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MXenes are the fastest-growing family of two-dimensional (2D) materials. Unlike most other 2D materials, they lack bulk analogues when restacked because of their unique structure and surface terminations. They represent a new class of 2D transition-metal carbides/nitrides, not merely exfoliated van der Waals solids. They have a general formula Mn+1XnTx, where M is a transition metal, X is carbon and/or nitrogen, T represents surface terminations (O, OH, halogen, chalcogen, etc.), and n = 2—5. About 50 stoichiometric MXene compositions and dozens of solid solutions on M and X sites have already been reported. Given the infinite number of possible solid-solution compositions and combinations of surface terminations, MXenes offer an opportunity for computationally driven atomistic design of inorganic 2D structures with unique properties. MXenes exhibit electronic, optical, mechanical, and electrochemical properties that clearly distinguish them from other materials. Moreover, these properties are tunable by design and can be modulated using an ionotronic approach, leading to breakthroughs in fields ranging from optoelectronics and communication to electrochemical energy storage, catalysis, sensing, and medicine. In this talk, I’ll discuss methods for MXene synthesis and processing, the effects of MXene chemistry on their properties, and provide examples of important applications where MXenes outperform other materials. 

Long-term high-resolution orbital imaging at Mars has led to extraordinary advances in understanding martian ice and its connection to climate.  Icy seasonal phenomena such as flows in gullies, avalanches, and exotic defrosting patterns characterize the present climate. Interannual variability over a martian decade helps us deduce climatic averages and current trends. Observations of polar ice layers have characterized periodicities related to orbital change over longer timescales up to millions of years.Here, I’ll describe the HiRISE camera and its continued mission to describe a dynamic Mars over 20 years of observations, with a special focus on north polar avalanches.  HiRISE has uniquely high resolution and benefits from high signal-to-noise (even at the poles); a near-polar orbit that allows imaging of almost any location within two weeks; color bands that are sensitive to ice; and sufficient imaging stability to construct high-quality meter-scale DTMs. The scientific impact of HiRISE owes much to rapid data releases and community targeting via our online tool HiWISH, ensuring acquisition and analysis of data relevant to today’s scientific questions.  

 Sex differences in cognition are well documented, but their biological roots - especially network-level origins, remain elusive due to hormonal, environmental, and societal confounds. To isolate genetic effects, we used isogenic iPSC-derived neurons from a rare mosaic Klinefelter donor. Utilizing calcium imaging assays, we revealed a temporal divergence in maturation as XY networks show augmented connectivity patterns early on, while XX networks surpass them later on. Conversely, XY networks exhibit an increasing level of synchronization over time, while XX networks exhibit more connections. We demonstrate that such features alone accurately classify independent XX/XY networks, revealing a robust, generalizable signature.Simulating information flow revealed faster, broader spread in XY networks at later developmental stages, indicating differences in function. Modeling cognitive tasks, we found XY networks enable faster, more accurate focused problem-solving, while XX networks excel in parallel information processing. This suggests that chromosomal composition shapes cognition via inherent differences in network topology.To mechanistically unify the findings, we introduced a generative network model governed by a single parameter p (cooperativity), which controls how local synchrony is amplified into global connectivity. Varying p generated a family of networks spanning hypocooperative, optimal, and hypercooperative regimes, simultaneously moderating topology and link weights. Remarkably, empirical XX and XY networks map onto distinct regions of the cooperativity landscape, as XX networks cluster closer to an intermediate p-range, whereas XY networks exhibit higher effective cooperativity.Together, our results identify cooperativity as a unifying, quantitative biomarker linking chromosome composition to network topology and emergent cognitive function. This work reveals fundamental sex-based differences in cortical network organization and provides a principled framework for sex-aware neuroscience, with implications for personalized diagnostics and targeted interventions.