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Biomedical Engineering and Bioengineering Commons

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Selected Works

2013

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Articles 1 - 18 of 18

Full-Text Articles in Biomedical Engineering and Bioengineering

Systematic Genomic Identification Of Colorectal Cancer Genes Delineating Advanced From Early Clinical Stage, Patrick Flaherty Dec 2013

Systematic Genomic Identification Of Colorectal Cancer Genes Delineating Advanced From Early Clinical Stage, Patrick Flaherty

Patrick Flaherty

Background: Colorectal cancer is the third leading cause of cancer deaths in the United States. The initial assessment of colorectal cancer involves clinical staging that takes into account the extent of primary tumor invasion, determining the number of lymph nodes with metastatic cancer and the identification of metastatic sites
in other organs. Advanced clinical stage indicates metastatic cancer, either in regional lymph nodes or in distant organs. While the genomic and genetic basis of colorectal cancer has been elucidated to some degree, less is known about the identity of specific cancer genes that are associated with advanced clinical stage and …


Pre-Amplifiers For A 15-Tesla Magnetic Resonance Imager, Chin-Leong Lim, Peter Serano, Jerome L. Ackerman Nov 2013

Pre-Amplifiers For A 15-Tesla Magnetic Resonance Imager, Chin-Leong Lim, Peter Serano, Jerome L. Ackerman

Chin-Leong Lim

High-field magnetic resonance imagers (MRI) give better signal-to-noise ratio (SNR) and image contrast. However clinical MRIs are currently limited to 3 Tesla (T) magnetic field strength. To create an uncommon 15 T scanner for research use, we evaluated several low-cost, intended for wireless communication, GaAs enhancement-mode pseudomorphic high electron mobility transistors (ePHEMT) in the critical preamplifier slot. This paper reports the experimental results that were obtained at both module and system levels. When evaluated in our prototype 15 T scanner front-end’s preamplifier slot, the candidate devices’ sub 1dB noise figures enabled image SNR ~ 110 in a water phantom (test …


Toward A Gpu-Accelerated Immersed Boundary Method For Wind Forecasting Over Complex Terrain, Rey Deleon, Kyle Felzien, Inanc Senocak Sep 2013

Toward A Gpu-Accelerated Immersed Boundary Method For Wind Forecasting Over Complex Terrain, Rey Deleon, Kyle Felzien, Inanc Senocak

Inanc Senocak

A short-term wind power forecasting capability can be a valuable tool in the renewable energy industry to address load-balancing issues that arise from intermittent wind fields. Although numerical weather prediction models have been used to forecast winds, their applicability to micro-scale atmospheric boundary layer flows and ability to predict wind speeds at turbine hub height with a desired accuracy is not clear. To address this issue, we develop a multi-GPU parallel flow solver to forecast winds over complex terrain at the micro-scale, where computational domain size can range from meters to several kilometers. In the solver, we adopt the immersed …


Computational Design Optimization For Microfluidic Magnetophoresis, Brian Dennis Plouffe, Laura H. Lewis, Shashi Krishna Murthy Aug 2013

Computational Design Optimization For Microfluidic Magnetophoresis, Brian Dennis Plouffe, Laura H. Lewis, Shashi Krishna Murthy

Laura H. Lewis

Current macro- and microfluidic approaches for the isolation of mammalian cells are limited in both efficiency and purity. In order to design a robust platform for the enumeration of a target cell population, high collection efficiencies are required. Additionally, the ability to isolate pure populations with minimal biological perturbation and efficient off-chip recovery will enable subcellular analyses of these cells for applications in personalized medicine. Here, a rational design approach for a simple and efficient device that isolates target cell populations via magnetic tagging is presented. In this work, two magnetophoretic microfluidic device designs are described, with optimized dimensions and …


Development Of A Novel Handheld Device For Active Compensation Of Physiological Tremor, Abhijit Saxena Jul 2013

Development Of A Novel Handheld Device For Active Compensation Of Physiological Tremor, Abhijit Saxena

Abhijit Saxena

In microsurgery, the human hand imposes certain limitations in accurately positioning the tip of a device such as scalpel. Any errors in the motion of the hand make microsurgical procedures difficult and involuntary motions such as hand tremors can make some procedures significantly difficult to perform. This is particularly true in the case of vitreoretinal microsurgery. The most familiar source of involuntary motion is physiological tremor. Real-time compensation of tremor is, therefore, necessary to assist surgeons to precisely position and manipulate the tool-tip to accurately perform a microsurgery. In this thesis, a novel handheld device (AID) is described for compensation …


Influence Of Van Der Waals Forces On Increasing The Strength And Toughness In Dynamic Fracture Of Nanofibre Networks: A Peridynamic Approach, Florin Bobaru Ph.D. Jul 2013

Influence Of Van Der Waals Forces On Increasing The Strength And Toughness In Dynamic Fracture Of Nanofibre Networks: A Peridynamic Approach, Florin Bobaru Ph.D.

Florin Bobaru Ph.D.

The peridynamic method is used here to analyse the effect of van der Waals forces on the mechanical behaviour and strength and toughness properties of three-dimensional nanofibre networks under imposed stretch deformation. The peridynamic formulation allows for a natural inclusion of long-range forces (such as van der Waals forces) by considering all interactions as ‘long-range’. We use van der Waals interactions only between different fibres and do not need to model individual atoms. Fracture is introduced at the microstructural (peridynamic bond) level for the microelastic type bonds, while van der Waals bonds can reform at any time. We conduct statistical …


Rvd: A Command-Line Program For Ultrasensitive Rare Single Nucleotide Variant Detection Using Targeted Next-Generation Dna Resequencing, Patrick Flaherty May 2013

Rvd: A Command-Line Program For Ultrasensitive Rare Single Nucleotide Variant Detection Using Targeted Next-Generation Dna Resequencing, Patrick Flaherty

Patrick Flaherty

Background: Rare single nucleotide variants play an important role in genetic diversity and heterogeneity of specific human disease. For example, an individual clinical sample can harbor rare mutations at minor frequencies. Genetic diversity within an individual clinical sample is oftentimes reflected in rare mutations. Therefore, detecting
rare variants prior to treatment may prove to be a useful predictor for therapeutic response. Current rare variant detection algorithms using next generation DNA sequencing are limited by inherent sequencing error rate and platform availability.
Findings: Here we describe an optimized implementation of a rare variant detection algorithm called RVD for use in targeted …


Overcoming The Diffraction Limit Using Multiple Light Scattering In A Highly Disordered Medium, Youngwoon Choi, Taeseok Daniel Yang, Christopher Fang-Yen, Pilsung Kang, Kyoung Jin Lee, Ramachandra R. Dasari, Michael S. Feld, Wonshik Choi Apr 2013

Overcoming The Diffraction Limit Using Multiple Light Scattering In A Highly Disordered Medium, Youngwoon Choi, Taeseok Daniel Yang, Christopher Fang-Yen, Pilsung Kang, Kyoung Jin Lee, Ramachandra R. Dasari, Michael S. Feld, Wonshik Choi

Christopher Fang-Yen

We report that disordered media made of randomly distributed nanoparticles can be used to overcome the diffraction limit of a conventional imaging system. By developing a method to extract the original image information from the multiple scattering induced by the turbid media, we dramatically increase a numerical aperture of the imaging system. As a result, the resolution is enhanced by more than 5 times over the diffraction limit, and the field of view is extended over the physical area of the camera. Our technique lays the foundation to use a turbid medium as a far-field superlens.


Scanner-Free And Wide-Field Endoscopic Imaging By Using A Single Multimode Optical Fiber, Youngwoon Choi, Changhyeong Yoon, Moonseok Kim, Taeseok Daniel Yang, Christopher Fang-Yen, Ramchandra R. Dasari, Kyoung Jin Lee, Wonshik Choi Apr 2013

Scanner-Free And Wide-Field Endoscopic Imaging By Using A Single Multimode Optical Fiber, Youngwoon Choi, Changhyeong Yoon, Moonseok Kim, Taeseok Daniel Yang, Christopher Fang-Yen, Ramchandra R. Dasari, Kyoung Jin Lee, Wonshik Choi

Christopher Fang-Yen

A single multimode fiber is considered an ideal optical element for endoscopic imaging due to the possibility of direct image transmission via multiple spatial modes. However, the wave distortion induced by the mode dispersion has been a fundamental limitation. In this Letter, we propose a method for eliminating the effect of mode dispersion and therefore realize wide-field endoscopic imaging by using only a single multimode fiber with no scanner attached to the fiber. Our method will potentially revolutionize endoscopy in various fields encompassing medicine and industry.


Three-Dimensional Differential Interference Contrast Microscopy Using Synthetic Aperture Imaging, Moonseok Kim, Youngwoon Choi, Christopher Fang-Yen, Yongjin Sung, Kwanhyung Kim, Ramachandra R. Dasari, Michael S. Feld, Wonshik Choi Apr 2013

Three-Dimensional Differential Interference Contrast Microscopy Using Synthetic Aperture Imaging, Moonseok Kim, Youngwoon Choi, Christopher Fang-Yen, Yongjin Sung, Kwanhyung Kim, Ramachandra R. Dasari, Michael S. Feld, Wonshik Choi

Christopher Fang-Yen

We implement differential interference contrast (DIC) microscopy using high-speed synthetic aperture imaging that expands the passband of coherent imaging by a factor of 2.2. For an aperture synthesized coherent image, we apply for the numerical post-processing and obtain a high-contrast DIC image for arbitrary shearing direction and bias retardation. In addition, we obtain images at different depths without a scanning objective lens by numerically propagating the acquired coherent images. Our method achieves high-resolution and high-contrast 3-D DIC imaging of live biological cells. The proposed method will be useful for monitoring 3-D dynamics of intracellular particles.


Stochastic Reconstruction Of Multiple Source Atmospheric Contaminant Dispersion Events, Derek Wade, Inanc Senocak Mar 2013

Stochastic Reconstruction Of Multiple Source Atmospheric Contaminant Dispersion Events, Derek Wade, Inanc Senocak

Inanc Senocak

Reconstruction of intentional or accidental release of contaminants into the atmosphere using concentration measurements from a sensor network constitutes an inverse problem. An added complexity arises when the contaminant is released from multiple sources. Determining the correct number of sources is critical because an incorrect estimation could mislead and delay response efforts. We present a Bayesian inference method coupled with a composite ranking system to reconstruct multiple source contaminant release events. Our approach uses a multi-source data-driven Gaussian plume model as the forward model to predict the concentrations at sensor locations. Bayesian inference with Markov chain Monte Carlo (MCMC) sampling …


Nanoenabled Microelectromechanical Sensor For Volatile Organic Chemical Detection, Chiara Zuniga, Matteo Rinaldi, Samuel M. Khamis, A. T. Johnson, Gianluca Piazza Feb 2013

Nanoenabled Microelectromechanical Sensor For Volatile Organic Chemical Detection, Chiara Zuniga, Matteo Rinaldi, Samuel M. Khamis, A. T. Johnson, Gianluca Piazza

Matteo Rinaldi

A nanoenabled gravimetric chemical sensor prototype based on the large scale integration of single-stranded DNA (ss-DNA) decorated single-walled carbon nanotubes (SWNTs) as nanofunctionalization layer for aluminum nitride contour-mode resonant microelectromechanical (MEM) gravimetric sensors has been demonstrated. The capability of two distinct single strands of DNA bound to SWNTs to enhance differently the adsorption of volatile organic compounds such as dinitroluene (simulant for explosive vapor) and dymethyl-methylphosphonate (simulant for nerve agent sarin) has been verified experimentally. Different levels of sensitivity (17.3 and 28 KHz µm^2/fg) due to separate frequencies of operation (287 and 450 MHz) on the same die have also …


A Thousand Tiny Pieces: The Federal Circuit’S Fractured Myriad Ruling, Lessons To Be Learned, And The Way Forward, Jonathan R. K. Stroud Jan 2013

A Thousand Tiny Pieces: The Federal Circuit’S Fractured Myriad Ruling, Lessons To Be Learned, And The Way Forward, Jonathan R. K. Stroud

Jonathan R. K. Stroud

No abstract provided.


Inhibition Of Bacillus Cereus Growth By Bacteriocin Producing Bacillus Subtilis Isolated From Fermented Baobab Seeds (Maari) Is Substrate Dependent, Donatien Kaboré, Dennis S. Nielsen, Hagrétoui Sawadogo-Lingan, Bréhima Diawara, Mamoudou H. Dicko Prof., Mogens Jakobsen, Line Thorsen Jan 2013

Inhibition Of Bacillus Cereus Growth By Bacteriocin Producing Bacillus Subtilis Isolated From Fermented Baobab Seeds (Maari) Is Substrate Dependent, Donatien Kaboré, Dennis S. Nielsen, Hagrétoui Sawadogo-Lingan, Bréhima Diawara, Mamoudou H. Dicko Prof., Mogens Jakobsen, Line Thorsen

Pr. Mamoudou H. DICKO, PhD

Maari is a spontaneously alkaline fermented food condiment made from baobab tree seeds. Due to the spontaneous nature of maari fermentations growth of the opportunistic human pathogen Bacillus cereus is occasionally observed. Bacillus subtilis strains are important for alkaline seed fermentations because of their enzymatic activities contributing to desirable texture, flavor and pH development. Some B. subtilis strains have antimicrobial properties against B. cereus. In the present work, three bacteriocin producing B. subtilis strains (B3, B122 and B222) isolated from maari were tested. The production of antimicrobial activity by the three strains was found to be greatly influenced by the …


High-Throughput Secondary Screening At The Single-Cell Level, Joseph Robinson Dec 2012

High-Throughput Secondary Screening At The Single-Cell Level, Joseph Robinson

Joseph P Robinson

No abstract provided.


High-Speed Digital Holographic Methods To Characterize The Transient Acousto-Mechanical Response Of Human Tm, I Dobrev, C Furlong, J T. Cheng, J J. Rosowski Dec 2012

High-Speed Digital Holographic Methods To Characterize The Transient Acousto-Mechanical Response Of Human Tm, I Dobrev, C Furlong, J T. Cheng, J J. Rosowski

Ivo Dobrev

Human hearing relies on a delicate sequence of energy transformations from the sound waves in the outer-ear, through mechanical vibrations in the middle-ear, to pressure waves of the fluid in the inner-ear. The investigation of hearing process requires the study of the function of the tympanic membrane (TM) in the energy transformation at the interface of the outer and middle-ear. The investigation of this process requires tools to quantify the acousto-mechanical response of the TM while overcoming the challenges associated with its dimensions, confined location, and the high temporal and spatial complexity of its nanometer scale motions that also relate …


Local Fractional Variational Iteration Method For Fractal Heat Transfer In Silk Cocoon Hierarchy, Ji-Huan He Dec 2012

Local Fractional Variational Iteration Method For Fractal Heat Transfer In Silk Cocoon Hierarchy, Ji-Huan He

Ji-Huan He

A local fractional equation is established for fractal heat transfer in silk cocoon hierarchy, and the local fractional variational iteration method is adopted to solve the equation analytically. The result can well explain the intriguing phenomenon for pupa's survival at extremes of weather from negative 40 degrees to 50 degrees.


A Clinical Comparison Between Two Common Transtibial Prosthetic Suspension Systems, Hossein Gholizadeh Dec 2012

A Clinical Comparison Between Two Common Transtibial Prosthetic Suspension Systems, Hossein Gholizadeh

Hossein Gholizadeh

No abstract provided.