In this article, I will argue that ghosts are used, in two very different contexts and cases, as ways to represent and discuss anxieties about the advances of science and the uses of technology, at the same time that they express a cautious fascination with these unstoppable advances. This concern with the ability of ghosts to move and adapt to technological change is not only about what happens in the films but is also related to what happens outside the films, that is, the viral expansion of ghosts stories and filmic narratives as ways to talk about social and political issues. I will work primarily with two short stories by Uruguayan writer Horacio Quiroga, “The Specter” and “The Puritan”, that I will place in dialog with two Japanese movies, The Ring by Hideo Nakata and Pulse by Kiyoshi Kurosawa, tracing their possible connections and interpolations.

Immune checkpoint blockade therapies constitute one of the major advances in cancer treatment. Despite the long-lasting responses observed in a wide range of tumor types, the majority of patients do not respond or relapse shortly after. In order to increase response rates, we need to better predict patients that would benefit from the treatment as well as identify resistance mechanisms to find novel treatment strategies. However, the interplay between the immune system, the cancer cells and the tumor microenvironment is complex and dynamic, rendering the understanding of resistant mechanisms particularly challenging.

Lack of immune cell infiltration constitutes one of the main mechanisms of primary resistance to checkpoint blockade. The absence of T cells on the tumor margin leaves the therapeutic targeting of immune checkpoints ineffective. Interestingly, cancer cell-intrinsic mechanisms could actively participate in the process of immune evasion and importantly, could be pharmacologically targeted to reverse immune exclusion. The finding of actionable molecules that increases T cell infiltration in the tumor could be used in combination with PD-1 blockade, in order to reverse adaptive immune resistance.

Here, we characterized the tumors of melanoma patients treated with PD-1 blockade. Our analyses further validated lack of immune cell infiltration as one mechanism of resistance. Importantly, we identified PAK4 as a novel and actionable target that is enriched in biopsies with poor immune infiltration and lack of response to PD-1 blockade. We show how genetically and pharmacologically that inhibition of PAK4 increases immune cell infiltration and improves checkpoint blockade therapy in several in vivo mouse models. We further characterized the impact of inhibiting PAK4 expression. The transcriptomic profiles of PAK4 KO tumors revealed the profound effect that has on the tumor microenvironment, particularly in the genes related to the extracellular matrix and blood vessel formation. This work serves as an example of how direct changes in cancer cells impact the tumor microenvironment and influence the anti-tumor immune response. Importantly, this work also provides the scientific rationale for a novel treatment strategy to combine PAK4 inhibitor with checkpoint blockade.

While U.S. schools grapple with persistent racial inequities, we argue that niceness, a socioemotional way of being that privileges whiteness, regularly impedes “equity” and “diversity” efforts in K-12 and teacher education settings. In the Midwest, niceness is uniquely rooted in a historical “obsession with public civility” (Cayton & Gray, 2002) that advances whiteness through a “demure white supremacy” (Cleveland, 2021), particularly in education. Here, the authors theorize Midwestern educational niceness, a regionally produced and enacted phenomenon “nicely” instantiated by the predominantly overwhelmingly white, Midwestern teacher workforce that actually stymies equity efforts. The authors conceptualize the ways whiteness through niceness works through a number of other phenomena including color evasiveness (Annamma et al., 2017; Bonilla-Silva, 2003), white fragility (DiAngelo, 2018), and emotionalities of whiteness (Matias, 2016). Countering the insidiousness of Midwestern educational niceness will require a recognition that this regional form of niceness and equity are incommensurate.

Energy fixed by primary producers supports the vast majority of life on earth. The giant kelp Macrocystis pyrifera is the largest marine alga in the world and supports one of the most productive ecosystems on earth. Carbon fixed by Macrocystis pyrifera on temparate rocky reefs not only provides essential habitat for an entire community of associated species, but also provides carbon subsidies to nearby ecological communities. Net primary productivity (NPP) is often used to quantify energy fixation by autotrophs, and researchers often measure NPP by summing the incremental increases in biomass and foliar losses. While the processes governing incremental increases in biomass have been well studied, the processes that drive the loss of foliar biomass are poorly understood.

The main theme of my research is the investigation of the drivers that regulate the lifespan of foliar biomass of giant kelp beds near Santa Barbara, California, USA. Tissue lifepspan in marine macroalgae has not received much attention from either plant ecologists or algal ecologists, despite its potential importance to the dynamics of primary productivity. Macrocystis is an ideal species for investigations on tissue lifespan in macroalgae for two main reasons. First, it is well studied and much of its biology is already known, and second, Macrocystis is locally abundant, grows fast and turns over frequently. In addition, due to relatively benign environmental conditions for Macrocystis growth, the coastal margin along the Santa Barbara Channel is an ideal location to study intrinsic properties in the absence of extreme environmental forcing (such as frequent temperature spikes and severe storm events) that could overwhelm potentially important patterns.

I investigated drivers that regulate frond and blade lifespan in Macrocystis, and the consequences of limited frond and blade lifespans. The first chapter is a long-term, multi-site analysis of frond lifetimes and exploration of internal and external drivers that could affect frond lifetime. This study provides broad spatial and temporal scope and identifies progressive senescence as an important driver of Macrocystis biomass dynamics. The second chapter employs a more focused field study to investigate whether spatial variability in light within a kelp forests affects lifespan, size, thickness, nitrogen content and pigment content of Macrocystis pyerifera blades in ways that are predicted by theory developed to predict leaf traits of vascular plants. The last chapter is a mathematical model of the system, which I parameterized with field data, to explicitly quantify the loss of blade tissue via erosion and quantify the amount of biomass not captured in traditional surveys of net primary productivity.

I found that the natural course of progressive senescence in fronds can explain much of the variability in frond loss throughout a typical year in a Santa Barbara kelp bed, that kelp blades that have more access to light have shorter lifetimes (as predicted by leaf lifespan theory), and that ignoring the sub-lethal blade area losses can result in significant underestimates of net primary productivity. I believe that internal regulation of tissue turnover is an important mechanism by which giant kelp maximizes carbon gain in a changing environment and that adaptations that increase photosynthetic efficiency may be an important factor in the widespread success and dominance of Macrocystis.

In Chapter 1, I analyze firms' misallocation through the output distortions channel, using a production-based asset pricing model as a framework. In the model, alpha measures the firm's ability to choose technologies to adapt to exogenous shocks. I find in the cross-section of the test portfolios the estimated curvature parameter alpha is more than two times the original value obtained in Belo (2010). This implies misallocations reduce the firm's ability to respond to the different states of nature. I calibrate and solve the model in the special case of a single representative firm. I find that the impact of misallocation on firm value, production, capital, investment, and investment return is larger when firms' ability to adapt to exogenous shocks is reduced. This indicates that firms may be less agile to adapt across states of nature and provides more evidence of the detrimental effect of misallocations.

In Chapter 2 (with Denis Mokanov and Danyu Zhang), we document several facts about equity analysts' earnings expectations: (1) consensus earnings expectations underreact to news unconditionally, (2) the degree of underreaction declines during high-volatility periods, and (3) the degree of underreaction declines over our sample. To account for these findings, we develop a simple model featuring time-varying inattention. We show that our model is able to account for the unconditional profitability of momentum, momentum crashes, and the diminishing profitability of momentum over our sample. We propose a trading strategy that mixes short-run and long-run momentum signals and show that the mixed momentum strategy outperforms the conventional momentum strategies. Finally, we use a machine learning algorithm to estimate the predictable component of earnings surprises and construct a portfolio that is long (short) on stocks with excessively pessimistic (optimistic) earnings expectations. The resultant trading strategy generates an annualized Sharpe ratio of about 1.16 and its returns are not explained by popular factor models.