Engineering Commons^™

Electrosensitization Assists Cell Ablation By Nanosecond Pulsed Electric Field In 3d Cultures, Claudia Muratori, Andrei G. Pakhomov, Shu Xiao, Olga N. Pakhomova

Bioelectrics Publications

Previous studies reported a delayed increase of sensitivity to electroporation (termed "electrosensitization") in mammalian cells that had been subjected to electroporation. Electrosensitization facilitated membrane permeabilization and reduced survival in cell suspensions when the electric pulse treatments were split in fractions. The present study was aimed to visualize the effect of sensitization and establish its utility for cell ablation. We used KLN 205 squamous carcinoma cells embedded in an agarose gel and cell spheroids in Matrigel. A local ablation was created by a train of 200 to 600 of 300-ns pulses (50 Hz, 300-600 V) delivered by a two-needle probe with …

The Protective Role Of Mlcp-Mediated Erm Dephosphorylation In Endotoxin-Induced Lung Injury In Vitro And In Vivo, Anita Kovacs-Kasa, Boris A. Gorshkov, Kyung-Mi Kim, Sanjiv Kumar, Stephen M. Black, David J. Fulton, Christiana Dimitropoulou, John D. Catravas, Alexander D. Verin

Bioelectrics Publications

The goal of this study was to investigate the role of MLC phosphatase (MLCP) in a LPS model of acute lung injury (ALI). We demonstrate that ectopic expression of a constitutively-active (C/A) MLCP regulatory subunit (MYPT1) attenuates the ability of LPS to increase endothelial (EC) permeability. Down-regulation of MYPT1 exacerbates LPS-induced expression of ICAM1 suggesting an anti-inflammatory role of MLCP. To determine whether MLCP contributes to LPS-induced ALI in vivo, we utilized a nanoparticle DNA delivery method to specifically target lung EC. Expression of a C/A MYPT1 reduced LPS-induced lung inflammation and vascular permeability. Further, increased expression of the …

Activation Of Dna Pattern Recognition Receptors After Plasmid Electrotransfer In Melanoma Cells And Tumors, Loree Heller, Masa Bosnjak, Katarina Znidar, Maja Cemazar

Bioelectrics Publications

(First sentence) In vivo electroporation or electrotransfer, the application of controlled electric pulses, enhances delivery of plasmid DNA to a wide variety of healthy tissues as well as tumor types.

A Dielectric Rod Antenna For Picosecond Pulse Stimulation Of Neurological Tissue, Ross A. Petrella, Karl H. Schoenbach, Shu Xiao

Bioelectrics Publications

A dielectrically loaded wideband rod antenna has been studied as a pulse delivery system to subcutaneous tissues. Simulation results applying 100-ps electrical pulse show that it allows us to generate a critical electric field for biological effects, such as brain stimulation, in the range of several centimeters. In order to reach the critical electric field for biological effects, which is similar to 20 kV/cm, at a depth of 2 cm, the input voltage needs to be 175 kV. The electric field spot size in the brain at this position is similar to 1 cm(2). Experimental studies in free space with …

Comparison Between Electropositive And Electronegative Cold Atmospheric-Pressure Plasmas: A Modelling Study, Ding X. Liu, Jia F. Li, Ai J. Yang, Xiao H. Wang, Ming Z. Rong, Michael G. Kong

Bioelectrics Publications

Cold atmospheric-pressure He + N₂ and He + O₂ plasmas are chosen as the representatives for electropositive and electronegative plasmas, of which the discharge characteristics are studied and then compared to each other by fluid models. As the increase of the impurity (N₂ or O₂) fraction from 0 to 10%, for He + N₂ plasmas the electron density and ion density increase, the spatiotemporal distributions of electron density, ion density, electron temperature and electron generation rate change a little. On contrast, for He + O₂ plasmas the electron density decreases, the ion density …

Computational Assessment Of Neural Probe And Brain Tissue Interface Under Transient Motion, Michael Polanco, Sebastian Bawab, Hangsoon Yoon

Mechanical & Aerospace Engineering Faculty Publications

The functional longevity of a neural probe is dependent upon its ability to minimize injury risk during the insertion and recording period in vivo, which could be related to motion-related strain between the probe and surrounding tissue. A series of finite element analyses was conducted to study the extent of the strain induced within the brain in an area around a neural probe. This study focuses on the transient behavior of neural probe and brain tissue interface with a viscoelastic model. Different stages of the interface from initial insertion of neural probe to full bonding of the probe by astro-glial …

Electrokinetic Phenomena In Pencil Lead-Based Microfluidics, Yashar Bashirzadeh, Venkat Maruthamuthu, Shizhi Qian

Mechanical & Aerospace Engineering Faculty Publications

Fabrication of microchannels and associated electrodes to generate electrokinetic phenomena often involves costly materials and considerable effort. In this study, we used graphite pencil-leads as low cost, disposable 3D electrodes to investigate various electrokinetic phenomena in straight cylindrical microchannels, which were themselves fabricated by using a graphite rod as the microchannel mold. Individual pencil-leads were employed as the micro-electrodes arranged along the side walls of the microchannel. Efficient electrokinetic phenomena provided by the 3D electrodes, including alternating current electroosmosis (ACEO), induced-charge electroosmosis (ICEO), and dielectrophoresis (DEP), were demonstrated by the introduced pencil-lead based microfluidic devices. The electrokinetic phenomena were characterized …

Effects Of High Voltage Nanosecond Electric Pulses On Eukaryotic Cells (In Vitro): A Systematic Review, Tina Batista Napotink, Matej Reberšek, P. Thomas Vernier, Babara Mali, Damijan Miklavčič

Bioelectrics Publications

For this systematic review, 203 published reports on effects of electroporation using nanosecond high-voltage electric pulses (nsEP) on eukaryotic cells (human, animal, plant) in vitro were analyzed. A field synopsis summarizes current published data in the field with respect to publication year, cell types, exposure configuration, and pulse duration. Published data were analyzed for effects observed in eight main target areas (plasma membrane, intracellular, apoptosis, calcium level and distribution, survival, nucleus, mitochondria, stress) and an additional 107 detailed outcomes. We statistically analyzed effects of nsEP with respect to three pulse duration groups: A: 1–10 ns, B: 11–100 ns and C: …

Electroporation By Subnanosecond Pulses, Iurii Semenov, Shu Xiao, Andrei G. Pakhomov

Bioelectrics Publications

Electropermeabilization of cell membranes by micro- and nanosecond-duration stimuli has been studied extensively, whereas effects of picosecond electric pulses (psEP) remain essentially unexplored. We utilized whole-cell patch clamp and Di-8-ANEPPS voltage-sensitive dye measurements to characterize plasma membrane effects of 500 ps stimuli in rat hippocampal neurons (RHN), NG108, and CHO cells. Even a single 500-ps pulse at 190kV/cm increased membrane conductance and depolarized cells. These effects were augmented by applying brief psEP bursts (5–125 pulses), whereas the rate of pulse delivery (8Hz–1kHz) played little role. psEP-treated cells displayed large inward current at negative membrane potentials but modest or no conductance …

Uv Light-Induced Aggregation Of Titania Submicron Particles, Can Zhou, Yashar Bashirzadeh, Timothy A. Bernadowsky Jr., Xiaoyu Zhang

Mechanical & Aerospace Engineering Faculty Publications

In this study, aggregation of TiO₂ (rutile and anatase) submicron particles in deionized (DI) water under ultra-violet (UV) light irradiation was investigated. While no aggregation was observed in the dark, rutile and anatase submicron particles started aggregating upon application of UV light and ceased aggregation in about 2 and 8.4 h, respectively. It has been demonstrated that UV light directly mitigated the particle mobility of TiO₂, resulting in a neutralization effect of the Zeta potential. It was also observed that rutile particles aggregated much faster than anatase particles under UV radiation, indicating that the Zeta potential of …

Complex System Governance For Acquisition, Joseph Bradley, Polinpapilinho Katina, Charles Keating

Engineering Management & Systems Engineering Faculty Publications

As acquisition processes have become more complex, they appear to no longer be governable by traditional approaches. Missed budgets, delayed deliveries, and expensive canceled systems appear to becoming more prevalent. Numerous investigations have been conducted attempting to elicit the factors that prevented success. Those systems that succeed in terms of usability, budget, and delivery schedule are the rarity and often become case studies themselves as we try to extract the characteristics that differentiate success from failure. A different viewpoint is to look at the acquisition system from the perspective of Complex Systems Governance (CSG). Recent developments in the field of …

Impacts Of Music On Sectional View Drawing Ability For Engineering Technology Students As Measured Through Technical Drawings, Petros J. Katsioloudis, Mildred Jones, Vukica Jovanovic

STEMPS Faculty Publications

Results from a number of studies indicate that the use of different types of music can influence cognition and behavior; however, research provides inconsistent results. Considering this, a quasi-experimental study was conducted to identify the existence of statistically significant effects on sectional view drawing ability due to the impacts of music. In particular, the study compared the use of three different types of music; classical, rock, heavy metal and whether a significant difference exists towards sectional view drawing ability, among engineering technology students. According to the results of this study it is suggested that the impact of music provides no …

Web Tools: Keeping Learners On Pace, Mickey Kosloski

STEMPS Faculty Publications

One of the greatest challenges in teaching technology and engineering is pacing. Some students grasp new technological concepts quickly, while others need repetition and may struggle to keep pace. This poses an obstacle for the technology and engineering teacher, and is particularly true when teaching students to build a website. However, there are a plethora of online tools available that can assist learners in building a website. This article identifies some of the tools that may be used in the classroom and for classroom-oriented, teacher-hosted websites. While specific examples are provided, Web search terms are denoted at the end of …

Spatio-Temporal Progression Of Cortical Activity Related To Continuous Overt And Covert Speech Production In A Reading Task, Jonathan S. Brumberg, Dean J. Krusienski, Shreya Chakrabarti, Aysegul Gunduz, Peter Brunner, Anthony L. Ritaccio, Gerwin Schalk

Electrical & Computer Engineering Faculty Publications

How the human brain plans, executes, and monitors continuous and fluent speech has remained largely elusive. For example, previous research has defined the cortical locations most important for different aspects of speech function, but has not yet yielded a definition of the temporal progression of involvement of those locations as speech progresses either overtly or covertly. In this paper, we uncovered the spatio-temporal evolution of neuronal population-level activity related to continuous overt speech, and identified those locations that shared activity characteristics across overt and covert speech. Specifically, we asked subjects to repeat continuous sentences aloud or silently while we recorded …

Backward Dijkstra Algorithms For Finding The Departure Time Based On The Specified Arrival Time For Real-Life Time-Dependent Networks, Gelareh Bakhtyar, Vi Nguyen, Mecit Cetin, Duc Nguyen

Civil & Environmental Engineering Faculty Publications

A practical transportation problem for finding the “departure” time at “all source nodes” in order to arrive at “some destination nodes” at specified time for both FIFO (i.e., First In First Out) and Non-FIFO “Dynamic ” Networks is considered in this study. Although shortest path (SP) for dynamic networks have been studied/documented by various researchers, contributions from this present work consists of a sparse matrix storage scheme for efficiently storing large scale sparse network’s connectivity, a concept of Time Delay Factor (TDF) combining with a “general piece- wise linear function” to describe the link cost as a function of time …

Evolution Of Moiré Profiles From Van Der Waals Superstructures Of Boron Nitride Nanosheets, Yunlong Liao, Wei Cao, John W. Connell, Zhongfang Chen, Yi Lin

Applied Research Center Publications

Two-dimensional (2D) van der Waals (vdW) superstructures, or vdW solids, are formed by the precise restacking of 2D nanosheet lattices, which can lead to unique physical and electronic properties that are not available in the parent nanosheets. Moiré patterns formed by the crystalline mismatch between adjacent nanosheets are the most direct features for vdW superstructures under microscopic imaging. In this article, transmission electron microscopy (TEM) observation of hexagonal Moiré patterns with unusually large micrometer-sized lateral areas (up to similar to 1μm² and periodicities (up to similar to 50 nm) from restacking of liquid exfoliated hexagonal boron nitride nanosheets (BNNSs) …

New Frontiers In Chemical Energy And Environmental Engineering, Srinath Suranani, Sandeep Kumar, Sundergopal Sridhar

Civil & Environmental Engineering Faculty Publications

(First paragraph) Energy is one of the major building blocks of modern society. Industries are attributed to be the main source of environmental pollution. The problems associated with the energy and environment have now become the subject of international debate. Engineers play vital role in devising environmental pollution mitigating techniques and developing sustainable energy technologies.

Radio-Frequency Plasma Polymerized Biodegradable Carrier For In Vivo Release Of Cis-Platinum, Sudhir Bhatt, Fatemeh Valamanesh, Jerome Pulpytel, Rea Lo Dico, Aliby Baiyukha, Iman Al-Dybiat, Marc Pocard, Farzaneh Arefi-Khonsari, Massoud Mirshahi

Bioelectrics Publications

A low pressure plasma process based on plasma deposition has been used to develop a drug delivery strategy. In this study, a drug delivery system based on different layers of plasma co-polymerized Poly ε-caprolactone-Polyethylene glycol (PCL-PEG) co-polymers was deposited on biocompatible substrates. Cis-platinum (118 μgm/cm²) was used as an anti-cancer drug and incorporated for local delivery of the chemotherapeutic agent. The co-polymer layers and their interaction with cancer cells were analyzed by scanning electron microscopy. Our study showed that the plasma-PCL-PEG coated cellophane membranes, in which the drug, was included did not modify the flexibility and appearance of …

Aqueous Reactive Species Induced By A Surface Air Discharge: Heterogenous Mass Transfer And Liquid Chemistry Pathways, D. X. Liu, Z. C. Liu, C. Chen, A. J. Yang, D. Li, M. Z. Rong, H. L. Chen, M. G. Kong

Bioelectrics Publications

Plasma-liquid interaction is a critical area of plasma science and a knowledge bottleneck for many promising applications. In this paper, the interaction between a surface air discharge and its downstream sample of deionized water is studied with a system-level computational model, which has previously reached good agreement with experimental results. Our computational results reveal that the plasma-induced aqueous species are mainly H+, nitrate, nitrite, H2O2 and O-3. In addition, various short-lived aqueous species are also induced, regardless whether they are generated in the gas phase first. The production/loss pathways for aqueous species are quantified for an air gap width ranging …

First-Year Project Experience In Aerospace: Apogee Determination Of Model Rockets With Explicit Consideration Of Drag Effect, Hüseyin Sarper, Drew Landman, Linda Vahala

Electrical & Computer Engineering Faculty Publications

This paper describes a student team project using model rockets and engines to learn engineering solution methods for determining the apogee of model rocket when the drag effect is considered explicitly instead of estimating its effect later. Model rocketry is a powerful tool for instructors who wish to incorporate science, engineering, and mathematics into a fun, engaging, and challenging activity for the students. The apogee can be determined using a number of distinct methods: trigonometry, onboard altimeters, analytical calculations, and simulation. This paper emphasizes numerical analytical solution using spreadsheet programming instead of a full analytical solution that requires higher mathematics. …

Application Of Visual Cues On 3d Dynamic Visualizations For Engineering Technology Students And Effects On Spatial Visualization Ability: A Quasi-Experimental Study, Petros Katsioloudis, Vukica Jovanovic, Mildred Jones

STEMPS Faculty Publications

Several theorists believe that different types of visual cues influence cognition and behavior through learned associations; however, research provides inconsistent results. Considering this, a quasi-experimental study was done to determine if there are significant positive effects of visual cues (color blue) and to identify if a positive increase in spatial visualization ability for students in engineering technology courses is observed. According to the results of this study it is suggested that the use of the specific visual cue (color blue) provides no statistically significant higher scores versus the treatment that did not utilize any visual cues.

Impact Of Optimally Minimizing Delay Times On Safety At Signalized Intersections In Urban Areas, Case Study: The City Of Virginia Beach, Eugene Vida Maina, Albert Forde, R. Michael Robinson

VMASC Publications

Optimally minimizing delay times at signalized intersections can significantly improve both traffic flow and safety. However, most traffic flow optimizing tools do not measure the effect on safety. This study uses nonlinear programming (NLP) algorithms to optimally minimize delay times and employs both Safety performance functions (SPFs) and empirical Bayes (EB) before-after methodology to measure the impact on safety presented as a Crash Modification Factor (CMF). A crash modification factor (CMF) is a multiplicative factor used by transportation practitioners to compute the expected number of crashes at specific study site(s) after a countermeasure has been proposed or is implemented. Using …

The Role Of Microbial Exopolymers In Determining The Fate Of Oil And Chemical Dispersants In The Ocean, Antonietta Quigg, Uta Passow, Wei-Chun Chin, Chen Xu, Shawn Doyle, Laura Bretherton, Manoj Kamalanathan, Alicia K. Williams, Jason B. Sylvan, Zoe V. Finkel, Anthony H. Knap, Kathleen A. Schwehr, Saijin Zhang, Luni Sun, Terry L. Wade, Wassim Obeid, Patrick G. Hatcher, Peter H. Santschi

Chemistry & Biochemistry Faculty Publications

The production of extracellular polymeric substances (EPS) by planktonic microbes can influence the fate of oil and chemical dispersants in the ocean through emulsification, degradation, dispersion, aggregation, and/or sedimentation. In turn, microbial community structure and function, including the production and character of EPS, is influenced by the concentration and chemical composition of oil and chemical dispersants. For example, the production of marine oil snow and its sedimentation and flocculent accumulation to the seafloor were observed on an expansive scale after the Deepwater Horizon oil spill in the Northern Gulf of Mexico in 2010, but little is known about the underlying …

Anticancer, Biophysical And Computational Investigations Of Half-Sandwich Ruthenium(Ii) Thiosemicarbazone Complexes: The Effect Of Arene Versus Thiacrown Face-Cap, Floyd A. Beckford, Alyssa Stott, P. Canisius Mbarushimana, Marc-Andre Leblanc, Kinsey Hall, Samantha Smith, Jimmie L. Bullock, Dennis J. Houghton, Alvin A. Holder, Nikolay Gerasimchuk, Antonio Gonzalez-Sarrías

Chemistry & Biochemistry Faculty Publications

A series of half-sandwich ruthenium complexes, two containing an arene face-cap and the other a thiacrown ether face-cap were synthesized to investigate the necessity of the arene for anticancer activity in this class of compounds. The complexes are formulated as [(h⁶-p-cymene)Ru(dmabTSC)Cl]PF₆, [(h⁶-benzene)Ru(dmabTSC)Cl]PF₆ (arene complexes), and [([9]aneS₃(dmabTSC)Cl]PF₆ (dmabTSC = dimethylaminobenzaldehye thiosemicarbazone). It was observed that none of the complexes showed good anticancer activity in vitro against HCT-116 and Caco-2 (colon adenocarcinoma) cells. All three complexes can bind strongly to calf-thymus DNA with binding constants on the order of 10 …

Characterization Of Biochars Produced From Peanut Hulls And Pine Wood With Different Pyrolysis Conditions, James W. Lee, Bob Hawkins, Michelle K. Kidder, Barbara R. Evans, A. C. Buchanan, Danny Day

Chemistry & Biochemistry Faculty Publications

Background

Application of modern biomass pyrolysis methods for production of biofuels and biochar is potentially a significant approach to enable global carbon capture and sequestration. To realize this potential, it is essential to develop methods that produce biochar with the characteristics needed for effective soil amendment.

Methods

Biochar materials were produced from peanut hulls and pine wood with different pyrolysis conditions, then characterized by cation exchange (CEC) capacity assays, nitrogen adsorption–desorption isotherm measurements, micro/nanostructural imaging, infrared spectra and elemental analyses.

Results

Under a standard assay condition of pH 8.5, the CEC values of the peanut hull-derived biochar materials, ranging from …

Efficient Generalized Inverse For Solving Simultaneous Linear Equations, S. Kadiam Bose, D. T. Nguyen

Civil & Environmental Engineering Faculty Publications

Solving large scale system of Simultaneous Linear Equations (SLE) has been (and continue to be) a major challenging problem for many real-world engineering and science applications. Solving SLE with singular coefficient matrices arises from various engineering and sciences applications [1]-[6]. In this paper, efficient numerical procedures for finding the generalized (or pseudo) inverse of a general (square/rectangle, symmetrical/unsymmetrical, non-singular/singular) matrix and solving systems of Simultaneous Linear Equations (SLE) are formulated and explained. The developed procedures and its associated computer software (under MATLAB [7] computer environment) have been based on "special Cholesky factorization schemes" (for a singular matrix). Test matrices from …

Lateral-Torsional Buckling Of Frp I-Section Beams, Mojtaba B. Sirjani, Zia Razzaq

Civil & Environmental Engineering Faculty Publications

This paper presents the outcome of an experimental and theoretical investigation into the load-carrying capacity of Fiber Reinforced Polymer (FRP) I-section beams subjected to four-point loading. The overall lateral-torsional buckling, web and flange local buckling as well as material rupture load estimates are also made using the American Society of Civil Engineers Load and Resistance Factor Design (ASCE-LRFD) Pre-Standard for FRP Structures. Lateral-torsional buckling failure mode is found to govern for each of the beams studied. The study also revealed that the height of applied loads relative to the shear center has a very significant influence on lateral-torsional buckling load …

Elasto-Plastic Transient Dynamic Response Of Tubular Section Steel Cantilever Beam Under Impact Loading, Alial Aloosi, Zia Razzaq

Civil & Environmental Engineering Faculty Publications

This paper presents the outcome of an experimental and theoretical investigation into the loadcarrying capacity of Fiber Reinforced Polymer (FRP) I-section beams subjected to four-point loading. The overall lateral-torsional buckling, web and flange local buckling as well as material rupture load estimates are also made using the American Society of Civil Engineers#x2019; Load and Resistance Factor Design (ASCELRFD) Pre-Standard for FRP Structures. Lateral-torsional buckling failure mode is found to govern for each of the beams studied. The study also revealed that the height of applied loads relative to the shear center has a very significant influence on lateral-torsional buckling load …

Transformation Model With Constraints For High Accuracy Of 2d-3d Building Registration In Aerial Imagery, Guoqing Zhou, Qingli Luo, Wenhan Xie, Tao Yue, Jingjin Huang, Yuzhong Shen

Computational Modeling & Simulation Engineering Faculty Publications

This paper proposes a novel rigorous transformation model for 2D-3D registration to address the difficult problem of obtaining a sufficient number of well-distributed ground control points (GCPs) in urban areas with tall buildings. The proposed model applies two types of geometric constraints, co-planarity and perpendicularity, to the conventional photogrammetric collinearity model. Both types of geometric information are directly obtained from geometric building structures, with which the geometric constraints are automatically created and combined into the conventional transformation model. A test field located in downtown Denver, Colorado, is used to evaluate the accuracy and reliability of the proposed method. The comparison …

A Microfluidic-Based Tactile Sensor For Palpating Mice Tumor Tissues, Yichao Yang, Garett Johnson, Dean Krusienski, Siqi Guo, Cheng Lin, Zhili Hao

Mechanical & Aerospace Engineering Faculty Publications

In light of the need of tissue palpation for Robotics-assisted Minimally Invasive Surgery (RMIS), this paper presents a microfluidic-based tactile sensor for palpating mice tissues for tumor localization. The core of the sensor is a 3x3 sensing-plate/transducer array built into a single polydimethylsiloxane (PDMS) microstructure, with a transducer spacing of 3.75mmx1.5mm. Mounted on a robot, the sensor is pressed against a tissue region with a pre-defined indentation depth pattern, and consequently the stiffness distribution across the tissue region translates to the deflection distribution of the sensing-plate array and is captured by the transducer array underneath as resistance changes. Thus, the …