Digital Commons Network^™

Online Or In-Person: What Mode Of Conversation Makes People Feel The Most Socially Connected?, Nathan P. Gheorghita, Cynthia D. Mohr, Maryann Samson, Sheila Mccabe, Julia Lynch

Student Research Symposium

Since the onset of the COVID-19 pandemic, people have been spending significantly more time online. Today, people spend an average of 6 hours and 58 minutes online every day, and much of this time is spent socializing via various platforms. Many studies have examined the benefits and risks of socializing online, but few studies have examined online conversations specifically. In this study I aim to uncover the differences in perceived social connection based on the medium of conversation. To do this, I will administer the Connectedness During Conversations Scale (CDCS) to a sample of Portland State University students (N=80). The …

Computationally Assisted Mechanistic Analysis Of The Protonolysis Of A Pt–Me Bond, Clement Dasilva

Student Research Symposium

Mechanistic study of the protonolysis of (cod)PtMe2 could give insight into the activation of C-H bonds by platinum because it is the microscopic reverse reaction. Two possible mechanisms for the protonolysis of dimethyl platinum complexes have been proposed, with experimental and computational data supporting the single step, SE2, over the multistep, SE(ox) mechanism. New experimental work from our group supports a multi-step mechanism with multiple acid molecules. In this work, the SE2 mechanism as well as a proposed SE(ox) mechanism were computationally modeled with a single equivalent of acid, TFAH, and two equivalents using density functional theory. The modeled pathways …

Reducing Switching Noise And Losses In Two-Stage Electric Power Converters, Abhijeet Prem

Student Research Symposium

Advancements in semiconductor devices are enabling the design of better electrical power converter systems. Wide Bandgap (WBG) switching devices from Silicon Carbide and Gallium Nitride can operate at high temperatures, voltages, and frequencies with faster turn-on/off periods, improving converter performance over silicon devices. However, WBG technology is still new, and the rapid switching transitions of these devices lead to issues such as voltage overshoots, ringing, and electromagnetic interference, which need to be addressed for widespread adoption. This work introduces a new control method for reshaping the switching voltages, which overcomes the disadvantages of fast transition time without increasing the system's …

Exploring Speech Experiences, Cpib Scores, And Aac Assessment Experiences Of Autistic Aac Users With Intermittent, Unreliable, Insufficient, And/Or Expensive Speech, Karina Rayl, Pang Lee Herr, Brandon Eddy, Amy Donaldson, Stephanie Fuller, Alyssa Zisk

Student Research Symposium

There is growing evidence from the perspectives of speaking autistic people that augmentative and alternative communication (AAC) supports their self-expression and communicative agency. Despite the evidence supporting the communication effectiveness of AAC, autistic adults have reported that professionals often prioritized speech as the ideal communicative method rather than offering AAC as a communication option. This study will investigate autistic adults’ AAC assessment experiences and explore whether a modified version of the Communication Participation Item Bank (CPIB) self-rating questionnaire could be an effective tool to document the internal states of intermittent, unreliable, insufficient, and/or expensive speech. Surveys will be distributed to …

Trends Of Groundwater Levels Over Time, Parvaneh Z. Karch-Agnew

Student Research Symposium

Groundwater is water absorbed by the soil and earth beneath the surface, saturating it, and the groundwater level is the level at which the saturation zone ends near the surface. Despite groundwater’s critical importance, only a few studies have compared groundwater level changes from in-situ measurements made in different aquifers on diverse continents. Here, I analyzed groundwater level time series to characterize how groundwater levels have changed over time in different places. I used Python and Jupyter Notebook along with the pandas and matplotlib modules to graph groundwater level changes over time. The data analyzed here derive from a Hydroshare …

Exploring Attrition And Linguistic Shifts: The Impact Of Covid-19 And Anti-Asian Discrimination On The East And Southeast Asian Diaspora, Sam Mutschler-Aldine, Amy Wan-Ling Lin, Natalie Robison, Milntra Raksachat, Carolyn Quam

Student Research Symposium

This study investigates language and identity among speakers of East Asian and Southeast Asian languages in the United States, within the context of the COVID-19 pandemic and the concurrent rise in anti-Asian hate. We adopt a mixed-methods approach guided by three research questions exploring: (1) changes in language use since pandemic onset, (2) changes in perspectives on language identity since pandemic onset, and (3) effects of geopolitical climate, specifically the rise in anti-Asian hate, on language use and perspectives on language identity. Qualitative methodologies allowed us to capture a diverse range of language experiences. Many (but not all) participants indicated …

Exploring Factors That Contribute To Stem Transfer Student Sense Of Belonging, Brittney R. Gallant, Cate Pocitari

Student Research Symposium

There is an ongoing disconnect between the number of students who enter college intending to earn a STEM degree and the number of students who persist to degree, this is particularly true for transfer students. Sense of belonging has been named as a STEM persistence factor, yet how that belonging develops for transfer students is largely unknown. Here we used a mixed-methods design to explore the experiences of STEM transfer students at PSU (n=38). Participants completed a survey prior to participating in an interview. The survey and interviews explored their science identity, sense of belonging, and involvement in STEM-related activities. …

Histone Changes As A Response To Lactic Acid Selection In Cells Of Austrofundulus Limnaeus, Lori Tran, Jason Podrabsky, Chelsea Hughes

Student Research Symposium

The killifish Austrofundulus limnaeus is an extremophile native to small temporary ponds of Venezuela. Normal embryonic development of A. limnaeus is segmented into up to three stages of metabolic depression (diapause), and both developing and diapausing embryos can survive long bouts of the complete absence of oxygen (anoxia) by using anaerobic metabolic pathways. While there has been much focus on how mutations in DNA drive evolution, environmental stress can cause heritable changes to histone post-translational modifications (hPTMs) in multiple species. However, this evolutionary role of hPTMs has never been studied in A. limnaeus. Additionally, the possible evolutionary role of extracellular …

Textural Investigation Into Rapid Welding Transitions In The Tuff Of Leslie Gulch Along Succor Creek At The Mahogany Mountain-Three Fingers Rhyolite Field, Southeastern Oregon, Alicia J. Martinez-Garling, Martin J. Streck

Student Research Symposium

The Mahogany Mountain-Three Fingers Rhyolite Field (MM-TFrf) in southeastern Oregon, associated with mid-Miocene rhyolite activity and Columbia River flood basalts, has been the subject of geological scrutiny. Previous studies proposed separate origins for the tuff of Leslie Gulch (LGT) and Spring Creek, but Benson and Mahood (2006) suggested a single ignimbrite event at 15.8 Ma, prompting a reassessment of MM-TFrf's history. This research focuses on LGT, investigating textural disparities between welded and non-welded tuff formations. Petrographic examinations delve into the transformation stages of pyroclastic tuff deposition, revealing the dynamic influences of volcanological and magmatic processes on welded and non-welded tuff …

Observing Orobanche Uniflora Parasitism Of Four Sedum Species In Relation To Soil Composition, Devin J. Forest-Hines, Sophie Wille, Noah Flick, Maxxie Barr

Student Research Symposium

Sedums are commonly selected for green roof applications due to their horizontal growth, heat and drought tolerance, water-storage capacity, and heat absorption. A potential threat to sedum health is the presence of parasitic Orobanche. Orobanche are a genus of parasitic plants that extract nutrients, water and carbohydrates from its host via root attachments. This study seeks to investigate Orobanche parasitism on the four most abundant sedum species on a Portland State University green roof in relation to soil composition. Four sedum species were propagated in clear plastic compact-disc (CD) cases containing either mineral substrate, Miracle Gro, or a seedling mix, …

Why People Pee In Public: Is A Lack Of Public Restrooms Keeping Portland Too Weird?, Cece Austin

Student Research Symposium

Various factors, including gender, housing status, socioeconomic status, and disability, impact access to public restrooms in Portland, Oregon. A pilot program involving the implementation of public restrooms has caused a significant reduction in public defecation in San Francisco. This research demonstrates the efficacy of this existing working model, which could be similarly implemented in Portland with some adjustments. Portland has the Portland Loos, which are single-stall, outdoor public restrooms. Still, many are not open 24 hours. An analysis of publicly available Google reviews indicates consistent poor cleanliness and Portland Loos being locked at times when they are advertised to be …

Feesability Of Laryngeal Endoscopy Simulation Labs In Student Training: A Scoping Review, Anna Thut

Student Research Symposium

Fiberoptic Endoscopic Evaluation of Swallowing (FEES) involves passing a flexible endoscope through the nose and down the throat to provide a detailed view of the throat, airway, and vocal folds. With the scope in place, people can eat and drink, allowing the clinician to evaluate for safe swallowing. Speech-Language Pathologists (SLP) use FEES for diagnostic evaluation and to gauge therapy progress and effectiveness. Simulation training on a low or high-fidelity model may provide a bridge for SLP graduate students to gain competency before being introduced to FEES in a clinical setting. This review aims to gather evidence on the use …

Wildland Urban Interface Growth And Development Potentials In Deschutes County, Samantha Hall

Student Research Symposium

Policy can and has been used as a tool to reduce the risk communities experience from natural hazards by limiting development in areas most vulnerable. How and where development occurs directly influences the amount of risk a community experiences from natural hazards like hurricanes, earthquakes, flash floods, and wildfire among others. Development patterns that contribute to increased wildfire risk mostly occur within the wildland urban interface, a land use type where development is at the fringes or intercept of wildland areas and is more flammable due to surrounding vegetation, slope, local climate, and other factors. For this research, Deschutes County …

Plasma Ion Source, Nathan K. Davis

Student Research Symposium

It is well known that a plasma can be created with both high input power and ultra low pressure. The challenge is in creating these same plasma characteristics with both lower power while maintaining a higher pressure. We have developed an ion beam by careful manipulation of magnetic and electric fields. Magnetic fields are used to accelerate ambient electrons to ionize the low pressure gas into a plasma. Electric fields are used to extract the ions into a focused beam. To achieve these initial ionizations, an artificial vacuum is created to reach low enough pressures to ionize the gas. A …

Method Validation Of Metals In Environmental Soil Samples, Sofia Deangelis, Nana Nguyen

Student Research Symposium

Vehicles are a major source of metal accumulation in terrestrial environments. Green infrastructure, such as bioswales, has been implemented as a way to mitigate this damage. However, there is a limited understanding of the processes that occur in these bioswales as few go back after implementation to identify areas in the bioswale with accumulation of pollutants. Inductively coupled mass spectrometry (ICP-MS) has the potential to be used in this type of study due to the machine’s high sensitivity and selectivity. However complications can arise while using the ICP-MS to characterize complex environmental samples. This study seeks to optimize microwave assisted …

Qibc Analysis On Killifish Cells Under Anoxic Conditions, Jaina Canlas

Student Research Symposium

Faithful DNA replication is vital for all living organisms. Environmental stressors can cause a multitude of mutations and DNA lesions during replication leading to cell death if not accurately repaired. The annual killifish, Austrofundulus limnaeus, has a heightened tolerance to many known genotoxic stressors, including anoxia. Embryos of the annual killifish can survive months of anoxia during the dry season when the ephemeral ponds they inhabit, completely dry. During these exposures, they have shown they are capable of repairing substantial amounts of damaged DNA. This resilience has led us to hypothesize that A. limnaeus have enhanced DNA repair capabilities. …

Talking About Weight: Weight Stigma And Information Seeking, Alexandra N. Henrici, Lillian H. Mantel

Student Research Symposium

Guided by the Risk Information Seeking and Processing (RISP) model, this study explores the relationship between fear of discussing weight-related topics, or weight-related communication apprehension and weight bias internalization and tests the inconsistent RISP relationship between risk perception and information insufficiency. It investigates differences in weight-related communication apprehension in those who previously sought weight-related information from interpersonal or mediated sources. Using a survey of 64 undergraduate communication students, the study found that high levels of weight bias internalization correlated with high levels of weight-related communication apprehension. The study did not find a significant difference in weight-related communication apprehension based on …

Going Down An Incline With Chatgpt, Corey R. Sissons

Student Research Symposium

In our Large Language Model (LLM) research, examining ChatGPT 4, we devised a physics problem involving an object descending an inclined plane. Through variations in terminology such as "rolling," "sliding," "solid sphere," "hollow sphere," "wooden ramp," "no-slip ramp," and more, we sought to evaluate LLM responses for different scenarios. Our analysis aimed to discern whether the LLM’s answers exhibited expertise in the field of physics. This experiment sheds light on LLM’s ability to give accurate and precise physics answers as well as variation in responses to nuanced changes in problem formulation. This provides valuable insights into its proficiency and potential …

Competing Supramolecular Forces: Boron Coordination Vs Π-Π Stacking, Sidhaesh A. Agarwal, Gonzalo Campillo-Alvarado, Nicholas Lutz, Jesus Daniel Loya, Eric W. Reinheimer

Student Research Symposium

This study explores the impact of fluorination levels in azopyridine Lewis bases on their ability to direct the formation of B←N coordination adducts or cocrystals with phenylboronic ester. We hypothesize that the degree of fluorination can be used as a tool to control the outcome of supramolecular bonding competition, thus influencing complex self-assembly.

A series of azopyridines with varying degrees of fluorination were synthesized and reacted with phenylboronic ester. Their structures were analyzed using Hartree-Fock calculations, Hirshfeld surface analyses, and single crystal X-ray diffraction to assess the impact of fluorination on supramolecular interactions.

The study reveals that azopyridines with up …

Development Of A Two-Photon Laser Scanning Microscope, Jess Hollenbaugh

Student Research Symposium

The objective of this project was to convert a Sarastro 2000 confocal laser scanning microscope into a system capable of imaging using two-photon excitation (TPE) fluorescence for the use of the PSU biology department. TPE microscopy operates on the ability of fluorophores to accept two photons each with half the energy of a desired transition in a single quantum event via a virtual energy state and then emit a higher energy photon upon relaxation. This is preferable to single-photon excitation (SPE) due to the lower energy photons causing less damage to delicate biological samples. The adaptation process included physically altering …

Respiratory-Swallowing Coordination In Motor Neuron Disease: A Scoping Review, Mariam Z. Mansoor

Student Research Symposium

Respiratory-swallowing coordination (RSC) is essential for providing efficient breathing and optimal swallowing function. Most commonly used methods of measuring RSC include nasal thermistry, and respiratory inductance plethysmography (RIP) to determine direction and durations of airflow. Outcome measures include swallow apnea duration (SAD) and respiratory phase pattern (RPP), i.e., direction of airflow pre- and post-SAD. The goal of the current project was to conduct a scoping literature review of RSC, focusing on the motor neuron disease (MND) population, including people with amyotrophic lateral sclerosis (ALS). A multi-engine literature search was conducted in 2023-24 via PubMed and Google Scholar. No limitations were …

Guide Rna Design And Delivery For Crispr/Cas9 Editing In Annual Killifish, Keria N. Moritsugu-Vandehey, Isabel Henkes, Yekaterina Chmykh, Amie Romney, Jason Podrabsky

Student Research Symposium

The CRISPR-Cas9 genome editing tool has shown to be successful in knocking out genes in model organisms such as zebrafish, turquoise killifish, and cichlid fish. CRISPR-Cas9 genome editing has been demonstrated in many species of fish, but this technology has not been verified in the annual killifish, Austrofundulus limnaeus. We hypothesize that targeted editing of the tyrosinase gene in embryos of A. limnaeus would lead to the development of fish without the ability to produce melanin, the black/brown pigment molecule. Early embryos (1-cell stage) were injected with a Cas9 cocktail containing a mix of guide RNA molecules that target …

Characterization Of Chopped Carbon Fiber Reinforced Composites Produced Using Fused Deposition Modeling, Jonathon Tran, Rachel Shubella

Student Research Symposium

Fused deposition modeling (FDM) is an additive manufacturing (AM) process which can create parts with complex geometries in their final shape without need for additional specialized tools or devices. The FDM process builds parts by adding material layer by layer only where it is needed, saving energy, costs, production time for complex parts, and minimizing waste. Fiber reinforcement can significantly enhance the mechanical properties of a polymer material and depends significantly on the fiber length distribution and fiber orientation distribution of the final part. In this research, we investigated the various infill patterns of FDM printed Markforged onyx which is …

Comparative Life Cycle Assessment Of Recycling Processes For Perovskite Solar Cells, Juan P. Herrera, Jules Freeman, Achyuth Ravilla, Ilke Celik

Student Research Symposium

Perovskite solar cells (PSCs) have emerged as a promising option for solar energy generation. However, it is essential to consider the environmental impact of these innovative photovoltaic (PV) technologies as the industry moves towards commercialization. Researchers are currently exploring ways to recycle PSCs to recover valuable materials and reduce their environmental impact at the end of their life. To ensure the sustainability of PSCs, this study evaluates and compares the environmental impacts of five recently developed recycling approaches. The Tool for Reduction and Assessment of Chemicals (TRACI) method was utilized to measure environmental impacts in categories such as acidification (kg …

Interpersonal Experiential Learning And Cancer Research Training Designed To Enhance The Motivation Of Participating Interns Utilizing Self-Determination Theory: A Longitudinal Study With Photovoice Methodology, Alex Vazquez-Cortes, Dierdre Mckay, Connie Tran, Bridget Bugla, Tiffany Bui, Kaisa Holt, Anthony Phan, Clare Hansen, Amy Lin, Amanda Braley, Lisa Marriott Phd

Student Research Symposium

Historically, the underrepresentation of individuals from disadvantaged backgrounds, disabled, and diverse racial/ethnic groups in STEM fields is prevalent. Equity in stem fields allows for different perspectives and knowledge backgrounds allows for the cognitive diversity needed to tackle complex research topics. The Knight Scholars Program (KSP) aims to support underrepresented and disadvantaged high school and undergraduate students pursuing a research career by teaching them the tools they need to succeed. Spanning over three summers, KSP utilized the Self-Determination Theory (SDT) of motivation to create an inclusive learning environment and to strengthen the high schoolers' motivation to pursue research careers focusing on …

Pulse Modulation In Braided Pneumatic Actuators Mimics Contractile Behavior Of Biological Muscles, Mohamad Elzein

Student Research Symposium

Advancements in robotics and bioengineering aim to emulate biological muscle systems through robotic actuators, blending mechanical strength with biological adaptability. A lesser-explored aspect is mimicking the pulse-like control characteristic of biological muscles, which contract in response to action potentials from motoneurons, with muscle contractile force relying heavily on the timing between these potentials. This study explores the effect of pulse lengths and the gaps between pulses on braided pneumatic actuators (BPAs), which mimic the nonlinearity and dynamic response of biological muscles. It hypothesizes that artificial muscles utilizing pulse-based control will exhibit a similar force dependency on the intervals between pulses …

Evaluation Of Sleep Outcomes After Traumatic Brain Injury In Children Using Questionnaires And Actigraphy, Connie Tran, Sydney Weese, Cydni Williams Md

Student Research Symposium

Traumatic brain injuries are the result of a sudden external blunt force to the brain and can result in long-term complications or death. In pediatrics, it is the leading cause of acute and chronic sleep wake disturbances, as well as cognitive deficits, which can lead to a reduction in the quality of life. These impairments can later result in lowered performance in work and school settings or decreased psychosocial function. Although there is sufficient evidence that traumatic brain injuries contribute to is that it is unknown whether or not sleep wake disturbances contribute to an increase in the mentioned cognitive …

Deriving Analytical Design Constraints For Absolute & Relative Encoding Schemes In Functional Subnetworks, Cody W. Scharzenberger-Braet, Alexander Hunt

Student Research Symposium

As neural networks have become prolific solutions to modern problems, there has been a congruent rise in the popularity of the numerical machine learning techniques used to design them. While they are highly generalizable, numerical methods tend to produce networks that act as inscrutable “black boxes,” making it difficult to interpret their behavior. One solution to the problem of network transparency is to use analytical techniques, but these methods are underdeveloped compared to their numerical alternatives. In order to enhance the viability of analytical techniques, this work extends previous efforts to quantify the impact that non-spiking neural encoding schemes have …

Second Language Impacts On First Language Processing, Natalie Robison, Sarah C. Creel, Sarah Elkington, Judith Kelholt, Amy Lin, Carolyn Quam

Student Research Symposium

This line of research investigates attrition (loss of fluency) of native Mandarin language (L1) proficiency with increasing proficiency in English. English uses pitch to denote intonation (e.g., “it’s there?” versus “it’s there!”), while Mandarin uses pitch to indicate word meanings; e.g., /he/ means “drink” with a high, level tone, or “river” with a rising tone. The present study delineates between two alternative explanations for the prior finding (Quam & Creel, 2017) that English proficiency correlates with attrition of Mandarin tones, but not vowels. This pattern could be explained by 1) language assimilability (L1-L2 Assimilability Hypothesis), or 2) by tone being …

Dragon Pseudoscorpions Shed Light On Ancient Climate History In The Pacific Northwest, Joshua W. Hootman

Student Research Symposium

Pseudoscorpions are an ancient and diverse group of understudied arachnids, and there is much to be learned about their relationships to each other. Pseudoscorpions are one of many leaf-litter dwelling and low dispersing invertebrates that inhabit the forests of the Pacific Northwest. Previous phylogeographic studies of Pacific Northwest taxa have shed light on some of the climatic and geologic events that have shaped the area's flora and fauna. One purpose of this study is to determine if there is similar genetic structuring within the pseudoscorpion populations present in the study area, or if there is even more structure likely influenced …