25th Hayes Graduate Research Forum (March, 2011)

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1st Place: Harrison, Jane
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2nd Place: Chang, Woong Jo
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3rd Place: Blasenak, Andrew
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Biological Sciences
1st Place: Anthony, Bryan
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2nd Place: Sullivan, Brandon
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3rd Place: McClory, Sean
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1st Place: Easwar, Karthik
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2nd Place: Zhong, Bijuan
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3rd Place: Dachner, Alison
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Education and Human Ecology
1st Place: Marchionda, Daria
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2nd Place: Rector, Meghan
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3rd Place: Kotila, Letitia
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1st Place: Ericson, Tristan
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2nd Place: Jamison, Steve
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3rd Place: Splittstoesser, Riley
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Food, Agricultural, and Environmental Sciences
1st Place: Card, Marcella
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2nd Place: Simmons, Amber
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3rd Place: Atnip, Allison
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1st Place: Kock, Stacia
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2nd Place: Steward, Tyran
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3rd Place: Patterson, Lindsey
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Math and Physical Sciences
1st Place: Pejcha, Ondrej
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2nd Place: Philibert, Gwenaelle
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3rd Place: Chatterjee, Chandrani
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Professional Biological Sciences
1st Place: Williams, Jessica
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2nd Place: McClory, Susan
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3rd Place: Oaks, Joshua
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Social and Behavioral Sciences
1st Place: Parker, Jeffrey
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2nd Place: Fine, Leigh E.
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Poster Division: Arts, Humanities, and Social Sciences
1st Place: Vincent, Pamela
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2nd Place: Anzeljc, Samantha
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3rd Place: Lee, Meghan
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Poster Division: Biological Sciences
1st Place: Abbaoui, Besma
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2nd Place: Jarrett, Brant
3rd Place: Fenn, Ashley
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Poster Division: Engineering, Math, and Physical Sciences
1st Place: Govindarajan, Harish
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2nd Place: Ayvaz, Huseyin
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3rd Place: Park, Sung Hee
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Recent Submissions

Now showing 1 - 20 of 38
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    Effects of Processing on the Oxidative Stability of Docosahexaenoic Acid Oil
    (2011-03) Atnip, Allison; Min, David
    Docosahexaenoic acid (DHA) is an omega-3 fatty acid which is essential for normal brain and retinal development. A deficiency in fetal cerebral DHA content has been associated with preterm delivery, which may lead to higher risks for autism, ADHD, and schizophrenia. Western diets are deficient in DHA intake, making the development of DHA-enriched products a growing facet of the food industry. The poor oxidative stability of DHA has made the development of such products challenging, as the oxidation is rapid and produces off-odors and flavors, making the product unacceptable to consumers. Effects of refining, bleaching, winterizing, and deodorizing on the oxidative stability of DHA (22:6 Ω-3) oil were studied by a combination of headspace oxygen depletion (HOD) by gas chromatography and total volatile compound formation by SPME-GC. Results for both showed that refined oil was significantly (p < 0.05) less stable than bleached, winterized, and deodorized oils. The oxygen content in the refined, bleached, winterized, and deodorized DHA oil samples decreased from 20.9% on Day 0 to 6.7%, 8.3%, 7.8% and 7.8%, respectively on Day 5. The bleached, winterized, and deodorized oils were determined not to be statistically different from each other (p > 0.05), however the refined oil showed significantly more HOD (p <0.05), corresponding to a lower oxidative stability. Refined, Bleached, winterized, and deodorized oils showed average volatile compound formations over 5 days of storage of approximately 4,041,000 electronic counts (ec), 482,100 ec, 437,200 ec, and 405,800 ec, respectively. The refined samples again showed significantly (p < 0.05) higher volatile compound formation, corresponding to a lower oxidative stability. The bleached, winterized, and deodorized samples were not significantly different from each other (p > 0.05). Bleaching proved to be the crucial processing step in increasing the oxidative stability of DHA oil. Optimizing the bleaching process may be an important first step in increasing the oxidative stability of DHA oil.
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    Dynamic Trunk Control Influence on Run-to-Cut Maneuver: A Risk Factor for ACL Rupture
    (2011-03) Jamison, Steve; Chaudhari, Ajit
    ACL rupture is one of the most common serious knee injuries in field and court sports, with an estimated 70% of these being non-contact in nature, often from sudden changes in direction or pivoting. Previous studies have shown that knee abduction and tibial internal rotation moments independently strain the ACL. In collegiate athletes, deficits in dynamic trunk control, measured during an isolated trunk perturbation test, have been correlated to knee injury incidence. The goal of this study was to determine if dynamic trunk control during a run-to-cut maneuver was correlated to the dynamic loading of the knee during the same activity. Thirty healthy subjects performed an unanticipated 45° run-to-cut in the laboratory, planting on their dominant leg. Markered motion capture techniques and inverse kinematics were used to calculate torso angle relative to vertical (outside tilt), torso angle relative to ground reaction force (torso-GRF) and peak knee abduction moment (pKAM) for three trials for each subject. Normalized knee abduction moments were log transformed to meet normality assumptions of the statistical models. A linear mixed model was used to determine the association between log transformed pKAM (Y) and each torso angle (X), with approach speed, cutting angle, and gender considered as covariates. Significant positive associations were found between the log transformed pKAM and outside tilt (p=0.009) and torso-GRF angle (p=0.029). These results suggest that an increased lean, in the frontal plane of the shoulders, away from the cutting direction and away from the GRF would increase peak knee abduction moment, thereby influencing ACL injury risk. Increased lean during an unanticipated task may be an indication of poorer dynamic trunk control or flawed control strategy and should be investigated in future studies.
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    Development of a Primary Care Clinician Intervention in the Management of Overweight and Obesity in Children and Adolescent: A Pound of Cure
    (2011-03) Anzeljc, Samantha
    Primary care clinicians, despite regular access to young families, lack a cohesive model for approaching office visits regarding excess weight. Using the 2007 Expert Committee’s Recommendations, a set of clinician guidelines on the standard of care for managing childhood obesity, we developed high quality intervention tools for clinician use to direct behavior modification in families with school-age children. We have developed “A Pound of Cure” (POC), a counseling process and educational materials founded on the ECRs, to provide clinicians with the necessary skill set to approach excess weight in children. POC modular counseling sessions and resources were piloted among physicians in a primary care network. Families and physicians were interviewed on the modular counseling sessions and resources. The feedback obtained guided development of office visit modules and materials. On average, motivated families that returned to the clinic needed to complete only 3 to 4 modules, setting 3 goals per visit, to successfully incorporate the recommendations into the child’s daily life. Of families that returned for follow up visits 38.5%, 47.3%, 8.7%, 5.2%, and 1.7% of families completed two, three, four, five or six office visit modules, respectively. Weight maintenance or weight loss occurred in 57% of patients, with an average weight loss of 1.0 kg.
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    What Do Fathers Do? A look into the daily activities of fathers versus mothers using time diary data
    (2011-03) Kotila, Letitia; Kamp Dush, Claire
    This study compares levels of mother and father involvement within activity categories that include engagement, responsibility, and childcare, across the transition to parenthood for dual-earner, first time parents. Findings indicate that while fathers are very involved with their children, there remain significant discrepancies in the amount of time mothers spend participating in childcare activities for their children. Implications of these findings and directions for future research are discussed.
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    Activated microglia from aged mice are less sensitive to anti-inflammatory feedback from IL-4
    (2011-03) Fenn, Ashley; Godbout, Jonathan
    Aging is associated with increased inflammatory conditions both peripherally and centrally. Our lab has previously shown that microglia, innate immune cells of the central nervous system, become primed and reactive as a function of age. Following an inflammatory stimulus these primed microglia show exaggerated and prolonged activation associated with an extended sickness response and induction of depressive-like behavior. The purpose of this study was to identify a mechanistic cause for prolonged microglial activation following immune challenge. We report that following a peripheral injection of LPS, microglia from adult mice upregulate both inflammatory (M1) and anti-inflammatory (M2c) gene expression, extending our knowledge of the M2b monocyte phenotype. Furthermore, we demonstrate that activated microglia from aged mice show exaggerated expression of M1, M2a, and M2c related genes, rather than a definitive shift towards M1. Protein expression of the receptors for IL-10 (IL-10R1) and IL-4 (IL-4Rα) were assessed on microglia of adult mice following treatment with LPS. Microglia showed marked upregulation of IL-4Rα after LPS treatment, whereas expression of IL-10R1 did not change. Furthermore, activated microglia from aged mice failed to upregulate IL-4Rα. Treatment of activated microglia ex vivo with IL-4 promoted a down-regulation of M1 related gene, inducible nitric oxide synthase (iNOS) and an upregulation of M2 related gene, Arginase I (Arg) following LPS treatment in adult mice. Activated microglia from aged mice, however, maintained high levels of iNOS gene expression, though they still promoted Arg expression. Taken together, these results indicate that activated microglia from aged mice show impairments in the receptor and cell signaling pathways necessary for anti-inflammatory feedback from IL-4.
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    Atomic Scale Modeling of the Effect of Irradiation on Silica Optical Fibers
    (2011-03) Govindarajan, Harish; Windl, Wolfgang
    Optical fibers and optically-based sensors find extensive use in instrumentation and control systems in nuclear power plants due to their desirable characteristics and advantages over traditional electrical transmission systems, such as immunity to electromagnetic interference (EMI). Vitreous silica which has a high melting point (~1650°C), is a suitable material for optical fiber and sensor applications within high-temperature reactor pressure vessels. However, although pure vitreous silica-core fibers are transparent over a broad spectrum (ultraviolet to near infrared), irradiation causes the optical fibers to “darken” and form “color centers”. This leads to preferential absorption of light at frequencies specific to the defect type, resulting in the attenuation of signals, and is a major concern for these applications. While abundant experimental information exists on the various defects in silica and their corresponding optical properties, there still needs to be an accurate and predictive modeling approach that can provide useful information about defect evolution in the structure and crystallization effects upon heating and irradiation, and establish the correlation between the local structural defects caused by irradiation to optical transmission losses over typical lengths of the fiber. This paper presents a computational approach using molecular dynamics calculations to simulate irradiation damage, a set of techniques to extract and correlate the structural defects thus created, and ab-initio electronic structure calculations with Hybrid Density Functional Theory (DFT) methods to model the effect of the structural defects on the electronic and optical properties.
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    Lexical Ambiguity in Evolutionary Discourse: Implications for Teaching, Learning, and Assessment
    (2011-03) Rector, Meghan; Nehm, Ross
    This study investigates lexical ambiguity in evolutionary discourse and explores the implications of such language for teaching, learning, and assessment. Specifically, this study investigated what students' mean when they use five terms that commonly occur in evolutionary explanations: pressure, select, adapt, need, and must. The study employed a new technological tool known as the Assessment Cascade System (ACS) to investigate the frequency with which undergraduate biology majors spontaneously incorporate lexically ambiguous language in evolutionary explanations, as well as their definitions and explanations of what they meant when they used such terms. Among the 1282 initial responses, 81% of students spontaneously used a multivalent term at least once in evolutionary explanations. Moreover, the majority of these initial responses were judged to be scientifically inaccurate, and accurate use of some terms was significantly correlated with students' course grade. While the scientific accuracy of the majority of student responses remained the same from initial to follow-up, a sizable minority of student response did not. Responses that were initially ambiguous were more likely to be resolved by use of the ACS follow-up prompts, resulting in an increased understanding of students' evolutionary explanations.
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    (2011-03) Kock, Stacia; Keating, Christine
    Using feminist theory as a background, this study explores the relationship between citizenship and economic identities, specifically looking at how those living in poverty define citizenship. Whether political or social in nature, citizenship as both an identity and a political construct influences the lives of all Americans. Feminist theorists (Jaggar, 2006; Kymlicka & Norma, 1994; Lister, 1997; 2003; Young, 2000) have long argued that citizenship excludes certain individuals on the basis of gender, racial, sexual, economic, and national identities. Yet, as this study aims to explore, do those who are thought to be excluded from citizenship understand themselves as excluded? In order to investigate the materiality of the theoretical claims of citizenship’s exclusivity, this study turns to the perspectives of antipoverty activists from two Midwest-based organizations. Pulling from interview data, this paper explores how the participants define citizenship in their own words and whether they aspire to create a more inclusionary approach to citizenship for low-income individuals.
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    Small Arts Organizations: Supporting their Creative Vitality
    (2011-03) Chang, Woong Jo; Wyszomirski, Margaret
    This paper examines how to support the creative vitality of small arts organizations. It incorporates the Multiple Case Narrative on arts administrators at 13 selected small arts organizations and cross-references it with an in-depth case study on an emerging theatre. Highlighting the significant role of SAOs in the arts world, it explores the dynamic ecology of SAOs by focusing on the three key levers that move SAOs along the balancing point between their mission and their money in order for them to maintain their creative vitality: (1) Leadership/Entrepreneurship, (2) Technology, and (3) Support Systems. Conclusively, emphasizing that size consideration for arts organizations is of utmost importance for the creative vitality of SAOs, this paper suggests appropriate and affordable ways to support SAOs so that they can sustain themselves in the challenging environment of the arts world.
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    In Vitro and In Vivo Inhibition of Human Bladder Cancer by Broccoli Isothiocyanates: Characterization, Absorption, Metabolism and Interconversion
    (2011-03) Abbaoui, Besma; Clinton, Steven
    Transitional cell carcinoma of the urinary bladder is the fifth most common neoplasm and the twelfth leading cause of cancer death in the United States. In addition, bladder cancer is estimated to be the most expensive cancer to treat with $3.7 billion in direct costs and is of growing concern due to the expansion of global tobacco use, the main etiologic risk factor. There are two differing variants of this disease: a superficial and an invasive type. Epidemiologic evidence suggests that consumption of a diet rich in cruciferous vegetables, particularly broccoli, is associated with a lower bladder cancer risk. These vegetables contain high concentrations of glucosinolates (GLUs) that are enzymatically hydrolyzed to bioactive isothiocyanates (ITCs) by myrosinase. There is growing evidence that isothiocyanates have anti-cancer effects. Here, we first quantified glucosinolates and isothiocyanates found in broccoli and broccoli sprouts and showed evidence that broccoli and broccoli sprout isothiocyanate extracts can significantly inhibit both non-invasive (RT4) and invasive (J82, UMUC3) forms of human bladder cancer cells, with broccoli sprouts having significantly higher inhibition due to their higher ITC content. Of all the ITCs found in highest concentration in broccoli sprouts, sulforaphane (SFN) and erucin (ECN) have the greatest efficacy in inhibiting both non-invasive and invasive human bladder cancer cells, followed by allyl ITC and then iberin. In addition, normal human urothelial cells are less sensitive to the inhibitory effects of SFN and ECN followed by RT4, J82 and then UMUC3. SFN and ECN are shown to induce cell cycle arrest of both non-invasive and invasive bladder cancer cells in the G2/M phase. There is also a significant induction of apoptosis, as indicated by PARP cleavage and caspase 3/7 activity along with a downregulation of survivin protein. Next, we translated our in vitro findings in vivo utilizing a xenograft model with female athymic nude mice injected with 5 X 105 UMUC3 cells in both flanks. Mice were treated with either 4% freeze-dried broccoli sprouts, 2% freeze-dried broccoli sprouts extract; or gavaged daily with 295 µmol/kg sulforaphane or 295 µmol/kg erucin; for two weeks (n=12/group). Tumor weight of all treated groups was significantly lower than control (40% reduction or greater). A significant decrease in cell proliferation (Ki67) and induction of apoptosis (PARP) was observed in the broccoli sprout treated group. Absorption and bioavailability of sulforaphane and erucin metabolites was determined in mouse plasma by UPLC-MS/MS. Metabolites of sulforaphane and erucin were absent in control mice and present in plasma of all treated groups, with dietary and pure phytochemical treatments, resulting in similar plasma metabolite concentrations (micromolar range). N-acetyl cysteine conjugates were found at highest concentrations, followed by cysteinyl and glutathione conjugates and small amounts of detectable cysteinyl glycine conjugates and free SFN. Evidence of inter-conversion of sulforaphane and erucin was seen. Collectively, our data shows that broccoli isothiocyanates are readily absorbed and metabolized in the mouse and can inhibit human bladder cancer in vitro and in vivo. This supports further preclinical and clinical studies to determine broccoli isothiocyanates potential to help ameliorate the bladder cancer burden.
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    Pharmacologic Restoration of PP2A Activity by FTY720 as a Novel Therapy for Polycythemia Vera
    (2011-03) Oaks, Joshua; Perrotti, Joshua; Perrotti, Danilo
    Polycythemia Vera (PV) is an incurable rare myeloproliferative disorder driven by Jak2 V617F with few viable treatment options and no curative therapy available. With the intention of developing a curative treatment modality, we examined the interplay between the known tumor suppressor PP2A and the driver of PV, Jak2 V617F. We found PP2A to be inactivated by Jak2 V617F activity and that forced PP2A activity is produces a loss of Jak2 V617F activity and function. Of particular interest we found that the clinically relevant PP2A activator/immunosuppressant FTY720 (2-amino-2-[2-(4-octylphenyl)ethyl]-1,3-propanediol hydrochloride, fingolimod, Gilenya) to activate PP2A in PV model cell lines and primary patient samples. Treatment with FTY720 produced a reduction in Jak2 protein coupled with reduced cellular proliferation in cells expressing Jak2 V617F. The anti-leukemic effects of FTY720 were found to be independent of immunosuppressive activity. To conclude, we found that PP2A activation in cells expressing Jak2 V617F by FTY720 reduced Jak2 levels and proliferation and did so in a mechanism independent of immunosuppression.
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    Parenting Perfectionism as a Predictor of Parental Adjustment
    (2011-03) Lee, Meghan; Schoppe-Sullivan, Sarah
    Perfectionism is conceptualized as the extent to which an individual holds excessively high standards for themselves, and is thought to be multi-dimensional, consisting of maladaptive and beneficial aspects. This paper aimed to examine the new construct of parenting perfectionism, defined as perfectionism specific to the parenting role, through two dimensions: self-oriented, or personal desire for perfection, and societal-oriented, or perceived societal expectations for perfection. Using longitudinal data from a sample of 182 dual-earner couples at the transition to parenthood, as part of the New Parents Project, I investigated the association between parenting perfectionism and parental adjustment. Results indicate that for mothers, societal-oriented parenting perfectionism was associated with reduced parenting self-efficacy; however, self-oriented parenting perfectionism was associated with increased satisfaction with the parenting role. For fathers, societal-oriented parenting perfectionism was associated with higher parenting stress, whereas higher levels of self-oriented parenting perfectionism were associated with increased parenting self-efficacy, less parenting stress, and more satisfaction with parenting. In sum, societal-oriented parenting perfectionism had adverse associations with early parental adjustment, whereas self-oriented parenting perfectionism had beneficial associations with parental adjustment, especially for fathers.
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    Word Frequency and Processing: Why the Brain Stores Some Words Whole and Others in Parts
    (2011-03) Parker, Jeffrey; Sims, Andrea
    In this study I show evidence which suggests that how often a word occurs is instrumentally important in understanding how the mind stores and processes words; moreover, I suggest that the mind uses a previously undiscussed process of stripping parts from frequent complex words to recognize simpler and less frequent words found therein. This suggests an important interaction between word frequency and the structure of word storage in the mind. When processing a word, several factors affect how the word will be processed. For example, does the word contain multiple parts like govern-ment or is the word simple like govern? Research into processing of complex words, e.g. govern-ment, has focused on two opposing methods of access: storage and parsing (breaking the word into smaller meaning bearing parts). Most morphological theories assume that morphologically simple bases like govern and discern are stored, as are meaning bearing parts like -ment. Complex words such as govern-ment and discern-ment are therefore believed to be accessed by stripping -ment from the base and computing the meaning based on the two parts (Taft and Forster 1975). However, Hay (2001) argued that this story is incomplete, since words can differ greatly in how frequent they are compared to other related words. For example, government occurs over 107 times more often than govern in the British National Corpus, a collection of 100 million words of English text. On the other hand, discernment occurs only 0.22 times as often as discern. Hay (2001) showed that words that are more frequent than their bases, e.g. government, are likely to be stored as a whole unit. Conversely, complex forms that are less frequent than their bases, e.g. discernment bias towards being broken into parts during processing. Thus, infrequent complex words like discernment are dependent upon their bases in a way that frequent complex words like government are not. Various studies have validated and extended this hypothesis (Hay and Baayen 2002, Taft 2004). While these studies make predictions for how we process words like government, they are silent about how storing these words might affect their morphologically simpler but less frequent bases like govern. In other words, what happens to govern if its complex counterpart government is not dependant on it during processing? In particular, previous work neglects to consider whether less frequent bases like govern should become dependent on their more frequent derivatives like government for access. We might expect this to be the case, based on the prominent role frequency plays in processing. To test the possibility that simple words like govern are dependant of their complex counterparts like government I conducted a lexical decision task with 17 native speakers of Russian. Russian was used because of its rich morphological resources. During the task speakers were visually presented words and were asked to push a ‘yes’ button if the word was real or a ‘no’ button if the word was not. Fake words were intermingled among real words to ensure participants made a decision for every word. Reaction times were measured for each decision. For the words in question, a priming word was shown for 40 milliseconds before the target word appeared. For example, government might be shown before govern. If a word is dependant on another word for processing, a prime will facilitate processing. If the word is accessed independently there will be no facilitation from the prime. Priming was tested in all possible related combinations of simple/complex and frequent/infrequent. My results support previous research in that simple frequent words like discern facilitate the processing of less frequent words like discernment. This supports the explanation that discernment is being accessed in parts, discern + ment. My results also show that complex frequent words like government are stored independent of their bases, i.e. govern does not facilitate the access of government. Interestingly, the opposite was not true because words like government did facilitate the access of their simple infrequent bases like govern. This suggests that even though it is more complex, government acts as the base for govern. This result is striking because no previous study or analysis has suggested that complex words might serve as the base for a simple word during processing. To model this result I posit that the brain is undergoing a subtractive process when accessing these words. For example, as we can say that discernment is processed as discern + ment, we can say that govern is processed as government - ment. Though it has never been suggested for lexical processing, subtractive processes are not unrecognized in linguistics. For example, it is argued that the French feminine adjective blanche ‘white’ is the base of its masculine counterpart blanc (Haspelmath 2002). Likewise in English the word commune was formed by a mistaken analysis of community as complex, i.e. commune + ity, though such is historically inaccurate. Therefore, my proposed model has both theoretical support as well as experimental significance. In summary I show that not all words are stored equally in the mind. Words which are simple and infrequent are dependent on their complex counterparts during processing. To model this innovative finding I suggest that the mind uses a subtractive method during access of these words. This proposed model constitutes a significant contribution to our understanding of how (and what) the brain stores and processes during lexical access.
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    Insights into the faithful translation of the genetic code by the ribosome
    (RNA Journal (Publication of the RNA Society), 2011-03) McClory, Sean; Fredrick, Kurt
    In order to synthesize functional proteins from mRNA, the ribosome must correctly pair each 3 base mRNA codon with the corresponding 3 base anticodon of the cognate (correct) aminoacyl(aa)-tRNA. While this process largely depends upon codon-anticodon base-pairing, the ribosome’s job is complicated by the fact that there exists a large cellular pool of near-cognate aa-tRNAs capable of forming partial matches with the codon being translated, and these vastly outnumber cognate aa-tRNAs. The ribosome maintains high accuracy during translation by breaking the aa-tRNA selection process into two phases, initial selection and proofreading, increasing the accuracy by providing two opportunities for near-cognate aa-tRNA to be rejected. These two phases are separated by the irreversible hydrolysis of GTP by elongation factor (EF)-Tu, which delivers the aa-tRNA to the ribosome. Many potent antibiotics target aa-tRNA selection and increase translation errors. To investigate the mechanism of aa-tRNA selection we used a genetic screen to isolate 34 mutations in the 16S ribosomal (r)RNA that increase translation errors. These mutations cluster around the periphery of the shoulder domain of the small 30S ribosomal subunit, suggesting that a conformational change in this domain is critical for aa-tRNA selection. In vitro, these mutations increase the rate of EF-Tu GTP hydrolysis, similar to error inducing antibiotics. The locations of many mutations are distinct from the binding sites of these antibiotics and may suggest additional areas for drug targets. These findings challenge several conventional beliefs about the mechanism of this ubiquitous process. Additional characterization of these mutations may provide new insights into how the ribosome maintains the accuracy of translation.
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    Evidence for a step-wise program of T cell development within the human tonsil
    (2011-03) McClory, Susan; Caligiuri, Michael
    Human T cell development within the thymus is a well-characterized event, and it is known that a functional thymus is required for normal T cell generation to take place. Individuals with poor thymic function, from either congenital abnormality or post-natal injury, have a difficult time mounting a proper immune response and suffer from debilitating immune deficiency. Thus, it would be highly beneficial to identify an extrathymic human tissue that can support T cell differentiation so that we may eventually augment T cell production in these individuals. However, to date, no definitive site of extrathymic T cell development has been established. In this study, we used flow cytometry to identify five populations of putative extrathymic T cell precursors within the human pediatric tonsil. These populations range from an early CD34+CD38dimLin- subset all the way to a CD1a+CD4+CD8+CD3+/- double positive pre-T cell. Each subset identified phenotypically resembles the same population found in the human thymus, suggesting that there is considerable similarity between the cells in each of these two tissues. Furthermore, each putative extrathymic T cell developmental intermediate found within the tonsil retains the ability to develop into a mature CD3+ T cell. Thus, our data suggest that the human tonsil contains a full spectrum of T cell developmental intermediates that are remarkably similar to those found in the human thymus, and that the tonsil may be an extrathymic site which supports complete T cell differentiation.
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    As Though Heard from Afar: Score Indications in Debussyste Compositions
    (2011-03) Harrison, Jane; Fosler-Lussier, Danielle
    Since their advent in musical scores during the sixteenth century, composers have used dynamic markings (symbols based on Italian words that conveyed relative volume levels such as the abbreviation p for piano, or soft) and performance indications (more lengthy descriptions of the desired speed, style, or timbre of sound) with increasing frequency and precision. Around 1900 the debussyste composers continued the trend of increasing use and finer nuance of directions in musical scores, but in a unique way. They strongly favored the soft side of the dynamic spectrum and performance indications calling for delicate sounds, such as lointain (far off), perdendo (dying out), très doux (very soft), le plus p possible (as quiet as possible), and à peine (barely audible). These distinguishing and pervasive directions written into their musical scores indicate that Debussy and the composers influenced by him were inspired by similar aesthetic goals. I extract the most common poetic indications in the piano scores of Debussy and Maurice Ravel, two of the most influential debussystes, and situate them as well as the predilection for soft and subdued pieces in aesthetic and philosophical trends of the time. The roots of this stylistic practice trace back to the slightly earlier theories of Francophone Symbolists such as Stephan Mallarmé, Albert Samain, and Maurice Maeterlinck, who sought to create delicate atmospheres of monotony and melancholy, because it was an artist in this state and free of superfluous emotional extremes that could produce the most authentic translations of the soul, or interior mental life. Drawing upon the insights of Jann Pasler and Jessie Fillerup, I further suggest that the debussystes’ musical style responded to theories about the functioning of the human mind that were formulated around 1900 by philosophers such as Henri Bergson and Charles Henry. I argue that the debussystes portrayed in their compositions both philsophers’ descriptions of the mind, which were widely known among artists in early twentieth-century France, and that score indications helped to accomplish this. Scholars have long noted Debussy’s predilection for soft dynamics and melancholy themes, but have not accounted for them. My research explains why Debussy was so attracted to soft as well as slow sounds, and it reveals that his novel score indications inspired dozens of other French composers, who were similarly fascinated by the glimpses into the human mind offered by Symbolist literature and contemporaneous philosophy.
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    Characterizing Vegetable Tissue Under Elevated Pressure Using In Situ Electrical Conductivity Measurement and Instrumental Analysis
    (2011-03) Park, Sung Hee; Balasubramaniam, V.M. (Bala)
    A study was conducted to investigate the pressure-induced textural changes in selected low acid vegetable samples (carrot, potato, and red radish) using in situ electrical conductivity measurements. In situ electrical conductivity of the vegetable samples, as a function of pressure and holding time at 25ºC, was recorded every 30 s for 10 min under elevated pressures (200, 400, 600 MPa) using a custom made electrical conductivity cell. Pressure treatment increased electrical conductivity values of all the processed samples as a function of target pressure and holding time up to a certain threshold level. Beyond this threshold level, the electrical conductivity values did not change further. The tissue disintegration index (Z) was calculated based on the in situ electrical conductivity data of the vegetable samples under pressure and those of raw samples. Sample hardness and stiffness were evaluated using an instrumental texture analyzer, and then calculated to a crunchiness index (CI). The relationship between Z and CI was investigated with empirical model fitting of the first and second polynomial. Z and CI had an inverse relationship within the range of experimental conditions studied. In situ electrical conductivity measurement was a useful tool to document the extent of vegetable tissue damage during high pressure processing.
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    Human Growth, Environmental Stress, and the Costs of Reproduction
    (2011-03) Vercellotti, Giuseppe; Stout, Samuel D.
    Variation in height and body proportions is relatively well understood at the inter-population level, but less is known about variation within groups. This study explores intra-population variation in body proportions among 172 (88 female; 84 male) rural Amazonians. The following hypotheses were tested: 1) stunting is associated with changes in body proportions; 2) males and females respond differently to similar environmental stressors and 3) female growth is negatively affected by the costs of reproduction. Height, sitting height and total leg length were examined in different population subsamples in relation to biocultural factors. Differences in proportions were examined using the Quick-Test (Tsutakawa and Hewett, 1977) on Reduced Major Axis regression plots; correlation analyses were employed to detect associations between anthropometric data and female reproductive history parameters. The results indicate that growth was more compromised among females rather than males, as proven by the existence of significantly different body proportions between sex subsamples (p = 0.01). Specifically, females tended to have relatively shorter legs than males. Within sex samples, stunting was not associated with significant changes in body proportions among males (p = 0.50), while significant differences were found among females (p = 0.01). The differences were due to relatively shorter legs among stunted individuals, in agreement with expectations. Among all reproductive history parameters, only age at first birth was significantly correlated with the anthropometric variables. Specifically, positive correlations were found between age at first birth and height (r = 0.29; p = 0.01), and age at first birth and total leg length (r = 0.41; p = 0.001). Biocultural information and analyses’ results suggest that the less desirable growth outcome in females may be due to the costs associated with reproduction. In particular, early female reproduction appears to compromise growth by increasing nutritional stress (due to the energetic costs of pregnancy and lactation) and impeding catch-up growth. This is the first study that reports the long-term impact of early reproduction on women’s growth outcome. Given the increasing number of adolescent pregnancies, especially among disadvantaged groups, these results stress the importance of providing proper attention and care to adolescent mothers to attenuate growth retardation and its associated health risks.
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 Session Communications
    (2011-03) Marchionda, Daria; Slesnick, Natasha
    This paper provides evidence to support the efficacy of Ecologically Based Family Therapy in increasing parental direct communications within 6-8 sessions. It also provides some support to show that EBFT results in a slightly significant decrease in parental indirect communications. In addition, this paper also examines the change in within session communications, both indirect and direct, for the adolescent. To test this, this study utilized transcripts from seven families (n=7) who participated in EBFT. Two time points were utilized to monitor change; the first point was session 1, 2 or 3 and the second point was session 6,7, or 8. Transcripts were coded for parental and adolescent direct and indirect communications using the Living in Familial Environments (LIFE) code. Statistics were done on the codes and analysis showed significant results with parental direct communications, slightly significant results with the parental indirect communications, and no significance in either the adolescent direct or indirect communications. Future research is needed to assess the adolescents’ change in positive and negative communications across therapy.
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    The effect of soy addition on the satiety, glycemic index, and insulinemic index of a soft pretzel
    (2011-03) Simmons, Amber; Vodovotz, Yael
    The contribution of calories from nutrient-poor snack foods is rising in many Western diets, possibly contributing to the increasing prevalence of obesity and diabetes. Soy offers unique potential to provide high quality protein, dietary fiber, and phytochemicals to snack foods to produce a more healthful nutritional profile. In this study, 27.3% of wheat flour was replaced with soy ingredients in a soft pretzel in order to observe the changes in the product's satiety, glycemic index (GI), and insulinemic index (II). First, the soy pretzel was tested for consumer acceptability by 51 untrained sensory panelists on a 9-point hedonic scale. Second, in a crossover trial, 20 healthy adults consumed soy and traditional pretzels (1000 kJ or 239 kcal each) after an overnight fast. They reported their levels of satiety on a 10 cm visual analogy scale (VAS) for 2 hrs postprandially. Third, 12 healthy, non-diabetic subjects consumed soy or traditional pretzels (50 ± 2 g available carbohydrates) to determine the GI and II of both products. Blood glucose and insulin responses were monitored for 2 hrs after consumption and compared to a glucose reference. It was found that the consumer-acceptable soy soft pretzel has a lower GI than its 2 traditional counterpart [39.1±20.4 (mean±SD) for soy and 66.4±15.3 for wheat, p=0.002]. On the other hand, soy addition did not statistically affect II (p=0.15), or satiety (p=0.91). In conclusion, a soy pretzel formulation with 27.3% of wheat flour replaced by soy ingredients leads to attenuated postprandial glycemia without significantly affecting insulinemia or satiety in healthy adults.