Treasures @ UT Dallas
Welcome to Treasures @ UT Dallas Institutional Repository, established in 2010. Treasures is a resource for our community to showcase, organize, share, and preserve research and scholarship in an Open Access repository.
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Recent Submissions
A Novel Immune-interactive Surface Coating Approach to Induce Implant Osseointegration in Diabetic Conditions
(2023-08) Arteaga, Alexandra 1989-; Rodrigues, Danieli; Summers, Joshua; Ferruzzi, Jacopo; Nielsen, Steven O.; Hoyt, Kenneth; Di Prima, Matthew; La Fontaine, Javier
Titanium (Ti) orthopedic devices are often used to restore the function of damaged bones.
However, reciprocal effects between implant surfaces and tissues can affect the success and
performance of the implant due to corrosion, micro motion, dislocation, infection, or the
inflammatory response of surrounding tissues. Additionally, diabetic patients receiving implants
exhibit higher rates of implant failure due to impaired osseointegration and systemic
complications compared to non-diabetic patients, which contribute to poor outcomes in
orthopedic treatments, such as fracture healing. Because there is an increasing diabetic
population that will require the use of implants, there is an urgent need to determine underlying
mechanisms of diabetes-induced poor osseointegration and bone repair.
Retrieved implants and in vitro testing of discs in simulated diabetic environments were first
analyzed to understand how diabetes affects Ti implant surfaces. All retrieved implants have
some degree of surface damage (pitting attack, discoloration, scratches, delamination, etc.).
Therefore, the goal of this dissertation was to develop a coating that mitigates failure modes and
improves the predictability of implants in immunocompromised conditions.
Two multifunctional dicationic imidazolium-based ionic liquids (IonLs) containing
phenylalanine (1,10-bis(3-methylimidazolium-1-yl)decane diphenylalanine) and methionine
(1,10-bis(3-methylimidazolium-1-yl)decane dimethionine) were first investigated as thin films to
prevent direct adsorption and temporarily immobilize exogenous proteins on Ti surfaces. The
selected protein for this study was High Mobility Group Box 1 (HMGB1), which has been
shown to be involved in the recruitment of inflammatory and mesenchymal stem cells to
implantation sites, contributing to healing and implant integration. The optimal IonL coating was
chosen based on in vitro and in silico analysis. It was demonstrated that HMGB1 is stable when
anchored by the IonL containing phenylalanine, which prevents protein denaturation from
surface adherence. However, HMGB1 is redox sensitive and exists in different isoforms (fully-
reduced HMGB1 (FR), a recombinant version of FR resistant to oxidation (3S), disulfide
HMGB1 (DS) and inactive sulfonyl HMGB1(SO)), that can each have distinct biological
functions in health and disease. Each isoform was applied to the IonL-Phe thin film and
implanted subcutaneously to assess the inflammatory effects of surrounding tissues in response
to the coating. From these studies, the 3S HMGB1 was selected as the most favorable with
regard to tissue healing, to be further applied to orthopedic implants in a model of open reduction
fracture fixation (ORIF) in tibias of diabetic rats. This coating conformation (Ti-IonL-HMBG1)
was then used in the ORIF model to assess the fracture healing and osseointegration potential in
diabetic and normoglycemic conditions. Overall, the results for the new coating pointed to
beneficial outcomes in fracture healing of diabetic rats, achieving healing parameters comparable
to non-diabetic rats. Altogether, this dissertation demonstrates the design and assessment of ionic
liquid and exogenous HMGB1 as an immunomodulatory coating to improve osseous healing in
diabetic conditions.
Properties of Blade-coated Transparent Conducting Oxide Sol-gel Precursor Films on Plastic Substrates
(2023-05) Turner, Gary George 1999-; Hsu, Julia W. P.; Quevedo-Lopez, Manuel; McCall, Kyle
The transparent conducting electrode (TCE) industry is dominated by indium-tin oxide (ITO)
films deposited on glass for rigid applications and flexible polymers such as polyethylene
terephthalate (PET) for flexible applications. These applications can range from liquid crystal
displays to light emitting diodes to perovskite solar cells, most of which require electrodes with
the maximum possible optical transmittance and the minimum possible sheet resistance. ITO
films are generally deposited on their substrates via chemical vapor deposition or sputtering, both
of which are low-throughput processes, on the order of 1 m/min web speeds or batch-processed
at slower rates.
This research presents a novel solution-deposition method for an alternative chemistry to TCE
films. Solution deposition is advantageous over chemical vapor deposition and sputtering
because it can be undertaken in an open air environment without much energy applied to coating.
The project focuses on doctor blade coating as an intermediate step between current batch-
processing methods such as spin coating and future roll-to-roll (R2R) compatible methods such
as slot-die coating, in order to understand the dynamics of meniscus coating.
The process entails synthesis, coating, and post-processing of indium-zinc oxide (IZO) sol-gel
precursor ink on PET substrates. The benefit of this chemistry is its flexibility compared to ITO,
its capacity for room-temperature solution deposition, and its decreased reliance on indium. The
compositional ratio of In:Zn is 7:3, whereas that of ITO is 9:1 In:Sn.
0.2 M IZO alone is not sufficient to support the desired electrical conductivity, however, so a
randomly oriented solution-deposited silver nanowire (AgNW) mesh layer is added to the IZO
layer on PET. This results in the architecture PET/AgNW/IZO that has shown promising results
in terms of transparency and conductivity.
It is shown in this research that the PET/AgNW/IZO architecture is capable of performing within
the range of figures of merit (FoMs) of commercially available PET/ITO and is processable at
approximately ten times the speed. In addition to a deep exploration of the mechanisms at play
during the blade coating process of each of these layers, this report includes a technoeconomic
analysis comparing the two architectures and the costs of each in order to establish that blade
coated PET/AgNW/IZO is less expensive to manufacture than PET/ITO is to purchase. This has
implications for the TCE industry as throughput demands grow higher and higher as our society
demands more high performance optoelectronics, and R2R solution processing is a suitable
alternative.
Performance Analysis and Scope of Residue Number System in Digital Computing and Hardware Security
(2023-05) Olee, Shakil Mahmud 1996-; Saquib, Mohammad; Chiu, Yun; Basu, Kanad
The Residue Number System (RNS) has become increasingly popular in digital signal
processing and cryptography due to its innate parallelism and inherent non-linearity. RNS
represents numbers as remainders when divided by chosen moduli and enables parallel
processing, leading to efficient arithmetic operations. However, it requires computationally
expensive conversions and careful selection of the moduli set to avoid precision loss and
deal with overflow issues. In the field of hardware security, RNS is an attractive proposition
because of its highly non-linear transfer function that makes it difficult for attackers to model
or predict the behavior of the system. In this thesis, the scope of RNS in both efficient
computing and hardware security has been analyzed thoroughly. The application of RNS in
building a fast throughput Multiply and Accumulate (MAC) block through parallel processing
has been demonstrated in a 65 nm CMOS process, where post-layout performance evaluations
of the proposed RNS MAC demonstrate a 17% improvement in latency with an area-power
consumption overhead of 12% when compared to the traditional binary MAC. Moreover,
the promising aspect of the highly non-linear RNS in building a secure PUF has also been
examined rigorously by carrying out ML attacks against different behavioral PUF circuit
configurations.
Bioinspired Surfaces for Super Liquid and Ice Repellency
(2023-05) Sarma, Jyotirmoy 1992-; Koeln, Justin; Dai, Xianming; Cui, Shuang; Lu, Hongbing; Xiong, Guoping; Bernal Montoya, Rodrigo
Surfaces with ultralow adhesion to liquids and solids are of great interest for both fundamental
research and practical applications, from passive removal of highly wetting liquids to anti-icing.
This dissertation aims to investigate and develop bioinspired methods for achieving super-
repellency and addressing issues related to the high adhesion of liquids and ice on surfaces. In
this dissertation, the limitations of the current state-of-the-art superomniphobic surfaces (rely on
air lubricant) and liquid-infused surfaces (rely on liquid lubricant) are discussed followed by the
proposal of a new design of superomniphobic surface, which mitigates the dependence on
stringed nanoparticles and can be easily converted into a liquid-infused surface with a simple
one-step process. Drawing inspiration from various bio-inspired design strategies, along with
liquid repellency anti-icing has been explored in broad aspects: (1) Delay of frost propagation
through the meniscus-mediated spontaneous movement of droplets on liquid-infused surfaces.
Surface tension forces generated by the hydrophilic oil meniscus of a large water droplet on a
hydrophilic liquid-infused surface efficiently pull neighboring tiny droplets with a diameter < 20
m from all directions, causing them to climb and coalesce. This creates a dynamic length
separation between water droplets and a neighboring frozen droplet, which eventually delays
frost bridging. This is supported by a theoretical model to characterize the dynamically changing
inter-droplet gaps. (2) A new design of quasi-liquid surfaces is demonstrated to address the
durability challenges of current state-of-the-art super-repellent surfaces in terms of liquid
repellency and ice adhesion. Inspired by cilia in human lungs, quasi-liquid lubrication is
achieved by grafting flexible polymer molecules on a flat solid substrate. The mobile polymer
chains behave like a liquid layer and significantly reduce the interfacial adhesion between the
substrate and ice, resulting in ultralow ice adhesion. (3) The adhesion mechanics of ice on
different substrates at high supercooling are studied. Due to a sudden drop in temperature from -
10 to -60ºC, ice cracking occurs and can be categorized as large, intermediate, and no cracks on
aluminum, glass, and polycarbonate respectively based on the thermal properties of the substrate.
A theoretical model is proposed to quantify the number of cracks formed at the ice-substrate
interface due to thermo-mechanical stresses. Finally, an analogy is made between the interfacial
cracks, total crack length, and the reduction in ice adhesion. Overall, this dissertation provides
insights into bioinspired design strategies for super-repellency, with potential applications in
liquid repellency and anti-icing.
Amazon’s Ring: How Smart Home Cameras Produce a Consumer Policing Model
(2023-05) Field, Jamie; Knight, Kim; Prieto, Rene; Banner, Olivia; Fischer, Anne Gray; Terry, Dean
Government, police and businesses deploy fear and terror to control the narrative surrounding the
politics of surveillance and increase their power over individuals’ everyday lives. As with
Foucault’s panopticon, in modern day surveillance, people are often unaware that they are being
watched, or if they are aware, they comply for the betterment of the community. Companies like
Amazon push the boundaries of acceptable surveillance methods with home cameras under the
guise of “keeping people safe,” and adopt new biometric technologies that their law enforcement
partners use against local communities as seen in Dallas/Fort Worth. According to David Lyon,
the new surveillance is “individualized and competitive” (Lyon 60). We must not forget the
active role of the subject regarding surveillance and its aggressive technologies. As subjects in a
rapidly advancing technological world, it is vital that we should learn to return the gaze and
counteract abusive surveillance methods like the Ring.