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Selective skeletal editing of polycyclic arenes using organophotoredox dearomative functionalization
No full textReactions that lead to destruction of aromatic ring systems often require harsh conditions and, thus, take place with poor selectivities. Selective partial dearomatization of fused arenes is even more challenging but can be a strategic approach to creating versatile, complex polycyclic frameworks. Herein we describe a general organophotoredox approach for the chemo- and regioselective dearomatization of structurally diverse polycyclic aromatics, including quinolines, isoquinolines, quinoxalines, naphthalenes, anthracenes and phenanthrenes. The success of the method for chemoselective oxidative rupture of aromatic moieties relies on precise manipulation of the electronic nature of the fused polycyclic arenes. Mechanistic studies show that the addition of a hydrogen atom transfer (HAT) agent helps favor the dearomatization pathway over the more thermodynamically downhill aromatization pathway. We show that this strategy can be applied to rapid synthesis of biologically valued targets and late-stage skeletal remodeling en route to complex structures
Stereocontrolled 1,3-nitrogen migration to access chiral alpha-amino acids
No full textalpha-Amino acids are essential for life as building blocks of proteins and components of diverse natural molecules. In both industry and academia, the incorporation of unnatural amino acids is often desirable for modulating chemical, physical and pharmaceutical properties. Here we report a protocol for the economical and practical synthesis of optically active alpha-amino acids based on an unprecedented stereocontrolled 1,3-nitrogen shift. Our method employs abundant and easily accessible carboxylic acids as starting materials, which are first connected to a nitrogenation reagent, followed by a highly regio- and enantioselective ruthenium- or iron-catalysed C(sp(3))-H amination. This straightforward method displays a very broad scope, providing rapid access to optically active a-amino acids with aryl, allyl, propargyl and alkyl side chains, and also permits stereocontrolled late-stage amination of carboxylic-acid-containing drugs and natural products
The Practice and Purpose of Adaptation of Classical Texts
Get PDFThis paper focuses on two adaptations of classical texts: Off the Rails, Reinholz’s adaptation of Shakespeare’s Measure for Measure, and AtGN, Howard’s adaptation of Sophocles’ Antigone, and examines the ways in which these plays both replicate the cycles created by the original texts and seek to break from them. Taking theater as an inherently repetitive practice, this paper pulls from many sources to develop a vocabulary for discussing theatrical adaptations, then applies it to these two case studies to demonstrate that each uses a variety of strategies to create a new narrative. Whether a theater-maker is building new meaning into the core tenets of the story or picking up the baton and running with it, adaptation creates a potential space, within which playwrights and other theater artists have the opportunity to work with or against the original text, interrogate and remake the story, pull lines of connection between histories and cultures, and add new voices to the conversation
Racial Domination Through the Grey Areas: The Categorization of Mixed-Race in the United States and Brazil
Get PDFA historical comparison of mixed-race categories in the United States and Brazil, analyzing the influence of governments and political groups
\u27Pure or Tainted?\u27: Representing a Source of Colonial Bengali-English Music in RISM
No full textEnglish: In 2019, the U.S. RISM Office created a catalogue record for a notated manuscript of the opera Satī ki kalaṅkinī (সতী কি কলঙ্কিনী, \u27Pure or Tainted?\u27) by Nāgendranath Bandyopādhyāẏ and Modan Mohan Barmaṇa. Written in Calcutta in 1876 and presently housed at Harvard Library, the opera offers passages in Bengali and English script accompanied by music notation in a parallel format. The office chose to pursue Satī ki kalaṅkinī as a test case for exploring opportunities to draw non-European music into a project such as RISM but faced ambivalence about speaking on behalf of its \u27Indian\u27 pasts. This study engages particularly with the ethics of transcription and visibility, while also drawing attention to the text\u27s cultural setting. Recently, questions of representation have taken on exceptional significance in U.S. academic libraries, owing to a managerial turn toward diversity, equity, inclusion, and antiracism. We share this case as a contribution to a more robust and realistic understanding of global music cultures, including those from colonial encounters.
French:En 2019, le bureau américain du RISM a créé une notice de catalogue pour un manuscrit musical de l\u27opéra Satī ki kalaṅkinī (সতী কি কলঙ্কিনী, « Pur ou entaché? ») de Nāgendranath Bandyopādhyāẏ et Modan Mohan Barmaṇa. Écrit à Calcutta en 1876 et actuellement conservé à la bibliothèque de l\u27université de Harvard, l\u27opéra comprend des textes en bengali et en anglais accompagnés de notations musicales dans un format parallèle. On a choisi de poursuivre Satī ki kalaṇkinī en tant que test pour explorer les possibilités d\u27intégrer la musique non-européenne dans le RISM, tout en gardant à l\u27esprit le défi ambivalent de parler au nom d\u27un passé « indien ». L\u27article examine en particulier les questions éthiques liées à la transcription et au mode de présentation et tient également compte de la dimension culturelle de la source. Récemment, les questions de représentation en ce qui concerne la diversité, l\u27équité, l\u27inclusion et l\u27antiracisme ont pris une importance exceptionnelle dans les bibliothèques universitaires américaines. En ce sens, l\u27étude de cas se veut une contribution à une compréhension plus solide et plus réaliste des cultures musicales mondiales, y compris celles issues de contextes coloniaux.
German: 2019 erstellte die US-amerikanische Arbeitsstelle von RISM einen Katalogeintrag für eine Musikhandschrift der Oper Satī ki kalaṇkinī (সতী কি কলঙ্কিনী, Rein oder befleckt?\u27) von Nāgendranath Bandyopādhyāẏ und Modan Mohan Barmaṇa. Sie entstand 1876 in Kalkutta und wird jetzt in der Bibliothek der Harvard University verwahrt. Das Manuskript präsentiert den Textteil (in Bengalisch und Englisch) mit jeweils zugehöriger musikalischer Notation in synoptischer Darstellung. Man unternahm die Katalogisierung als Testfall, um daran Möglichkeiten zu erproben, wie nicht-europäische Musik in RISM integriert werden kann, sehr wohl eingedenk der ambivalenten Herausforderung, für eine ‚indische\u27 Vergangenheit zu sprechen. Der Beitrag befasst sich insbesondere mit den ethischen Fragen der Transkription und Darstellungsweise und berücksichtigt auch die kulturelle Dimension der Quelle. In letzter Zeit haben aufgrund der Sensibilisierung für Diversität, Gleichstellung, Inklusion und Antirassismus Fragen der adäquaten Repräsentation eine besondere Bedeutung in den wissenschaftlichen Bibliotheken der USA erlangt. Insofern versteht sich die Fallstudie als Beitrag zu einem solideren und realistischeren Verständnis globaler Musikkulturen, auch solchen aus kolonialen Kontexten
Or, (2022) Image 25
No full textOr,December 8-11, 2022Irene and Alan Wurtzel Theater, Oberlin College
By Liz Duffy AdamsDirected by Chris Flaharty
More information about this productionhttps://digitalcommons.oberlin.edu/images_or/1024/thumbnail.jp
The Amateurs (2022)
Get PDFhttps://digitalcommons.oberlin.edu/productions_2022-2023/1003/thumbnail.jp
The ALMaQUEST Survey X: what powers merger induced star formation?
No full textGalaxy mergers are known to trigger both extended and central star formation. However, what remains to be understood is whether this triggered star formation is facilitated by enhanced star formation efficiencies (SFEs), or an abundance of molecular gas fuel. This work presents spatially resolved measurements of CO emission collected with the Atacama Large Millimetre Array (ALMA) for 20 merging galaxies (either pairs or post-mergers) selected from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey. Eleven additional merging galaxies are selected from the ALMA MaNGA QUEnching and STar formation (AlMaQUEST) survey, resulting in a set of 31 mergers at various stages of interaction and covering a broad range of star formation rates (SFRs). We investigate galaxy-to-galaxy variations in the resolved Kennicutt-Schmidt relation, (rKS: Sigma(H2) versus Sigma(SFR)), the resolved molecular gas main sequence (rMGMS: Sigma(*) versus Sigma(SF)(R)), and the resolved star-forming main sequence (rSFMS: Sigma(*) versus Sigma(S)(FR)). We quantify offsets from these resolved relations to determine if SFR, molecular gas fraction, or/and SFE is/are enhanced in different regions of an individual galaxy. By comparing offsets in all three parameters, we can discern whether gas fraction or SFE powers an enhanced Sigma(SFR). We find that merger-induced star formation can be driven by a variety of mechanisms, both within a galaxy and between different mergers, regardless of interaction stage
Students\u27 Expert-Like Attitudes in Calculus and Introductory Computer Science Courses with Active-Learning Pedagogy
No full textBackground and Context: Computer Science has traditionally had poor student retention, especially among women. Prior work has found that student attitudes are a key factor to retention, especially with “weedout” courses such as Calculus.
Objective: To determine how student attitudes towards CS 1 and Calculus change over active-learning courses with explicit real-world connections, and the implications for at-risk groups in CS, including women and students without prior experience in CS.
Methods: We use two validated instruments, the Computer Attitudes Survey (CAS) and the Mathematics Attitudes and Perceptions Survey (MAPS), both of which derive from the Colorado Learning Attitudes about Science Survey (CLASS), to compare student attitudes in Calculus I and CS 1. Our analysis includes 109 students for the CAS and 73 for the MAPS.
Findings: CS 1 students began the course with CAS scores higher than observed in prior work, and post-course CAS scores were even higher overall. Calculus students started the course with MAPS scores in line with prior work, but unlike prior work we find that overall MAPS scores did not decline during the semester. Women’s reported interest in math increased significantly during the semester. Students with prior computer science experience began CS 1 with higher overall CAS scores, while students with prior calculus experience began Calculus with similar overall MAPS scores but much higher reported interest.
Implications: Difference in student attitudes between the courses may show why Calculus acts a “weedout” course for Computer Science. This highlights the importance of instructors demonstrating the usefulness of Calculus
Response of lake water nutrient condition to anthropogenic activities from 1871 to 2013 in the Jiuzhaigou World Natural Heritage Site, China
No full textOver the past century, lake degradation has increased around the world. Jiuzhaigou World Natural Heritage Site in southwestern China has been experiencing water nutrient enrichment, accelerated swamping, and algal biomass increases. These problems are likely associated with enhanced local anthropogenic activities over the past decades. In this study, radioactivities of Cs-137 and Pb-210, diatoms, and nutrient accumulation rates in a lake sediment core from Tiger Lake in Jiuzhaigou World Natural Heritage Site were used as proxies to reconstruct a \u3e 100-year record of environmental change to understand the extent and temporal variability of anthropogenic effects on lake water nutrients. Diatom communities reveal four distinct phases, relating to documented local human activities including (a) Primitive agriculture from 1871 to the mid-1930s, (b) Opium cultivation-logging from the mid-1930s to the mid-1970s, (c) Large-scale logging-the beginning of tourism from the mid-1970s to the early 1990s, and (d) Tourism development from the early 1990s to 2013. Nutrients in the lake (including total organic carbon, total nitrogen, and total phosphorus) steadily increased from 1871 until the late 1990s, declined from the late 1990s to the mid-2000s, and increased rapidly after the mid-2000s. Our data suggest that (a) Opium cultivation, deforestation, and tourism development led to the increase of lake nutrients and primary productivity, (b) Ecological protection measures taken from 1999 to 2004 effectively controlled water pollution, and (c) Post-2005 intensification of tourism further accelerated water quality deterioration. Additional monitoring and mitigation strategies are needed to further reduce nutrient input. Global studies suggest that while water quality of lakes in protected area is better than that of other lakes, care is still required to ensure that tourism activities do not inadvertently increase lake water nutrients