Research poster for Summer Undergraduate Research Symposium 2019. Research was conducted with CURE funding in the Perez lab studying cellular senescence in the PS19 mouse model.
Succinate dehydrogenase (Sdh) inhibitor fungicides, such as boscalid, are effective for the management of gray mold caused by the fungal pathogen Botrytis cinerea. Unfortunately, resistance to boscalid was common among isolates of the pathogen from small fruits grown in Oregon. Boscalid-resistance is commonly associated with mutations in Sdh, especially in...
Sablefish is a highly sought after seafood delicacy for which aquaculture of this species has recently been developed. By understanding the immunological functions in sablefish, our goal was to develop a mammalian fluorescent bioparticle assay that can viably analyze the efficiency of phagocytosis, an important function of the immune system....
Oregon is the number three producer of strawberries in the nation despite the fact that Oregon strawberry acreage dropped from 2,600 acres in 2005 to 2,000 acres in 2014 (Beeles, 2015; NASS, 2019, Losh, 2017). With over three billion pounds of berries grown nationally each year, strawberries are an important...
A great variety of topologically protected defects exist in ordinary and exotic states of matter. Some of them are promising candidates for technological applications such as magnetic memory or quantum computers. Others possess some properties of elementary particles that could lead to potential applications in quantum fields. Nematic liquid crystals...
In 1877 John Kerr described an experiment that demonstrated a quadratic change in refractive index in a plate glass placed in a strong external electric field. This results in a nonlinear relationship between the average electric polarization within the materials and the intensity of the applied electric field. This opened...
Gamma ray bursts are some of the brightest events in the entire observable universe. Since the late 1960’s, thousands of gamma ray bursts have been observed and they have been researched extensively. However, there are still many mysteries which remain unsolved. One such mystery is whether or not the viewing...
Phytochemicals from the genus, Fagonia, have been attracting increasing attention due to their potential beneficial effects on human health, particularly, anti-cancer properties. Certain Fagonia species contain various types of phytochemicals such as saponins, alkaloids, cardiac glycosides, flavonoids, terpenoids, and tannins. In this study, we investigated the phytochemical composition of a...
Exciton polaritons are quasiparticles composed of a quantum superposition of matter and light states that arises from the coupling of a standing wave photon and an exciton. This research has two primary objectives: to design and fabricate a Fabry-Perot microcavity system in which to produce exciton polaritons; and to show...
Biogas can be used to generate energy from a wide variety of sources. Wastewater treatment sludge is an effective source of waste to be used for generation of biogas to make energy which can be used to heat homes and run businesses. This would help decrease the use of fossil...
Currently multi-canonical, and grand canonical Monte Carlo simulations exist, but do not always give all of the necessary information of the system. When using a 1-D (only changing in one variable) broad histogram Monte Carlo method a user would need to run a range of simulations in order to get...
The ability to focus light through strongly scattering materials is opening up exciting new avenues in many fields, such as optics, computer vision, biology, and medicine, which utilize light delivery and imaging techniques. Efficient, high resolution wavefront shaping and optimization methods are crucial to enabling this new capability.
In this...
Plasmon induced transparency (PIT) describes a spectral response of coupled plasmonic resonators in that coupling between bright and dark modes leads to a destructive interference resulting in a narrow transparency window. This process has many applications in material characterization and advanced optical devices such as slow light devices or ultrafast...
The dynein molecule is a peculiar motor protein recognized for its unique stepping behavior. Sometimes it steps forwards. Other times it steps backwards. It has even been observed to occasionally shuffle by beginning a step with the same domain many times in row. These motions make dynein an interesting object...
The current American free-roaming horse (Equus caballus) population far exceeds the appropriate population limit set by the Bureau of Land Management (BLM) to preserve resources on public lands. Several techniques have been tested to assist in decreasing repopulation rates. The purpose of the present study was to analyze two contraceptive...
Endophytes, foliage inhabiting fungi, are an unexplored source of fungal biodiversity and a potential resource for the production of bioactive natural products. In this research, leaf tissues from the species Arbutus menziesii, Rhododendron macrophyllum and the genus, Ilex and Salix were collected for the isolation of endophytic fungi. Fungal extracts...
Terahertz (THz) spectroscopy is a great tool not only to study fundamental physical processes such as many-body Coulomb interaction but also to develop ultrafast electronic devices. More specifically, intense THz fields interacting with semiconductors have exhibited strong nonlinear effect involving extreme carrier dynamics. In this experiment, intense THz radiation was...
Postpartum uterine inflammation (endometritis) is not uncommon in beef cattle, resulting in infertility and culling. Prolonged calving may contribute to the increased incidence of endometritis in heifers. Commonly used methods to treat endometritis in beef cattle include intrauterine antibiotics and/or hormone injections, which can result in meat residues. Platelet rich...
TiO₂ typically crystallizes into three polymorphs: brookite, rutile, and anatase. The phase selection problem in TiO₂ is the lack of understanding what conditions cause amorphous TiO₂ to crystallize into one of its three polymorphs during an annealing process. It has been recently shown that phase selection in TiO₂ is highly...
Past studies have shown that students struggle with main concepts of potential energy, such as reading graphs, understanding that potential energy can be negative, and, most pertinent to this research project, connecting potential energy to force. I designed an activity to help introductory physics students address these struggles. The activity...
The relationship between the index of refraction and the porosity of a material is that the index decreases with respect to the porosity. This property can be used to change the index of refraction of films which allows control of the reflection of the material. This is important because being...
Multivariable functions permeate physics, mathematics, and other sciences. Understanding how quantities in multivariable relationships change together – or co-vary – is important for studying physical systems. In this project, we asked junior-level physics majors to describe the covariation of quantities in a multivariable context given a 2D graph. We identified...
Since the advent of graphene, research on 2D materials has exploded. Countless experiments have uncovered novel properties that emerge when different layered crystals are cleaved down to only a few atomic layers in thickness. The most popular of these non-graphene 2D materials is MoS2, a semiconductor which has been of...
Using a plastic bottle, we explore the capabilities of a reflective phase-only Spatial Light Modulator (SLM) in removing wavefront aberrations using a Zernike polynomial phase mask, with the modulators phase depth limited to 0.8π radians. Wavefront aberrations, which can be modeled with Zernike polynomials, distort image transmission through various optical...
Motivated by the Navier-Stokes equations, which are a set of unsolved equations related to fluid motion in R^3, we explored the incompressibility condition and the Neumann boundary problem. After exploring, we noticed that using iterated Riesz transforms of the boundary data could be used to get information about the velocity...
Energy production and consumption is a major environmental and economic concern in the world today. Biofuel produced from lignocellulosic biomass is being explored as an alternative energy source to petroleum. Lignocellulosic biomass is comprised of cellulose, hemicellulose, and lignin. To produce biofuels, lignocellulosic biomass must be broken down to expose...
Due to public and regulatory restrictions, genetic containment technology is critical for research and development of transgenic trees in forestry. A multi-year field trial demonstrated that the RNAi-LFY construct successfully induces sexual sterility in 6K10 poplar (Populus alba) without visible effects on vegetative development. However, its limited number of replicates...
With over three billion pounds of berries grown nationally each year, strawberries are an important economic contributor to agriculture in the US (Grubinger, 2012). However the strawberry industry in Oregon has been in a period of transition over the past few years. Strawberry acreage, planted and harvested, as well as...
Autonomous buoys were deployed in 2011 in the central Arctic: An Ice-Tethered Profiler (ITP) and Ice Mass Balance (IMB) buoys were deployed in the Makarov basin; a Polar Ocean Profiling System (POPS) and Ice Thickness (Ice-T) buoy were deployed on the Eurasian Basin. The two different sites were approximately 70km...
Does the wage gap exist in careers that require higher levels of educational attainment? Research indicates that, on average, women make around 80% of what men earn. This study aims to investigate the relationship between educational attainment and the magnitude of the wage gap. Due to the differences in gender...
Do freshmen achieve less of their personal and academic short-term goals in comparison to upperclassmen?
Some may intuitively assume that due to age, or lack of experience, college freshmen would have lower perceived task-specific ability (self-efficacy) and actually achieve less (goal-completion ranging from 0% to 100%). Differences between various class-standing...
The largest source of uncertainty among climate models simulating the climate system response to increased atmospheric carbon dioxide concentrations is the cloud feedback, the amplification or dampening of the warming from the carbon dioxide forcing by clouds. Refining our knowledge of the cloud feedback is therefore essential to gaining a...
Any interaction with another person requires some judgement of their characteristics from a short amount of time. Each day a person can interact with many individuals and quick judgments have to be made in each situation to decide how to act or react. This means a person can make hundreds...
In the field of religious studies, it is common to separate meta theories about the concept of religion itself into two equally problematic categories that both make claims about the truth of religious doctrine. This is done by attempting to define religion by historically excluding non-Christian religious traditions from the...
Oral argument has always been an integral part of any appellate courts’ function. For most of the court’s history, both the advocates arguing before the Court and the judges presiding over the court were extremely similar; all being white males. However, the late 20th and 21st centuries have diversified both...
This study used a factorial mesocosm design to quantify American bullfrog (Lithobates castebeianus) eDNA to assess the relationship between body size, density, and eDNA shedding rates.
This paper is an assignment for my Ichthyology class at Oregon State University. I was tasked with creating a new fish species that is scientifically possible and telling a fictional story of its discovery.
Biohydrogen production via dark fermentation (DF) and microbial electrolysis cells (MEC) demonstrate great potential for sustainable hydrogen generation. In this study, DF and MEC were coupled as a hybrid reactor and evaluated using brewery wastewater. The effect of hydraulic retention time (HRT) and buffer concentration on reactor performance were assessed...
The thermal cross sections and resonance integrals for neutron capture by ⁷⁴,⁷⁸,⁸⁰,⁸²Se were measured using the same procedure and equipment for all of the isotopes. Uncertainty and absence of accurate previous values for several isotopes introduces a need of measuring these parameters using similar techniques. This was done using OSU’s...
Polycyclic aromatic hydrocarbons (PAHs) are a class of contaminants ubiquitous in the environment and result from the incomplete combustion of fossil fuels. Many PAHs have been identified as procarcinogenic, and are metabolized to form DNA adducts; however, other mechanisms also may contribute to toxicity and help explain differences in toxicity...
Bacterial endophytes have the potential to confer benefits to Douglas-fir ( Pseudotsuga menziesii ), for instance drought tolerance. Bacterial endophytes originating from seeds are especially important. This is because seed endophytes are more likely to be the first endophytes to get established within the young host plant. The goals of...
In order to reduce the cost of lignocellulosic ethanol production, a model was previously developed to predict the amount of fermentable sugar released based on parameters concerning both biomass and enzymes. To validate this model, enzymatic hydrolysis must be carried out using individual purified cellulase enzymes. Endo-1,4-β-D-glucanase I (EG I),...
1. To determine whether plastics are being ingested by black rockfish at three sites along the Oregon coast
2. To determine if there is a significant difference in rates of plastic ingestion between marine reserve locations and Newport location.
3. To quantify the extent of plastic ingestion and to identify...
In current nanotoxicology research, there is a lack of standardization in reporting of zebrafish exposure media and sonication practices. This lack of standardization in use and reporting methods has made reproducing nanoparticle (NP) toxicity results between labs a common issue. It is important to have a standardized way of reporting...
There exists a growing need to establish a better in vitro model for evaluating PAH toxicity and carcinogenicity and to improve assessments of risk to human health, especially to the complex mixtures that exist in the environment. Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants due to the incomplete combustion...
In current nanotoxicology research, there is a lack of standardization in reporting of zebrafish exposure media and sonication practices. This lack of standardization in use and reporting methods has made reproducing nanoparticle (NP) toxicity results between labs a common issue. It is important to have a standardized way of reporting...
There exists a growing need to establish a better in vitro model for evaluating PAH toxicity and carcinogenicity and to improve assessments of risk to human health, especially to the complex mixtures that exist in the environment. Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants due to the incomplete combustion...
Organic photovoltaics are being explored as the next generation material for semiconducting and optoelectronic devices but are limited by their stability and efficiency. One new candidate is crystallized Anthradithiophene (ADT), which is a promising photo-voltaic material due to its high quantum yield and adjustable side groups. The side derivatives TES-F,...
The equation of state for a fluid described by the Weeks-Chandler-Andersen (WCA) potential was solved to determine at what pressures and temperatures the fluid will theoretically freeze. A Monte Carlo (MC) algorithm was used to sample a system of 256 spheres for a set of thermodynamic averages to locate and...
Computational simulations of disks are becoming an important tool to predict the the evolution of protostars and disks to better understand the formation of planets. Past research has shown that the evolution of disks and their protostar can be altered through the interaction between gravity and hydrodynamic instabilities. We perform...
Xylindein is an organic pigment derived from Chlorociboria aeruginascens and C. aeruginosa fungi that has shown promise as an organic semiconductor. Preliminary estimates of charge carrier mobilities (CCMs) on the order of 0.1 cm2/Vs were calculated from early tests on xylindein thin films, and photocurrents were also observed under laser...
The response of cells to periodic driving is important for many biological processes, particularly blood flow and heart functioning. Our research analyzes the collective shear stress response of fibroblast cells due to a periodic driving frequency. When cells experience shear stress, they release calcium into the cytosol. To quantify the...
Bacteria are critical to the health of eukaryotes and the ecosystems in which they persist. Some symbiotic interactions are mutualistic in which both microbe and host benefit from the partnership. Other interactions are parasitic, and the microbe typically benefits at a cost to the host. Rhodococcus is a genus of...
As engineered nanomaterials (ENM) become more common in consumer products, it is crucial to rapidly assess toxicity of unique ENM. Previous studies rarely focused on standardizing nanotoxicity testing, leading to inconsistent and irreproducible results. This study characterized a variety of ENM of different size, shape, core type, and surface charge...
The prevalence of obesity and diabetes in the United States and globally has been rising in the last few decades and it continues to climb. One of the causes for this increase is the over consumption of sugars and/or carbohydrates. Among medications available to treat obesity and diabetes are the...
Cascadia’s 1700 earthquake generated a tsunami and widespread subsidence along Pacific Northwest coastline. The tsunami deposited sandy sediments in many Oregon coastal estuaries, such as Alsea Bay. Although the recurrence of subduction-generated megathrust earthquakes and tsunami events in this region are recorded in the stratigraphy, knowledge of the full inland...
Fluorescent proteins have emerged as an essential toolset for bioimaging, creating a demand for engineering proteins with new and improved fluorescent properties. In this thesis, I explore the atomistic structure of REX-GECO1, a newly engineered protein biosensor that has unique optical properties. Since this protein has no available crystal structure,...
Freshwater resources are becoming more and more scarce worldwide, and rights to water use is becoming more competitive between stakeholders. Irrigation for agricultural purposes accounts for a large portion of freshwater usage. Using drought tolerant plant species in irrigated pastures could become a necessity in order to reduce competition for...
A focus group format was used to investigate and identify favorable and unfavorable communications between two strangers, an AAC (Augmentative/Alternative Communication) device user and their communication partner. The principal interest was in the feedback gained from an ALS (Lou Gehrig’s disease) support group at the Salem Hospital which included participants...
Coral reefs have become extremely vulnerable to rising ocean temperatures, with mass bleaching events increasing in frequency and severity. If bleaching events persist annually, models predict that more than 90% of reef species will face long-term degradation. However, recent evidence has shown that corals may be able to thermally acclimate...
Beneficial insects could provide valuable pest control services on Oregon Christmas tree farms, but a limited amount of data exist that quantifies the type and abundance of beneficial insects on farms. This study surveyed beneficial insects on two farms that differed in their management strategies as well as other abiotic...
Beneficial insects could provide valuable pest control services on Oregon Christmas tree farms, but a limited amount of data exist that quantifies the type and abundance of beneficial insects on farms. This study surveyed beneficial insects on two farms that differed in their management strategies as well as other abiotic...
The details of the 1700 Cascadia Subdction Zone earthquake and tsunami can be better constrained using data from tsunami sand sheets, provided knowledge of the waveform, estuary geometry and bed roughness controls on the deposition pattern of the sand sheet. In this study, we use the hydrodynamic and sediment transport...
A flipped classroom provides students with course content in the form of videos, readings, and/or simulations that they complete during the time traditionally used for homework assignments while in-class time is devoted to hands-on group learning activities. Project BoxSand is gathering quantitative data on how students in a flipped classroom,...
The optical transition in high-fraction polymorphs of titania (TiO2) were investigated to determine the band gap behavior of the most common polymorphs—brookite, rutile, and anatase—the values of which are varied in the literature. The direct optical band gaps of brookite, rutile, and anatase, were determined to be 3.37(7)eV, 3.41(11)eV and...
Weight bias has dramatically increased over the last 20 years
and is as prevalent as bias based on race and gender. The
media is a primary source of weight bias according to a review
of weight-related content within newspapers, popular press
books, television, and movies. Bias is perpetuated through
messages...
This research analyzes the effects of unauthorized immigration on unemployment levels in the states of Texas and California in the United States. Data from the Department of Homeland Security is utilized to best estimate the size of unauthorized populations. This research finds that a one person increase in the unauthorized...
This article analyzes how this transition occurred and what significant developments took place that allowed beer and ale to become a tradable and profitable good on the European market. Specifically, it examines the development of brewing as a tripartite progression: (a) that beer and ale were brewed in the 3...
Carbonic anhydrases are ubiquitous enzymes that catalyze the reverse hydration and dehydration of carbon dioxide and bicarbonate respectively. A variety of tumors in humans show overexpression of human carbonic anhydrase II (HCA II) leading to an acidic breakdown of carbon dioxide into bicarbonate. While a variety of drug inhibitors exist,...
The calculation of interplanetary trajectories is a numeric problem which requires a high degree
of precision for the results to be accurate. A computer program was written for this project which
uses leapfrog integration combined with Newton’s method of iterative root finding to find ideal
interplanetary trajectories. Reasonable initial conditions...
Nanostars have many potential applications, particularly in biomedicine, such as drug delivery, detection assays, and even cancer treatment. Seeing how their plasmon changes in response to changes to the environment of the nanostars can give us an insight to the stability of the nanostars. Our current studies involve the effect...
In order to reduce the cost of lignocellulosic ethanol production, a model was previously developed to predict the amount of fermentable sugar released based on parameters concerning both biomass and enzymes. To validate this model, enzymatic hydrolysis must be carried out using individual purified cellulase enzymes. Endo-1,4-β-D-glucanase I (EG I),...
Ocean acidification has led to many issues regarding the decline of calcifying organisms, such as
coralline algae. Acidified sea water inhibits precipitation of CaCO3 that affects the structure and
growth of coralline algae. Therefore, non-calcifying algae may outcompete calcifying algae in the
intertidal systems with future acidic ocean condition. Variety...
Symbioses are intimate interactions between two different organisms. In a pathogenic interaction, one organism benefits and the other is generally harmed; whereas in a mutualistic interaction, the members reciprocally benefit. Rhodococcus is a genus of Gram-positive bacteria that persist in a variety of terrestrial and aquatic ecosystems. Although better known...
Previous behavioral studies have suggested that the automaticity of face recognition depends on familiarity. We sought converging evidence for this claim using electrophysiological measures. In Experiment 1, participants first rated their familiarity with 6 male celebrities. They then performed dual tasks in which Task 1 required a tone/noise discrimination. For...
Dynein is a motor protein which transports cargo along tracks inside the cell. Like related motor proteins kinesin and myosin, dynein uses cellular energy to take steps with its two foot domains. Unlike kinesin or myosin, dynein’s stepping pattern is highly varied: it can take steps between zero and 60nm...
An analysis on the work of Tim O'Brien's "The Things They Carried" and his ability to create powerful imagery and contextualize the unknown of war for the those who have never taken part.
--Vietnam Experience Final Paper
The physical properties of hydrochloric acid and deuterium chloride were derived through the use of the harmonic oscillator and rigid rotor quantum mechanical models. By first obtaining angular momentum quantum values for HCl and DCl through Fourier Transform Infrared Spectroscopy, these two systems could be summed and processed with additional...
Dynein is a motor protein which transports cargo along tracks inside the cell. Like related motor proteins kinesin and myosin, dynein uses cellular energy to take steps with its two foot domains. Unlike kinesin or myosin, dynein’s stepping pattern is highly varied: it can take steps between zero and 60nm...
Research of an outreach to industry alumni to identify weak points in our graduates competencies and attempting to close those gaps through various recommending various resources for the administration to offer.
Semiconducting materials are of immense importance due to their presence in almost all modern devices. It is possible that the surface physics of semiconductors could be used to control the nanoscale topography and properties of these materials, ultimately creating new options for device fabrication. This could result in profound implications...
We computationally modeled protostellar star-disk systems with star to disk mass ratio of 10. Our computational models looked at the development of density perturbations in these systems for different geometries of the system. The ratio of the star’s height and radius (rₚ/rₑ) is varied between 0.1746 and 0.88095. We modeled...
Microbial electrolysis cells (MECs) for hydrogen production exhibit great advantages over many other biohydrogen production techniques in terms of versatility of substrate and hydrogen yield. However, hydrogen scavenging by methanogens put forward a great challenge to the application of the single chamber MECs when using mixed culture. Various strategies were...
The Mount Thompson 7.5 Minute Quadrangle is located in the central Boulder Batholith, between the cities of Butte and Helena. The Boulder batholith is host to numerous metalliferous vein deposits, including those in the Butte District. Recent USGS (EDMAP)-funded geologic mapping at 1:24,000 scale in the Mount Thompson Quadrangle during...
Understanding the electrical transport properties of graphene provides a basis for determining its future as a potential semiconducting device that can be used for the next generation of transistors and photodetectors. Graphene p-n junctions can also function as field effect transistors, and thus are a logical starting point for I-V...
Carbon dioxide emissions greatly affect the carbon chemistry mechanisms within the ocean. Carbon absorbed by the ocean, drops the pH level and creates an environment that is acidic. Acidic conditions prevent calcification mechanisms in coralline algae, and hinder their ability to establish within the intertidal. Coralline algae display structural relevance...
Modifications of histone tail amino acid residues are necessary for many reactions involving chromatin. These processes can produce transcriptionally active, euchromatic, or inactive, heterochromatic, segments of DNA. The formation and maintenance of facultative heterochromatin is critical for the proper growth and development of many eukaryotes. Euchromatin can be changed into...
Yaquina Bay, Oregon, has been introduced to a few The invasive species in Yaquina Bay, Oregon can have a huge effect on the native species and local ecosystem. European green crab (Carcius maenas) is an invasive species. The European green crab can be found on the mudflats competing with the...
Kinesins are intracellular motor proteins that transform chemical energy into mechanical energy through ATP hydrolysis to move along microtubules. Kinesin roles can vary among transportation, regulation, and spindle alignment within most cells. Many kinesin have been found to move towards the plus end of microtubules
at a steady velocity. For...
We measure the charging and discharging of two organic materials, PCBM and ADT-TES-F. These materials are studied through the noncontact method of particle trapping known as Optical Tweezers, where an IR laser is used to constrain the motion of a coated or noncoated silica sphere while its positional data is...
Increased coastal development poses a potential threat to nearshore habitats in Alaska, and artificial reefs (AR) are an increasingly popular tool for mitigating habitat loss. Although well studied in tropical and temperate locations, less is known about AR efficacy in high latitude locations. Since ARs are heavily influenced by ecological...
Ocean acidification is negatively impacting organisms that use calcium carbonate to form their shells. Increasing OA conditions are putting a strain on these calcareous animals by weakening their shells, thus causing them to become more vulnerable to predation. Worsening shell integrity may lead to a decline in hard-shelled prey populations...
Understanding charge transfer in organic semiconductors is important for developing devices like organic light emitting diodes and flexible electronics. Optical tweezers have been used in many disciplines for trapping, manipulating, and analyzing microscopic objects such as microspheres, micro-organisms, and other colloidal particles. Using optical tweezers, studies have measured the average...