IBE-2019: 2019 INSTITUTE OF BIOLOGICAL ENGINEERING ANNUAL CONFERENCE
PROGRAM FOR SATURDAY, APRIL 6TH
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09:00-11:00 Session 10A: Advances in Biological Engineering Education Practices
09:00
David Jones (University of Nebraska, United States)
Framework for the Professional Formation of Biological Engineers

ABSTRACT. Professional formation is an important and recognized responsibility of biological engineers and continues to be an important educational objective. A variety of programs and strategies are deployed intending to develop biological engineers with professional skills and acumen leading to contributing and productive careers. This paper discusses professional formation from the perspective of individual development. Development is focused on the dimensions of academic, professional, and personal formation; definition of goals, discovery of weaknesses, and strength identification.

09:20
Ferris Pfeiffer (University of Missouri, United States)
Heather Hunt (University of Missouri, United States)
Johannes Strobel (University of Missouri, United States)
Suzanne Burgoyne (University of Missouri, United States)
Teaching Creativity to Bioengineers—and Everybody Else

ABSTRACT. Creative thinking is a critical 21st-century skill - creativity is directly related to and a requirement for innovation - that is typically neither taught nor encouraged in K16 classrooms. In an effort to investigate integrating creativity instruction into STEM education at the undergraduate level, our group has been teaching theatre-based creativity lessons to bioengineering senior design students for four years, with surprising results. In our curriculum, students are allowed to self-select into groups based upon capstone design projects. All students receive lecture based design content for 75 minutes one day a week as well as 75 minutes of studio instruction developed by a theatre professor (Burgoyne). The studio instruction was developed to facilitate the design content as well as help students experience and enhance their creative thinking skills. For instance, a short lecture comparing convergent and divergent thinking is immediately followed by a theatre exercise in which the class, divided into two groups, put divergent thinking into action by quickly inventing forty ways to cross a room. Theatre games help the students develop a safe, supportive environment in which students can begin to venture outside their comfort zones, because unless they are willing to risk trying something new - and making mistakes - students can’t be creative. A validated survey was utilized to evaluate pre and post-semester student self-efficacy. The results of this work indicate there is significant potential to improve engineering students’ creative self-efficacy through the implementation of a “curriculum of creativity”.

09:40
Timothy Kassis (Massachusetts Institute of Technology, United States)
Rebekah Costello (Massachusetts Institute of Technology, United States)
Ronit Langer (Massachusetts Institute of Technology, United States)
Dorothy Szymkiewicz (Massachusetts Institute of Technology, United States)
Ning 'Alexa' Guan (Massachusetts Institute of Technology, United States)
Julie Vaughn (Massachusetts Institute of Technology, United States)
Adil Yusuf (Massachusetts Institute of Technology, United States)
Amitava 'Babi' Mitra (Massachusetts Institute of Technology, United States)
Eric Alm (Massachusetts Institute of Technology, United States)
Linda Griffith (Massachusetts Institute of Technology, United States)
MIT's Living Machines: An Engineering Education Transformation (NEET) Thread

ABSTRACT. The biotechnology and medical device industries are witnessing fundamental changes in how products are developed. With increasing complexity comes an increasing level of interdisciplinarity. The majority of R&D, manufacturing, testing, and clinical implementations are carried out by interdisciplinary teams ranging from chemists to electrical engineers to computer scientists. Thus for undergraduate science and engineering majors, narrow training in a specialized discipline is no longer adequate for the modern day workforce. To address this, we recently launched a new School of Engineering sponsored undergraduate education initiative that emphasizes project-based interdisciplinary research. Interested students, from any technical discipline at MIT, join the program staring the beginning of their sophomore year and remain until they graduate. During their time in NEET - Living Machines, they work on a variety of real-world research projects under the theme of host-microbiome interactions. All work is conducted in the context of interdisciplinary teams. Students go through a structured set of classes, undergraduate research opportunities, internships, team projects, career development experiences, company site visits, mentorship programs, technical and interpersonal skill development and get ample opportunities to present their work both at MIT and to the broader scientific community. In addition, they are presented with multiple opportunities to pursue leadership roles within the program. By the end of the three years, students graduate with a degree in their respective major and a certificate in Living Machines having gained valuable real-world skills such as team-work, understanding cross-disciplinary terminology, critical thinking, and problem-solving.

10:00
A.J. Walters (Utah State University, United States)
Ron Sims (Utah State University, United States)
Charles Miller (Utah State University, United States)
Development of Synthetic Biology Kits for STEM Education

ABSTRACT. Implementation of advanced biological curriculum in STEM education is inhibited by limited funding, poor hands-on laboratory protocols, and lack of infrastructure. These same barriers afflict researchers in laboratories worldwide, particularly in developing countries. This project helps make scientific discovery possible for everyone. The current workhorse of synthetic biology research is Escherichia coli. It requires expensive equipment to successfully engineer. Our project replaces E. coli with Bacillus subtilis. B. subtilis is naturally competent, allowing it to be engineered without specialized equipment. It is also able to grow at room temperature, reducing the need for incubators. B. subtilis is non-pathogenic and is Generally Regarded As Safe (GRAS), unlike the opportunistic pathogen E. coli with Biosafety Level 1 (BSL-1) status. We are developing an open source kit for improving hands-on wet laboratories in STEM education and biological research. In this kit, the user will genetically engineer B. subtilis to produce a red fluorescent protein. This protein can then be produced at a larger scale to produce something tangible. Examples include dog bones for tensile strength measurements in a university engineering course or hand strung fibers in a high school biology lab. This kit will be “hackable”, meaning that the user will be encouraged to use the biological tools provided to conduct their own experiments. These kits have the potential to impact the K-12 and collegiate education system and public opinion through community outreach. In short, the development of these kits could have dramatic impact on the next generation of synthetic biology research.

10:20
Ferris Pfeiffer (University of Missouri, United States)
Heather Hunt (University of Missouri, United States)
Johannes Strobel (University of Missouri, United States)
Suzanne Burgoyne (University of Missouri, United States)
Implementing a Pedagogy of Creativity into Summer Programming in an NSF REU Site

ABSTRACT. Innovation and discovery are intended byproducts of research. However, without the right foundation, it is difficult for researchers to achieve these desired outcomes, regardless of effort. In universities today, this foundation is frequently laid through research experiences for undergraduate students, as well as more intensive summer programs, like the NSF Research Experiences for Undergraduates (REU) program. While many factors and experiences go into developing undergraduate students today into the successful researchers of tomorrow, one critical factor that these experiences seek to promote is students’ ability to innovate, which requires students to think not only critically, but also creatively. In the summer of 2018, our group implemented evidence-based creativity activities into our REU Site’s programming, intending to train the REU students to become creative thinkers and innovators in all aspects of their professional lives. Students worked with a research project mentor over the 8 week REU experience, as well as attended weekly creativity instruction studio sessions developed from our work in bioengineering capstone design. This was our first effort to apply the pedagogy of creativity to engineering students outside of a classroom-based senior design project framework. Students were assessed pre- and post-semester to evaluate changes in creative thinking. It was discovered that students who participated in the studio session demonstrated a substantial increase in their creative thinking abilities. However, the engineering students did not exceed national averages for creative thinking, which indicates that, although we saw substantial improvement, we still have room for improvement in teaching engineers to think creatively.

10:40
Maxine Jonas (MIT, United States)
Anthony Kulesa (MIT, United States)
Julie Sutton (MIT, United States)
Steven Wasserman (MIT, United States)
Paul Blainey (MIT, United States)
Douglas Lauffenburger (MIT, United States)
A BioMakerSpace at MIT enables hands-on, student-directed exploration of biological engineering

ABSTRACT. A BioMakerSpace at MIT enables hands-on, student-directed exploration of biological engineering Tony Kulesa, Maxine Jonas, Julie Sutton, Steven Wasserman, Paul Blainey, Doug Lauffenburger

To salute the energy and value of the maker movement in education and answer the students’ demand for laboratory benches to perform self-directed independent research in the life sciences, we have launched a biomakerspace for the MIT community. Opening the Biological Engineering Department teaching labs off-hours to the biomakers has helped us over the last couple of years develop key partnerships and processes around environmental health and safety, intellectual property, mentorship, training, and accounting. Students have brought sophisticated projects to the biomakerspace, including platelet-aided drug delivery, bacteriophage infectivity, jugular vein pressure ultrasound measurement, or alkaline battery chemistry. While 2500 square feet are being renovated to host MIT’s permanent biomakerspace, we are strengthening a vivacious community intent on invention, experimentation, and connection with the larger innovation ecosystem in the Boston area. The biomakerspace supports both education and outreach in biological and biochemical engineering. In addition to welcoming student teams with well-defined research ideas, we are developing activities with diverse purposes: education (practical implementation of a capstone class proposal; hands-on introductory workshops to synthetic biology, microfluidics, etc), entrepreneurship (to address problems enunciated by a consortium of local biotech and pharmaceutical companies), professional development, networking, and outreach. In a new space for safe and ethical exploration of the life sciences, the biomakerspace experience supports and complements the education and research goals of MIT faculty and students.

09:00-11:00 Session 10B: Bioenvironmental Engineering & Monitoring
09:00
Parker Dulin (Iowa State University, United States)
Carmen Gomes (Iowa State University, United States)
Kaoru Ikuma (Iowa State University, United States)
Use of stem-loop DNA probes in biosensors targeting Legionella pneumophila in drinking water

ABSTRACT. Over recent years, major events like the Flint Water Crisis have forced the public to consider the quality of their potable water, especially with respect to the presence of pathogens. Legionella pneumophila belongs to a group of pathogenic strains of emerging interest known as opportunistic premise plumbing pathogens. These microorganisms are resistant to chlorination, exhibit thermal tolerance, and can survive in oligotrophic conditions. Therefore, even with current drinking water treatment procedures, these pervasive pathogens can survive and multiply in water distribution and premise plumbing systems. In fact, reported cases of Legionnaires’ disease have increased significantly in recent years. As such, the need for sensitive methods with faster turnaround time for detecting L. pneumophila is rising. Due to the high selectivity of DNA hybridization, DNA-based biosensors can serve as applicable tools for in situ pathogen monitoring and detection. In this research, we hypothesized that the use of DNA probes targeting L. pneumophila with a stem-loop secondary structure would improve hybridization sensitivity compared to more traditional linear DNA probes. Hybridization of the probes to the target DNA sequence was measured at different DNA concentrations and surface coverages of the nanoparticle. Preliminary results suggest that the stem-loop structure of the probes results in improved hybridization compared to linear probes. Experiments are currently underway to confirm these results in both free probes and nanoparticle-immobilized probes. This research proves that through small manipulation of the probes, DNA-based biosensors have the potential of becoming more sensitive point-of-use devices for water quality monitoring and public health protection.

09:20
Abbas Kadhem (university of missouri-columbia, United States)
Shuting Xiang (university of missouri-columbia, United States)
Maria Fidalgo (university of missouri-columbia, United States)
Photonic Molecularly Imprinted Polymer Film for the Detection of Testosterone in Aqueous Samples
SPEAKER: Abbas Kadhem

ABSTRACT. A novel photonic sensor was fabricated based on molecularly imprinted polymers (MIP) for the detection of testosterone. MIPs porous films are obtained using colloidal crystals as templates for the pore morphology. Monodisperse silica nanoparticles (NPs) were synthesized via the modified Stöber method and then self-assembled on glass surfaces by the vertical deposition method. Particle size was determined by Dynamic Light Scattering (DLS) and Scanning electron microscopy (SEM). Spheres with an average diameter 330 nm and relative standard deviation less than 5% were obtained. The MIP is synthesized with acrylic acid as monomers, EGDMA as a cross-linker and testosterone as imprinting template molecules. Evaluation of the MIPs was done by incubation of the films in testosterone solutions at different concentration for 24h. The residual concentration in the solution was determined by High-Performance Liquid Chromatography (HPLC) to calculate the specific and non-specific adsorption capacities. The imprinted film demonstrates higher selectivity and sensitivity compared with the non-imprinted film (NIP), which is used as a controller. The novel photonic sensor was prepared to detect the testosterone by using a straightforward, inexpensive, efficient technique. UV-Visible is used to identify the testosterone depend on Bragg diffraction in a various concentration (100 ppb-5ppb), which is within the normal range in adult males. The detection limit was determined to be 4.2 ppb (S/N=3). The selective adsorption ability of the sensor towards testosterone was investigated by binding experiment with other structural analogs. The photonic sensor showed high selectivity and recoverability in at least 5 cycles of operation and regeneration.

09:40
Victoria Morgan (University of Florida, United States)
Kelli McCourt (University of Florida, United States)
Dianna Vanegas (Universidad de Valle, Colombia)
Irene Velèz-Torres (Universidad de Valle, Colombia)
Lisseth Casso-Hartmann (Universidad de Valle, Colombia)
Eric McLamore (University of Florida, United States)
Low-cost, facile, and rapid nanosensors for establishing a participatory monitoring program on mercury exposure in rural Colombia.

ABSTRACT. Mercury is a dangerous neurotoxin that can cause a plethora of health effects at very low levels (as low as 6 ppb in drinking water). These effects are often heightened in rural and disadvantaged populations where they have less control over environmental and occupational exposure and lack the resources to monitor mercury pollution. Although necessary for validation, standard laboratory techniques to test water (e.g., atomic adsorption spectroscopy) are accurate but are excessively expensive and impractical due to the advanced instrumentation, complex training, and the analysis time. Here, we demonstrate the development of low-cost, facile, and rapid electrochemical nanosensors for mercury determination with the reference, counter, and working electrode fabricated on one sensor strip using flexible carbon circuits decorated with nanocuprous oxide recovered from recycled material. Electrodes were fabricated by laser scribing polyimide, and the working electrode was functionalized by anchoring copper nanoparticles using a novel magneto-hydrodynamic deposition process for creating carbon-metal nanohybrid structures. The material properties, electrochemical behavior and sensor performance were analyzed via scanning electron microscopy, cyclic voltammetry, and linear sweep stripping voltammetry. Mercury sensors were linear from 0 - 1000 ppb, with a limit of quantitation of 7 ppb, response time of 3 min, and sensitivity of 300 pA-ppb-1. The methods for developing the carbon nanosensors do not require specialty equipment, are facile, economic, and quick, which makes this method practical for development in rural areas. Fabrication and use of sensors represents a new paradigm in participatory monitoring for vulnerable rural communities in Cauca, Colombia

10:00
Anna Doloman (Utah State University, United States)
Ronald Sims (Utah State University, United States)
Charles Miller (Utah State University, United States)
Algalytic bacteria increase methane production during anaerobic digestion of algal biomass

ABSTRACT. Anaerobic digestion of microalgal biomass cannot be achieved without specialized hydrolytic microorganisms. Potentially algalytic bacteria belonging to Citrobacter and Alcaligenes species were isolated from a wastewater lagoon system. A combination of two potentially algalytic bacteria was successfully incorporated into the granular anaerobic consortia. A series of anaerobic cultures were prepared with different microbial combinations to test the methane production from algal biomass collected from a local wastewater treating trickling filter. The anaerobic microbial community mixed with two algalytic bacteria produced 10% more methane when compared to the methane produced by a native granular consortium. The presence of the algalytic bacteria of interest was confirmed by PCR using bacteria specific primers at the conclusion of the study. A computer-simulated model was designed to prove the possibility of incorporating algalytic bacteria into a mature methane-producing granule.

Future research will address the anaerobic degradation potential of the modified granular consortia on other types of the microalgal biomass.

10:20
Jeffrey Crandall (Utah State University, United States)
Increasing biomethane production with the addition of Rotating Algal Biofilm Reactor algae for energy recovery in wastewater treatment

ABSTRACT. Wastewater treatment requires a great deal of energy to be input into the system. The treatment process at Central Valley Water Reclamation Facility (CVWRF) in Salt Lake City UT currently includes anaerobic digestion of biosolids to create biomethane that is converted to electricity through regenerative engines. They are currently producing about ½ of their energy through anaerobic digestion. Methanogens in an anaerobic state consume carbon and nitrogen to produce the biomethane. This experiment looks to increase the biomethane potential through the addition of carbon and nitrogen. Using Dannon Yogurt whey as a carbon source and microalgae grown on a rotating algal biofilm reactor (RABR) at CVWRF, along with data from previous studies done at Utah State University, further tests are hypothesized to yield more methane. Results of this research will be used to evaluate the effect of microalgae on enhancing bioenergy production through anaerobic digestion of biosolids produced during wastewater treatment.

12:30-14:30 Session 11A: Bioethics Essay & Student Design Competition
Chairs:
Asif Rahman (Zymergen, United States)
Keith Roper (University of Arkansas, United States)
12:30-14:30 Session 11B: Metabolic Engineering
Chair:
Ryan Summers (The University of Alabama, United States)
12:30
Gary Zhan (Logan High School, United States)
Fuchao Xu (Utah State University, United States)
Enhanced production of indigoidine using a cold-shock inducible promoter

ABSTRACT. Dyes are commonly used in our everyday life and can be found in almost everything we use including toys, clothing, paper, food, cosmetics and drinks. Most of the dyes used today, however, are chemically synthesized, which often requires the use of toxic reagents and harsh conditions, causing serious environmental issues. Additionally, consumption of synthetic dyes can also cause health problems such as allergy and cancer. Natural dyes are from nature and represent a promising alternative. However, industrial production of natural dyes is challenging due to the need of large farm land and low production yield. Indigoidine is a new natural blue dye from bacteria with interesting health-benefiting properties (anti-oxidative and antimicrobial).

The previous indigoidine-producing plasmid uses the T7lac promoter, which suffers leaky expression, where residual lactose activates the promoter and triggers the expression of the indigoidine synthetase when the cells are still growing at 37 degrees Celsius. Since the indigoidine synthetase can only fold correctly to be functional at low temperatures, leaky expression wastes a lot of resources that otherwise can be used for indigoidine production. In this work, I introduced the cold-shock inducible cspA promoter into the indigoidine biosynthetic system, tested how the promoter functions at different temperatures, and compared the production titers of indigoidine in this cold-shock inducible system with the previously used T7lac system. My results showed that this new system worked best at 18 degrees Celsius among the three tested temperatures and the production of indigoidine was increased by approximately 28% compared to the previous system.

12:50
Baviththira Suganthan (Nano Electrochemistry Laboratory, School of Chemical, Materials and Biomedical Engineering, University of Georgia, United States)
Chang-Hao Wu (Department of Biochemistry and Molecular Biology, University of Georgia, United States)
Dominik K Haja (Department of Biochemistry and Molecular Biology, University of Georgia, United States)
Yi Fang (Nano Electrochemistry Laboratory, School of Chemical, Materials and Biomedical Engineering, University of Georgia, United States)
Michael Ww Adams (Department of Biochemistry and Molecular Biology, University of Georgia, United States)
Ramaraja P Ramasamy (Nano Electrochemistry Laboratory, School of Chemical, Materials and Biomedical Engineering, University of Georgia, United States)
Electricity Generation by Genetically Engineered Hyperthermophiles

ABSTRACT. Pyrococcus furiosus (Pf) is considered as a potential microbial catalyst for use in the anode of microbial fuel cells (MFCs) [Sekar et al. (2017)]. Pf consists of two main enzymes namely membrane bound hydrogenase (MBH) and cytoplasmic soluble hydrogenase (SH), which are involved in its oxidative fermentative pathways. However, in anaerobic respiratory systems, the pathways of electron transfer between the oxidative fermentative pathways and the activity of MBH and SH is not fully understood (Sapra, 2000). In this study, we hypothesize that genetically manipulating the expression of SH and MBH could lead to enhanced extracellular electron transfer ability, which could be characterized by enhanced reduction activity of Pf towards soluble and insoluble iron species which also benefits electricity generation. Pf is used as anode catalyst in microbial fuel cell. In this study, naturally competent Pf strain (COM1) was genetically engineered to produce strains that over expressed SH1 (OESH1) and MBH (OEMbhJ-N) and that lacked both SH1/SH11(ΔSHI/II) and MBH (ΔMbhL). Soluble ferric citrate (citrate) and insoluble Fe2O3 (oxide) were used to investigate the ability of engineered Pf strains to reduce the extracellular oxidants. In addition, Pf was used as the anode catalyst in a two-chamber microbial fuel cell setup to study its exo-electrogenic ability towards electricity generation. Experiments revealed that the ΔMbhL strain, produced the highest exo-electrogenic ability among the various Pf strains tested. To the best of our knowledge this is the first paper which compares the electrical current generation ability of different strains of genetically engineered Pf.

13:10
Shelby Brooks (The University of Alabama, United States)
Ryan M Summers (The University of Alabama, United States)
Characterization of the truncated caffeine N-demethylase reductase NdmD isolated from Pseudomonas putida CBB5

ABSTRACT. Pseudomonas putida CBB5 can metabolize caffeine and related methylxanthines to xanthine using five enzymes, NdmABCDE. NdmABC are N¬1-, N3-, and N7-specific N-demethylases that belong to the Rieske oxygenase family. NdmD serves as the sole Rieske oxygenase reductase for this set of enzymes. The purpose of NdmD is to transfer electrons from NADP(H) so the N-demethylation reactions can occur. NdmD contains an additional Rieske 2Fe-2S cluster at its N-terminal end, unlike any other known Rieske reductase. The 2Fe-2S cluster appears to be a fusion from NdmC, which lacks a Rieske domain but contains the N7-demethylation catalytic site. The C-terminal end of NdmD matches other FNRC-type Rieske reductases, with a FAD/FMN binding domain, an NADH binding domain, and a 2Fe-2S plant-type ferredoxin domain. The hypothesis is that the Rieske 2Fe-2S domain on NdmD is used in conjunction with the Rieske-less NdmC enzyme and structural subunit NdmE to carry out the N7-demethylation of 7-methylxanthine, but is not required for enzymatic activity of NdmA and NdmB. A truncated NdmD lacking the N-terminal Rieske cluster, was cloned into pET28a(+) E. coli expression plasmid containing an N-terminal hexahistidine tag and named NdmDP1. NdmDP1 and the wild type NdmD were expressed and purified from E. coli cultures using a nickel affinity column. Cytochrome c reductase and N-demethylase enzymatic assays were performed using the purified reductase enzymes in conjunction with NdmA and NdmB. Results indicate that the N-terminal Rieske 2Fe-2S cluster are not necessary for activity of NdmA or NdmB, but is a necessity for NdmC activity.

13:30
Fuzhong Zhang (Washington University, United States)
Regulating metabolic pathways and microbial subpopulations for chemical and biofuel production

ABSTRACT. Engineering microbial metabolic pathways offers the opportunity to produce renewable fuels, chemicals and materials. For this technology to be economically viable, engineered microbes must produce target compounds in high titers, yields, and productivities. Microbes evolved sophisticated regulatory network to adapt to various environments for cell growth, but not to produce chemicals in large quantities and with high efficiencies. To improve microbial production, we developed sensor-regulators to dynamically control the expression of pathway genes, which balance the metabolism of heterologous pathways and prevent the accumulation of intermediates to toxic levels. We also develop sensor-selectors to continuously select for high-performing, non-genetic variants within iso-genetic populations. Using the designed synthetic regulatory systems, we have demonstrated significantly improved product titers, yields, productivities and genetic stability on multiple biosynthetic pathways. Design principles of these synthetic regulatory systems should be useful in other areas of biotechnology, enabling new avenues of research and applications.

13:50
Ozkan Fidan (Utah State University, United States)
Yonghong Liang (Utah State University, United States)
Jixun Zhan (Utah State University, United States)
Bio-halogenation of flavonoids by a fungal flavin-dependent halogenase

ABSTRACT. Flavonoids are found in vegetables, fruits, tea, honey and wine, and have shown various health-benefiting biological activities such as anticancer, antiviral, antioxidant, anti-inflammatory and antimicrobial effects. Halogenated molecules account for about a quarter of pharmaceuticals on the market or in the development pipeline. However, halogenated flavonoids are rare in nature. Chemical halogenation was used to prepare halogenated derivatives with improved biological activities. For instance, compared to chrysin and other tested flavonoids, halogenated chrysins have indicated stronger antiviral activity against dengue and Zika virus. While chemical halogenation is limited by its poor selectivity and harsh reaction conditions, bio-halogenation represents a green and effective method to prepare halogenated compounds. In this study, we conducted the biotransformation of flavonoids in engineered Escherichia coli BL21(DE3) expressing fungal flavin-dependent halogenase (Rdc2). We successfully halogenated chrysin, quercetin, naringenin and hesperetin to yield a series of halogenated flavonoids. The purified halogenated flavonoids were characterized with LC-MS and NMR. This work represents the first report of preparation of halogenated flavonoids using flavin-dependent halogenases.

14:10
Po-Cheng Lin (Washington University in St. Louis, United States)
Fuzhong Zhang (Washington University in St. Louis, United States)
Himadri Pakrasi (Washington University in St. Louis, United States)
Sustainable production of sucrose in the fast-growing cyanobacterium Synechococcus elongatus UTEX 2973

ABSTRACT. Cyanobacteria are photosynthetic bacteria that use sunlight and CO2 for growth. Direct conversion of CO2 to desired products makes them attractive platforms for sustainable production of chemicals. However, the major challenge of using cyanobacteria for chemical production is the low productivity compared to that from the heterotrophic microorganisms such as E. coli and yeast. This is presumably due to the slow growth rates of standard laboratory strains of cyanobacteria. In this work, we engineered the fast-growing cyanobacterium Synechococcus elongatus UTEX 2973 for sugar production. With salt stress, cyanobacteria synthesize sucrose as an osmotic protectant to avoid desiccation. To develop a sucrose-exporting cyanobacterium, the H+/sucrose symporter cscB was introduced into Synechococcus 2973. Under salt induction, the cscB-expressing strain produced 8.1 g L-1 of sucrose, with a productivity over 1.5 g L-1 D-1. The majority of sucrose was produced in the stationary phase, with 90% of the fixed CO2 directed to sucrose production instead of cell biomass. Moreover, to expand the applications of sucrose production, Synechococcus 2973 was engineered to produce sucrose without salt stress. By expressing genes in sucrose synthesis, the mutant produced sucrose with a productivity over 1 g L-1 D-1 in normal BG11 medium. This work demonstrates the potential of using Synechococcus 2973 for sugar production.

14:45-16:45 Session 12A: Biomedical Engineering - Biomechanics
Chairs:
Gary Bledsoe (Saint Louis University, United States)
Ferris Pfeiffer (University of Missouri, United States)
14:45
Lydia Webster (Southeast Missouri State University, United States)
Eswara Priyanka Nalla (Southeast Missouri State University, United States)
Shamik Bhattacharya (Southeast Missouri State University, United States)
Mechanical Properities of atria and annulus in raidal and circumferential direction

ABSTRACT. Mechanical properties of the cardiac tissue play an important role in normal heart function. The goal of this study was to determine the passive mechanical properties of atrial and annulus tissue in both radial and circumferential direction. This information will be useful to develop new banding procedures for tricuspid and mitral annulus. Annulus dilation is an important feature in both tricuspid and mitral valve disease. The existing techniques do not have long term durability and non-percutaneous. The mechanical compatibility of atrial and annulus tissues will be very important to develop new banding techniques for valvular diseases.The right and left atrium tissue, tricuspid and mitral annulus tissue of porcine and ovine hearts was separated into a free wall segment and a septal wall segment. Uniaxial tensile tests (Ustretch-Cell Scale) were done with strips of tissues . Imaging technique was used to calculate strain. Tests were done in both, circumferential and radial direction. The tissues were stretched until they presented the first sign of failure, which was indicated by a drop in the magnitude of force required to stretch the tissue. Stress was obtained using the equation: Stress = Force ÷ (thickness x width). The strain was quantified using the displacement of the markers from the imaging techniques. Preliminary data shows tricuspid atrial tissues and tricuspid annulus septal tissue have similar mechanical properties in both freewall and radial direction. The mitral annulus freewall also has similar mechanical properties with tricuspud atrial tissues.

15:05
Muhammad Salim (University of Missouri, United States)
Ferris Pfeiffer (University of Missouri, United States)
Effect of Stress Relaxation Time on Parameter Optimization Using Finite Element Simulation

ABSTRACT. Osteoarthritis is one of the leading forms of arthritis, which affects about 52.5 million people. Arthritis causes severe pain and can decrease quality of life. It cannot be reversed but understanding how cartilage slowly degrades could lead to earlier diagnosis and treatment, before joint replacement is necessary. Overall, computational modeling can help accurately predict disease progression.

Cartilage health is affected by mechanical properties, therefore it is important to know the influences of such factors. The time constraints of stress relaxation testing limited previous efforts to study articular cartilage in various stages of osteoarthritis. In previous studies, stress-relaxation tests required cartilage to be indented for over 3 hours per sample. This caused issues regarding deterioration of cartilage samples as well as inefficient testing. To solve this, we chose to implement a computational approach using the open source software FEBio (FEBio.org) and demonstrated negligible error when predicting cartilage mechanical properties compared at 120s, 300s, 1000s, 5000s, and 10000 seconds.

The use of FEBio allowed for an increased testing efficiency and maintained cartilage viability such that the tissue could be used in further testing. From the FEBio computational modeling, we could evaluate stress-strain response, static and dynamic loads, and extract material properties from stress relaxation indentation tests in under 5 minutes.

15:25
Jacob Crapps (Saint Louis University, United States)
Natasha Case (Saint Louis University, United States)
Design and Fabrication of a Novel Ultrasound Bioreactor

ABSTRACT. Daily application of low intensity pulsed ultrasound (US) has been shown to induce cellular responses supporting bone repair, yet the bioeffects of this stimulus are poorly understood. A bone healing site is a three-dimensional (3D) volume, and US propagation within such a space is complex. In vitro studies in 3D models, such as cell-seeded scaffolds, are therefore needed to investigate cellular mechanisms induced by US. Such studies are influenced by conditions within the US bioreactor. Commonly used bioreactor designs include an air-liquid interface in the direct path of US wave propagation. Wave reflection will occur at this interface, leading to the formation of standing waves that increase variability in the pressure within the bioreactor. The purpose of this study was to develop and characterize a novel bioreactor configuration for US stimulation of cell-seeded scaffolds that eliminated air-fluid interfaces. An enclosed sample holder was designed and fabricated, and the holder was combined with an acoustic absorbent material. The holder had a centrally located inner well filled with culture medium for containment of a cell-seeded scaffold. The US transducer was immersed in water and positioned below the sample holder. The acoustic pressure in the fluid domains of the US bioreactor was evaluated by developing a finite element model and conducting multiphysics simulations in the frequency domain. The effects of individual configuration parameters (i.e. thicknesses of the water and culture medium layers, radius of the inner well) on spatially-averaged acoustic pressures were analyzed to produce an optimized configuration for future cellular studies.

14:45-16:45 Session 12B: Bionanotechnology
Chairs:
Keith Roper (University of Arkansas, United States)
Silviya Zustiak (Saint Louis University, United States)
14:45
Nicholas Schaper (Saint Louis University, United States)
Brannan Hutchinson (Saint Louis University, United States)
Silviya P Zustiak (Saint Louis University, United States)
Irma Kuljanishvili (Saint Louis University, United States)
Designing new nano-biocomposite materials using CNTs and ZnO hybrid interfaces and hydrogel environments for biomedical applications

ABSTRACT. One dimensional (1D) nanoscale objects such as carbon nanotubes or other nanowires represent a unique opportunity for utilizing their large surface area and high aspect ratio. Therefore,1D nanowires can be functionalized through their entire length with specific biological molecules or other nanoscale moieties via covalent bonding, physisorption or chemisorption. Dimeters of 1D nanowires range from 1-5 nm, in carbon nanotubes (CNTs), and 50-100 nm in zinc oxide nanowires (ZnO NW), hence they are great candidates for biomedical applications, due to unique morphological, electronic properties and biocompatibility. For example, they provide nano-textured surface for molecular immobilization, enhance electrical conductivity in the composite materials, when incorporated into nonconductive environments, could improve the mechanical strength of composite materials and be used as power lines for transmitting electrical signals to biological cell for stimulation/recording. The goal here is to investigate the use of CNTs and ZnO NW in composite biomaterials and as hybrid new platforms for applications including neural tissue engineering, therapeutics for targeted cancer treatments, biosensors, short term implants, or prosthetics. In this work we investigate single-walled (sw)-CNTs and multi-walled (mw)-CNTs as well as ZnO NWs and CNTs/ZnO composite hybrid structures as surfaces that could interface with other biomaterials such as hydrogels. The sw-CNTs/hydrogels interfaces have demonstrated great potential in facilitating healthy neuronal cell behaviors, such as cell attachment, proliferation and neurite growth. Designing new ZnO/Hydrogel and CNTs/ZnO/Hydrogel composites could expand medicinal benefits of these nano-biomaterials in targeting multiple medically important questions such as neural cell regeneration, cancer treatments, drug delivery and other.

15:05
Sourav Chakraborty (Southeast Missouri State University, United States)
Htet Linn (Southeast Missouri State University, United States)
Santaneel Ghosh (Southeast Missouri State University, United States)
Microbial Growth Response to Highly Water Dispersible Boron Nitride Nanotubes

ABSTRACT. Boron nitride nanotubes (BNNTs) have characteristically high degree of chemical and thermal stability, are less cytotoxic than carbon nanotubes (CNTs), and possess excellent piezoelectric properties; making them an extremely attractive candidate for potential biomedical applications. However, several issues (e.g., poor dispersibility, agglomeration in the intracellular environment) limit the use of BNNT based systems for biomedical applications. In this study we report the biocompatibility of surface functionalized water dispersible BNNTs on Escherichia coli (E. coli) bacteria. In the present work, E. coli growth was monitored as E. coli served as a representation of how cells might respond in the presence of surface functionalized water dispersible BNNTs in their growth environment. In the presence of surface functionalized well dispersed BNNTs (dia.≥50nm), the E. coli growth curves were generated in 5 mL of LB media (up to a concentration of 1200 µg/mL of suspended BNNTs). Data has been generated based on time (0-300 min) dependent growth kinetics of the E. coli bacteria. From the growth curves, there was no evidence up to a concentration of 600 µg/mL of suspended BNNTs that prevents the microbial cells from growing; however, at a considerably higher concentration (1200 µg/mL), microbial growth was inhibited, which was expected. This indicates up to a concentration of 600µg/mL in the culture media, BNNT reveals excellent biocompatibility with the bacterial cell model. This finding is especially promising where higher amount of BNNTs are needed in the intracellular environment, for example, gene delivery through electroporation.

15:25
Brannan Hutchinson (Biomedical Engineering, Saint Louis University, United States)
Mozhdeh Imaninezhad (Biomedical Engineering, Saint Louis University, United States)
Fenglian Xu (Biology, Saint Louis University, United States)
Irma Kuljanishvili (Physics, Saint Louis University, United States)
Silviya Zustiak (Biomedical Engineering, Saint Louis University, United States)
Carbon-nanotube-polyethylene glycol nanocomposite biomaterials as neural substrates

ABSTRACT. Carbon nanotube (CNT)–hydrogel composites are attractive for a variety of neural tissue engineering and drug delivery applications as well as biosensor coatings, transducers and leads. Both materials contribute unique and beneficial properties to the composites. Hydrogels are an excellent mimic of the extracellular matrix due to their hydrophilicity, viscoelasticity and biocompatibility. CNTs, on the other hand, can impart electroconductivity to otherwise insulating materials, improve mechanical stability and guide neuronal cell behavior as well as elicit axon regeneration. In this research, two different polyethylene glycol (PEG) hydrogels were developed with either powdered Multi-Walled CNTs (MWCNTs) entrapped in the hydrogel or imprinted Single-Walled CNTs on the surface of the hydrogel. The hydrogel crosslinking reaction is based on Michael-type addition which is ideal for in situ cell and protein encapsulation. To adequately disperse the highly hydrophobic powdered MWCNTs in the aqueous polymer solution, we used sonication and surfactants, where bovine serum albumin was found to be an effective and non-cytotoxic dispersant. SWCNTs were grown on silicon oxide substrates using chemical vapor deposition, and a novel two-step method was used to transfer SWCNTs from the substrates onto the hydrogels. PC12 cells were seeded on both MWCNT- and SWCNT-hydrogel substrates as well as PEG on as control. Upon incubation, cells were fixed, immunofluorescent stained and imaged to observe and compare cell morphology and physiology. By staining beta-tubulin and synapses, the neural morphology was detected in high resolution through fluorescent imaging. Our goal is to design nanocomposite hydrogels to direct neural cell regeneration.

15:45
Donald Roper (Utah State University, United States)
Optoelectronic plant leaf sensors with nanoantenna

ABSTRACT. Sustainable use of land, water, and energy resources is imperative as evolving stresses and expanding needs put increasing demands on agricultural productivity. Stress-resilient cultivars and decision support systems (DSS) for sustainable intensification in precision agriculture to manage irrigation, fertilizer, pests and pathogens could mitigate such factors. But gaps like sparsity of data to phenotype plants and barriers like cost and information deficit preclude systematic plant modeliing. One result is that data from small-scale physiological studies and field-based yield assessments often do not match.

This work examines optoelectronic plant leaf sensors based on nanoantenna. Nanoantenna exhibit tunable effective refractive index due to composition, geometry and arrangement. Neighboring meta-atoms that support near-field plasmons may couple via far-field phase-coherent radiation. Plasmon interactions are limited to resonance wavelengths and only occur in close proximity to plasmon-active nanostructures. But far-field coupling provides across large spectral regionsm tunable by 2D structuring of neighboring metaatoms. This has potential for sensing components involved in plant photosynthesis, e.g., H2O and CO2.

This work examined nanoantenna metasurfaces using (1) multi-scale models to evaluate plasmon-photon coupling and design nanoantenna metasurfaces; and (2) novel methods to fabricate nanoantenna metasurfaces analyzed by optical and electron microscopy. We will present physicochemical, geometric, and electromagnetic effects on spectral response by nanoantenna metasurfaces. Interactions between dynamic polarizability and constructive interference suggest nanoantenna metasurfaces can provide delocalization of plasmon effects as well as tunability across the electromagnetic spectrum to permit far-field, broad-spectrum, plasmon enhancement useful for in planta sensing.

16:05
Kyle Vogt (Saint Louis Univeristy, United States)
Mozhdeh Imaninezhad (Saint Louis University, United States)
Dzhuliya Vasileva (Saint Louis University, United States)
Mark McQuilling (Saint Louis University, United States)
Silviya Zustiak (Saint Louis University, United States)
A Simple Microfluidic Device for the Production of Monodisperse Hydrogel Microspheres

ABSTRACT. Micron sized monodisperse hydrogel particles have wide applications in biotechnology: from serving as sustained drug delivery carriers or drug testing platforms, to providing scaffolding for cell growth. Current methods for creating microparticles are complex, expensive, labor-intensive, and require specialized equipment to fabricate. There is a need for cheap, easy, and reliable methods for creating hydrogel microspheres that enable the preparation of microspheres of diverse sizes in a narrow size distribution. By utilizing a microfluidic method that employs polymeric tubing, programmable syringe pumps, syringes, and a collection vessel, we developed a simple and inexpensive method to prepare uniform particles in a wide range of diameters. To create spheres, a hydrogel precursor solution was injected into one end of a polymeric tee junction while olive oil was injected into the other end. Due to the immiscible nature of the two liquids, an oil and water emulsion was created where the olive oil served as the continuous phase, and the hydrogel polymer served as the dispersed phase. Flow rates for both phases were controlled by syringe pumps and were varied while keeping the flow rate of the opposite phase constant. Microspheres from 91 to 472 μm in diameter were produced. Percent coefficient of variance (%CV) was between 6.1% and 48.4% depending on the condition tested. High %CV was attributed to coalescence of PEG droplets upon collection. Ongoing work is focused on fabricating radio-opaque microspheres to allow for in vivo imaging of drug eluting microparticles.

16:25
Zach Hancock (Southeast Missouri State University, United States)
Jacob Seabaugh (Southeast Missouri State University, United States)
Caleb Ellenburg (Southeast Missouri State University, United States)
Sidney Siebert (Southeast Missouri State University, United States)
Santaneel Ghosh (Southeast Missouri State University, United States)
Derek Yarbro (Cardinal Biological, United States)
Interaction between nano-particle covered carbon nano-tubes and human blood

ABSTRACT. Surface functionalized multifunctional nanostructures are being developed as potential drug carriers for specific tumor targeting and/or central nervous system disease related treatment. These nanocarriers can be loaded with single or multiple therapeutic agents and can be designed to release the therapeutic agents gradually, on demand at target locations. Since the nanocarriers must be designed for systemic administration, the hemocompatibility of the nanocarriers is a crucial factor that must be considered. In this work, we have evaluated the intracellular uptake and the hemocompatibility of these nano-carriers.

A multifunctional magnetite (Fe3O4)/Gold (Au) nanoparticle (NP) decorated dextran covered carbon nanotube system (NP-CNTs) was synthesized. For neurite outgrowth evaluation, PC12 neuronal cells were cultured for 72 hours and then exposed to the NP-CNT serum for 3 days in presence of beta NGF. The hemocompatibility of the nano-carriers was evaluated with a focus on hemolytic activity and blood coagulation. Upon fixation, cell morphology was observed by performing optical and scanning electron microscopy.

The designed nanocarriers were externally tunable and were internalized efficiently by PC12 cells, resembling positive control conditions when exposed to NP-CNT concentration up to 200μg/mL. Results also indicated minimal hemolysis with concentrations up to 200µg/mL for the nano-carriers. In vitro human red blood cell lysis percentages ranged from 0.74 – 4.00% of complete hemolysis from our positive control.

The data indicates that these nano-carriers have potential blood compatibility at various doses. Our results show that these nanocarriers have great potential in the field of cancer treatment and treatment for neurological damage.

17:00-18:00 Session 13: Poster Session
Chairs:
Maxine Jonas (MIT, United States)
Aj Walters (Utah State University, United States)
17:00
Hui-Yuan Chen (Washington University in St. Louis, United States)
Michelle Liberton (Washington University in St. Louis, United States)
Dariusz Niedzwiedzki (Washington University in St. Louis, United States)
Himadri Pakrasi (Washington University in St. Louis, United States)
Potential strategy to increase the quantum yield of photochemistry via the control of a redox switch in an antenna protein

ABSTRACT. Cyanobacteria are photosynthetic microbes that are able to harvest light energy for conversion into chemical energy. IsiA is a cyanobacterial chlorophyll a-binding protein induced by iron deficiency and other stress conditions. It serves as an accessory light harvesting antenna of photosystem I (PSI) when it is coupled with PSI and forms PSI-IsiA supercomplexes. Without PSI, IsiA forms ring-shaped aggregates that absorb light energy and dissipate it via a non-photochemical process to prevent photosynthetic proteins from photodamage. The mechanism of excitation energy quenching in IsiA involves a cysteine-mediated process similar to the protein-pigment interactions regulating the light harvesting capabilities of the FMO protein in green sulfur bacteria. Interestingly, the addition of reducing agents hindered energy quenching in IsiA, indicating that this excitation energy quenching process is highly depending on the local reduction potential. In addition, mutant phenotypes showed that the modification of single amino acids substantially affects the quantum yield of photochemistry, resulting in distinct growth profiles. These results suggest that by adjusting the local reduction potential, the quantum yield of photochemistry may be tuned, which can be used as a novel strategy to improve the biomass productivity of phototrophic organisms.

17:00
Kyle Hillman (Utah State University, United States)
Struvite formation influenced by microalgae biofilms

ABSTRACT. Struvite (magnesium ammonium phosphate) is a granular nutrient precipitate common after anaerobic digestion of municipal waste. Struvite causes inefficiencies in wastewater treatment systems due to scaling and clogging in belts, pipes, pumps, and other equipment downstream of anaerobic digestion. However, struvite is a valuable product if harvested for use as a fertilizer. While using a rotating algal biofilm reactor (RABR) for tertiary treatment of anaerobic digester pressate, struvite formation was observed on RABR discs. Promoting struvite formation on RABRs could enhance nutrient removal from wastewater and provide an opportunity to generate valuable fertilizer products. A controlled study was set up to understand how humidity, temperature, pH, and presence of microalgae influence struvite formation in biofilms.

17:00
Jake Accordino (Utah State University, United States)
Analysis of Productivity and Characterization of Microalgae Grown on Bioreactor for Wastewater Remediation

ABSTRACT. The present study investigates the effectiveness of Rotating Algae Biofilm Reactors (RABRs) in the treatment of municipal wastewater through the growth of microalgae species, and examines the factors impacting said growth. The release of nutrients found in wastewaters, namely nitrogen and phosphorous, into the environment leads to eutrophication within receiving ecosystems, causing harmful algal blooms and upsetting aquatic life. Current methods implementing biological treatment for removing these nutrients require large amounts of available land. RABRs mitigate this challenge of limited space by providing upright substrates for the growth of biofilms. Plastic disks serving as the biofilm substrates are placed upright on an axle, half submerged in wastewater, and rotated at low velocities. Microalgae biofilms on the disks remove nitrogen and phosphorous as they rotate through the wastewater. Uptake of these nutrients is directly proportional to biofilm growth, making it important to understand the factors associated with biofilm productivity. This study seeks to determine the effect of biofilm substrate material, ambient temperature, and photosynthetically active radiation (PAR) on the productivity and diversity of the microalgae cultures present within a RABR. It is expected that beyond a certain observed threshold, productivity and diversity of microalgae biofilms will decrease due to overexposure of light and heat. Further, polystyrene foam disks are predicted to be the material most conducive to biofilm formation and species diversity.

17:00
Han Zhang (Utah State University, United States)
Wei Zhang (Utah State University, United States)
Anhong Zhou (Utah State University, United States)
A Smartphone, Paper-Based Optical Platform for Whole Blood Glucose Colorimetric Assay

ABSTRACT. In this work, a smartphone, paper-based optical detection platform is designed and fabricated for colorimetric analysis of blood glucose. The paper-based device was fabricated by wax printing, and the TMB substrate and GOx/HRP bio-enzymatic system were inkjet printed as the sensing zone of the chromatography filter paper. The membrane filter was then laminated on top of the chromatography paper for blood separation and glucose in plasma penetrate to the sensing zone on chromatography paper resulting in a color change from TMB substrate upon the glucose induced GOx/HRP enzymatic reaction. The result color image was analyzed by a developed Android App using an integrated camera in the smartphone. To avoid the effect of ambient light, a 3D printed optical chamber was included in this platform. With the image-processing program on the smartphone, the developed device was successfully applied to determine various glucose levels of blood from 0.05mg/ml to 4mg/ml, which covers the range of human normal blood glucose concentration 0.5 mg/ml to 2mg/ml. The limit of detection (LOD) obtained from the developed platform was 0.05mg/ml. The glucose concentration in blood could be conveniently and accurately determined using this system, and it provides great potential to be used as a powerful point of care (POC) diagnostic tool for blood or urine glucose monitoring.

17:00
Yiming Liu (Washington University in St. Louis, United States)
Linhua Xu (Washington University in St. Louis, United States)
Guangming Zhao (Washington University in St. Louis, United States)
Xuefeng Jiang (Washington University in St. Louis, United States)
Lan Yang (Washington University in St. Louis, United States)
Emerging Optical Materials for Whispering Gallery Mode Microresonators

ABSTRACT. In the last decade, whispering-gallery-mode microresonators (WGMRs) have been investigated in a broad range of applications from fundamental science to bio-sensing, because of the significantly enhanced light-matter interactions attributed to their high-quality factors and small mode volumes. As WGMRs expanding their applications in new fields, many challenges are induced to hinder the improve of performance. Since materials research provides the foundation for the development of many new technologies, introducing new materials into the materials library of WGRs could be one of the solutions to solve the problems. Yang’s group studies the characterizations and applications of whispering gallery mode microresonators fabricated or coated with unconventional materials. Materials including polydimethylsiloxane, titanium dioxide, lithium-niobate and silk protein have been characterized and tested for specific applications. In this poster, we summarize recent progress of materials research in our group and provide a perspective of the future of emerging materials for Whispering Gallery Mode Microresonators.

17:00
Daniel Bird (Southeast Missouri State University, United States)
Tyler Howard (Southeast Missouri State University, United States)
Jimmy Keng'Ara (Southeast Missouri State University, United States)
Benjamin Nielsen (Southeast Missouri State University, United States)
Adam Stone (Southeast Missouri State University, United States)
Design of a High Frequency Photo-Magnetic Actuator for Biomedical Applications

ABSTRACT. Plasmonic and magnetic heating of multifunctional nanostructures has been explored for potential biomedical applications ranging from controlled drug delivery to hyperthermia-induced cancer therapeutics. Current research has begun to shift from solely plasmonic or magnetic actuation to coupled plasmonic-magnetic actuation of the nanoparticles with few devices capable of achieving dual excitation simultaneously. As part of our capstone design, this work presents an apparatus using an LRC circuit that may be tuned to several different resonance frequencies of oscillation for the magnetic field coupled with optical irradiation at the plasmon frequency of the ferromagnetic/gold nanoparticles. The tunability of the resonance frequencies (125-300 kHz) was provided through two swappable and separate capacitor banks and Helmholtz coils generating desired thermal response of the target. Field intensity control, i.e., the additional regulation of thermal response was provided through a signal generator amplified to the specified voltage for operation of the LRC circuit. Programmability of this apparatus highlights the importance of design for plasmonic-magnetic nanoparticle-based hybrid material excitation devices. This device will be instrumental to extract and characterize the novel nanocomposites (thermal, electrical and magnetic properties), and various therapeutic agents and their efficacy on neural, stem cell, and tumor models. Future improvements for this device are focused on overall system optimization, practical functionality, and an integrated imaging platform for further thermal characterizations.

17:00
Jaehoon Choi (Washington University in St.Louis, South Korea)
Multiplexed Sensing by Two Microtoroid Cavities

ABSTRACT. High-Q WGM resonators provide a platform for on-chip and high sensitivity sensors. The way optical fiber and the microtoroid are coupled is through an evanescent field which allows photons in the waveguide to jump into the resonator. Any perturbation on the surface of the sensor will change the radius of the resonator, thus changing the traveling distance and its resonant light wavelength. Observation of this wavelength shift allows detection of many different signals such as biomolecules, humidity, and temperature. Furthermore, multiplexing, which means putting this device in array, increases generality of the technology. Using the fact that resonance condition is related to the traveling distance, it is possible to put these devices in an array by varying their size. Such system can provide multidimensional sensing and noise filtering for bio-sensing. Setting only one of the multiplexed sensors to sense the target particle allows noise filtering by subtracting transmission data of other sensors from the sensor that detected the target. This technique will highly improve data acquired by the optical sensor and provide powerful platform for wide array of fields.

17:00
Min Hyuck Kim (West Virginia University, United States)
Joonhee Lee (West Virginia University, United States)
Investigation of Electrical Characteristics of Nanoporous GaN for Optoelectronic Neural Recording Probe

ABSTRACT. Optogenetic techniques have become a powerful tool in neuroscience, making it possible to control neuronal activities of targeted neurons by light. However, the light-induced artifacts from the metallic electrode in optical stimulation limits the applications of optogenetics. Gallium nitride (GaN), a wideband gap semiconductor, is optically transparent and electrically conductive. Its chemical stability and mechanical robustness are also desirable for implantable devices. Moreover, it has been widely used in optoelectronic devices such as light-emitting diodes and diode lasers, suggesting an easy integration of active light sources on the probe. In this research, the electrical characteristics of a nanoporous (NP)-GaN structure are studied as a promising neural-recording electrode. Various NP-GaN structures are prepared by electrochemical etching of an n-GaN epitaxial layer in oxalic acid. The porosity and depth of porous layers are easily controlled by the applied voltage and etch time. Electrical impedance spectroscopy in buffered saline solution and equivalent circuit modeling reveals a significant and predictable decrement of an impedance value even below 10% of the initial value at 1 kHz. The pseudo-spike recording under optical stimulation shows minimized electrical artifact and validates the capability and functionality of this novel electrode material as a material platform with great potential for an optoelectronic neural probe.

17:00
Nathan Guymon (Utah State University, United States)
Wastewater Remediation of Anaerobic Digester Effluent by a Rotating Algal Biofilm Reactor

ABSTRACT. Microalgae have been used increasingly in wastewater management as it provides the potential for more sustainable approaches to waste treatment. In addition, microalgae can be used to produce a wide array of bioproducts such as biomethane, fertilizer, and protein feed for animals. In collaboration with Central Valley Water Reclamation Facility (CVWRF) in Utah, a pilot scale rotating algal biofilm reactor (RABR) has been tested over the past year to provide tertiary treatment to anaerobic digester effluent. The RABR consists of rotating discs made of a material designed for microalgae biofilm formation. This operating process addresses many of the limitations of conventional suspended-growth methods by allowing for a smaller aerial footprint, partial dewatering algae during operation, and increasing access to light and nutrients for the attached biofilm. A primary challenge of scale-up and widescale implementation of RABR technology is understanding the effect of nutrient and solids concentrations as well as light availability on biomass productivity. This aspect of the pilot scale project focused on measuring the nutrient uptake and wastewater remediation aspects of microalgae biofilms and investigating seasonal differences. The initial results show significant nutrient uptake both in biomass and struvite formation on the RABR. The discs were shown to be effective in removing both nitrogen and phosphorus from the influent stream. The results obtained from the experiment will aid in the future design of RABRs that experience high nutrient loads such as those found at CVWRF.

17:00
Michael Bender (University of Missouri - Columbia, United States)
Corneila Dittmar (University of Missouri - Columbia, United States)
Malik Woulard (University of Missouri - Columbia, United States)
William Schulze (University of Missouri - Columbia, United States)
Genevieve Jones (University of Missouri - Columbia, United States)
Surgical Needle Counter

ABSTRACT. Surgical bodies, such as a surgical needle, are retained in patients’ bodies after surgical procedures in approximately 1,500 cases a year in the US alone1. This medical mishap poses further medical and financial consequences for not just patient but for the surgeon, hospital, and the entire medical team. For the patient, the retained surgical needle will cause potentially life-threatening health complications and a follow-up surgery is often required. The surgeon, hospital, and any involved medical staff will be culpable for the resulting legal consequences, one of which potentially being the completely preventable loss of life. This is why it is essential that a device which accurately counts surgical needles is designed and developed. Such a device will greatly decrease the potential for human error that occurs while counting needles introduced and needles extracted during surgery. Specifically the device will be able to differentiate between types of needles whether that be size, shape, weight, or all of the above. The parts of the device that will be contaminated throughout the surgical needle disposal process must be disposable. The rest of the device, such as the sensor and device body, will remain uncontaminated. Because it is necessary to keep the operation room neat and uncluttered, it is essential that the device is compact and takes up as little room as possible. In addition, it is important to make the device simple and cost effective while not compromising the accuracy of the counter.

17:00
Dylan Ellis (Utah State University, United States)
Daniel Derrick (Utah State University, United States)
Jenson Walters (Utah State University, United States)
Ron Sims (Utah State Unviersity, United States)
Charles Miller (Utah State University, United States)
Production of Bioproducts from Waste Nutrients

ABSTRACT. New regulations on the concentration of phosphate in the effluent from wastewater treatment plants is posing a difficult problem to overcome. With traditional treatment methods alone, many wastewater plants are struggling to meet the new regulations. One such plant is Central Valley Water Reclamation Facility (CVWRF) in Salt Lake City, Utah. It is the largest treatment plant in the state of Utah processing 50-60 million gallons per day. In the search for a solution to their nutrient problem, CVWRF partnered with Utah Science Technology and Research (USTAR), WesTech Engineering, and the Sustainable Waste to Bioproduct Engineering Center (SWBEC) at Utah State University to examine the potential of algae biofilm cultivation on a rotating algae biofilm reactor (RABR), developed by Utah State. When a nutrient analysis on the cultivated biofilm was conducted by the lab at CVWRF, the concentration and quantity of the nutrients in the biofilm could not be explained by the presence of algae alone. The Redfield ratio for the molar stoichiometry of algae is 16 moles nitrogen to 1 mole phosphorus. The biofilm contained ratios of nitrogen to phosphorus close to 1 to 1. When the disks were stopped from spinning for long enough to dry, for sampling, it was observed that there was struvite (NH4MgPO4) present on the disks. High concentrations of struvite could explain the 1:1 N:P ratio. It is expected that the metabolic activity of the algae is raising the pH of the biofilm, allowing struvite, which has minimum solubility at pH 9, to precipitate.

17:00
Clare Kercher (University of Missouri, United States)
Ian Heck (University of Missouri, United States)
Sarah Gebken (University of Missouri, United States)
Robert Rolette (University of Missouri, United States)
A novel, visual indicator for influenza detection

ABSTRACT. Influenza, more commonly known as “the flu”, is a respiratory illness that spreads easily by inhaling the airborne virus or by direct contact with contaminated surface or person. According to the CDC, the flu results in about 48.8 million cases each year. Despite how common influenza is worldwide, it continues to be deadly for the elderly, children, people with compromised immune systems and people with pre-existing conditions. The current preventative measures are limited to avoiding contact with known contaminated surfaces and people as well as an annual vaccine for the flu. For this reason, there is a need to develop a fast, safe, visual indicator that will work as an accurate, preventative measure for the flu. Synthetic biology has allowed us to design molecular beacon probes that utilize two aptamers that selectively bind to the Hemagglutinin sites of influenza types A and B. In one probe the aptamers will be extended with a reporter expression RNA strand, while the other probe’s aptamer is extended by an activator RNA sequence. Once both probes bind to the influenza virus, the sequences can hybridize which ultimately results in the synthesis of EGFP fluorescent molecules. In the end, this system will be integrated into a medium and designed as a test stick that will visually change color to green once the presence of influenza pathogens have been detected. This allows the user to know the virus is present so that they can take the appropriate prevention measures.

17:00
Yue Dong (Saint Louis University, United States)
Ann Harlos (Saint Louis University, United States)
Allison Paoli (Saint Louis University, United States)
Yan Gai (Saint Louis University, United States)
Prolonged sitting affects somatosensory-evoked N300 and N500

ABSTRACT. Modern professions often involve sitting in a chair over a long period. Potential risks of prolonged sitting include cardiovascular diseases and high stress buildup around the buttock tissue and spine, which may lead to pressure ulcer. Although air-cell based cushions have been designed to reduce the risk, a real-time measure of the user’s internal-stress level is yet to be developed. Theoretically, the sensation of pressure is delivered by the receptors in the buttocks to the brain. Brain responses can be detected from somatosensory cortex by vibrotactile stimulation on the epidermis of the buttocks. Our experiment used electroencephalography (EEG) to investigate the somatosensory-evoked potentials (SEPs) by applying tactile stimulations to the subjects during sitting and recording the evoked EEG signals. Notable changes of negative peaks occurring 300 and 500 ms post stimulus onset (i.e., N300 and N500) can be observed as the sitting durations increased, which indicated elevated tissue stress. In order to extract signal features and determine stress levels, we applied machine learning algorithms to determine if significant changes have occurred. The method can be potentially used to construct brain-controlled cushions that adapt to the subject’s tissue stress over time and ultimately prevent pressure ulcer.

17:00
Jing Wang (University of Missouri, United States)
Neural mechanisms of reward-regulated behavior

ABSTRACT. In the forest, animals avoid foraging regions with depleted resources. Humans take alternative, sometimes risky, pathways in our lives. A major driving force of flexible behavior in living organisms is to maximize the future reward outcome. A body of theoretical and experimental studies point towards the central role of dopamine signal in reinforcement learning, which provides a framework for explaining how reward shapes behavior. However, the neural mechanisms that support deliberate and reward-based regulation of behavior are not well understood. In this study, we trained mice on a task, in which one out of multiple choices would lead to reward in a dynamically changing environment. Animals were invariantly sensitive to the reward by employing an exploration-exploitation strategy. We characterized their behavioral change by relating the choice response time and number of attempted trials to the reward history. We devised a computational model to capture the behavioral observation by taking into account both the recent reward and long-term learning. To investigating the neural substrates of the behavior, we genetically labelled neurons in striatum, a major target of midbrain dopaminergic modulation, via GCaMP viral vector. We implemented a miniature head-mounting fluorescent microscope to monitor the functional calcium activities during different phases of the switching behavior. These advances will shed light not only on the mechanisms of reward shapes behavior, but also on how mis-calibration in the reward system would lead to learning deficits and disorders such as addiction.

17:00
Matthew O'Brien (Saint Louis University, United States)
Ann Harlos (Saint Louis University, United States)
Yue Dong (Saint Louis University, United States)
Allison Paoli (Saint Louis University, United States)
Aaron Sass (Saint Louis University, United States)
Yuktesh Kalidindi (Saint Louis University, United States)
Nicole Bajerek (Saint Louis University, United States)
Yan Gai (Saint Louis University, United States)
Machine learning and eye tracking on motion-evoked EEG signals

ABSTRACT. When a human being is presented with a different image for each eye, the two images compete to determine which image dominants the perception. With two images of similar contrast, the perception normally alternates, which is a phenomenon called binocular rivalry. If one image has a much higher contrast than the other, it will dominate the perception for a longer time, effectively masking the other image. However, it has been shown that the masked image can still affect human perception and emotion. Here we recorded Electroencephalography (EEG) using a 31-channel system in healthy human subjects while they viewed separated images in the eyes through binocular lenses. The control condition consisted of two identical images randomly chosen from a set of five photos. In the binocular condition, one eye was presented with a fixed high-contrast image, whereas the other eye was presented with one of the five photos. Machine learning algorithm was applied to decode which photo has been presented on a certain trial. The sensitivity to the photos was examined and compared across the control and binocular conditions. The goal of the study was to investigate 1) if brain signals showed lower sensitivity to the masked image in the binocular condition than in the control condition, and 2) where the masking by the high-contrast image occurred along the cortical visual pathway.

17:00
Rachel Rinkus (University of Missouri - Columbia, United States)
Trisha Wuestling (University of Missouri - Columbia, United States)
Jay Patel (University of Missouri - Columbia, United States)
Dennis Tran (University of Missouri - Columbia, United States)
Microfluidic Cassette for Aerobic Growth of Microorganisms

ABSTRACT. In today's medical practice, antibiotics are prescribed based on their ability to kill bacteria within the bloodstream of an ideal patient. Each patient receives a dosage based on weight, age, and other generalizing factors instead of on their specific blood bacterial content. Each patient's condition will vary, and will rarely ever coincide with that of an ideal test patient. Therefore, it is imperative for physicians to provide critical precision with prescriptions and their dosages. Depending on the severity of an infection, time could be extremely sensitive and treatment is needed as soon as possible. Currently, standard bacterial samples are extracted and grown in cultures for a day. In order to significantly decrease the time needed to analyze bacterial growth and death rates of various concentrations of differing antibiotics, a new method must be developed. Using a microfluidic cassette, a single input of fluid can be evenly distributed to 16 antibiotic coated channels that will measure the growth and death of bacteria over 4-6 hours rather than an entire day. Building upon previous designs, we will construct a microfluidic cassette that is both chemically and biologically inert, minimizes the evaporation of fluid in all channels, and provides a constant flow of oxygen to all samples for growth. The growth and death rates will be measured by two electrodes that are connected to a circuit board that will translate the signal from analog to digital data allowing analysis in order to determine the most effective dosage and antibiotic for the particular sample.

17:00
Rassam Rassam (Saint Louis University, United States)
Yan Gai (Saint Louis University, United States)
Vahdeta Suljic (Saint Louis University, United States)
Machine Learning and Eye Tracking on Motion-Evoked EEG Signals
SPEAKER: Rassam Rassam

ABSTRACT. Human eyes can smoothly pursue a moving object with a speed up to 100 deg/s. However, the perception of motion can also occur with fixed gaze. This study recorded brain signals using Electroencephalography (EEG), when human subjects were presented with a moving object on a computer. The goal was to examine the sensitivity of EEG signals to motion speeds when the eyes were tracking the objects or fixed. On each trial, a dot appeared at the center of the monitor screen and then moved to a large outer circle in a random direction. In each recording session, the movement had 11 different speeds and each speed occurred three times in a random order. The subject’s eye movements were tracked with Tobii Pro Glasses 2. Meanwhile, a 31-channel EEG was used to record the brain signals. A chinrest was used to prevent head movements. In the Moving condition, the subject was asked to actively track the object’s movement, whereas in the Control condition, the subject was asked to fix their gaze at the center where the dot had initially appeared. Visual evoked potentials with similar positive and negative peaks were identified among the subjects. Machine learning algorithms were then applied to decode the motion speed of the object from the EEG signals. The decoding accuracy was compared across the Moving and Control conditions for each subject. We found that different subjects showed different electrode areas with the best decoding accuracy, as well as different preferences of the Moving vs. Control condition.

17:00
Zahra Eslami (Saint Louis University, United States)
Yan Gai (Saint Louis University, United States)
Robotics Localization and Separation for Selective Auditory Attention in Hearing Aids

ABSTRACT. In the presence of multiple simultaneous sound sources, normal-hearing humans are able to selectively focus on one source, while maintaining awareness of the full auditory space. However, this spatial selectivity in hearing-aid users is impaired. The purpose of this project is to restore spatial selectivity in binaural hearing aids. The localization part of our project is based on a recent robotics algorithm that automatically identifies simultaneous sound sources. It remains unclear, however, whether this algorithm is feasible for hearing-aid applications. In the present study, we constructed a real-time system and assessed speech intelligibility with human listeners when the algorithm was incorporated. In phase I of the study, Sound recorded at the right and left ears was processed in the time-frequency domain using a custom-made short-term Fourier transform algorithm. The amplitudes and phases over multiple 40-ms windows were projected to the complex plane and normalized across the two ears. By clustering the time-frequency points over multiple 40-ms windows, the number of active sound sources at each frequency band was estimated. The magnitude and phase of the center point for each cluster at each frequency band were then used to construct head-related transfer functions to reveal the true source locations. Unwanted sound sources were masked using a binary masking scheme. In phase II, the algorithm will be implemented in real time with human subjects to assess the feasibility of the technique for hearing-aid applications. The speech intelligibility scores will then be obtained from normal-hearing listeners to examine the effect of spatial masking.

17:00
Nosakhare Eke (University of Missouri, United States)
Pediatric Wheelchair Assistive Device

ABSTRACT. Nearly 4 million people over the age of 15 use a wheelchair in the world, and of those people, nearly 18% have a job. This number speaks to the issue that being in a wheelchair may often lead to broader consequences and expenses--needing a nurse, a motorized scooter, or a job that requires little movement are all considerations that must now be accounted for. The financial struggle with the rising costs of healthcare does not make the transition to the wheelchair any easier. Many patients struggle every day on completing the simplest of tasks that they need to perform to carry out their everyday lives such as, going to the bathroom and feeding themselves. It is a huge burden, timely and financially, on families to have to take care of someone in this state. It is crucial to give these patients a way to perform these tasks without continued assistance from nurses and other sources of help. We plan to design an assistive device for a wheelchair, to help these pediatric patients. The device will need to be within the client’s and patient’s constraints while still being fully functional. This includes having brakes and direction controls.

17:00
Helberth Velasquez (ECCI, Colombia)
Veronica Lara (ECCI, Colombia)
Ricardo Jaramillo (ECCI, Colombia)
ORGANIC DERMAL INTRATISSULAR RAHABILITATION SYSTEM

ABSTRACT. The tissue dermal damage is a systemic affectation, of multiple causes, such processes of high bacterial activity, severe traumatism and pathologies such as skin cancer. Causing problems of multi-organ participation, being a complex treatment and a problem throughout the world. Due to the number of victims per year. In the United States there are 5 million people per year with skin cancer. With an average treatment cost of $ 8.1 billion. In Europe, for every 100,000 people, 264 have skin cancer, with a greater number of victims in the male sex. A global study of 62 hospitals and 1974 patients with septic shock from different countries, found a mortality rate of 28.4% due to a poor management of infection processes. SRIDO (Organic Dermal Intratiscular Rabbilitation System) is proposed as a solution to this problem, combining two treatments, thick type I structures of collagen fortified with plant extracts, for dermic- tissular regeneration. And the use of silver nanostructures recovered from iron, for the suspension of primary bacterial activity. Being a tool of multiple application in the dermatological area of ​​rehabilitation.