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PrO3 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. Pr is bonded in a 9-coordinate geometry to nine equivalent O atoms. There are three shorter (2.48 Å) and six longer (2.54 Å) Pr–O bond lengths. O is bonded in a distorted trigonal non-coplanar geometry to three equivalent Pr atoms.
PrO3Tl is (Cubic) Perovskite structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional and consists of one thallium molecule and one PrO3 framework. In the PrO3 framework, Pr3+ is bonded to six equivalent O2- atoms to form corner-sharing PrO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.32 Å) and two longer (2.33 Å) Pr–O bond lengths. O2- is bonded in a linear geometry to two equivalent Pr3+ atoms.
PrGaO3 is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional and consists of one gallium molecule and one PrO3 framework. In the PrO3 framework, Pr3+ is bonded to six equivalent O2- atoms to form corner-sharing PrO6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Pr–O bond lengths are 2.30 Å. O2- is bonded in a linear geometry to two equivalent Pr3+ atoms.
On the International Space Station (ISS), technologies capable of rapid microbial identification and disease diagnostics are not currently available. NASA still relies upon sample return for comprehensive, molecular-based sample characterization. Next-generation DNA sequencing is a powerful approach for identifying microorganisms in air, water, and surfaces onboard spacecraft. The Biomolecule Sequencer payload, manifested to SpaceX-9 and scheduled on the Increment 4748 research plan (June 2016), will assess the functionality of a commercially-available next-generation DNA sequencer in the microgravity environment of ISS. The MinION device from Oxford Nanopore Technologies (Oxford, UK) measures picoamp changes in electrical current dependent on nucleotide sequences of the DNA strand migrating through nanopores in the system. The hardware is exceptionally small (9.5 x 3.2 x 1.6 cm), lightweight (120 grams), and powered only by a USB connection. For the ISS technology demonstration, the Biomolecule Sequencer will be powered by a Microsoft Surface Pro3. Ground-prepared samples containing lambda bacteriophage, Escherichia coli, and mouse genomic DNA, will be launched and stored frozen on the ISS until experiment initiation. Immediately prior to sequencing, a crew member will collect and thaw frozen DNA samples, connect the sequencer to the Surface Pro3, inject thawed samples into a MinION flow cell, and initiate sequencing. At the completion of the sequencing run, data will be downlinked for ground analysis. Identical, synchronous ground controls will be used for data comparisons to determine sequencer functionality, run-time sequence, current dynamics, and overall accuracy. We will present our latest results from the ISS flight experiment the first time DNA has ever been sequenced in space and discuss the many potential applications of the Biomolecule Sequencer for environmental monitoring, medical diagnostics, higher fidelity and more adaptable Space Biology Human Research Program investigations, and even life detection experiments for astrobiology missions.
SAND2025-00683O Poplar is a software tool that generates a phylogenetic tree from input gene and genome sequences. It integrates established tools to identify genes within genomes, group sequences, construct gene trees, and infer a species tree. Poplar processes nucleotide sequences, identifies similar sequences using Nucleotide BLAST, groups them with DBSCAN, aligns sequences with MAFFT, constructs gene trees with RAxML-NG, and infers a species tree using ASTRAL-Pro3. This pipeline provides a structured approach to phylogenetic analysis, facilitating the study of evolutionary relationships among species. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.