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1. “The lab isn't life”: Black engineering graduate students reprioritize values at the intersection of two pandemics

   https://doi.org/10.1002/jee.20518  

   Coley, Brooke; Thomas, Katreena (April 2023, Journal of Engineering Education)

   Abstract BackgroundBlack engineering graduate students represent a critical and understudied population in engineering education. Gaining an understanding of the lived experiences of Black engineering graduate students while they are simultaneously weathering two pandemics, COVID‐19 and systemic racism, is of paramount importance. Purpose/HypothesisBlack engineering graduate students hold a unique duality, as both Black people in the United States and Black graduate students in US engineering programs that espouse white supremacist ideals. Their real‐world experiences necessitate understanding, and this paper highlights the related impact on the students themselves, their adaptations to the pandemics, and how those adaptations relate to and affect their support needs and navigation of their engineering academic environments. Design/MethodAn interpretive phenomenological analysis (IPA) approach was combined with community‐based participatory action research and was situated in Boykin's Triple Quandary. A family check‐in was conducted with 10 Black engineering graduate students enrolled in doctoral programs across the country to delve deep into their lived experience as a cultural community. ResultsFindings include an emergent framework of Black engineering graduate student values in response to the pandemics. These values aligned with the Black Cultural Ethos, demonstrating an adoption of collectivistic cultural values in times of crises. Further, COVID‐19 and systemic racism differentially impacted Black engineering graduate students and, thus, the manifestations of their values. ConclusionFor institutions to be able to effectively support their Black engineering graduate students, they must gain awareness of the students' experiences, values, and needs, in general, and amid crises specifically. The findings presented here provide a critical window into this information. 

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2. The assembly of the most rotationally supported disc galaxies in the TNG100 simulations

   https://doi.org/10.1051/0004-6361/202452209  

   Rodríguez, Silvio; Cristiani, Valeria A; Sales, Laura V; Abadi, Mario G (March 2025, Astronomy & Astrophysics)

   Context.Disc-dominated galaxies can be difficult to accommodate in a hierarchical formation scenario such as Λ cold dark matter (ΛCDM), where mergers are an important growth mechanism. However, observational evidence indicates that these galaxies are common in the Universe. Aims.We seek to characterise the conditions that lead to the formation of disc-dominated galaxies within ΛCDM. Methods.We used dynamical decomposition of the stellar particles in all galaxies with stellar massM_∗= [10¹⁰− 10¹¹] M_⊙within the cosmological hydrodynamical simulation Illustris TNG100. We selected a sample of 43 mostly-disc galaxies that have less than ∼10% of their mass in a bulge component. For comparison, we also studied two additional stellar-mass matched samples: 43 intermediate galaxies having ∼30% of their stellar mass in the bulge and 43 with a purely spheroidal-like morphology. Results.We find that the selection purely based on stellar dynamics is able to reproduce the expected stellar population trends of different morphological types, with higher star-formation rates and younger stars in disc-dominated galaxies. Halo spin seems to play no role in the morphology of the galaxies, in agreement with previous works. At a fixedM_*, our mostly-disc and intermediate samples form in dark matter haloes that are two to ten times less massive than the spheroidal sample, highlighting a higher efficiency in disc galaxies to retain and condensate their baryons. On average, mergers are less prevalent in the buildup of discs than in spheroidal galaxies, but there is a large scatter, including the existence of mostly-disc galaxies, with 15%–30% of their stars coming from accreted origin. Discs start to form early on, settling their low vertical velocity dispersion as early as 9–10 Gyr ago, although the dominance of the disc over the spheroid was established more recently (3–4 Gyr lookback time). The most rotationally supported discs form in haloes with the lowest virial mass in the sample and the best aligned distribution of angular momentum in the gas. 

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3. Market Discipline in the Direct Lending Space

   https://doi.org/10.1093/rfs/hhad081  

   Davydiuk, Tetiana; Marchuk, Tatyana; Rosen, Samuel; Matvos, ed., Gregor (October 2023, The Review of Financial Studies)

   Abstract Using the exclusion of business development companies (BDCs) from stock indexes, this paper studies the effectiveness of market discipline in the direct lending space. Amid share sell-offs by institutional investors, a drop in BDCs’ valuations limits their ability to raise new equity capital. Following this funding shock, BDCs do not adjust their capital structure. At the same time, they are reducing the risk exposure of their portfolios. We document a greater reduction in risk for BDCs subject to stronger market discipline from their debtholders. BDCs pass through the capital shock to their portfolio firms by reducing their investment intensity. 

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4. Grinding and the anisotropic environment: influences on the diastereoselective formation of Group 15 allyl complexes

   https://doi.org/10.1039/D4MR00001C  

   Wenger, Lauren E; Hanusa, Timothy P (July 2024, RSC Mechanochemistry)

   Layered solids (AsI₃, SbCl₃) can serve as templates for diastereomer formation, and mechanochemical variables can shift their ratios. 

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5. Benthic invaders control the phosphorus cycle in the world’s largest freshwater ecosystem

   https://doi.org/10.1073/pnas.2008223118  

   Li, Jiying; Ianaiev, Vadym; Huff, Audrey; Zalusky, John; Ozersky, Ted; Katsev, Sergei (January 2021, Proceedings of the National Academy of Sciences)

   The productivity of aquatic ecosystems depends on the supply of limiting nutrients. The invasion of the Laurentian Great Lakes, the world’s largest freshwater ecosystem, by dreissenid (zebra and quagga) mussels has dramatically altered the ecology of these lakes. A key open question is how dreissenids affect the cycling of phosphorus (P), the nutrient that limits productivity in the Great Lakes. We show that a single species, the quagga mussel, is now the primary regulator of P cycling in the lower four Great Lakes. By virtue of their enormous biomass, quagga mussels sequester large quantities of P in their tissues and dramatically intensify benthic P exchanges. Mass balance analysis reveals a previously unrecognized sensitivity of the Great Lakes ecosystem, where P availability is now regulated by the dynamics of mussel populations while the role of the external inputs of phosphorus is suppressed. Our results show that a single invasive species can have dramatic consequences for geochemical cycles even in the world’s largest aquatic ecosystems. The ongoing spread of dreissenids across a multitude of lakes in North America and Europe is likely to affect carbon and nutrient cycling in these systems for many decades, with important implications for water quality management. 

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