OUR WORK

Recovery of Fine Details for Fast Imaging Knee Pathologies

By Jasina Yu

Portrait of Jasina Yu

 

Knee diseases or injuries are very common in the United States. For example, more than 14 million Americans suffer from knee osteoarthritis. Magnetic resonance imaging (MRI), as an interdisciplinary field of computer science, mathematics, engineering, and MR physics, provides an accurate noninvasive assessment of knee pathology. The soft tissue structures (such as menisci, ligaments, and cartilage) and bone marrow of the knee can be visualized for diagnosis and prognosis. However, an MRI scan generally needs 45-90 minutes. As a freshman, I am interested in computer science, mathematics, and physics. MRI integrates those fields, and it is a great research topic to achieve my study goals.

The objective of the project is to advance our understanding of MRI by keeping fine details of knee images. Knee pathologies are accurately visualized without sacrificing imaging speed. The fundamental understanding of the feature representation, extraction, and selection in the artificial intelligence (AI)-based reconstruction process will benefit the knee pathology features’ recovery from highly undersampled data. Detailed information lost in the reconstruction process was studied. This project has helped initiate my research activities at UMD and I hope to advance my career as a researcher and innovator in biomedical imaging investigation.

 

 

Based on the preliminary research using the fastMRI dataset [1], our AI-based technique (as shown in the 4^th column of the figure above) can recover more details than the other two methods shown in the 2^nd and 3^rd columns of the figure. The reference knee image is shown in the 1^st column of the figure. Our AI method has closer pathological details to the reference knee image because the other two methods have degraded image quality.

 

Reference

[1]. Knoll F, et. al. fastMRI: a publicly available raw k-space and DICOM dataset of knee images for accelerated MR image reconstruction using machine learning. Radiol Artif Intell. 2020;2(1): e190007.

Cell Viability of Novel Wound Healing Hydrogels

By Abid Neron

 

Introduction

Over the summer and my fall semester, I was culturing cells. I started off completely clueless but slowly I started learning and gaining a better understanding of the ins and outs of cell culture. I should start off by explaining what cell culture actually is. Basically, it’s growing a certain cell outside of its normal environment, in a lab. Cell culture is used to study these cells’ growth patterns and how to change their rate of growth. There are multiple cell lines/types, such as skin cells, kidney cells, cancer cells, and much more. I was mostly culturing HEK293 cells which are mammalian kidney cells. I also cultured A375 cells as well, these are a skin cancer cell line. I started off doing cell culture by just following a list of steps telling me what to do. I didn’t understand what I was doing, though. After some research and passaging my cells multiple times, I started to get an understanding of what cell culture is and the steps started making sense. Finally, after perfecting my technique, I wanted to start research using them. I talked to Dr. Tracie Ferreira, and she tasked me with creating a protocol to test cell growth on certain substances. This protocol would be used by the seniors on their final projects. I was introduced to the seniors and their projects and collaborated with them using my knowledge of cell culture.

Abid Neron passaging his cells inside a biosafety cabinet

 

Methods

Creating a standard protocol to test cell growth (Also known as cell viability) took a lot of research and multiple failed experiments but with each failed experiment I went back to the drawing board and tweaked some steps until I finally found the best method to test cell viability.

My cell viability test uses a substance called Resazurin which is a special dye that changes color depending on cell activity. Cells produce ATP. Resazurin changes color based on the amount of ATP produced. As cell number increases, so does the production of ATP. Further, Resazurin doesn’t affect cells’ growth and doesn’t damage them unlike other cell viability tests. Using a Spectrometer, I can analyze the change in color for each test. The larger the value the more cells were growing. After testing my protocol on students’ substances called Hydrogels, the test offered good results and could be replicated multiple times to get more accurate results if needed. Seniors are currently using the protocol I created to test cell viability on their Hydrogels.

I had an issue with bacteria growing on the hydrogels which would mess up the test, so after multiple experiments, I found the best way to sterilize the hydrogels and keep bacteria away from the cells by using different plates everyday to get more accurate results.

Cell Viability Test

(Notice how the bottom right well is a brighter color, that means that the cells are growing faster!)

 

Results

I tested my protocol on multiple hydrogels and compared their growth with cells growing under optimal conditions:

A hydrogel’s cell viability over 5 days

 

 

Discussion

My research is still ongoing and I’m constantly furthering my knowledge of cell culture and perfecting my technique. Cell culturing has become an almost therapeutic process for me. While there’s a lot to learn, it’s always nice to apply what I’m learning about. Researching cell culture is an incredible experience that I truly loved and sharing my experience with other students and teaching them cell culture and seeing their awe when they see cells growing is always rewarding. I wouldn’t have had this experience if it weren’t for Dr. Trace Ferreira. She taught me everything I know about cell culture and is always there to bounce ideas with. Going forward, I will test more hydrogels and hopefully teach more students how to apply my cell viability test in their own research.

Characterizing the Friction Induced Triboelectric Effect of Polymers

By Viktoriya Balabanova

Portrait of Viktoriya at work in the lab

Introduction

 

Triboelectric generators (TEGs) use the triboelectric effect between two layers of materials to convert mechanical movement (e.g. sliding) into electric power (Figure 1)^1–4. These generators were developed in recent years and provide the most effective approach to harvest low-frequency mechanical energy for distributed energy applications. Up to now, almost all reported TEGs are designed to work in a charge-saturation state, meaning that more than enough force is used to guarantee maximum triboelectrification of materials in the device, which results in the waste of mechanical energy and low energy conversion efficiency.

Unlike previous studies, our research group hypothesizes that the TEGs will achieve maximum efficiency if they work under the minimum friction force that induces the saturation of triboelectric charges. This hypothesis cannot be tested until we know the friction force-triboelectric charge correlations in materials. This study aims to characterize such correlations in selected polymers. These polymers are the key materials that make the TEGs versatile, efficient, and cost-effective. The results of this project are significant because they will (1) provide preliminary data to test our significant hypothesis about TEGs, (2) help us gain new insights into previously unknown charge transfer mechanisms between two sliding surfaces.

Methods

We designed and built the setup shown in Figure 2, in order to measure the dynamic friction force and triboelectric charge induction simultaneously in a working sliding-mode triboelectric generator (SM-TEG). The whole setup consists of three major parts. Part 1 is a typical SM-TEG, consisted of two acrylic plates, on which adhesive spray is used to first attach stainless steel electrodes and then bind polymer sheets on top of them. Nylon film was used for the top plate  (1×1 inch), and Polytetrafluoroethylene film (PTFE, 1×3 inch ) for the bottom. Part 2 of the setup consists of ATI-Nano17/IP68 six-axis force sensor firmly mounted and suspended from a frame. The top plate of the SM-TEG is attached to a specifically designed and 3-D printed holder, which is connected to the bottom of the force sensor. This second part of the setup remains fixed throughout the whole time data is being collected. In Part 3, a control mechanism is assembled for fine tuning of the normal force and the mechanical energy we put in the system. A very sensitive Newport M-270 Lab Jack is used to adjust the distance between the TEG’s plates, thus increasing or reducing it, allows us to control the normal force applied. For this part we hypothesize that the critical friction force that makes the system saturate can be very susceptible to changes, thus the precision adjustment of the normal force is required. On top of the lab jack a shaker plate PI C-891 is mounted and used to control the sliding mode of the TEG’s bottom plate, including amplitude, frequency and velocity. Another special holder for that plate was designed, 3-D printed and attached on top of the shaker. Lastly, the TEG’s electrodes are connected (open circuit) to a Keithley 6514 electrometer to read out the voltage/current induced by the triboelectric charges.

 

Results

 

After the setup was built and calibrated, we initialized some preliminary tests to determine if the data from the force sensor and the electrometer was consistent with the behavior we expected to see. In this process we had to make micro adjustments of the setup, since we needed all parts of the TEG to be aligned and leveled. It was determined that we were ready to begin collecting data and we took several cycles of data sets for various initial forces. The obtained data was further analyzed and produced the results shown in Table 1, then it was plotted to create Figures 3 and 4.

 

 

 

 

Discussion

This summer research project aimed to characterize the correlation between friction force and triboelectric charge for selected polymers in pre-saturation states. The final results we obtained confirmed the behavior we expected to see. In Figure 3 the averages of the friction force and the applied normal force were analyzed and from the plot we can observe that the friction coefficient between the two polymers used in the TEG has a linear behavior. In Figure 4, the root-mean-squared voltage vs the normal force were examined. The charge was expected to increase with the applied force, until it reaches a saturation point under a critical force. This figure shows that after a certain threshold point, the increase of the normal force applied in the system does not increase the induced voltage. In other words, the TEG has reached a saturated state and even if we put more mechanical energy into it, it does not improve the overall performance of the TEG, resulting in low energy conversion efficiency.

This preliminary data is very important for us since it sets a clear direction for our future work. In the next year we are going to repeat the experiment and try to understand why this behavior happens, how the charge increases with force and how the critical force is affected by material properties. We are hoping to be able to create a model that will help improving the overall efficiency of TEGs, since they are a cost effective, easily manufactured, alternative source of green energy. I would like to thank Ross Jacques for his help on my project, and Dr. Caiwei Shen for his guidance and support, throughout the whole process, without whom this would not be possible!

 

 

References:

1. Wang, Z. L. Triboelectric nanogenerators as new energy technology and self-powered sensors – Principles, problems and perspectives. Faraday Discuss. 176, 447–458 (2014). DOI:10.1039/C4FD00159A
2. Xu, G., Li, X., Xia, X., Fu, J., Ding, W. & Zi, Y. On the force and energy conversion in triboelectric nanogenerators. Nano Energy 59, 154–161 (2019). DOI:10.1016/j.nanoen.2019.02.035
3. Zhang, J., Darwish, N., Coote, M. L. & Ciampi, S. Static Electrification of Plastics under Friction: The Position of Engineering-Grade Polyethylene Terephthalate in the Triboelectric Series. Adv. Eng. Mater. 22, 1–5 (2020). DOI:10.1002/adem.201901201
4. Rodrigues, C., Nunes, D., Clemente, D., Mathias, N., Correia, J. M., Rosa-Santos, P., Taveira-Pinto, F., Morais, T., Pereira, A. & Ventura, J. Emerging triboelectric nanogenerators for ocean wave energy harvesting: State of the art and future perspectives. Energy Environ. Sci. 13, 2657–2683 (2020). DOI:10.1039/d0ee01258k
5. Zou, H., Guo, L., Xue, H., Zhang, Y., Shen, X., Liu, X., Wang, P., He, X., Dai, G., Jiang, P., Zheng, H., Zhang, B., Xu, C. & Wang, Z. L. Quantifying and understanding the triboelectric series of inorganic non-metallic materials. Nat. Commun. 11, 1–7 (2020). DOI:10.1038/s41467-020-15926-1

 

 

Development of a Thermoplastic Polymer Electrolyte-based Structural Supercapacitor

By Payton Parker

 

Portrait of Payton Parker 

Introduction

Through the continually evolving world of energy usage, new ways to store energy are becoming increasingly important. For instance, in space technology, finding new ways to store energy in lighter and smaller packages is highly desirable. If weight can be reduced and the amount of stored power can be increased, the space mission durations can be lengthened significantly. To do so, devices called structural supercapacitors were built^1–4. These devices can store electrical energy while being able to support a load. These two properties allow components which originally would be used solely for structural support to also have energy storage capabilities (Figure 1 ⁵). Previous attempts at creating structural supercapacitors use an electrolyte matrix imbedded with carbon fibers functioning as both reinforcement and electrodes. The electrolyte matrix consisted of a resin mixed with ionic liquid. This mixture creates what is called a bi-continuous electrolyte. This complete separation in the electrolyte substantially limits the electrochemical and mechanical performance of the supercapacitor device^6–8.

Dr. Caiwei Shen‘s research group has recently developed a new polymer electrolyte to use in the structural supercapacitor that has much better electrical performance and mechanical properties⁹.  The key feature of this electrolyte is that it is a thermoplastic polymer-based single-phase electrolyte made using melt processing which has never been done before. This melt processing allows for increased ion transport and higher strength of the electrolyte matrix and potentially better performance of the structural supercapacitor devices.

In this project, we are proposing using this same polymer electrolyte in conjunction with carbon fiber fabric to construct new structural supercapacitor devices. The goal is to further improve the electrical and mechanical performance of the supercapacitor. To do this, we will (1) develop a new method for the manufacturing of the devices, and (2) optimize the composition of the electrolyte matrix.

 

Methods

• • Injection Molding Operation

An A&B Plastics AB-100 injection molder was used for all injection molded samples. This machine uses a pneumatic ram to force the melted material into the mold and must be connected to a compressor. To complete a “shot” (filling the cavity of the mold with molten plastic), the desired temperature of the chamber was set using the PID interface and the pneumatic ram pressure was adjusted using the built-in pressure regulator. At this point, a preheated mold was aligned under injector nozzle. Once the chamber temperature reached its target value, the ram was actuated using a lever filling the mold. After injection, the mold was removed and set aside for cooling. The part was then removed from the mold after a set amount of time.

• DSC Sample Preparation

Sample preparation for differential scanning calorimetry (DSC) was done in an M-Braun Uni-Lab Pro SP glove box. These samples were around 10 mg each and were tested using a TA Instruments DSC machine.

Results

• • Optimized Injection Molding Procedure

The goal in optimizing the injection molding procedure was to find the smallest sample thickness achievable. This is important due to relation between electrolyte thickness and capacitance. The thinner the sample, the thinner the final thickness of the full device, which in turn improves capacitive behavior. The mold shown in figure 1 was designed and machined for this purpose. It features an adjustable insert that can be shimmed to change the depth of the mold cavity from 0.040” to 0.000”. The mold can also be disassembled quickly for cleaning in-between material compositions. 6061 aluminum was chosen as the primary material due to its high thermal conductivity and machinability, however the insert portion was machined from stainless steel. This was done to reduce the chance of the insert becoming seized in place.

Insert mold design

Using this adjustable mold, a set of experiments was designed to determine the best injection parameters for polyethylene terephthalate (PET). PET was chosen for these tests as it was the preferred material used for the matrix portion of the polymer electrolyte. Using the typical design of experiments layout made for multifunctional optimization, an initial set of parameters were established and used a basis for testing. Four separate tests were then done, varying each parameter one at a time. The characteristics of each result were carefully noted on for analysis at the end of each test set. In the following tables, each row highlighted in green represents the best result for the given experimental set. Characteristics such as clarity and ease of molding were the main forms evaluation.

From this procedure, it was determined that the best parameters for PET were the following: mold temperature of 160°C, barrel temperature of 270°C, injection pressure of 60 psi, and a minimum cavity depth of 0.020”. These parameters resulted in the most consistent, clear samples.

 

• DSC Results

Differential scanning calorimetry was used to characterize two different polymer electrolyte materials. The first of which was PET+20%LiTSFI shown in figure 2. From the figure, it can be seen that the melting point is located around 234°C. The second was PLA+20%LiTSFI shown in the following figure.

Discussion

Throughout this research project, many impactful discoveries were made. Most importantly a basis for injecting solid polymer electrolyte samples was established. Now the only step needed for injecting different compositions of electrolytes (changing the total lithium salt to polymer matrix ratio) was a DSC test to find the melting point of the specific composition. The other parameters could then be adjusted based on this temperature. On top of this, the DSC tests revealed that the PLA based electrolyte has a more definite glass transition point, around 50°C. This means even in a mostly solid phase, the PLA+20%LiTSFI begins to flow at low temperatures. This characteristic may be instrumental when attempting to impregnate weaved carbon fibers in future work.

It was lastly discovered that humidity plays a major role in the injection molding process. The ambient environment where the injection molding was done tended to have high humidity levels between 50-70%. It is well known that water content can significantly impact injection molding, so every precaution was taken including drying the material before injection, sealing the injection molding barrel when not in use, and preheating the barrel before injection. Unfortunately, these attempts only had a small impact on the results. Many of the samples were still dark in color due to water that was absorbed by the injection material. For this reason, a senior design team was sponsored in the mechanical engineering department to solve this humidity control issue.

 

References

1. Xu, Y., Lu, W., Xu, G. & Chou, T. W. Structural supercapacitor composites: A review. Compos. Sci. Technol. 204, 108636 (2021). DOI:10.1016/j.compscitech.2020.108636
2. Snyder, J. F., Gienger, E. B. & Wetzel, E. D. Performance metrics for structural composites with electrochemical multifunctionality. J. Compos. Mater. 49, 1835–1848 (2015). DOI:10.1177/0021998314568167
3. Reece, R., Lekakou, C. & Smith, P. A. A structural supercapacitor based on activated carbon fabric and a solid electrolyte. Mater. Sci. Technol. (United Kingdom) 35, 368–375 (2019). DOI:10.1080/02670836.2018.1560536
4. Shirshova, N., Qian, H., Houllé, M., Steinke, J. H. G. G., Kucernak, A. R. J. J., Fontana, Q. P. V. V, Greenhalgh, E. S., Bismarck, A. & Shaffer, M. S. P. P. Multifunctional structural energy storage composite supercapacitors. Faraday Discuss. 172, 81–103 (2014). DOI:10.1039/c4fd00055b
5. Structural supercapacitor illustration. https://scitechdaily.com/big-breakthrough-for-massless-energy-storage-structural-battery-that-performs-10x-better-than-all-previous-versions/
6. Shirshova, N., Bismarck, A., Carreyette, S., Fontana, Q. P. V., Greenhalgh, E. S., Jacobsson, P., Johansson, P., Marczewski, M. J., Kalinka, G., Kucernak, A. R. J., Scheers, J., Shaffer, M. S. P., Steinke, J. H. G. & Wienrich, M. Structural supercapacitor electrolytes based on bicontinuous ionic liquid-epoxy resin systems. J. Mater. Chem. A 1, 15300–15309 (2013). DOI:10.1039/c3ta13163g
7. Tu, V., Asp, L. E., Shirshova, N., Larsson, F., Runesson, K. & Jänicke, R. Performance of bicontinuous structural electrolytes. Multifunct. Mater. 3, 025001 (2020). DOI:10.1088/2399-7532/ab8d9b
8. Greenhalgh, E. S., Ankersen, J., Asp, L. E., Bismarck, A., Fontana, Q., Houlle, M., Kalinka, G., Kucernak, A., Mistry, M., Nguyen, S., Qian, H., Shaffer, M., Shirshova, N., Steinke, J. & Wienrich, M. Mechanical, electrical and microstructural characterisation of multifunctional structural power composites. J. Compos. Mater. 49, 1823–1834 (2015). DOI:10.1177/0021998314554125
9. Joyal, N., Chang, Y.-C., Shonar, M., Chalivendra, V. & Shen, C. Solid polymer electrolytes with hydrates for structural supercapacitors. J. Energy Storage Accepted (2022).
10. Anjum, N., Grota, M., Li, D. & Shen, C. Laminate composite-based highly durable and flexible supercapacitors for wearable energy storage. J. Energy Storage 29, 101460 (2020). DOI:10.1016/j.est.2020.101460

 

 

The Influence of Lethality on the Magnitude of Prey Response to Predation Risk 

By Haleigh Nogueira 

 

This past summer I worked on a project to examine the effect of predator lethality on prey response using a rocky intertidal system. I carried out this experiment at UMass Dartmouth’s School for Marine Science & Technology (SMAST) and collected the animals from nearby sites. The summer research award from the Office of Undergraduate Research (OUR) allowed me to obtain all the needed supplies for my project and ensured I was able to solely focus on my work.

Portrait of Haleigh Nogueira at work in Buzzards Bay

 

Introduction

Predators can influence prey via both consumptive, i.e., killing, and non-consumptive predation risk effects (Sih et al. 1985; Peacor et al. 2020). Predation risk effects can alter prey behavior, physiology and morphology, which can scale up to alter individual fitness. These prey risk-responses are dependent upon the environment or context in which the predator-prey interaction occur (Schmitz 2017; Sheriff et al. 2020b), e.g., refuge availability, prey state, and predator hunting mode all influence risk responses. While predator lethality, defined as the probability that an encounter with the predator proves fatal for prey (Cooper and Frederick 2010), has been theorized to alter prey risk responses (Brown 1999; Cooper and Frederick 2010) there is little evidence to support this assumption. In marine systems the idea of predator lethality driving prey responses to predation risk is particularly of interest given that predator-prey relationships and predator identity is largely influence by individual body size; i.e., an individual’s body size relative to another dictates whether that individual is predator or prey (Barnes et al. 2010). By using a rocky intertidal system, I can examine the effect of predator lethality on prey response.

Methods

To determine the lethality of predators, I first used an experimental mesocosm manipulation to measure the consumption rates of different predator species at different sizes. A single crab of each species was placed into a mesocosm with 5 snails and their consumption was measured over 24 h. Snails were separated into two size classes (and each size placed into separate mesocosms). The mesocosms were small enough to eliminate spatial refuge for the snails. The predator, and the size of the predator, with the higher rate of consumption will be considered to have greater lethality.

I tested the hypothesis that the lethality of a predator will alter the magnitude of prey risk responses. Specifically, I predicted that when exposed to the more lethal predator (expected that larger crabs are more lethal) snails will have reduced tissue and shell growth, increased shell: tissue ratio, reduced foraging, and increased refuge use. This was tested using two size classes of Hemigrapsus sanguineus and Carcinus maenas (predators tested in part 1) and two size classes of Nucella lapillus (prey); thus, I had a fully crossed design with large and small crabs and large and small snails. Animals were placed into a mesocosm with a single crab (rendered non-lethal) and snails of a single size class. The mesocosms had a tile-refuge added. Snail tissue and shell weight was measured at the start and end of experiment using the Palmer (1982) buoyancy technique that provides non-destructive estimates; foraging and refuge use of snails was measured by behavioral observations every 3 days. The experiment ran over 20 days.

Discussion

This study will be one of the first to provide empirical evidence testing the long-held assumption that predator lethality influences prey risk responses. The results of this work will provide a better understanding of and insights into predator-prey interactions and how predation risk may alter prey phenotype and scale up to alter populations and communities. At this time I do not have any results to share, but plan to spend the rest of the semester working on my data analysis. I want to thank the Office of Undergraduate Research (OUR) and the College of Arts & Sciences (CAS) for providing me with the funds to pursue this project. I also would like to thank Dr. Michael Sheriff and my lab mates for the guidance and support they have given me throughout.

 

 

References

Barnes C, Maxwell D, Reuman DC, Jennings S. (2010). Global patterns in predator-prey    size relationships reveal size dependency of trophic transfer efficiency. Ecology.        91 (1): 222 232. https://doi.org/10.1890/08-2061.1

Brown JS. (1999). Vigilance, patch use and habitat selection: Foraging under predation     risk. Evolutionary Ecology Research. 1: 49-71.

Cooper WE, Frederick WG. (2010). Predator lethality, optimal escape behavior, and         autotomy. Behavioral Ecology. 21(1): 91–96.      https://doi.org/10.1093/beheco/arp151

Palmer AR. (1982) Growth in Marine Gastropods: A Non-Destructive Technique for          Independently Measuring Shell and Body Weight. Malacologia.23(1): 63-73

Peacor SD, Barton BT, Kimbro DL, Sih A, Sheriff MJ. (2020). A framework and        standardized   terminology to facilitate the study of predation-risk effects.         Ecology. 101(12). https://doi.org/10.1002/ecy.3152

Schmitz O. (2017). Predator and prey functional traits: Understanding the adaptive          machinery driving predator-prey interactions. F1000Research. 6: 1767 https://doi.org/10.12688/f1000research.11813.1

Sheriff MJ, Orrock JL, Ferrari MCO, Karban R, Preisser EL, Sih A, Thaler JS. (2020b).            Proportional fitness loss and the timing of defensive investment: a cohesive       framework across animals and plants. Oecologia. 193(2):273–283.          https://doi.org/10.1007/s0044202004681-1

Sheriff MJ, Peacor SD, Hawlena D, Thaker M. (2020a). Non-consumptive predator effects on prey population size: A dearth of evidence. Journal of Animal Ecology. 89 (6):1302-1316. https://doi.org/10.1111/1365-2656.13213

Sih A, Crowley P, Mcpeek M, Petranka J, Strohmeier K. (1985). Predation,

Competition, and Prey Communities: A Review of Field Experiments. Annual Review Ecological Systems.16:269311. https://doi.org/10.1146/annurev.es.16.110185.001413 

 

 

­­­­Owl-inspired experimental study on flow-induced vibration suppression with aerospace applications

 

By Abdul Raffae

 

Portrait of Abdul Raffae (left) at work in Fluid-Structure Interactions Research Laboratory at UMass-Dartmouth

 

 

In today’s industries, turbulent fluctuation causes flow induced noise that has been a major contribution to noise generation of modern structures. Many aeronautical and turbine application are rapidly developing to ensure noise reduction to better understand and control the acoustic of noise and structural vibration. In my research Fluid-Structure Interactions (FSI) is used to study the deformation or oscillation (Flow-Induced Vibration) of the structure that will go through fatigue failure in long term. In this proposed work, an owl wings will be going through detailed experimental campaign to understand the source of this turbulent and find strategies to suppress the FIV in such flexible structures. Three dominant noise-attenuation factors have been identified in owl wings that includes comb-like structure, trailing-edge feathers, and the velvet-like have been identified.

 

View of the Fluid-Structure Interactions Research Laboratory at UMass-Dartmouth where Abdul conducted his research

 

 

In Fall 2021, a flexible circular cylinder with trailing-edge serration was 3D modeled using SOLIDWORKS software cased from silicone material. This was done thanks to using the re-circulating water tunnel at Professor Banafsheh Seyedaghazadeh‘s Fluid-Structure Interactions Research Laboratory at UMass-Dartmouth. Subsequently, the effects of serrations geometry, length and aspect ratio were studied using FIV response. Since then I have been working closely with the lab to find solutions to the problem. I am planning to publish the result of this research in a peer-reviewed journal. While I cannot provide more details here, I can tell you that the impact of this research is essentially to determine the noise vibration in aeronautical and micro aerial applications. I want to thank Professor Seyedaghazadeh and other colleagues at the lab for their support. The Summer OUR fund provided an opportunity to be on campus and dedicate more time to lab work. I am grateful to the OUR for this unique opportunity.

Congressman Barney Frank and his Contributions to the LGBT Community

 

By Carmen Zhao

 

I was first introduced to the OUR summer research project by my supervisor Chan Du. In 2011 Massachusetts Congressman Barney Frank donated his archives collection that documented his U.S. congressional career from 1980-2012. They are currently located in the library’s Archives and Special Collections at UMass Dartmouth and are sorted in many boxes. During the summer, I was able to spend many hours in this room sorting through Frank’s archives to help with my research. The collection is categorized into 6 series, legislative files, district files, election and legislative records, correspondence, press and public relations, and artifacts and awards. This collection is currently in the process of being digitized. During the end of summer I was assigned a supervisor in the library, Ms. Judy Farrar. With Farrar’s help I learned how to navigate the archives and special collections. At the same time, I helped with scanning old photographs associated with Barney Frank, while investigating photographic materials for my own research. After I digitized the photos I had to try to identify the dates when these photos were shot; I was also charged with the task of identifying the photographers who took them. Subsequently, I helped write labels that would go along with these photos. When working on these descriptions it was important for me to recognize some of the people’s faces in the photos who had posed with Barney. Using Barney’s archives I was able to look through the boxes and go through newspapers and articles to try to identify and match any of the unfamiliar faces from the photographs to the names that appeared in newspaper clippings.

Portrait of Carmen Zhao

 

Barney Frank was a popular congressman, but to keep his political career “safe” he kept a secret about his identity for many years. When I first started this research project I knew little about the many sides of Barney Frank’s character. I first started by watching his documentary ‘Let’s Get Frank.’ Then I read about him in books, one an autobiography and another by Stuart E. Weisberg. These materials were helpful to me as they allowed me to get a more complete picture of Frank’s life and career. While looking through the photo albums I got to see digital images from Frank’s campaigns and public appearances. While conducting the photo research I was able to put some faces to the names that were mentioned in the books. I wrote my research paper about Barney Frank’s political career as a gay man. Frank’s biggest struggle seemed to be separating his personal life with his public life. I found how keeping his sexuality a secret effected some of the choices he made and how he was able to gain people’s trust back once he came out. I studied if he had come out earlier, he could’ve effected the outcome of his 1980 congressional run or the Democratic Primary when fighting conservative candidate, Arthur Clark. Barney defeated him in the general election in a close race. The same thing happened when Frank took on former Congresswomen Margaret Heckler in 1982, the disclosure of his sexual preferences may have lost him in these elections. It was interesting to see how these career choices and the timing of them effected the outcomes of Frank’s career. Delving into the archives was helpful because I was able to find press clippings from the years mentioned in the book related to his political fallouts that supported my paper.

 

Snapshot from Carmen’s contribution to the collection. More can be found HERE

 

UMass Dartmouth Archives and Special Collections where Carmen

conducted her research through an OUR Summer Award. 

 

I found reactions from different newsletters like the Attleboro Sun, Taunton Daily Gazette, Dover-Sherborn Suburban Press, Sun Chronicle, and Arizona Republic which published  stories when Barney voluntarily came out. These pieces expressed a variety of thoughts and opinions on the situation.  It was very informative to know that Frank was not alone in this struggle. There were many people who were closeted politicians as Barney mentions some of his gay colleagues in his writings. However, the important point to highlight here is that while still silent about his sexual orientation, Barney was an advocate for LGBT. In the archives legislative files are divided into sessions of Congress and special issues. There I found his dealings with LGBT issues and I was able to find more information on these issues that occupied a good portion of Frank’s career. I plan to expand my research paper based on my work at the archives and hopefully publish it in the near future. The extended paper will focus on Frank’s early struggles that soon forced him to make the decision to come out despite the possible negative effect on his career. For this research opportunity, I am grateful to the OUR as well as to my advisor Associate Dean Chan Du and supervisor Judith Farrar.

 

 

Determining the Therapeutic Effects of VitB on Type II Diabetic Bone

By Christian Ray

 

 

Introduction

It has been hypothesized that Type 2 Diabetes Mellitus (T2DM)may be a direct cause of osteoporosis due to a decrease in bone tissue quality.^1,3 For example, one study found that T2DM was responsible for a 2-3 times increase of hip fracture risk.¹ While the presence of T2DM was initially thought to be a favorable effect on bone strength since it could increase the mineral density of the tissue, this idea was later reassessed through more detailed and rigorous analysis procedures; furthermore, it has been found that while the amount of bone mass and magnitude of mineral density are relatable to bone strength, the density of diabetic bone does not promote bone toughness and in fact decreases it.^3,8 These procedures, such as micro indentation and computer-generated tomography, revealed that the increase in mineral density had numerous detrimental effects on bone strength including bone remodeling inhibition, increased bone resorption, and overall poorer tissue quality.³

Portrait of Christian Ray

 

To be more specific, bone tissue quality can be deteriorated by non-enzymatic glycation (NEG), a naturally-occurring process resulting in the increase of advanced glycation end-products (AGEs).⁷ The AGEs intra- and inter-fibrillar crosslinks that form throughout the collagen fiber network, causing the matrix to have stiffer properties and thus become more susceptible to breakage; this is a significant factor since over 90% of bone tissue is comprised of collagen fibers which are directly responsible for the elasticity, strength and overall toughness of bone.^7,8,9 From a chemistry viewpoint, the NEG process is the reaction of a reducing sugar (such as ribose) and an amino group (such as lysine and hydroxylysine) from the collagen. In addition, AGE accumulation has also been known to inhibit bone resorption thus leading to a decrease in bone turnover, an important biological process for maintaining bone tissue quality.⁶ Therefore, it is possible that AGEs affect the bone’s mechanical strength by deteriorating tissue quality through the bone resorption process.⁶ Overall, the accumulation of AGEs interferes with the bone structure by degrading the tissue quality and changing its mechanical and chemical properties; furthermore, this process can be further progressed due to aging and diseases such as T2DM.^7-9

 

For this project, together with my peers and mentor Professor Lamya Karim at the Bone Biomechanics Lab at UMass Dartmouth, we aimed to test a drug that can reverse or reduce the harmful effects of AGEs in bone. We decided to utilize the properties of Vitamin B6 (also known as pyridoxamine hydrochloride) due to its ability to counteract AGE formation in bone tissue.^11,12 It is also an ideal treatment due to its natural presence in foods and food supplements, meaning that it is less likely to have harmful side effects unlike previously tested AGE inhibitors. Because of the lack of in-depth mechanical research of vitamin B6 as a treatment for bone deterioration, it is necessary to perform controlled studies on bone treated with varying doses of vitamin B6 in vitro. This will provide useful information to improve treatment for T2D patients.

 

Overall, there is still insufficient research and information regarding the processes and effects of AGEs on bone. The goal of this study is to determine the extent of VitB6 effectiveness as an AGE inhibitor as well as to find any unexpected effects due to the compound.

 

 

Methods

Specimen Collection

All bone samples were collected from the left tibia of 4 female human donors; 3 of these donors had no records of leg-related injuries or bone-affecting diseases and pharmaceuticals, while the fourth donor had Type 2 diabetes. The bone specimens were always shipped frozen with ice packs and insulating boxes and then stored at –20^oC for preservation purposes. Once received, the tibias were each cut into 6 sections using a Craftsman 10” Band Saw where 15% of the total bone was removed from each end and the remaining middle part was divided into four sections. The proximal and distal ends were wrapped in saline-soaked gauze and stored away at -20^oC for other projects. The medial halves of the lateral sections were then cut off using an IsoMet 1000 Precision Saw with a medium-coarse grit diamond blade; the medial halves were then stored in saline-filled zip lock bags and stored at –20^oC for other projects. Using the same saw, each of the lateral halves were then vertically divided into 8-10 cortical beams. Once completed, a South Bay Technology Model 900 Polisher was used to remove the trabecular bone and soft tissue from the beams and to narrow the dimensions down to 2mm x 2mm x 30mm. To maintain awareness of their orientation, the periosteal surface was marked with black ink, and the proximal and distal ends were marked with red and green ink, respectively. The finished beams were then stored in saline-filled microtubes and frozen at –20^oC in cryoboxes.

 

Microcomputed Tomography Imaging

After the beams were done being cut and polished to the correct dimensions, they were then shipped out to Beth Israel Deaconess Medical Center to be imaged via high-resolution Micro-CT to obtain measures of tissue mineral density, cortical porosity, and overall beam geometry.¹⁰ In order to preserve the tissue quality of the samples, the samples were stored in saline in microtubes and cryoboxes and then stored in Styrofoam-insulated boxes with dry-ice.

 

In Vitro Biochemical Incubations

In order to incubate 60 beams in total, the required chemicals for the various solutions were calculated beforehand, as shown in Table 1. Overall, the 60 beams were randomly divided into 5 incubation groups labeled as Control, Ribose, 50mM, 75mM, and 100mM. The Control solution consisted of all the main chemicals aside from the ribose and vitamin B, while the Ribose contained all of the main chemicals aside from vitamin B. The rest of the solutions (which also consisted of the same concentration of ribose) were labeled based on their concentration of vitamin B. The individual amounts of the chemicals in reference to each solution are shown in Table 2.

In order to be more time efficient and ensure consistency of the chemical compositions between the solutions, we mixed all of the ingredients except the ribose and Vitamin B in a 5-gallon glass container with a long, polymer-based, stirring rod. After pouring out enough of this solution into the Control beaker, we added the total amount of ribose into the container and mixed until completely dissolved; once complete, we poured it into the four remaining types of beakers. Then, various amounts of vitamin B were added and dissolved into its respective beakers.

Once the chemicals were all added into the various beakers, the pH of them were individually adjusted using 0.5N NaOH or 0.5N HCl in order to bring the pH within the range of 7.2-7.6; later on, we chose to start using tablets of NaOH due to the rapidly increasing volume from using the diluted version. After the pH was adjusted, the samples were placed in labeled cassettes and randomly put into the five solutions. The beakers were then covered with parafilm and incubated at 37^oC for 14 days, with their pH levels measured and adjusted daily. On the 14^th day, the samples were removed from the beakers, rinsed off with saline, and stored in their respective microtubes with saline and frozen at -20^oC.

Discussion

While most of the project went smoothly throughout the summer, there were some unexpected factors that hindered the projects time efficiency and perhaps other components as well. The first occurrence was when the samples were shipped out to the medical center for Micro CT imaging, where D#00 was accidentally packed and sent to them despite the samples not being complete and ready. This may have caused the samples to be exposed to warmer temperatures than desired for a longer period of time compared to the rest of the donors; however, the samples appeared to be sufficiently cold once shipped back to the lab, indicating that there should be no significant issues relating to tissue degradation.

The second occurrence was when we were adjusting the pH of the solutions during the incubation stage. Initially, we were adjusting the pH using a diluted solution of NaOH; however, the volume increased dramatically due to the drastic changes in pH during the first few days. This could potentially influence the incubation of the samples since the addition of water may have diluted the rest of the chemicals in the solution and thus possibly changing the outcome of its effectiveness.

Overall, the project is still ongoing as there are more stages required for testing and collecting data from the samples that will be conducted throughout the fall semester; this includes mechanical 3-point bending tests, micro indentation, cRPI, and fAGE measurements.

 

References

1. Karim L, Bouxsein ML. Effect of type 2 diabetes-related non-enzymatic glycation on bone biomechanical properties. Bone. 2016;82:21-27. doi:10.1016/j.bone.2015.07.028
2.  Valcourt U, Merle B, Gineyts E, Viguet-Carrin S, Delmas PD, Garnero P. Non-enzymatic glycation of bone collagen modifies osteoclastic activity and differentiation. J Biol Chem. 2007;282(8):5691-5703. doi:10.1074/jbc.M610536200
3. Wongdee K, Charoenphandhu N. Update on type 2 diabetes-related osteoporosis. World J Diabetes. 2015;6(5):673-678. doi:10.4239/wjd.v6.i5.673
4. Singh, R., Barden, A., Mori, T. et al. Advanced glycation end-products: a review. Diabetologia 44, 129–146 (2001). https://doi.org/10.1007/s001250051591
5. Karim L, Moulton J, Van Vliet M, Velie K, Robbins A, Malekipour F, Abdeen A, Ayres D, Bouxsein ML. Bone microarchitecture, biomechanical properties, and advanced glycation end-products in the proximal femur of adults with type 2 diabetes. Bone. 2018;114:32-9. Epub 2018/06/02. doi: 10.1016/j.bone.2018.05.030. PubMed PMID: 29857063; PMCID: PMC6141002.
6. Karim L, Vashishth D. Heterogeneous glycation of cancellous bone and its association with bone quality and fragility. PloS one. 2012;7(4):e35047. doi: 10.1371/journal.pone.0035047. PubMed PMID: 22514706; PMCID: PMC3325937.
7. Poundarik AA, Wu PC, Evis Z, Sroga GE, Ural A, Rubin M, Vashishth D. A direct role of collagen glycation in bone fracture. Journal of the mechanical behavior of biomedical materials. 2015;52:120-30. Epub 2015/11/05. doi: 10.1016/j.jmbbm.2015.08.012. PubMed PMID: 26530231; PMCID: PMC4651854.
8. Tang SY, Zeenath U, Vashishth D. Effects of non-enzymatic glycation on cancellous bone fragility. Bone. 2007;40(4):1144-51. doi: 10.1016/j.bone.2006.12.056. PubMed PMID: 17257914; PMCID: PMC4398019.
9. Vashishth D, Gibson GJ, Khoury JI, Schaffler MB, Kimura J, Fyhrie DP. Influence of nonenzymatic glycation on biomechanical properties of cortical bone. Bone. 2001;28(2):195-201. PubMed PMID: 11182378.
10. Research centers. BIDMC of Boston. https://www.bidmc.org/research/research-centers. Accessed September 8, 2022.
11. Voziyan PA, Khalifah RG, Thibaudeau C, Yildiz A, Jacob J, Serianni AS, Hudson BG. Modification of proteins in vitro by physiological levels of glucose: pyridoxamine inhibits conversion of Amadori intermediate to advanced glycation end-products through binding of redox metal ions. J Biol Chem. 2003 Nov 21;278(47):46616-24. doi: 10.1074/jbc.M307155200. Epub 2003 Sep 15. PMID: 12975371.
12. Abar O, Dharmar S, Tang S. The effect of aminoguanidine (AG) and pyridoxamine (PM) on ageing human cortical bone. Bone & joint research. 2018;7(1):105-10.