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Item Cultivation and visualization of a methanogen of the phylum Thermoproteota(Springer Science and Business Media LLC, 2024-07) Kohtz, Anthony J.; Petrosian, Nikolai; Krukenberg, Viola; Jay, Zackary J.; Pihofer, Martin; Hatzenpichler, RolandMethane is the second most abundant climate-active gas, and understanding its sources and sinks is an important endeavour in microbiology, biogeochemistry, and climate sciences1,2. For decades, it was thought that methanogenesis, the ability to conserve energy coupled to methane production, was taxonomically restricted to a metabolically specialized group of archaea, the Euryarchaeota1. The discovery of marker genes for anaerobic alkane cycling in metagenome-assembled genomes obtained from diverse habitats has led to the hypothesis that archaeal lineages outside the Euryarchaeota are also involved in methanogenesis3,4,5,6. Here we cultured Candidatus Methanosuratincola verstraetei strain LCB70, a member of the archaeal class Methanomethylicia (formerly Verstraetearchaeota) within the phylum Thermoproteota, from a terrestrial hot spring. Growth experiments combined with activity assays, stable isotope tracing, and genomic and transcriptomic analyses demonstrated that this thermophilic archaeon grows by means of methyl-reducing hydrogenotrophic methanogenesis. Cryo-electron tomography revealed that Ca. M. verstraetei are coccoid cells with archaella and chemoreceptor arrays, and that they can form intercellular bridges connecting two to three cells with continuous cytoplasm and S-layer. The wide environmental distribution of Ca. M. verstraetei suggests that they might play important and hitherto overlooked roles in carbon cycling within diverse anoxic habitats.Item Exploring canyons beneath Devon Ice Cap for sub-glacial drainage using radar and thermodynamic modeling(Cambridge University Press, 2024-09) Pierce, Chris; Skidmore, Mark; Beem, Lucas; Blankenship, Don; Adams, Ed; Gerekos, ChristopherSub-glacial canyon features up to 580 m deep between flat terraces were identified beneath Devon Ice Cap during a 2023 radar echo sounding (RES) survey. The largest canyon connects a hypothesized brine network near the Devon Ice Cap summit with the marine-terminating Sverdrup outlet glacier. This canyon represents a probable drainage route for the hypothesized water system. Radar bed reflectivity is consistently 30 dB lower along the canyon floor than on the terraces, contradicting the signature expected for sub-glacial water. We compare these data with backscattering simulations to demonstrate that the reflectivity pattern may be topographically induced. Our simulated results indicated a 10 m wide canal-like water feature is unlikely along the canyon floor, but smaller features may be difficult to detect via RES. We calculated basal temperature profiles using a 2D finite difference method and found the floor may be up to 18°C warmer than the terraces. However, temperatures remain below the pressure melting point, and there is limited evidence that the canyon floor supports a connected drainage system between the DIC summit and Sverdrup Glacier. The terrain beneath Devon Ice Cap demonstrates limitations for RES. Future studies should evaluate additional correction methods near complex terrain, such as RES simulation as we demonstrate here.Item The Role of Teacher Education in Improving Digital Literacy: A Pre-Service Teacher Case Study(New Prairie Press, 2024-10) Taheri, Rana; Pennington, SarahTechnology is crucial for teaching and learning in the 21st century. However, many pre-service teachers (PSTs) feel unprepared to utilize digital literacy (DL) in their future classes. This study explored PST’s perceptions of their DL knowledge and the perceived impact of their teacher education programs through a qualitative bounded case study method. Participants for this study were three PSTs engaged in a technology integration course at a land grant university in the northwestern US. Participants engaged in recorded one-on-one semi-structured interviews to learn about their perceptions and readiness for DL. The findings indicate that while PSTs were aware of DL, they lacked confidence in their ability to teach it. The study identified four critical themes related to the PSTs' perspectives on DL: concerns, challenges, advantages, and future decisions. The prioritization of DL training in teacher education programs and the reconsideration of engaging technology-related courses by universities and policymakers are recommended.Item Cost, Advocacy, and a Mechanism for Transformation: The Proposed Power of Open Access Funds(American Library Association, 2024-01) Sterman, Leila BelleAs paid open access becomes a mainstream academic practice, stakeholders must evaluate their role in the system. While open access advocates develop new ways to support the publication process and funding structure, commercial publishers continue to pivot to maintain their profit, relevance, and power in the publication system. This article provides the details of Montana State University’s Open Access Author Fund as an evaluation of the service and its impact on the local publishing ecosystem. As stewards of publicly funded knowledge, it is essential to critically analyze each new publishing route before adopting and supporting it. Especially when models claim to transform the system, librarians need to understand how an action changes the system, for whom, and at what cost.Item Short Communication: artificially reared ewes cannot be distinguished from natural reared ewes based on observed maternal behavior or lamb weaning weights(Oxford University Press, 2024-09) Posbergh, Christian J.; Miles, Asha M.; Pettifor, Natasha L.; Thonney, Michael L.Artificially rearing lambs is an important component of United States sheep production as some flocks select for increasing litter size to boost productivity. However, there is a conception among shepherds that artificially reared ewe lambs will ultimately result in poor mothers since they were not naturally raised. The objective of this study was to determine if differences in maternal behavior could be detected between ewes raised artificially and those raised naturally and if dam rearing type had an impact on lamb growth performance. Forty-eight ewes were enrolled comprised of 4 equal sized groups: artificially reared primiparous, naturally reared primiparous, artificially reared multi-parous, and naturally reared multi-parous. Ewes were observed using remote cameras to record maternal behaviors toward the lambs during and shortly after parturition. Behavior of 29 ewes during the first hour after parturition was analyzed. Independent multivariable regression models were evaluated for: proportion of time spent grooming, proportion of time spent helping the lambs nurse, number of helpful bouts, and the number of negative bouts. No statistically significant difference (P < 0.05) was detected between artificially reared and naturally reared ewes for the proportion of time spent grooming and the proportion of time spent helping the lambs nurse. Historical flock data were utilized to evaluate lamb growth between artificially and naturally reared ewes. No detrimental associations between artificially reared ewes and lamb weaning weights were observed. This study shows that artificially reared ewes are no different in terms of mothering behaviors and may be used as potential replacement candidates.Item Green Infrastructure Microbial Community Response to Simulated Pulse Precipitation Events in the Semi-Arid Western United States(MDPI AG, 2024-07) Hastings, Yvette D.; Smith, Rose M.; Mann, Kyra A.; Brewer, Simon; Goel, Ramesh; Jack Hinners, Sarah; Follstad Shah, JenniferProcesses driving nutrient retention in stormwater green infrastructure (SGI) are not well quantified in water-limited biomes. We examined the role of plant diversity and physiochemistry as drivers of microbial community physiology and soil N dynamics post precipitation pulses in a semi-arid region experiencing drought. We conducted our study in bioswales receiving experimental water additions and a montane meadow intercepting natural rainfall. Pulses of water generally elevated soil moisture and pH, stimulated ecoenzyme activity (EEA), and increased the concentration of organic matter, proteins, and N pools in both bioswale and meadow soils. Microbial community growth was static, and N assimilation into biomass was limited across pulse events. Unvegetated plots had greater soil moisture than vegetated plots at the bioswale site, yet we detected no clear effect of plant diversity on microbial C:N ratios, EEAs, organic matter content, and N pools. Differences in soil N concentrations in bioswales and the meadow were most directly correlated to changes in organic matter content mediated by ecoenzyme expression and the balance of C, N, and P resources available to microbial communities. Our results add to growing evidence that SGI ecological function is largely comparable to neighboring natural vegetated systems, particularly when soil media and water availability are similar.Item Discovery of a split stellar stream in the periphery of the Small Magellanic Cloud(Oxford University Press, 2024-07) Nidever, David L.I report the discovery of a stellar stream (Sutlej) using Gaia DR3 (third data release) proper motions and XP metallicities located ∼15◦ north of the Small Magellanic Cloud (SMC). The stream is composed of two parallel linear components (‘branches’) approximately ∼8◦ × 0.6◦ in size and separated by 2.5◦. The stars have a mean proper motion of (μRA , μDec. ) = (+0.08 mas yr−1 , −1.41 mas yr−1 ), which is quite similar to the proper motion of stars on the western side of the SMC. The colour–magnitude diagram of the stream stars has a clear red giant branch, horizontal branch, and main-sequence turn-off that are well matched by a PARSEC isochrone of 10 Gyr, [Fe/H] = −1.8 at 32 kpc, and a total stellar mass of ∼33 000 M . The stream is spread out over an area of 9.6 deg2 and has a surface brightness of 32.5 mag arcsec−2 . The metallicity of the stream stars from Gaia XP spectra extends over −2.5≤ [M/H] ≤−1.0 with a median of [M/H] = −1.8. The tangential velocity of the stream stars is 214 km s−1 compared to the values of 448 km s−1 for the Large Magellanic Cloud and 428 km s−1 for the SMC. While the radial velocity of the stream is not yet known, a comparison of the space velocities using a range of assumed radial velocities shows that the stream is unlikely to be associated with the Magellanic Clouds. The tangential velocity vector is misaligned with the stream by nearly 90◦, which might indicate an important gravitational influence from the nearby Magellanic Clouds.Item Drastic hourly changes in hand hygiene workload and performance rates: A multicenter time series analysis(Elsevier BV, 2024-09) Moore, Lori D.; Arbogast, James W.; Robbins, Greg; DiGiorgio, Megan; Parker, Albert E.Background. High hand hygiene (HH) workload is a commonly cited barrier to optimal HH performance. The objective of this study was to assess trends of HH workload as defined by HH opportunities (HHO) and performance rates over different timescales using automated HH monitoring system data. Methods. This multiyear retrospective observational study was conducted in 58 inpatient units located in 10 North American hospitals. HHO and HH rates were analyzed by time series mixed effects general additive model. Results. Median HH rates peaked at 50.0 between 6 and 7 AM with a trough of 38.2 at 5 PM. HHO over hours in a day were the highest at 184 per hospital unit per hour at 10 AM with a trough of 49.0 between 2 and 3 AM. Median rates for day and night shifts were 40.8 and 45.5, respectively (P = .078). Weekend day shift had the lowest median rate (39.4) compared with any other 12-hour shift (P < .1018). The median rates and HHO varied little across days in a week and months. Conclusions. HH workload and performance rates were negatively correlated and changed drastically over hours in a day. Hospitals should consider HH workload in the development and timely delivery of improvement interventions.Item The value of long-term ecological research for evolutionary insights(Springer Science and Business Media LLC, 2024-08) Cocciardi, Jennifer M. et al.; Borokini, Israel T.Scientists must have an integrative understanding of ecology and evolution across spatial and temporal scales to predict how species will respond to global change. Although comprehensively investigating these processes in nature is challenging, the infrastructure and data from long-term ecological research networks can support cross-disciplinary investigations. We propose using these networks to advance our understanding of fundamental evolutionary processes and responses to global change. For ecologists, we outline how long-term ecological experiments can be expanded for evolutionary inquiry, and for evolutionary biologists, we illustrate how observed long-term ecological patterns may motivate new evolutionary questions. We advocate for collaborative, multi-site investigations and discuss barriers to conducting evolutionary work at network sites. Ultimately, these networks offer valuable information and opportunities to improve predictions of species’ responses to global change.Item Updating the Upper Cretaceous (Campanian) Two Medicine Formation of Montana: Lithostratigraphic revisions, new CA-ID-TIMS U-Pb ages, and a calibrated framework for dinosaur occurrences(Geological Society of America, 2024-07) Rogers, Raymond R.; Horner, John R.; Ramezani, Jahandar; Roberts, Eric M.; Carricchio, David J.The Campanian Two Medicine Formation of northwestern Montana, USA, is richly fossiliferous, and discoveries made within the unit over the past century have greatly advanced our appreciation of dinosaur paleobiology and evolution. Previously undifferentiated from a lithostratigraphic perspective, the formation is now subdivided into four new members that include (from base to top) (1) the Rock City Member, (2) the Shields Crossing Member, (3) the Hagans Crossing Member, and (4) the Flag Butte Member. These new formal units and their associated fossil occurrences are also now included in an age model founded on eight high-resolution chemical abrasion−isotope dilution−thermal ionization mass spectrometry (CA-ID-TIMS) U-Pb ages. New age data confirm that the Two Medicine Formation accumulated during much of the Campanian, with deposition spanning ca. 82.4 Ma to 74.4 Ma. New age data further indicate that a major reorganization of depositional systems, marked by a shift from predominantly lacustrine to alluvial facies and accompanied by a dramatic increase in accommodation, transpired near the base of the new Flag Butte Member at ca. 76.3 Ma. This change in depositional regime correlates in age with the Judith River−Belly River discontinuity, which marks the contact between the McClelland Ferry and Coal Ridge Members in the Judith River Formation and coincides with the onset of the Bearpaw transgression in north-central Montana. The new lithostratigraphic and chronostratigraphic framework for the Two Medicine Formation serves to contextualize and calibrate the formation’s rich dinosaur fossil record, which can now be interrogated with increased clarity and precision. These results also provide ground truth for numerical models that explore the structure of the fossil record in relation to alluvial architecture and terrestrial sequence stratigraphy.