Tag: Poster 17

The Genetics of Cell Division in C. elegans

Presenters: Jessica Jang, Sophie Tomczyk and Hayley Standage

Mentor: Bruce Bowerman

AM Poster Presentation

Poster 17

Cell division plays a crucial role in the development of life. The Bowerman lab focuses on the cytoskeletal development and regulation in C. elegans embryos. We use genetic screening for lin-2 and temperature sensitivity to select a viable set of mutants suitable for phenotypic analyses. DIC video microscopy documents time-lapse videos of mitosis in these mutant embryos. Strains with consistent mutant phenotypes, referred to as high penetrance, are submitted for further study. Mutants are categorized into phenotypic classes including osmotic sensitivity, P1 delays, meiotic mutants, and specific cell division defects. Following categorization of mutants, we will perform tests for dominance and complementation to verify if the allele already exists in our database. Complementation tests are not necessary for mutant strains with multiple phenotypic defects. However, if complementation test are performed and show that the allele does not already exist, DNA from the strain is isolated and sequenced in order to identify a new gene in the C. elegans genome. Ultimately, we are looking for the genes necessary for cell division. The study of this species can help reveal valuable infor- mation about the genetics of cell division in other organisms, particularly in humans.

Re-evaluating Recasts as Negative Evidence

Presenter: Amanda Hammons

Mentor: Rose Maier, Dare Baldwin

Poster: 17

Major: Psychology & German 

Marcus (1993) argues that recasts (feedback on children’s speech errors provided via a corrected version of the utterance) are of little value for language acquisition: although parents recast children’s errors, they also recast well- formed utterances. Perhaps, however, parents provide pedagogical cues that distinguish recasts with corrective versus non-corrective intent. If so, children might be especially receptive to recasts accompanied by corrective intent, and update their linguistic constructions accordingly. To test this, 5- and 6-year-old children are introduced to two novel verbs in present tense forms. Both verbs take irregular past tense forms, modeled after real irregular verbs in English (e.g. ling/lang modeled after ring/rang), so children’s initial attempts to use the past tense are typically overgeneralizations (e.g. linged). The experimenter recasts these errors in two conditions: In the informative condition, pedagogical cues signaling corrective intent accompany recasts. In the uninformative condition, recasts are linguistically identical but lack pedagogical cues to corrective intent. If these cues help children disambiguate corrective versus non-corrective recasts, children in the informative condition should show greater preference for the correct (irregular) past tense form over the incorrect (overgeneralized) form. This work contributes to the growing body of research on children’s use of social cues to disambiguate linguistic input in the service of language acquisition.

Procedural Justice of Court Appointed Experts: Procedural Justice and Power Differentials

Presenter: Benjamin Davies

Mentors: Robert Mauro and Robert Rocklin, Psychology

Poster: 17

Major: Psychology 

Studying procedural justice has ramifications for legitimacy, and ultimately, legal system success. Jurists are concerned that any departure from the adversary system would call the legitimacy of the system into question. The use of court appointed experts is one such departure. We aim to examine the perceptions of procedural justice in court-appointed experts and the moderating effect of power on this relationship. Participants will be presented with 4 vignette scenarios describing a civil negligence trial in which the plaintiff always loses. The subjective power (Individual, Corporation or Government Agency) of the plaintiff, and whether the 3rd testifying expert is court appointed/adversarial will be varied and participants will report their perceptions of procedural justice in addition to individual difference measures. We have two predictions; (1) Across conditions, court-appointed experts will be perceived as less procedurally just than adversarial experts and (2) There will be an interaction between court- appointed expert and plaintiff status, such that if there is a high status plaintiff and a court appointed expert, perceptions of procedural justice will be lowest. While results have not been collected, we believe these findings will add a new dimension to current understanding of the justice of legal processes, and pave the way towards a more in depth study of court-appointed experts.

Changes in Lacustrine Sediment Lithology from ca. 45,000 to 22,000 Years Ago Reveal Glacial Environments Near Triangle Lake, OR

Presenter: Brynn Harrison

Co-Presenters: Daniel Gavin

Faculty Mentor: Daniel Gavin

Presentation Type: Poster 17

Primary Research Area: Science

Major: Geography

The Pacific Northwest has experienced many changes in climate during the most recent glacial period. In order to understand how these changes are documented in the climate record, changes in sediment characteristics were examined in a 60-meter sediment core from a location near Triangle Lake, Oregon. This study focused on using loss- on-ignition to measure organic content, carbon and nitrogen percentages, texture and color analysis, and carbon and nitrogen isotope analysis. Based on the changes in sediment characteristics, the record could be broken down into two sections. The first section of the core, spanning 48,500 to 37,200 cal. yr BP (calibrated years before present), mainly consisted of clays with few visible erosional events (noted by sand layers) spread throughout the section. These sediments were compared with pollen-derived climate descriptions (described by Laurie D. Grigg and Cathy Whitlock) and were found to be consistent with a wet climate that fluctuated between cool and warm temperatures. The second section of the core, spanning 36.9 to 23.4 cal. yr BP, had abundant sand layers. This is consistent with rapid erosion and higher sedimentation rates, and corresponds to a cold and wet climate. Overall, the sediment characteristics correspond well to the pollen-inferred vegetation and provide additional inferences on the erosion as well as terrestrial and aquatic productivity during the period preceding glaciation.

Use of Dichloro-diphenyl-trichloro-ethane and Alternative Methods to Fight Malaria in Sub- Saharan Africa

Presenter(s): Sarah Wheeler − Biology

Faculty Mentor(s): William Bradshaw, Melissa Graboyes

Poster 17

Research Area: Natural/Physical Science

Malaria is a disease that seems foreign to many; a distant memory. Despite the lack of awareness of the breadth of this disease, the World Health Organization reported 216 million cases of malaria across the world in 2016, 445,000 of which resulted in fatalities. While malaria was eradicated in the US in 1951, it’s present across the globe, with the epicenter of the endemic in Sub-Saharan Africa. Malaria is a vector-borne disease, meaning an organism transfers the disease to a host.
The vector for malaria is Anopheles gambiae, which infects the host with the parasite Plasmodium. Eradication has been successful through the use of dichloro-diphenyl-trichloro-ethane (DDT) by spraying the interior of homes in the past, but the organic pesticide has been banned in many countries. This research focuses on how eradication occurred in the past, what is used today to fight malaria in Sub-Saharan Africa and methods currently being developed in laboratories. Specifically, a meta-analysis was conducted of studies concerning the effects of DDT on the environment and human health, mechanisms of A. gambiae mutations that lead to DDT resistance, alternative methods of fighting malaria and their success rate, as well as cultural and financial barriers that prevent eradication. Comparison of these studies suggests that a rotation of pesticides, including DDT in IRS is effective when paired with pesticide-treated nets.

Proposal for Textile Recycling at the University of Oregon

Presenter(s): Courtney Kaltenbach

Co Presenter(s): Alli Eroh, Stella Augustine, Caitlyn Mccall, Racheal Maloney, Maggie Craven

Faculty Mentor(s): Sarah Stoeckl

Poster 17

Session: Environmental Leaders ARC

We are in an age of fast fashion in which clothing is produced unsustainably on a massive scale. College campuses are where many trends develop and are expressed.While there are many opportunities to buy and sell used clothes near campus and in the greater Eugene area, there is a lack of clothing recycling and repurposing in Eugene, especially among college students. Once clothes develop holes, become stained, or become unwearable in any way, we struggle to find a use for them. We are going to create a proposal to begin a textile recycling program through the Student Sustainability Center in which there will be a permanent bin that anyone can bring any sort of textile to. We are hosting a pilot event at a freshman dorm in which we will be collecting unwanted clothing and textiles, handing out an educational zine, screening a documentary about fast fashion “The True Cost”, and leading an upcycling craft with unwearable clothes. We will use this event to collect data on the type of things donated and gauge the interest of college students with textile based activities. The goal of this project is to get students passionate about recycling their materials, specifically their clothing. We hope that through our pilot event and project proposals we will convince students and organizations around campus to lengthen the lifespan of their clothes and think critically about purchasing new garments.

A Novel Application of Carbon Nanohoops in Ion-Sensitive Devices: A Potential Story

Presenter(s): Patrick Fajardo

Faculty Mentor(s): Ramesh Jasti

Poster 17

Session: Sciences

Of the many types of ion-sensitive devices, one who’s potential has not been fully realized are chemically modified field effect transistors (CHEMFETs). These devices utilize ion receptors to detect specific target ions, commonly used to detect the presence of pollutants. One possible receptor is cycloparaphenylene (CPP), also called carbon nanohoops. In this research we determined the interaction between CPP and a variety of ions using CHEMFET devices, by measuring a change in output voltage at different ion concentrations. We expected CPPs to interact strongly with cations, as these molecules have an electron rich pore which has been applied as a chemical host in other systems. A preliminary screening showed an interaction between CPP and lithium, ammonium, and sodium cations. In addition control experiments established a baseline, in order to accurately quantify the interaction taking place. Further ion screenings, as well as ionic strength control studies, are future experiments that will be carried out to further characterize the interaction taking place.