Engineering Commons^™

Electrotransfer Of Single-Stranded Or Double-Stranded Dna Induces Complete Regression Of Palpable B16.F10 Mouse Melanomas, Loree Heller, Vesba Todorovic, Maja Cemazar

Bioelectrics Publications

Enhanced tumor delivery of plasmid DNA with electric pulses in vivo has been confirmed in many preclinical models. Intratumor electrotransfer of plasmids encoding therapeutic molecules has reached Phase II clinical trials. In multiple preclinical studies, a reduction in tumor growth, increased survival or complete tumor regression have been observed in control groups in which vector or backbone plasmid DNA electrotransfer was performed. This study explores factors that could produce this antitumor effect. The specific electrotransfer pulse protocol employed significantly potentiated the regression. Tumor regression was observed after delivery of single-stranded or double-stranded DNA with or without CpG motifs in both …

Quantifying Risks Of Climate Change And Sea Level Rise To Naval Station Norfolk (Serdp Rc-1701), Kelly Burks-Copes

October 2, 2013: Quantifying Risks and Moving Forward

No abstract provided.

Correlational Study Of Open Circuit Resonant (Sansec) Sensor’S Electric Field Distribution On Lightning Attachment, Kayla M. Farrow, Linda L. Vahala

Electrical & Computer Engineering Faculty Publications

NASA Langley Research Center (LaRC) is conducting research to develop an open circuit SansEC (Sans Electric Connection) sensor to provide lightning strike protection (LSP) in conjunction with damage detection and diagnosis for composite aircraft. SansEC sensors are simplistic devices consisting of an open circuit conductive trace shaped in a planar geometric spiral. The length and width of the conductive trace as well as the gap separation between adjacent turns determines the inductance, resistance and capacitance of the LRC circuit and its associated resonant response. When the sensor is placed on a composite substrate, the electric impedance of the substrate is …

Complementarities Of Probabilistic And Evidence Approaches: An Uncertainty Assessment For Selection Of Composite Material, Stella B. Bondi, Resit Unal, Patrick T. Hester, Trina M. Chytka

Engineering Technology Faculty Publications

A complimentary probabilistic and evidence theory approach is utilized to enhance uncertainty assessments in the area of critical safety characteristics for conceptual design. This research provides additional exploration into the failure modes necessary to utilize Fiber Reinforced Polymer (FRP) and various composites to their fullest potential and to minimize uncertainty by comparing probability and evidence theories. This combined approach has been applied to a selection of composite material that could provide uncertainty assessment design for a space transportation system. Uncertainty estimates presented are bounded by belief and plausibility functions. The results may provide additional information to the decision makers in …

Atmospheric Pressure He-Air Plasma Jet: Breakdown Process And Propagation Phenomenon, Asma Begum, Mounir Laroussi, Mohammad Rasel Pervez

Electrical & Computer Engineering Faculty Publications

In this paper He-discharge (plasma jet/bullet) in atmospheric pressure air and its progression phenomenon has been studied experimentally using ICCD camera, optical emission spectroscopy (OES) and calibrated dielectric probe measurements. The repetitive nanosecond pulse has applied to a plasma pencil to generate discharge in the helium gas channel. The discharge propagation speed was measured from the ICCD images. The axial electric field distribution in the plasma jet is inferred from the optical emission spectroscopic data and from the probe measurement. The correlation between the jet velocities, jet length with the pulse duration is established. It shows that the plasma jet …

An Engineering Design Stem Project: T-Shirt Launcher, Todd D. Fantz, Melva R. Grant

STEMPS Faculty Publications

Technology education has the potential to be the glue for integrating science, technology, engineering, and mathematics (STEM) education through the use of the design process. This should result in increased student interest in science and math, resulting in increased standardized science and math scores (Silk, C. Schunn, & Strand, 2009). In order for this to happen, students need to integrate their grade-level mathematics and science content knowledge in their technology and/or engineering design (Tran & Nathan, 2010). Hopefully, this can be accomplished without losing student interest generated by hands-on, kinesthetic learning. This article provides one example of getting technology education …

Asbpa Sea Level Rise Findings, Maura Boswell

March 13, 2013: Regional Sea Level Rise Assessment, Adaptation and Flood Mitigation Projects

No abstract provided.

City Of Norfolk Coastal Flood Mitigation Program, Brian Joyner

March 13, 2013: Regional Sea Level Rise Assessment, Adaptation and Flood Mitigation Projects

No abstract provided.

Willoughby Spit Shoreline Improvement Project Of Ocean View Beach, Maura Boswell

March 13, 2013: Regional Sea Level Rise Assessment, Adaptation and Flood Mitigation Projects

No abstract provided.

Fema Region Iii Coastal Storm Surge Study, Mike Forte, Jeff Hanson, Michelle Hamor

March 13, 2013: Regional Sea Level Rise Assessment, Adaptation and Flood Mitigation Projects

No abstract provided.

Usace Flood Risk Management Partners In Shared Responsibility, Michelle Hamor

March 13, 2013: Regional Sea Level Rise Assessment, Adaptation and Flood Mitigation Projects

No abstract provided.

Recurrent Coastal Flooding: How Should Virginia Respond?, Molly Mitchell Rogerro

March 13, 2013: Regional Sea Level Rise Assessment, Adaptation and Flood Mitigation Projects

No abstract provided.

Atomic Force Microscopy Characterization Of Collagen ‘Nanostraws’ In Human Costal Cartilage, Michael W. Stacey, Diganta Dutta, Anthony Asmar, H. Elsayed-Ali, R. Kelly Jr., A. Beskok

Bioelectrics Publications

Costal cartilage, a type of hyaline cartilage that bridges the bony ribs and sternum, is relatively understudied compared to the load bearing cartilages. Deformities of costal cartilage can result in deformation of the chest wall, where the sternum is largely pushed toward or away from the spine, pectus excavatum and pectus carinatum, respectively, with each condition having significant clinical impact. In the absence of extensive literature describing morphological features of costal cartilage, we characterized a sample from the costal margin immunohistologically and through atomic force microscopy. We had previously observed the presence of collagen ‘nanostraws’ running the length of costal …

Induction Of Cell Death Mechanisms And Apoptosis By Nanosecond Pulsed Electric Fields (Nspefs), Stephen J. Beebe, Nova M. Sain, Wei Ren

Bioelectrics Publications

Pulse power technology using nanosecond pulsed electric fields (nsPEFs) offers a new stimulus to modulate cell functions or induce cell death for cancer cell ablation. New data and a literature review demonstrate fundamental and basic cellular mechanisms when nsPEFs interact with cellular targets. NsPEFs supra-electroporate cells creating large numbers of nanopores in all cell membranes. While nsPEFs have multiple cellular targets, these studies show that nsPEF-induced dissipation of DeltaPsim closely parallels deterioration in cell viability. Increases in intracellular Ca2+ alone were not sufficient for cell death; however, cell death depended of the presence of Ca2+. When both events occur, cell …

Web-Based Virtual Learning For Digital Manufacturing Fundamentals For Automotive Workforce Training, Vukica Jovanovic, Nathan W. Hartman

Engineering Technology Faculty Publications

Automotive manufacturers are experiencing difficulties in hiring highly qualified workers with ability to adopt new technologies fast. This kind of ongoing need for training is slowing innovation. This problem is related to the difficulty in obtaining consistent training resources and services especially with lack of training for advanced manufacturing practices for specialised industry sectors. More and more occupations require degrees higher than secondary education because of the global need for so called ‘knowledge workers’. An example of an interactive learning programme, developed with the support of narrated presentation technology, podcasts and online access has been shown in this paper. Sixty …

Clarifications Of A Datum Axis Or Centerplane Specifying In Maximum Material Condition Of Geometric Dimensioning And Tolerancing, Cheng Y. Lin, Jennifer G. Michaeli, Mileta Tomovic

Engineering Technology Faculty Publications

Engineering and Engineering Technology students and professionals learning the processes and standards in computer-aided design (CAD) and computer-aided manufacturing (CAM) should learn and understand the methodology of geometric dimensioning and tolerancing (GD&T) to describe the intent and requirements for part and assembly geometries. Correct application of GD&T ensures that the part and assembly geometry defined on the drawing will have the desired form and fit (within limits) and function as intended. One learning difficulty in understanding GD&T is the concept of defining a datum axis or center plane using Maximum Material Condition (MMC). To overcome this difficulty, a new approach …

Cpg And Interleukin-15 Synergize To Enhance Ifn-Gamma Production By Activated Cd8(+) T Cells, Dustin Cobb, Sigi Guo, Ronald B. Smeltz

Bioelectrics Publications

Interleukin-15 (IL-15) regulates the development and maintenance of memory CD8(+) T cells. Paradoxically, we previously reported that IL-15 could enhance CD8(+) T-cell responses to IL-12, a proinflammatory cytokine required for optimal priming of effector CD8(+) T cells. To expand the physiological relevance of these findings, we tested IL-15 for its ability to enhance T-cell responses to bacterial CpG. Expectedly, CpG enhanced the production of IFN-gamma by CD8(+) T cells polyclonally activated with anti-CD3. However, addition of IL-15 to CpG-stimulated cultures led to a striking increase in IFN-gamma production. The effect of CpG and IL-15 was also evident with CD8(+) T …

Response To "Sodium Current Inhibition By Nanosecond Pulsed Electric Field (Nspef) - Fact Or Artifact?" By Verkerk Et Al, Andrei G. Pakhomov

Bioelectrics Publications

It was nice to learn that our studies of nanosecond pulsed electric field (nsPEF) effects on membrane currents [Nesin et al., 2012; Nesin and Pakhomov, 2012] gained the attention of scientists outside the immediate field of bioelectromagnetics.

Brust-Schiffrin Synthesis Of Catalytic Bipodal Pdpt Nanoparticles With Some Mechanistic Insights, Sangbum Han, Vara P. Sheela, Wei Cao, Balasubramanian Ramjee

Applied Research Center Publications

Brust–Schiffrin reduction of Pd and Pt precursors in the presence of resorcinarene amine surfactant led to the formation of substantially Pt rich, PdPt bimetallic nanoparticles of a V-shape or variants on the V-shape. New insights into this reaction are provided on the basis of reversed Brust–Schiffrin syntheses, DLS, UV-vis, and NMR analysis. Based on our experiments we conclude that the resorcinarene amine surfactant is part of the inverse micelle formed from TOABr and it also selectively complexes with the Pd salts prior to their reduction. Remarkably, the composition of the bipodal nanoparticles could be varied substantially by varying the reaction …

An Empirical Muscle Intracellular Action Potential Model With Multiple Erlang Probability Density Functions Based On A Modified Newton Method, Gyutae Kim, Mohammed M. Ferdjallah, Frederic D. Mckenzie

Computational Modeling & Simulation Engineering Faculty Publications

The convolution of the transmembrane current of an excitable cell and a weighting function generates a single fiber action potential (SFAP) model by using the volume conductor theory. Here, we propose an empirical muscle IAP model with multiple Erlang probability density functions (PDFs) based on a modified Newton method. In addition, we generate SFAPs based on our IAP model and referent sources, and use the peak-to-peak ratios (PPRs) of SFAPs for model verification. Through this verification, we find that the relation between an IAP profile and the PPR of its SFAP is consistent with some previous studies, and our IAP …

Special Issue On Medical Simulation, Michel Audette, Hanif M. Ladak

Computational Modeling & Simulation Engineering Faculty Publications

We would like to welcome you to this Special Issue on Medical Simulation, the first of its kind not only for SIMULATION: Transactions of The Society for Modeling and Simulation International, but for any technical journal. Our respective backgrounds are an indication of the technical and clinical breadth of medical simulation, as we approach the subject as primarily medical image analysis and biomechanics experts respectively, each with a variety of clinical interests spanning virtual reality (VR)–based neuro-, orthopedic and ear-nose-and-throat surgery. Moreover, we believe that the breadth of the papers that comprise this issue reflects an even broader perspective. After …

Orientation Invariant Ecg-Based Stethoscope Tracking For Heart Auscultation Training On Augmented Standardized Patients, Nahom Kidane, Salim Chemlal, Jiang Li, Frederic D. Mckenzie, Tom Hubbard

Computational Modeling & Simulation Engineering Faculty Publications

Auscultation, the act of listening to the heart and lung sounds, can reveal substantial information about patients’ health and other cardiac-related problems; therefore, competent training can be a key for accurate and reliable diagnosis. Standardized patients (SPs), who are healthy individuals trained to portray real patients, have been extensively used for such training and other medical teaching techniques; however, the range of symptoms and conditions they can simulate remains limited since they are only patient actors. In this work, we describe a novel tracking method for placing virtual symptoms in correct auscultation areas based on recorded ECG signals with various …

Recruitment Of The Intracellular Ca2+ By Ultrashort Electric Stimuli: The Impact Of Pulse Duration, Iurii Semenov, Shu Xiao, Olga N. Pakhomova, Andrei G. Pakhomov

Bioelectrics Publications

Nanosecond-duration electric stimuli are distinguished by the ability to permeabilize intracellular membranes and recruit Ca²⁺ from intracellular stores. We quantified this effect in non-excitable cells (CHO) using ratiometric Ca²⁺ imaging with Fura-2. In a Ca²⁺-free medium, 10-, 60-, and 300-ns stimuli evoked Ca2⁺ transients by mobilization of Ca²⁺ from the endoplasmic reticulum. With 2 mM external Ca²⁺, the transients included both extra- and intracellular components. The recruitment of intracellular Ca²⁺ increased as the stimulus duration decreased. At the threshold of 200–300 nM, the transients were amplified by calcium-induced calcium release. We …

Primary Pathways Of Intracellular Ca2+ Mobilization By Nanosecond Pulsed Electric Field, Iurii Semenov, Shu Xiao, Andrei G. Pakhomov

Bioelectrics Publications

Permeabilization of cell membranous structures by nanosecond pulsed electric field (nsPEF) triggers transient rise of cytosolic Ca²⁺ concentration ([Ca²⁺]_i), which determines multifarious downstream effects. By using fast ratiometric Ca²⁺ imaging with Fura-2, we quantified the external Ca²⁺ uptake, compared it with Ca²⁺ release from the endoplasmic reticulum (ER), and analyzed the interplay of these processes. We utilized CHO cells which lack voltage-gated Ca²⁺ channels, so that the nsPEF-induced [Ca²⁺]_i changes could be attributed primarily to electroporation. We found that a single 60-ns pulse caused fast [Ca2+]_i increase …

Real-Time In Vivo Imaging Of Size-Dependent Transport And Toxicity Of Gold Nanoparticles In Zebrafish Embryos Using Single Nanoparticle Plasmonic Spectroscopy, Lauren M. Browning, Tao Huang, Xiao-Hong Nancy Xu

Chemistry & Biochemistry Faculty Publications

Noble metal nanoparticles (NPs) show distinctive plasmonic optical properties and superior photostability, enabling them to serve as photostable multicoloured optical molecular probes and sensors for real-time in vivo imaging. To effectively study biological functions in vivo, it is essential that the NP probes are biocompatible and can be delivered into living organisms non-invasively. In this study, we have synthesized, purified and characterized stable (non-aggregated) gold (Au) NPs (86.2 +/- 10.8 nm). We have developed dark-field single NP plasmonic microscopy and spectroscopy to study their transport into early developing zebrafish embryos (cleavage stage) and their effects on embryonic development …

Product Lifecycle Management: Measuring What Is Important - Product Lifecycle Implementation Maturity Model, Abram Walton, Cynthia Tomovic, Michael Grieves

STEMPS Faculty Publications

Industry reports that benefits of PLM are difficult to assess because the same benefit can be expressed as a function of time, cost, quality, or any combination. Based on a review of the PLM literature in an earlier study, a PLM Process Model and an initial list of PLM related metrics was generated and later confirmed through interviews with experienced PLM users. In the current study, the original PLM Process Model was refined and the list of metrics was subjected to an exploratory factor analysis in which specific metrics were found to be related to one of four factors: Inputs, …

The Effects Of External Motivation And Real-Time Automated Feedback On Speeding Behavior In A Naturalistic Setting, Ian J. Reagan, James P. Bliss, Ron Van Houten, Bryan W. Hilton

Psychology Faculty Publications

Objective: In this field experiment, the authors tested an alerting system and a monetary incentive system with the objective of reducing speeding more than 5 mph faster than the posted speed limit.

Background: Speeding is a factor in a significant number of traffic fatalities. The systems tested in this project have been evaluated outside but not within the United States. These studies indicated that similar systems led to reductions in speeding.

Method: For this study, eight vehicles were instrumented such that vehicle speed and speed limits were linked in real time. A total of 50 participants drove assigned vehicles for …

Determining Stakeholder Influence Using Input-Output Modeling, Patrick T. Hester, Kevin Macg. Adams

Engineering Management & Systems Engineering Faculty Publications

Stakeholders are a vital element in all complex systems problems. They are customers, users, clients, suppliers, employees, and team members. They fund the system, design it, build it, operate it, use it, maintain it, and dispose of it. While many approaches exist for classifying and determining their attitudes, these approaches stop short of evaluating stakeholders in a holistic manner. This paper closes this research gap by developing the metric of stakeholder situation influence, a measure which allows for quantitative evaluation of stakeholder influence on a given problem. This measure is derived from Leontief Input-Output analysis. The developed approach extends previous …

Resilience Governance Through Serious Energy Gaming, Adrian V. Gheorghe, Dan V. Vamanu

Engineering Management & Systems Engineering Faculty Publications

Physical analogies emphasizing cooperative behavior in systems are explored and integrated into so called 'serious energy games', to contribute in a better understanding, monitoring and good governance of some of the complex security issues confronting the evolvement of contemporary energy systems. It is believed that such exercises might be supportive in the necessary attempt, by the many stakeholders and actors / agents involved, to bring balance to prevailing policies of which seems to be “Go change yourself - in a resilient fashion!” An extrapolation of several findings to other than energy systems tempted to implement drastic changes based on substantial …

Perceptions Of New Doctoral Graduates On The Future Of The Profession, John Ritz, Gene Martin

STEMPS Faculty Publications

Advancement of a profession relies heavily on the participation of its members. Leadership roles must be filled at many levels. To effectively prepare future leaders, efforts must be undertaken to educate and mentor them both about their professions and how to lead within them. The authors sought to identify the perceptions of those who recently earned a doctoral degree with focus on technology and engineering education. In the past, this group developed and assumed major roles in leading their education professions. This study reports on new doctoral graduates’ perceptions related to the focus of content taught in formalized K-12 technology …