1.A.1 A Malaria Type Effector in the Soybean Cyst Nematode Modulates the Plant Immune System

s 2015 Symposium on Undergraduate Research & Creative Expression PRESENTATION SESSION I 1.A.1 A Malaria Type Effector in the Soybean Cyst Nematode Modulates the Plant Immune System Danielle Andrews Cyst nematodes (CNs) are sedentary endoparasitic round worms that infect the roots of economically important plants such as soybean, potato and sugar beet. CNs secrete proteins (effectors) into root tissues and cells to promote parasitism. Sequence analyses of one CN effector determined that it has marginal, but significant similarity to an effector found only in the Malaria parasites (Plasmodium spp.), the Circumsporozoite Protein (CSP). Furthermore, the CN effector and Plasmodium CSPs share four protein domains that are essential for CSP function inside animal cells. Numerous evidences indicate that Plasmodium CSPs suppress the immune systems of their animal hosts by multiple, diverse strategies. As plants have immune systems, with significant overlaps with the animal innate immune system, we performed assays to test whether the CN effector suppresses plant immunity. Remarkably, multiple lines of evidence indicate that the CN effector strongly suppresses both of the major routes of the plant immune system. We are currently testing whether a CSP from the monkey Malaria species, P. fieldi, which the CN effector is most similar to, also suppresses plant immunity. We hypothesize that the CN effector and CSPs have converged on similar sequences to execute similar functions in their plant and animal hosts, respectively. 1.A.2 The Effects of Cover Crop Termination on Subsequent Corn Seedling Growth Abigail Peterson Cover crops are grown to protect and improve soil during fallow periods between crops. The benefits of cover crops include preventing soil erosion, increasing nutrient retention, and suppressing weeds. A challenge associated with cereal rye cover crops is that sometimes there is a decrease in corn yield the following year. Cereal rye is one of the main cover crops planted in Iowa, and like corn is also a grass species. Because of this relationship both grasses may be attacked by the same plant pathogens. I hypothesized that if a winter rye cover crop was terminated with glyphosate a few days before planting corn, then there would be an increase in corn root seedling infection caused by higher levels of pathogens passed on from the dying rye plants. I found that terminating rye cover crops three days before planting corn resulted in an increase in mesocotyl infection and shorter radicles than terminating fourteen days before planting. To evaluate the source of root infection, DNA extractions were conducted to detect specific fungal pathogens in the Pythium and Fusarium genera infecting the corn radical, both three days and fourteen days after termination, with and without using the herbicide glyphosate for termination. 1.A.3 Oxygen Demand of Red Flour Beetles in Sorghum Christian Miller Sorghum is the third most internationally traded cereal grain in the world and is Nigeria’s highest produced cereal grain. Full return storage is pivotal to maintaining edible feed in this region. Hermetic storage, which is a non-chemical storage method that utilizes the capability of oxygen seals for possible aerobic asphyxiation of pest, has been evaluated for the control of the red flour beetle (Tribolium castaneum), which causes large storage losses. Using hermetically sealed containers and a fixed ratio of beetles to sorghum mass at different temperatures (22°C and 34°C) and grain moisture (8% and 16%), the oxygen requirement of the red flour beetle was determined. Time to 100% beetle mortality in hermetic storage, as a function of infestation level, storage volume, temperature and grain moisture content, can be estimated by using these oxygen requirements results. These estimates can be utilized to design effective hermetic storage systems for sorghum. 1.B.1 Increasing Escherichia coli Membrane Robustness to Long-chain Fatty Acids Will Black "Product generation through genetically modified microorganisms has enabled scientists to produce hydrocarbons, antibodies, and proteins of their choosing. However, the inhibitory nature of these products reduces production rates and final titer of products. Genetically modifying microorganisms to withstand these products so they can continue to produce product at higher concentrations is just one way to bring these bioproducts to a competitive economic scale. Here, we investigate the deletion of two proteins, protein X and protein Y, associated with fatty acids in Escherichia coli MG1655. These proteins allow for the buildup up fatty acids in the cell, which degrade the cell membrane and inhibit growth. The knockout of protein X did not yield an increase final free fatty acid titer. However, the knockout of protein Y significantly decreased the final titer achieved, the opposite trend as expected. The double knockout of protein X and protein Y resulted in the same decrease in fatty acid titer as the protein Y knockout, but the double knockout stain exhibited drastically different growth rates. The double knockout enabled growth rates to rise, and the final titer was reached over twice as fast as the other three strains. The deviation from expected results could help understanding additional functions of these proteins. 1.B.2 Using Biomaterials to Reduce Fibrous Encapsulation of Biomedical Implants Catherine Le Denmat Fibrous encapsulation, commonly referred to as scar formation, can cause failure in many biomedical implants, such as in the artificial pancreas for type I diabetes treatment. Scar tissue prevents wastes and nutrients from being able to be exchanged in the implant, ultimately rendering the treatment painful or ineffective. For example, one potential therapeutic for type I diabetes involves using a polymer to protect insulin-producing cells. This artificial pancreas provides diabetics with their much needed insulin on-demand. If scar tissue forms around this artificial pancreas, the device loses the ability to deliver insulin and becomes useless. Our goal is to reduce the fibrous encapsulation of implants using biomaterials and improve the understanding of how cells involved in scar formation respond to biomaterials. We show that our materials can reduce fibrous capsule formation by inhibiting certain physiological pathways. This research will not only improve the success of the artificial pancreas, but other biomaterials. 1.B.3 T4 Phage Drying on Paper Christoper Lim Recent technological advances have enabled scientists to develop different types of products to detect water contamination by bacteria. These products are accurate, but they are expensive and conducting a field test is still a challenge for them. Our research focuses on providing a method to overcome these challenges by using bacteriophage as our biological indicator for contamination. The specific bacteria and phage that we use are Escherichia coli K-12 and T4 respectively. Our first research objective is to determine whether our method is viable or not. We first test whether T4 phages still show activity when bound to a filter paper. Then various stabilizer solutions are introduced to the T4 phages to determine whether their addition can aid T4 phages in maintaining their activity over time after binding to filter paper. Different time-dependent drying methods are then introduced to study how drying time will affect the T4 phage activity. Lastly, the T4-bound filter paper will be stored to determine the shelf life of T4 phages. Our qualitative research then can be used as a framework for a quantitative research in studying how phages concentration on paper changes over time. 1.B.4 Mesophorous Block Copolymer Membrane Sittinon Nuethong "Block-copolymer research has long been a center of attention among engineers and scientists seeking solutions to combine two thermodynamically incompatible polymers with hybrid properties. This research focuses on creating triblock copolymers from polystyrene, polyisoprene, and polydimethylsiloxane using an anionic polymerization technique to synthesize then etch of one of the polymer’s block to form a mesophorous membrane. A series of experiments was conducted to form block-copolymers of different molecular weights, which were then tested for their flexibility and permeability. The goal is to develop suitable block-copolymer membranes that can be tailored to the specific needs to support “microbial factory” that are currently facing the incompatible polymer separations challenges. 1.C.1 Values and Attitude Change Ban Joo Ang The amount of time it takes for an attitude to be expressed (i.e., accessibility) is one of the most basic structural properties of an attitude and an important factor to consider in attitude strength (e.g., attitude extremity). Despite its importance, relatively little work has examined the role of accessibility in an inter-attitudinal context, particularly as it relates to the strength of related attitudes in the network. The present research examined the role of accessibility of an individual’s political ideology (i.e., beliefs about how liberal or conservative one is) may polarize an attitude associated with their political ideology (i.e., gun control laws). The study utilized a repeated expression paradigm to manipulate accessibility of one’s ideology, such that participants expressed their political ideology either once (the single expression condition) or eight times (the repeated expression condition). Participants then reported their attitudes toward gun control laws prior and after writing their thoughts about their attitude. As expected, participants in the repeated expression condition a) had more polarized attitudes toward gun control laws and b) reported that their thoughts reflected their political ideology more than in the single expression condition. Implications for the role of accessibility in inter-attitudinal strength are discussed. 1.C.2 The 50 Shades of Social Rejection: The Role of Rejection-Sensitivity in Everyday Exclusion Experiences Alison Miller Being rejected is rarely a pleasant experience. However, the reactions people have to being excluded are more consequential than the rejection itself. Critically, individuals differ in how they perceive and evaluate rejection circumstances. In fact, rejection sensitivity refers to an individual's disposition to "anxiously expect, readily perceive, and overreact to rejection" (Downey & Feldman, 1996). Rejection sensitive individuals have a heightened vulnerability to experiencing rejection and responding in a maladaptive way (including instances when there is no intended rejection). To what extent the rejection experiences these individuals have differ from those of others in terms of type of rejection (outright rejection vs. passive exclusion), source (friend vs. romantic partner), or specific emotional reactions (e.g., anger) still remains largely unknown. To this end, the present study will examine the nature of rejection experiences reported by highly rejection-sensitive individuals, identify distinctive qualities of these experiences, and test whether they are more likely to involve angry reactions. The findings will illuminate everyday experiences of rejection and will reveal the unique nature of social experiences of rejection-sensitive individuals. 1.C.3 In the Line of Fire: Post-Traumatic Stress Effects on Officers Involved in Shootings Logan Godar Individuals who face violent and critical situations often times experience acute stress disorder and posttraumatic stress symptoms. In this study, we will be illustrating the correlation between critical shooting incidents and the stress symptoms and disorders that follow. In addition to the acute post-traumatic stress symptoms measured, I documenting physical experiences each officer had during the critical incident. Mapping individual experiences during the incident, directly after, and an extended period afterwards, is to show how the recovery process happens and what factors lead to a better and quicker recovery. This study surveyed officers involved in critical shooting incidents within their career. Respondents answered both quantitative, and qualitative questions which measured physical distortions (time, visual, and auditory) and cognitive alterations during and after the incident. In addition, respondents were asked to give their opinions on what would assist and improve the emotional recovery of the officer(s) involved. The collected information shows that emotional debriefing, time off, and departmental support are correlated to the amount of psychological stress an officer may experience post-shooting. These results help illustrate how to efficiently handle a critical incident and how to help the subjects receive optimal recovery. 1.C.4 Suspect Suggestibility During Police Interrogations Brooke Kindelsperger Previous research on police interrogations have operated under the premise that as an interrogation persists, a suspect’s resistance to interrogative influence steadily declines. However, addressing the issue from the perspective of a stress and coping framework suggests that the threat of police interrogation may cause a suspect’s resistance to initially spike, similar to the flight or fight response, and only afterwards might a suspect’s resistance begin to decline. This research tested the first half of this prediction by examining whether the threat of police interrogation increases a suspect’s resistance to interrogative influence. Participants (N = 364) were made to be either guilty or innocent of cheating on a laboratory task and either accused or not accused of academic misconduct by the experimenter. The accusation manipulation was intended to vary the threat of the situation. Participants’ resistance to interrogative influence was assessed with a measure of suggestibility. The results supported the hypothesis by showing that participants who were accused of cheating exhibited less suggestibility than participants who were not accused. In other words, participants for whom the situation was more threatening showed greater resistance to interrogative influence than did participants for whom the situation was less threatening. 1.D.1 Metals Binding by Methanobactin from Methylosinus trichosporium OB3b and Methylocystis strain SB2 Nathalie Fuentes Methanobactin is a class of copper-binding peptides produced and secreted by some methanotrophs as the extracellular component of a copper acquisition system. In addition to copper, methanobactin has the ability to bind a variety of metals. It was shown, that extracellular compound of methanotrophs might lead to an increase in the mobility of some heavy metals. Since both, methanotrophic bacteria and heavy metals, are present in hazardous waste sites, it is necessary to study their role in the environment. This research focuses on the metal binding properties of two types of methanobactin: Methylosinus trichosporium OB3b (mb-OB3b) and Methylocystis strain SB2 (mb-SB2). We examined the ability of SB2-mb to bind the lanthanoids Cerium III chloride heptahydrate (Ce3+), Neodymium III nitrate hexahydrate (Nd3+) and Praseodymium III nitrate hexahydrate (Pr3+). Our results indicated that mbOB3b might be binding Ce3+, Pr3+ and Nd3+ whereas mb-SB2 shows little or no binding for these metals. However, further studies are needed to confirm our findings. 1.D.2 Reduction of Cell Wall Methylation Affects Plant Growth and Stress Resistance Lauran Chambers Pectin Methylesterase is an enzyme present in plants and some microbial organisms and plays an important role in plant growth and stress resistance. The Zabotina lab created a transgenic Arabidopsis plant expressing a fungal pectin methylesterase (AnPME) within the cell wall. We are elucidating the effect of AnPME on the plant’s resistance to abiotic stresses. Overall, AnPME plants exhibit stunted growth and dwarfed features in comparison with wild type. From previous experiments, AnPME plants are more resistant to salt stresses, but under osmotic and reactive oxygen stresses demonstrated a similar phenotype to the wild-type plants. Future testing of PEG stress (imitation of drought conditions) will be conducted. Ongoing experiments to characterize the effect of the pectin methylesterase in-depth include a western blot to confirm presence of enzyme in the apoplast in active form, an enzymatic activity assay, and cell wall compositional analysis. TAIL-PCR will be used to confirm the position of the AnPME within the Arabidopsis genome. Our research will give us a better understanding of cell wall integrity and advantages and disadvantages to utilizing the AnPME gene. 1.E.1 Atmospheres: Explication and Excess Matthew Darmour-Paul As the world becomes increasingly quantifiable and as innovative technologies allow for novel measurements of new phenomena, it is the ‘givens’ of everyday life, and the responsibilities a new attentiveness may harbor, that are under the so-called ‘attack’ of modernity. Architecture is not immune to this phenomenon, particularly in the trending topics of study such as ‘climate design’ and ‘atmospheric construction’. These are cited both as a response to an impending climate change, and as a technical means to design large commercial projects. As architects find ways to incorporate new representational technologies into the discipline, new ‘materials’ such as heat or the density of vapors are being made visible, and are therefore subject to manipulation. It is crucial that the architectural community is critical of these new awarenesses, before they are implemented at large scales. By analyzing the work of two architectural atmospherists one begins to identify a series of explications and the questionable contradictions they present. It can be argued that it is both the fundamentally vague conceptual basis of atmospheres and their simultaneous revealing of latent environmental potential that engenders an ethos of wasteful energy practices, and a distancing of authorship, and therefore control, in atmospheric design. 1.E.2 Rethinking the Way We Live: A Case for Passive House Retrofitting Jackie Katcher In order to reduce our energy consumption in buildings, it is best to begin with the individual and therefore, housing. The residential sector contributes 54% of all energy consumption related to buildings, and it is also a personal environment for each of us to live and grow. Because of the deep connection we have with our homes, it is important that these houses are not only energy efficient and affordable, but also comfortable and enjoyable places for us to live in. Weatherizing and updating appliances and mechanical equipment in existing houses isn’t enough to significantly reduce energy consumption and lower operating costs. The passive house standard, which was developed in Germany, is currently the most rigorous energy standard created and aims to achieve not only a reduction of a building’s ecological footprint, but also to create houses that are more comfortable and enjoyable places to live. In this study, I will discuss how the passive house standard is applied to existing homes and the importance of implementing this way of thinking into our daily lives. My research includes a building performance analysis of an existing conventional home in Ames and a design proposal of how one might retrofit an existing building to the passive house standard. 1.E.3 The Interlock House Environmental Control and Alert System Kelsey Fleenor One of the problems in architectural research involving sensors is detecting errors within raw data and separating these errors from the reliable and relevant data. This research on the Interlock House aims to develop an alert system to notify when the house is operating below efficiency and for identifying abnormal data caused by sensor errors/failures. Additionally, the system would assist in controlling environmental settings. There are three parameters for operating this alert system. The first parameter, used to signify if a sensor is malfunctioning, includes the range for each sensor’s capabilities based off technical specifications. The second parameter, derived from historical data, signifies data that does not have historical precedence (ex. record breaking temperatures). The third parameter, depending on what the specific sensor is measuring, focuses on either the range of human comfort or equipment specifications, using the maximum and minimum again, to control environmental settings and identify when a mechanical component is malfunctioning. Together, the historical data and equipment standards aid in identifying when the house is operating below efficiency. The ideal results of this research would improve the energy efficiency of the Interlock House and thereby provide a model for improving the efficiency of other buildings.