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0 to 13.5‰. Our constructed sulfur isotopic mass balance of OCS revealed that anthropogenic sources, not merely oceanic sources, account for much of the missing source of atmospheric OCS.Living organisms expend metabolic energy to repair and maintain their genomes, while viruses protect their genetic material by completely passive means. We have used cryo-electron microscopy (cryo-EM) to solve the atomic structures of two filamentous double-stranded DNA viruses that infect archaeal hosts living in nearly boiling acid Saccharolobus solfataricus rod-shaped virus 1 (SSRV1), at 2.8-Å resolution, and Sulfolobus islandicus filamentous virus (SIFV), at 4.0-Å resolution. The SIFV nucleocapsid is formed by a heterodimer of two homologous proteins and is membrane enveloped, while SSRV1 has a nucleocapsid formed by a homodimer and is not enveloped. SLF1081851 In both, the capsid proteins wrap around the DNA and maintain it in an A-form. We suggest that the A-form is due to both a nonspecific desolvation of the DNA by the protein, and a specific coordination of the DNA phosphate groups by positively charged residues. We extend these observations by comparisons with four other archaeal filamentous viruses whose structures we have previously determined, and show that all 10 capsid proteins (from four heterodimers and two homodimers) have obvious structural homology while sequence similarity can be nonexistent. This arises from most capsid residues not being under any strong selective pressure. The inability to detect homology at the sequence level arises from the sampling of viruses in this part of the biosphere being extremely sparse. Comparative structural and genomic analyses suggest that nonenveloped archaeal viruses have evolved from enveloped viruses by shedding the membrane, indicating that this trait may be relatively easily lost during virus evolution.In multialternative risky choice, we are often faced with the opportunity to allocate our limited information-gathering capacity between several options before receiving feedback. In such cases, we face a natural trade-off between breadth-spreading our capacity across many options-and depth-gaining more information about a smaller number of options. Despite its broad relevance to daily life, including in many naturalistic foraging situations, the optimal strategy in the breadth-depth trade-off has not been delineated. Here, we formalize the breadth-depth dilemma through a finite-sample capacity model. We find that, if capacity is small (∼10 samples), it is optimal to draw one sample per alternative, favoring breadth. However, for larger capacities, a sharp transition is observed, and it becomes best to deeply sample a very small fraction of alternatives, which roughly decreases with the square root of capacity. Thus, ignoring most options, even when capacity is large enough to shallowly sample all of them, is a signature of optimal behavior. Our results also provide a rich casuistic for metareasoning in multialternative decisions with bounded capacity using close-to-optimal heuristics.Wood formation consumes around 15% of the anthropogenic CO2 emissions per year and plays a critical role in long-term sequestration of carbon on Earth. However, the exogenous factors driving wood formation onset and the underlying cellular mechanisms are still poorly understood and quantified, and this hampers an effective assessment of terrestrial forest productivity and carbon budget under global warming. Here, we used an extensive collection of unique datasets of weekly xylem tissue formation (wood formation) from 21 coniferous species across the Northern Hemisphere (latitudes 23 to 67°N) to present a quantitative demonstration that the onset of wood formation in Northern Hemisphere conifers is primarily driven by photoperiod and mean annual temperature (MAT), and only secondarily by spring forcing, winter chilling, and moisture availability. Photoperiod interacts with MAT and plays the dominant role in regulating the onset of secondary meristem growth, contrary to its as-yet-unquantified role in affecting the springtime phenology of primary meristems. The unique relationships between exogenous factors and wood formation could help to predict how forest ecosystems respond and adapt to climate warming and could provide a better understanding of the feedback occurring between vegetation and climate that is mediated by phenology. Our study quantifies the role of major environmental drivers for incorporation into state-of-the-art Earth system models (ESMs), thereby providing an improved assessment of long-term and high-resolution observations of biogeochemical cycles across terrestrial biomes.Images of micrometer-scale domains in lipid bilayers have provided the gold standard of model-free evidence to understand the domains’ shapes, sizes, and distributions. Corresponding techniques to directly and quantitatively assess smaller (nanoscale and submicron) liquid domains have been limited. Researchers commonly seek to correlate activities of membrane proteins with attributes of the domains in which they reside; doing so hinges on identification and characterization of membrane domains. Although some features of membrane domains can be probed by indirect methods, these methods are often constrained by the limitation that data must be analyzed in the context of models that require multiple assumptions or parameters. Here, we address this challenge by developing and testing two methods of identifying submicron domains in biomimetic membranes. Both methods leverage cryo-electron tomograms of ternary membranes under vitrified, hydrated conditions. The first method is optimized for probe-free applications Domains are directly distinguished from the surrounding membrane by their thickness. This technique quantitatively and accurately measures area fractions of domains, in excellent agreement with known phase diagrams. The second method is optimized for applications in which a single label is deployed for imaging membranes by both high-resolution cryo-electron tomography and diffraction-limited optical microscopy. For this method, we test a panel of probes, find that a trimeric mCherry label performs best, and specify criteria for developing future high-performance, dual-use probes. These developments have led to direct and quantitative imaging of submicron membrane domains in vitrified, hydrated vesicles.