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A Genetic Modifier Attenuates Mistranslation Induced Neurodegeneration
No full textA spontaneous missense mutation (sticky; sti) in the editing domain of the mouse alanyl aminoacyl tRNA synthetase (AarsA734E) gene results in progressive cerebellar Purkinje cell degeneration on the C57BL6/J background stemming from Ser-tRNAAla mischarging. Mischarged Ser-tRNAAla leads to misincorporation of serine in the place of alanine, protein misfolding, and formation of ubiquitin-positive protein inclusions in Purkinje cells. Inclusion formation and degeneration of Purkinje cells in mutant mice does not occur in most F2 mice from a cross of B6J.Aarssti/sti to CAST/Ei mice, demonstrating, the susceptibility of this phenotype to genetic background. Positional cloning found that degeneration of many, but not all, Purkinje cells is due to a hypomorphic mutation in Ankrd16, which normally prevents mischarging of tRNAAla, in the C57BL6/6J genetic background. However, the identities of the additional modifier genes in CAST/Ei mice remain unknown. I determined that one of the additional modifiers, referred to as Msti-2, further attenuates Purkinje cell death in Aarssti/sti mice and resides within a 48.2Mbp region on Chromosome 2. These studies describe a rescue phenotype and highlight a candidate genomic region that influences Purkinje cell loss in the presence of the sticky mutation
Alter-narratives of Manong and Manang History: Memory, Photography, and Archives in California’s Pajaro Valley
Get PDFThis dissertation is the first comprehensive study of Filipino American history in the Pajaro Valley. The region has been a key node for Filipino American history since the early twentieth century, serving as a home and stopover for laboring migrants along the Pacific seaboard. However, Filipino presence in the Pajaro Valley has been narrowly documented, long overshadowed by the historiographical linchpin that is the 1930 anti-Filipino Watsonville race riots.Using analytical methods at the intersection of Asian American history, oral history, public history, visual studies, and critical archival studies, I argue that Filipinos in the Pajaro Valley create personal, familial, and community alter-narratives that transform historical knowledge. I define alter-narratives as individual and collective accounts that are consciously crafted to reflect different audience contexts. I use it to encompass a multitude of ways and degrees to which Filipino migrants and their second-generation descendants delineate their personal and historical experiences. I examine novel archival sources collected during five years of collaboration with the Tobera Project— a grassroots organization made up of descendants of the first Filipino settlers to the region—and Watsonville is in the Heart (WIITH), a community-engaged partnership between the University of California, Santa Cruz and the Tobera Project.In addition to centering the Pajaro Valley as a nexus for Filipino American history, this dissertation makes three more historiographic contributions. First, with its focus on photographic and archival alter-narratives created by Filipino migrants who arrived in the US between the 1920s and 1940s, I bring light to everyday tactics of survival and self-fashioning in the face of racism and exclusion. Second, I highlight the second-generation descendants— a group who has been elided in most public and scholarly accounts of Filipino American history. Through discussion of their archival, public history, and advocacy work, I show that descendants actively shape historical understandings of their relatives and their community. Finally, my interdisciplinary approach and my use of community-engaged research methods offers an innovative model for historical inquiry into migrant communities in the United States. I show that Filipino migrants and their descendants remake common narratives of the Pajaro Valley and Filipino America
A Multimodal Analysis of the Effects of Aging and Sleep Deprivation on the Brain and Periphery
Get PDFAging and sleep deprivation are two major, systemic stressors that impact both cognitive function and immune regulation. This thesis investigates how aging affects recognition and spatial working memory (Novel Object Recognition and Y-maze), while independently also examining the impact of enriched-environment sleep deprivation (EESD). Behavioural data was paired with in vivo two-photon imaging of dendritic spines, immunohistochemical investigation of microglia density, and multiplex cytokine assays in both the periphery and brain. Results showed that although aged mice did not exhibit pronounced behavioural deficits, they presented elevated microglia density in cortical regions, higher rates of dendritic spine elimination, and distinct cytokine changes suggesting early molecular changes that precede overt symptoms. Similarly, while EESD did not impair performance on memory tasks in young mice, it significantly increased spine elimination and triggered tissue-specific changes in cytokine levels. Together, these findings underscore the subtleties of age-related and sleep-loss-induced modulations and highlight physiological and molecular changes that occur before detectable behavioural deficits
Ever Bigger: The Social Worlds of the Megaship
No full textThis dissertation examines economies of scale in the global capitalist system. Its central object is the megaship: a large, ponderous oceangoing vessel that stitches together the arteries of world trade by carrying vast quantities of containers, crude oil, and bulk cargoes. As an analytical object, the megaship is a bundle of contradictions. From one angle, it connotes technical efficiency, canny cost-savings, smooth logistical planning, and the vitality of commerce. From another angle, it suggests instead comic excess, pollutive waste, investment opulence, and the invisibility of exploitation in the maritime world.
The dissertation’s overarching argument is that the economies of scale encoded in the hull of megaships are intimately tied to the creation and transformation of social worlds. I show that the proliferation of massive ships in the second half of the twentieth century was not a matter of value-neutral technological progress or of the increasing optimization of unit costs. Instead, I offer a perspective on the rise of megaships that stresses upheaval and contestation across far-flung geographies connected by capitalism’s maritime element.
This is a work of political economy informed by maritime economics and a work of history informed by critical geographies. In four chapters, each covering a distinct theme within the world shipping industry, I move through archival material, economic theory, forgotten secondary literatures, and obscure jurisprudential debates in order to unfurl the megaship’s twentieth century story.
The claims of the chapters are as follows. First, I examine the political conjuncture of Third Worldism in the long 1960s, finding that the development of merchant marines was a crucial aspect of autonomous nation-building after the advent of formal decolonization, and that economies of scale in shipping snuffed out such hopes for true economic independence. Second, I look at the unusual legal institution known as “flags of convenience,” finding that, in order to attain the labor cost-savings that could sustain a global megaship fleet, jurists had to gradually and unevenly make wholesale changes to international maritime law, so that big ships might become floating zones. Third, I examine the role of supertankers in the global petroleum economy, finding that the leaps in tanker innovation were quite literally pegged to the price of oil and the conquering of distance across shifting geographies of oil production and consumption. Fourth, I investigate the high-stakes trading of bespoke derivative financial instruments for hedging risk on volatile freight rates, finding that, in the maritime world, the slow, inflexible, and costly megaship is, paradoxically, the most effective risk-management device available
Improvisations Under Empire: Phillipine Lives and Negotiations at the 1904 Philippine Exposition
No full textIn 1904, more than 1,100 Filipinos traveled to St. Louis, Missouri, to participate in the Philippines Exposition at the Louisiana Purchase Exposition, an event designed by U.S. colonial officials to display the islands’ peoples, resources, and progress under American rule. Organized into ethnological exhibits in the form of villages, classrooms, and performance spaces, these exhibits presented Filipinos to American audiences through a racialized hierarchy that juxtaposed “civilized” lowlanders with “non-Christian” upland groups, and educated women with supposedly primitive counterparts. The Exposition was intended to showcase the benefits of U.S. tutelage and to legitimize the ongoing occupation of the Philippines.This dissertation contends that the Philippine Exposition was not a static imperial display but a dynamic site of negotiation in which Filipinos students, military Scouts, teachers, artisans, and performers improvised within, bent, and subverted the colonial framework. It is critical not to cast those at the fair solely as passive victims, despite the obviousness of their subjection, as doing so reproduces a colonial lens that erases their strategic, creative, and often courageous participation. Participants and performers carved out space for themselves in a number of improvisational ways: cultivating friendships across ethnolinguistic lines, building informal economies, shaping how they were photographed and described, and selectively embracing or resisting American expectations. Drawing on government records, press coverage, photographs, contracts, and personal accounts, this study examines how Filipino participants navigated surveillance and control by figures such as the Jefferson Guard and the Board of Lady Managers. It also explores how gender, ethnolinguistic identity, and class shaped these negotiations.Each chapter traces a different facet of Philippine presence at the Fair. Chapter One examines policing, racial order, and the Jefferson Guard’s role in shaping Filipino movement and visibility. Chapter Two looks at how the Board of Lady Managers embodied a model of elite white womanhood and motherhood that Philippine women were implicitly measured against, despite the Board’s limited formal power; their presence, along with the operation of the Model Playground, reinforced colonial expectations by framing white maternal care and moral supervision as the standard for proper conduct and child-rearing within the Philippine Reservation. Chapter Three explores how the Model School showcased education as a form of performative labor, with Filipino students and teachers, most visibly Pilar Zamora, serving as living demonstrations of colonial pedagogy. Zamora’s poised public role exemplified how select individuals navigated and sometimes leveraged the display of academic achievement to assert status within the constraints of U.S. imperial expectations. Chapter Four continues to inspect adult labor and commercial spectacle, highlighting how contracts, ethnological display, and affective work extracted value from Filipino bodies and skills. Chapter Five serves as a conclusion, and examines response to the Fair from elites in Manila, and touches upon the material afterlives of Philippine exhibits, tracing the dispersal, loss, and reinterpretation of objects and photographs and where future scholarship on the Exposition can move in the future.By reframing the 1904 Philippine Exposition as a contested arena rather than a one-way transmission of imperial ideology, this dissertation illuminates the complex, tactical ways Filipinos lived, worked, and negotiated under empire, and argues for future scholarship that centers their creativity and decision-making while resisting narratives that flatten them into either colonial subjects or passive victims. 
Alarm Calling to an Aerial Predator: Ecological and Evolutionary Drivers in a Neotropical Bird Community
No full textPredation risk exerts strong selective pressure on animals, and many species have evolved alarm calls to warn about threats in the environment. While avian alarm calling is well known in mixed-species flocks, few studies have directly tested how variation in intrinsic and extrinsic factors drives alarm behavior. We quantified several extrinsic ecological parameters and intrinsic factors such as degree of sociality, body size, and foraging strategy while controlling for phylogenetic signal. We exposed 69 species that vary in these qualities to a model predator (hawk fly-by) in the Peruvian Amazon. We found a clear positive relationship between social complexity and alarm calling—solitary birds alarmed least frequently, while mixed-species flocks alarmed most. Contrary to expectations, the ecological context (e.g., vegetation density and bird height) in the immediate environment had little influence on alarm behavior. Instead, phylogenetic linear mixed models revealed a strong phylogenetic signal in alarm calling propensity at the clade level. We also assessed the roles of species-specific foraging maneuvers and foraging substrates and their relative influence on alarm calling. The tendency to produce alarm calls appears to be rooted in evolutionary history, shaped by species-specific ecological traits and ancestral relationships more than by moment-to-moment environmental variation. Our findings provide new insight into the evolutionary and ecological drivers of anti-predator communication in avian communities
Sexual and Gender Diversity Beyond Minority Identities: Do Empirical Trends Call for a Paradigm Shift?
Get PDFIn the United States and many other societies, the 21st century has been characterized by an expansion of cultural and scientific conceptions of sexuality and gender to include such experiences as nonbinary gender, asexuality, sexual and gender fluidity, and forms of intimate diversity such as consensual nonmonogamies and kink. These expansive understandings provide the opportunity to reconsider the dominant paradigm in psychology that has historically positioned forms of sexual and gender diversity as indicative of minority identities. This article reviews four empirical trends that support this reconsideration: (1) the proliferation of new language to describe gender and sexuality; (2) the rising identification with any form of sexual and gender diversity, especially among people born this century; (3) growing evidence of sexuality as flexible and fluid across the life course; and (4) rising visibility of forms of intimate diversity such as consensual nonmonogamies and kink. A psychology of sexuality and gender that centers phenomena associated with sexual and gender diversity, rather than different types of people in an ever-exclusionary minoritized acronym such as “LGBTQ,” might prove more relevant to the current century and more sensitive to historical and cultural variability. Empirical practices within such a paradigm would (1) prioritize social documentation using both qualitative and quantitative methods, (2) be mindful of response categories in interview and survey research, (3) avoid aggregation across identities, and (4) acknowledge cultural variability in sexuality and gender
Jobs-Housing Balance and Fit
Get PDFThis project reviews and summarizes empirical evidence for a selection of transportation and land use policies, infrastructure investments, demand management programs, and pricing policies for reducing vehicle miles traveled (VMT) and greenhouse gas (GHG) emissions. The project explicitly considers social equity (fairness that accounts for differences in opportunity) and justice (equity of social systems) for the strategies and their outcomes. Each brief identifies the best available evidence in the peer-reviewed academic literature and has detailed discussions of study selection and methodological issues. VMT and GHG emissions reduction is shown by effect size, defined as the amount of change in VMT (or other measures of travel behavior) per unit of the strategy, e.g., a unit increase in density. Effect sizes can be used to predict the outcome of a proposed policy or strategy. They can be in absolute terms (e.g., VMT reduced), but are more commonly in relative terms (e.g., percent VMT reduced). Relative effect sizes are often reported as the percent change in the outcome divided by the percent change in the strategy, also called an elasticity
ZTF SN Ia DR2: Impact of the galaxy cluster environment on the stretch distribution of Type Ia supernovae
No full textContext. Understanding the impact of the astrophysical environment on Type Ia supernova (SN Ia) properties is crucial to minimize systematic uncertainties in cosmological analyses based on this probe. Aims. We investigate the dependence of the SN Ia SALT2.4 light-curve stretch on the distance from their nearest galaxy cluster to study the potential effect of the intracluster medium (ICM) environment on the intrinsic properties of SN Ia. Methods. We used the largest SN Ia sample to date and cross-matched it with existing X-ray, Sunyæv-Zel'dovich, and optical cluster catalogs in order to study the relation between the stretch and the distance to the nearest detected cluster from each SN Ia. We modeled the underlying stretch distribution with a Gaussian mixture with relative amplitudes that depended on redshift and clustercentric distance. Results. We find that the fit quality of the stretch distribution improves significantly when we included the distance-dependant term in the model with a variation of the Akaike information criterion ΔAIC = -10.2. Because of the known correlation between galaxy age and distance from the cluster center, this supports previous evidence that the age of the stellar population is the underlying driver of the bimodal shape of the SN Ia stretch distribution. We further computed the evolution of the fraction of quenched galaxies as a function of distance with respect to cluster center from our best-fit model of the SNe Ia stretch distribution and compared it to previous results obtained from Hα line measurements, optical broadband photometry, and simulations. We find our estimate to be compatible with these results. Conclusions. The results of this work indicate that SNe Ia searches at high redshift targeted toward clusters to maximize detection probability should be considered with caution as the stretch distribution of the detected sample would be strongly biased toward the old subpopulation of SNe Ia. Furthermore, the effect of the ICM environment on the SN Ia properties appears to be significant from the center of the clusters up to their splashback radius. This is compatible with previous works based on observations and simulations of a galaxy age gradient with respect to clustercentric distance in massive cluster halos. The next generation of large-area surveys will provide an increase of an order of magnitude in the size of SN Ia and cluster catalogs. This will enable us to analyze the impact of cluster mass on the intrinsic properties of SNe Ia and of the fraction of quenched galaxies in the outskirts of clusters in more detail, where direct measurements are challenging
ZTF SN Ia DR2: Overview
No full textWe present the first homogeneous release of several thousand spectroscopically classified type Ia supernovae (SNe Ia) with spectroscopic redshifts. This release, named "DR2", contains 3628 nearby (z < 0.3) SNe Ia discovered, followed, and classified by the Zwicky Transient Facility survey between March 2018 and December 2020. Of these, 3000 have good-to-excellent sampling and 2667 pass standard cosmology light curve quality cuts. This release is thus the largest SN Ia release to date, increasing by an order of magnitude the number of well-characterized low-redshift objects. With DR2, we also provide a volume-limited (z < 0.06) sample of nearly a thousand SNe Ia. With such a large, homogeneous, and well-controlled dataset, we are studying key current questions on SN cosmology, such as the linearity SNe Ia standardization, the SN and host dependencies, the diversity of the SN Ia population, and the accuracy of current light curve modeling. These, and more, are studied in detail in a series of articles associated with this release. Alongside the SN Ia parameters, we publish our forced-photometry gri-band light curves, 5138 spectra, local and global host properties, observing logs, and a Python tool to facilitate the use and access of these data. The photometric accuracy of DR2 is not yet suited for cosmological parameter inference, which will follow as the "DR2.5" release. We nonetheless demonstrate that our Hubble diagram of several thousands of SNe Ia has a typical 0.15 mag scatter