Category: 2012

Pulse Laser Physics: Constructing a Stretched Pulse Fiber Laser and Autocorrelator

Presenter: Alexander Muhr

Mentor: Stephen Gregory

PM Poster Presentation

Poster 32

Creation of laser pulses in the sub picosecond range has become increasingly important over the past couple of decades as the number of applications for ultrashort laser pulses has expanded. There are a number of ways to create sub picoseconds laser pulses; one such method is to use a stretched pulse fiber laser. This method is advantageous because stretched pulse fiber lasers are relatively inexpensive to build, compact, and operate efficiently. For practical purposes, it is also important to be able to characterize and measure sub picosecond pulses, especially their temporal duration. Due to the incredibly short duration of such pulses standard detection methods will not work. A solution to this problem is to use techniques which marginalize the slow response of the detector, one such technique being autocorrelation. This study has identified a number of important features essential to producing both a stretched pulse fiber laser and autocorrelator. At this point in time, we have created a stable stretched pulse fiber laser but have not been able to produce an autocorrelation of the laser pulses. Consequently, we do not exactly know the temporal duration of the laser pulses produced by the stretched pulse fiber laser.

The Effect of Muscle Strength on Performance during the Sit-to-Walk Task in Elderly Subjects

Presenter: Hannah Miller

Mentor: Li Shan Chou

PM Poster Presentation

Poster 30

Aging results in declines in many physiological functions, which can negatively affect the performance of everyday activities such as mov- ing from a sitting position to walking. This study was intended to determine how decreases in lower extremity strength can negatively influence elderly performance during Sit-to-Walk, putting them at risk for falling. Forty eight subjects above the age of 70 were recruited to perform the Timed-Up-and-Go (TUG) as well as strength tests targeting hip abductors, knee extensors and ankle dorsiflexors. Lower strength subjects took longer to complete the TUG test. Smaller GRFs were correlated with longer duration of TUG, which indicates a decrease in overall performance and a higher probability of falling as a result of poor muscle strength. This study provides an explanation to how muscle strength correlates with performance in terms of GRF’s and time.

Interactive Children’s Pet Care System

Presenter: Natasha Michalowsky

Mentor: Jason Germany

PM Poster Presentation

Poster 28

The vov.vov system leverages technology and social media to enhance, elevate and expand dog ownership for children. Children are not great dog owners because they lack knowledge about how to train and care for a dog and require assistance from parents to remember to care for their pet. This product empowers children to learn how to be great dog owners through an informational social network and interactive watch. The slap watch is inherently adjustable to any size wrist. There are no sharp edges to cut oneself on or loose parts that could cause a choking risk. Although it is designed with a focus on children ages 7-10, the system will work for a far wider array of ages. The interface is simple and has both images and words to allow children without developed reading skills to use the system. The touch screen interface is intuitive to any age and simple to use. The social network allows the watch to teach more complex skills over time as the data about the child’s age is factored into the tasks and information in the watch. Consumers are comfortable with the interaction of the analog and digital worlds, which makes the timing ideal for creating a product to help children with their analog tasks using the technology and interaction they enjoy. Technology has successfully made positive changes in adult lifestyles with products like the Nike+ watch and this is the opportunity to expand the market to children.

Archaeology from Behind the Curtain: The Discovery, Research, and Conservation of Human Remains in Gozo, Malta

Presenter: Kirsten Lopez

Mentor: Diane Baxter

PM Poster Presentation

Poster 26

“Box 1” and “Box 2”–that was it. That is all that was written on the outside of the boxes that ultimately contained the contents of my research project. In the fall of 2011 I undertook an opportunity to experience museum collections and curation in Gozo, Malta, during an internship offered by IE3 through the University of Oregon. While I had experience working with collections here on campus, the ability to learn cross-cultural differences in storage, display, and perceptions of the past could not be passed up. As I went through my internship assisting with cataloguing of the contents of a storage facility, I stumbled upon these two boxes. With the encouragement of Heritage Malta and the Museum of Archaeology, Gozo, I developed a small project that addressed three questions: where did the re- mains come from, who were they, and how can we best preserve them for future research? Through an interview with a prior museum administrator, sorting, documenting, and obtaining professional verification on the dating of a diagnostic pot, I was able to discertain the location of recovery during 1980/1986, the remains as Tarxien Temple Period (3000 – 2500 BC), the minimum number of individuals (MNI), notable signs of pathology, and a complete rehousing and storage culminating in a written preliminary report. After considering nearby sites and the landscape involved, these remains may also prove to be key in a turning point for prehistoric Maltese archaeology as one of two skeletal collections of the Temple Period.

Interactions Between ihha and mef2ca in Bone Development

Presenters: Ashlin Larsen, Tyler R. Huycke and Charles B. Kimmel

Mentor: Charles Kimmel

PM Poster Presentation

Poster 24

Bones form through the differentiation of mesenchymal cells into bone-forming osteoblasts, and multiple genes regulate this process in order to ensure proper bone size and shape. Myocyte enhancer factor 2ca (mef2ca) encodes a transcription factor that negatively regulates development of the opercle (Op), a craniofacial bone of the zebrafish. Loss of mef2ca can lead to ectopic bone growth along the antero-ventral edge of the Op, yet the developmental mechanism underlying this process is unclear. We tested whether indian hedgehog a (ihha), a positive regulator of Op development acting in the same region of bone that mef2ca negatively regulates, is required for the complete ectopic bone growth seen in mef2ca mutants. With fluorescent in situ hybridization we show that expression of ihha and ptch1, a downstream target of active Hedgehog signaling, is present in ectopic bone growth of mef2ca mutants, suggesting that mef2ca may regulate Ihha signaling to pattern bone. Furthermore, analysis of mef2ca; ihha double mutant larvae reveals many ventrally reduced bones that resemble ihha single mutants; however, many also display the mef2ca mutant phenotype. Therefore, although Ihha is required for certain mef2ca mutant phenotypes, it is not imperative to induce expansion of bone in mef2ca mutants, and thus mef2ca must im- pose its negative regulation of bone development by acting through distinct gene networks in addition to the Hedgehog pathway.

Characteristics of Menstrual Cycle Manipulation with Combined Hormonal Contraception in a University Student Population

Presenter: Hannah Lakehomer

Mentor: Chris Minson

PM Poster Presentation

Poster 22

The purpose of this study was to assess the frequency and characteristics of menstrual cycle manipulation with combined hormonal contraception (CHC) among a population of college-age women. A self-administered email survey on menstrual cycle practices and beliefs was distributed to all female students at the U of O. Assessment of participant characteristics, menstrual cycle manipulation features, and attitudes/knowledge toward CHC was analyzed using standard statistical methods and probit models. Of respondents, 79.9% reported using CHC currently or recently and 20% of these women reported altering their menstrual cycle pattern or using ex- tended cycle regimens to delay/skip their menstrual periods. Of cycle manipulators, 47% indicated that they learned this practice from healthcare professionals, while about 30% indicated their source of information was from family or friends. Women taking CHC for period regulation, of Asian race, on a regular exercise program, and who preferred to menstruate monthly were less likely to manipulate their menstrual cycle. The likelihood of menstrual cycle manipulation increase dasfemaleage increased. Women whoused the pill, who preferred to menstruate less than monthly, and who felt fairly knowledgeable about their CHC were more likely to manipulate their menstrual cycle. In conclusion, a significant percentage of university-aged women who use CHC choose to manipulate their menstrual cycle and the characteristics of these women may predict probability of this choice.

Does Spatial Attention Influence the Severity of Visual Crowding?

Presenter: Daniel Klee

Mentor: Edward Awh

PM Poster Presentation

Poster 20

The identification of a target in peripheral vision is severely impaired in the presence of nearby distracting information. This phenom- enon is referred to as visual crowding, and it constrains important visual processes, such as object recognition and reading. Although a popular model of crowding attributes perceptual degradation to the compulsory averaging of target and distractor feature values, recent work by Ester, Klee, & Awh (in prep.) suggests that crowding is the result of feature mislocalization and a subsequent “swapping” of target and distractor feature information. Decades of research have shown that when an observer directs attention to the location of a stimulus, perceptual processing of that item is enhanced. Here, we examined the consequences of spatial attention on visual crowding. Our findings show that spatial attention attenuates crowding effects by reducing confusions between target and distractor values. The critical spacing distance for crowding – defined by the largest distance between targets and distractors where crowding is observed – was unaffected by spatial attention. These findings shed light on the basic mechanisms by which visual attention can ameliorate the harmful effects of nearby distractor stimuli.

Runx2b Transgene Expressing the Peb2A2 Isoform Shows Spatially Restricted Expression in the Developing Zebrafish Craniofacial Skeleton

Presenter: Nathan Johnson

Mentor: April DeLaurier

PM Poster Presentation

Poster 18

Transgenic techniques have revolutionized the study of cellular, developmental, and molecular biology by allowing researchers to visualize the proteins they study in vivo. When expressed in skeletal elements of the zebrafish (Danio rerio), transgenes allow us to explore cell behavior and the genetic pathways involved in craniofacial morphogenesis. Here we discuss a runx2b transgenic line generated with BAC mediated recombination that expresses 1 of 3 runx2b isoforms, pebp2A2. As an early gene in specifying skeletal cell identity, pebp2A2 expression predicts pre-osteoblasts and pre-chondrocytes. Pebp2A2 expression in progenitor cell populations pre-specifies osteoblasts and chondrocytes prior to expression of other known markers in the skeletogenic pathway, such as sp7, the earliest marker of osteoblast identity. Through the use of spinning disc confocal microscopy, we describe pebp2A2’s spatial and temporal expression in specifying osteoblasts and chondrocytes. Understanding the early specification of osteoblasts will allow us to interpret mutants such as the mef2ca mutant – a mutant with ectopic and mis-patterned craniofacial bones. Subsequent research with the runx2b transgenic line will help us to elucidate the role of the runx2b signaling pathway in ossification and patterning the skeleton.

Legislating Identity – Saami Development and Self-Determination in Sweden

Presenter: Bennett Hubbard

Mentor: Yvonne Braun

PM Poster Presentation

Poster 16

The Saami, an ethnic group indigenous to a large portion of land that stretches from Norway into Sweden, Finland, and Russia, have persevered under harsh assimilation regulations enforced by the nation-states in which they have resided in for centuries. While significant improvements have been made, Saami communities within northern Sweden, where some research was conducted, have suffered under legislation that has been deemed “progressive” by the Swedish Riksdag, in which the Saami have no representation. This legisla- tion is both an improvement of previous policies maintained by the Swedish government and yet is still limited in their understanding of Saami identity and culture and presupposes that all Saami communities have the same needs and values. Examples of such legislation include the Reindeer Act of 1971, which recently has served as a catalyst for towns in northern Sweden and the Swedish Supreme Court to forbid Saami reindeer herding in several areas. Industrial growth in northern Sweden has also impacted Saami livelihood and has influenced legal perceptions regarding Saami identity, as shown with Sweden’s reluctance to sign on to ILO Convention 169, which recognizes the rights that indigenous peoples have regarding land use. As such, this legislation of identity has caused much distress for Saami communities, many of which are rural and underdeveloped. This raises questions regarding the role that indigenous peoples have in a democratic society and how legislation can inform those roles.

Invertebrate Species Richness on Deep Cobble and Gravel Bottoms off Cape Arago, Oregon

Presenter: Nick Hayman

Mentor: Craig Young

PM Poster Presentation

Poster 14

Although conservation of marine diversity is a major goal of an ongoing process to establish marine reserves in the Oregon Territorial Sea, virtually all subtidal studies off Oregon have considered only fishes and the largest invertebrates. Using dredge samples, we assembled comprehensive species lists of sessile and motile invertebrates on cobble and gravel substrata between 50 and 70m depths off Cape Arago, Oregon. The species richness on cobble substratum (112 species) was much higher than species richness on gravel sub- stratum (31 species). Species accumulation curves suggest that we found most of the species on the cobble substratum but that more samples would be required to fully assess the cobble community. Sessile invertebrates were more common than mobile invertebrates. The data also showed significant patchiness, as indicated by between-sample differences. This study shows that sea-floor mapping that does not resolve substratum particle size cannot be used to predict richness of the rocky-bottom community.