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1. A Reference Genome Assembly of American Bison, Bison bison bison

   https://doi.org/10.1093/jhered/esab003  

   Oppenheimer, Jonas; Rosen, Benjamin D; Heaton, Michael P; Vander Ley, Brian L; Shafer, Wade R; Schuetze, Fred T; Stroud, Brad; Kuehn, Larry A; McClure, Jennifer C; Barfield, Jennifer P; et al (February 2021, Journal of Heredity)

   Koepfli, Klaus-Peter (Ed.)

   Abstract Bison are an icon of the American West and an ecologically, commercially, and culturally important species. Despite numbering in the hundreds of thousands today, conservation concerns remain for the species, including the impact on genetic diversity of a severe bottleneck around the turn of the 20th century and genetic introgression from domestic cattle. Genetic diversity and admixture are best evaluated at genome-wide scale, for which a high-quality reference is necessary. Here, we use trio binning of long reads from a bison–Simmental cattle (Bos taurus taurus) male F1 hybrid to sequence and assemble the genome of the American plains bison (Bison bison bison). The male haplotype genome is chromosome-scale, with a total length of 2.65 Gb across 775 scaffolds (839 contigs) and a scaffold N50 of 87.8 Mb. Our bison genome is ~13× more contiguous overall and ~3400× more contiguous at the contig level than the current bison reference genome. The bison genome sequence presented here (ARS-UCSC_bison1.0) will enable new research into the evolutionary history of this iconic megafauna species and provide a new tool for the management of bison populations in federal and commercial herds. 

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2. Native megafauna ( Bison bison ) act as a surprising inhibitor of cedar tree expansion in a Great Plains grassland

   https://doi.org/10.1002/eap.70108  

   Noble, Sidney; Ratajczak, Zak; Noble, Brynn (October 2025, Ecological Applications)

   Abstract In the Central Great Plains of North America, fire suppression is causing transitions from grasslands to shrublands and woodlands. This woody encroachment alters plant community composition, decreases grassland biodiversity, undermines key ecosystem services, and is difficult to reverse. How native grazers affect woody encroachment is largely unknown, especially compared to domesticated grazers. Bison were once the most widespread megafauna in North America and are typically categorized as grazers, with negative effects on grasses that indirectly benefit woody plants. However, bison can negatively impact woody plants through occasional browsing and mechanical disturbance. This study reports on a 30‐year experiment at Konza Prairie Biological Station, a mesic grassland in the Central Great Plains of North America, under fire suppression and experimental presence/absence of bison. Based on remote sensing, deciduous tree canopy cover was lower with bison (6% grazed vs. 16% ungrazed). Shrub land cover showed no difference (42% grazed vs. 41% ungrazed), while herbaceous land cover was higher with bison (51% grazed vs. 40% ungrazed). Evergreen tree canopy cover (Juniperus virginianaL.), which decreases biodiversity and increases wildfire risk, was approximately 0% with bison compared to 4% without bison. In the survival trial ofJ. virginianaseedlings, we found a 40% overwinter mortality with bison, compared to 5% mortality without bison. Compared to ungrazed areas, native plant species richness was 97% and 38% higher in bison‐grazed uplands and lowlands, respectively. Species evenness and Shannon's index were higher in the bison treatment in uplands, but not in lowlands. Bison affected community composition, resulting in higher cover of short grass species and lower tree cover. While grazers are generally assumed to favor woody plants, we found that bison had the opposite effect at low fire frequencies. We argue that the large size of bison and their behaviors account for this pattern, including trampling, horning, and occasional browsing. From a conservation perspective, bison might hamper tree expansion and increase plant diversity in tallgrass prairies and similar grasslands. 

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3. SAXS structure of homodimeric oxyHemoglobin III from bivalve Lucina pectinata

   https://doi.org/10.1002/bip.23427  

   Marchany‐Rivera, Darya; Estremera‐Andújar, Rafael A.; Nieves‐Marrero, Carlos; Ruiz‐Martínez, Carlos R.; Bauer, William; López‐Garriga, Juan (April 2021, Biopolymers)

   Abstract Hemoglobin III (HbIII) is one of the two oxygen reactive hemoproteins present in the bivalve,Lucina pectinata. The clam inhabits a sulfur‐rich environment and HbIII is the only hemoprotein present in the system which does not yet have a structure described elsewhere. It is known that HbIII exists as a heterodimer with hemoglobin II (HbII) to generate the stable Oxy(HbII‐HbIII) complex but it remains unknown if HbIII can form a homodimeric species. Here, a new chromatographic methodology to separate OxyHbIII from the HbII‐HbIII dimer has been developed, employing a fast performance liquid chromatography and ionic exchange chromatography column. The nature of OxyHbIII in solution at concentrations from 1.6 mg/mL to 20.4 mg/mL was studied using small angle X‐ray scattering (SAXS). The results show that at all concentrations, the Oxy(HbIII‐HbIII) dimer dominates in solution. However, as the concentration increases to nonphysiological values, 20.4 mg/mL, HbIII forms a 30% tetrameric fraction. Thus, there is a direct relationship between the Oxy(HbIII‐HbIII) oligomeric form and hemoglobin concentration. We suggest it is likely that the OxyHbIII dimer contributes to active oxygen transport in tissues ofL pectinata, where the Oxy(HbII‐HbIII) complex is not present. 

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4. FgPal1 regulates morphogenesis and pathogenesis in Fusarium graminearum

   https://doi.org/10.1111/1462-2920.15266  

   Yin, Jinrong; Hao, Chaofeng; Niu, Gang; Wang, Wei; Wang, Guanghui; Xiang, Ping; Xu, Jin‐Rong; Zhang, Xue (December 2020, Environmental Microbiology)

   null (Ed.)
5. Structural stability and the low‐lying singlet and triplet states of BN ‐ n ‐acenes, n  = 1–7

   https://doi.org/10.1002/jcc.27038  

   Milanez, Bruno D.; dos Santos, Gustavo M.; Pinheiro, Jr, Max; Ueno, Leonardo T.; Ferrão, Luiz F. A.; Aquino, Adelia J. A.; Lischka, Hans; Machado, Francisco B. C. (November 2022, Journal of Computational Chemistry)

   Abstract The chemical stability and the low‐lying singlet and triplet excited states of BN‐n‐acenes (n = 1–7) were studied using single reference and multireference methodologies. From the calculations, descriptors such as the singlet‐triplet splitting, the natural orbital (NO) occupations and aromaticity indexes are used to provide structural and energetic analysis. The boron and nitrogen atoms form an isoelectronic pair of two carbon atoms, which was used for the complete substitution of these units in the acene series. The structural analysis confirms the effects originated from the insertion of a uniform pattern of electronegativity difference within the molecular systems. The covalent bonds tend to be strongly polarized which does not happen in the case of a carbon‐only framework. This effect leads to a charge transfer between neighbor atoms resulting in a more strengthened structure, keeping the aromaticity roughly constant along the chain. The singlet‐triplet splitting also agrees with this stability trend, maintaining a consistent gap value for all molecules. The BN‐n‐acenes molecules possess a ground state with monoconfigurational character indicating their electronic stability. The low‐lying singlet excited states have charge transfer character, which proceeds from nitrogen to boron. 

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