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Creating A Learning Continuum: A Critical Look At The Intersection Of Prior Knowledge, Outdoor Education, And Next Generation Science Standards Disciplinary Core Ideas And Practices, Trisha Leigh Schlobohm

Dissertations and Theses

Outdoor School is a cherished educational tradition in the Portland, OR region. This program's success is attributed to its presumed ability to positively impact affective and cognitive student outcomes. Residential programs such as Outdoor School are considered to be an important supplement to the classroom model of learning because they offer an authentic, contextually rich learning environment. References to relevant literature support the idea that student gains in affective and cognitive domains occur as a result of the multi-sensory, enjoyable, hands-on nature of outdoor learning. The sample population for this study was 115 sixth graders from a demographically diverse Portland, …

The Differing Biogeochemical And Microbial Signatures Of Glaciers And Rock Glaciers, Timothy S. Fegel, Jill S. Baron, Andrew G. Fountain, Gunnar F. Johnson, Ed K. Hall

Geology Faculty Publications and Presentations

Glaciers and rock glaciers supply water and bioavailable nutrients to headwater mountain lakes and streams across all regions of the American West. Here we present a comparative study of the metal, nutrient, and microbial characteristics of glacial and rock glacial influence on headwater ecosystems in three mountain ranges of the contiguous U.S.: the Cascade Mountains, Rocky Mountains, and Sierra Nevada. Several meltwater characteristics (water temperature, conductivity, pH, metals, nutrients, complexity of dissolved organic matter (DOM), and bacterial richness and diversity) differed significantly between glacier and rock glacier meltwaters, while other characteristics (Ca²+, Fe³+, SiO₂ concentrations, …

A Novel Methodology For Spatial Damage Detection And Imaging Using A Distributed Carbon Nanotube-Based Composite Sensor Combined With Electrical Impedance Tomography, Hongbo Dai, Gerard J. Gallo, Thomas Schumacher, Erik T. Thostenson

Civil and Environmental Engineering Faculty Publications and Presentations

This paper describes a novel non-destructive evaluation methodology for imaging of damage in composite materials using the electrical impedance tomography (EIT) technique applied to a distributed carbon nanotube-based sensor. The sensor consists of a nonwoven aramid fabric, which was first coated with nanotubes using a solution casting approach and then infused with epoxy resin through the vacuum assisted resin transfer molding technique. Finally, this composite sensor is cured to become a mechanically-robust, electromechanically-sensitive, and highly customizable distributed two-dimensional sensor which can be adhered to virtually any substrate. By assuming that damage on the sensor directly affects its conductivity, a difference …

Information Representation And Computation Of Spike Trains In Reservoir Computing Systems With Spiking Neurons And Analog Neurons, Amin Almassian

Dissertations and Theses

Real-time processing of space-and-time-variant signals is imperative for perception and real-world problem-solving. In the brain, spatio-temporal stimuli are converted into spike trains by sensory neurons and projected to the neurons in subcortical and cortical layers for further processing.

Reservoir Computing (RC) is a neural computation paradigm that is inspired by cortical Neural Networks (NN). It is promising for real-time, on-line computation of spatio-temporal signals. An RC system incorporates a Recurrent Neural Network (RNN) called reservoir, the state of which is changed by a trajectory of perturbations caused by a spatio-temporal input sequence. A trained, non- recurrent, linear readout-layer interprets the …

Consistency Analysis For Judgment Quantification In Hierarchical Decision Model, Mustafa Sulaiman Abbas

Dissertations and Theses

The objective of this research is to establish consistency thresholds linked to alpha (α) levels for HDM’s (Hierarchical Decision Model) judgment quantification method. Measuring consistency in order to control it is a crucial and inseparable part of any AHP/HDM experiment. The researchers on the subject recommend establishing thresholds that are statistically based on hypothesis testing, and are linked to the number of decision variables and (α) level. Such thresholds provide the means with which to evaluate the soundness and validity of an AHP/HDM decision. The linkage of thresholds to (α) levels allows the decision makers to set an appropriate inconsistency …

The Biomolecule Sequencer Project: Nanopore Sequencing As A Dual-Use Technology For Crew Health And Astrobiology Investigations, K. K. John, D. S. Botkin, A. S. Burton, S. L. Castro-Wallace, J. D. Chaput, J. P. Dworkin, Niles Lehman, M. L. Lupisella, C. E. Mason, D. J. Smith, S. Stahl, C. Switzer

Chemistry Faculty Publications and Presentations

Human missions to Mars will fundamentally transform how the planet is explored, enabling new scientific discoveries through more sophisticated sample acquisition and processing than can currently be implemented in robotic exploration. The presence of humans also poses new challenges, including ensuring astronaut safety and health and monitoring contamination. Because the capability to transfer materials to Earth will be extremely limited, there is a strong need for in situ diagnostic capabilities. Nucleotide sequencing is a particularly powerful tool because it can be used to: (1) mitigate microbial risks to crew by allowing identification of microbes in water, in air, and on …

Finding The Missing Links: A Comparison Of Social Network Analysis Methods, Shawn James Mehess

Dissertations and Theses

Too many students leave school without even the essential skills (ACT, 2011), and many others are so drained by the experience they lack a desire to continue on to a post-secondary education. Academic engagement has emerged as a construct representing students’ personal investment in school (Greenwood, Delquadri, & Hall, 1984), and may be a psychological variable which can be intervened on. However, interventions must occur as quickly as possible to maximize their efficiency (Heckman, 2007). Students’ peer groups may be a particularly potent venue of intervention, however several options exist for how to go about measuring their social networks.

In …

Growing Stem Education On The Playground: A Case Study Of The Factors That Influence Teachers’ Use Of School Gardens, Megan Poole

Dissertations and Theses

School gardens can have a profound, positive influence on a student's academic achievement, social skills, and attitudinal orientation. Despite these clear benefits, the use of school gardens as an instructional medium is not as prevalent as would be expected. There are several types of obstacles that can prevent teachers from using school gardens, including facets of time, support, and knowledge-based challenges. This multiple case study employs a mixed methods design to uncover factors that influence primary school teachers' decisions to utilize a school garden in their STEM curriculum. The goals of this study were to determine the types of benefits …

Learning Through Nature: A Study Of A Next Generation Science Standards Based Teacher Workshop That Blends Outdoor Learning Experiences With Formal Science, Ashley Fanning

Dissertations and Theses

Many teachers lack the confidence and knowledge to transition their classroom science lessons to an outdoor setting. Very few teacher professional development (PD) programs focus on improving teachers' self-efficacy and pedagogical content knowledge (PCK) that is needed to enhance their science curriculum with outdoor lessons. This study examined an exception: The Connect2Science workshops, which provided elementary teachers the opportunity to experience nature-based science lessons. My research question for this study is: In what ways does a professional development workshop focused around the Next Generation Science Standards influence teachers': a) self-efficacy in teaching science outdoors and b) science pedagogical content knowledge? …

Tryon Trekkers: An Evaluation Of A Stem Based Afterschool Program For At-Risk Youth, Chessa Eckels Anderson

Dissertations and Theses

This study contributed to the body of research that supports a holistic model of afterschool learning through the design of an afterschool intervention that benefits elementary school students of low socioeconomic status. This qualitative study evaluated a science focused afterschool curriculum that was designed using principles from Risk and Resiliency Theory, academic motivation theories, science core ideas from the Next Generation Science Standards, and used environmental education philosophy. The research question of this study is: how does an outdoor and STEM based afterschool program impact at-risk students' self-efficacy, belonging and engagement and ability to apply conceptual knowledge of environmental science …

Acid-Base Equilibria In Organic-Solvent/Water Mixtures And Their Relevance To Gas/Particle Partitioning In The Atmosphere And In Tobacco Smoke, Julia Lynn Degagne

Dissertations and Theses

Acid-base equilibria in organic particulate matter (PM) are poorly understood, but have important implications for air quality and public health. First, acid-base reactions in organic particulate matter affect the gas/particle partitioning of organic compounds in the atmosphere, and these processes are not currently represented in atmospheric and climate change models. Second, the acid-base balance of tobacco smoke affects the amount of nicotine absorbed by the smoker, and a greater understanding of this balance would help to relate cigarette smoke composition to the addictive properties of cigarettes. This work presents data related to both air quality and tobacco smoke modeling.

The …

An Investigation Into Intermediate Grades Teachers' Noticing Of The Mathematical Quality Of Instruction, Krista Lynn Strand

Dissertations and Theses

The Mathematical Quality of Instruction (MQI) is an important feature of a classroom mathematics lesson. Before teachers can strengthen the MQI of their own lessons, however, teachers must first be able to notice MQI-related features of instruction. The purpose of this dissertation is to investigate intermediate grades teachers’ MQI-related noticing as they go through a ten-week research-based MQI professional development (PD) program. Specifically, this dissertation is guided by two research questions: (1) How do individual teachers’ noticing of MQI-related features of instruction shift as they go through an MQI-focused professional development program? and (2) How do teachers approach the task …

Faculty Senate Monthly Packet March 2016, Portland State University Faculty Senate

Faculty Senate Monthly Packets

The March 2016 Monthly packet includes the February agenda and appendices and the Faculty Senate minutes and attachments from the meeting held February 2016.

An Investigation Of School-Based Specific Learning Disability Identification, Bonnie Heather Bartos

Dissertations and Theses

Researchers have described the special education identification process for students with specific learning disabilities (SLD) as "muddled and confused" (Bocian, Beebe, MacMillan, & Gresham, 1999) and "haphazard" and "capricious" (Shinn, 2007, p. 603). Bocian, Beebe, MacMillan, and Gresham (1999) proposed the theory of competing paradigms as a way to explain why researchers and school-based eligibility teams identify different groups of students as SLD. This qualitative study had two research questions: a) To what extent did interviews of secondary resource teachers reveal the concepts of relativity, acceptability, and profitability as they reflect on the SLD process? and b) What other themes …

Pharmaceutical Contaminants As Stressors On Rocky Intertidal And Estuarine Organisms: A Case Study Of Fluoxetine, Joseph Richard Peters

Dissertations and Theses

Contaminants such as pharmaceuticals are of increasing concern due to their ubiquitous use and persistence in surface waters worldwide. Limited attention has been paid to the effects of pharmaceuticals on marine life, despite widespread detection of these contaminants in the marine environment. Of the existing studies, the majority assess the negative effects of pharmaceuticals over an exposure period of 30 days or less and focus on cellular and subcellular biomarkers. Longer studies are required to determine if chronic contaminant exposure poses risks to marine life at environmentally relevant concentrations. Also scarce in the literature is examination of whole organism effects …

Dynamic Stall Of An Experimental Wind Turbine Blade, Matthew Scott Melius, Raúl Bayoán Cal, Karen Mulleners

Mechanical and Materials Engineering Faculty Publications and Presentations

To understand the complex flow phenomena over wind turbine blades during stall development, a scaled three-dimensional non-rotating blade model is designed to be dynamically similar to a rotating full-scale NREL 5 MW wind turbine blade. A time-resolved particle imagevelocimetry(PIV) investigation of flowbehavior during the stall cycle examines the processes of stall development and flow reattachment. Proper orthogonal decomposition (POD) and vortex detection techniques are applied to the PIV fields to quantify relevant flow characteristics such as vortex size, separation angle, and separation point throughout a dynamic pitching cycle. The behavior of the POD coefficients provides time scales for the transitional …

Carbon Sequestration In Managed Temperate Coniferous Forests Under Climate Change, Caren C. Dymond, Sarah Beukema, Craig R. Nitschke, K. David Coates, Robert M. Scheller

Environmental Science and Management Faculty Publications and Presentations

Management of temperate forests has the potential to increase carbon sinks and mitigate climate change. However, those opportunities may be confounded by negative climate change impacts. We therefore need a better understanding of climate change alterations to temperate forest carbon dynamics before developing mitigation strategies. The purpose of this project was to investigate the interactions of species composition, fire, management, and climate change in the Copper–Pine Creek valley, a temperate coniferous forest with a wide range of growing conditions. To do so, we used the LANDIS-II modelling framework including the new Forest Carbon Succession extension to simulate forest ecosystems under …

Assessing The Impacts Of Federal Forest Planning On Wildfire Risk Mitigation In The Pacific Northwest, Usa, Alan A. Ager, Michelle A. Day, Karen C. Short, Cody R. Evers

Environmental Science and Management Faculty Publications and Presentations

We analyzed the impact of amenity and biodiversity protection as mandated in national forest plans on the implementation of hazardous fuel reduction treatments aimed at protecting the wildland urban interface (WUI) and restoring fire resilient forests. We used simulation modeling to delineate areas on national forests that can potentially transmit fires to adjacent WUI. We then intersected these areas with national forest planning maps to determine where mechanical treatments are allowed for restoration and fire protection, versus areas where they are prohibited. We found that a large proportion of the national forest lands (79%) can spawn fires that burn adjacent …

Ecosystem Services In Managing Residential Landscapes: Priorities, Value Dimensions, And Cross-Regional Patterns, Kelli L. Larson, Jennifer L. Morse, Peter M. Groffman, Neil D. Bettez, Tara Trammell

Environmental Science and Management Faculty Publications and Presentations

Although ecosystem services have been intensively examined in certain domains (e.g., forests and wetlands), little research has assessed ecosystem services for the most dominant landscape type in urban ecosystems—namely, residential yards. In this paper, we report findings of a cross-site survey of homeowners in six U.S. cities to 1) examine how residents subjectively value various ecosystem services, 2) explore distinctive dimensions of those values, and 3) test the urban homogenization hypothesis. This hypothesis posits that urbanization leads to similarities in the social-ecological dynamics across cities in diverse biomes. By extension, the thesis suggests that residents’ ecosystem service priorities for residential …

Climate Change Decreases Nitrogen Pools And Mineralization Rates In Northern Hardwood Forests, Jorge Durán, Jennifer L. Morse, Peter M. Groffman, John L. Campbell, Lynn M. Christenson, Charles T. Driscoll, Timothy J. Fahey, Melany C. Fisk, Gene E. Likens, Jerry M. Melillo, Myron J. Mitchell, Pamela H. Templer, Matthew A. Vadeboncoeur

Environmental Science and Management Faculty Publications and Presentations

Nitrogen (N) supply often limits the productivity of temperate forests and is regulated by a complex mix of biological and climatic drivers. In excess, N is linked to a variety of soil, water, and air pollution issues. Here, we use results from an elevation gradient study and historical data from the long-term Hubbard Brook Ecosystem Study (New Hampshire, USA) to examine relationships between changes in climate, especially during winter, and N supply to northern hardwood forest ecosystems. Low elevation plots with less snow, more soil freezing, and more freeze/thaw cycles supported lower rates of N mineralization than high elevation plots, …

Mapping Of Defects In Individual Silicon Nanocrystals Using Real- Space Spectroscopy, Dmitry A. Kislitsyn, Vancho Kocevski, Jon M. Mills, Sheng-Kuei Chiu, Christian F. Gervasi, Benjamen N. Taber, Ariel E. Rosenfield, Olle Eriksson, Ján Rusz, Andrea Mitchell Goforth, George V. Nazin

Chemistry Faculty Publications and Presentations

The photophysical properties of silicon semiconductor nanocrystals (SiNCs) are extremely sensitive to the presence of surface chemical defects, many of which are easily produced by oxidation under ambient conditions. The diversity of chemical structures of such defects and the lack of tools capable of probing individual defects continue to impede understanding of the roles of these defects in SiNC photophysics. We use scanning tunneling spectroscopy to study the impact of surface defects on the electronic structures of hydrogen-passivated SiNCs supported on the Au(111) surface. Spatial maps of the local electronic density of states (LDOS) produced by our measurements allowed us …

Mechanisms Of Methane Transport Through Populus Trichocarpa, Ellynne Marie Kutschera, M. A. K. Khalil, Andrew Rice, Todd Rosenstiel

Physics Faculty Publications and Presentations

Although the dynamics of methane (CH4) emission from croplands and wetlands have been fairly well investigated, the contribution of trees to global CH4 emission and the mechanisms of tree transport are relatively unknown. CH4 emissions from the common wetland tree species Populus trichocarpa (black cottonwood) native to the Pacific Northwest were measured under hydroponic conditions in order to separate plant transport mechanisms from the influence of soil processes. Roots were exposed to CH4 enriched water and canopy emissions of CH4 were measured. The average flux for 34 trials (at temperatures ranging from 17 to 25 °C) was 2.8 ± 2.2 …

Semiconductor Film Grown On A Circular Substrate: Predictive Modeling Of Lattice-Misfit Stresses, Ephraim Suhir, Johann Nicolics, G. Khatibi, M. Lederer

Mechanical and Materials Engineering Faculty Publications and Presentations

effective and physically meaningful analytical predictive model is developed for the evaluation the lattice-misfit stresses (LMS) in a semiconductor film grown on a circular substrate (wafer). The two-dimensional (plane-stress) theory-of-elasticity approximation (TEA) is employed in the analysis. The addressed stresses include the interfacial shearing stress, responsible for the occurrence and growth of dislocations, as well as for possible delaminations and the cohesive strength of a buffering material, if any. Normal radial and circumferential (tangential) stresses acting in the film cross-sections and responsible for its short- and long-term strength (fracture toughness) are also addressed. The analysis is geared to the GaN …

Satisfaction, Water And Fertilizer Use In The American Residential Macrosystem, Peter M. Groffman, J. Morgan Grove, Colin Polsky, Neil D. Bettez, Jennifer L. Morse, Jeannine Cavender-Bares, Sharon J. Hall, James B. Heffernan, Sarah E. Hobbie, Kelli L. Larson, Christopher Neill, Kristen C. Nelson, Laura A. Ogden, Jarlath O'Neil-Dunne, Diane E. Pataki, Rinku Roy Chowdhury, Dexter H. Locke

Environmental Science and Management Faculty Publications and Presentations

Residential yards across theUSlook remarkably similar despite marked variation in climate and soil, yet the drivers of this homogenization are unknown. Telephone surveys of fertilizer and irrigation use and satisfaction with the natural environment, and measurements of inherent water and nitrogen availability in sixUScities (Boston, Baltimore, Miami, Minneapolis-St. Paul, Phoenix, Los Angeles) showed that the percentage of people using irrigation at least once in a year was relatively invariant with little difference between the wettest (Miami,85%) and driest (Phoenix,89%) cities. The percentage of people using fertilizer at least once in a year also ranged narrowly (52%–71%), while soil nitrogen supply …

Travel Mode Choice Framework Incorporating Realistic Bike And Walk Routes, Joseph Broach

Dissertations and Theses

For a number of reasons--congestion, public health, greenhouse gas emissions, energy use, demographic shifts, and community livability to name a few--the importance of walking and bicycling as transportation options will only continue to increase. Currently, policy interest and infrastructure funding for nonmotorized modes far outstrip our ability to model bike and walk travel. To ensure scarce resources are used most effectively, accurate models sensitive to key policy variables are needed to support long-range planning and project evaluation, and to continue adding to our growing understanding of key factors driving walk and bike behavior. This research attempts to synthesize and advance …

Field Geology And Petrologic Investigation Of The Strawberry Volcanics, Northeast Oregon, Arron Richard Steiner

Dissertations and Theses

The Strawberry Volcanics of Northeast Oregon are a group of geochemically related lavas with a diverse chemical range (basalt to rhyolite) that erupted between 16.2 and 12.5 Ma and co-erupted with the large, (~200,000 km3) Middle Miocene tholeiitic lavas of the Columbia River Basalt Group (CRBG), which erupted near and geographically surround the Strawberry Volcanics. The rhyolitic lavas of the Strawberry Volcanics produced the oldest 40Ar/39Ar ages measured in this study with ages ranging from 16.2 Ma to 14.6 Ma, and have an estimated total erupted volume of 100 km3. The mafic and intermediate lavas of the Strawberry Volcanics include …

Star Academics: Do They Garner Increasing Returns?, James Jeffrey Kline

Dissertations and Theses

This study examines the criteria which help academics receive National Institute of Health funds (NIH). The study covers 3,092 NIH recipients and non-recipients in the same department or institute at twenty-four universities. The universities are drawn from those below the top twenty in terms of receipt of NIH funds. With regards to performance, non- recipients have lower performance than recipients. A key determinant of the receipt of NIH funds is individual performance, as measured by the number of articles published and average citations per article in the two years immediately prior to the grant application. Professors receive more NIH money …

Consistent Estimation Of Route Choice Models For Dynamic Transit Assignment, Jeff Hood

PSU Transportation Seminars

Dynamic transit assignment models have the potential to improve local transportation agencies’ capability to forecast the demand for public transit facilities under conditions of limited capacity or varying reliability. In order to be useful in practice, the simulated route choices of passengers in these models need to reflect the behavior of actual residents observed in local travel surveys. Most analysis methods of revealed route choice preferences developed to date have either (1) not been proven to provide consistent estimates or (2) required an untenable computation time for practical applications. Furthermore, no model of transit route choice has accounted for variability …

Determination Of The Goos-Hänchen Shift In Dielectric Waveguides Via Photo Emission Electron Microscopy In The Visible Spectrum, Theodore Stedmark, Robert Campbell Word, Rolf Kӧnenkamp

Physics Faculty Publications and Presentations

Photoemission Electron Microscopy (PEEM) is a versatile tool that relies on the photoelectric effect to produce high-resolution images. Pulse lasers allow for multi-photon PEEM where multiple photons are required excite a single electron. This non-linear process can directly image the near field region of electromagnetic fields in materials. We use this ability here to analyze wave propagation in a linear dielectric waveguide with wavelengths of 410nm and 780nm. The propagation constant of the waveguide can be extracted from the interference pattern created by the coupled and incident light and shows distinct polarization dependence. The electromagnetic field interaction at the boundaries …

One-Dimensional Nanostructure And Sensing Applications: Tin Dioxide Nanowires And Carbon Nanotubes, Hoang Anh Tran

Dissertations and Theses

The key challenge for a nanomaterial based sensor is how to synthesize in bulk quantity and fabricate an actual device with insightful understanding of operational mechanisms during performance. I report here effective, controllable methods that exploit the concepts of the "green approach" to synthesize two different one-dimensional nanostructures, including tin oxide nanowires and carbon nanotubes. The syntheses are followed by product characterization and sensing device fabrications as well as sensor performance understanding at the molecular level. Sensor-analyte response and recovery kinetics are also presented.

The first part of the thesis describes bulk-scale synthesis and characterization of tin oxide nanowires by …