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Lead-208 is the heaviest known doubly magic nucleus and its structure is therefore of special interest. Despite this magicity, which acts to provide a strong restorative force toward sphericity, it is known to exhibit both strong octupole correlations and some of the strongest quadrupole collectivity observed in doubly magic systems. In this Letter, we employ state-of-the-art experimental equipment to conclusively demonstrate, through four Coulomb-excitation measurements, the presence of a large, negative, spectroscopic quadrupole moment for both the vibrational octupole $3_1^{-}$and quadrupole $2_1^{+}$state, indicative of a preference for prolate deformation of the states. The observed quadrupole moment is discussed in the context of the expected splitting of the $3^{-}\otimes 3^{-}$two-phonon states, due to the coupling of the quadrupole and octupole motion. These results are compared with theoretical values from three different methods, which are unable to reproduce both the sign and magnitude of this deformation. Thus, in spite of its well-studied nature, ${}^{208}\mathrm{Pb}$remains a puzzle for our understanding of nuclear structure. Published by the American Physical Society2025 

As we look for traces of ancient life on Mars, we need to consider the impact of ionizing radiation in the biosignature preservation process. Here, we irradiated two organic rich terrestrial samples (Enspel and Messel shales) that have Martian analog mineralogies, with simulated cosmic rays to a dose of 0.9 MGy, equivalent of 15 million years of radiation exposure on the Martian surface. We compared a range of biosignatures before and after exposure, including total organic carbon, bulk stable carbon isotope ratios, diagnostic lipid biomarkers (hopanes and steranes), and Raman signatures akin to those collected by the Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC) instrument on Perseverance. While we did not observe a significant difference in total organic carbon, bulk stable carbon isotopes, or Raman G-band signatures, we found that five lipid biomarkers decreased by a factor of two to three in the Enspel shale. This degree of degradation exceeds current predictions by existing models or experimental studies in organic rich samples and challenges our current understanding of complex biosignatures under ionizing irradiation. 

As high school computer science course offerings have expanded over the past decade, gaps in race and gender have remained. This study embraces the “All” in the “CS for All” movement by shifting beyond access and toward abolitionist computer science teaching. Using data from professional development observations and interviews, we lift the voices of BIPOC CS teachers and bring together tenets put forth by Love (2019) for abolitionist teaching along with how these tenets map onto the work occurring in CS classrooms. Our findings indicate the importance of BIPOC teacher representation in CS classrooms and ways abolitionist teaching tenets can inform educator’s efforts at moving beyond broadening participation and toward radical inclusion, educational freedom, and self-determination, for ALL. 

The Bahama Oriole (Icterus northropi) is a Critically Endangered species restricted to Andros in The Bahamas. Previous research suggested that the Bahama Oriole nested almost exclusively in coconut palms (Cocos nucifera) in developed habitats. In 2016, however, the Bahama Oriole was documented nesting in remote pine forests for the first time. Our goals were to document where orioles nest in pine forests and to characterize nest site vegetation to determine if orioles show a preference for specific habitat characteristics. Here, we document 12 pine forest nests: six nests in understory Key thatch palms (Leucothrinax morrisii) and six nests in Caribbean pines (Pinus caribaea). For each nest tree, we measured the tree height, tree diameter, and nest height. We also took measurements of habitat characteristics in 10-m and 100-m radius plots around the nest and compared these measurements to control plots. Orioles nested in a range of pine forest habitats. However, on average, Bahama Orioles nested in pine forests with more tall thatch palms (> 2 m tall) in the understory compared to control plots. They also tended to nest in the tallest thatch palms in the understory. The findings from this study further support the importance of protecting Bahamian pine forests on Andros. 

We studied Native American college students’ perceptions of educational barriers and supports while pursuing degrees leading to careers in engineering. Based on findings from our qualitative study, we provide recommendations for students, professors, departments, and institutions on how to support Native American students to be successful as they pursue careers in science, math, and engineering careers.