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1. Drinfeld’s Lemma for F -isocrystals, I

   https://doi.org/10.1093/imrn/rnae039  

   Kedlaya, Kiran S (March 2024, International Mathematics Research Notices)

   Abstract We prove that in either the convergent or overconvergent setting, an absolutely irreducible $$F$$-isocrystal on the absolute product of two or more smooth schemes over perfect fields of characteristic $$p$$, further equipped with actions of the partial Frobenius maps, is an external product of $$F$$-isocrystals over the multiplicands. The corresponding statement for lisse $$\overline{{\mathbb{Q}}}_{\ell }$$-sheaves, for $$\ell \neq p$$ a prime, is a consequence of Drinfeld’s lemma on the fundamental groups of absolute products of schemes in characteristic $$p$$. The latter plays a key role in V. Lafforgue’s approach to the Langlands correspondence for reductive groups with $$\ell $$-adic coefficients; the $$p$$-adic analogue will be considered in subsequent work with Daxin Xu. 

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2. CRISPR‐Cas9 Genome Editing in the Moss Physcomitrium (Formerly Physcomitrella ) patens

   https://doi.org/10.1002/cpz1.725  

   Wu, Shu‐Zon; Ryken, Samantha E.; Bezanilla, Magdalena (April 2023, Current Protocols)

   Abstract Until recently, precise genome editing has been limited to a few organisms. The ability of Cas9 to generate double stranded DNA breaks at specific genomic sites has greatly expanded molecular toolkits in many organisms and cell types. Before CRISPR‐Cas9 mediated genome editing,P. patenswas unique among plants in its ability to integrate DNA via homologous recombination. However, selection for homologous recombination events was required to obtain edited plants, limiting the types of editing that were possible. Now with CRISPR‐Cas9, molecular manipulations inP. patenshave greatly expanded. This protocol describes a method to generate a variety of different genome edits. The protocol describes a streamlined method to generate the Cas9/sgRNA expression constructs, design homology templates, transform, and quickly genotype plants. © 2023 Wiley Periodicals LLC. Basic Protocol 1: Constructing the Cas9/sgRNA transient expression vector Alternate Protocol 1: Shortcut to generating single and pooled Cas9/sgRNA expression vectors Basic Protocol 2: Designing the oligonucleotide‐based homology‐directed repair (HDR) template Alternate Protocol 2: Designing the plasmid‐based HDR template Basic Protocol 3: Inducing genome editing by transforming CRISPR vector intoP. patensprotoplasts Basic Protocol 4: Identifying edited plants. 

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3. The social amoeba Dictyostelium discoideum rescues Paraburkholderia hayleyella , but not P. agricolaris , from interspecific competition

   https://doi.org/10.1093/femsec/fiad055  

   Medina, James_M; Queller, David_C; Strassmann, Joan_E; Garcia, Justine_R (May 2023, FEMS Microbiology Ecology)

   Abstract Bacterial endosymbionts can provide benefits for their eukaryotic hosts, but it is often unclear if endosymbionts benefit from these relationships. The social amoeba Dictyostelium discoideum associates with three species of Paraburkholderia endosymbionts, including P. agricolaris and P. hayleyella. These endosymbionts can be costly to the host but are beneficial in certain contexts because they allow D. discoideum to carry prey bacteria through the dispersal stage. In experiments where no other species are present, P. hayleyella benefits from D. discoideum while P. agricolaris does not. However, the presence of other species may influence this symbiosis. We tested if P. agricolaris and P. hayleyella benefit from D. discoideum in the context of resource competition with Klebsiella pneumoniae, the typical laboratory prey of D. discoideum. Without D. discoideum, K. pneumoniae depressed the growth of both Paraburkholderia symbionts, consistent with competition. P. hayleyella was more harmed by interspecific competition than P. agricolaris. We found that P. hayleyella was rescued from competition by D. discoideum, while P. agricolaris was not. This may be because P. hayleyella is more specialized as an endosymbiont; it has a highly reduced genome compared to P. agricolaris and may have lost genes relevant for resource competition outside of its host. 

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4. a -axis YBa2Cu3O7− x /PrBa2Cu3O7− x /YBa2Cu3O7− x trilayers with subnanometer rms roughness

   https://doi.org/10.1063/5.0034648  

   Suyolcu, Y_Eren; Sun, Jiaxin; Goodge, Berit_H; Park, Jisung; Schubert, Jürgen; Kourkoutis, Lena_F; Schlom, Darrell_G (February 2021, APL Materials)

   We demonstrate a-axis YBa2Cu3O7−x/PrBa2Cu3O7−x/YBa2Cu3O7−x trilayers grown on (100) LaAlO3 substrates with improved interface smoothness. The trilayers are synthesized by ozone-assisted molecular-beam epitaxy. The thickness of the PrBa2Cu3O7−x layer is held constant at 8 nm, and the thickness of the YBa2Cu3O7−x layers is varied from 24 nm to 100 nm. X-ray diffraction measurements show all trilayers to have >97% a-axis content. The rms roughness of the thinnest trilayer is <0.7 nm, and this roughness increases with the thickness of the YBa2Cu3O7−x layers. The thickness of the YBa2Cu3O7−x layers also affects the transport properties: while all samples exhibit an onset of the superconducting transition at and above 85 K, the thinner samples show wider transition widths, ΔTc. High-resolution scanning transmission electron microscopy reveals coherent and chemically sharp interfaces and that growth begins with a cubic (Y,Ba)CuO3−x perovskite phase that transforms into a-axis oriented YBa2Cu3O7−x as the substrate temperature is ramped up. 

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5. Temperature-dependent dielectric behavior of A 6 B 2O17 ( A  = Zr, Hf; B  = Nb, Ta) phases

   https://doi.org/10.1063/5.0219964  

   Spurling, R Jackson; Marakovits, Michael T; Hossain, Arafat; Almishal, Saeed_S I; Perini, Steven E; Lanagan, Michael T; Maria, Jon-Paul (August 2024, Applied Physics Letters)

   We report on temperature-dependent dielectric behavior of disordered ternary A6B2O17 (A = Zr, Hf; B = Nb, Ta)-form oxides in the GHz frequency range. The microwave dielectric properties including relative permittivity, dielectric loss, and temperature-dependent relative permittivity were characterized using cylindrical dielectric resonators using a resonant post measurement technique. Dielectric measurements through the resonant post method approach generally agree with dielectric measurements of A6B2O17 bulk ceramics measured through standard resonant post techniques. Coefficients describing the temperature-dependent relative permittivity for ternary A6B2O17 phases are strongly positive, suggesting contributions to polarizability arising from long-range mechanisms potentially associated with structural disorder. These observations support the working hypothesis that material functionality can be engineered by the chemical diversity and structural disorder possible in high configurational entropy A6B2O17 phases. 

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