The Effect of Abrasive Toothpastes and Common Acidic Solutions on Teeth

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Figure 1 Determining the Effect of Phosphate and Lanthanum on the Determination of Calcium. The red boxes represent calcium levels at different concentrations with no phosphate in solution. Phosphate has a suppressing effect on calcium when measuring with the AA, which poses a problem for us because calcium and phosphate are both found in teeth, and will both be in our solutions. This is shown by the green triangles, which represent a solution with both calcium and phosphate. We hope to solve this problem by adding lanthanum to the solutions; lanthanum counteracts the suppressive effect of phosphate and will allow us to take a better reading of the calcium concentrations of our solutions.

We (Dr. Stratton along with Clarissa Hunzeker and Malik Thalji) have been researching the effect of abrasive toothpaste on teeth. Specifically, we are measuring the amount of calcium and phosphate (the main components of tooth enamel) eroded away by the extended use of abrasive toothpaste. We will accomplish this by obtaining pig teeth, brushing them with different abrasive toothpastes, placing them in a synthetic saliva solution, and measuring the calcium and phosphate concentrations of the solution over time.

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Malik measuring calcium concentrations using the AAS

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Figure 2 This graph shows the concentration of phosphate compared to the response peak areas in standard solutions. One of the sets of standards contained calcium (green), in order to mimic the solutions with dissolved teeth. The calcium may suppress the phosphate calibration slightly, so this will have to be accounted for when we test our solutions

Additionally, we will test the effect of common acidic solutions, such as coffee, soda and wine on teeth. We will measure the calcium and phosphate concentrations to determine the effect of each acidic solution. We will use atomic absorbance spectroscopy (AAS), and ion chromatography (IC) to measure calcium and phosphate concentrations. Results coming soon!

Developing a Prosthetic Arm that is Affordable and Controlled by the Brain

We have been researching neural control of hand movements using electroencephalography to determine what information is already present that can be used to further our work and provide proper background for it.Lab-Jodis - 1 (1) We are also currently working on cleaning up and analyzing the data taken last summer.

Subject1_071514_Ch1_Trial1This is an image of the EEG readings that are being analyzed. This data will be used in the article we are currently working on to be published in the near future.

This is a picture of Dr. Jodi Prosise and Mr. Milton on a recent trip to Brazil. 3

She and some engineering students gave him the new arm that she and the students designed for him.

This is the the reason this research and project is so important!

Sand and Water (but no beach?!)

Dr. Stonedahl’s group, aka “Team Caleb” is investigating the flow of water through a grid of sands. They checked in with this report:

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Caleb and Caleb, also known as “Team Caleb!”

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The hopefully finished Ant-farm Apparatus

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adding sand to permeameter

We put together a constant head permeameter to measure the permeability of sands, so that we can select two good sands to use in our experiments.

We have worked with TProGS, NetLogo, and MATLAB to model what we plan to do with the apparatus. We are progressing on integrating the codes and getting them closer to matching our system.

This group has their own blog you can follow at

And now for a little fun–it’s volleyball time for the whole USRI group!

2015 is a GO!

We are VERY excited that the SAU Undergraduate Summer Research Institute is in its 5th year! This year we have 26 students, and eight faculty participating. Here are the students (minus two who are still in Brazil with the engineering group):USRI 2015 student collage

And this year’s projects are VERY cool:

Dr. Joshua Stratton, Chemistry: The students will work in small groups to propose and carry out a research project of their own choice on the atomic absorption spectrometer available in the Chemistry Department.  This instrument is designed to measure metal levels (iron, calcium, cadmium, lead, etc.) in various sources including food, consumer products, and water. Previous projects have included iron or cadmium in chocolate, lead in tap water, and calcium in green beans or orange juice.

Dr. Hunhui Oh, Social Work: Students will be introduced to an opportunity to develop knowledge on mixed-method research analysis (a combination of qualitative and quantitative research methodology) via a series of in-class lectures, surveys and interviews with older adults in the community which is the instructor’s new research project with focus on older people’s life stories, wisdom, and well-being in rural settings. Students will learn how to collect, modify, and analyze survey and interview data correctly by using qualitative data analysis software (i.e., MAXQDA) and quantitative software (i.e., SPSS). To meet this end, students will (1) participate in in-class lectures on the key fundamental skills of research methods mentioned above during the first week, (2) conduct one-on-one interviews and surveys (which will be done simultaneously during each interview) and codings of the interview transcripts and surveys during the following two weeks under instructor’s supervision, (3) and data analysis and presentation during the second three weeks. At the end of the project, students will gain skills and confidence in both qualitative and quantitative data collection and analysis which should play a significant role in the informed decisions on the topics and approaches of their future research projects.

Dr. Jodi Prosise, Engineering: Students will be involved with developing a simple, affordable, neural-controlled upper limb prosthetic by developing a hand model for motion analysis, designing an experiment for EEG data-collection, analyzing data collected from monkeys, and re-developing current open-source models of prosthetics.

Dr. Susa Stonedahl, Physics & Engineering: Students will be conducting an experiment designed to investigate the flow of water through heterogeneous sediments.  They will collect data, analyze the data, and simulate the system using a variety of computer programs.  This is a multi-disciplinary project, which would be well suited to students from a variety of disciplines.  Engineering, chemistry, computer science, and math students are particularly encouraged to apply.

Dr. Grant Tietjen, Criminal Justice & Sociology: Are you interested in peering into the scientific sphere of severe, violent, and heinous criminal actions and the people who commit such acts? Psychopathic and sociopathic individuals. How are these two concepts different? What motivates certain members of society to commit such actions? Is it socially motivated? Is it genetically/biologically motivated? Is it environmentally motivated? This research project will examine some of the most high profile, sensationalized, and least understood types of criminal behavior, and the people who perpetrated such acts in an attempt to determine if a typology of sociopathic and psychopathic explanations for heinous criminal behavior can be established.

Dr. Katie Trujillo, Psychology: This study focuses on the impact of therapy dogs on people’s stress levels in hospital waiting room environments. Students will measure the stress of individuals before and after interacting with a therapy dog using rating scales and tools designed to gather physiological data.

We’ll be giving you updates from time to time, so check in often!


Wrapping it up

This past Friday, 21 undergraduate students wrapped up six weeks of reading, measuring, interpreting, strategizing, observing, building, calibrating, and learning to think like scholars. They shared their conclusions with an audience of faculty, staff, special guests, and students. Below are a few pictures from the presentations. They delivered very professional presentations and helped the audience understand ideas that were quite complex. Congratulations to this year’s group, and we hope some of you will return next summer!

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A Breakdown is in the Works

To start off the research institute, I (Ty Balduf) was to spend the first few weeks finding related research to my topic of polystyrene photodegradation in the presence of a sensitizer. This research was meant to assist me in developing my proposal, which is a full description of the chemistry involved in the project, the potential applications, and the intended methodology. I came across a lot of useful articles and ideas for how I could develop my research.

One of the early problems I encountered in piecing together a method was how to best irradiate the samples. There was the option of just leaving them in the windowsill and allowing the sunlight to be my UV source, but this could have led to inconsistent results due to the varying amounts of light the samples would get. Thankfully, I was directed by Dr. Gierlus to an article that offered a convenient, albeit unusual, method for irradiating samples. The article demonstrated that one could get consistent photoreactions by using a UV light nail dryer as the light source.

UV irradiation of polystyrene via a commercial gel nail "dryer"

UV irradiation of polystyrene via a commercial gel nail “dryer”

Now that I have preliminary proposal ready, I’ve begun testing to see if my procedure will really work or if some further modifications have to be made. As of right now, my current methodology involves dissolving polystyrene in dichloromethane (DCM), a volatile substance which should evaporate on a flat surface leaving only a thin film of polystyrene. A thin film is needed so I can examine the sample using ATR/FTIR (Attenuated Total Reflectance/Fourier Transform Infrared) spectroscopy. Keeping the description relatively basic, this involves placing a sample on a reflective crystal and bouncing infrared light between it and a mirror until it reaches a detector. The detector can measure how much light of different frequencies the sample absorbed. These wavelengths of absorbed light are distinct to certain chemical groups and so allow one to identify types of chemicals present. For my experiment, there are two particular frequencies I’m looking at. If the samples absorb more light at those frequencies after having been irradiated, it suggests that the polystyrene has begun to break down.

Ty analyzing the FTIR spectrum of a polystyrene/benzophenone film

Ty analyzing the FTIR spectrum of a polystyrene/benzophenone film


In the time since I’ve started testing, I’ve encountered a few issues that I’ll need to address, namely that our current ATR crystal is not designed for this type of sample. Fortunately, USRI has provided funding to purchase a new flat plate ZnSe ATR crystal that should allow for more consistent sample prep and analysis. With these tweaks to the method and the new equipment, I’m looking forward to making further progress as I continue the project during the fall semester.

Ty Balduf

In the Home Stretch

We are about to enter the last week of our summer research experience, and students have their noses to the grindstone, trying to get as much done as possible before we disperse. One valuable lesson that I think all students come away with is that research and scholarship invariably involve unexpected complications, delays, things that don’t go as planned. This is the nature of discovery. And discovery would be downright boring if everything turned out to be predictable, accessible, and uncomplicated. Another important lesson is that for every question you ask there are many more yet to be asked and answered. A lifetime of asking questions and searching for answers often yields only a small piece of the puzzle. I think it’s pretty cool to think we will never run out of questions! Off to our weekly large group lunch discussion…

-Katie Trujillo