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The fashion industry struggles to address the waste accompanying overconsumption. Packaging, an inherent component of purchases (particularly in online settings), poses a particular dilemma. Current endeavors to decrease the environmental harm of packaging may only be suited to particular companies and can be expensive and time consuming to develop. Furthermore, products or packaging marketed as environmentally friendly are often associated with a price premium. Without a perceived personal benefit, consumers often forgo their sustainable values, discouraging development of sustainable initiatives. Prospect Theory positions that individuals tend to take different action based on the gain or loss frame. Literature suggests that references interact with frames, producing different results. Therefore, this study uses a 2 (frame: gain/loss) x 2 (reference: personal/societal) x 2 (green consumer value: high/low) mixed method online experiment in which consumers were shown one of four message combinations and offered the choice of no poly bag and a polybag. Analysis revealed that while the message did not have a significant effect on packaging selection, 74.73% fewer polybags were used because the option was present. Multiple 3 way ANOVAs revealed that brand attitude and purchase intention were affected by frame; frame and reference interacted to affect attitude towards the packaging initiative and brand attitude; and that green consumer values acted as a moderator in certain cases. Overall, this study provides a starting strategy for packaging initiatives and outlines message architecture to better promote sustainable behavior and positive attitudes for customers with both low and high green consumer values.

In urban streams, contaminants such as antibiotics, ARGs, nutrients, and metals, co-occur with anthropogenic activities. These toxicants can have a profound effect on microbial community composition, which may, in turn, affect microbial community function. Such results suggest that the composition and function of microbial communities are consequences of their response to environmental stimuli. However, the differing physiological responses of microorganisms to environmental stressors suggests that community structure may be an important factor driving the community's functional responses to avoid or reduce the effects associated with physiochemical changes in the environment. With the projected increase in concurrent environmental stressors associated with the anthropogenic activity, there is a need to understand how microbial communities respond to compounded stressors. The overarching question for my dissertation is: how does chemical stress (in the form of heavy metals) interact with other environmental factors (including hydrologic conditions and nutrients) to impact microbial community structure and function in streams? To address this question, I utilized a combination of trait-based molecular approaches in tandem with biological and chemical field measurements and laboratory experiments. I looked at how microbial, specifically bacterial and diatom, community composition, structure, and function were affected by different stresses that are found within urban streams.

We first explore the topology of liquid crystals and look at the fundamental limitations of liquid crystals in confined geometries. The properties of liquid crystal droplets are studied both theoretically and through simulations. We then demonstrate a method of chemically patterning surfaces that allows us to generate periodic arrays of micron-sized liquid crystal droplets and compare them to our simulation results. The parallelizable method of self-localizing liquid crystals using 2D chemical patterning developed here has applications in liquid crystal biosensors and lens arrays.We also present the first work looking at colloidal liquid crystals under the guise of thermophoresis. We observe that strong negative thermophoresis occurs in these systems and develop a theory based on elastic energy minimization. We also calculate a Soret coefficient two orders of magnitude larger than those present in the literature. This large Soret coefficient has considerable potential for improving thermophoretic sorting mechanisms such as Thermal-Field Flow Fractionation and MicroScale Thermophoresis.The final piece of this work demonstrates a method of using projection lithography to polymerize liquid crystal colloids with a defined internal director. While still a work in progress, there is potential for generating systems of active colloids that can change shape upon external stimulus and in the generation of self-folding shapes by selective polymerization and director predetermination in the vain of micro-kirigami.

We have presented the results of various experiments on several central ring substituted bent-core liquid crystals. We have synthesized a bent-core molecule that exhibits a nematic phase and is functionalized for future use in a liquid crystalline elastomer. Various experimental techniques were used to characterize properties such as smectic-like clusters in the nematic phases and piezoelectricity of polymer composites. We provide the detailed results and analysis of the SAXS measurements. The SAXS measurements were useful in analyzing the behavior of the smectic-like clusters that exist in the nematic phase of many bent-core molecules. The clusters have been shown to exist over a wide range of temperatures. We showed that the SAXS measurements agree with previous Cryo-TEM experiments on the three-ring bent-core compounds. We also compared the cluster behavior in two different materials - one with a smectic phase below the nematic and one without. We have found that, as expected, the smectic clusters show more pre-transitional behavior in the material with a smectic phase. Additionally, the clusters, just like the smectic phases of bent-core molecules, likely exhibit polar order. This could be the origin of the piezoelectric and flexoelectric responses found in some bent-core nematics. Addtionally, some of the bent-core molecules form a relatively unstudied phase called the X phase. It is shown to be optically isotropic and ferroelectric, and therefore, piezoelectric. A polymer composite was made from one of these materials. The material showed a piezoelectric response that was in agreement with previous converse piezoelectric measurements under static (DC) fields. It was shown to be comparable to commercially available piezoelectric ceramics. However, under oscillating forces of more than a few hertz, the piezoelectric response dropped off significantly likely due to stiffening of the polymer under oscillating strain with increasing frequency.

Blue phases (BP) are phases of chiral liquid crystals formed by lattices of double-twist cylinders with corresponding lattices of disclination lines. The conditions under which such an arrangement is energetically favorable generally occur in only a narrow band of temperature ranges, commonly less than 2C. Several methods have been devised to expand this range, notably polymer stabilization or nanoparticle stabilization. In addition, there is interest in using unconventionally shaped liquid crystals to form blue phases as molecular biaxiality is expected to help stabilize the phase. Here, we explore the potential of bent-core liquid crystals in creating stable blue phase materials with broad temperature ranges. It is known that the presence of achiral bent-core molecules in a chiral nematic material can induce blue phases where none were previously observed, and that liquid crystal dimers with a flexible center can create broad-temperature blue phases. Here we develop broad-temperature blue phase materials using bent-core nematic liquid crystals and chiral dopants, resulting in the first known example of a broad-range BPIII. Additional methods of phase stabilization are utilized in an attempt to increase the temperature range of the phase to encompass room temperatures.

We present results from experiments that focused in the following two areas: characterization and evaluation of lyotropic liquid crystal matrices as potential model membrane systems and using O2 as a paramagnetic probe of membrane immersion depth by NMR. Lyotropic liquid crystal structural studies focused on characterization of the structure of the isotropic bicelle as either a spheroidal mixed micelle or disc structure. Measurement of the extent of intermixing of the two principle phospholipids components of the system, DMPC and DHPC supported the disc structure of the isotropic bicelle. We also evaluated five materials known to form lyotropic liquid crystals, three dyes cromolyn, blue 20, and violet 27, a metal polymer V2O5, and a biopolymer, 2-isopropyl cellulose for their ability to align in the static field of the spectrometer. Of these materials, the cromolyn LC proved the best candidate as a host liquid crystal matrix for weak alignment studies. O2 was used as a paramagnetic agent to determine membrane immersion depth. The paramagnetic effects of the O2 molecule on nuclear spins are increases in relaxation rates and chemical shift perturbations, both of which are short range in nature. Additionally, O2 molecules assume exhibit an approximately Gaussian distribution across a lipid bilayer, with the highest concentration at the center of the membrane. By measuring changes in chemical shift perturbations and nuclear relaxation rates, we were able to determine the immersion depth of individual atoms of lipids, small peptides (indolicidin), and the large membrane protein diacylglycerol kinase (DAGK). We also determined that a dipolar interaction was responsible paramagnetic relaxation rate enhancement, while chemical shift perturbations were due to a contact interaction. In addition, O2 proved useful for determining which amino acids involved in the binding interaction of two water soluble proteins, the Fc fragment of an immunoglobin protein and its binding ligand, a fragment of protein A from S. aureus.