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The thermostatic mechanisms of Earth’s persistent habitability remain unresolved. High-resolution Cenozoic C isotope records, P accumulation, and coarse-fraction I/Ca allow recalculation and assessment of controls on the global proportion of total carbon buried as organic carbon (f_org), a regulator of atmospheric CO₂and O₂.f_orgwas suppressed during the Eocene hothouse, coincident with an oxygenated water column and low water-column phosphate. With decreased sea level, the area for efficient organic carbon and phosphate sedimentary burial diminished, leading increasingly to greater water-column phosphate, higher primary productivity, and emergent water column deoxygenation. The sea-level influence on the areal extent of high sedimentation in shelf regions acts as a control on phosphate availability for new production, respiratory demand, and ocean oxygenation, as proposed by hypsographic models [C. J. Bjerrum, J. Bendtsen, J. J. F. Legarth,Geochem. Geophys. Geosys.7, 1–24 (2006)]. During intermediate sea-level highs of the Neogene, pulses of enhanced organic carbon burial prevailed for multimillion years, in response to the redox recycling of phosphate when oxygen minimum zones with O₂< 90 µmol/kg were present. We propose the existence of a self-limiting intermediate sea-level sweet spot with peak C_orgburial due to redox recycling of phosphate, whereby oxygen minimum zones (OMZ) with O₂< 90 µmol/kg impinge on the most C_orgrich continental shelf sediments. Such a sweet spot has narrowed over Earth history due to deepening OMZs, stabilizing both atmospheric O₂and CO₂. Continental marine inundation controls on phosphate availability, and the sedimentary carbon flux, provide a positive-feedback and rectifier to perturbations during inception of the icehouse world. 

We observe and model spin currents arising from chirality and effective spin-exchange interactions in a weakly interacting 6Li Fermi gas. Chirality is introduced by a static displacement between the center of the trapped atoms and the center of an applied magnetic bowl, which produces left- or right-handed spatially varying spin rotation. Spin current is directly observed via oscillations in the centers of mass of the spin-up and spin-down components, which appear to bounce off of or pass through one another, depending on the degree of handedness and s-wave scattering length. We show that this behavior obeys a driven oscillator equation with an effective spin-dependent driving force. Our measurements demonstrate chirality-induced spin selectivity via the direction of the current flow, extending CISS phenomena to Fermi gases. 

Buildings are not only physical infrastructures but also socially and institutionally produced environments that structure access to space, resources and community life. This study draws from human–environment geography, common property theory and scholarship on built environments to conceptualize buildings as shared indoor environments that function as common pool resources and can be governed as common property regimes. Using an ethnographic approach, we examine a large, mixed-use academic–residential building at a U.S. research university to better understand how it was produced and governed as a shared resource. Data from stakeholder interviews, institutional documents and participant observation reveal governance dynamics that align closely with Ostrom’s design principles, including clear boundaries, collective choice, monitoring and sanctions. We identify both the institutional mechanisms and spatial strategies that contribute to sustainable, cooperative use of shared indoor resources. We also propose a conceptual framework that links building governance to broader national design trends, institutional mental models, and localized scarcities and abundances. Our findings offer practical insights for designers, campus planners and institutional decision-makers seeking to foster more inclusive, adaptive and sustainable building use. 

Abstract Many thermobarometric methods applied to granitic composition rocks that crystallized at < 5 kbar yield temperature estimates ~ 50 to 100 °C lower than the widely used haplogranite water-saturated solidus. To address thermobarometric discrepancies, we investigated a shallow-level granitic pluton that is not enriched in fluxing elements such as Li, B, P, or F. The Rito del Medio pluton (RDMP) near Questa, New Mexico contains numerous minerals and inclusions suitable for thermobarometric estimates, and it has abundant miarolitic cavities that represent the final crystallization stages. Occurrences of coexisting melt and fluid inclusions show that groundmass minerals crystallized from a water-saturated magma. After groundmass crystallization, the pluton transitioned to a fluid-dominated system manifested by the crystallization of freestanding minerals contained in the miarolitic cavities. The granite contains mica, feldspar, quartz, primary fluid inclusions in quartz, and accessory minerals including garnet with quartz inclusions. We used minerals and their inclusions in both paragenetic contexts to track changes in P, T, and mineral and fluid compositions that accompanied the magmatic-to-hydrothermal transition. Resultant univariant curves from thermobarometry for the groundmass minerals converge at ~ 1.9 to 2.1 kbar and ~ 590 to 625 °C indicating final magmatic crystallization. To address discrepancies between thermobarometric results and the haplogranite solidus, we performed crystallization experiments at 2 kbar, which show that RDMP compositions magmas complete crystallization at temperatures ~ 620–625 °C. Univariant curves for thermobarometric approaches applied to the RDMP miarolitic cavity minerals converge at ~ 1.5 to 2.1 kbar and ~ 500 to 525 °C defining the transition to hydrothermal crystallization conditions. 

Abstract BE Lyncis (BE Lyn) is a well-studied high-amplitudeδScuti variable star. Recently, Niu et al. analyzed a 39 yr baseline of times of maximum light of BE Lyn, reporting that it is the most eccentric binary known (e ≈ 0.9989) and hosts the nearest black hole (BH) known to date. We analyze Hipparcos and Gaia astrometry of BE Lyn, predicting what the observed proper motion anomaly (PMA) over the 25 yr baseline between the two missions would be were the companion really a ≳17.5M_⊙BH. We find that the predicted PMA is at least an order of magnitude larger than the observed value of ≈1.7 ± 0.8 mas yr⁻¹, regardless of the assumed orientation of the orbit. We predict the expected Gaia DR3RUWEfor different orientations of the putative BH binary, finding that it ranges from ≈2.5 to 4.0, much larger than the reported value of 1.073. The observed value is instead consistent with a low-mass secondary or a single star. We find that BE Lyncis would have received a 7-parameter acceleration solution if it were a BH binary, in contradiction with its absence from the Gaia DR3 non-single star catalogs. Finally, we show that the reported orbit is impossible because the luminous star would overflow its Roche lobe at periastron, irrespective of inclination. We recommend caution in interpreting light-travel time effect models that require very high eccentricities, face-on inclinations, or large companion masses. The observed pulsation timing variations are most likely simply a result of red noise or pulsation phase evolution.