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Abstract The cardiovascular system functions under continuous cyclic mechanical stretch, with disruptions in mechanical and biochemical signals contributing to disease progression. In cardiovascular disorders, these disruptions activate cardiac fibroblasts (CFs) and promote cellular senescence, yet it remains unclear whether mechanical stimuli alone can initiate this phenotype. Here, primary murine CFs are exposed to uniaxial stretch, and systematically varied mechanical parameters assessed their role in senescence induction. Loss of stretch magnitude and increase in frequency, mimicking a pathologic hypertrophy and fibrosis, led to a senescence phenotype, identified through cell cycle arrest, decreased lamin B expression, and DNA damage. Mechanically‐induced CF senescence depends on p53/p21, whereas senescence triggered by oxidative stress or lamin A/C mutation proceeded via p16. Notably, mechanically‐induced premature senescence is accompanied by reduced levels of the nuclear envelope protein emerin. These findings demonstrate that altered mechanical signals are sufficient to trigger premature senescence and implicate compromised nuclear integrity in the underlying mechanism. 

Abstract Euendolithic microorganisms, capable of bioerosion in carbonate substrates, play an important role in modern marine ecosystems and have a fossil record extending into deep time. Understanding the factors driving microboring behaviour is essential for interpreting their ecological impact and reconstructing ancient environmental conditions. In this study, we conducted field incubation experiments across multiple sites at Little Ambergris Cay in the Turks and Caicos Islands, examining microboring density in abiotic optical calcite and aragonite under varying conditions of light, subaerial exposure, current energy, substrate mineralogy and trace metal content. We observed sinuous tunnels within 1 week of incubation in transparent calcite, with longer deployment times (2.5–5 months) resulting in meaningful increases in boring density. We also documented boring activity in dark conditions, suggesting potential for enhanced mineral dissolution at night when geochemical conditions are more optimal. Trace metal analysis of our experimental substrates revealed Fe/Ca and Mn/Ca ratios exceeding western Atlantic sea water estimates by 1–3 orders, with calcites more enriched in Mn than aragonites, offering preliminary support for the novel hypothesis that dissolution of CaCO₃minerals might be a useful source of trace metals for euendoliths. Sea water chemistry varied across sites, particularly between restricted interior and open platform sites. A comparison of boring densities suggests that trace metal abundance, mineralogy, local sea water CaCO₃mineral saturation state (Ω) and subaerial exposure (e.g. intertidal vs. shallow subtidal) may all influence microboring. These findings offer new perspectives on the euendolithic lifestyle, showing how substrate selection and temporal partitioning of dissolution activity balance metabolic costs with environmental constraints. They also enhance our ability to interpret the fossil record and bioerosion dynamics under changing conditions. 

Abstract Solar Energetic Particles (SEPs) are present during increased solar activity, often associated with solar flares and coronal mass ejections (CMEs). Measuring and understanding these particles is important both for fundamental solar physics knowledge as well as the determination of radiation risks in interplanetary space. Solid‐state particle telescopes are a useful tool to measure these particles. The Relativistic Electron and Proton Telescope integrated little experiment‐2 (REPTile‐2) was a solid‐state energetic particle telescope that flew onboard the Colorado Inner Radiation Belt Experiment (CIRBE) and demonstrated a capability to measure electrons from 0.25 to 6 MeV and protons from 7 to 100 MeV with high energy and time resolution. REPTile‐2 operated in a low‐Earth orbit (LEO) and primarily measured radiation belt particles but was also able to measure SEPs during high‐latitude passes. Because of REPTile‐2's solid performance and its CubeSat‐scale size, weight, and power, an opportunity arose to fly a modified REPTile‐2, dubbed REPTile‐3, on the Emirates Mission to the Asteroid Belt (EMA). In this paper, Geometry and tracking 4 (Geant4) Monte Carlo simulations are used to motivate changes to improve REPTile‐3's ability to measure SEPs. Additionally, full instrument response functions and estimated count rates are used to understand the instrument's response to SEP fluxes. REPTile‐3 is shown to be able to measure 1.2–35 MeV protons with ΔE/E < 9%, 35–100 MeV protons with ΔE/E < 50%, 0.1–5 MeV electrons with ΔE/E < 14%, 18–131 MeV helium ions with ΔE/E < 7%, and 131–200 MeV helium ions with ΔE/E < 50% with a 102° field of view (FOV). 

Abstract This work investigates mesoscale structures in the northern high‐latitude thermosphere using an ascending‐descending accelerometry (ADA) technique to determine whether observed in‐track acceleration perturbations are influenced by in‐track winds. The ADA technique is applied to accelerometer measurements from the Challenging Minisatellite Payload mission between 2003 and 2006 during quiet geomagnetic activity, revealing a climatological view of regularly occurring acceleration perturbation structures. The ADA technique reveals a structured acceleration enhancement on the dayside with a strong signature of density dominance confined to a spatial envelope ranging from 8:00 to 17:00 magnetic local time (MLT) and between 72° and 82° magnetic latitude, aligning with past observations of the cusp density enhancement. Additionally, this sector displays a wind perturbation structure with a reversal in direction that coincides with the center of the enhancement. The premidnight quadrant shows strong evidence of wind influence in the acceleration perturbations from 18:00 to 24:00 MLT between 70° and 90° magnetic latitude associated with southward wind perturbations. This suggests that past analyses of this region could have misidentified this structure as a density enhancement by neglecting in‐track wind influences in accelerometry‐derived mass density data sets. The early morning quadrant consists of negative acceleration perturbations attributed to density depletions, with signatures of southward wind perturbations. These mass density perturbations, in conjunction with in‐track wind perturbations, suggest that the coupled ionosphere‐thermosphere mechanisms responsible for the high‐latitude density structure also influence the wind structure. This work is supplemented with TIEGCM simulations to verify the accuracy of ADA and highlight discrepancies between the simulations and observations. 

ABSTRACT As graduate students transition into advanced academic environments, the physical and social contexts in which they engage play a critical role in shaping their sense of belonging, academic success, and personal development. Using a qualitative approach, this study explores how an immersive and place‐based fieldwork program impacted community building and self‐efficacy in incoming graduate students in an Ecology and Evolutionary Biology (EEB) program. Data were collected through surveys, focus groups, and in‐depth interviews with students over the program's duration. Our findings reveal that the remote location of the program played an important role in community development and fostered autonomy and competence. We also found that choosing a discipline‐focused location for fieldwork can positively impact student experiences. Opportunities for interdisciplinary collaboration and mentorship emerged as key components of fostering a supportive academic community. The study demonstrates a positive role for place‐based strategies in graduate program design, suggesting that creating spaces that nurture collaboration, allow students to enact disciplinary skills, and present students with formative challenges can enhance academic resilience and self‐confidence. The findings offer implications for institutions looking to cultivate stronger, more cohesive graduate communities and for future research on the intersection of place, identity, and academic success in higher education. 

Liquid crystalline elastomers (LCEs) exhibit reversible macroscopic shape changes in response to a temperature change. Mechanistically, the thermomechanical response of LCEs is associated with the thermotropic nature of the liquid crystalline units (i.e., mesogens) in the polymer network. Upon heating, the mesogen‐mesogen interaction in the LCE is disrupted, which transitions the organization of the polymer network from an ordered to a disordered state. The disruption in order affects the volumetric distribution of macromolecular chains in the polymer network and results in a large directional contraction along the alignment axis. Prior reports detail that the magnitude of actuation depends strongly on the connectivity of LC mesogens (i.e., main‐chain or pendant) within the network. In this study, pendant end‐on mesogens are introduced into a primarily main‐chain supramolecular LCE composition to further reduce crosslink density while preserving overall LC concentration. The introduction of pendant end‐on mesogens to supramolecular LCE compositions further improves thermomechanical properties by enhancing strain‐temperature coupling and reducing actuation temperatures. By systematically varying the concentrations of end‐on and supramolecular mesogens, direct relationships are established between mesogen composition, polymer architecture, and the resulting thermomechanical performance of LCEs. 

ABSTRACT This review highlights how research aimed at increasing women's interest and achievement in science, technology, engineering, and math (STEM) fields is critical to U.S. national interests. STEM expertise undergirds national security and the knowledge‐based national economy. However, the U.S. faces a STEM talent crisis, with job growth projected to exceed the number of individuals with STEM expertise. Addressing the STEM labor shortage requires continuing to support those who have historically pursued STEM while also seeking to broaden who is attracted to and flourishes in STEM. Behavioral scientists have focused on understanding the importance of feeling a sense of belonging in STEM, with research showing that feeling personally accepted, respected, and included as one's authentic self in STEM facilitates success among all students. At the same time, this research has identified numerous factors that selectively decrease women's sense of belonging in STEM, creating an additional barrier among women to success in STEM. Fortunately, the identification of these barriers also reveals how to increase belonging among all students, and among women specifically. Continuing to support research on broadening participation in STEM is thus critical for the safety, prosperity, and health of all Americans. 

Abstract First characterization of year‐round Na layers from 75 to 150 km is enabled with 7 years (2011–2017) of high‐detection‐sensitivity lidar observations over Boulder (40.13°N, 105.24°W). Clear annual and semiannual oscillations (AO and SAO) are revealed in the nightly‐mean thermosphere‐ionosphere Na (TINa) (∼105–150 km) number density and volume mixing ratio with the summer maximum but spring equinox (March/April) minimum. Such stark contrast to the summer minimum in the main Na layers (∼75–105 km) supports the theory of TINa formed via TINa⁺ion neutralization (). The SAO/AO amplitude ratio profiles (75–150 km) exhibit significant changes (∼0.06–2), linking TINa SAO to thermospheric density SAO and the minimal wave/eddy transport around midlatitude equinoxes which hinders TINa⁺ion production and upward transport via reduced diffusion of the main Na layer. Stronger TINa in autumn than in spring equinox is explained by the maximal (minimal) meteoric influx occurring in September (April).