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1. The Astrophysical Thoughts of Carl Friedrich von Weizsäcker

   https://doi.org/10.1007/s00016-025-00325-0  

   Wiescher, Michael; Langanke, Karlheinz (April 2025, Physics in Perspective)

   Abstract Carl Friedrich von Weizsäcker published two important papers on topics of nuclear astrophysics in 1937 and 1938 before he turned his attention elsewhere motivated by the discovery of fission and the outbreak of war in 1939. It seems, however, that he continued to actively think about issues related to astrophysics, namely the discussion and role of neutron stars and cosmology. Both are contemporary topics today. This paper presents the development of Weizsäcker’s thoughts in the years between 1935 and 1945, making use of his personal notes and letters. 

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2. Accidental synthesis of a previously unknown quasicrystal in the first atomic bomb test

   https://doi.org/10.1073/pnas.2101350118  

   Bindi, Luca; Kolb, William; Eby, G. Nelson; Asimow, Paul D.; Wallace, Terry C.; Steinhardt, Paul J. (May 2021, Proceedings of the National Academy of Sciences)

   The first test explosion of a nuclear bomb, the Trinity test of 16 July 1945, resulted in the fusion of surrounding sand, the test tower, and copper transmission lines into a glassy material known as “trinitite.” Here, we report the discovery, in a sample of red trinitite, of a hitherto unknown composition of icosahedral quasicrystal, Si₆₁Cu₃₀Ca₇Fe₂. It represents the oldest extant anthropogenic quasicrystal currently known, with the distinctive property that its precise time of creation is indelibly etched in history. Like the naturally formed quasicrystals found in the Khatyrka meteorite and experimental shock syntheses of quasicrystals, the anthropogenic quasicrystals in red trinitite demonstrate that transient extreme pressure–temperature conditions are suitable for the synthesis of quasicrystals and for the discovery of new quasicrystal-forming systems. 

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3. The dipolar field of rotating bodies in two dimensions

   https://doi.org/10.1017/S0022112008001857  

   SMITH, STEFAN G.; MICHELIN, SÉBASTIEN; CROWDY, D. G. (July 2008, Journal of Fluid Mechanics)

   null (Ed.)

   The fluid velocity far from a translating body in two-dimensional irrotational flow is generally dipolar. This is a classical result. Here we ask when the dipolar component vanishes. Lamb (1945, § 126) provides symmetry conditions on the virtual mass tensor for this to be the case. We show that these conditions are not necessary and obtain the sufficient and necessary condition in terms of the shape of the body using conformal maps. Some explicit examples are constructed based on this condition. 

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4. On the genus Neoscotolemon (Opiliones: Laniatores: Samooidea incertae sedis) with the description of one new species

   https://doi.org/10.11646/zootaxa.5563.1.11  

   PÉREZ-GONZÁLEZ, ABEL; MAMANI, VANESA; PROUD, DANIEL N (January 2025, Zootaxa)

   The genus Neoscotolemon Roewer, 1912, is herein reviewed and re-diagnosed for the first time using modern taxonomic standards. Neoscotolemon is removed from Grassatores incertae sedis and transferred to the superfamily Samooidea incertae sedis, transl. nov. The genera Citranus Goodnight & Goodnight, 1942, Rula Goodnight & Goodnight, 1942, and Vlachiolus Šilhavý, 1979, are considered new subjective synonyms of Neoscotolemon Roewer, 1912. Neoscotolemon pictipes (Banks, 1908) is redescribed and fully illustrated, including, for the first time, the external and genital morphology of males. Neoscotolemon armasi spec. nov. is described from Isla de la Juventud, Cuba. Five additional species are transferred to Neoscotolemon, including some that were newly ranked from subspecies to species: Neoscotolemon bolivari (Goodnight & Goodnight, 1945) comb. nov., stat. rest. (transferred from Stygnomma), N. cotilla (Goodnight & Goodnight, 1945) comb. nov., nom. rest., stat. rest. (transferred from Stygnomma), N. spinifer (Packard, 1888) comb. rest. (transferred from Stygnomma), N. tancahensis (Goodnight & Goodnight, 1951) comb. nov., stat. prom. (transferred from Stygnomma), and N. vojtechi (Šilhavý, 1979) comb. nov. (transferred from Vlachiolus). Finally, upon reexamination of Neoscotolemon lutzi Goodnight & Goodnight, 1942, the male genital morphology, herein illustrated for the first time, indicates that this species is not related to Neoscotolemon and is therefore transferred to Metapellobunus and combined as Metapellobunus lutzi (Goodnight & Goodnight, 1942) comb. nov. A map is provided showing the known distribution of Neoscotolemon in the southeastern USA, Cuba, Mexico, and Belize with doubtful and unconfirmed records in Jamaica and Cayman Islands. Neoscotolemon is characterized by multiple somatic and genitalic traits. Atop the hourglass-shaped scutum magnum, there is a widely-separated pair of eyes with a large spiniform apophysis placed between them. The pedipalps are robust, and in major males they are elongated and thickened. In major and minor males, the metatarsus III is enlarged, ventrally covered with modified trichomes, and possesses aggregated pores distally. The penis has a ventral plate ending in a deep calyx, armed with two bilateral rows of macrosetae, and a short, pointed stylus that is basally fused to two laminar conductors. Although the family allocation remains uncertain, the re-diagnosis of Neoscotolemon, together with the re-description of the type species, makes this an easily recognizable genus, among Samooidea, that now contains seven species.  

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5. Cambrian trilobites and associated fossils from the Uinta Mountains of Utah (USA)

   https://doi.org/10.1017/jpa.2023.82  

   Foster, John R; Sundberg, Frederick A; Hagadorn, James W (January 2024, Journal of Paleontology)

   Abstract Fossils are rare in Cambrian strata of the Uinta Mountains of northeastern Utah, and are important because they can help integrate our understanding of laterally adjacent but discontiguous rock units, e. g., the Tintic Quartzite of Utah and the Lodore Formation of Utah-Colorado. New body fossils from strata previously mapped as Tintic or Cambrian Undifferentiated, but here interpreted as the Ophir Formation, include indeterminate hyoliths and hyolithids, brachiopods including a linguloid, and the trilobitesTrachycheilusResser, 1945 andElrathiellaPoulsen, 1927. The last two assign these strata to theEhmaniellaBiozone (uppermost Wuliuan Stage; Miaolingian Series) or traditional Laurentian middle Cambrian. These data, together with fossil occurrences elsewhere in Utah, require that the Tintic Quartzite was deposited prior to and/or during the early Wuliuan, and suggest that the unit could be correlative to much of the Lodore Formation of Utah and Colorado. 

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