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Background Team leadership during medical emergencies like cardiac arrest resuscitation is cognitively demanding, especially for trainees. These cognitive processes remain poorly characterized due to measurement challenges. Using virtual reality simulation, this study aimed to elucidate and compare communication and cognitive processes-such as decision-making, cognitive load, perceived pitfalls, and strategies-between expert and novice code team leaders to inform strategies for accelerating proficiency development. Methods A simulation-based mixed methods approach was utilized within a single large academic medical center, involving twelve standardized virtual reality cardiac arrest simulations. These 10- to 15-minutes simulation sessions were performed by seven experts and five novices. Following the simulations, a cognitive task analysis was conducted using a cued-recall protocol to identify the challenges, decision-making processes, and cognitive load experienced across the seven stages of each simulation. Results The analysis revealed 250 unique cognitive processes. In terms of reasoning patterns, experts used inductive reasoning, while novices tended to use deductive reasoning, considering treatments before assessments. Experts also demonstrated earlier consideration of potential reversible causes of cardiac arrest. Regarding team communication, experts reported more critical communications, with no shared subthemes between groups. Experts identified more teamwork pitfalls, and suggested more strategies compared to novices. For cognitive load, experts reported lower median cognitive load (53) compared to novices (80) across all stages, with the exception of the initial presentation phase. Conclusions The identified patterns of expert performance — superior teamwork skills, inductive clinical reasoning, and distributed cognitive strategiesn — can inform training programs aimed at accelerating expertise development. 

Linear representation learning is widely studied due to its conceptual simplicity and empirical utility in tasks such as compression, classification, and feature extraction. Given a set of points $$[\x_1, \x_2, \ldots, \x_n] = \X \in \R^{d \times n}$$ and a vector $$\y \in \R^d$$, the goal is to find coefficients $$\w \in \R^n$$ so that $$\X \w \approx \y$$, subject to some desired structure on $$\w$$. In this work we seek $$\w$$ that forms a local reconstruction of $$\y$$ by solving a regularized least squares regression problem. We obtain local solutions through a locality function that promotes the use of columns of $$\X$$ that are close to $$\y$$ when used as a regularization term. We prove that, for all levels of regularization and under a mild condition that the columns of $$\X$$ have a unique Delaunay triangulation, the optimal coefficients' number of non-zero entries is upper bounded by $d+1$, thereby providing local sparse solutions when $$d \ll n$$. Under the same condition we also show that for any $$\y$$ contained in the convex hull of $$\X$$ there exists a regime of regularization parameter such that the optimal coefficients are supported on the vertices of the Delaunay simplex containing $$\y$$. This provides an interpretation of the sparsity as having structure obtained implicitly from the Delaunay triangulation of $$\X$$. We demonstrate that our locality regularized problem can be solved in comparable time to other methods that identify the containing Delaunay simplex. 

On 10 May 2024, a series of coronal mass ejections were detected at Earth followed by one of the most powerful geomagnetic storms since November 2003. Leveraging a multi–technique approach, this paper provides an account of the ground geomagnetic response during the 10–11 May 2024 extreme geomagnetic storm. More specifically, we show that at the mid-latitudes in the American sector, the storm produced extreme ground geomagnetic field perturbations between 01:50 UT and 02:30 UT on 11 May. Then using the Spherical Elementary Current System method, it is shown that the perturbations were associated with an intense westward propagating auroral westward electrojet current. Finally, with the aid of auroral all-sky images from the Missouri Skies Observatory, we demonstrate that an intense isolated substorm event with onset located between the Great Lakes region and the East Coast United States was the main source of the extreme westward electrojet current and the geomagnetic field perturbations at these typical mid-latitude locations. This study emphasizes the increased risk associated with expansion of the auroral oval into the mid-latitudes during extreme geomagnetic activity. 

This study introduces AutoCLC, an AI-powered system designed to assess and provide feedback on closed-loop communication (CLC) in professional learning environments. CLC, where a sender’s Call-Out statement is acknowledged by the receiver’s Check-Back statement, is a critical safety protocol in high-reliability domains, including emergency medicine resuscitation teams. Existing methods for evaluating CLC lack quantifiable metrics and depend heavily on human observation. AutoCLC addresses these limitations by leveraging natural language processing and large language models to analyze audio recordings from Advanced Cardiovascular Life Support (ACLS) simulation training. The system identifies CLC instances, measures their frequency and rate per minute, and categorizes communications as effective, incomplete, or missed. Technical evaluations demonstrate AutoCLC achieves 78.9% precision for identifying Call-Outs and 74.3% for Check-Backs, with a performance gap of only 5% compared to human annotations. A user study involving 11 cardiac arrest instructors across three training sites supported the need for automated CLC assessment. Instructors found AutoCLC reports valuable for quantifying CLC frequency and quality, as well as for providing actionable, example-based feedback. Participants rated AutoCLC highly, with a System Usability Scale score of 76.4%, reflecting above-average usability. This work represents a significant step toward developing scalable, data-driven feedback systems that enhance individual skills and team performance in high-reliability settings. 

We report the two-dimensional (2D) bimetallic selenophosphate, LiGaP2Se6, prepared through direct combination reactions and P2Se5 flux methods. The material is a member of the broad class of van der Waals 2D materials of the type M2P2Q6 (M = metals). The structure was determined using single-crystal X-ray diffraction and refined in the chiral space group P3̅1c, with lattice parameters a = b = 6.2993(9) Å, c = 13.308(3) Å, α = β = 90°, γ = 120°. Differential thermal analysis indicated a congruent melting point at ∼458 °C. Optoelectronic properties were assessed using ultraviolet–visible (UV–vis) spectroscopy, showing a band gap of 2.01 eV, and photoemission yield spectroscopy in air (PYSA), which determined a work function of 5.44 eV. Notably, stability studies on LiGaP2Se6 revealed remarkable resilience despite its Li content, showing no structural changes after 2 weeks in ambient air or after soaking in a water/ethanol bath. 

Abstract Laser ablation is a process that bears both fundamental physics interest and has wide industrial applications. For decades, the lack of probes on the relevant time and length scales has prevented access to the highly nonequilibrium phase decomposition processes triggered by laser excitation. In this study, a close integration of time-resolved probing by intense femtosecond X-ray pulses with large-scale atomistic modeling has yielded unique insights into the ablation dynamics of thin gold films irradiated by femtosecond laser pulses. The emergence and growth of nanoscale density heterogeneities in the expanding ablation plume, predicted in the simulations, are mapped to the rapid evolution of distinct small angle diffraction features. This mapping enables identification of the characteristic signatures of different phase decomposition processes occurring simultaneously in the plume, which are driven by photomechanical and thermodynamic driving forces. Beyond the specific insights into the ablation phenomenon, this study demonstrates the power of joint X-ray probing and atomistic modeling of material dynamics under extreme conditions of thermal and mechanical nonequilibrium. 

Abstract The brain can be decomposed into large-scale functional networks, but the specific spatial topographies of these networks and the names used to describe them vary across studies. Such discordance has hampered interpretation and convergence of research findings across the field. We have developed theNetwork Correspondence Toolbox(NCT) to permit researchers to examine and report spatial correspondence between their novel neuroimaging results and multiple widely used functional brain atlases. We provide several exemplar demonstrations to illustrate how researchers can use the NCT to report their own findings. The NCT provides a convenient means for computing Dice coefficients with spin test permutations to determine the magnitude and statistical significance of correspondence among user-defined maps and existing atlas labels. The adoption of the NCT will make it easier for network neuroscience researchers to report their findings in a standardized manner, thus aiding reproducibility and facilitating comparisons between studies to produce interdisciplinary insights. 

Abstract Auroral substorms that move from auroral (<70°) to polar (>70°) magnetic latitudes (MLAT) are known to occur preferentially when a high‐speed solar wind stream passes by Earth. We report here on observations that occurred during a ∼75‐min interval with high‐speed solar wind on 28 November 2022 during which auroral arcs and very large geomagnetic disturbances (GMDs), also known as magnetic perturbation events (MPEs), with amplitude >9 nT/s = 540 nT/min moved progressively poleward at eight stations spanning a large region near and north of Hudson Bay, Canada shortly before midnight local time. Sustained GMD activity with amplitudes >3 nT/s appeared at each station for durations from 13 to 25 min. Spherical Elementary Currents Systems maps showed the poleward movement of a large‐scale westward electrojet as well as mesoscale electrojet structures and highly localized up/down pairs of vertical currents near these stations when the largest GMDs were observed. This study is consistent with other recent studies showing that very large poleward‐progressing GMDs can occur under high Vsw conditions, but is the first to document the sustained occurrence of large GMDs over such a wide high‐latitude region.