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1. An Anti-Anti-Turbulence Conjecture

   Dewar, W; Deremble, B (January 2021, Ocean and Coastal Research)

   null (Ed.)

   Sandstrom's theorem suggested that buoyancy fluxes can not drive the overturning circulation, an idea that physical oceanographers continue to debate. This paper attempts to provide the most fundamental examination of Sandstrom's theorem that is possible. We conclude that the fundamental role of buoyant forcing in the modern ocean is to damp the circulation, that buoyance fluxes drive significant levels of turbulence, that buoyant turbulent generation is not solely proportional to molecular diffusivity and that some of the main pathways to turbulence are non-Boussineq. We conjecture that the ocean might not be constrained by the `Anti-Turbulence' theorem. 

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2. Grass functional traits reflect the long history of fire and grazers in the savannas of Texas

   https://doi.org/10.1002/ajb2.70013  

   Nerlekar, Ashish N; Spalink, Daniel; Veldman, Joseph W (October 2025, American Journal of Botany)

   Abstract PremiseUnderstanding relationships among grass traits, fire, and herbivores may help improve conservation strategies for savannas that are threatened by novel disturbance regimes. Emerging theory, developed in Africa, emphasizes that functional traits of savanna grasses reflect the distinct ways that fire and grazers consume biomass. Specifically, functional trade‐offs related to flammability and palatability predict that highly flammable grass species will be unpalatable, while highly palatable species will impede fire. MethodsWe quantified six culm and leaf traits of 337 native grasses of Texas—a historical savanna region that has been transformed by fire exclusion, megafaunal extinctions, and domestic livestock. ResultsMultivariate analyses of traits revealed three functional strategies. “Grazer grasses” (N = 50) had culms that were short, narrow, and horizontal, and leaves with high width to length (W:L) and low C to N ratios (C:N)—trait values that attract grazers and avoid fire. “Fire grasses” (N = 104) had culms that were tall, thick, and upright, and leaves that were thick, with low W:L, and high C:N—trait values that promote fire and discourage grazers. “Generalist tolerators” and “generalist avoiders” (N = 183) had trait values that were intermediate to the other groups. ConclusionsOur findings confirm that the flammability–palatability trade‐offs that operate in Africa also explain correlated suites of traits in Texas grasses and highlights that the grass flora of Texas bears the signature of Pleistocene megafauna and the influence of fires that predate human arrival. We suggest that grass functional classifications based on fire and grazer traits can improve prescribed fire and livestock management of savannas of Texas and globally. 

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3. A tale of two Tagalogs

   https://doi.org/10.16995/glossa.11032  

   Pizarro-Guevara, Jed Sam; Wagers, Matthew (August 2024, Glossa: a journal of general linguistics)

   A well-received generalization in Tagalog is that only the argument that is cross-referenced by voice is eligible for A-bar extraction. However, recent work has shown that agents that are not cross-referenced by voice are also eligible. We provide naturally occurring data, along with experimental evidence, consistent with this more permissive picture. Further, we present computational evidence that participants were treating agent-extractions not cross-referenced by voice categorically, that is, they were either accepting or rejecting them in any given trial. Thus, we identify a piece of grammatical knowledge (i.e., extraction) that is systematic within an individual speaker but varies unpredictably across a population of Tagalog speakers. In other words, our data reveal two separable types of Tagalog speakers vis-à-vis extraction. We propose that this is a form of grammar competition that arises via the idea that the agent-first bias affects how child learners parse input strings under noisy conditions during acquisition. 

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4. Liquid-like condensates that bind actin drive filament polymerization and bundling

   https://doi.org/10.1101/2024.05.04.592527  

   Walker, Caleb; Chandrasekaran, Aravind; Mansour, Daniel; Graham, Kristin; Torres, Andrea; Wang, Liping; Lafer, Eileen M; Rangamani, Padmini; Stachowiak, Jeanne C (May 2024, bioRxiv)

   Liquid-like protein condensates perform diverse physiological functions. Previous work showed that VASP, a processive actin polymerase, forms condensates that polymerize and bundle actin. To minimize their curvature, filaments accumulated at the inner condensate surface, ultimately deforming the condensate into a rod-like shape, filled with a bundle of parallel filaments. Here we show that this behavior does not require proteins with specific polymerase activity. Specifically, we found that condensates composed of Lamellipodin, a protein that binds actin but is not an actin polymerase, were also capable of polymerizing and bundling actin filaments. To probe the minimum requirements for condensate-mediated actin bundling, we developed an agent-based computational model. Guided by its predictions, we hypothesized that any condensate-forming protein that binds actin could bundle filaments through multivalent crosslinking. To test this idea, we added an actin-binding motif to Eps15, a condensate-forming protein that does not normally bind actin. The resulting chimera formed condensates that drove efficient actin polymerization and bundling. Collectively, these findings broaden the family of proteins that could organize cytoskeletal filaments to include any actin-binding protein that participates in protein condensation. 

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5. Enabling Additional Parallelism in Asynchronous JavaScript Applications

   https://doi.org/10.4230/LIPIcs.ECOOP.2021.7  

   Arteca, Ellen; Tip, Frank; Schaefer, Max (July 2021, 35th European Conference on Object-Oriented Programming (ECOOP 2021))

   Sridharan, Manu (Ed.)

   JavaScript is a single-threaded programming language, so asynchronous programming is practiced out of necessity to ensure that applications remain responsive in the presence of user input or interactions with file systems and networks. However, many JavaScript applications execute in environments that do exhibit concurrency by, e.g., interacting with multiple or concurrent servers, or by using file systems managed by operating systems that support concurrent I/O. In this paper, we demonstrate that JavaScript programmers often schedule asynchronous I/O operations suboptimally, and that reordering such operations may yield significant performance benefits. Concretely, we define a static side-effect analysis that can be used to determine how asynchronous I/O operations can be refactored so that asynchronous I/O-related requests are made as early as possible, and so that the results of these requests are awaited as late as possible. While our static analysis is potentially unsound, we have not encountered any situations where it suggested reorderings that change program behavior. We evaluate the refactoring on 20 applications that perform file- or network-related I/O. For these applications, we observe average speedups ranging between 0.99% and 53.6% for the tests that execute refactored code (8.1% on average). 

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