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Cavitation bubbles often appear as populations in a wide range of naval and biomedical applications. While the oscillations of an isolated spherical bubble are relatively well understood, the dynamics of multiple bubbles remain less characterized due to the large number of parameters associated with bubble size and spatial configuration. In the present study, we develop an energy budget framework for quantifying energy transfer and pressure work during the oscillations of spherical bubbles while conserving the total energy of the system. We focus on a two-bubble system in the dilute limit, in which bubbles interact weakly and largely maintain spherical symmetry. The energy budget framework uses the outputs of the coupled Keller–Miksis equations to evaluate individual energy components and their temporal evolution. Three key parameters—bubble size ratio, bubble–bubble distance, and driving pressure ratio—are observed to nonlinearly alter collapse time, energy concentration, and radiated acoustic energy. We show that stronger interactions, caused by larger size ratios or smaller separation distances, lead to reduced compression and less violent and delayed collapse, thereby lowering the energy concentrated in the bubble. We further determine scaling relationships for bubble dynamics and energy components at the instant of collapse based on the initial problem parameters. We identify the initial driving pressure conditions where the dominant energy reduction mechanism shifts from bubble–bubble interactions at low driving pressures to liquid compressibility at high pressures. The proposed framework and scaling relations provide a robust basis for incorporating bubble–bubble interactions and energy redistribution mechanisms into bubble cloud models, in the dilute limit. 

We examined teachers’ development of adaptive expertise of mathematics language routines (MLRs) as they engaged in Studio Day professional learning focused on the MLR Compare and Connect. We collected video data from pre- and post-Studio Day meetings, as well as debriefs and their lesson enactments. We analyzed the data using three dimensions of adaptive expertise: flexibility, deeper level of understanding, and deliberate practice. We share a case study of a teacher exhibiting dimensions of adaptive expertise during the Studio Day Cycle through the use of a gallery walk. The teacher’s enactment of the MLR Compare and Connect provides an image of a teacher’s adaptive expertise of this MLR and helps us understand these MLRs and how teachers use and make sense of them in their instruction. 

Our work uses Studio Day Cycles (Von Esch & Kavanagh, 2018) focused on the integration and development of mathematics language routines (MLRs; Zweirs et al., 2017). Our conceptual framework draws on two key ideas: communities of practice (Lave & Wenger, 1991) and teacher communities (CoP; Grossman et al., 2001). We discuss each and how they interact with each other. Therefore, our research question was: How, if at all, did a Studio Day Cycle establish a teacher learning community to support teachers to engage in reflection around use of the MLRs? 

Backscatter power measurements are collected to characterize indoor radar clutter in monostatic sensing applications. A narrowband 28 GHz sounder used a quasimonostatic radar arrangement with an omnidirectional transmit antenna illuminating an indoor scene and a spinning horn receive antenna offset vertically (less than 1 m away) collecting backscattered power as a function of azimuth. Power variation in azimuth around the local average is found to be within 1 dB of a lognormal distribution with a standard deviation of 6.8 dB. Backscatter azimuth spectra are found to be highly variable with location, with cross-correlation coefficients on the order of 0.3 at separations as small as 0.1 m. These statistics are needed for system-level evaluation of RF sensing performance. 

Backscatter power measurements are collected to characterize indoor radar clutter in monostatic sensing applications. A narrowband 28 GHz sounder used a quasi-monostatic radar arrangement with an omnidirectional transmit antenna illuminating an indoor scene and a spinning horn receive antenna offset vertically (less than 1 m away) collecting backscattered power as a function of azimuth. Power variation in azimuth around the local average is found to be within 1 dB of a lognormal distribution with a standard deviation of 6.8 dB. Backscatter azimuth spectra are found to be highly variable with location, with cross-correlation coefficients on the order of 0.3 at separations as small as 0.1 m. These statistics are needed for system-level evaluation of RF sensing performance. 

Engaging teachers in reflective practices is recognized as a crucial component of their adaptive expertise development. Drawing on this perspective of adaptive expertise development, we qualitatively examined how the design and structure of a Studio Day professional learning cycle afforded opportunities for reflective practice for secondary in-service mathematics teachers. We found that small group reflections, immediate reflections-on-action, and the use of videos afforded notable instances of reflective practices throughout the Studio Day Cycle that supported teachers’ development of adaptive expertise of equity-based, language-responsive teaching. We suggest that Studio Day Cycles are one avenue to better support in-service teachers’ development of adaptive expertise of mathematics language routines and multilingual learner core practices. 

Abstract Quantum Chromodynamics predicts a phase transition from hadronic matter to quark–gluon plasma (QGP) at high temperatures and energy densities, where quarks and gluons (partons) are no longer confined within hadrons. The QGP forms in ultrarelativistic heavy-ion collisions. Anisotropic flow coefficients, quantifying the azimuthal expansion of produced matter, probe QGP properties. Flow measurements in high-energy heavy-ion collisions show a distinctive grouping of anisotropic flow for baryons and mesons at intermediate transverse momentum – a feature associated with flow imparted at the quark level, confirming QGP existence. The observation of QGP-like features in proton–proton and proton–ion collisions has sparked debate about QGP formation in smaller systems. For the first time, we demonstrate the distinctive grouping of anisotropic flow for baryons and mesons in high-multiplicity proton–lead and proton–proton collisions at the Large Hadron Collider (LHC). These results are described by a model including hydrodynamic flow followed by hadron formation via quark coalescence, consistent with the formation of partonic flowing systems in these collisions. 

ABSTRACT The future detection of gravitational waves (GWs) from a Galactic core-collapse supernova will provide information on the physics inside protoneutron stars (PNS). In this work, we apply three different classification methods for the PNS non-radial oscillation modes: Cowling classification, Generalized Cowling Nomenclature (GCN), and a classification based on modal properties (CBMP). Using PNS models from 3D simulations of core-collapse supernovae, we find that in the early stages of the PNS evolution, typically 0.4 s after the bounce, the Cowling classification is inconsistent, but the GCN and the CBMP provide complementary information that helps to understand the evolution of the modes. In the GCN, we note several avoided crossings as the mode frequencies evolve at early times, while the CBMP tracks the modes across the avoided crossings. We verify that the strongest emission of GWs by the PNS corresponds to the f mode in the GCN, indicating that the mode trapping region alternates between the core and the envelope at each avoided crossing. At later times, approximately 0.4 s after the bounce, the three classification methods present a similar description of the mode spectrum. We use our results to test universal relations for the PNS modes according to their classification and find that the behaviour of the universal relations for f and p modes is remarkably simple in the CBMP. 

Marine coccolithophores are globally distributed, unicellular phytoplankton that produce nanopatterned, calcite biominerals (coccoliths). These biominerals are synthesized internally, deposited into an extracellular coccosphere, and routinely released into the external medium, where they profoundly affect the global carbon cycle. The cellular costs and benefits of calcification remain unresolved. Here, we show observational and experimental evidence, supported by biophysical modeling, that free coccoliths are highly adsorptive biominerals that readily interact with cells to form chimeric coccospheres and with viruses to form “viroliths,” which facilitate infection. Adsorption to cells is mediated by organic matter associated with the coccolith base plate and varies with biomineral morphology. Biomineral hitchhiking increases host-virus encounters by nearly an order of magnitude and can be the dominant mode of infection under stormy conditions, fundamentally altering how we view biomineral-cell-virus interactions in the environment.