Left to Right: Tana Villafana (Scholar), Brian Crouch (Fellow), Dalton Sycks (Fellow), William Eldridge (Fellow), Jenna Mueller (Scholar), Yuan Fang (Fellow), Derek Ho (Fellow), Lindsay McTague (Fellow), and Jong Kang Park (Scholar)
Brian Crouch (Chambers Fellow) is a first year Biomedical Engineering PhD student under the mentorship of Dr. Nimmi Ramanujam. Brian graduated magna cum laude from Southern Methodist University in 2012 with a BS in Electrical Engineering with a biomedical specialization and a BA in Chemistry. After finishing his undergraduate career, he began his graduate career at Southern Methodist University earning a MS in Electrical Engineering in 2013. During his undergraduate career he worked in the Biometrics Works Research Lab, a lab focused primarily on the innovation and improvement of iris recognition algorithms. Brian’s master’s thesis focused on improving iris recognition when the acquired image was of an off-axis eye, or an eye not aligned with the camera’s optical axis. By using a genetic algorithm to optimize the filters used when extracting features from off-axis irises, he was able to improve recognition to a level acceptable by current recognition algorithms. Through this research, Brian was exposed to and took an interest in the optical systems used to capture high-resolution images of the eye at varying wavelengths of light. Combining this interest in optical systems with his passion for biomedical applications, Brian has now turned his research focus to optical applications in biomedical engineering working in the Tissue Optical Spectroscopy (TOpS) lab. His research will focus on identifying biological markers in precancerous cells that indicate the onset of oncogenesis. These biological markers can then be used to aid in early cancer detection and treatment.
William Eldridge (Chambers Fellow) is a PhD student working under Dr. Adam Wax in the Department of Biomedical Engineering. He graduated from UNC –Chapel Hill in 2010 with a BS in Applied Science – Biomedical Engineering, where he developed a behavioral testing apparatus for assessing the viability of an auditory prosthesis in the inferior colliculus, a portion of the brain in the auditory signal pathway. Following his bachelors, he earned his MS in Biomedical Engineering from Duke University, working with Dr. Wax to develop anti-EGFR conjugated plasmonic gold nanoparticles for the delineation of head and neck tumor margins. Upon completion of his degree, he was awarded the BME Excellence in Master's Studies Award. Following graduation, Will worked for Becton Dickinson Technologies in RTP and Ingersoll Rand. His current graduate research interests include building a dark-field fiber optic probe for the delineation of brain cancer margins in vivo using antibody conjugated gold nanorods. These nanoparticles, which have characteristic scattering spectra due to their composition and geometry, are functionalized with antibodies that target epidermal growth factor receptor (EGFR), an overexpressed receptor found on many head and neck tumors. Furthermore, Will is assisting in efforts to create a wide-field lock-in photothermal holography system for the detection of antibody conjugated nanoparticles bound to living cells. As plasmonic gold nanoparticles are illuminated by light near their resonant wavelength, the metal nanostructure becomes heated, causing local variations in the refractive index surrounding the nanoparticle, leading to a strong phase-induced signal. He hopes to translate the skillsets gained while building these devices into creating neuro-endoscopes for molecular-imaging, diagnostic, and photo-therapeutic purposes.
Yuan Fang (Chambers Fellow) is a first year PhD graduate student in Professor Qing H. Liu’s group from the department of Electrical and Computer Engineering at Duke University since August 2013. Before receiving the Bachelor degree from Zhejiang University in Hangzhou, China, he focused on using numerical method to study the interconnect behaviors of nanocarbon materials and made an oral presentation on Asia-Pacific Symposium on Electromagnetic Compatibility (APEMC). Yuan’s current interests are computational electromagnetics, advanced electromagnetic theory and application in electromagnetic imaging. The technology can be used for detecting the underground layers, locating petroleum, and risky surgery for searching necrotic area. Now he is working on using efficient electromagnetic algorithm to accurately simulate the electromagnetic devices and study the electromagnetic field behavior in inhomogeneous multi-layered media. The research is targeted to develop a practical device model for underground detection. Yuan is also working on integrated optics by simulating the behavior of Extremely Ultra Violet (EUV) on optical devices.
Derek Ho (Chambers Fellow) is a first year biomedical engineering PhD student at Duke under the mentorship of Dr. Adam Wax. He received his B. Sc. in biomedical engineering from the University of Texas at Austin in 2013. As an undergraduate, his research interests focused on biomedical optics, and he worked on a project designing a combined optical coherence tomography (OCT) and two photon luminescence imaging system for the detection of thin cap fibroatheroma. Macrophage localization in atherosclerotic plaques is influential in the development and rupture of thin-cap fibroatheromas. OCT can be used to image the surface profile and plaque formations in blood vessels while two photon luminescence can be used to detect gold nanoparticles endocytosed by macrophages within the plaques. Thus, a combined system has the potential to simultaneously determine macrophage localization and image plaque structures in the coronary artery to distinguish atherosclerotic plaques that are more prone to rupture. His current research at Duke involves designing an angle-resolved low coherence interferometry (a/LCI) probe that will be used to determine nuclear size distribution and density in cervical tissue. Nuclear morphology can be used to identify dysplastic tissues, which makes a/LCI a promising technique for the early detection of pre-cancerous growths in the cervix.
Lindsay McTague (Chambers Fellow) is a first year PhD student in the Electrical and Computer Engineering department. She received her BS in Physics, with minors in both mathematics and computer science, from Siena College in Loudonville, NY. Her student research at Siena was comprised of the design of the optical lightning detector for FireStation, a NASA GSFC mission that was mounted on the International Space Station in August 2013, as well as the mechanical integration of Firefly, a NSF CubeSat set to launch in November 2013. The primary science objective of both these missions is to determine the relationship between terrestrial gamma-ray flashes (TGFs) and lightning on one, integrated platform, which will virtually eliminate the timing discrepancies that have occurred in past research. She is currently a member of Dr. Steven Cummer’s research group, with whom she plans on broadening and enhancing her curiosity and passion for research in lightning and TGFs.
Dalton Sycks (Chambers Fellow) is a first year PhD student in Duke’s Mechanical Engineering and Materials Science Department. Dalton received his undergraduate education at the University of Arizona, where he obtained dual degrees in Materials Science and Mathematics. During Dalton’s time in Arizona, he concentrated on biomaterial characterization and antimicrobial properties, as well as spending a summer at Mayo Clinic histologically analyzing aneurysm treatment models. Currently, however, Dalton is funded by an NSF GRFP to focus on the intersection of rapid prototyping and the creation of tough hydrogels capable of serving as cellular matrices. An important application of Dalton’s work is in regenerative medicine, particularly concerning articulating cartilage (found in places like the knee joint) where tough, durable materials are required. His group aims to be the first group to develop not only a tough, cell-encapsulatable hydrogel, but one that can be fabricated by 3D printing for enhanced personalization between patients.
Jenna Mueller (Chambers Scholar) is a PhD student in Dr. Nimmi Ramanujam’s Tissue Optical Spectroscopy Lab in the department of Biomedical Engineering. Jenna received a B.S. degree in Bioengineering from Rice University in 2009 with a minor in Global Health Technologies. Her primary research involves how the combination of exogenous contrast agents, structured illumination fluorescence microscopy, and appropriate image analysis algorithms can be used to detect and diagnosis cancer at the point of care.
Specifically, histopathology is the clinical standard for tissue diagnosis. When diagnosing cancer, pathologists look for changes in tissue morphology including changes in nuclei and surrounding tissue. However, histopathology has several limitations including that it requires tissue processing, which can take 30 minutes or more, and requires a highly trained pathologist to diagnose the tissue. Taken together, it is difficult to diagnose tissue at the point of care using histopathology.
Optical microscopy is a powerful technique to obtain high resolution images of tissue morphology in real-time, without the need for fixing, sectioning, and staining. While optical microscopy is well suited to enable visualization of tissue morphology at the point of care, robust methods for segmentation and quantitative analysis are essential to enable automated diagnosis. Thus, the goal of her work is to maintain high resolution imaging of tissue morphology through employing structured illumination fluorescence microscopy and vital fluorescent stains but to also develop a quantitative strategy to segment and quantify tissue features, such as nuclei and the surrounding tissue, which will enable automated diagnosis of thick tissues. Specifically, she is employing an image processing method called sparse decomposition that can differentiate nuclei from background tissue heterogeneity with minimal user manipulation. Ultimately, her work will yield an optimized system that is capable of automated segmentation and quantification of high resolution thick tissue images.
Jong Kang Park (Chambers Scholar) received his B. Sc. (2004) and M. Sc. (2008) degrees in chemistry from Yonsei University, Korea. His master degree thesis, “Studies on dye-sensitized solar cells utilizing modified porphyrins and Mӧbius aromaticity triggered by metalation in N-fused pentaphyrin”, was awarded the Master Thesis Award in Natural Science by Yonsei Univeristy. After completing his master degree, Jong continued to work on electron transfer dynamics between porphyrin and fullerene at the Natural Science Research Institute of Yonsei University from 2008 to 2009 as a research assistant. He is currently working toward his Ph.D in the areas of nonlinear optics and multiphoton imaging under the advisement of Dr. Therien and Dr. Warren at Duke University. Jong’s current works include designing multiporphyrin-incorporated biocompatible polymersomes with >107 GM (Gӧppert-Mayer) per nano-object and characterizing two-photon absorption (TPA) cross-sections of highly -conjugated multiporphyrins in polymersomes in order to render novel two-photon imaging agents to achieve brighter, deeper and safer multiphoton imaging in biological tissues. In addition he is investigating the nonlinear absorption and phase contrast of carbon-based nanomaterials (graphene and carbon nanotubes) as possible formats for in vivo nonlinear imaging applications and novel optical devices.
Tana Villafana (Chambers Scholar) is a Ph.D student in the chemistry department of Duke University working in the lab of Dr. Warren Warren. She is an artist and a scientist who by some luck stumbled upon the exciting world where art and science come together. The study of our cultural heritage can unlock mysteries surrounding long forgotten cultures and past histories as well as provide conservators with means to preserve that culture. There are a plethora of analytical techniques currently available to conservation scientists for the study of artist's materials, however information on an artist's working methods is contained only within the 3d structure of the artwork. For example, an x-ray fluorescence spectrum of a particular spot on a painting would show elemental information about all the pigments contained within that spot, but not where the pigments are in the painting. The presence of lead could indicate that lead white has been mixed with a pigment or that lead white was used in preparation of the ground. In general, current methods for material investigation do not provide quantative depth information and the construction and composition of layers in a painting has to be studied by the physical removal from a small sample from the artwork. The Warren lab has long worked on imaging in highly scattering biological samples and Tana has recently applied their ultrafast nonlinear imaging technique to pigments and paintings. Optical pump-probe microscopy can provide high resolution 3d images in highly scattering pigment samples and provide chemical contrast specific to many pigments. Tana has been able to create virtual cross-sections in several mock-up paintings, distinguishing between multiple pigments as well as highlight mixed versus layered samples. She has also imaged an intact 14th century painting, The Crucifixion by Puccio Cappana, with no visible damage to the painting. Currently she is working on developing a spectral pump-probe database for pigments available during the early Italian renaissance, which she will apply to several Kress foundation paintings that are in the permanent collection of the North Carolina Museum of Art. Using pump-probe microscopy in conjunction with traditional conservation science techniques, she aims to reach historically relevant conclusions about these paintings. Tana is also a conservation intern at the NCMA as well as a Mellon Fellow at the National Gallery of Art studying traditional conservation and conservation science techniques.