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The KnowledgeBank at OSU (75.613 recursos)

Knowledge Bank contains collections of presentations, publications and reports related to Ohio State University.

20th Denman Undergraduate Research Forum (2015)

Mostrando recursos 1 - 20 de 71

  1. Construction of a Thermococcus kodakarensis Deletion-Strain Library

    Lin, Jean; Staikoff, Jenna; Angelotti, Austin
    The biological world is divided into three primary Domains, two prokaryotic Domains, the Archaea and Bacteria, and the Eukaryotes. The Archaea were only first recognized late in the 20th century and, at first, proved difficult to investigate due to the lack of genetic systems. This barrier was removed by the discovery in 2003 that Thermococcus kodakarensis, a hyperthermophilic Archaeon, is naturally competent for DNA uptake and genetic recombination. Since then, to take advantage of this discovery, many genetic tools have been developed and we are now constructing a T. kodakarensis deletion–strain library. The genome is predicted to contain 2,306 protein-encoding...

  2. Stability of Total Phenolics and Anthocyanins of Three Types of Black Raspberry Confections During Storage

    Guo, Aina
    Berries are recognized for their health-promoting properties and roles in disease prevention. The major components in black raspberries that have been linked to chronic disease prevention are phenolic compounds, such as anthocyanins, proanthocyanidins and ellagitannins. Of these, anthocyanins are present in the highest quantity and have been studied for their role in prevention of heart disease, cancer and obesity. These phenolic compounds, however, are unstable during storage and can be easily degraded by factors such as temperature, sunlight, oxygen, and enzymes. Moreover, during long-term storage, the anthocyanins can undergo polymerization and form pigments, influencing the color of the products and...

  3. Comparison of the storage stability of starch and pectin black raspberry confections

    Shi, Menghan
    Black raspberries (BRB) are a rich source of bioactive phytochemicals and nutrients, such as anthocyanins and ellagitannins. The phenolic compounds in BRB have drawn much attention recently due to their promising anticancer effect. Physicochemical properties such as texture and water content/activity may influence the phenolic compound stability and sensory acceptance during storage. Therefore, finding suitable food matrix with extended shelf life, higher physicochemical stability and production consistency is important in delivering the bioactive compound from BRB in clinical trials. The objective of this study is to assess the physicochemical stability of two different BRB matrices: Starch and pectin based gummies,...

  4. Quick to be selfish or quick to be kind? Response time asymmetries in social decision making

    Butler, Alison
    Dual-process theories classify a fast, automatic “System I” and a deliberative, controlled “System 2” as distinct mechanisms driving human behavior. Several recent studies have used a classic experimental economics scenario, the public goods game (PGG), to link these systems with participants’ tendency to act cooperatively. This research attempts to measure patterns of intuition and reflection by tracking an individual’s decision time when donating to a common pool. These donations are multiplied by the experimenter and then redistributed equally among the group. Some authors find that cooperative participants make fast decisions, arguing that cooperation is thus intuitive. Meanwhile, other authors find...

  5. Synthesis of pyridine and pyridinium quinone methide precursors: studies towards the realkylation of aged acetylcholinesterase

    Dicken, Rachel
    Acetylcholinesterase (AChE) is an essential enzyme in the human body, which hydrolyzes acetylcholine into choline for biochemical processes. Organophosphorus (OP) nerve-agents such as Sarin, Soman and Tabun are covalent inhibitors of AChE. Following exposure to OPs, inhibited AChE undergoes a subsequent irreversible aging process in which the OP-AChE adduct is de-alkylated (aged) resulting in the accumulation of excess acetylcholine in the central nervous system. Current oxime based pharmaceuticals can only be used to treat the inhibited AChE and are ineffective on the aged AChE. Our research focuses on the design of small molecules that can be used to re-alkylate aged...

  6. Mindfulness and Mind-Wandering in Older Adults: Implications for Behavioral Performance

    Londerée, Allison; Fountain-Zaragoza, Stephanie
    Mind-wandering (MW) is an attentional shift from the task at hand to internally generated thoughts. Although common, MW is associated with decreased performance on tasks requiring sustained attention and executive control. In juxtaposition to MW, mindfulness is attending to the present moment nonjudgmentally. Recent studies of both mindfulness disposition and mindfulness training provide evidence for associations between higher levels of mindfulness and both decreased MW and improved cognitive performance. Interestingly, researchers have found that our tendency to mind wander decreases and mindfulness disposition increases with age. Our study further examines the association between mindfulness and MW in an ageing population....

  7. Influence of a Maternal Dietary Yeast Supplement on Immunoglobulin Concentrations in Foals from Birth to Four Months of Age

    Reddish, John Mark; Cole, Kimberly; Leimbach, Rachel
    Previous studies in multiple species have shown that maternal diet can affect immunoglobulin concentrations in their resulting offspring. To our knowledge, the effect of maternal dietary yeast supplementation on immunoglobulin levels in foals has not been studied. In this study eight Quarter Horse mares (14.5 ± 7.5 yr) were randomly assigned to one of two groups: Yeast or Control. All mares received a control diet of 0.5% BW of a 16% CP pelleted concentrate with water and mixed grass hay ad libitum. Mares in the yeast treatment group also received 1g/45.4 kg of BW/d of a live culture of Saccharomyces...

  8. Social capital and high-risk sexual behaviors in agricultural plantation residents in Tanzania

    Wiles, Melissa
    Human immunodeficiency virus (HIV) and other sexually transmitted infections (STIs) are leading causes of mortality and morbidity in many countries of the world. The practice of having concurrent sexual partners is an important risk factor for STI transmission. Social capital is a target area for improving sexual health. Social capital describes the ways in which individuals are connected to resources that can influence their behaviors, and provides methods of coping with stressors. Previous studies have yielded contradicting findings about the effects social capital has on sexual health behaviors and STI prevalence. Our study aims to investigate social factors, namely social...

  9. The Churches of Kythera

    Crum, Matthew
    This study focuses on the geographic significance of churches constructed on the Greek island of Kythera between the 10th century and mid-16th century. Close analysis of the churches in the northern half of the island shows that these structures, along with their spiritual functions, were often used in tandem with defensive structures or as defensive structures themselves. These religious buildings performed the role of watchtowers, or viglae. This conclusion is based on the geographic relationships between the churches and the villages, roads, and coasts, as well as by the architectural features of several of these sites. This thesis also argues...

  10. The Effects of EPA+DHA Supplements on CRP Levels in Patients with Chronic Venous Leg Ulcers: A Pilot Study in Older Adults

    Sawyer, Jacqueline
    Chronic venous leg ulcers (CVLUs) affect approximately 1% of the U.S. population and nearly 4% of people over age 65 years. The healthcare costs (> 1 billion USD annually) associated with CVLUs and their increasing prevalence support the need for new interventions to facilitate healing. CVLU pathogenesis involves unremitting inflammation. Polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have inflammation resolving effects. This study’s purpose was to compare plasma levels of high-sensitivity C-reactive protein (hs-CRP), an inflammation biomarker, over an 8-week period between CVLU participants in an Active Group receiving EPA+DHA supplements and those in a Placebo Group....

  11. Understanding Pragmatic Language Development: Comparing Adults and Children

    Martinez, Liana
    This study addresses the connection between children’s developing knowledge of prosody – their use of pitch when producing language – and pragmatics – their use of language in plausible ways, to convey and comprehend meaning, whether spoken or unspoken. Previous studies on this topic show that adult comprehension of the quantifier ‘some’ is different when ‘some’ is produced with what we refer to as a “pitch accent” or sudden variation in pitch that indicates a change in meaning. While children have been shown to grasp this difference in meaning, previous work suggests that they attend to word duration and not...

  12. Linkages between physical activity and nightly salivary cortisol in a pilot study of adolescents

    Gresham, Louis
    The purpose of this study was to explore associations between the frequency of moderate/strenuous physical activity among adolescents and their averaged nightly cortisol level collected over a one-week time period. Prior research has supported that physical activity can be beneficial for reducing psychosocial stress. However, studies have also found significant associations between high intensity exercise and elevated salivary cortisol levels– a physiologic stress marker. Secondary data were analyzed from a pilot study of 22 adolescents recruited from one high income and one low-income census tract located in an urban area in the Midwest. Data were collected via trained interviewers over...

  13. Manipulating Attitude Change Toward Michigan Fans by Using Facial Expressions in Evaluative Conditioning

    Fridstein, Allie
    This experiment examined the role of implicit misattribution in an evaluative conditioning (EC) procedure aimed at modifying attitudes toward outgroup members (Michigan fans). EC is attitude change toward an object (conditioned stimulus, CS) due to its pairing with another valenced object (unconditioned stimulus, US). The present research tests the Implicit Misattribution Model (IMM; Jones, Fazio, & Olson, 2009) by examining facial expressions as a factor influencing EC. The IMM proposes that EC occurs when viewers unconsciously misattribute their attitude towards the US to the CS and any factor that promotes confusability regarding the source of the activated evaluation fosters such...

  14. Executive Function’s Role in Children’s Perception of Nonnative Speech

    Hill, Angela
    Large individual differences in spoken word recognition have been observed in children with hearing loss and with normal hearing. Executive functions account for some of this variability (Beer, Kronenberger, & Pisoni, 2011; Lalonde & Holt, 2014). Individual performance differences are also evident when listeners are presented with nonnative speech. This study examined the influence of executive function on children’s nonnative speech perception. Eighty-four 5- to 7-year-old monolingual English-speaking children were presented with 60 English sentences produced by either a native English or Mandarin-accented talker (Van Engen et al., 2010) embedded in multi-talker babble at +8 dB signal-to-noise ratio. For 30...

  15. Design of Leading Edge Vortex Flaps for Delta Wings at Low Speeds

    Wagner, Benjamin
    Small unmanned aerial vehicles (UAVs) have become increasingly important in the role of tactical reconnaissance. Frontline troops rely on the ability to easily deploy UAVs from any position in order to collect time sensitive intelligence. One of the primary criteria for small UAVs is that of portability. In order to address this need, it has been proposed to design a UAV with a foldable delta wing made of a flexible material. However, delta wings typically suffer from decreased aerodynamic efficiency which is the ratio of the lift created to the drag produced. Poor performance in this regard is especially pronounced...

  16. Development of an Active Flight Envelope Warning Method for General Aviation Aircraft

    Scherer, Steven
    Loss of control incidents in flight are the primary cause of fatal general aviation accidents. By definition, a loss of control event is a preventable occurrence where a pilot should have maintained or regained control of their aircraft. Giving a pilot sufficient warning to correct dangerous situations is crucial in preventing loss of control. Existing warning methods are based on physical margins of aircraft limitations and do not directly consider how much time is left to act before loss of control. This research focuses on the development of a method that uses real-time inertial and aerodynamic data to calculate and...

  17. Prevalence and Demographics of Vitamin D Deficiency in Children with Asthma

    Messick, Emily
    Vitamin D promotes calcium and phosphorus absorption from the intestinal tract and exerts anti-inflammatory effects on the immune system. Low vitamin D levels raise risk for autoimmune diseases. Vitamin D deficiency also causes rickets, osteopenia, osteoporosis, and fractures. Since few foods contain it, we are reliant on sun exposure for cutaneous synthesis of vitamin D. Small studies have explored the relationship between asthma and vitamin D levels, but larger controlled studies are needed. This study examines the relationship between demographics and self-reported sun exposure/dairy intake with 25-OH vitamin D levels in asthmatic children, as part of a larger study including...

  18. Optimizing Frequency Channels in Cochlear Implants

    Boyce, Lauren; Holt, Rachael Frush; Nittrouer, Susan; Moberly, Aaron
    Cochlear implants (CIs) are devices used by individuals with hearing loss to improve communication through the use of an electrode array that directly stimulates the auditory nerve. Existing signal processing strategies utilize a logarithmic frequency-to-electrode allocation, mimicking the representation of frequencies along the basilar membrane (high frequencies at the base and low frequencies at the apex). These strategies support some degree of open-set speech recognition for CI users; however, average speech recognition remains well below what normal-hearing adults are capable of. To enhance speech recognition in adult CI users, this study examined one promising alternative to the standard logarithmic frequency-to-electrode...

  19. Analyzing Semantic-Pragmatic Processing of Scalar Implicatures in Typically-Developing Children

    Selio, Emily
    This research examines the presence of the quantifier “some” in English speech. Past research indicates that both semantics and pragmatics, or the context of the situation dictate the meaning of the word. With this particular quantifier it is important to identify the variations in pitch accent that will be controlled for within this experiment. The first vowel-reduced sm implies an existential or “logical” interpretation of the implicature. This can be interpreted as a “some and maybe all” meaning. Another, spoken with a L+H* pitch accent, SOME, has a pragmatically influenced “some, but not all” implicature. The final variation, some, holds...

  20. Numerical Magnitude Representations Explain the "Learning Gap"

    Wang, Yiwan
    The mathematical “learning gap” between Chinese and American students exists since a very young age. Previous studies have focused on the correlations between children’s arithmetic performance and their general intelligence, symbolic numerical proficiency (e.g., the numerical number “4”), or non-symbolic numerical proficiency (e.g., four apples) within a single culture. The current study has two hypotheses: 1) Chinese preschoolers perform better in math than American preschoolers; and 2) Chinese children’s outperformance is because of their higher symbolic numerical proficiency. We sampled 80 children, 40 native to China and 40 native to America. The arithmetic performance was measured by the 1-minute speed...

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