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Penn Library\u27s Ms. Codex 1674 - [Sefer Raziel HaMalach... etc.]. (Video Orientation)
No full texthttps://repository.upenn.edu/sims_video/1156/thumbnail.jp
Collation Model for Oversize Ms. Codex 1225: Ex lib[ris] Paris de Grassis Bonon[iensis]
Get PDFAn abridged summary of the continuation of Burchard\u27s Diarium by Paris de Grassis, master of ceremonies under popes Julius II and Leo X, covering the pontificate of Leo X up to 1521, followed by a further continuation by Blasius Martinellus up to 1538 (and thus encompassing Adrian VI, Clement VII, and part of Paul III). By far the largest section is devoted to 1513, the year of Leo\u27s accession, with the amount given to each year declining sharply thereafter until 1538 receives only half of a page. Written in Italy.https://repository.upenn.edu/sims_models/1100/thumbnail.jp
Implicit Bias and Pit Bull Welfare
Get PDFBreed Specific Legislation exists in 719 localities across the United States, the majority of places target Pit Bulls, either in conjunction with other breeds or solely. The negative view of Pit Bulls is based on a multitude of factors, one of which could be the perception of the likely owner of this breed. Pit Bulls are frequently associated with inner-city persons of color, although this has not always been the case. Other breeds have been identified in the past as being the most dangerous breed; however, Breed Specific Legislation started with the change in perception of the Pit Bull. This paper examines the correlation between areas which implemented Breed Specific Legislation and the racial demographics of the community
(Commercial) Automatic Speech Recognition as a Tool in Sociolinguistic Research
Get PDFAs speech datasets used in sociolinguistic research increase in size, laborious and time-intensive manual orthographic transcription is a challenge, limiting the amount of (transcribed) data which can be analysed. In this paper, I discuss the use of (commercial) automatic speech recognition (ASR) as a tool in sociolinguistic research in the context of a case study: the Lothian Diary Project. I describe the kinds of errors produced by two commercial ASR systems for British English within the broader context of algorithmic bias in ASR, and suggest some best practices when working with ASR in sociolinguistic work
Essays On Corporate Governance And Shareholder Activism
Get PDFThe goal of this dissertation is to deepen our understanding of corporate governance and shareholder activism.
The first chapter, The Roles of Activists in Boardrooms: Advisors and Supervisors , studies the effects of activist directors on firm outcomes. Using a unique hand-collected data set of activist directors\u27 committee appointments, I show that their impacts depend on whether they sit on advisory or monitoring committees. Shareholders benefit from the appointments of activist directors: the average abnormal return increases by 1.9% and 1.4% around the day of advisory and monitoring directors\u27 appointments, respectively. By using close-call director election results in a regression discontinuity design, I provide causal evidence that activist hedge funds perform two distinct governance roles of advising and monitoring, with each role producing different outcomes. Upon being appointed to advisory committees, activist directors increase operating performance by enhancing profitability and internal capital allocation. They also increase corporate innovation, acquisitions, and divestitures to drive long-term growth. Upon their appointments to monitoring committees, activist directors curb agency problems by increasing shareholder payouts, divestitures, CEO turnover, and pay-performance sensitivity while decreasing acquisitions. My findings shed light on the roles of activists as advisors and supervisors. The second chapter, The Aftermath of Settlements: Hedge Fund Activism and Corporate Risk-Taking , studies the effects of activist settlements on corporate risk-taking using board settlements and hand-collected golden leash agreements data. I find causal evidence against the claim that board settlements tilt the direction of management toward short-termism, leading to excessive risk-taking. I identify two mechanisms that explain the decrease in corporate risk-taking: increased board monitoring and change in ownership structure. Taken together, my findings show that activists decrease corporate risk-taking, causing improvements in long-term firm value
Creating Dynamical Robots Of Different Morphologies And Sizes Through Automatic Origami Design
No full textOrigami robots are machines whose morphologies and functions are created by folding locally flat sheets. This thesis makes three contributions to the design and fabrication of origami robots aimed at the development of an automated computational pipeline for the specification and construction of widely different morphologies and body sizes capable of highly dynamic operation. The initial contribution recruits recent advances in the design of compliant folded structures to build the first soft robots that exhibit highly dynamic behavior. Specifically, the proof-of-concept robots reported here achieve their juggling and hopping behaviors by actuating their origami springs as power-cascading devices. Second, this thesis advances the origami design literature by automating the construction of compliant origami kinematic chains. The “Kinegami” algorithm reported here accepts a Denavit-Hartenberg kinematic specification and uses a catalog of tunably compliant origami modules to generate a crease pattern that folds into the prescribed serial robot mechanism. Finally, the thesis addresses the problem of scalability in general (not just origami) robot design by studying the simultaneous interaction of structural integrity and actuator affordance. Four contrasting abstract task domains impose different scaling criteria that reveal the relative advantages and disadvantages of three distinct structural principles combined with three different actuator types. For example, applying the unloaded dynamic task criterion to a direct drive actuation type reveals that the origami-style shell structure supports superior length scale-up. An accompanying empirical study confirms that structural alternatives cannot achieve a one-degree-of-freedom hopping task at the same five-fold scale-up of the original hopper design exhibited by the shell structure design.
Considered in isolation, these contributions advance, respectively, the recent soft robotics literature, the older origami design literature, and the traditional engineering scaling literature. Considered together, they advance the agenda for the rapid, computer-assisted design of customized, high-performance robots
Polymer Dynamics In Disordered Nanoparticle Packings: Effect Of Confinement, Interfaces, And Humidity
Get PDFInfiltration of polymers into disordered nanoparticle packings has shown to be a powerful method of fabricating highly loaded nanocomposites with superb mechanical properties. Polymer-infiltrated nanoparticle packings provide a unique platform to study the dynamics of macromolecules under extreme nanoconfinement. The degree of confinement can be tuned by appropriate choice of particle size and polymer molecular weight. The presence of large interfacial area between the polymer and the particle, high degree of nanoconfinement, and environmental triggers like atmospheric humidity can impact the dynamics of polymers at the segmental and the chain level. By using tools like microscopy, ellipsometry and molecular dynamic simulations, we investigate the dynamics of polymers at unprecedented levels of confinement. In solvent-driven infiltration of polymers (SIP) system, polymer chains are plasticized by capillary condensed solvent leading to capillary motion of the solvated polymer into the pores of the nanoparticle packing. We detail our investigations on the mechanism of infiltration with increasing polymer-nanoparticle interactions. In capillary rise infiltration(CaRI), the polymer film-nanoparticle packing bilayer is annealed above the glass transition temperature of the polymer leading to the polymer wicking into the pores of the packing. The dynamics of rise of the polymer into the nanoparticle packing can be studied by ellipsometric front-tracking giving a measure of the chain dynamics of polymer – effective viscosity – based on the Lucas-Washburn equation. Our investigations into the dynamics of high Tg, glassy polymers is complemented by studies of low Tg, mobile chains in disordered nanoparticle packings. Once infiltrated into a region of nanoparticle packings, these mobile chains spread out into adjoining unfilled regions. This room temperature, spontaneous lateral motion of polymer can be tracked to understand interfacial polymer diffusion under confinement. Higher humidity, unexpectedly, leads to faster spreading of the polymers within the packings possibly due to reduced particle-polymer friction with water coverage on particle surface. Thus, this work presents the effects of confinement, interfacial interactions, and atmospheric humidity on the chain and segmental dynamics of polymers in pores of disordered nanoparticle packings
Localizing Seizure Onset With Diffusion Models
Get PDFDiffusion models are models that describe the spread of anything -- atoms, ideas, people, seizures. They have developed independently across fields, from economics, computer science, and physics, to biology and medicine. They have a wide variety of applications including modeling the spread of pathogens, information, and ideas. In this dissertation, diffusion models are applied to modeling the spread of seizures. Our ability to predict how seizures spread -- its timing, speed, extent of activity, where seizures start and where seizures go -- can help us solve a critical problem in the effective treatment of refractory epilepsy: localization of seizure onset for its eventual resection, ablation, or neuromodulation. This dissertation encompasses a multidisciplinary approach (from analyses of signals and networks to newer methods in deep learning) across many brain states (from interictal, preictal, ictal to postictal) and with multimodal data (from structure to function, MRI to EEG) in different outcomes of epilepsy patients (from good to poor). New hypotheses about epilepsy pathophysiology are presented in the original research section of this dissertation, a new framework on the conceptualization of brain atlas is presented in Chapter 5, a taxonomy of seizure spread patterns is presented in Chapter 6, the investigation of white matter EEG recordings is presented in Chapter 7 -- this dissertation contains work more than about diffusion models applied to epilepsy; however the research and ideas presented throughout this work show promise for using diffusion models, or other models of epilepsy, to solve a clinical problem in epilepsy and hopefully improve our patients\u27 quality of life
Covenantal Connections: Visualizing Mosaic Law In The Middle Ages
Get PDFABSTRACT
COVENANTAL CONNECTIONS: VISUALIZING MOSAIC LAW IN THE MIDDLE AGES
Abigail S. Rapoport
Dr. Sarah M. Guérin
This dissertation examines iconography related to the Mosaic covenant in Jewish and Christian contexts of western Europe, specifically the regions of northern France and the Holy Roman Empire from circa 1150 to 1348. While there is more than one covenant in the Hebrew Bible, this project discusses the Mosaic covenant—ratified by the Tablets of Law delivered to Moses and the Israelites at Mount Sinai—which holds essential concern for both Jewish and Christian communities of the later Middle Ages. By situating the imagery of the Mosaic covenant within internal developments pertinent to both communities, this study illuminates how such covenantal iconography was intricately tied to current concerns, shaped by matters of the day, and key to fashioning their respective identities.
Building on and departing from past literature, this study focuses on how Jewish communities in medieval Ashkenaz perceived themselves in relation to the Mosaic covenant vis-à-vis their own internal communal developments, in dialogue with liturgical practices. This study is the first to examine a corpus of six festival prayerbooks (mahzorim) from medieval Ashkenaz, particularly the imagery and liturgy for Shavuot (“Festival of Weeks”), the holiday that commemorates the biblical event of Moses and the Israelites receiving the Ten Commandments on the Tablets of Law at Mount Sinai. Mahzorim, used by the Jewish communities in liturgical practice, furnish valuable evidence for reconstructing a living tradition when almost all other evidence has been lost. This dissertation investigates the different visual strategies deployed for illustrating the scene of the revelation of the Law and argues that the mahzorim, contextualized within the pertinent liturgy and ritual practices, aided the Jewish communities of medieval Ashkenaz in asserting their ongoing covenantal connections within their contemporary Jewish practice
Synthesis And Reactivity Of Flexible Dicopper Bis(pyridyldiimine) Macrocyclic Complexes
Get PDFMethanol is a viable fuel source and a common feedstock in the chemical industry. Currently, much of the methanol produced by industry is derived from natural gas (methane). Yet, the one-step selective oxidation of methane to methanol remains challenging due to the potential formation of overoxidation products (CO2, H2O, etc.). Within the past 20 years, the reactive Cu2(II,II)-µ-O site within Cu(II)-ZSM-5 has been shown capable of the selective oxidation of methane to methanol through a hydrogen atom transfer (HAT)/radical rebound mechanism. The proximity of the metals and geometric constraints may allow for the copper centers to work in concert when facilitating HAT. To probe how metal-metal distance and coordination geometry influence C–H bond oxidation, it is highly desirable to study the properties and reactivity profile of discrete multinuclear model complexes. Here, we report a new protocol for the synthesis of homobimetallic copper(II) complexes using various derivatives of a macrocycle containing two pyridyldiimine units. A series of Cu2-(µ-X)n bis(4-tert-butylpyridyldiimine) macrocyclic complexes (n = 1, 2; X = Cl, Br, N3, NO2, OTMS, OH) were synthesized and crystallographically characterized. The development of new macrocyclic ligands was also undertaken to provide a modular synthesis of bis(pyridyldiimine) ligand scaffolds, in which the steric and electronic profiles can be easily tuned. Using the newly established synthetic protocols and macrocyclic ligands, two Cu2(II,II)-µ-OH complexes were prepared and analyzed by cyclic voltammetry and low-temperature 1H NMR spectroscopy. The macrocyclic complexes differed in the aliphatic linkers between the pyridyldiimine units (ethylene vs. propylene linker). New Cu2(II,II)-µ-O complexes were accessed through deprotonation of the hydroxide starting materials. The µ-oxo complexes were found competent for hydrogen atom transfer reactions, showing reactivity towards weak C-H and N-H bonds. From these studies, the size of the macrocycle was found to influence the reactivity of the µ-oxo complexes. The HAT reactions afforded Cu2(I,II)-µ-OH complexes, and O-H BDFEs of 74.3 ± 1.4 (propylene-linked complex) and 79.0 ± 1.5 kcal/mol (ethylene-linked complex) were estimated using Bordwell’s thermodynamic square scheme approach