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1. Simulating Long‐Term Dynamics of Radiation Belt Electrons Using DREAM3D Model

   https://doi.org/10.1029/2023JA032286  

   Lee, Sang‐Yun; Tu, Weichao; Cunningham, Gregory S; Cowee, Misa M; Wang, Dedong; Shprits, Yuri Y; Henderson, Michael G; Reeves, Geoffrey D (February 2024, Journal of Geophysical Research: Space Physics)

   Abstract We compared the performance of DREAM3D simulations in reproducing the long‐term radiation belt dynamics observed by Van Allen Probes over the entire year of 2017 with various boundary conditions (BCs) and model inputs. Specifically, we investigated the effects of three different outer boundary conditions, two different low‐energy boundary conditions for seed electrons, four different radial diffusion (RD) coefficients (D_LL), four hiss wave models, and two chorus wave models from the literature. Using the outer boundary condition driven by GOES data, our benchmark simulation generally well reproduces the observed radiation belt dynamics insideL* = 6, with a better model performance at lowerμthan higherμ, whereμis the first adiabatic invariant. By varying the boundary conditions and inputs, we find that: (a) The data‐driven outer boundary condition is critical to the model performance, while adding in the data‐driven seed population doesn't further improve the performance. (b) The model shows comparable performance withD_LLfrom Brautigam and Albert (2000,https://doi.org/10.1029/1999ja900344), Ozeke et al. (2014,https://doi.org/10.1002/2013ja019204), and Liu et al. (2016,https://doi.org/10.1002/2015gl067398), while withD_LLfrom Ali et al. (2016,https://doi.org/10.1002/2016ja023002) the model shows less RD compared to data. (c) The model performance is similar with data‐based hiss models, but the results show faster loss is still needed inside the plasmasphere. (d) The model performs similarly with the two different chorus models, but better capturing the electron enhancement at higherμusing the Wang et al. (2019,https://doi.org/10.1029/2018ja026183) model due to its stronger wave power, since local heating for higher energy electrons is under‐reproduced in the current model. 

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2. Recognition of Design Failure by Fourth Grade Students During an Engineering Design Challenge

   Skinner, R. & (October 2022, In 2022 ASEE Annual Conference)

   The practice of persisting and learning from design failures is essential to engineering design and offers unique ways of knowing and learning for K-12 students. To understand how students engage in the practice of persisting and learning from design failures, we must first understand how, if at all, they recognize that a design failure has occurred. We studied a classroom of fourth grade students engaged in an engineering design challenge and examined the ways in which design failure occurred and how students recognized, neglected to recognize, or misinterpreted design failure. In addition to anticipating failure, conducting fair tests, and making focused observations, we found that students must have an understanding and awareness of the evolving criteria and constraints of the design problem in order to recognize design failure. If lacking an understanding and awareness of criteria and constraints represents a barrier to recognizing an initial design failure, it also represents a barrier to recognizing any subsequent design failures in the design process and thus a barrier to persisting and learning from design failures. 

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3. Fractionalized Fermi liquids and the cuprate phase diagram

   https://doi.org/10.1088/1361-6633/ae530d  

   Bonetti, Pietro M; Christos, Maine; Nikolaenko, Alexander; Patel, Aavishkar A; Sachdev, Subir (April 2026, Reports on Progress in Physics)

   Abstract We review a theoretical framework for the cuprate superconductors, rooted in a fractionalized Fermi liquid (FL*) description of the intermediate-temperature pseudogap phase at low doping. The FL* theory predicted hole pockets each of fractional area $p/8$ at hole dopingp, in contrast to the area $p/4$ in spin density wave theory. Magnetotransport measurements, including observation of the Yamaji angle, show clear evidence of hole pocket quasiparticles which can tunnel coherently between square lattice layers, and are consistent with the FL* description. The FL* phase of a single-band model is described using a layer construction with a pair of ancilla qubits on each site: the Ancilla layer model (ALM). Its mean field theory yields hole pockets of area $p/8$ , and matches the gapped photoemission spectrum in the anti-nodal region of the Brillouin zone. Fluctuations are described by the SU(2) gauge theory of a background spin liquid with critical Dirac spinons. A Monte Carlo study of the thermal SU(2) gauge theory transforms the hole pockets into Fermi arcs in photoemission. One route to confinement of FL* upon lowering temperature yields ad-wave superconductor via a Kosterlitz–Thouless transition of $h/\left(2e\right)$ vortices, with nodal Bogoliubov quasiparticles featuring anisotropic velocities and vortices surrounded by charge order halos. An alternative route yields a charge-ordered metallic state that has quantum oscillations consistent with observations. These confinement transitions are driven by the condensation of a SU(2) fundamental Higgs field, which also provides a fractionalized description of intertwined orders. Increasing doping from the FL* phase in the ALM drives a transition to a conventional FL at large doping, passing through an intermediate strange metal regime. We formulate a theory of the FL*-FL metal-metal transition without a symmetry-breaking order parameter, using a critical quantum ‘charge’ liquid of mobile electrons in the presence of disorder, developed via an extension of the Sachdev–Ye–Kitaev model to two spatial dimensions. At low temperatures, and across optimal and over doping, we address the regimes of extended non-FL behavior by Griffiths effects near quantum phase transitions in disordered metals. Partly based on lectures by S S atBoulder School 2025, Dynamics of Strongly Correlated Electrons, 14–18 July.Lecture videos.Joint ICTP-WE Heraeus School and Workshop on Advances in Quantum Matter: Pushing the Boundaries, ICTP, Trieste, 4, 6 August 2025.Lecture videos.School on Quantum Dynamics of Matter, Light and Information, ICTP, Trieste, 18, 19 August 2025.Lecture videos.Croucher Advanced Study Institute for Fractional Chern Insulators, University of Hong Kong, 4, 5 September 2025.Lecture slides.Advanced School and Conference on Quantum Matter, ICTP Trieste, 1–12 December 2025.Lecture Notes.Lecture videos. 

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4. Examining the Potential of Cartoon-Based Simulations for Studying Mathematics Teachers’ Handling of Student Emotions: A Replication Study

   https://doi.org/10.1163/26670127-bja10013  

   Brown, A M; Bardelli, E; Herbst, P G; Dimmel, J K (November 2023, Implementation and Replication Studies in Mathematics Education)

   Abstract Technology-mediated simulations of teaching are used increasingly to represent practice in the context of professional development interventions and assessment. Some such simulations represent students as cartoon characters. An important question in this context is whether simplified cartoon representations of students can convey similar meanings as real facial expressions do. Here, we share results from an implementation and replication study designed to observe whether and how (1) cartoon-based representations of emotion using graphical facial expressions can be interpreted at similar levels of accuracy as photo representations of emotions using actors and (2) the inclusion of markers of student emotions in storyboard-based scenarios of secondary mathematics teaching affects teachers’ appropriateness rating of the actions taken by a teacher represented in the storyboard. We show graphical representations of emotions can evoke particular intended emotions and that markers of student emotions in representations of practice could cue mathematics teachers into particular judgments of action. The Impact Sheet to this article can be accessed at10.6084/m9.figshare.24219964 

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5. Reductive evolution and genomic reduction in Rhodopseudomonas

   https://doi.org/10.1128/aem.00445-25  

   Gallagher, Brian M; Morrison, Hailee M; Bose, Arpita (August 2025, Applied and Environmental Microbiology)

   Reguera, Gemma (Ed.)

   ABSTRACT Rhodopseudomonas palustrisis renowned for its metabolic versatility, supported by a genome that contains pathways for numerous processes. In a recent study, Oda et al. (Appl Environ Microbiol 91:e02056-24, 2025,https://doi.org/10.1128/aem.02056-24) examineR. palustrisDSM127, a strain with a dramatically reduced gene inventory, to study how environmental pressures have influenced gene loss. Missing more than a quarter of its genome reduces its versatility. However, it may improve its efficiency under the conditions in which it still thrives, enhancing its aptitude as a chassis for biotechnology. 

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