Physical Sciences and Mathematics Commons^™

Aquatic Plant Surveys In The Bureau Of Land Management, Medford District, 2010-2011, Mark D. Sytsma, Rich Miller, Vanessa Morgan

Center for Lakes and Reservoirs Publications and Presentations

The introduction of invasive aquatic plant species (IAPS) can cause significant ecological and economic harm. IAPS can displace native aquatic plant species, impair recreation, and degrade water quality. Early detection of new invasions can improve chances for successful eradication or containment to reduce the risk of IAPS spread. The Oregon Department of Agriculture (ODA) lists the most egregious offenders as “Noxious Weeds” which are defined as plants classified by the Oregon State Weed Board that are injurious to public health, agriculture, recreation, wildlife, or any public or private property (ODA 2011).

Several IAPS classified as noxious have been detected within …

The Theory And Practice Of Genetically Engineered Crops And Agricultural Sustainability, David E. Ervin, Leland L. Glenna, Raymond Adelard Jussaume

Institute for Sustainable Solutions Publications and Presentations

The development of genetically engineered (GE) crops has focused predominantly on enhancing conventional pest control approaches. Scientific assessments show that these GE crops generally deliver significant economic and some environmental benefits over their conventional crop alternatives. However, emerging evidence indicates that current GE crops will not foster sustainable cropping systems unless the negative environmental and social feedback effects are properly addressed. Moreover, GE crop innovations that promote more sustainable agricultural systems will receive underinvestment by seed and chemical companies that must understandably focus on private returns for major crops. Opportunities to promote crops that convey multi-faceted benefits for the environment …

A Review On Convolutions Of Gamma Random Variables, Baha-Eldin Khaledi, Subhash C. Kochar

Mathematics and Statistics Faculty Publications and Presentations

Due to its wide range of applications, the topic of the distribution theory of convolutions of Gamma random variables has attracted the attention of many researchers. In this paper we review some of the latest developments on this problem.

Reliable A-Posteriori Error Estimators For Hp-Adaptive Finite Element Approximations Of Eigenvalue/Leigenvector Problems, Stefano Giani, Luka Grubisic, Jeffrey S. Ovall

Mathematics and Statistics Faculty Publications and Presentations

We present reliable a-posteriori error estimates for hp-adaptive finite element approxima- tions of eigenvalue/eigenvector problems. Starting from our earlier work on h adaptive finite element approximations we show a way to obtain reliable and efficient a-posteriori estimates in the hp-setting. At the core of our analysis is the reduction of the problem on the analysis of the associated boundary value problem. We start from the analysis of Wohlmuth and Melenk and combine this with our a-posteriori estimation framework to obtain eigenvalue/eigenvector approximation bounds.

Ensemble Methods For Dynamic Data Assimilation Of Chemical Observations In Atmospheric Models, Adrian Sandu, Emil Constantinescu, Gregory R. Carmichael, Tianfeng Chai, Dacian Daescu, John H. Seinfeld

Mathematics and Statistics Faculty Publications and Presentations

The task of providing an optimal analysis of the state of the atmosphere requires the development of dynamic data-driven systems (DDDAS) that efficiently integrate the observational data and the models. Data assimilation, the dynamic incorporation of additional data into an executing application, is an essential DDDAS concept with wide applicability. In this paper we discuss practical aspects of nonlinear ensemble Kalman data assimilation applied to atmospheric chemical transport models. We highlight the challenges encountered in this approach such as filter divergence and spurious corrections, and propose solutions to overcome them, such as background covariance inflation and filter localization. The predictability …

Defining Conservation Priorities For Freshwater Fishes According To Taxonomic, Functional, And Phylogenetic Diversity, Angela L. Strecker, Julian D. Olden, Joanna B. Whittier, Craig Patrick Paukert

Environmental Science and Management Faculty Publications and Presentations

To date, the predominant use of systematic conservation planning has been to evaluate and conserve areas of high terrestrial biodiversity. Although studies in freshwater ecosystems have received recent attention, research has rarely considered the potential trade-offs between protecting different dimensions of biodiversity and the ecological processes that maintain diversity. We provide the first systematic prioritization for freshwaters (focusing on the highly threatened and globally distinct fish fauna of the Lower Colorado River Basin, USA) simultaneously considering scenarios of: taxonomic, functional, and phylogenetic diversity; contemporary threats to biodiversity (including interactions with nonnative species); and future climate change and human population growth. …

Nonlinear Ordinary Differential Equations In Fluid Dynamics, John D. Ramshaw

Physics Faculty Publications and Presentations

The equivalence between nonlinear ordinary differential equations (ODEs) and linear partial differential equations (PDEs) was recently revisited by Smith, who used the equivalence to transform the ODEs of Newtonian dynamics into equivalent PDEs, from which analytical solutions to several simple dynamical problems were derived. We show how this equivalence can be used to derive a variety of exact solutions to the PDEs describing advection in fluid dynamics in terms of solutions to the equivalent ODEs for the trajectories of Lagrangian fluid particles. The PDEs that we consider describe the time evolution of non-diffusive scalars, conserved densities, and Lagrangian surfaces advected …

The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2011, David J. Lauten, Kathleen J. Castelein, J. Daniel Farrar, Adam A. Kotaich, Eleanor P. Gaines

Institute for Natural Resources Publications

From 6 April – 19 September 2011 we monitored the distribution, abundance and productivity of the federally Threatened Western Snowy Plover (Charadrius nivosus nivosus) along the Oregon coast. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Beach, New River, and Floras Lake. Our objectives for the Oregon coastal population in 2011 were to: 1) estimate the size of the adult Snowy Plover population, 2) locate plover nests, 3) continue use of mini-exclosures (MEs) to protect nests from …

Biomimetic Broadband Antireflection Gratings On Solar-Grade Multicrystalline Silicon Wafers, Blayne M. Phillips, Peng Jiang, Bin Jiang

Mathematics and Statistics Faculty Publications and Presentations

The authors report a simple and scalable bottom-up technique for fabricating broadband antireflection gratings on solar-grade multicrystalline silicon (mc-Si) wafers. A Langmuir-Blodgett process is developed to assemble close-packed silica microspheres on rough mc-Si substrates. Subwavelength moth-eye pillars can then be patterned on mc-Si by using the silica microspheres as structural template. Hemispherical reflectance measurements show that the resulting mc-Si gratings exhibit near zero reflection for a wide range of wavelengths. Both experimental results and theoretical prediction using a rigorous coupled-wave analysis model show that close-packed moth-eye arrays exhibit better antireflection performance than non-close-packed arrays due to a smoother refractive index …

2011 Aquatic Weed Surveys In Timothy Lake, Lake Harriet And North Fork Reservoir : Final Report, Mark D. Sytsma, Vanessa Howard Morgan

Center for Lakes and Reservoirs Publications and Presentations

Portland General Electric (PGE) was issued a new license by the Federal Energy Regulatory Commission (FERC) for the continued operation and maintenance of the Clackamas River Hydroelectric Project No. 2195 (Project) on December 21, 2010. This Project is located on both the lower 16 miles of Oak Grove Fork of the Clackamas River (Oak Grove Fork) and the mainstem of the Clackamas River in Clackamas County, Oregon. The effects of relicensing this Project were addressed in the Final Environmental Impact Statement (FEIS) completed in December 2006 and included the issue of invasive aquatic weed species. The term “aquatic weed” is …

Changing The Way We View Humanity And The Rest Of Nature, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

An introduction is presented in which the editor discusses various reports within the issue on topics including the idea of ecosystem services, how ecosystem aided to solve the mother of all problems and how ecosystem services offer real solutions to problems.

A Global Partnership For Ecosystem Services, Dolf De Groot, Robert Costanza, Dieter Van Den Broeck, James Aronson

Institute for Sustainable Solutions Publications and Presentations

The article offers information on the participation of the Baviaanskloof Mega Reserve in the Ecosystem Services Partnership (ESP) in South Africa. It mentions that an active group of scientists has been working with the local and ESP to restore the Mega Reserve using the ecosystem services. The group combines a learning village to raise awareness of the project and a tree nursery that specializes in indigenous species.

Indigenous Australians Fight Climate Change With Fire, Scott Heckbert, Jeremy Russell-Smith, Andrew Reeson, Glenn James

Institute for Sustainable Solutions Publications and Presentations

The article focuses on the move of Indigenous people in Australia to implement fire management in an effort to improve landscape condition and reduce greenhouse gas emissions. It highlights the launch of the West Arnhem Land Fire Abatement (WALFA) project, a prime example of scientists, governments, Indigenous land managers, and carbon markets connecting to offer innovative solutions to resource management and economic development. It also highlights ecosystem services in the region.

Historical Vegetation Of Central Southwest Oregon, Based On Glo Survey Notes : Final Report To Usdi Bureau Of Land Management, Medford District, O. Eugene Hickman, John A. Christy

Institute for Natural Resources Publications

Historical vegetation at the time of European settlement is of great interest to both the public and land managers, but is poorly documented. One source of data are the earliest land survey records of the General Land Office (GLO). Rectangular township surveys in Southwest Oregon were initiated in the mid 1850’s as settlers began to claim homesteads in the Bear Creek Valley surrounding what is now Medford. We examined GLO land survey field notes and plats (maps) accompanying the surveys, transcribed GLO landscape data into an Access database, and classified the data set into very general vegetation types for mapping. …

Frequency Multiplication In Nanowires, Marius Ghita, Ed Godshalk, Gary Goncher, Raj Solanki

Physics Faculty Publications and Presentations

Frequency multiplication in silicon and ZnO nanowire based Schottky and p-n diodes has been demonstrated at fundamental frequencies of 70 MHz and 500 MHz. Our motivation for using nanowires contacted at their tips was to minimize the spreading resistance and boundary capacitance in order to produce higher cut-off frequencies and conversion efficiencies compared to planar diodes. The data presented here are limited to the lower GHz range by the frequency response of the experimental apparatus. However, by employing microwave waveguides and higher fundamental source frequencies, it should be possible to reach much higher output frequencies with nanowire-based diodes.

Dr7a: Changes In Ecosystem Services And Migration In Low-Lying Coastal Areas Over The Next 50 Years, Robert Costanza, Ida Kubiszewski, Joe Roman, Paul Sutton

Institute for Sustainable Solutions Publications and Presentations

This paper examines the history and current status of ecosystem services in low-lying coastal areas (LLCAs), their potential changes because of wider environmental and social shifts, and the potential impacts of these changes on human migration. We synthesised information from a number of sources on the status and value of ecosystem services in LLCAs, including information about key ecosystems that are likely to be particularly vulnerable to environmental change. We created maps of ecosystem and human population changes in LLCAs and then estimated changes in ecosystem services. Estimating the impacts of these potential changes depends on the future scenario one …

Integrating Ecosystem Services, River Restoration And Community: A Case Study At Fisher's Bend, Michael Carlson

Environmental Science and Management Professional Master's Project Reports

Natural areas and ecosystem services at the edge of urban areas are threatened by increasing development. This paper examines how community based restoration partnerships can work to identify, protect and restore ecosystem services provided by salmon and our local rivers. Floodplains provide a wide range of ecosystem services to urban and rural communities and we should work collaboratively to protect and restore them. Floodplains are especially valuable and important for salmon recovery. By using a case study, we explore the process and feasibility of restoring off-channel salmon habitat at Fisher's Bend in the lower Clackamas river. A feasibility study was …

Field Programmable Gate Array Based Reconfigurable Scanning Probe/Optical Microscope, Derek Brant Nowak, Andrew James Lawrence, Zechariah K. Dzegede, Justin C. Hiester, Cliff Kim, Erik J. Sánchez

Physics Faculty Publications and Presentations

The increasing popularity of nanometrology and nanospectroscopy has pushed researchers to develop complex new analytical systems. This paper describes the development of a platform on which to build a microscopy tool that will allow for flexibility of customization to suit research needs. The novelty of the described system lies in its versatility of capabilities. So far, one version of this microscope has allowed for successful near-field and far-field fluorescence imaging with single molecule detection sensitivity. This system is easily adapted for reflection, polarization (Kerr magneto-optical (MO)), Raman, super-resolution techniques, and other novel scanning probe imaging and spectroscopic designs. While collecting …

A Simple Approach To Neutral Atom Microscopy, Philip Witham, Erik J. Sánchez

Physics Faculty Publications and Presentations

Scanning surfaces using a beam of noncharged atoms or molecules allows for especially nondestructive and low-energy surface imaging, with the potential to obtain new information about surfaces that cannot be easily obtained otherwise. We have developed a new approach, operating with the sample at a close working distance from an aperture, the need for optics to focus the beam is obviated. Compared to more complex approaches, the theoretical performance has no other disadvantage than the short working distance. Resolution of 1.5 μm has been achieved, and submicron resolution appears to be practical. Construction of the microscope and results are presented, …

The Influence Of Land Use And Climate Change On Forest Biomass And Composition In Massachusetts, Usa, Jonathan R. Thompson, David R. Foster, Robert M. Scheller, David Kittridge

Environmental Science and Management Faculty Publications and Presentations

Land use and climate change have complex and interacting effects on naturally dynamic forest landscapes. To anticipate and adapt to these changes, it is necessary to understand their individual and aggregate impacts on forest growth and composition. We conducted a simulation experiment to evaluate regional forest change in Massachusetts, USA over the next 50 years (2010–2060). Our objective was to estimate, assuming a linear continuation of recent trends, the relative and interactive influence of continued growth and succession, climate change, forest conversion to developed uses, and timber harvest on live aboveground biomass (AGB) and tree species composition. We examined 20 …

Towards The Rational Design Of Mri Contrast Agents: Δ-Substitution Of Lanthanide(Iii) Nb-Dota-Tetraamide Chelates Influences But Does Not Control Coordination Geometry, Christiane E. Carney, Anh D. Tran, Jing Wang, Matthias C. Schabel, A. Dean Sherry, Mark Woods

Chemistry Faculty Publications and Presentations

LnDOTA-tetraamide chelates (DOTA=1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) have received considerable recent attention as a result of their potential to act as PARACEST contrast agents for magnetic resonance imaging (MRI). Although PARACEST agents afford several advantages over conventional contrast agents they suffer from substantially higher detection limits; thus, improving the effectiveness of LnDOTA-tetraamide chelates is an important goal. In this study we investigate the potential to extend conformational control of LnDOTA-type ligands to those applicable to PARACEST. Furthermore, the question of whether δ- rather than α-substitution of the pendant arms could be used to control the chelate coordination geometry is addressed. Although δ-substitution does …

Properties, Solution State Behavior, And Crystal Structures Of Chelates Of Dotma, Silvio Aime, Mauro Botta, Zoltán Garda, Benjamin E. Kucera, Gyula Tircso, Victor G. Young, Mark Woods

Chemistry Faculty Publications and Presentations

The chemistry of polyamino carboxylates and their use as ligands for Ln(3+) ions is of considerable interest from the point of view of the development of new imaging agents. Of particular interest is the chemistry of the macrocyclic ligand 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) and its derivatives. Herein we report that the tetramethylated DOTA derivative, DOTMA, possess several properties that, from an imaging agent development point of view, are more advantageous than those of the parent DOTA. In particular, the Ln(3+) chelates of DOTMA exhibit a marked preference for the monocapped twisted square antiprismatic coordination isomer which imparts more rapid water exchange …

Whispering-Gallery Acoustic Sensing: Characterization Of Mesoscopic Films And Scanning Probe Microscopy Applications, Andres H. La Rosa, Nan Li, Rodolfo Fernandez, Xiaohua Wang, Richard Nordstrom, S. K. Padigi

Physics Faculty Publications and Presentations

Full understanding of the physics underlying the striking changes in viscoelasticity, relaxation time, and phase transitions that mesoscopic fluid-like films undergo at solid-liquid interfaces, or under confinement between two sliding solid boundaries, constitutes one of the major challenges in condensed matter physics. Their role in the imaging process of solid substrates by scanning probe microscopy (SPM) is also currently controversial. Aiming at improving the reliability and versatility of instrumentation dedicated to characterize mesoscopic films, a noninvasive whispering-gallery acoustic sensing (WGAS) technique is introduced; its application as feedback control in SPM is also demonstrated. To illustrate its working principle and potential …

Thirdhand Tobacco Smoke: Emerging Evidence And Arguments For A Multidisciplinary Research Agenda, Georg E. Matt, Penelope J. Quintana, Hugo Destaillats, Lara A. Gundel, Mohamad Sleiman, Brett C. Singer, Peyton Jacob, Jonathan P. Winickoff, Prue Talbot, Suzaynn Schick, Yinsheng Wang, Bo Hang, Manuela Martins-Green, James F. Pankow, Melbourne F. Hovell, Neal L. Benowitz, Virender K. Rehan, Jonathan M. Samet

Civil and Environmental Engineering Faculty Publications and Presentations

There is broad consensus regarding the health impact of tobacco use and secondhand smoke exposure, yet considerable ambiguity exists about the nature and consequences of thirdhand smoke (THS). We introduce definitions of THS and THS exposure and review recent findings about constituents, indoor sorption-desorption dynamics, and transformations of THS; distribution and persistence of THS in residential settings; implications for pathways of exposure; potential clinical significance and health effects; and behavioral and policy issues that affect and are affected by THS. Physical and chemical transformations of tobacco smoke pollutants take place over time scales ranging from seconds to months and include …

Interview With Jessica Beckett, Free Geek, 2011 (Audio), Jessica Beckett

All Sustainability History Project Oral Histories

Interview of Jessica Beckett by Thomas Yarbrough at Free Geek Portland, Oregon on August 10th, 2011.

The interview index is available for download.

Interview With Christian Ettinger, Hopworks, 2011 (Audio), Christian Ettinger

All Sustainability History Project Oral Histories

Interview of Christian Ettinger by Scott Demming at Hopworks SE Portland, Oregon on August 10th, 2011.

The interview index is available for download.

Interview With Weston Miller, Osu Extension Service, 2011 (Audio), Weston Miller

All Sustainability History Project Oral Histories

Interview of Weston Miller by Jan Steinbock in Portland, Oregon on August 3rd, 2011.

The interview index is available for download.

Interview With Trudy Toliver, Portland Farmers Market, 2011 (Audio), Trudy Toliver

All Sustainability History Project Oral Histories

Interview of Trudy Toliver by Sara Davenport at Portland, Oregon on August 1st, 2011.

The interview index is available for download.

Determination Of The Electric Field Intensity And Space Charge Density Versus Height Prior To Triggered Lightning, Christopher J. Biagi, Martin A. Uman, Jay Gopalakrishnan, J. D. Hill, Vladimir A. Rakov, T. Ngin, Douglas M. Jordan

Mathematics and Statistics Faculty Publications and Presentations

We infer the vertical profiles of space charge density and electric field intensity above ground by comparing modeling and measurements of the ground-level electric field changes caused by elevating grounded lightning-triggering wires. The ground-level electric fields at distances of 60 m and 350 m were measured during six wire launches that resulted in triggered lightning. The wires were launched when ground-level electric fields ranged from 3.2 to 7.6 kV m⁻¹ and the triggering heights ranged from 123 to 304 m. From wire launch time to lightning initiation time, the ground-level electric field reduction at 60 m ranged from 2.2 …

Quantifying 20th Century Glacier Change In The Sierra Nevada, California, Andrew G. Fountain, Hassan J. Basagic

Geology Faculty Publications and Presentations

Numerous small alpine glaciers occupy the high elevation regions of the central and southern Sierra Nevada, California. An inventory based on 1:24,000 topographic maps revealed 1719 glaciers and perennial snowfields for a total area of 39.15 +/- 0.13 km(2). The number of 'true' glaciers, versus non-moving ice, is estimated to be 122 covering 14.89 +/- 0.08 km(2) or 38% of the ice-covered area. Historic photographs, geologic evidence, and field mapping were used to determine the magnitude of area change over the past century at 14 glaciers. The area change between 1903 and 2004 ranged from -31% to -78%, averaging -55%. …