Engineering Commons^™

Development Of A 3d Printed Conductive Biopolymer For Cardiac Tissue Engineering, Britanny Lizeth Stark

Open Access Theses & Dissertations

Cardiovascular disease (CVD) is the leading cause of death in the US, with approximately 859,000 deaths each year. The major contributor to CVD is Acute Myocardial Infarction (AMI), which causes the death of approximately 25% of the cardiomyocytes present in the left ventricle of the heart. After AMI, the adult human heart has a very limited regenerative capacity. Moreover, the electrical propagation of the myocardium is severely disrupted, making the heart more susceptible to failure and patient death. However, current pharmacological treatments do not address the loss of cardiomyocytes and the disruption of electrical propagation in the heart. Tissue engineering …

Integration Of Biomedical Engineering And Computer Vision For Morphological Alteration Identification In Diabetic Cardiomyopathy: An Analysis And Evaluation Stra Tegy, Monica Delgado

Open Access Theses & Dissertations

Diabetic cardiomyopathy (DCM) is a type of heart disease that affects people with diabetes. It is characterized by changes in the structure and function of the heart, including thickening and stiffening of the heart muscle, impaired relaxation of the heart, and reduced pumping function. DCM is considered an ailment of the heart muscle and an increased risk factor in people with type 2 diabetes mellitus (T2DM). Although the exact mechanisms behind DCM are not fully understood, high blood glucose levels are known to contribute to the development and progression of the disease.While many options to manage and diagnose DCM have …

Engineering 3d Bioprinted Cardiac Spheroidal Droplets With Cardiomyocytes And Cardiac Fibroblasts For Tissue Engineering And Drug Cytotoxicity Studies, Raven El Khoury

Open Access Theses & Dissertations

Engineering is the supreme human endeavor that involves harnessing the scientific understanding of the natural world to design and invent objects to improve the society around us. Biomedical engineering is the implementation of concepts acquired from engineering in biology and medicine that aims to improve human health through the integration of engineering with biomedical sciences. The mission of a biomedical engineer is to develop technologies that help advance the quality of peopleâ??s health using various tools and materials with one passion and goal: making the patient's life longer and easier. Tissue engineering is developed from the field of biomaterials and …

Fetal Electrocardiogram Detection And Analysis From Maternal Abdominal Ecg For Diagnosis Of Fetal Heart Rhythm Abnormalities, Claudia L. Angel

Open Access Theses & Dissertations

Fetal cardiac arrhythmias are present in about 1–3% of pregnancies and account for about 10–20% of the referrals to fetal cardiology around the world. Most fetal arrhythmias are benign; however, some can cause fetal hydrops, preterm delivery, and higher perinatal morbidity and mortality. The evolution and treatment of fetal arrhythmia depend on a timely and complete diagnosis. However, conventional methods used in clinical practice for fetal arrhythmia diagnosis are limited since they do not reflect the primary electrophysiological conduction processes in the myocardium. Fetal electrocardiography (fECG) has the potential to better support fetal arrhythmia diagnosis through the continuous analysis of …

Design Of A Hemi-Anechoic Chamber For Acoustic Testing Of Hearing Devices And Development Of Custom-Designed 3d Printed Pinnae For Accurate Representation Of The Anatomical Frequency Response, Hector Hugo Estrada Medinilla

Open Access Theses & Dissertations

Sound localization is the capacity to identify the general location from which a sound is originating. The primary anatomical feature responsible for the ability to localize sound is the external portion of the ear, also known as the auricle or pinna. This faculty is significantly hindered when the ear is obstructed, as is the case with hearing protection devices (HPD), which act as a barrier between sound waves and the ear canal. In the case of electronic HPDs, certain frequencies are entirely filtered out by a digital sound processor (DSP) while the remaining frequencies are delivered directly into the ear …

Development Of A Custom, 3d-Printed, Multi-Microphone, Noise-Cancelling, Hearing Protection Device With A Magnetically Attached Printed Ear Canal For Sound Localization Preservation, Brenda Leticia Valadez Mesta

Open Access Theses & Dissertations

Hearing loss is a prominent health issue that affects a significant fraction of the global population. One of the main causes behind hearing loss is exposure to harmful noise levels in the workplace. There have been multiple efforts to prevent hearing loss from excessive noise in occupational settings, such as hearing conservation programs and use of hearing protection devices (HPDs), however, these are often ineffective. Although HPDs are frequently available in the workspace, they are not used as intended since they usually generate discomfort and hindered sound localization. The loss of sound localization can be hazardous in occupational settings, since …

The Mobility And Cognitive Mechanisms Involved In Altering Gait Speed In Children With Autism Spectrum Disorder, Alyssa Olivas

Open Access Theses & Dissertations

Autism is a socio-behavioral disorder, and diagnoses are conducted through behavioral screening instruments. Recent research suggests motor deficits may be a core symptom of the disorder, as children with autism present with deficits in motor development, locomotor skills, and postural instability. In addition, children with autism often have affected, executive function, attention, and perception cognitive domains. Different gait speeds have been used to examine gait adaptations in other clinical populations. Additionally, individuals with decreased cognitive abilities have demonstrated difficulties in modulating their walking speed. There is limited research on mechanisms children with autism use to alter their gait speed, or …

Cell Bioprinting: A Novel Approach For Alpha Cell To Beta Cell Transdifferentiation, Atzimba Casas

Open Access Theses & Dissertations

Diabetes is a chronic disease that occurs in the body when the pancreas fails to either produce insulin (TID) or does not effectively use the insulin produced (TIID) and poses further health complications as well as an insurmountable economic impact.[1] Type I diabetes is an autoimmune disease characterized by a deficient amount of insulin production on account of the body’s immune system destroying its own β-cells.[2] Current diabetes treatment methods include the administration of insulin via injections or islet transplantation therapy. However, although both are viable options, they come with limitations that make the managing of this disease difficult. It …

Evaluation Of Varying Graphene Oxides Through Their Physicochemical Characterizations On Erythrocytes, Hs27 Cells, Escherichia Coli And Staphylococcus Aureus Bacteria Cell Lines, To Assess Graphene Oxides Cytotoxicity., Miriam Montana

Open Access Theses & Dissertations

Research on the toxicity of Graphene Oxides (GO) has captivated interest in the field of material science, environmental sciences, and medicine for their avail significance in biomedical engineer applications either as integrates, enhancements, or in the making of medical devices. Moreover, there is still a lack of understanding as to what characteristics on GOs causes them to be cytotoxic at a cellular level. In our study we synthesized four different GOs by varying in both the method used for oxidation (Modified Hummer’s method & Improved Marcano-Tour’s method), and the precursor parent graphite, for a standardization approach to aid in the …

Non-Invasive In-Vitro Glucose Monitoring Using Optical Sensor And Machine Learning Techniques For Diabetes Applications, Maryamsadat Shokrekhodaei

Open Access Theses & Dissertations

Diabetes is a major public health challenge affecting more than 451 million people. Physiological and experimental factors influence the accuracy of non-invasive glucose monitoring, and these need to be addressed before replacing the finger prick method with a non-invasive glucose measurement technique. Also, the suitable employment of machine learning techniques on experimental data can significantly improve the accuracy of glucose predictions.

This work includes the design, development, testing and data analysis of an optical based sensor for glucose measurements. The feasibility of non-invasive measurement of glucose within aqueous solutions that assimilate the composition of human blood plasma is investigated. The …

Engineering Cardiac Tissues With Three-Dimensional Bioprinting For Biomedical Applications, Matthew Alonzo

Open Access Theses & Dissertations

The role of a biomedical engineer is to solve unmet health-related needs that face society. For the past couple of decades, heart disease (HD) has remained the leading cause of mortality and morbidity worldwide. The disease is characterized by various pathologies that affect the heart. Indeed, malfunction of one of the bodyâ??s most vital organs is bound to manifest poor health and even death in patients. Despite advances in medicine and technology, heart disease continues to be prevalent and diminishes the quality of life for many around the world. Certainly, there exists a need for developing new tools to better …

Evaluation Of The Cytotoxyc Effects Of Lmdf5-7 On A Human T-Cell Leukemia Cell Line, Andrea F. Ibarra Chacon

Open Access Theses & Dissertations

According to World Health Organization (WHO), cancer is the second leading cause of death worldwide, with 9.6 million deaths in 2018 . In the United States, an estimated 434,982 people were living with cancer during 2017 . Leukemia is the most common blood cancer in children from birth to 14 years old . In particular, Hispanic children in the United States experience a higher incidence rate of leukemia . Therefore, the discovery of novel cancer therapies is necessary to help those affected survive the disease. A new compound, LMDF5-7 was investigated and found to have anticancer properties that can help …

3d Printing Of High Viscosity Fluids And Its Application In 3d Printing Of Prosthetic Teeth., Abhilash Aditya

Open Access Theses & Dissertations

The advancement in technology has brought forward non-conventional manufacturing methods that are efficient and advantageous for specific applications. 3D printing is one such outcome, whose applications stretch from biomedical applications to daily products. 3D printing is a rapidly growing technology, and innovative research developments have proven versatility in creating physical objects. Simplification and constant improvement in Fused Deposition Modeling (FDM) operation result from decades of research. However, 3D printing is material-specific and contributes to shortcomings in the technology. The build-material dictates the extrusion parameters, including the material discharge rate and head speed for a continuous flow. Customization being the prime …

Early Detection Of Asthma Via Enhanced Resolution Of Small Airways Using Ultra-Low Frequency Impulse Oscillometry, Christopher M. Aguilar

Open Access Theses & Dissertations

Examination of lung function for diagnosis and monitoring of diseases such as chronic obstructive pulmonary disease (COPD) and asthma can be performed with a variety of pulmonary function testing (PFT) techniques. The most commonly prescribed of these procedures are spirometry and whole-body plethysmography. However, these active participation tests depend on forced breathing maneuvers, may be physically exhausting, might not produce enough information, and are susceptible to being subject-dependent. In contrast, passive PFT approaches such as the forced oscillation technique (FOT) and the impulse oscillometry system (IOS) are increasingly being utilized for measuring lung mechanics because they require only minimal participation, …

Formulation Strategies To Enhance Solubility And Permeability Of Small Molecules For Drug Delivery Applications, Pradeep Kumar Bolla

Open Access Theses & Dissertations

All the new chemical entities/drug molecules intended for therapeutic use must be administered using an appropriate delivery system/dosage form to achieve maximum bioavailability. However, designing a drug delivery system is complex as several factors such as lipophilicity, molecular mass, crystallinity, ionic charge, polymorphic forms and hydrogen bonding) affect the solubility and permeability of these molecules. Biopharmaceutics drug classification system (BCS) categorizes the existing drugs into four classes based on the aqueous solubility and membrane permeability and it is reported that >70% of the drugs are poorly soluble and belong to BCS class II and BCS class IV. Several physical, chemical …

Supercritical Processed Decellularized Extracellualr Matrix As Regeneration Therapeutics Applying 3d Printing, Seungwon Chung

Open Access Theses & Dissertations

Extracellular matrix has been broadly applied and show great promise in medical applications and tissue engineering. Product of extracellular matrix (ECM) should be treated with decellularization and purification process. Supercritical carbon dioxide treatment is of particular interest for purifying ECM because of its medically available and rapid speed of process. However, it is not fully researched in treatment of biomaterials for tissue engineering. Therefore, we investigated optimal conditions of supercritical carbon dioxide processing in different extracting parameters from porcine adipose tissue. The 3-day, dual treatment including enzymatic decellularization and supercritical fluid extraction of pork adipose tissue were performed. Two types …

3d Printed Alginate-Based Zinc Oxide Nanoparticle Scaffolds For Wound Healing, Carol Cleetus

Open Access Theses & Dissertations

Effective treatment of chronic wounds is essential for the prevention of infection and scar tissue formation, requiring a novel approach to address the limitations of existing options. This study utilizes Calcium Chloride (CaCl2) crosslinked alginate, a common biomaterial widely used in wound dressing, and UV activated Zinc Oxide (ZnO) nanoparticles (NPs) for their potential hydroxyl radical mediated antibacterial applications. ZnO NPs were synthesized by combustion method from Zinc Nitrate Hexahydrate and Sucrose. Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) characterization were used to verify composition and NP size. Terephthalic Acid, used as a fluorescent probe, confirmed the generation of …

Regulation Of Schlafen 11 Expression, Christian Waldemar Corona Ayala

Open Access Theses & Dissertations

Schlafen 11 (SLFN11) is a member a family of proteins that can be found in mammals. Members of this family are involved in important functions. SLFN11 in particular has been identified as a restriction factor for several evolutionarily disparate viruses such as HIV-1 and Flaviviruses and to play an important role in DNA repair, sensitizing cells to chemotherapy. Despite its relevance SLFN11 remains largely uncharacterized. The aim of this research was to achieve a more comprehensive understanding the regulation mechanism of SLFN 11 expression. Before our research, it was only known that type I interferon (IFN) regulates SLFN11 levels. However, …

To Or Through The Skin: A Rational Design Of Transdermal Drug Delivery, Isaac Giovanni Deaguero

Open Access Theses & Dissertations

The skin is the largest organ in the body and plays many crucial roles through diverse functions ranging from protection, temperature regulation, energy storage via fat deposits, and is used to communicate with our surroundings. Various methods have been attempted to deliver drugs to target areas of the skin in effective dosages by a variety of means with limited success. Recently, advances in transdermal drug delivery have offered avenues previously unattainable through conventional means. Some of these new delivery methods have been reviewed, explored and offer promising results with the potential to carve a new avenue in the way therapeutic …

A Cellulose-Based Biological Sensor For The Quantitative Determination Of Glucose And Glycated Hemoglobin (Hba1c), Gilberto Henao-Pabon

Open Access Theses & Dissertations

ABSTRACT

Importance: Diabetes is a common world-wide disease characterized by insulin resistance and as result there is an increased risk of cardiovascular disease and other metabolic abnormalities, that contribute to irreversible end-organ damage. The cause of diabetes is multifactorial and includes genetic, inflammatory and environmental factors plus lifestyle issues. Because in diabetes there are high levels of glucose and glycated hemoglobin, these molecules are used in clinical settings for the acute and chronic management of diabetic patients.

Objectives: a. To design and build an electrochemical biological sensor using the enzyme Glucose Oxidase (GOX) to detect glucose in biological fluids.

b. …

The Study Of The Mouse Schlafen Family Members As Mediators Of Antiviral Activity, Julia Fernanda Hernandez

Open Access Theses & Dissertations

The Schlafen family of proteins was first characterized in 1988, and since then evidence of their relevance in different physiological and pathological situations have been accumulating although at a slow pace. Hence, the biological roles of these proteins remain ill-defined. The expression of these proteins is positively regulated by type 1 interferons, constituting a component of the innate immune response. Functions of these proteins vary from regulation of cell proliferation to restriction of viral infections. Recent studies have implicated SLFN11 and SLFN13 as inhibitors of HIV-1 infection2-4. The mechanism of action of SLFN11 resides in its capacity to regulate the …

Design And Characterization Of Thermal Inkjet Bioprinted Constructs For The Treatment Of Diabetic Foot Ulcers And Other Wound Healing Impaired Conditions, Luis Horacio Solis

Open Access Theses & Dissertations

Tissue engineering (TE) is a multidisciplinary practice focused on developing patient-specific constructs to repair, regenerate, or replace injured tissues and organs. One biofabrication process that has gained tremendous momentum in this field is bioprinting. Most, if not all bioprinting modalities embody the same principles of heat and shear due to mechanical forces or friction as cells are forced through narrow orifices. While it is important to examine the interaction between host and implanted constructs, it is also crucial to understand the direct effects that these bioprinting technologies have on cells before embedding them into TE applications.

The purpose of this …

The Study Of Non-Permanent Tattoo Ink Using Nano Silver Compounds And Untact 3d Printing Technology, Jisu Lee

Open Access Theses & Dissertations

Due to a recent epidemic of COVID 19, the possibility of 3D tattoo printing technology using the Internet of Things (IoT) control system developed in a non-face-to-face contact process was identified. A non-surgical tattoo process and hygiene safety differentiated with silver tattoo ink was used to solve the health problems arising from the surgical tattoo process and to identify 3D tattoo printing techniques through a non-personal contact concept. During the tattoo processing, the image selected by the customer is sent to a designated printer via an IoT control system in a separate location. A piston-type extruder (PTE) printing technique was …

Fabrication, Development, And Characterization Of Hipco Swcnt - Alginate Hydrogel Composites For Cellular Product Applications, Fabian Armando Alvarez-Primo

Open Access Theses & Dissertations

In this study, we designed, synthesized, and characterized ultrahigh purity single-walled carbon nanotube (SWCNT)-alginate hydrogel composites. Among the parameters of importance in the formation of an alginate-based hydrogel composite with single-walled carbon nanotubes, are their varying degrees of purity, their particulate agglomeration and their dose-dependent correlation to cell viability, all of which have an impact on the resultant compositeâ??s efficiency and effectiveness towards biomedical applications. To promote their homogenous dispersion by preventing agglomeration of the SWCNT, at first, we used three different surfactants-sodium dodecyl sulfate (SDS-anionic), cetyltrimethylammonium bromide (CTAB-cationic), and Pluronic F108 (nonionic). After experimentation and corroboration through evidence obtained …

Accurate Replication Of An Ear Pinnae Geometry For Use In Acoustic Testing Of Spatial Cues And Sound Localization, Alejandra Belmont

Open Access Theses & Dissertations

Additive manufacturing (AM) enables freedom of design as well as fabrication of complex objects such as the human hear. In medical modeling there is a need for patient-specific customizable parts. The outer human ear consists of these main parts: the pinna, which naturally filters sound, and the ear canal, which is the point at which sound enters before being moved up to the tympanic membrane, otherwise known as the eardrum. In an attempt to accurately replicate ear models, the use of scanning and reverse engineering methods was used. A comparison of 3D laser scanning systems was performed to determine their …

Impact Of Cryptococcus Neoformans Polysaccharide Capsule On Astrocytes, Yeon Hwa Woo

Open Access Theses & Dissertations

Cryptococcus neoformans is a neurotropic, opportunistic, encapsulated, yeast-like fungus that causes life-threatening meningoencephalitis in both healthy and immunocompromised individuals. C. neoformans infects 1,000,000 people and causes 210,000 deaths worldwide annually, mostly in sub-Saharan Africa. The polysaccharide capsule of C. neoformans is the fungus major virulent factor. Glucuronoxylomannan (GXM), the main component of the capsule is abundantly released into brain tissue during C. neoformans infection, causing immunosuppressive defects in the host. C. neoformans is inhaled from the environment, disseminate via bloodstream, and crosses the blood brain barrier (BBB) to cause cryptococcal meningoencephalitis (CM). Although CM causes significant mortality in HIV/AIDS patients, …

Segmentation And Registration Based Automatic Cancer Proton Treatment Analysis, Yang Zhang

Open Access Theses & Dissertations

Due to its low side effects, proton therapy is rapidly developing around the world. However, the time and labor it takes to deliver the treatment have prevented widespread use in the clinic setting. For this reason, an automatic proton treatment analysis system is needed to improve efficiency during the treatment process.

The challenge lies in improving the accuracy and speed of the current proton treatment analysis system. The Range shifter correction factor is considered the same value under any given condition in our treatment system. This approximate algorithm limits the accuracy of the proton treatment analysis system. In addition, medical …

Computer-Aided Classification Of Impulse Oscillometric Measures Of Respiratory Small Airways Function In Children, Nancy Selene Avila

Open Access Theses & Dissertations

Computer-aided classification of respiratory small airways dysfunction is not an easy task. There is a need to develop more robust classifiers, specifically for children as the classification studies performed to date have the following limitations: 1) they include features derived from tests that are not suitable for children and 2) they cannot distinguish between mild and severe small airway dysfunction.

This Dissertation describes the classification algorithms with high discriminative capacity to distinguish different levels of respiratory small airways function in children (Asthma, Small Airways Impairment, Possible Small Airways Impairment, and Normal lung function). This ability came from innovative feature selection, …

Varying Ratios Of Collagen I And Iii For The Study Of Fibrotic Conditions In Tissue Engineering, Brian Roman

Open Access Theses & Dissertations

Maintenance of collagen I (Col I) and III (Col III) in a 3:1 ratio is necessary to promote cardiac health. Increase in the relative amount of Col I within the myocardium, leads to an imbalance of Col I:III during cardiac fibrosis, which has damaging effects on cardiomyocytes (CM). To represent fibrous- and normal-cardiac tissue, gels composed of Col I:III ratios of 9:1 and 3:1 were developed and used to study resultant changes in CM function. Second harmonic generation (SHG) microscopy, used to image Col I fibers, displayed a decrease in image intensity with the addition of the non-second harmonic Col …

Bioprinted Mcf7 Breast Cancer Cells, An In Vitro Model For Drug Discovery, Aleli Campbell

Open Access Theses & Dissertations

Current breast cancer treatments are successful in eradicating this disease in the majority of patients, though there are quite a few cases where relapse or recurrence follow, which may lead to continued cancer therapy or death. Thermal inkjet bioprinting (BP) is a novel technique that is used to bioprint biomaterials or diverse cellular organisms to engineer tissue or organ models in vitro. In this Dissertation, we investigated the molecular effect of BP MCF7 breast cancer cells (BCC), cell survival of the cells when exposed to FDA approved systemic therapy alone and in combination with radiation and lastly, the ability of …