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2021

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Full-Text Articles in Engineering

The Impact Of Unequal Processing Time Variability On Reliable And Unreliable Merging Line Performance, Rodrigo Romero-Silva, Sabry Shaaban, Erika Marsillac, Zouhair Laaarraf Jan 2021

The Impact Of Unequal Processing Time Variability On Reliable And Unreliable Merging Line Performance, Rodrigo Romero-Silva, Sabry Shaaban, Erika Marsillac, Zouhair Laaarraf

Information Technology & Decision Sciences Faculty Publications

Research on merging lines is expanding as their use grows significantly in the contexts of remanufacturing, reverse logistics and developing economies. This article is the first to study the behavior of unpaced, reliable, and unreliable merging assembly lines that are deliberately unbalanced with respect to their coefficients of variation (CV). Conducting a series of simulation runs with varying line lengths, buffer storage capacities and unbalanced CV patterns delivers intriguing results. For both reliable and unreliable lines, the best pattern for generating higher throughput is found to be a balanced configuration (equal CVs along both parallel lines), except for unreliable lines …


Inventions Of Scientists, Engineers And Specialists From Different Countries In The Area Of Nanotechnologies. Part Iv, Leonid A. Ivanov, Li Da Xu, Zhanna V. Pisarenko, Cahn T. Nguyen, Svetlana R. Muminova Jan 2021

Inventions Of Scientists, Engineers And Specialists From Different Countries In The Area Of Nanotechnologies. Part Iv, Leonid A. Ivanov, Li Da Xu, Zhanna V. Pisarenko, Cahn T. Nguyen, Svetlana R. Muminova

Information Technology & Decision Sciences Faculty Publications

Introduction. Advanced technologies impress people's imagination demonstrating the latest achievements (materials, methods, systems, technologies, devices etc.) that dramatically change the world. This, first of all, concerns nanotechnological inventions designed by scientists, engineers and specialists from different countries. Main part. The paper briefly reviews inventions made by scientists, engineers and specialists from different countries: Russia, USA, China, Belarus, Great Britain, Vietnam, Denmark, the Kyrgyz Republic. The application of the results of scientists', engineers' and specialists' investigations, including inventions in the area of nanotechnology and nanomaterials allow achieving significant efficiency in construction, house and communal service, related sectors of economy. For example, …


Generic Design Methodology For Smart Manufacturing Systems From A Practical Perspective, Part I—Digital Triad Concept And Its Application As A System Reference Model, Zhuming Bi, Wen-Jun Zhang, Chong Wu, Chaomin Luo, Lida Xu Jan 2021

Generic Design Methodology For Smart Manufacturing Systems From A Practical Perspective, Part I—Digital Triad Concept And Its Application As A System Reference Model, Zhuming Bi, Wen-Jun Zhang, Chong Wu, Chaomin Luo, Lida Xu

Information Technology & Decision Sciences Faculty Publications

Rapidly developed information technologies (IT) have continuously empowered manufacturing systems and accelerated the evolution of manufacturing system paradigms, and smart manufacturing (SM) has become one of the most promising paradigms. The study of SM has attracted a great deal of attention for researchers in academia and practitioners in industry. However, an obvious fact is that people with different backgrounds have different expectations for SM, and this has led to high diversity, ambiguity, and inconsistency in terms of definitions, reference models, performance matrices, and system design methodologies. It has been found that the state of the art SM research is limited …


Safety And Operations Of Urban Arterials Incorporating The Context Classification System, Nada Mahmoud Jan 2021

Safety And Operations Of Urban Arterials Incorporating The Context Classification System, Nada Mahmoud

Electronic Theses and Dissertations, 2020-2023

Urban arterials connect multiple areas in the city and encourage non-motorist activities. Hence, the safety and operations on urban arterials is vital as they improve the mobility of daily commuters and road users. This research aims to facilitate traffic operations on urban arterials by proposing multiple mythological approaches to estimate and predict turning movement counts at signalized intersections using traffic data from adjacent intersections. Further, it aims to improve the safety by developing crash prediction models, identifying the hotspots for multiple crash types, and indicating the factors contributing to operating speed as well as non-motorist crashes. The analyses included tuning, …


Laser-Microdrop Interactions In Nanoparticle Deposition On Solid Substrates, Tianyi Li Jan 2021

Laser-Microdrop Interactions In Nanoparticle Deposition On Solid Substrates, Tianyi Li

Electronic Theses and Dissertations, 2020-2023

Nanoparticle suspensions are utilized for depositing thin films on solid substrates by a process called nano electrospray laser deposition. In this research, three deposition methods, contact liquid line laser printing, nano-electrospray laser sintering and evaporative optical Marangoni convection are investigated experimentally and analytically. Thin silver lines are printed on indium tin oxide-coated silicon substrates by dispensing silver nanoparticle suspension with a micropipe of inner diameter 51µm and subsequently sintering the nanoparticles with a CO2 laser beam of Bessel intensity profile. The deposited silver lines of 65µm width and 1µm height have good resistivity which can be used to manufacture silver …


การเพิ่มประสิทธิภาพการจัดการพลาสติกรีไซเคิลโดยใช้ระบบ Gis กรณีศึกษา: ชุมชนในจังหวัดระยอง, ชยานนท์ เทียนธนานุรักษ์ Jan 2021

การเพิ่มประสิทธิภาพการจัดการพลาสติกรีไซเคิลโดยใช้ระบบ Gis กรณีศึกษา: ชุมชนในจังหวัดระยอง, ชยานนท์ เทียนธนานุรักษ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มีวัตถุประสงค์เพื่อศึกษาการจัดการขยะบรรจุภัณฑ์พลาสติกระดับชุมชนในพื้นที่จังหวัดระยองและสร้างแบบจำลองการแลกเปลี่ยนข้อมูลการรับซื้อขายขยะพลาสติกโดยใช้ระบบสารสนเทศทางภูมิศาสตร์ (Geographic information system; GIS) เพื่อช่วยในการจัดการขยะพลาสติกอย่างมีประสิทธิภาพและหมุนเวียนกลับมาใช้ประโยชน์สูงสุดตามหลักเศรษฐกิจหมุนเวียน ด้วยวิธีการสำรวจและรวบรวมข้อมูลชนิด ปริมาณขยะพลาสติกและที่ตั้งร้านรับซื้อในพื้นที่กรณีศึกษา 3 แห่ง ได้แก่ เทศบาลนครระยอง หมู่4 เทศบาลทับมา และชุมชนบ้านเอื้ออาทรวังหว้า ผลการวิจัยพบว่าการจัดการขยะพลาสติกในชุมชนกรณีศึกษาทั้ง 3 แห่งยังขาดความเชื่อมโยงในการจัดการขยะพลาสติกของผู้มีส่วนได้เสียตลอดห่วงโซ่คุณค่า และยังไม่ทราบช่องทางติดต่อการซื้อขายหรือตำแหน่งที่ตั้งของร้านรับซื้อหรือโรงงาน ดังนั้นงานวิจัยนี้ช่วยให้ทราบถึงพิกัดร้านรับซื้อขยะพลาสติกประเภทต่าง ๆ ในชุมชนกรณีศึกษาโดยใช้ระบบ GIS และเสนอแบบจำลองการแลกเปลี่ยนข้อมูลการรับซื้อขายขยะพลาสติกในจังหวัดระยอง ซึ่งพบว่าปัจจุบันเส้นทางการขนส่งขยะพลาสติกของชุมชนกรณีศึกษาทั้ง 3 แห่ง ของเทศบาลนครระยอง ชุมชนหมู่4 เทศบาลทับมาและชุมชนบ้านเอื้ออาทรวังหว้าจากธนาคารขยะไปยังร้านรับซื้อขวด/ถุงพลาสติก และส่งต่อไปโรงงานรีไซเคิลมีระยะทางขนส่งเท่ากับ 430.55 , 286.91 และ 458.51 กิโลเมตร ตามลำดับ จึงนำเสนอทางเลือกการเปลี่ยนร้านรับซื้อขวด/ถุงพลาสติก และโรงงานรีไซเคิล พบว่าสามารถลดระยะทางขนส่งลงเท่ากับ 165.58, 149.65 และ 348.81 กิโลเมตร ตามลำดับ คิดเป็นร้อยละ 61.54, 47.84 และ 23.93 ตามลำดับ สามารถลดการปล่อยก๊าซเรือนกระจกลงร้อยละ 92.94 , 83.85 และ 77.35 ตามลำดับ ดังนั้นหากสามารถเปลี่ยนมาใช้เส้นทางการขนส่งที่เสนอแนะได้จะสามารถช่วยลดการใช้เชื้อเพลิงและการปล่อยก๊าซเรือนกระจกสู่ชั้นบรรยากาศได้


A Comparison Of Artificial Neural Networks And The Statistical Methods In Predicting Mba Student’S Academic Performance, Ojoung Kwon, Harry Hui Xia, Serin Zhang Jan 2021

A Comparison Of Artificial Neural Networks And The Statistical Methods In Predicting Mba Student’S Academic Performance, Ojoung Kwon, Harry Hui Xia, Serin Zhang

Journal of International Technology and Information Management

MBA has become one of the most popular and vital professional degrees internationally. The MBA program admission process’s essential task is to choose the best analysis tools to accurately predict applicants’ academic performance potential based on the evaluation criteria in making admission decisions. Prior research finds that the Graduate Management Admission Test (GMAT) and undergraduate grade point average (UGPA) are common predictors of MBA academic performance indicated by graduate grade point average (GGPA). Using a sample of 250 MBA students enrolled in a state university with AACSB accreditation from Fall 2010 to Fall 2017, we test and compare the effectiveness …


An Integrated View Of Knowledge Management Enablers, Components, And Benefits: Comprehensive Literature Review, Shuaibu Hassan Usman, Jigish Zaveri, Aminu Hamza Jan 2021

An Integrated View Of Knowledge Management Enablers, Components, And Benefits: Comprehensive Literature Review, Shuaibu Hassan Usman, Jigish Zaveri, Aminu Hamza

Journal of International Technology and Information Management

The key to success in the 21st century, knowledge-based economy, will be the effective and efficient management of knowledge. Knowledge Management (KM) has a direct impact on organizational success. KM in a knowledge-based economy entails growth, value, and improving living standards through knowledge creation, storage, and dissemination. This study aims to integrate KM enablers, components, and benefits into a single view through a comprehensive literature search. The integrative view of these three factors would facilitate the understanding of KM initiatives within organizations. This paper performs a comprehensive literature review to explain the KM enablers, components, and benefits. From the …


Unobtrusive Assessment Of Student Engagement Levels In Online Classroom Environment Using Emotion Analysis, Sasirekha Anbusegaran Jan 2021

Unobtrusive Assessment Of Student Engagement Levels In Online Classroom Environment Using Emotion Analysis, Sasirekha Anbusegaran

College of Graduate Studies: Theses & Dissertations

Measuring student engagement has emerged as a significant factor in the process of learning and a good indicator of the knowledge retention capacity of the student. As synchronous online classes have become more prevalent in recent years, gauging a student's attention level is more critical in validating the progress of every student in an online classroom environment. This paper details the study on profiling the student attentiveness to different gradients of engagement level using multiple machine learning models. Results from the high accuracy model and the confidence score obtained from the cloud-based computer vision platform - Amazon Rekognition were then …


A Techno-Economic Comparison Of Battery Electric And Hydrogen Fuel-Cell Transit Bus Fleet Options For Humboldt County, California, Aditya S. Kushwah Mr. Jan 2021

A Techno-Economic Comparison Of Battery Electric And Hydrogen Fuel-Cell Transit Bus Fleet Options For Humboldt County, California, Aditya S. Kushwah Mr.

Cal Poly Humboldt theses and projects

This study analyzes the techno-economic feasibility of converting the conventional transit bus fleet of the Humboldt Transit Authority (HTA) into a battery-electric or a hydrogen-fueled bus fleet. The study identifies which of these technologies represents the more economically viable investment for HTA by analyzing the costs and benefits associated with each pathway. Both pathways involve zero-emission or low-emission technologies.

The study outcomes suggest that the conversion of the HTA’s current conventional fleet to an electric fleet is more feasible than conversion to a hydrogen fuel cell bus fleet. The total discounted cost (3% rate) of converting the 21-bus conventional fleet …


2-Ns Electrostimulation Of Ca2+ Influx Into Chromaffin Cells: Rapid Modulation By Field Reversal, Josette Zaklit, Gale L. Craviso, Normand Leblanc, P. Thomas Vernier, Esin B. Sözer Jan 2021

2-Ns Electrostimulation Of Ca2+ Influx Into Chromaffin Cells: Rapid Modulation By Field Reversal, Josette Zaklit, Gale L. Craviso, Normand Leblanc, P. Thomas Vernier, Esin B. Sözer

Bioelectrics Publications

Cellular effects of nanosecond pulsed electric field exposures can be attenuated by an electric field reversal, a phenomenon called bipolar pulse cancellation. Our investigations of this phenomenon in neuroendocrine adrenal chromaffin cells show that a single 2 ns, 16 MV/m unipolar pulse elicited a rapid, transient rise in intracellular Ca2+ levels due to Ca2+ influx through voltage-gated calcium channels. The response was eliminated by a 2 ns bipolar pulse with positive and negative phases of equal duration and amplitude, and fully restored (unipolar-equivalent response) when the delay between each phase of the bipolar pulse was 30 ns. Longer …


The Antitumor Effects Of Plasma-Activated Saline On Muscle-Invasive Bladder Cancer Cells In Vitro And In Vivo Demonstrate Its Feasibility As A Potential Therapeutic Approach, Hao Zhang, Jishen Zhang, Bo Guo, Hailan Chen, Dehui Xu, Michael G. Kong Jan 2021

The Antitumor Effects Of Plasma-Activated Saline On Muscle-Invasive Bladder Cancer Cells In Vitro And In Vivo Demonstrate Its Feasibility As A Potential Therapeutic Approach, Hao Zhang, Jishen Zhang, Bo Guo, Hailan Chen, Dehui Xu, Michael G. Kong

Bioelectrics Publications

Muscle-invasive bladder cancer (MIBC) is a fast-growing and aggressive malignant tumor in urinary system. Since chemotherapy and immunotherapy are only useable with a few MIBC patients, the clinical treatment of MIBC still faces challenges. Here, we examined the feasibility of plasma-activated saline (PAS) as a fledgling therapeutic strategy for MIBC treatment. Our data showed that plasma irradiation could generate a variety of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in saline. In vivo tests revealed that pericarcinomatous tissue injection with PAS was effective at preventing subcutaneous bladder tumor growth, with no side effects to the visceral organs after …


Fluid Model Of Plasma-Liquid Interaction: The Effect Of Interfacial Boundary Conditions And Henry's Law Constants, Yifan Liu, Dingxin Liu, Jishen Zhang, Bowen Sun, Santu Luo, Hao Zhang, Li Guo, Mingzhe Rong, Michael G. Kong Jan 2021

Fluid Model Of Plasma-Liquid Interaction: The Effect Of Interfacial Boundary Conditions And Henry's Law Constants, Yifan Liu, Dingxin Liu, Jishen Zhang, Bowen Sun, Santu Luo, Hao Zhang, Li Guo, Mingzhe Rong, Michael G. Kong

Bioelectrics Publications

Plasma–liquid interaction is a critical area of plasma science, mainly because much remains unknown about the physicochemical processes occurring at the plasma–liquid interface. Besides a lot of experimental studies toward the interaction, a few fluid models have also been reported in recent years. However, the interfacial boundary conditions in the models are different and the Henry's law constants therein are uncertain; hence, the accuracy and robustness of the simulation results are doubtable. In view of this, three 1D fluid models are developed for the interaction between a plasma jet and deionized water, each of which has a unique interfacial boundary …


Comprehensive Collagen Crosslinking Comparison Of Microfluidic Wet-Extruded Microfibers For Bioactive Surgical Suture Development, Amrita Dasgupta, Nardos Sori, Stella Petrova, Yas Maghdouri-White, Nick Thayer, Nathan Kemper, Seth Polk, Delaney Leathers, Kelly Coughenour, Jake Dascoli, Riya Palikonda, Connor Donahue, Anna A. Bulysheva, Michael P. Francis Jan 2021

Comprehensive Collagen Crosslinking Comparison Of Microfluidic Wet-Extruded Microfibers For Bioactive Surgical Suture Development, Amrita Dasgupta, Nardos Sori, Stella Petrova, Yas Maghdouri-White, Nick Thayer, Nathan Kemper, Seth Polk, Delaney Leathers, Kelly Coughenour, Jake Dascoli, Riya Palikonda, Connor Donahue, Anna A. Bulysheva, Michael P. Francis

Bioelectrics Publications

Collagen microfiber-based constructs have garnered considerable attention for ligament, tendon, and other soft tissue repairs, yet with limited clinical translation due to strength, biocompatibility, scalable manufacturing, and other challenges. Crosslinking collagen fibers improves mechanical properties; however, questions remain regarding optimal crosslinking chemistries, biocompatibility, biodegradation, long-term stability, and potential for biotextile assemble at scale, limiting their clinical usefulness. Here, we assessed over 50 different crosslinking chemistries on microfluidic wet-extruded collagen microfibers made with clinically relevant collagen to optimize collagen fibers as a biotextile yarn for suture or other medical device manufacture. The endogenous collagen crosslinker, glyoxal, provides extraordinary fiber ultimate tensile …


Cold Atmospheric-Pressure Plasma Caused Protein Damage In Methicillin-Resistant Staphylococcus Aureus Cells In Biofilms, Li Guo, Lu Yang, Yu Qi, Gulimire Niyazi, Lingling Huang, Lu Gou, Zifeng Wang, Lei Zhang, Dingxin Liu, Xiaohua Wang, Hailan Chen, Michael G. Kong Jan 2021

Cold Atmospheric-Pressure Plasma Caused Protein Damage In Methicillin-Resistant Staphylococcus Aureus Cells In Biofilms, Li Guo, Lu Yang, Yu Qi, Gulimire Niyazi, Lingling Huang, Lu Gou, Zifeng Wang, Lei Zhang, Dingxin Liu, Xiaohua Wang, Hailan Chen, Michael G. Kong

Bioelectrics Publications

Biofilms formed by multidrug-resistant bacteria are a major cause of hospital-acquired infections. Cold atmospheric-pressure plasma (CAP) is attractive for sterilization, especially to disrupt biofilms formed by multidrug-resistant bacteria. However, the underlying molecular mechanism is not clear. In this study, CAP effectively reduced the living cells in the biofilms formed by methicillin-resistant Staphylococcus aureus, and 6 min treatment with CAP reduced the S. aureus cells in biofilms by 3.5 log10. The treatment with CAP caused the polymerization of SaFtsZ and SaClpP proteins in the S. aureus cells of the biofilms. In vitro analysis demonstrated that recombinant SaFtsZ lost …


Cardioporation Enhances Myocardial Gene Expression In Rat Heart, Carly Boye, Sezgi Arpag, Nina Burcus, Cathryn Lundberg, Scott Declemente, Richard Heller, Michael Francis, Anna Bulysheva Jan 2021

Cardioporation Enhances Myocardial Gene Expression In Rat Heart, Carly Boye, Sezgi Arpag, Nina Burcus, Cathryn Lundberg, Scott Declemente, Richard Heller, Michael Francis, Anna Bulysheva

Bioelectrics Publications

Damage from myocardial infarction (MI) and subsequent heart failure are serious public health concerns. Current clinical treatments and therapies to treat MI damage largely do not address the regeneration of cardiomyocytes. In a previous study, we established that it is possible to promote regeneration of cardiac muscle with vascular endothelial growth factor B gene delivery directly to the ischemic myocardium. In the current study we aim to optimize cardioporation parameters to increase expression efficiency by varying electrode configuration, applied voltage, pulse length, and plasmid vector size. By using a surface monopolar electrode, optimized pulsing conditions and reducing vector size, we …


The Hsp90 Inhibitor, Auy-922, Protects And Repairs Human Lung Microvascular Endothelial Cells From Hydrochloric Acid-Induced Endothelial Barrier Dysfunction, Ruben M.L. Colunga Biancatelli, Pavel Solopov, Betsy Gregory, John D. Catravas Jan 2021

The Hsp90 Inhibitor, Auy-922, Protects And Repairs Human Lung Microvascular Endothelial Cells From Hydrochloric Acid-Induced Endothelial Barrier Dysfunction, Ruben M.L. Colunga Biancatelli, Pavel Solopov, Betsy Gregory, John D. Catravas

Bioelectrics Publications

Exposure to hydrochloric acid (HCl) leads acutely to asthma-like symptoms, acute respiratory distress syndrome (ARDS), including compromised alveolo-capillary barrier, and respiratory failure. To better understand the direct effects of HCl on pulmonary endothelial function, we studied the characteristics of HCl-induced endothelial barrier dysfunction in primary cultures of human lung microvascular endothelial cells (HLMVEC), defined the involved molecular pathways, and tested the potentially beneficial effects of Heat Shock Protein 90 (HSP90) inhibitors. HCl impaired barrier function in a time- and concentration-dependent manner and was associated with activation of Protein Kinase B (AKT), Ras homolog family member A (RhoA) and myosin light …


Moderate Heat-Assisted Gene Electrotransfer As A Potential Delivery Approach For Protein Replacement Therapy Through The Skin, Chelsea Edelblute, Cathryn Mangiamele, Richard Heller Jan 2021

Moderate Heat-Assisted Gene Electrotransfer As A Potential Delivery Approach For Protein Replacement Therapy Through The Skin, Chelsea Edelblute, Cathryn Mangiamele, Richard Heller

Bioelectrics Publications

Gene-based approaches for protein replacement therapies have the potential to reduce the number of administrations. Our previous work demonstrated that expression could be enhanced and/or the applied voltage reduced by preheating the tissue prior to pulse administration. In the current study, we utilized our 16-pin multi-electrode array (MEA) and incorporated nine optical fibers, connected to an infrared laser, between each set of four electrodes to heat the tissue to 43 °C. For proof of principle, a guinea pig model was used to test delivery of reporter genes. We observed that when the skin was preheated, it was possible to achieve …


Moderate Heat-Assisted Gene Electrotransfer For Cutaneous Delivery Of A Dna Vaccine Against Hepatitis B Virus, Chelsea Edelblute, Cathryn Mangiamele, Richard Heller Jan 2021

Moderate Heat-Assisted Gene Electrotransfer For Cutaneous Delivery Of A Dna Vaccine Against Hepatitis B Virus, Chelsea Edelblute, Cathryn Mangiamele, Richard Heller

Bioelectrics Publications

An estimated 350 million people are living with chronic Hepatitis B virus (HBV) worldwide. Preventative HBV vaccination in infants has reduced the disease burden; however, insufficient immunization programs and access obstacles leave vulnerable populations at risk for infection in endemic regions. Gene electrotransfer (GET) using a noninvasive multielectrode array (MEA) provides an alternative platform for DNA vaccination in the skin. DNA vaccines are nonlive and nonreplicating and temperature stable unlike their counterparts. In addition, their simple engineering allows them to be manufactured quickly at a low cost. In the current work, we present the combination of GET and moderate heating …


Stobe Photography Mapping Of Cell Membrane Potential With Nanosecond Resolution, Allen S. Kiester, Bennett L. Ibey, Zachary N. Coker, Andrei G. Pakhomov, Joel N. Bixler Jan 2021

Stobe Photography Mapping Of Cell Membrane Potential With Nanosecond Resolution, Allen S. Kiester, Bennett L. Ibey, Zachary N. Coker, Andrei G. Pakhomov, Joel N. Bixler

Bioelectrics Publications

The ability to directly observe membrane potential charging dynamics across a full microscopic field of view is vital for understanding interactions between a biological system and a given electrical stimulus. Accurate empirical knowledge of cell membrane electrodynamics will enable validation of fundamental hypotheses posited by the single shell model, which includes the degree of voltage change across a membrane and cellular sensitivity to external electric field non-uniformity and directionality. To this end, we have developed a high-speed strobe microscopy system with a time resolution of ~ 6 ns that allows us to acquire time-sequential data for temporally repeatable events (non-injurious …


Electroporation Safety Factor Of 300 Nanosecond And 10 Millisecond Defibrillation In Langendorff-Perfused Rabbit Hearts, Johanna U. Neuber, Andrei G. Pakhomov, Christian W. Zemlin Jan 2021

Electroporation Safety Factor Of 300 Nanosecond And 10 Millisecond Defibrillation In Langendorff-Perfused Rabbit Hearts, Johanna U. Neuber, Andrei G. Pakhomov, Christian W. Zemlin

Bioelectrics Publications

Aims

Recently, a new defibrillation modality using nanosecond pulses was shown to be effective at much lower energies than conventional 10 millisecond monophasic shocks in ex vivo experiments. Here we compare the safety factors of 300 nanosecond and 10 millisecond shocks to assess the safety of nanosecond defibrillation.

Methods and results

The safety factor, i.e. the ratio of median effective doses (ED50) for electroporative damage and defibrillation, was assessed for nanosecond and conventional (millisecond) defibrillation shocks in Langendorff-perfused New Zealand white rabbit hearts. In order to allow for multiple shock applications in a single heart, a pair of needle electrodes …


Connexin Hemichannel Activation By S-Nitrosoglutathione Synergizes Strongly With Photodynamic Therapy Potentiating Anti-Tumor Bystander Killing, Chiara Nardin, Chiara Peres, Sabrina Putti, Tiziana Orsini, Claudia Colussi, Flavia Mazzarda, Marcello Raspa, Ferdinando Scavizzi, Anna Maria Salvatore, Francesco Chiani, Abraham Tettey-Matey, Yuanyuan Kuang, Guang Yang, Mauricio A. Retamal, Fabio Mammano Jan 2021

Connexin Hemichannel Activation By S-Nitrosoglutathione Synergizes Strongly With Photodynamic Therapy Potentiating Anti-Tumor Bystander Killing, Chiara Nardin, Chiara Peres, Sabrina Putti, Tiziana Orsini, Claudia Colussi, Flavia Mazzarda, Marcello Raspa, Ferdinando Scavizzi, Anna Maria Salvatore, Francesco Chiani, Abraham Tettey-Matey, Yuanyuan Kuang, Guang Yang, Mauricio A. Retamal, Fabio Mammano

Bioelectrics Publications

In this study, we used B16-F10 cells grown in the dorsal skinfold chamber (DSC) preparation that allowed us to gain optical access to the processes triggered by photodynamic therapy (PDT). Partial irradiation of a photosensitized melanoma triggered cell death in non-irradiated tumor cells. Multiphoton intravital microscopy with genetically encoded fluorescence indicators revealed that bystander cell death was mediated by paracrine signaling due to adenosine triphosphate (ATP) release from connexin (Cx) hemichannels (HCs). Intercellular calcium (Ca2+) waves propagated from irradiated to bystander cells promoting intracellular Ca2+ transfer from the endoplasmic reticulum (ER) to mitochondria and rapid activation of …


Four Channel 6.5 Kv, 65 A, 100 Ns-100 Μs Generator With Advanced Control Of Pulse And Burst Protocols For Biomedical And Biotechnological Applications, Aleh Kandratsyeu, Uladzimir Sabaleuski, Luis Redondo, Andrei G. Pakhomov Jan 2021

Four Channel 6.5 Kv, 65 A, 100 Ns-100 Μs Generator With Advanced Control Of Pulse And Burst Protocols For Biomedical And Biotechnological Applications, Aleh Kandratsyeu, Uladzimir Sabaleuski, Luis Redondo, Andrei G. Pakhomov

Bioelectrics Publications

Pulsed electric fields in the sub-microsecond range are being increasingly used in biomedical and biotechnology applications, where the demand for high-voltage and high-frequency pulse generators with enhanced performance and pulse flexibility is pushing the limits of pulse power solid state technology. In the scope of this article, a new pulsed generator, which includes four independent MOSFET based Marx modulators, operating individually or combined, controlled from a computer user interface, is described. The generator is capable of applying different pulse shapes, from unipolar to bipolar pulses into biological loads, in symmetric and asymmetric modes, with voltages up to 6.5 kV and …


The Role Of Reactive Oxygen Species In The Immunity Induced By Nano-Pulse Stimulation, Siqi Guo, Niculina I. Burcus, Megan Scott, Yu Jing, Iurii Semenov Jan 2021

The Role Of Reactive Oxygen Species In The Immunity Induced By Nano-Pulse Stimulation, Siqi Guo, Niculina I. Burcus, Megan Scott, Yu Jing, Iurii Semenov

Bioelectrics Publications

Reactive oxygen species (ROS) are byproducts of tumor cells treated with Nano-Pulse Stimulation (NPS). Recently, ROS have been suggested as a contributing factor in immunogenic cell death and T cell-mediated immunity. This research further investigated the role of NPS induced ROS in antitumor immunity. ROS production in 4T1-luc breast cancer cells was characterized using three detection reagents, namely, Amplex Red, MitoSox Red, and Dihydroethidium. The efficiency of ROS quenching was evaluated in the presence or absence of ROS scavengers and/or antioxidants. The immunogenicity of NPS treated tumor cells was assessed by ex vivo dendritic cell activation, in vivo vaccination assay …


Oxygen Harvesting From Carbon Dioxide: Simultaneous Epoxidation And Co Formation, Han Xu, Muhammad Shaban, Sui Wang, Anas Alkayal, Dingxin Liu, Michael G. Kong, Felix Plasser, Benjamin R. Buckley, Felipe Iza Jan 2021

Oxygen Harvesting From Carbon Dioxide: Simultaneous Epoxidation And Co Formation, Han Xu, Muhammad Shaban, Sui Wang, Anas Alkayal, Dingxin Liu, Michael G. Kong, Felix Plasser, Benjamin R. Buckley, Felipe Iza

Bioelectrics Publications

Due to increasing concentrations in the atmosphere, carbon dioxide has, in recent times, been targeted for utilisation (Carbon Capture Utilisation and Storage, CCUS). In particular, the production of CO from CO2 has been an area of intense interest, particularly since the CO can be utilized in Fischer–Tropsch synthesis. Herein we report that CO2 can also be used as a source of atomic oxygen that is efficiently harvested and used as a waste-free terminal oxidant for the oxidation of alkenes to epoxides. Simultaneously, the process yields CO. Utilization of the atomic oxygen does not only generate a valuable product, …


Effect Of He Plasma Jet Versus Surface Plasma On The Metabolites Of Acute Myeloid Leukemia Cells, Dehui Xu, Ning Ning, Yujing Xu, Wenjie Xia, Hai-Lan Chen, Michael G. Kong Jan 2021

Effect Of He Plasma Jet Versus Surface Plasma On The Metabolites Of Acute Myeloid Leukemia Cells, Dehui Xu, Ning Ning, Yujing Xu, Wenjie Xia, Hai-Lan Chen, Michael G. Kong

Bioelectrics Publications

Cold atmospheric plasma, including plasma jet and surface plasma, can promote the apoptosis of cancer cells without causing significant damage to surrounding normal cells, which was hopeful to be applied to the clinical cancer therapy. However, experimental plasma devices used directly to clinical experiments has challenges in technology and methods, especially the difference in killing tumor cells efficiency of these two common plasma sources. Therefore, it is great necessity to explore the differences in treating tumors between different plasma sources. This paper achieved good killing efficiency by using two kinds of cold atmospheric plasma generating devices, namely plasma jet and …


Discharge Mode Transition In He/Ar Atmospheric Pressure Plasma Jet And Its Inactivation Effect Against Tumor Cells In Vitro, Bolun Pang, Zhijie Liu, Sitao Wang, Yuting Gao, Huaiyan Zhang, Feng Zhang, Xiamin Tantai, Dehui Xu, Dingxin Liu, Michael G. Kong Jan 2021

Discharge Mode Transition In He/Ar Atmospheric Pressure Plasma Jet And Its Inactivation Effect Against Tumor Cells In Vitro, Bolun Pang, Zhijie Liu, Sitao Wang, Yuting Gao, Huaiyan Zhang, Feng Zhang, Xiamin Tantai, Dehui Xu, Dingxin Liu, Michael G. Kong

Bioelectrics Publications

Discharge characteristic comparisons between He and Ar plasma jets have been extensively reported, but is rarely reported for the comprehensive study of discharge mode transition from He jet to Ar jet, especially its induced liquid chemistry and biological effect. In this paper, we investigate the plasma jet mode transformation by varying the Ar contents in the He/Ar mixing working gas, particularly focusing on the effect of liquid chemistry of plasma activated water (PAW) and the corresponding inactivation effect against tumor cells in vitro. The mode transition process from He jet to Ar jet is characterized by the discharge images, …


Test-Retest Reliability And Minimal Detectable Change Of The Computerized Dynamic Posturography Proprio For Adults With Chronic Traumatic Brain Injury, Guilherme Manna Cesar, Thad W. Buster, Judith M. Burnfield Jan 2021

Test-Retest Reliability And Minimal Detectable Change Of The Computerized Dynamic Posturography Proprio For Adults With Chronic Traumatic Brain Injury, Guilherme Manna Cesar, Thad W. Buster, Judith M. Burnfield

Department of Mechanical and Materials Engineering: Faculty Publications

Purpose: Balance deficits after brain injury, including reactive recovery from unexpected perturbations, can persist well after rehabilitation is concluded. While traditional clinical assessments are practical, the anticipatory nature of the tasks may mask perceptible balance control. Computerized dynamic posturography can directly quantify capacity to respond to unexpected, external perturbations. This study examined the reliability of the computerized dynamic posturography assessment with the device PROPRIO® 4000 in adults with traumatic brain injury and created the minimal detectable change for its standardized test.

Methods: Ten adults (ages 21–55 years) with chronic (average 10 ± 6 years post-injury) severe (loss of consciousness 2–75 …


Perceived Importance Of Aac Messages To Support Communication In Rehabilitation Settings, Susan Koch Fager, Judith M. Burnfield, Chase M Pfeifer, Tabatha Sorenson Jan 2021

Perceived Importance Of Aac Messages To Support Communication In Rehabilitation Settings, Susan Koch Fager, Judith M. Burnfield, Chase M Pfeifer, Tabatha Sorenson

Department of Mechanical and Materials Engineering: Faculty Publications

Purpose: Permanent or temporary speech loss can occur due to a variety of medical conditions and often requires individuals to use augmentative and alternative communication (AAC) strategies and technologies to support communication. The use of AAC in medical and rehabilitation settings is critical to ensure the health, safety and psychological well-being of communicatively vulnerable individuals.

Method: This study surveyed the perceived importance of communication messages within five categories (Basic Needs, Patient-Provider Specific Communication, Social, Feelings, and Messages for Young Children) by individuals with disability who have undergone recent medical care as well as by rehabilitation care providers.

Results: Results indicated …


Feasibility Of Motor-Assisted Elliptical To Improve Walking, Fitness And Balance Following Pediatric Acquired Brain Injury: A Case Series, Judith M. Burnfield, Guilherme Manna Cesar, Thad W. Buster Jan 2021

Feasibility Of Motor-Assisted Elliptical To Improve Walking, Fitness And Balance Following Pediatric Acquired Brain Injury: A Case Series, Judith M. Burnfield, Guilherme Manna Cesar, Thad W. Buster

Department of Mechanical and Materials Engineering: Faculty Publications

Purpose: Walking, fitness, and balance deficits are common following acquired brain injury (ABI). This study assessed feasibility, acceptability, and usefulness of a modified motor-assisted elliptical (ICARE) in addressing walking, fitness, and balance deficits in children with chronic ABIs.

Methods: Three children (> 5 years post-ABI) completed 24 ICARE exercise sessions (exercise time, speed, and time overriding motor-assistance gradually increased) to promote mass repetition of gait-like movements and challenge cardiorespiratory fitness. Parents’ and children’s perceptions of ICARE’s safety, comfort, workout, and usability were assessed. Cardiovascular response, gait and balance outcomes were assessed.

Results: No adverse events occurred. Parent’s …