Undergraduate Research Posters 2016

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  Life Behind Glass: Bioreactor studies on the Salt-water adaptation of Scenedesmus dimorphus

  Joshua Hartranft, Alex Fedai, and Sahar Ataya

  Algae has considerable promise as source for liquid biofuel because of high productivity and because algae farms do not compete with food crops for arable land. Freshwater algae is preferred over saltwater algae because of the higher lipid content in the former. Unfortunately, freshwater algae “farms” would require a vast amount of fresh water, and given the scarcity of fresh water, this is not a viable long-term solution. Therefore, the adaption of a fresh-water species of algae to a salt-water environment is a potential solution. In this study, it was shown that the growth rate of the freshwater algae S. dimorphus increased over 3-fold in a salt-supplemented growth medium (16.6% of the salinity of pure ocean water) compared to that in standard growth media. Additional research will be needed to determine the level of salinity that can be tolerated by this species.

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  Design and Development of a Microfluidic Platform to Induce Mechanical Stimuli on Growing Axons

  Edward Jira and Erin Tesny

  In cases of injury and degenerative diseases, stresses can be placed on individual nerve cells in the human body that greatly, and often permanently, impact the function of the human nervous system. In order to treat these it is imperative to better understand the effects these stresses can have on the development and function of individual neurons. Because of the logistical difficulties of studying cells in-vitro, it has become increasingly popular to study neuronal cells in vivo using microfluidic devices. Current studies focus mainly on the impact of chemical signals on neurons. The focus of this study however, is to develop a versatile system for testing a variety of mechanical stimuli and its effect on axonal outgrowth and signaling in neurons. In this study a microfluidic device was designed and produced in which neurons could be cultured. The device design encourages unidirectional axon outgrowth in the cells so that once the cells are grown, stresses applied to the device itself will impact each cell in a similar manner. With the mold created, a high number of identical device can produced and cultured in parallel to study different mechanical stimuli such as tension and compressive forces placed on the axons.

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  Scalable Assembly of Nanoparticles onto Templated Substrates

  John Juchnowski

  Anisotropic nanoparticles, such as carbon nanotubes and noble metal nanorods, have excellent electrical, mechanical, and thermal properties. This work examined techniques for the nanopatterning of silicon substrates for the subsequent deposition of anisotropic nanoparticles in order to exploit their properties in macroscopic applications. Argon-ion-sputter induced rippling of Si (100) as well as a microparticle mask were examined as methods for templating a silicon substrate. For the ion-sputter

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  Phosphorus concentrations in the Cuyahoga River watershed linked to anthropogenic inputs

  Christopher Kasden

  Twenty-four water samples were taken from twelve sites throughout the Cuyahoga watershed from upstream to downstream within two separate occasions. Twelve samples were taken on May 25th, 2016 with no prior precipitation and the conditions were calm, and twelve samples were taken on July14, 2016 when high precipitation had occurred and water conditions were much more diverse. Using the Automated Discrete Analyzer, the concentrations of phosphorus could be analyzed and differentiated between Total Phosphorus and Soluble Reactive Phosphorus. In comparison to the Environmental Protection Agency whose target concentrations for rivers is .05ppm, in both cases of the experiment the hypothesis has been conclusive with maximum concentrations of .14ppm on May 25th and .20ppm in July14. Although phosphorus levels were lower in May than July, the results were conclusive and consistent with an increase of phosphorus from source points to downstream. SRP is more of an interest because of the properties in which allows the utilization by Cyanobacteria and other types of algae. Excessive growth can lead to issues such as increased dead zones, raising levels of biological oxygen demand and diminishing water quality overall.

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  Ground Reaction Force Measurement with a Piezoelectric Insole

  Mohamad Khattab

  The objectives of this research project are to design and build an instrumented shoe to measure the vertical ground reaction force (GRF) associated with a person walking or running. Sensor outputs are calibrated to actual GRF with an artificial neural network. Currently, GRF measurements require special equipment such as force plates or scientific treadmills. A force plate measures GRF over a limited area. A shoe insole fitted with sensors was identified as a good solution that allows free-range walking over arbitrary surfaces. Piezoelectric film sensors were chosen due to their low cost, flexibility and for being self-powered. Eight sensors were bonded to a conventional insole and wires attached. A data acquisition interface was prepared using a dSPACE MicroLabBox system, which contained digital filters for noise removal. Training and validation data were collected using a force-sensing treadmill available at the Parker-Hannifin Human Motion and Control Lab at CSU. A 3-layer feedforward network was successfully trained to approximate the training data. A separate data set was used to validate the trained network. A normalized root mean square error associated with training was 1.01, while the error in validation was 2.78.

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  Identification of Factors that Mediate Strand Exchange During Early Meiosis at Low Double Strand Break Levels

  Isaac Kuragayla and Rima Sandhu

  Genetic recombination is essential in order to create diversity amongst all of the genetic information. Crossovers also contribute to segregation of homologous chromosomes to opposite spindle poles during the first meiotic division. Meiotic strand exchange in Saccharomyces cerevisiae, budding yeast, aims to diversify genetic information in the resulting gametes which in budding yeast are called spores. While Dmc1 and Rad51 are two proteins that are known to play a role in double strand break (DSB) repair, the exact function of Rad51 is still unclear. It is known that Rad51 is responsible for strand exchange in mitosis, but it is still present in meiosis, even when Dmc1's catalytic strand exchange activity alone is sufficient for repairing DSBs into crossovers. In this project, we carried out a budding yeast strain construction to identify the function of three proteins in strand exchange during early meiosis, when nucleus-wide DSB levels are low. So called Spo11 hypomorphs were used to lower DSB levels during meiosis and thus mimic the conditions of early meiosis. Spo11 hypomorphs express a version of the DSB forming topoisomerase homolog Spo11 that exhibits reduced activity. Three strains (A, B and C) which express a catalytically inactive version of the A gene, or a presumed activator of the A protein, were mated with a Spo11 hypomorph, and haploid spores were derived from diploid precursor cells. Double and triple mutants were identified based on antibiotic marker genes associated with the respective mutations. Southern blot analysis was used to confirm the presence of the relevant mutations in genomic DNA extracted from spore offspring. We hypothesize that during early meiosis at low DSBs, a distinct subset of proteins, including genes A and B, mediate strand exchange during homologous recombination, with protein A functioning as a potential activator of protein B.

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  The Use of iPad Pros as an Assistive Device in Occupational Therapy

  Osorio Lana

  RESEARCH QUESTION: How can IPADS be used as an assistive devices for children and adults with disabilities? A literature review was conducted using the keywords, in order to find articles about using iPads as a therapeutic device. As a result it was concluded that iPads due to its versatility and popularity has made great progress as a therapeutic tool. Apps recommended as having a therapeutic purpose were also purchased and installed. The iPads will be used as a learning device amongst the Health Science Programs at Cleveland State University. KEYWORDS: iPad, assistive technology, occupational therapy, tablet, allied health, assistive therapeutic devices.

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  Design and Characterization of Protein-Based Bioink

  Ryan Martin and James Deyling

  Elastin-like polypeptide (ELP) based, temperature responsive triblocks are an attractive alternative to current cell encapsulation hydrogels (bioinks) used in bioprinting, due to their natural physiological properties and their potential for higher cell viability. Many cell encapsulating hydrogels in current use, require UV light to initiate crosslinking which can be damaging to the encapsulated cells. Other materials irreversibly gel with a change in temperature potentially clogging the bioprinting instruments. ELP based hydrogels utilize temperature dependent gelation, but gel reversibly. Elastin is a natural material in human tissue which many protein scaffolds are made of. We are studying an ELP triblock consisting of a long hydrophilic center ELP segment with a short, temperature responsive ELP segment at each end. When a solution of these ELP triblocks is brought to a transition temperature, the end segments become hydrophobic and phase separate. This results in a crosslinked hydrogel network of hydrophobic ELP nodes connected by hydrophilic ELP segments. The ELP hydrogel's properties are dependent on concentration, temperature, pH and salt concentration of the solution. We have characterized the gelation behavior through temperature dependent and time dependent complex modulus profiles of the ELP hydrogel measured using a rheometer with cone and plate geometry. This study is an important step in designing a temperature responsive solution that gels between room and physiological temperature.

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  African Clawed Toads’ Responses to Visual and Lateral Line Stimuli

  Marko Milosavljevic and Kevin Goth

  The African Clawed Toad, Xenopus laevis, is an aquatic species commonly found throughout Sub-Saharan Africa. Adults use vision to sense movements and lateral line to sense vibrations in the water. Here, we analyze the effectiveness of the toads' vision and lateral line systems individually and in combination. This study will help us understand how Xenopus utilizes sensory information to capture prey. We tested which sensory system elicits greater responses, how stimulus angle and distance affect the probability of a response, and if the toads respond equally to visual and lateral line stimuli. We found that a combination of both visual and lateral line stimuli elicited the greatest response rate (55%). Compared to this, lateral line stimuli alone elicited almost equal response rates (42%). In contrast, visual stimuli alone were less effective (12%). In addition, toads were more likely to respond to rostral stimuli than to caudal stimuli. When a response was elicited, latencies did not differ according to stimulus type.

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  Dialects Accents and Intelligence: A Study on Dialectal Perceptions

  Taylor Moore

  Speech language pathologists are given the tools to help clients with a wide range of pathologies. Issues relating to speech, hearing, swallowing, etc can all benefit from a Speech language pathologist's insight. One area that can be difficult is dialect. People across America speak with many different dialects and speech language pathologists are taught to recognize these differences but not correct them. Dialect showcases culture but does not define intelligence. Dialects like African American Venacular English are rule governed systems of communication (Carter, 2012). The research done on AAVE is seemingly endless (Baugh, 1983; Pearson,2013; Robinson,2011; Carter 2010; Bronstein,1970......) and many of them compare AAVE to Standard American English(SAE). Very few studies, however, look at other dialects and even fewer compare these dialects to something other than SAE. This study compares African American Vernacular English, Standard American English, and Arabic Accented(AAccented) English in the areas of perceived likability and intelligence. 30 adults listened to three different voice samples. Each sample featured a speaker of one of the tested dialects/accents. They then completed a survey rating each speaker's likeability and intelligence. I hypothesized three things: (1) The speaker of AAVE will be perceived as less intelligent and less likeable than other dialectal speakers, (2) The speakers of SAE will be perceived as more likable and more intelligent than the dialectal speakers, and (3 )The speaker of AAccented speech will be perceived as more intelligent and more likeable than AAV, but less intelligent and likeable than speakers of SAE. These findings may be useful in changing the way SLP's think about dialects and accents.

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  Effect of Calorie Restriction on Circadian Rhythms of Glycolytic Enzymes in Mice

  Enas A. Muhammad, Artem Astafev, and Kuldeep Makwana

  Multicellular and unicellular organisms have all proven to exhibit circadian rhythms which persist over approximately 24 hours. This internal time keeping system is responsible for regulating the body's biological functions. It has been known that calorie restriction effects circadian rhythms by causing a response in clock gene expression. These clock genes react to food intake and become either upregulated or downregulated accordingly. With glycolysis being a biological pathway that occurs in most organisms, measuring glycolytic gene expression in the liver tissue of young male mice becomes of interest. More specifically, hexokinase, PFK-1, and pyruvate kinase are the enzymes of interest. By analyzing the expression of key regulatory glycolytic genes in the liver tissue of mice, the importance of how diet effects circadian rhythm will be revealed. Results have shown that calorie restriction has some effect on circadian rhythms of glycolytic gene expression. We propose that if calorie restriction effects the circadian rhythms in the expression of glycolytic genes, then a down regulation in the profiles of ad libitum mice will be seen and an upregulation of calorie restricted mice's genes will be shown.

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  Elimination of Acoustical Noise for STM Examination of Pentacene Crystallization on Si (001)

  William Myers and Mark Bowling

  Organic electronics are used in traditional solar cells and also in flexible electronics. Unfortunately, the conductivities of organic semiconductors are significantly lower than their inorganic counterparts. This project examines crystallization by directed selfassembly of the organic molecules via a surface reconstruction as a method to increase conductivity. The crystallization is characterized by Scanning Tunneling Microscopy (STM). In order to achieve optimal STM images, this work examined: (1) noise isolation, (2) etching sharp STM tips and (3) achieving reconstructed Si surface. The STM is housed in a glovebox to keep the surface reconstructions and organic molecules from degrading. However, acoustical noise of the glovebox circulation pump makes achieving atomic resolution impossible. Introducing a foam-lined acoustical shell around the microscope significantly reduced acoustic noise and atomic resolution is achieved. We also determined optimal PtIr tip etching procedures, demonstrating that an alternating current of 40 V in a 1M CaCl2 solution results in a tip with an ~ 13μm radius of curvature, comparable to other PtIr tips found in literature. Finally, we demonstrated a Si(001) surface with 20nm terrace widths and two atomic height steps achieved by cleaving inside the N2 environment.

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  The Digitalization of and Research with Real Estate Archival Records: A Longitudinal Study of Changes in Land Use on Miles Avenue

  Rasheedah Najieb and Amelia Caldwell

  with beam energies between 1 and 5 keV, and ion beam fluxes between 1700 and 5000 □ A/cm2. Rippled structures were not observed under these conditions. As an alternative, we used a single layer of microspheres which had been arranged into a close-packed structure as a template. This surface will then be irradiated at normal incidence with argon ions. By doing so, a network of channels is expected to be formed in-between the microspheres. Future work will examine the influence of beam flux on the formation of rippled structures, as well as exploring the effect of variations in particle size and concentration on the formation of large monolayer template areas.

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  Identifying Patterns of Stress Through Biological Markers

  Kristyn Oravec

  technique, the angle of incidence of the ion beam was 67° from the surface normal,

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  The identification of anti-cancer molecular targets of COX-2 inhibitor Nimesulide

  Yuridia Olivera Ortiz and Nethrie D. Idippily

  Non-steroidal anti inflammatory drugs which were primarily used for the treatment inflammation and pain have also shown anti-cancer activity in many studies. The mechanism of action of NSAIDs in cancer may involve cyclooxygenase (COX) dependent or independent pathways. According to studies, COX-2 is overexpressed in several cancers such as prostate, breast, nonsmall-cell lung, colon, and pancreas. Nimesulide is an NSAID with COX-2 inhibitory activity and investigations show that it could induce apoptosis in cancer. Previously, a library of compounds was synthesized using Nimesulide as a lead compound. However, they displayed different molecular targets: tubulin and heat shock protein 27 (HSP27). Since Nimesulide does not interfere with any of these proteins, the targets of it in cancer remain unclear. Therefore, it is necessary to identify the original anti-cancer targets of Nimesulide in order to understand the structure activity relationship that lead to target switching in the Nimesulide derivatives. For this purpose, a six carbon linker and biotin conjugated Nimesulide probe was designed and synthesized. A human prostate cancer cell line, LnCap, was used to perform protein pull-down assay in order to analyze the proteins that bind to the Nimesulide probe. This study provides insight into the structural interactions that are important for the anti-cancer activity which can be used to synthesize more potent analogs with the original target of Nimesulide.

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  Sequential and dynamic RNA:RNA base-pairing interactions between U6atac and U12 snRNAs predicted to form Helix 1a and Helix 1b

  Maitri Patel and Jagjit Singh

  In eukaryotes, pre-mRNA splicing is important step for gene expression. Splicing is a two-step process which is carried out by a multi-megadalton molecular weight ribonucleoprotein (RNP) machinery called spliceosome. Spliceosome converts pre- mRNA to mRNA by removing non-coding sequence (introns) and splice together coding sequence (exons). Mammalian pre-mRNA are spliced by two different class of spliceosomes which are known as U2- and U12- dependent spliceosomes. U12 dependent spliceosome is composed of five small nuclear RNAs (snRNA). As compared to U2-dependent spliceosome, there is very less known about the catalytic process of U12-dependent splicing. U6atac and U12 snRNA are central to U12- dependent splicing. Therefore, to understand importance of U6atac and U12 snRNA interaction during splicing we have created a series of 2nd site nucleotide mutations in both U6atac and U12 snRNA to test for their functionality in in vivo splicing assays. Our work will help to better understand the catalytic process of minor class spliceosome and involvement of these snRNA in mammalian gene expression and genetic disorders.

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  How Big is a Cloud: A Statistical Analysis of Cloud Size Distributions Derived from Large Eddy Simulations

  Dorothy Pharis and Nicholas Barron

  To accurately represent cumulous clouds in climate and weather models, it is important to understand how large clouds, in certain cloud fields, are. These fields can be described by a cloud size distribution (CSD), the number of clouds of a certain defined size. This study utilized data from a Large Eddy Simulation (LES), a high resolution numerical model describing the atmosphere, to explore what defines the cloud size distribution. First, we have developed a toolkit to illustrate the cloud size distribution by using the slope and deriving an estimate for the scale break. Second, we performed a statistical analysis of cloud size distributions for several cases and measurement methods. Based on this analysis, we found that cloud size distributions do not compare well from case to case; but are comparable, regardless of time, within cases. Large eddy simulations of smaller domain sizes result in cloud fields that underestimate the number of clouds. Lastly, analyzing the cloud size distribution methods showed that, although similar, not all measurement methods obtain identical results. In particular, CSDs from linear transects through the cloud layer (“fly-through”) deviate significantly from other methods.

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  Which Clouds are Important: Variation of Cloud Size Distribution Functions in Large Eddy Simulations

  Dorothy Pharis and Nicholas Barron

  Accurately measuring and modeling clouds is an important factor in improving weather and climate prediction. One way of measuring the most important cloud size in a cloud field is a cloud size distribution (CSD) function, or the number of clouds per cloud size within the field. The information from a cloud size distribution can then be used to determine which cloud sizes contribute the most to cloud cover. This research focuses on creating and comparing cloud size distributions for a variety of cumulus cloud fields generated by Large Eddy Simulations (LES), a high resolution computer model. Our work found that the majority of the cloud fields followed the same functional form of a power law with a scale break, or change in exponent at larger cloud sizes. However, considerable variation was found in the value of the exponents and scale break location between different cloud fields, while some fields had no scale break at all. This is in contrast with previous studies that showed the scale break was the only changing element. We suggest that this discrepancy is caused by small domain sizes in previous studies limiting large cloud formation.

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  Synthesis and Characterization of Lectin Mimetics (Neo-Lectins)

  Czharena Kay Rama and Joshua Whited

  The cell surface expresses a variety of carbohydrates such as glycoproteins, proteoglycans and glycolipids. They play critical roles in pathological and physiological processes, including cell signaling, immune responses, pathogen-host interactions, tumor metastasis, and other cellular events. Due to its function and uses in cell communication, it is a curious subject of observation for scientific research. The molecular mechanism of carbohydrate recognition is still undetermined, and lectins, sugar binding proteins, are used to analyze the particular structures expressed on the cell surface. Lectins are normally found in plants and animals, and the isolation process of lectins is laborious, toxic, immunogenic and because of this it is considered a major drawback. Therefore, the exploration of lectin mimetics provide an alternative to natural lectins with multiple advantages. Bovine serum albumin conjugated with boronic acid (BA) was used in this experiment to mimic the function of lectins. Boronic acids (BA) have unique properties for carbohydrates, they form cyclic esters with diols of sugars in aqueous solution. BA conjugates are used as artificial carbohydrates receptors, drug delivery agents, and can be used to visualize the carbohydrates on the cell surface. Lectin mimetics, alternatively known as neo-lectins, preferably interact with terminal sialic acid residues at physiological pH. The research goal is to utilize BSA-BA as synthetic lectins for glycomic applications and immunotherapy.

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  Voices of Incarcerated Mothers

  Markisha Robinson, Lukas Hamlescher, and Jasmine Conkle

  This project was two-pronged—it explored the impact of video journaling on functional outcomes for incarcerated mothers, and it created documentary content for understanding methods for changing knowledge and attitudes toward incarcerated mothers in the general population. The project team developed and executed a threeweek original, pilot video reflective journaling program for incarcerated mothers at the Ohio Northeast Reintegration Center (NERC). Using the Motivation Enhancement and Therapy perspective, emergent themes for successful re-entry of the women into their families were discovered. And, the team collected a wide array of documentary assets—focus groups and individual interviews of incarcerated and released mothers, the video journaling, person-on-the-street interviews, and B-roll footage--for inclusion in stimulus materials for experiments to test the power of different documentary forms for “changing hearts and minds” with regard to incarcerated mothers.

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  Effects of Flanking Bigrams on Decision Performance in Selective and Divided Attention Tasks

  Nicole Russo and Jamie Rodman

  In previous research, lexical decision performance for word targets flanked by pairs of letters was better when flankers consisted of letters in the target (e.g., BI BIRD RD; RD BIRD BI; IB BIRD DR; DR BIRD IB) than of non-target letters (e.g., CE BIRD NT). Also, performance was better when flankers contained letters ordered as in the target (e.g., BI BIRD RD; RD BIRD BI) than switched (e.g., IB BIRD DR; DR BIRD IB), but flanker order relative to the target did not affect performance. That flankers affect lexical decision performance indicates that participants do not attend selectively to the target. We sought to replicate and extend these findings and also examined performance in a comparison experiment that required attention to the flankers: Participants indicated whether the flanker letters were the same as (e.g., BI BIRD RD; NE BUNE BU) or different from (e.g., CE BIRD NT; CA BUNE RF) those in the target. We found no systematic effects of flankers on “word” responses in the lexical decision experiment. In the comparison experiment, for “same” responses, we found performance differences among flanker conditions. Further, although lexicality was irrelevant, we found directionally different effects of lexicality on “same” and “different” responses.

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  Expression of Recombinant Proteins in Bacteria for Antibody Production

  John Sabljic, Anton Denisyuk, Hallie Schmolz, and Olivera Prica

  The protozoan parasite Trypanosoma brucei causes fatal African trypanosomiasis in humans and nagana in cattle. Transmitted by the tsetse fly, T. brucei proliferates in the bloodstream of its mammalian host and evades the host's immune response by regularly switching its major surface antigen, VSG, which forms a thick coat on its cell membrane. VSGs are exclusively expressed from sub-telomeric regions of the T. brucei genome in a strictly monoallelic fashion. Telomeres, DNA-protein complexes located at chromosome ends, help maintain chromosome stability and integrity. We have also found that telomere proteins are important for regulating VSG expression and switching. We are currently studying functions of telomere proteins in antigenic variation. Antibodies against several proteins including a novel telomere protein, Tb1710, the catalytic subunit of telomerase, TbTERT, and a DNA recombination protein involved in DNA damage repair, TbRAD51, are important reagents enabling us to detect these molecules using molecular approaches. We therefore aim to express recombinant proteins in bacteria and raise customized antibodies that specifically recognize these proteins. We have made all expression constructs for these recombinant proteins and are currently purifying these proteins.

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  Wrist-Mounted Feedback System: Monitoring Force and Torque in Six Degrees of Freedom

  Christopher Schroeck

  This project developed a wrist-mountable, six Degrees of Freedom (DoF) feedback system that monitors force and torque. This system is designed to be used by nontechnical operators to correct movements of a paralyzed arm under the control of a functional electrical stimulation (FES) neuroprosthesis. The resulting corrections are recorded and processed by additional programs so as to improve the accuracy of future movements controlled by the FES system. The feedback system was tested on a robotic arm that is programmed to simulate a paralyzed human's arm. These tests checked the sensor for accuracy, reliability, durability, ease of use, and stability. After production and testing, the feedback system was found to be durable enough to repeatedly withstand the forces of moving the robotically simulated paralyzed arm. The system was considered easy preform corrections with by testers after having minimal to no prior instruction and can readily record forces and torques input during the correction process, accurate within ±1N.

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  Defining an Enriched Environment for Pre-Ambulation Training using a Multi-Directional, Over-Ground Harness System for Young Children with Down Syndrome

  Lauren Schuck and Lisa Haecker

  This theoretical literature review aims to define the components of an enriched environment (EE) while using a multi-directional, over-ground harness system (MOH), for pre-ambulatory children with Down syndrome (DS). While using an EE has not been clearly defined within humans, children with DS may benefit from this combination of interventions to optimize developmental outcomes. Of the 15 articles critiqued, 6 were found to be most relevant to help define an EE with specific activities when using a MOH for pre-ambulation training. As a part of defining an EE within a MOH, activities will be suggested that stimulate the four components of an EE: social, sensory, cognitive and motor skill acquisition. This description will include specific parameters such as the motor action to be elicited, the position of child within the harness, how the environmental should be set up, specifics regarding task implementation and examples of toys to utilize to enhance the emergence of motor skills, including independent walking. Although ensuring the presence of all components of an EE can be challenging, the optimization of outcomes from using an MOH in an EE in young children with DS may allow for improved function and quality of life long-term.

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  High-Throughput Assessment of Developmental Stages of NSCs via Promoter-Reporter Assay System Using Recombinant Lentiviruses

  Emily Serbinowski, Pranav Joshi, Kyeong Nam Yu, and Yana Sichkar

  Many drugs and chemicals currently available have not been fully evaluated for their toxic effects on the developing brain. Expensive and low-throughput in vivo studies are still being used to evaluate developmental neurotoxicity (DNT). Thus, there is a need to develop an in vitro assay system which is economically feasible and high- throughput. Among various cellular models used for in vitro assay, human neural stem cells (NSCs) are highly desired due to their ability to self-renew and differentiate into neurons, astrocytes and oligodendrocytes. In vitro assessment of developmental stages (proliferation and differentiation) of human NSC is highly important to predict the in vivo effect of various chemicals on developing brain. However, conventional in vitro assay uses immunofluorescence staining to monitor changes in cell morphology and neural cell-specific biomarkers which can either be inaccurate or cumbersome. Therefore, we have developed an in vitro promoter-reporter assay system to monitor the proliferation and differentiation of NSCs using recombinant lentiviruses. Four NSC-specific biomarkers can be monitored by infecting NSCs with recombinant lentiviruses such as synapsin1 for neuron differentiation, glial fibrillary acidic protein (GFAP) for astrocyte differentiation, myelin basic protein (MBP) for oligodendrocyte differentiation, and SOX2 for self-renewal.