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Full-Text Articles in Biomedical Engineering and Bioengineering

Challenges Of Erau’S First Suborbital Flight Aboard Blue Origin’S New Shepard M7 For The Cell Research Experiment In Microgravity (Crexim), Pedro Llanos, Kristina Andrijauskaite, Vijay V. Duraisamy, Francisco F. Pastrana, Erik Seedhouse, Sathya Gangadharan, Leonid Bunegin, Mariel Rico Jun 2019

Challenges Of Erau’S First Suborbital Flight Aboard Blue Origin’S New Shepard M7 For The Cell Research Experiment In Microgravity (Crexim), Pedro Llanos, Kristina Andrijauskaite, Vijay V. Duraisamy, Francisco F. Pastrana, Erik Seedhouse, Sathya Gangadharan, Leonid Bunegin, Mariel Rico

Pedro J. Llanos (www.AstronauticsLlanos.com)

Cell Research Experiment In Microgravity (CRExIM) was launched aboard Blue Origin’s New Shepard suborbital vehicle on Tuesday, December 12, 2017, from the West Texas Launch Site in Van Horn, Texas. One of the aims of this science experiment was to assess the effects of microgravity on murine T-cells during suborbital flight. These cells were placed in a NanoLab with a data logger that sensed the acceleration, temperature, and relative humidity during preflight, flight, and postflight operations. Some discrepancies in sensor measurement were noticed, and these errors were attributed partly to the difference in sampling rates and partly to the different …


Person Identification From Streaming Surveillance Video Using Mid-Level Features From Joint Action-Pose Distribution, Binu M. Nair, Vijayan K. Asari Oct 2016

Person Identification From Streaming Surveillance Video Using Mid-Level Features From Joint Action-Pose Distribution, Binu M. Nair, Vijayan K. Asari

Vijayan K. Asari

We propose a real time person identification algorithm for surveillance based scenarios from low-resolution streaming video, based on mid-level features extracted from the joint distribution of various types of human actions and human poses. The proposed algorithm uses the combination of an auto-encoder based action association framework which produces per-frame probability estimates of the action being performed, and a pose recognition framework which gives per-frame body part locations. The main focus in this manuscript is to effectively combine these per-frame action probability estimates and pose trajectories from a short temporal window to obtain mid-level features. We demonstrate that these mid-level …


Concept Frequency Distribution In Biomedical Text Summarization, Lawrence H. Reeve, Hyoil Han, Saya V. Nagori, Jonathan C. Yang, Tamara A. Schwimmer, Ari D. Brooks Sep 2015

Concept Frequency Distribution In Biomedical Text Summarization, Lawrence H. Reeve, Hyoil Han, Saya V. Nagori, Jonathan C. Yang, Tamara A. Schwimmer, Ari D. Brooks

Hyoil Han

Text summarization is a data reduction process. The use of text summarization enables users to reduce the amount of text that must be read while still assimilating the core information. The data reduction offered by text summarization is particularly useful in the biomedical domain, where physicians must continuously find clinical trial study information to incorporate into their patient treatment efforts. Such efforts are often hampered by the high-volume of publications. Our contribution is two-fold: 1) to propose the frequency of domain concepts as a method to identify important sentences within a full-text; and 2) propose a novel frequency distribution model …


Three-Dimensional Confocal Microscopy Indentation Method For Hydrogel Elasticity Measurement, Donghee Lee, Md Mahmudur Rahman, You Zhou, Sangjin Ryu Aug 2015

Three-Dimensional Confocal Microscopy Indentation Method For Hydrogel Elasticity Measurement, Donghee Lee, Md Mahmudur Rahman, You Zhou, Sangjin Ryu

Md Mahmudur Rahman

No abstract provided.


Three-Dimensional Vibrometry Of The Human Eardrum With Stroboscopic Lensless Digital Holography, Morteza Khaleghi, Cosme Furlong, Mike Ravicz, Jeffrey T. Cheng, John J. Rosowski Apr 2015

Three-Dimensional Vibrometry Of The Human Eardrum With Stroboscopic Lensless Digital Holography, Morteza Khaleghi, Cosme Furlong, Mike Ravicz, Jeffrey T. Cheng, John J. Rosowski

Morteza Khaleghi

The eardrum or tympanic membrane (TM) transforms acoustic energy at the ear canal into mechanical motions of the ossicles. The acousto-mechanical transformer behavior of the TM is determined by its shape, three-dimensional (3-D) motion, and mechanical properties. We have developed an optoelectronic holographic system to measure the shape and 3-D sound-induced displacements of the TM. The shape of the TM is measured with dual-wavelength holographic contouring using a tunable near IR laser source with a central wavelength of 780 nm. 3-D components of sound-induced displacements of the TM are measured with the method of multiple sensitivity vectors using stroboscopic holographic …


Developments In Opto-Electronic Holography (Oeh) For Measurement Of Sound-Induced Eardrum Motion, Ivo Dobrev, Jeffrey Tao Cheng, Morteza Khaleghi, Jérémie Guignard, Michael E. Ravicz, John J. Rosowski, Cosme Furlong Mar 2015

Developments In Opto-Electronic Holography (Oeh) For Measurement Of Sound-Induced Eardrum Motion, Ivo Dobrev, Jeffrey Tao Cheng, Morteza Khaleghi, Jérémie Guignard, Michael E. Ravicz, John J. Rosowski, Cosme Furlong

Ivo Dobrev

Prior to 2009 the data available to characterize the function of the mammalian eardrum was rather limited and consisted of time-averaged holograms gathered 30 to 40 years previously or laser-vibrometer measurements usually made with low spatial density or over small regions of the eardrum. These few measurements could be compared to the plethora of Finite-Element models of eardrum and middle ear function. More recently, a collaboration between an optics group at the Center for Holographic Studies and Laser micro-mechaTronics at the Worcester Polytechnic Institute in Worcester MA and physiologists and acousticians at the Eaton-Peabody Laboratory at the Massachusetts Eye and …


Full-Field Vibrometry By High-Speed Digital Holography For Middle-Ear Mechanics, Ivo Dobrev Aug 2014

Full-Field Vibrometry By High-Speed Digital Holography For Middle-Ear Mechanics, Ivo Dobrev

Ivo Dobrev

Hearing loss affects approximately 1 in 10 people in the world and this percentage is increasing every year. Some of the most common courses for hearing loss are disorders of the human tympanic membrane (TM or eardrum) and middle-ear. Early detection and diagnosis of hearing loss as well as research and understanding of the hearing process depend on medical and research tools for quantification of the hearing capabilities, including the function of the human TM in the complex acoustic-mechanical transformation of environmental sounds into vibrations of the middle- and the inner-ear. Current ear exams are assessing the state of the …


Xena: An Automated 'Open-Source' 129xe Hyperpolarizer For Clinical Use, Panayiotis Nikolaou, Aaron M. Coffey, Laura L. Walkup, Brogan M. Gust, Nicholas Whiting, Hayley Newton, Iga Muradyan, Mikayel Dabaghyan, Kaili Ranta, Gregory D. Moroz, Matthew S. Rosen, Samuel Patz, Michael J. Barlow, Eduard Y. Chekmenev, Boyd M. Goodson Dec 2013

Xena: An Automated 'Open-Source' 129xe Hyperpolarizer For Clinical Use, Panayiotis Nikolaou, Aaron M. Coffey, Laura L. Walkup, Brogan M. Gust, Nicholas Whiting, Hayley Newton, Iga Muradyan, Mikayel Dabaghyan, Kaili Ranta, Gregory D. Moroz, Matthew S. Rosen, Samuel Patz, Michael J. Barlow, Eduard Y. Chekmenev, Boyd M. Goodson

Nicholas Whiting

Here we provide a full report on the construction, components, and capabilities of our consortium’s “opensource”
large-scale (~1 L/h) 129Xe hyperpolarizer for clinical, pre-clinical, and materials NMR/MRI (Nikolaou et al., Proc. Natl. Acad. Sci. USA, 110, 14150 (2013)). The ‘hyperpolarizer’ is automated and built mostly of off-the-shelf components; moreover, it is designed to be cost-effective and installed in both research laboratories and clinical settings with materials costing less than $125,000. The device runs in the xenon-rich regime (up to 1800 Torr Xe in 0.5 L) in either stopped-flow or single-batch mode—making cryo-collection of the hyperpolarized gas unnecessary for many applications. …


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 …


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 …


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.


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 …


Shelf-Life Of Bioprosthetic Heart Valves: A Structural And Mechanical Study, Maryse Julien, Dany Letouneau, Yves Marois, Alain Cardou, Martin King, Robert Guidoin, Debbie Chachra, J. Lee Jul 2012

Shelf-Life Of Bioprosthetic Heart Valves: A Structural And Mechanical Study, Maryse Julien, Dany Letouneau, Yves Marois, Alain Cardou, Martin King, Robert Guidoin, Debbie Chachra, J. Lee

Debbie Chachra

This study was undertaken to evaluate the influence of storage conditions on the shelf-life of porcine bioprosthetic valves. Fifty-five unimplanted porcine bioprostheses have been evaluated. The valves were stored in 0.5% buffered glutaraldehyde solution for different periods of time (7, 23 and 32 months). Twenty-eight valves were refrigerated while the remaining valves were stored at room temperature. The pH of the glutaraldehyde solution at room temperature decreased with time of storage, while that kept in the refrigerator remained stable over the course of the study. Macroscopic observations showed that the valve tissues kept at room temperature, especially for the periods …


Photolithographic Surface Micromachining Of Polydimethylsiloxane (Pdms), Weiqiang Chen, Raymond H. W. Lam, Jianping Fu Nov 2011

Photolithographic Surface Micromachining Of Polydimethylsiloxane (Pdms), Weiqiang Chen, Raymond H. W. Lam, Jianping Fu

Weiqiang Chen

A major technical hurdle in microfluidics is the difficulty in achieving high fidelity lithographic patterning on polydimethylsiloxane (PDMS). Here, we report a simple yet highly precise and repeatable PDMS surface micromachining method using direct photolithography followed by reactive ion etching (RIE). Our method to achieve surface patterning of PDMS applied an O2 plasma treatment to PDMS to activate its surface to overcome the challenge of poor photoresist adhesion on PDMS for photolithography. Our photolithographic PDMS surface micromachining technique is compatible with conventional soft lithography techniques and other silicon-based surface and bulk micromachining methods. To illustrate the general application of our …


Patient Safety: What Can Be Done About It?, Steven Dain Aug 2011

Patient Safety: What Can Be Done About It?, Steven Dain

Steven L Dain

Much is said and written about patient safety. In Canada, a small group of dedicated physicians, nurses and engineers participates in the Canadian Standards Association and Standards Council of Canada Advisory Committees writing basic safety and essential performance requirements for a large range of anesthesia, respiratory care and critical care equipment. Over the past several years, in recognition of the globalization of trade and the international nature of medical device design and manufacturing, Canadian Anesthesiologists’ Society members Dr Steven Dain, Dr Karen Brown, Dr Matt Kurrek, Dr Ken LeDez, and Dr Jeremy Sloan have primarily participated in Organization for International …


Neural Vs. Statistical Classifier In Conjunction With Genetic Algorithm Based Feature Selection, Ping Zhang, Brijesh Verma, Kuldeep Kumar Dec 2009

Neural Vs. Statistical Classifier In Conjunction With Genetic Algorithm Based Feature Selection, Ping Zhang, Brijesh Verma, Kuldeep Kumar

Kuldeep Kumar

Digital mammography is one of the most suitable methods for early detection of breast cancer. It uses digital mammograms to find suspicious areas containing benign and malignant microcalcifications. However, it is very difficult to distinguish benign and malignant microcalcifications. This is reflected in the high percentage of unnecessary biopsies that are performed and many deaths caused by late detection or misdiagnosis. A computer based feature selection and classification system can provide a second opinion to the radiologists in assessment of microcalcifications. The research in this paper proposes and investigates a neural-genetic algorithm for feature selection in conjunction with neural and …


A Hybrid Classifier For Mass Classification With Different Kinds Of Features In Mammography, Ping Zhang, Kuldeep Kumar, Brijesh Verma Dec 2009

A Hybrid Classifier For Mass Classification With Different Kinds Of Features In Mammography, Ping Zhang, Kuldeep Kumar, Brijesh Verma

Kuldeep Kumar

This paper proposes a hybrid system which combines computer extracted features and human interpreted features from the mammogram, with the statistical classifier’s output as another kind of feature in conjunction with a genetic neural network classifier. The hybrid system produced better results than the single statistical classifier and neural network. The highest classification rate reached 91.3%. The area value under the ROC curve is 0.962. The results indicated that the mixed features contribute greatly for the classification of mass patterns into benign and malignant.


Laminar Flow In Mini-Fluidics Channels Assembly And Its Application In Zebra Fish Embryo Research, Radek Glaser Dec 2007

Laminar Flow In Mini-Fluidics Channels Assembly And Its Application In Zebra Fish Embryo Research, Radek Glaser

Radek Glaser

A Mini-Fluidics system was designed to facilitate the muscle growth of the Zebra Fish embryos. This experimental device is made of peristaltic pump, inflow/outflow manifolds, fluid storage tank, series of valves and flexible pipes and the main plate with six mini channels. These closed channels provide pathways for an extremely laminar flow. The Zebra Fish embryos are placed in the channels and exposed to the forces present in the fluid.