This research investigated both cognitive and affective influences of alternative color combinations in a search task paradigm. The effects of re-mapping the existing, comparatively arbitrarily color codes of baggage X-ray images, were explored. Alternative color-codes were evaluated for improving the economy of visual search in X-ray baggage screening. Using a 2 x 2 between-groups design, the perceptual aspects of color-codes varying in degree of visual agreeability (accordant or discordant) and color contrast (high or low) were examined in terms of effectiveness (detection accuracy) and efficiency (reaction time). Three hypotheses were put forth; two postulated main effects for color contrast and for visual agreeability, and a third postulated an interaction. Additionally, for comparison purposes, a fifth group of participants was presented with a stimulus condition that represented the current industry standard for colorizing X-ray images. Out of 100 volunteers, data were usable for 95 participants who had been randomly assigned to one of five conditions. All participants were exposed to the same screening task. The screening task required participants to view 153 X-ray images in random order. Of these images, 36 contained a single threat item (knife, scissor, gun) among clutter. Analyses of variance revealed significant differences between conditions with respect to detection accuracy. Implications are that high-color contrast improves detection accuracy; specifically with respect to correct rejections, and that this effect on performance can be moderated by psycho-emotional mechanisms. Specifically, the impact of color-contrast was significantly more pronounced under conditions of accordant color combinations. Theoretical underpinnings and applications to other domains are discussed.

This dissertation is divided into two main sections describing major portions of my Ph.D. research: (1) development of two enzymatic assays for identifying inhibitors of SARS-CoV-2 RNA dependent RNA polymerase (RdRp) and the associated proofreading exonuclease complexes, two key enzymatic activities of SARS-CoV-2, the virus responsible for the COVID-19 pandemic and (2) the design and implementation of four novel single-color fluorescent DNA sequencing by synthesis (SBS) methods, including the synthesis of many of the key nucleotide analogues required for these studies. In response to the COVID-19 pandemic, the first part of my research is focused on the discovery of potential therapeutics for combating coronavirus infections. Chapter 1 describes the identification of several polymerase and exonuclease inhibitors for SARS-CoV-2 using novel mass spectrometry-based molecular assays. SARS-CoV-2 has an exonuclease complex, which removes nucleotide inhibitors such as Remdesivir that are incorporated into the viral RNA during replication, reducing the efficacy of these drugs for treating COVID-19. Combinations of inhibitors of both the viral RdRp and the exonuclease could overcome this deficiency. Chapter 1 reports the identification of hepatitis C virus NS5A inhibitors Pibrentasvir and Ombitasvir as SARS-CoV-2 exonuclease inhibitors. In the presence of identified exonuclease inhibitors, RNAs terminated with the active forms of the prodrugs like Sofosbuvir, Remdesivir and Favipiravir were largely protected from excision by the exonuclease, while in the absence of exonuclease inhibitors, there was rapid excision. Viral cell culture studies also demonstrate significant synergy using this combination strategy. This study supports the use of combination drugs that inhibit both the SARS-CoV-2 polymerase and exonuclease for effective COVID-19 treatment. Chapters 2-6 describe the single-color DNA SBS studies. Chapter 2 provides essential background on the structure of DNA, the DNA polymerase reaction, and several key DNA sequencing technologies, with an emphasis on the design of nucleotide analogues for the DNA SBS approach. Chapter 3 delineates a one-color fluorescent DNA SBS method based on a set of nucleotide reversible terminators (NRTs) comprising two orthogonal cleavable linkers, one fluorescent dye and one anchor. Chapter 4 describes a one-color hybrid DNA sequencing approach using a set of dideoxynucleotide analogues bearing two orthogonal cleavable linkers, one fluorophore and one anchor as well as a set of unlabeled NRTs. By introducing a pH responsive fluorophore into the design of nucleotide analogues, Chapter 5 demonstrates a novel type of single-color DNA SBS method using a set of NRTs comprising one pH-responsive fluorescent dye or one non-responsive fluorescent dye tethered with one cleavable linker. Chapter 6 presents another option for the single-color DNA sequencing technique using a set of deoxynucleotide analogues comprising the above pH responsive or non-responsive dyes tethered with a cleavable linker, along with a set of unlabeled NRTs. The one-color SBS approaches have the potential for higher sensitivity, miniaturization and cost effectiveness compared with four-color SBS methods. Finally, Chapter 7 summarizes the SARS-CoV-2 antiviral drug discovery and one-color sequencing techniques and discusses potential follow-up research on these projects.

Children diagnosed with Attention Deficit Hyperactive Disorder (ADHD) are often secluded from society, as the condition is perceived to be a defect. These children constantly fidget, move, lose track of time, and forget to complete tasks, leading them to struggle within existing social environments. Additionally, in Qatar there is a need to educate society about ADHD. This research explores wearable solutions that alter behaviors through physical interactions and sensory engagements. In response to the challenges faced by ADHD, Qatari traditional attire has been customized to support children with time management, and communication between child, parent, and society. Additionally, these wearables challenge Qatari perspectives surrounding existing health conditions in Qatar. Design outcomes consists of clothing elements, driven and shaped by the experiences of ADHD children, their physical behavior, their senses like touch, smell and sight. It addresses the daily conduct of the ADHD child, and the relationship of the child and parent. By challenging existing norms and analyzing the Qatari traditional clothing (the Thobe, the Abaya and the Prayer Bead), design outcomes have been realized by experimenting and playing with materials, prototyping and 3D printing on fabric. Existing functions of zippers, pockets, beads, cuffs and technical construction of the outfit have been redesigned and reconstructed.