“A World of VICE” examines one case study—digital media company VICE Media—as an aperture into analyzing the material and affective politics of 21st century media cultures, industries, and politics. VICE’s visceral, “immersionist” journalistic style, which privileges experiential knowledge and appeals to affective engagement over other more informative approaches, has been cited as its own unique form of innovation in journalism, youth content creation, advertising, and digital business. This dissertation uses VICE as a mode for understanding key changes in the cultural landscapes, industry organizations, and visual ecologies of digital culture. Broadly, I argues that increasingly speculative capitalist practices have facilitated a far-reaching extractive economy geared toward monetizing and enclosing upon affective capacities. I use key moments in VICE’s tumultuous history as a lens for examining the widespread social and economic contradictions that characterize 21st century global politics and culture.

This project builds connections between a rising interest across journalism, information studies, and critical media and communication studies in “the affective politics of digital media” and vital critiques of platform power. It is methodologically informed by what critical cultural studies scholars have called “conjunctural analysis,” in which tracing the always-already contested terrain of a conjuncture involves mapping the connections between the material and affective dimensions of culture. The first thread—which engages closely with the material dimensions of VICE’s empire-building project—examines shifts in cultural and economic power sparked by the rise of digital technologies, platforms, and industries. The first and second chapter focus on unpacking the spatial and industrial contexts of VICE’s rise, zooming in on the intersections between creative economies and urban renewal (chapter one) and the “messy middle” of digital video economies that gave rise to a viral digital news bubble (chapter two). The second thread examines how these material dimensions inform and are informed by broader changes in the affective landscapes of digital media and digital culture. This thread zooms in on the connections between affective politics and digital culture in journalistic (chapter three) and documentary (chapter four) video cultures, particularly as cultural production becomes increasingly entangled with the commercial and data-driven interests of social media platforms. This dissertation contributes to critical work occurring in contemporary digital media and cultural theory, global media studies, media industries studies, and journalism studies.

The proximate mechanisms underlying foraging behavior in sea otters (Enhydra lutris) are relatively unknown despite decades of research focused on the biology and ecology of this top predator. Sea otters prey on infaunal or visually cryptic benthic invertebrates, but maintain a high rate of capture to consume a quarter of their body mass each day. Consequently, sea otter sensory systems have been shaped by selective pressures for accurate and efficient detection of prey location and assessment of prey quality. This dissertation describes a series of behavioral experiments with trained sea otters and anatomical studies from post-mortem sea otters to assess the visual and tactile capabilities of this species in the context of underwater foraging behavior. Chapter 1 focuses on the visual sense and potential adaptations for foraging in marine environments and low light. This material comprises quantitative and qualitative descriptions of pupil mobility, retinal photoreceptor distribution, and tapetal morphology to assess low-light sensitivity relative to previously demonstrated amphibious acuity. We find that sea otter pupils adjust in size to variable light levels and sea otter retinas retain features that enhance sensitivity in low light. However, pupillary dynamic size range and visual acuity in low light are limited relative to other marine carnivores, likely due to a smaller absolute eye size, non-specialized circular pupil shape, and a reliance on a narrow range of pupil sizes to adequately deform the lens to retain visual acuity under water. Given that sea otters forage successfully across a wide range of light levels and for buried prey, the conclusions from Chapter 1 motivated subsequent investigations of whether sea otter touch abilities are sensitive enough to compensate for the loss of visual focus in low light. The results presented in Chapters 2 are drawn from a comprehensive series of four experiments with a trained sea otter to directly measure in-air and underwater tactile sensitivity for paws and facial vibrissae. These studies provide a behavioral means to evaluate predictions based on previous research of sea otter brain and vibrissal morphology. We find that sea otter paw and vibrissal sensitivities are comparable to other tactile specialists, but paw-based touch is especially acute and comparable to human hands. Additionally, sea otter decision times were reliably less than 250 ms for paw and 500 ms for vibrissae, which suggests that sea otters can make fast and accurate decisions based on information received through touch. Chapter 3 builds on the behavioral results from Chapter 2 to investigate the density and distribution of sensory receptors and associated circulatory structures in sea otter glabrous (i.e., hairless) skin—paw pads, flipper digit pads, lips, and the rhinarium—and to link the degree of neural investment to differential sensitivity and use of these regions in observed sea otter behavior. We confirm the presence of two mammalian mechanoreceptor types—Merkel cells and Pacinian corpuscles—and find that their densities, as well as corresponding neural and blood supply, were highest in the paw digit tips and substantially lower in other glabrous skin. This pattern of increased neural investment is consistent with the areas of the paw primarily used for texture discrimination in Chapter 2, which suggests that the distal paw serves as a tactile fovea in sea otters. As a body of work, this dissertation combines structural and functional approaches to provide a more comprehensive assessment of the visual and tactile systems in sea otters. The findings from these studies not only contribute foundational knowledge about the sensory biology of sea otters, but also offer a mechanistic framework to interpret behavioral patterns and energy expenditure observed in wild sea otters across variable environmental conditions.

INTRODUCTION: Maternal body composition may influence fetal/neonatal body composition.OBJECTIVE: To investigate the relationship between maternal and fetal body composition. METHODS: Three cohorts of women were studied: healthy mothers, mothers with gestational diabetes (GDM), and otherwise healthy mothers with a growth-restricted fetus (FGR). MRI measured quantitative traits of maternal body composition (visceral adipose tissue volume (VAT), subcutaneous adipose tissue volume (SAT), pancreatic and hepatic proton-density fat fraction (PDFF)) and fetal body composition (abdominal SAT and hepatic PDFF). RESULTS: GDM fetuses had greater SAT volume than FGR fetuses and greater hepatic PDFF than FGR (280 [261, 295] vs. 220 [205, 235] mm3) and healthy fetuses (GDM 5.2 [4.2, 5.5]%, FGR 1.9 [1.4, 3.7]%, healthy 3.2 [3, 3.3]%). Fetal hepatic PDFF was associated with maternal SAT (r=0.47, p=0.02), VAT (r=0.62, p=0.002), and pancreatic PDFF (r=0.54, p=0.008). Fetal SAT was associated with infant birth weight z-scores (r=0.48, p=0.02). CONCLUSION: In this study, maternal adiposity and GDM status were associated with fetal hepatic fat.

Lignocellulosic biomass is an abundant, low-cost resource for the renewable production of fuels and chemicals. To unlock the potential of lignocellulosic biomass, the cellulose must be broken down into sugars before fermentation to produce ethanol, butanol, or other bio-based products. Unfortunately, lignocellulose is highly resistant to enzymatic degradation, necessitating high enzyme loadings that increase the cost of biofuels. The recalcitrance of biomass stems in part from the presence of lignin, a major component of lignocellulosic biomass. Lignin impedes enzymatic hydrolysis by non-productively binding cellulases and contributing to cellulase denaturation. Despite numerous studies documenting cellulase adsorption to lignin, the structural basis has not been fully elucidated and few attempts have been made to engineer enzymes for reduced lignin affinity.

In this work, we investigate and engineer cellulase adsorption to lignin and the resulting effect on hydrolysis of cellulose. The lignin inhibition of two homologous cellulases, T. reesei Cel7A and T. emersonii Cel7A, was found to differ significantly. In Chapter 2, we propose that differences in surface charge, stability, and glycosylation patterns may be the driving force/s behind the observed differences in lignin inhibition and we suggest engineering strategies for improving lignin tolerance of Cel7A catalytic domains.

Chapters 3 and 4 detail our efforts to investigate the mechanisms of cellulase lignin adsorption and engineer an enzyme with reduced lignin affinity using site directed mutagenesis of the T. reesei Cel7A carbohydrate binding module (CBM) and linker. Mutation of aromatic and polar residues on the planar face of the CBM greatly decreased binding to both cellulose and lignin, supporting the hypothesis that the cellulose-binding face is also responsible for the majority of lignin affinity. Cellulose and lignin affinity of the alanine mutants were highly correlated, indicating similar binding mechanisms for cellulose and lignin. CBM mutations that added hydrophobic or positively charged residues decreased the selectivity toward cellulose, while mutations that added negatively charged residues increased the selectivity. Mutating the linker to alter predicted glycosylation patterns greatly impacted lignin affinity but did not affect cellulose affinity. Beneficial mutations were combined to generate a mutant with 2.5 fold less lignin affinity and fully retained cellulose affinity. This mutant was not inhibited by added lignin during hydrolysis of Avicel and generated 40% more glucose than the wild type enzyme from dilute acid-pretreated Miscanthus. The mutations studied here inform engineering efforts of other homologous CBMs and will hopefully contribute to reducing the cost of biofuels.

The final chapter details the development of a high-throughput selection platform for engineering protease enzymes with new sequence specificity. Proteases are commonly used in research, industry, and medicine, and there is considerable promise for new proteases that could cleave at a user-specified sequence. Positive selection and counter-selection were combined to select a tobacco etch virus protease mutant with new substrate compatibility.

For decades, scientists have been fascinated by the ease with which viruses, seemingly simple life forms, evolve new feats of innovation. One viral innovation relevant to humans is gaining infectivity on a new host type. Although numerous instances of viral host-range expansion have been documented, we still lack the ability to predict them reliably. In part, this is because many factors affect whether a host shift will occur, ranging from molecular interactions to host behavior. To increase the tractability of this problem, scientists are beginning to ask whether viruses might vary in their innate evolvability, or capacity for adaptive evolution. I focused on the role of stability, here defined as thermodynamic stability, an intrinsic trait of viral proteins thought to enhance evolvability. Using the well-studied host-range expansion of bacteriophage λ, I first showed how mutations that confer expanded host range destabilize the receptor binding protein and allow it to assume alternative conformations with new binding activity. Then, I showed that among λ genotypes varying in stability, the most evolvable tended to be the most unstable, and the stable genotypes that did evolve gained destabilizing mutations. Instability promoted the evolution of new host range, in contrast to the widely cited consensus that stability enhances evolvability. I discovered one λ genotype that exhibited high stability and evolvability, but it grew poorly, suggesting a three-way tradeoff between stability, evolvability, and reproduction. This result led to another question: if traits that affect current fitness, like stability and reproductive rate, trade off with future evolutionary capacity, then which traits most influence the outcome of coevolutionary arms races between viruses and their hosts? I examined which traits influence λ’s ability to overcome host resistance and maintain infectivity on its coevolving host bacteria. The fast-reproducing, evolvable, but unstable genotype emerged most successful, suggesting that lineages that initially appear poorly adapted may give rise to progeny that persist due to their capacity to evolve. This work suggests that a positive, linear relationship between stability and evolvability does not hold in all scenarios, with important implications for predicting viral emergence and selecting genotypes for phage therapy.