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Messa di Requiem
No full textPerforming score: Nino Rota (Composer), Jonathan Hirsh (Arranger)
Messa di Requiem for organ and voices (SATB) edited by Jonathan Hirsh organ and mixed choir (SATB)https://scholarworks.smith.edu/mus_books/1001/thumbnail.jp
Public School Funding and Juvenile Crime: Evidence from New York City
No full textJuvenile crime is a pressing issue in the US, with individuals of age below 18 making up over 5% of all murder offenders across the nation. This paper examines the effect of public school funding on juvenile crime on school premises in New York City. Namely, I use the introduction of Fair Student Funding (FSF) in the 2007-2008 academic year as an exogenous shock to per-student expenditure. By taking the student needs into account, FSF intended to increase the funding for underfunded schools while keeping the allocations the same for overfunded schools. I do not find a statistically significant effect of FSF on juvenile crime on school premises. However, the direction of the coefficient estimates is positive, which indicates that crime might have increased post- FSF. The increase in crime might be explained by the crime-inducing effects of the 2008 financial crisis that was followed by a recession
The Geologic History of Primary Productivity
Get PDFThe rate of primary productivity is a keystone variable in driving biogeochemical cycles today and has been throughout Earth’s past.1 For example, it plays a critical role in determining nutrient stoichiometry in the oceans,2 the amount of global biomass,3 and the composition of Earth’s atmosphere.4 Modern estimates suggest that terrestrial and marine realms contribute near-equal amounts to global gross primary productivity (GPP).5 However, this productivity balance has shifted significantly in both recent times6 and through deep time.7,8 Combining the marine and terrestrial components, modern GPP fixes ≈250 billion tonnes of carbon per year (Gt C year−1).5,9,10,11 A grand challenge in the study of the history of life on Earth has been to constrain the trajectory that connects present-day productivity to the origin of life. Here, we address this gap by piecing together estimates of primary productivity from the origin of life to the present day. We estimate that ∼1011–1012 Gt C has cumulatively been fixed through GPP (≈100 times greater than Earth’s entire carbon stock). We further estimate that 1039–1040 cells have occupied the Earth to date, that more autotrophs than heterotrophs have ever existed, and that cyanobacteria likely account for a larger proportion than any other group in terms of the number of cells. We discuss implications for evolutionary trajectories and highlight the early Proterozoic, which encompasses the Great Oxidation Event (GOE), as the time where most uncertainty exists regarding the quantitative census presented here
The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems I: High-contrast Imaging of the Exoplanet HIP 65426 b from 2 to 16 μm
Get PDFWe present JWST Early Release Science coronagraphic observations of the super-Jupiter exoplanet, HIP 65426b, with the Near-Infrared Camera (NIRCam) from 2 to 5 μm, and with the Mid-Infrared Instrument (MIRI) from 11 to 16 μm. At a separation of ∼0.″82 (87 − 31 + 108 au), HIP 65426b is clearly detected in all seven of our observational filters, representing the first images of an exoplanet to be obtained by JWST, and the first-ever direct detection of an exoplanet beyond 5 μm. These observations demonstrate that JWST is exceeding its nominal predicted performance by up to a factor of 10, depending on separation and subtraction method, with measured 5σ contrast limits of ∼1 × 10−5 and ∼2 × 10−4 at 1″ for NIRCam at 4.4 μm and MIRI at 11.3 μm, respectively. These contrast limits provide sensitivity to sub-Jupiter companions with masses as low as 0.3M Jup beyond separations of ∼100 au. Together with existing ground-based near-infrared data, the JWST photometry are fit well by a BT-SETTL atmospheric model from 1 to 16 μm, and they span ∼97% of HIP 65426b\u27s luminous range. Independent of the choice of model atmosphere, we measure an empirical bolometric luminosity that is tightly constrained between log L bol / L ⊙ = −4.31 and −4.14, which in turn provides a robust mass constraint of 7.1 ± 1.2 M Jup. In totality, these observations confirm that JWST presents a powerful and exciting opportunity to characterize the population of exoplanets amenable to high-contrast imaging in greater detail
Elucidating Interprotein Energy Transfer Dynamics Within the Antenna Network from Purple Bacteria
Get PDFIn photosynthesis, absorbed light energy transfers through a network of antenna proteins with near-unity quantum efficiency to reach the reaction center, which initiates the downstream biochemical reactions. While the energy transfer dynamics within individual antenna proteins have been extensively studied over the past decades, the dynamics between the proteins are poorly understood due to the heterogeneous organization of the network. Previously reported timescales averaged over such heterogeneity, obscuring individual interprotein energy transfer steps. Here, we isolated and interrogated interprotein energy transfer by embedding two variants of the primary antenna protein from purple bacteria, light-harvesting complex 2 (LH2), together into a near-native membrane disc, known as a nanodisc. We integrated ultrafast transient absorption spectroscopy, quantum dynamics simulations, and cryogenic electron microscopy to determine interprotein energy transfer timescales. By varying the diameter of the nanodiscs, we replicated a range of distances between the proteins. The closest distance possible between neighboring LH2, which is the most common in native membranes, is 25 Å and resulted in a timescale of 5.7 ps. Larger distances of 28 to 31 Å resulted in timescales of 10 to 14 ps. Corresponding simulations showed that the fast energy transfer steps between closely spaced LH2 increase transport distances by ∼15%. Overall, our results introduce a framework for well-controlled studies of interprotein energy transfer dynamics and suggest that protein pairs serve as the primary pathway for the efficient transport of solar energy
Transcranial Magnetic Stimulation to the Angular Gyrus Modulates the Temporal Dynamics of the Hippocampus and Entorhinal Cortex
Get PDFTranscranial magnetic stimulation (TMS) delivered to the angular gyrus (AG) affects hippocampal function and associated behaviors (Thakral PP, Madore KP, Kalinowski SE, Schacter DL. Modulation of hippocampal brain networks produces changes in episodic simulation and divergent thinking. 2020a. Proc Natl Acad Sci U S A. 117:12729-12740). Here, we examine if functional magnetic resonance imaging (fMRI)-guided TMS disrupts the gradient organization of temporal signal properties, known as the temporal organization, in the hippocampus (HPC) and entorhinal cortex (ERC). For each of 2 TMS sessions, TMS was applied to either a control site (vertex) or to a left AG target region (N = 18; 14 females). Behavioral measures were then administered, and resting-state scans were acquired. Temporal dynamics were measured by tracking change in the fMRI signal (i) within single voxels over time, termed single-voxel autocorrelation and (ii) between different voxels over time, termed intervoxel similarity. TMS reduced AG connectivity with the hippocampal target and induced more rapid shifting of activity in single voxels between successive time points, lowering the single-voxel autocorrelation, within the left anteromedial HPC and posteromedial ERC. Intervoxel similarity was only marginally affected by TMS. Our findings suggest that hippocampal-targeted TMS disrupts the functional properties of the target site along the anterior/posterior axis. Further studies should examine the consequences of altering the temporal dynamics of these medial temporal areas to the successful processing of episodic information under task demand
Editorial: Professional and Scientific Societies Impacting Diversity, Equity and Inclusion in Stemm
Get PDFIntegration Host Factor Binds Dna Holliday Junctions
Get PDFIntegration host factor (IHF) is a nucleoid-associated protein involved in DNA packaging, integration of viral DNA and recombination. IHF binds with nanomolar affinity to duplex DNA containing a 13 bp consensus sequence, inducing a bend of ~160° upon binding. We determined that IHF binds to DNA Four-way or Holliday junctions (HJ) with high affinity regardless of the presence of the consensus sequence, signifying a structure-based mechanism of recognition. Junctions, important intermediates in DNA repair and homologous recombination, are dynamic and can adopt either an open or stacked conformation, where the open conformation facilitates branch migration and strand exchange. Using ensemble and single molecule Förster resonance energy transfer (FRET) methods, we investigated IHF-induced changes in the population distribution of junction conformations and determined that IHF binding shifts the population to the open conformation. Further analysis of smFRET dynamics revealed that even in the presence of protein, the junctions remain dynamic as fast transitions are observed for the protein-bound open state. Protein binding alters junction conformational dynamics, as cross correlation analyses reveal the protein slows the transition rate at 1 mM Mg2+ but accelerates the transition rate at 10 mM Mg2+. Stopped flow kinetic experiments provide evidence for two binding steps, a rapid, initial binding step followed by a slower step potentially associated with a conformational change. These measurements also confirm that the protein remains bound to the junction during the conformer transitions and further suggest that the protein forms a partially dissociated state that allows junction arms to be dynamic. These findings, which demonstrate that IHF binds HJs with high affinity and stabilizes junctions in the open conformation, suggest that IHF may play multiple roles in the processes of integration and recombination in addition to stabilizing bacterial biofilms
The Caribbean as Diaspora: From Exile to Affirmation
No full textCaribbean art as a diasporic, fugitive phenomenon: a groundbreaking global survey.
The 1990s were a period of profound political transformation, from the dissolution of the Eastern Bloc to the rise of trade agreements that continue to influence the world we live in today. Emerging from this pivotal decade—which also shaped the production, circulation and framing of art in the Caribbean—Forecast Form traces a path into the present, highlighting forms, materials and processes that reveal new modes of thinking about identity and place.
This volume features scholarly essays alongside richly illustrated plate sections and texts focused on an intergenerational group of 37 artists working across the Americas and Europe. A radical rethinking of contemporary art in the Caribbean, Forecast Form reveals the region as a place where the past, the present and the future meet—where continuous exchanges forecast what is to come while remaining grounded in the histories that shape the present.
Artists include: Candida Alvarez, Firelei Báez, Álvaro Barrios, Frank Bowling, Sandra Brewster, María Magdalena Campos-Pons, Donna Conlon and Jonathan Harker, Christopher Cozier, Julien Creuzet, Maksaens Denis, Peter Doig, Jeannette Ehlers, Tomm El-Saieh, Alia Farid, Teresita Fernández, Rafael Ferrer, Denzil Forrester, Joscelyn Gardner, Felix Gonzalez-Torres, Deborah Jack, Engel Leonardo, Daniel Lind-Ramos, Suchitra Mattai, David Medalla, Ana Mendieta, Lorraine O\u27Grady, Ebony G. Patterson, Keith Piper, Marton Robinson, Donald Rodney, Freddy Rodríguez, Tavares Strachan, Zilia Sánchez, Rubem Valentim, Adán Vallecillo, Cosmo Whyte and Didier William.
Authors: Carla Acevedo-Yates, Genevieve Hyacinthe, and Aaron Kamugishahttps://scholarworks.smith.edu/afr_books/1004/thumbnail.jp
African Union Reform: Challenges and Opportunities
No full textChapter Abstract:
This chapter considers institutional reform of the African Union (AU). There are three causes that limit the progress of institutional reform in the AU: first, are the internal political factors that impact leader’s ability to manage their positions in the region (clout); inconsistency in how AU leaders prioritize certain issues (commitment); and inconsistency in the application of AU rules and norms (credibility). Considering these “3Cs,” this chapter considers how issues of institutional design, informality, and a lack of civic involvement condition the progress toward institutional reform. This chapter examines two pathways to overcome reform challenges: (1) improved institutional synergy and a clear division of labor between the African Union Assembly Heads, the African Union Commission, and Regional Economic Communities; and (2) strengthening of diplomatic ties with domestic institutions and civil society through an empowered practitioner class. These pathways create the conditions for a more inclusive regional governance structure in Africa.
Book Summary:
In this handbook, a group of 40 scholars and practitioners from some 30 countries takes a critical look at the contemporary practice of diplomacy. Many assume diplomacy evolves naturally, and that state- and non-state actors are powerless to make significant changes. But Diplomacy\u27s methods, its key institutions and conventions were agreed more than six decades ago. None take account of the opportunities and vulnerabilities presented by the Internet. Diplomacy is now a neglected global issue. The COVID pandemic and the invasion of Ukraine have highlighted some of the problems of diplomatic dysfunction. Beyond identifying current problems diplomacy is facing, the book also seeks to identify some practical options for reform and innovation. How might a process of reform be agreed and implemented? What role might the United Nations, regional organizations and Big Tech play? How can new norms of diplomatic behavior and methods be established in a multipolar, digital world where diplomacy is seen as less and less effective? Paul Webster Hare is Senior Lecturer in International Relations at the Frederick S. Pardee School of Global Studies, Boston University, USA. He was a diplomat for 30 years and British ambassador to Cuba from 2001 to 2004. Juan Luis Manfredi-Sánchez is Prince of Asturias Distinguished Visiting Professor at the School of Foreign Service, Georgetown University, USA, and Professor at the University of Castilla-La Mancha, Spain. Kenneth Weisbrode is Assistant Professor of History at Bilkent University, Turkey.https://scholarworks.smith.edu/gov_books/1010/thumbnail.jp