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1. Scale-free behavioral dynamics directly linked with scale-free cortical dynamics

   https://doi.org/10.7554/eLife.79950  

   Jones, Sabrina A; Barfield, Jacob H; Norman, V Kindler; Shew, Woodrow L (January 2023, eLife)

   Naturally occurring body movements and collective neural activity both exhibit complex dynamics, often with scale-free, fractal spatiotemporal structure. Scale-free dynamics of both brain and behavior are important because each is associated with functional benefits to the organism. Despite their similarities, scale-free brain activity and scale-free behavior have been studied separately, without a unified explanation. Here, we show that scale-free dynamics of mouse behavior and neurons in the visual cortex are strongly related. Surprisingly, the scale-free neural activity is limited to specific subsets of neurons, and these scale-free subsets exhibit stochastic winner-take-all competition with other neural subsets. This observation is inconsistent with prevailing theories of scale-free dynamics in neural systems, which stem from the criticality hypothesis. We develop a computational model which incorporates known cell-type-specific circuit structure, explaining our findings with a new type of critical dynamics. Our results establish neural underpinnings of scale-free behavior and clear behavioral relevance of scale-free neural activity. 

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2. Rigid Supramolecular Aramid Nanotubes as Catalyst Supports

   https://doi.org/10.1002/adma.202510143  

   Cho, Yukio; Tai, Kiera Y; Lamour, Guillaume; Christoff‐Tempesta, Ty; Sinha, Debaditya Bose; Choi, Yu‐Jin; Meacham, Rebecca; Rota, Dechen T; Wu, Siyu; Zuo, Xiaobing; et al (January 2026, Advanced Materials)

   Abstract Solution‐phase heterogeneous catalysts benefit from nanoscale dimensions, which maximize specific surface area and enhance catalytic activity. However, the ease of recovering such nanocatalysts depends on the design of the support materials, which are often particle‐like. Rigid 1D nanomaterials are proposed as supports that can enhance separability while offering high volumetric specific surface area for greater catalyst loading and activity. Here, aramid amphiphiles (AAs) are designed to spontaneously self‐assemble in water into high‐aspect‐ratio supramolecular nanotubes with tunable surface chemistry. These AA nanotubes exhibit high persistence lengths (P= 750 ± 340 µm) and mechanical stiffnesses (3 N/m). Incorporating surface thiol groups enables immobilization of catalytic gold nanoparticles. The resulting AA nanotube‐gold nanoparticle complexes exhibit high catalytic activity, efficient recoverability via simple microfiltration, and sustained reusability over ten reaction cycles. This study demonstrates the utility of molecular self‐assembled 1D nanomaterials as versatile scaffolds for the reuse and recovery of nanoscale catalysts. 

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3. Deletion of the testosterone-sensitive TRPM8 Ca++ channel disrupts measures of anxiety and depression in mice: Implications for dopamine

   Shepler, B; Erdmier, A; Palmisano, H; Asuthkar, S; Koeltzow, TE (April 2024, Bradley University)

   Testosterone exerts high affinity for the Transient Receptor Potential Melastatin 8 (TRPM8) Ca2+ channel. TRPM8 -/- male mice exhibit disrupted sexual behavior (e.g., indiscriminate approach, delayed satiety), possibly due to decreased ventral tegmental area dopamine neuron activity. It is hypothesized that TRPM8 null mutant mice (Jackson Laboratories) will exhibit disruptions across a range of motivationally-relevant behaviors, including spontaneous locomotor activation, detection of novel stimuli, sucrose preference, and sensitivity to the psychomotor stimulant amphetamine. Initial findings indicate that male TRPM8 mutant mice (n=6) exhibit decreased nocturnal locomotor activity (F(1,12)=23.41, p<0.001), increased behavioral anxiety in the light/dark task (t(10)=2.44, p<0.05; d=1.4), and behavioral despair in the forced swim task (t(10)=3.70, p<0.005; d=2.1). In contrast, these mice tended to prefer a low concentration (0.1%) of sucrose compared to wildtype males (n=6; t(10)=1.35, p=0.09; d=0.83). Tests for sensitivity to amphetamine are in progress. These data suggest a pivotal role for TRPM8 in motivated behavior. 

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4. Moderate-separation Binary Companions May Influence Young Stellar X-Ray Luminosity

   https://doi.org/10.3847/2515-5172/ada14e  

   Clark, M; Sullivan, Kendall; Soares-Furtado, Melinda (December 2024, Research Notes of the AAS)

   Abstract Young pre-main sequence stars exhibit elevated X-ray levels due to their strong magnetic activity. Understanding young stars’ X-ray activity is essential for contextualizing the forming planets that they host. Binary stars present a unique environment that may influence planet formation and evolution. In this work, we assembled a sample of 65 systems with stellar characterization from the literature and X-ray fluxes from the XMM-Newton Extended Survey of the Taurus Molecular Cloud to investigate the potential relationship between binary separation and X-ray flux. We found that binary stars with separations smaller than the sample median may exhibit elevated X-ray flux compared to single stars. This suggests that binary companions could influence stellar and planetary evolution and warrants further investigation. 

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5. Hippocampus-dependent emergence of spatial sequence coding in retrosplenial cortex

   https://doi.org/10.1073/pnas.1803224115  

   Mao, Dun; Neumann, Adam R.; Sun, Jianjun; Bonin, Vincent; Mohajerani, Majid H.; McNaughton, Bruce L. (July 2018, Proceedings of the National Academy of Sciences)

   Retrosplenial cortex (RSC) is involved in visuospatial integration and spatial learning, and RSC neurons exhibit discrete, place cell-like sequential activity that resembles the population code of space in hippocampus. To investigate the origins and population dynamics of this activity, we combined longitudinal cellular calcium imaging of dysgranular RSC neurons in mice with excitotoxic hippocampal lesions. We tracked the emergence and stability of RSC spatial activity over consecutive imaging sessions. Overall, spatial activity in RSC was experience-dependent, emerging gradually over time, but, as seen in the hippocampus, the spatial code changed dynamically across days. Bilateral but not unilateral hippocampal lesions impeded the development of spatial activity in RSC. Thus, the emergence of spatial activity in RSC, a major recipient of hippocampal information, depends critically on an intact hippocampus; the indirect connections between the dysgranular RSC and the hippocampus further indicate that hippocampus may exert such influences polysynapticallywithin neocortex. 

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