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Surface Temperature Analysis Report: Kellogg Creek Restoration & Community Enhancement Project
Get PDFKellogg Creek is located in the Kellogg-Mt Scott watershed which flows through downtown Milwaukie, Oregon into the Willamette River. At the confluence of Kellogg Creek and the Willamette River is the Kellogg Dam. This dam impedes salmon, steelhead, and lamprey movement up Kellogg Creek, which is known historically as a salmon and steelhead rearing and migrating habitat. A plan to remove Kellogg Dam and restore 14 acres of Kellogg Creek is in progress by North Clackamas Watersheds Council (NCWC) and partners. Water temperature studies in Kellogg Creek have been conducted for the past several years, this report analyzed thermal surface water temperature images that were collected during a drone flight. The findings from the thermal images identified several cool water regions, ranging from 11-18°C, suitable for salmon and steelhead. The image analysis was accompanied by a literature synthesis which was used to provide recommendations on restoration design element to NCWC. These restoration recommendations suggest the implementation of stream reconstruction, application of deep pools, and increase tree canopy coverage of Kellogg Creek. These restoration recommendations are to incorporate the cool water regions identified by the thermal image analysis. The goal is that these recommendations lead to a successful restoration project and create a more climate resilient ecosystem
PVC Biodegradation Potential of Native Fungal Strains From Mt. Hood National and Tillamook State Forests
Get PDFPolyvinyl chloride (PVC) is a toxic, degradation-resistant environmental waste product. Recent research has revealed fungal enzymatic activity capable of biodegrading plastics. As PVC infiltrates local environments, it becomes imperative to determine the adaptability of local fungi to PVC substrates. In this experiment, 100 local native fungal strains sampled from the Tillamook State and Mt. Hood National forests and one commercial strain of common oyster mushroom were investigated for their ability to colonize and digest PVC by direct isolation on 0.1% and 0.2% PVC-enriched limited growth media. Substrates for positive cultures were imaged using Fourier transform infrared spectroscopy to analyze potential polymeric degradation. Out of 100 strains, only the commercial Pleurotus ostreatus actively colonized PVC-enriched limited growth media, and none of the strains exhibited clearance zones consistent with recent research. FTIR data between samples and control reveal no detectable shifts between characteristic peaks at 3300, 1633, and 1033 cm-1 consistent with agarose in the limited media. Fungal biodegradation of PVC, agar, or both, is unclear from these data. Further experimentation includes the development of more homogenous PVC suspensions in growth media, liquid culture without agar, and optimization of fungal culturing and co-culturing with regards to time, heat, nutrients, pH, and other critical growth factors
Investigating a Link Between DNA Repair and DNA Replication in \u3ci\u3eEscherichia coli\u3c/i\u3e Using a Bacterial Two-Hybrid System
Get PDFCells rely on nucleotide excision repair (NER) to remove bulky DNA lesions, such as those caused by UV light. In Escherichia coli, NER involves the UvrABC complex, and includes two main pathways, global genomic repair and transcription-coupled repair (TCR). While TCR, which preferentially removes lesions that block RNA polymerase on the transcribed strand of active genes, is well studied, less is known about whether a similar coupling between repair proteins and replisomes blocked by damaged DNA exists. Such a process has been suggested by a high throughput interactome study, using the replisome subunit HolC as bait and the damage recognition repair protein UvrA as prey, but this interaction has not been verified. Here, I use the Bacterial Adenylate Cyclase-Based Two-Hybrid system to look for a direct protein-protein interaction between UvrA and HolC. Genes encoding HolC, UvrA, and UvrB were cloned into plasmid vectors to create fusion proteins that were tagged with either the T18 or T25 subunits of adenylate cyclase at their carboxyl terminus. Interactions between T18 and T25-fused proteins were then screened by observing the color of colonies produced on indicator agar plates. Blue colonies produced by co-transformations indicate a positive protein-protein interaction while white colonies indicate no protein-protein interaction. I observed blue colonies in all hybrid protein pairings involving UvrA-T18 as bait, even when the partner protein used was the T25 subunit alone, suggesting a high level of background expression from the reporter gene that was independent of a true protein-protein interaction. I discuss some experimental modifications that can be made to address the non-specificity of this assay
Forest Fires Increase Mid-Winter Snowmelt in the Western Oregon Cascades
Get PDFAs the spatiotemporal overlap between burned forests, seasonal snow, extreme precipitation, and mid-winter warming continues to increase with climate change, it is critical we quantify the impacts of forest fires and rain-on-snow (ROS) on mid-winter snowmelt and snow-water resources. In the Pacific Northwest, the release of large volumes of meltwater to downstream receiving water from already vulnerable snowpacks can have catastrophic consequences. I show that forest fires doubled mid-winter snowmelt proportions as compared to unburned reference sites, using a novel network of snow monitoring and micrometeorological stations installed across an elevational and forest type gradient in a burned watershed in the western Oregon Cascades. I also observed an increase in snowpack vulnerability during ROS events in the burned forests, particularly at mid elevations, where ROS induced snowmelt accounted for 22.5% more of annual snowmelt. As a result, total springtime snowpack storage was reduced by half compared to the unburned sites, due to more snowpack loss during midwinter rain-on-snow events than at the unburned sites. Higher net snowpack energy, driven primarily by longwave radiation at the lower and middle elevations, indicates minimal buffering capacity of these warm snowpacks in high density burned forest to increasingly common ROS events. Balancing preparations for mid-winter flooding due to increased ROS vulnerability and refining the timing of water storage to offset accelerated snow disappearance represents a pressing challenge for water managers in a changing climate
Conceptualising Coercion in Child/forced Marriage through an Intersectional Lens: Narratives of Survivors and Practitioners in the US
Get PDFThis article examines the nature and forms of coercion in the forced marriage of minors in the US. We explore: (i) direct emotional or physical force exercised by parents which is commonly underpinned by dominant constructions of gender and sexuality, a well-rehearsed theme in existing scholarship; (ii) the hitherto unexamined role of intersecting socio-economic disadvantages in vitiating consent; and (iii) how state policies/practices create conducive contexts for child/forced marriage, which is elided in existing scholarship. In extending existing conceptualisations of coercion in child/forced marriage, we explicate the ‘total burden of coercion’ through a focus on the contexts within which consent is constructed at the intersection of social relations of power based on gender, age, race/ethnicity, poverty, sexuality and state policy/practice. Our analysis also illuminates the complex nature of survivors’ girlhood decision-making in the face of coercive constraints within which their agential capacities are formulated and exercised, and risk negotiated and managed
Near Real-Time Prediction of Ground PM2.5 Concentrations Across Oregon Using GEOS-CF and Machine Learning Models
No full textDespite significant efforts to reduce air pollution, many states in the United States, including Oregon, still facing PM2.5 particulate pollution. Providing near real-time ground-level pollution forecasts is essential due to the frequent wildfires in the area. Numerous studies have forecasted pollution levels spatially and temporally, but mostly they only provide results at measured locations, not allowing for predictions at other sites. This study proposes an approach using GEOS-CF combined with machine learning models to forecast ground PM2.5 concentration for the entire state of Oregon, not just at monitoring locations. Outputs from GEOS-CF, including PM2.5 concentrations at 985 hPa altitude and meteorological parameters, are integrated with ground-level PM2.5 observation data to create a big data set. This dataset is used for training and validating six machine learning models: Decision Tree, Random Forest, Gradient Boosting Machine (GBM), XGBoost, CatBoost, and LightGBM. The accuracy of these models is evaluated using the coefficient of determination (R2), Mean Absolute Error (MAE), and root mean square error (RMSE). Based on accuracy, an optimal model is formed and used to forecast ground-level pollution, which is particularly necessary in rural areas where ground observation data is lacking
Post-Fire Delayed Tree Mortality in Mesic Coniferous Forests Reduces Fire Refugia and Seed Sources
No full textContext Ecological functions provided by fire refugia are critical for supporting conifer forest resiliency under increased fire activity across the western United States. The spatial distribution and persistence of fire refugia over time are uncertain as fire-injured trees continue to die over subsequent years post-fire. Objectives We examined how post-fire delayed tree mortality affects the spatial distribution and attributes of fire refugia at patch and landscape scales following high-severity wildfires. Methods To explore changes in fire refugia patch size, isolation, and fragmentation over time, we used high-resolution satellite imagery (3 m pixel size) following high-severity fires in Oregon’s western Cascades to map annual changes in the extent of live tree cover up to 3 years post-fire. Results Delayed mortality decreased live forest cover across all fire perimeters by 8.5% between 1 month and 3 years post-fire. Though prevalent across all forest types, adult to mature and fire-sensitive conifer species were the most vulnerable to delayed mortality. The number of refugia patches decreased by ca. 20%, and most (ca. 77%) were small, non-core patches (\u3c 60 m from the patch edge). In response to delayed mortality, which increased the extent of high-severity burned areas by 9% (ca. 12,000 ha), the area with little to no seed sources based on refugia distance2-weighted density increased by 375% (7632 ha). Conclusions Delayed mortality altered the size and spatial configuration of fire refugia across landscapes. Considering species-specific fire adaptations may help improve post-fire management strategies and a framework of conifer forest resiliency under novel fire regimes
From Novice to Expert: Exploring the Relationship between Information Literacy Threshold Concepts and Epistemological Development
No full textThe Framework for Information Literacy for Higher Education articulates the ways of thinking, knowing, and doing that are valued in the academic community. Prior to the Framework, several scholars explored the potential relationship between information literacy and epistemological development, or the ways in which learners develop their understanding of and positionality to knowledge creation. However, the intersections of information literacy and epistemological development have been underexamined in the era of the Framework. In this article, I analyze the Framework through the lens of two epistemological development models, the Epistemological Reflection Model (Baxter-Magolda, 1992) and Reflective Judgement Model (King & Kitchener, 1994), to identify the stages at which learners might need to be in terms of epistemological development to begin the journey of crossing information literacy thresholds. While the Framework makes transparent expert ways of thinking and acting, it does not provide details about how to support learners’ development of these understandings
Work In Progress: Using Internships as Means for Indirect Assessment of ABET Criteria 3 “1-7” Student Outcomes
No full textThe Electrical & Computer Engineering (ECE) Department at Portland State University (PSU) has developed a Power Engineering Internship (PEI) program that provides engineering career development pathways within the electric utility industry. The PEI is supported by several U.S. Department of Energy grants that aim to develop quality career opportunities and develop a future electric utility workforce that represents the nation’s diverse populations. The PSU ECE Department intends to use surveys of internship participants as assessment tools for its ABET accreditation process, in particular, the ABET Criteria 3 Student Outcomes (SOs). SOs relate to the knowledge, skills, and behaviors that students acquire as they progress through an engineering program [1]. They describe what engineering students are expected to know and should be able to do by the time they graduate. Engineering education literature presents multiple methods for using internships as means for assessing SOs. Methods include using self-assessments that derive from internship experiences as well as mapping survey responses from employers and interns to SOs. Such methods gain value as they are assessed over multiple years. However, the majority of this literature discusses assessment tools that were developed for the ABET 2000 Criteria 3 “a through k” SOs. One of our motivations is to provide assessment tools that can be used to assess modern Criteria 3 SOs based on students’ internship experiences