Open Access. Powered by Scholars. Published by Universities.®

Biomedical Engineering and Bioengineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Rowan University

Theses/Dissertations

2023

Articles 1 - 6 of 6

Full-Text Articles in Biomedical Engineering and Bioengineering

Evolutionary Conservation And Times Of Action Of Heterochronic Genes, Maria Ivanova Nov 2023

Evolutionary Conservation And Times Of Action Of Heterochronic Genes, Maria Ivanova

Theses and Dissertations

The heterochronic pathway of C. elegans is the most well-characterized system to date for controlling the sequence and timing of developmental events. However, we still have critical unanswered questions to address. First, little is known about the evolution of the heterochronic pathway, and of developmental timing in general. To determine if the roles of major heterochronic genes are conserved, I made mutants in orthologs of these genes in C. briggsae, using CRISPR/Cas9. My studies revealed a significant drift in the roles of some of the genes, although all of them are still involved in the developmental timing regulation, and several …

Go to article

Advanced Processing Techniques For Electrospun Nanofibers: Investigating Annealing And Laser Zone-Drawing Effects On Material Characteristics, Matthew D. Flamini Sep 2023

Advanced Processing Techniques For Electrospun Nanofibers: Investigating Annealing And Laser Zone-Drawing Effects On Material Characteristics, Matthew D. Flamini

Theses and Dissertations

Electrospun nanofibers hold potential for a wide range of commercial and scientific applications; however, their properties must be optimized through post-processing treatments to achieve optimal performance. This dissertation investigates the effects of annealing and laser zone-drawing on electrospun nanofiber properties. Annealing polycaprolactone nanofibers at 70°C results in the highest rate of crystallization and molecular alignment, impacting long-term stability and mechanical properties. A multivariate linear model incorporating crystallinity and molecular alignment predicts the material properties resulting from annealing under different conditions. Laser zone-drawing experiments reveal that polylactide fiber thinning under laser irradiation primarily occurs due to drawing rather than ablation. Steady-state …

Go to article

Chemical And Polymer Characterization Of The Potential Modes Of Degradation Of An Injectable Nucleus Pulposus Replacement Device, Antonio G. Abbondandolo Jun 2023

Chemical And Polymer Characterization Of The Potential Modes Of Degradation Of An Injectable Nucleus Pulposus Replacement Device, Antonio G. Abbondandolo

Theses and Dissertations

HYDRAFIL™ is a poly(vinyl alcohol)/poly(ethylene glycol)-based hydrogel nucleus pulposus replacement device that is injected in situ and has demonstrated efficacy in lowering the prevalence and pain associated with back. In this work, we developed a method to analyze HYDRAFIL™ polymer composition using (TGA) and characterized intermolecular bonding interactions within the hydrogel through (FTIR). To function as a permanent implant for nucleus pulposus replacement, HYDRAFIL™ must be stable when exposed to a multitude of degradation pathways, namely, thermal, chemical, and mechanical. We subjected HYDRAFIL™ to accelerated thermal and chemical degradation pathways and described compositional, physical and chemical property changes using a …

Go to article

Efficient Scopeformer: Towards Scalable And Rich Feature Extraction For Intracranial Hemorrhage Detection Using Hybrid Convolution And Vision Transformer Networks, Yassine Barhoumi Mar 2023

Efficient Scopeformer: Towards Scalable And Rich Feature Extraction For Intracranial Hemorrhage Detection Using Hybrid Convolution And Vision Transformer Networks, Yassine Barhoumi

Theses and Dissertations

The field of medical imaging has seen significant advancements through the use of artificial intelligence (AI) techniques. The success of deep learning models in this area has led to the need for further research. This study aims to explore the use of various deep learning algorithms and emerging modeling techniques to improve training paradigms in medical imaging. Convolutional neural networks (CNNs) are the go-to architecture for computer vision problems, but they have limitations in mapping long-term dependencies within images. To address these limitations, the study explores the use of techniques such as global average pooling and self-attention mechanisms. Additionally, the …

Go to article

Polyethyleneimine Shell Nucleic Acid Nanostructures From Gold Nanoparticle Template For Chemotherapeutic Drug Delivery, Brendan Guy Rucci Jan 2023

Polyethyleneimine Shell Nucleic Acid Nanostructures From Gold Nanoparticle Template For Chemotherapeutic Drug Delivery, Brendan Guy Rucci

Theses and Dissertations

The next generation of anticancer agents will emerge from rationally designed nanostructured materials. This work involved the synthesis and characterization of novel hollow DNA-conjugated gold nanoparticles (DNA-AuNPs) for controlled drug delivery. Polyethyleneimine (PEI) was bound to citrate-capped AuNPs, forming polymer-shell nanoparticles. Dissolution of the gold core via iodine formed hollow core polymeric nanoparticles (HCPPs) and a high density of DNA (85 molecules/particle) containing daunorubicin was conjugated. Particles were spherical with an average diameter of 105.7±17.3 nm and zeta potential of 20.4±3.54 mV. We hypothesize the DNA backbone electrostatically condensed to the primary amines on the surface of the particle toroidally, …

Go to article

A 3d Bioprinted Hydrogel Microfluidic Device For Screening Applications, Anant Bhusal Jan 2023

A 3d Bioprinted Hydrogel Microfluidic Device For Screening Applications, Anant Bhusal

Theses and Dissertations

The microfluidic enabled the integration of engineered miniaturized tissue models for drug screening. Conventional polydimethylsiloxane or plastic-based devices require multiple fabrication steps, which are challenging. We developed a 3D bioprinting approach to create prototypes of hydrogel-based multi-material microfluidic devices integrated with microtissue models. The approach utilizes poly(ethylene glycol) diacrylate and gelatin-methacryloyl to create microfluidic chips using multi-material bioprinting capacity with a high resolution of 15µm on x-y and 50µm on the z-axis and post-printing viability of >90%. We demonstrated easy regulation of stiffness from 24±5 kPa to 1,180±9 kPa and burst pressure from 16±1kPa to 256±19 kPa in the chip …

Go to article