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1. A carbene-stabilized diphosphorus: a triple-bonded diphosphorus (PP) and a bis(phosphinidene) (P–P) transfer agent

   https://doi.org/10.1039/D4SC05091F  

   Yoon, Joseph S; Abdellaoui, Mehdi; Gembicky, Milan; Bertrand, Guy (October 2024, Chemical Science)

   The bis-monosubstituted aminocarbene-P₂adduct is a generator of P₂, under the classical triple-bonded form (PP), but it also acts as a bis(phosphinidene) (P–P) synthetic equivalent. 

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2. KMT-2024-BLG-0404L: A triple microlensing system consisting of a star, a brown dwarf, and a planet

   https://doi.org/10.1051/0004-6361/202452760  

   Han, Cheongho; Udalski, Andrzej; Lee, Chung-Uk; Ryu, Yoon-Hyun; Albrow, Michael D; Chung, Sun-Ju; Gould, Andrew; Hwang, Kyu-Ha; Kil_Jung, Youn; Shin, In-Gu; et al (August 2025, Astronomy & Astrophysics)

   Aims. We have investigated the lensing event KMT-2024-BLG-0404. The light curve of the event exhibited a complex structure with multiple distinct features, including two prominent caustic spikes, two cusp bumps, and a brief discontinuous feature between the caustic spikes. While a binary-lens model captured the general anomaly pattern, it could not account for a discontinuous anomaly feature between the two caustic spikes. Methods. To explore the origin of the unexplained feature, we conducted more advanced modeling beyond the standard binary-lens framework. This investigation demonstrated that the previously unexplained anomaly was resolved by introducing an additional lens component with planetary mass. Results. The estimated masses of the lens components areM_p= 17.3_−8.8^+25.5M_Efor the planet, andM_h,A= 0.090_−0.046^+0.133M_⊙andM_h,B= 0.026_−0.013^+0.038M_⊙for the binary host stars. Based on these mass estimates, the lens system is identified as a planetary system where a Uranus-mass planet orbits a binary consisting of a late M dwarf and a brown dwarf. The distance to the planetary system is estimated to beD_L= 7.21_−0.97^+0.93kpc, with an 82% probability that it resides in the Galactic bulge. This discovery represents the ninth planetary system found through microlensing with a planet orbiting a binary host. Notably, it is the first case in which the host consists of both a star and a brown dwarf. 

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3. Folding points to a point and lines to a line

   Akitaya, Hugo A.; Ballinger, Brad; Demaine, Erik D.; Hull, Thomas C.; Schmidt, Christiane (August 2021, Proceedings of the 33rd Canadian Conference on Computational Geometry (CCCG 2021))

   He, Meng; Sheehy, Don (Ed.)

   We introduce basic, but heretofore generally unexplored, problems in computational origami that are similar in style to classic problems from discrete and computational geometry. We consider the problems of folding each corner of a polygon P to a point p and folding each edge of a polygon P onto a line segment L that connects two boundary points of P and compute the number of edges of the polygon containing p or L limited by crease lines and boundary edges. 

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4. When does a stream become a river?

   https://doi.org/10.1002/rra.4185  

   Czuba, Jonathan_A; Allen, George_H (July 2023, River Research and Applications)

   Abstract The distinction between a “stream” and “river” is imprecise and vague despite the popular usage of the terms across disciplines for describing flowing waterbodies. Based on an analysis of named flowing waterbodies in the continental United States, we suggest a bank‐to‐bank channel width of 15 m as a working threshold in defining smaller “streams” from larger “rivers.” 

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5. A happy accident: a novel turfgrass reference genome

   https://doi.org/10.1093/g3journal/jkad073  

   Phillips, Alyssa R.; Seetharam, Arun S.; Albert, Patrice S.; AuBuchon-Elder, Taylor; Birchler, James A.; Buckler, Edward S.; Gillespie, Lynn J.; Hufford, Matthew B.; Llaca, Victor; Romay, Maria Cinta; et al (April 2023, G3: Genes, Genomes, Genetics)

   Abstract Poa pratensis, commonly known as Kentucky bluegrass, is a popular cool-season grass species used as turf in lawns and recreation areas globally. Despite its substantial economic value, a reference genome had not previously been assembled due to the genome’s relatively large size and biological complexity that includes apomixis, polyploidy, and interspecific hybridization. We report here a fortuitous de novo assembly and annotation of a P. pratensis genome. Instead of sequencing the genome of a C4 grass, we accidentally sampled and sequenced tissue from a weedy P. pratensis whose stolon was intertwined with that of the C4 grass. The draft assembly consists of 6.09 Gbp with an N50 scaffold length of 65.1 Mbp, and a total of 118 scaffolds, generated using PacBio long reads and Bionano optical map technology. We annotated 256K gene models and found 58% of the genome to be composed of transposable elements. To demonstrate the applicability of the reference genome, we evaluated population structure and estimated genetic diversity in P. pratensis collected from three North American prairies, two in Manitoba, Canada and one in Colorado, USA. Our results support previous studies that found high genetic diversity and population structure within the species. The reference genome and annotation will be an important resource for turfgrass breeding and study of bluegrasses. 

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