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Glacial retreat due to global warming is exposing large tracts of barren glacial sediments that are quickly colonized by CO2-fixing microbial communities that can constitute the climax community in many high-Arctic, alpine, and Antarctic environments. Despite the potential importance of these processes, little is known about microbial community successional dynamics and rates of carbon (C) sequestration in environments where higher plants are slow or unable to establish. We analyzed microbial community succession and C and N accumulation in newly exposed sediments along an Antarctic glacial chronosequence where moss and microbial autotrophs are the dominant primary producers. During the first 4 years of succession (0 to 40 m from the glacier) algae were the most relatively abundant eukaryotes, but by the second phase studied (8 to 12 years) moss amplicon sequence variants (ASVs) dominated. The rise in moss coincided with a significant buildup of C and N in the sediments. The final two phases of the successional sequence (16 to 20 and 26 to 30 years) were marked by declines in microbial species richness and moss relative abundance, that coincided with significant decreases in both total C and N. These retrogressive declines coincided with a large increase in abundance of predatory Vampyrellidae suggesting a possible mechanism for retrogression in this and perhaps other terrestrial ecosystems at the edge of the cryosphere. These findings have implications for understanding CO2 sequestration and ecosystem succession in microbial-dominated regions of the cryobiosphere where large tracts of land are currently undergoing deglaciation. 

With the shift to remote learning during the COVID-19 pandemic, educators turned to remote exam proctoring software to support integrity for online tests. However, due to the mechanisms used to surveil test-takers, these systems come with significant privacy and security tradeoffs. At the height of the pandemic, Balash et al. (SOUPS ’21) found that test-takers had privacy concerns with remote proctoring but acquiesced due to a number of factors. We investigate how perceptions have changed four years later. To gain a fuller perspective on how users experience these tools now, we replicate Balash et al.’s study with 127 participants who have experienced exam proctoring. We found a significant shift in favor of proctoring software, with greater acceptance of all monitoring methods compared to 2020. This is likely due to the convenience of remote exams and a growing resignation to privacy trade-offs. We discuss these implications and suggest future directions. 

We combined field observations and microcosm experiments on recently deglaciated proglacial soils from Midtre Lovénbreen, Svalbard. Geochemical analyses suggest stronger limitation by nitrogen (N) and phosphorus (P) than by carbon (C). To distinguish between N and P limitation, we caried out microcosm incubations. In +N+P microcosms there was a bloom of rapidly growing soil algae and predatory bacteria resulting in significant shifts in microbial community structure. Addition of P decreased the C:N ratio, changed the structure of the prokaryotic community, and increased the growth of soil algae, mosses, and N-fixing cyanobacteria. Overall, these results indicate that P availability limits the establishment of early microbial primary producers. Given the rapid deglaciation of High Arctic regions, these findings highlight the central role of P in structuring these emerging ecosystems. 

The files contain MetaData (soil temperatures and light flux data) for the period of August 2023 thrugh August of 2025.  The data are from sites 1 and 2 as described in the following papers:   Schmidt SK, MA Cramm, AJ Solon et al. 2025. Biological soil crust microcolonies reveal how microbial communities assemble following retreat of a High Arctic glacier. FEMS Microbes xtaf007. Cimpoiasu MO, O Kuras, H Harrison, et al. 2025. High-resolution 4D electrical resistivity tomography and below-ground point sensor monitoring of High Arctic deglaciated sediments capture zero-curtain effects, freeze–thaw transitions, and mid-winter thawing. The Cryosphere 19: 401–421 Cimpoiasu MO, O Kuras, H Harrison, et al. 2024. Characterization of a deglaciated sediment chronosequence in the High Arctic using near‐surface geoelectrical monitoring methods. Permafrost and Periglacial Processes 35: 157-171. https://doi.org/10.1002/ppp.2220 

Human-subjects researchers are increasingly expected to de-identify and publish data about research participants. However, de-identification is difficult, lacking objective solutions for how to balance privacy and utility, and requiring significant time and expertise. To understand researchers' approaches, we interviewed 18 practitioners who have de-identified data for publication and 6 curators who review data submissions for repositories and funding organizations. We find that researchers account for the kinds of risks described by k-anonymity, but they address them through manual and social processes and not through systematic assessments of risk across a dataset. This allows for nuance but may leave published data vulnerable to re-identification. We explore why researchers take this approach and highlight three main barriers to more rigorous de-identification: threats seem unrealistic, stronger standards are not incentivized or supported, and tools do not meet researchers' needs. We conclude with takeaways for repositories, funding agencies, and privacy experts. 

Abstract Seasonal and El Niño-Southern Oscillation (ENSO) warming result in similar ocean changes as predicted with climate change. Climate-driven environmental cycles have strong impacts on microbiome diversity, but impacts on microbiome function are poorly understood. Here we quantify changes in microbial genomic diversity and functioning over 11 years covering seasonal and ENSO cycles at a coastal site in the southern California Current. We observe seasonal oscillations between large-genome lineages during cold, nutrient rich conditions in winter and spring versus small-genome lineages, includingProchlorococcusandPelagibacter, in summer and fall. Parallel interannual changes separate communities depending on ENSO condition. Biodiversity shifts translate into clear oscillations in microbiome functional potential. Ocean warming induced an ecosystem with less iron but more macronutrient stress genes, depressed organic carbon degradation potential and biomass, and elevated carbon-to-nutrient biomass ratios. The consistent microbial response observed across time-scales points towards large climate-driven changes in marine ecosystems and biogeochemical cycles. 

Abstract The Nucleocapsid protein (N) of SARS-CoV-2 plays a critical role in the viral lifecycle by regulating RNA replication and by packaging the viral genome. N and RNA phase separate to form condensates that may be important for these functions. Both functions occur at membrane surfaces, but how N toggles between these two membrane-associated functional states is unclear. Here, we reveal that phosphorylation switches how N condensates interact with membranes, in part by modulating condensate material properties. Our studies also show that phosphorylation alters N’s interaction with viral membrane proteins. We gain mechanistic insight through structural analysis and molecular simulations, which suggest phosphorylation induces a conformational change in N that softens condensate material properties. Together, our findings identify membrane association as a key feature of N condensates and provide mechanistic insights into the regulatory role of phosphorylation. Understanding this mechanism suggests potential therapeutic targets for COVID infection. 

ABSTRACT Vision underlies many important behaviors in insects generally and in mosquitos specifically. Mosquito vision plays a role in predator avoidance, mate finding, oviposition, locating vertebrate hosts and vectoring disease. Recent work has shown that when sensitized to CO2, the visual responses of Aedes aegypti are wavelength dependent, but little is known about how other olfactory stimuli can modulate visual responses. The visual cues associated with flowers, vertebrate hosts or oviposition sites differ substantially and it is possible that odors might prime the mosquito visual system to respond to these different resources. To investigate the interplay of olfactory and visual cues, we adapted previously used wind tunnel bioassays to use quasi-monochromatic targets (390–740 nm) created with novel LED synthesizers. We coupled these visual targets with CO2 and the odors representative of vertebrate hosts, floral nectar or oviposition sites and assessed responses via 3D tracking of female mosquitos. When CO2 alone was present, we observed a lower preference for wavelengths in the green portion of the visible spectrum with a gradual increase as wavelengths moved towards the violet and red ends of the spectrum. However, when odors associated with both flowers and oviposition sites were present, we observed significant increases in mosquito preference for green (475–575 nm) stimuli. In contrast, when vertebrate host odor was present, we saw increased preference for stimuli across the entire visible spectrum. These odor shifts in mosquito spectral preferences suggest these preferences are not fixed and shift depending on the behavioral context.