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1. The eigensplitting of the fiber of the cyclotomic trace for the sphere spectrum

   https://doi.org/10.1090/tran/8822  

   Blumberg, Andrew; Mandell, Michael (January 2022, Transactions of the American Mathematical Society)

   Let p ∈ Z p\in {\mathbb {Z}} be an odd prime. We show that the fiber sequence for the cyclotomic trace of the sphere spectrum S {\mathbb {S}} admits an “eigensplitting” that generalizes known splittings on K K -theory and T C TC . We identify the summands in the fiber as the covers of Z p {\mathbb {Z}}_{p} -Anderson duals of summands in the K ( 1 ) K(1) -localized algebraic K K -theory of Z {\mathbb {Z}} . Analogous results hold for the ring Z {\mathbb {Z}} where we prove that the K ( 1 ) K(1) -localized fiber sequence is self-dual for Z p {\mathbb {Z}}_{p} -Anderson duality, with the duality permuting the summands by i ↦ p − i i\mapsto p-i (indexed mod p − 1 p-1 ). We explain an intrinsic characterization of the summand we call Z Z in the splitting T C ( Z ) p ∧ ≃ j ∨ Σ j ′ ∨ Z TC({\mathbb {Z}})^{\wedge }_{p}\simeq j \vee \Sigma j’\vee Z in terms of units in the p p -cyclotomic tower of Q p {\mathbb {Q}}_{p} . 

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2. The Origin of Universality in the Inner Edges of Planetary Systems

   https://doi.org/10.3847/2041-8213/acdb5d  

   Batygin, Konstantin; Adams, Fred C.; Becker, Juliette (July 2023, The Astrophysical Journal Letters)

   Abstract The characteristic orbital period of the innermost objects within the galactic census of planetary and satellite systems appears to be nearly universal, withPon the order of a few days. This paper presents a theoretical framework that provides a simple explanation for this phenomenon. By considering the interplay between disk accretion, magnetic field generation by convective dynamos, and Kelvin–Helmholtz contraction, we derive an expression for the magnetospheric truncation radius in astrophysical disks and find that the corresponding orbital frequency is independent of the mass of the host body. Our analysis demonstrates that this characteristic frequency corresponds to a period ofP∼ 3 days although intrinsic variations in system parameters are expected to introduce a factor of a ∼2–3 spread in this result. Standard theory of orbital migration further suggests that planets should stabilize at an orbital period that exceeds disk truncation by a small margin. Cumulatively, our findings predict that the periods of close-in bodies should spanP∼ 2–12 days—a range that is consistent with observations. 

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3. The dynamics and changes of the world’s monsoons

   https://doi.org/10.1063/PT.3.5308  

   Biasutti, Michela; Ting, Mingfang; Hill, Spencer A. (September 2023, Physics Today)

   The seasonal rainy phase observed in many places across Earth is shaping the climate and is being changed by global climate trends. 

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4. Program of the 87th Annual Meeting of the American Association of Physical Anthropologists

   https://doi.org/10.1002/ajpa.23489  

   DeCasien, A.R. (April 2018, American Journal of Physical Anthropology)

   Across taxa, sexually selected traits are more variable in the target sex than 1) the same trait in the opposite sex or 2) non-sexually selected traits, likely due to their condition-dependent expression. In humans, males show greater variability in certain cognitive abilities and brain structures that 1) may facilitate intra- or intersexual competition and 2) are greater/larger in males on average, suggesting these traits may also have been subject to sexual selection. This study investigates sex differences in brain structure variability in chimpanzees. Although male chimpanzees exhibit strong intrasexual competition, reproductive skew is reduced by female mate choice and male coercion. In vivo MRI scans were collected from 226 (135F/91M) individuals and surface areas were calculated for 25 cortical sulci. Outliers for each sex and sulcus were removed prior to analysis. We measured sex differences in variability by calculating the ratio of male-to-female standard deviations of MCMCglmm residuals, controlling for age, rearing condition, scanner type, and kinship. We tested for significant sex differences through permutation. We find that males are significantly more variable at the cingulate (ratio=1.18;p=0.043), middle-frontal (ratio=1.36;p=0.001), occipital-lateral (ratio=1.20;p=0.029), occipital- temporal-marginal (ratio=1.8;p=0.006), superior-temporal (ratio=1.36;p<0.001), subcentral-posterior (ratio=1.62;p=0.033), and superior-parietal (ratio=1.21;p=0.028) sulci. These regions are associated with social perception, face recognition, and motion prediction. Females are more variable at the medio-parietal-occipital sulcus (ratio=0.78;p=0.009), a region associated with planning. This is the first study to demonstrate greater male variability in brain structure in a nonhuman primate species, and suggests sexual selection may lead to greater variability in male cognition across taxa. 

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5. Reassignment of the Structure of Setosol

   https://doi.org/10.1002/ejoc.202400431  

   Bates, Roderick_W; Elyashberg, Mikhail; Kutateladze, Andrei_G; Williams, Craig_M (October 2024, European Journal of Organic Chemistry)

   Abstract By a combination of computational methods and comparison of spectroscopic data, the benzooxonin structure proposed for setosol is shown to be incorrect. The correct structure is that of a known biaryl ether natural product. 

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