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Flocks And Formations, J. J. P. Veerman, Gerardo Lafferriere, John S. Caughman Iv, A. Williams Jan 2005

Flocks And Formations, J. J. P. Veerman, Gerardo Lafferriere, John S. Caughman Iv, A. Williams

Mathematics and Statistics Faculty Publications and Presentations

Given a large number (the “flock”) of moving physical objects, we investigate physically reasonable mechanisms of influencing their orbits in such a way that they move along a prescribed course and in a prescribed and fixed configuration (or “in formation”). Each agent is programmed to see the position and velocity of a certain number of others. This flow of information from one agent to another defines a fixed directed (loopless) graph in which the agents are represented by the vertices. This graph is called the communication graph. To be able to fly in formation, an agent tries to match the …

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Realizing Ternary Quantum Switching Networks Without Ancilla Bits, Marek Perkowski, Guowu Yang, Xiaoyu Song, Jinzhao Wu Jan 2005

Realizing Ternary Quantum Switching Networks Without Ancilla Bits, Marek Perkowski, Guowu Yang, Xiaoyu Song, Jinzhao Wu

Electrical and Computer Engineering Faculty Publications and Presentations

This paper investigates the synthesis of quantum networks built to realize ternary switching circuits in the absence of ancilla bits. The results we established are twofold. The first shows that ternary Swap, ternary NOT and ternary Toffoli gates are universal for the realization of arbitrary n × n ternary quantum switching networks without ancilla bits. The second result proves that all n×n quantum ternary networks can be generated by NOT, Controlled-NOT, Multiply-Two and Toffoli gates. Our approach is constructive.

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Biotic Resistance To Invasion: Native Predator Limits Abundance And Distribution Of An Introduced Crab, Catherine E. De Rivera, Greg M. Ruiz, Anson Hines, Paul Jivoff Jan 2005

Biotic Resistance To Invasion: Native Predator Limits Abundance And Distribution Of An Introduced Crab, Catherine E. De Rivera, Greg M. Ruiz, Anson Hines, Paul Jivoff

Environmental Science and Management Faculty Publications and Presentations

Introduced species frequently escape the natural enemies (predators, competitors, and parasites) that limit their distribution and abundance in the native range. This reduction in native predators, competitors, and parasites may result in ecological release in the introduced range. However, biological interactions also can limit the establishment and spread of nonnative populations. The extent to which such biotic resistance occurs is poorly resolved, especially for marine ecosystems. Here we test whether a native predator, the blue crab Callinectes sapidus, affects the abundance and geographic range of the introduced European green crab Carcinus maenas in eastern North America. Both crab species …

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Broad-Scale Non-Indigenous Species Monitoring Along The West Coast In National Marine Sanctuaries And National Estuarine Research Reserves, Catherine E. De Rivera, Greg Ruiz, Jeff Crooks, Kerstin Wasson, Steve Lonhart, Paul Fofonoff, Brian Steves, Steven S. Rumrill, Mary Sue Brancato, Scott Pegau, Doug Bulthuis, Rikke Kvist Preisler, Carl Schoch, Ed Bowlby, Andrew Devogelaere, Maurice Crawford, Steve Gittings, Anson Hines, Lynn Takata, Kristen Larson, Tami Huber, Anne Marie Leyman, Esther Collinetti, Tiffany Pascot, Suzanne Shull, Mary Anderson, Sue Powell Jan 2005

Broad-Scale Non-Indigenous Species Monitoring Along The West Coast In National Marine Sanctuaries And National Estuarine Research Reserves, Catherine E. De Rivera, Greg Ruiz, Jeff Crooks, Kerstin Wasson, Steve Lonhart, Paul Fofonoff, Brian Steves, Steven S. Rumrill, Mary Sue Brancato, Scott Pegau, Doug Bulthuis, Rikke Kvist Preisler, Carl Schoch, Ed Bowlby, Andrew Devogelaere, Maurice Crawford, Steve Gittings, Anson Hines, Lynn Takata, Kristen Larson, Tami Huber, Anne Marie Leyman, Esther Collinetti, Tiffany Pascot, Suzanne Shull, Mary Anderson, Sue Powell

Environmental Science and Management Faculty Publications and Presentations

Nonindigenous species have caused substantial environmental and economic damage to coastal areas. Moreover, the extent and impacts of nonindigenous species are increasing over time. To develop predictive models and to identify which areas should be targeted for impact mitigation or early detection, we need a basic foundation of knowledge about the spatial and temporal patterns of invasions. This project was developed because we lacked the necessary data to rigorously evaluate the patterns of coastal invasions. This collaborative project, between the Smithsonian Environmental Research Center, the National Estuarine Research Reserve System (NERRS) and the National Marine Sanctuary Program (NMSP), established a …

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Response Of Sagebrush Steppe Species To Elevated Co2 And Soil Temperature, Melissa S. Lucash, Blake Farnsworth, William E. Winner Jan 2005

Response Of Sagebrush Steppe Species To Elevated Co2 And Soil Temperature, Melissa S. Lucash, Blake Farnsworth, William E. Winner

Environmental Science and Management Faculty Publications and Presentations

Elevated atmospheric CO2 may cause long-term changes in the productivity and species composition of the sagebrush steppe. Few studies, however, have evaluated the effects of increased CO2 on growth and physiology of species important to this ecosystem. Since the response of plants to elevated CO2 may be limited by environmental factors, soil temperature was also examined to determine if low soil temperatures limit CO2 response. To determine how CO2 and soil temperature affect the growth of species native to the sagebrush steppe, bottlebrush squirreltail [Elymus elymoides (Raf.) Swezey], Thurber needlegrass (Stipa thurberiana Piper), …

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Temporal Variation In Nutrient Uptake Capacity By Intact Roots Of Mature Loblolly Pine, Melissa S. Lucash, J. Devereux Joslin, Ruth D. Yanai Jan 2005

Temporal Variation In Nutrient Uptake Capacity By Intact Roots Of Mature Loblolly Pine, Melissa S. Lucash, J. Devereux Joslin, Ruth D. Yanai

Environmental Science and Management Faculty Publications and Presentations

Nutrient uptake is generally thought to exhibit a simple seasonal pattern, but few studies have measured temporal variation of nutrient uptake capacity in mature trees. We measured net uptake capacity of K, NH+ 4, NO 3 −, Mg and Ca across a range of solution concentrations by roots of mature loblolly pine at Calhoun Experimental Forest in October 2001, July 2001, and April 2002. Uptake capacity was generally lowest in July; rates in October were similar to those in April. Across a range of concentrations, antecedent nutrient solution concentrations affected the temporal patterns in uptake in July but not in …

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Depth-Shifting Of Shallow Water Guide Source Observations, Lisa M. Zurk, Brian H. Tracey Jan 2005

Depth-Shifting Of Shallow Water Guide Source Observations, Lisa M. Zurk, Brian H. Tracey

Electrical and Computer Engineering Faculty Publications and Presentations

In theory, matched field processing offers the significant benefit of higher signal gains and increased localization capability. However, this has not been robustly observed in practice because of inherent uncertainties about details of the shallow water propagation environments which limit the prediction of the channel response. The use of guide sources to directly measure the transfer function between source and receiver arrays has been proposed as a means for reducing mismatch. However, the guide source measurement only provides a measured transfer function at the guide source location. In this paper a method of depth-shifting guide source observations is proposed, making …

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What Does The Term "High Quality" Mathematics Teacher Mean?, David M. Davison Jan 2005

What Does The Term "High Quality" Mathematics Teacher Mean?, David M. Davison

Northwest Journal of Teacher Education

The term "highly qualified teacher" occurs frequently in discussions on educational issues today, but there is no agreement about the meaning of this term. There is agreement that "teacher quality" should be expected of our teachers, but this term also lacks precise definition. Some educators believe that mastery of content knowledge is not only important, but is all that is important. Others suggest that failure to recognize the importance of teaching skills limits the definition of teacher quality. Nevertheless, most educators agree that student achievement is the necessary outcome and that teaching strategies must conform to this outcome. Future research …

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Ancient Chinese Secret: Washington Assessment Of Student Learning (Wasl) Tests And High Stakes Tests In China, Jane Liu, Rita Seedorf Jan 2005

Ancient Chinese Secret: Washington Assessment Of Student Learning (Wasl) Tests And High Stakes Tests In China, Jane Liu, Rita Seedorf

Northwest Journal of Teacher Education

A comparison of the testing movements in China and Washington State reveals a strange irony. While education in Washington, under State and National imperatives, is becoming test driven, China is trying to move away from 14 centuries of test driven education to promote the development of the student as an entire person. This article compares and contrasts the Washington Assessment of Student Learning Tests and fourth and seventh grade examinations used in Baoding, China in terms of content, administration, evolution, and curriculum standards guiding the test content. Curriculum Guides and Assessment Manuals are compared. The historical practice of high stakes …

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Incompressible Finite Elements Via Hybridization. Part I: The Stokes System In Two Space Dimensions, Bernardo Cockburn, Jay Gopalakrishnan Jan 2005

Incompressible Finite Elements Via Hybridization. Part I: The Stokes System In Two Space Dimensions, Bernardo Cockburn, Jay Gopalakrishnan

Mathematics and Statistics Faculty Publications and Presentations

In this paper, we introduce a new and efficient way to compute exactly divergence-free velocity approximations for the Stokes equations in two space dimensions. We begin by considering a mixed method that provides an exactly divergence-free approximation of the velocity and a continuous approximation of the vorticity. We then rewrite this method solely in terms of the tangential fluid velocity and the pressure on mesh edges by means of a new hybridization technique. This novel formulation bypasses the difficult task of constructing an exactly divergence-free basis for velocity approximations. Moreover, the discrete system resulting from our method has fewer degrees …

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Nédélec Spaces In Affine Coordinates, Jay Gopalakrishnan, Luis E. García-Castillo, Leszek Demkowicz Jan 2005

Nédélec Spaces In Affine Coordinates, Jay Gopalakrishnan, Luis E. García-Castillo, Leszek Demkowicz

Mathematics and Statistics Faculty Publications and Presentations

In this note, we provide a conveniently implementable basis for simplicial Nédélec spaces of any order in any space dimension. The main feature of the basis is that it is expressed solely in terms of the barycentric coordinates of the simplex.

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Curvature Of The Weinhold Metric For Thermodynamical Systems With 2 Degrees Of Freedom, Manuel Santoro, Serge Preston Jan 2005

Curvature Of The Weinhold Metric For Thermodynamical Systems With 2 Degrees Of Freedom, Manuel Santoro, Serge Preston

Mathematics and Statistics Faculty Publications and Presentations

In this work the curvature of Weinhold (thermodynamical) metric is studied in the case of systems with two thermodynamical degrees of freedom. Conditions for the Gauss curvature R to be zero, positive or negative are worked out. Signature change of the Weinhold metric and the corresponding singular behavior of the curvature at the phase boundaries are studied. Cases of systems with the constant Cv, including Ideal and Van der Waals gases, and that of Berthelot gas are discussed in detail.

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Modeling The Evolution Of Inhomogeneities, Marek Elźanowski, Serge Preston Jan 2005

Modeling The Evolution Of Inhomogeneities, Marek Elźanowski, Serge Preston

Mathematics and Statistics Faculty Publications and Presentations

A model of an anelastic evolution law of a defective continuum is discussed, emphasizing the role of the Clausius-Duhem inequality in selecting admissible processes.

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Rcu Semantics: A First Attempt, Paul E. Mckenney, Jonathan Walpole Jan 2005

Rcu Semantics: A First Attempt, Paul E. Mckenney, Jonathan Walpole

Computer Science Faculty Publications and Presentations

There is not yet a formal statement of RCU (read-copy update) semantics. While this lack has thus far not been an impediment to adoption and use of RCU, it is quite possible that formal semantics would point the way towards tools that automatically validate uses of RCU or that permit RCU algorithms to be automatically generated by a parallel compiler. This paper is a first attempt to supply a formal definition of RCU. Or at least a semi-formal definition: although RCU does not yet wear a tux (though it does run in Linux), at least it might yet wear some …

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Synthesis Of Ternary Quantum Logic Circuits By Decomposition, Marek Perkowski Jan 2005

Synthesis Of Ternary Quantum Logic Circuits By Decomposition, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

Recent research in multi-valued logic for quantum computing has shown practical advantages for scaling up a quantum computer. [1,12] Multivalued quantum systems have also been used in the framework of quantum cryptography, [4] and the concept of a qudit cluster state has been proposed by generalizing the qubit cluster state. [5] An evolutionary algorithm based synthesizer for ternary quantum circuits has recently been presented, [2] as well as a synthesis method based on matrix factorization [3].In this paper, a recursive synthesis method for ternary quantum circuits based on the Cosine-Sine unitary matrix decomposition is presented.

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A Note On Lattice Chains And Delannoy Numbers, John S. Caughman Iv, Clifford R. Haithcock, J. J. P. Veerman Jan 2005

A Note On Lattice Chains And Delannoy Numbers, John S. Caughman Iv, Clifford R. Haithcock, J. J. P. Veerman

Mathematics and Statistics Faculty Publications and Presentations

Fix nonnegative integers n1,…,nd and let L denote the lattice of integer points (a1,…,ad)∈Zd satisfying 0⩽ai⩽ni for 1⩽i⩽d. Let L be partially ordered by the usual dominance ordering. In this paper we offer combinatorial derivations of a number of results concerning chains in L. In particular, the results obtained are established without recourse to generating functions or recurrence relations. We begin with an elementary derivation of the number of chains in L of a given size, from which one can deduce the classical expression for the total number …

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The Reno Aerosol Optics Study: An Evaluation Of Aerosol Absorption Measurement Methods, Patrick J. Sheridan, W. Patrick Arnott, John A. Ogren, Elisabeth Andrews, Dean B. Atkinson, David S. Covert, Hans Moosmüller, Andreas Petzold, Beat Schmid, Anthony W. Strawa, Ravi Varma, Aki Virkkula Jan 2005

The Reno Aerosol Optics Study: An Evaluation Of Aerosol Absorption Measurement Methods, Patrick J. Sheridan, W. Patrick Arnott, John A. Ogren, Elisabeth Andrews, Dean B. Atkinson, David S. Covert, Hans Moosmüller, Andreas Petzold, Beat Schmid, Anthony W. Strawa, Ravi Varma, Aki Virkkula

Chemistry Faculty Publications and Presentations

The Reno Aerosol Optics Study (RAOS) was designed and conducted to compare the performance of many existing and new instruments for the in situ measurement of aerosol optical properties with a focus on the determination of aerosol light absorption. For this study, simple test aerosols of black and white particles were generated and combined in external mixtures under low relative humidity conditions and delivered to each measurement system. The aerosol mixing and delivery system was constantly monitored using particle counters and nephelometers to ensure that the same aerosol number concentration and amount reached the different instruments. The aerosol light-scattering measurements …

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“Judith” Shakespeare In Computer Programming : An Oral History Study Of American Women Programmers In The Late Twentieth Century, Laura L. Zeigen Jan 2005

“Judith” Shakespeare In Computer Programming : An Oral History Study Of American Women Programmers In The Late Twentieth Century, Laura L. Zeigen

Dissertations and Theses

The question "Why are there not more women in computer science?" is one that has been asked by both scholarly and business communities since women entered the workforce in large numbers starting in the 1970s. Although there exists a vast literature covering how to involve more girls and women in computer science today, as well as a smaller body of literature outlining the few female pioneers in the field, little has been written about the women who, despite historical exclusion, actually participated in the computing industry as programmers and software engineers beginning in the 1960s. Who were the women going …

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Marine Ice Modification Of Fringing Ice Shelf Flow, Christina L. Hulbe, R. Johnston, Ian R. Joughin, Ted A. Scambos Jan 2005

Marine Ice Modification Of Fringing Ice Shelf Flow, Christina L. Hulbe, R. Johnston, Ian R. Joughin, Ted A. Scambos

Geology Faculty Publications and Presentations

Locally derived ice is often observed to fill through-cutting rifts and uneven fronts in ice shelves. That ice may nucleate as fast ice at the shelf front, by growth at the sea surface within rifts, or by basal accretion. Here, we investigate the role of such ice in the flow of the Brunt Ice Shelf and adjacent Stancomb-Wills ice tongue, along the Caird Coast of Antarctica. Much of the shelf system is severely rifted, with locally derived ice filling the space between rift walls and around ice rafts. A series of numerical experiments that account for thermal properties of the …

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Locality, Network Control And Anomaly Detection, Jim Binkley Jan 2005

Locality, Network Control And Anomaly Detection, Jim Binkley

Computer Science Faculty Publications and Presentations

Ourmon is a near real-time network monitoring and anomaly detection system that captures packets using port-mirroring on Ethernet switches. It primarily displays data via web graphics using either RRDTOOL stripcharts or via histograms for top talker style graphs. We have developed a theory that network scanning launched primarily by worm programs including TCP and UDP scanners may be caught by monitoring network control data including TCP control packets (SYNS, FINS, RESETS) and ICMP errors, or by monitoring certain carefully chosen metadata such as the flow count itself. In this paper we concentrate on TCP and present a ”flow tuple” focused …

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Vertical Nanowire Light-Emitting Diode, Rolf Könenkamp, Robert Campbell Word, C. Schlegel Dec 2004

Vertical Nanowire Light-Emitting Diode, Rolf Könenkamp, Robert Campbell Word, C. Schlegel

Physics Faculty Publications and Presentations

We report room-temperature, white-color electroluminescence in vertically oriented ZnO nanowires. Excitonic luminescence around 380 nm is observed as a shoulder on a broader defect-related band covering all of the visible range and centered at 620 nm. The ZnO nanowires are grown in a low-temperature process on SnO2-coated glass substrates, employing a technique that is suitable for large-area applications. The nanowires are robustly encapsulated in a thin polystyrene film deposited from high-molecular-weight solutions. Electron injection occurs through the transparent SnO2 layer, while hole injection is mediated by a p-doped polymer and an evaporated Au contact. Stable device operation …

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The Meyer-Neldel Rule For Diodes In Forward Bias, Ralf Widenhorn, Michael Fitzgibbons, Erik Bodegom Dec 2004

The Meyer-Neldel Rule For Diodes In Forward Bias, Ralf Widenhorn, Michael Fitzgibbons, Erik Bodegom

Physics Faculty Publications and Presentations

We analyzed the temperature dependence of the forward current of a silicon diode. Instead of representing the data in the ordinarily used current versus voltage graph, the currents are plotted for different voltages as a function of the inverse temperature. The constant voltage curves can be fitted linearly and the extrapolations of the fits seem to merge to one common focal point. Hence, we demonstrate that a real diode follows the Meyer-Neldel rule (MNR). It is shown that the MNR is due to a shift of the current from ideal-diode to high-injection-diode behavior. We will argue that the merging of …

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Toward The Design Of Mr Agents For Imaging Β-Cell Function, Mark Woods, Shanrong Zhang, A. Dean Sherry Dec 2004

Toward The Design Of Mr Agents For Imaging Β-Cell Function, Mark Woods, Shanrong Zhang, A. Dean Sherry

Chemistry Faculty Publications and Presentations

The chemistry of Gd3+-based MRI agents has advanced considerably during the past decade toward agents with higher relaxivity and agents that respond to physiology and / or metabolism. This review describes various approaches that have been taken toward the development of responsive contrast agents and discusses the importance of fast water exchange for advancement of targeted Gd3+-based agents with higher sensitivity. The recent discovery of Eu3+ complexes having extraordinarily slow water exchange has opened a new avenue in contrast agent design based upon the chemical exchange saturation transfer (CEST) mechanism. These new paramagnetic complexes called PARACEST agents offer new possibilities …

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Lower Columbia River Aquatic Nonindigenous Species Survey 2001-2004, Mark Sytsma, Jeffery Cordell, John Chapman, Robyn Draheim Oct 2004

Lower Columbia River Aquatic Nonindigenous Species Survey 2001-2004, Mark Sytsma, Jeffery Cordell, John Chapman, Robyn Draheim

Center for Lakes and Reservoirs Publications and Presentations

Rates of aquatic nonindigenous species (ANS) introductions and their social, economic, and ecological impacts are increasing. Introductions of nonnative marine organisms have increased exponentially over the last two centuries and expenditures on outreach, control, and research exceed millions of dollars per species for several invaders of particular concern to the United States. These trends suggest that major changes are occurring in the freshwater, estuarine, and marine ecosystems of North America, but their magnitude is probably underestimated.

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Report On The Oregon Ballast Water Management Program In 2004, Kiirsten Flynn, Mark Sytsma Sep 2004

Report On The Oregon Ballast Water Management Program In 2004, Kiirsten Flynn, Mark Sytsma

Center for Lakes and Reservoirs Publications and Presentations

This report was prepared for the Oregon legislature pursuant to HB 3620, which was passed during the 2003 session of the Oregon legislature to address management of ballast water discharged from ships. The bill removed sediment from the definition of ballast water, allowed discharge of treated ballast water, created a task force on ballast water management, and required this report. Includes List of Acronyms, charts, graphs and maps.

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Vertical Nanowire Transistors With Low Leakage Current, Jie Chen, M. C. Lux-Steiner, Rolf Kӧnenkamp, S. Klaumünzer Aug 2004

Vertical Nanowire Transistors With Low Leakage Current, Jie Chen, M. C. Lux-Steiner, Rolf Kӧnenkamp, S. Klaumünzer

Physics Faculty Publications and Presentations

A vertical field-effect transistor based on semiconductor nanowires is reported. The fabrication of the device uses a self-supporting flexible nanostructured polymer foil as a template and an electrochemical growth technique for the preparation of the semiconductor. The fabrication process is substantially simpler, and the mechanical robustness is strongly increased as compared to the original device. The channel region of the transistor has a diameter of ∼100 nm and a length of ∼50 nm. Operation in the hole depletion mode allows a change of the transfer conductance by ∼50% when the gate voltages is changed in the range ∓1 V. The …

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Synthesis, Relaxometric And Photophysical Properties Of A New Ph-Responsive Mri Contrast Agent: The Effect Of Other Ligating Groups On Dissociation Of A P-Nitrophenolic Pendant Arm, Mark Woods, Garry Kiefer, Simon G. Bott, Aminta Castillo-Muzquiz, Carrie Eshelbrenner, Lydie Michaudet, Kenneth Mcmillan, Siva D.K. Mudigunda, Doug Ogrin, Gyula Tircso, Shanrong Zhang, Piyu Zhao, A. Dean Sherry Aug 2004

Synthesis, Relaxometric And Photophysical Properties Of A New Ph-Responsive Mri Contrast Agent: The Effect Of Other Ligating Groups On Dissociation Of A P-Nitrophenolic Pendant Arm, Mark Woods, Garry Kiefer, Simon G. Bott, Aminta Castillo-Muzquiz, Carrie Eshelbrenner, Lydie Michaudet, Kenneth Mcmillan, Siva D.K. Mudigunda, Doug Ogrin, Gyula Tircso, Shanrong Zhang, Piyu Zhao, A. Dean Sherry

Chemistry Faculty Publications and Presentations

Two gadolinium(III) chelates, GdNP-DO3A (1-methlyene-(p-NitroPhenol)-1,4,7,10-tetraazacycloDOdecane-4,7,10-triAcetate) and GdNP-DO3AM (1-methlyene(p-NitroPhenol)-1,4,7,10-tetraazacycloDOdecane-4,7,10-triacetAMide), containing a single nitrophenolic pendant arm plus either three acetate or three amide pendant arms were synthesized and characterized. The properties of the gadolinium, terbium, and dysprosium complexes of these ligands were examined as a function of pH. The extent and mechanism of the changes in water relaxivity with pH of each gadolinium complex was found to differ substantially for the two complexes. The water relaxivity of Gd(NP-DO3A) increases from 4.1 …

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Willamette River Basin Temperature Tmdl Model: Model Calibration, Chris Berger, Michael Lee Mckillip, Robert Leslie Annear, Sher Jamal Khan, Scott A. Wells Aug 2004

Willamette River Basin Temperature Tmdl Model: Model Calibration, Chris Berger, Michael Lee Mckillip, Robert Leslie Annear, Sher Jamal Khan, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The State of Oregon Department of Environmental Quality (DEQ) is developing a TMDL for temperature in the Willamette River basin shown in Figure 1. The study area included the Willamette River and all major tributaries (except the Tualatin River where a TMDL process was already concluded). A large section of the Columbia River was also modeled to provide adequate boundary representation of tidal flows in the lower Willamette River. The Willamette River below the Oregon City Falls in the Portland metropolitan area has a typical diurnal tidal range of 1 m. The development of a dynamic model of temperature and …

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Enhancements To Crisp Possibilistic Reconstructability Analysis, Anas Al-Rabadi, Martin Zwick Aug 2004

Enhancements To Crisp Possibilistic Reconstructability Analysis, Anas Al-Rabadi, Martin Zwick

Complex Systems Faculty Publications and Presentations

Modified Reconstructibility Analysis (MRA), a novel decomposition within the framework of set-theoretic (crisp possibilistic) Reconstructibility Analysis, is presented. It is shown that in some cases while 3-variable NPN-classified Boolean functions are not decomposable using Conventional Reconstructibility Analysis (CRA), they are decomposable using Modified Reconstructibility Analysis (MRA). Also, it is shown that whenever a decomposition of 3-variable NPN-classified Boolean functions exists in both MRA and CRA, MRA yields simpler or equal complexity decompositions. A comparison of the corresponding complexities for Ashenhurst-Curtis decompositions, and Modified Reconstructibility Analysis (MRA) is also presented. While both AC and MRA decompose some but …

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The Kin Composition Of Social Groups: Trading Group Size For Degree Of Altruism, Leticia Avilés, Jeffrey Alan Fletcher, Asher D. Cutter Jul 2004

The Kin Composition Of Social Groups: Trading Group Size For Degree Of Altruism, Leticia Avilés, Jeffrey Alan Fletcher, Asher D. Cutter

Complex Systems Faculty Publications and Presentations

Why some social systems form groups composed of kin, while others do not, has gone largely untreated in the literature. Using an individual-based simulation model, we explore the demographic consequences of making kinship a criterion in group formation. We find that systems where social groups consist of one generation breeding associations may face a serious trade-off between degree of altruism and group size that is largely mediated by their kin composition. On the one hand, restricting groups to close kin allows the evolution of highly altruistic behaviors but may limit group size to suboptimal levels, the more severely so the …

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