Biomedical Engineering and Bioengineering Commons^™

An Investigation Of Cross-Links On Crystallization And Degradation In A Novel, Photocross-Linkable Poly (Lactic Acid) System

USF Tampa Graduate Theses and Dissertations

Polymeric molecular structure consists of repeating units bonded together. Mechanicalproperties can be altered without affecting chemical makeup by altering the number of these units. Small molecules can be introduced and/or polymers can be modified to form bonds between molecular chains. Cross-linking, as this is called, also introduces mechanical variation with minimal effects on chemical composition. Lastly, polymer chains reorient themselves in response to intermolecular forces. This temperature dependent response is known as crystallization. Although chemistry is unaltered, mechanical properties can depend highly on the percent of the sample that is crystallized.

Cross-linking is known to enhance the mechanical properties of …

Strategic Research On Rebco High-Temperature Superconducting Tapes, Tianping Ying, Jinguang Cheng

Bulletin of Chinese Academy of Sciences (Chinese Version)

High-temperature superconducting materials, represented by REBCO (REBa2Cu3O7-δ, where RE denotes rare-earth elements), are of significant strategic importance in fields such as energy, healthcare, and large-scale scientific facilities due to their excellent performance in the liquid nitrogen temperature range. However, they still face severe challenges in long-tape uniformity, production cost, and engineering reliability. Future development must shift toward a “material-processing-application” collaborative innovation model, aiming at enhancing flux pinning, optimizing the interfaces and mechanical properties of the multilayer structure, and integrating scalable and intelligent fabrication technologies to promote the low-cost and stable production of high-performance tapes. This study analyzes the core application …

Fabrication Of Tissue Precursors Induced By Shape-Changing Hydrogels, Olukemi Akintewe

Graduate Theses and Dissertations

Scaffold based tissue reconstruction inherently limits regenerative capacity due to inflammatory response and limited cell migration. In contrast, scaffold-free methods promise formation of functional tissues with both reduced adverse host reactions and enhanced integration. Cell-sheet engineering is a well-known bottom-up tissue engineering approach that allows the release of intact cell sheet from a temperature responsive polymer such as poly-N-isopropylacrylamide (pNIPAAm). pNIPAAm is an ideal template for culturing cell sheets because it undergoes a sharp volume-phase transition owing to the hydrophilic and hydrophobic interaction around its lower critical solution temperature (LCST) of 32°C, a temperature close to physiological temperature. Compared to …

A Longitudinal Study Of Achilles Tendon Adaptation In Ncaa Division I Female Gymnasts: Associations With Menstrual Status, Birth Control Use, Pain, Limb Dominance, And Training Exposure, Mattie Hyde

Electronic Theses and Dissertations

This longitudinal study evaluated Achilles tendon (AT) thickness in 22 NCAA Division I (DI) female gymnasts across three consecutive seasons in relation to menstruation, birth control use, pain, limb dominance, training week, and year of collegiate competition. Weekly ultrasound and athlete survey data were analyzed using mixed-effects models for absolute AT thickness and change in thickness from baseline measurements. Associations were primarily characterized by interactions rather than uniform effects of individual predictors. A Pain × Limb Dominance × Week × Year interaction was associated with both thickness outcomes across season-specific and combined analyses, with relationship directions varying by limb, season …

An Hsus Report: Welfare Issues With Genetic Engineering And Cloning Of Farm Animals

HSUS Reports: Farm Industry Impacts on Animals

Developments in biotechnology have raised new concerns about animal welfare, as farm animals now have their genomes modified (genetically engineered) or copied (cloned) to propagate certain traits useful to agribusiness, such as meat yield or feed conversion. These animals suffer from unusually high rates of birth defects, disabilities, and premature death.

The Effects Of Solution Condition On Virus Filtration Performance, Fnu Namila

Theses and Dissertations

Virus filtration is an integral part of the downstream purification of mammalian cell culture-derived biotherapeutics to assure the viral safety of the products. Virus filtration membranes remove viruses based on a size-exclusion mechanism. Commercial parvovirus filers possess unique membrane structure and are designed to remove smaller non-enveloped parvoviruses with size 18-26 nm. However, some filters face issues, such as pre-mature fouling, the decline of filtrate flux, and reduction in virus retention. This doctoral dissertation focused on identifying the factors that influence the filtrate flux and the virus retention capability of commercial virus filters. The effects of solution pH and ionic …

Electromagnetic Theory And Applications, Nicholas Madamopoulos, George Kliros

Open Educational Resources

This book intends to provide both the fundamentals of Electromagnetics but also some practical applications of the concepts covered. Having taught electromagnetics for several years, the authors feel that many times the field of electromagnetics comes as “old” and often times students do not appreciate the concepts and their importance in everyday applications. The authors intend to accompany the EM concepts with life applications. Hence, students may see the direct impact of the knowledge they acquire through the study of the field of electromagnetics and better appreciate the field.

Poly(2-Hydroxyethyl Methacrylate) Hydrogels For Contact Lens Applications–A Review, Kushendarsyah Saptaji

Makara Journal of Science

The emerging technology in biomedical engineering requires biocompatible materials, which are also referred to as biomaterials. For a material to be considered biocompatible, it should not interact with human tissues in a harmful way, and vice versa. Various properties of biocompatible materials, such as mechanical and optical properties, have to be considered for different biomedical applications. One of the most popular applications of biomaterials is for contact lenses. Hydrogels, specifically poly(2-hydroxyethyl methacrylate) (PHEMA) hydrogels, are among the most popular ones in ophthalmologic applications, especially in soft contact lenses. This paper reviews the use of PHEMA hydrogels as one of the …

Densities Of Vegetable Oils And Fatty Acids, Hossein Noureddini

Papers in Biomaterials

Complete data for density as a function of temperature have been measured for a number of vegetable oils (cramhe, rapeseed, corn, soybean, milkweed, coconut, lesquerella), as well as eight fatty acids in the range CS to C,, at temperatures from above their melting points to llQ°C (23Q°F). The specific gravity and density measure mente were performed according to American Society for Testing and Materials (ASTM) standard test methods D 368, D 891 and D 1298 for hydrometers and a modified ASTM D 369 and D 891 for pycnometers. Correlation constants, based on the experimental data, are presented for calculating the …

Development Of Polymer Composite Based Enabling Technologies For Lab-On-A-Chip Devices, Vinicio Carias

Graduate Theses and Dissertations

This dissertation presents enabling technologies to fabricate thermo-responsive polymer composite based Lab-on-a-Chip (LOC) devices. LOC devices, also known as micro-total-analytical systems (microTAS) or microfluidic devices can amalgamate miniaturized laboratory functions on a single chip. This significant size reduction decreases the amount of required fluid volumes down to nano or pico-liters. The main commercial application of LOC devices is the biomedical fields. However, these devices are anticipated to make a technological revolution similar to the way miniaturization changed computers. In fact, medical and chemical analyses are predicted to shift from room-sized laboratories to hand-held portable devices.

This dissertation is divided into …