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St. Martinville Louisiana Baptism Network
No full textThis dataset includes a transcription of the baptismal register for the French Catholic church Saint-Martin des Attakapas, now modern St. Martinville Louisiana, as well as a cleaned version of each baptism formatted as source-target pairs for social network analysis. The data includes 163 baptisms from 1756 to 1794, mainly of displaced Acadians. A handful of enslaved and Indigenous people are also represented. The data has been prepared for network analysis by regularizing the spelling of names. Source/Target pairs for network analysis were created by creating a pair between all adults who participated in a baptism. The network is assumed to be undirected. The year of baptism or edge creation is included in the edgelist file
Understanding Street Tree Species Composition Shifts Over Time
Get PDFUrban forests are among the most dynamic and essential ecosystems in the age of the Anthropocene, where land use is ever evolving to serve human needs. Cities have adopted strategies such as increasing canopy cover via tree planting initiatives to combat the negative impacts of development. If properly distributed and maintained, these organisms promote a wide range of benefits, from cooler temperatures to happier residents. Achieving a healthy street tree community, for example, requires regular assessments and diligent management to understand forest characteristics and species-specific implications on the vigor of trees and the surrounding environment. While data for one planting season or a static inventory provides a snapshot in time of urban forest structure, often addressing acute or temporary solutions for areas of concern, analyzing trends in planting records over time can shed light upon management decisions of the past, present, and future. In this study, I show that street tree planting initiatives in Philadelphia, PA have shifted focus from larger, non-native species to a variety of medium- and small-stature species. Using street tree planting records from both a public agency and a non-profit program, I identified a transition from planting almost exclusively large species, as high as 99.17% of plantings in the 1950s, to a more diverse and evenly distributed community of small-, medium-, and large-stature trees in the 2000s, with relative planting abundances of 21.77%, 44.14%, and 31.43%, respectively. Further, I found that native plantings increased by as much as +95.74% in later years. Quantifying the species composition paradigm of street tree systems can provide insights as to how and why these susceptible communities are changing, and how these changes may affect ecosystem service potential
Exploring with Sticky Mittens: Reinforcement Learning with Expert Interventions via Option Templates
Get PDFLong horizon robot learning tasks with sparse rewards pose a significant challenge for current reinforcement learning algorithms. A key feature enabling humans to learn challenging control tasks is that they often receive expert intervention that enables them to understand the high-level structure of the task before mastering low-level control actions. We propose a framework for leveraging expert intervention to solve long-horizon reinforcement learning tasks. We consider option templates, which are specifications encoding a potential option that can be trained using reinforcement learning. We formulate expert intervention as allowing the agent to execute option templates before learning an implementation. This enables them to use an option, before committing costly resources to learning it. We evaluate our approach on three challenging reinforcement learning problems, showing that it outperforms state-of-the-art approaches by two orders of magnitude
Criticality in Eternal Inflation and Superfluidity
No full textThis thesis focuses primarily on false-vacuum eternal inflation on the string landscape. Its main goal is to shed light on a dynamical phase transition discovered recently, which occurs when de Sitter vacua in a region of the landscape have an average lifetime of order the de Sitter Page time. We first aim to understand the mechanism driving the inflationary multiverse to the critical point. For this purpose, we focus on a finite region of the landscape, which exchanges volume with surrounding vacua, and as such acts as an open system. The surrounding vacua, which play the role of an environment, result in a driving term for vacua in the region, with uncorrelated, white noise fluctuations. We show that the static susceptibility of the region diverges as the average lifetime of de Sitter vacua approaches the Page lifetime. Thus optimal regions of the landscape are most susceptible to volume influx from their environing landscape. We then show that the rescaled comoving volume fluctuations exhibit a 1/f power spectrum over a broad range of frequencies, precisely at the critical Page lifetime distribution. A 1/f power spectrum is a hallmark of non-equilibrium systems at criticality. In analogy with sand avalanches in the abelian sandpile or neuronal avalanches in the brain, de Sitter vacua at criticality can be thought of as undergoing scale invariant volume fluctuation avalanches. We then study the critical properties of the inflationary multiverse from the information-theoretic perspective. We show that the string landscape has emergent computational capabilities at the critical Page distribution. Specifically, we find that integrated information storage is enhanced when the average lifetime of the vacua is of the order of the Page time. Other indications of criticality, such as optimization between the integrated storage and information storage rates or competition between information storage and transfer, are also discussed. At last, we study the separate topic of the Bose-Einstein condensation and superfluidity at non-zero temperature. We derive the equation of state of a Bose gas accounting for thermal and quantum corrections up to 1-loop order. We work in the Hartree-Fock-Bogoliubov approximation and follow Yukalov\u27s prescription of introducing two chemical potentials, one for the condensed phase and another one for the excited phase, to circumvent the well-known Hohenberg-Martin dilemma. Finally, we connect our results to the hydrodynamical, two-fluid model for finite-temperature superfluids. Our results are relevant for the phenomenology of Bose-Einstein condensate and superfluid dark matter candidates, as well as the color-flavor locking phase of quark matter in neutron stars
A Spin-Lattice Dynamics Model with Improved Energy and Angular Momentum Conservation
No full textMagnetic materials are critically important in a wide range of application areas including data storage, medicine, energy harvesting, and refrigeration. Atomistic numerical simulations of magnetic materials can provide important insight in these applications because they offer the ability to track phenomena such as magnon-phonon interactions, ultrafast demagnetization processes, and magnetization and energy at time and length scales that can be difficult to observe experimentally. Spin-lattice dynamics, a classical atomistic simulation method that models atomic magnetic moments and atomic displacements simultaneously, is able to capture these phenomena. Unfortunately, energy stability can be a challenge in spin-lattice dynamics simulations and angular momentum artifacts are a known issue in atomistic models of periodic systems. Both of these problems can cause errors in the evolution of spin orientations and atomic positions, leading to unphysical predictions of temperature, magnetization, and thermal-magnetic coupling in magnetic materials. This dissertation presents an improved computational model for spin-lattice dynamics simulations developed to address the above challenges. The model offers superior energy and magnetization conservation and the ability to quantify lattice angular momentum changes generated by spin relaxation processes in bulk materials. The improvements made in this work advance spin-lattice dynamics as a computational tool for the design and analysis of magnetic materials
Unmasking the Role of the Ubiquitin Ligase FBXW7 Beta Isoform in B-Lymphopoiesis and Leukemia
No full textNon-canonical exon usage plays many important roles in cellular phenotypes, but its contribution to human B-cell development remains sketchily understood. To fill this gap, we collected various B-cell fractions from bone marrow and tonsil donors, performed RNA-seq, and examined transcript variants. We identified 150 genes that harbor local splicing variations in all pairwise comparisons. One of them encodes FBXW7, an E3 ubiquitin ligase implicated as a cancer driver in several blood cancers. Surprisingly, we discovered that in normal human pro-B cells, the predominant transcript utilized an alternative first exon to produce the poorly characterized FBXW7β isoform, previously thought to be restricted to neural tissues. The FBXW7β transcript was also abundant in cell lines and primary samples of pediatric B-cell acute lymphoblastic leukemia (B-ALL), which originates in the bone marrow. When overexpressed in a heterologous cell system, this transcript yielded the expected protein product, as judged by anti-FLAG immunoblotting and mass spectrometry. Furthermore, in REH B-ALL cells, FBXW7β mRNA was the only FBXW7 isoform enriched in the polyribosome fraction. To shed light on possible functions of FBXW7β, we utilized gain- and loss-of-function approaches and identified an FBXW7β-dependent inflammatory gene signature, apparent in a subset of B-ALL with high FBXW7β expression. This signature contained several members of the TNF superfamily, including those comprising the HLA Class III cluster (LTB, LST1, NCR3, LTA, and NFKBIL1). Our findings suggest that FBXW7β expression drives proinflammatory responses, which could contribute to normal B-cell development, leukemogenesis and responses to anti-cancer therapies
Burned Flint: Indirect Evidence of Fire Use for Understanding Neandertals’ Behavioral Variability in Using Fire in Late Pleistocene Europe
No full textPyrotechnology is an ancient technology. Similar to stone tool technology, the role of fire in the lives of early hominins has changed over time—from the opportunistic acquisition of fire through natural causes such as lightning strikes to the habitual production and use of pyrotechnology for warmth and subsistence. One difference between stone tool technology and pyrotechnology, however, is that the emergence of new lithic technology evolved roughly chronologically. While there is abundant evidence of fire use during the Mesolithic and Neolithic, our understanding of pyrotechnology in the Paleolithic is not straightforward because environmental variables, such as climate and geography, have significantly affected fire use across different archaeological contexts. Analyzing burned flint as one indirect evidence of fire use in this dissertation, I examined how environmental variables, such as geography (e.g., latitude and altitude) and climatic regimes (cold vs. temperate) influenced the use of fire by Neandertals and modern humans. Additionally, analyzing burned flints from a wide range of late Pleistocene archaeological sites, I addressed some of the questions regarding post-depositional impacts on burned flints. First, through conducting a pilot freeze-thaw experiment using knapped flint flakes, I justified criteria used to identify burned flints in this dissertation. Second, I conducted a pilot heat experiment to examine a) under what heating conditions one of the most visible thermal characteristics of burned flint, potlids, are formed on flake surfaces, and also to b) examine the breakage pattern of burned flakes. Furthermore, to strengthen the count method of burned flint, I applied an aggregate weight method to archaeological flints, which is applicable to any lithic assemblage with size distribution variability and thermal breakage. Finally, the analysis of archaeological lithic collections and pilot experimental studies indicate that burned flints provide more reliable evidence for fire use, with which we were able to measure one of the early hominins’ adaptive behaviors (i.e., fire use) regarding the location they occupied and climatic conditions that they experienced
¡están en nosotros! el horror de la marginalidad y las fantasías de la clase media en un estudio de cine y literatura en Argentina, México y El Salvador durante la época neoliberal
No full textThe present dissertation analyses several works of film and literature from the last quarter of a century in order to explore the influence of neoliberalism in Latin America, with a focus on Argentina, Mexico and El Salvador. The hypothesis is that the changes promoted by this program have been so deep, that have become an inescapable topic within these texts. Furthermore, this dissertation examines the constant presence of the marginal masses in these works, and their immediate relationship with the reconfiguration of neoliberal society. Through a close reading of the texts under a cultural studies optic, this research confirms the richness of fantasy, violence and science fiction for an analysis of the Latin American middle class’ ideology. Moreover, the masses appear as an integral part of such ideology and its psychological consequences. We can then observe two main tendencies regarding the vision of said masses: one as a polluting element that risks corrupting the lives of the middle class (Argentina), and one that identifies them with the sunk or the loser, as those who were unable to adapt to the new times and whose death has been naturalized (Mexico, El Salvador)
Loss of AID Exacerbates the Malignant Progression of CLL
No full textActivation-induced cytidine deaminase (AID) has been implicated as both a positive and a negative factor in the progression of B cell chronic lymphocytic leukemia (CLL), but the role that it plays in the development and progression of this disease is still unclear. We generated an AID knockout CLL mouse model, AID-/-/Eμ-TCL1, and found that these mice die significantly earlier than their AID-proficient counterparts. AID-deficient CLL cells exhibit a higher ER stress response compared to Eμ-TCL1 controls, particularly through activation of the IRE1/XBP1s pathway. The increased production of secretory IgM in AID-deficient CLL cells contributes to their elevated expression levels of XBP1s, while secretory IgM-deficient CLL cells express less XBP1s. This increase in XBP1s in turn leads AID-deficient CLL cells to exhibit higher levels of B cell receptor signaling, supporting leukemic growth and survival. Further, AID-/-/Eμ-TCL1 CLL cells downregulate the tumor suppressive SMAD1/S1PR2 pathway and have altered homing to non-lymphoid organs. Notably, CLL cells from patients with IgHV-unmutated disease express higher levels of XBP1s mRNA compared to those from patients with IgHV-mutated CLL. Our studies thus reveal novel mechanisms by which the loss of AID leads to worsened CLL and may explain why IgHV-unmutated CLL is more aggressive than IgHV-mutated CLL
Paving the Way to Empire: Roads in Ethiopia from Menelik II to Mussolini
No full textThis dissertation traces the history of road construction in Ethiopia from the 1850s to 1950s, examining how roads became a central symbol of modern imperial power and altered the ways ordinary people came into contact with the state, and with each other. Most accounts of road construction in Ethiopia start with the Italian occupation from 1936 to 1941, which saw Mussolini realize, at considerable cost to Italy, an expansive network of roads to connect the territories of his new East African empire, Africa Orientale Italiana. While the central chapters of this dissertation, indeed, focus on road projects launched during the five years of Italian Fascist rule, they seek to add to the scholarship in a number of important ways. To begin with, the scale of the “Mussolinian” enterprise has tended to overshadow the fact that Ethiopian emperors had already started to use roads to consolidate and centralize their power decades earlier. Highlighting the continuities between the Ethiopian imperial vision and the later Italian one allows us to re-periodize the story of roads in the making of the modern Ethiopian state, and suggests that there is methodological value in examining the history of an infrastructure over the longue durée. Then, by carefully reading between the lines of a combination of “official” and less conventional Italian sources, including the records of the Italian military tribunals for East Africa and the photography archives of the Istituto agronomico per l’Africa Italiana and the Touring Club Italiano, I show how road construction during the Italian occupation altered the spaces and experiences of daily life for Ethiopians, and how Ethiopian realities, in turn, thwarted and complicated Italian ambitions. As a technology that transformed mobility and expanded the reach of the state, roads created new obligations and opportunities for the communities they traversed. In reconstructing how people perceived and capitalized on this connectivity, this dissertation also speaks to the histories of labor, imperial governance, and urbanization in modern Ethiopia