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Full-Text Articles in Engineering

P&O, Arezoo Eshraghi Dec 2013

P&O, Arezoo Eshraghi

AREZOO ESHRAGHI

No abstract provided.


کارگاه اصول نگارش مقالات علمی 1, Dr Alireza Zolfaghari Dec 2013

کارگاه اصول نگارش مقالات علمی 1, Dr Alireza Zolfaghari

Dr Alireza Zolfaghari

No abstract provided.


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 …


Fgf2-Induced Effects On Transcriptome Associated With Regeneration Competence In Adult Human Fibroblasts, Sakthikumar Ambady, Olga Kashpur, David Lapointe, Elizabeth Ryder, Tanja Dominko Sep 2013

Fgf2-Induced Effects On Transcriptome Associated With Regeneration Competence In Adult Human Fibroblasts, Sakthikumar Ambady, Olga Kashpur, David Lapointe, Elizabeth Ryder, Tanja Dominko

Sakthikumar Ambady

Adult human fibroblasts grown in low oxygen and with FGF2 supplementation have the capacity to tip the healing outcome of skeletal muscle injury - by favoring regeneration response in vivo over scar formation. Here, we compare the transcriptomes of control adult human dermal fibroblasts and induced regeneration-competent (iRC) fibroblasts to identify transcriptional changes that may be related to their regeneration competence. RESULTS: We identified a unique gene-expression profile that characterizes FGF2-induced iRC fibroblast phenotype. Significantly differentially expressed genes due to FGF2 treatment were identified and analyzed to determine overrepresented Gene Ontology terms. Genes belonging to extracellular matrix components, adhesion molecules, …


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 …


Developing A Small-Footprint Bioengineering Program, Alisha Sarang-Sieminski, Debbie Chachra Sep 2013

Developing A Small-Footprint Bioengineering Program, Alisha Sarang-Sieminski, Debbie Chachra

Alisha L. Sarang-Sieminski

The field of bioengineering is rapidly changing and expanding to include not only more traditional bioengineering applications (e.g. device-focused areas such as prosthetics, imaging) but also more recent sub-fields and technologies(e.g. more biologically-focused areas such as those enabled by tissue engineering and microfluidics). This rapid change, coupled with the intrinsically interdisciplinary nature of bioengineering, presents a unique challenge to the developers of academic programs, as they need to both select relevant content and strike a balance between depth and breadth. We, the architects of the bioengineering program at the undergraduate-only Franklin W. Olin College of Engineering, which enrolled its first …


Motion And Force Transmission Of A Flexible Instrument Inside A Curved Endoscope, Jitendra P. Khatait Sep 2013

Motion And Force Transmission Of A Flexible Instrument Inside A Curved Endoscope, Jitendra P. Khatait

Jitendra P Khatait

Flexible instruments are increasingly used to perform advanced and complex surgical procedures either manually or robotically. The success of flexible instruments in surgery requires high motion and force fidelity, and controllability of the tip. However, the friction and the limited stiffness of such instruments limit their motion and force transmission. The implementation of flexible instruments in surgery necessitates their characterization, the development of proper tools to understand the effect of various mechanical parameters on their overall performance, and an improvement in motion and force fidelity. Therefore, this thesis describes 2-D and 3-D flexible multibody models of a flexible surgical instrument …


A Study On Correlation Between Consciousness Level And Performance Of The Worker, Devendra Kumar Chaturvedi Dr., Manish Kumar Arya Aug 2013

A Study On Correlation Between Consciousness Level And Performance Of The Worker, Devendra Kumar Chaturvedi Dr., Manish Kumar Arya

Manish Kumar Arya

Consciousness is significantly related to workplace performance among managers and workers. A considerable amount of research indicates that consciousness is one of the best predictors of performance in the workplace. Conscious employees are generally more reliable, more motivated, and harder working. They have also lower rate of absenteeism and counterproductive work behaviours such as stealing and fighting with other employees. Furthermore, consciousness is the only personality trait that correlates with performance across all categories of jobs. This is a pilot study to determine the workers performance related with consciousness. The consciousness will be experimentally measured using the self developed sensor …


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 …


Computational Design Optimization For Microfluidic Magnetophoresis, Brian Plouffe, Laura Lewis, Shashi Murthy Jul 2013

Computational Design Optimization For Microfluidic Magnetophoresis, Brian Plouffe, Laura Lewis, Shashi Murthy

Shashi K. Murthy

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 …


Nonlinear Strain Stiffening Is Not Sufficient To Explain How Far Cells Can Feel On Fibrous Protein Gels., Kristen Billiar, Mathilda Rudnicki, Heather Cirka, Maziar Aghvami, Edward Sander, Qi Wen Jul 2013

Nonlinear Strain Stiffening Is Not Sufficient To Explain How Far Cells Can Feel On Fibrous Protein Gels., Kristen Billiar, Mathilda Rudnicki, Heather Cirka, Maziar Aghvami, Edward Sander, Qi Wen

Kristen L. Billiar

Recent observations suggest that cells on fibrous extracellular matrix materials sense mechanical signals over much larger distances than they do on linearly elastic synthetic materials. In this work, we systematically investigate the distance fibroblasts can sense a rigid boundary through fibrous gels by quantifying the spread areas of human lung fibroblasts and 3T3 fibroblasts cultured on sloped collagen and fibrin gels. The cell areas gradually decrease as gel thickness increases from 0 to 150 μm, with characteristic sensing distances of >65 μm below fibrin and collagen gels, and spreading affected on gels as thick as 150 μm. These results demonstrate …


Measuring The Mechanical Properties Of Living Cells Using Atomic Force Microscopy, Nancy Burnham, Gawain Thomas, Terri Camesano, Qi Wen Jun 2013

Measuring The Mechanical Properties Of Living Cells Using Atomic Force Microscopy, Nancy Burnham, Gawain Thomas, Terri Camesano, Qi Wen

Nancy A. Burnham

Mechanical properties of cells and extracellular matrix (ECM) play important roles in many biological processes including stem cell differentiation, tumor formation, and wound healing. Changes in stiffness of cells and ECM are often signs of changes in cell physiology or diseases in tissues. Hence, cell stiffness is an index to evaluate the status of cell cultures. Among the multitude of methods applied to measure the stiffness of cells and tissues, micro-indentation using an Atomic Force Microscope (AFM) provides a way to reliably measure the stiffness of living cells. This method has been widely applied to characterize the micro-scale stiffness for …


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 …


Hir Prosthetics Research Group Achievements: Road To Success, Arezoo Eshraghi May 2013

Hir Prosthetics Research Group Achievements: Road To Success, Arezoo Eshraghi

AREZOO ESHRAGHI

No abstract provided.


Magnetic Suspension System, Arezoo Eshraghi May 2013

Magnetic Suspension System, Arezoo Eshraghi

AREZOO ESHRAGHI

No abstract provided.


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.


Iranian Elites, Arezoo Eshraghi Apr 2013

Iranian Elites, Arezoo Eshraghi

AREZOO ESHRAGHI

No abstract provided.


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 …


Parallel Recording Of Neurotransmitters Release From Chromaffin Cells Using A 10 X 10 Cmos Ic Potentiostat Array With On-Chip Working Electrodes, Brian Kim, Adam Herbst, Sung Kim, Bradley Minch, Manfred Lindau Feb 2013

Parallel Recording Of Neurotransmitters Release From Chromaffin Cells Using A 10 X 10 Cmos Ic Potentiostat Array With On-Chip Working Electrodes, Brian Kim, Adam Herbst, Sung Kim, Bradley Minch, Manfred Lindau

Bradley Minch

Neurotransmitter release is modulated by many drugs and molecular manipulations. We present an active CMOS-based electrochemical biosensor array with high throughput capability (100 electrodes) for on-chip amperometric measurement of neurotransmitter release. The high-throughput of the biosensor array will accelerate the data collection needed to determine statistical significance of changes produced under varying conditions, from several weeks to a few hours. The biosensor is designed and fabricated using a combination of CMOS integrated circuit (IC) technology and a photolithography process to incorporate platinum working electrodes on-chip. We demonstrate the operation of an electrode array with integrated high-gain potentiostats and output time-division …


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.


Development And Application Of A Portable System To Reliably Measure Grip Forces Using Thin-Film Force Sensors, Shane Tornifoglio Jan 2013

Development And Application Of A Portable System To Reliably Measure Grip Forces Using Thin-Film Force Sensors, Shane Tornifoglio

Shane Vincent Tornifoglio

Accurate tracking of hand grip force is an important consideration needed for a robust understanding in the study of human biomechanics. One aspect where it proves useful is in hand-arm vibration, such as from gripping a power tool. Depending on how firmly the user is gripping the tool, they may change their exposure levels to the tool vibration, which can lead to potential disorders such as Hand-Arm Vibration Syndrome (HAVS). A small, battery powered portable force unit has been developed to supply power to, and condition, the signals from eight thin-film force sensors. This gives a better understanding of the …


At89c51 Microcontroller Based Control Model For Hybrid Assistive Limb (Knee ), Suresh L Jan 2013

At89c51 Microcontroller Based Control Model For Hybrid Assistive Limb (Knee ), Suresh L

suresh L

In this paper, a controlling system is implemented for a wearable walking supporting device so called as Hybrid Assistive Limb. The control circuit is implemented without considering the biological signals of the human body for the knee part, which is based on the knee joint moment from the human body model. The control and a driving circuit s are implemented to assistive the knee as for the requir ement of knee joint dynamics.


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 …


Microfabricated Nanotopological Surfaces For Study Of Adhesion-Dependent Cell Mechanosensitivity, Weiqiang Chen, Yubing Sun, Jianping Fu Jan 2013

Microfabricated Nanotopological Surfaces For Study Of Adhesion-Dependent Cell Mechanosensitivity, Weiqiang Chen, Yubing Sun, Jianping Fu

Weiqiang Chen

Cells exhibit high sensitivity and diverse responses to the intrinsic nanotopography of the extracellular matrix through their nanoscale cellular sensing machinery. A simple microfabrication method for precise control and spatial patterning of the local nanoroughness on glass surfaces by using photolithography and reactive ion etching is reported. It is demonstrated that local nanoroughness as a biophysical cue could regulate a diverse array of NIH/3T3 fi broblast behaviors, including cell morphology, adhesion, proliferation, migration, and cytoskeleton contractility. The capability to control and further predict cellular responses to nanoroughness might suggest novel methods for developing biomaterials mimicking nanotopographic structures in vivo for …