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<p> Photoresponsive polymers can act as controllable drug delivery systems that may revolutionize ophthalmic drug delivery for disease treatment in the posterior segment of the eye. Localized, controlled drug delivery devices have significant therapeutic advantages for treating diseases of back of the eye by increasing patient compliance and maintaining therapeutic levels of drug in the tissue. Sustained-release delivery systems that respond to light/laser stimuli are under development to control the rate of delivery resulting in a tuneable treatment profile ideal for retinal diseases. The use of light as a crosslinking mechanism has the potential to create unique materials with controllable swelling, degradation and diffusion properties. </p> <p> This thesis investigates the synthesis and development of universal, graftable PEG-anthracene molecules and their applications in photosensitive alginate and hyaluronate (HA) "photogels". Anthracene undergoes reversible dimerization with wavelengths above 300 nm and de-dimerization/dissociation below 300 nm; due to its well-understood chemistry and symmetry, it was used as a starting point and proof-ofconcept for the synthesis of reversible dimerizing crosslinkers that may be generically grafted to different polymers to cause crosslinking/decrosslinking. After synthesis, watersoluble PEG-anthracene macromolecules were grafting via carbodiimide chemistry to the carboxyl groups along the polymer backbone of alginate and HA at various densities to create viscous liquids or gels with good handling properties. </p> <p> Light irradiation can be used to control the swelling and effective crosslinking density of the photogels which in tum can control drug delivery from photocrosslinked hydro gels as illustrated through the decrease or increase in the delivery of a variety of low molecular weight (<1000 Da) and high molecular weight (>10,000 Da) model drug compounds from both alginate and HA photogels with various light treatments. Novel loading mechanisms were developed through the loading of compounds into uncrosslinked gels followed by crosslinking 365 nm exposures to "lock" in the model drug compounds. Diffusion coefficients effectively compared the different systems showing increase exposures of 365 nm resulted in greater decrease in release of compounds demonstrating the ability to fine-tune release rates. Different formulations and control gels demonstrate a variety of different release profiles. The photogels were valuable long-term controlled release systems (>80 days) that also demonstrate high cytocompatibility when grown with ophthalmic cell lines. </p> <p> Novel photoresponsive biomaterials for smart delivery of therapeutics which use light-controlled crosslinking and decrosslinking mechanisms have been developed. The PEG-anthracene graftable photocrosslinkers show the ability to introduce photocontrolled crosslinking into hydrogel systems. While anthracene as the photodimerizer and alginate and HA as the bulk materials are used as a proof-of-concept in this work, this grafting system can be further manipulated to include new photosensitive dimerizers and other applicable polymers. The ability to use light stimuli to control release rates in a continual fashion, rather than having delivery that is strictly on or off, is a valuable finding that may lead to the development of drug delivery systems that can be catered towards individuals and the progression of their disease. </p> / Thesis / Doctor of Philosophy (PhD)

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This thesis will explore, both generally and very specifically, the role of biomaterials in drug delivery and tissue engineering applications. A novel therapeutic conjugate to treat dry eye disease using hyaluronic acid and sulfadiazine was created and tested using a benzalkonium chloride induced dry eye model. Thermoresponsive hydrogels based around poly(n-isopropylacrylamide) were synthesized to create a potential in situ gelling cell scaffold for cell delivery to the subretinal space. Finally, a mucoadhesive micelle was developed as a platform delivery system to increase bioavailability of drug in anterior segment therapeutics. / Thesis / Doctor of Philosophy (PhD)

Developing a drug delivery vehicle that can control the release kinetics of a therapeutic drug on demand has great potential to improve health by allowing health care professionals to maintain the drug concentration in its therapeutic window and increase the efficiency at which treatment is administered. On-demand release can be triggered by a range of stimuli including magnetic, radiation, and ultrasound activation. Of the three, ultrasound is the only one indiscriminate of the chemical properties of the material and is the most widely available clinically, which makes it versatile and applicable for many systems. However, existing strategies that use ultrasound as a release stimulus either pop the microcapsules altogether (enabling no subsequent effective control over the kinetics of drug release) or require continuous ultrasonic administration (typically impractical in a clinical setting), both of which are suboptimal. Overcoming at least of these shortcomings would vastly improve on the technology. In this thesis, microcapsules with a complex shell were fabricated using a modified electrohydrodynamic approach named immersion coaxial electrospraying, which allowed for an increased polymer loading in the shell and improved manipulation of microcapsule size. The complex shell structure of the microcapsules incorporated silica microparticles that acted as corks plugging pores between the inside and outside of the microcapsule. The modified microcapsules were shown to release their payload in the presence of a focused ultrasound signal, while uncorked microcapsules do not release. Release kinetics were shown to be adjustable based on the number of corks initially present in the shell of the microcapsule material. Altogether, the cork-shell microcapsules fabricated in this thesis show promise as a tunable on-demand drug delivery vehicle that is able to better control release compared to conventional ultrasound triggered microcapsules. / Thesis / Master of Applied Science (MASc) / This thesis focuses on the fabrication of complex microcapsules that can be deliver therapeutic drugs on-demand using ultrasound waves. These microcapsules are composed of a water-based core and a biologically inert shell into which particles are embedded. Upon the application of ultrasound, these embedded particles (like corks on a bottle) are popped out to release the “corks” from the shell, creating pores from which the drug in the microcapsule core can be released. In the absence of ultrasound signals, the microcapsules do not release any of their contents, making these effective for “on-demand” release. These microcapsules are made using a modified process based on electrospraying which allows very precise control over the microcapsules’ physical properties, incorporating a key modification that overcomes an inherent issue with the general technique. These microcapsules also improve on currently used ultrasound triggered drug delivery systems by requiring shorter periods of ultrasound and/or enabling better control over the dynamics of drug release following the ultrasound pulse.

The purpose of this exploratory study was to determine which of the three training-delivery systems is the most frequently selected by training professionals in Virginia and which training methods are selected to support the chosen delivery systems. The study also examined the extent to which internal and external factors contributed to the selection of the delivery systems and the training methods. Qualitative research methodology was employed in analyzing the results of 12 in-depth interviews with purposively selected training professionals in Virginia in order to answer the research questions. This study found that (a) the training professionals chose instructor-led classroom for 46% of their programs, the blended method for 32%, and online for 22%; (b) they used a wide variety of training methods to support the program objectives and meet the audience’s needs; and (c) external factors more frequently impacted selection decisions than did internal factors, but one internal factor that impacted selection decisions was the training professionals’ understanding of instructional systems design. The external factors that had the greatest impact on the training system chosen were workplace constraints such as immediacy and scalability and the size and geographical dispersion of the audience. That is, for large and/or dispersed audiences coupled with time constraints, the online delivery system was chosen most often. Likewise, mandatory programs were most likely to be offered online. The following conclusions were drawn: (a) a shift is taking place from instructor-led-classroom delivery to blended delivery, (b) instructor-led classroom incorporates methodologies that extend beyond the lecture format, (c) companies are using emerging technologies in training and development, and (d) training and development continues to add value to the workforce, which is a powerful competitive advantage. / Ph. D.

Through a systematic exploration of varied but interconnected landscapes, this dissertation investigates how drone technology not only reshapes individual sectors but also interlinks them, fostering a cohesive advancement toward a more efficient and technologically integrated future. By focusing on drone applications in last-mile deliveries, medical supplies, and aerospace innovations, this work contributes robust insights into the strategic adoption of drone technology, offering guidelines for policymakers, industry stakeholders, and academic scholars aiming to navigate and leverage the potentials of this groundbreaking technological frontier. Each essay within this dissertation builds upon these themes, presenting in-depth analyses and discussions that bridge theoretical knowledge with practical applications. By addressing specific challenges and opportunities within each sector, this comprehensive study contributes to academic research. It provides actionable insights for practitioners and policymakers engaged in the cutting-edge realms of logistics, healthcare delivery, and aerospace development.

Information system development projecs are often considered a costly and uncertain process were projects often exceed the scheduled time and budget. By continuously integrating source code and do regular builds problems can be discovered almost directly and thus minimizing the cost to fix them. In this qualitative study we have focused on which challenges a large public organization who cooperate with an external provider can face when adopting continuous integration and continuous delivery. We have interviewed six employees within the organisation and two employees from the external provider, who are all in some way connected to the software development process. The results showed that our interviewees are interested in agile software development and to be able to deliver high quality software continuously. We also found that the software development process is complex and has a lot of barriers and handovers that slows the process down. Our conclusion is that the organization needs to change their approach to software development. To achieve this the organisation needs to adopt Devops, which means erasing the barriers between development and operations.

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