling methods, development of models and statistical methods that relate …

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Image Interpretation Using Appraisal Analysis, Partha S. Routh, Carlyle R. Miller Apr 2006

Image Interpretation Using Appraisal Analysis, Partha S. Routh, Carlyle R. Miller

Geosciences Faculty Publications and Presentations

In geophysical inversion, a significant effort is invested to obtain images of the Earth from finite data. The first step is to obtain an image i.e. solve the inverse problem. This step alone provides significant challenges that are not addressed inthis paper. The next step is to interpret the image in terms of specific questions. For example, what can we say about the average value of a physical property within a certain region of the model? What scale information can we resolve from the data? These questions are problem dependent and may require that inversion be carried out several times …

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Modeling The Evolution Of Natural Organic Matter In The Environment With An Agent-Based Stochastic Approach, Xiaorong Xiang, Yingping Huang, Gregory Madey, Steve Cabaniss, Leilani Arthurs, Patricia Maurice Apr 2006

Modeling The Evolution Of Natural Organic Matter In The Environment With An Agent-Based Stochastic Approach, Xiaorong Xiang, Yingping Huang, Gregory Madey, Steve Cabaniss, Leilani Arthurs, Patricia Maurice

Department of Earth and Atmospheric Sciences: Faculty Publications

Natural organic matter (NOM) is ubiquitous in terrestrial and aquatic ecosystems, and it plays a crucial role in the evolution of soils, the transport of pollutants, and the global carbon cycle. NOM is a complex mixture of molecules and is thus heterogeneous in structure and composition. As NOM passes through an ecosystem, it is acted upon by a variety of processes, such as microbial degradation, adsorption to mineral surfaces, and photochemical reactions that can change its properties and reactivity. The evolution of NOM in space and time thus is an important research area in biology, geochemistry, ecology, soil science, and …

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Multiscale Image Registration, Dana C. Paquin, Doron Levy, Eduard Schreibmann, Lei Xing Apr 2006

Multiscale Image Registration, Dana C. Paquin, Doron Levy, Eduard Schreibmann, Lei Xing

Mathematics

A multiscale image registration technique is presented for the registration of medical images that contain significant levels of noise. An overview of the medical image registration problem is presented, and various registration techniques are discussed. Experiments using mean squares, normalized correlation, and mutual information optimal linear registration are presented that determine the noise levels at which registration using these techniques fails. Further experiments in which classical denoising algorithms are applied prior to registration are presented, and it is shown that registration fails in this case for significantly high levels of noise, as well. The hierarchical multiscale image decomposition of E. …

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Will Johnny/Joanie Make A Good Software Engineer?: Are Course Grades Showing The Whole Picture?, Jane Huffman Hayes, Alex Dekhtyar, Ashlee Holbrook, Olga Dekhtyar, Senthil Sundaram Apr 2006

Will Johnny/Joanie Make A Good Software Engineer?: Are Course Grades Showing The Whole Picture?, Jane Huffman Hayes, Alex Dekhtyar, Ashlee Holbrook, Olga Dekhtyar, Senthil Sundaram

Computer Science and Software Engineering

Predicting future success of students as software engineers is an open research area. We posit that current grading means do not capture all the information that may predict whether students will become good software engineers. We use one such piece of information, traceability of project artifacts, to illustrate our argument. Traceability has been shown to be an indicator of software project quality in industry. We present the results of a case study of a University of Waterloo graduate-level software engineering course where traceability was examined as well as course grades (such as mid-term, project grade, etc.). We found no correlation …

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On Potential Validity Of Document-Centric Xml Documents, Ionut E. Iacob, Alex Dekhtyar, Michael I. Dekhtyar Apr 2006

On Potential Validity Of Document-Centric Xml Documents, Ionut E. Iacob, Alex Dekhtyar, Michael I. Dekhtyar

Computer Science and Software Engineering

Document-centric XML document creation is a process of marking up textual content rather than typing text in a predefined structure. It turns out that, although the final document has to be valid with respect to the DTD/Schema used for the encoding, the "in-progress" document is almost never valid. At the same time, it is important to ensure that at each moment of time, the editor is working with an XML document that can be enriched with further markup to become valid. In this paper we explain the notion of potential validity of XML documents, which allows us to distinguish between …

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Mass Balance And Accumulation Rate Along Us Itase Routes, Gordon Hamilton Apr 2006

Mass Balance And Accumulation Rate Along Us Itase Routes, Gordon Hamilton

University of Maine Office of Research Administration: Grant Reports

The primary research activities in this project involved our participation in the four US ITASE field seasons (1999-2003). As part of the field program we collected ~5,500 km of continuous, precise GPS data along the traverse route. These geodetic data are used by ourselves and several other US ITASE investigators. We also installed 15 new mass balance (coffee can) stations in rarely visited regions of West and East Antarctica. Several shallow firn cores were collected to study local variability in snow accumulation around deeper 200-year ice core sites. As part of our collaboration with NASA, we performed detailed 3-dimensional mapping …

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Anaerobic Biodegradation Of Rdx And Tce: Single- And Dual-Contaminant Batch Tests, Travis S. M. Young, Matthew C. Morley, Daniel D. Snow Apr 2006

Anaerobic Biodegradation Of Rdx And Tce: Single- And Dual-Contaminant Batch Tests, Travis S. M. Young, Matthew C. Morley, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Several sites in the United States have groundwater contaminated with mixtures of high explosives and chlorinated solvents. This research examined the ability of two microbial cultures (anaerobic sludge and a facultative enrichment culture) to biodegrade single- and dual-contaminant mixtures of trichloroethene (TCE) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) under anaerobic conditions. In single component batch tests, both cultures degraded 0.6–1 mg RDX/L and its nitroso metabolites to below detection limits in <7 days. During initial 9-day TCE biodegradation tests, the anaerobic sludge did not transform TCE, whereas the facultative culture transformed approximately 10% of the initial 1.4 mg TCE/L. Prior to dual-contaminant batch tests, both cultures were grown in the presence of TCE. Subsequently, both acclimated cultures rapidly biodegraded mixtures of RDX and TCE. Both cultures degraded RDX and RDX-nitroso compounds to below detection limits in <4 days. In the same tests, TCE-acclimated anaerobic sludge converted TCE primarily to cis-dichloroethene (cis-DCE), while the acclimated facultative culture produced cis-DCE and other chlorinated metabolites. These preliminary results demonstrate that anaerobic bioremediation may be part of a feasible groundwater remediation …

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Variational Analysis Of Evolution Inclusions, Boris S. Mordukhovich Apr 2006

Variational Analysis Of Evolution Inclusions, Boris S. Mordukhovich

Mathematics Research Reports

The paper is devoted to optimization problems of the Bolza and Mayer types for evolution systems governed by nonconvex Lipschitzian differential inclusions in Banach spaces under endpoint constraints described by finitely many equalities and inequalities. with generally nonsmooth functions. We develop a variational analysis of such roblems mainly based on their discrete approximations and the usage of advanced tools of generalized differentiation satisfying comprehensive calculus rules in the framework of Asplund (and hence any reflexive Banach) spaces. In this way we establish extended results on stability of discrete approximations (with the strong W^1,2-convergence of optimal solutions under consistent perturbations of …

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Abstracts Of Papers, 84th Annual Meeting Of The Virginia Academy Of Science Apr 2006

Abstracts Of Papers, 84th Annual Meeting Of The Virginia Academy Of Science

Virginia Journal of Science

Full abstracts of papers for the 84th Annual Meeting of the Virginia Academy of Science, May 25-26, 2006, Virginia Polytechnic Institute and State University, Blacksburg, VA

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New Fellow: Robert A. Willis, Jr. Apr 2006

New Fellow: Robert A. Willis, Jr.

Virginia Journal of Science

Robert A. Willis, Jr. has been named Fellow of the Virginia Academy of Science. He has been an active member of the Virginia Academy of Science and the Association of Departments of Computer, Information Science/Engineering at Minority Institutions (ADMI) for nearly fifteen years.

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Absolute Magnitude Distributions And Light Curves Of Stripped-Envelope Supernovae, D. Richardson, D. Branch, E. Baron Apr 2006

Absolute Magnitude Distributions And Light Curves Of Stripped-Envelope Supernovae, D. Richardson, D. Branch, E. Baron

Faculty and Staff Publications

The absolute visual magnitudes of three Type IIb, 11 Type Ib, and 13 Type le supernovae (collectively known as stripped-envelope supernovae) are studied by collecting data on the apparent magnitude, distance, and interstellar extinction of each event. Weighted and unweighted mean absolute magnitudes of the combined sample, as well as various subsets of the sample, are reported. The limited sample size and the considerable uncertainties, especially those associated with extinction in the host galaxies, prevent firm conclusions regarding differences between the absolute magnitudes of supernovae of Types Ib and Ic, and regarding the existence of separate groups of over-luminous and …

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Stargazing: Observatories At Gettysburg College, 1874-Present, Andrew A. Carlson Apr 2006

Stargazing: Observatories At Gettysburg College, 1874-Present, Andrew A. Carlson

Hidden in Plain Sight Projects

Astronomy has long been a subject which has attracted the interest of man. Examples of early astronomers can be found in many ancient civilizations, including but not limited to, the Egyptians, the Chinese and the Greeks. As time passed the methods for interpreting the stars and theories that surrounded them changed concordant with the technology available. One of the largest breakthroughs in the world of astronomy was the invention of the telescope in the early seventeenth century. Often mis-attributed to Galileo (who was responsible for building the first reflecting telescope in 1688), the telescope was actually first designed by a …

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An Astronomical Account: A History Of Hatter Planetarium From 1966-2006, Jonathan D. Neu Apr 2006

An Astronomical Account: A History Of Hatter Planetarium From 1966-2006, Jonathan D. Neu

Hidden in Plain Sight Projects

When most individuals stare up at the vast dome of Hatter Planetarium, they often gaze upon the projected stars appearing on its surface, listening to an astronomical story told by one of its operators. However, there is a second story told by the planetarium itself. This story is the history of Hatter Planetarium, which spans five decades and includes the events in the lives of several individuals who have played a critical role in its existence at Gettysburg College. Its history has encompassed several phases of Gettysburg College traditions but is in danger of passing permanently and fixedly into the …

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Cs 142: Computer Programming - Ii, Ronald F. Taylor Apr 2006

Cs 142: Computer Programming - Ii, Ronald F. Taylor

Computer Science & Engineering Syllabi

Concepts introduced in CS 141 are developed in greater detail and depth with the Java programming language. Topics include object oriented programming, graphics, development of user interfaces and handling runtime errors with an emphasis on program verification and testing. Students must register for both lecture and one laboratory section. 4 credit hours. Prerequisite: CS 141 (Computer Programming I) and MTH 127 (College Algebra) or equivalent.

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Cs 206: Advanced Concepts/Techniques And Software Productivity Tools, John P. Herzog Apr 2006

Cs 206: Advanced Concepts/Techniques And Software Productivity Tools, John P. Herzog

Computer Science & Engineering Syllabi

By the end of this course, the students will have a greater depth of understanding in the areas of spreadsheets, databases, and presentation software using Microsoft Excel, Access, and PowerPoint.

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Cs 205-08: Computer Literacy And Office Automation, Kim Gros Apr 2006

Cs 205-08: Computer Literacy And Office Automation, Kim Gros

Computer Science & Engineering Syllabi

No abstract provided.

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Cs 208: Computer Programming For Business I, Dennis Kellermeier Apr 2006

Cs 208: Computer Programming For Business I, Dennis Kellermeier

Computer Science & Engineering Syllabi

No abstract provided.

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Cs 209: Computer Programming For Business Ii, Dennis Kellermeier Apr 2006

Cs 209: Computer Programming For Business Ii, Dennis Kellermeier

Computer Science & Engineering Syllabi

No abstract provided.

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Cs 240: Introduction To Computer Science I, Praveen Kakumanu Apr 2006

Cs 240: Introduction To Computer Science I, Praveen Kakumanu

Computer Science & Engineering Syllabi

This course is the first in the three course sequence "Introduction to Computer Science" offered by the Computer Science department, WSU. This course presents a general introduction to C++ programming language. It introduces the fundamental capabilities of C++ language as a problem solving tool. Topics include data representation. debugging and program verification. Note: For all CS 24X students, concurrent registration into CS 24X lab is a must.

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Cs 214: Object-Based Programming, Eric Maston Apr 2006

Cs 214: Object-Based Programming, Eric Maston

Computer Science & Engineering Syllabi

This course is a basic introduction to object oriented programming utilizing the Visual Basic programming language.

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Cs 241-01: Computer Science Ii, L. Jane Lin Apr 2006

Cs 241-01: Computer Science Ii, L. Jane Lin

Computer Science & Engineering Syllabi

This course is the second in the three course sequence "Introduction to Computer Science" offered by the Computer Science department, WSU. It focuses on tools for building abstract data types (using structure and class concepts in C++) and Object-Oriented Programming. We also begin the study of data structures in this course. For All CS 241 students, concurrent registration into CS 241 lab is a must.

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Cs 340: Programming Language Workshop In Java, Krishnaprasad Thirunarayan Apr 2006

Cs 340: Programming Language Workshop In Java, Krishnaprasad Thirunarayan

Computer Science & Engineering Syllabi

This course is designed as a self-study in Java. You are expected to learn the Java language and solve a set of programming problems assigned to you using it. (You may develop your code using any IDE you like, but you must ensure that it eventually runs using JDK 5). There are no exams. We officially meet only once in a quarter. However, I will be available in the posted office hours for clarifications and discussions about the programming problems.

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