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Full-Text Articles in Biomedical Engineering and Bioengineering

Depleted Energy Charge And Increased Pulmonary Endothelial Permeability Induced By Mitochondrial Complex I Inhibition Are Mitigated By Coenzyme Q1 In The Isolated Perfused Rat Lung, Robert D. Bongard, Ke Yan, Raymond G. Hoffmann, Said H. Audi, Xiao Zhang, Brian J. Lindemer, Mary I. Townsley, Marilyn P. Merker Dec 2013

Depleted Energy Charge And Increased Pulmonary Endothelial Permeability Induced By Mitochondrial Complex I Inhibition Are Mitigated By Coenzyme Q1 In The Isolated Perfused Rat Lung, Robert D. Bongard, Ke Yan, Raymond G. Hoffmann, Said H. Audi, Xiao Zhang, Brian J. Lindemer, Mary I. Townsley, Marilyn P. Merker

Biomedical Engineering Faculty Research and Publications

Mitochondrial dysfunction is associated with various forms of lung injury and disease that also involve alterations in pulmonary endothelial permeability, but the relationship, if any, between the two is not well understood. This question was addressed by perfusing isolated intact rat lung with a buffered physiological saline solution in the absence or presence of the mitochondrial complex I inhibitor rotenone (20 μM). Compared to control, rotenone depressed whole lung tissue ATP from 5.66±0.46 (SEM) to 2.34±0.15 µmol·g−1 dry lung, with concomitant increases in the ADP:ATP and AMP:ATP ratios. Rotenone also ...


Effect Of Tilt Sensor Versus Heel Loading On Neuroprosthesis Stimulation Reliability And Timing For Individuals Post-Stroke During Level And Non- Level Treadmill Walking, M. Barbara Silver-Thorn Oct 2013

Effect Of Tilt Sensor Versus Heel Loading On Neuroprosthesis Stimulation Reliability And Timing For Individuals Post-Stroke During Level And Non- Level Treadmill Walking, M. Barbara Silver-Thorn

Biomedical Engineering Faculty Research and Publications

Study background: Non-level walking may adversely affect stimulation of neuroprostheses as initial programming is performed during level walking. The objectives of this study were to assess stimulation reliability of tilt and heel sensor-based neuroprosthesis stimulation during level and non-level walking, examine stimulation initiation and termination timing during level and non-level walking, and determine whether heel or tilt sensor-based stimulation control is more robust for non-level ambulation. Methods: Eight post-stroke individuals with drop foot who were able to actively ambulate within the community were selected for participation. Each subject acclimated to the neuroprosthesis and walked on a treadmill randomly positioned in ...


Neural Dynamics Of Phonological Processing In The Dorsal Auditory Stream, Einat Liebenthal, Merav Sabri, Scott A. Beardsley, Jain Mangalathu-Arumana, Anjali Desai Sep 2013

Neural Dynamics Of Phonological Processing In The Dorsal Auditory Stream, Einat Liebenthal, Merav Sabri, Scott A. Beardsley, Jain Mangalathu-Arumana, Anjali Desai

Biomedical Engineering Faculty Research and Publications

Neuroanatomical models hypothesize a role for the dorsal auditory pathway in phonological processing as a feedforward efferent system (Davis and Johnsrude, 2007; Rauschecker and Scott, 2009; Hickok et al., 2011). But the functional organization of the pathway, in terms of time course of interactions between auditory, somatosensory, and motor regions, and the hemispheric lateralization pattern is largely unknown. Here, ambiguous duplex syllables, with elements presented dichotically at varying interaural asynchronies, were used to parametrically modulate phonological processing and associated neural activity in the human dorsal auditory stream. Subjects performed syllable and chirp identification tasks, while event-related potentials and functional magnetic ...


How Industry Benefits From Student Design, Jay R. Goldberg Sep 2013

How Industry Benefits From Student Design, Jay R. Goldberg

Biomedical Engineering Faculty Research and Publications

No abstract provided.


Ex Vivo Diffusion Tensor Imaging Of Spinal Cord Injury In Rats Of Varying Degrees Of Severity, Michael Jirjis, Shekar N. Kurpad, Brian D. Schmit Sep 2013

Ex Vivo Diffusion Tensor Imaging Of Spinal Cord Injury In Rats Of Varying Degrees Of Severity, Michael Jirjis, Shekar N. Kurpad, Brian D. Schmit

Biomedical Engineering Faculty Research and Publications

The aim of this study was to characterize magnetic resonance diffusion tensor imaging (DTI) in proximal regions of the spinal cord following a thoracic spinal cord injury (SCI). Sprague–Dawley rats (n = 40) were administered a control, mild, moderate, or severe contusion injury at the T8 vertebral level. Six direction diffusion weighted images (DWIs) were collected ex vivo along the length of the spinal cord, with an echo/repetition time of 31.6 ms/14 sec and b = 500 sec/mm2. Diffusion metrics were correlated to hindlimb motor function. Significant differences were found for whole cord region of interest (ROI ...


Outer Retinal Structure In Best Vitelliform Macular Dystrophy, David B. Kay, Megan E. Land, Robert F. Cooper, Adam M. Dubis, Pooja Godara, Alfredo Dubra, Joseph Carroll, Kimberly E. Stepien Sep 2013

Outer Retinal Structure In Best Vitelliform Macular Dystrophy, David B. Kay, Megan E. Land, Robert F. Cooper, Adam M. Dubis, Pooja Godara, Alfredo Dubra, Joseph Carroll, Kimberly E. Stepien

Biomedical Engineering Faculty Research and Publications

Importance Demonstrating the utility of adaptive optics scanning light ophthalmoscopy (AOSLO) to assess outer retinal structure in Best vitelliform macular dystrophy (BVMD).

Objective To characterize outer retinal structure in BVMD using spectral-domain optical coherence tomography (SD-OCT) and AOSLO.

Design, Setting, and Participants Prospective, observational case series. Four symptomatic members of a family with BVMD with known BEST1 mutation were recruited at the Advanced Ocular Imaging Program research lab at the Medical College of Wisconsin Eye Institute, Milwaukee.

Intervention Thickness of 2 outer retinal layers corresponding to photoreceptor inner and outer segments was measured using SD-OCT. Photoreceptor mosaic AOSLO images within ...


Hypoxia Preconditioning Increases Survival And Decreases Expression Of Toll-Like Receptor 4 In Pulmonary Artery Endothelial Cells Exposed To Lipopolysaccharide, Irshad Ali, Rahul Nanchal, Fouad Husnain, Said H. Audi, G. Ganesh Konduri, John C. Densmore, Meetha Medhora, Elizabeth R. Jacobs Sep 2013

Hypoxia Preconditioning Increases Survival And Decreases Expression Of Toll-Like Receptor 4 In Pulmonary Artery Endothelial Cells Exposed To Lipopolysaccharide, Irshad Ali, Rahul Nanchal, Fouad Husnain, Said H. Audi, G. Ganesh Konduri, John C. Densmore, Meetha Medhora, Elizabeth R. Jacobs

Biomedical Engineering Faculty Research and Publications

Pulmonary or systemic infections and hypoxemic respiratory failure are among the leading causes of admission to intensive care units, and these conditions frequently exist in sequence or in tandem. Inflammatory responses to infections are reproduced by lipopolysaccharide (LPS) engaging Toll-like receptor 4 (TLR4). Apoptosis is a hallmark of lung injury in sepsis. This study was conducted to determine whether preexposure to LPS or hypoxia modulated the survival of pulmonary artery endothelial cells (PAECs). We also investigated the role TLR4 receptor expression plays in apoptosis due to these conditions. Bovine PAECs were cultured in hypoxic or normoxic environments and treated with ...


Few-View Single Photon Emission Computed Tomography (Spect) Reconstruction Based On A Blurred Piecewise Constant Object Model, Paul Arthur Wolf, Jakob S. Jørgensen, Taly Gilat Schmidt, Emil Y. Sidky Aug 2013

Few-View Single Photon Emission Computed Tomography (Spect) Reconstruction Based On A Blurred Piecewise Constant Object Model, Paul Arthur Wolf, Jakob S. Jørgensen, Taly Gilat Schmidt, Emil Y. Sidky

Biomedical Engineering Faculty Research and Publications

A sparsity-exploiting algorithm intended for few-view single photon emission computed tomography (SPECT) reconstruction is proposed and characterized. The algorithm models the object as piecewise constant subject to a blurring operation. To validate that the algorithm closely approximates the true object in the noiseless case, projection data were generated from an object assuming this model and using the system matrix. Monte Carlo simulations were performed to provide more realistic data of a phantom with varying smoothness across the field of view and a cardiac phantom. Reconstructions were performed across a sweep of two primary design parameters. The results demonstrate that the ...


In Vivo Imaging Of Human Retinal Microvasculature Using Adaptive Optics Scanning Light Ophthalmoscope Fluorescein Angiography, Alexander Pinhas, Michael Dubow, Nishit Shah, Toco Y.P. Chui, Drew Scoles, Yusufu N. Sulai, Rishard Weitz, Joseph B. Walsh, Joseph Carroll, Alfredo Dubra, Richard B. Rosen Aug 2013

In Vivo Imaging Of Human Retinal Microvasculature Using Adaptive Optics Scanning Light Ophthalmoscope Fluorescein Angiography, Alexander Pinhas, Michael Dubow, Nishit Shah, Toco Y.P. Chui, Drew Scoles, Yusufu N. Sulai, Rishard Weitz, Joseph B. Walsh, Joseph Carroll, Alfredo Dubra, Richard B. Rosen

Biomedical Engineering Faculty Research and Publications

The adaptive optics scanning light ophthalmoscope (AOSLO) allows visualization of microscopic structures of the human retina in vivo. In this work, we demonstrate its application in combination with oral and intravenous (IV) fluorescein angiography (FA) to the in vivo visualization of the human retinal microvasculature. Ten healthy subjects ages 20 to 38 years were imaged using oral (7 and/or 20 mg/kg) and/or IV (500 mg) fluorescein. In agreement with current literature, there were no adverse effects among the patients receiving oral fluorescein while one patient receiving IV fluorescein experienced some nausea and heaving. We determined that all ...


Reducing Radiation Dose To The Female Breast During Ct Coronary Angiography: A Simulation Study Comparing Breast Shielding, Angular Tube Current Modulation, Reduced Kv, And Partial Angle Protocols Using An Unknown-Location Signal-Detectability Metric, Franco Rupcich, Andreu Badal, Lucretiu M. Popescu, Iacovos Kyprianou, Taly Gilat Schmidt Aug 2013

Reducing Radiation Dose To The Female Breast During Ct Coronary Angiography: A Simulation Study Comparing Breast Shielding, Angular Tube Current Modulation, Reduced Kv, And Partial Angle Protocols Using An Unknown-Location Signal-Detectability Metric, Franco Rupcich, Andreu Badal, Lucretiu M. Popescu, Iacovos Kyprianou, Taly Gilat Schmidt

Biomedical Engineering Faculty Research and Publications

Purpose:

The authors compared the performance of five protocols intended to reduce dose to the breast during computed tomography (CT) coronary angiography scans using a model observer unknown-location signal-detectability metric.

Methods:

The authors simulated CT images of an anthropomorphic female thorax phantom for a 120 kV reference protocol and five “dose reduction” protocols intended to reduce dose to the breast: 120 kV partial angle (posteriorly centered), 120 kV tube-current modulated (TCM), 120 kV with shielded breasts, 80 kV, and 80 kV partial angle (posteriorly centered). Two image quality tasks were investigated: the detection and localization of 4-mm, 3.25 mg ...


Optical Imaging Of Lipopolysaccharide-Induced Oxidative Stress In Acute Lung Injury From Hyperoxia And Sepsis, Reyhaneh Sepehr, Said H. Audi, Sepideh Maleki, Kevin Staniszewski, Annie L. Eis, Girija G. Konduri, Mahsa Ranji Jul 2013

Optical Imaging Of Lipopolysaccharide-Induced Oxidative Stress In Acute Lung Injury From Hyperoxia And Sepsis, Reyhaneh Sepehr, Said H. Audi, Sepideh Maleki, Kevin Staniszewski, Annie L. Eis, Girija G. Konduri, Mahsa Ranji

Biomedical Engineering Faculty Research and Publications

Reactive oxygen species (ROS) have been implicated in the pathogenesis of many acute and chronic pulmonary disorders such as acute lung injury (ALI) in adults and bronchopulmonary dysplasia (BPD) in premature infants. Bacterial infection and oxygen toxicity, which result in pulmonary vascular endothelial injury, contribute to impaired vascular growth and alveolar simplification seen in the lungs of premature infants with BPD. Hyperoxia induces ALI, reduces cell proliferation, causes DNA damage and promotes cell death by causing mitochondrial dysfunction. The objective of this study was to use an optical imaging technique to evaluate the variations in fluorescence intensities of the auto-fluorescent ...


Extra-Matrix Mg2+ Limits Ca2+ Uptake And Modulates Ca2+ Uptake-Independent Respiration And Redox State In Cardiac Isolated Mitochondria, Age D. Boelens, Ranjan K. Pradhan, Christoph A. Blomeyer, Amadou K.S. Camara, Ranjan K. Dash, David F. Stowe Jun 2013

Extra-Matrix Mg2+ Limits Ca2+ Uptake And Modulates Ca2+ Uptake-Independent Respiration And Redox State In Cardiac Isolated Mitochondria, Age D. Boelens, Ranjan K. Pradhan, Christoph A. Blomeyer, Amadou K.S. Camara, Ranjan K. Dash, David F. Stowe

Biomedical Engineering Faculty Research and Publications

Cardiac mitochondrial matrix (m) free Ca2+ ([Ca2+]m) increases primarily by Ca2+ uptake through the Ca2+ uniporter (CU). Ca2+ uptake via the CU is attenuated by extra-matrix (e) Mg2+ ([Mg2+]e). How [Ca2+]m is dynamically modulated by interacting physiological levels of [Ca2+]e and [Mg2+]e and how this interaction alters bioenergetics are not well understood. We postulated that as [Mg2+]e modulates Ca2+ uptake via the CU, it also alters bioenergetics in a matrix Ca2+–induced and matrix Ca2+–independent manner. To test this ...


North American Consortium On Rehabilitation Engineering And Technology For The Individual (Nareti), M. Barbara Silver-Thorn Phd, Karla Bustamante Jun 2013

North American Consortium On Rehabilitation Engineering And Technology For The Individual (Nareti), M. Barbara Silver-Thorn Phd, Karla Bustamante

Biomedical Engineering Faculty Research and Publications

No abstract provided.


Separation Of Visual And Motor Workspaces During Targeted Reaching Results In Limited Generalization Of Visuomotor Adaptation, Yuming Lei, Michelle J. Johnson, Jinsung Wang Apr 2013

Separation Of Visual And Motor Workspaces During Targeted Reaching Results In Limited Generalization Of Visuomotor Adaptation, Yuming Lei, Michelle J. Johnson, Jinsung Wang

Biomedical Engineering Faculty Research and Publications

Separating visual and proprioceptive information in terms of workspace locations during reaching movement has been shown to disturb transfer of visuomotor adaptation across the arms. Here, we investigated whether separating visual and motor workspaces would also disturb generalization of visuomotor adaptation across movement conditions within the same arm. Subjects were divided into four experimental groups (plus three control groups). The first two groups adapted to a visual rotation under a “dissociation” condition in which the targets for reaching movement were presented in midline while their arm performed reaching movement laterally. Following that, they were tested in an “association” condition in ...


Surface Fluorescence Studies Of Tissue Mitochondrial Redox State In Isolated Perfused Rat Lungs, Kevin Staniszewski, Said H. Audi, Reyhaneh Sepehr, Elizabeth R. Jacobs, Mahsa Ranji Apr 2013

Surface Fluorescence Studies Of Tissue Mitochondrial Redox State In Isolated Perfused Rat Lungs, Kevin Staniszewski, Said H. Audi, Reyhaneh Sepehr, Elizabeth R. Jacobs, Mahsa Ranji

Biomedical Engineering Faculty Research and Publications

We designed a fiber-optic-based optoelectronic fluorometer to measure emitted fluorescence from the auto-fluorescent electron carriers NADH and FAD of the mitochondrial electron transport chain (ETC). The ratio of NADH to FAD is called the redox ratio (RR = NADH/FAD) and is an indicator of the oxidoreductive state of tissue. We evaluated the fluorometer by measuring the fluorescence intensities of NADH and FAD at the surface of isolated, perfused rat lungs. Alterations of lung mitochondrial metabolic state were achieved by the addition of rotenone (complex I inhibitor), potassium cyanide (KCN, complex IV inhibitor) and/or pentachlorophenol (PCP, uncoupler) into the perfusate ...


Field Experience As The Centerpiece Of An Integrated Model For Stem Teacher Preparation, Leigh A. Van Den Kieboom, Jill Mcnew-Birren, Ellen Eckman, M. Barbara Silver-Thorn Apr 2013

Field Experience As The Centerpiece Of An Integrated Model For Stem Teacher Preparation, Leigh A. Van Den Kieboom, Jill Mcnew-Birren, Ellen Eckman, M. Barbara Silver-Thorn

Biomedical Engineering Faculty Research and Publications

The purpose of this study was to provide a descriptive account of one pathway for preparing high-quality STEM (science, technology, engineering, and mathematics) teachers for work in high-need urban schools. In this account, we discuss the supports that STEM majors need in learning how to think about the content that they know well, through an educational perspective that focuses on teaching and learning. We also describe the approach that we use that integrates content knowledge, pedagogical content knowledge, and three extensive teaching co-op experiences to facilitate the transition from successful STEM undergraduate students to effective teachers of STEM content. We ...


Brief Report: Visuo-Spatial Guidance Of Movement During Gesture Imitation And Mirror Drawing In Children With Autism Spectrum Disorders, Nicole M.G. Salowitz, Petra Eccarius, Audrey Meyer Carson, Kirsten A. Schohl, Sheryl Jayne Stevens, Amy Vaughan Van Hecke, Robert A. Scheidt Apr 2013

Brief Report: Visuo-Spatial Guidance Of Movement During Gesture Imitation And Mirror Drawing In Children With Autism Spectrum Disorders, Nicole M.G. Salowitz, Petra Eccarius, Audrey Meyer Carson, Kirsten A. Schohl, Sheryl Jayne Stevens, Amy Vaughan Van Hecke, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

Thirteen autistic and 14 typically developing children (controls) imitated hand/arm gestures and performed mirror drawing; both tasks assessed ability to reorganize the relationship between spatial goals and the motor commands needed to acquire them. During imitation, children with autism were less accurate than controls in replicating hand shape, hand orientation, and number of constituent limb movements. During shape tracing, children with autism performed accurately with direct visual feedback, but when viewing their hand in a mirror, some children with autism generated fewer errors than controls whereas others performed much worse. Large mirror drawing errors correlated with hand orientation and ...


Mitochondrial Handling Of Excess Ca2+ Is Substrate-Dependent With Implications For Reactive Oxygen Species Generation, Mohammed Aldakkak, David F. Stowe, Ranjan K. Dash, Amadou K.S. Camara Mar 2013

Mitochondrial Handling Of Excess Ca2+ Is Substrate-Dependent With Implications For Reactive Oxygen Species Generation, Mohammed Aldakkak, David F. Stowe, Ranjan K. Dash, Amadou K.S. Camara

Biomedical Engineering Faculty Research and Publications

The mitochondrial electron transport chain is the major source of reactive oxygen species (ROS) during cardiac ischemia. Several mechanisms modulate ROS production; one is mitochondrial Ca2+ uptake. Here we sought to elucidate the effects of extramitochondrial Ca2+ (e[Ca2+]) on ROS production (measured as H2O2 release) from complexes I and III. Mitochondria isolated from guinea pig hearts were preincubated with increasing concentrations of CaCl2 and then energized with the complex I substrate Na+ pyruvate or the complex II substrate Na+ succinate. Mitochondrial H2O2 release rates were assessed after giving either ...


Protection Against Cardiac Injury By Small Ca2 +-Sensitive K+ Channels Identified In Guinea Pig Cardiac Inner Mitochondrial Membrane, David F. Stowe, Ashish K. Gadicherla, Yifan Zhou, Mohammed Aldakkak, Qunli Cheng, Wai-Meng Kwok, Ming Tao Jiang, James S. Heisner, Meiying Yang, Amadou K.S. Camara Feb 2013

Protection Against Cardiac Injury By Small Ca2 +-Sensitive K+ Channels Identified In Guinea Pig Cardiac Inner Mitochondrial Membrane, David F. Stowe, Ashish K. Gadicherla, Yifan Zhou, Mohammed Aldakkak, Qunli Cheng, Wai-Meng Kwok, Ming Tao Jiang, James S. Heisner, Meiying Yang, Amadou K.S. Camara

Biomedical Engineering Faculty Research and Publications

We tested if small conductance, Ca2 +‐sensitive K+ channels (SKCa) precondition hearts against ischemia reperfusion (IR) injury by improving mitochondrial (m) bioenergetics, if O2‐derived free radicals are required to initiate protection via SKCa channels, and, importantly, if SKCa channels are present in cardiac cell inner mitochondrial membrane (IMM). NADH and FAD, superoxide (O2), and m[Ca2 +] were measured in guinea pig isolated hearts by fluorescence spectrophotometry. SKCa and IKCa channel opener DCEBIO (DCEB) was given for 10 min and ended 20 min before IR. Either TBAP, a dismutator of O ...


Long-Term Follow Up Of Van Nes Rotationplasty For Congenital Proximal Focal Femoral Deficiency, Jeffrey D. Ackman, Haluk Altiok, Ann Flanagan, Mary Peer, Adam Graf, Joseph Krzak, Sahar Hassani, Dan C. Eastwood, Gerald F. Harris Feb 2013

Long-Term Follow Up Of Van Nes Rotationplasty For Congenital Proximal Focal Femoral Deficiency, Jeffrey D. Ackman, Haluk Altiok, Ann Flanagan, Mary Peer, Adam Graf, Joseph Krzak, Sahar Hassani, Dan C. Eastwood, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

Van Nes rotationplasty may be used for patients with congenital proximal focal femoral deficiency (PFFD). The lower limb is rotated to use the ankle and foot as a functional knee joint within a prosthesis. A small series of cases was investigated to determine the long-term outcome. At a mean of 21.5 years (11 to 45) after their rotationplasty, a total of 12 prosthetic patients completed the Short-Form (SF)-36, Faces Pain Scale-Revised, Harris hip score, Oswestry back pain score and Prosthetic Evaluation Questionnaires, as did 12 age- and gender-matched normal control participants. A physical examination and gait analysis, computerised ...


3d Visualization Of Reference-Point Indentation In Human And Murine Bone, John Jameson, Alex Proctor, Carolyne Albert, Gerald F. Harris Jan 2013

3d Visualization Of Reference-Point Indentation In Human And Murine Bone, John Jameson, Alex Proctor, Carolyne Albert, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

No abstract provided.


3d Micron-Scale Imaging Of The Cortical Bone Canal Network In Human Osteogenesis Imperfecta (Oi), John R. Jameson, Carolyne Albert, Bjoern Busse, Peter A. Smith, Gerald F. Harris Jan 2013

3d Micron-Scale Imaging Of The Cortical Bone Canal Network In Human Osteogenesis Imperfecta (Oi), John R. Jameson, Carolyne Albert, Bjoern Busse, Peter A. Smith, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

Osteogenesis imperfecta (OI) is a genetic disorder leading to increased bone fragility. Recent work has shown that the hierarchical structure of bone plays an important role in determining its mechanical properties and resistance to fracture. The current study represents one of the first attempts to characterize the 3D structure and composition of cortical bone in OI at the micron-scale. A total of 26 pediatric bone fragments from 18 individuals were collected during autopsy (Nc=5) or routing orthopaedic procedures (NOI=13) and imaged by microtomography with a synchrotron light source (SRµCT) for several microstructural parameters including cortical porosity ...


In Vivo Dark-Field Imaging Of The Retinal Pigment Epithelium Cell Mosaic, Drew Scoles, Yusufu N. Sulai, Alfredo Dubra Jan 2013

In Vivo Dark-Field Imaging Of The Retinal Pigment Epithelium Cell Mosaic, Drew Scoles, Yusufu N. Sulai, Alfredo Dubra

Biomedical Engineering Faculty Research and Publications

Non-invasive reflectance imaging of the human RPE cell mosaic is demonstrated using a modified confocal adaptive optics scanning light ophthalmoscope (AOSLO). The confocal circular aperture in front of the imaging detector was replaced with a combination of a circular aperture 4 to 16 Airy disks in diameter and an opaque filament, 1 or 3 Airy disks thick. This arrangement reveals the RPE cell mosaic by dramatically attenuating the light backscattered by the photoreceptors. The RPE cell mosaic was visualized in all 7 recruited subjects at multiple retinal locations with varying degrees of contrast and cross-talk from the photoreceptors. Various experimental ...


Brittle Bone Fracture Risk With Transverse Isotropy, Jessica M. Fritz, Nicole M. Grosland, Peter A. Smith, Gerald F. Harris Jan 2013

Brittle Bone Fracture Risk With Transverse Isotropy, Jessica M. Fritz, Nicole M. Grosland, Peter A. Smith, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

No abstract provided.


A Hands-On, Active Learning Approach To Increasing Manufacturing Knowledge In Engineering Students, Jay R. Goldberg, David B. Rank Jan 2013

A Hands-On, Active Learning Approach To Increasing Manufacturing Knowledge In Engineering Students, Jay R. Goldberg, David B. Rank

Biomedical Engineering Faculty Research and Publications

This paper describes a new learning module implemented as part of the senior capstone design course at Marquette University to teach engineering students about basic manufacturing processes, lean manufacturing principles, and design for manufacturability. The module includes several examples of active and student centered learning as part of an in-class assembly line simulation exercise. Students reflected on this experience, and suggested process improvements to save time, reduce cost and waste, and improve the assembly line process. They learned of the importance of manufacturing documentation, process design, and design for assembly. At the end of the module, students understood the importance ...


Improving Brain–Machine Interface Performance By Decoding Intended Future Movements, Francis R. Willett, Aaron J. Suminski, Andrew H. Fagg, Nicholas G. Hatsopoulos Jan 2013

Improving Brain–Machine Interface Performance By Decoding Intended Future Movements, Francis R. Willett, Aaron J. Suminski, Andrew H. Fagg, Nicholas G. Hatsopoulos

Biomedical Engineering Faculty Research and Publications

Objective. A brain–machine interface (BMI) records neural signals in real time from a subject's brain, interprets them as motor commands, and reroutes them to a device such as a robotic arm, so as to restore lost motor function. Our objective here is to improve BMI performance by minimizing the deleterious effects of delay in the BMI control loop. We mitigate the effects of delay by decoding the subject's intended movements a short time lead in the future. Approach. We use the decoded, intended future movements of the subject as the control signal that drives the movement of ...


Visuomotor Learning Enhanced By Augmenting Instantaneous Trajectory Error Feedback During Reaching, James L. Patton, John Wei Yejun, Preeti Bajaj, Robert A. Scheidt Jan 2013

Visuomotor Learning Enhanced By Augmenting Instantaneous Trajectory Error Feedback During Reaching, James L. Patton, John Wei Yejun, Preeti Bajaj, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

We studied reach adaptation to a 30u visuomotor rotation to determine whether augmented error feedback can promote faster and more complete motor learning. Four groups of healthy adults reached with their unseen arm to visual targets surrounding a central starting point. A manipulandum tracked hand motion and projected a cursor onto a display immediately above the horizontal plane of movement. For one group, deviations from the ideal movement were amplified with a gain of 2 whereas another group experienced a gain of 3.1. The third group experienced an offset equal to the average error seen in the initial perturbations ...


Biomechanical Modeling Of Pediatric Clubfoot, Gerald F. Harris Jan 2013

Biomechanical Modeling Of Pediatric Clubfoot, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

No abstract provided.


Markerless Analysis Of Upper Extremity Kinematics During Standardized Pediatric Functional Assessment With A Low-Cost Motion Analysis System, Gerald F. Harris, Susan A. Riedel Jan 2013

Markerless Analysis Of Upper Extremity Kinematics During Standardized Pediatric Functional Assessment With A Low-Cost Motion Analysis System, Gerald F. Harris, Susan A. Riedel

Biomedical Engineering Faculty Research and Publications

No abstract provided.


Comparison Of Randomized Multifocal Mapping And Temporal Phase Mapping Of Visual Cortex For Clinical Use, Yan Ma, B. Douglas Ward, Kristina M. Ropella, Edgar A. Deyoe Jan 2013

Comparison Of Randomized Multifocal Mapping And Temporal Phase Mapping Of Visual Cortex For Clinical Use, Yan Ma, B. Douglas Ward, Kristina M. Ropella, Edgar A. Deyoe

Biomedical Engineering Faculty Research and Publications

fMRI is becoming an important clinical tool for planning and guidance of surgery to treat brain tumors, arteriovenous malformations, and epileptic foci. For visual cortex mapping, the most popular paradigm by far is temporal phase mapping, although random multifocal stimulation paradigms have drawn increased attention due to their ability to identify complex response fields and their random properties. In this study we directly compared temporal phase and multifocal vision mapping paradigms with respect to clinically relevant factors including: time efficiency, mapping completeness, and the effects of noise. Randomized, multifocal mapping accurately decomposed the response of single voxels to multiple stimulus ...