Biomedical Engineering and Bioengineering Commons^™

The Paradox Of Pulmonary Vascular Resistance: Restoration Of Pulmonary Capillary Recruitment As A Sine Qua Non For True Therapeutic Success In Pulmonary Arterial Hypertension, David Langleben, Stylianos E. Orfanos, Benjamin D. Fox, Nathan Messas, Michele Giovinazzo, John D. Catravas

Bioelectrics Publications

Exercise-induced increases in pulmonary blood flow normally increase pulmonary arterial pressure only minimally, largely due to a reserve of pulmonary capillaries that are available for recruitment to carry the flow. In pulmonary arterial hypertension, due to precapillary arteriolar obstruction, such recruitment is greatly reduced. In exercising pulmonary arterial hypertension patients, pulmonary arterial pressure remains high and may even increase further. Current pulmonary arterial hypertension therapies, acting principally as vasodilators, decrease calculated pulmonary vascular resistance by increasing pulmonary blood flow but have a minimal effect in lowering pulmonary arterial pressure and do not restore significant capillary recruitment. Novel pulmonary arterial hypertension …

In Vitro And In Vivo Correlation Of Skin And Cellular Responses To Nucleic Acid Delivery, M. Bosnjak, K. Znidar, A. Sales Conniff, T. Jesenko, B. Markelc, Nina Semenova, J. Tur, K. Kohena, S. Kranjc Brezar, L. Heller, M. Cemazar

Bioelectrics Publications

Skin, the largest organ in the body, provides a passive physical barrier against infection and contains elements of the innate and adaptive immune systems. Skin consists of various cells, including keratinocytes, fibroblasts, endothelial cells and immune cells. This diversity of cell types could be important to gene therapies because DNA transfection could elicit different responses in different cell types. Previously, we observed the upregulation and activation of cytosolic DNA sensing pathways in several non-tumor and tumor cell types as well in tumors after the electroporation (electrotransfer) of plasmid DNA (pDNA). Based on this research and the innate immunogenicity of …

Challenges Of Constructing Entrainment Map For Arbitrary Circadian Models, Yuxuan (Nelson) Wu

Honors Theses

The entrainment map, developed by Dr.Diekman and Dr.Bose, is claimed to be a 1-dimensional map that produces a better prediction for phase-locking than methods than the phase response curve for circadian models. In his paper, he constructs the entrainment map for the two-dimensional circadian model, the Novak-Tyson model, and the other two higher-dimensional circadian models. For this thesis, we concentrate on exploring if it is viable to construct the entrainment map for other circadian models that are not included in his paper: the Becker-Weimann model and the Relogio model. In addition, we discuss the challenges of constructing the entrainment map …

The Aquatic Particle Number Quandry, Alexander B. Bochdansky, Huanqing Huang, Maureen H. Conte

OES Faculty Publications

Optical surveys of aquatic particles and their particle size spectra have become important tools in studies of light propagation in water, classification of water masses, and the dynamics of trophic interactions affecting particle aggregation and flux. Here, we demonstrate that typical settings used in image analysis vastly underestimate particle numbers due to the particle – gel continuum. Applying a wide range of threshold values to change the sensitivity of our detection system, we show that macrogels cannot be separated from more dense particles, and that a true particle number per volume cannot be ascertained; only relative numbers in relation to …

การสร้างภาพสามมิติของกระดูกต้นขาที่แตกหักจากภาพถ่ายรังสีสองมุมมองด้วยวิธีการเรียนรู้เชิงลึก, ดนุพงษ์ บุตรทองคำ

Chulalongkorn University Theses and Dissertations (Chula ETD)

ภาวะกระดูกต้นขาส่วนปลายหักนั้นเป็นภาวะบาดเจ็บที่ค่อนข้างรุนแรง มีสาเหตุจากการบาดเจ็บทั้งภาวะบาดเจ็บจากอุบัติเหตุและการหักผ่านรอยโรค การวินิจฉัยและการวางแผนการผ่าตัดเป็นขบวนการที่สำคัญในการรักษา ซึ่งต้องพึ่งพาการถ่ายภาพรังสีเอกซเรย์และเอกซเรย์คอมพิวเตอร์ อย่างไรก็ตามการถ่ายภาพรังสีเอกซเรย์คอมพิวเตอร์นั้นมีค่าใช้จ่ายมาก ปริมาณรังสีสูง และใช้ระยะเวลาในการถ่ายภาพยาวนานกว่าการถ่ายภาพเอกซเรย์ ดังนั้นการสร้างภาพสามมิติของกระดูกต้นขาที่แตกหักจากถ่ายภาพรังสีเอกซเรย์จึงเป็นที่ต้องการและเป็นโจทย์ปัญหาที่ยังไม่ได้รับการแก้ไข อีกทั้งยังขาดแคลนข้อมูลในการวิจัย งานวิจัยนี้จึงนำเสนอโมเดลสร้างภาพสามมิติของกระดูกต้นขาส่วนปลายที่แตกหักจากภาพถ่ายรังสีสองมุมมอง เพื่อเพิ่มมโนภาพการมองเห็นแบบสามมิติใช้สำหรับการวินิจฉัยและการวางแผนการผ่าตัด โมเดลการสร้างภาพสามมิติได้ประยุกต์ใช้การเรียนรู้เชิงลึกซึ่งเป็นโครงข่ายประสาทเทียมคอนโวลูชันแบบพีระมิด คลาสช่วยฝึกสอนเป็นตัวแทนของบริเวณกระดูกที่แตกหักช่วยสนับสนุนการเรียนรู้รายละเอียดการรอยแตกหักของโมเดล เนื่องจากตัวอย่างภาพสำหรับฝึกสอนมีไม่เพียงพอ เทคนิคตัวอย่างฝึกสอนที่แตกหักจึงถูกพัฒนาขึ้นเพื่อขยายขนาดตัวอย่างสำหรับฝึกสอนและเพื่อเพิ่มความแม่นยำของผลลัพธ์ นอกจากนี้โมดูลสำหรับผสมคุณสมบัติตามแนวแกนจึงถูกพัฒนาขึ้นภายในโมเดลเพื่อเอาชนะปัญหาความคลาดเคลื่อนเชิงมุมระหว่างภาพถ่ายรังสี โมเดลที่นำเสนอสามารถทำงานกับชุดข้อมูลที่มีคลาดเคลื่อนเชิงมุมระหว่างภาพถ่ายรังสีได้ถึง 10 องศา โดยมีค่า mIoU ที่ 0.827±0.083SD. และ mASSD มีค่า 1.043±0.481SD. โมเดลที่นำเสนอให้รูปทรงกระดูกต้นขาและรายละเอียดของรอยแตกหักที่แม่นยำใกล้เคียงกับความเป็นจริง

Innovative Techniques Of Neuromodulation And Neuromodeling Based On Focal Non-Invasive Transcranial Magnetic Stimulation For Neurological Disorders, Ivan C. Carmona-Tortolero

Theses and Dissertations

This dissertation aims to develop alternative technology that improves the current range of application of transcranial magnetic stimulation (TMS), on a scale that would permit defining specific non-invasive treatments for Parkinson’s disease and other neurological disorders. This is accomplished through three specific objectives. 1) The design of a neurostimulation system that increases the focality in TMS to regions of narrow target areas and variable depths in the brain cortex. 2) The assessment of the feasibility of novel high-frequency neuromodulation techniques that would allow increasing the focality in deeper areas beyond the cortical surface. 3) The development of a computational model …

Improving The Early Detection Of Cardiovascular Toxicity Secondary To Radiotherapy For Lung Cancer Via Patient-Specific Quantitative Magnetic Resonance Imaging, Alireza Omidi

Theses and Dissertations

Purpose: To assess the cardiopulmonary-induced dose variation on the left ventricle (LV) and evaluate the spatiotemporal evolution of cardiac/aortic function following radiotherapy (RT).

Methods: 8 lung cancer patients who were scheduled to receive RT were recruited for this study. Each patient underwent one 4D-CT at baseline. MRI scans including cine GRE, T1/T2, LGE, and 4D-flow were acquired at baseline, 3-months and 6-months post-RT to evaluate the cardiac/aortic function. Finally, image registration was used to assess the cardiopulmonary-induced dose variation on the LV.

Results: Mean RT-dose was minimum during inspiration and systole (at expiration). No significant differences were found in the …

Universal Design In Bci: Deep Learning Approaches For Adaptive Speech Brain-Computer Interfaces, Srdjan Lesaja

Theses and Dissertations

In the last two decades, there have been many breakthrough advancements in non-invasive and invasive brain-computer interface (BCI) systems. However, the majority of BCI model designs still follow a paradigm whereby neural signals are preprocessed and task-related features extracted using static, and generally customized, data-independent designs. Such BCI designs commonly optimize narrow task performance over generalizability, adaptability, and robustness, which is not well suited to meeting individual user needs. If one day BCIs are to be capable of decoding our higher-order cognitive commands and conceptual maps, their designs will need to be adaptive architectures that will evolve and grow in …

Biomarkers Of Inflammation And Oxidative Stress In The Prediction And Management Of Acute Coronary Syndrome, Udaya Ralapanawa, Sivakanesan R

Health Sciences

The assessment of patients presenting with chest pain or symptoms indicative of cardiac ischemia remains a diagnostic challenge. Many types of research have focused on the search for ideal biological markers for the rapid detection of cardiac cell injuries. Markers of inflammation and oxidative stress are the way forward. At present, the biomarker most widely used for diagnosing acute coronary syndrome is cardiac troponin though it has some limitations. Apart from cardiac troponin, several other biomarkers, especially inflammation and oxidative stress markers in acute coronary syndrome, have been investigated. However, most of them still require validation in further studies. As …

Electroporation And Cell Killing By Milli- To Nanosecond Pulses And Avoiding Neuromuscular Stimulation In Cancer Ablation, Emily Gudvangen, Vitalii Kim, Vitalij Novickij, Federico Battista, Andrei G. Pakhomov

Bioelectrics Publications

Ablation therapies aim at eradication of tumors with minimal impact on surrounding healthy tissues. Conventional pulsed electric field (PEF) treatments cause pain and muscle contractions far beyond the ablation area. The ongoing quest is to identify PEF parameters efficient at ablation but not at stimulation. We measured electroporation and cell killing thresholds for 150 ns–1 ms PEF, uni- and bipolar, delivered in 10- to 300-pulse trains at up to 1 MHz rates. Monolayers of murine colon carcinoma cells exposed to PEF were stained with YO-PRO-1 dye to detect electroporation. In 2–4 h, dead cells were labeled with propidium. Electroporation and …

Photoacoustic Imaging For Image-Guided Interventions, Samuel John

Wayne State University Dissertations

Image-guided surgeries and therapeutic procedures utilize imaging modalities to enhance the surgeon’s capability of visualizing and guiding the medical instruments within the body. One such application is the endovenous laser ablation (EVLA), which utilizes an ultrasound (US)-guided catheter carrying high power continuous wave (CW) energy for treating varicose veins. Varicose veins, a condition defined by venous insufficiency, affects nearly 40 million people in the United States annually. In EVLA procedures, US limitations including angular dependency, poor contrast-to-noise ratio, poor signal-to-noise ratio, and artifacts limit the ability of the surgeon to detect the catheter tip within the vein. Furthermore, the absence …

Reporter Chondrocyte Optimization Of Bioinks For Zonal 3d Bioprinting Of Cartilage, Kari Martyniak

Electronic Theses and Dissertations, 2020-2023

Osteoarthritis (OA) is the most common form of arthritis, often thought of as a disease of the elderly, but post traumatic OA predominantly impacts younger individuals. Articular cartilage is the tissue that coats the end of your bones in synovial joints. Since cartilage has limited healing capacity, defects, or injuries to it progressively erodes down to the subchondral bone. Unfortunately, current treatment options all have limitations, particularly for younger patients. Cartilage has a specific zonal architecture that is distinguished by the different cell morphologies and arrangements, biochemical composition, and mechanical properties. 3D bioprinting is a tissue engineering technique that involves …

An Electrochemical, Fluidic, Chip-Based Biosensor For Biomarker Detection, Lauren Bell

Theses and Dissertations--Biomedical Engineering

Biosensors and their use in both the research and clinical field for the detection and monitoring of critical biomarkers are prevalent and constantly improving. However, continued research needs to be done to address shortcomings, such as low sensitivity, poor specificity, and poor readiness for integration into research use and patient care. The objective of this research was to create a combined fluidic, chip-based biosensor that could detect different biomarkers with high sensitivity and ease of use. For assessing the developed sensor, three separate biomarkers were tested: glucose, cholesterol, and oxygen. Both the glucose biosensor and cholesterol biosensor were combined with …

Characterizing The Internal Porous Structure Of Equine Proximal Sesamoid Bones Subjected To Race Training Using Fast Fourier Transforms, Joseph Erik Davis

Theses and Dissertations--Biomedical Engineering

The equine racing industry is one of the main proponents in Kentucky’s economic infrastructure. In this industry there has come a need to investigate the nature of the proximal sesamoid bone (PSB). Breakdowns involving the PSBs are the leading cause in racehorse deaths in the industry, with still little known about what causes this bone to fracture. This study seeks to shed insight by investigating the internal structure of the PSB. Using microCT scanning, the internal porous structure was captured. From there, noticeable differences in the pores were noticed and quantified using fast Fourier transform (FFT) analysis.

The dominant peak …

Use Of Image Processing Techniques And Machine Learning For Better Understanding Of T Gondii Biology, Amer Asiri

Theses and Dissertations--Biomedical Engineering

Almost one in every three people worldwide is infected with Toxoplasma gondii (T. gondii). The biology and growth of the parasite’s bradyzoite form in host tissue cysts are not well understood. T. gondii’s metabolic state influences the morphology of its single mitochondrion, which can be visualized using fluorescence microscopy with specific dyes. Hence, fluorescence microscopy images of cysts purified from infected mouse brains carry biological information about bradyzoites, the poorly understood form of the parasite within them. With the help of fluorescence microscopy techniques, previous studies extracted images of the mitochondrion, nucleus, and the inner membrane complex (IMC) …

Numerical And Scaling Study On Application Of Inkjet Technology To Automotive Coating, Masoud Arabghahestani Dr.

Theses and Dissertations--Mechanical and Aerospace Engineering

A thorough literature review identified lack of precision control over quality of droplets generated by the currently available industrial sprayers and a growing need for higher quality droplets in the coating industry. Particularly, lack of knowledge and understanding in continuous inkjets (CIJ) and drop-on-demand (DOD) technologies is identified as significant. Motivated by these needs, this dissertation is dedicated to computational fluid dynamics (CFD) and scaling studies to improve existing inkjet technologies and develop new designs of efficient coating with single and/or multiple piezoelectric sensors to produce on-demand droplets. This dissertation study aims at developing a new DOD type coating technology, …

Optimization Of Electrically Driven Fluid Flow Through Tissue Hydrogels, Joseph C. Walker

Electronic Theses and Dissertations

No abstract provided.

Framework For The Evaluation Of Perturbations In The Systems Biology Landscape And Inter-Sample Similarity From Transcriptomic Datasets — A Digital Twin Perspective, Mariah Marie Hoffman

Dissertations and Theses

One approach to interrogating the complexities of human systems in their well-regulated and dysregulated states is through the use of digital twins. Digital twins are virtual representations of physical systems that are descriptive of an individual's state of health, an object fundamentally related to precision medicine. A key element for building a functional digital twin type for a disease or predicting the therapeutic efficacy of a potential treatment is harmonized, machine-parsable domain knowledge. Hypothesis-driven investigations are the gold standard for representing subsystems, but their results encompass a limited knowledge of the full biosystem. Multi-omics data is one rich source of …

Revision Total Hip Femoral Stem Micromotion And Statistical Shape Modeling Of The Knee, William Fugit

Electronic Theses and Dissertations

The first purpose of this thesis was to compare the amount of micromotion seen in the femoral stem in a revision total hip arthroplasty between simple loading conditions and loading conditions derived from activities of daily living, through the use of experimental and computational methods. The amount of micromotion at the bone-implant interface was larger for activities of daily living, with ranges of 200μm more than the largest simple loading conditions. The second purpose of this thesis was to compare measurements of accuracy in a statistical shape model between individual bone and joint-level models, specifically for the knee. Using computational …

The Lognometer: A New Normalized And Computerized Device For Assessing The Neurodevelopment Of Fine Motor Control In Children, Christian O'Reilly, Rejean Plamondon, Nadir Faci

Publications

Motor skills are fundamental for the development of children. Neurodevelopmental tests currently used by professionals for measuring motor control maturity exhibit several limitations. To address some of these, we have designed the Lognometer, a tablet-based device that can run computerized neuromotor tests. To normalize this tool against a representative population, we collected handwritten triangles from 780 children. We used the Sigma-Lognormal model and a prototype-based parameter estimation algorithm to analyze these movements. To ensure clinical acceptance, we developed an explainable solution relying on statistical regression. We evaluated how well the proposed lognormal decomposition captures the motor control maturation between 6 …