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1. Cenozoic megatooth sharks occupied extremely high trophic positions

   https://doi.org/10.1126/sciadv.abl6529  

   Kast, Emma R.; Griffiths, Michael L.; Kim, Sora L.; Rao, Zixuan C.; Shimada, Kenshu; Becker, Martin A.; Maisch, Harry M.; Eagle, Robert A.; Clarke, Chelesia A.; Neumann, Allison N.; et al (June 2022, Science Advances)

   Nitrogen isotope ratios in fossil teeth place extinct megatooth sharks at the top of the marine food web. 

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2. Estimating Southern Ocean Storm Positions With Seismic Observations

   https://doi.org/10.1029/2019JC015898  

   Hell, Momme C.; Gille, Sarah T.; Cornuelle, Bruce D.; Miller, Arthur J.; Bromirski, Peter D.; Crawford, Alex D. (April 2020, Journal of Geophysical Research: Oceans)
3. Network positions in active learning environments in physics

   https://doi.org/10.1103/PhysRevPhysEducRes.16.020129  

   Traxler, Adrienne L.; Suda, Tyme; Brewe, Eric; Commeford, Kelley (October 2020, Physical Review Physics Education Research)

   null (Ed.)
4. The McdAB system positions α‐carboxysomes in proteobacteria

   https://doi.org/10.1111/mmi.14708  

   MacCready, Joshua S.; Tran, Lisa; Basalla, Joseph L.; Hakim, Pusparanee; Vecchiarelli, Anthony G. (March 2021, Molecular Microbiology)

   Abstract Carboxysomes are protein‐based organelles essential for carbon fixation in cyanobacteria and proteobacteria. Previously, we showed that the cyanobacterial nucleoid is used to equally space out β‐carboxysomes across cell lengths by a two‐component system (McdAB) in the model cyanobacteriumSynechococcus elongatusPCC 7942. More recently, we found that McdAB systems are widespread among β‐cyanobacteria, which possess β‐carboxysomes, but are absent in α‐cyanobacteria, which possess structurally and phyletically distinct α‐carboxysomes. Cyanobacterial α‐carboxysomes are thought to have arisen in proteobacteria and then horizontally transferred into cyanobacteria, which suggests that α‐carboxysomes in proteobacteria may also lack the McdAB system. Here, using the model chemoautotrophic proteobacteriumHalothiobacillus neapolitanus, we show that a McdAB system distinct from that of β‐cyanobacteria operates to position α‐carboxysomes across cell lengths. We further show that this system is widespread among α‐carboxysome‐containing proteobacteria and that cyanobacteria likely inherited an α‐carboxysome operon from a proteobacterium lacking themcdABlocus. These results demonstrate that McdAB is a cross‐phylum two‐component system necessary for positioning both α‐ and β‐carboxysomes. The findings have further implications for understanding the positioning of other protein‐based bacterial organelles involved in diverse metabolic processes. Plain language summaryCyanobacteria are well known to fix atmospheric CO₂into sugars using the enzyme Rubisco. Less appreciated are the carbon‐fixing abilities of proteobacteria with diverse metabolisms. Bacterial Rubisco is housed within organelles called carboxysomes that increase enzymatic efficiency. Here we show that proteobacterial carboxysomes are distributed in the cell by two proteins, McdA and McdB. McdA on the nucleoid interacts with McdB on carboxysomes to equidistantly space carboxysomes from one another, ensuring metabolic homeostasis and a proper inheritance of carboxysomes following cell division. This study illuminates how widespread carboxysome positioning systems are among diverse bacteria. Carboxysomes significantly contribute to global carbon fixation; therefore, understanding the spatial organization mechanism shared across the bacterial world is of great interest. 

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5. Bandgap and band edge positions in compositionally graded ZnCdO

   https://doi.org/doi.org/10.1063/1.5036710  

   I.J.T. Jensen, K.M. Johansen (January 2018, Journal of applied physics)

   Introducing Cd into ZnO allows for bandgap engineering, potentially with particularly interesting properties to observe in compositionally graded samples. In this work, compositionally graded Zn1–xCdxO samples with 0x<0.16 were made using metal organic vapour phase epitaxy. The chemical composition was studied using scanning transmission electron microscopy, while the band structure of the samples was investigated using a combination of cathodoluminescence spectroscopy and X-ray photoelectron spectroscopy (XPS). It is found that the reduction of the bandgap in our samples is caused by changes in the conduction band. The position of the Fermi level relative to the vacuum level, i.e., the workfunction, was also found to change upon addition of Cd, giving an apparent shift in the valence band when evaluated from the XPS valence spectra. 

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