30th Hayes Graduate Research Forum (February, 2016)

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Arts
1st place: Sarkar, Kaustavi
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2nd place: Kopyt, Joe
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3rd place: Warrenburg, Lindsay
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Biological Sciences
1st place: Heisler, David
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2nd place: Pitarresi, Jason
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3rd place: Prajzner, Scott


Business
1st place: Teeny, Jacob
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2nd place: Sharma, Luv
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3rd place: Doyle, Sarah
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Education and Human Ecology
1st place: Gibbs, Todd
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2nd place: Head, Samuel
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3rd place: Settle, Theresa
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Engineering
1st place: Lee, Kil Ho
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2nd place: Liu, Bert
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3rd place: Borchers, Tyler
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FAES
1st place: Vrisman, Claudio
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2nd place: Yang, Xu
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3rd place: Sheets, Johnathon


Humanities
1st place: Fry, Zachery
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2nd place: Barber, Cary
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3rd place: Kong, Xueying
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Math and Physical Sciences
1st place: Lao, Ka Un
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2nd place: Li, Shirley
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3rd place: Shrestha, Sweta
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Professional Biological Sciences
1st place: McKim, Daniel
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2nd place: Denton, Nicholas
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3rd place: Reiff, Sean
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Social and Behavioral Sciences
1st place: Freis, Stephanie
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2nd place: Gertz, Evelyn
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3rd place: Ralston, Rachel
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Poster Division: Arts, Humanities and Social Sciences
1st place: Bose, Debangana
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2nd place: Goodfellow, Molly
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3rd place: Baczeski, Lillianna Marie
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Poster Division: Biological Sciences
1st place: Cisse, Yasmine
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2nd place: Witcher, Kristina
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3rd place: Bunker, Helen


Poster Division: Engineering, Math, and Physical Sciences
1st place: Boone, Caitlin
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2nd place: Bennett, Molly
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3rd place: Binkley, Katja


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Recent Submissions

Now showing 1 - 20 of 35
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    Measuring Family Quality of Life for Children with Autism
    (2016-02) Settle, Theresa
    The purpose of this study was to investigate family quality of life for children with autism. In order to measure family quality of life, family leisure was used as a key indicator. The aims of the study were as follows: 1) to describe family leisure for children with autism, 2) to investigate which child characteristics were associated with family leisure for children with autism, 3) to compare family leisure for children with autism to family leisure for typically developing children.
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    Is Genocidal Behavior Learned? Assessing the Familial Ties of Genocide Perpetrators
    (2016-02) Gertz, Evelyn; Brehm, Hollie
    Samantha Power, United States ambassador to the United Nations, designated the 20th century “the age of genocide.” Since 1945, nearly 50 such events have occurred, causing more deaths than all internal and international wars combined. Foundational research on genocide perpetrators dates back to post-WWII and examines the motives of Nazi killers. These studies, with important exceptions, generally conclude that perpetrators are simply “ordinary men” responding to bureaucratic obedience structures. More recently, scholars have highlighted the role of interpersonal networks in shaping the dynamics of genocide. Fujii and McDoom find that local social ties, particularly those connected to kinship, explain patterns of participation in the 1994 genocide in Rwanda. Inspired by these studies, and utilizing data from Rwanda’s post-genocide Gacaca courts, I draw on criminological theories of socialization into deviance to investigate whether siblings’ behavior predicts violent versus non-violent genocidal crimes. Hierarchical generalized linear analyses indicate that exposure to siblings’ violence affects individual participation, suggesting that genocidal crime, like other types of crime, may be learned through interaction with intimate social ties.
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    Parental Exposure to Light at Night Prior to Conception Impairs Offspring Immune Function
    (2016-02) Cisse, Yasmine M.; Nelson, Randy J.
    Environmental light is the most potent signal for synchronizing the circadian system. Adoption of electrical lighting has occurred without consideration or understanding of the wide ranging physiological and psychological effects of light at night. Disruption of natural light/dark cycles by light at night (LAN) dampens endogenous biological rhythms to maintain optimal functioning of various organ systems. The immune system, especially T cell proliferation and NK-cell activity, displays circadian rhythms in function. Dim LAN (dLAN) exposure decreases plasma bactericidal capacity and impairs response to delayed type hypersensitivity (DTH), an antigen specific T-cell mediated immune response, in Siberian hamsters (Phodopus sungorus). Studies of the effects of circadian disruption on immune function have thus far focused on adults, but impaired maternal immune, endocrine, and metabolic function have downstream effects on offspring immune phenotype. The circadian system exerts an organizational role in all three of these systems and LAN impairs their function. Thus, we hypothesized that parental exposure to dLAN prior to mating impairs offspring immune function. Adult (8 week) male and female Siberian hamsters were exposed to either dark (DARK) or dimly lit nights (DIM) for 9 weeks, at which point they were paired, mated, and thereafter housed in dark nights. Pairings resulted in four groups: Dark/Dark (Male/Female), Dark/Dim, Dim/Dark, and Dim/Dim. Pups were gestated, born, and maintained thereafter under dark night conditions. At 8 weeks of age, cell-mediated immune function was assayed in offspring generated from these pairings by measuring swelling response induced by secondary exposure to a chemical immunogen, 2-4-dinitro-1-fluorobenzene. Four months later, humoral immunity was assessed by quantifying antibody production in response to keyhole limpet haemocyanin (KLH), a presumably novel antigen. Plasma bactericidal capacity was also assessed in offspring as a coarse assay of innate immunity. Male offspring of mothers exposed to DIM suppressed DTH mediated inflammation. In female offspring, both maternal and paternal exposure to DIM to decreased swelling response at 2 days and 3 days after challenge, respectively. Offspring of dams exposed to DIM produced more anti-KLH antibodies in response to challenge. No changes in plasma bactericidal capacity were observed. Overall, parental exposure to dLAN decreased offspring cell-mediated immunity and enhanced humoral immunity in a parent and offspring sex-specific manner. This suggests a shift towards Th2 enhancing humoral responses and away from Th1 cell-mediated responses. Altered immune responsiveness in offspring that have only experienced dLAN in the germline indicates that seemingly innocuous, but pervasive, nighttime lighting may have multi-generational effects on immune function.
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    'Dulce et Decorum Est': A Lost Generation of Roman Elites in the Hannibalic War
    (2016-02) Barber, Cary; Rosenstein, Nathan
    Between 218 and 216 BC, over half of the members of the Roman Senate perished while serving as officers and soldiers in the war against Hannibal of Carthage. That the Republic recovered from such a blow is astounding, for this loss amounted to the deaths of nearly every man of fighting age within the Roman political aristocracy. Yet, Rome did more than simply recover; by 200 BC, under a regime led by a clique of older nobles, the Republic had repulsed Hannibal from Italy and begun its imperial march to Spain, Greece, Africa, and beyond. Understanding both the crisis caused by the unprecedented decimation of Rome’s governing class and the nature of the Roman political and military response to this emergency is, I argue, indispensable to any account of Rome’s rise to Mediterranean hegemon in the decades following the Hannibalic War. Still, despite the decisive role which these events played in the social and political development of the Republic, there have been few meaningful modern attempts to reconstruct the particulars of Rome’s elite casualties in these years or to underline the significance of what was essentially a ‘Lost Generation’ of Roman leaders. My project aims to remedy this omission by combining a thorough analysis of our extant ancient sources with modern demographic modelling techniques. Using Hannibal’s early victories over the Senate and its commanders as a focal point for a larger examination of the internal age, rank, and power dynamics of the Roman ruling class, my paper will explore the disruptive effects of extraordinary elite war-time casualties on the political stability of the Republic and elucidate the general social and political consequences of aristocratic participation in warfare. What makes this undertaking important is that it aims both to expand on our received narrative for the still-murky era of Rome’s ascension and to correct a number of widely-accepted notions about the very nature of Roman political culture. The Roman Republic amounted to a highly competitive political arena in which Senatorial aristocrats contended annually with one another for election to a limited number of hierarchically-arranged offices, the most important of which offered supreme command over the Republic’s armies. Elites thus constantly vied for access to these offices in order to enhance their own and their family’s prestige, and could marshal vast resources in this pursuit. Custom, conservatism, and class solidarity, however, constrained this competition by tempering the ambitions of those in public life who, for future political gain, might attempt to undermine the larger meritocratic, semi-hereditary aristocracy of Senators by overreaching the customary limits of their office and challenging Senatorial oversight. This internal balance between individual ambition on the one hand, and collective checks on potential overstep on the other, allowed for not only Roman martial success, as commanders fought on behalf of the Republic for personal glory within limit, it also facilitated the transition of political control from one generation of elites to the next effectively and without significant strain. In the face of staggering losses, however, this system came undone, spelling serious consequences for the stability of the Republic with it. Indeed, my paper argues that the sudden disappearance of a full generation of younger and middle-aged Senators, their subsequent replacement with politically inexperienced and ineffectual aristocrats of lesser pedigrees, and a resulting shift in political power towards older survivors with decades of military experience, all help to account for the unusual and problematic dominance of a few individuals over the Senate’s collective authority. The years following the deaths of an entire cohort of political elites, I will argue, were characterized by the junta-like rule of older oligarchs who saved the Republic, but at the cost of suppressing competition from below for over a decade. Explaining the re-emergence of collective authority over the rule of individual dynasts is a complex undertaking, but as my project will show, a key element will be understanding the internal age and rank dynamics of the Senate and the role of inter-generational conflict in checking the power of any one group within the elite. By utilizing the explanatory potential of demographic modeling as a heuristic tool for enhancing our understanding of the political, social, and economic fallout of Hannibal’s dramatic victories over the Roman officer corps, we emerge with a more nuanced understanding of the Republic’s most important institution, the Senate, in the periods before, during, and after the struggle against Hannibal.
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    Five Phases Belief in Chu 楚: Sacrificing White Dogs to Save the Kingdom?
    (2016-02) Kong, Xueying; Chan, Marjorie K. M.
    This paper is a corpus-based study on excavated bamboo-slip inscriptions from Chu state around 700 BCE. -300 BCE. It examines in detail a particular sacrifice made of white dogs and the historical and religious contexts for this ritual. The results show that this occult practice was performed as part of the five-god ritual system of Chu state. In the ritual Chu people singled out white dogs as appropriate sacrifice because in their belief, the energy flow from white dogs were able to destroy Chu state. The whole idea was based on the Five Phases theory, which served as a logical foundation for many cultural practices and social custom in early China.
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    Traumatic Brain Injury Causes the Formation of Rod Microglia/Macrophages in the Cortex
    (2016-02) Witcher, Kristina; Godbout, Jonathan
    Background/purpose: Traumatic brain injury (TBI) is a leading cause of morbidity and mortality worldwide, with more than 6 million TBIs sustained annually in the United States alone. Human TBIs are heterogeneous; penetrating injuries result in focal necrosis and immune cell infiltration, while diffuse injuries cause more widespread pathology with minimal cell death. The absence of overt gross pathology causes diffuse TBI to seem milder; however, these patients experience myriad complications including brain swelling and seizures and increased risk for later development of depression and Alzheimer’s disease. Microglia, the innate immune cells of the brain, become acutely activated after TBI and release inflammatory cytokines, phagocytize debris, and take on altered morphologies. One such morphology is rod-shaped microglia, previously shown to align with neuronal structures. Rod microglia have been observed in human brains after chronic infection such as syphilis and typhus, in addition to animal models of stroke and Alzheimer’s disease. The role of rod microglia in TBI is currently unknown, thus we were interested in further characterization to determine if they contribute to neuropathology. Our objectives were (1) to determine if rod microglia align with blood vessels in the injured cortex, and (2) to identify whether their source of origin is from peripherally derived macrophages. Research method: A diffuse TBI was induced in mice using a midline fluid percussion injury. This models diffuse TBI in humans, evidenced by the absence of gross pathology, neuronal death, or long-term motor dysfunction. After 7d, brain tissue was fixed, sliced, and labeled for structural and activation markers including Ly6C, Iba1, and CD45. To assess peripheral trafficking, green fluorescent protein (GFP) chimeras were created. In these mice, all peripherally derived immune cells, including monocytes and macrophages, are GFP+ and readily identified by microscopy. Results: We show novel data indicating that Iba1+ rod-shaped myeloid cells form long trains perpendicular to the cortex in mice. Additionally, rod microglia aligned with Ly6C+ blood vessels, and these cells were thicker and in proximity to deramified highly activated microglia. Furthermore, both rod-shaped microglia and adjacent deramified microglia showed increased labeling of CD45, a marker associated with peripheral monocytes. Notably, thin rod microglia, in cortical areas with less microglial reactivity overall, did not associate with blood vessels. Using GFP chimeras, we found that TBI does result in trafficking of GFP+ monocytes to the brain. These peripheral myeloid cells differentiate into ramified macrophages and, after TBI, can take on a rod-shaped morphology; however, the vast majority of rod-shaped myeloid cells are resident microglia. Implications: We have confirmed that rod microglia are resident microglia, and not peripheral macrophages masquerading as microglia. Furthermore, our findings show that highly activated CD45+ rod-microglia align with blood vessels. In contrast, CD45- thin rod-microglia may align with neuronal structures. Our findings suggest that there may be two subsets of rod-microglia that may have different functions in the injured brain; the former may affect blood-brain barrier integrity while the latter may be involved in axonal repair and regeneration.
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    GDC-0853 inhibits both wild type and C481S BTK variants while preserving NK cell mediated ADCC
    (2016-02) Reiff, Sean; Woyach, Jennifer; Byrd, John
    Bruton's tyrosine kinase (BTK) has recently emerged as an attractive therapeutic target in hematologic malignancies. Ibrutinib, the first in class BTK inhibitor, improves survival and is well tolerated in patients. Here, we investigate a novel BTK inhibitor, GDC-0853, to evaluate its efficacy in chronic lymphocytic leukemia (CLL). GDC-0853 is unique among BTK inhibitors in that it utilizes a novel allosteric binding site, different from the C481 kinase domain to which ibrutinib irreversibly binds. Like ibrutinib, GDC-0853 blocks B cell receptor signaling, modestly reduces viability, prevents stromal and cytokine induced survival, and limits activation in CLL lymphocytes through the inhibition of BTK. We found that due to its novel site of action, GDC-0853 also inhibits C481S mutated BTK in an in vitro system. GDC-0853 is more selective for BTK than is ibrutinib which also irreversibly inhibits interleukin-2 inducible kinase (ITK), a Tec kinase responsible for T and NK cell activation. The selectivity of GDC-0853 preserves ITK function in T and NK cells. Unlike ibrutinib, upper-physiologic concentrations of GDC-0853 had no effect on T cell activation or NK cell antibody dependent cell mediated cytotoxicity (ADCC). Our results indicate that the GDC-0853 may be an effective therapy for use in CLL as monotherapy or in combination with anti-CD20 antibodies, especially among the emerging population of patients who are resistant to first generation BTK inhibitors.
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    ACD-crosslinked actin oligomers are potent toxins inhibiting formin-mediated actin polymerization
    (American Association for the Advancement of Science, 2016-02) Heisler, David B.; Kudryashov, Dmitri
    Bacterial toxins are the deadliest compounds on the planet; a single copy of a toxin is capable of compromising a host cell. Amplification of toxicity is typically achieved by enzymatically targeting signaling cascades or inhibiting vital host proteins/complexes present in relatively few copies. Due to its fundamental importance for a living cell, a major cytoskeletal protein, actin, is a common target of many toxins. However, due to the high abundance of actin in the cytosol it is not clear how actin-targeting toxins can achieve their high efficiency. One of such toxins produced by pathogenic strains of Vibrio cholerae, Vibrio vulnificus, and Aeromonas hydrophila, the actin crosslinking domain (ACD), catalyzes the formation of an amide bond between Lys-50 and Glu-270 of actin monomers, resulting in the formation of actin oligomers, which are unable to function properly. It was believed that ACD toxicity stems from a slow failure of the cytoskeleton due to the gradual accumulation of non-functional actin oligomers. However, this mechanism can be effective only assuming intracellular delivery of high concentrations of ACD toxin, because the in vitro rate of ACD activity applied to cellular conditions suggests that a single ACD molecule would require over 6 months to crosslink half of all cytoplasmic actin. On the contrary, we found that to implement its cellular toxicity, ACD is not required to crosslink all actin in the cell: the integrity of intestinal cell monolayers is compromised dramatically when only a small fraction (<6%) of the total cellular actin is crosslinked. This suggests that ACD-crosslinked actin oligomers even at low doses are toxic to cells. Since actin-binding domains of some actin-regulatory proteins are organized in tandems, these proteins potentially can bind to actin oligomers with affinities higher than those for a G-actin monomer, due to multiple binding sites accessible on a single oligomer molecule. This would render these actin-regulatory proteins non-functional. Formins are one family of such proteins governing the actin cytoskeleton dynamics important for numerous cellular processes. The main functional domains of formins, formin homology domains 1 (FH1) and 2 (FH2), cooperate in nucleation and elongation of actin filaments. Our data indicate that formins preferentially bound to the crosslinked actin oligomers with abnormally high affinity in cell culture. We found that actin polymerization controlled by formins was inhibited by sub-nanomolar concentrations of actin oligomers. To investigate the mechanism of formin inhibition exerted by the ACD-crosslinked actin oligomers, we preformed total internal fluorescence reflection microscopy (TIRFM) to monitor actin polymerization at the individual filament level. In the presence of profilin, the oligomers caused reversible blocks of elongation of formin-controlled, but not formin-free, filaments. The persistence of the blocks, as well as the fraction of blocked filaments was dependent upon oligomer concentration as well as the length of the FH1 domains, suggesting that both FH1 and FH2 domains of formin contribute to the inhibition in profilin-dependent and profilin-independent manners, respectively. Mathematical modeling of polymerization in bulk (pyrene actin assays) and on a single filament level (TIRFM) revealed that the oligomers potently inhibit both nucleation and elongation steps of actin filament assembly controlled by formins. Therefore, our findings implicate that ACD employs a novel toxicity mechanism by converting cytoplasmic actin into highly toxic oligomers that specifically target key steps of actin dynamics. This implies that toxins can not only exploit existing signaling pathways but also initiate a new toxicity cascade with de novo produced crosslinked actin species as “second messengers.” ACD creates toxic derivatives of actin with a disruptive “gain-of-function” mode of operation. These new actin species bind with high affinity to formins and adversely affect both their nucleation and elongation. We propose that the seemingly straightforward original assumption that ACD acts by the accumulation of bulk amounts of nonfunctional actin is inaccurate or at least incomplete. The toxin can be highly efficient at very low concentrations by acting on formins and, potentially, other actin regulatory proteins. This finding calls for the careful reevaluation of mechanisms used by other actin related toxins, both of protein and small-molecule natures.
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    Dynamics of Colonization of Cucurbits by the Bacterial Plant Pathogen Erwinia tracheiphila
    (The American Phytopathological Society, 2016-02) Vrisman, Claudio M.; Miller, Sally A.; Rajashekara, Gireesh
    Purpose of the study Bacterial wilt, caused by Erwinia tracheiphila, is one of the most destructive diseases of cucurbits (cucumbers, melons, squash, and pumpkins) in the Midwestern and Northeastern US. Younger plants are more susceptible than older ones, and can wilt within 6 days after infection. Wilting occurs due to multiplication of bacteria inside xylem tissue. Erwinia tracheiphila strains display a preference for colonizing the Cucumis (cucumber and melon) or Cucurbita (squash and pumpkin) host genus from which they were isolated. Although this disease has been studied since 1900, the dynamics of colonization remains unclear. As for most systemic bacterial diseases of plants, effective management products and disease resistant cultivars are not available. Plant pathogenic bacteria transformed with bioluminescence genes can be used to document colonization dynamics in plants non-destructively in real time. A sensitive camera captures the light emitted from transformed cells, allowing visualization of the pathogen inside living plants. We constructed a bioluminescent strain of E. tracheiphila to describe colonization dynamics in melon, cucumber, squash, and pumpkin plants. Research methods Cells of a strain of E. tracheiphila isolated from cucumber were transformed by electroporation of a plasmid carrying the bioluminescence genes. In vitro growth curves were evaluated and compared to the non-transformed wild type in rich medium. Pathogenicity of transformed strains was evaluated in cucumber and melon plants in two independent greenhouse experiments. One of the bioluminescent strains exhibiting no differences in growth or pathogenicity compared to the wild type was inoculated onto the second true leaf, stems, and roots of melon plants. Images were taken every 24 hours after inoculation. In a separate experiment, leaf-inoculated plants were photographed every 2 to 4 hours for 216 hours to generate a video of colonization. Cucumber, melon, squash, and pumpkin plants were inoculated with this bioluminescent strain on the second true leaf. Plants were monitored for wilting and bioluminescence for 35 days in three independent greenhouse experiments. Bacterial populations in the stem were quantified from each treatment 6 days post inoculation (DPI) and 35 DPI. Bacterial populations were quantified in squash and pumpkin roots 35 DPI. Findings Bioluminescent E. tracheiphila was observed in inoculated leaves and petioles beginning 1 DPI. The bacteria spread to roots via the stem by 2 DPI, and reached the plant extremities 4 DPI. Melon and cucumber plants wilted 6 DPI. To our knowledge, this is the first time that root colonization resulting from an above-ground inoculation has been demonstrated in this pathosystem. The dynamic process of upward and downward movement of the bioluminescent bacteria was clearly elucidated in the video. Populations of E. tracheiphila detected 6 DPI were four and seven orders of magnitude higher in the stem of preferred hosts, melon and cucumber, than in the non-preferred hosts of this strain, squash and pumpkin, respectively (p<0.001). Squash and pumpkin did not wilt, even 35 DPI. However, bioluminescent E. tracheiphila were detected in three out of nine squash roots 35 DPI, indicating the ability of the pathogen to move in the vascular system of non-preferred hosts without causing symptoms. Implications This study highlighted facts about E. tracheiphila that will be used to better elucidate the epidemiology of this understudied pathosystem. The potential for root colonization and overwintering of this pathogen in the root system of cucurbit crops has been ignored in the past. Roots could serve as inoculum source for E. tracheiphila and thus a target for management. Bioluminescent markers can be effective tools to characterize and improve the understanding of bacterial colonization, screen plant introductions, lines and cultivars, elucidate the dynamics of colonization inside alternative hosts, and, through colonization videos, assess and characterize the efficacy of antibiotics and bactericides in planta in real time.
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    Social Stress Causes Extramedullary Hematopoiesis in the Spleen
    (2016-02) McKim, Daniel; Sheridan, John
    Chronic psychological stress promotes hematopoietic production of proinflammatory innate myeloid cells, such as monocytes and neutrophils. Enhanced production of proinflammatory myeloid cells is tightly linked to negative health outcomes in both high stress populations. Circumstances with leukocyte demand (e.g., infection, cancer, blood loss) hematopoiesis may occur outside of the bone marrow, such as within the spleen. Mechanisms of enhanced myelopoiesis with stress are explored here in a mouse model of psychosocial stress. In vitro colony forming unit (CFU) assays were performed on bone marrow, blood, and spleen following six cycles of repeated social defeat (RSD) stress. RSD increased colony forming units in the blood and spleen but not the bone marrow. However, the phenotype of CFU in the bone marrow was shifted from erythropoietic to myelopoietic progenitors. Taken together these results show that RSD skewed bone marrow hematopoiesis towards myelopoiesis, and that RSD increased extramedullary hematopoiesis in the spleen. For the first time, this study demonstrates that social stress promotes extramedullary hematopoiesis as a novel mechanism of stress-induced myelopoiesis.
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    A theory for accelerated stress corrosion cracking in arc-welded aluminum alloys and mitigation by precision additive dressing
    (2016-02) Borchers, Tyler; Zhang, Wei
    Where stress corrosion cracking (SCC) of an un-welded high-strength aluminum alloy may not occur, gas-metal arc welding of the same alloy can induce SCC in an accelerated timeframe. This was found to originate from a metallurgical weld region called the fused-overlap zone (FOZ); the corrosion (pitting) reaction that occurs within the FOZ acts as the catalyst for accelerated SCC. Each of the necessary factors for SCC (i.e. corrosive environment, tensile stress, and susceptible material) is affected by arc-welding. In a saline solution, the corrosive environment becomes more acidic because of FOZ pitting; tensile stress intensity is increased by the geometric impact of FOZ and HAZ corrosion damage; the material’s susceptibility to SCC in the HAZ is increased because of the weld thermal cycle’s effect on strengthening precipitates. With respect to joint strength, practicality of production, and corrosion resistance, it was determined that precision additive dressing (PAD) is the most viable engineering solution to mitigate accelerated SCC of these welded high-strength aluminum alloys.
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    Word-of-Mouth: Positive and Negative Experiences with Hedonic and Utilitarian Products
    (2016-02) Teeny, Jacob; Petty, Richard
    Previous research has shown that a positive experience with a hedonic (vs. utilitarian) product leads to more word-of-mouth (WOM), whereas a negative experience with a utilitarian (vs. hedonic) product produces more WOM (Chitturi et al., 2008). Across three studies, we replicate this important finding and extend the mediational account for the effects. That is, with positive experiences, hedonic (vs. utilitarian) products produce greater attitude certainty which leads to heightened likelihood of intended WOM, while negative experiences with utilitarian (vs. hedonic) products produce less subjective ambivalence which leads to greater WOM intentions. Together, this research replicates prior findings and provides an explanation for its occurrence through a connection to the considerable research on attitude strength.
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    Contrasting Expressive Content in First and Second Musical Themes
    (2016-02) Warrenburg, Lindsay; Huron, David
    Since the 18th century, music theorists have noted the tendency for art-music works to contain themes exhibiting contrasting expressive content. In music exhibiting two main themes, the first theme is commonly characterized as stronger or more energetic, whereas the second theme tends to be gentler or more lyrical (Marx, 1845; Koch, 1793). In the first study, an examination of 1063 musical works was conducted using the Humdrum Toolkit, where first and second themes were compared on six structural features: modality, average interval size, rhythmic smoothness (nPVI), pace, dynamics, and articulation. Consistent with the higher energy hypothesis, first themes tend to be faster, louder, more detached, and use larger interval sizes than do second themes. The second study, a perceptual task, tested whether people are sensitive to these changes in musical structure. Musicians (n = 44) were tested on their ability to discriminate between pairs of musical themes in 22 piano works. Participants completed two tasks, one based on the musical score and one based on sound recordings. The task was presented in an alternative force choice format, where people were asked to identify which of the two themes comes first in the music. Additionally, the type of information available in the musical excerpts was manipulated so that in some trials, participants did not have access to dynamic and articulative information. The results indicate that musicians are able to differentiate between first and second themes in both the score-based (p < 0.001) and recording-based tasks (p < 0.01), and that people perform better when information about dynamics and articulation is included (p < 0.01). The results are consistent with the claim that musicians can perceive structural and expressive differences between first and second themes, even outside of the original musical context.
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    Generating Illegality and Precarity through Forced Resettlement in Peri-urban Delhi in India
    (2016-02) Bose, Debangana; Ettlinger, Nancy
    The United Nations (UN) entrusted the UN Habitat in 2006 with the responsibility to assist member states to monitor and gradually attain the “cities without slum” target, also known as Target 11 of the Millennium Development Goals (Millennium Development Report 2015). In large cities in India, migrants frequently squat on public land in inner city where they have easy access to basic amenities such as sanitation, drinking water, and health care as well as job opportunities. Target 11 prescribes its member states to provide tenure rights to the poor squatting in public land in large cities. However, instead of ensuring land-tenure rights city governments in India have displaced the poor from the inner city to the periphery through forced resettlement programs. Following economic reforms in 1991, large cities in India opened up to the global investment market and adopted decentralized governance forming localized public-private partnerships called Urban Local Bodies (ULBs). Since the 1990s city governments along with the ULBs and transnational firms (TNCs) – what I call the city government-ULB-TNC complex or Growth coalition– have undertaken projects to restructure the social and spatial composition of the city to create a slum-free city attracting foreign investment (Ghertner 2011, Kundu 2009). In Delhi alone, the city government has evicted around 420,000 slum households in the inner city since the 1990s, constituting 15 percent of the city’s population (Sheikh et al. 2014). Approximately 50 percent of the displaced poor have been resettled in the planned resettlement colonies located in the periphery. The resettlement policy permits the resettled to live on—but not own, rent or sell—plots, and prohibits commercial activities in the resettlement colonies (Sheikh & Banda 2014). However, approximately 40 percent of the resettled sold their plots through illegal land markets controlled by land mafias who sell the plots to other displaced poor lacking entitlement to resettlement, thereby creating new forms of illegal settlements within the planned resettlement colonies. I ask why the resettled are restricted from owing, selling or renting their plots and why do they sell their plots through illegal land markets? How and why illegal land markets are produced and what are their implications in terms of the expansion of the city and the lived experiences of the local residents? My research strategies draw from qualitative methods informed by critical ethnography, feminist studies as well as post-structural theory. Countering the conventional science-inspired triangulation approach, which involves the use of multiple methods to verify the Truth, I follow Ellington’s ‘crystallization’ as field approach to recognize the existence of multiple realities viewed from different lenses (Ellingson 2009; Elwood 2010). Drawing from semi-structured interviews and focus groups with local residents during my field research in summer 2015 at Savda Ghevra, the largest resettlement colony in Delhi, I explain how lack of tenure rights of resettlement plots and prohibition of commercial activities in these plots compel the unemployed poor to take up illegal avenues to earn livelihood. I also conducted semi-structured interviews and focus groups with multiple actors such as local leaders, land mafias, NGO workers, local lawyers assisting residents in resolving property conflicts and actors of the Growth coalition to understand their perception about as well as lived experiences of illegality. Interviews with officials at the Growth coalition also reveals that they are aware that residents of the resettled colonies routinely sell their land illegally, and moreover, both the residents and the Growth coalition recognize that illegal activities will be suppressed in future through the eviction of the new illegal settlers by the government to grab land for urban expansion. Archival research shows that ‘legitimation,’ the act of making something acceptable to the public, is an important strategy for land grabs in urban planning in India. For example, throughout the 1990s the middle class, the ULBs and the TNCs have identified squatter settlers in the inner city as encroachers, ‘nuisance,’ and agents of environmental degradation to legitimize their plea for slum eviction to the judiciary issuing court orders for eviction (Baviskar 2003 ;Ghertner 2011,2012). Moving beyond the common conception that resettlement territorializes the poor, my research shows that resettlement also is a process creating new forms of illegal settlements, legitimizing further rounds of eviction by the Growth coalition to acquire more land for development projects. The threat as well as experience of multiple rounds of displacement legitimized through the production of illegality thereby constructs precarity, a persistent condition of uncertainty having deleterious consequences among the urban poor (Ettlinger 2016). I draw from Foucault’s conceptualization of ‘popular illegality’—the tacit and tolerated non-enforcement of laws—which recognizes that illegality is essential for the normal functioning of the society and that it becomes an organized form of governance (Foucault 1977). Illegal activities do not necessarily indicate the absence of order or norms; rather, the widespread nature of illegal practices constitutes ‘normal’ life. For example, Foucault explains that the modern penal system was not designed to eliminate crime but to differentiate ‘rights’ from ‘wrongs’ and assign punishment to particular crimes (Foucault 1977). In the resettlement colonies in Delhi informal institutions of land markets and illegal commercial activities sustain a locally organized system of livelihood for the poor, setting the government free of welfare-related responsibilities such as providing land tenure or jobs. My research contributes to a broader ongoing debate on the suitability of Foucauldian framework of analysis in the international context as well as to the literature on the interaction of a regime of poverty and regimes of planning.
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    Lincoln's Divided Legion: Emancipation and the Political Culture of the Army of the Potomac, 1861-1865
    (2016-02) Fry, Zachery; Grimsley, Mark
    The Army of the Potomac was the most politically unstable and problematic of all the Union field armies in the Civil War. This project examines the partisan divide within the army by exploring the extent to which such issues as emancipation and conscription caused heated disagreement from the top of the command chain down to the enlisted men. Soldiers often carried out these debates in the public eye by contributing to newspaper columns, which in turn influenced the northern public sphere. The dissertation also tracks the process by which Republicans in the army were able to monopolize the concept of wartime loyalty by 1863 to mean a disavowal of many in the Democrat Party. When former General George B. McClellan emerged as the Democrat standard bearer in 1864, soldiers turned on their old commander and voted instead for Lincoln and the war platform.
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    Rocking the Boat: The Effects of Status Change on Helping Behaviors within Hierarchical Groups
    (2016-02) Doyle, Sarah; Lount, Robert
    When examining how people behave within hierarchies, researchers commonly take a snapshot of the current hierarchy, overlooking the status shifting that may have just occurred. The current research takes a more dynamic perspective to status within groups, examining how the experience of individual status change, both status loss and status gain (as compared to not changing in status), influences helping behaviors within hierarchical groups. Namely, I argue there are asymmetries in how helping behaviors are influenced by status change. That is, individuals who lose status will help less than individuals whose status does not change; however, individuals who gain status will not necessarily help commensurately more. I have conducted two studies which together test the asymmetry effect of status change on helping, provide evidence for why this asymmetry occurs (i.e., changes in other orientation: the tendency for people to focus on collective qualities or joint inputs contributing to the group’s success), and identify a critical boundary condition for the effect (i.e., source of change: whether status change is framed as being due to a personal change or due to a relative others’ change).
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    Motivation of Electroceutical Bandages for Treatment of Chronically Infected Wounds
    (2016-02) Bennett, Molly; Prakash, Shaurya
    In the United States, 6.5 million patients are affected by chronic wounds, sometimes complicated by infection. If the bacteria form a biofilm at the wound site, treatment of the infection becomes significantly more difficult. Biofilm bacteria are 500 to 5,000 times more resistant to antibiotic medications than the non-biofilm bacteria. Previous studies have shown that electric current enhances the activity of various antibiotics against biofilm-forming bacterial strains such as Pseudomonas aeruginosa and Staphylococcus epidermidis. This behavior has been referred to as the electro-bactericidal effect. A large parametric investigation with various substrates, conductive patterns, and designs has led to a novel electroceutical bandage comprised of a silver-based ink on silk fabric, connected to a 6 V DC battery source and switch circuit for easy operation. Currently, characterizing the electroceutical bandage includes in vitro tests using the bacterial strain Pseudomonas aeruginosa to test the efficacy of biofilm inhibition. The results have shown that our dressing successfully and repeatedly prevents the bacteria from forming a biofilm, as well as excludes bacteria from the anode of the bandage. It is noteworthy that use of an isolated electrode system i.e., electric field applied to the bacteria without direct flow of current through the bacterial layers, did not yield inhibition of the biofilm formation. Therefore, mechanistically, one may expect oxidation reactions at the anode to be important. This hypothesis is the subject of further on-going experiments. Further in vitro tests studying the effects of the bandage on already established biofilms have been initiated as well. It is important to study both scenarios because this electroceutical bandage should prevent infection from developing at the wound site, as well as help treat existing infections. Severe biofilm infection can lead to amputation to prevent spread of infection. If more reliable and successful means of treating biofilm infections can be implemented, complications of chronic wounds will be reduced. We have shown that engineered bandages with direct electric current flow between the wound-bandage interface inhibit bacterial growth at and around the anode. Due to this result, the conductive pattern design has been optimized to maximize this effect by increasing the surface area of the anode with respect to the available space on an average dressing of 5 cm x 5 cm. Currently, our measurements show a power density of 0.75 mW/cm2, well below the FDA limit of 0.25 W/cm2 for thermal burns therefore implying likely safe use of the dressing. We hypothesize that the direct electric current is disrupting quorum sensing, or communication between the bacteria, effectively isolating them from each other due to oxidative stress at the anode. We believe this isolation prevents bacteria from forming a biofilm. The future experiments will focus on developing a more comprehensive understanding of the mechanisms behind biofilm inhibition in presence of low-magnitude direct currents.
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    Genetic Ablation of Smoothened in Tumor-Associated Fibroblasts Promotes Pancreatic Tumorigenesis
    (2016-02) Pitarresi, Jason R.; Ostrowski, Michael C.
    Pancreatic cancer remains an overwhelmingly fatal disease with less than 5% of patients surviving beyond 5 years, largely due to our lack of understanding of the complexity of the disease. Many recent reports have begun to highlight the potential role that stromal cells—fibroblasts in particular—may have on pancreatic tumor cell biology and this report provides data that supports the theory of tumor-stroma co-evolution in pancreatic cancer. Here we use a novel mouse model to show that Smoothened (Smo) in the tumor-associated stroma suppresses pancreatic tumor initiation and development. We observed an increase in tumorigenesis events such as acinar-to-ductal metaplasia (ADM) and pancreatic intraepithelial neoplasia (PanIN) lesions when Smo is conditionally deleted in pancreatic cancer associated fibroblasts (CAFs). To determine how Smo in fibroblasts is able to effect tumor progression, we harvested pancreatic CAFs from Smo-deleted and Smo-intact tumor bearing mice and performed microarray gene expression analysis. We found that Smo deleted CAFs had significantly altered the tumor suppressor PTEN, resulting in misregulated Phosphoinositide 3-kinase (PI3K) oncogenic pathway signaling. Thus, Smo ablation in pancreatic fibroblasts enhanced pancreatic tumor initiation primarily through loss of PTEN in fibroblasts. This report shows that deleting a gene in pancreatic fibroblasts causes a change in tumor-stroma co-evolution and that Smo is able to act as a novel tumor suppressor in cancer associated fibroblasts to promote pancreatic carcinogenesis.
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    Visualizing Sight Experience
    (2016-02) Baczeski, Lillianna Marie; Hamilton, Ann
    Eye-tracking technology is used by scientists to explore and make measurable claims to advance knowledge in pursuit of the question: How do humans see? Though I am not a scientist, my investigations originate from the same question. In my current work, I approach this question with the tools of a scientist, but with the capacity of an artist.
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    Cosmic-ray muon spallation backgrounds for MeV astrophysical neutrino signals in Super-Kamiokande
    (Physical Review C, 2016-02) Li, Shirley; Beacom, John
    When muons travel through matter, their energy losses lead to nuclear breakup ("spallation") processes. The delayed decays of unstable daughter nuclei produced by cosmic-ray muons are important backgrounds for low-energy astrophysical neutrino experiments, e.g., those seeking to detect solar neutrino or diffuse supernova neutrino background (DSNB) signals. Even though Super-Kamiokande has strong general cuts to reduce these spallation-induced backgrounds, the remaining rate before additional cuts for specific signals is much larger than the signal rates for kinetic energies of about 6–18 MeV. Surprisingly, there is no published calculation of the production and properties of these backgrounds in water, though there are such studies for scintillator. Using the simulation code fluka and theoretical insights, we detail how muons lose energy in water, produce secondary particles, how and where these secondaries produce isotopes, and the properties of the backgrounds from their decays. We reproduce Super-Kamiokande measurements of the total background to within a factor of 2, which is good given that the isotope yields vary by orders of magnitude and that some details of the experiment are unknown to us at this level. Our results break aggregate data into component isotopes, reveal their separate production mechanisms, and preserve correlations between them. We outline how to implement more effective background rejection techniques using this information. Reducing backgrounds in solar and DSNB studies by even a factor of a few could help lead to important new discoveries.